This paper surveys the literature related to maintenance policies for single and multi -unit systems. The emphasis is on work appearing in different periods. The literature is divided into two main categories Single and multiunit system. The single unit system is divided into six sub-categories like: Age-dependent, Periodic, Failure limit policy, Sequential, Repair limit, Repair number counting...

mycotic aneurysm could be divided into three types according to their etiology: septic-embolic, cryptogenic and traumatic type. during the period from 1972 to 1974 two cases of mycotic aneurysms have been seen at the ohio valley medical center - one following a sub acute bacterial endocarditic and another one was two years following surgery for aortofemoral bypass graft. the clinical course of ...

It is proved that equations between arrows assumed for cartesian categories are maximal in the sense that extending them with any new equation in the language of free cartesian categories collapses a cartesian category into a preorder. An analogous result holds for categories with binary products, which may lack a terminal object. The proof is based on a coherence result for cartesian categorie...

This studyutilized the mobile signaling data to conductthe impact analysis of jobs-housing spatial mismatch on commuting behavior, with eight typical employment centers of three categories selected as the research subjects. Based on the analysis of the characteristics and indictors including commuting distance, accessibilities from cumulative opportunity model etc., this study demonstrates that...

abstract: this paper investigates the factors accelerating smes' adoption of e-commerce. initially we proposed a model that included three categories of factors including external environmental factors, internal environmental factors and technology specifications. in addition, we proposed ecommerce adoption stages in two levels of early adoption and institutionalization. based on surveying...

background: liver cirrhosis was one of the most important liver diseases. other chronic liver diseases could be lead to liver cirrhosis. liver cirrhosis could be lead one kind of liver cancers named hepatocellular carcinoma. cirrhosis in the early stages just by laboratory and imaging testes could be diagnosed. in this study cirrhotic patients were classified based on laboratory symptoms. for t...