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Meanwhile, it could be seen that there does not exist a confidence interval with width less than 0.5 because of the property of Poisson distribution. Based on these conditions, the author mainly carried out research into two aspects of this problem as follows. Firstly, by numerical and theoretical analysis, the author compares some existent confidence intervals, for example,"exact" confidence interval, Wald confidence interval and Bayesian confidence interval, and finds some deficiencies points of the confidence intervals, whose modification version has been proposed .Also, several better confidence intervals such asare also presented .Secondly, for given confidence coefficient and interval width, the author constructs a class of asymptotical two-stage interval estimate procedures. At the same time, under varies restriction of confidence coefflcientent interval width, the optional sample size of the first stage has been computed by numerical computation. The numerical computation shows that the method considered in this dissertation have good properties and applied value.

同时，由于Poisson分布的特性，我们知道不存在其参数区间长度小于0.5的置信区间，基于这些情况，我们主要展开了以下两个方面的研究：一是利用数值计算分析与理论分析的方法对现有的若干置信区间如"精确"置信区间，Wald置信区间，Bayes置信区间等进行分析比较，发现了一些缺陷，针对这些缺陷，我们进行适当的修正，并得到几种性质较好的置信区间如：修正大样本区间Jeffreys原则下置信区间二是针对已给定的置信系数与区间长度，我们提出了一种渐近的两阶段区间估计程序，并利用数值计算的方法，在各种置信系数与区间长度限定下，算出了最优的第一阶段观测次数，大量数据表明，本文考虑的方法性态良好，具有应用价值。

However, class struggle will continue to exist within certain limits for a long time to come.

完成统一祖国的大业是包括台湾同胞在内的全中国人民的神圣职责。

There exist diffrenent weak interactions in the clathrate complexation.

得到的笼形包合物中存在不同的弱相互作用。

Firstly, pottery originates in the imitation to their own body of our ancestors, that is, the evolution of clay model;secondly, the evolution of clay into pottery is a long way to go. During this process, a so-called "mud browser" time should exist.

一是陶器的起源是来自于原始先民对自身形体的模仿，及其这种泥塑的器型演变；二是由泥塑到陶器的演化是相当漫长的，在这个过程中应该存在一个所谓的"泥器"时代。

The range of different climatic conditions that exist in the world.

全球各种气候的范围。

Conceptually such equations exist, however, they are not available in closed form.

从而验证POD方法在降维问题上的有效性和可行性。

When the sodium lauryl sulfate and p-octyl polyethylene glycol phenyl ether is used and its level in 3% and 6: 4 ratio, the polymerization process has the lowest coagulum and the highest monomer conversion. Higher reaction temperature and more level hydroxyl value lead to more coagulum, the latter also lead to larger particle size. The acid value has larger influence on viscosity and coagulum, there exist a best range. The emulsion particle size is larger for its hydrophilicity, most of its particles are connected together.

在含较高亲水单体的乳液聚合体系中，难以制得稳定的预乳化液，不能采用工业生产中常用的预乳化工艺，而只能采用混合单体直接滴加的方法；由于单体混合物的亲水亲油值较高，用阴离子型乳化剂十二烷基硫酸钠和非离子型乳化剂聚乙二醇辛基苯基醚混合，用量为单体总量的3％，且比例在6：4时，乳液聚合时具有最低的凝聚物含量和最高的单体转化率；乳液聚合反应温度升高，可以提高单体转化率，增加反应速度，但凝聚率相应提高；随着羟基单体含量的增加，聚合过程中凝聚率增加，聚合物乳胶粒平均直径增加；羧基单体有一个最佳的用量（2.6％），过高或过低凝聚率均提高；羧基含量对乳液的粘度有较大的影响，当羧基含量较低时，羧基含量增加，乳液粘度增加明显；含羟基乳液粒子由于含亲水基团较多，使得乳胶粒径增大，乳胶粒子大多数互相凝聚在一起，处于凝聚态。

In theindustry field, coal mines exist the most major hazards and the greatest risks.

在工业生产领域，煤矿重大灾害危险源最多、安全隐患最大。

By splicing in genes from other bugs, the company was able to engineer synthetic metabolic pathways—ones that do not exist in nature—that enable the bacteria to produce isoprene from the sugars found in plant materials such as sugar cane, corn cobs and switchgrass, a tall-growing variety native to North America.

Genecor的科学家们将其它细菌的基因拼接到大肠杆菌上，从而在大肠杆菌上制造出一种自然界中不存在的代谢物合成途径。它使细菌能从植物材料中的糖分生产出异戊二烯——这些含有糖类的植物包括甘蔗、玉米芯，还有原产于北美洲的高个儿品种柳枝稷。

Morphological conversion from spiralto coccoid forms occurred when HP was cultured with selenium and most of coccoid forms had fragmentary flagella and pilus; the effection of selenium to activity of urease, catalase, alkaline phosphatase is not exist or not evidence; selenium enable pET32a-vacA-E.coli BL21 which can express VacA produce yellow lipochrome, and the color become deeper with increasing of concentration of selenium; selenium can decrease expression of recombined VacA by restrain the growth of pET32a-vacA-E.coli,but can not influence activity and gene sequence of VacA; selenium can enhance the suppression effect of recombined VacA for gastric cancer cell, depress the index of cell multiplication and the forming rate of colony, decrease the number of cell in S period, increase total of cell in G period; After purified, the recombined VacA can be identified by VacA antibody.

体外实验结果表明：一定浓度的硒作用HP后，HP菌落数量随着硒浓度的增加而减少，菌落颜色由灰白色变为砖红色，溶血现象随硒浓度的增加和作用时间的延长而逐渐消失，HP的形态由弯曲形变为球形或椭圆形，鞭毛及菌毛出现脱落现象；硒对尿素酶、过氧化氢酶、碱性磷酸酶活性无影响或影响不明显；一定浓度的硒能使表达VacA的pET32a-vacA-E.coli BL21工程菌产生脂溶性砖红色色素，颜色随硒浓度增加而加深；一定浓度的硒通过抑制pET32a-vacA-E.coli BL21工程菌的生长，减少重组VacA表达量，但不影响其空泡毒活性及编码基因序列；纯化后的VacA重组蛋白可被VacA抗体识别，具有良好的抗原性。

Objective:To compare the response control and attention of Schizophrenic patients with that of the healthy controls by Integrated Visual and Auditorycontinuous performance test. To quantitate the impairment of cognitive function in patients, and to explore the relationship between cognitive function and the severity of the disorder.

目的：探讨精神分裂症病人在IVA持续操作测试中的反应控制能力、注意力等，并与健康人进行比较，从而量化精神分裂症病人的认知功能损害，并进一步探讨其认知功能与疾病严重程度的关系。

Main effective factors including subcooling degree, mechanical vibration, gas hydrate reformation, environment temperature, noncondensing gas and surfactant are analyzed.

指出过冷度、机械振动、重复生成水合物、环境温度、不凝性气体、添加剂是影响气体水合物生成的主要因素，还对R152a水合物的放冷进行了实验研究。