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This paper presents an elliptical-shaped multi-orbital truncated patch antenna applicable forsub-6 GHz bands. The sub-6 GHz bands cover 5.8 GHz high-speed wireless communication. The antenna is designed on a Poly Dimethylsiloxane (PDMS) substrate. PDMS is used for designing the proposed antenna. It is a flexible substrate with a dielectric constant εr value of 2.7 and a loss tangent tan δ value of 0.022. The substrate dimension is 20x15x1.6 mm3in which a patch is created with the size of 12.5x13 mm2. The proposed antenna resonates at 6.2 GHz showing a reflection coefficient (s11) value of -37 dB. The impedance bandwidth of the antenna is 1.225 GHz in the range of 5.5-6.725 GHz frequency, and the maximum peak gain is about 3.5 dB. The proposed antenna is simulated, fabricated, and experimentally tested. [ABSTRACT FROM AUTHOR]

With the rapid progress in the field of wireless communication, the demand for antenna with miniature size and light weight becomes a necessary requirement in today's world. Most suitable antenna in this category is "Microstrip Patch Antenna (MPA)". In this paper parametric analysis of MPA design structure as per footprint equations, Substrate material, Feeding Techniques and Design parameters are analyzed keeping in view of various Vedic shapes. SSMPA has been recently developed by the researchers which has exhibited improved radiation properties with improved polarization. The design of the SSMPA has been taken from a holy sign in Hindu mythology and has exhibited enhancement in the bandwidth of an MPA. The slots of the SSMPA help in modifying the surface current distribution of the patch. The shape basically helps the charge particles in accelerating and decelerating, which improves the bandwidth and radiation characteristics. Antenna parameters like "Gain, S11 (Return Loss), Bandwidth, Directivity, VSWR" are to be compared for various designs respect to wireless applications. This paper looks at the Swastika and other Vedic shaped MPA and the various advantages of its usage for wireless applications. [ABSTRACT FROM AUTHOR]

Network traffic and load are only expected to increase. Data is lost while being sent between nodes and devices as a result of traffic congestion at bottlenecks. WLANs are becoming the go-to technology for access in hotspot locations, workplaces, and residences. A station in a wireless local area network may be able to connect to several access points (APs). So, deciding which AP is "optimum" from a selection of potential candidates is a pertinent question. The user merely associates the AP with the strongest received signal strength while using IEEE 802.11. But this could lead to a substantial load imbalance among a number of APs. With only a minor modification to the load distribution mechanism, adopting load balancing can improve efficiency and utilization in addition to reducing processing delays. To increase the effectiveness of the WLAN, we provide a dynamic load balancing strategy in this paper. The network and user overhead will be reduced by the suggested dynamic strategy. The suggested method utilizes network load and throughput as performance criteria for performing load balancing. The method's viability is checked using Riverbed Modeller Simulator. The experimental findings validate the effectiveness of the proposed technique in enhancing network throughput and reducing access point congestion. [ABSTRACT FROM AUTHOR]

Reasonable field configuration can improve crop growth environment and increase system yield in intercropping systems. To further improve the field configuration technology for high yield and efficiency in the soybean-maize strip intercropping system in Southwest China, the soybean-maize strip intercropping system was used as the research object, and two factor split zone design was adopted. The effects of two bandwidths of 2.0 m (B1) and 2.4 m (B2) and four plant spacings of 9 cm (P1), 11 cm (P2), 14 cm (P3), and 18 cm (P4) on soybean biomass accumulation, allocation, grain filling, and yield were comprehensively analyzed. The results showed that the net photosynthetic rate of each plant spacing treatment under B2 bandwidth was higher than that of B1, and the two--year average increased by 14.26% compared with B1 under B2. At the same bandwidth, the net photosynthetic rate reached the maximum in B1P4 and B2P4, which increased by 13.57% and 25.21% compared with B1P1 and B2P1 at flowering stage, respectively. The biomass accumulation of soybean population increased and then decreased with the increase of plant spacing under the two bandwidths, and reached the maximum at B1P3 and B2P2, respectively, and B2 increased by 9.82%--22.08% compared with B1 at maturity stage. And the increase of bandwidth and plant spacing promoted the accumulation and transfer of soybean post-flowering matter to grain. Compared with B1, post-flowering dry matter accumulation and dry matter transfer increased by 13.82--28.01% and 13.38%--37.76% under B2 treatment, respectively, and the proportion of grain matter accumulation increased to 41.80%--44.26%. The increase of biomass accumulation improved the grain filling process, and the active grain-filling period (D) of soybean under B2 was extended by 2--3 days compared with B1. The mean grain-filling rate reached its maximum at P4 and increased by 5.80% and 6.58% compared with P1 under the two bandwidths. The yield results showed that, with the increase of bandwidth and plant spacing, the effective plants decreased, and the seeds per plan and 100-seed weight increased in the soybean-maize strip intercropping model. The soybean yield under B2 bandwidth increased by 22.32%--36.87% compared with B1, it reached the maximum in B1P3 and B2P2 under the two bandwidths, respectively, and increased by 17.83%--26.44% and 10.71%--10.76% compared with B1P1 and B2P1 for two years. In summary, the soybean plant spacing of 11 cm at the bandwidth of 2.4 m can effectively improve the post-flowering dry matter accumulation and allocation, promote grain filling, increase the number of seeds per plant and 100-seed weight, improve soybean population yield, and achieve the high yield and high efficiency in the soybean-maize intercropping system. [ABSTRACT FROM AUTHOR]

Antenna design is usually done on FR4 substrates, since they have a dielectric constant of 4.4, and a loss tangent of 0.02. The proposed microstrip patch antenna operates at 28 GHz and incorporates substrate-integrated waveguides (SIW) in a 0.8 mm thick FR4 substrate into the design to increase bandwidth performance so that the 5G network can function reliably. In comparison with conventional patch antennas, substrate-integrated waveguides bear the advantage of being able to shift to a frequency of 29 GHz, therefore resulting in a more effective antenna. A slot of eyebolt shape has been added to the patch to increase antenna gain. The design was simulated with HFSS software, and it was able to attain a maximum bandwidth of 8 GHz (28%), a gain of 5.5 dB, and a minimal return loss of −38 dB. The VSWR of this antenna is 1.02, which indicates good impedance matching, and a high efficiency of 87% has been achieved as a result. This is a low-profile antenna that combines enhanced bandwidth with the ability to be mounted at the edge of a device, making it an ideal choice for the use of 5G technology to enable machine-to-machine communication. [ABSTRACT FROM AUTHOR]

Electrocardiogram (ECG)-gated single photon emission computed tomography myocardial perfusion imaging (GSPECT-MPI) is widely used for assessing coronary artery disease. Phase analysis on GSPECT-MPI can assess left ventricular mechanical dyssynchrony quantitatively on standard GSPECT-MPI alongside myocardial perfusion and function assessment. It has been shown that phase variables by GSPECT-MPI correlate well with tissue Doppler imaging by echocardiography. Main phase variables quantified by GSPECT-MPI are entropy, bandwidth, and phase standard deviation. Although those variables are automatically obtained from several software packages including Quantitative Gated SPECT and Emory Cardiac Toolbox, the methods for their measurement vary in each package. Several studies have shown that phase analysis has predictive value for response to cardiac resynchronization therapy and prognostic value for future adverse cardiac events beyond standard GSPECT-MPI variables. In this review, we summarize the basics of phase analysis on GSPECT-MPI and usefulness of phase analysis in clinical practice. [Display omitted] • Phase variables can be obtained fully automatically from ECG gated SPECT-MPI. • Phase analysis has predictive and prognostic value in various clinical situations. • Phase variables should be routinely reported for SPECT-MPI studies. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agronomica Sinica is the property of Crop Science Society of China 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.)

In general, an antenna is an interface that transmits signal data and receives incoming signal data. The radio waves received through this interface help to do the necessary things for the transmitter and receiver circuit systems used there. Also a radio transmitter antenna transmits different waves generated from the current generated at its tip to different areas. In this paper, the functions of increasing its bandwidth by making changes in some dimensions of the antenna are proposed. The oscillating current used in its transmitter area increases its vibration waves. This increases the amount of airwaves generated there and the number of data transmitted through it. So its bandwidth is more likely to be high. Furthermore these functions generate varying magnetic fields so that the time taken by the cross-sectional magnetic fields of the antenna varies. [ABSTRACT FROM AUTHOR]

An integer linear programming (ILP) model was developed with the intention of reducing the quantity of network spectrum resources while maintaining spectrum contiguity and spectrum continuity restrictions. The techniques that were just outlined have the goal of decreasing the amount of bandwidth that is used by a network; however, they do not consider the issue of spectrum fragmentation. As a result of this, many authors have zeroed in on the issue of spectrum fragmentation and presented a wide range of potential remedies. By separating a single request into many more manageable sub-requests, the Ensemble algorithm makes it less likely that a connection would be denied. However, to process the request, this will necessitate an increase in the number of guard bands and transponders that are used. This will come at a cost. EONs proposed a novel approach to the spectrum's compactness that they developed (SCS). Even though deciding on a compactness threshold can significantly cut down on the amount of spectral fragmentation that takes place, doing so is notoriously difficult for a number of different reasons. [ABSTRACT FROM AUTHOR]

In General, the 5G is a fifth-generation technology that works at speeds of 4G to 100 times the network speed. The main objective of introducing modern information technologies is to facilitate and facilitate access to public services. The use of new technologies is a key factor in improving the overall structure of public administration and increasing its efficiency. In addition, it is important to improve the infrastructure of all types of communications. The telecom operators are often willing to invest more in infrastructure development. In this paper, a new model was proposed to enhance the bandwidth allocation and utilization. It is a requirements-based network that allows the users to increase the speed of wireless networks. This proposed method also increases the amount of data that can be transmitted over wireless networks. [ABSTRACT FROM AUTHOR]

Most of the internet users connect through wireless networks. Major part of internet traffic is carried by Transmission Control Protocol (TCP). It has some design constraints while operated across wireless networks. TCP is the traditional predominant protocol designed for wired networks. To control congestion in the network, TCP used acknowledgment to delivery of packets by the end host. In wired network, packet loss signals congestion in the network. But rather in wireless networks, loss is mainly because of the wireless characteristics such as fading, signal strength etc. When a packet travels across wired and wireless networks, TCP congestion control theory faces problem during handshake between them. This paper focuses on finding this misinterpretation of the losses using cross layer approach. This paper focuses on increasing bandwidth usage by improving TCP throughput in wireless environments using cross layer approach and hence named the proposed system as CRLTCP. TCP misinterprets wireless loss as congestion loss and unnecessarily reduces congestion window size. Using the signal strength and frame error rate, the type of loss is identified and accordingly the response of TCP is modified. The results show that there is a significant improvement in the throughput of proposed TCP upon which bandwidth usage is increased. [ABSTRACT FROM AUTHOR]

The research work presents, constrained network coding technique to ensure the successful data transmission based composite channel cmos technology using dielectric properties. The charge fragmentation and charge splitting are two components of the filtered switch domino (FSD) technique. Further behavior of selected switching is achieved using generator called conditional pulse generator which is employed in Multi Dynamic Node Domino (MDND) technique. Both FSD and MDND technique need wide area compared to existing single nodekeeper domino technique. The aim of this research is to minimize dissipation of power and to achieve less consumption of power. The proposed research, works by introducing the method namely Interference and throughput aware Optimized Multicast Routing Protocol (IT-OMRP). The main goal of this proposed research method is to introduce the system which can forward the data packets towards the destination securely and successfully. To achieve the bandwidth and throughput in optimized data transmission, proposed multicast tree is selected by Particle Swarm Optimization which will select the most optimal host node as the branches of multi cast tree. Here node selection is done by considering the objectives residual energy, residual bandwidth and throughput. After node selection multi cast routing is done with the concern of interference to ensure the reliable and successful data transmission. In case of transmission range size is higher than the coverage sense range, successful routing is ensured by selecting secondary host forwarders as a backup which will act as intermediate relay forwarders. The NS2 simulator is used to evaluate research outcome from which it is proved that the proposed technique tends to have increased packet delivery ratio than the existing work. [ABSTRACT FROM AUTHOR]

This paper proposes a novel wideband, highgain, compact Vivaldi antenna operating in the 14.7-20.5 GHz frequency range, where the antenna is fed by the substrate integrated waveguide (SIW). A Negative Index Metamaterial (NIM) has been designed, with its parameters extracted using MATLAB software. The NIM was developed to address the deficiencies of conventional Antipodal Vivaldi antennas. With a measured gain of over 5.3 dBi, the fabricated antenna performs satisfactorily across the entire bandwidth. Due to its low profile and short transversal dimension, the proposed antenna is suitable for antenna arrays; consequently, the proposed antenna design could be a viable option for modern communication and radar systems. [ABSTRACT FROM AUTHOR]

Until now, the fourth generation (4G) communication system is already been standardized. But, Fifth Generation (5G) is defined as the upcoming major task for mobile communication systems beyond the current deployed 4G. In this research article an inverted U-Shaped slot single-band rectangular microstrip patch antenna for mm- wave 5G (Fifth Generation) applications is proposed. The proposed antenna achieved a high bandwidth by choosing the proper selection of slot dimensions and position in the radiating patch. The overall size of the proposed antenna is 4 x 5 mm² (LxW) with a 0.508 mm substrate height. The proposed inverted U-Shaped slot patch antenna resonates over a frequency range from 63.28-90 GHz having a super-wide impedance bandwidth of 26.76 GHz. A maximum gain of 6.11 with a maximum radiation efficiency of 92.48% at 79 GHz is also observed. The gain of 4.04 dBi, 5.99 dBi and 5.99 dBi at frequencies 71.03, 75, and 80 GHz, respectively are also achieved. Other radiation parameters like E and H-plane, surface current and 3D (Three-Dimensional) gain plots are also studied and analyzed. The proposed antenna has a super-wide bandwidth and suitable for 5G mm-wave (millimeter wave) communication. The proposed design can also be used for satellite and radar communication as 40-75 GHz for V-band, 60-90 GHz for E-band and 75-110 GHz for W-band are the new proposed satellite bands. [ABSTRACT FROM AUTHOR]

A computational grid needs to be cost-effective and highly reliable. It must have the ability to transfer maximum amount of data for end-to-end delivery. Many research works on computational grids conclude with a binary state of operation. Although some research reveals that, the grids operate with multiple states of connections and operations, they are silent about the mentioned constraints. Since there are multi-state operations, the reliability depends on the load, bandwidth and cost. This paper proposes a Genetic Algorithm (GA) based approach for optimization of reliability of computational grid with desired reliability under cost and bandwidth constraints. The method is well explained through illustration and its implementation on some Grid networks. The efficient encoding, cross-over, mutation and selection operation of the proposed scheme ensures the fast convergence to the optimal solution. On comparison, the proposed method is observed to be more efficient than the existing ones. [ABSTRACT FROM AUTHOR]

ICT has greatly changed how research, teaching and learning is done. In the past, these activities were aided mainly by manual databases consisting of paper or print material records. However, over the period of time this has dramatically changed to digital electronic formats such as portable document format (PDF). The goal of this paper was to examine the use of online databases by Nuclear Scientists of Ghana Atomic Energy Commission and review the literature available. A systematic review of 20 articles from 1970 to 2021 was conducted. The review covered studies on both quantitative and qualitative research approaches both locally and abroad. The findings revealed that from the older literature, awareness of the existence of online databases by patrons in their institutions was low. However from the current literature the trend has changed with patrons now been much aware of these online databases. Some problems identified as hindering the access to online databases included low bandwidth speed, and cost of infrastructure which are stumbling blocks especially in developing countries of which Ghana is a part. Recommendations included the provision and expansion of infrastructure, training programmes, information literacy, subscription to current and relevant online databases, conducting regular surveys and funding and financing of electronic resources. It is essential libraries are supported to improve access and usage whiles creating awareness of the numerous benefits that can be gained by research and academic institutions in channelling their energies into having current, available electronic resources for their patrons for teaching, learning and research.. [ABSTRACT FROM AUTHOR]

The optical communication system is preferred over microwave and radio frequency communication systems because of license free operation. Simulative analysis of 10gbps bandwidth using different optical communication channels have been performed in this paper. The different modulation formats of QAM and PSK have been compared for its performances under all the three optical channels OWC, FSO, and LOS-FSO which are an unguided form of optical communication. The optical channels under these modulation formats are extensively used in Digital Video Broadcasting Communication. The parameters such as Q-factor, BER and Eye height can be obtained by varying the wavelengths in the range of 850 nm 1064 nm, 1330 nm and 1550 nm. From the design and performance analysis, the system with the maximum Q-factor and minimum BER can be found for the wavelength of 1064 nm. [ABSTRACT FROM AUTHOR]

In the present scenario, orthogonal frequency division multiplexing (OFDM) waveform technique is playing a significant part in smart hospitals. Still, its impact is not effective in smart hospitals due to the numerous limitations such as loss of bandwidth due to the use of guard band, spectrum leakage, high peak to average power (PAPR), high detection delay, and thus along. Right now, fifth-generation (5G) employment is becoming regularized around the world and the state-of-the-art radio system is expected to meet all the demands of smart hospitals. High spectrum access, massive capacity, high throughput, and low PAPR are the requirements of smart healthcare hospitals. The digital hospital has seen tremendous progression in bandwidth requirements. From transmitting medical images to wearable devices, networks must operate at maximum speeds to safeguard patient care. The selection of competent transmission technologies will play an important role in the regularization of digital hospitals equipped with 5G. In the projected work, we focus on the implementation of novel waveforms such as Non-orthogonal multiple access (NOMA), Universal filter multi-carrier (UFMC), and filter bank multi-carrier (FBMC) system. Several parameters such as power spectrum density, bit error rate, capacity, and PAPR of advanced waveforms and OFDM methods are analyzed and studied. [ABSTRACT FROM AUTHOR]

The thinness of a graph is a width parameter that generalizes some properties of interval graphs, which are exactly the graphs of thinness one. Graphs with thinness at most two include, for example, bipartite convex graphs. Many NP-complete problems can be solved in polynomial time for graphs with bounded thinness, given a suitable representation of the graph. Proper thinness is defined analogously, generalizing proper interval graphs, and a larger family of NP-complete problems are known to be polynomially solvable for graphs with bounded proper thinness. It is known that the thinness of a graph is at most its pathwidth plus one. In this work, we prove that the proper thinness of a graph is at most its bandwidth, for graphs with at least one edge. It is also known that boxicity is a lower bound for the thinness. The main results of this work are characterizations of 2-thin and 2-proper thin graphs as intersection graphs of rectangles in the plane with sides parallel to the Cartesian axes and other specific conditions. We also bound the bend number of graphs with low thinness as vertex intersection graphs of paths on a grid (B k -VPG graphs are the graphs that have a representation in which each path has at most k bends). We show that 2-thin graphs are a subclass of B 1 -VPG graphs (moreover, of L-graphs, that is, B 1 -VPG graphs admitting a representation that uses only one of the four possible shapes ⌊,⌋⌈,⌉), and that 3-thin graphs are a subclass of B 3 -VPG graphs. We also show that B 0 -VPG graphs may have arbitrarily large thinness, and that not every 4-thin graph is a VPG graph. [ABSTRACT FROM AUTHOR]

A bandwidth-parameterized active disturbance rejection synchronization control (ADRSC) is proposed for the parallel electro-coating conveyor. The Laplacian matrix is extracted from the newly defined adjacent-cross-coupling errors and embedded in the controller. It is shown that the proposed ADRSC possesses the capability to achieve synchronization by reformulating cross-coupling as average disturbance to be rejected, thus reducing the dynamics to the canonical form of chained integrators. Furthermore, the upper bound of the bandwidth is established as the trade-off between the accuracy of synchronization and stability. The main contribution of this paper is to extend the active disturbance rejection principle to the accommodation of cross-coupling in synchronization. Simulations and experiments show that this proposed method is effective and practical. • Laplacian matrix from newly defined coupling errors. • Proposal of ADRSC for synchronization in Laplacian-matrix-embedding way. • Trade-off at the upper bound of bandwidth parameter. [ABSTRACT FROM AUTHOR]

We consider the kernel-based classifier proposed by Younso (2017). This nonparametric classifier allows for the classification of missing spatially dependent data. The weak consistency of the classifier has been studied by Younso (2017). The purpose of this paper is to establish strong consistency of this classifier under mild conditions. The classifier is discussed in a multi-class case. The results are illustrated with simulation studies and real applications. [ABSTRACT FROM AUTHOR]

In this paper we designed microstrip patch antenna by using metamaterial to improve antenna bandwidth. We inserted Complementary Split Ring Resonator (CSRR) structure between the ground and patch in the substrate. We compared our design with the conventional microstrip patch antenna in point of bandwidth. We obtained bandwidth improvement by 800MHZ. Simulation was obtained by using High Frequency Structure Simulation (HFSS) simulator. [ABSTRACT FROM AUTHOR]

The coupling mechanism of a loop‐type ground radiation antenna is investigated in this paper. We use the equivalent circuit model of the antenna and a full‐wave simulation to explain the coupling mechanism of the antenna. We analyze the effects of various antenna parameters on the coupling between the antenna element and the ground plane to examine the conditions for enhancing the coupling. Based on simulations with the equivalent circuit model, full‐wave simulations, and measurements, we propose optimal design considerations for the antenna. The findings of this study will aid the design and understanding of loop‐type ground radiation antennas for mobile devices. [ABSTRACT FROM AUTHOR]

In a software defined network, there are various hosts and switches. Often multiple connections exist from one host to another through the switches. These connections require different amount of bandwidth as well as time delay. The proposed work Cost Optimized Flow Control (COFC) aims at finding the most efficient path between a pair of hosts and accordingly deactivates certain switches to let them go to sleep. This requires knowledge about topology of the network which is stored in a software-defined-network (SDN) controller. SDN decouples all the flow control activity from physical forwarding of packets. Flow control is entirely performed by the SDN controller as it determines the switches that can remain in sleep mode unless cost in its alternative paths crosses a threshold. This preserves energy and also optimizes the objectives bandwidth and delay. [ABSTRACT FROM AUTHOR]

So far, management practitioners and scholars alike assume that raises in the contractual absolute maximum bandwidth of Internet connections increase the attitudinal bonds of customers with their access provider. The present study broadens this perspective: In a sample of up to 752 German-speaking Internet users with a wireline Internet access at home, it explores two relative speed characteristics of broadband connections as potential determinants of customer affinity with an access provider. The two reference-dependent aspects comprise customer quality experiences in terms of delivered transmission speeds (1) relative to the maximum down- and upload bandwidths as per customer contract, and (2) relative to speeds emphasized in advertisements of a consumer's access provider. Furthermore, correlations are analyzed between the frequency with which customers use speed tests to check the quality of their wireline Internet connection and their attitudinal bonds with their access provider. Attitudinal bonding is broken down into customer satisfaction with the performance of the current wireline Internet access at home and propensity to churn at the earliest opportunity. Multivariate regression analysis reveals that the impression that advertised wireline access bandwidths are exaggerated compared to the speeds actually delivered and – to a lesser extent – the perception that the contractual maximum speed is reached only in a low share of a customer's Internet sessions significantly decrease customer satisfaction and significantly increase customer inclination to churn. The effects of the two speed assessments are not independent of one another: Perceived speed exaggerations in a provider's ads impair customer bonds less (more) strongly if the experienced share of Internet sessions with speeds below the contractual maximum bandwidth is high (low). More frequent speed testing reduces customer bonding, especially in case that advertised speeds of a customer's provider are experienced as overblown. The results suggest that wireline Internet access providers can increase the attitudinal bonds with their customers by abstaining from emphasizing maximum speeds in their advertising, which customers rarely reach under standard everyday conditions. [ABSTRACT FROM AUTHOR]

The relationship between network structure and access to novel information has fascinated social scientists for decades, culminating in the recent identification of the bandwidth-diversity tradeoff. Yet, existing work focuses on a unidimensional conception of network ties that leaves many important sources of novel information unexplored. We unpack bandwidth, identifying three factors that govern the transmission behavior of network ties: capacity (the ability of a tie to transmit content), frequency (the average time between tie activations), and redundancy (the extent to which a tie reaches persons who are connected to each other). Empirical analyses and simulation models reveal new types of ties, as well as the conventional variety, that open promising research avenues. [ABSTRACT FROM AUTHOR]

Assigning bandwidth to sensors in a Wireless Sensor Network (WSN), while using Time Division Multiple Access (TDMA) protocol, remains an important problem. Even if many solutions were proposed in the literature, nevertheless, and since 2013, we are mainly focused on the critical study and the improvement of Masri's approach published in Telecommunication Systems journal. In this paper, we introduce an extended version of our previous approaches (see Tarek Azizi and Rachid Beghdad, 2013, 2014, 2016) based on three fundamental concepts: network architecture, TDMA protocol, and data aggregation, in order to assign the maximum bandwidth to all sensor nodes. Three solutions will be presented in detail: Spiral-Based Clustered Data Aggregation (SBCDA) architecture, Tree-Based Clustered Data Aggregation (TBCDA), and Tree-Based ClusteredWireless Sensor Network (TBC-WSN). Aggregating data can reduce the number of the packets transmitted to the sink. This is the reason why, in the three approaches here described, each cluster head (CH) collects and aggregates received packets from its child nodes, before transmitting the resulting packet to its parent, until the data reaches the sink node (base station). With a number of simulations, we will demonstrate that our approaches are very competitive with Masri's proposition, and also with two other recent works. [ABSTRACT FROM AUTHOR]

In this paper, a novel conformal-strip excited asymmetric rectangular dielectric resonator antenna with a defected ground is proposed for ultra-wide band application. The material used for investigation is FR-4 having dielectric constant 4.3 and dissipation factor 0.025. The proposed geometry offers 124.32% impedance bandwidth for |S11|<-10 dB, i.e. 2.8-12 GHz exciting higher order modes. The proposed antenna is suitable for many wireless applications like S-band, C-band, X-band, WLAN and WiMAX. Prototype offers 8.3 dBi maximum gain at 10 GHz and 93% efficiency at 3 GHz. The prototype is fabricated and it shows concurrence in simulated and measured results. [ABSTRACT FROM AUTHOR]

Currently the development of digital technology has advanced very rapidly, as well as data storage and data transfer. As the development of information technology and the use of data that increasingly large, it will be a main factor that affects to the company’s business. The amount of data that must be processed both at headquarters and other branch offices make the process of data exchange become the main issue in term of speed and delay. Due to data exchange being a top priority in the company, often the WAN network bandwidth used by the file system, email system, proxy, web system becomes peak or full during peak hours thus slowing down accessing file or email system. One method to reduce bandwidth usage is almost full is to use WAN Optimization tools. WAN Optimization has several functions, including Data Streamlining, Transport Streamlining, and Application Streamlining. The purpose of this study is to analyze performance network when WAN optimization was applied in the system. Data is taken from simulated file transfers conducted several days and at different hours. Data were analyzed using Wireshark tools and calculation formula. The results can be seen if there is a significant increasing performance, delay become better from 287 ms to 0.604 ms for file size 93 MB and jitter increased 12.4% better. It can be concluded that with the optimization of WAN, the process of data transfer becomes more efficient both in bandwidth and time during working hours. [ABSTRACT FROM AUTHOR]

This paper investigates the optimal modified tracking performance of multi-input multi-output (MIMO) networked control systems (NCSs) with packet dropouts and bandwidth constraints. Some explicit expressions are obtained by using co-prime factorization and the spectral decomposition technique. The obtained results show that the optimal modified tracking performance is related to the intrinsic properties of a given plant such as non-minimum phase (NMP) zeros, unstable poles, and their directions. Furthermore, the modified factor, packet dropouts probability and bandwidth also impact the optimal modified tracking performance of the NCSs. The optimal modified tracking performance with channel input power constraint is obtained by searching through all stabilizing two-parameter compensator. Finally, some typical examples are given to illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

Quality of service parameters of cognitive radio, like, bandwidth, throughput and spectral efficiency are opti- mized using adaptive and demand based genetic algorithm. Simulation results show that the proposed method gives better real life solution to the cognitive radio network than other known approach. [ABSTRACT FROM AUTHOR]

Router-assisted concepts have been proposed in many research areas including reliable multicast protocols. These concepts can limit the implosion and repair locality problems in an effective way by attributing the role of repair locality to the specific router close to the point of packet loss. Several router-assisted reliable multicast protocols have been proposed in the literature. However, the extent of the reliability benefit of combining sender-initiated and receiver-initiated protocol classes is not known. This paper quantifies the reliability gain of combining classes for reliable multicasting in lossy networks. We define the delivery delay, the bandwidth consumption, and the buffer requirements as the performance metrics for reliability. We then use simulations to study the impact of multicast group size and loss rate on the performance of combining protocol classes. Our numerical results show that combining classes significantly improves the delivery delay, reduces the consumption of the network bandwidth and minimizes the buffer size at the routers compared to receiver-initiated class alone. The performance gains increase as the size of the network and the loss rate increase, making the combination of classes approach more scalable with respect to these parameters. [ABSTRACT FROM AUTHOR]

Structural modifications on microstrip patch antenna design for performance enhancement offer improvements and advantages only up to a certain limit. However, with the use of novel material in the patch area, the performance of a microstrip patch antenna can further be enhanced in terms of gain and bandwidth. In this paper, a nanomaterial-based slotted rectangular microstrip patch antenna is proposed for gain and bandwidth enhancement in Wireless Local Area Network (WLAN) applications. A conventional copper rectangular microstrip antenna (MSA) with a rectangular slot in the patch area is first fabricated and then nanomaterial is deposited in the slot area. Two types of metallic nanoparticulate thin films are deposited using Gold Nanoparticles (Au NPs) and a combination of alternate Silver-Gold-Silver Nanoparticles (Ag-Au-Ag NPs) in the slot area and the antenna parameters analyzed. A comparison between the conventional slotted MSA, and the fabricated antenna with the two different nanoparticulate thin films is presented. It is found that the Au NPs based antenna shows a 12.5 % improvement in bandwidth for a return loss of −31 dB and a 0.5 dB enhancement in gain with a nanomaterial film thickness of 264 nm. The composite Ag-Au-Ag NPs based antenna shows even better performance than the former one with an 18.75 % improvement in bandwidth for a return loss of −30 dB along with gain enhancement of 2 dB with a nanomaterial film thickness of 330 nm. Both the Au NPs and Ag-Au-Ag NPs based antennas are found to resonate at 5.89 GHz and 5.81 GHz showing an electrical size reduction of 32.09 % and 31.15 %, respectively compared to the conventional rectangular MSA. [ABSTRACT FROM AUTHOR]

Using MANETs for real time applications is always a challenge as the network is extremely dynamic with brisk topology changes. Despite this, several real time schedulers have been developed that aimed at providing QoS to ad hoc nodes. The quality of service (QoS) is standardized in terms of capacity, reliability, link quality, delays/jitters, and network cost. Thus, for QoS, the better transmission should be maintained at end user as well as at the transmitting unit. QoS of a network is affected by delays and bandwidth allocated for transmission. For an efficient network, it is required to predict these metrics during transmission. For this, in this paper, integration of quaternion-based Kalman filter is performed that predicts the required bandwidth and the network delays with higher accuracy. From the analysis, it is shown that bandwidth can be optimized but it is not possible to aloof delays in the network. Thus, while implementing such admission control procedures, estimation process allows control over delays and sustain them from going beyond a certain threshold value. The model proposed is a novel approach and has not been formulated in any of previous work related to QoS in MANETs. The effectiveness of model is demonstrated using both simulation and real time results. [ABSTRACT FROM AUTHOR]

Neurocomputational models eliminates the complex, lengthy and time consuming mathematical procedures for design, analysis and calculating performance parameters of Microstrip antenna. No single ANN based model has been proposed till date for calculating all parameters of circular microstrip antennas simultaneously. This paper presents a Neuro-Computational (NC) approach for estimation of all performance parameters such as Return Loss (RL), Voltage Standing Wave Ratio (VSWR), resonant frequency (f r ), Band-Width (BW), Gain(G), Directivity(D) and antenna efficiency(η) of Circular Microstrip Patch Antenna (CMPA) simultaneously. The difficulty in calculating the parameters of these antennas lies due to the involvement of a large number of physical parameters including their associated optimal values. It is indeed very difficult to formulate an exact numerical solution merely on practical observations based empirical studies. In order to circumvent this problem, an alternative solution is achieved using artificial neural network (ANN). Feed-Forward Back-Propagation Artificial Neural Network (FFBP-ANN) trained with Levenberg-Marquardt algorithm is used for estimation of different performance parameters of CMPA. The results of NC estimation are in very agreement with simulated, measured and theoretical results. [ABSTRACT FROM AUTHOR]

Wireless sensor networks composed of individual nodes that are able to interact with the environment by monitoring or sensing physical parameters. However, these sensors are deployed randomly and in large scale which creates a huge number of redundant sensed data which saturates network resources and consumes nodes energy. Many applications of WSNs require Quality of service (QoS) in terms of high bandwidth for real time applications including multimedia audio and video without much delay. In this scope, and to reduce the number of transmitted packets to sink node, data aggregation may be effective technique, which is a critical function of WSNs. The main goal of data aggregation algorithms is to gather and aggregate data in an energy efficient manner so that network lifetime is enhanced, and bandwidth reserved for each node maximized. Eliminating collisions and idle listening for low energy consumption in the network is a crucial issue which will be done by the use of deterministic access protocols as TDMA which are more power efficient since nodes in the network can enter inactive states until slot times will be assigned to them. Our contribution focus on maximizing bandwidth reserved for each sensor node. In this paper we present a Spiral-Based Clustered with Data Aggregation (SBCDA) architecture approach combining data aggregation with TDMA protocol in WSNs for improving connectivity and avoiding inter-cluster collisions and to increase bandwidth reserved for each sensor node, by computing the length of the superframe generated by all sensor nodes in the network. We conclude with possible future research directions in affecting each time slot to each sensor node. [ABSTRACT FROM AUTHOR]

In this paper, we show that the multiplicative bias correction (MBC) techniques can be applied for generalized Birnbaum–Saunders (GBS) kernel density estimators. First, some properties of the MBC-GBS kernel density estimators (bias, variance and mean integrated squared error) are shown. Second, the choice of bandwidth is investigated by adopting the popular cross-validation technique. Finally, the performances of the MBC estimators based on GBS kernels are illustrated by a simulation study, followed by a real application for nonnegative heavy tailed (HT) data. In general, in terms of integrated squared bias (ISB) and integrated squared error (ISE), the proposed estimators outperform the standard GBS kernel estimators. [ABSTRACT FROM AUTHOR]

The basic framework of MANETs relies on best effort delivery of data and does not make any promises regarding assuring Reliability or Quality of Services. Seeing today's demand of multimedia applications and need of being always connected with or without internet is constantly attracting the researchers to evolve the MANETs (Mobile Ad hoc Networks) in order to assure the guarantee of services in terms of quality. In this paper the authors have critically examined the basic AODV a reactive routing protocol of MANET, with all its positive and negative characteristics. AODV (Ad hoc On Demand Distance Vector) is also examined for Quality of Service (QoS) provisioning. In this paper to support QoS, a Reliability aware variant of AODV is proposed. This reliability aware variant of AODV (RA-AODV) is based on conferring stability to routes. The chosen routes are constrained with End-to-End Delay and Bandwidth parameters to provide quality services to application layer. After that to enhance the reliability speed of intermediate nodes is taken into account . If node moves with slow speed stability of route is not hampered but if not, high speed node has to adjust some of its neighbouring node which can act on its behalf as a part of ongoing route part. An extensive simulation performed on basic AODV, MAODV (Modified-AODV constrained with EED and Bandwidth only, no speed parameter considers) and RA-AODV (Reliability Assured AODV) is tabulated and presented graphically in terms of PDR (Packet Delivery Ratio), Throughput and EED (End-to-End Delay) based on Mobility. [ABSTRACT FROM AUTHOR]

Objectives. We investigated whether differences in formants and their bandwidths, previously reported comparing small sample population of healthy individuals and patients with obstructive sleep apnea (OSA), are detected on a larger population representative of a clinical practice scenario.We examine possible indirect or mediated effects of clinical variables, which may shed some light on the connection between speech and OSA. Study Design. In a retrospective study, 241 male subjects suspected to suffer from OSAwere examined. The apneahypopnea index (AHI) was obtained for every subject using overnight polysomnography. Furthermore, the clinical variables usually reported as predictors of OSA, body mass index (BMI), cervical perimeter, height, weight, and age, were collected. Voice samples of sustained phonations of the vowels /a/, /e/, /i/, /o/, and /u/ were recorded. Methods. Formant frequencies F1, F2, and F3 and bandwidths BW1, BW2, and BW3 of the sustained vowels were determined using spectrographic analysis. Correlations among AHI, clinical parameters, and formants and bandwidths were determined. Results. Correlations between AHI and clinical variables were stronger than those between AHI and voice features. AHI only correlates poorly with BW2 of /a/ and BW3 of /e/. A number of further weak but significant correlations have been detected between voice and clinical variables. Most of them were for height and age, with two higher values for age and F2 of /o/ and F2 of /u/. Only few very weak correlations were detected between voice and BMI, weight and cervical perimeter, wich are the clinical variables more correlated with AHI. Conclusions. No significant correlations were detected between AHI and formant frequencies and bandwidths. Correlations between voice and other clinical factors characterizing OSA are weak but highlight the importance of considering indirect or mediated effects of such clinical variables in any research on speech and OSA. [ABSTRACT FROM AUTHOR]

Nowadays, several interesting patch antenna structure is proposed. In this paper, we are proposing a new rectangular structure in the form of a dollar-symbole, fed by a microstrip line is made with FR4 substrate, a thickness of 1.6 mm, and a relative permittivity of 4.4. The ground plane on the antenna is printed, while contain two slots. The resulting antenna has been found to possess a compact size of 30 mm × 30 mm, and suitable for wireless local area network (WLAN). Two resonant frequencies are obtained by the proposed antenna. The low-band resonant frequency is located at about 2.4 GHz, with -10 dB impedance bandwidth from about 1.9 GHz to 3 GH, and the high-band resonant frequency is located at about 8.8 GHz, with -10 dB impedance bandwidth from about 7.6 GHz to 10 GHz. In the first part, a comparison study of a patch antenna with slots and without slots is proposed; in the second part, the study of antenna parameters which affect dimensions is presented. [ABSTRACT FROM AUTHOR]

The dynamics of chaotic behavior of semiconductor laser diode with optical feedback from single mode fiber loop mirror has been experimentally studied. In the represented configuration the feedback strength was constant while the control parameter with laser injection current was variable, we found a wide range of optical intensity oscillation dynamics such as limit cycles, quasiperiodic and chaos oscillations. These dynamics were analyzed by time series and their extracted FFT power spectrums, phase diagrams (attractors), inter-spike intervals (ISI), these measurements enhanced by bifurcation diagram which clarified the chaotic regimes. Efficient bandwidth of chaotic signals has been calculated and observed to be increased with injection current. The complexity of chaotic system was measured by Shannon’s entropy function. [ABSTRACT FROM AUTHOR]

This paper is concerned with the design and manufacture of 4G patch antenna with the newly introduced artificial materials known as artificial magnetic surfaces or high impedance surface (HIS). The use of HIS for antenna performance enhancement is growing at a rapid pace. In this article a modified form of HIS is presented and successfully integrated with antenna for improved performance under low profile limitation. Frequency of operation is taken to be The industrial, scientific and medical (ISM) ISM 5.8 GHz and antenna parameters which are compared here are: Reflection Coefficient S 11 (dB), Radiation Pattern, Gain, Directivity and Bandwidth. Considerable amounts of improvements have been noticed with the use of HIS. [ABSTRACT FROM AUTHOR]

This paper is concerned with the design and manufacture of 4G patch antenna with the newly introduced artificial materials known as artificial magnetic surfaces or high impedance surface (HIS). The use of HIS for antenna performance enhancement is growing at a rapid pace. In this article a modified form of HIS is presented and successfully integrated with antenna for improved performance under low profile limitation. Frequency of operation is taken to be The industrial, scientific and medical (ISM) ISM 5.8 GHz and antenna parameters which are compared here are: Reflection Coefficient S 11 (dB), Radiation Pattern, Gain, Directivity and Bandwidth. Considerable amounts of improvements have been noticed with the use of HIS. [ABSTRACT FROM AUTHOR]

Rhombus Shaped Reconfigurable microstrip antenna is designed to operate at 1.74GHz. The proposed antenna is a Rhombus shaped microstrip antenna which gives a good size reduction with good impedance bandwidth in terms of with and without capacitor. The Designed antenna is expected to reduction in size and increase in Bandwidth. The Simulation is carried out by using IE3D software and practical results are measured by Vector Network analyzer. Comparative analysis has made between with and without capacitor as a lumped element. The size reduction of Rhombus shaped Reconfigurable microstrip antenna with capacitor gives best possible size reduction of 75.95% with overall bandwidth 86MHz. Acceptable agreement is obtained between the simulated and measured antenna performance parameter. [ABSTRACT FROM AUTHOR]

The optimal tracking performance of multiple-input multiple-output (MIMO) discrete-time networked control systems with bandwidth and coding constraints is studied in this paper. The optimal tracking performance of networked control system is obtained by using spectral factorization technique and partial fraction. The obtained results demonstrate that the optimal performance is influenced by the directions and locations of the nonminimum phase zeros and unstable poles of the given plant. In addition to that, the characters of the reference signal, encoding, the bandwidth and additive white Gaussian noise (AWGN) of the communication channel are also closely influenced by the optimal tracking performance. Some typical examples are given to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

High-speed I/O channels require adaptive techniques to optimize the settings for filter tap weights at decision feedback equalization (DFE) read channels to compensate for channel inter-symbol interference (ISI) and crosstalk from multiple adjacent channels. Both ISI and crosstalk tend to vary with channel length, process, and temperature variations. Individually optimizing parameters such as those just mentioned leads to suboptimal solutions. We propose a joint optimization technique for crosstalk cancellation (XTC) at DFE to compensate for both ISI and XTC in high-speed I/O channels. The technique is used to compensate for between 15.7 dB and 19.7 dB of channel loss combined with a variety of crosstalk strengths from 60 mVp-p to 180 mVp-p adaptively, where the transmit non-return-tozero signal amplitude is a constant 500 mVp-p. [ABSTRACT FROM AUTHOR]

Internet of Things is based on the identification of real-world objects in a unique way that interconnects them by means of communication interfaces. Such a simple idea allows the emergence of a huge number of new applications in almost any domain of knowledge. One of the most prominent areas of application is road vehicles, which currently have, on average, more than 50 sensors inside and which information can be accessed through a standard protocol. With this, vehicles have become real smart objects that can interact with other objects or any software system. To allow that, our previous work focused on proposing and developing the Vitruvius platform, where users with no programming knowledge can design and quickly generate Web applications based on the real-time data consumption from interconnected vehicles. The problem is that the sending of such information is out of control, being unable to filter out when the best time to send the information is and what information should be sent at any moment in order to minimize the resource consumption of the mobile device that acts as a bride between the vehicle and the database in which all the information is stored. Thus, in this work we propose a fuzzy algorithm that allows to optimize the resources that are used by real-time applications that constantly send data while maintaining data quality, contextualized in vehicle sensor tracking systems and the applications that can be built above them. [ABSTRACT FROM AUTHOR]

In this paper, modelling and control of an elastic actuator for rehabilitation robots are investigated. First, the required performance of the actuator is determined, and then a model of the actuator is proposed. Further, a control algorithm is presented to meet the required performance specifications. The control algorithm consists of an external PID torque controller and an internal PI speed Controller. Experimental tests are performed on the actuator to evaluate the actuator performance. First, an accuracy evaluation test is performed on the actuator to calibrate the torque measured by the spring. The results exhibit the spring's linear characteristics and the capability of torque measurement. Second, the bandwidth of the actuator is measured through sinusoidal input. The results show that the actuator is capable of delivering the required torque in the frequency range of rehabilitation. Third, an impedance measurement test is performed on the actuator indicating that it is capable of exerting the lowest and/or highest resistance on patient movement if required. As a result, it is shown that the proposed actuator can satisfy the whole rehabilitation requirements appropriately. [ABSTRACT FROM AUTHOR]