A design optimization tool of earth-to-air heat exchanger using a genetic algorithm

Advancement in genetic algorithm (GA) optimization tools for design applications, coupled with techniques of soft computing, have led to new possibilities in the way computers interact with the optimization process. In this paper, the concept of goal-oriented GA has been used to design a tool for evaluating and optimizing various aspects of earth-to-air heat exchanger behavior. A new optimization method based on GA is applied as a generative and search procedure to optimize the design of earth-to-air heat exchanger. The GA is used to generate possible design solutions, which are evaluated in terms of passive heating and cooling of building, using a detailed thermal analysis of non air-condition building environment The results from the simulations are subsequently used to further guide the GA search to find the high-energy solutions for optimized design parameters. The specific problem addressed in this study is the sizing of earth-to-air heat exchanger in a non air-conditioned residential building. The developed algorithm is suitable for the calculation of the outlet air temperature and therefore of the heating and cooling potential of the earth-to-air heat exchanger system. This methodology is applicable to a wide range of design optimization problems like choice of building such as green house, solar house, or heating and cooling of buildings by mechanical system.     

太阳能热水-采暖联合系统

目前在欧洲流行的太阳能联合系统,是将太阳能热水技术和建筑采暖技术相结合,以提供充足的生活热水和舒适的采暖环境,文章介绍了太阳能联合系统的特点和典型系统的运行原理,以及该技术在欧盟的应用概况.     

Antireflecting–passivating dielectric films on crystalline silicon solar cells for space applications

Antireflecting–passivating TiO₂–SiO₂ double layers on crystalline silicon (Si) were optimized and characterized for space solar cells applications. In the numeric optimization, the MgF₂–glass–adhesive–TiO₂–SiO₂–Si structure was considered. In order to fabricate the TiO₂–SiO₂ double layer, titanium films were deposited on Si wafers in a vacuum chamber, and then, the sample was annealed in oxygen at high temperatures. Glasses with evaporated MgF₂ thin films were bonded to the TiO₂–SiO₂–Si samples so as to obtain the complete structure. A gain of up to 23.5% in the maximum power is demonstrated for simulated c-Si solar cells using the optimized structure. Characterization of the TiO₂–SiO₂–Si structure using transmission electron microscopy (TEM) and X-ray reflectivity (XRR) as well as optical characterization are presented.     

基于空间六自由度机械臂的逆运动学数值解法

针对解析法只能用于特殊构型的机械臂且求解过程复杂、计算量大的问题,提出一种适用于大多数串联型机械臂的数值迭代逆运动学求解方法.利用该方法,求解自主研发的空间六自由度机械臂的运动学逆解,并通过仿真证明该方法的可靠性.     

量子通信技术在航天系统中的应用研究

较传统保密技术而言,量子通信技术在信息安全方面具有更大的优势,在军事通信领域具有广阔的应用前景。在简要介绍量子通信原理、研究进展的基础上,对量子通信技术在航天系统中的应用进行了初步设想,为推动量子通信技术在航天领域的应用提供参考。     

激光星际链路分析研究

作为星际光链路的空间激光通信可建立全天候、高机动性、高灵活性、高可靠信息平台.德国空间固体激光通信由两个光通信终端及各自的实验平台组成,可模拟卫星的相对运动和抖动.其一个终端采用1064nm YAG激光器,以650mbps码率传输数据.另一终端采用810nm半导体激光器,通信速率是10mbps.     

欧洲自动转移飞行器

分析了欧洲自动转移飞行器。首先介绍其研制概况、货运能力,然后分析其总体结构和飞行任务,探讨其发展潜力、总结其设计特色,最后展望其未来应用。     

CZ-2C火箭常规二级推进剂钝化过程分析

CZ-2C火箭发射SSO轨道卫星在星箭分离后其二级箭体轨道寿命很长,成为空间垃圾。为适应空间碎片减缓工作的需求,应该对二级箭体内剩余推进剂进行排放处理。针对优选排放方案,分析排放过程的工作情况和参数,并参照遥测数据对分析结果进行验证。     

天梯技术研究进展

天梯作为一种极具潜力的未来新概念航天运输系统,在航天领域越来越受到重视。对国内外在天梯技术方面的研究进展进行介绍,对天梯在航天运输系统领域的应用需求进行分析,描述天梯系统的基本组成和基本原理,最后针对未来大规模进入空间需求,给出总体参数指标。研究内容为后续开展天梯的深入研究提供参考。