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Using Stochastic Colored Petri nets for Designing Multi-Purpose Plants 被引量:2
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作者 Hasan Hosseini-Nasab Ali Sadri 《Engineering(科研)》 2012年第10期655-661,共7页
Designing of a multi-purpose plant as one of the well-known manufacturing systems is more challenging than other manufacturing systems. This paper applies a stochastic colored Petri net (CPN) to design and analyze mul... Designing of a multi-purpose plant as one of the well-known manufacturing systems is more challenging than other manufacturing systems. This paper applies a stochastic colored Petri net (CPN) to design and analyze multi-purpose plants. A simple approach is proposed to determine the utilization of shared resources and to reduce the equipment’s idle times. Three scenarios are presented to describe the proposed model. Generally, according to desire of a decision maker, different scenarios can be considered in the model to achieve to the expected design or plant configuration. The main characteristics of the proposed model are flexibility, the easiness of practical application and the simulation of the model in an easy way. 展开更多
关键词 multi-purpose Plant STOCHASTIC COLORED PETRI Net Simulation
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Water Quality Assessment of the Owena Multi-Purpose Dam, Ondo State, Southwestern Nigeria 被引量:1
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作者 Oyhakilome Gloria Irenosen Aiyesanmi Ademola Festus Akharaiyi Fred Coolborn 《Journal of Environmental Protection》 2012年第1期14-25,共12页
Composite water samples taken from Owena Multi-purpose Dam in six sampling campaigns covering the wet and dry seasons were analyzed for physico-chemical and microbial characteristics using standard methods for the exa... Composite water samples taken from Owena Multi-purpose Dam in six sampling campaigns covering the wet and dry seasons were analyzed for physico-chemical and microbial characteristics using standard methods for the examination of water and wastewater jointly published by the American Public Health Association, American Water Works Association and Water Pollution Control Federation. Results showed significant (p < 0.05) seasonal variations in most measured parameters with few showing significant spatial variation. The characteristics of the water from the dam lake revealed an acceptable quality for most measured parameters with low chemical pollutants burden when compared with drinking water standards and water quality for aquaculture. However, high values of turbidity, colour, iron, manganese and microbial load were recorded compared with drinking water standards, which call for proper treatment of the water before distribution for public consumption. 展开更多
关键词 Water PHYSICOCHEMICAL Characteristics MICROBIOLOGY Heavy Metals Owena multi-purpose DAM
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Design and Implementation of Training Simulator for Multi-purpose Construction Crawler
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作者 李文鸿 孙劭文 +2 位作者 张琦 孙伟 史本广 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第4期316-320,共5页
An efficient multi-purpose construction crawler training simulator is developed based on windows platform using digital signal processing,multimedia,sensing,simulation modeling and real-time visualization simulation t... An efficient multi-purpose construction crawler training simulator is developed based on windows platform using digital signal processing,multimedia,sensing,simulation modeling and real-time visualization simulation technologies. The simulator architecture and each part are discussed in this paper. The module designs for data acquisition,dynamic modeling and visual,sound and assess simulation are focused. The system has been put into practice and the satisfactory results are got. 展开更多
关键词 计算机仿真 模拟 技术 系统仿真
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Kill probability modeling of multi-purpose guided missile against gunship and its application
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作者 DU Zheng CHEN Wan-chun 《Journal of Measurement Science and Instrumentation》 CAS 2014年第2期9-18,共10页
针对多用途导弹对武装直升机单发杀伤概率建模中存在的问题,本文提出了直升机旋翼桨叶易损单元重要性因子的概念,并综合运用蒙特卡罗方法和运动学原理采用新思路建立旋翼激光引信启动模型和战斗部对旋翼桨叶条件杀伤概率模型。根据有限... 针对多用途导弹对武装直升机单发杀伤概率建模中存在的问题,本文提出了直升机旋翼桨叶易损单元重要性因子的概念,并综合运用蒙特卡罗方法和运动学原理采用新思路建立旋翼激光引信启动模型和战斗部对旋翼桨叶条件杀伤概率模型。根据有限的数据对武装直升机装甲厚度进行优化估算并通过实验进行验证,最终建立了多用途导弹对武装直升机完整的单发杀伤概率数学模型,为准确客观地分析多用途导弹对武装直升机目标的杀伤概率提供了必要的数学工具。基于所建立的单发杀伤概率模型,对影响多用途导弹杀伤概率的主要因素进行灵敏度分析及优化设计,分析及优化结果明显改善了单枚多用途导弹对武装直升机的杀伤性能。 展开更多
关键词 多用途导弹 武装直升机 旋翼桨叶 桨叶重要性因子 装甲厚度 杀伤概率
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Implementation and Evaluation of Dual-Purpose Normal and Disaster Situations System Based on Delay and Disruption Tolerant Bluetooth MANETs
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作者 Yuya Minami Yuya Kitaura +4 位作者 Yuri Tsutsui Eitaro Kohno Shinji Inoue Tomoyuki Ohta Yoshiaki Kakuda 《International Journal of Communications, Network and System Sciences》 2015年第9期342-357,共16页
Dual-purpose systems for both normal and disaster situations are necessary for providing continuous services from normal situations to disaster situations. We have been developing the dual-purposed systems based on th... Dual-purpose systems for both normal and disaster situations are necessary for providing continuous services from normal situations to disaster situations. We have been developing the dual-purposed systems based on the assurance network design principle. The assurance network design principle makes the dual-purpose systems work stably in both normal and disaster situations. This paper proposes a connectivity-dependent data propagation scheme, in which each terminal transfers data adaptively by wireless multi-hop data transfer or store-and-forward data transfer depending on whether the terminal has connections to its neighboring terminals. To verify the resilience against disconnection among neighboring terminals, we show field experimental results on data propagation time. Also we propose the dual-purpose system, in which there are two types of graphical user interface (GUI) for both situations. Whenever each terminal receives a special packet in disaster situations, the GUI automatically switches from one type for normal situations to another type for disaster situations. We have unified these two types of GUI so that users can understand how to use them even when GUI is automatically switched. To validate feasibility of the dual-purpose normal and disaster situations system, we show experimental results on dissemination of assessment information and automatical switching of GUIs. 展开更多
关键词 Android BLUETOOTH MANET GUI Dual-purpose SYSTEM DATA Propagation Wireless multi-Hop DATA Transfer Epidemic Routing
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低水头大型水利枢纽汛期运行水位动态控制方法研究与应用--以长洲水利枢纽为例 被引量:1
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作者 赵璧奎 邱静 +2 位作者 黄本胜 谭超 刘达 《水利学报》 EI CSCD 北大核心 2023年第5期530-540,共11页
水库汛期运行水位动态控制是促进雨洪资源利用、缓解水库防洪与兴利之间矛盾、提高水电站综合效益的重要手段。本文以长洲水利枢纽为例,针对低水头大型水利枢纽调度过程中面临库区上游淹没制约、下游尾水顶托、机组出力受限等多约束问题... 水库汛期运行水位动态控制是促进雨洪资源利用、缓解水库防洪与兴利之间矛盾、提高水电站综合效益的重要手段。本文以长洲水利枢纽为例,针对低水头大型水利枢纽调度过程中面临库区上游淹没制约、下游尾水顶托、机组出力受限等多约束问题,构建了适用于此类工程的防洪与发电多目标联合优化调度模型,提出基于淹没临界控制线的调洪演算方法和发电流量逐次分配优化求解方法。通过长系列模拟演算和多方案对比分析发现,与常规方案相比,采用运行水位动态控制方案可以使枢纽汛期平均发电水头提升6.88%、平均发电量增加8.75%,经济效益显著。研究方法对低水头大型水利枢纽防洪与发电联合优化调度具有借鉴意义。 展开更多
关键词 低水头 洪水调度 水位动态控制 发电调度 长洲水利枢纽
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FACILITATING REGIONAL SUSTAINABLE DEVELOPMENT THROUGH INTEGRATED MULTI-OBJECTIVE UTILIZATION, MANAGEMENT OF WATER RESOURCES IN THE LANCANG-MEKONG RIVER BASIN 被引量:3
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作者 He Daming Centre for Environmental Evolution and Sustainable Development, Yunnan Institute of Geography, Kunming, China 650223 Hsiang te Kung Memphis University, TN 38152, USA 《Journal of Geographical Sciences》 SCIE CSCD 1997年第4期9-21,共13页
The Lancnag Mekong River is the most important international river across China and Southeast Asia, If it is developed according to 'Great Mekong Subregional Cooperation Plan' [9] prepared by ADB, the area di... The Lancnag Mekong River is the most important international river across China and Southeast Asia, If it is developed according to 'Great Mekong Subregional Cooperation Plan' [9] prepared by ADB, the area directly affected will be up to over 2.32 million km 2, the population over 220 million, and the natural environment, and socio-economic conditions within a large area will be greatly changed. 'Agreement on Cooperation for Sustainable Development of Mekong Basin' signed by the four riparian countries along the lower Mekong River on April 5, 1995 provides a new opportunity for sustainable development of the Basin. According to preliminary analysis, if the multipurpose utilization of the water resources is the target for carrying out integrated planning and management, and the efforts are made 1) to focus on energy exploitation on the Lancang River Mainstream and the tributaries of the lower Mekong River; 2) to build gated weirs at Tonle Sam; 3) to construct spillways at the Mekong Delta; 4) to facilitate flood dykes in big cities and on both banks of the mainstream which are concentrated with population and farmland and liable to be flooded, and 5) to strengthen networks for forecasting hydrological and meteorological conditions, then all problems such as power demand, irrigation, flood, salt water intrusion as well as acid water erosion to soil could be solved without constructing large cascaded stations and dams on the lower Mekong Mainstream. This will not only avoid input of great number of fund, large scale resettlement and land inundation, but also prevent aquatic organisms living in Mekong River from being injured due to dam construction, and promote the sustainable development of the Basin. 展开更多
关键词 Lancang-Mekong River multi purpose planning water resources sustainable development drainage basin.
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Selection Method of Multi-Objective Problems Using Genetic Algorithm in Motion Plan of AUV 被引量:3
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作者 ZHANG Ming-jun , ZHENG Jin-xing , ZHANG Jing College of Mechanical and Electrical Engineering, Harbin Engineering University, Harbin 150001 ,China College of Computer and Information Science, Harbin Engineering University, Harbin 150001 , China 《Journal of Marine Science and Application》 2002年第1期81-86,共6页
To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an o... To research the effect of the selection method of multi-objects genetic algorithm problem on optimizing result, thismethod is analyzed theoretically and discussed by using an autonomous underwater vehicle(AUV) as an object. A changingweight vtlue method is put forward and a selection formula is modified. Some experiments were implemented on an AUV.TwinBurger. The results shows that this method is effective and feasible. 展开更多
关键词 AUV multi - objective optimization GENETIC algorithm SELECTION method
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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:39
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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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基于人-车-土系统的撒肥机组能耗与一源多用潜力分析
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作者 沈春雷 胡春雨 +3 位作者 葛雯 杨晓 陈月锋 杨敏丽 《农业机械学报》 EI CAS CSCD 北大核心 2023年第S01期419-426,共8页
针对“人-车-土”作业系统下重型撒肥机组油耗因素机制不清和农机单次作业期短、作业频次低导致的农机“电源撂荒”问题,分析“人-车-土”系统油耗结构方程模型互作机制并预测纯电动拖拉机电源“一源多用”模式对“生活-生态”的增益潜... 针对“人-车-土”作业系统下重型撒肥机组油耗因素机制不清和农机单次作业期短、作业频次低导致的农机“电源撂荒”问题,分析“人-车-土”系统油耗结构方程模型互作机制并预测纯电动拖拉机电源“一源多用”模式对“生活-生态”的增益潜力。首先,开展重型拖拉机撒肥作业田间综合试验,采集驾驶员疲劳度、拖拉机燃油油耗、耕层土壤表征量等作业要素数据,建立驾驶员-拖拉机-耕层土壤的油耗结构方程模型;然后,基于结构方程因果关系探寻农机油耗因子间相关性;最后,基于油耗等值转换理论计算燃油农机等效需电量与碳排放量,预测纯电动拖拉机“一源多用”模式对生产生活电源互换共享与减排降碳的贡献潜力。结果表明:耕层土壤紧实度是拖拉机主要油耗影响因素;驾驶员操作疲劳对油耗具有间接影响,可通过操纵拖拉机间接影响耕层物理性质和拖拉机碳排放、作业效率。电动拖拉机电源“一源多用”对农网末端小型用电设施供电具有一定潜力,在机械化田间管理期,等效耗电量约为45 kW·h/hm^(2),减少碳排放12 kg/hm^(2)(CO_(2)),中小规模农场可减少农机碳排放约2464 t(CO_(2)),节约电9.24×10^(6) kW·h,并且其电源闲置时提供约110 t玉米烘干所需电力,或165台通风设备全天同时通风所需电力,或5500个路灯夜间照明的电能,或11个值班室全年的用电需求。 展开更多
关键词 油耗特性结构方程模型 一源多用 电能替代 --土系统
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Model and algorithm of flow interception problem with multi-type of flows
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作者 Hu Dandan Yang Chao Yang Jun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第4期755-761,共7页
To study simultaneous location of different kinds of facilities, a new model of flow interception problem with multi-type of flows is proposed, with the consideration of multi-purpose flows and the influence of facili... To study simultaneous location of different kinds of facilities, a new model of flow interception problem with multi-type of flows is proposed, with the consideration of multi-purpose flows and the influence of facilities on each other. To be more practical, the objective is to maximize the benefits from flow-by customers instead of maximizing flows in the past. Since this problem is NP-hard and there is no optimal solution for large network, greedy and improved greedy heuristic algorithms are proposed. A computational example is presented to show that the optimal location decisions are proved to be strongly dependent on the influence coefficients and average profits by one customer and different types of facilities are almost co-located. Finally the results of sensitivity analysis are reported. 展开更多
关键词 LOCATION flow interception greedy heuristic multi-purpose influence coefficient
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基于D-S证据理论多源信息融合与配电网故障行波分析
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作者 冯建辉 孔碧光 《云南电力技术》 2023年第1期51-54,共4页
多源信息融合与单一信息源故障定位相比,故障定位能够充分利用电力系统自动化设备,例如将更多的卡尔曼滤波、贝叶斯理论、D-S证据理论、聚类分析、人工神经网络、专家知识系统、模糊集理论、粗糙集理论等信息汇集到一起,大幅提升故障定... 多源信息融合与单一信息源故障定位相比,故障定位能够充分利用电力系统自动化设备,例如将更多的卡尔曼滤波、贝叶斯理论、D-S证据理论、聚类分析、人工神经网络、专家知识系统、模糊集理论、粗糙集理论等信息汇集到一起,大幅提升故障定位的准确性。结合多源信息融合技术相关理论与D-S证据理论,在故障发生后行波的各种特性进行分析,对于故障定位与行波装置配置研究提供相应的参考理论支持。 展开更多
关键词 D-S证据 多源信息融合 配电网故障 行波分析
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新文科建设引领下的专门用途英语教学发展研究
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作者 于瑶 《金融理论与教学》 2024年第1期96-99,共4页
新文科建设是高等外语教育改革的重要契机,专门用途英语(ESP)是英语教学危机的应变之举。ESP是与某一特定学科或行业相关的英语语言教学与研究,分为学术用途英语和行业用途英语两大类。无论是公共英语教学还是英语类专业教学,ESP教学都... 新文科建设是高等外语教育改革的重要契机,专门用途英语(ESP)是英语教学危机的应变之举。ESP是与某一特定学科或行业相关的英语语言教学与研究,分为学术用途英语和行业用途英语两大类。无论是公共英语教学还是英语类专业教学,ESP教学都在一定程度上面临课程定位不够明确,以及教学体系不够成熟的发展困境。明确专门用途英语的课程定位,实施以社会需求为基、以学习需求为纲的多元主体协同育人教学策略,是新文科建设引领下的ESP破局路径。 展开更多
关键词 新文科 专门用途英语 需求分析 多元主体协同育人
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多目标区域地球化学调查与土壤碳储量问题--以江苏、湖南、四川、吉林、内蒙古为例 被引量:61
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作者 奚小环 张建新 +3 位作者 廖启林 陈德友 白荣杰 黄增芳 《第四纪研究》 CAS CSCD 北大核心 2008年第1期58-67,共10页
在全国多目标区域地球化学调查获得土壤高密度和大数据量碳分布数据基础上,提出"单位土壤碳含量"概念和建立土壤碳储量实测计算方法,为精确计算土壤碳储量和估算土壤碳库提供了新的途径。依据"单位土壤碳含量"进行... 在全国多目标区域地球化学调查获得土壤高密度和大数据量碳分布数据基础上,提出"单位土壤碳含量"概念和建立土壤碳储量实测计算方法,为精确计算土壤碳储量和估算土壤碳库提供了新的途径。依据"单位土壤碳含量"进行土壤碳储量实测计算,可以按照土壤类型、土地利用分类、生态系统及自然景观等任意划分方式,从不同途径取得市县、省区、流域及至国家土壤碳储量,并在各级次上进行土壤碳库问题研究,解决土地利用、农业种植和环境评估中的实际问题。文章以江苏、湖南、四川、吉林、内蒙古为例进行土壤有机碳储量计算,结果表明,全国土壤碳储量分布不均匀。按照土壤有机碳储量和土壤平均有机碳储量分布,四川省四川盆地西部区土壤有机碳储量为1779887583t,平均有机碳储量最高,为29107.86t/km2;依次为:吉林省平原区有机碳储量2618973357t,平均有机碳储量27427.25t/km2;湖南省洞庭湖区有机碳储量837159672t,平均有机碳储量21977.31t/km2;江苏省有机碳储量1818603526t,平均有机碳储量17117.61t/km2;内蒙古河套地区有机碳储量286247058t,平均有机碳储量9592.73t/km2。 展开更多
关键词 多目标区域地球化学调查 采样与测试 单位土壤碳含量 实测计算方法 土壤碳储量 土壤平均 碳储量 研究级次划分 实例
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基于多元目标的主成分分析的热岛效应成因研究--以西安市为例 被引量:6
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作者 冯晓刚 撒利伟 石辉 《西安建筑科技大学学报(自然科学版)》 CSCD 北大核心 2012年第4期507-511,共5页
城市热岛效应作为城市化进程的负效应,其成因具有复杂性和地域性特征.以西安市为例,基于多元目标分析的主成分方法定量计算了不同影响因子对西安市热岛效应的贡献度大小,并以此为基础,最终筛选了城市人口、人均拥有道路面积、人均拥有... 城市热岛效应作为城市化进程的负效应,其成因具有复杂性和地域性特征.以西安市为例,基于多元目标分析的主成分方法定量计算了不同影响因子对西安市热岛效应的贡献度大小,并以此为基础,最终筛选了城市人口、人均拥有道路面积、人均拥有机动车数、人均绿化面积、建成区面积、降水量及平均风速7个主要因素作为西安市热岛效应的主要成因;最后,从调整城市规划思路、控制工业热源、调控民用热源等三个方面为出发点构建了应对西安市热岛效应的宏观调控体系,其内容由3个一级指标、12个二级指标和5个三级指标构成.对应对和缓解西安市热岛效应具有积极的指导意义,也为其它城市应对热岛效应提供范式参考. 展开更多
关键词 城市热岛 成因分析 主成分分析 多元目标 西安市
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