Unusual Photon Energy Dependence of the Cooper Pair Breaking Rate in YBa2Cu3O7?δ Epitaxial Thin Films

The transient photoimpedance response of epitaxial YBa₂Cu₃O_7– thin films has been studied using 100 fs Ti:Sapphire laser pulse excitation. Both temperature and photon energy dependence of the fast optical response signal (whose temperature dependence can be explained by a kinetic inductance model involving Cooper pair breaking) were studied. The pair breaking rate is strongly photon energy-dependent, with a resonance around 1.5 eV with a width of only 100 meV, which is very surprising given the strong electron correlation in this metallic system and may be explained in terms of the stripe phase model.YGZ is on leave from     

Smart,connected open architecture product: an IT-driven co-creation paradigm with lifecycle personalization concerns

Nowadays, the emphasis on manufacturing has shifted from a manufacturer-dominating to a customer-centric manner by actively involving users into the co-creation process to realise individual satisfaction. In such era, the rapid development of information and communication technology (e.g. wireless sensor network, and cyber-physical systems) enables a promising market of IT-driven product, i.e. smart, connected product, and also changes the way of user–manufacturer interaction in the product development process. However, to the best of authors’ knowledge, co-creation manner in such context is scarcely reported. Meanwhile, there is a lack of any paradigms given to enable such product open innovation along the lifecycle for personalisation concerns. Aiming to fill this gap, this paper, as an explorative research, proposes a new product development paradigm, i.e. smart, connected open architecture product (SCOAP). It follows the adaptable design principles for product extendibility and lifecycle consideration. Moreover, it enlarges the scope of existing open architecture product by involving IT-driven innovation consideration as well. Hence, the definitions, characteristics, evaluation criteria, development method, and lifecycle co-creation context of SCOAP are presented in details. To make it more concrete, a demo project of a smart, connected open architecture bicycle is given at last.     

一种带引射器和经济器的CO2跨临界制冷系统

在蒸发温度较低的工况下,CO₂跨临界循环高低压差过大,运行效率下降。针对CO₂跨临界循环特性,提出了一种带引射器和经济器的CO₂跨临界制冷系统,通过引射器部分回收工质膨胀功减小能量损失,可增加制冷量;合理设计CO₂压缩机和中间补气孔,采用经济器进行中间补气可减少系统压缩过程的能量损失。构建了热力学模型,研究表明该系统在较低蒸发温度工况下,相比于基础CO₂跨临界制冷系统系统性能可提升40%左右,其中压缩机排气温度可降低40℃左右,有利于系统稳定运行。同时对准二级压缩过程中分段效率计算问题提出近似公式,在一定范围内相比于传统计算方式误差从5%降低至2%。     

The chemistry and medicinal uses of the underutilized Indian fruit tree Garcinia indica Choisy (kokum): A review

Garcinia indica Choisy Syn Brindonia indica, commonly known as kokum and belonging to Guttiferae family, is a plant native to certain regions of India. The trees yield fruits annually in the summer season during the months of March to May. The fruits are green when raw and red to dark purple when fully ripe. They are used to prepare juice, pickles and as acidulant in curries. In the traditional Indian system of medicine the Ayurveda and in various folk systems of medicine, the fruit rinds and leaves are used to treat various inflammatory ailments, rheumatic pain and bowel complaints. The kokum butter prepared from the seed is of both commercial and medicinal use. Chemical studies have shown that the rind contains protein, tannin, pectin, sugars, fat, organic acids like (−)-hydroxycitric acid, hydroxycitric acid lactone and citric acid; the anthocyanins, cyanidin-3-glucoside and cyanidin-3-sambubioside; and the polyisoprenylated phenolics garcinol and isogarcinol. Preclinical studies have shown that kokum or and some of its phytochemicals possess antibacterial, antifungal, anti-ulcerogenic, cardioprotective, anticancer, chemopreventive, free radical scavenging, antioxidant and anti-obesity effects. The present paper reviews the nutritional value, the phytochemical compounds, traditional uses and validated pharmacological properties of kokum.     

基于PSCAD4.2软件的电力系统距离保护仿真分析

分析了输电线路距离保护的基本原理,并基于PSCAD4.2软件搭建了电力系统距离保护仿真模型,设置了输电线路可能发生的接地故障和相间故障,得出不同故障类型下输电线路的电压、电流以及其他量的变化规律的波形,仿真结果表明,利用该软件建立的模型能够准确反映距离保护的作用机理,即距离保护装置能够快速响应故障信号并动作于断路器,实现输电线路的保护。     

A sensitivity-based approach for studying stability impact of distributed generation

In this paper we investigate the impact of distributed generation (DG) on system stability using the trajectory sensitivity approach and identify the machines that are vulnerable to the addition of DG. We also vary the penetration level of DG and evaluate the influence of the DG modeling. Sensitivity formulation for the differential-algebraic equation model is presented through a single-machine infinite-bus (SMIB) example. The methodology can be extended to study the influence of parameters other than the clearing time, such as series line reactance.     

煤层气田远控智能排采系统的开发与应用

山西临汾马必东区块属于高阶煤储层,需要建立以井底流压为主、套压为辅的智能排采控制流程,保证连续、渐变、稳定、高效的排采管控,但目前采用现场就地调控参数,不仅劳动强度大,而且调节结果滞后,影响稳定生产。本着精细研究、精准管控的原则,开发了基于组态软件的自动化智能排采系统,该系统包含自动化智能排采、生产参数采集、实时数据报警、远程启停井四个子系统,不仅能实现远程智能排采调节、生产数据监控,还能实现生产组织扁平化、信息传输网络化、技术管理数字化和人力资源最优化,为智慧气田智能排采系统的建设与推广提供了借鉴。     

需求响应下基于近似动态规划的气电联合系统经济调度

气电联合系统协同运行能显著提高能源利用效率,其运行优化得到了广泛关注。文章建立了考虑需求响应（demand response,DR）的气电联合系统经济调度模型,并提出了基于近似动态规划（approximate dynamic programming, ADP）算法的联合系统经济调度策略。首先,采用粒子群（particle swarm optimization ,PSO）优化算法对用户侧的负荷曲线进行优化,从而最小化用户补偿费用和峰谷差率;随后建立线性化的气电联合系统运行模型,借助ADP算法求解。以Grave 6节点电力系统和14节点天然气网络进行仿真分析。仿真结果验证了所提模型和求解算法的有效性,考虑供需两侧的气电联合优化能提高能源利用效率。