管理信息系统中随机制表研究

随机制表以一个数据库为基础,随机制作一个或多个二维表格以供输出。制表的核心部分是对表头进行编码,其规律是从左到右,从上到下,第一层用一个字母,第二层用两个字母,依次类推。     

Probability models of chance fluctuations in spectra of astronomical sources with applications to X-ray absorption lines

The search for faint emission or absorption lines in astronomical spectra has received considerable attention in recent years, especially in the X-ray wavelength range. These features usually appear as a deficit or excess of counts in a single-resolution element of the detector, and as such they are referred to as unresolved fluctuations. The general problem under investigation is the probability of occurrence of chance fluctuations. A quantitative answer is necessary to determine whether detected fluctuations are a real (astronomical, in this case) signal, or if they can be attributed to chance. This application note provides a new comprehensive method to answer this question as function of the instrument's resolution, the wavelength coverage of the spectrum, the number of fluctuations of interest, and the confidence level chosen. The method is based on the binomial distribution and addresses also the probability of multiple simultaneous fluctuations. A critical aspect of the model is the a priori knowledge of the location of possible fluctuations, which significantly affects the probability of detection. In fact, a wider wavelength range for the ‘blind’ search of possible fluctuations results in a larger number of ‘tries’ for the detection of a fluctuation, lowering the overall significance of a specific feature. The method is illustrated with a case study and examples using X-ray data.     

Institutional Activism: Seeking Customary Forest Rights Recognition from Within the Indonesian State

This article aims to explain why the adat movement activists in Indonesia could expand their campaigns for state recognition of adat community rights to activities from within the state apparatus. We argue that three combined processes have contributed to the conjuncture that made institutional activism possible: the preparation of the 2014 national election offered activists opportunities to influence the government agenda; the emergence of a conscious strategy for conducting institutional activism; and the coalitions between some key state officials and the movement’s actors. This article also analyses the problems that institutional activists faced, in particular resistance from influential actors at various government units who were not sympathetic to the adat movement’s agenda. Therefore, the impact of this activism on policy changes so far remains limited. The authors’ personal involvement in this case of institutional activism to promote customary forest provided access to the information for this article.     

天竺山旅游资源开发的整体思路与对策

根据当前旅游业发展特点和趋势 ,从森林旅游资源开发角度出发 ,分析了厦门天竺山森林旅游资源的现状和特点 ,提出景区开发的指导思想及宏观思路 ,并就开发中应注意的几个问题及政策建议进行了探讨。     

货币政策操作规则的转变及启示

美联储在货币政策操作规则上放弃了传统的“相机抉择”及“单一规则”,转而采取兼顾可信度和灵活度的“泰勒规则”。我国应采取既对政策工具有规则约束 ,又对当前或预测的经济状况作出反应的积极货币政策操作规则     

Simulation of Constrained Variables in Engineering Risk Analyses

The problem of sampling random variables with overlapping pdfs subject to inequality constraints is addressed. Often, the values of physical variables in an engineering model are interrelated. This mutual dependence imposes inequality constraints on the random variables representing these parameters. Ignoring the interdependencies and sampling the variables independently can lead to inconsistency/bias. We propose an algorithm to generate samples of constrained random variables that are characterized by typical continuous probability distributions and are subject to different kinds of inequality constraints. The sampling procedure is illustrated for various representative cases and one realistic application to simulation of structural natural frequencies.     

Asymptotic random extremal ratio and product based on generalized order statistics and its dual

The extremal ratio has been used in several fields, most notably in industrial quality control, life testing, small-area variation analysis, and the classical heterogeneity of variance situation. In many biological, agricultural, military activity problems and in some quality control problems, it is almost impossible to have a fixed sample size, because some observations are always lost for various reasons. Therefore, the sample size itself is considered frequently to be an random variable (rv). Generalized order statistics (GOS) have been introduced as a unifying theme for several models of ascendingly ordered rvs. The concept of dual generalized order statistics (DGOS) is introduced to enable a common approach to descendingly ordered rvs. In this article, the limit dfs are obtained for the extremal ratio and product with random indices under non random normalization based on GOS and DGOS. Moreover, this article considers the conditions under which the cases of random and non random indices give the same asymptotic results. Some illustrative examples are obtained, which lend further support to our theoretical results.     

Population correlation matrices for sampling experiments

A procedure is given for generating correlation matrices which can be used as population correlation matrices for sampling experiments. The algorithm specifies the eigenvalues and randomly selects a correlation matrix from the class of all correlation matrices which possess these same eigenvalues. It is possible to obtain a set of correlation matrices which are indexed by the degree of interdependence among the variables by parameterizing the eigenvalues with a single parameter. An example is the case in which the eigenvalues form a geometric progression. Examples are given and an application to the problem of stopping rules in stepwise regression is discussed. Other applications are also briefly discussed.     

随机供货下销售商最优订购决策

在实际生产生活中,存在着由于产品本身生产的随机性和一些外部因素导致生产商供货不确定的问题。在此背景下,本文研究单周期供货不确定情况下销售商的最优订购决策。从理论上分析了最终到货量为订购量与扰动变量加和的情况下,销售商存在最优订购量,按照新的策略订购可以使销售商利润最大化,并最大程度地消除由于订货不足或者订货过量所带来的负面效应。     

The matching, birthday and the strong birthday problem: a contemporary review

This article provides a contemporary exposition at a moderately quantitative level of the distribution theory associated with the matching and the birthday problems. A large number of examples, many not well known, are provided to help a reader have a feeling for these questions at an intuitive level.