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Dimensional variations often cause expensive problems in the assembly of mechanical products especially during new product deployment. Currently, the time and labour spent on the removal of variation-related assembly problems are considerable. This paper proposes a computational method to identify the causes of variation-related problems in assemblies. In the proposed method, the relationship between causes and symptoms is computed via simulation of the assembly process, and they are represented by a matrix. For given measurement data, this method uses linear optimization and statistical techniques to diagnose assembly problems. The proposed method can diagnose assembly problems caused by either a single or multiple fault(s). [ABSTRACT FROM AUTHOR]

Highlights: [•] Methodology using ANN and genetic algorithm to perform multi-optimization. [•] Objective-functions are annual energy consumption and summer comfort degree. [•] Optimization variables are thermophysical properties of external envelope. [•] Optimized solutions are given as a function of the climate. [•] More accurate results with multi-objective optimization than with enhanced mono-objective optimization. [ABSTRACT FROM AUTHOR]

This article deals with laminar natural convection in three-dimensional air-filled enclosures. The cavities under investigation have two opposite isothermal vertical walls and four adiabatic walls. The vertical and horizontal aspect ratios are in the range 5–80 and 0.2–5, respectively. The Rayleigh numbers vary between 103 and 105. These values match cavities typically found in vertical hollow alveolar bricks. The effects of the geometry and the Rayleigh number on the convection are discussed. Comparisons between purely two-dimensional cases and the results obtained in 3D are presented and analyzed. Nusselt number correlations as a function of the two aspect ratios and Rayleigh number are proposed, offering an efficient tool for thermal engineers and scientists to evaluate convection heat transfer in real three-dimensional enclosures, which are common systems in building construction. [ABSTRACT FROM PUBLISHER]

Subungueal splinter hemorrhage (S.U.S.H.) has been reported in various conditions and may herald a serious systemic disease. It has been related to miscellaneous conditions such as: subacute bacterial endocarditis, severe rheumatoid arthritis, uninfected mitral stenosis, trichinosis, peptic ulcer, hypertension, neoplasm, trauma, and in some cases, is considered idiopathic. Some dermatologic conditions such as psoriasis, dermatitis, and fungal infections may also produce S.U.S.H. It consists of "a homogeneous mass of blood in a layer of squamous cells, adherent to the under surface of the nail, considered to be of embolic origin." In a brief review of pertinent medical literature on thromboangiitis obliterans, we were unable to find a description of its occurrence in this disease. The earliest lesions described in this condition are "painful vesicles on the pulp of digits with intense hyperhemia and hypersensitivity of the surrounding skin. It is our opinion that S.U.S.H. is an earlier and quite useful sign of arterial involvement as seen in the following cases observed in our vascular disease section. [ABSTRACT FROM AUTHOR]