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时间的构成与认知:杰尔的时间人类学理论内核述论 认领
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作者 木粲成 贾仲益 《民族学刊》 CSSCI 北大核心 2020年第1期83-93,141-142共13页
人类的时间观念何以异同是人类学时间研究的一个基本论题。对时间构成与时间认知的理解则左右着人类学家们对此论题的探究。20世纪90年代初,英国人类学家阿尔弗雷德·杰尔在继承与批判既往人类学家之时间论的基础上,综合多学科知识... 人类的时间观念何以异同是人类学时间研究的一个基本论题。对时间构成与时间认知的理解则左右着人类学家们对此论题的探究。20世纪90年代初,英国人类学家阿尔弗雷德·杰尔在继承与批判既往人类学家之时间论的基础上,综合多学科知识,析分出了作为事件之先后次序的客观时间("B系列"时间),作为过去、现在、未来意识的主观时间("A系列"时间),以及由主观时间模拟客观时间而生成的时间地图,并基于三者关系构建了一种普世的时间认知机制。杰尔认为,人类的时间认知作为人类基本认知机制运作的一种附带结果,在机制上具有普同性,而时间地图的内容则会随着人类经验与实践而变化,因此,人类学的时间研究应以时间认知机制之普同性为基础,注重探究时间地图之内容差异的社会文化根由。杰尔对时间的构成与认知的讨论是其时间人类学的理论内核,本文对其由来、内涵与缺陷进行了述论,以供后续研究参考。 展开更多
关键词 时间 认知 杰尔 时间人类学 “A系列”时间 “B系列”时间 时间地图
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Transient Stability Analysis of 33 KV Transmission Network of Egi Community, Nigeria 认领
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作者 Promise Elechi Christopher Okwuchukwu Ahiakwo Ugochukwu Nureedin Okwu 《电力能源(英文)》 2020年第3期18-35,共18页
Transient analysis of 33 KV power transmission line stability of Egi communi-ty is considered in this research work with the aim of reducing the frequency of fault occurrence and voltage collapse in the network. The s... Transient analysis of 33 KV power transmission line stability of Egi communi-ty is considered in this research work with the aim of reducing the frequency of fault occurrence and voltage collapse in the network. The supply is taken from Egi generating station located at Total Nigeria Limited Gas Plant Obite at voltage level of 33 KV to Egi communities. This work focuses on the transient nature of network stability since transient fault is the most dangerous in elec-trical systems. The swinging of the generator rotor in the event of transient three-phase short circuit fault can be monitored by the circuit breakers and the protective relays which causes mal-functioning of the circuit breakers and pro-tective relays leading to abnormal behavior of the network. Therefore, data obtained from the power station were used as a case study of Independent Power Producer (IPP) in Nigeria. For investigation of the power angle, angular velocity, rotor angle differential changes, and angular velocity differential changes, an electrical transient analyzer tool was employed (ETap version 16.00) for circuit breaker and protective relay time setting of (0.00, 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60). The work used the Trapezoidal numerical technique for data analysis. The graphs were plotted using Matlab R2015a and the results obtained showed that when a symmetrical three-phase short circuit fault occur at one or any of the feeders, the fault must be cleared as quick as possible through the coordination of the circuit breakers and protective relays. For this research work, 17 cycles corresponding to relay time setting of t = 0.34 s were recommended and at each cycle, changes in time with respect to changes in rotor angle, angular velocity, rotor differential and angular velocity differential were calculated on the power network simultaneously. The results demonstrated that the Trapezoidal method is numerically stable, accurate and has faster respond time when compared to Modified Euler and swing equat 展开更多
关键词 ROTOR Angle Transient Stability SWING Equation ANGULAR Speed Differential Changes Trapezoidal RULE Fault CLEARING TIME Critical CLEARING TIME
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An overview on GNSS carrier-phase time transfer research 认领
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作者 ZHANG Ming Lü JinHu +2 位作者 BAI ZhengDong JIANG ZhiQi CHEN BoBo 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2020年第4期589-596,共8页
Global navigation satellite system(GNSS)carrier phase observations are two orders of higher accuracy than pseudo-range observations,and they are less affected by multipath besides.As a result,the time transfer accurac... Global navigation satellite system(GNSS)carrier phase observations are two orders of higher accuracy than pseudo-range observations,and they are less affected by multipath besides.As a result,the time transfer accuracy can reach 0.1 ns,and the frequency transfer stability can reach 1×10^-15 with carrier phase(CP)method,therefore CP method is considered the most accurate and promising time transfer technology.The focus of this paper is to present a comprehensive summary of CP method,with specific attention directed toward day-boundary clock jump,ambiguity resolution(AR),multi-system time transfer and real-time time transfer.Day-boundary clock jump is essentially caused by pseudo-range noise.Several approaches were proposed to solve the problem,such as continuously processing strategy,sliding batch and bidirectional filtering methods which were compared in this study.Additionally,researches on AR in CP method were introduced.Many scholars attempted to fix the single-difference ambiguities to improve the time transfer result,however,owing to the uncalibrated phase delay(UPD)was not considered,the current studies on AR in CP method were still immature.Moreover,because four GNSS systems could be used for time-transfer currently,which was helpful to increase the accuracy and reliability,the researches on multi-system time transfer were reviewed.What’s more,real-time time transfer attracted more attention nowadays,the preliminary research results were presented. 展开更多
关键词 carrier phase(CP) TIME TRANSFER day-boundary clock jump AMBIGUITY resolution(AR) MULTI-SYSTEM TIME TRANSFER real-time TIME TRANSFER
文章速递Precursive Time, the Hidden Variable 认领
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作者 Renè Burri 《应用数学与应用物理(英文)》 2020年第6期1135-1154,共20页
In this paper, a new complex variable defined as “precursive time” able to correlate general relativity (GR) and quantum field theory (QFT) in a single principle was characterized. The thesis was elaborated accordin... In this paper, a new complex variable defined as “precursive time” able to correlate general relativity (GR) and quantum field theory (QFT) in a single principle was characterized. The thesis was elaborated according to a hypothesis coherent with the “Einstein’s General Theory of Relativity”, making use of a new mathematical-topological variety called “time-space” developed on the properties of the hypersphere and explained mathematically through the quaternion of Hurwitz-Lipschitz algebra. In this publication we pay attention to the interaction between the weak nuclear force theory (EWT) and the nuclear mass of the Standard Model. 展开更多
关键词 Time Curvature Precursive Time Hidden Variable Timespace Manifold Chronotope Quantum Compensation Spacetime
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文章速递Event-Triggered Finite-Time <i>H</i><sub>∞</sub>Control for Switched Stochastic Systems 认领
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作者 Aiqing Zhang 《应用数学与应用物理(英文)》 2020年第10期2103-2114,共12页
This paper investigates the problem of event-triggered finite-time <i>H</i><sub>∞</sub> control for a class of switched stochastic systems. The main objective of this study is to design an eve... This paper investigates the problem of event-triggered finite-time <i>H</i><sub>∞</sub> control for a class of switched stochastic systems. The main objective of this study is to design an event-triggered state feedback <i>H</i><sub>∞</sub> controller such that the resulting closed-loop system is finite-time bounded and satisfies a prescribed <i>H</i><sub>∞</sub> level in some given finite-time interval. Based on stochastic differential equations theory and average dwell time approach, sufficient conditions are derived to ensure the finite-time stochastic stability with the prescribed <i>H</i><sub>∞</sub> performance for the relevant closed-loop system by employing the linear matrix inequality technique. Finally, the desired state feedback <i>H</i><sub>∞</sub> controller gain matrices can be expressed in an explicit form. 展开更多
关键词 Average Dwell Time Event-Triggering Scheme Finite-Time Stochastic Stability (FTSS) Linear Matrix Inequalities (LMIS) Switched Stochastic Systems
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文章速递Two Problems of Time Entering Respectively the Relativistic Mechanics and Electron Transport in Quantum Theory 认领
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作者 Stanisław Olszewski 《力学国际期刊(英文)》 2020年第10期186-197,共12页
In the relativistic mechanics, we calculate a minimal distance between the time scale of a one-dimensional motion having a larger velocity and the time scale of a similar motion with a lower velocity. Concerning the q... In the relativistic mechanics, we calculate a minimal distance between the time scale of a one-dimensional motion having a larger velocity and the time scale of a similar motion with a lower velocity. Concerning the quantum theory, we demonstrate that mechanical parameters entering the electron motion in the Bohr hydrogen atom can provide us with a correct size of the time interval entering the Joule-Lenz law for the emission energy between two neighbouring quantum levels of the atom. 展开更多
关键词 Time in the Special Relativity Theory Time in the Quantum Theory of the Bohr Atom Joule-Lenz Law for the Emission of Energy in the Atom
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从政策公布到生效:政策实施的时间差分析 认领
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作者 曹佳 《公共行政评论》 CSSCI 北大核心 2020年第5期144-159,208,209,共18页
【问题】时间在公共政策中既是背景因素,也是研究工具,甚至是影响政策结果的关键变量。政策公布到生效之间事实上存在政策实施时间差,其长短的设置反映了决策者的理性思考和判断。不同时间差设置背后的影响因素是什么?【方法】论文提出... 【问题】时间在公共政策中既是背景因素,也是研究工具,甚至是影响政策结果的关键变量。政策公布到生效之间事实上存在政策实施时间差,其长短的设置反映了决策者的理性思考和判断。不同时间差设置背后的影响因素是什么?【方法】论文提出一个对政策实施时间差的分析框架,并选取广州汽车限购的地方性政策和“单独二孩”的全国性政策作为对比案例,具体分析框架中的主要影响因素及其影响方向。【发现】时间在公共政策过程中既是一种投入也是一种产出,是一个内生性的存在;时间策略在公共政策领域具有一般的普遍性和重要性;决策者会策略性地设置时间差,以回应政策特征、政策执行主体、政策目标群体和政策环境等因素对政策的约束,最大化政策效果。【贡献】研究深化和发展对公共政策中的时间的讨论;首次探讨了政策公布与生效的时间差,将其作为结果,揭示了决定其长短的决策理性和影响因素;丰富和发展了政策过程理论。 展开更多
关键词 时间 时间差 时间策略 政策公布 政策生效
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Experimental Study of a Metallic Pressure Cooker Insulated with Kapok Wool 认领
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作者 Drissa Ouedraogo Serge Wendsida Igo +3 位作者 Abdoulaye Compaore Gae?l Lassina Sawadogo Belkacem Zeghmati Xavier Chesneau 《能源与动力工程(英文)》 2020年第2期73-87,共15页
This work is devoted to an experimental study of metallic pressure cooker insulated with kapok wool, a vegetal biodegradable fiber. Experiments conducted on the cooling of hot water in the equipment revealed very low ... This work is devoted to an experimental study of metallic pressure cooker insulated with kapok wool, a vegetal biodegradable fiber. Experiments conducted on the cooling of hot water in the equipment revealed very low heat losses and a time constant of 60 hours on average. As a result, the equipment makes it possible to finish cooking meals only thanks to the heat stored at the beginning of cooking and keeps cooked dishes warm for long hours. The thermal phase shift of the pressure cooker is around 7?h. Cooking tests conducted on some local dishes revealed about 70% butane gas savings for cooking cowpea and white rice, 38% for cooking fatty rice, 75% for pasta and couscous, and 30% for cooking potato stew. These results show that this technology can contribute to minimizing?energy consumption in the restaurant sector. 展开更多
关键词 Pressure COOKER KAPOK WOOL Time Constant Energy SAVING RESTAURANT SECTOR
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The Chemical Channel of Earthquake Reactions and Decrease in the Magnitude of Earthquakes 认领
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作者 Michael G. Noppe 《地球科学国际期刊(英文)》 2020年第3期84-99,共16页
The first necessary condition for the onset of an earthquake is the penetration of explosive gas into an explosive zone as a result of physical or chemical reaction. The second necessary condition is to ensure the sub... The first necessary condition for the onset of an earthquake is the penetration of explosive gas into an explosive zone as a result of physical or chemical reaction. The second necessary condition is to ensure the subsequent propagation of the flame after ignition. The latter condition has made it possible to explain the impact of a cyclone on the emergence of 42 strongest earthquakes in the 21st century. If violation of this condition can be achieved with the help of vibrators or explosions, this will result in a decrease in the magnitude of an earthquake or even a complete prevention of earthquakes. Thus, the second condition is essentially a “pressure lock” that opens (with a decrease in the pressure caused by a cyclone), which leads to an earthquake or closes (with an increase in the pressure caused by an anticyclone or human interference using vibrators or explosions), which leads to earthquake prevention. Kinetic equations of the 2nd type were used to describe chemical reactions and obtain formulas for the precursor time, which made it possible to describe earthquakes of the chemical channel. The set of experimental time values of the earthquake precursor described by the physical model includes about 20% of all earthquakes;80% of earthquakes can be attributed to the chemical channel for earthquakes that occurred in Dushanbe in 1983. All earthquakes in Tiberias in June 2018 passed through the chemical channel, which can be concluded from the small magnitude of these earthquakes. Several proposals have been made, including: 1) creating a new sensor for the geochemical method, which allows determining the epicenter of a future earthquake;2) creating a network of stations with a new sensor for determining the epicenter and an atmospheric pressure meter installed at each station (this will determine if the “pressure lock” is closed by an anticyclone, which can lead to a decrease in the magnitude of an earthquake or even prevent an earthquake);3) installing vibrators in epicenters (or making daily explos 展开更多
关键词 EARTHQUAKES Prediction Physical Model EARTHQUAKE Condition Precursor Time Formula Kinetic Equations for CHEMICAL REACTIONS Necessary Conditions for EARTHQUAKE
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The Novel Current Control for Virtual Synchronous Generator 认领
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作者 Atsushi Umemura Rion Takahashi Junji Tamura 《电力能源(英文)》 2020年第2期78-89,共12页
In recent years, power generation using renewable energy sources has been developed as a solution to the global warming problem. Among these power generation methods, wind power generation is increasing. However, as t... In recent years, power generation using renewable energy sources has been developed as a solution to the global warming problem. Among these power generation methods, wind power generation is increasing. However, as the penetration level of wind power generation increases, the low inertia and lack of synchronous power characteristics of the penetrated power system can have a significant impact on the transient stability of the grid. The virtual synchronous generator provides the ability of virtual inertia and synchronous power to interconnected inverters. The interconnected inverter with the virtual synchronous generator ability uses, in general, PI control based current controller. This paper proposes a new current-control method and compares it with conventional methods. The proposed current control is a method that follows virtual synchronous generator model that changes every moment by solving the discrete-time linear quadratic optimal control problem for each sampling time interval. The new method follows the conventional method, and therefore the reactive power fluctuation can be suppressed and the interconnected inverter will be downsized. 展开更多
关键词 Wind Energy Generation State FEEDBACK Electric Current CONTROL LINEARIZATION Techniques DISCRETE Time Model Following CONTROL Virtual SYNCHRONOUS GENERATOR
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Value of High-Frequency Relic Gravitational Wave (HFRGW) Detection to Astrophysics and Fabrication and Utilization of the Li-Baker HFRGW Detector 认领
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作者 Andrew Walcott Beckwith Robert M. L. Baker Jr 《高能物理(英文)》 2020年第1期103-122,共20页
Up to the present time gravitational-wave detectors, such as LIGO and Virgo, have been sensitive to frequencies on the order of a few thousand to a small fraction of an Hz. They have been most effective in the study o... Up to the present time gravitational-wave detectors, such as LIGO and Virgo, have been sensitive to frequencies on the order of a few thousand to a small fraction of an Hz. They have been most effective in the study of black-hole mergers. We suggest that high-frequency relic gravitational wave (HFRGW) detectors be developed, especially the Li-Baker HFRGW detector, in the gigahertz and higher frequency range. We believe collecting cosmological, primordial observational data especially generated during the first few seconds after the beginning of our Universe is extremely important. One motivation for this paper is, therefore, that we are confident that observation of relic gravitational waves will provide vital information about the birth of our Universe and its early dynamical evolution. Other astrophysical applications of HFRGW detectors involve the entropy growth of the early Universe, an ability to study alternatives to inflation and to provide clues about the symmetries underlying new physics at the highest energies. A working hypothesis or theory, based upon the rollout of our Universe from infinitesimal Planck Length and Planck Time is presented. This theory involves the rapid motion of time and matter during that early time having frequencies on the order of trillions of cycles per second or more. Several alternative HFRGW detectors are described and the proposed Li-Baker HFRGW detector, which is theoretically sensitive to GW amplitudes, A, as small as 10-32, is discussed in detail. Such sensitivity may provide a means for verifying or falsifying the rollout of our Universe working hypothesis. Essentially a combination of theory and experimentation is presented. It is recommended that plans and detailed specifications for the Li-Baker HFRGW detector be prepared in order to expedite its fabrication. 展开更多
关键词 HIGH-FREQUENCY GRAVITATIONAL Waves DARK Energy DARK Matter Variation of Speed of Time Beyond the Standard Model of COSMOLOGY Early UNIVERSE
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Ehrenfest Approach to the Adiabatic Invariants and Calculation of the Intervals of Time Entering the Energy Emission Process in Simple Quantum Systems 认领
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作者 Stanis?aw Olszewski 《量子信息科学期刊(英文)》 2020年第1期1-9,共9页
In the first step, the Ehrenfest reasoning concerning the adiabatic invariance of the angular orbital momentum is applied to the electron motion in the hydrogen atom. It is demonstrated that the time of the energy emi... In the first step, the Ehrenfest reasoning concerning the adiabatic invariance of the angular orbital momentum is applied to the electron motion in the hydrogen atom. It is demonstrated that the time of the energy emission from the quantum level n+1 to level n can be deduced from the orbital angular momentum examined in the hydrogen atom. This time is found precisely equal to the time interval dictated by the Joule-Lenz law governing the electron transition between the levels n+1 and n. In the next step, the mechanical parameters entering the quantum systems are applied in calculating the time intervals characteristic for the electron transitions. This concerns the neighbouring energy levels in the hydrogen atom as well as the Landau levels in the electron gas submitted to the action of a constant magnetic field. 展开更多
关键词 Aadiabatic INVARIANTS TIME of the Energy Emission PROCESS Referred to the Mechanical Parameters of a Quantum System Hydrogen Atom The LANDAU Levels in the Electron Gas
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DNA Sequencing Modified Method through Effective Regulation of Its Translocation Speed in Aqueous Solution 认领
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作者 Lusine Gasparyan Ilya Mazo +1 位作者 Ferdinand Gasparyan Vahan Simonyan 《生物物理学期刊(英文)》 2020年第2期96-112,共17页
Solid-state nanopore DNA sequencing modified method is developed. Method is based on the tunnel current investigation through the nanogap made on lateral gold electrodes in the form of nanowires or nanoribbons. The mo... Solid-state nanopore DNA sequencing modified method is developed. Method is based on the tunnel current investigation through the nanogap made on lateral gold electrodes in the form of nanowires or nanoribbons. The movement of DNA in aqueous solution is regulated by the potential applied to reference electrode. The potential applied to the lateral metal electrodes helps to the creation of the molecular junctions. They consist of the nucleosides passing through the pores. Taking into account that DNA moves under gravity, electrophoretic and drag forces, the analytic expression for the DNA translocation speed is calculated and analyzed. The conditions for decreasing the DNA translocation speed or increasing the nucleosides reading time are received. It is shown that one can control value of the DNA molecules bases reading time and the frequency of the bases passes by the choice of magnitude of the potential applied to reference electrode. Our results, therefore potentially suggest a realistic, inherently design-specific, high-throughput nanopore DNA sequencing device/cell as a de-novo alternative to the existing methods. 展开更多
关键词 DNA SEQUENCING DNA SPEED FORCES Reading Time
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“间”之演化:探析安藤忠雄作品中的三个概念 认领
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作者 刘宏勋 《设计艺术研究》 2020年第5期119-122,136,共5页
安藤忠雄代表性的清水混凝土建筑是建筑领域的独特存在。在安藤忠雄的作品中,空间、时间、时空概念始终贯穿其中,安藤忠雄将“间”的抽象化概念通过建筑这一媒介具体化,将自然元素纳入建筑呈现的范围。自然元素与建筑的智慧结合诠释“... 安藤忠雄代表性的清水混凝土建筑是建筑领域的独特存在。在安藤忠雄的作品中,空间、时间、时空概念始终贯穿其中,安藤忠雄将“间”的抽象化概念通过建筑这一媒介具体化,将自然元素纳入建筑呈现的范围。自然元素与建筑的智慧结合诠释“间”的概念,并将建筑作品的有限外延在精神上推向无限。 展开更多
关键词 安藤忠雄 建筑 空间 时间 时空
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An Analysis of Teacher Talk in an EFL Classroom 认领
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作者 刘娅琪 《海外英语》 2020年第14期271-275,共5页
In order to promote the efficiency of teachers’teaching and students’learning,based on the naturalistic inquiry,the study mainly describes the typical features of teacher talk.High quality language input rely on the... In order to promote the efficiency of teachers’teaching and students’learning,based on the naturalistic inquiry,the study mainly describes the typical features of teacher talk.High quality language input rely on the teaching materials and curricu⁃lum design,more importantly,it relies on the teacher talk to express and explain language knowledge.The teacher talk has an influ⁃ence on learners’learning attitude,classroom performance and the learning process.If used appropriately,the teacher talk can pro⁃mote the communication as well as inspire students to participate the classroom interaction. 展开更多
关键词 teacher talk EFL classroom teacher talk time student talk time teacher’s feedback
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Production of Oil-Free Crunchy Potato Chips Using Microwave 认领
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作者 Naglaa A. Shedeed El-Sayed A. Abd El-Hady Rehab A. ALoweis 《食品与营养科学(英文)》 2020年第1期40-51,共12页
The study was conducted to evaluate the effect of baking conditions of partially-dried potato slices (PDPS) prior baking on the quality attributes of the resultant baked potato chips. Baking experiment was conducted a... The study was conducted to evaluate the effect of baking conditions of partially-dried potato slices (PDPS) prior baking on the quality attributes of the resultant baked potato chips. Baking experiment was conducted at power levels of 80 and 100 Watts for different baking times according to microwave power used. Texture, color measurements and sensory evaluation were carried out on resultant baked potato chips. The results showed that partially drying step (even to 40% moisture content) prior microwave baking resulted in marked crispiness as well as brilliant yellow in resultant potato chips. The optimum conditions for the best quality of partially-dried potato chips were microwave cooking at power level of 100 Watts for 100 seconds. 展开更多
关键词 POTATO CHIPS Pre-Drying MICROWAVE BAKING BAKING Time SENSORY Properties
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Trans-Thoracic Echocardiographic Aortic Blood Flow Peak Velocity Variation, Distance Minute, Aortic Velocity Time Integral and Postoperative Outcome in Pediatric Surgical Patients—An Observational Pilot Study Protocol 认领
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作者 Claudine Kumba 《内科学期刊(英文)》 2020年第1期90-95,共6页
Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity vari... Background: A Randomized Controlled Trial (RCT) has been elaborated where goal directed fluid and hemodynamic therapy (GDFHT) will be realized with trans-thoracic echocardiographic aortic blood flow peak velocity variation (ΔVpeak) and distance minute (DM) to guide fluid therapy and hemodynamics in high risk pediatric surgical patients. This RCT will clarify the impact of GDFHT with ΔVpeak and DM on postoperative outcome in terms of morbidity, length of stay in the intensive care unit (LOSICU), length of mechanical ventilation (LMV) and length of hospital stay (LOS) in children. To determine values of ΔVpeak, DM and VTI predictive of these postoperative outcomes, an observational pilot study will be realized. This pilot study is described here. The primary objective of this study is to determine values of ΔVpeak, DM and ITV predictive of postoperative outcome in children in terms of morbidity. The secondary objectives are to determine values of ΔVpeak, DM and ITV predictive of LOSICU, LMV, LOS, intraoperative, postoperative fluid administration and vasoactive-inotropic therapy. Methods: 500 - 1000 children aged less than 18 years will be included prospectively. Statistic analysis will be realized with XLSTAT 2019.4.2 software or plus. Results and Conclusions: This trial protocol will determine values of ΔVpeak, DM and ITV with echocardiography predictive of postoperative outcome in children. 展开更多
关键词 Children AORTIC Blood Flow Peak VELOCITY Variation AORTIC VELOCITY Time INTEGRAL Distance MINUTE Postoperative Outcome Pilot Study Protocol Trans-Thoracic Echocardiography
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Will Crash Experience Affect Driver’s Behavior? An Observation and Analysis on Time Headway Variation Before and After a Traffic Crash 认领
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作者 Yun Yue Zi Yang +3 位作者 Xin Pei Hongxin Chen Chao Song Danya Yao 《清华大学学报:自然科学版(英文版)》 SCIE EI CAS CSCD 2020年第4期471-478,共8页
Research into the impact of road accidents on drivers is essential to effective post-crash interventions.However,due to limited data and resources,the current research focus is mainly on those who have suffered severe... Research into the impact of road accidents on drivers is essential to effective post-crash interventions.However,due to limited data and resources,the current research focus is mainly on those who have suffered severe injuries.In this paper,we propose a novel approach to examining the impact that being involved in a crash has on drivers by using traffic surveillance data.In traffic video surveillance systems,the locations of vehicles at different moments in time are captured and their headway,which is an important indicator of driving behavior,can be calculated from this information.It was found that there was a sudden increase in headway when drivers return to the road after being involved in a crash,but that the headway returned to its pre-crash level over time.We further analyzed the duration of the decay using a Cox proportional hazards regression model,which revealed many significant factors(related to the driver,vehicle,and nature of the accident)behind the survival time of the increased headway.Our approach is able to reveal the crash impact on drivers in a convenient and economical way.It can enhance the understanding of the impact of a crash on drivers,and help to devise more effective re-education programs and other interventions to encourage drivers who are involved in crashes to drive more safely in the future. 展开更多
关键词 CRASH impact driving behavior TIME HEADWAY survival TIME COX proportional hazards model
Design of Experiment (DoE): Implementation in Determining Optimum Design Parameters of Portable Workstation 认领
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作者 Nafisa Ali Anika Nadia Tanzeem Himadri Sen Gupta 《工程(英文)(1947-3931)》 2020年第1期25-32,共8页
In the modern era of manufacturing, it is important to optimize every design parameter in product development stage to reduce cost, material usage and to achieve the desired efficacy level. There are various models wh... In the modern era of manufacturing, it is important to optimize every design parameter in product development stage to reduce cost, material usage and to achieve the desired efficacy level. There are various models which serve those purposes, for instance, Design of Experiment (DoE) is used to check the parameters after adopting optimization tactics which results in reduced cost or saving operating time. In this regard, this research aims to construct a DoE model on a portable workstation to optimize its design parameters. The methodology of DOE would be a 2 level 3 factors full factorial DOE which is conducted to determine the optimal value for three design parameters (factors) which are material density, the length of the table and the length of the table stand in terms of the response which is the required time of fold ability function of the portable workstation. Based upon the evaluated interactions between the parameters, the optimized parameters are chosen for responses. Here, the resultant design parameters are at their lowest level, so the goal of time efficiency in fold ability function is achieved. This similar sort of DoE can be implemented in the furniture and other manufacturing industries who wish to optimize their material usage as well as increase efficiency and reduce cycle time. 展开更多
关键词 DESIGN of EXPERIMENT (DoE) PORTABLE WORKSTATION DESIGN Parameters Response Time Efficiency Improvement
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应用"TIME"原则与拉合加压治疗剖宫产术后腹部切口裂开的效果观察 认领
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作者 严乾淑 兰南 杨义芳 《国际护理学杂志》 2020年第11期2003-2006,共4页
目的:探讨应用"TIME"原则与拉合加压治疗剖宫产术后腹部切口裂开的效果。方法:选取该院2018年1~12月剖宫产术后腹部切口裂开产妇43例,将2018年1~6月剖宫产术后腹部切口裂开产妇20例设为对照组,由医生处理伤口;将2018年7~12月... 目的:探讨应用"TIME"原则与拉合加压治疗剖宫产术后腹部切口裂开的效果。方法:选取该院2018年1~12月剖宫产术后腹部切口裂开产妇43例,将2018年1~6月剖宫产术后腹部切口裂开产妇20例设为对照组,由医生处理伤口;将2018年7~12月剖宫产术后腹部切口裂开产妇23例设为观察组,由伤口护士应用"TIME"原则与拉合加压治疗伤口,观察组伤口愈合时间、换药次数、换药费用、患者满意度,比较两组平均住院日、平均住院费用。结果:观察组剖宫产术后腹部切口裂开通过应用"TIME"原则与拉合加压治疗,伤口愈合时间、换药次数,换药费用患者满意度,两组差异均有统计学意义(均P<0.05)。结论:应用"TIME"原则与拉合加压治疗剖宫产术后腹部切口裂开伤口,方法正确,患者对愈合时间、换药次数、换药费用都满意,减少了患者住院日和住院费用,值得推广到所有腹部手术后切口裂开伤口的治疗。 展开更多
关键词 "TIME" 拉合加压 剖宫产 腹部切口裂开 效果
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