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2. The Physical Mechanism of Frequency-Induced Inflection Point for Oil–Paper Insulation Under High-Frequency Square-Wave Voltage.
- Author
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Liu, Kai, Li, Xiaonan, Yang, Yan, Wu, Zihao, Liu, Tong, Zhu, Minghui, and Wu, Guangning
- Subjects
- *
SQUARE waves , *PARTIAL discharges , *VOLTAGE , *INFLECTION (Grammar) , *DECAY constants , *SURFACE charges , *SILICONE rubber - Abstract
High-frequency (HF) oil-immersed transformers with small size and light weight have been paid wide attention by researchers. Its oil–paper insulation frequently withstands HF over-voltages at frequencies of several kilohertz and above, resulting in the too early failure of oil–paper insulation. In order to investigate the effect of HF on oil–paper insulation, this article investigates the partial discharge (PD) characteristics of oil–paper insulation under HF stress. The experimental results show that a frequency-induced inflection point is existed near 10 kHz and the PD parameters of HF voltages is much higher than that ac voltages. Besides, the theoretical mechanism is expounded to interpret and understand the formation process of frequency-induced inflection points more easily. It can be found that the change in frequency causes the change in the charge decay time constant and the residual charge on the insulating surface, resulting in the formation of the frequency-induced inflection point at HF. These results might contribute to determine the characteristics of PDs between HF voltages and ac voltages. It can provide references for the research and production of HF transformers. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
3. Integrated Control-Fluidic Codesign Methodology for Paper-Based Digital Microfluidic Biochips.
- Author
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Wang, Qin, Schlichtmann, Ulf, Cai, Yici, Ji, Weiqing, Li, Zeyan, Cheong, Haena, Kwon, Oh-Sun, Yao, Hailong, Ho, Tsung-Yi, Shin, Kwanwoo, and Li, Bing
- Subjects
- *
BIOCHIPS , *CONDUCTIVE ink , *CARBON nanotubes , *VOLTAGE control , *INK-jet printers , *FLUIDIC devices - Abstract
Paper-based digital microfluidic biochips (P-DMFBs) have recently emerged as a promising low-cost and fast-responsive platform for biochemical assays. In P-DMFBs, electrodes and control lines are printed on a piece of photograph paper using an inkjet printer and carbon nanotubes (CNTs) conductive ink. Compared with traditional digital microfluidic biochips (DMFBs), P-DMFBs enjoy significant advantages, such as faster in-place fabrication with printer and ink, lower costs, and better disposability. Since electrodes and CNT control lines are printed on the same side of this paper, a critical design challenge for P-DMFB is to prevent control interference between moving droplets and the voltages on CNT control lines. Control interference may result in unexpected droplet movements and thus incorrect assay outputs. To address this design challenge, a control-fluidic codesign methodology is proposed in this paper, along with two demonstrative design flows integrating both fluidic design and control design, i.e., the droplet-oriented codesign flow and the electrode-oriented codesign flow. The droplet-oriented flow is suitable for designing biochips with sparse electrodes and relatively larger number of droplets, whereas the electrode-oriented flow is suitable for biochips with dense electrodes and smaller number of droplets. The computational simulation results of real-life bioassays demonstrate the effectiveness of the proposed codesign flows. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
4. Grammatical interference in written papers translated by Russian and American students
- Author
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Galkina Alexandra and V Radyuk Alexandra
- Subjects
Cultural Studies ,Linguistics and Language ,Grammar ,russian ,Computer science ,media_common.quotation_subject ,interference ,to-infinitive ,translation ,Modal verb ,Linguistics ,Education ,lcsh:Philology. Linguistics ,Interference (communication) ,lcsh:P1-1091 ,ComputingMilieux_COMPUTERSANDEDUCATION ,grammar ,lcsh:L ,english ,modal verbs ,media_common ,lcsh:Education - Abstract
Language interference is one of the most common problems in foreign language teaching. Language learners inevitably apply knowledge of their native language to a second language, which leads to linguistic interference. The more differences there are between the two languages, the more prominent the interference between them will be. This paper examines the key issues faced by Russian students learning English and English-speaking students learning Russian and suggests key areas of teaching needed in both disciplines.
- Published
- 2019
5. Invited paper:Characterization of few mode fibers and devices
- Author
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Neethu Mariam Mathew, Karsten Rottwitt, and Lars Gruner-Nielsen
- Subjects
Physics ,business.industry ,Improved algorithm ,02 engineering and technology ,Polarization (waves) ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,010309 optics ,Interferometry ,Few mode fibers ,020210 optoelectronics & photonics ,Optics ,Control and Systems Engineering ,0103 physical sciences ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,business ,Interference ,Instrumentation ,Optical fiber measurements ,Group delay and phase delay - Abstract
This paper reviews characterization techniques for few mode fibers and components. The focus is on interferometric techniques including spatial and spectral resolved imaging (S2). Simple interferometric measurements are shown to be able to give quite comprehensive information including measurement of relative group delay. A new improved algorithm for analyzing S2 data for the case of only two modes is presented. The effect of polarization and rotation of asymmetric modes is treated as well.
- Published
- 2019
6. Dirty-Paper Coding Based Secure Transmission for Multiuser Downlink in Cellular Communication Systems.
- Author
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Wang, Bo and Mu, Pengcheng
- Subjects
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MULTIUSER channels , *LINEAR network coding , *WIRELESS communications , *BROADCAST channels , *COVARIANCE matrices , *PROBABILITY theory - Abstract
This paper studies the secure transmission in a multiuser broadcast channel where only the statistical channel state information of the eavesdropper is available. We propose to apply secret dirty-paper coding (S-DPC) in this scenario to support the secure transmission of one user and the normal (unclassified) transmission of the other users. By adopting the S-DPC and encoding the secret message in the first place, all the information-bearing signals of the normal transmission are treated as noise by potential eavesdroppers and thus provide secrecy for the secure transmission. In this way, the proposed approach exploits the intrinsic secrecy of multiuser broadcasting and can serve as an energy-efficient alternative to the traditional artificial noise (AN) scheme. To evaluate the secrecy performance of this approach and compare it with the AN scheme, we propose two S-DPC-based secure transmission schemes for maximizing the secrecy rate under constraints on the secrecy outage probability (SOP) and the normal transmission rates. The first scheme directly optimizes the covariance matrices of the transmit signals, and a novel approximation of the intractable SOP constraint is derived to facilitate the optimization. The second scheme combines zero-forcing dirty-paper coding and AN, and the optimization involves only power allocation. We establish efficient numerical algorithms to solve the optimization problems for both schemes. Theoretical and simulation results confirm that, in addition to supporting the normal transmission, the achievable secrecy rates of the proposed schemes can be close to that of the traditional AN scheme, which supports only the secure transmission of one user. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
- Full Text
- View/download PDF
7. Practical Dirty Paper Coding With Sum Codes.
- Author
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Rege, Kiran M., Balachandran, Krishna, Kang, Joseph H., and Kemal Karakayali, M.
- Subjects
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CHANNEL coding , *SIGNAL quantization , *CONSTELLATION diagrams (Signal processing) , *DECODING algorithms , *INTERFERENCE (Telecommunication) - Abstract
In this paper, we present a practical method to construct dirty paper coding (DPC) schemes using sum codes. Unlike the commonly used approach to DPC where the coding scheme involves concatenation of a channel code and a quantization code, the proposed method embodies a unified approach that emulates the binning method used in the proof of the DPC result. Auxiliary bits are used to create the desired number of code vectors in each bin. Sum codes are obtained when information sequences augmented with auxiliary bits are encoded using linear block codes. Sum-code-based DPC schemes can be implemented using any linear block code, and entail a relatively small increase in decoder complexity when compared to standard communication schemes. They can also lead to significant reduction in transmit power in comparison to standard schemes. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
8. Secret Writing on Dirty Paper: A Deterministic View.
- Author
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El-Halabi, Mustafa, Liu, Tie, Georghiades, Costas N., and Shamai, Shlomo
- Subjects
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CRYPTOGRAPHY , *INTERFERENCE channels (Telecommunications) , *CODING theory , *INFORMATION theory , *COMPUTER network security , *MATHEMATICAL models , *VECTOR analysis , *GAUSSIAN processes - Abstract
Recently, there has been a lot of success in using the deterministic approach to provide approximate characterization of Gaussian network capacity. In this paper, we take a deterministic view and revisit the problem of wiretap channel with side information. A precise characterization of the secrecy capacity is obtained for a linear deterministic model, which naturally suggests a coding scheme which we show to achieve the secrecy capacity of the degraded Gaussian model (dubbed as “secret writing on dirty paper”) to within half a bit. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
- View/download PDF
9. Mother Tongue Traces of Turkish University Students on Composition Papers Written in English
- Author
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Gencer Elkilic
- Subjects
avoidance ,inter-lingual errors ,Class (computer programming) ,Computer science ,Turkish ,First language ,media_common.quotation_subject ,English Language ,Turkish language ,mother tongue ,Linguistics ,Agreement ,language.human_language ,Ranking (information retrieval) ,Noun ,Quantifier (linguistics) ,language ,General Materials Science ,Student learning ,Interference ,Composition (language) ,composition errors ,media_common - Abstract
The aim of this study was to determine the interference errors on the composition papers of Turkish university students. While Turkish university students learning English are writing compositions, they sometimes confront difficulties related to proper word choices, grammatical structures and other aspects of the language due to the differences of these two languages. The aim of the study was, therefore, to determine inter-lingual errors on the composition papers written in English. 436 papers written by 26, intermediate level, preparatory class students (3 male, 23 female), and 642 papers written by 42 upper intermediate level students (11 male and 31 female), were examined in this study. According to the result of the study, the highest ranking interference errors of Turkish university EFL students were “word for word translation”, omitting the indefinite article, subject-verb agreement and number, quantifier and noun agreement. The study also revealed that intermediate level students committed more errors than those who were upper-intermediate and that most errors were general errors, not interference errors. And also it was clear from the present study that as the level of the students got higher, the number of the errors and interference errors got lower.
- Published
- 2012
10. Unraveling the Mistakes: An Analysis of Student Errors in Translating Literary Texts.
- Author
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Rexhepi, Sadije, Blakaj-Gashi, Albulena, and Haklaj, Agnesa
- Subjects
LITERARY errors & blunders ,NATIVE language ,GERMAN language ,LANGUAGE & languages ,ORTHOGRAPHY & spelling - Abstract
The aim of this paper is to analyse the translation performance of German students at the University of Prishtina when translating literary texts from German into Albanian. The paper focuses on the question of whether errors occur during the translation process in the areas of grammar, orthography, semantics, and sentence structure, including possible interference errors between the two languages. These errors may arise due to uncertainties, carelessness, or the influence of other languages. The interference of German manifests itself primarily in the lexical level and sentence structure. If the languages have differences in sentence structure, this interference leads to grammatically incorrect sentences. An interference of Albanian is also noticeable, primarily on a pragmatic level, which is mainly determined by the cultural context. Errors are a characteristic feature of foreign language learners. They are a phenomenon that affects not only foreign language learners but also native speakers. This paper analyses and classifies the errors that German students at the University of Prishtina make when translating by applying the theoretical, analytical, and contrastive methods in the translation of literary texts. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
11. Dirty-Paper Coding for the Gaussian Multiaccess Channel With Conferencing.
- Author
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Bross, Shraga I., Lapidoth, Amos, and Wigger, Michèle
- Subjects
- *
GAUSSIAN processes , *TRANSMITTERS (Communication) , *RANDOM noise theory , *CODE division multiple access , *CODING theory , *SIGNAL processing , *BIT error rate - Abstract
We derive the capacity region of the two-user dirty-paper Gaussian multiaccess channel (MAC) with conferencing encoders. In this MAC, prior to each transmission block, the transmitters can hold a conference in which they can communicate with each other over error-free bit pipes of given capacities. The received signal suffers not only from additive Gaussian noise but also from additive interference, which is known noncausally to the transmitters but not to the receiver. The additive interference is modeled as Gaussian or uniform over a sphere. We show that the interference can be perfectly mitigated, i.e., that the capacity region without interference can also be achieved in its presence. This holds irrespective of whether the transmitters learn the interference before or after the conference. It follows as a corollary that also for the MAC with degraded message sets, the interference can be perfectly mitigated if it is known noncausally to the transmitters. To derive our results, we generalize Costa's single-user writing-on-dirty-paper achievability result to channels with dependent interference and not-necessarily Gaussian noise. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
12. Writing on Fading Paper, Dirty Tape With Little Ink: Wideband Limits for Causal Transmitter CSI.
- Author
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Borade, Shashi and Zheng, Lizhong
- Subjects
- *
TRANSMITTERS (Communication) , *BROADBAND communication systems , *INTERFERENCE channels (Telecommunications) , *INDUSTRIAL costs , *BANDWIDTHS - Abstract
A wideband Rayleigh fading channel is considered with causal channel state information (CSI) at the transmitter and no receiver CSI. A simple orthogonal code with energy detection rule at the receiver (similar to pulse position modulation in IEEE Trans. Inf. Theory, vol. 46, no. 4, Apr. 2000 and IEEE Trans. Inf. Theory, vol. 52 no. 5, May 2006) is shown to achieve the capacity of this channel in the wideband limit. This strategy transmits energy only when the channel gain exceeds a threshold, hence only needs causal transmitter CSI. In the wideband limit, this capacity without any receiver CSI is the same as the capacity with full receiver CSI, which is proportional to the logarithm of the bandwidth. Similar threshold-based pulse position modulation is shown to achieve the capacity per unit cost of the dirty-tape channel (dirty paper channel with causal transmitter CSI and no receiver CSI), which equals its capacity per unit cost with full receiver CSI. Then, a general discrete channel with i.i.d. states is considered. Each input has an associated cost and a zero cost input “0” exists. The channel state is assumed to be known at the transmitter in a causal manner. Capacity per unit cost is found for this channel and a simple orthogonal code is shown to achieve this capacity. Later, a novel orthogonal coding scheme is proposed for the case of causal transmitter CSI and a condition for equivalence of capacity per unit cost for causal and noncausal transmitter CSI is derived. [ABSTRACT FROM PUBLISHER]
- Published
- 2012
- Full Text
- View/download PDF
13. <Original Paper>The Effect of Acid Concentration on the Emission Intensity of Transition Metal Lines in ICP-AES
- Author
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KEKESI, Tamas
- Subjects
HCl concentration ,ICP-AES ,relative intensity ,interference ,matrix matching ,acid ,sample introduction - Abstract
In order to obtain reliable results by the technique of Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), it is imperative to avoid or correct for interferences caused by the matrix of the solution samples. Differences in the acid concentration between the samples and the standards can significantly affect the analytical results. This effect has been investigated by analyzing several series of solution samples. The increase in the acid concentration is obviously accompanied by an increase in the viscosity, resulting in an initial decrease of the analytical signal. Further increasing the acid concentration, however, brings about a positive effect, which is largely enhanced by applying higher HCl concentrations in the washing solution and is efficiently reduced by purging the solution feeding line of the system. The positive effect is presumably related to the enhancement of excitation. This interpretation is suggested by the comparison of results obtained by two different instruments and different kinds of acid in the samples. The obtained relative intensity functions are suitable for the mathematical correction of matrix-induced interferences, provided the conditions of washing are standardized.
- Published
- 2001
14. INTERFERENCJE LEKSYKALNE W WYPOWIEDZIACH PISEMNYCH SŁOWIAN ZE WSCHODU (NA PODSTAWIE PISEMNYCH PRAC CERTYFIKATOWYCH Z ROKU 2019, POZIOM B1).
- Author
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Przechodzka, Grażyna and Hudy, Wiktorija
- Subjects
POLISH language ,LANGUAGE & languages ,TASKS ,AUTHORS - Abstract
Copyright of Acta Universitatis Lodziensis: Kształcenie Polonistyczne Cudzoziemców is the property of Wydawnictwo Uniwersytetu Lodzkiego and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2021
- Full Text
- View/download PDF
15. New Polyphase Sequence Families With Low Correlation Derived From the Weil Bound of Exponential Sums.
- Author
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Wang, Zilong, Gong, Guang, and Yu, Nam Yul
- Subjects
- *
FAMILIES , *PAPER arts , *MULTIPHASE flow , *STATISTICAL correlation , *SEQUENCE analysis - Abstract
In this paper, the sequence families of which maximum correlation is determined by the Weil bound of exponential sums are revisited. Using the same approach, two new constructions with large family sizes and low maximum correlation are given. The first construction is an analog of one recent result derived from the interleaved structure of Sidel'nikov sequences. For a prime p and an integer M\vert (p-1), the new M-ary sequence families of period p are obtained from irreducible quadratic polynomials and known power residue-based sequence families. The new sequence families increase family sizes of the known power residue-based sequence families, but keep the maximum correlation unchanged. In the second construction, the sequences derived from the Weil representation are generalized, where each new sequence is the elementwise product of a modulated Sidel'nikov sequence and a modulated trace sequence. For positive integers d
- Published
- 2013
- Full Text
- View/download PDF
16. The Formation of 2D Holograms of a Noise Source and Bearing Estimation by a Vector Scalar Receiver in the High-Frequency Band.
- Author
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Pereselkov, Sergey, Kuz'kin, Venedikt, Ehrhardt, Matthias, Matvienko, Yurii, Tkachenko, Sergey, and Rybyanets, Pavel
- Subjects
SOUND pressure ,NOISE ,WATER depth ,ANGULAR distribution (Nuclear physics) ,HOLOGRAPHY ,EXTREME value theory ,HOLOGRAPHIC interferometry - Abstract
The holographic signal-processing method for a single vector scalar receiver (VSR) in the high-frequency band in shallow water is developed in the paper. The aim of this paper is to present the results of the theoretical analysis, numerical modeling, and experimental verification of holographic signal processing for a noise source by the VSR. The developed method is based on the formation of the 2D interferogram and 2D hologram of a noise source in a shallow-water waveguide. The 2D interferograms and 2D holograms for different channels of the VSR (P sound pressure and V X and V Y vibration velocity components) are considered. It is shown that the 2D interferogram consists of parallel interference fingers in the presence of a moving noise source. As a result, the 2D hologram contains focal points located on a straight line, and the angular distribution of the holograms has the main extreme value. It is shown in the paper that the holographic signal-processing method allows detecting the source, estimating the source bearing, and filtering the useful signal from the noise. The results of the source detection, source bearing estimation, and noise filtering are presented within the framework of experimental data processing and numerical modeling. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
17. Adjacent-Channel Compatibility Analysis of International Mobile Telecommunications Downlink and Digital Terrestrial Television Broadcasting Reception in the 470–694 MHz Frequency Band Using Monte Carlo Simulation.
- Author
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Taha, Hussein, Vári, Péter, and Nagy, Szilvia
- Subjects
TELEVISION broadcasting ,DIGITAL television ,TELECOMMUNICATION ,SPECTRUM allocation ,ANTENNAS (Electronics) - Abstract
This paper delves into the imperative need for coexistence and compatibility in the 470–694 MHz frequency band, as mandated by the World Radiocommunication Conference 2015 (WRC-15) and the WRC-23. It focuses on challenges in the coexistence of Digital Terrestrial Television Broadcasting (DTTB) and International Mobile Telecommunications-2020 (IMT-2020) services in downlink-only mode, particularly in adjacent-channel scenarios. Using Monte Carlo simulations, the study evaluates the probability of interference from IMT base stations with DTTB reception. The analysis thoroughly investigates the impact of the IMT transmitter's Adjacent Channel Leakage Ratio (ACLR) and the DTTB receiver's Adjacent-Channel Selectivity (ACS) on the probability of interference. The results demonstrate a significant degradation in the DTTB reception probability at the edge of coverage based on standard assumptions. To address these challenges, this paper provides recommendations for mitigating interference. These include defining enhanced ACLR regulations for IMT base stations, implementing antenna discriminations, providing specialized filters, and establishing national coordination procedures. The research provides valuable insights for informed decision making in spectrum management within the 470–694 MHz band, aiming to facilitate the coexistence of DTTB and IMT-2020 services, in line with international regulations and best practices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. DMT of Parallel-Path and Layered Networks Under the Half-Duplex Constraint.
- Author
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Sreeram, K., Birenjith, S., and Kumar, P. Vijay
- Subjects
DATA transmission systems ,TELECOMMUNICATION ,MULTIPLEXING ,PAPER arts ,COMPUTER networks - Abstract
In this paper, we study the diversity-multiplexing-gain tradeoff (DMT) of wireless relay networks under the half-duplex constraint. It is often unclear what penalty if any, is imposed by the half-duplex constraint on the DMT of such networks. We study two classes of networks; the first class, called KPP(I) networks, is the class of networks with the relays organized in K parallel paths between the source and the destination. While we assume that there is no direct source-destination path, the K relaying paths can interfere with each other. The second class, termed as layered networks, is comprised of relays organized in layers, where links exist only between adjacent layers. [ABSTRACT FROM PUBLISHER]
- Published
- 2013
- Full Text
- View/download PDF
19. Decentralized SINR Balancing in Cognitive Radio Networks.
- Author
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Dhifallah, Oussama, Dahrouj, Hayssam, Al-Naffouri, Tareq Y., and Alouini, Mohamed-Slim
- Subjects
COGNITIVE radio ,RADIO transmitter-receivers ,WIRELESS communications ,SPECTRUM allocation ,OPTIMALITY theory (Linguistics) - Abstract
This paper considers the downlink of a cognitive radio (CR) network formed by multiple primary and secondary transmitters, where each multiantenna transmitter serves a preknown set of single-antenna users. This paper assumes that the secondary and primary transmitters can simultaneously transmit their data over the same frequency bands to achieve high system spectrum efficiency. This paper considers the downlink balancing problem of maximizing the minimum signal-to-interference-plus-noise ratio (SINR) of the secondary transmitters subject to both the total power constraint of the secondary transmitters and the maximum interference constraint at each primary user due to secondary transmissions. This paper proposes solving the problem using the alternating direction method of multipliers, which leads to a distributed implementation through limited information exchange across the coupled secondary transmitters. This paper additionally proposes a solution that guarantees feasibility at each iteration. Simulation results demonstrate that the proposed solution converges to the centralized solution in a reasonable number of iterations. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
20. Elastic-Plastic Stress Analysis of Shrink-fitted Thick FGM Cylinders Elastic-Plastic Stress Analysis of Shrink-fitted Thick FGM Cylinders.
- Author
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Zrinej, Samiha, Laghzale, Nor-Eddine, and Bouzid, Abdel-Hakim A.
- Subjects
STRAINS & stresses (Mechanics) ,MATERIAL plasticity ,YOUNG'S modulus ,YIELD stress ,ANALYTICAL solutions - Abstract
Copyright of FME Transactions is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
21. Adaptive CAPTCHA: A CRNN-Based Text CAPTCHA Solver with Adaptive Fusion Filter Networks.
- Author
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Wan, Xing, Johari, Juliana, and Ruslan, Fazlina Ahmat
- Subjects
ADAPTIVE filters ,CONVOLUTIONAL neural networks ,TEXT recognition ,WEBSITES - Abstract
Text-based CAPTCHAs remain the most widely adopted security scheme, which is the first barrier to securing websites. Deep learning methods, especially Convolutional Neural Networks (CNNs), are the mainstream approach for text CAPTCHA recognition and are widely used in CAPTCHA vulnerability assessment and data collection. However, verification code recognizers are mostly deployed on the CPU platform as part of a web crawler and security assessment; they are required to have both low complexity and high recognition accuracy. Due to the specifically designed anti-attack mechanisms like noise, interference, geometric deformation, twisting, rotation, and character adhesion in text CAPTCHAs, some characters are difficult to efficiently identify with high accuracy in these complex CAPTCHA images. This paper proposed a recognition model named Adaptive CAPTCHA with a CNN combined with an RNN (CRNN) module and trainable Adaptive Fusion Filtering Networks (AFFN), which effectively handle the interference and learn the correlation between characters in CAPTCHAs to enhance recognition accuracy. Experimental results on two datasets of different complexities show that, compared with the baseline model Deep CAPTCHA, the number of parameters of our proposed model is reduced by about 70%, and the recognition accuracy is improved by more than 10 percentage points in the two datasets. In addition, the proposed model has a faster training convergence speed. Compared with several of the latest models, the model proposed by the study also has better comprehensive performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
22. Analytical and Clinical Interference of Sample Hemolysis in Evaluating Blood Biochemical and Endocrine Parameters in Cows.
- Author
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Kovačević, Dražen, Cincović, Marko, Majkić, Mira, Spasojević, Jovan, Djoković, Radojica, Nikolić, Sandra, Došenović Marinković, Maja, Delić Vujanović, Biljana, Obradović, Nemanja, Anđušić, Ljiljana, Čukić, Aleksandar, Petrović, Miloš, Starič, Jože, and Ježek, Jožica
- Subjects
HEMOLYSIS & hemolysins ,COWS ,MASTITIS ,INFANT formulas ,LINEAR equations ,BLOOD testing ,BLOOD sampling - Abstract
Simple Summary: The metabolic profile implies simultaneous determination of carbohydrate, fat, protein, and mineral metabolism parameters as well as endocrinological parameters in the blood of cows. Blood is exposed to a variety of preanalytical factors during sampling, transport to the laboratory, and laboratory preparation for analysis, which may cause hemolysis of the sample. As hemolysis affects the values of the metabolic profile, the analyzed blood parameters may falsely increase or decrease, and the metabolic status of the cows may be misinterpreted. Preventing hemolysis is important because severe hemolysis requires discarding the sample and resampling, which is very resource-intensive. In this paper, three levels of hemolysis were determined for each blood parameter tested: (a) a hemolysis level that does not affect the values of the parameters and allows the results to be issued without restriction; (b) a hemolysis level that affects the values of the parameters but remains within the acceptable biological variability and permits the results to be issued along with a note in the form of a correction formula; and (c) a hemolysis level at which the obtained values of the parameters or the entire sample must be discarded. The results are presented graphically using interferograms, which can be easily implemented in every laboratory after validation. Hemolysis is a common cause of errors in laboratory tests as it affects blood parameters and leads to a positive or negative bias. This study aims to examine the relationship between the level of hemolysis (expressed as cell-free hemoglobin concentration, g/L) and the variability of metabolic and endocrine parameters and to determine the threshold level of hemolysis that causes an analytically and clinically significant bias for the twenty most frequently examined blood parameters in cows. Paired blood samples of 10 mL each were obtained from 30 cows. One was subjected to mechanical trauma and plasma was extracted directly from the other. Hemolyzed and non-hemolyzed samples from the same animal were mixed to obtain final samples with cell-free hemoglobin concentrations of 0, 1, 2, 4, 6, 8, and 10 g/L. Metabolic and endocrine parameters were measured in the samples and their deviation and the linear equation between the level of hemolysis and the deviation were determined. The following threshold values of hemolysis were determined, which correspond to the acceptable analytical (lower value) and clinical (upper value) levels of parameter variability: BHB 0.96 and 4.81; NEFA 0.39 and 3.31; GLU 0.38 and 3.90; ALB 1.12 and 6.11; TPROT 1.40 and 6.80; UREA 6.62 and 20.1; TBIL 0.75 and 5.65; AST 0.11 and 2.18; GGT 1.71 and 8.90, LDH 0.01 and 0.11, ALP 0.97 and 2.95; TGC 1.56 and 15.5; CHOL 1.29 and 8.56; Ca 5.68 and 25.7; P 0.57 and 8.43; Mg 1.10 and 8.47; INS 1.15 and 3.89; T3 8.19 and 15.6; T4 8.97 and 18.5; and CORT 2.78 and 11.22 g/L cell-free hemoglobin. Three decision levels are available for each metabolic and endocrine parameter: if hemolysis is below the lower (analytical) threshold value, results can be reported without restriction; if hemolysis is between the lower and upper thresholds, the results can be issued with guidance in the form of corrective linear equations; and if hemolysis is above the upper (clinical) threshold, the results and sample must be discarded. This method contributes to an optimal approach to hemolysis interference with metabolic profile parameters in blood samples from cows. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
23. Microenvironmental interference with intra-articular stem cell regeneration influences the onset and progression of arthritis.
- Author
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Zhuce Shao, Benlong Wang, Huanshen Gao, and Shenqi Zhang
- Subjects
STEM cells ,CARTILAGE regeneration ,BONE regeneration ,REGENERATION (Biology) ,JOINTS (Anatomy) ,STEM cell research ,ARTHRITIS - Abstract
Studies have indicated that the preservation of joint health and the facilitation of damage recovery are predominantly contingent upon the joint's microenvironment, including cell-cell interactions, the extracellular matrix's composition, and the existence of local growth factors. Mesenchymal stem cells (MSCs), which possess the capacity to self-renew and specialize in many directions, respond to cues from the microenvironment, and aid in the regeneration of bone and cartilage, are crucial to this process. Changes in the microenvironment (such as an increase in inflammatory mediators or the breakdown of the extracellular matrix) in the pathological context of arthritis might interfere with stem cell activation and reduce their ability to regenerate. This paper investigates the potential role of joint microenvironmental variables in promoting or inhibiting the development of arthritis by influencing stem cells' ability to regenerate. The present status of research on stem cell activity in the joint microenvironment is also outlined, and potential directions for developing new treatments for arthritis that make use of these intervention techniques to boost stem cell regenerative potential through altering the intra-articular environment are also investigated. This review's objectives are to investigate these processes, offer fresh perspectives, and offer a solid scientific foundation for the creation of arthritic treatment plans in the future. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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24. Cognition and action: a latent variable approach to study contributions of executive functions to motor control in older adults
- Author
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Caroline Seer, Justina Sidlauskaite, Florian Lange, Stephan P. Swinnen, and Geraldine Rodríguez-Nieto
- Subjects
AGE-RELATED DIFFERENCES ,Geriatrics & Gerontology ,INHIBITION ,QUESTIONNAIRE ,Motor Activity ,INDIVIDUAL-DIFFERENCES ,ONE BRAIN ,structural equation modeling ,Models, Biological ,Structural equation modeling ,Task (project management) ,Executive Function ,Young Adult ,Cognition ,Outcome Assessment, Health Care ,Task Performance and Analysis ,2 HANDS ,motor control ,Humans ,MODULATION ,Control (linguistics) ,bimanual coordination ,Aged ,INTERFERENCE ,Science & Technology ,Working memory ,MEMORY ,aging ,Neuropsychology ,Age Factors ,Motor control ,Cell Biology ,PERFORMANCE ,Executive functions ,executive functions ,Psychology ,Life Sciences & Biomedicine ,Cognitive psychology ,Research Paper - Abstract
Aging is associated with profound alterations in motor control that may be exacerbated by age-related executive functioning decline. Executive functions span multiple facets including inhibition (suppressing unwanted response tendencies), shifting (switching between cognitive operations), and updating (managing working memory content). However, comprehensive studies regarding the contributions of single facets of executive functioning to movement control in older adults are still lacking. A battery of nine neuropsychological tasks was administered to n = 92 older adults in order to derive latent factors for inhibition, shifting, and updating by structural equation modeling. A bimanual task was used to assess complex motor control. A sample of n = 26 young adults served as a control group to verify age-related performance differences. In older adults, structural equation models revealed that performance on the most challenging condition of the complex motor task was best predicted by the updating factor and by general executive functioning performance. These data suggest a central role for working memory updating in complex motor performance and contribute to our understanding of how individual differences in executive functioning relate to movement control in older adults. ispartof: AGING-US vol:13 issue:12 pages:15942-15963 ispartof: location:United States status: published
- Published
- 2021
25. Improving the Sum Rate and Fairness of MIMO Downlink Communications.
- Subjects
FAIRNESS ,VIDEO coding ,RECEIVING antennas ,COVARIANCE matrices - Abstract
The aspects of sum rate and fairness for dirty paper coding (DPC) based MIMO downlink communications are investigated in this paper. We first apply the $\ell _{1}$ -norm fairness measure to formulate the problem of fairness maximization for a given sum rate as an optimization problem. The problem is unfortunately nonconvex and cannot be efficiently solved. To overcome the difficulty, we invoke the uplink-downlink duality to transform the problem back and forth between uplink and downlink communications. An efficient, iterative waterfilling based algorithm is then proposed to yield achievable rates with the best possible fairness values. Simulation results show that the proposed approach offers an enormous gain in the achievable sum rates for a wide range of fairness values, when compared to the popular successive zero-forcing DPC-based and block diagonalization based coding schemes. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
26. Dynamic Spectrum Access for Internet-of-Things Based on Federated Deep Reinforcement Learning.
- Author
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Li, Feng, Shen, Bowen, Guo, Jiale, Lam, Kwok-Yan, Wei, Guiyi, and Wang, Li
- Subjects
DYNAMIC spectrum access ,SMART cities ,TELECOMMUNICATION ,DEEP learning ,WIRELESS communications - Abstract
The explosive growth of Internet-of-Things (IoT) applications such as smart cities and Industry 4.0 have led to drastic increase in demand for wireless bandwidth, hence motivating the rapid development of new techniques for enhancing spectrum utilization needed by new generation wireless communication technologies. Among others, dynamic spectrum access (DSA) is one of the most widely accepted approaches. In this paper, as an enhancement of existing works, we take into consideration of inter-node collaborations in a dynamic spectrum environment. Typically, in such distributed circumstances, intelligent dynamic spectrum access almost invariably relies on self-learning to achieve dynamic spectrum access improvement. Whereas, this paper proposes a DSA scheme based on deep reinforcement learning to enhance spectrum and access efficiency. Unlike traditional Q-learning-based DSA, we introduce the following to enhance the spectrum efficiency in dynamic IoT spectrum environments. First, deep double Q-learning is adopted to perform local self-spectrum-learning for IoT terminals in order to achieve better dynamic access accuracy. Second, to accelerate learning convergence, federated learning (FL) in edge nodes is used to improve the self-learning. Third, multiple secondary users, who do not interfere with each other and have similar operation condition, are clustered for federated learning to enhance the efficiency of deep reinforcement learning. Comparing with the traditional distributed DSA with deep learning, the proposed scheme has faster access convergence speed due to the characteristic of global optimization for federated learning. Based on this, a framework of federated deep reinforcement learning (FDRL) for DSA is proposed. Furthermore, this scheme preserves privacy of IoT users in that FDRL only requires model parameters to be uploaded to edge servers. Simulations are performed to show the effectiveness of theproposed FDRL-based DSA framework. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
27. Improving Interference Analysis for Real-Time DAG Tasks Under Partitioned Scheduling.
- Author
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Wu, Yulong, Zhang, Weizhe, Guan, Nan, and Tang, Yue
- Abstract
Real-time systems with strict timing constraints have been widely applied in many fields. The Directed acyclic graph (DAG) task model has been widely studied and applied to model real-time systems with partial parallelism and precedence constraints in each task. Our paper focuses on the worst-case response time (WCRT) analysis of DAG tasks under partitioned scheduling on multiprocessors. We investigate a parallel structure named $Str$ S t r , which helps obtain more accurate analysis results, and propose a new offline scheduling analysis algorithm named reducing repetitive calculation (RRC). Experiments with synthetic workload are conducted to compare the results calculated by RRC and the state-of-the-art, as well as the observed average response time on a real embedded system. Results show that RRC has better performance in terms of analysis accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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28. Wireless Access in Ultra-Reliable Low-Latency Communication (URLLC).
- Author
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Popovski, Petar, Stefanovic, Cedomir, Nielsen, Jimmy J., de Carvalho, Elisabeth, Angjelichinoski, Marko, Trillingsgaard, Kasper F., and Bana, Alexandru-Sabin
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EXPERIMENTAL design ,WIRELESS communications ,RELIABILITY in engineering - Abstract
The future connectivity landscape, and notably, the 5G wireless systems will feature Ultra-Reliable Low Latency Communication (URLLC). The coupling of high reliability and low latency requirements in URLLC use cases makes the wireless access design very challenging, in terms of both the protocol design and of the associated transmission techniques. This paper aims to provide a broad perspective on the fundamental tradeoffs in URLLC, as well as the principles used in building access protocols. Two specific technologies are considered in the context of URLLC: massive MIMO and multi-connectivity, also termed interface diversity. This paper also touches on the importance of the proper statistical methodology for designing and assessing extremely high-reliability levels. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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29. Interference Mitigation via Relaying.
- Author
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Ayoughi, S. Arvin and Wei Yu
- Subjects
ANTENNAS (Electronics) ,INTERFERENCE (Telecommunication) ,SIGNAL processing ,MIMO systems ,DATA transmission systems - Abstract
This paper studies the effectiveness of relaying for interference mitigation in an interference-limited communication scenario. We are motivated by the observation that in a cellular network, a relay node placed at the cell edge observes a combination of intended signal and inter-cell interference that is correlated with the received signal at a nearby destination, so a relaying link can effectively allow the antennas at the relay and at the destination to be pooled together for both signal enhancement and interference mitigation. We model this scenario by a multiple-input multiple-output (MIMO) Gaussian relay channel with a digital relay-to-destination link of finite capacity, and with correlated noise across the relay and destination antennas. Assuming a compress-and-forward strategy with Gaussian input distribution and quantization noise, we propose a coordinate ascent algorithm for obtaining a stationary point of the non-convex joint optimization of the transmit and quantization covariance matrices. For fixed input distribution, the globally optimum quantization noise covariance matrix can be found in closed-form using a transformation for the relay’s observation that simultaneously diagonalizes two conditional covariance matrices by congruence. For fixed quantization, the globally optimum transmit covariance matrix can be found via convex optimization. This paper further shows that such an optimized achievable rate is within a constant additive gap of the MIMO relay channel capacity. The optimal structure of the quantization noise covariance enables a characterization of the slope of the achievable rate as a function of the relaying link capacity. Moreover, this paper shows that the improvement in spatial degrees of freedom by MIMO relaying in the presence of noise correlation is related to the aforementioned slope via a connection to the deterministic relay channel. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
30. Stochastic Modeling and Analysis of User-Centric Network MIMO Systems.
- Author
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Zhu, Caiyi and Yu, Wei
- Subjects
BEAMFORMING ,WIRELESS cooperative communication ,ANTENNAS (Electronics) ,MIMO systems ,SIGNAL processing ,WIRELESS communications - Abstract
This paper provides an analytical performance characterization of both the uplink (UL) and downlink (DL) user-centric network multiple-input multiple-output (MIMO) systems, where a cooperating base station (BS) cluster is formed for each user individually and the clusters for different users may overlap. In this model, cooperating BSs (each equipped with multiple antennas) jointly perform zero-forcing beamforming to the set of single-antenna users associated with them. As compared with a baseline network MIMO system with disjoint BS clusters, the effect of user-centric clustering is that it improves signal strength in both the UL and DL, while reducing cluster-edge interference in the DL. This paper quantifies these effects by assuming that BSs and users form Poisson point processes and by further approximating both the signal and interference powers using Gamma distributions of appropriate parameters. We show that BS cooperation provides significant gain as compared to single-cell processing for both the UL and DL, but the advantage of user-centric clustering over the baseline disjoint clustering system is significant for the DL cluster-edge users only. Although the analytic results are derived with the assumption of perfect channel state information and infinite backhaul between the cooperating BSs, they nevertheless provide architectural insight into the design of the future cooperative cellular networks. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
31. The Vulnerability of Inland Waterway AIS to GNSS Radio Frequency Interference †.
- Author
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Steiner, Jakub, Havlíček, Jakub, Duša, Tomáš, and Heinrichs, Günter
- Subjects
GLOBAL Positioning System ,RADAR interference ,INLAND navigation ,PHISHING ,AUTOMATIC identification - Abstract
GNSS is an indispensable source of positioning, navigation and timing for many sectors, including inland waterway transport. Unfortunately, GNSS is also vulnerable to interference, including intentional jamming and spoofing. This paper evaluates the vulnerability of one of the key inland waterway systems—the automatic identification system (AIS)—to GNSS jamming and spoofing. The vulnerability is explored via a series of tests conducted in both laboratory and live-sky environments. The results clearly show the negative impact of both types of interference on AIS. The impact included denial of service and reporting of false position. Additionally, the effects on subsequent systems like river information services or nearby vessels are also showcased. The results presented provide valuable insight into the vulnerability of inland waterway transport. The need for understanding the system limitations and vulnerability rises with the increase in the implementation of autonomous systems into the inland waterway sector, as well as other critical infrastructure sectors. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. Design and Analysis of Energy-efficient Algorithm for Wireless Networks.
- Author
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Krishan, R.
- Subjects
WIRELESS LANs ,COMPUTER network traffic ,ALGORITHMS ,ENERGY consumption ,DATA packeting ,FREQUENCY spectra - Abstract
The Industrial, Scientific, and Medical (ISM) frequency spectrum is used by the Wireless Local Area Network (WLAN) for its operation. Due to a limited number of available channels for WLAN operation, frequency channel assignment becomes very difficult. In WLAN, the access points (APs) are widely deployed, and because they share the same frequency, they start interfering with each other and causing more energy consumption. So WLAN frequency channels should be managed and assigned carefully to increase the energy efficiency of the wireless network. This paper proposes an energy-efficient channel assignment algorithm (EECAA) to improve the performance of the network. The suggested approach improves the network's energy efficiency in terms of global delay, packet data loss, and the count of data retransmissions. The extensive simulation study demonstrates that, when compared to the channel handoff scheme and D2MD channel allocation algorithm for various traffic and network conditions, the proposed EECAA method greatly increases network throughput. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Performance Analysis of Low Power Interference Cancellation Architecture for OFDM System.
- Author
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Devarajan, N. Manikanda, Thenmozhi, S., Jayaram, K., and Saravanakumar, R.
- Subjects
LOGIC circuits ,ORTHOGONAL frequency division multiplexing ,TELECOMMUNICATION ,WIRELESS communications ,DATA transmission systems ,COMMUNICATION of technical information - Abstract
Orthogonal Frequency Division Multiplexing (OFDM) is a wireless communication technology that is used for highly reliable and high data rate communication. In a multi-user OFDM system, the interference has occurred in the receiver side between the consecutive OFDM symbols. This interference reduces the performance of the OFDM system. To achieve good quality in received symbols the interference level should be minimized. The conventional cancellation system requires higher interference reduction time and power. These limitations of the conventional interference cancellation architectures for OFDM systems are overcome by proposing efficient and low power interference cancellation architecture. Hence, this paper proposes a novel and efficient architecture based on logic gates for interference cancellation in multi-user OFDM systems. The proposed design consist of multiplexers, inverters and OR gate. The heuristic parameters for the proposed cancellation architecture are computed by performing an XOR operation. Compared to existing architecture, the proposed interference cancellation architecture consumes 7 mW of power consumption in the Virtex processor, 33.59 mW of power consumption in Spartan 3E processor and 0.029 mW of power consumption in the CPLD processor. This proposed interference cancellation architecture consumes fewer hardware resources and consumes low power. The proposed system is designed using Verilog High Definition Language (HDL) and synthesized in Xilinx Project Navigator 12.1i. Further, this paper also proposes gate diffusion input (GDI) based implementation of proposed interference cancellation architecture to analyse a delay and power consumption compared to other logic style implementation. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
34. A Systematic Review of Complementary and Alternative Veterinary Medicine in Sport and Companion Animals: Electrotherapy.
- Author
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Hyytiäinen, Heli K., Boström, Anna, Asplund, Kjell, and Bergh, Anna
- Subjects
ELECTROTHERAPEUTICS ,TRANSCUTANEOUS electrical nerve stimulation ,SPORTS medicine ,ELECTRIC stimulation ,PETS ,CATS ,DOGS ,BRAIN stimulation - Abstract
Simple Summary: Numerous electrotherapeutic methods are commonly used in complementary and alternative veterinary medicine, as well as in conventional veterinary medicine. In these methods, electrical currents are commonly used to affect nerves, muscles, bones, or other tissues. In a systematic literature review, we collected information from published articles on electrotherapies used in horses, dogs, and cats. After screening 5385 articles of potential interest, we identified 41 articles that contributed to answering the overriding question: What is the scientific evidence for electrotherapy in horses, dogs, and cats? For most of the therapies, the number of studies was low with small numbers of animals. Many of the studies were of insufficient scientific quality and the electrotherapy was applied in many different clinical conditions and therapeutic settings. This made it difficult to reach robust conclusions, except for one: no current electrotherapies have sufficiently strong scientific evidence to support clinical effects in the treatment of horses, dogs, or cats with conditions affecting muscles, joints, nerves, or bones. Based on limited promising results, we have listed some electrotherapies that could be evaluated in more detail in high-quality studies. Electrotherapy modalities are currently used in the treatment of animals, but the evidence base supporting their use has not yet been systematically reviewed. Cochrane guidelines, as adapted by the Swedish Agency for Health Technology Assessment and Assessment of Social Services, were followed for this systematic review. A literature search regarding all currently known electrotherapy modalities applied to horses, dogs, and cats was conducted for the years 1980–2020 using three databases: CABI, PubMed, and Web of Science Core Collection. Of the 5385 references found, 41 articles were included in the review: 13 papers on pulsed electromagnetic field therapy (PEMFT), 7 on neural electrical muscle stimulation (NEMS), 5 on transcutaneous electrical nerve stimulation (TENS), 4 on static magnets, 3 on interference, 2 each on percutaneous electrical neural stimulation (PENS), bioelectricity, and diathermy, and 1 each on micro-pulsed stimulation, capacitive coupled electrical stimulation, and microwave therapy. The literature per modality was limited in quantity (mean 3.7 papers). Half of the articles were assessed to have a high risk of bias (20 high, 7 moderate, and 14 low). The existing literature used a spectrum of indications and treatment parameters, which makes comparisons and drawing conclusions to support the use of these modalities in clinical practice challenging. The current scientific evidence is not sufficient to support the clinical effects of electrotherapies for any clinical indication in horses, dogs or cats. The selected suggestive results warrant further high-quality research on PEMFT, NEMS, TENS, and PENS. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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- View/download PDF
35. The effect of Acot2 overexpression or downregulation on the preadipocyte differentiation in Chinese Red Steppe cattle
- Author
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Lixiang Liu, Jian Wu, Yi Gao, Yang Lv, Jiajia Xue, Lihong Qin, Cheng Xiao, Zhongchang Hu, Lichun Zhang, Xiaotong Luo, Yanli Wang, Yang Cao, and Guoliang Zhang
- Subjects
Histology ,Physiology ,interference ,Gene Expression ,Biology ,Diseases of the endocrine glands. Clinical endocrinology ,chemistry.chemical_compound ,Acyl-CoA ,Downregulation and upregulation ,Adipocyte ,Lipid droplet ,Adipocytes ,QP1-981 ,Animals ,RNA, Small Interfering ,Gene ,Transcription factor ,adipocyte differentiation ,Cells, Cultured ,Adipogenesis ,QH573-671 ,Cell Differentiation ,Cell Biology ,RC648-665 ,Lipid Metabolism ,Cell biology ,Acot2 ,chemistry ,ACOT2 ,Cattle ,RNA Interference ,Intramuscular fat ,Thiolester Hydrolases ,Cytology ,Research Article ,Research Paper ,overexpression - Abstract
The quality and nutritional value of beef is closely linked to its content of intramuscular fat (IMF). The differentiation of preadipocytes and the deposition of lipid droplets in the adipocytes are the key to regulate the IMF content. The differentiation of adipocytes is regulated by a series of transcription factors and genes. Acyl-CoA thioesterase 2 (Acot2) hydrolyzes the acyl-coenzyme A (CoA) into free fatty acids and CoA and has the potential to maintain the free fatty acids and acyl CoA at the cellular level. In this work, we detected the expression of the Acot2 gene during the adipocyte differentiation in Chinese Red Steppe cattle, and then interfered and overexpressed the Acot2 gene in the preadipocytes to explore its regulatory role in the adipocyte differentiation. The results showed that the expression and regulation of Acot2 mainly occurred at the later stage of the adipocyte differentiation. The interference with the Acot2 gene significantly inhibited the lipid droplets accumulation and triglyceride content, while its overexpression significantly promoted both of them. The results of this study show that the Acot2 gene is a positive regulator of the adipocyte differentiation and may become a new target to improve the beef quality.
- Published
- 2020
36. Distributed Hybrid Scheduling in Multi-Cloud Networks Using Conflict Graphs.
- Author
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Douik, Ahmed, Dahrouj, Hayssam, Al-Naffouri, Tareq Y., and Alouini, Mohamed-Slim
- Subjects
MOBILE radio stations ,5G networks ,RADIO access networks ,LINEAR programming ,ORTHOGONAL frequency division multiplexing - Abstract
Recent studies on cloud-radio access networks assume either signal-level or scheduling-level coordination. This paper considers a hybrid coordinated scheme as a means to benefit from both policies. Consider the downlink of a multi-cloud radio access network, where each cloud is connected to several base-stations (BSs) via high capacity links and, therefore, allows for joint signal processing within the cloud transmission. Across the multiple clouds, however, only scheduling-level coordination is permitted, as low levels of backhaul communication are feasible. The frame structure of every BS is composed of various time/frequency blocks, called power-zones (PZs), which are maintained at a fixed power level. This paper addresses the problem of maximizing a network-wide utility by associating users to clouds and scheduling them to the PZs, under the practical constraints that each user is scheduled to a single cloud at most, but possibly to many BSs within the cloud, and can be served by one or more distinct PZs within the BSs’ frame. This paper solves the problem using graph theory techniques by constructing the conflict graph. The considered scheduling problem is, then, shown to be equivalent to a maximum-weight independent set problem in the constructed graph, which can be solved using efficient techniques. This paper then proposes solving the problem using both optimal and heuristic algorithms that can be implemented in a distributed fashion across the network. The proposed distributed algorithms rely on the well-chosen structure of the constructed conflict graph utilized to solve the maximum-weight independent set problem. Simulation results suggest that the proposed optimal and heuristic hybrid scheduling strategies provide appreciable gain as compared with the scheduling-level coordinated networks, with a negligible degradation to signal-level coordination. [ABSTRACT FROM PUBLISHER]
- Published
- 2018
- Full Text
- View/download PDF
37. Scalable Deep Reinforcement Learning for Routing and Spectrum Access in Physical Layer.
- Author
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Cui, Wei and Yu, Wei
- Subjects
AD hoc computer networks ,REINFORCEMENT learning ,DEEP learning ,MONTE Carlo method ,SPECTRUM allocation - Abstract
This paper proposes a novel scalable reinforcement learning approach for simultaneous routing and spectrum access in wireless ad-hoc networks. In most previous works on reinforcement learning for network optimization, the network topology is assumed to be fixed, and a different agent is trained for each transmission node—this limits scalability and generalizability. Further, routing and spectrum access are typically treated as separate tasks. Moreover, the optimization objective is usually a cumulative metric along the route, e.g., number of hops or delay. In this paper, we account for the physical-layer signal-to-interference-plus-noise ratio (SINR) in a wireless network and further show that bottleneck objective such as the minimum SINR along the route can also be optimized effectively using reinforcement learning. Specifically, we propose a scalable approach in which a single agent is associated with each flow and makes routing and spectrum access decisions as it moves along the frontier nodes. The agent is trained according to the physical-layer characteristics of the environment using a novel rewarding scheme based on the Monte Carlo estimation of the future bottleneck SINR. It learns to avoid interference by intelligently making joint routing and spectrum allocation decisions based on the geographical location information of the neighbouring nodes. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
38. Underwater Multi-Channel MAC with Cognitive Acoustics for Distributed Underwater Acoustic Networks.
- Author
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Yun, Changho
- Subjects
UNDERWATER acoustics ,MULTICHANNEL communication ,ACCESS control ,AUTONOMOUS underwater vehicles ,COGNITIVE radio - Abstract
The advancement of underwater cognitive acoustic network (UCAN) technology aims to improve spectral efficiency and ensure coexistence with the underwater ecosystem. As the demand for short-term underwater applications operated under distributed topologies, like autonomous underwater vehicle cluster operations, continues to grow, this paper presents Underwater Multi-channel Medium Access Control with Cognitive Acoustics (UMMAC-CA) as a suitable channel access protocol for distributed UCANs. UMMAC-CA operates on a per-frame basis, similar to the Multi-channel Medium Access Control with Cognitive Radios (MMAC-CR) designed for distributed cognitive radio networks, but with notable differences. It employs a pre-determined data transmission matrix to allow all nodes to access the channel without contention, thus reducing the channel access overhead. In addition, to mitigate the communication failures caused by randomly occurring interferers, UMMAC-CA allocates at least 50% of frame time for interferer sensing. This is possible because of the fixed data transmission scheduling, which allows other nodes to sense for interferers simultaneously while a specific node is transmitting data. Simulation results demonstrate that UMMAC-CA outperforms MMAC-CR across various metrics, including those of the sensing time rate, controlling time rate, and throughput. In addition, except for in the case where the data transmission time coefficient equals 1, the message overhead performance of UMMAC-CA is also superior to that of MMAC-CR. These results underscore the suitability of UMMAC-CA for use in challenging underwater applications requiring multi-channel cognitive communication within a distributed network architecture. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. MIMO-UFMC Transceiver Schemes for Millimeter-Wave Wireless Communications.
- Author
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Buzzi, Stefano, D Andrea, Carmen, Li, Dejian, and Feng, Shulan
- Subjects
MIMO systems ,WIRELESS communications ,ORTHOGONAL frequency division multiplexing ,MATHEMATICAL models ,PHASE noise - Abstract
The universal filtered multicarrier (UFMC) modulation is among the most considered solutions for the realization of beyond orthogonal frequency division multiplexing (OFDM) air interfaces for future wireless networks. This paper focuses on the design and analysis of a UFMC transceiver equipped with multiple antennas and operating at millimeter-wave carrier frequencies. This paper provides the full mathematical model of an MIMO-UFMC transceiver, taking into account the presence of hybrid analog/digital beamformers at both ends of the communication links. Then, several detection structures are proposed, both for the case of single-packet isolated transmission and for the case of multiple-packet continuous transmission. In the latter situation, this paper also considers the case in which no guard time among adjacent packets is inserted, trading off an increased level of interference with higher values of spectral efficiency. At the analysis stage, several considered detection structures and transmission schemes are compared in terms of bit-error rate, root-mean-square error, and system throughput. The numerical results show that the proposed transceiver algorithms are effective and that the linear minimum mean-square error (MMSE) data detector is capable of well managing the increased interference brought by the removal of guard times among consecutive packets, thus yielding throughput gains of about 10%–13%. The effect of phase noise at the receiver is also numerically assessed, and it is shown that the recursive implementation of the linear MMSE exhibits some degree of robustness against this disturbance. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
40. Gaussian Broadcast Channels With Intermittent Connectivity and Hybrid State Information at the Transmitter.
- Author
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Lin, Shih-Chun and Wang, I.-Hsiang
- Subjects
- *
GAUSSIAN channels , *TRANSMITTERS (Communication) , *WIRELESS communications , *SIGNAL-to-noise ratio , *LINEAR network coding - Abstract
In wireless networks, the link connectivity may be intermittent due to shadowing, burstiness of data arrival, or uncoordinated resource allocation. In this paper, we model the intermittence of links as Bernoulli distributed random channel states, termed intermittence channel states, and study the impact of the corresponding channel state information at the transmitter (CSIT) in a two-user Gaussian broadcast channel (BC). Moreover, due to the heterogeneous timeliness of intermittence channel states, the CSIT considered in this paper is hybrid. More specifically, the CSIT of each link can be perfectly (causally or non-causally) available, delayed, or not available. When the links are connected, we adopt a general setting that the received signal-to-noise ratios can be different. Our contribution is the characterization of the capacity regions of intermittent Gaussian BC to within bounded gaps for all combinations of hybrid CSIT, except for scenario DN (delayed CSIT of receiver 1, no CSIT of receiver 2). For scenario DN, we propose an opportunistic physical layer network coding scheme that achieves a strictly larger degree-of-freedom (DoF) region than the no-CSIT DoF region. As a corollary, single-user CSIT is able to increase the sum DoF for intermittent Gaussian BC (also the capacity region for the erasure BC, as a by-product). This result is in sharp contrast to the recent negative result by Davoodi and Jafar, where it is shown that for fast-fading multiple-input single-output BC with continuous channel states, single-user CSIT does not help at all in terms of sum DoF. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
41. Tobacco industry interference: A review of three South East Asian countries
- Author
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Bungon Ritthiphakdee, May Myat Cho, Widyastuti Soerojo, Worrawan Jirathanapiwat, and Mary Assunta
- Subjects
0301 basic medicine ,Adult ,Economic growth ,Adolescent ,WHO Framework Convention on Tobacco Control ,030106 microbiology ,interference ,India ,Article 5.3 ,Tobacco industry ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Surveys and Questionnaires ,Humans ,030212 general & internal medicine ,Lagging ,South east asian ,Asia, Southeastern ,Framework Convention on Tobacco Control ,Aged ,Government ,lcsh:Public aspects of medicine ,Tobacco control ,lcsh:RA1-1270 ,General Medicine ,Middle Aged ,Pulp and paper industry ,Dissent and Disputes ,tobacco industry ,Transparency (graphic) ,Corporate social responsibility ,Business - Abstract
Background: The WHO Framework Convention on Tobacco Control (FCTC) Article 5.3 requires governments to protect tobacco control policies from the commercial interest of the tobacco industry (TI). TI interference is the biggest barrier to implementing comprehensive tobacco control measures. Objective: This paper reviews the extent of the TI's interference in tobacco control policy development in three countries, Thailand, Myanmar, and Indonesia, and the governments' efforts to protect these policies. Methods: The paper draws on incidents of TI interference reported in the 2016 Tobacco Industry Interference Index: ASEAN Report on Implementation of the WHO FCTC Article 5.3. Base data were obtained through a questionnaire on twenty most commonly reported incidents of interference from the FCTC Article 5.3 Guidelines recommendations. A scoring system was developed. Results: All three countries faced varying levels of TI interference. Thailand, though known for its stringent tobacco control measures, still faced interference while Myanmar remains vulnerable. Indonesia faced the highest industry interference which may explain why it is lagging behind in tobacco control and remains a nonparty to the WHO FCTC. The TI gains access to government officials through offers of technical assistance and its corporate social responsibility activities. Transparency in dealing with the TI is needed in all three countries. Most governments have not set up disclosure procedures when dealing with the TI. Conclusion: Outside the Department/Ministry of Health, other departments remain unaware of Article 5.3, not utilizing its strength to regulate the TI. More concerted effort is needed to implement Article 5.3 to achieve greater success in tobacco control.
- Published
- 2017
42. An Experimental Implementation of China Digital Radio (CDR) Broadcasting in Hubei.
- Author
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Gao, Li, Liu, Jun, Huang, Yihang, and Men, Aidong
- Subjects
DIGITAL audio broadcasting ,INTELLIGENT networks ,REGRESSION discontinuity design ,BROADCASTING industry ,QUALITY of service ,ELECTRONIC services - Abstract
This paper presents the research and implementation of a China Digital Radio (CDR) experimental network in Hubei, China with two FM-CDR transmitting stations and four FM-band channels. To study the coverage discontinuity problem in a large service area, the experimental network employs an intelligent networking solution that incorporates multiple service channels carrying Broadcast and Data Services (BADS) and a Common-Regional-Information Channel (CRIC) carrying both service data and system information. The electronic service guide (ESG) carried by CRIC can inform the receivers about the available contents from current and adjacent stations, which can significantly improve the service quality in the overlapping areas, especially under mobile reception environment. Two RF tuners are used in the receiving terminals to access the CRIC, and the BADS channel, respectively. This paper first presents the frequency analysis and coverage tests of the experimental network, and then summarizes the coverage performances with different transmission parameter combinations. The goal is to gain experience in frequency planning, coverage prediction, as well as supportable services of CDR digital audio broadcasting. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
43. State-Dependent Gaussian Interference Channels: Can State Be Fully Canceled?
- Author
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Duan, Ruchen, Liang, Yingbin, and Shamai Shitz, Shlomo
- Subjects
GAUSSIAN channels ,INTERFERENCE (Telecommunication) ,TRANSMITTERS (Communication) ,CODING theory ,ALGORITHMS - Abstract
The state-dependent Gaussian interference channel (IC) and Z-IC are investigated, in which two receivers are corrupted by the same but differently scaled states. The state sequence is noncausally known at both transmitters, but not known at either receiver. Three interference regimes are studied, i.e., the very strong, strong, and weak regimes. In the very strong regime, the capacity region is characterized under certain channel parameters by designing a cooperative dirty paper coding between the two transmitters to fully cancel the state. In the strong regime, points on the capacity region boundary are characterized under certain channel parameters by designing an achievable scheme based on rate splitting, layered dirty paper coding, and successive state cancellation. In the weak regime, the sum capacity is obtained by independent dirty paper coding at two transmitters. For all the above regimes, the capacity achieves that of the IC/Z-IC without state. Comparison between the state-dependent regular IC and the Z-IC suggests that even with one interference-free link, the Z-IC does not necessarily perform better, because dirty paper coded interference in the regular IC facilitates to cancel the state through the cooperative dirty paper coding between the transmitters. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
44. On the Outage Capacity of Opportunistic Beamforming With Random User Locations.
- Author
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Samarasinghe, Tharaka, Inaltekin, Hazer, and Evans, Jamie S.
- Subjects
BEAMFORMING ,POISSON processes ,RADIO transmitter fading ,TELECOMMUNICATION systems ,WIRELESS communications - Abstract
This paper studies the outage capacity of a network consisting of a multitude of heterogeneous mobile users and operating according to the classical opportunistic beamforming framework. The base station is located at the center of the cell, which is modeled as a disk of finite radius. The random user locations are modeled using a homogeneous spatial Poisson point process. The received signals are impaired by both fading and location dependent path loss. For this system, we first derive an expression for the beam outage probability. This expression holds for all path loss models that satisfy some mild conditions. Then, we focus on two specific path loss models (i.e., an unbounded model and a more realistic bounded one) to illustrate the applications of our results. In the large system limit, where the cell radius tends to infinity, the beam outage capacity and its scaling behavior are derived for the selected specific path loss models. This paper also studies opportunistic schemes that achieve fairness among the heterogeneous users. Numerical evaluations are performed to give further insights and to illustrate the applicability of the outage capacity results even to a cell having a small finite radius. [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
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45. Spectrum Sharing of HAPS and Fixed Link in Millimeter Waves.
- Author
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Shamsan, Zaid Ahmed
- Subjects
MILLIMETER waves ,TECHNOLOGICAL innovations ,SHARING ,ALTITUDES - Abstract
A High Altitude Platform System (HAPS) is an emerging technology that can potentially bring connectivity to areas that are not partially or totally covered by cellular networks. However, allocating certain frequency bands for the HAPS alongside wireless Fixed Service (FS) imposes some restrictions on operating the HAPS systems to ensure no interference occurs between the two systems (HAPS and FS). This paper presents an analytical study of the spectrum sharing between the HAPS and the FS in millimeter waves, namely in 38- and 47-GHz bands. Some potential and significant interference scenarios have been applied in order to investigate the spectrum-sharing situations in urban and suburban areas. The Carrier to Interference plus Noise Ratio (CINR) has been adopted as the main criterion to assess the performance of the HAPS. It is found that the HAPS and FS systems can simultaneously share the 38- and 47-GHz bands with some restrictions to HAPS altitude, allowable CINR, and location of the HAPS user. These restrictions differ depending on the area coverage type. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. Impact of Action-Dependent State and Channel Feedback on Gaussian Wiretap Channels.
- Author
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Dai, Bin, Li, Chong, Liang, Yingbin, Ma, Zheng, and Shamai Shitz, Shlomo
- Subjects
GAUSSIAN channels ,SECRECY ,TRANSMITTERS (Communication) - Abstract
We investigate the state-dependent Gaussian wiretap channel with noncausal channel state information at the transmitter (GWTC-N-CSIT), and explore whether three strategies (i.e., taking action on the state, legitimate receiver’s channel output feedback, and combining the former two strategies together) help to enhance the secrecy capacity of the GWTC-N-CSIT. To be specific, we first determine the secrecy capacity of the GWTC-N-CSIT with noiseless feedback. Next, we derive lower and upper bounds on the secrecy capacity of the GWTC-N-CSIT with action-dependent state. Finally, we derive lower and upper bounds on the secrecy capacity of the GWTC-N-CSIT with both action-dependent state and noiseless feedback, and show that these bounds meet for a special case. Numerical results of this paper indicate that all three strategies enhance the secrecy capacity of the GWTC-N-CSIT. The study of this paper offers new options for enhancing the secrecy rates of the state-dependent wiretap channel models. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
47. Sum Rate and Fairness Analysis for the MU-MIMO Downlink Under PSK Signalling: Interference Suppression vs Exploitation.
- Author
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Salem, Abdelhamid, Masouros, Christos, and Wong, Kai-Kit
- Subjects
INTERFERENCE suppression ,FAIRNESS ,MULTIPLE access protocols (Computer network protocols) ,PHASE shift keying ,SHELLFISH fisheries ,MONTE Carlo method - Abstract
In this paper, we analyze the sum rate performance of multi-user multiple-input-multiple-output (MU-MIMO) systems, with a finite constellation phase-shift keying (PSK) input alphabet. We analytically calculate and compare the achievable sum rate in three downlink transmission scenarios: 1) without precoding; 2) with zero forcing (ZF) precoding; and 3) with closed form constructive interference (CI) precoding technique. In light of this, new analytical expressions for the average sum rate are derived in the three cases, and Monte Carlo simulations are provided throughout to validate the analysis. Furthermore, based on the derived expressions, a power allocation scheme that can ensure fairness among the users is also proposed. The results in this work demonstrate that the CI strictly outperforms the other two schemes, and the performance gap between the considered schemes increases with the increase in MIMO size. In addition, the CI provides higher fairness and the power allocation algorithm proposed in this paper can achieve maximum fairness index. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
48. New Extension Constructions of Optimal Frequency-Hopping Sequence Sets.
- Author
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Niu, Xianhua and Xing, Chaoping
- Subjects
SPREAD spectrum communications ,CONSTRUCTION ,CHAOTIC communication - Abstract
In this paper, a general framework of constructing the optimal frequency-hopping sequence (FHS) sets is presented based on the designated direct product. Under this framework, we obtain infinitely many new optimal FHS sets by combining some one-coincide (OC) sequence sets that are newly constructed in this paper with some known optimal FHS sets. Our constructions are also based on extension method. However, our constructions give new and flexible parameters due to the free choice of OC sequence set. As a result, our constructions allow a great flexibility of choosing parameters of FHS sets for a given frequency-hopping spread spectrum system. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
49. Energy Efficiency Optimization With Interference Alignment in Multi-Cell MIMO Interfering Broadcast Channels
- Author
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Jie Tang, Arman Shojaeifard, Emad Alsusa, Daniel K. C. So, and Khairi Ashour Hamdi
- Subjects
Green radio (GR) ,multiple-input multiple-output (MIMO) ,multicell MIMO interfering broadcast channel ,energy efficiency (EE) ,energy efficiency optimization ,subgradient method ,Receivers ,telecommunication power management ,Mathematics ,energy conservation ,search problems ,Signal to noise ratio ,interference suppression ,singular value decomposition ,bisection searching scheme ,MIMO ,intracell interference cancellation ,Array signal processing ,multiple input multiple output IFBC system ,Dirty paper coding ,signal-to-noise ratio ,intercell interference cancellation ,Algorithm ,gradient methods ,Efficient energy use ,Optimization ,cellular radio ,Maximum power principle ,channel coding ,SNR ,interference nulling ,Data_CODINGANDINFORMATIONTHEORY ,wireless channels ,Transmitting antennas ,multiple input multiple output (MIMO) ,dirty paper coding ,Singular value decomposition ,Electronic engineering ,MIMO communication ,Wireless ,Electrical and Electronic Engineering ,multiple access channel and broadcast channel duality principle ,Subgradient method ,hybrid DPC-IA approach ,Computer Science::Information Theory ,business.industry ,interference alignment ,radiofrequency interference ,Maximization ,water filling power adaptation scheme ,gradient-based power adaptation scheme ,Interference ,business - Abstract
Characterizing the fundamental energy efficiency (EE) performance of multiple-input-multiple-output interfering broadcast channels (MIMO-IFBC) is important for the design of green wireless system. In this paper, we propose a new network architecture proposition based on EE maximization for Multi-Cell MIMO-IFBC within the context of interference alignment (IA). Particularly, EE is maximized subject to maximum power and minimum throughput constraints. We propose two schemes to optimize EE for different signal-to-noise ratio (SNR) regions. For high-SNR operating regions, we employ a grouping-based IA scheme to jointly cancel intra- and inter-cell interferences and thus transform the MIMO-IFBC to a single-cell MIMO scenario. A gradient-based power adaptation scheme is proposed based on water-filling power adaptation and singular value decomposition to maximize EE for each cell. For moderate SNR cases, we propose an approach using dirty paper coding (DPC) with the principle of multiple access channel and broadcast channel duality to perform IA while maximizing EE in each cell. The algorithm in its dual form is solved using a subgradient method and a bisection searching scheme. Simulation results demonstrate the superior performance of the proposed schemes over several existing approaches. It also shows that interference-nulling-based IA approaches outperform hybrid DPC-IA approach in high-SNR region, and the opposite occurs in low-SNR region.
- Published
- 2015
50. Effects of Armature Characteristics on Armature-Rail Contact Performance.
- Author
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Cheng, W., Yuan, W., Zhao, Y., and Yan, P.
- Subjects
ARMATURES ,ELECTROMAGNETIC launchers ,ANSYS (Computer system) ,ELECTROMAGNETIC rail guns ,ELECTROMAGNETIC forces - Abstract
Armature-rail contact performance determines contact resistance between the armature and rail in electromagnetic launch, and the contact resistance directly affects the efficiency of the launch system. Besides, poor contact performance between the armature and rail will results in erosion, gouging, and other issues in launch. These issues will induce surface damage for the rail, and affect the repetitive launch. So it’s important to improve the armature-rail contact performance. As the characteristics of the rail are relatively stationary in the system, more research was done on the effect of armature characteristics (such as material, shape of the contact, thickness of the neck, and structure of the empennage). In this paper, method of combining ANSYS and pressure test paper was used to study the armature-rail contact performance. The dynamic changing process of the armature-rail contact state was observed by ANSYS, and the final contact state in the case of prepressed experiment was observed by pressure test paper and pressure analysis system. Results from ANSYS and pressure test paper would be comparative analyzed in order to get a more accurate conclusion in the condition of actual experiments. The conclusion of this paper is instructive on optimizing armature design and improving armature-rail contact performance. [ABSTRACT FROM PUBLISHER]
- Published
- 2017
- Full Text
- View/download PDF
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