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时型及社会时差对轮班护士体质量指数的影响
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作者 朱泓旭 许毅 +2 位作者 陈婧 李霜 阎妍 《军事护理》 CSCD 北大核心 2024年第10期31-35,共5页
目的 探讨时型和社会时差对轮班护士体质量指数(body mass index, BMI)的影响,为护理管理者制订轮班护理人员BMI管理方案提供理论依据。方法 2023年7-8月,采用便利抽样法选取西南地区5所纬度相近的三级甲等综合性医院的429名轮班护士为... 目的 探讨时型和社会时差对轮班护士体质量指数(body mass index, BMI)的影响,为护理管理者制订轮班护理人员BMI管理方案提供理论依据。方法 2023年7-8月,采用便利抽样法选取西南地区5所纬度相近的三级甲等综合性医院的429名轮班护士为研究对象。以轮班人员慕尼黑时型测定工具、晨晚型量表及BMI测定等对其调查。结果 不同年龄、性别、婚姻状况、时型和社会时差等的轮班护士,其BMI水平差异均有统计学意义(均P<0.05)。控制混杂因素后,时型和社会时差对轮班护士BMI影响的主效应及交互作用显著(F时型=51.16,P时型<0.01;F社会时差=68.02,P社会时差<0.01;F交互=51.48,P交互<0.01)。不同时型下,社会时差对轮班护士BMI水平的差异均有统计学意义(P<0.01)。高社会时差时,时型对轮班护士BMI水平的差异有统计学意义(P<0.01)。结论 时型和社会时差共同影响轮班护士BMI水平,建议考虑以两者交互关系为理论依据,针对轮班护士BMI水平管理采取干预,进而改善轮班护士代谢紊乱。 展开更多
关键词 轮班 时型 社会时差 体质量指数
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睡眠质量、运动量、时型与大学生健康的关系研究 被引量:2
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作者 谌宏玥 毛芳香 +1 位作者 韩静 崔乃雪 《中国健康教育》 北大核心 2023年第8期697-703,共7页
目的 探讨大学生的睡眠质量在其时型与健康间的中介作用,以及运动量在3条路径中的调节作用,为制定改善大学生健康的干预措施提供理论依据。方法 采用简版清晨-夜晚型评定量表(rMEQ)、匹兹堡睡眠质量指数量表(PSQI)、健康调查简表(SF-36... 目的 探讨大学生的睡眠质量在其时型与健康间的中介作用,以及运动量在3条路径中的调节作用,为制定改善大学生健康的干预措施提供理论依据。方法 采用简版清晨-夜晚型评定量表(rMEQ)、匹兹堡睡眠质量指数量表(PSQI)、健康调查简表(SF-36)、体育活动等级量表(PARS-3)对827名在校大学生进行问卷调查。采用单因素方差分析、Bonferroni法、Pearson相关和逐步回归模型对数据进行分析。结果 不同时型的大学生在睡眠质量、躯体健康和心理健康维度上的差异,以及不同运动量的大学生在睡眠质量和躯体健康维度上的差异均有统计学意义(P<0.05);睡眠质量与躯体、心理健康呈负相关(r=-0.48~-0.47,P<0.01)。睡眠质量在时型与健康间起完全中介作用;运动量在时型→躯体健康、睡眠质量→心理健康路径中存在调节作用。在运动量大的大学生中,夜晚型大学生的躯体健康优于中间型(t=2.01,P=0.044);且睡眠质量越差的大学生,其心理健康得分越低(b=-1.41,t=-2.26,P=0.024)。结论 大学生的睡眠质量在其时型与健康间起完全中介作用。大学生的运动量在其时型与躯体健康、睡眠质量与心理健康间起调节作用。 展开更多
关键词 睡眠质量 运动 时型 健康 路径分析
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大学生心理健康、自我调节对时型的影响 被引量:1
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作者 甄鋒泉 吴坤 +3 位作者 张耀心 夏侯雨欢 邱琦 罗俊熙 《心理学进展》 2016年第6期700-712,共13页
目的:探讨大学生时型和心理健康、自我调节之间的关系。方法:选取某大学314名在校学生为被试,共收回298份有效问卷。采用清晨型/夜晚型问卷(MEQ)调查被试的时型,一般健康问卷(GHQ-12)测量被试的心理健康水平,自我控制量表中文版(SCS)和... 目的:探讨大学生时型和心理健康、自我调节之间的关系。方法:选取某大学314名在校学生为被试,共收回298份有效问卷。采用清晨型/夜晚型问卷(MEQ)调查被试的时型,一般健康问卷(GHQ-12)测量被试的心理健康水平,自我控制量表中文版(SCS)和拖延量表(PS)测量被试的自我调节能力。结果:MEQ问卷平均得分(49.41 &#177;8.07),GHQ-12问卷平均得分(25.73 &#177;5.00),SCS量表平均得分(55.97 &#177;8.74),PS量表平均得分(42.12 &#177;6.49)。各个量表分数之间均有显著相关(r = ?0.6~0.78, p <0.01),年级与MEQ总分呈显著负相关(p <0.01)。回归分析显示,PS总分、SCS总分和年级对MEQ总分的预测作用显著(R2 = 0.24),SCS的分量表健康习惯和节制娱乐、以及年级能显著预测MEQ总分(R2 = 0.34)。中介效应检验显示,自我调节系数在心理健康与时型之间起完全中介作用。结论:年级和自我调节能力可以预测时型,心理健康可以通过自我调节能力影响时型。 展开更多
关键词 心理健康 自我调节 时型 中介效应
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Oscillations of the Solutions of Hyperbolic Partial Differential Equations of Neutral Type 被引量:4
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作者 刘安平 曹少琛 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期7-13,共7页
In this paper, oscillatory properties of solutions of certain nonlinear hyperbolic partial differential equations are investigated and a series of sufficient conditions for oscillations of the equations are establishe... In this paper, oscillatory properties of solutions of certain nonlinear hyperbolic partial differential equations are investigated and a series of sufficient conditions for oscillations of the equations are established. The results fully indicate that the oscillations are caused by delay. 展开更多
关键词 HYPERBOLIC DELAY OSCILLATION nonlinear NEUTRAL
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Dynamical analysis for a malware propagation model in wireless sensor network 被引量:4
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作者 宋礼鹏 张蓉萍 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第2期136-144,共9页
The threat of malware in wireless sensor network has stimulated some activities to model and analyze the malware prevalence.To understand the dynamics of malware propagation in wireless sensor network,we propose a nov... The threat of malware in wireless sensor network has stimulated some activities to model and analyze the malware prevalence.To understand the dynamics of malware propagation in wireless sensor network,we propose a novel epidemic model named as e-SEIR(susceptible-exposed-infectious-recovered)model,which is a set of delayed differential equations,in this paper.The model has taken into account the following two factors:1 Multi-state antivirus measures;2 Temporary immune period.Then,the stability and Hopf bifurcation at the equilibria of linearized model are carefully analyzed by considering the distribution of eigenvalues of characteristic equations.Both mathematical analysis and numerical simulations show that the dynamical features of the proposed model rely on the basic reproduction number R0 and time delayτ.This novel model can help us to better understand and predict the propagation behaviors of malware in wireless sensor networks. 展开更多
关键词 wireless sensor network STABILITY Hopf bifurcation epidemic model time delay
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A Novel Statistical Delay Model Based on the Birnbaum-Saunders Distribution for RLC Interconnects in 90nm Technologies
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作者 周磊 孙玲玲 蒋立飞 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第7期1313-1317,共5页
For performance optimization such as placement,interconnect synthesis,and routing, an efficient and accurate interconnect delay metric is critical,even in design tools development like design for yield (DFY) and des... For performance optimization such as placement,interconnect synthesis,and routing, an efficient and accurate interconnect delay metric is critical,even in design tools development like design for yield (DFY) and design for manufacture (DFM). In the nanometer regime, the recently proposed delay models for RLC interconnects based on statistical probability density function (PDF)interpretation such as PRIMO,H-gamma,WED and RLD bridge the gap between accuracy and efficiency. However, these models always require table look-up when operating. In this paper, a novel delay model based on the Birnbaum-Saunders distribution (BSD) is presented. BSD can accomplish interconnect delay estimation fast and accurately without table look-up operations. Furthermore, it only needs the first two moments to match. Experimental results in 90nm technology show that BSD is robust, easy to implement,efficient,and accurate. 展开更多
关键词 delay model INTERCONNECT MOMENT probability distribution function
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Numerical simulation of flow regions in red mud separation thickener's feedwell by analysis of residence-time distribution 被引量:4
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作者 周天 李茂 +3 位作者 李秋龙 雷波 周谦 周孑民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1117-1124,共8页
The residence-time distribution (RTD) and the compartment model were applied to characterizing the flow regions in red mud separation thickener’s feedwells. Combined with the experimental work, validated mathematic... The residence-time distribution (RTD) and the compartment model were applied to characterizing the flow regions in red mud separation thickener’s feedwells. Combined with the experimental work, validated mathematical model as well as three-dimensional computational fluid dynamics (CFD) model was established to analyze the flow regions of feedwells on an industrial scale. The concept of RTD, although a well-known method for the characterization of mixing behavior in conventional mixers and reactors, is still a novel measure for the characterization of mixing in feedwells. Numerical simulation results show that the inlet feed rate and the aspect ratio of feedwells are the most critical parameters which affect the RTD of feedwell. Further simulation experiments were then carried out. Under the optimal operation conditions, the volume fraction of dead zone can reduce by10.8% and an increasement of mixing flow volume fraction by 6.5% is also observed. There is an optimum feed inlet rate depending on the feedwell design. The CFD model in conjunction with the RTD analysis then can be used as an effective tool in the design, evaluation and optimization of thickener feedwell in the red mud separation. 展开更多
关键词 computational fluid dynamics residence-time distribution compartment model feedwell
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Modeling of temperature-humidity for wood drying based on time-delay neural network 被引量:5
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作者 张冬妍 孙丽萍 曹军 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第2期141-144,共4页
The temperature-humidity models of wood drying were developed based on Time-delay neural network and the identification structures of Time-delay neural network were given. The controlling model and the schedule model,... The temperature-humidity models of wood drying were developed based on Time-delay neural network and the identification structures of Time-delay neural network were given. The controlling model and the schedule model, which revealed the relation between controlling signal and temperature-humidity and the relation between wood moisture content and temperature-humidity of wood drying, were separately presented. The models were simulated by using the measured data of the experimental drying kiln. The numerical simulation results showed that the modeling method was feasible, and the models were effective. 展开更多
关键词 Wood drying Temperature-humidity model System identification Time-Delay neural network
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Fine-Grain Sleep Transistor Insertion for Leakage Reduction
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作者 杨华中 汪玉林 +1 位作者 海罗嵘 汪蕙 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2006年第2期258-265,共8页
A fine-grain sleep transistor insertion technique based on our simplified leakage current and delay models is proposed to reduce leakage current. The key idea is to model the leakage current reduction problem as a mix... A fine-grain sleep transistor insertion technique based on our simplified leakage current and delay models is proposed to reduce leakage current. The key idea is to model the leakage current reduction problem as a mixed-integer linear programming (MLP) problem in order to simultaneously place and size the sleep transistors optimally. Because of better circuit slack utilization, our experimental results show that the MLP model can save leakage by 79.75%, 93.56%, and 94.99% when the circuit slowdown is 0%, 3%, and 5%, respectively. The MLP model also achieves on average 74.79% less area penalty compared to the conventional fixed slowdown method when the circuit slowdown is 7%. 展开更多
关键词 leakage current reduction fine-grain sleep transistor insertion delay model mixed-integer linearprogramming
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Prediction and Analysis of O_3 based on the ARIMA Model 被引量:2
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作者 李双金 杨宁 +2 位作者 闫奕琪 曹旭东 冀德刚 《Agricultural Science & Technology》 CAS 2015年第10期2146-2148,共3页
The research conducted prediction on changes of atmosphere pollution during July 9, 2014-July 22, 2014 with SPSS based on monitored data of O3 in 13 successive weeks from 6 sites in Baoding City and demonstrated predi... The research conducted prediction on changes of atmosphere pollution during July 9, 2014-July 22, 2014 with SPSS based on monitored data of O3 in 13 successive weeks from 6 sites in Baoding City and demonstrated prediction effect of ARIMA model is good by Ljung-Box Q-test and R2, and the model can be used for prediction on future atmosphere pollutant changes. 展开更多
关键词 Air quality Analysis of time series SPSS ARIMA model
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Scheduling method for single-arm cluster tools of wafer fabrications with residency and continuous reentrancy 被引量:2
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作者 周炳海 王翥 陈佳 《Journal of Southeast University(English Edition)》 EI CAS 2013年第2期187-193,共7页
In order to enhance the utilization of single-ann cluster tools and optimize the scheduling problems of dynamic reaching wafers with residency time and continuous reentrancy constraints, a structural heuristic schedul... In order to enhance the utilization of single-ann cluster tools and optimize the scheduling problems of dynamic reaching wafers with residency time and continuous reentrancy constraints, a structural heuristic scheduling algorithm is presented. A nonlinear programming scheduling model is built on the basis of bounding the scheduling problem domain. A feasible path search scheduling method of single-arm robotic operations is put forward with the objective of minimal makespan. Finally, simulation experiments are designed to analyze the scheduling algorithms. Results indicate that the proposed algorithm is feasible and valid to solve the scheduling problems of multiple wafer types and single-ann clusters with the conflicts and deadlocks generated by residency time and continuous reentrancy constraints. 展开更多
关键词 cluster tools SCHEDULING residency time continuous reentrancy
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Existence of Periodic Solutions of Nonlinear Neutral Differential Equation with Deviating Argument
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作者 任景莉 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2002年第4期439-443,共5页
Existence criteria is established for the periodic solution of the nonlinear neutral delay differential equation x′(t)=f(t,x(t),x(t-τ 1(t)),x′(t-τ 2(t)))+p(t) by means of an abstract continuous theorem of k-set ... Existence criteria is established for the periodic solution of the nonlinear neutral delay differential equation x′(t)=f(t,x(t),x(t-τ 1(t)),x′(t-τ 2(t)))+p(t) by means of an abstract continuous theorem of k-set contractive operator and some analysis technique. 展开更多
关键词 neutral delay differential equation periodic solution Fredholm operator k-set contractive operator
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Approach to adaptive service matchmaking
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作者 陈旺虎 韩燕波 +2 位作者 王菁 刘晨 王建武 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期408-412,共5页
To make service matchmaking more adaptive to various service requests and diverse web services, an adaptive approach-ASMA is proposed to service matchmaking based on temporal logic model-checking. The approach is base... To make service matchmaking more adaptive to various service requests and diverse web services, an adaptive approach-ASMA is proposed to service matchmaking based on temporal logic model-checking. The approach is based on the proposed abstract service model, ASM-TL, which addresses some important constraints for identifying capabilities of web services, such as service inner constraints and invocation constraints, and also has a virtual process model for describing service behavioral properties. By treating service requests as temporal logic conditions and web services as temporal models, ASMA does service matchmaking through model checking. Therefore, ASMA makes service matchmaking more accurate and more adaptive to the variety of service requests and the diversity of web services. The approach has been applied to the problem solving environment (PSE) for bioinformatics research. Applications show that the approach is suitable for dynamic environments. 展开更多
关键词 service matchmaking service model model checking temporal logic
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Fast Analysis of Power/Ground Networks via Circuit Reduction 被引量:1
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作者 蔡懿慈 潘著 +2 位作者 Sheldon X D Tan 洪先龙 傅静静 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2005年第7期1340-1346,共7页
This paper presents an efficient algorithm for reducing RLC power/ground network complexities by exploitation of the regularities in the power/ground networks. The new method first builds the equivalent models for man... This paper presents an efficient algorithm for reducing RLC power/ground network complexities by exploitation of the regularities in the power/ground networks. The new method first builds the equivalent models for many series RLC-current chains based on their Norton's form companion models in the original networks,and then the precondition conjugate gradient based iterative method is used to solve the reduced networks,which are symmetric positive definite. The solutions of the original networks are then back solved from those of the reduced networks.Experimental results show that the complexities of reduced networks are typically significantly smaller than those of the original circuits, which makes the new algorithm extremely fast. For instance, power/ground networks with more than one million branches can be solved in a few minutes on modern Sun workstations. 展开更多
关键词 circuit simulation power/ground network model reduction RLC circuit
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A Method for Detecting Adhesive Related-Factors of Streptococcus suis Serotype 2 by Real-time PCR 被引量:1
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作者 汪伟 何孔旺 +9 位作者 倪艳秀 周俊明 张雪寒 俞正玉 吕立新 茅爱华 温立斌 王小敏 李彬 郭容莉 《Agricultural Science & Technology》 CAS 2013年第10期1378-1382,共5页
[Objective] This study aimed to establish a method for quantitative detection of mRNA transcriptional level of SS2 adhesive related-factors of Streptococcus suis serotype 2 (SS2) by fluorescent quantitative PCR. []V... [Objective] This study aimed to establish a method for quantitative detection of mRNA transcriptional level of SS2 adhesive related-factors of Streptococcus suis serotype 2 (SS2) by fluorescent quantitative PCR. []Vlethod] The gene fragments en- coding SS2 adhesive related-factors MRP, FBPS and CPS2J and a housekeeping gene aroA were amplified by reverse transcription PCR from the total RNA of SS2, cloned, and sequenced. The recombinant plasmids containing the target genes were constructed, and used as templates in Real-time PCR. [Result] Dynamic curves, stan- dard curves and melting curves of the adhesive related-factors and aroA were ob- tained by the optimized Real-time PCR system. The standard curves showed a good linear relationship between template copy number and circulation number, and the correlation coefficients (FF) of the standard curves were over 0.995. Also, these as- says were highly specific a^d there was single specific melting peak for every gene. Moreover, the assays were highly sensitive and had a detection limit of 1.0×102 copies in 1 μl of initial templates. Finally, it was highly repeatable and had a coeffi- cient of variation less than 2% for intra-assay. [Conclusion] This study will provide a way to reveal the adhesion mechanism of SS2 to different host cells at molecular level. 展开更多
关键词 Streptococcus suis serotype 2 Adhesive related-factors (adhesins) Real- time PCR
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A NEW ELECTRON IMPACT STORAGE ION SOURCE 被引量:1
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作者 徐贞林 田锡惠 《Transactions of Tianjin University》 EI CAS 1995年第2期138+133-137,共6页
A new electron impact storage ion source has been designed for time of flight mass spectrometers with a high mass resolving power and high sensitivity. Because of the storage and compressing focus of the source, the o... A new electron impact storage ion source has been designed for time of flight mass spectrometers with a high mass resolving power and high sensitivity. Because of the storage and compressing focus of the source, the overall performance of the instrument has been improved greatly with a mass resolving power up to 3 500. The conditions of the second order of the focus are given and the storage ability is proved. The competer simulations and experiment results are given, too. 展开更多
关键词 electron impact ion source time of flight mass spectrometer
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TIME SERIES NEURAL NETWORK MODEL FOR HYDROLOGIC FORECASTING 被引量:4
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作者 钟登华 刘东海 Mittnik Stefan 《Transactions of Tianjin University》 EI CAS 2001年第3期182-186,共5页
Time series analysis plays an important role in hydrologic forecasting,while the key to this analysis is to establish a proper model.This paper presents a time series neural network model with back propagation proced... Time series analysis plays an important role in hydrologic forecasting,while the key to this analysis is to establish a proper model.This paper presents a time series neural network model with back propagation procedure for hydrologic forecasting.Free from the disadvantages of previous models,the model can be parallel to operate information flexibly and rapidly.It excels in the ability of nonlinear mapping and can learn and adjust by itself,which gives the model a possibility to describe the complex nonlinear hydrologic process.By using directly a training process based on a set of previous data, the model can forecast the time series of stream flow.Moreover,two practical examples were used to test the performance of the time series neural network model.Results confirm that the model is efficient and feasible. 展开更多
关键词 hydrologic forecasting time series neural network model back propagation
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Asymptotic Behavior and Nonexistence of Positive Solutions of Delay Difference Equations *L
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作者 彭名书 徐千里 《Journal of Beijing Institute of Technology》 EI CAS 1999年第1期25-30,共6页
Aim To obtain new criteria for asymptotic behavior and nonexistence of positive solutions of nonlinear neutral delay difference equations. Methods By means of Hlder inequality and a method of direct analysis, some i... Aim To obtain new criteria for asymptotic behavior and nonexistence of positive solutions of nonlinear neutral delay difference equations. Methods By means of Hlder inequality and a method of direct analysis, some interesting Lemmas were offered. Results and Conclusion New criteria for asymptotic behavior and nonexistence of positive solutions of nonlinear neutral delay difference equations are established, which extend and improve the results obtained in the literature. Some interesting examples illustrating the importance of our results are also included. 展开更多
关键词 OSCILLATION asymptotic behavior positive solution neutral delay difference equation NONLINEARITY
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On-body propagation characterization based on FDTD method for 2.4/5.2/5.7 GHz wearable body sensor networks 被引量:1
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作者 鲍淑娣 沈连丰 张元亭 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期151-155,共5页
The on-body path loss and time delay of radio propagation in 2. 4/5.2/5.7 GHz wearable body sensor networks (W-BSN) are studied using Remcom XFDTD, a simulation tool based on the finite-difference time- domain metho... The on-body path loss and time delay of radio propagation in 2. 4/5.2/5.7 GHz wearable body sensor networks (W-BSN) are studied using Remcom XFDTD, a simulation tool based on the finite-difference time- domain method. The simulation is performed in the environment of free space with a simplified three- dimensional human body model. Results show that the path loss at a higher radio frequency is significantly smaller. Given that the transmitter and the receiver are located on the body trunk, the path loss relevant to the proposed minimum equivalent surface distance follows a log-fitting parametric model, and the path loss exponents are 4. 7, 4. 1 and 4. 0 at frequencies of 2. 4, 5.2, 5.7 GHz, respectively. On the other hand, the first- arrival delays are less than 2 ns at all receivers, and the maximum time delay spread is about 10 ns. As suggested by the maximum time delay spread, transmission rates of W-BSN must be less than 10^8 symbol/s to avoid intersymbol interference from multiple-path delay. 展开更多
关键词 channel model path loss time delay characteristics wearable body sensor network
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Uniform asymptotics for finite-time ruin probability in some dependent compound risk models with constant interest rate 被引量:1
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作者 杨洋 刘伟 +1 位作者 林金官 张玉林 《Journal of Southeast University(English Edition)》 EI CAS 2014年第1期118-121,共4页
Consider two dependent renewal risk models with constant interest rate. By using some methods in the risk theory, uniform asymptotics for finite-time ruin probability is derived in a non-compound risk model, where cla... Consider two dependent renewal risk models with constant interest rate. By using some methods in the risk theory, uniform asymptotics for finite-time ruin probability is derived in a non-compound risk model, where claim sizes are upper tail asymptotically independent random variables with dominatedly varying tails, claim inter-arrival times follow the widely lower orthant dependent structure, and the total amount of premiums is a nonnegative stochastic process. Based on the obtained result, using the method of analysis for the tail probability of random sums, a similar result in a more complex and reasonable compound risk model is also obtained, where individual claim sizes are specialized to be extended negatively dependent and accident inter-arrival times are still widely lower orthant dependent, and both the claim sizes and the claim number have dominatedly varying tails. 展开更多
关键词 compound and non-compound risk models finite-time ruin probability dominatedly varying tail uniformasymptotics random sums dependence structure
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