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With the development of synchrophasor measurement techniques, ambient signal-based load modeling is recently proposed to track the time-varying characteristics of power loads. On this basis, the hardware realization of this approach, which includes the local load modeling devices and the data center, is proposed and tested with the field measurement data from China Southern Power Grid. In this way, practical load model parameters can be identified from field measurement data both online and offline by the hardware system. To begin with, the hardware system, which is the first realization of an ambient signal-based load modeling algorithm, offers sufficient field measurements for load modeling. Then, the identification results of the field measurements verify the effectiveness of the ambient signal-based load modeling algorithm. Besides, the identified load model parameters for different substations during different times demonstrate the time-varying and the distributed characteristics of power loads. [ABSTRACT FROM AUTHOR]

Considering the complexity of wireless sensor network (WSN) coverage problems, which include many variables and a large continuous search space, a WSN coverage optimization method based on an improved artificial bee colony (ABC) algorithm with teaching strategy is proposed in this paper. ABC, which is good at exploration but poor at exploitation, is improved by introducing a teaching strategy in teaching-learning-based optimization (TLBO) that has a rapid convergence but is easily trapped in a local optima. Thus, the proposed algorithm combines the advantages of ABC strong global search ability and TLBO rapid convergence. In addition, to retain the diversity and eliminate the parameter limit in ABC, a dynamic search update strategy is introduced instead of the scout bee phase of ABC. In addition to preliminary examinations with a number of benchmark functions, the performance of the algorithm is verified by solving a complicated wireless sensor network coverage problem. The simulation results verify that the proposed algorithm achieves better balance between global and local search compared with other state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

The growing demand for high-performance ultra-high-definition video coding leads to H.265/high-efficiency video coding (HEVC), where the increased computational complexity and data/timing dependence hinder its coding throughput. To address these challenges, this paper presents four algorithm adaptations and a fully parallel hardware architecture for an H.265/HEVC intra encoder. To the best of our knowledge, this is the first fully parallel H.265/HEVC intra encoder. This design supports 35 prediction modes and all coding tree unit partitions. All PUs are independently processed in four prediction engines for high parallelism. An appropriate set of intra prediction modes, RDO candidates, and CABAC rate estimate instances is assigned to each prediction engine, where internal computational tasks are pipelined and scheduled to maximize the processing throughput. Compared with the HM-15.0 software, the proposed algorithm adaptations lead to a reduction of 27% in computational workload, while the average BD-rate and BD-PSNR are 4.39% and −0.21 dB, respectively. This BD-rate is lower than the existing designs with the same video resolution. FPGA implementation of the proposed design shows that it operates at 120 MHz and supports 45 fps of 1080P video sequences using 201-K logic elements and 120-KB on-chip SRAM. ASIC implementation of the proposed design in TSMC 90-nm technology shows that its clock frequency reaches 320 MHz with a hardware gate count of 2288 K, and that it supports real-time encoding of 30 fps of 4-K video sequences. Compared with the state-of-the-art designs, our proposed design demonstrates advantages in computational complexity, bit rate, video quality, throughput, reliability, and flexibility. [ABSTRACT FROM AUTHOR]

High computational complexity and heavy data/timing dependency in high efficiency video coding (HEVC) hinder the throughput of video encoding. In order to address both design challenges, we present high-performance algorithm adaptations and high-throughput hardware architecture for the HEVC intra encoders. Particularly, the chroma intra prediction includes the derived luma mode, which greatly improves the worst-case video compression performance. Compared with the HM-15.0 reference software, the proposed algorithms reduce the computational workload by 22%, while the average BD-Rate and BD-PSNR for classes A-F and 4K are 2.79% and −0.13 dB, respectively. This BD-Rate is lower than existing designs in the literature with the same video resolution. The field-programmable gate array (FPGA) implementation of proposed design shows it operates at 120 MHz and supports 45 f/s of 1080P video sequences using 196K logic elements and 127-KB on-chip SRAM. The application-specified integrated circuit (ASIC) implementation of the proposed design in TSMC 90 nm technology shows that its clock frequency reaches 320 MHz with a hardware gate count of 2186K and power consumption of 290 mW, and it supports real-time encoding of 4K videos at 30 f/s. [ABSTRACT FROM AUTHOR]

Sustainable scheduling problems have attracted great attention from researchers and enterprises. Sustainable scheduling should simultaneously consider economic, environmental and social impacts. However, to date, most studies on sustainable scheduling problems have emphasized the balance between the economy (e.g., makespan) and the environment (e.g., energy consumption or carbon emissions). Noise pollution is an important social issue and harmful to human health, however, it was ignored in most previous studies. Thus, this study investigates a welding shop scheduling problem (WSSP) that considers noise pollution alongside more common energy consumption and productivity issues. The studied WSSP is unique because multiple welders could simultaneously carry out the same task. First, we present a new mathematical model of the multi-objective WSSP. A novel hybrid multi-objective grey wolf algorithm (HMOGWO) is then designed. A new local search strategy based on the problem's properties is proposed to improve exploitation capability of the HMOGWO. In addition, a new energy saving strategy is presented to extend the operational life span of welders and promote energy efficiency. Finally, to demonstrate the effectiveness of the HMOGWO and the new energy saving strategy, we compare our proposal with other multi-objective optimization algorithms through comparison experiments. The results indicate that the proposed HMOGWO and energy saving strategy are superior to the competitors on this problem. Additionally, this method is successfully applied to a real-world case. [ABSTRACT FROM AUTHOR]

• Addressing the reconfigurability and grouped families in the DFSP. • Proposing a MILP model of the addressed problem. • Proposing dynamic solution encoding and decoding strategies. • Integrating a nested search strategy into the VND. • Good performance of the proposed approaches on two sets of instances. Inspired by a real-world cellular manufacturing system for processing printed circuit boards (PCBs), this study addresses a reconfigurable distributed flowshop scheduling problem (RDFGSP), where the flowline is considered as a cell and a complete process includes two flows through the flowlines. The characteristics of the RDFGSP lie in the reconfigurability of the flowlines and the families with grouped jobs. To solve this problem, at the two flows the family assignment part and sequence part (including family sequence and job sequence) are all required to be addressed. To solve the problem, a mixed integer linear programming (MILP) model is first developed, which can solve the small-scaled instances to optimality. Since the NP-hard property of the problem, a nested variable neighborhood descent (NVND) algorithm is developed. Its core ideas lie in the dynamic solution encoding and decoding strategies and the specially designed nested loops, including the external and internal loops. In the external loop, the solution encoding and decoding only consider the sequence part, and the family assignment part is conceived using the machine property in the decoding process. The internal loop is triggered when a decoding process in the external loop is completed, where the family assignment part and sequence part are all considered. In addition, a collaborative process and a restart strategy are employed to guarantee the global search capability. In the experimental study, the iterated F-Race (I/F-Race) is used to help determine the algorithm parameters with minimum user intervention. Comprehensive computational results demonstrate that the proposed algorithm outperforms the math solver CPLEX and other state-of-the-art metaheuristics. [ABSTRACT FROM AUTHOR]

This paper introduces a new discrete time continuous wavelet transform (DTCWT)-based algorithm, which can be implemented in real time to quantify and compensate periodic error for constant and non-constant velocity motion in heterodyne displacement measuring interferometry. It identifies the periodic error by measuring the phase and amplitude information at different orders (the periodic error is modeled as a summation of pure sine signals), reconstructs the periodic error by combining the magnitudes for all orders, and compensates the periodic error by subtracting the reconstructed error from the displacement signal measured by the interferometer. The algorithm is validated by comparing the compensated results with a traditional frequency domain approach for constant velocity motion. The algorithm demonstrates successful reduction of the first order periodic error amplitude from 4 nm to 0.24 nm (a 94% decrease) and a reduction of the second order periodic error from 2.5 nm to 0.3 nm (an 88% decrease). The algorithm also reduces periodic errors for non-constant velocity motion overcoming limitations of existing methods. [ABSTRACT FROM AUTHOR]

This paper is concerned with the scheduling of Electrical Multiple Units (EMUs) under the condition of their utilization on one sector or within several interacting sectors. Based on the introduction of the train connection graph which describes the possible connection relationship between trains, the integer programming model of EMU circulation planning is constructed. In order to analyzing the resolution of the model, a heuristic which shares the characteristics with the existing methods is introduced first. This method consists of two stages: one is a greedy strategy to construct a feasible circulation plan fragment, and another is to apply a stochastic disturbance to it to generate a whole feasible solution or get a new feasible solution. Then, an exact branch and bound method which is based on graph designing is proposed. Due to the complexity, the lower bound is computed through a polynomial approximation algorithm which is a modification from the one solving the degree constraint minimum 1-tree problem. Then, a branching strategy is designed to cope with the maintenance constraints. Finally, we report extensive computational results on a railway corridor in which the sectors possess the basic feature of railway networks. [ABSTRACT FROM AUTHOR]

Simple Summary: This study introduces a CT-based 3D reconstruction algorithm for measuring resection margins post sublobar resection in lung cancer patients. It aims to enhance accuracy and reproducibility, addressing the limitations of gross margin measurement. The findings show feasibility with a target registration error of <2.5 mm. This approach could revolutionize lung cancer treatment, facilitating prompt identification of patients with inadequate resection margins for timely post-operative adjuvant therapies. Sublobar resection has emerged as a standard treatment option for early-stage peripheral non-small cell lung cancer. Achieving an adequate resection margin is crucial to prevent local tumor recurrence. However, gross measurement of the resection margin may lack accuracy due to the elasticity of lung tissue and interobserver variability. Therefore, this study aimed to develop an objective measurement method, the CT-based 3D reconstruction algorithm, to quantify the resection margin following sublobar resection in lung cancer patients through pre- and post-operative CT image comparison. An automated subvascular matching technique was first developed to ensure accuracy and reproducibility in the matching process. Following the extraction of matched feature points, another key technique involves calculating the displacement field within the image. This is particularly important for mapping discontinuous deformation fields around the surgical resection area. A transformation based on thin-plate spline is used for medical image registration. Upon completing the final step of image registration, the distance at the resection margin was measured. After developing the CT-based 3D reconstruction algorithm, we included 12 cases for resection margin distance measurement, comprising 4 right middle lobectomies, 6 segmentectomies, and 2 wedge resections. The outcomes obtained with our method revealed that the target registration error for all cases was less than 2.5 mm. Our method demonstrated the feasibility of measuring the resection margin following sublobar resection in lung cancer patients through pre- and post-operative CT image comparison. Further validation with a multicenter, large cohort, and analysis of clinical outcome correlation is necessary in future studies. [ABSTRACT FROM AUTHOR]

Due to transmission impairments, optical regeneration is needed to extend the length of a lightpath beyond its transparent length. Spare transmitter (Tx) and receiver (Rx) modules in an optical network node can be used for optical regeneration. A Max-spare algorithm for locating the regeneration nodes for a lightpath is proposed and compared with a Greedy algorithm in conjunction with two routing algorithms, namely, wavelength weighted (WW) and length weighted (LW) routing algorithms. Through simulation we find that significant number of lightpaths that cannot be established due to the violation of transparent length can be established if the regeneration algorithm is used to select transit nodes that have spare Tx and Rx for 3R regeneration. The translucent optical network with limited number of transceivers can still perform close to a transparent optical network with full set of transceivers. We find that for the same routing algorithm, the Max-spare algorithm yields better results than the Greedy algorithm. In addition; for the same regeneration nodes selection algorithm, the WW algorithm has better performance than the LW algorithm. [Copyright &y& Elsevier]

Highlights • In this work, single channel 100 Gbit/s PAM4 transmission at O band is experimentally studied based on low cost intensity modulation and direct detection (IM-DD). • By the use of advanced digital signal processing algorithms, we successfully achieved a receiver sensitivity of −17.3 dBm at 7% HD-FEC threshold of 3.8E-3 over 40 km un-amplified SSMF transmission with 17 GHz (3 dB bandwidth) commercial EML and APD. • To the best of author's knowledge, we hereby report the best receiver sensitivity for 100 Gbit/s/λ IM-DD system. Abstract Single channel 100 Gbit/s PAM4 transmission at O band is experimentally studied based on low cost intensity modulation and direct detection (IM-DD). By the use of advanced digital signal processing algorithms, we successfully achieve a receiver sensitivity of −17.3 dBm at 7% HD-FEC threshold of 3.8E-3 over 40 km un-amplified SSMF transmission with 17 GHz (3 dB bandwidth) commercial electric absorption modulated laser (EML) and avalanche photodiode (APD). To the best of author's knowledge, we hereby report the best receiver sensitivity for 100 Gbit/s/λ IM-DD system. Due to the low cost and high sensitivity merits, the proposed scheme will be a promising way for high speed short-haul optical transmissions in the future. [ABSTRACT FROM AUTHOR]

Based on the analysis of the limitations of traditional compensation methods for analog temperature compensated crystal oscillators (ATCXOs), a new compensation algorithm and compensation network for ATCXOs are proposed in this paper. According to the frequency-temperature characteristics of AT-cut quartz crystals, the gain-temperature characteristics of voltage control crystal oscillators (VCXOs) are firstly derived and approximated by cubic functions. To improve the gain-temperature characteristics of ATCXOs, a quartic compensation algorithm and network are derived using curve fitting technique. A proposed design is implemented using 0.40 µm BCD process. Chip measurement results show that the frequency-temperature stability is within ±0.45 ppm over a temperature range of −40 °C to 85 °C. The phase noise levels are −87 dBc/Hz, −113 dBc/Hz, −137 dBc/Hz, and −152 dBc/Hz at 10 Hz, 100 Hz, 1 kHz, and 10 kHz frequency offset of 26 MHz AT-cut crystal, respectively. Compared with existing ATCXO designs in the literature, our proposed ATCXO chip improves the frequency-temperature stability by at least 55%, while maintaining a similarly low level of phase noise. [ABSTRACT FROM AUTHOR]

• An ultrasound diagnosis of breast cancer using a flexible ultrasound transducer is proposed. • A new mathematical model was established for ultrasound diagnosis of breast cancer. • Tumors closer to the flexible ultrasound array show lower visual resolution in the ultrasound image. Breast cancer is a very common malignant tumour that typically occurs in women aged 35–70 years (accounting for 85% of patients). Recently, it has been appearing in younger women as well. Traditional ultrasonic transducers usually use a fixed array, which avoids the radiation from mammography, has a low cost, and can be used for repeated testing. This substantially benefits the clinical diagnosis of breast cancer. However, the fixed transducer-array diagnosis process exerts considerable pressure on the human body, which can easily cause mass displacement or unnecessary pain. Therefore, ultrasound breast cancer diagnosis without compression has attracted attention. In this study, we used a flexible ultrasonic array to record the ultrasound information of the mass, and proposed a mathematical model suitable for breast-cancer diagnosis. Then, we used a self-shape–estimation algorithm to obtain a two-dimensional (2D) ultrasound image of the breast cancer. The algorithm was tested with simulated and experimental array data, and its performance was evaluated according to the tumour location. The surface-shape error obtained through the numerical simulation was less than 0.8 mm, and the deviation in the estimated mass position was less than 1.24 mm. The tumour location was also obtained experimentally in a breast-cancer model. Therefore, the method proposed in this paper can realize ultrasound diagnoses and represents a new diagnostic tool for breast cancer. [ABSTRACT FROM AUTHOR]