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Fundraising Capacity of HIV/AIDS Community-Based Organizations in 3 Years (2017-2019) in Ho Chi Minh City, Vietnam
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作者 Tran Chi Thanh Pham Duc Trinh +2 位作者 Nguyen Duc Thanh Linus Olson Mattias Larsson 《World Journal of AIDS》 2020年第3期186-194,共9页
HIV/AIDS is still an important public health issue in Vietnam and other developing countries. In Vietnam, Community-based organizations (CBOs) were officially considered as the key partners to approach vulnerable grou... HIV/AIDS is still an important public health issue in Vietnam and other developing countries. In Vietnam, Community-based organizations (CBOs) were officially considered as the key partners to approach vulnerable groups at high risks of HIV infection since 2010. Funds for HIV/AIDS prevention and control are facing difficulties due to rapid reduction by international organizations, while domestic funding has not yet met the demand, especially funding for prevention and communication activities. Our study aimed to assess the fundraising capacity of several CBOs in Ho Chi Minh City, Vietnam and analyze the challenges that they are facing now and in future in their work of HIV/AIDS management for community. The 03 typical and representative CBOs (G3VN, Smile and Strong Ladies) were chosen in our cross-sectional descriptive study. The electronic questionnaire was about fundraising reports over 3 years (2017-2019), organization structure (staff, mission, strategies) and the advantages and disadvantages in fundraising. Funds received over the year increased in total, but unstable in each projects. To have more funds, CBOs must invest time and money to have professional staff in fundraising and writing proposals. To meet requirement and survive, some CBO shifted to social enterprises and faced many difficulties in laws when being treated like profit companies. In Vietnam context, the key challenges which affect the role of funding are including: 1) Legal status;2) Small scale;3) Capacity of fundraising (finding calls, writing competence proposals);4) Fewer funds on HIV/AIDS. In future, we should pay attention in scaling up and building fundraising capacity for CBOs in order to help them in applying for international funds in community projects or even in HIV/AIDS research for CBOs, social enterprises in the context of funds for nation-level phased out of Vietnam. 展开更多
关键词 CBO HIV/AIDS fundraising Ho Chi Minh City VIETNAM
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How much do social connections matter in fundraising outcomes?
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作者 Lihuan Guo Wei Wang +1 位作者 Yenchun Jim Wu Mark Goh 《Financial Innovation》 2021年第1期1706-1728,共23页
This study examines the role of social connections and network centrality in attracting funders to crowdfunding campaigns.We classify social connections as either external(e.g.,Facebook)or internal(e.g.,investing in o... This study examines the role of social connections and network centrality in attracting funders to crowdfunding campaigns.We classify social connections as either external(e.g.,Facebook)or internal(e.g.,investing in online platforms through resource exchange).Drawing from the 108,463 crowdfunding campaigns on the online platform Kickstarter from April 21,2009,to July 24,2019,we apply external linkages and online followers to estimate the effect of external social connections.We construct a digraph network for the internal social connections and use PageRank,HITS,and centrality to obtain the weights of the nodes.Next,we compare the performance change of several prediction algorithms by feeding social connection-related variables.This study has several findings.First,for external social connections,having more online followers improves the funding success rate of a campaign.Second,for internal social connections,only authority and degree in centrality positively affect the number of funders and the campaign’s financing progress among the weights of the nodes.Third,using social connection variables improves the prediction algorithms for funding outcomes.Fourth,external social connections exert greater funding outcomes than internal social connections.Fourth,entrepreneurs should extend their external social connections to their internal social connections,and network centrality expedites project financing.Fifth,the effect of social connections on fundraising outcomes varies among the campaign categories.Fundraisers who are online influencers should leverage their online social connections,notably for the project categories that matter. 展开更多
关键词 CROWDFUNDING Social connections Social networks Kickstarter fundraising Online influence
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How Does Online Fundraising Platform Promote Public Donation in China?-An Empirical Analysis From Tencent Fundraising Platform
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作者 XU Wen-wen ZHANG Lei 《Journalism and Mass Communication》 2017年第9期503-515,共13页
At present, the huge problem that China’s Non-profit Organizations are facing is the low efficiency of public fundraising. However, the newly appeared Online Fundraising Platform indicates some possibilities in ove... At present, the huge problem that China’s Non-profit Organizations are facing is the low efficiency of public fundraising. However, the newly appeared Online Fundraising Platform indicates some possibilities in overcoming the obstacle for public fundraising. Among which Tencent Online Fundraising Platform becomes the typical and the point cut of exploring Online Fundraising Platform Improving Efficiency Mechanism of public donation. Online Fundraising Platform is similar to the online United Way, relying on the advantages of the Internet and the united fundraising to build a ecosystem of public donation which has professional fundraising system, good charity atmosphere, excellent policy environment and crossover cooperation resources. And in which, many factors get improved in pubic donation influence factors system. For one thing, Charity atmosphere and policy environment can be shaped better. For another, the charities can transmit fundraising information in inexpensive and high-efficiency way, and must ensure the transparency of project and donation. Finally, it will be more convenient for donors to get charitable information, make donations and supervise the nonprofit organizations. 展开更多
关键词 Online fundraising Platform public donation influence factors system public donation improving efficiency mechanism Tencent Online fundraising Platform
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Jamming Assisted Covert Wireless Communication in Multi-Channel Systems
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作者 Che Bohan Sha Nan +2 位作者 Yang Weiwei Lu Xingbo Gao Chang 《China Communications》 SCIE CSCD 2024年第9期211-224,共14页
This paper investigates the jammerassisted multi-channel covert wireless communication(CWC)by exploiting the randomness of sub-channel selection to confuse the warden.In particular,we propose two sub-channel selection... This paper investigates the jammerassisted multi-channel covert wireless communication(CWC)by exploiting the randomness of sub-channel selection to confuse the warden.In particular,we propose two sub-channel selection transmission schemes,named random sub-channel selection(RSS)scheme and maximum sub-channel selection(MSS)scheme,to enhance communication covertness.For each proposed scheme,we first derive closed-form expressions of the transmission outage probability(TOP),the average effective rate,and the minimum average detection error probability(DEP).Then,the average effective covert rate(ECR)is maximized by jointly optimizing the transmit power at the transmitter and the number of sub-channels.Numerical results show that there is an optimal value of the number of sub-channels that maximizes the average ECR.We also find that to achieve the maximum average ECR,a larger number of subchannels are needed facing a stricter covertness constraint. 展开更多
关键词 covert wireless communication jamming multi-channel system
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A novel multi-channel porous structure facilitating mass transport towards highly efficient alkaline water electrolysis
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作者 Xinge Jiang Vasileios Kyriakou +6 位作者 Chen Song Xianbin Wang Sophie Costil Chunming Deng Taikai Liu Tao Jiang Hanlin Liao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期511-518,I0013,共9页
An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis(AWE)efficiency by optimizing the mass transport mechanisms.This effect becomes even more pronounced w... An advantageous porous architecture of electrodes is pivotal in significantly enhancing alkaline water electrolysis(AWE)efficiency by optimizing the mass transport mechanisms.This effect becomes even more pronounced when aiming to achieve elevated current densities.Herein,we employed a rapid and scalable laser texturing process to craft novel multi-channel porous electrodes.Particularly,the obtained electrodes exhibit the lowest Tafel slope of 79 mV dec^(-1)(HER)and 49 mV dec^(-1)(OER).As anticipated,the alkaline electrolyzer(AEL)cell incorporating multi-channel porous electrodes(NP-LT30)exhibited a remarkable improvement in cell efficiency,with voltage drops(from 2.28 to 1.97 V)exceeding 300 mV under 1 A cm^(-1),compared to conventional perforated Ni plate electrodes.This enhancement mainly stemmed from the employed multi-channel porous structure,facilitating mass transport and bubble dynamics through an innovative convection mode,surpassing the traditional convection mode.Furthermore,the NP-LT30-based AEL cell demonstrated exceptional durability for 300 h under 1.0 A cm^(-2).This study underscores the capability of the novel multi-channel porous electrodes to expedite mass transport in practical AWE applications. 展开更多
关键词 Alkaline water electrolysis Mass transport Bubble dynamics Innovative convection mode multi-channel porous structure
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Design of Cold-Junction Compensation and Disconnection Detection Circuits of Various Thermocouples and Implementation of Multi-Channel Interfaces Using Them-A Secondary Publication
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作者 Hyeong-Woo Cha 《Journal of Electronic Research and Application》 2024年第1期93-105,共13页
Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC... Cold-junction compensation(CJC)and disconnection detection circuit design of various thermocouples(TC)and multi-channel TC interface circuits were designed.The CJC and disconnection detection circuit consists of a CJC semiconductor device,an instrumentation amplifier(IA),two resistors,and a diode for disconnection detection.Based on the basic circuit,a multi-channel interface circuit was also implemented.The CJC was implemented using compensation semiconductor and IA,and disconnection detection was detected by using two resistors and a diode so that IA input voltage became-0.42 V.As a result of the experiment using R-type TC,the error of the designed circuit was reduced from 0.14 mV to 3μV after CJC in the temperature range of 0°C to 1400°C.In addition,it was confirmed that the output voltage of IA was saturated from 88 mV to-14.2 V when TC was disconnected from normal.The output voltage of the designed circuit was 0 V to 10 V in the temperature range of 0°C to 1400°C.The results of the 4-channel interface experiment using R-type TC were almost identical to the CJC and disconnection detection results for each channel.The implemented multi-channel interface has a feature that can be applied equally to E,J,K,T,R,and S-type TCs by changing the terminals of CJC semiconductor devices and adjusting the IA gain. 展开更多
关键词 R-type thermocouple(TC) Cold-junction compensation(CJC) TC disconnection detection multi-channel interface circuit Sensor interface
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Development of multi-channel observation and inversion for IP electrical sounding method 被引量:5
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作者 刘海飞 柳建新 +3 位作者 郭荣文 童孝忠 龚露 彭艳华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期816-823,共8页
In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are s... In order to improve the exploration effect of deep non-ferrous mineral resources, multi-channel observation methods for induced polarization (IP) electrical sounding data and their inversion imaging technology are studied. First of all, four multi-channel observation methods are developed based on conventional IP electrical method, namely three-electrode and four-electrode arrays of unilateral and bilateral current transmitting. Then the maximum smoothness constrained inversion method of the least squares sense for IP electrical sounding data is proposed, and the inversion software is programmed. Finally, the simulation and inversion results of geo-electrical model for the proposed observation methods are analyzed. And the comparison results show that three-electrode array of bilateral current transmitting gives the best result, but the intensity in field work is larger than others; unilateral three-electrode and four-electrode arrays give the better results. Taking detection results and convenience of field exploration work into consideration, these two methods are more suitable for practical application; bilateral observation method of four-electrode array is not suitable for the detection of the steep ore bodies. 展开更多
关键词 IP electrica-1 sounding multi-channel observation deep exploration inversion imaging
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Design of multi-channel data acquisition system based on LabVIEW and NI PXI-5105 被引量:4
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作者 解亚妮 张志杰 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第1期7-12,共6页
A data acquisition system based on LabVIEW and NI PXI-5105 is presented for multi-channel data acquisition. It can realize the functions of parameter setting, data acquisition and storage, waveform display and data an... A data acquisition system based on LabVIEW and NI PXI-5105 is presented for multi-channel data acquisition. It can realize the functions of parameter setting, data acquisition and storage, waveform display and data analysis using LabVIEW and NI-SCOPE device driver. The advantages of the system are that the setting is convenient, the operation is easy, the interface is friendly and the functions are practical. The experiment results show that the system has good stability and high reliability and is a powerful tool for multi-channel data acquisition. 展开更多
关键词 LABVIEW multi-channel data acquisition PXI-5105
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A maximum-independent-set-based channel allocation algorithm for multi-channel wireless networks
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作者 余旭涛 施小翔 曾绍祥 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期12-18,共7页
A channel allocation algorithm based on the maximum independent set is proposed to decrease network conflict and improve network performance. First, a channel allocation model is formulated and a series of the maximum... A channel allocation algorithm based on the maximum independent set is proposed to decrease network conflict and improve network performance. First, a channel allocation model is formulated and a series of the maximum independent sets (MISs) are obtained from a contention graph by the proposed approximation algorithm with low complexity. Then, a weighted contention graph is obtained using the number of contention vertices between two MISs as a weighted value. Links are allocated to channels by the weighted contention graph to minimize conflicts between independent sets. Finally, after channel allocation, each node allocates network interface cards (NICs) to links that are allocated channels according to the queue lengths of NICs. Simulations are conducted to evaluate the proposed algorithm. The results show that the proposed algorithm significantly improves the network throughput and decreases the end to end delay. 展开更多
关键词 wireless networks multi-channel channelaUocation maximum independent set
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基于Multi-Radio Multi-Channel传感器网络无冲突信道分配算法的研究 被引量:2
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作者 蔡凤丽 刘新永 《吉林工程技术师范学院学报》 2014年第5期95-96,共2页
为降低通信冲突和信道干扰,对Mult-i Radio Mult-i Channel传感器网络无冲突信道进行研究,结果证实在网络通信半径大于3倍的网络最大功率通信半径的前提下,Sensor节点规模满足2倍网络功率级数加1的环境下,网络无冲突信道分配的信道数达... 为降低通信冲突和信道干扰,对Mult-i Radio Mult-i Channel传感器网络无冲突信道进行研究,结果证实在网络通信半径大于3倍的网络最大功率通信半径的前提下,Sensor节点规模满足2倍网络功率级数加1的环境下,网络无冲突信道分配的信道数达到网络信道冲突图的最大值。文章通过对无冲突信道算法的运用,最终证实其可以有效地提高传感器网络的工作效率,大幅度提升网络的吞吐量。 展开更多
关键词 MULTI-RADIO multi-channel 传感器网络 无冲突信道信道分配
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A Novel Design of Efficient Multi-channel UART Controller Based on FPGA 被引量:10
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作者 HU Zhe ZHANG Jun LUO Xi-ling 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2007年第1期66-74,共9页
In traditional universal asynchronous receiver transmitter (UART) controller, the data transmission is inefficient and the data bus utilization ratio is low. A novel design is provided to solve these problems. The a... In traditional universal asynchronous receiver transmitter (UART) controller, the data transmission is inefficient and the data bus utilization ratio is low. A novel design is provided to solve these problems. The architecture of the system is introduced, the flow charts of data processing as well as the implementation state machine are also presented in detail. This paper is concluded by comparing the performance of this design, which is realized on field programmable gate army (FPGA) using Verilog hardware description language (HDL), with other traditional UART controllers. 展开更多
关键词 serial communication UART multi-channel FPGA
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Performance analysis of multi-channel order statistics detector for range-spread target 被引量:5
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作者 Shuwen Xu Penglang Shui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第5期689-699,共11页
The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optima... The problem of two order statistics detection schemes for the detection of a spatially distributed target in white Gaussian noise are studied.When the number of strong scattering cells is known,we first show an optimal detector,which requires many processing channels.The structure of such optimal detector is complex.Therefore,a simpler quasi-optimal detector is then introduced.The quasi-optimal detector,called the strong scattering cells’ number dependent order statistics(SND-OS) detector,takes the form of an average of maximum strong scattering cells with a known number.If the number of strong scattering cells is unknown in real situation,the multi-channel order statistics(MC-OS) detector is used.In each channel,a various number of maximums scattered from target are averaged.Then,the false alarm probability analysis and thresholds sets for each channel are given,following the detection results presented by means of Monte Carlo simulation strategy based on simulated target model and three measured targets.In particular,the theoretical analysis and simulation results highlight that the MC-OS detector can efficiently detect range-spread targets in white Gaussian noise. 展开更多
关键词 order statistics strong scattering cell multi-channel range-spread target
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A time-sharing multi-channel pulse amplitude analyzer 被引量:2
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作者 Lian-Jun Jiang Xiang Zhou +1 位作者 Tong-Yu Wu Ze-Jie Yin 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第4期91-96,共6页
A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pu... A conventional multi-channel pulse amplitude analyzer acquires single energy spectrum,but provides no information on its tendency with time.To address the limitation,we propose a scheme of time-sharing multichannel pulse amplitude analyzer(TSMCA).A dual-port random access memory is divided into two storage spaces,one for current energy spectrum data acquisition and another for previous energy spectrum data storage.The two tasks can be performed simultaneously,and the time-related variation tendency of energy spectrum can be obtained.A prototype system of TSMCA is designed.It performs nicely,with maximum channel number of 4096 in capacity of 2^(32)/Ch,minimal time-sharing slice of 25 ms,the differential nonlinearity of <1.5%,and the integral nonlinearity of <0.3%. 展开更多
关键词 multi-channel pulse AMPLITUDE ANALYZER MCA Time-sharing ADC DUAL-PORT RAM
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Receding Horizon Estimation for Linear Discrete-time Systems with Multi-channel Observation Delays 被引量:2
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作者 Chunyan Han Chaochao Li +1 位作者 Fang He Yue Liu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第2期478-484,共7页
This paper investigates the receding horizon state estimation for the linear discrete-time system with multi-channel observation delays. The receding horizon estimation is designed by the reorganized observation techn... This paper investigates the receding horizon state estimation for the linear discrete-time system with multi-channel observation delays. The receding horizon estimation is designed by the reorganized observation technique and the linear unbiased estimation method. The estimation gains are developed by solving a set of Riccati equations, and a stability result about the state estimation is shown. Finally, an example is given to illustrate the efficiency of the receding horizon state estimation. 展开更多
关键词 multi-channel OBSERVATION DELAYS receding HORIZON ESTIMATION reorganized OBSERVATION STABILITY analysis
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Multi-Channel Iterative FDE for Single Carrier Block Transmission over Underwater Acoustic Channels 被引量:3
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作者 HE Chengbing HUO Siyu +2 位作者 ZHANG Qunfei WANG Han HUANG Jianguo 《China Communications》 SCIE CSCD 2015年第8期55-61,共7页
Recently, single carrier block transmission(SCBT) has received much attention in high-rate phase-coherent underwater acoustic communication.However,minimum-mean-square-error(MMSE) linear FDE may suffer performance los... Recently, single carrier block transmission(SCBT) has received much attention in high-rate phase-coherent underwater acoustic communication.However,minimum-mean-square-error(MMSE) linear FDE may suffer performance loss in the severely time dispersive underwater acoustic channel. To combat the channel distortion, a novel multi-channel receiver with maximum ratio combining and a low complex T/4 fractional iterative frequency domain equalization(FDE) is investigated to improve diversity gain and the bit error rate(BER) performance. The proposed method has been verified by the real data from a lake underwater acoustic communication test in November 2011. At 1.8 km, the useful data rates are around 1500 and 3000 bits/s for BPSK and QPSK respectively. The results show the improvements of system performance. Compared with MMSE FDE system, the output SNR improvement is 6.9 d B, and the BER is from 10-3 to no error bits for BPSK. The output SNR improvement is 5.3 d B, and the BER is from 1.91×10-2 to 2.2×10-4for QPSK. 展开更多
关键词 underwater acoustic communi-cation single carrier multi-channel frequency domain equalization iterative processing
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A Hybrid Deep Learning Scheme for Multi-Channel Sleep Stage Classification 被引量:3
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作者 Wei Pei Yan Li +1 位作者 Siuly Siuly Peng Wen 《Computers, Materials & Continua》 SCIE EI 2022年第4期889-905,共17页
Sleep stage classification plays a significant role in the accurate diagnosis and treatment of sleep-related diseases.This study aims to develop an efficient deep learning based scheme for correctly identifying sleep ... Sleep stage classification plays a significant role in the accurate diagnosis and treatment of sleep-related diseases.This study aims to develop an efficient deep learning based scheme for correctly identifying sleep stages using multi-biological signals such as electroencephalography(EEG),electrocardiogram(ECG),electromyogram(EMG),and electrooculogram(EOG).Most of the prior studies in sleep stage classification focus on hand-crafted feature extraction methods.Traditional hand-crafted feature extraction methods choose features manually from raw data,which is tedious,and these features are limited in their ability to balance efficiency and accuracy.Moreover,most of the existing works on sleep staging are either single channel(a single-lead EEG may not contain enough information)or only EEG signal based which can not reveal more complicated physical features for reliable classification of various sleep stages.This study proposes an approach to combine Convolutional Neural Networks(CNNs)and Gated Recurrent Units(GRUs)that can discover hidden features from multi-biological signal data to recognize the different sleep stages efficiently.In the proposed scheme,the CNN is designed to extract concealed features from the multi-biological signals,and the GRU is employed to automatically learn the transition rules among different sleep stages.After that,the softmax layers are used to classify various sleep stages.The proposed method was tested on two publicly available databases:Sleep Heart Health Study(SHHS)and St.Vincent’s University Hospital/University College Dublin Sleep Apnoea(UCDDB).The experimental results reveal that the proposed model yields better performance compared to state-of-the-art works.Our proposed scheme will assist in building a new system to deal with multi-channel or multi-modal signal processing tasks in various applications. 展开更多
关键词 Convolutional neural networks gated recurrent unit sleep stages multi-channel 1 Introduction
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A Multi-Gap Multi-Channel Gas Switch for the Linear Transformer Driver 被引量:3
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作者 刘轩东 梁天学 +4 位作者 孙凤举 姜晓峰 李佳 孙福 邱爱慈 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第6期725-729,共5页
A multi-gap and multi-channel gas switch with convexo-convex discal planet electrodes was designed and investigated. Eight gaps are formed in series by a trigger electrode, six intermediate electrodes and two high vol... A multi-gap and multi-channel gas switch with convexo-convex discal planet electrodes was designed and investigated. Eight gaps are formed in series by a trigger electrode, six intermediate electrodes and two high voltage electrodes with a uniform gap length of 5 ram. The self breakdown and triggered breakdown performance of the switch are reported. Both the delay time and jitter decrease with the increase in the trigger voltage, switching coefficient and the decrease in the trigger isolating resistor. The delay time of the switch is about 40 ns, and the jitter is less than 2 ns when charged with 4-85 kV and triggered by a voltage pule of -75 kV. The inductance of the switch is about 30 nH. 展开更多
关键词 multi-gap multi-channel gas spark closing switch linear transformer driver delay time JITTER
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Automatic pickup of arrival time of channel wave based on multi-channel constraints 被引量:2
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作者 Wang Bao-Li 《Applied Geophysics》 SCIE CSCD 2018年第1期118-124,150,共8页
Accurately detecting the arrival time of a channel wave in a coal seam is very important for in-seam seismic data processing. The arrival time greatly affects the accuracy of the channel wave inversion and the compute... Accurately detecting the arrival time of a channel wave in a coal seam is very important for in-seam seismic data processing. The arrival time greatly affects the accuracy of the channel wave inversion and the computed tomography (CT) result. However, because the signal-to-noise ratio of in-seam seismic data is reduced by the long wavelength and strong frequency dispersion, accurately timing the arrival of channel waves is extremely difficult. For this purpose, we propose a method that automatically picks up the arrival time of channel waves based on multi-channel constraints. We first estimate the Jaccard similarity coefficient of two ray paths, then apply it as a weight coefficient for stacking the multi- channel dispersion spectra. The reasonableness and effectiveness of the proposed method is verified in an actual data application. Most importantly, the method increases the degree of automation and the pickup precision of the channel-wave arrival time. 展开更多
关键词 seismic channel wave DISPERSION multi-channel constraint Jaccard similarity coefficient arrival time picking
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Joint channel assignment and cross-layer routing protocol for multi-radio multi-channel Ad Hoc networks 被引量:2
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作者 Yang Lu Junming Guan +1 位作者 Zhen Wei Qilin Wu 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第6期1095-1102,共8页
To study multi-radio multi-channel (MR-MC) Ad Hoc networks based on 802.11, an efficient cross-layer routing protocol with the function of joint channel assignment, called joint channel assignment and cross-layer ro... To study multi-radio multi-channel (MR-MC) Ad Hoc networks based on 802.11, an efficient cross-layer routing protocol with the function of joint channel assignment, called joint channel assignment and cross-layer routing (JCACR), is presented. Firstly, this paper introduces a new concept called channel utilization percentage (CUP), which is for measuring the contention level of different channels in a node’s neighborhood, and deduces its optimal value for determining whether a channel is overloaded or not. Then, a metric parameter named channel selection metric (CSM) is designed, which actually reffects not only the channel status but also corresponding node’s capacity to seize it. JCACR evaluates channel assignment by CSM, performs a local optimization by assigning each node a channel with the smaller CSM value, and changes the working channel dynamically when the channel is overloaded. Therefore, the network load balancing can be achieved. In addition, simulation shows that, when compared with the protocol of weighted cumulative expected transfer time (WCETT), the new protocol can improve the network throughput and reduce the end-to-end average delay with fewer overheads. 展开更多
关键词 Ad Hoc network multi-radio multi-channel channel assignment routing protocol channel utilization percentage.
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Design and Implementation of a High-Speed Multi-Channel Data Acquisition System 被引量:1
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作者 黄默 龙腾 《Journal of Beijing Institute of Technology》 EI CAS 2006年第3期323-326,共4页
A data acquisition system (DAS) to implement high-speed, real-time and multi-channel data acquisition and store is presented. The control of the system is implemented by the combination of complex programable logic ... A data acquisition system (DAS) to implement high-speed, real-time and multi-channel data acquisition and store is presented. The control of the system is implemented by the combination of complex programable logic device (CPLD) and digital signal processing (DSP), the bulk buffer of the system is implemented by the combination of CPLD, DSP, and synchronous dynamic random access memory (SDRAM), and the data transfer is implemented by the combination of DSP, first in first out (FIFO), universal serial bus (USB) and USB hub. The system could not only work independently in single-channel mode, but also implement high-speed real-time multi-channel data acquisition system (MCDAS) by the combination of multiple single-channels. The sampling rate and data storage capacity of each channel could reach up to 100 million sampiing per second and 256 MB respectively. 展开更多
关键词 multi-channel data acquisition system (MCDAS) bulk buffer multi-channel
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