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基于Multi-Agent的水电站变压器故障诊断系统
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作者 乔丹 马鹏 王琦 《自动化技术与应用》 2024年第7期58-61,65,共5页
为了精准、快速完成水电站变压器的故障诊断,设计基于Multi-Agent的水电站变压器故障诊断系统。变压器状态监控agent将检测到的变压器故障信息发送给系统管理agent,系统管理agent通过通信agent将变压器故障信息发送给变压器故障诊断age... 为了精准、快速完成水电站变压器的故障诊断,设计基于Multi-Agent的水电站变压器故障诊断系统。变压器状态监控agent将检测到的变压器故障信息发送给系统管理agent,系统管理agent通过通信agent将变压器故障信息发送给变压器故障诊断agent,变压器故障诊断agent利用小波变换方法提取变压器故障特征,并将其作为IFOA-SVM模型输入,完成变压器故障分类后,获取变压器故障诊断结果,该结果通过通信agent显示给用户。实验表明,该系统可有效诊断变压器故障诊断,诊断成功率受系统故障信息丢失率的影响较小,诊断耗时、耗能小,并具有较高故障诊断成功率。 展开更多
关键词 multi-AGENT 水电站 变压器 故障诊断 小波变换
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Location of Electric Vehicle Charging Station Based on Spatial Clustering and Multi-hierarchical Fuzzy Evaluation 被引量:2
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作者 Wang Meng Liu Kai 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第1期89-96,共8页
For the charging station construction of electric vehicle,location selecting is a key issue.There are two problems in location selection of the electric vehicle charging station.One is determining the location of char... For the charging station construction of electric vehicle,location selecting is a key issue.There are two problems in location selection of the electric vehicle charging station.One is determining the location of charging station;the other is evaluating the location of charging station.To determine the charging station location,an spatial clustering algorithm is proposed and programmed.The example simulation shows the effectiveness of the spatial clustering algorithm.To evaluate the charging station location,a multi-hierarchical fuzzy method is proposed.Based on the location factors of electric vehicle charging station,the hierarchical evaluation structure of electric vehicle charging station location is constructed,including three levels,4first-class factors and 14second-class factors.The fuzzy multi-hierarchical evaluation model and algorithm are built.The analysis results show that the multi-hierarchical fuzzy method can reasonably complete the electric vehicle charging station location evaluation. 展开更多
关键词 electric vehicle CHARGING station spatial CLUSTERING multi-hierarchical fuzzy evaluation
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Synthesized Multi-station Tribo-test System for Bio-tribological Evaluation in Vitro
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作者 WU Tonghai DU Ying +2 位作者 LI Yang WANG Shuo ZHANG Zhinan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第4期853-861,共9页
Tribological tests play an important role on the evaluation of long-term bio-tribological performances of prosthetic materials for commercial fabrication.Those tests focus on the motion simulation of a real joint in v... Tribological tests play an important role on the evaluation of long-term bio-tribological performances of prosthetic materials for commercial fabrication.Those tests focus on the motion simulation of a real joint in vitro with only normal loads and constant velocities,which are far from the real friction behavior of human joints characterized with variable loads and multiple directions.In order to accurately obtain the bio-tribological performances of artificial joint materials,a tribological tester with a miniature four-station tribological system is proposed with four distinctive features.Firstly,comparability and repeatability of a test are ensured by four equal stations of the tester.Secondly,cross-linked scratch between tribo-pairs of human joints can be simulated by using a gear-rack meshing mechanism to produce composite motions.With this mechanism,the friction tracks can be designed by varying reciprocating and rotating speeds.Thirdly,variable loading system is realized by using a ball-screw mechanism driven by a stepper motor,by which loads under different gaits during walking are simulated.Fourthly,dynamic friction force and normal load can be measured simultaneously.The verifications of the performances of the developed tester show that the variable frictional tracks can produce different wear debris compared with one-directional tracks,and the accuracy of loading and friction force is within ?5%.Thus the high consistency among different stations can be obtained.Practically,the proposed tester system could provide more comprehensive and accurate bio-tribological evaluations for prosthetic materials. 展开更多
关键词 artificial joint multi-station tribological tester bio-tribology testing system
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Distributed power allocation over indoor multi-pico stations
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作者 费泽松 高强 +2 位作者 傅友 Tero Isotalo Jarno Niemela 《Journal of Beijing Institute of Technology》 EI CAS 2015年第2期227-232,共6页
A low-complexity distributed power allocation algorithm is proposed to reduce the interference and improve the transmitting rate of edge users. Different scenarios are considered and user experience of indoor communic... A low-complexity distributed power allocation algorithm is proposed to reduce the interference and improve the transmitting rate of edge users. Different scenarios are considered and user experience of indoor communication is promoted. The simulation results prove the effectiveness of our algorithm. The proposed power control scheme ensures that more users can achieve their required rate and the fairness of different users is improved. Besides, more than 5096 energy can be saved without loss in outage ability, and energy efficiency is also promoted. In addition, the proposed algorithm can be extended to scenarios that the required rates of pico stations can be changed periodically. 展开更多
关键词 distributed power allocation indoor communication multi-pico stations
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Controllers Design for the Multi-Shuttle and Multi-Station Transportation System
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作者 Tien Dong Ha Minh Tien Trinh +1 位作者 Tran Thanh Cong Vu Tuong Quan Vo 《Open Journal of Applied Sciences》 2021年第8期946-965,共20页
Nowadays, the Multi-Shuttle and Multi-Station Transportation System (MMTS)<span><span><span style="font-family:;" "=""> is one of the most interesting research topics in many... Nowadays, the Multi-Shuttle and Multi-Station Transportation System (MMTS)<span><span><span style="font-family:;" "=""> is one of the most interesting research topics in many fields of industries. It is an effective solution to reduce unexpected accidents that occur during transportation as well as increase productivity in manufacturing. The aim of this paper is to introduce the controller design for the MMTS which is built in our BK-Recme BioMech Lab at Ho Chi Minh City University of Technology (VNU-HCM), Viet Nam. Based on the design of this system, the control algorithms will be conducted to check the operation of the whole system. To evaluate the feasibility and effectiveness of this model, we design a series of random instances for different quantities of nodes as well as the different quantities of shuttles. Our system includes 4 stations and 6 shuttles which are assembled in the serial chain system. However, the number of stations and number of shuttles can be expanded to any desired ones which are based on the requirement of the industries. In this paper, we mainly focus on the controller design of this system to make it operate in an effective way that the goods will be transported and delivered to the target station as fast as possible. In order to solve the large</span></span></span><span><span><span style="font-family:;" "="">-</span></span></span><span><span><span style="font-family:;" "="">scale instances and realistic transport prob<span>lems, we propose three algorithms for three progresses as shuttles calling</span>, path reading and shuttles communicating. The shuttles calling is to decide which <span>shuttle should be called to the star</span></span></span></span><span><span><span style="font-family:;" "="">t</span></span></span><span><span><span style="font-family:;" "="">-node. Path reading to determine the shortest</span></span></span><span><span><span style="font-family:;" "=""> <span>way to go from start-node to end-node. Finally, shuttles communicating,</span> which allow one shuttle to interact with the next shuttles so we have a loop of orders (shuttle 1 to shuttle 2;shuttle 2 to shuttle 3;etc</span></span></span><span><span><span style="font-family:;" "="">.</span></span></span><span><span><span style="font-family:;" "="">;shuttle n-1 to shuttle n). This proposes solution can help us to solve the huge numbers of shuttles <span>and stations in the system. The specific result of this study is applying</span> Dijkstra’s algorithm to propose an algorithm that allows handling a transportation system without caring about the number of shuttles as well as the number of stations for the closed-loop path. Several test problems are carried out in order to check the feasibility and the effectiveness of our purposed control algorithm.</span></span></span> 展开更多
关键词 multi-station multi-Shuttle Transportation SHUTTLE CALLING RFID COMMUNICATING Start-Node End-Node
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计及深度调峰的风-光-水-火-抽蓄多能源联网系统优化调度研究 被引量:2
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作者 李卫国 丁硕 +1 位作者 安祎宁 蔡婷婷 《东北电力大学学报》 2024年第3期83-93,共11页
多种能源联网运行逐步成为未来电力系统发展的方向,多能源联网系统的优化调度是应对规模化新能源并网消纳的重要手段。文中建立了计及火电机组深度调峰成本的风-光-水-火-抽蓄联网系统成本模型和考虑调峰主动性的风-光-水-火-抽蓄联网... 多种能源联网运行逐步成为未来电力系统发展的方向,多能源联网系统的优化调度是应对规模化新能源并网消纳的重要手段。文中建立了计及火电机组深度调峰成本的风-光-水-火-抽蓄联网系统成本模型和考虑调峰主动性的风-光-水-火-抽蓄联网系统日前优化调度模型。针对多能源耦合系统结构复杂的情况,提出了分层优化调度的模型求解策略。上层模型以净负荷波动最小为优化目标,得到等效负荷曲线;下层模型根据上层模型的调度结果,以调峰运行的经济性最优和新能源弃电率最低为目标函数,计及调峰主动性,求解考虑火电机组深度调峰煤耗特性的含新能源系统的经济调度问题。仿真算例表明所建模型实现了多能源联网系统的互补运行,提升了火电机组的深度调峰能力,降低新能源弃电率和系统运行成本。 展开更多
关键词 多能源系统 抽水蓄能电站 深度调峰 优化调度 调峰主动性
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Multi-features Based Approach for Moving Shadow Detection 被引量:4
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作者 周宁 周曼丽 +1 位作者 许毅平 方宝红 《Journal of Donghua University(English Edition)》 EI CAS 2004年第6期76-80,共5页
In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving... In the video-based surveillance application, moving shadows can affect the correct localization and detection of moving objects. This paper aims to present a method for shadow detection and suppression used for moving visual object detection. The major novelty of the shadow suppression is the integration of several features including photometric invariant color feature, motion edge feature, and spatial feature etc. By modifying process for false shadow detected, the averaging detection rate of moving object reaches above 90% in the test of Hall-Monitor sequence. 展开更多
关键词 MOVING SHADOW detection multi - features MOVING OBJECT DETECTION
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The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) 被引量:43
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作者 Xiang-Qun Cui Yong-Heng Zhao +52 位作者 Yao-Quan Chu Guo-Ping Li Qi Li Li-Ping Zhang Hong-Jun Su Zheng-Qiu Yao Ya-Nan Wang Xiao-Zheng Xing Xin-Nan Li Yong-Tian Zhu Gang Wang Bo-Zhong Gu A-Li Luo Xin-Qi Xu Zhen-Chao Zhang Gen-Rong Liu Hao-Tong Zhang De-Hua Yang Shu-Yun Cao Hai-Yuan Chen Jian-Jun Chen Kun-Xin Chen Ying Chen Jia-Ru Chu Lei Feng Xue-Fei Gong Yong-Hui Hou Hong-Zhuan Hu Ning-Sheng Hu Zhong-Wen Hu Lei Jia Fang-Hua Jiang Xiang Jiang Zi-Bo Jiang Ge Jin Ai-Hua Li Yan Li Ye-Ping Li Guan-QunLiu Zhi-Gang Liu Huo-Ming Shi Zheng-Hong Tang Qing-Sheng Tao Xiang-Yan Yuan Chao Zhai Jing Zhang Yan-Xia Zhang Yong Zhang Ming Zhao Fang Zhou Guo-Hua Zhou Jie Zhu Si-Cheng Zou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2012年第9期1197-1242,共46页
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti... The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects. 展开更多
关键词 techniques: wide field telescope - active optics - multi fiber - spectroscopy survey - data reduction
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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block 被引量:2
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作者 朱参战 崔长琮 +5 位作者 张全发 薛小临 刘维维 刘引会 《South China Journal of Cardiology》 CAS 2001年第2期101-105,共5页
Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS ... Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function. 展开更多
关键词 multi - site cardiac pacingHemodynamics
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Research on A Master - slave Multi - microcomputers Control System for Hollow Spindle Fancy Yarn Spinning Machine
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作者 李志蜂 陈子展 阵瑞琪 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期49-52,共4页
In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardwar... In this paper, a successfully studied and developed master - slave muld - microcomputers control system based on PC - BUS for hollow spindle fancy yarn spinning machine, mainly Its overall scheme, software and hardware construction, is introduced. Spinning experiments show that the system achieves satisfactory result. This system can solve the diftkultles of mechatronical fusion between domestic hollow splndk fancy yarn spuming muchine and its microcomputer control technology. 展开更多
关键词 hollow SPINDLE FANCY YAM spinning machine mechatrvnical fusion MASTER - SLAVE multi - microcomputers control system PC - BUS.
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On the Representation of Multi-layer Woven Structure
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作者 易洪雷 丁辛 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期14-16,共3页
A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the rein... A quantitative method is developed to identify the structures of multi-layer woven fabric in this study. Six structural parameters are selected to represent the fabric structure. With some design criteria for the reinforcement of textile composites, the relationships among the structural parameters are derived for different binding patterns of the fabric structure. The conditions, which meet the requirements of structural cell stability,are also discussed. 展开更多
关键词 multi - layer woven FABRIC structural parame-ter BINDING PATTERN TEXTILE composite .
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Computer-aided Pattern Design of Multi-bar Warp Knitted Fabrics
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作者 李炜 《Journal of China Textile University(English Edition)》 EI CAS 2000年第1期85-87,共3页
To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the ... To meet the development trend of multi-bar warp knit-ting machine towards high-speed,advanced technologyand computer control and the requirements of variousproducts with small quantity,there are many researcheson the computer-aided pattern design of multi-barwarp knitted fabrics.In terms of the special propertiesof the computer-aided pattern design of multi-barwarp knitted fabrics,the Object Oriented Program(OOP)programming-Object Windows class Library(OWL)programming is selected.According to thecharacters of the OWL programming,various functionsare defined.Pattern design and technical parameters canbe output,which offers a great convenience for the fac-tory. 展开更多
关键词 multi - bar WARP KNITTED fabric computer -aided PATTERN design PATTERN Object Windows class Library (OWL) programming.
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基于改进NSGA-Ⅱ算法的梯级水电站多目标调度方法
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作者 陈文 孙波 +1 位作者 张博 李向阳 《水电能源科学》 北大核心 2024年第8期182-186,154,共6页
近年来区域暴雨洪涝灾害的突发性、极端性、反常性显著增强,年内径流时空分布不均匀性进一步加剧,在梯级水电站汛期调度中均衡防洪与兴利任务成为重要研究课题。针对梯级水电站多目标联合调度问题,提出了一种基于NSGA-Ⅱ算法的求解方法... 近年来区域暴雨洪涝灾害的突发性、极端性、反常性显著增强,年内径流时空分布不均匀性进一步加剧,在梯级水电站汛期调度中均衡防洪与兴利任务成为重要研究课题。针对梯级水电站多目标联合调度问题,提出了一种基于NSGA-Ⅱ算法的求解方法,该方法改进了NSGA-Ⅱ算法的种群生成策略及精英选择策略,以梯级各电站时段平均防洪库容占用率作为防洪风险函数、梯级年发电量作为兴利目标函数,结合Pareto前沿分析方法求解了含防洪、兴利目标函数的梯级水电站联合调度问题。最后,以某流域梯级水电站多年平均来水条件下梯级联合调度为例对模型算法进行了验证分析。结果表明,基于改进NSGA-Ⅱ算法的梯级水电站多目标调度方法可以满足梯级水电站汛期防洪调度要求,同时梯级年发电量较常规调度图调度方式年发电量增加2.7%,更好地发挥了梯级水电站的综合效益。 展开更多
关键词 NSGA-Ⅱ算法 梯级水电站 多目标优化 发电调度
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A Review in the Core Technologies of 5G: Device-to-Device Communication, Multi-Access Edge Computing and Network Function Virtualization 被引量:2
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作者 Ruixuan Tu Ruxun Xiang +1 位作者 Yang Xu Yihan Mei 《International Journal of Communications, Network and System Sciences》 2019年第9期125-150,共26页
5G is a new generation of mobile networking that aims to achieve unparalleled speed and performance. To accomplish this, three technologies, Device-to-Device communication (D2D), multi-access edge computing (MEC) and ... 5G is a new generation of mobile networking that aims to achieve unparalleled speed and performance. To accomplish this, three technologies, Device-to-Device communication (D2D), multi-access edge computing (MEC) and network function virtualization (NFV) with ClickOS, have been a significant part of 5G, and this paper mainly discusses them. D2D enables direct communication between devices without the relay of base station. In 5G, a two-tier cellular network composed of traditional cellular network system and D2D is an efficient method for realizing high-speed communication. MEC unloads work from end devices and clouds platforms to widespread nodes, and connects the nodes together with outside devices and third-party providers, in order to diminish the overloading effect on any device caused by enormous applications and improve users’ quality of experience (QoE). There is also a NFV method in order to fulfill the 5G requirements. In this part, an optimized virtual machine for middle-boxes named ClickOS is introduced, and it is evaluated in several aspects. Some middle boxes are being implemented in the ClickOS and proved to have outstanding performances. 展开更多
关键词 5th Generation Network VIRTUALIZATION Device-To-Device COMMUNICATION Base station Direct COMMUNICATION INTERFERENCE multi-Access EDGE COMPUTING Mobile EDGE COMPUTING
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MODS: A Novel Metaheuristic of Deterministic Swapping for the Multi-Objective Optimization of Combinatorials Problems
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作者 Elias David Nifio Ruiz Carlos Julio Ardila Hemandez +2 位作者 Daladier Jabba Molinares Agustin Barrios Sarmiento Yezid Donoso Meisel 《Computer Technology and Application》 2011年第4期280-292,共13页
This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Auto... This paper states a new metaheuristic based on Deterministic Finite Automata (DFA) for the multi - objective optimization of combinatorial problems. First, a new DFA named Multi - Objective Deterministic Finite Automata (MDFA) is defined. MDFA allows the representation of the feasible solutions space of combinatorial problems. Second, it is defined and implemented a metaheuritic based on MDFA theory. It is named Metaheuristic of Deterministic Swapping (MODS). MODS is a local search strategy that works using a MDFA. Due to this, MODS never take into account unfeasible solutions. Hence, it is not necessary to verify the problem constraints for a new solution found. Lastly, MODS is tested using well know instances of the Bi-Objective Traveling Salesman Problem (TSP) from TSPLIB. Its results were compared with eight Ant Colony inspired algorithms and two Genetic algorithms taken from the specialized literature. The comparison was made using metrics such as Spacing, Generational Distance, Inverse Generational Distance and No-Dominated Generation Vectors. In every case, the MODS results on the metrics were always better and in some of those cases, the superiority was 100%. 展开更多
关键词 METAHEURISTIC deterministic finite automata combinatorial problem multi - objective optimization metrics.
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Variations in the Atmospheric Electric Field at Tropical Station during 1930-1987
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作者 S. S. Kandalgaonkar G. K. Manohar 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1991年第1期99-106,共8页
The variations noticed in the atmospheric electric field recorded at Pune (18°32'N, 73°51'E, 559 m ASL), a tropical inland station located in Dcccan Plateau, India, during the period 1930-1987, have ... The variations noticed in the atmospheric electric field recorded at Pune (18°32'N, 73°51'E, 559 m ASL), a tropical inland station located in Dcccan Plateau, India, during the period 1930-1987, have been examined in relation to the variations observed in the Angstrom turbidity coefficient (β) and selected meteorological parameters. The monthly and annual mean values of the atmospheric electric field. Angstrom turbidity coefficient (β), rainfall, temperature and relative humidity for the years 1930-1938, 1957-1958, 1964-1965, 1973-1974 and 1987 were considered in the study.The results of the above study indicated gradual increases in the atmospheric electric field over the period of study (1930-1987) which is statistically significant at less than 5%level. The increases noticed during different periods varied from 30 to 109%. The increase noticed during the period (1930-1938) and (1973-1974) was maximum (109%). The Angstrom turbidity coefficient also showed systematic increases during the period of study, which is consistent. The diurnal curve of the atmospheric electric field at the station by and large, showed a double oscillation, which is generally observed in the conlinental environments. 展开更多
关键词 Variations in the Atmospheric Electric Field at Tropical station during 1930-1987
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多层界面的H-κ扫描方法获取的拉萨深部结构特征
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作者 吴蔚 牛潇 +2 位作者 贺日政 李宗旭 唐利民 《地震学报》 CSCD 北大核心 2024年第5期787-805,共19页
对不同深度莫霍面正演模拟的每条接收函数进行H-κ扫描,将得到的H和κ投影到平面图,发现同深度莫霍面的投影点能够拟合成一条曲线,进而通过该曲线能够分离不同深度界面对应的接收函数。在此基础上,再利用H-κ-θ方法计算估计倾斜界面的... 对不同深度莫霍面正演模拟的每条接收函数进行H-κ扫描,将得到的H和κ投影到平面图,发现同深度莫霍面的投影点能够拟合成一条曲线,进而通过该曲线能够分离不同深度界面对应的接收函数。在此基础上,再利用H-κ-θ方法计算估计倾斜界面的倾角和倾向。最终实现倾斜界面和“双莫霍”现象的辨识。利用此流程处理了拉萨固定台站(LSA)记录的大量接收函数,获得了拉萨台下方的地壳厚度约为70 km,地壳平均波速比约为1.67,莫霍面倾向北东,倾角为24°,而莫霍面下俯冲的印度板块界面深度约为106 km,倾向正北,倾角约为40°,其上方地幔楔内部的平均波速比约为1.69。正演模型计算结果和实际观测数据检验综合表明该方法能较好地区分不同界面对应的接收函数,藉此获取其界面的构造变化特征,有助于获得更加精细的壳幔结构特征。 展开更多
关键词 接收函数 多层界面 倾斜界面 拉萨地震台
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基于NSGA-Ⅲ算法的长距离调水泵站多目标优化调度研究
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作者 王永康 吕谋 +1 位作者 李源 冯鹏 《水电能源科学》 北大核心 2024年第5期154-158,共5页
针对长距离调水泵站运行过程中水泵运行效率低、安全隐患较大等问题,以调水泵站运行电费最小、水泵平均效率最大、水泵流量平均偏离度最小、水泵平均启停频次最小为目标建立优化模型。以华东某沿海城市调水工程为例,采用第三代非支配排... 针对长距离调水泵站运行过程中水泵运行效率低、安全隐患较大等问题,以调水泵站运行电费最小、水泵平均效率最大、水泵流量平均偏离度最小、水泵平均启停频次最小为目标建立优化模型。以华东某沿海城市调水工程为例,采用第三代非支配排序遗传算法(NSGA-Ⅲ)求解优化模型,运用层次分析法与CRITIC法进行组合赋权,结合逼近理想解排序法(TOPSIS)进行方案优选。结果表明,相较于常规调度方案,优化调度方案中两泵站的运行电费和水泵流量平均偏离度均显著降低,水泵平均效率均显著提高,水泵平均启停频次均有所减少。表明在综合考虑泵站运行经济性的情况下,所建优化模型能够有效降低安全隐患。 展开更多
关键词 长距离调水泵站 NSGA-Ⅲ算法 多目标优化 多属性决策 优化调度
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基于多头自注意力机制的LSTM-TCN基站流量预测算法
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作者 李维烨 贾海蓉 +1 位作者 申陈宁 吴永强 《现代电子技术》 北大核心 2024年第23期125-130,共6页
基站流量预测对于蜂窝网络的规划、资源分配和用户体验优化至关重要。为提高基站流量预测精度,文中设计一种结合多头自注意机制(MHSA)的LSTM-TCN基站流量预测算法。其中:MHSA能够从多个角度强化基站流量数据的内在关联,增强了模型对流... 基站流量预测对于蜂窝网络的规划、资源分配和用户体验优化至关重要。为提高基站流量预测精度,文中设计一种结合多头自注意机制(MHSA)的LSTM-TCN基站流量预测算法。其中:MHSA能够从多个角度强化基站流量数据的内在关联,增强了模型对流量数据重要特征的表达能力;LSTM-TCN模型中长短期记忆(LSTM)网络捕捉流量数据中的长短时依赖性;时间卷积网络(TCN)进一步捕捉流量数据中的全局特征,使得模型能够提取基站流量数据在不同时间尺度上的变化模式和时间依赖关系,提高基站流量预测模型的拟合能力和预测精度。实验结果表明,该流量预测算法与其他算法相比,在运营商基站流量数据的预测中有效降低了均方根误差和平均绝对误差,提高了决定系数,验证了该流量预测算法的有效性,从而为基站休眠节能提供决策支持。 展开更多
关键词 5G流量 基站 流量预测 混合神经网络 多头自注意 LSTM-TCN
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MEDIUM-RANGE OSCILLATION OF METEOROLOGICAL ELEMENTS AT GREAT WALL STATION,ANTARCTICA
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作者 Lu Longhua Bian Lingen Zhang Yongping Polar Meteorological Laboratory, Academy of Meteorological Sciences, Beijing 100081 《Chinese Journal of Polar Science》 1990年第1期36-48,共13页
A method of multi-spectral analysis is used to study the spectral characteristics of surface and upper-level meteorological elements over the Great Wall Station (62°12'S, 58°57'W), Antarctica and the... A method of multi-spectral analysis is used to study the spectral characteristics of surface and upper-level meteorological elements over the Great Wall Station (62°12'S, 58°57'W), Antarctica and their phasecorrelation, propagation of mean oscillation at 500hPa level in the Southern Hemisphere and their corresponding synoptic sense. the results are summed up as follows: 1. Over the sub-Antatctic zone, as in the Northern Hemisphere there generally exist quasi-weekly oscillation and quasi-biweekly oscillation. In different seasons the oscillations of meteorological elements are different: in winter season quasi-biweekly oscillation is dominant, while in summer season quasi-weekly oscillation is dominant. 2. From the Earth's surface to the lower stratosphere there is a distinct quasi-weekly oscillation at each isobaric surface, but the most intense oscillation appears at 200-300hPa, and the oscillations of height and temperature are propagated downward. 3. Both in winter and summer seasons the quasi-biweekly oscillation are propagated from west to east, and the mean velocity of its propagation is about 7-17 longtitude / day. 4. The quasi-biweekly oscillation and the quasi-weekly oscillation over the sub - Antarctic zone are closely related to the activity and intensity variation of polar vortex at 500hPa, while at 1000hPa they reflect an interaction between the circumpolar depression and the sub-tropical high. The quasi-biweekly oscillation may be a reflection of inherent oscillation of the polar vortex, where as the quasi-weekly oscillation is a result of forced oscillation by external disturbance.A large number of calculations and analysis made reveals the features of medium-range oscillation over the sub-Antarctic zone. The results are of significance for understanding the behaviour of synoptic dynamics and making the weather forecast.This work is supported by National Committee for Antarctic Research. 展开更多
关键词 Antarctic Great Wall station Meteorological elements multi-spectral analysis method Medium-range oscillation Polar vortex.
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