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The response time Analysis of Digital Broadcasting System

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Wuhan University Journal of Natural Sciences 2005年第3期10卷 515-519页

作者： WANGShuo ZHANGJiang-ling FENGDan SchoolofComputerScienceandTechnology HuazhongUniversityofScienceandTechnologyWuhan430074HubeiChina

Digital broadcasting system has become a high-light of research on computer application. To respond to the changes of the playbill in the broadcasting system in real time, the response time of the system must be studied. There is scarcely the research on this area currently. The influence factors in the response time are analyzed; the model on the response time of the system service is built; how the influence factors affect the response time of the system service is validated; and four improvement measures are proposed to minimize the response time of system service.

关键词： Key words digital broadcasting system response time analysis real time

Strong-field response time and its implications on attosecond measurement

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Chinese Physics B 2022年第3期31卷 16-23页

作者： Chao Chen Jiayin Che Xuejiao Xie Shang Wang Guoguo Xin Yanjun Chen College of Physics and Information Technology Shaan'xi Normal UniversityXi'an 710119China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China School of Physics Northwest UniversityXi'an 710127China

To measure and control the electron motion in atoms and molecules by the strong laser field on the attosecond time scale is one of the research frontiers of atomic and molecular photophysics. It involves many new phenomena and processes and raises a series of questions of concepts, theories, and methods. Recent studies show that the Coulomb potential can cause the ionization time lag(about 100 attoseconds) between instants of the field maximum and the ionization-rate maximum. This lag can be understood as the response time of the electronic wave function to the strong-field-induced ionization event. It has a profound influence on the subsequent ultrafast dynamics of the ionized electron and can significantly change the time–frequency properties of electron trajectory(an important theoretical tool for attosecond measurement). Here, the research progress of response time and its implications on attosecond measurement are briefly introduced.

关键词： response time strong-field ionization Coulomb effect attosecond measurement

Fork-Join program response time on multiprocessors with exchangeable join

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第6期7卷 927-936页

作者： WANG Yong-cai ZHAO Qian-chuan ZHENG Da-zhong Center for Intelligent and Networked Systems Department of Automation Tsinghua University Beijing 100084 China

The Fork-Join program consisting of K parallel tasks is a useful model for a large number of computing applications. When the parallel processor has multi-channels, later tasks may finish execution earlier than their earlier tasks and may join with tasks from other programs. This phenomenon is called exchangeable join (EJ), which introduces correlation to the task’s service time. In this work, we investigate the response time of multiprocessor systems with EJ with a new approach. We analyze two aspects of this kind of systems: exchangeable join (EJ) and the capacity constraint (CC). We prove that the system response time can be effectively reduced by EJ, while the reduced amount is constrained by the capacity of the multiprocessor. An upper bound model is constructed based on this analysis and a quick estimation algorithm is proposed. The approximation formula is verified by extensive simulation results, which show that the relative error of approximation is less than 5%.

关键词： Exchangeable join First come first served (FCFS) Fork-Join Multiprocessor response time

Finite Difference Solution of response time Delay of Magneto-rhelological Damper

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Chinese Journal of Mechanical Engineering 2009年第3期22卷 446-450页

作者： ZOU Mingsong HOU Baolin School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China

Magneto-rhelological（MR） dampers are devices that employ rheological fluids to modify their mechanical properties. Their mechanical simplicity, high dynamic range, lower power requirements, large force capacity, robustness and safe maimer of operation in cases of failure have made them attractive devices for semi-active real-time control in civil, aerospace and automotive applications. time response characteristic is one of the most important technical performances of MR dampers, and response time directly affects the control frequency, application range and the actual effect of MR dampers. In this study, one kind of finite difference solution for predicting the response time ofmagneto-rheological dampers from ＂off-state＂ to ＂on-state＂ is put forward. A laminar flow model is used to describe the flow in the MR valve, and a bi-viscous fluid flow model is utilized to describe the relationship of shear stress and shear rate of MR fluid. An explicit difference format is used to diseretize the Novior-Stoks equation, and stability condition of this algorithm is built by Von-Neumann stability criterion. The pressure gradient along the flow duct is solved by a dichotomy algorithm with iteration, and the changing curve of the damping force versus time of MR damper is obtained as well. According to the abovementioned numerical algorithm, the damping forces versus time curves from ＂off-state＂ to ＂on-state＂ of a cylindrical piston type MR damper are computed. Moreover, the MR damper is installed in a material test system（MTS）, the magnetic field in the wire circles of the MR damper is ＂triggered＂ when the MR damper is imposed to do a constant speed motion, and the damping force curves are recorded. The comparison between numerical results and experimental results indicates that this finite difference algorithm can be used to estimate the response time delay of MR dampers.

关键词： magneto-rheological damper response time finite difference method

An Improved Text-Based and Image-Based CAPTCHA Based on Solving and response time

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Computers, Materials & Continua 2023年第2期74卷 2661-2675页

作者： Ademola Olusola Adesina Patrick Seun Ayobioloja Ibidun Christiana Obagbuwa Tola John Odule Adenrele AAfolorunso Sunday Adeola Ajagbe Department of Mathematical Sciences Olabisi Onabanjo University Ago-Iwoye120107Nigeria National Open University of Nigeria Abuja900001Nigeria Sol Plaatje University KimberleyNorthern Cape8305South Africa Computer Engineering Department Ladoke Akintola University of TechnologyLAUTECHOgbomoso210214Nigeria

CAPTCHA is an acronym that stands for Completely Automated Public Turing Test to tell Computers and Humans Apart(CAPTCHA),it is a good example of an authentication system that can be used to determine the true identity of any *** serves as a security measure to prevent an attack caused by web bots(automatic programs)during an online *** can come as text-based or image-based depending on the project and the *** usability and robustness,as well as level of security,provided each of the varies and call for the development of an improved ***,this paper studied and improved two different CAPTCHA systems(the text-based CAPTCHA and image-based CAPTCHA).The textbased and image-based CAPTCHAwere designed using *** time and solving time are the two metrics used to determine the effectiveness and efficiency of the two CAPTCHA *** inclusion of response time and solving time improved the shortfall of the usability and robustness of the existing *** developed system was tested using 200 students from the Federal College of Animal Health and Production *** results of each of the participants,for the two CAPTCHAs,were extracted from the database and subjected to analysis using *** result shows that textbased CAPTCHAhas the lowest average solving time(21.3333 s)with a 47.8%success rate while image-based CAPTCHA has the highest average solving time was 23.5138 s with a 52.8%success *** average response time for the image-based CAPTCHA was 2.1855 s with a 37.9%success rate lower than the text-based CAPTCHA response time(3.5561 s)with a 62.1%success *** indicates that the text-based CAPTCHA is more effective in terms of usability tests while image-based CAPTCHA is more efficient in terms of system responsiveness and recommended for potential users.

关键词： CAPTCHA computational intelligence information security response time solving time

What are the Acute Effects of Aerobic Exercise on Fractionated response time:A Systematic Review and Meta-analysis

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Journal of Science in Sport and Exercise 2020年第2期2卷 97-112页

作者： Razie J Alibazi Dawson Kidgell Maryam Zoghi Shapour Jaberzadeh Non-invasive Brain Stimulation and Neuroplasticity Laboratory Department of PhysiotherapySchool of Primary and Allied Health CareFaculty of MedicineNursing and Health ScienceMonash UniversityP.O.Box 527MelbourneVIC 3199Australia Department of Rehabilitation Nutrition and SportSchool of Allied HealthLa Trobe UniversityBundooraVICAustralia

Recently,there have been several studies that have examined the acute effects of aerobic exercise on cognitive ***,one precise indicator of cognitive function is response time(RT),which has two main components;premotor time(PMT)and motor time(MT).PMT is the time for perception,decision making and response preparation,while MT is executing the *** fractionated response time(FRT)instead of RT provides a more precise estimate of the location of the effect of aerobic exercise on cognitive or motor components of the *** is emerging evidence that shows an acute bout of exercise may improve ***,the purpose of this systematic review and meta-analysis was to explore the acute effect of aerobic exercise on FRT by considering the effects of various cognitive function *** studies were included investigating FRT during and/or after aerobic *** results indicated that during exercise,PMT increased in simple reaction time and decreased in flanker task;MT decreased in choice reaction time;interestingly,RT decreased when it was assessed by choice reaction time and flanker task,almost similar to PMT and *** exercise,PMT decreased specifically in flanker and go/no-go ***,MT and RT did not change *** conclusion,as changes in RT are affected by both PMT and MT,FRT provides a more precise estimate of the locus of the effects of aerobic exercise on response time.

关键词： Physical activity Cognitive function response time Premotor time

The simulation of temperature dependence of responsivity and response time for 6H-SiC UV photodetector

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Chinese Physics B 2007年第5期16卷 1276-1279页

作者：张义门周拥华张玉明 Key Lab of Ministry of Education for Wide Band-Gap Semiconductor Materials and Devices Microelectronics Institute Xidian University Xi'an 710071 China

In this paper the temperature dependence of responsivity and response time for 6H-SiC ultraviolet （UV） photodetector is simulated based on numerical model in the range from 300 K to 900 K. The simulation results show that the responsivity and the response time of device are less sensitive to temperature and this kind of UV photodetector has excellent temperature stability. Also the effects of device structure and bias voltage on the responsivity and the response time are presented. The thicker the drift region is, the higher the responsivity and the longer the response time are. So the thickness of drift region has to be carefully designed to make trade-off between responsivity and response time.

关键词： 6H-Silicon carbide UV photodetector absorption coefficient responsivity response time

Analysis of response time probability distribution of workflows

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Journal of Southeast University(English Edition) 2006年第1期22卷 137-142页

作者：卢光松葛运建合肥工业大学管理学院合肥230009 中国科学院合肥智能机械研究所合肥230031

An evaluation approach for the response time probability distribution of workflows based on the fluid stochastic Petri net formalism is presented. Firstly, some problems about stochastic workflow net modeling are discussed. Then how to convert a stochastic workflow net model into a fluid stochastic Petri net model is described. The response time distribution can be obtained directly upon the transient state solution of the fluid stochastic Petri net model. In the proposed approach, there are not any restrictions on the structure of workflow models, and the processing times of workflow tasks can be modeled by using arbitrary probability distributions. Large workflow models can be efficiently tackled by recursively using a net reduction technique.

关键词： workflow response time stochastic workflow net fluid stochastic Petri net

Improving surveys with paradata:analytic uses of response time A study based on process information of China Family Dynamic Survey

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China Population and Development Studies 2018年第2期2卷 204-223页

作者： Yi Shi Jun Feng Xiaoqin Luo China Population and Development Research Center BeijingChina National Academy of Economic Strategy Chinese Academy of Social SciencesBeijingChina

This study uses paradata and survey data from the China Family Dynamic Survey to analyze the issue of response time in a questionnaire *** survey questions were classified into three levels and we compared the inter-group differences of response time between four kinds of questions which included information inquiries,logical calculations,intimate information and logical *** used OLS method to perform a regression analysis to identify the impediments to response time and discussed the roles played by the survey locale,and the characteristics of interviewees and those of *** major impediments that prolonged response time were factors that impeded comprehension of the *** impediments included the difficulties interviewees had understanding questions,questions that did not take into account the different cultural backgrounds of interviewees,the complexity of questionnaires,and the performance of ***,this paper puts forward some suggestions for questionnaire design and investigation processes to reduce impediments to comprehension and improve the ability of interviewers.

关键词： Survey quality response time Paradata Questionnaire design