考虑新能源发电与储能装置接入的智能电网转供能力分析

可再生能源发电和新型储能系统接入电网后使得N 1重构路径的选择更为复杂,为解决此背景下智能电网转供能力的计算问题,在对二者时变运行特性分析的基础上,提出基于智能电网转供能力指标体系的N 1恢复模型,通过对转供能力指标计算公式线性化处理,并结合基于拓扑模型简化的人工智能(artificial intelligence,AI)优化算法,利用优化调整电网、可再生能源发电、新型储能系统的运行方式,实现电网N 1后转供能力最大。最后,以某实际典型电网为例,分析可再生能源发电和新型储能系统接入电网对提升系统应对N 1故障能力和实现负荷有效转移的作用,验证了转供能力指标对于定量描述智能电网自愈特性的有效性。     

洪水预报系统中实时校正模型的优选方法

针对实时洪水预报系统中实时校正模型存在一定的适用范围却又难以在线优选的问题,首先分析了自适应滤波模型、马斯京根矩阵模型和反馈模拟模型3种传统实时校正模型的原理与适用性,并编制算法流程图,为代码编程提供依据。其次,提出了一种实时校正模型的优选方法,适用于大流域多校正断面的实时洪水预报系统,可以为各断面在线优选出最优的实时校正模型。在WDS9002三峡实时洪水预报系统中的应用结果表明:优选方法在校正成功率和各项精度评价指标统计上出现最优的频次高于传统实时校正模型,且很少出现指标统计最差的情况;另外,优选方法有     

高功率横流CO2激光横模随时间变化的测量

用激光光束分析仪实时在线测量了一台连续运转的高功率横流CO2激光器的激光横模,获得了较为完整的激光横模随时间的变化关系.测量结果表明,激光输出由两个分离的、非对称的高阶横模叠加组成("双模"),两横模中心相距约8 mm.形成"双模"的原因是串接式谐振腔的前腔和后腔两者的中心轴线不重合以及阴极铜管形变.横模随激光器运行时间的延长而逐步蜕化,呈更高阶和复杂化趋向.初步分析表明,横模的时间变化主要与激光器连续运转过程中腔内气体组分发生的变化有关.     

Cooperative load-balancing strategy based on N-hops routing algorithm of ad hoc network in heterogeneous overlapping networks

A major challenge of the heterogeneous wireless networks is how to jointly utilize the resources of different radio access technologies in an efficient manner. In this paper, system performance, such as the block probability and throughput, was investigated in communication hot spots overlapped by heterogeneous networks: cellular, WLAN, and WiMax networks. Two cooperative load-balancing strategies based on hops-limited routing algorithm of ad hoc network are proposed in order to raise the resource utilization of the whole overlapping heterogeneous networks. They both firstly make a decision whether to admit a new call or not based on common radio resource management strategies, and in overloaded condition, select certain traffic to transfer into targeted BS/AP according to minimum price strategy or minimum load BS/AP and nearest traffic strategy, which take into account these factors such as load index, number of hops, traffic prediction, cost, etc. An analytical model is used to compute the call block probability and throughput performance for two different traffic models. Simulation results show that the proposed load-balancing strategies can distribute traffics to the whole heterogeneous wireless networks, decrease the call block probability, improve system throughputs efficiently, and obviously outperform HM-MACA and HS-TC load-balancing strategies.     

荧光灯条纹不稳定性的实验研究

本文对50Hz低频工作的荧光灯中的条纹不稳定性进行了一系列实验研究。结果表明,在实验条件下,荧光灯中的条纹不稳定性与阴极区的扰动无关。条纹不稳定性的性质仅与灯管的冷端温度有关。     

延迟采收及不同酿造工艺对北国红山葡萄干红酒单宁含量影响

采用Folin-Denis法测定延迟采收及3种酿造工艺对北国红山葡萄干红酒单宁含量的影响。结果表明,利用3种酿造工艺均能有效浸出正常采收和延迟采收的北国红山葡萄中的单宁,延迟采收北国红酿制的干红酒单宁含量显著高于正常采收（P＜0.05）,采用工艺二酿制的北国红干红酒单宁含量显著高于工艺一和工艺三（P＜0.05）,且随着陈酿的进行,北国红干红酒的单宁含量显著低于发酵刚结束（P＜0.05）。正常采收和延迟采收的北国红利用3种酿造工艺酿制的干红酒单宁含量分别为0.92 g/L、1.17 g/L、1.10 g/L、1.46 g/L、1.52 g/L、1.45 g/L,其中延迟采收的北国红采用工艺二酿制的干酒单宁含量为1.52 g/L,柔顺指数为5.3,显著高于其他处理（P＜0.05）。     

海洋多肽的提取纯化及生物活性研究进展

海洋生物是人类重要的食物来源，其中含有大量高质量的蛋白质。海洋多肽具有抗高血压、抗氧化、抗肿瘤等生物学功能，作为开发功能性食品和药品的来源具有巨大的潜力。本文介绍了近年来国内外利用化学水解法、酶水解法、微生物发酵法以及物理辅助提取法提取海洋多肽并采用色谱法、膜分离法将其分离纯化的相关技术，比较了它们之间的差异性，并对海洋多肽的血管紧张素转换酶（ACE）抑制活性、抗氧化活性和抗肿瘤活性等生物活性以及应用现状进行了综述。     

双向DC/DC变换器Boost模式下的建模及控制

非隔离式的交错并联双向DC/DC变换器在混合直流供电系统有着广泛的应用,采用两路交错并联的拓扑结构可以有效减小DC/DC变换器的输出电压和电流纹波。为了提高双向DC/DC变换器的动态性能和过载保护性能,本文基于超级电容的备用电源储能系统,以两路交错并联Buck/Boost变换器在Boost模式下的各个模态作为模型进行分析,详细介绍了各个模态的工作过程;在导出其原始大信号模型的基础上,采用小信号线性化的方法进一步推导出其交流小信号状态方程及其等效电路模型,并得到了传递函数。以此为依据设计优化控制器的补偿网络,提高了系统的稳定性和瞬态响应速度,最后进行实验验证,结果表明,双闭环的控制策略实现了恒压限流且可以快速响应,满足实际工程的应用需要。     

Proportional-fair energy-efficient radio resource allocation for OFDMA smallcell networks

This paper investigates the energy-efficient radio resource allocation problem of the uplink smallcell networks. Different from the existing literatures which focus on improving the energy efficiency (EE) or providing fairness measured by data rates, this paper aims to provide fairness guarantee in terms of EE and achieve EE-based proportional fairness among all users in smallcell networks. Specifically, EE-based global proportional fairness utility optimization problem is formulated, taking into account each user’s quality of service, and the cross-tier interference limitation to ensure the macrocell transmission. Instead of dealing with the problem in forms of sum of logarithms directly, the problem is transformed into a form of sum of ratios firstly. Then, a two-step scheme which solves the subchannel and power allocation separately is adopted, and the corresponding subchannel allocation algorithm and power allocation algorithm are devised, respectively. The subchannel allocation algorithm is heuristic, but can achieve close-to-optimal performance with much lower complexity. The power allocation scheme is optimal, and is derived based on a novel method which can solve the sum of ratios problems efficiently. Numerical results verify the effectiveness of the proposed algorithms, especially the capability of EE fairness provisioning. Specifically, it is suggested that the proposed algorithms can improve the fairness level among smallcell users by 150–400 % compared to the existing algorithms.     

IMB—Ⅱ智能化多功能动平衡测试仪的设计与研制

ＩＭＢ－Ⅱ智能化多功能平衡仪测试仪采用了四阶带通自动跟踪滤波器和微机闭环程控放大器作为前置电路,使其结构简单可靠,编制了多种测试软件,强化了该仪器的使用功能,给出了仪器的性能实验和联机实验结果。