DA42MPP双载荷测绘型特种飞机航测应用案例分析

2015年10月,基于钻石DA42 MPP平台的双载荷测绘型特种飞机在奥地利完成了首次验证飞行[1]。本文对DA42 MPP飞机平台的性能与特性,双载荷系统的组成与架构做了介绍,并对此次验证飞行案例中的飞行数据和测绘数据的质量、精度进行了分析与评估。结果表明,双载荷系统可以同时协同工作,所获取的航测数据的质量与精度满足测绘行业的国家规范和标准,基于钻石DA42 MPP的双载荷测绘型特种飞机能够满足航拍航测任务。     

High-accuracy maximum power point estimation for photovoltaic arrays

Quantitative information regarding the maximum power point (MPP) of photovoltaic (PV) arrays is crucial for determining and controlling their operation, yet it is difficult to obtain such information through direct measurements. PV arrays exhibit an extremely nonlinear current-voltage (I-V) characteristic that varies with many complex factors related to the individual cells, which makes it difficult to ensure an optimal use of the available solar energy and to achieve maximum power output in real time. Finding ways to obtain the maximum power output in real time under all possible system conditions are indispensable to the development of feasible PV generation systems. The conventional methods for tracking the MPP of PV arrays suffer from a serious problem that the MPP cannot be quickly acquired. Based on the p-n junction semiconductor theory, we develop a prediction method for directly estimating the MPP for power tracking in PV arrays. The proposed method is a new and simple approach with a low calculation burden that takes the resistance effect of the solar cells into consideration. The MPP of PV arrays can be directly determined from an irradiated I-V characteristic curve. The performance of the proposed method is evaluated by examining the characteristics of the MPP of PV arrays depending on both the temperature and irradiation intensity, and the results are discussed in detail. Such performance is also tested using the field data. The experimental results demonstrate that the proposed method helps in the optimization of the MPP control model in PV arrays.     

Enhancement of grid-connected photovoltaic system using ANFIS-GA under different circumstances

In recent years, many different techniques are applied in order to draw maximum power from photovoltaic (PV) modules for changing solar irradiance and temperature conditions. Generally, the output power generation of the PV system depends on the intermittent solar insolation, cell temperature, efficiency of the PV panel and its output voltage level. Consequently, it is essential to track the generated power of the PV system and utilize the collected solar energy optimally. The aim of this paper is to simulate and control a grid-connected PV source by using an adaptive neuro-fuzzy inference system (ANFIS) and genetic algorithm (GA) controller. The data are optimized by GA and then, these optimum values are used in network training. The simulation results indicate that the ANFIS-GA controller can meet the need of load easily with less fluctuation around the maximum power point (MPP) and can increase the convergence speed to achieve the MPP rather than the conventional method. Moreover, to control both line voltage and current, a grid side P/Q controller has been applied. A dynamic modeling, control and simulation study of the PV system is performed with the Matlab/Simulink program.     

碳酸镍对MPP/PEPA阻燃PP性能的影响

采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的无卤阻燃PP,研究了碳酸镍(NC)用量对PP阻燃和力学性能的影响。结果表明:添加少量的NC即可显著提高材料的阻燃性能;当MPP/PEPA/NC用量分别为12%、8%和3%时,阻燃PP的氧指数高达37.5%,并具有较好的力学性能。TGA和EDX分析结果表明:添加NC可以催化MPP/PEPA间的酯化反应,促进材料成炭,并且在炭层中保留了更多的磷;SEM分析表明,NC可以起到稳定炭层,增加炭层厚度的作用。     

MPP+和6-羟基多巴胺对C6胶质瘤细胞摄取谷氨酸的影响1

目的 研究1-甲基-4-苯基-吡啶离子(MPP⁺)6-羟基多巴胺(6-OHDA)对C6 胶质瘤细胞摄取谷氨酸(Glu)的影响。方法 应用放射免疫法测定C6胶质瘤细胞对培养液中[³H] -D,L-谷氨酸的摄取;应用四氮唑(MTT)比色法检测胶质瘤细胞的活性。结果 6-OHDA 和MPP⁺均不同程度地抑制C6 胶质瘤细胞摄取Glu;6-OHDA 显著抑制C6 胶质瘤细胞活性,而MPP⁺却不影响细胞活性;蛋白激酶C(PKC)激动剂TPA 显著增强C6 细胞对Glu 的摄取,并拮抗MPP⁺对C6 细胞摄取Glu 的抑制。结论 6-OHDA 抑制C6 胶质瘤细胞对Glu 的摄取,可能与其抑制细胞活性有关,而MPP⁺的抑制作用可能与直接影响转运体的摄取功能有关,并可能由PKC 途径介导。     

分布式并行计算环境PVM

本文着重介绍了支持分布式计算的并行虚拟机系统(PVM).PVM能够利用现有网络连接的计算机实现并行处理,不但充分利用了网络资源,而且为普通用户进行并行处理提供了有力的工具.     

关于大规模并行处理机系统可扩展性设计

大规模并行处理系统旨在满足国防和国民经济许多重要应用领域对高性能计算能力的需求。长期以来,结构上的可扩性和编程上的友好性一直是并行计算机系统设计中追求的重要而又互相矛盾的两个目标。章结合研究实践,对大规模并行处理机系统（MPP）可扩展性设计的若干问题进行探讨。     

MPP同步机制中忙等待锁算法研究

对MPP中的3种基本类型的同步问题进行简单介绍;对忙等待锁的实现进行分析,指出一次这样的同步操作包括的几个阶段;对典型的忙等待锁算法进行详细的分析和比较,找到了这些算法的优点及其在使用上的限制,并对锁算法的选择进行了推荐。     

基于边界扫描的大型多处理器系统的硬件调试

设计和实现了一个基于边界扫描的通用通路测试平台,在某大型计算机系统和嵌入式应用系统中得到了应用.简述了边界扫描机制的工作原理,描述了该平台的软件结构和通路测试算法,并介绍了系统的应用情况.     

基于MPP环境的单纯形算法并行特性剖析

对MPP大规模并行计算环境下的线性规划问题单纯形算法的并行特性作了详细分析,并给出了适合于这一环境的并行单纯形算法．