关于蝗虫类种属比率的研究

:(1)当代蝗虫类的种属比率 ,单型属、寡型属和多型属的百分比同鸟类非常接近 ,即单型属高居首位 ,寡型属次之 ,多型属沦于末位。 (2)蝗虫类分布在中国的有217属 ,其中单型属、寡型属和多型属的百分比同全世界的情况完全相反 ,多型属最多 ,寡型属居中 ,单型属最少。(3)中国的蝗虫类单型属同近缘属的主要区别特征标准较为一致 ,属的地位相对稳定     

影响采掘机械截割块率和粉尘的因素分析

通过对采掘机械截割的块率和粉尘有关参数关系的分析，给出了各因素地截割块率和粉尘的影响，探讨了提高块率降低截割粉尘的途径。     

精馏塔控制实质的探讨

本文从精馏操作原理出发,得出精馏塔控制的实质是在塔板结构与塔板数不变的条件下,改变操作条件,以使精馏塔在受到干扰后仍能维持原来的塔顶或塔底产品组成。应用这些基本关系,推导出操作变量的近似计算公式。这些关系式经过计算验证,误差在允许范围内,在控制中是可以应用的。     

超长十六进制整数到十进制整数的转换

本文利用数制转换原理，构造了超长十六进制整数到十进制整数变换的变换矩阵（Ｔ）１６１０；进一步利用整数的进位原理推出了超长十六进制整数到十进制整数间的码－码变换公式，利用本变换最大可得到４０位十进制整数。     

论非抛物点曲面的平行曲面

研究不含抛物点的曲面的平行曲面的一些重要性质，找出了曲面与其平行曲面的关系．     

纱条混纺比对电容式条干均匀度仪测试信号的影响

根据电容式均匀度仪的原理,当混纺纱条在电容式传感器中的充满度很小时,提出成分、纤维和空气三者组成串联或并联介质的分析方法。这两种分析方法均可推得电容变化量与纱条混纺比之间的线性关系。但是,串联方法的结果与实验结果存在明显差异,并联方法则与实际情况较为吻合,因此,对于混纺纱条,当成分纤维介电常数的差异及混纺不匀较大时,测得的不匀率数值将大于纱条的实际条干不匀率。     

对弗里特曼联合强度理论的扩展

简要叙述弗里特曼联合强度理论，然后对该理论作了扩展．认为现今引用该理论，不论是在材料力学的教学上还是在工程实践上，都是可行的和有益的．     

刀口滤波实验研究

对在非相干光照明条件下的刀口滤波实现现象进行了分析，并用部分相干光成像理论解释了实验中产生体视像和反转像的原因。     

ON-LINE PREEMPTIVE SCHEDULING ON UNIFORM MACHINES

1 IntroductionWe consider the problem of sChedallng a 1ist (J1, J2,' .) of on-line jobs preemPtive1y onm unifornily related machines. In suCh a setting, the jobs arrive one by one. Job Jj becomesknown (with its etistence and its processing time Pj ) only When job Jj--1 has already beenscheduled, which gives rise to the name online schedallng. Job processing can be preemPtive,i.e., the processing of any job can be interruPted and resumed later. The machines are paralleI,which allows any …     

On the Difficulty of Measuring Forecasting Skill in Financial Markets

The use of correlation between forecasts and actual returns is commonplace in the literature, often used as a measurement of investors' skill. A prominent application of this is the concept of the information coefficient (IC). Not only can the IC be used as a tool to rate analysts and fund managers but it also represents an important parameter in the asset allocation and portfolio construction process. Nevertheless, a theoretical understanding of it has typically been limited to the partial equilibrium context where the investing activities of each agent have no effect on other market participants. In this paper we show that this can be an undesirable oversimplification and we demonstrate plausible circumstances in which conventional empirical measurements of IC can be highly misleading. We suggest that improved understanding of IC in a general equilibrium setting can lead to refined portfolio decision making ex ante and more informative analysis of performance ex post. Copyright © 2015 John Wiley & Sons, Ltd.