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Group scheduling with general position-dependent effect
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作者 虞先玉 张玉林 张玉环 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期354-359,共6页
In order to investigate more realistic group scheduling problems with position-dependent effects,the model of general position-dependent group scheduling is proposed,where the actual group setup times and actual proce... In order to investigate more realistic group scheduling problems with position-dependent effects,the model of general position-dependent group scheduling is proposed,where the actual group setup times and actual processing times are described by general functions of the normal group setup time and position in the sequence.These general functions are not assumed to have specific function structures,and are not restricted to be monotone.By mathematical analysis and proof,each considered problem is decomposed into a group scheduling process and a job scheduling process,and each scheduling process is transferred into the classic assignment problem or the classic single-machine sequence problem,and then the computational complexity to solve the considered problem is analyzed.Analysis results show that,even with general position-dependent job processing times,both the single machine makespan minimization group scheduling problems and the parallel-machine total load minimization group scheduling problems remain polynomially solvable. 展开更多
关键词 group scheduling position-dependent MAKESPAN total load
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Non-hypergeometric Type of Polynomials and Solutions of Schrodinger Equation with Position-Dependent Mass 被引量:1
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作者 鞠国兴 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第8期235-240,共6页
Using the coordinate transformation method, we study the polynomial solutions of the Schr6dinger equation with position-dependent mass (PDM). The explicit expressions for the potentials, energy eigenvalues, and eige... Using the coordinate transformation method, we study the polynomial solutions of the Schr6dinger equation with position-dependent mass (PDM). The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The issues related to normalization of the wavefunetions and Hermiticity of the Hamiltonian are also analyzed. 展开更多
关键词 SchrSdinger equation position-dependent mass EIGENFUNCTION EIGENVALUE coordinate transfor-mation method polynomials solution
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Generation of Exactly Solvable Potentials of Position-Dependent Mass Schrödinger Equation from Hulthen Potential 被引量:1
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作者 Hangshadhar Rajbongshi Ngangkham Nimai Singh 《Journal of Modern Physics》 2013年第11期1540-1545,共6页
Exactly Solvable Potentials (ESPs) of Position-Dependent Mass (PDM) Schrodinger equation are generated from Hulthen Potential (parent system) by using Extended Transformation (ET) method. The method includes a Co-ordi... Exactly Solvable Potentials (ESPs) of Position-Dependent Mass (PDM) Schrodinger equation are generated from Hulthen Potential (parent system) by using Extended Transformation (ET) method. The method includes a Co-ordinate Transformation (CT) followed by Functional Transformation (FT) of wave function. Mass function of parent system gets transformed to that of generated system. Two new ESPs are generated. The explicit expressions of mass functions, energy eigenvalues and corresponding wave functions for newly generated potentials (systems) are derived. System specific regrouping method is also discussed. 展开更多
关键词 position-dependent Mass Hulthen POTENTIAL Co-Ordinate TRANSFORMATION Extended TRANSFORMATION EXACT ANALYTIC Solution
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Coordinate Transformation and Exact Solutions of Schrodinger Equation with Position-Dependent Effective Mass
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作者 JU Guo-Xing CAI Chang-Ying +1 位作者 XIANG Yang REN Zhong-Zhou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1001-1009,共9页
Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the sy... Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The eigenfunctions can be expressed in terms of the Jacobi, Hermite, and generalized Laguerre polynomials. All potentials for these solvable systems have an extra term Vm, which is produced from the dependence of mass on the position, compared with those for the systems of constant mass. The properties of Vm for several mass functions are discussed. 展开更多
关键词 coordinate transformation Schrodinger equation position-dependent mass EIGENFUNCTION special functions
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On superintegrable systems with a position-dependent mass in polar-like coordinates
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作者 Hai Zhang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期96-100,共5页
For a superintegrable system defined in plane polar-like coordinates introduced by Szumiński et al. and studied by Fordy, we show that the system with a position-dependent mass is separable in three distinct coordina... For a superintegrable system defined in plane polar-like coordinates introduced by Szumiński et al. and studied by Fordy, we show that the system with a position-dependent mass is separable in three distinct coordinate systems. The corresponding separation equations and additional integrals of motion are derived explicitly. The closure algebra of integrals is deduced. We also make a generalization of this system by employing the classical Jacobi method. Lastly a sufficient condition which ensures flatness of the underlying space is derived via explicit calculation. 展开更多
关键词 superintegrable system separation of variables position-dependent mass polar-likecoordinates Jacobi method
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Bound states of the Dirac equation with position-dependent mass for the Eckart potential
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作者 Bahar M. K. Yasuk F. 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第1期62-67,共6页
Studying with the asymptotic iteration method, we present approximate solutions of the Dirac equation for the Eckart potential in the case of position-dependent mass. The centrifugal term is approximated by an exponen... Studying with the asymptotic iteration method, we present approximate solutions of the Dirac equation for the Eckart potential in the case of position-dependent mass. The centrifugal term is approximated by an exponential form, and the relativistic energy spectrum and the normalized eigenfunctions are obtained explicitly. 展开更多
关键词 Dirac equation position-dependent mass Eckart potential asymptotic iteration method
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Shannon information entropies for position-dependent mass Schrdinger problem with a hyperbolic well
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作者 Sun Guo-Hua Duan Popov +1 位作者 Oscar Camacho-Nieto Dong Shi-Hai 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期45-52,共8页
The Shannon information entropy for the Schrodinger equation with a nonuniform solitonic mass is evaluated for a hyperbolic-type potential. The number of nodes of the wave functions in the transformed space z are brok... The Shannon information entropy for the Schrodinger equation with a nonuniform solitonic mass is evaluated for a hyperbolic-type potential. The number of nodes of the wave functions in the transformed space z are broken when recovered to original space x. The position Sx and momentum S p information entropies for six low-lying states are calculated. We notice that the Sx decreases with the increasing mass barrier width a and becomes negative beyond a particular width a,while the Sp first increases with a and then decreases with it. The negative Sx exists for the probability densities that are highly localized. We find that the probability density ρ(x) for n = 1, 3, 5 are greater than 1 at position x = 0. Some interesting features of the information entropy densities ρs(x) and ρs(p) are demonstrated. The Bialynicki-Birula-Mycielski(BBM)inequality is also tested for these states and found to hold. 展开更多
关键词 position-dependent mass Shannon information entropy hyperbolic potential Fourier transform
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Generalized Harmonic Oscillator and the Schrdinger Equation with Position-Dependent Mass
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作者 JU Guo-Xing CAI Chang-Ying REN Zhong-Zhou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期797-802,共6页
We study the generalized harmonic oscillator that has both the position-dependent mass and the potential depending on the form of mass function in a more general framework. The explicit expressions of the eigenvalue a... We study the generalized harmonic oscillator that has both the position-dependent mass and the potential depending on the form of mass function in a more general framework. The explicit expressions of the eigenvalue and eigenfunction for such a system are given, they have the same forms as those for the usual harmonic oscillator with constant mass. The coherent state and its properties corresponding effective potentials for several mass functions, for the system with PDM are also discussed. We give the the systems with such potentials are isospectral to the usual harmonic oscillator. 展开更多
关键词 generalized harmonic oscillator Schr6dinger equation position-dependent mass coherent state
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Localization of s-Wave and Quantum Effective Potential of a Quasi-free Particle with Position-Dependent Mass
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作者 JU Guo-Xing XIANG Yang REN Zhong-Zhou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期819-825,共7页
The properties of the 8-wave for a quasl-free partide with position-dependent mass (PDM) have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the fr... The properties of the 8-wave for a quasl-free partide with position-dependent mass (PDM) have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the free quantum particle around the origin only occurs in two dimensions, the quasi-free particle with PDM can experience attractive forces in D dimensions except D = 1 when its mass function satisfies some conditions. The effective mass of a particle varying with its position can induce effective interaction, which may be attractive in some cases. The analytical expressions of the eigenfunctions and the corresponding probability densities for the 8-waves of the two- and three-dimensional systems with a special PDM are given, and the existences of localization around the origin for these systems are shown. 展开更多
关键词 position-dependent mass S-WAVE Schrodinger equation dimensionality of the space LOCALIZATION EIGENFUNCTION probability density
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Semiclassical Method to Schroedinger Equation with Position-Dependent Effective Mass
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作者 CHEN Gang XUAN Pei-Cai CHEN Zi-Dong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第1X期39-42,共4页
In this paper, two novel semiclassical methods including the standard and supersymmetric WKB quantization conditions are suggested to discuss the Schroedinger equation with position-dependent effective mass. From a pr... In this paper, two novel semiclassical methods including the standard and supersymmetric WKB quantization conditions are suggested to discuss the Schroedinger equation with position-dependent effective mass. From a proper coordinate transformation, the formalism of the Schroedinger equation with position-dependent effective mass is mapped into isospectral one with constant mass and therefore for a given mass distribution and physical potential function the bound state energy spectrum can be determined easily by above method associated with a simple integral formula. It is shown that our method can give the analytical results for some exactly-solvable quantum systems. 展开更多
关键词 Schroedinger equation position-dependent effective mass standard WKB quantization supersymmetric WKB quantization
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Approximate energies and thermal properties of a position-dependent mass charged particle under external magnetic fields
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作者 M Eshghi H Mehraban S M Ikhdair 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第6期22-30,共9页
We solve the Schrodinger equation with a position-dependent mass(PDM) charged particle interacted via the superposition of the Morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharo... We solve the Schrodinger equation with a position-dependent mass(PDM) charged particle interacted via the superposition of the Morse-plus-Coulomb potentials and is under the influence of external magnetic and Aharonov–Bohm(AB) flux fields. The nonrelativistic bound state energies together with their wave functions are calculated for two spatially-dependent mass distribution functions. We also study the thermal quantities of such a system. Further, the canonical formalism is used to compute various thermodynamic variables for second choosing mass by using the Gibbs formalism. We give plots for energy states as a function of various physical parameters. The behavior of the internal energy, specific heat, and entropy as functions of temperature and mass density parameter in the inverse-square mass case for different values of magnetic field are shown. 展开更多
关键词 Schr?dinger equation Morse-plus-Coulomb potentials position-dependent mass distribution functions perpendicular magnetic and Aharonov–Bohm flux fields
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Energy states of the Hulthen plus Coulomb-like potential with position-dependent mass function in external magnetic fields
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作者 M Eshghi R Sever S M Ikhdair 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期234-238,共5页
We need to solve a suitable exponential form of the position-dependent mass (PDM) Schr6dinger equation with a charged particle placed in the Hulthen plus Coulomb-like potential field and under the actions of the ext... We need to solve a suitable exponential form of the position-dependent mass (PDM) Schr6dinger equation with a charged particle placed in the Hulthen plus Coulomb-like potential field and under the actions of the external magnetic and Aharonov-Bohm (AB) flux fields. The bound state energies and their corresponding wave functions are calculated for the spatially-dependent mass distribution function of interest in physics. A few plots of some numerical results with respect to the energy are shown. 展开更多
关键词 Schr6dinger equation Hulthen plus Coulomb-like potential position-dependent mass distributionfunctions perpendicular magnetic and Aharonov-Bohm flux fields
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Performance Prediction Based Workload Scheduling in Co-Located Cluster
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作者 Dongyang Ou Yongjian Ren Congfeng Jiang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第5期2043-2067,共25页
Cloud service providers generally co-locate online services and batch jobs onto the same computer cluster,where the resources can be pooled in order to maximize data center resource utilization.Due to resource competi... Cloud service providers generally co-locate online services and batch jobs onto the same computer cluster,where the resources can be pooled in order to maximize data center resource utilization.Due to resource competition between batch jobs and online services,co-location frequently impairs the performance of online services.This study presents a quality of service(QoS)prediction-based schedulingmodel(QPSM)for co-locatedworkloads.The performance prediction of QPSM consists of two parts:the prediction of an online service’s QoS anomaly based on XGBoost and the prediction of the completion time of an offline batch job based on randomforest.On-line service QoS anomaly prediction is used to evaluate the influence of batch jobmix on on-line service performance,and batch job completion time prediction is utilized to reduce the total waiting time of batch jobs.When the same number of batch jobs are scheduled in experiments using typical test sets such as CloudSuite,the scheduling time required by QPSM is reduced by about 6 h on average compared with the first-come,first-served strategy and by about 11 h compared with the random scheduling strategy.Compared with the non-co-located situation,QPSM can improve CPU resource utilization by 12.15% and memory resource utilization by 5.7% on average.Experiments show that the QPSM scheduling strategy proposed in this study can effectively guarantee the quality of online services and further improve cluster resource utilization. 展开更多
关键词 Co-located cluster workload scheduling online service batch jobs data center
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The Relation between Mental Workload and Face Temperature in Flight Simulation
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作者 Amin Bonyad Hamdi Ben Abdessalem Claude Frasson 《Journal of Behavioral and Brain Science》 2024年第2期64-92,共29页
In this research, we study the relationship between mental workload and facial temperature of aircraft participants during a simulated takeoff flight. We conducted experiments to comprehend the correlation between wor... In this research, we study the relationship between mental workload and facial temperature of aircraft participants during a simulated takeoff flight. We conducted experiments to comprehend the correlation between work and facial temperature within the flight simulator. The experiment involved a group of 10 participants who played the role of pilots in a simulated A-320 flight. Six different flying scenarios were designed to simulate normal and emergency situations on airplane takeoff that would occur in different levels of mental workload for the participants. The measurements were workload assessment, face temperatures, and heart rate monitoring. Throughout the experiments, we collected a total of 120 instances of takeoffs, together with over 10 hours of time-series data including heart rate, workload, and face thermal images and temperatures. Comparative analysis of EEG data and thermal image types, revealed intriguing findings. The results indicate a notable inverse relationship between workload and facial muscle temperatures, as well as facial landmark points. The results of this study contribute to a deeper understanding of the physiological effects of workload, as well as practical implications for aviation safety and performance. 展开更多
关键词 Mental workload EEG Thermal Images Flight Simulation AVIATION Face Temperature
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Energy-Aware Scheduling Scheme Using Workload-Aware Consolidation Technique in Cloud Data Centres 被引量:2
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作者 黎红友 王江勇 +2 位作者 彭舰 王俊峰 刘唐 《China Communications》 SCIE CSCD 2013年第12期114-124,共11页
To reduce energy consumption in cloud data centres,in this paper,we propose two algorithms called the Energy-aware Scheduling algorithm using Workload-aware Consolidation Technique(ESWCT) and the Energyaware Live Migr... To reduce energy consumption in cloud data centres,in this paper,we propose two algorithms called the Energy-aware Scheduling algorithm using Workload-aware Consolidation Technique(ESWCT) and the Energyaware Live Migration algorithm using Workload-aware Consolidation Technique(ELMWCT).As opposed to traditional energy-aware scheduling algorithms,which often focus on only one-dimensional resource,the two algorithms are based on the fact that multiple resources(such as CPU,memory and network bandwidth)are shared by users concurrently in cloud data centres and heterogeneous workloads have different resource consumption characteristics.Both algorithms investigate the problem of consolidating heterogeneous workloads.They try to execute all Virtual Machines(VMs) with the minimum amount of Physical Machines(PMs),and then power off unused physical servers to reduce power consumption.Simulation results show that both algorithms efficiently utilise the resources in cloud data centres,and the multidimensional resources have good balanced utilizations,which demonstrate their promising energy saving capability. 展开更多
关键词 energy-aware scheduling hetero-geneous workloads workload-aware consoli-dation cloud data centres
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Integrated Evaluation of Air Traffic Controller Workload Based on Matter-Element Analysis 被引量:1
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作者 张明 韩松臣 《Journal of Southwest Jiaotong University(English Edition)》 2008年第2期164-169,共6页
A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a mansystem engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which i... A model for evaluating the controller workload was presented based on matter-element analysis, particularly from a mansystem engineering perspective. On the basis of a questionnaire survey, 18 kinds of indexes which influence the controller workload were determined. By establishing the classical field and node field of the controller workload, the correlation function of the controller workload grade was obtained; then the correlation degree and estimated grade of controller workload were given. A case study verifies the feasibility of the proposed evaluation method. 展开更多
关键词 Air traffic control Controller workload Matter-element analysis EXTENICS CORRELATION
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Multicenter application of a nursing workload measurement scale in adult hospitalization units 被引量:1
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作者 María Fuensanta Hellín Gil Marzena Mikla +3 位作者 Ana Myriam Seva Llor María Dolores Roldán Valcárcel Francisco Javier Ibáñez-López María JoséLópez Montesinos 《International Journal of Nursing Sciences》 CSCD 2022年第4期460-466,I0002,共8页
Objectives:The study aimed to the multicenter application of a nursing workload measurement scale in the internal medicine and surgery adults hospitalization units.Methods:The study design was a multicenter,observatio... Objectives:The study aimed to the multicenter application of a nursing workload measurement scale in the internal medicine and surgery adults hospitalization units.Methods:The study design was a multicenter,observational,and descriptive study.A multicenter application of the MIDENF®nursing workload measurement scale was carried out,which consists of 21 items,and covers the four nursing functions(patient care items,teaching,manager,and researcher),in units of hospitalization of adults of internal medicine and surgery of four different hospitals.Each item contains one or more of the nursing interventions of Nursing Interventions Classification(NIC)and has an assigned time,after comparing the real time it takes to perform each intervention with the North American Nursing Diagnosis Association(NANDA)standardized time.The study was carried out during nine months of the year 2020,measuring two days each month in the three work shifts(morning,evening,and night)to all patients admitted on the days of measurement in the indicated units.Results:The descriptive and inferential analysis of 11,756 completed scales,5,695 in general surgery and 6,061 in internal medicine,showed a greater care load for the two units during the morning shift(227,034 min in general surgery,261,835 min in internal medicine),especially in the items of“self-care”,“medication”,“common invasive procedures”,“fluid therapy”,and“patient and family support”,while the managerial function was similar during the three work shifts in the two units studied,getting values between 57,348 and 62,901min.In the analysis by shift and unit,statistical significance was obtained both for the total workload and the four nursing functions(P<0.001).Conclusions:It is shown that the use of validated scales with the standardized language of nursing functions,adapted to the units,provides objective information to adjust the nursing staff to the real situation of care in any hospital and unit where it is applied,improving quality and patient safety. 展开更多
关键词 HOSPITAL Measurement Nursing administration research workload
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Synthetic Workload Generation for Cloud Computing Applications 被引量:1
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作者 Arshdeep Bahga Vijay Krishna Madisetti 《Journal of Software Engineering and Applications》 2011年第7期396-410,共15页
We present techniques for characterization, modeling and generation of workloads for cloud computing applications. Methods for capturing the workloads of cloud computing applications in two different models - benchmar... We present techniques for characterization, modeling and generation of workloads for cloud computing applications. Methods for capturing the workloads of cloud computing applications in two different models - benchmark application and workload models are described. We give the design and implementation of a synthetic workload generator that accepts the benchmark and workload model specifications generated by the characterization and modeling of workloads of cloud computing applications. We propose the Georgia Tech Cloud Workload Specification Language (GT-CWSL) that provides a structured way for specification of application workloads. The GT-CWSL combines the specifications of benchmark and workload models to create workload specifications that are used by a synthetic workload generator to generate synthetic workloads for performance evaluation of cloud computing applications. 展开更多
关键词 SYNTHETIC workload BENCHMARKING Analytical Modeling CLOUD Computing workload Specification LANGUAGE
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Assessment of Effects of Concomitant Exposure to Sound, Heat, and Physical Workload Changes on Physiological Parameters in Five Different Combination Modes, a Controlled Laboratory Study 被引量:1
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作者 Hossein Molaeifar Farahnaz Khajehnasiri +1 位作者 Kiana Nikeghbal Zahra Zamanian 《Sound & Vibration》 EI 2020年第3期139-148,共10页
Exposure to sound,heat,and increased physical workload can change physiological parameters.This study was conducted to evaluate the effect of concomitant exposure to sound,heat,and physical workload changes on physiol... Exposure to sound,heat,and increased physical workload can change physiological parameters.This study was conducted to evaluate the effect of concomitant exposure to sound,heat,and physical workload changes on physiological parameters in controlled laboratory conditions.This experimental crosssectional study was conducted in 35 male university students with a mean age of 25.75 years and a mean BMI of 22.69 kg/m2.Systolic and diastolic blood pressure and heart rate were measured after 15 min rest in the laboratory,5 and 10 min after starting the experiment,and then after 20 min in controlled laboratory conditions in five combination modes.The combination modes were(Sound:65 dB,WBGT:22°C,Speed:1.7,Slope:10%),(Sound:65 dB,WBGT:22°C,Speed:3.4,Slope:14%),(Sound:95 dB,WBGT:22°C,Speed:1.7,Slope:10%),(Sound:65 dB,WBGT:32°C,Speed:1.7,Slope:10%),and(Sound:95 dB,WBGT:32°C,Speed:3.4,Slope:14%).Mixed model analysis and paired t-test were applied for analysis.The results showed that the mean physiological parameters(Systolic and diastolic blood pressure and heart rate)increased when different combination modes worsened(Sound from 65 to 95 dB,WBGT from 22°C to 32°C,speed from 1.7 to 3.4,and slope from 10%to 14%,and when sound:95 dB,WBGT:32°C,Speed:3.4,and Slope:14%).Moreover,the mean changes of systolic and diastolic blood pressure were significant in all conditions when compared with the reference condition(Sound:65 dB,WBGT:22°C,Speed:1.7,and Slope:10%).The mean heart rate changes were also significant except for exposure to the second condition(Sound:65 dB,WBGT:22°C,Speed:3.4,Slope:14%)and the third condition(Sound:95 dB,WBGT:22°C,Speed:1.7,Slope:10%).Exposure to hazardous levels of sound,heat,and workload has adverse effects on physiological parameters.Concomitant exposure to all three hazards has a synergistic effect and increases the adverse effect. 展开更多
关键词 Concomitant exposure SOUND HEAT physical workload physiological parameters
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Analysis of workload of tank crew under the conditions of informatization 被引量:5
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作者 Ming MAO Fang XIE +1 位作者 Jian-jun HU Bo SU 《Defence Technology(防务技术)》 SCIE EI CAS 2014年第1期17-21,共5页
A consensus has been reached that the tanks need to be integrated into the informatization battlefield. With the development of technology,the tank crew has being gradually decreased, so the research on two-soldier cr... A consensus has been reached that the tanks need to be integrated into the informatization battlefield. With the development of technology,the tank crew has being gradually decreased, so the research on two-soldier crew tank has become a hotspot. The workload of tank crew under the conditions of informatization is analyzed based on the combat mission of tank and the typical combat scenarios, and the impact of new technologies on workload is evaluated. The crew members in tank can be reduced from three to two, but it is necessary to substantially improve the automation of target search and the reliability of each subsystem and component. 展开更多
关键词 信息化战场 工作量 坦克 乘员 作战任务 工作负载 目标搜索 自动化
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