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Safety assessment of approximate segregated parallel operation on closely spaced parallel runways
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作者 Fei LIU Xinze LIU +1 位作者 Mingjiang MOU Zhiqiang WEI 《中国航空学报:英文版》 SCIE EI CAS CSCD 2019年第2期463-476,共14页
With the continuous growth of air traffic flow, some airports in China or other countries begin to construct Closely Spaced Parallel Runways(CSPR) to meet the capacity requirement of civil aviation. In this paper, the... With the continuous growth of air traffic flow, some airports in China or other countries begin to construct Closely Spaced Parallel Runways(CSPR) to meet the capacity requirement of civil aviation. In this paper, the simulation and calculation method of flight trajectory is developed,as well as the collision risk calculation method and wake vortex encounter risk calculation method.New methods for departure and go-around procedures are proposed to achieve approximate segregated parallel operation in an attempt to obtain approximately the same results on closely spaced parallel runways as on widely spaced parallel runways. By comparing with the independent parallel departure and segregated parallel operation in ICAO Doc. 9643, it is found that the lateral separation between aircraft in this proposal is not less than the separations in the other two cases. Based on the simulation calculation of flight trajectories under different conditions, the probabilities of collision conflict and encountering wake vortex are lower than those in current operation plan.The proposed plan has no special requirements in pilot operation, control command procedures,airport facilities, or meteorological observation and prediction, so it is convenient to promote and implement at the airports with closely spaced parallel runways. 展开更多
关键词 AIR traffic control AIR transportation Closely spaced PARALLEL runways Segregated PARALLEL operation WAKE VORTEX ENCOUNTER WAKE VORTEX separation standards
Dynamic Performance Evaluation of a Redundantly Actuated and Over-constrained Parallel Manipulator
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作者 Hai-Qiang Zhang Hai-Rong Fang +1 位作者 Bing-Shan Jiang Shuai-Guo Wang 《国际自动化与计算杂志:英文版》 EI CSCD 2019年第3期274-285,共12页
This paper presents a redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator with two rotational and one translational coupling degrees of freedom.The kinematics analysis is firstly carried out and... This paper presents a redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator with two rotational and one translational coupling degrees of freedom.The kinematics analysis is firstly carried out and the mapping relationship of the velocity,acceleration and the independent parameters between the actuator joint and the moving platform are deduced by using the vector dot product and cross product operation.By employing d′Alembert′s principle and the principle of virtual work,the dynamics equilibrium equation is derived,and the simplified dynamics mathematical model of the parallel manipulator is further derived.Simultaneously,the generalized inertia matrix which can characterize the acceleration performance between joint space and operation space is further separated,and the performance indices including the dynamics dexterity,inertia coupling characteristics,energy transmission efficiency and driving force/torque balance are introduced.The analysis results show that the proposed redundantly actuated and over-constrained 2 RPU-2 SPR parallel manipulator in comparison with the existing non-redundant one has better dynamic comprehensive performance,which can be demonstrated practically by the successful application of the parallel kinematic machine head module of the hybrid machine tool. 展开更多
关键词 Redundantly actuated over-constrained PARALLEL MANIPULATOR DYNAMICS performance index
基于图游走的并行协同过滤推荐算法 预览
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作者 顾军华 谢志坚 +2 位作者 武君艳 许馨匀 张素琪 《智能系统学报》 CSCD 北大核心 2019年第4期743-751,共9页
针对目前协同过滤推荐算法存在的数据稀疏性问题和可扩展性问题,本文进行了相关研究。针对稀疏性问题,在传统的皮尔逊相关相似度中引入交占比系数计算用户间直接相似度,该方法缓解了用户间共同评分项的占比问题;提出一种基于图游走的间... 针对目前协同过滤推荐算法存在的数据稀疏性问题和可扩展性问题,本文进行了相关研究。针对稀疏性问题,在传统的皮尔逊相关相似度中引入交占比系数计算用户间直接相似度,该方法缓解了用户间共同评分项的占比问题;提出一种基于图游走的间接相似度计算方法,该方法根据用户间的直接相似度建立用户网络图,在用户网络图上通过游走计算用户间的间接相似度,并进行推荐。在Spark平台上实现本文方法的并行化,缓解了数据规模增加带来的可扩展性问题。实验结果表明:本文提出的算法在不同数据集上均取得了良好效果,有效地提高了推荐准确度,并且在分布式环境下具有良好的可扩展性。 展开更多
关键词 协同过滤 推荐 用户网络图 游走 相似度 间接相似度 并行 Spark平台
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并行高吞吐率多模极化码编码器设计 预览
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作者 刘丽华 管武 梁利平 《计算机工程》 CAS CSCD 北大核心 2019年第4期72-77,共6页
为获得可以支持多种码长、具有更高吞吐率的极化码编码器,提出一种32 bit并行级联的多模极化码编码器结构。每时钟周期内更新生成矩阵的32行,进行32 bit并行编码,从而加快编码速度。通过两级编码结构的级联简化编码器结构,以支持64 bit~... 为获得可以支持多种码长、具有更高吞吐率的极化码编码器,提出一种32 bit并行级联的多模极化码编码器结构。每时钟周期内更新生成矩阵的32行,进行32 bit并行编码,从而加快编码速度。通过两级编码结构的级联简化编码器结构,以支持64 bit~4 096 bit码长的极化码编码。实验结果表明,在Xilinx XC6VLX240t的FPGA上,该编码器主频为303.82 MHz,吞吐率为9.72 Gb/s,寄存器与查找表资源相比快速傅里叶变换结构分别降低了77.6%与63.3%,在65 nm CMOS工艺下主频可达0.796 GHz,吞吐率可达24.615 Gb/s。 展开更多
关键词 极化码编码器 高吞吐率 并行 多模 ASIC实现
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Optimal Design and Force Control of a Nine-Cable-Driven Parallel Mechanism for Lunar Takeoff Simulation
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作者 Wangmin Yi Yu Zheng +3 位作者 Weifang Wang XiaoqiangTang Xinjun Liu Fanwei Meng 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第4期35-46,共12页
Traditional simulation methods are unable to meet the requirements of lunar takeo simulations, such as high force output precision, low cost, and repeated use. Considering that cable-driven parallel mechanisms have th... Traditional simulation methods are unable to meet the requirements of lunar takeo simulations, such as high force output precision, low cost, and repeated use. Considering that cable-driven parallel mechanisms have the advantages of high payload to weight ratio, potentially large workspace, and high-speed motion, these mechanisms have the potential to be used for lunar takeo simulations. Thus, this paper presents a parallel mechanism driven by nine cables. The purpose of this study is to optimize the dimensions of the cable-driven parallel mechanism to meet dynamic workspace requirements under cable tension constraints. The dynamic workspace requirements are derived from the kinematical function requests of the lunar takeo simulation equipment. Experimental design and response surface methods are adopted for building the surrogate mathematical model linking the optimal variables and the optimization indices. A set of dimensional parameters are determined by analyzing the surrogate mathematical model. The volume of the dynamic workspace increased by 46% after optimization. Besides, a force control method is proposed for calculating output vector and sinusoidal forces. A force control loop is introduced into the traditional position control loop to adjust the cable force precisely, while controlling the cable length. The e ectiveness of the proposed control method is verified through experiments. A 5% vector output accuracy and 12 Hz undulation force output can be realized. This paper proposes a cable-driven parallel mechanism which can be used for lunar takeo simulation. 展开更多
关键词 FORCE control LUNAR TAKEOFF SIMULATION Parallel ROBOTS Surrogate mathematical model
Full electromagnetic transient simulation for large power systems
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作者 Yong Tang Lei Wan Junxian Hou 《全球能源互联网:英文版》 2019年第1期29-36,共8页
For building Global Energy Interconnection(GEI), it is necessary to implement new breakthroughs on largepower system simulation. Key routes for implementing full electromagnetic transient simulation of large-power sys... For building Global Energy Interconnection(GEI), it is necessary to implement new breakthroughs on largepower system simulation. Key routes for implementing full electromagnetic transient simulation of large-power systems are described in this paper, and a top framework is designed. A combination of the new large time step algorithm and the traditional small-time step algorithm is proposed where both parts A and B are calculated independently. The method for integrating the Norton equivalence of the power electronic system to the entire power grid is proposed. A two-level gird division structure is proposed, which executes a multi-rate parallel calculation among subsystems and element parallel calculation in each subsystem. The initialization method of combining load flow derivation and automatic trial-and-error launching is introduced. The feasibility of the method is demonstrated through a practical power grid example, which lays a foundation for further research. 展开更多
关键词 Global Energy Intercorinection POWER system Electromagnetic TRANSIENT EQUIVALENCE Machine-network in terface Parallel calculati on POWER electro NICS INITIALIZATION Technology framework CLC
基于车辆异常行为的套牌车并行检测方法 预览
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作者 康晨傲 曾献辉 《智能计算机与应用》 2019年第3期11-15,22共6页
面对套牌车问题,当前检测技术误判率居高不下,稽查部门需要消耗大量人力资源审核检测结果。为了降低套牌车检测的误判率和虚警率,提出了一种基于车辆异常行为的套牌车并行检测方法。确立数种与套牌车相关联的车辆异常行为因素,针对海量... 面对套牌车问题,当前检测技术误判率居高不下,稽查部门需要消耗大量人力资源审核检测结果。为了降低套牌车检测的误判率和虚警率,提出了一种基于车辆异常行为的套牌车并行检测方法。确立数种与套牌车相关联的车辆异常行为因素,针对海量通行数据,利用分布式架构建立相应异常行为的挖掘算法模型,并对某市高速公路的真实海量交通流数据进行挖掘;利用BP神经网络算法建立模型并对数种异常行为挖掘结果进行训练,从而综合考虑多种异常行为因素得出套牌车检测结果。研究结果表明,该并行检测算法有效地降低套牌车误判率至18%,可大幅度提高稽查人员的工作效率。 展开更多
关键词 套牌车检测 车辆异常行为 大数据 并行 SPARK 高速公路
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平行观察[壹] 预览
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作者 张利 《世界建筑》 2019年第2期8-9,共2页
本期《世界建筑》是我们对热带(包括部分亚热带)亚洲当代建筑观察的第一部分,聚焦于斯里兰卡和印度。如果把斯里兰卡和印度当代建筑的发展路径与我国当代建筑的发展路径进行比较,不难发现一些平行的典型特征。这与20世纪中期以来除日本... 本期《世界建筑》是我们对热带(包括部分亚热带)亚洲当代建筑观察的第一部分,聚焦于斯里兰卡和印度。如果把斯里兰卡和印度当代建筑的发展路径与我国当代建筑的发展路径进行比较,不难发现一些平行的典型特征。这与20世纪中期以来除日本外的整个亚洲所经历的民族独立与发展历程是密切相关的。 展开更多
关键词 发展 民族 建筑 印度 平行 路径 亚洲
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汽动引风机不同并列方法的探讨 预览
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作者 沈霄华 董先平 +2 位作者 施宇 秦涛 廖红涛 《湖州师范学院学报》 2019年第2期68-72,共5页
以华能长兴电厂为例,介绍该厂两台汽动引风机通过转速进行并列的不同方法,并通过经济性、安全性、操作复杂性及引风机工作汽源等的比较,分析了两种并列方法各自的优缺点及注意事项,提出了新的汽动引风机并列方案.
关键词 汽动引风机 转速 并列 汽源
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Cloud-based parallel power flow calculation using resilient distributed datasets and directed acyclic graph 预览
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作者 Dewen WANG Fangfang ZHOU Jiangman LI 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第1期65-77,共13页
With the integration of distributed generation and the construction of cross-regional long-distance power grids, power systems become larger and more complex.They require faster computing speed and better scalability ... With the integration of distributed generation and the construction of cross-regional long-distance power grids, power systems become larger and more complex.They require faster computing speed and better scalability for power flow calculations to support unit dispatch.Based on the analysis of a variety of parallelization methods, this paper deploys the large-scale power flow calculation task on a cloud computing platform using resilient distributed datasets(RDDs).It optimizes a directed acyclic graph that is stored in the RDDs to solve the low performance problem of the MapReduce model.This paper constructs and simulates a power flow calculation on a large-scale power system based on standard IEEE test data.Experiments are conducted on Spark cluster which is deployed as a cloud computing platform.They show that the advantages of this method are not obvious at small scale, but the performance is superior to the stand-alone model and the MapReduce model for large-scale calculations.In addition, running time will be reduced when adding cluster nodes.Although not tested under practical conditions, this paper provides a new way of thinking about parallel power flow calculations in large-scale power systems. 展开更多
关键词 Power flow calculation PARALLEL programming MODEL DISTRIBUTED memory-shared MODEL Resilient DISTRIBUTED datasets(RDDs) Directed ACYCLIC graph(DAG)
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天空区域分割的图像去雾及CUDA并行实现
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作者 曾浩洋 张红英 《小型微型计算机系统》 CSCD 北大核心 2019年第3期655-659,共5页
针对暗原色先验去雾算法对大面积天空区域处理不理想等问题,提出了一种基于天空区域分割的图像去雾算法.该算法首先使用最大类间方差法(Otsu)求得阈值将天空与非天空区域分割开,然后再对天空区域求大气光值A,作为整幅雾天图像的大气光值... 针对暗原色先验去雾算法对大面积天空区域处理不理想等问题,提出了一种基于天空区域分割的图像去雾算法.该算法首先使用最大类间方差法(Otsu)求得阈值将天空与非天空区域分割开,然后再对天空区域求大气光值A,作为整幅雾天图像的大气光值,进而精细化透射率,得到较好的复原效果.为了提高去雾效率,基于CUDA(Common Unified Device Architecture)并行编程算法,通过GPU并行处理和CPU任务调度的协同,在保证去雾效果的同时快速去雾.实验结果表明,该方法能很好的解决天空区域去雾出现的光晕和色彩失真现象.优化后的并行算法,针对高清图像基本上达到了实时去雾的效果. 展开更多
关键词 图像去雾 暗原色先验 OTSU CUDA GPU 并行
提高ArcGIS地理处理工具执行效率的方法研究 预览
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作者 杨霄翼 《测绘与空间地理信息》 2019年第1期181-183,190共4页
ArcGIS地理处理工具因其专业性和易用性,在GIS领域被广泛使用,但由于默认状态下工具不能自主地充分利用硬件资源而需要优化。本文在分析ArcGIS Desktop软件特点以及GP工具执行特点的基础上,提出了通过开启64位后台地理处理的非并行方式... ArcGIS地理处理工具因其专业性和易用性,在GIS领域被广泛使用,但由于默认状态下工具不能自主地充分利用硬件资源而需要优化。本文在分析ArcGIS Desktop软件特点以及GP工具执行特点的基础上,提出了通过开启64位后台地理处理的非并行方式以及设置"并行因子"、并行ArcMap软件、GP工具的Python脚本并行调用提高执行效率的方法,并通过对比测试揭示了不同优化方法的优化效果和特质。 展开更多
关键词 ARCGIS 地理处理工具 执行效率 并行 PYTHON
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Parallel transjugular intrahepatic portosystemic shunt with Viatorr? stents for primary TIPS insufficiency: Case series and review of literature 预览
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作者 Driss Raissi Qian Yu +1 位作者 Michael Nisiewicz Steven Krohmer 《世界肝病学杂志:英文版(电子版)》 2019年第2期217-225,共9页
BACKGROUND Transjugular intrahepatic portosystemic shunts (TIPS) can alleviate complications of portal hypertension such as ascites and variceal bleeding by decreasing the portosystemic gradient. In limited clinical s... BACKGROUND Transjugular intrahepatic portosystemic shunts (TIPS) can alleviate complications of portal hypertension such as ascites and variceal bleeding by decreasing the portosystemic gradient. In limited clinical situations, parallel TIPS may be only solution to alleviate either variceal bleeding or ascites secondary to portal hypertension when the primary TIPS fails to do so. Data specifically addressing the use of this partially polytetrafluoroethylene covered nitinol stent (Viatorr■) is largely lacking despite Viatorr■ being the current gold standard for modern TIPS placement. CASE SUMMARY All three patients had portal hypertension and already had a primary Viatorr■ TIPS placed previously. All patients have undergone failed endoscopy to manage acute variceal bleeding before referral for a parallel stent (PS). PS were placed in patients presenting with recurrent variceal bleeding despite existence of a widely patent primary TIPS. Primary stent patency was verified with either Doppler ultrasound or intra-procedural TIPS stent venography. Doppler ultrasound follow-up imaging demonstrated complete patency of both primary and parallel TIPS. All three patients did well on clinical follow-up of up to six months and no major complications were recorded. A review of existing literature on the role of PS in the management of portal hypertension complications is discussed. There are three case reports of use of primary and PS Viatorr? stents placement, only one of which is in a patient with gastrointestinal variceal bleeding despite a patent primary Viatorr? TIPS. CONCLUSION Viatorr?PS placement in the management of variceal hemorrhage is feasible with promising short term patency and clinical follow-up data. 展开更多
关键词 Transjugular INTRAHEPATIC portosystemic SHUNT PARALLEL stent Portal hypertension VARICES Viatorr? Tandem Double BARREL Case report
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雷击输电线路对并行10kV配电线路影响分析
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作者 申东玄 杨仲江 +1 位作者 刘健 肖扬 《高压电器》 CAS CSCD 北大核心 2019年第4期211-216,共6页
由于线路走廊有限,10 kV配电线路与输电线路会出现并行架设,需要分析输电线路遭受雷击后对配电线路防护产生的影响。文中分析输电线路避雷线遭受雷击对配电线路的电磁影响及输电线路对配电线路的屏蔽保护作用,利用EMTP软件建立输电线路... 由于线路走廊有限,10 kV配电线路与输电线路会出现并行架设,需要分析输电线路遭受雷击后对配电线路防护产生的影响。文中分析输电线路避雷线遭受雷击对配电线路的电磁影响及输电线路对配电线路的屏蔽保护作用,利用EMTP软件建立输电线路与配电线路模型,计算雷击输电线路避雷线时配电线路感应过电压,分析避雷线高度、线路间水平间距、线路高度差和输电线路杆塔接地电阻对感应过电压的影响。分析结果表明:雷击输电线路避雷线时,配电线路感应过电压随着避雷线高度的增加而降低,但降低趋势趋缓。过电压随着二者间水平距离的增大而减小,且水平距离越远,降低幅度越大,过电压随二者高度差的增大而减小,高度差越大,减小幅度越大。线路感应过电压随着输电线路接地电阻的增大而增加。接地不良情况下线路感应过电压十分容易超过其绝缘水平,因此需要尽可能降低输电线路杆塔接地电阻。 展开更多
关键词 雷击 输电线路 并行 配电线路 感应过电压
Research on optimal drive joints configuration of a rolling robot of closed fivebow-shaped-bar linkage 预览
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作者 Zeng Xiangkuo 《石化技术》 CAS 2019年第6期88-88,256共2页
The relationship between the stability and the configuration of the driving joint was studied as a measure to improve the stability of robot.The Lagrange dynamic equation of the robot was established.According to the ... The relationship between the stability and the configuration of the driving joint was studied as a measure to improve the stability of robot.The Lagrange dynamic equation of the robot was established.According to the principle of virtual work,the least squares solution of each joint torque was obtained.The relationship between the stability of the robot and the configuration of the driving joint is obtained by the sum of the norms of the joint torque.Finally,numerical simulations verify the correctness of the theory. 展开更多
关键词 CLOSED five-bow-shaped-bar parallel mechanism Lagrange equation DRIVE JOINTS CONFIGURATION
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无线传感器网络轮询控制系统研究 预览 被引量:1
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作者 杨志军 孙洋洋 《云南大学学报:自然科学版》 CAS CSCD 北大核心 2019年第1期46-52,共7页
针对无线传感器网络节点能量有限的问题,提出了区分队列忙闲状态的并行调度限定(K=1)轮询控制系统.该系统根据队列所处的不同忙闲状态只对有信息数据分组的动态忙队列进行发送服务.采用马尔科夫链与概率母函数的方法建立了系统的数学模... 针对无线传感器网络节点能量有限的问题,提出了区分队列忙闲状态的并行调度限定(K=1)轮询控制系统.该系统根据队列所处的不同忙闲状态只对有信息数据分组的动态忙队列进行发送服务.采用马尔科夫链与概率母函数的方法建立了系统的数学模型,对其求偏导解析出了系统的查询周期、吞吐量、平均队长和平均时延等重要系统参数.模拟仿真结果与理论计算结果近似相等,表明了该理论分析方法的正确有效.该系统采用限定服务策略保障了系统公平性,而区分队列的忙闲状态又避免了对无数据信息分组的空闲队列的查询,因此能够大大降低系统的平均时延,提高系统的轮询控制效率.与已有的限定(K=1)服务策略相比较,在参数设置相同的情况下,系统的平均队长和平均时延明显降低. 展开更多
关键词 忙闲状态 并行 轮询策略 系统性能
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Constant frequency operation of parallel resonant converter for constant-current constant-voltage battery charger applications 预览
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作者 Taha Nurettin GüCIN Muhammet BIBEROGLU Bekir FINCAN 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第1期186-199,共14页
This paper proposes a design and control approach to parallel resonant converter(PRC) based battery chargers.The proposed approach is particularly suitable for the constant-current constant-voltage(CC-CV)charging meth... This paper proposes a design and control approach to parallel resonant converter(PRC) based battery chargers.The proposed approach is particularly suitable for the constant-current constant-voltage(CC-CV)charging method, which is the most commonly utilized one.Since the PRC is operated at two different frequencies for each CC and CV charging modes, this approach eliminates the need for complicated control techniques such as the frequency-control and phase-shift-control.The proposed method not only simplifies the design and implementation processes of the converter unit but also simplifies the design of output filter configuration and decreases the number of the required components for the control of the charger.The proposed method is confirmed by two experimental setups.The results show that the designed charger circuit ensured a very stable constant current in CC charging phase, where the charging current is fixed to 1.75 A.Although a voltage increase in CV phase is observed, the charger circuit is able to decrease the charging current to 0.5 A in CV phase, as depicted in battery data-sheet.The efficiency of the charger is figured out to be in the range of 86%-93% in the first setup, while it is found to be in the range of 78%-88% in the second setup,where a high frequency transformer is employed. 展开更多
关键词 RESONANT CONVERTER Parallel RESONANT CONVERTER Battery charger Constant-current constant-voltage(CC-CV) charging
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基于平行竞争PSO算法的土壤水分测量研究 预览
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作者 刘云潺 张慧宁 《节水灌溉》 北大核心 2019年第7期82-86,共5页
为了提高测量土壤水分Van Genuchten方程求解的精度,提出平行竞争PSO算法。首先在PSO算法基础上,当粒子群最大半径值小于某个阈值时,竞争才被触发,同时最差粒子被重置,粒子被重置的比例随着迭代次数增加而非线性减少;接着粒子群分成若... 为了提高测量土壤水分Van Genuchten方程求解的精度,提出平行竞争PSO算法。首先在PSO算法基础上,当粒子群最大半径值小于某个阈值时,竞争才被触发,同时最差粒子被重置,粒子被重置的比例随着迭代次数增加而非线性减少;接着粒子群分成若干子群,子群的群平均适应度与原始粒子群平均适应度相差不能小于设定的阈值,引入不同的共享因子对子群与子群、粒子与子群之间进行信息共享动态调节;最后粒子适应度函数由Van Genuchten方程参数构成,给出了算法流程。实验仿真显示本文算法对测试函数求解具有收敛速度较快、解精度较高的特点,测量粉壤土脱湿数据的相对误差最大为5%,吸湿数据的相对误差最大为4%,相比其他算法都较小。 展开更多
关键词 平行 竞争 土壤 水分
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西门子直流传动整流器的几种拓展应用 预览
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作者 边军 《甘肃冶金》 2019年第1期104-109,共6页
简要叙述了西门子直流电动机传动控制器的原理、设置、优化和调试。并具体分析了整流器的几种拓展应用,包括整流器的并联连接,12脉动串联连接,12脉动并联连接等几种模式,这些应用很好地解决了实际生产中的问题。最后指出随着我国钢铁工... 简要叙述了西门子直流电动机传动控制器的原理、设置、优化和调试。并具体分析了整流器的几种拓展应用,包括整流器的并联连接,12脉动串联连接,12脉动并联连接等几种模式,这些应用很好地解决了实际生产中的问题。最后指出随着我国钢铁工业的发展,不能固守直流传动,必须学习和应用新的交流变频传动控制技术。 展开更多
关键词 直流传动 整流器 并联 变频控制
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大数据环境下利用新型FTS的并行细节点指纹匹配通用分解方法 预览
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作者 李庆年 胡玉平 《重庆理工大学学报:自然科学》 CAS 北大核心 2019年第4期147-155,共9页
随着指纹识别数据库规模的不断扩大,指纹识别系统的通用性、可靠性亟须提高。为了解决该问题,提出了利用新型指纹拓扑结构(FTS)的并行化细节点指纹匹配分解方法。该方法首先根据k近邻算法设计了叉点和端点新的结构,并提取出细节点特征... 随着指纹识别数据库规模的不断扩大,指纹识别系统的通用性、可靠性亟须提高。为了解决该问题,提出了利用新型指纹拓扑结构(FTS)的并行化细节点指纹匹配分解方法。该方法首先根据k近邻算法设计了叉点和端点新的结构,并提取出细节点特征。然后,将匹配分数的计算过程分解为几个小步骤来执行,在更精细的层次上分割2个指纹的最终匹配,以此定义局部结构子集之间的部分分数。最后,单独计算这些部分分数,将它们合并在一起,构成一个非常灵活的预测值,并允许丢弃部分分数。此外,提出了基于细节点置信度的指纹匹配算法,有助于全局范围上的指纹信息提取,从而确保局部相似细节点的有效匹配。在SFinGe数据库上的实验结果表明:所提出的分解框架可适用于Apache Hadoop、Apache Spark等大数据环境,具有良好的可靠性。将提出的分解方法应用于3种匹配算法中进行实验,结果表明提出的分解方法具有良好的通用性。 展开更多
关键词 指纹拓扑结构(FTS) 并行化 置信度 K近邻算法 大数据
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