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Understanding the Impact of AI-Mediated Communication on Trust Formation and Negotiation Outcomes in Professional Remote Collaboration
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作者 Natalie Nkembuh 《Journal of Computer and Communications》 2025年第2期172-190,共19页
This study investigates the effects of AI-mediated communication (AMC) on trust-building and negotiation outcomes in professional remote collaboration settings. Through a mixed-methods approach combining experimental ... This study investigates the effects of AI-mediated communication (AMC) on trust-building and negotiation outcomes in professional remote collaboration settings. Through a mixed-methods approach combining experimental design and qualitative analysis (N = 120), we examine how AI intermediaries influence communication dynamics, relationship building, and decision-making processes. Results indicate that while AMC initially creates barriers to trust formation, it ultimately leads to enhanced communication outcomes and stronger professional relationships when implemented with appropriate transparency and support. The study revealed a 31% improvement in cross-cultural understanding and a 24% increase in negotiation satisfaction rates when using AI-mediated channels with proper transparency measures. These findings contribute to the theoretical understanding of technology-mediated communication and practical applications for organizations implementing AI communication tools. 展开更多
关键词 AI-Mediated Communication Trust Formation Professional Collaboration Negotiation Outcomes Remote Work
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New Delay Doppler Communication Paradigm in 6G Era:A Survey of Orthogonal Time Frequency Space(OTFS) 被引量:12
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作者 Weijie Yuan Shuangyang Li +4 位作者 Zhiqiang Wei Yuanhao Cui Jiamo Jiang Haijun Zhang Pingzhi Fan 《China Communications》 SCIE CSCD 2023年第6期1-25,共25页
In the 6G era,Space-Air-Ground Integrated Network(SAGIN)are anticipated to deliver global coverage,necessitating support for a diverse array of emerging applications in high-mobility,hostile environments.Under such co... In the 6G era,Space-Air-Ground Integrated Network(SAGIN)are anticipated to deliver global coverage,necessitating support for a diverse array of emerging applications in high-mobility,hostile environments.Under such conditions,conventional orthogonal frequency division multiplexing(OFDM)modulation,widely employed in cellular and Wi-Fi communication systems,experiences performance degradation due to significant Doppler shifts.To overcome this obstacle,a novel twodimensional(2D)modulation approach,namely orthogonal time frequency space(OTFS),has emerged as a key enabler for future high-mobility use cases.Distinctively,OTFS modulates information within the delay-Doppler(DD)domain,as opposed to the timefrequency(TF)domain utilized by OFDM.This offers advantages such as Doppler and delay resilience,reduced signaling latency,a lower peak-to-average ratio(PAPR),and a reduced-complexity implementation.Recent studies further indicate that the direct interplay between information and the physical world in the DD domain positions OTFS as a promising waveform for achieving integrated sensing and communications(ISAC).In this article,we present an in-depth review of OTFS technology in the context of the 6G era,encompassing fundamentals,recent advancements,and future directions.Our objective is to provide a helpful resource for researchers engaged in the field of OTFS. 展开更多
关键词 OTFS 6G delay-Doppler(DD)domain
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Optimizing Optical Attocells Positioning of Indoor Visible Light Communication System 被引量:1
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作者 Mohammed S.M.Gismalla Asrul I.Azmi +5 位作者 Mohd R.Salim Farabi Iqbal Mohammad F.L.Abdullah Mosab Hamdan Muzaffar Hamzah Abu Sahmah M.Supa’at 《Computers, Materials & Continua》 SCIE EI 2023年第2期3607-3625,共19页
Visible light communication(VLC),which is a prominent emerging solution that complements the radio frequency(RF)technology,exhibits the potential to meet the demands of fifth-generation(5G)and beyond technologies.The ... Visible light communication(VLC),which is a prominent emerging solution that complements the radio frequency(RF)technology,exhibits the potential to meet the demands of fifth-generation(5G)and beyond technologies.The random movement of mobile terminals in the indoor environment is a challenge in the VLC system.The model of optical attocells has a critical role in the uniform distribution and the quality of communication links in terms of received power and signal-to-noise ratio(SNR).As such,the optical attocells positions were optimized in this study with a developed try and error(TE)algorithm.The optimized optical attocells were examined and compared with previous models.This novel approach had successfully increased minimum received power from−1.29 to−0.225 dBm,along with enhanced SNR performance by 2.06 dB.The bit error rate(BER)was reduced to 4.42×10−8 and 6.63×10−14 by utilizing OOK-NRZ and BPSK modulation techniques,respectively.The optimized attocells positions displayed better uniform distribution,as both received power and SNR performances improved by 0.45 and 0.026,respectively.As the results of the proposed model are optimal,it is suitable for standard office and room model applications. 展开更多
关键词 Visible light communication(VLC) optical attocell received power signal-to-noise ratio(SNR) bit error rate(BER) coefficient of variation(CV)
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Beyond Algorithms: A Comprehensive Analysis of AI-Driven Personalization in Strategic Communications 被引量:1
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作者 Natalie Nkembuh 《Journal of Computer and Communications》 2024年第10期112-131,共20页
This comprehensive study investigates the multifaceted impact of AI-powered personalization on strategic communications, delving deeply into its opportunities, challenges, and future directions. Employing a rigorous m... This comprehensive study investigates the multifaceted impact of AI-powered personalization on strategic communications, delving deeply into its opportunities, challenges, and future directions. Employing a rigorous mixed-methods approach, we conduct an in-depth analysis of the effects of AI-driven personalization on audience engagement, brand perception, and conversion rates across various industries and communication channels. Our findings reveal that while AI-powered personalization significantly enhances communication effectiveness and offers unprecedented opportunities for audience connection, it also raises critical ethical considerations and implementation challenges. The study contributes substantially to the growing body of literature on AI in communications, offering both theoretical insights and practical guidelines for professionals navigating this rapidly evolving landscape. Furthermore, we propose a novel framework for ethical AI implementation in strategic communications and outline a robust agenda for future research in this dynamic field. 展开更多
关键词 Artificial Intelligence (AI) Strategic Communications PERSONALIZATION Machine Learning Natural Language Processing (NLP) Customer Engagement Data Analytics Digital Marketing Audience Segmentation Communication Effectiveness AI Ethics Conversion Optimization Predictive Analytics Content Personalization Marketing Automation
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Modeling Components and Services of LTE Mobile Communications System
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作者 Ishtiaq Ahmed Choudhry Nazir Ahmad Zafar 《International Journal of Communications, Network and System Sciences》 2012年第12期815-824,共10页
The latest wireless broadband network standard is LTE (Long Term Evolution) which is developed by 3GPP (3rd Generation Partnership Project). It will enable mobile devices such as smart phones, tablets and laptops to a... The latest wireless broadband network standard is LTE (Long Term Evolution) which is developed by 3GPP (3rd Generation Partnership Project). It will enable mobile devices such as smart phones, tablets and laptops to access Internet at a very high speed along with lots of multimedia services. There are many issues that are yet to be solved due to dynamic complex nature of wireless systems, multimedia software applications and software requirements. Poor service quality, service disconnections due to mobility, seamless handover, handover interruption time and downward compatibility to other Radio Access Networks (RAN) are some of the key issues for the current LTE systems that are addressed very recently in the scientific literature. Formal method is one of the promising software engineering techniques that assure quality and perfection in software system models. Formal methods use mathematical language to explicitly specify system specifications and requirements that serve as initial grounds for further development and implementation. It efficiently handles all component connections and resource management parameters using discrete structures. Z Schema language is used to model static aspects of LTE communications system. All the schemas are being verified using Z/Eves toolset. The aim is to provide sound mathematical foundation for system validation and verification that eventually results in a more reliable, scalable and complete software system. 展开更多
关键词 LTE COMMUNICATIONS System FORMAL Methods EMERGING Software MATHEMATICAL LANGUAGE Z Notation
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Observed communication between oncologists and patients:A causal model of communication competence
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作者 Katie LaPlant Turkiewicz Mike Allen +1 位作者 Maria K Venetis Jeffrey D Robinson 《World Journal of Meta-Analysis》 2014年第4期186-193,共8页
AIM: To investigate and test a causal model derivedfrom previous meta-analytic data of health provider be-haviors and patient satisfaction.METHODS: A literature search was conducted forrelevant manuscripts that met ... AIM: To investigate and test a causal model derivedfrom previous meta-analytic data of health provider be-haviors and patient satisfaction.METHODS: A literature search was conducted forrelevant manuscripts that met the following criteria:Reported an analysis of provider-patient interaction inthe context of an oncology interview; the study hadto measure at least two of the variables of interest tothe model (provider activity, provider patient-centeredcommunication, provider facilitative communication,patient activity, patient involvement, and patient satis-faction or reduced anxiety); and the information had tobe reported in a manner that permitted the calculationof a zero-order correlation between at least two of thevariables under consideration. Data were transformedinto correlation coefficients and compiled to producethe correlation matrix used for data analysis. The test of the causal model is a comparison of the expected correlation matrix generated using an Ordinary Least Squares method of estimation. The expected matrix iscompared to the actual matrix of zero order correlation coeffcients. A model is considered a possible ft if the level of deviation is less than expected due to random sampling error as measured by a chi-square statistic. The signifcance of the path coeffcients was tested us-ing a z test. Lastly, the Sobel test provides a test of the level of mediation provided by a variable and provides an estimate of the level of mediation for each connec-tion. Such a test is warranted in models with multiple paths.RESULTS: A test of the original model indicated a lack of ft with the summary data. The largest discrepancy in the model was between the patient satisfaction and the provider patient-centered utterances. The observed correlation was far larger than expected given a medi-ated relationship. The test of a modifed model was un-dertaken to determine possible ft. The corrected model provides a fit to within tolerance as evaluated by the test statistic, χ2 (8, average n = 342) = 10.22. Each of the path coefficients for the model reveals that each one can be considered signifcant, P 〈 0.05. The Sobel test examining the impact of the mediating variables demonstrated that patient involvement is a signifcantmediator in the model, Sobel statistic = 3.56, P 〈 0.05. Patient active was also demonstrated to be a signifcant mediator in the model, Sobel statistic = 4.21, P 〈 0.05. The statistics indicate that patient behavior mediates the relationship between provider behavior and patient satisfaction with the interaction.CONCLUSION: The results demonstrate empirical support for the importance of patient-centered care and satisfy the need for empirical casual support of provider-patient behaviors on health outcomes. 展开更多
关键词 Provider-patient communication Communication competence ONCOLOGIST Cancer Causal model META-ANALYSIS
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Modelling and Performance Analysis of Visible Light Communication System in Industrial Implementations
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作者 Mohammed S.M.Gismalla Asrul I.Azmi +5 位作者 Mohd R.Salim Farabi Iqbal Mohammad F.L.Abdullah Mosab Hamdan Muzaffar Hamzah Abu Sahmah M.Supa’at 《Computers, Materials & Continua》 SCIE EI 2023年第11期2189-2204,共16页
Visible light communication(VLC)has a paramount role in industrial implementations,especially for better energy efficiency,high speed-data rates,and low susceptibility to interference.However,since studies on VLC for ... Visible light communication(VLC)has a paramount role in industrial implementations,especially for better energy efficiency,high speed-data rates,and low susceptibility to interference.However,since studies on VLC for industrial implementations are in scarcity,areas concerning illumination optimisation and communication performances demand further investigation.As such,this paper presents a new modelling of light fixture distribution for a warehouse model to provide acceptable illumination and communication performances.The proposed model was evaluated based on various semi-angles at half power(SAAHP)and different height levels for several parameters,including received power,signal to noise ratio(SNR),and bit error rate(BER).The results revealed improvement in terms of received power and SNR with 30 Mbps data rate.Various modulations were studied to improve the link quality,whereby better average BER values of 5.55×10^(−15) and 1.06×10^(−10) had been achieved with 4 PAM and 8 PPM,respectively.The simulation outcomes are indeed viable for the practical warehouse model. 展开更多
关键词 Visible light communication(VLC) industrial applications warehouse model light fixtures bit error rate(BER)
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Embedded System Implementation of Airborne Communication Terminals
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作者 Lei Wang Zhizhong Ding +2 位作者 Rui Huang Qian Li Hesheng Cheng 《Wireless Engineering and Technology》 2013年第3期139-144,共6页
Airborne communication terminal is a key unit in Ad hoc network of aircrafts. This paper mainly focuses on its implementation by embedded system, which is based on Samsung S3C2410 chip. System architecture, Linux tail... Airborne communication terminal is a key unit in Ad hoc network of aircrafts. This paper mainly focuses on its implementation by embedded system, which is based on Samsung S3C2410 chip. System architecture, Linux tailoring and touch-screen driver design are discussed in detail. Considering the requirements of stability and efficiency of the operating system, dynamic driver-loading method was employed firstly and only the necessary library files were transplanted to assist and test. The drivers finally were directly put into kernel configuration and then an integrated kernel was transplanted. Regarding to the problem of positioning issues on touch-screen, which is implemented in this system, an accurate positioning method is also presented. 展开更多
关键词 AIRBORNE Communication TERMINAL Ad HOC Network Embedded System Touch-Screen
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Performance Analysis of SWIPT-Enabled Two-Way Relay Based on Generalized Carrier Index Differential Chaos Shift Keying
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作者 Cheng Guixian Xu Liangwen +1 位作者 Zhang Mengxuan Xu Weikai 《China Communications》 2025年第6期131-139,共9页
This paper investigates the performance of a simultaneous wireless information and power transfer(SWIPT)enabled two-way one-relay(TWOR)system based on generalized carrier index differential chaos shift keying(GCI-DCSK... This paper investigates the performance of a simultaneous wireless information and power transfer(SWIPT)enabled two-way one-relay(TWOR)system based on generalized carrier index differential chaos shift keying(GCI-DCSK).We derive the expressions for the proposed scheme’s bit error rate(BER),considering both additive white Gaussian noise(AWGN)and multipath Rayleigh fading channels.The simulation results demonstrate that the proposed SWIPT-enabled GCI-DCSK TWOR system performs slightly worse than the DCSK TWOR system without SWIPT at the same distance.However,a notable advantage of the proposed system is that the relay node is self-sustainable,which is particularly significant considering the challenges associated with battery replacement in relay nodes.Furthermore,we derive the outage probability and validate the accuracy of the derived formulas using simulation results. 展开更多
关键词 DCSK energy efficiency index modulation self-sustainable SWIPT
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Deep learning aided underwater acoustic OFDM receivers: Model-driven or data-driven?
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作者 Hao Zhao Miaowen Wen +3 位作者 Fei Ji Yaokun Liang Hua Yu Cui Yang 《Digital Communications and Networks》 2025年第3期866-877,共12页
The Underwater Acoustic(UWA)channel is bandwidth-constrained and experiences doubly selective fading.It is challenging to acquire perfect channel knowledge for Orthogonal Frequency Division Multiplexing(OFDM)communica... The Underwater Acoustic(UWA)channel is bandwidth-constrained and experiences doubly selective fading.It is challenging to acquire perfect channel knowledge for Orthogonal Frequency Division Multiplexing(OFDM)communications using a finite number of pilots.On the other hand,Deep Learning(DL)approaches have been very successful in wireless OFDM communications.However,whether they will work underwater is still a mystery.For the first time,this paper compares two categories of DL-based UWA OFDM receivers:the DataDriven(DD)method,which performs as an end-to-end black box,and the Model-Driven(MD)method,also known as the model-based data-driven method,which combines DL and expert OFDM receiver knowledge.The encoder-decoder framework and Convolutional Neural Network(CNN)structure are employed to establish the DD receiver.On the other hand,an unfolding-based Minimum Mean Square Error(MMSE)structure is adopted for the MD receiver.We analyze the characteristics of different receivers by Monte Carlo simulations under diverse communications conditions and propose a strategy for selecting a proper receiver under different communication scenarios.Field trials in the pool and sea are also conducted to verify the feasibility and advantages of the DL receivers.It is observed that DL receivers perform better than conventional receivers in terms of bit error rate. 展开更多
关键词 Deep learning Doubly-selective channels DATA-DRIVEN Model-driven Underwater acoustic communication OFDM
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Does the Social Media Platform Change the Impression of Teaching Assistants?: A Facebook vs. Twitter Study
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作者 Zuoming Wang 《Social Networking》 2025年第1期1-13,共13页
This study analyzed how impressions are formed online depending on the type of social media and the implications that may come from the over-disclosure of information. Using a Qualtrics survey, 97 participants viewed ... This study analyzed how impressions are formed online depending on the type of social media and the implications that may come from the over-disclosure of information. Using a Qualtrics survey, 97 participants viewed the profile of a female teaching assistant on Twitter and Facebook. While there was little difference between the two social media, the use of self-disclosure on Twitter seemed slightly more inappropriate for sharing personal information. 展开更多
关键词 Impression Online Social Media Teaching Assistant
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Sub-Diffraction Limit Quantum Metrology for Nanofabrication
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作者 Wenyi Ye Yang Li +10 位作者 Lianwei Chen Mingbo Pu Zheting Meng Yuanjian Huang Hengshuo Guo Xiaoyin Li Yinghui Guo Xiong Li Yun Long Emmanuel Stratakis Xiangang Luo 《Engineering》 2025年第6期96-103,共8页
Optical monitoring of object position and alignment with nanoscale precision is critical for ultra-precision measurement applications,such as micro/nano-fabrication,weak force sensing,and micro-scopic imaging.Traditio... Optical monitoring of object position and alignment with nanoscale precision is critical for ultra-precision measurement applications,such as micro/nano-fabrication,weak force sensing,and micro-scopic imaging.Traditional optical nanometry methods often rely on precision nanostructure fabrication,multi-beam interferometry,or complex post-processing algorithms,which can limit their practical use.In this study,we introduced a simplified and robust quantum measurement technique with an achievable resolution of 2.2 pm and an experimental demonstration of 1 nm resolution,distinguishing it from conventional interferometry,which depended on multiple reference beams.We designed a metasurface substrate with a mode-conversion function,in which an incident Gaussian beam is converted into higher-order transverse electromagnetic mode(TEM)modes.A theoretical analysis,including calculations of the Fisher information,demonstrated that the accuracy was maintained for nanoscale displacements.In conclusion,the study findings provide a new approach for precise alignment and metrology of nanofabrication and other advanced applications. 展开更多
关键词 Nanofabrication Precision measurement Diffraction limit Quantum metrology
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COVID-19 Vaccine Distribution Patterns for Prioritized Age Group: Analysis of European Nations
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作者 Ogbonnaya Ezichi Victor Okpanachi +7 位作者 Joy Jibunoh Wuraola Awosan Prosper Tchoumo Anthony Akande Chibuzor Amaechi Jubril Sanusi Funmilayo Ogunsanwo Rofiat Adesina 《Open Journal of Epidemiology》 2025年第1期1-18,共18页
The emergence of the SARS-CoV-2 virus resulted in a health and economic crisis worldwide. Although everyone is susceptible to COVID-19, the elderly have compromised immune systems and often suffer from chronic underly... The emergence of the SARS-CoV-2 virus resulted in a health and economic crisis worldwide. Although everyone is susceptible to COVID-19, the elderly have compromised immune systems and often suffer from chronic underlying diseases, which makes them more vulnerable. This study aims to assess variation in COVID-19 vaccine distribution patterns across different age groups in European countries and to understand the extent to which European countries have prioritized vulnerable age groups (age > 70) in their vaccination programs. The study utilized open data from the European Center for Disease Prevention and Control (ECDC) and employed an observational, retrospective study design to examine the distribution of the COVID-19 vaccine among various age groups in several European countries from September 2021 to September 2023. Results reveal that vaccination rates increase with age, peaking at the 25 - 49 age group (1.34 × 10−4), after which there was a decline in vaccination rate. Analysis of variance (ANOVA) was used to investigate the equality of vaccination rates across the 29 countries in Europe, which resulted in a p-value of 70) during the study period as no country achieved the 70% coverage aimed by WHO. Continuous efforts must be made to ensure larger coverage of COVID-19 vaccination among this vulnerable population in order to protect them from severe outcomes in this region. 展开更多
关键词 SARS-CoV-2 COVID-19 Vaccines Prioritized Age Group European Nations
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A High-Speed Bi-Directional Visible Light Communication System Based on RGB-LED 被引量:4
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作者 WANG Yuanouan CHI Nan 《China Communications》 SCIE CSCD 2014年第3期40-44,共5页
In this paper, we propose and experimentally demonstrate a bi-directional indoor communication system based on visible light RGB-LED. Spectrally efficient modulation formats (QAM-OFDM), advanced digital signal proce... In this paper, we propose and experimentally demonstrate a bi-directional indoor communication system based on visible light RGB-LED. Spectrally efficient modulation formats (QAM-OFDM), advanced digital signal processing, pre- and post- equalization are adopted to compensate the severe frequency response of indoor channel. In this system, we utilize red-green-blue Light emitting diodes (LEDs), of which each color can be used to carry different signals. For downlink, the low frequencies of each color are used while for uplink, the high frequencies are used. The overall data rate of downlink and uplink are 1.15-Gb/s and 300-Mb/s. The bit error ratios (BERs) for all channels after 0.7 m indoor delivery are below pre-forward- error-correction (pre-FEC) threshold of 3.8×10-3. To the best of our knowledge, this is the highest data rate in bi-directional visible light communication system. 展开更多
关键词 visible light communication bi-directional transmission orthogonal frequencydivision multiplexing light emitting diode
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Frequency bands of negative refraction in finite one-dimensional photonic crystals 被引量:4
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作者 陈园园 黄肇明 +2 位作者 施解龙 李春芳 王奇 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期173-178,共6页
We have discussed theoretically the negative refraction in finite one-dimensional (1D) photonic crystals (PCs) composed of alternative layers with high index contrast. The frequency bands of negative refraction ar... We have discussed theoretically the negative refraction in finite one-dimensional (1D) photonic crystals (PCs) composed of alternative layers with high index contrast. The frequency bands of negative refraction are obtained with the help of the photonic band structure, the group velocity and the power transmittance, which are all obtained in analytical expression. There shows negative transverse position shift at the endface when negative refraction occurs, which is analysed in detail. 展开更多
关键词 photonic crystal negative refraction group velocity
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Mission-Oriented Configuration Model of Aircraft Carrying Spares and Dynamic Optimization Policy 被引量:3
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作者 Ruan Minzhi Wang Rui Kong Qingfu 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2016年第5期626-632,共7页
Spare parts are critical to scheduled maintenance and fault repair, and can directly affect the readiness and combat capability of equipment. Equipmentrs capacity of carrying spares is influenced by its storage space ... Spare parts are critical to scheduled maintenance and fault repair, and can directly affect the readiness and combat capability of equipment. Equipmentrs capacity of carrying spares is influenced by its storage space and scales, so it is necessary to consider economic factors, e.g. spares cost, as well as non-economic ones, such as spares volume, mass and scale, when optimizing spares configuration. Aiming at this problem, the optimization model based on multi-constraints for carrying spares is built by METRIC theory and system analysis. Through the introduction of Lagrange factors, the spares cost is transformed to shadow price, and the optimization method for carrying spares and the dynamic adjustment policy of Lagrange factors are proposed. The result of a given example is analyzed, and demonstrates that the proposed model can be optimized with all constraints, and the research can provide a new way for carrying spares optimization. 展开更多
关键词 carrying spares projectl multi-constrains optimization Lagrange factors operational availability
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Dynamic analysis, simulation, and control of a 6-DOF IRB-120 robot manipulator using sliding mode control and boundary layer method 被引量:3
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作者 Mojtaba HADI BARHAGHTALAB Vahid MEIGOLI +2 位作者 Mohammad Reza GOLBAHAR HAGHIGHI Seyyed Ahmad NAYERI Arash EBRAHIMI 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第9期2219-2244,共26页
Because of its ease of implementation,a linear PID controller is generally used to control robotic manipulators.Linear controllers cannot effectively cope with uncertainties and variations in the parameters;therefore,... Because of its ease of implementation,a linear PID controller is generally used to control robotic manipulators.Linear controllers cannot effectively cope with uncertainties and variations in the parameters;therefore,nonlinear controllers with robust performance which can cope with these are recommended.The sliding mode control(SMC)is a robust state feedback control method for nonlinear systems that,in addition having a simple design,efficiently overcomes uncertainties and disturbances in the system.It also has a very fast transient response that is desirable when controlling robotic manipulators.The most critical drawback to SMC is chattering in the control input signal.To solve this problem,in this study,SMC is used with a boundary layer(SMCBL)to eliminate the chattering and improve the performance of the system.The proposed SMCBL was compared with inverse dynamic control(IDC),a conventional nonlinear control method.The kinematic and dynamic equations of the IRB-120 robot manipulator were initially extracted completely and accurately,and then the control of the robot manipulator using SMC was evaluated.For validation,the proposed control method was implemented on a 6-DOF IRB-120 robot manipulator in the presence of uncertainties.The results were simulated,tested,and compared in the MATLAB/Simulink environment.To further validate our work,the results were tested and confirmed experimentally on an actual IRB-120 robot manipulator. 展开更多
关键词 robot manipulator control IRB-120 robot sliding mode control sliding mode control with boundary layer inverse dynamic control
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Impacts of Packet Collisions on Link Throughput in CSMA Wireless Networks 被引量:3
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作者 Caihong Kai Shengli Zhang Lusheng Wang 《China Communications》 SCIE CSCD 2018年第3期1-14,共14页
It is known that packet collisions in wireless networks will deteriorate system performance, hence substantial efforts have been made to avoid collision in multi-user access designs. Also, there have been many studies... It is known that packet collisions in wireless networks will deteriorate system performance, hence substantial efforts have been made to avoid collision in multi-user access designs. Also, there have been many studies on throughput analysis of CSMA wireless networks. However, for a typical CSMA network in which not all nodes can sense each other, it is still not well investigated how link throughputs are affected by collisions. We note that in practical 802.11-like networks, the time is divided into mini-timeslots and packet collisions are in fact unavoidable. Thus, it is desirable to move forward to explore how collisions in such a network will affect system performance. Based on the collision-free ideal CSMA network(ICN) model, this paper attempts to analyze link throughputs when taking the backoff collisions into account and examine the effect of collisions on link throughputs. Specifically, we propose an Extended Ideal CSMA Network(EICN) model to characterize the collision effects as well as the interactions and dependency among links in the network. Based on EICN, we could directly compute link throughputs and collision probabilities. Simulations show that the EICN model is of high accuracy. Under various network topologies and protocol parameter settings, the computation error of link throughputs using EICN is kept to 4% or below. Interestingly, we find that unlike expected, the effect of collisions on link throughputs in a modest CSMA wireless network is not significant, which enriches our understanding on practical CSMA wireless networks such as Wi-Fi. 展开更多
关键词 CSMA protocol wireless net-works COLLISIONS throughput analysis
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Prediction of chaotic systems with multidimensional recurrent least squares support vector machines 被引量:2
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作者 孙建成 周亚同 罗建国 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第6期1208-1215,共8页
In this paper, we propose a multidimensional version of recurrent least squares support vector machines (MDRLS- SVM) to solve the problem about the prediction of chaotic system. To acquire better prediction performa... In this paper, we propose a multidimensional version of recurrent least squares support vector machines (MDRLS- SVM) to solve the problem about the prediction of chaotic system. To acquire better prediction performance, the high-dimensional space, which provides more information on the system than the scalar time series, is first reconstructed utilizing Takens's embedding theorem. Then the MDRLS-SVM instead of traditional RLS-SVM is used in the high- dimensional space, and the prediction performance can be improved from the point of view of reconstructed embedding phase space. In addition, the MDRLS-SVM algorithm is analysed in the context of noise, and we also find that the MDRLS-SVM has lower sensitivity to noise than the RLS-SVM. 展开更多
关键词 chaotic systems support vector machines least squares noise
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