Reliability Test Plan Based on Logistic-Exponential Distribution and Its Application

In this article, a reliability test plan is developed for Logistic-exponential distribution (LoED) under time truncated life test scheme. The distribution has been chosen because it can used to model lifetime of several reliability phenomenon and it performs better than many well known existing distributions. With the discussions of statistical properties of the aforesaid model, the reliability test plan has been established under the assumption of median quality characteristics when minimum confidence level P* is given. To quench the objective of the paper i.e; to serve as a guiding aid to the emerging practitioners, minimum sample sizes have been obtained by using binomial approximation and Poisson approximation for the proposed plan. Further, operating characteristic (OC) values for the various choices of quality level are placed. Also, minimum ratio of true median life to specified life has been presented for specified producer’s risk. Important findings of the proposed reliability test plan are given for considered value of k=0.75,1,2. To demonstrate the appropriateness of suggested reliability test plan is achieved using four real life situation.

Snowfall reduces the risk of chronic subdural hematoma onset: Analysis of an administrative database in Japan

Background: Chronic subdural hematoma (CSDH) is a frequently observed disease in neurosurgical practice. Although first snowfall has been considered to increase the onset of CSDH, few reports have assessed the relationship between snowfall and CSDH. In this study, we aimed to investigate the relationship between CSDH onset and first snowfall events. Methods: This retrospective study was based on the Japanese Diagnosis Procedure Combination inpatient database from July 1, 2010, to March 31, 2016, and on the global observation of snowfall events in Japan obtained from the Japan Meteorological Agency. We used a binomial approximation to evaluate the average number of CSDH patients after first snowfall events compared with that before first snowfall events. We calculated the odds ratio of CSDH onset on the first snowfall. Results: We identified 8526 CSDH patients from the database. A total of 5573 (65.4%) were observed before first snowfall events, and 2953 (34.6%) after first snowfall events. The first snowfall of winter was significantly associated with a reduction in the occurrence of CSDH (odds ratio, 0.53; 95% confidence interval; 0.51–0.55). In subgroup analysis, only the first snowfall in October was not associated with reduction in the occurrence of CSDH. Conclusion: First snowfall events did not affect the onset of CSDH in Japan.

Pratiques culturales et gestion post-récolte du sorgho au Sénégal

La non maîtrise ou l’ignorance des bonnes pratiques de stockage ou de conservation conduit souvent à des pertes des récoltes en Afrique. Ces dernières peuvent entrainer l’insécurité alimentaire qui est toujours une réalité en Afrique. Ceci illustre que les pratiques culturales et surtout la conservation post-récolte des céréales principaux aliments de base des populations, demeurent un problème majeur en Afrique. Une enquête a été réalisée au Sénégal dans les régions de Tambacounda et de Thiès pour étudier les pratiques culturales des producteurs de sorgho et caractériser la gestion post-récolte dans les zones de production. L’étude a été réalisée auprès de 384 producteurs de sorgho issus de 44 villages. Les zones ont été choisies suivant leur niveau de production et de pluviométrie. La taille de l’échantillon a été déterminée en utilisant l’approximation normale de la loi binomiale. Les résultats ont montré que dans chacune des régions, la proportion d’agriculteur masculin est de 97% et les ethnies dominantes sont les sérères (86%) à Thiès, les peuls et les wolofs (47% et 21%) à Tambacounda. Les semences provenaient principalement de la récolte précédente (10 à 76%) des cas et des distributeurs d’intrants agricoles (2 à 65%). Ces taux diffèrent suivant la région. Les variétés certifiées sont cultivées par 70% des producteurs à Thiès. Les variétés traditionnelles sont utilisées par 98% de ceux de Tambacounda. Cette étude a aussi révélé que les paysans utilisent différents types de séchage à la maison ou aux champs. Parmi eux 79% stockent leur récolte dans des cases, 14% dans des magasins communautaires ,7% dans des greniers sous forme de panicules ou de grains représentant respectivement 22 et 75%. Ces méthodes de prise en charge post-récolte du sorgho diffèrent selon la zone et sont dans certains cas inadéquates. Elles peuvent favoriser la déperdition post-récolte du sorgho et sa contamination par les moisissures, d’où l’intérêt de bien former les acteurs de cette filière.Mots clés : Culture, stockage, céréale, enquête, variété. English Title: Cultural practices and post-harvest management of sorghum in Senegal Failure to master or ignore good storage or conservation practices often leads to crop loss or spoilage of food in Africa. These can lead to food insecurity and threaten food safety. As a result, cultivation practices and especially the post-harvest conservation of cereals, the main staple food of the populations, remain a major problem in West Africa. A survey was carried out in Senegal in the regions of Tambacounda and Thies to study the cultural practices of sorghum producers and characterize post-harvest management in the production areas. The study was carried out with 384 sorghum producers from 44 villages. The zones were chosen according to their level of production and rainfall. The sample size was determined using the normal binomial approximation. The results showed that in each of the regions, the proportion of male farmers is 97%, and the dominant ethnic groups are the Serer (86%) in Thies, the Peul and the Wolof (47% and 21%) in Tambacounda. The seeds came mainly from the previous harvest (10 to 76%) of the cases, and from agricultural input distributors (2 to 65%). These rates differ by region. The certified varieties are cultivated by 70% of the producers in Thies. The traditional varieties are used by 98% of those of Tambacounda. This study also revealed that farmers use different types of drying at home or in the fields. Among them, 79% store their harvest in huts, 14% in community stores, 7% in granaries in the form of panicles or grains, representing 22 and 75% respectively. These post-harvest management methods for sorghum differ by area and are in some cases inadequate. They can encourage the post-harvest loss of sorghum and its contamination by molds, hence the importance of properly training the players in this sector.Keywords: Crop, storage, cereal, survey, variety.