Industrial Engineering Letters
http://www.iiste.org/Journals/index.php/IEL
<p><span id="internal-source-marker_0.04939836589619517">Industrial Engineering Letters <span id="internal-source-marker_0.04939836589619517">is a peer reviewed journal published by IISTE. The journal publishes original papers at the forefront of industrial engineering research, covering theoratical modeling, inventory, logistics, optimizations methods and their applications. The journal is published in both printed and online versions. The online version is free access and download.</span></span></p><p><span><span>IISTE is member of <a href="http://www.crossref.org/01company/17crossref_members.html">CrossRef</a>.<br /></span></span></p>en-USadmin@iiste.org (Alexander Decker)admin@iiste.org (John Nagoo)Sun, 30 Nov 2014 14:46:15 +0000OJS 2.3.7.0http://blogs.law.harvard.edu/tech/rss60Some Results on Complete Metric Space
http://www.iiste.org/Journals/index.php/IEL/article/view/17199
<p>In the present paper we established some fixed point and common fixed point theorems in complete metric spaces for new rational expressions.Our results are genralizatyion of many known results</p> <p><strong>Kew words:</strong> Complete Metric Space, Fixed Point, and Common Fixed Point.</p>P.L. Sanodia, Aakanksha Pandeyhttp://www.iiste.org/Journals/index.php/IEL/article/view/17199Effects of Radiation and Magnetic field on the flow and heat transfer of a nanofluid in a rotating frame
http://www.iiste.org/Journals/index.php/IEL/article/view/17200
<p>We analysed the flow and heat transfer characteristics of a nanofluid in porous medium bounded by a moving vertical semi-infinite permeable flat plate in presence of constant heat generation/absorption, radiation and chemical reaction in a rotating frame. The slip velocity is assumed to oscillate in time with constant frequency so that the solutions of the boundary layer are the same as oscillatory type. The dimensionless governing equations for this investigation are solved analytically using perturbation approximation. In this study two types of nanofluids, namely -water and -ethylene glycol are used and the heat transfer characteristics are analysed for different shapes of nano particles. The effect of various parameters on the flow and heat and mass transfer characteristics are discussed through graphs.</p> <p><strong>Key Words</strong>: Radiation, Rotation, Chemical Reaction, Convection, MHD.</p>V. Sugunammahttp://www.iiste.org/Journals/index.php/IEL/article/view/17200Determination of Optimal Crew Size in Project Segmentation to Minimize Cost
http://www.iiste.org/Journals/index.php/IEL/article/view/17201
<p>Stakeholders and contracting board have begun to utilize innovative contracting methods that provide new incentives for reducing construction duration. These methods have placed increasing pressure on decision makers in the construction industry to search for an optimal construction plan that minimizes construction time and cost while preserving quality. This paper considers the problem of finding the optimal number of segment(s) that minimizes total project cost of a non-homogenous road construction project located in a city in South West, Nigeria. A mathematical programming model approach was adopted to obtain the optimal number of segments as opposed to when the activities of the project are scheduled sequentially. Also, Binary interaction matrix (BIM) was used to define stated relationships between fixed and variable quantities of the cost and duration respectively. Given stipulated due date of 8 months with a penalty / bonus of <span style="text-decoration: line-through;">N</span> 63091791/month. The analysis shows that the optimal number of segments into which the project can be divided into is three and that by working in parallel the project will be completed in 5 months at a cost of <span style="text-decoration: line-through;">N</span>1,409,609,413. This is opposed to the original contract lump sum of <span style="text-decoration: line-through;">N</span> 1, 577, 294, 775 with a normal duration of 12 months. A saving of 1.55% was realized. This work demonstrated the possibility of dividing a continuous repetitive project into a numbers of segments of equal work content, working in parallel, using optimum crew size such that the duration and the total cost of the project can be minimized.</p> <p><strong>Key words</strong>: Project Management, Scheduling, Construction planning, Natural Rhythm, Project Segmentation</p>Babatunde Omoniyi Odedairo, Oluwabukunmi .A. Ogunsanya, Berkly Ogagaoghene Anarohttp://www.iiste.org/Journals/index.php/IEL/article/view/17201A coupled evaluation and optimization approach to drive product variety towards sustainability
http://www.iiste.org/Journals/index.php/IEL/article/view/17202
<p>Increasing customer demands for highly personalized and environmentally friendly products urge companies to find new ways for managing their production systems. The aim is to cope with diversity of items while delivering profitable products with lower environmental impact. This paper proposes a coupled evaluation and optimization approach to steer product variety towards environmental and economic sustainability. A predefined set of indicators enriched with weights given by the user ensures the evaluation, while optimization uses linear programming. The paper highlights the impact of variety steering on environmental and economic sustainability indicators. Additionally, the paper underlines the need to translate regulations into concrete company goals through integrating carbon markets into the proposed model.</p> <p><strong>Keywords: </strong>sustainability, evaluation, variety, linear programming, analytic hierarchy process</p>Khaled Medinihttp://www.iiste.org/Journals/index.php/IEL/article/view/17202