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1.
Associated with a parameterization for the three-parameter lognormal distribution, an algorithm was proposed by Komori and Hirose, which can find a local maximum likelihood (ML) estimate surely if it exists. Nevertheless, by Vera and Díaz-García it was shown that performance in finding a local ML estimate deteriorated by adopting the parameterization only and using other algorithm. In the present article, it will be shown that Komori and Hirose’s algorithm should be used for the parameterization. This work will also give MATLAB codes as a useful tool for the parameter estimation of the distribution.  相似文献   
2.
Summary Crowding effects of larvae on survival and development were examined for the broad-horned flour beetle,Gnathocerus cornutus (F.). The larvae matured about 3 weeks after hatching regardless of their densities, but pupation was severely hindered by crowding. There existed an upper limit for the number of the pupae produced and its mechanism was studied by a statistical analysis of the distribution patterns of pupal cells and the experiment in which glass tubes were artificially supplied in addition as pupation site. These studies show thatG. cornutus larvae have a habit to construct cells for pupation and this habit leads to a contest competition for pupation site at high densities. The significance of the contest competition for population regulation was discussed comparing the results onTribolium confusum Jacqueline duVal.  相似文献   
3.
We report our initial experience with salvage therapy for low responders to PDE-5 inhibitors by adding vitamin E. Of 89 patients with ED who visited our clinic between January 2004 to August 2006, 9 were unable to obtain a full response to a PDE-5 inhibitor and included in the present study. After providing informed consent, each was given 300 mg per day of α-tocophenol at least 1 month and completed IIEF-5 questionnaires to assess its efficacy while also taking a PDE-5 inhibitor. With α-tocophenol administration, the average IIEF-5 score increased from 13.8 ± 3.2 to 17.1 ± 3.6. Four of seven patients who completed the questionnaire each time showed improved IIEF-5 scores, with a maximum elevation of 9 points. Further, eight of the nine patients experienced favourable subjective changes, the majority being increased penile rigidity. The present clinical trial results are, to our knowledge, the first known to show the effects of vitamin E for enhancing the efficacy of a PDE-5 inhibitor.  相似文献   
4.
文章在分析日本宪法的和平主义内容、产生的背景、日本否定和平主义的潮流以及和平主义现状的基础上,阐述了日本政府修改宪法和平主义可能造成的后果以及日本国民守卫宪法和平主义的意义。  相似文献   
5.
Properties of the Weibull cumulative exposure model   总被引:1,自引:0,他引:1  
This article is aimed at the investigation of some properties of the Weibull cumulative exposure model on multiple-step step-stress accelerated life test data. Although the model includes a probabilistic idea of Miner's rule in order to express the effect of cumulative damage in fatigue, our result shows that the application of only this is not sufficient to express degradation of specimens and the shape parameter must be larger than 1. For a random variable obeying the model, its average and standard deviation are investigated on a various sets of parameter values. In addition, a way of checking the validity of the model is illustrated through an example of the maximum likelihood estimation on an actual data set, which is about time to breakdown of cross-linked polyethylene-insulated cables.  相似文献   
6.
汉族理想的死亡是在"后世"(阴间)幸福生活的条件.理想的死,需要具备生前长寿、临终前的必要准备、寿终的正常死亡及成为被子孙祭祀的祖先等必要条件.  相似文献   
7.
Abstract: Since the late 1980s the Brazilian population in Japan has steadily increased, despite the long‐term recession in the late 1990s. In this paper we will examine the mechanism of the constant increase of Brazilians in Japan, focusing on the institutional context of their incorporation into the Japanese labor market. On the demand side, Brazilians solved an acute labor shortage in the economic boom period, but long‐term recession and casualization of the labor market made them compete with other peripheral workers such as Japanese women and the aged. Thus Brazilians have been marginalized within the secondary labor market since the late 1990s. On the supply side, recruiting agencies and labor contractors established a “just‐in‐time” labor delivery system, which enabled “flexible staffing” in a highly fluctuating labor market. As a result, demand and supply for Brazilian workers is still on the increase. Working in Japan is getting less attractive for Japanese Brazilians but is more of a viable option for them, driving further migration from Brazil to Japan.  相似文献   
8.
数据挖掘技术中的聚类算法是解决客户细分问题的重要算法之一。为解决传统聚类算法在客户细分问题中分类精度较低、收敛速度较慢的问题,着重对比分析传统聚类算法中K-m eans、自组织映射网络和粒子群3种算法的不足,提出融合3种算法优点的混合型聚类算法,该算法利用K-m eans和自组织映射网络对初始聚类中心进行优化,结合粒子群优化和K-m eans优化聚类迭代过程,并在迭代优化过程中设计避免算法因早熟而停滞的机制。针对移动电子商务环境下的餐饮业客户细分问题,建立移动餐饮业客户细分模型,并利用混合型聚类算法、K-m eans、层级自组织映射网络和基于粒子群的K-m eans等4种算法对实际案例进行对比分析。研究结果表明,混合型聚类算法的聚类精度分别比其他3种算法高,同时还具有最快的收敛性能,更适用于客户细分问题。  相似文献   
9.
The authors examined the relationship between strength-training behavior and perceived environment in older Japanese adults. An Internet-based survey was conducted of 293 adults age 68.2 ± 2.8 yr. The dependent variable was regular strength-training behavior. The IPAQ environment module, access to facilities for strength training, and home equipment for strength training were environmental factors. Logistic-regression analysis was employed. After demographic variables (gender, age, educational background, household income, body-mass index, self-rated health status, smoking habit, and residential area) were adjusted for, home equipment for strength training (OR = 2.14, 95% CI = 1.50-3.06), access to facilities for strength training (OR = 2.53, 95% CI = 1.32-4.85), and observing active people (OR = 2.20, 95% CI = 1.06-4.58) were positively correlated with regular strength-training behavior. In conclusion, environmental factors associated with strength-training behavior were access to facilities for strength training, having home equipment for strength training, and observing active people.  相似文献   
10.
This paper uses labour force survey data to examine the employment rates and employment decisions of women with young children in the United States, Britain and Japan. Our results confirm that young children have a very strong negative effect on women's employment; this effect is most pronounced in Britain. We then take advantage of panel data to investigate the effects of family leave coverage on women's job retention after childbirth. We find that family leave coverage increases the likelihood that a woman will return to her employer after childbirth in all three countries, with a particularly marked effect in Japan. This result suggests that the recent expansions in family leave coverage in the sample countries are likely to lead to increased employment of women after childbirth. Received: 10 July 1997/Accepted: 8 June 1998  相似文献   
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