Dynamic response simulation and experiment for gamma-type Stirling engine

This study presents a dynamic model of a gamma-type Stirling engine and examines variations of the crank rotational speed against time (Dynamic response). Kinematic relations of the engine linkages were determined and Lagrange formulations were formed for rigid body dynamics. Working gas pressures on each surface of the rigid bodies were calculated over time using a third order thermodynamic analysis code. A test setup was established for measuring dynamic and thermodynamic state variables of ST500engine. First, experiment data was used to validate the thermodynamic code results. Then the dynamic formulations combined with the thermodynamic code were simultaneously solved and the result is compared to ST500 dynamic response. Finally, using the whole dynamic model, new aspects of Stirling engine behavior were investigated. The dynamic–thermodynamic combination of the model gives the opportunity to instantly calculate a precise open-loop response, which is the essential part of designing proper load controllers for inherently unstable Stirling engines.     

Implementing an emerging mobility model for a fleet of UAVs based on a fuzzy logic inference system

In this paper, we design and implement a novel generic mobility model, named Alpha-based, for a fleet of small interconnected UAVs (Unmanned Aerial Vehicles) that collaborate to explore a geographic area (battle field, research and rescue missions, surveillance applications, etc.). In fact, due to the significant impact of mobility models on the networking performance, the mobility models must realistically capture the UAV’s attributes. Hence, we propose to use a combination of energy level, coverage-area and network connectivity for mobility decision-making, in contrast to the literature where only network connectivity and area coverage are investigated. On the one hand, these two metrics are very important, especially for applications where achieving the best area-coverage and maintaining network connectivity represent an essential requirement. On the other hand, energy is another equally noteworthy constraint that should be taken into account. In fact, being a crucial resource for all mobile devices and especially for UAVs, the energy becomes vital to ensure the network lifetime and mission success. As far as we know, Alpha-based mobility model is the first to ever consider a combination of these three metrics within the same decision-making criterion. A distributed scheme is adopted, where each UAV determines locally its future movement based on the information it receives from its neighbors. Moreover, a novel fuzzy inference system is implemented in order to compute the values of a followship weighting parameter, named Alpha. This latter is used to choose the most suitable neighboring UAV to follow. To validate the proposed mobility model, rigorous testing has been accomplished, through simulation work. Compared to Random-based and Forces-based mobility models, the Alpha-based mobility model achieves good coverage rate while maintaining connectivity.     

Techno-economical optimization of hybrid pv/wind/battery system using Neuro-Fuzzy

High cost of renewable energy systems has led to its slow adoption in many countries. Hence, it is vital to select an appropriate size of the system in order to reduce the cost and excess energy produced as well as to maximize the available resources. The sizing of hybrid system must satisfy the LPSP (Loss of Power Supply Probability) which determines the ability of the system to meet the load requirements. Once the lowest configurations are determined, the cost of the system must then be taken into consideration to determine the system with the lowest cost. The optimization methodology proposed in this paper uses the ANFIS (Adaptive Neuro-Fuzzy Inference System) to model the PV and wind sources. The algorithm developed is compared to HOMER (Hybrid Optimization Model for Electric Renewables) and HOGA (Hybrid Optimization by Genetic Algorithms) software and the results demonstrate an accuracy of 96% for PV and wind. The optimized system is simulated in PSCAD/EMTDC and the results show that low excess energy is achieved. The optimized system is also able to supply power to the load without any renewable sources for a longer period, while conforming to the desired LPSP.     

Behaviour of CI engine performance,combustion and exhaust emission with neem biodiesel at varied fuel injection rates

Motorisation and fast depletion of fossil fuel reserves and issues like global warming have led the researchers all over to look for substitute fuels. Biodiesel resulting from vegetable oil is being used around the globe to lessen air pollution and reduce the necessity of diesel fuel. The current study covers the various aspects of N20 neem biodiesel with increased fuel injection pressure. The blends of N20 were tested with increased fuel injection pressure to examine the characteristics such as brake thermal efficiency, fuel consumption, emission and combustion parameters. Experimental results indicated that N20 with 240?bar has a closer performance to diesel, reduced exhaust emission and improved combustion parameters.     

铀矿山经济评价专家系统EVALUATOR的研制

本文通过铀矿山经济评价专家系统EVALUATOR的研制过程，讨论了专家系统的理论基础、推理机原理、知识库建造、解释机实现、领域知识获取、知识表示方法等，特别对本专家系统中应用的主观Bayes不精确推理方法作了较详细的探讨。     

基于BRICKS的车用柴油机曲轴扭振与减振分析

介绍AVL公司开发的发动机模拟软件BRICKS的功能和特点,针对某车用柴油机飞轮螺栓断裂问题,利用该软件对轴系进行了扭振与减振分析,并提出相应地改进措施,取得了预期的效果。     

信息引擎基础组件开发及应用

融合多种高新技术、运用ActiveX控件技术自主开发的信息引擎基础组件、综合处理音频／视频、文字／数据、静态／动态等信息各方面特征,从底层数据结构实现多种信息系统的无缝连接。它对信息管理、表达采用存储层、算法层、表达层体系结构,能满足各种用户多层次需求,特别便于用户根据需要二次开发。分析了基础组件开发的必要性、设计思想、功能特点,介绍了基于基础组件开发的含有GIS功能的可视化实时监控系统。     

教学游戏软件的设计与实现

电脑游戏开发是故事、艺术、音乐、声音效果、动画及程序设计技术的有机结合,以产生一种动态的、具有很强交互性的电子娱乐形式。本文以设计开发角色扮演游戏为目标,在此基础上提出新的探索,即寓教于乐的设计思想,着重从技术上讨论了角色扮演游戏的设计与实现。     

发电电焊机励磁调节器输入电压测量方法研究

给出了发电电焊机及其励磁调节控制部分设计原理,励磁调节控制部分的输入电压信号由弧焊逆变电源的整流滤波环节后的直流电压址取得。对有谐波时的发电机端电压平均值和有效值进行了分析计算,阐明了其差异。基于MATLAB仿真软件对励磁调节控制部分电压由Ux取得时发电电焊机的输出与常规AVR控制时发电电焊机的输出进行了仿真对比研究,表明这两种情况下发电电焊机输出的焊接电压和电流特性有较大差异。理论分析和仿真研究均表明,励磁调节控制部分的输入电压由Ux取得时发电电焊机系统具有更好的鲁棒性,焊接电弧稳定。     

基于MongoDB的HIAF Archive Engine设计与实现

强流重离子加速器装置（HIAF）的控制系统采用实验物理和工业控制系统（EPICS）架构,运行数据存储系统为HIAF运行中的运行数据、历史数据和静态参数提供稳定可靠的存储。针对当前EPICS架构下的数据存储工具仅支持关系型数据库的不足,开发非关系型数据库MongoDB接口,并利用MongoDB嵌套对象和多层级存储结构的特点优化存储表结构,实现波形、图像等非关系型数据的高效存储;为调束人员提供基于标志位PV（Flag PV）方式的加速器运行数据手动存储方案以提升历史数据检索效率及数据可用性;同时针对海量历史数据的存储需要,利用MongoDB Sharding搭建MongoDB分布式集群。