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急性脑梗死溶栓治疗的时间窗选择与疗效分析 被引量:12
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作者 吕俊彬 《陕西医学杂志》 CAS 2013年第8期969-970,共2页
目的:探讨不同血压水平急性脑梗死患者溶栓治疗时间窗的选择及其临床疗效。方法:急性脑梗死患者84例均接受尿激酶溶栓治疗,剂量100~200万U。根据患者救治时的血压水平进行分组:A组(MABP≤90.0mmHg)16例,B组(90.0mmHg?MABP≤105.0mmHg)2... 目的:探讨不同血压水平急性脑梗死患者溶栓治疗时间窗的选择及其临床疗效。方法:急性脑梗死患者84例均接受尿激酶溶栓治疗,剂量100~200万U。根据患者救治时的血压水平进行分组:A组(MABP≤90.0mmHg)16例,B组(90.0mmHg?MABP≤105.0mmHg)22例,C组(105.0mmHg?MABP≤120.0)27例,D组(MABP<120.0mmHg)19例。根据发病时间分为:E组(治疗时发病时间<3h)14例,F组(治疗时发病时间3~6h)46例,G组(治疗时发病时间>6h且<9h)24例。治疗前后应用脑卒中量表(NIHSS)和Barthel指数对患者进行评定。结果:①溶栓后血管再通率:A组为50.0%,B组为81.8%,C组为77.8%,D组为57.9%,B、C两组血管再通率明显高于A、B两组(P?0.05)。②治疗前E、F、G组NIHSS评分和Barthel指数比较无统计学差异(P>0.05),治疗后24h,7d,21d各组NIHSS评分明显下降,Barthel指数明显提高,与治疗前比较有统计学差异(P<0.05);组间比较E组效果明显优于F组(P<0.05),G组比较无统计学差异(P>0.05)。结论:急性脑梗死溶栓治疗血管再通率与患者救治时血压水平有关,患者血压水平略高于理想血压,溶栓效果较好,但溶栓时间窗3~6h与6~9h疗效无明显差异。 展开更多
关键词 脑梗塞 治疗 血栓溶解疗法 @时间窗
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Vehicle routing optimization algorithm based on time windows and dynamic demand
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作者 LI Jun DUAN Yurong +1 位作者 ZHANG Weiwei ZHU Liyuan 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期369-378,共10页
To provide the supplier with the minimizum vehicle travel distance in the distribution process of goods in three situations of new customer demand,customer cancellation service,and change of customer delivery address,... To provide the supplier with the minimizum vehicle travel distance in the distribution process of goods in three situations of new customer demand,customer cancellation service,and change of customer delivery address,based on the ideas of pre-optimization and real-time optimization,a two-stage planning model of dynamic demand based vehicle routing problem with time windows was established.At the pre-optimization stage,an improved genetic algorithm was used to obtain the pre-optimized distribution route,a large-scale neighborhood search method was integrated into the mutation operation to improve the local optimization performance of the genetic algorithm,and a variety of operators were introduced to expand the search space of neighborhood solutions;At the real-time optimization stage,a periodic optimization strategy was adopted to transform a complex dynamic problem into several static problems,and four neighborhood search operators were used to quickly adjust the route.Two different scale examples were designed for experiments.It is proved that the algorithm can plan the better route,and adjust the distribution route in time under the real-time constraints.Therefore,the proposed algorithm can provide theoretical guidance for suppliers to solve the dynamic demand based vehicle routing problem. 展开更多
关键词 vehicle routing problem dynamic demand genetic algorithm large-scale neighborhood search time windows
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Improved ant colony optimization for multi-depot heterogeneous vehicle routing problem with soft time windows 被引量:10
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作者 汤雅连 蔡延光 杨期江 《Journal of Southeast University(English Edition)》 EI CAS 2015年第1期94-99,共6页
Considering that the vehicle routing problem (VRP) with many extended features is widely used in actual life, such as multi-depot, heterogeneous types of vehicles, customer service priority and time windows etc., a ... Considering that the vehicle routing problem (VRP) with many extended features is widely used in actual life, such as multi-depot, heterogeneous types of vehicles, customer service priority and time windows etc., a mathematical model for multi-depot heterogeneous vehicle routing problem with soft time windows (MDHVRPSTW) is established. An improved ant colony optimization (IACO) is proposed for solving this model. First, MDHVRPSTW is transferred into different groups according to the nearest principle, and then the initial route is constructed by the scanning algorithm (SA). Secondly, genetic operators are introduced, and crossover probability and mutation probability are adaptively adjusted in order to improve the global search ability of the algorithm. Moreover, the smooth mechanism is used to improve the performance of the ant colony optimization (ACO). Finally, the 3-opt strategy is used to improve the local search ability. The proposed IACO was tested on three new instances that were generated randomly. The experimental results show that IACO is superior to the other three existing algorithms in terms of convergence speed and solution quality. Thus, the proposed method is effective and feasible, and the proposed model is meaningful. 展开更多
关键词 vehicle routing problem soft time window improved ant colony optimization customer service priority genetic algorithm
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A signal coordination algorithm for two adjacent intersections based on approximate dynamic programming 被引量:1
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作者 别一鸣 王琳虹 +1 位作者 王殿海 马东方 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期112-118,共7页
To reduce vehicle emissions in road networks, a new signal coordination algorithm based on approximate dynamic programming (ADP) is developed for two intersections. Taking the Jetta car as an experimental vehicle, f... To reduce vehicle emissions in road networks, a new signal coordination algorithm based on approximate dynamic programming (ADP) is developed for two intersections. Taking the Jetta car as an experimental vehicle, field tests are conducted in Changchun Street of Changchun city and vehicle emission factors in complete stop and uniform speed states are collected. Queue lengths and signal light colors of approach lanes are selected as state variables, and green switch plans are selected as decision variables of the system. Then the calculation model of the optimization index during the planning horizon is developed based on the basis function method of the ADP. The temporal-difference algorithm is employed to update the weighting factor vector of the approximate function. Simulations are conducted in Matlab and the results show that the established algorithm outperforms the conventional coordination algorithm in reducing vehicle emissions by 8.2%. Sensitive analysis of the planning horizon length on the evaluation index is also conducted and the statistical results show that the optimal length of the planning horizon is directly proportional to the traffic load. 展开更多
关键词 signal coordination approximate dynamicprogramming vehicle emissions planning horizon
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Rolling horizon scheduling algorithm for dynamic vehicle scheduling system 被引量:1
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作者 贾永基 谷寒雨 席裕庚 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期92-96,共5页
Dynamic exclusive pickup and delivery problem with time windows (DE-PDPTW), aspecial dynamic vehicle scheduling problem, is proposed. Its mathematical description is given andits static properties are analyzed, and th... Dynamic exclusive pickup and delivery problem with time windows (DE-PDPTW), aspecial dynamic vehicle scheduling problem, is proposed. Its mathematical description is given andits static properties are analyzed, and then the problem is simplified asthe asymmetrical travelingsalesman problem with time windows. The rolling horizon scheduling algorithm (RHSA) to solve thisdynamic problem is proposed. By the rolling of time horizon, the RHSA can adapt to the problem'sdynamic change and reduce the computation time by dealing with only part of the customers in eachrolling time horizon. Then, its three factors, the current customer window, the scheduling of thecurrent customer window and the rolling strategy, are analyzed. The test results demonstrate theeffectiveness of the RHSA to solve the dynamic vehicle scheduling problem. 展开更多
关键词 dynamic vehicle scheduling rolling horizon scheduling algorithm EXCLUSIVE pickup and delivery problem with time windows (PDPTW)
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Diurnal Variation of Soil CO2 Efflux and Its Optimal Measuring Time-window of Temperate Meadow Steppes in Western Songnen Plain, China 被引量:2
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作者 YU Xiuli LI Xiujun +4 位作者 XU Linshu WANG Ming ZHANG Jitao JIANG Ming WANG Guodong 《Chinese Geographical Science》 SCIE CSCD 2016年第4期518-526,共9页
In order to study the diurnal variation of soil CO2 effiux from temperate meadow steppes in Northeast China, and determine the best time for observation, a field experiment was conducted with a LI-6400 soil CO2 flux s... In order to study the diurnal variation of soil CO2 effiux from temperate meadow steppes in Northeast China, and determine the best time for observation, a field experiment was conducted with a LI-6400 soil CO2 flux system under five typical plant communi- ties (Suaeda glauca (Sg), Chloris virgata (Cv), Puecinellia distans (Pd), Leymus chinensis (Lc) and Phragmites australis (Pa)) and an alkali-spot land (As) at the meadow steppe of western Songnen Plain. The results showed that the diurnal variation of soil CO2 effiux exhibited a single peak curve in the growing season. Diurnal maximum soil respiration (Rs) often appeared between 1 1:00 and 13:00, while the minimum occurred at 21:00-23:00 or before dawn. Air temperature near the soil surface (Ta) and soil temperature at 10 cm depth (Tlo) exerted dominant control on the diurnal variations of soil respiration. The time-windows 7:00-9:00 could be used as the optimal measuring time to represent the daily mean soil CO2 effiux at the Cv, Pd, Lc and Pa sites. The daily mean soil CO2 effiux was close to the soil COz effiux from 15:00 to 17:00 and the mean of 2 individual soil CO2 effiux from 15:00 to 19:00 at the As and Sg sites, respectively. During nocturnal hours, negative soil CO2 fluxes (CO2 downwards into the soil) were frequently observed at the As and Sg sites, the magnitude of the negative CO2 fluxes were 0.10-1.55 gmol/(m2.s) and 0.10-0.69 gmol/(m2.s)at the two sites. The results im- plied that alkaline soils could absorb CO2 under natural condition, which might have significant implications to the global carbon budget accounting. 展开更多
关键词 soil respiration CQ effiux meadow steppe optimal measurement time negative C02 effiux
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A GA approach to vehicle routing problem with time windows considering loading constraints 被引量:5
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作者 刘建胜 Luo Zhiwen +2 位作者 Duan Duanzhi Lai Zhihui Huang Jiali 《High Technology Letters》 EI CAS 2017年第1期54-62,共9页
As a new variant of vehicle routing problem( VRP),a finished vehicle routing problem with time windows in finished vehicle logistics( FVRPTW) is modeled and solved. An optimization model for FVRPTW is presented with t... As a new variant of vehicle routing problem( VRP),a finished vehicle routing problem with time windows in finished vehicle logistics( FVRPTW) is modeled and solved. An optimization model for FVRPTW is presented with the objective of scheduling multiple transport routes considering loading constraints along with time penalty function to minimize the total cost. Then a genetic algorithm( GA) is developed. The specific encoding and genetic operators for FVRPTW are devised.Especially,in order to accelerate its convergence,an improved termination condition is given. Finally,a case study is used to evaluate the effectiveness of the proposed algorithm and a series of experiments are conducted over a set of finished vehicle routing problems. The results demonstrate that the proposed approach has superior performance and satisfies users in practice. Contributions of the study are the modeling and solving of a complex FVRPTW in logistics industry. 展开更多
关键词 finished vehicle logistics (FVL) vehicle routing problem (VRP) genetic algo-rithm (GA) time windows
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Realization of 40 GHz Short Time Windows and Their Applications in High Speed Optical Time Division Multiplexing Systems 被引量:1
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作者 Li Yan Wu Jian 《China Communications》 SCIE CSCD 2012年第8期40-51,共12页
Optical Time Division Multiplexing (OTDM) is known to be capable of transmitting single channel high bit rate data stream with low speed electro-optical components. A cost-effective, compact and stable short time wi... Optical Time Division Multiplexing (OTDM) is known to be capable of transmitting single channel high bit rate data stream with low speed electro-optical components. A cost-effective, compact and stable short time window with low insert loss, low phase noise, low timing-jitter and high speed performance is essential for ultra-high speed OTDM systems using phase and amplitude modulation formats. In this paper, we review three promising methods to obtain 40 GHz short time window including Electro-Absorption Modulator (EAM), Dual-Parallel Mach-Zehnder Modulator (DPMZM) and Fiber Loop-Polarization Modulator (FL-PolM). Sub-picosecond short pulse source generation, optical time division denlaltiplexing and clock recovery are realized respectively by using the short time window based on the three methods. By using DPMZM based pulse source and EAM based Clock Recovery (CR) and dermltiplexer, error free transmission of 640 Goit/s (160 Gbaud/s Pol-Mux DQPSK) single channel signal over 400 km single mode fiber is proven to be experimentally successful. 展开更多
关键词 optical fiber conmmnication optical time division nmltiplexing optical tirre switch
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ERCP for the treatment of bile leak after partial hepatectomy and fenestration for symptomatic polycystic liver disease 被引量:6
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作者 Nayantara Coelho-Prabhu David M Nagorney Todd H Baron 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第28期3705-3709,共5页
AIM: To describe endoscopic treatment of bile leaks in these patients and to identify risk factors in these patients which can predict the development of bile leaks. METHODS: Retrospective case-control study examining... AIM: To describe endoscopic treatment of bile leaks in these patients and to identify risk factors in these patients which can predict the development of bile leaks. METHODS: Retrospective case-control study examining consecutive patients who underwent partial hepatectomy for polycystic liver disease (PLD) and developed a postoperative bile leak managed endoscopically over a ten year period. Each case was matched with two controls with PLD who did not develop a postoperative bile leak. RESULTS: Ten cases underwent partial hepatectomy with fenestration for symptoms including abdominal distention, pain and nausea. Endoscopic retrograde cholangiopancreatography (ERCP) showed anatomic abnormalities in 1 case. A biliary sphincterotomy was performed in 4 cases. A plastic biliary stent was placed with the proximal end at the site of the leak in 9 cases; in 1 case two stents were placed. The overall success rate of ERCP to manage the leak was 90%. There were no significant differences in age, gender, comorbidities, duration of symptoms, history of previous surgery or type of surgery performed between cases and controls. CONCLUSION: ERCP with stent placement is safe and effective for management of post-hepatectomy bile leak in patients with PLD. 展开更多
关键词 Polycystic liver HEPATECTOMY Bile leak Endoscopic retrograde cholangiopancreatography
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The Post-Merger Performance: Evidence From Italy
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作者 Fabrizio Rossi 《Chinese Business Review》 2012年第11期931-945,共15页
The objective of this paper is to investigate whether mergers create value for shareholders in both the short and long term. For this purpose, 120 announcements of mergers that were registered in Italy during the peri... The objective of this paper is to investigate whether mergers create value for shareholders in both the short and long term. For this purpose, 120 announcements of mergers that were registered in Italy during the period 1994-2006 among listed companies were examined. The short-term analysis was conducted using the event study methodology in order to estimate the cumulative abnormal returns (CARs) in the time window around the announcement date (-10, +10). In this work, the sample of 120 mergers was divided into two sub-samples: the first considers the mergers that were carried out in all sectors of the economy, and the second focuses only on bank mergers. From the results obtained it would appear that, while the sub-sample of all mergers registered a statistically significant value creation for the shareholders of both the bidder and target companies, values also confirmed by combined analysis, the second sub-sample registered negative values for bidder companies and positive values for target companies. Negative values also seem to be confirmed by the results of the combined analysis both at the date of announcement and throughout the entire period of observation. For the long-term analysis, the Buy and Hold Abnormal Returns (BHARs) methodology was used, with which it was possible to observe the returns for three years. In the 36 months following the merger, the portfolios showed a significant destruction of value 展开更多
关键词 post-merger performance Buy and Hold Abnormal Returns (BHARs) Cumulative Abnormal Returns(CARs) BANKS Italian stock market event study
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Research on service arrangement of taking senior citizens to hospital based on Customers' Satisfaction
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作者 Zheng Ran 《International English Education Research》 2015年第3期53-56,共4页
In the transportation service, customers' specially ordered time window is not always strictly obeyed and deviation of service time from customer-ordered time window determine customers' satisfaction degree, which c... In the transportation service, customers' specially ordered time window is not always strictly obeyed and deviation of service time from customer-ordered time window determine customers' satisfaction degree, which can be quantified by satisfactory function. And improved saving algorithm is proposed to solve the multi-objective model. A case study is also presented to verify effectiveness of the proposed algorithm. 展开更多
关键词 transportation service customers' satisfaction saving algorithm
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A Two-phase Solution Algorithm for the Inventory Routing Problem with Time Windows
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作者 Pantelis Z. Lappas Manolis N. Kritikos George D. Ioannou 《Journal of Mathematics and System Science》 2017年第9期237-247,共11页
The main objective of this paper is to propose a two-phase solution algorithm for solving the Inventory Routing Problem with Time Windows (IRPTW), which has not been excessively researched in the literature. The sol... The main objective of this paper is to propose a two-phase solution algorithm for solving the Inventory Routing Problem with Time Windows (IRPTW), which has not been excessively researched in the literature. The solution approach is based on (a) a simple simulation for the planning phase (Phase I) and (b) the Variable Neighborhood Search Algorithm (VNS) for the routing phase (Phase II). Testing instances are established to investigate algorithmic performance, and the computational results are then reported. The computational study underscores the importance of integrating the inventory and vehicle routing decisions. Graphical presentation formats are provided to convey meaningful insights into the problem. 展开更多
关键词 ROUTING Inventory Routing Problem with Time Windows Simple Simulation Variable Neighborhood Search
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A Statistical Analysis on Recent Tidal Triggering of the Earthquake in the Tianshan Seismic Zone
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作者 Li Jin Jiang Haikun +2 位作者 Qu Junhao Huang Yu Gao Chaojun 《Earthquake Research in China》 CSCD 2015年第2期203-213,共11页
A statistical analysis is done to study the spatio-temporai features of earthquake activity in the Tianshan seismic belt triggered by tide, based on Schuster's test. The data we choose is the ML ≥2. 0 earthquakes fr... A statistical analysis is done to study the spatio-temporai features of earthquake activity in the Tianshan seismic belt triggered by tide, based on Schuster's test. The data we choose is the ML ≥2. 0 earthquakes from January 1, 2010 to August 31, 2012 in eastern Tianshan, and the calculation is on tidal body stress. The results show that the p-value based on the time window smoothing of Schuster's test corresponds better with the strong earthquakes in the Tianshan seismic belt, especially for a long time before the November 1, 2011 Nilka Ms6. 0 earthquake, when the p-value of the Schuster's test was always lower than the threshold of 0. 05 for tidal trigger of earthquake, but after the Niika Ms6. 0 earthquake, that value was quickly restored to a high level, which reflects a close relationship between the Nilka Ms6. 0 earthquake and the Earth tide. According to the p-value based on the spatial window smoothing of Schuster's test, the Nilka Ms6. 0 earthquake was at or near the tidal triggering area. Thus we can see from the spatio-temporal results that the Nilka Ms6. 0 earthquake was obviously triggered by Earth fide. 展开更多
关键词 Tianshan seismic zone Nilka earthquake Tidal triggering Schuster's test
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Dynamic prediction of gas emission based on wavelet neural network toolbox 被引量:4
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作者 Yu-Min PAN Yong-Hong DENG Quan-Zhu ZHANG Peng-Qian XUE 《Journal of Coal Science & Engineering(China)》 2013年第2期174-181,共8页
This paper presents a method for dynamically predicting gas emission quantity based on the wavelet neural network (WNN) toolbox. Such a method is able to predict the gas emission quantity in adjacent subsequent time... This paper presents a method for dynamically predicting gas emission quantity based on the wavelet neural network (WNN) toolbox. Such a method is able to predict the gas emission quantity in adjacent subsequent time intervals through training the WNN with even time-interval samples. The method builds successive new model with the width of sliding window remaining invariable so as to obtain a dynamic prediction method for gas emission quantity. Furthermore, the method performs prediction by a self-developed WNN toolbox. Experiments indicate that such a model can overcome the deficiencies of the traditional static prediction model and can fully make use of the feature extraction capability of wavelet base function to reflect the geological feature of gas emission quantity dynamically. The method is characterized by simplicity, flexibility, small data scale, fast convergence rate and high prediction precision. In addition, the method is also characterized by certainty and repeatability of the predicted results. The effectiveness of this method is confirmed by simulation results. Therefore, this method will exert practical significance on promoting the application of WNN. 展开更多
关键词 dynamic prediction gas emission wavelet neural network TOOLBOX prediction model
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Time window characteristics of cultured rat hippocampal neurons subjected to ischemia and reperfusion 被引量:33
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作者 许忠 徐如祥 +4 位作者 刘宝松 姜晓丹 黄涛 丁涟沭 袁军 《Chinese Journal of Traumatology》 CAS 2005年第3期179-182,共4页
Objective: To explore cell death and apoptosis in rat hippocampal neurons at different time points after ischemia, hypoxia and reperfusion injury and to elucidate time window characteristics in ischemia neuronal injur... Objective: To explore cell death and apoptosis in rat hippocampal neurons at different time points after ischemia, hypoxia and reperfusion injury and to elucidate time window characteristics in ischemia neuronal injury. Methods: Hippocampal neurons were obtained from rat embryo and were cultured in vitro. The ischemia and reperfusion of cultured rat hippocampal neurons were simulated by oxygen-glucose deprivation (OGD) and recovery. OGD at different time points ((0.25) h to (3.0) h) and then the same recovery (24 h) were prepared. Annexin (V-PI) staining and flow cytometry examined neuron death and apoptosis at different time after injury. Results: After OGD and recovery, both necrosis and apoptosis were observed. At different times after OGD, there were statistically significant differences in neuron necrosis rate (P<(0.05)), but not in apoptosis rate (P>(0.05)). At recovery, survival rate of hippocampal neurons further decreased while apoptosis rate increased. Furthermore, apoptosis rates of different time differed greatly (P<(0.05)). Apoptosis rate gradually increased with significant difference among those of different time points (P<(0.05)). However, 2 h after ischemia, apoptosis rate decreased markedly. Conclusions: Apoptosis is an important pathway of delayed neuron death. The therapeutic time window should be within 2 h after cerebral ischemia and hypoxia. 展开更多
关键词 Hypoxia-ischemia brain Reperfusion injury HIPPOCAMPUS NEURONS Time window
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Hybrid planning for LEO long-duration multi-spacecraft rendezvous mission 被引量:9
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作者 ZHANG Jin LUO YaZhong TANG GuoJin 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第1期233-243,共11页
For the low-earth-orbit (LEO) long-duration multi-spacecraft rendezvous mission, a mixed integer nonlinear programming (MINLP) model is built with consideration of the , perturbation and the time window constraint... For the low-earth-orbit (LEO) long-duration multi-spacecraft rendezvous mission, a mixed integer nonlinear programming (MINLP) model is built with consideration of the , perturbation and the time window constraints based on lighting condition. A two-level hybrid optimization approach is proposed. The up-level problem uses the visiting sequence, the orbital transfer duration and the service time after each rendezvous as design variables, and employs the mix-coded genetic algorithm to search the optimal solution; the low-level problem uses the maneuver time and impulses in each rendezvous as design vari- ables, and employs the downhill simplex method to search the optimal solution. To improve the solving efficiency of the low-level problem, a linear dynamic model with J~ perturbation is derived, and the approximate strategy of the low-level prob- lem is then proposed. The proposed method has been applied to several numerical problems. The results lead to three major conclusions: (1) The MINLP model for LEO long-duration multi-spacecraft rendezvous mission is effective, and the proposed hybrid optimization strategy can obtain good solutions that satisfy time window constraints; (2) The derived linear dynamic equations are good first-order approximation to the long-duration rendezvous trajectory under ,J2 perturbation; (3) Under J2 perturbation, the long-duration rendezvous problem has multiple local minimums either in the duration of multiple orbits or in a single orbit, and it agrees with the problem's characteristic to use the mix-coded genetic algorithm. 展开更多
关键词 multi-spacecraft rendezvous long-duration rendezvous hybrid planning rendezvous time window lighting constraints J2 perturbation
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Stable tin perovskite solar cells enabled by widening the time window for crystallization 被引量:2
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作者 Zhensheng Dai Wentao Tang +9 位作者 Tao Wang Taoyuze Lv Xinhui Luo Danyu Cui Ruitian Sun Liang Qiao Han Chen Rongkun Zheng Xudong Yang Liyuan Han 《Science China Materials》 SCIE EI CAS CSCD 2021年第8期1849-1857,共9页
Tin perovskite solar cells (TPSCs) are the most promising candidates for lead-free perovskite solar cells(PSCs).However,the poor crystallization and chemical stability of Sn perovskites are the two challenging issues ... Tin perovskite solar cells (TPSCs) are the most promising candidates for lead-free perovskite solar cells(PSCs).However,the poor crystallization and chemical stability of Sn perovskites are the two challenging issues for further application of TPSCs.Here,we present a strategy to stabilize CH(NH_(2))2SnI3(FASnI3) perovskite enabled by an amine complex,CH3NH3I·3CH3NH_(2),which can hinder the major degradation issue caused by the oxidation of Sn2+to Sn4+.The resulting Sn perovskite films exhibit enhanced crystallinity and stability in comparison with those made with conventional inorganic SnF2 additives.Finally,the device achieved a higher external quantum efficiency for charge extraction and a power conversion efficiency (PCE) of 9.53%,which maintained more than 90%of the initial efficiency after1000 h of light soaking under the standard AM 1.5 G solar illumination. 展开更多
关键词 lead-free perovskite FASnI3 perovskite solar cells CRYSTALLIZATION stability
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Wavelet Variance Analysis of EEG Based on Window Function 被引量:3
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作者 ZHENG Yuan-zhuang YOU Rong-yi 《Chinese Journal of Biomedical Engineering(English Edition)》 2014年第2期54-59,共6页
A new wavelet variance analysis method based on window function is proposed to investigate the dynamical features of electroencephalogram(EEG).The exprienmental results show that the wavelet energy of epileptic EEGs a... A new wavelet variance analysis method based on window function is proposed to investigate the dynamical features of electroencephalogram(EEG).The exprienmental results show that the wavelet energy of epileptic EEGs are more discrete than normal EEGs, and the variation of wavelet variance is different between epileptic and normal EEGs with the increase of time-window width. Furthermore, it is found that the wavelet subband entropy (WSE) of the epileptic EEGs are lower than the normal EEGs. 展开更多
关键词 wavelet variance EEG wavelet subband entropy (WSE) window function
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