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Copyright of Journal of Wildland Fire Science is the property of Journal of Wildland Fire Science Editorial Office 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.)

This study aims to analyze how good and efficient the low-cost carriers' connectivity is at their major airports by studying one of the largest low-cost carriers in the world, AirAsia Group. Weighted Connectivity Ratio is used in the calculation, applied with slight modifications to suit the operations of low-cost carriers at their airports. The results reveal that some airlines have very good connectivity, even when it is compared to the connectivity of several big full-service carriers in Europe. This research brings a novelty in the form of an analysis of connectivity of low-cost carriers, considering that most of the previous research only focused on the connectivity of full-service carriers that implement a hub-and-spoke strategy. This is important because low-cost carriers are currently present with a very rapid growth as an alternative flight option that is more affordable for passengers in addition to full-service carriers that have previously dominated the aviation market. [ABSTRACT FROM AUTHOR]

Suitable trajectories with minimum execution time are essential for an industrial robot to enhance productivity in pick and place operations. A novel point-to-point trajectory planning algorithm (PTPA) is proposed to improve the motion efficiency of industrial robots. The jerk profile for a trajectory model is determined by five intervals and the jerk constraint. According to the kinematic constraints and two shape coefficients, a velocity threshold and three displacement thresholds are calculated for an individual joint to transfer the proposed jerk motion profile into four specific profiles. The optimal trajectory model of the joint is developed for the minimum-time and jerk-continuous trajectory via the performance evaluation with the input displacement and three displacement thresholds. Moreover, time-based motion synchronization for all joints is taken into account in PTPA to decrease unnecessary burdens on the actuators. The simulations illustrate that the execution time by PTPA is more efficient than that by other techniques. The experiments of a point-to-point application on a real six-axis industrial robot show that the absolute errors at the end of the motion for all joints are within 0.04°. These results prove that PTPA can be an effective point-to-point trajectory planner for industrial robots [ABSTRACT FROM AUTHOR]

The high cost of an energy storage system (ESS) is a barrier to its use. This paper proposes a risk-based virtual ESS (VESS) service strategy for prosumers. The basic concept of the VESS service is to logically refer to a physical ESS by multiple users. The VESS service can install ESS with a larger capacity compared to the case of installing ESS individually. Therefore, the VESS reduces the cost barrier through economies of scale. Moreover, ESS is not always being utilized at its maximum in the VESS service. Considering the risk, a VESS can offer a greater capacity than an installed ESS capacity. In this paper, the VESS service model suggested considers not only the economic benefit of increasing the VESS installation capacity but also the value at risk arising from servicing a greater capacity. The VESS service problem is formulated as a convex problem according to the VESS installation capacity and service price by applying stochastic approximation and is optimally solved using the gradient descent method in an iterative manner. The simulation results demonstrate that, when the proposed service strategy is used, the service provider that considers the risk achieves a significantly greater economic benefit of around 30% for the 128-prosumer pair case as compared to the one that does not consider risk. The benefit of the prosumer is increased by approximately 3.5% for the 128-prosumer pair case because the mismatched quantity is reduced during the peer-to-peer energy transaction. In addition, it is discussed how the proposed VESS service strategy achieves benefit through unit ESS cost reduction by the economics of scale and achieves increased service capacity with the multi-user diversity gain of participants. [ABSTRACT FROM AUTHOR]

Background: The transiliac-transsacral screw placement is a clinical challenge for surgeons. This study explored a point-to-point coaxial guide apparatus assisting the transiliac-transsacral screw insertion and aimed to investigate the feasibility and accuracy of the guide apparatus in the treatment of posterior ring unstable pelvic fracture compared with a free-hand technique. Methods: A retrospective study was performed to evaluate patients treated with transiliac-transsacral screws assisted by the point-to-point coaxial guide apparatus or free-hand technique. The intraoperative data of operative time and radiation exposure times were recorded. Postoperative radiographs and CT scans were performed to scrutinize the accuracy of screws position. The quality of the postoperative fracture reduction was assessed according to Matta radiology criteria. The pelvic function was assessed according to the Majeed scoring criteria at 6 months postoperatively. Results: From July 2017 to December 2019, a total of 38 patients were included in this study, 20 from the point-to-point guide apparatus group and 18 from the free-hand group. There were no significant differences between the two groups in gender, age, injury causes, pelvic fracture type, screws level, and follow-up time (P > 0.05). The average operative time of the guide apparatus group for each screw was significantly less than that in the free-hand group (25.8 ± 4.7 min vs 40.5 ± 5.1, P < 0.001). The radiation exposure times were significantly lower in the guide apparatus group than that in the free-hand group (24.4 ± 6.0 vs 51.6 ± 8.4, P < 0.001). The intraosseous and juxtacortical rate of screw placement (100%) higher than in the free-hand group (94.4%). Conclusion: The point-to-point coaxial guide apparatus is feasible for assisting the transiliac-transsacral screw in the treatment of posterior unstable pelvic fractures. It has the advantages of simple operation, reasonable design and no need for expensive equipment, and provides an additional surgical strategy for the insertion of the transiliac-transsacral screw. [ABSTRACT FROM AUTHOR]

Interference in Wireless Sensor Network (WSN) predominantly affects the performance of the WSN. Energy consumption in WSN is one of the greatest concerns in the current generation. This work presents an approach for interference measurement and interference mitigation in point to point network. The nodes are distributed in the network and interference is measured by grouping the nodes in the region of a specific diameter. Hence this approach is scalable and isextended to large scale WSN. Interference is measured in two stages. In the first stage, interference is overcome by allocating time slots to the node stations in Time Division Multiple Access (TDMA) fashion. The node area is split into larger regions and smaller regions. The time slots are allocated to smaller regions in TDMA fashion. A TDMA based time slot allocation algorithm is proposed in this paper to enable reuse of timeslots with minimal interference between smaller regions. In the second stage, the network density and control parameter is introduced to reduce interference in a minor level within smaller node regions. The algorithm issimulated and the system is tested with varying control parameter. The node-level interference and the energy dissipation at nodes are captured by varying the node density of the network. The results indicate that the proposed approach measures the interference and mitigates with minimal energy consumption at nodes and with less overhead transmission. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zhengzhou University (Natural Science Edition) is the property of Journal of Zhengzhou University (Natural Science Edition) Editorial Office 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.)

A novel high-speed wireless transmitter (TX) architecture is presented that directly transforms incoming data bits into high-order $4^{M}$ -quadrature amplitude modulation (QAM) constellation by adding multiple quadrature phase shift keying (QPSK) signals with appropriate amplitude ratios. The costly high-speed digital-to-analog converters (DACs) in conventional TXs are thus completely avoided, resulting in a highly integrated solution amenable to ultra-high speeds and operating frequencies. Design tradeoffs are analyzed in detail. Based on this article, a TX prototype at 115-GHz carrier frequency implementing the 16QAM direct-modulation scheme is fabricated in a 180-nm SiGe BiCMOS process ($f_{\text {MAX}} = 270$ GHz). Wireless testing at a 20-cm distance with 25-dBi horn antennas on both transmitting and receiving side measures 20-Gb/s data rate with an error vector magnitude (EVM) of −15.8 dB and modulated output power of +1 dBm. The TX consumes 520 mW of power and occupies 3.17 mm2 of active area. [ABSTRACT FROM AUTHOR]

Variable-length (VL) coding with feedback is a commonly used technique that can approach point-to-point Shannon channel capacity with a significantly shorter average codeword length than fixed-length coding without feedback. This paper uses the inter-frame coding of Zeineddine and Mansour, originally introduced to address varying channel-state conditions in broadcast wireless communication, to approach capacity on point-to-point channels using VL codes without feedback. The per-symbol complexity is comparable to decoding the VL code with feedback (plus the additional complexity of a small peeling decoder amortized over many VL codes) and presents the opportunity for encoders and decoders that utilize massive parallel processing, where each VL decoder can process simultaneously. This paper provides an analytical framework and a design process for the degree distribution of the inter-frame code that allows the feedback-free system to achieve 96% or more of the throughput of the original VL code with feedback. As examples of VL codes, we consider non-binary (NB) low-density parity-check (LDPC), binary LDPC, and convolutional VL codes. The NB-LDPC VL code with an 8-bit CRC and an average codeword length of 336 bits achieves 85% of capacity with four rounds of ACK/NACK feedback. The proposed scheme using shared incremental redundancy without feedback achieves 97% of that performance or 83% of the channel capacity. [ABSTRACT FROM AUTHOR]

Multicast-Broadcast over Single Frequency Network (MBSFN) technology, as introduced by the Long Term Evolution Advanced group, is expected to be part of the upcoming cellular systems offering resource efficiency to broadcast services. MBSFN transmission is suitable to serve multicast groups searching the same content. In addition, the fast emerging technology of femtocells networks and their hybrid nature can lead to efficient resource sharing between non-subscribed users when located inside their coverage. The focus of this manuscript is 2-fold; firstly, we have contacted simulation experiments to compare the MBSFN transmission with the traditional Point-To-Point transmission for various femtocell distributions and network topology changes; secondly, a novel multicast transmissions mechanism is proposed from non-subscribed users who exploit femtocells resources for broadcast services, without limiting user's data requirements. The simulation results lead to a significant system's performance in terms of average throughput, total capacity, and energy consumption. [ABSTRACT FROM AUTHOR]

Two fully integrated chipsets covering the entire E-band frequency range, 71–76/81–86 GHz, have been demonstrated. These designs, which were implemented in 0.13-\mu\m SiGe BiCMOS technology, use a sliding IF superheterodyne architecture. The receiver (Rx) chips include an image-reject low-noise amplifier, RF-to-IF mixer, variable gain IF amplifier (IF VGA), quadrature IF-to-baseband (BB) de-modulator, tunable BB filter, phase-locked loop (PLL) synthesizer, and a frequency quadrupler. At room temperature the Rx chips achieve a maximum gain of 73 dB, 6-dB noise figure, better than -\12-dBm input third-order intercept point, more than 65-dB dynamic range, and consume 600 mW for lower band (LB) (71–76 GHz) and higher band (HB) (81–86 GHz) alike. The transmitter (Tx) chips include a power amplifier, image reject driver, variable RF attenuators, power detector, IF-to-RF up-converting mixer, IF VGA, quadrature BB-to-IF modulator, PLL, and a frequency multiplier. The Tx chips achieve a power 1-dB compression point (P1dB) of 17.5/16.6 dBm, saturated power (Psat) of 20.5/18.8 dBm on a single-ended output, up to 39-dB gain with an analog controlled dynamic range of 30 dB, and consumes 1.75/1.8 W for the LB and HB, respectively. This state-of-the-art performance enables the usage of complex modulations and high-capacity transmission. [ABSTRACT FROM PUBLISHER]

The update of the rigid body transformation in the iterative closest point (ICP) algorithm is considered. The ICP algorithm is used to solve surface registration problems where a rigid body transformation is to be found for fitting a set of data points to a given surface. Two regions for constraining the update of the rigid body transformation in its parameter space to make it reliable are introduced. One of these regions gives a monotone convergence with respect to the value of the mean square error and the other region gives an upper bound for this value. Point-to-plane distance minimization is then used to obtain the update of the transformation such that it satisfies the used constraint. [ABSTRACT FROM AUTHOR]

In this paper, we study the performance of single carrier (SC) modulation with frequency-domain equalization (FDE) over underwater acoustic (UWA) channels. The underlying channels are time-varying intersymbol interference (ISI) channels, where time variation arises from the relative motion between the transceivers, which induces one or more Doppler scaling factors. We study two scenarios: a point-to-point (P2P) system, where each cluster of paths has its own distinct Doppler scaling factor, and a multiple access (MAC) system, where $M$ users communicate with a multiple-antenna common receiver in which each user has its own Doppler scaling factor. First, the maximum likelihood (ML) receiver is derived for both scenarios, and it is shown that a preprocessing stage is necessary to reduce the time variation; this is referred to as multiple resampling (MR). The proposed receiver consists of multiple branches where each branch corresponds to a cluster/user and performs frequency shifting and resampling followed by an integrator. Since the output of the MR stage is contaminated by ISI for P2P systems and ISI and interuser interference for MAC systems, an additional equalization stage is necessary, which is ideally the ML sequence detector (MLSD). Since the complexity of MLSD exponentially grows with the number of symbols per block, the alphabet size, and the number of users, a linear minimum-mean-square-error FDE equalizer is used instead. To further reduce the complexity, instead of resampling the received signal multiple times by different scaling factors, it is resampled only by one scaling factor, which is a function of all Doppler scaling factors. The resulting suboptimal preprocessing scheme is called single resampling (SR). Simulation results for uncoded systems show that MR outperforms its SR counterpart at the expense of some additional hardware complexity. Moreover, it is shown that SC-FDE is more resilient than orthogonal frequency-division multiplexing (OFDM) to the Doppler scaling effect in UWA channels at lower overall complexity for the MR case, whereas both have the same overall complexity for the SR case. [ABSTRACT FROM AUTHOR]

Purpose -- The purpose of this paper is to study the efficiency and financial situation of Spanish airlines by conducting a comparative analysis of those operating in hubs and those that employ the point-to-point system. Design/methodology/approach -- Data envelopment analysis and accounting rates are implemented to do so. Findings -- The results show that hubs do not result in the companies that use them being efficient. Instead, it is the charter, low-cost and private flight operators that best manage their resources. Originality/value -- The study makes a novel contribution to the literature, as there has been no research on Spanish airlines that compares the two types of operators (hubs and point to point). [ABSTRACT FROM AUTHOR]

We consider a random walk in a random potential on a square lattice of arbitrary dimension. The potential is a function of an ergodic environment and steps of the walk. The potential is subject to a moment assumption whose strictness is tied to the mixing of the environment, the best case being the i.i.d. environment. We prove that the infinite volume quenched point-to-point free energy exists and has a variational formula in terms of entropy. We establish regularity properties of the point-to-point free energy, and link it to the infinite volume point-to-line free energy and quenched large deviations of the walk. One corollary is a quenched large deviation principle for random walk in an ergodic random environment, with a continuous rate function. [ABSTRACT FROM AUTHOR]

Rational secret sharing was first introduced by Halpern and Teague (STOC, 2004). Since then, a series of works have focused on designing rational secret sharing protocols. However, most existing solutions can share only one secret at one secret sharing process. To share multiple secrets such as m secrets, the dealer must redistribute shares for m times. In addition, previous works assume existence of broadcast channel which is not realistic. Motivated by those problems, this paper proposes a rational multi-secret sharing scheme, which combines the secret sharing scheme with game theory. In the protocol, the problem of sharing multiple secrets is addressed, and there are multiple secrets to be shared during one secret sharing process. Furthermore, this work starts off by constructing a protocol in simultaneous broadcast networks, and then we emulate the broadcast channel over point-to-point networks. Based on a computational assumption, we show that rational players have no incentive to deviate from the protocol and every player can obtain multi-secret fairly. [ABSTRACT FROM AUTHOR]

The exploitation of the 60 GHz band is a very promising approach to fulfill the rapidly increasing data rate requirement of wireless indoor communication. One important 60 GHz application is the short-range point-to-point data transmission with Ultra-High-Rate (UHR, up to 10 Gbps) (Krone et al. in International Journal of Microwave and Wireless Technologies, , 189-200). The design of such high data rate systems is very challenging. Except for Analog-Front-End (AFE) and physical layer (PHY) designs, the Medium Access Control (MAC) layer design is also crucial for the achievable system throughput. Among the MAC functionalities, the acknowledgment (ACK) mechanism is a very important component affecting the transmission efficiency and reliability. In this paper, a Hybrid Dynamic Frame Aggregation and Block-Acknowledgment (HD-FABA) scheme is proposed, which enables large-scale frame aggregation and can achieve significant ACK overhead reduction compared to the existing schemes. A theoretical model is developed for throughput analysis, which is verified by packet-level simulation. Both theoretical- and simulation results show that the HD-FABA scheme allows a number of MAC parameters to be optimized according to the PHY conditions (e.g. BER), leading to much higher throughput than with the state-of-the-art scheme. [ABSTRACT FROM AUTHOR]

This paper presents an integrated-Stream Protocol (iSP) interface that is capable of high data rate operation with less signal lines for the next generation TFT-LCD application. An 8b/9b encoding technique is employed to synchronize the system without separate clock and control signal lines, and it achieves low overhead and electromagnetic interference (EMI) performance. In order to compensate the channel attenuation, the receiver is equipped with the equalizer function. The power consumption is effectively reduced by applying the transfer-impedance amplifier (TIA) receiver. The iSP interface has been verified on an 11.6-inch full-HD Chip-On-Glass (COG) TFT-LCD panel with 1.35Gbps data rate. Additionally, it could be operated at higher data rate up to 1.8Gbps on Chip-On-Board (COB) platform. [ABSTRACT FROM AUTHOR]

This paper presents an intra-panel interface that adopts a skew-less point-to-point mini-LVDS (SPPmL) using 240 Hz of driving technology. A differential data signal with an embedded code was applied between the timing controller (TCON) and column driver ICs (DICs) to synchronize the clock and data. The synchronization core circuit was based on a delay cell that eliminates clock and data skew problems. Power consumption was effectively reduced using a delay cell circuit lower than using a phase-locked loop (PLL) and a delay-locked loop (DLL) circuit. The proposed SPPmL interface was verified on a 65-in. full HD (1920times1080) TFT-LCD panel to achieve the high data transfer rate required for high-resolution LCD models. The measured results show that the maximum data rate is higher than 2.0 Gb/s. [ABSTRACT FROM AUTHOR]

A 2-Gb/s point-to-point intrapanel interface for thin-film-transistor liquid crystal display (TFT-LCD) is proposed by using only clock and data lines. Extra control lines are eliminated by sending the VSYNC code through the clock line at the start of the VBLANK time period and by sending the control commands through the data line at the end of the VBLANK time period. To reduce electromagnetic interference, the slew rate of the clock driver is reduced, and the frequency of clock signals is set to the subpixel (R/G/B) frequency (1/10 of the data rate). The clock line is cascaded between two adjacent receiver (RX) chips for a point-to-point interface. To generate an internal clock synchronized (deskewed) to the subpixel (R/G/B) boundary of incoming data at each RX, a single all-digital delay-locked loop (DLL) circuit is proposed to perform the combined operation of a DLL and a phase interpolator. This deskew operation is performed during the VBLANK period with periodic preamble data input (‘1111100000’). At the RX, a multiphase DLL follows the deskew DLL to generate 20-phase clocks for data sampling. 2-Gb/s data are transmitted through a series connection of a 100-cm-long flat flexible cable and a 50-cm-long FR4 microstrip line with a bit error rate less than 1e–12. The image test was successfully performed with a 42-in full-high definition 120-Hz LCD panel at 1.5 Gbps. The area and power consumption of RX chip is 0.35 \mm^2 and 52.4 mW at 2 Gbps with a 0.18- \mu\m complementary metal–oxide–semiconductor process and a 1.8-V supply. [ABSTRACT FROM PUBLISHER]

This paper investigates the impacts of competition and market uncertainty on airlines' network structures and capacity investment. The airlines choose their network structures and construct capacities while demands are unknown. After uncertainty is resolved, they determine the total number of seats to offer in each leg constrained by their capacities built earlier. We conclude that market uncertainty is the driving force of hub-and-spoke networks, whereas the market mean is the driving force of point-to-point networks. Which of the two countervailing forces dominates determines the equilibrium network structures. Moreover, we find that the airlines' total expected profits in the mixed equilibrium in which the airlines employ different networks are larger than in the pure hub-and-spoke network equilibrium in which each airline employs the hub-and-spoke network. However, the mixed equilibrium does not necessarily yield larger profits than the pure point-to-point equilibrium in which each airline employs the point-to-point network. [ABSTRACT FROM AUTHOR]

Traffic matrices are required inputs for many IP network management tasks, such as capacity planning, traffic engineering, and network reliability analysis. However, it is difficult to measure these matrices directly in large operational IP networks, so there has been recent interest in inferring traffic matrices from link measurements and other more easily measured data. Typically, this inference problem is ill-posed, as it involves significantly more unknowns than data. Experience in many scientific and engineering fields has shown that it is essential to approach such ill- posed problems via "regularization." This paper presents a new approach to traffic matrix estimation using a regularization based on "entropy penalization." Our solution chooses the traffic matrix consistent with the measured data that is information-theoretically closest to a model in which source/destination pairs are stochastically independent. It applies to both point-to-point and point-to-multipoint traffic matrix estimation. We use fast algorithms based on modern convex optimization theory to solve for our traffic matrices. We evaluate our algorithm with real backbone traffic and routing data, and demonstrate that it is fast, accurate, robust, and flexible. [ABSTRACT FROM AUTHOR]

We describe a DRAM interface operating at 36 Gb/s/pin implemented in 130-nm CMOS logic and 110-nm DRAM process technologies. It utilizes simultaneous bidirectional (SBD) signaling in a daisy-chained (repeated), point-to-point configuration to enable high performance scalable memory subsystems; and also provides direct attach capability for DRAMS to memory controllers or other logic devices. Source-synchronous strobes are used for data capture, minimizing strobe-to-data jitter. A low-jitter differential clock retimes the data at each DRAM on a per DIMM basis preventing jitter from accumulating in repeated data. The phase of this clock is adjusted on each DRAM to minimize the latency of the repeaters. 80 mW of total power is dissipated per DRAM I/O at 3.6 Gb/s. We present results from a system using both memory controller and DRAM repeater test chips. [ABSTRACT FROM AUTHOR]