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11.
研究了碳源、氮源、无机盐、金属离子等培养基组成和初始pH、通风量、温度等发酵条件对短杆菌(Bre vibacteriumspWX 10)产酶的影响,通过正校试验优化得到的产酶培养基组成及发酵条件:蔗糖1%,NaCl2 5%,牛肉膏0 05%,NaNO30 05%,pH7 5,500mL三角瓶装培养基50mL,30℃于220r/min旋转式摇床上培养72h.在该培养条件下WX 10产酶量是原培养条件下的1 85倍.  相似文献   
12.
There are many models that require the estimation of a set of ordered parameters. For example, multivariate analysis of variance often is formulated as testing for the equality of the parameters versus an ordered alternative. This problem, referred to as isotonic inference, constrained inference, or isotonic regression, has led to the development of general solutions, not often easy to apply in special models. In this expository paper, we study the special case of a separable convex quadratic programming problem for which the optimality conditions lead to a readily solved linear complementarity problem in the Lagrange multipliers, and subsequently to an equivalent linear programming problem, whose solution can be used to recover the solution of the original isotonic problem. The method can be applied to estimating ordered correlations, ordered binomial probabilities, ordered Poisson parameters, ordered exponential scale parameters, or ordered risk differences.  相似文献   
13.
In order to assess the effectiveness of government programs designed to reduce disparities in the health care minority groups receive relative to the majority white population, a proper statistical measure should be used. This article proposes a measure of and its accompanying graph, which is readily interpretable and is not affected by the number of minority subgroups examined.  相似文献   
14.
In this paper, we deal with a discrete-time multiserver retrial queue with finite population. Firstly, we study the Markov chain at the epochs immediately after slot boundaries making emphasis on the computation of its steady-state distribution. Then, the main performance measures are investigated. Besides, we simulate the waiting time of a customer in the retrial group under three different queueing policies. Some numerical examples are given to illustrate the analysis.  相似文献   
15.
It is shown that when a parameter lying in a sufficiently small interval is to be estimated in a family of uniform distributions, a two point prior is least favourable under squared error loss. The unique Bayes estimator with respect to this prior is minimax. The Γ-minimax estimator is derived for sets Γ of priors consisting of all priors that give fixed probabilities to two specified subintervals of the parameter space if a two point prior is least favourable in Γ.  相似文献   
16.
Summary We consider a lotL formed byN apparently similar unitsW 1,…,W N, where each of theW i may come from one of two different populationsP 1 andP 2;T 1,…,T N denote the corresponding lifetimes. The units fromP i undergo a failure of kindi and their survival function isS i (t). We assume that the failure rate function are known and that the units fromP 1 are ?substandard?: λ 1 (t)≥λ 2 (t), ∀t≥0. We want to putW 1,…,W N under a pre-operational test (burn-in test) in order to eliminate at least a great part of the substandard units and we face the problem of obtaining a rule for stopping the test under the assumption that, with the failure of a unit, it is possible to recognize the population from which the unit comes. Such a problem will be formalized as an optimal stopping problem for a suitably defined Markov process. Our study shall evidentiate some fundamental aspects of the problem and the role of the prior distribution of the (random) numberM 0 of those units inL coming fromP 1 (substandard). The latter distribution has a great influence on the form of the solution. This research was supported by the C.N.R. Project ?Statistica Bayesiana e Simulazione in Affidalità e Modellistica Biologica?.  相似文献   
17.
Federal legislation regarding health care in the U.S. has increased rapidly in the past few years. A major law with potential far-reaching effects was enacted as a result of increasing legislation and rising health care costs. This law,The National Health Planning and Resources Development Act,has created a network of over 200 local, mostly nongovernment units, called health systems agencies. These agencies are responsible for areawide health planning, plan implementation, review and approval of federal health care expenditures for local programs, and facilities review. They will affect health and mental health programs at the local level. The article is directed to local health and mental health care providers who will, of necessity, deal directly with the local HSA's.  相似文献   
18.
程代伟 《科学咨询》2003,(17):27-27
准确的基础资料是系统运行的前提.在ERP系统的使用中,基础资料一定要保证正确性、完整性和唯一性.BOM是系统最重要的基础资料之一,它的准确与否将直接影响MRP计划、生产投料、生产领料、成本计算等业务的正确性.为准确录入BOM的基础数据,在长期工作实践中,本人摸索出一些技巧,不敢私自独用,便拿出来与大家分享.  相似文献   
19.
经监测,永泰县城区大气污染物主要为PMl0、PM2.5、O3,影响O3的因素主要有汽车尾气排放、日照,PMl0、PM2.5浓度大小除与车流量、烟花爆竹燃放相关外,还与降水、风速等气象因素密切关联。针对这些影响因素,该文提出了相应的防治措施。  相似文献   
20.
In analyzing data from unreplicated factorial designs, the half-normal probability plot is commonly used to screen for the ‘vital few’ effects. Recently, many formal methods have been proposed to overcome the subjectivity of this plot. Lawson (1998) (hereafter denoted as LGB) suggested a hybrid method based on the half-normal probability plot, which is a blend of Lenth (1989) and Loh (1992) method. The method consists of fitting a simple least squares line to the inliers, which are determined by the Lenth method. The effects exceeding the prediction limits based on the fitted line are candidates for the vital few effects. To improve the accuracy of partitioning the effects into inliers and outliers, we propose a modified LGB method (hereafter denoted as the Mod_LGB method), in which more outliers can be classified by using both the Carling’s modification of the box plot (Carling, 2000) and Lenth method. If no outlier exists or there is a wide range in the inliers as determined by the Lenth method, more outliers can be found by the Carling method. A simulation study is conducted in unreplicated 24 designs with the number of active effects ranging from 1 to 6 to compare the efficiency of the Lenth method, original LGB methods, and the proposed modified version of the LGB method.  相似文献   
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