Optimal purchasing process for electricity and renewable energy credits with price and demand uncertainty

This paper optimizes the electricity and renewable energy credit (REC) purchasing process for energy distribution. Electricity is traded in deregulated time-sequential markets at fluctuating prices. Optimal electricity purchasing under price and demand uncertainty is a challenging task for electricity distributors, and the recently implemented renewable portfolio standards (RPS) further complicate the purchasing process. Government regulatory decisions concerning the RPS require distributors to purchase corresponding certificates, namely RECs, equivalent to a certain percentage of their electricity sales. This paper formulates and optimizes the joint purchasing process for electricity and RECs. It also analyzes the effect of RPS policy on electricity distributors.     

时标上二阶中立型时滞动力方程的振动性

借助时间尺度的有关理论，运用 Riccati 变换技巧，给出时间尺度上二阶非线性中立型时滞动力方程的新的振动准则。推广并改进时标上二阶非线性时滞动力方程振动性的一些结果。     

一种非线性调频波形优化设计算法

将遗传算法与动态优选法相结合，构成了一种新的算法，该算法能够有效抑制非线性调频信号通过匹配滤波器后产生的旁瓣，最后与数值法和动态优选法进行了比较。     

Study on Surface Optimization by Ion Beams

Preliminary tribo-mechanical properties of IBED filmsof GCr15 bearing steels have been studied in this paperalong with the comparison between IBED films and PVDfilms as well as non-implanted surface in wear resis-tance,micro-hardness,friction and surface morpholo-gy.Experiments gave a consistent picture and statedclearly that TIN films can really improve the tribo-me-chanical properties of materials and have practical usesin a certain sense.However,further theoretical and ex-perimental studies must be performed in respect thatthere are some defects on IBED films.     

含铌钛钢X—52连铸坯的高温延塑性

测试了溶点－７００℃温度区间含铌钛钢Ｘ－５２连铸坯的高温延塑性。根据断口形貌、组织以及钢中析出物等的变化情况分析了该钢的脆化机理。结果表明：在熔点－７００℃温度区间，Ｘ－５２钢存在２个脆性区，熔点－１３８０℃的第Ⅰ脆性区，９２５－８２５℃的第Ⅲ脆性区。细小的ＮｂＣＮ沿奥氏体晶界的动态析出是造成第Ⅲ区脆化的主要原因。可通过向钢中添加少量的钛，以降低晶界处细小的ＮｂＣＮ的析出量，防止先共析铁素体在奥氏     

动态规划的表格结构(Ⅱ)——关于网络中第一类最短路问题

本文讨论阶段数不确定、有限的情形。首先提出了三个有关代数结构的算法定理,使熟知的 Ford 算法,Gauss-Seidel 算法,Yen 第一、第二算法都是它们的特例。由于我们提出了 Yen 第三、第四算法,使得无回路网络中的问题,以及正网络中的 Dijkstra 算法的论证联成一线。而且,它们都可在前文(Ⅰ)所提出的表格上作数值计算。     

民间艺术中“脸”的形态表现

“脸”作为一个视觉语言，是人类始终关注的话题，自然形态中的脸只是作为个体存在的符号，是一种个体标记，人类为了满足宗教、战争和美化身心的种种需要，以符号为手段的脸的艺术造型形式是原始先民对人自身的存在形式不满足而进行的改造，新的形式从此就应运而生。脸作为一种符号，其最初的呈现状态是以纹样的方式展现出来的，被赋予了神秘的色彩，是人类实践经验、情感以及文化的交流与发展的延续。     

论民间法范式的研究方法

民间法研究方法主要通过其他人文和社会科学方法的借鉴而形成，包括主位方法、共时方法、动态方法，它们既可以适用结构主义又可以适用功能主义的立场。在研究民间法时须以三种方法联合使用，具体通过观察和“看”的方式进行。     

自准水平激光仪的动态应用

自准水平激光仪是利用激光作为准直光,广泛应用于地面平整、地面处理和渠道挖掘等方面。自准水平激光仪的激光信号与闭环控制系统的结合,实现地面的水平平整,它是自准水平激光仪的一种动态应用。     

Morphological characteristics of α-Al2O3 crystallites obtained direct1y from hydro /solvothermal solvents

The morphological characteristics of α-Al₂O₃ crystallites obtained directly from hydro/solv othermal solvents are reported and the formation mechanisms of corundum morphology are discussed from crystal growth and crystal chemistry principles. The crystal growth process is considered as a process of incorporation of growth units on the growth interfaces, and the crystal morphology is determined by the linkage of the coordinated polyhedra.