Mechanical and Aerospace Engineering Copyright (c) 2013 Syracuse University All rights reserved. http://surface.syr.edu/mae Recent documents in Mechanical and Aerospace Engineering en-us Mon, 28 Jan 2013 00:51:16 PST 3600 Model-Based Approach to Account for rhe Variation of Primary VOC Emissions Over Time in the Identification of Indoor VOC Sources http://surface.syr.edu/mae/13 http://surface.syr.edu/mae/13 Thu, 04 Oct 2012 08:25:15 PDT The study objectives were to improve the understanding of the long-term variation of VOC emission chromatograms of building materials and to develop a method to account for this variation in the identification of individual sources of VOC emissions. This is of importance for the application of the source identification method since materials age over time in real indoor environments. The method is based on the mixed air sample measurements containing pollutants from multiple aged materials and the emission signatures of individual new materials determined by PTR-MS. Three emission decay source models were employed and evaluated for their ability to track the change of individual material emission signatures by PTR-MS over a nine-month period. Nine building material specimens were studied in a ventilated 50-L small-size chamber for their emissions individually for nine months, and also in combination later. Chamber exhaust air was sampled by PTR-MS to construct a temporal profile of emission signature unique to individual product type. The similar process was taken to measure mixture emissions from multiple materials, which is for applying and validating the developed method for source identification enhancement, considering the variation in long-term emission rates of individual VOCs. Results showed that the proposed approach could predict the emission signatures of individual building materials at a later time (9-month) with less than 6% difference variance, and hence indicated the potential of the source identification method for aged materials in real indoor environments.

]]> Kwanghoon Han et al. Negative Pressure Characteristics of an Evaporating Meniscus at Nanoscale http://surface.syr.edu/mae/12 http://surface.syr.edu/mae/12 Fri, 03 Feb 2012 12:09:05 PST This study aims at understanding the characteristics of negative liquid pressures at the nanoscale using molecular dynamics simulation. A nano-meniscus is formed by placing liquid argon on a platinum wall between two nanochannels filled with the same liquid. Evaporation is simulated in the meniscus by increasing the temperature of the platinum wall for two different cases. Non-evaporating films are obtained at the center of the meniscus. The liquid film in the non-evaporating and adjacent regions is found to be under high absolute negative pressures. Cavitation cannot occur in these regions as the capillary height is smaller than the critical cavitation radius. Factors which determine the critical film thickness for rupture are discussed. Thus, high negative liquid pressures can be stable at the nanoscale, and utilized to create passive pumping devices as well as significantly enhance heat transfer rates.

]]> Shalabh Maroo et al. Combined Heat, Air Moisture and Pollutant Simulations (CHAMPS) For Buildings http://surface.syr.edu/mae/11 http://surface.syr.edu/mae/11 Tue, 24 Jan 2012 10:17:22 PST Jianshun Zhang et al. Understanding SVOCs http://surface.syr.edu/mae/10 http://surface.syr.edu/mae/10 Mon, 23 Jan 2012 11:33:49 PST Semi-volatile organic compounds (SVOCs) are an important class of indoor pollutants that are of great health concern. However, they have not received much attention within the ASHRAE community. This column provides an overview of the sources, sinks, transport mechanisms, and potential health effects, and discusses how HVAC systems may affect occupants’ exposure to SVOCs.

]]> Ying Xu et al. A framework for managing engineering change propagation http://surface.syr.edu/mae/9 http://surface.syr.edu/mae/9 Sun, 30 Jan 2011 16:57:55 PST Engineering Changes (ECs) are facts of life for any company developing and introducing new products, despite a commonly held notion that they are distractions from normal operation. Companies can become more innovative by utilising ideas from the ECs or by learning how to handle the ECs. This paper presents a framework to manage the ECs effectively, particularly the issue of EC propagation. An EC seldom confines itself to a single change, but triggers other changes in different components. The framework is designed to identify the affected components automatically, capture the required knowledge during the design phase of the product life cycle, and use it during the Engineering Change Management (ECM) process.

]]> Krishna Reddi et al. Enhancing systems integration by incorporating business continuity drivers http://surface.syr.edu/mae/8 http://surface.syr.edu/mae/8 Thu, 27 Jan 2011 08:43:49 PST Purpose – The purpose of this paper is to present a framework for developing an integrated operating environment (IOE) within an enterprise information system by incorporating business continuity drivers. These drivers enable a business to continue with its operations even if some sort of failure or disaster occurs.

Design/methodology/approach – Development and implementation of the framework are based on holistic and top-down approach. An IOE on server’s side of contemporary business computing is investigated in depth.

Findings – Key disconnection points are identified, where systems integration technologies can be used to integrate platforms, protocols, data and application formats, etc. Downtime points are also identified and explained. A thorough list of main business continuity drivers (continuous computing (CC) technologies) for enhancing business continuity is identified and presented. The framework can be utilized in developing an integrated server operating environment for enhancing business continuity.

Originality/value – This paper presents a comprehensive framework including exhaustive handling of enabling drivers as well as disconnection points toward CC and business continuity.

]]> Bajgoric Nijaz et al. A framework for managing engineering change propagation http://surface.syr.edu/mae/7 http://surface.syr.edu/mae/7 Thu, 27 Jan 2011 08:43:47 PST Engineering Changes (ECs) are facts of life for any company developing and introducing new products, despite a commonly held notion that they are distractions from normal operation. Companies can become more innovative by utilising ideas from the ECs or by learning how to handle the ECs. This paper presents a framework to manage the ECs effectively, particularly the issue of EC propagation. An EC seldom confines itself to a single change, but triggers other changes in different components. The framework is designed to identify the affected components automatically, capture the required knowledge during the design phase of the product life cycle, and use it during the Engineering Change Management (ECM) process.

]]> Krishna Reddi et al. Enterprise resource planning survey of Korean manufacturing firms http://surface.syr.edu/mae/6 http://surface.syr.edu/mae/6 Thu, 27 Jan 2011 08:42:10 PST Enterprise Resource Planning (ERP) systems are packaged software designed to integrate and optimise the business processes of an enterprise. The ERP systems have been embraced by industry as a de facto solution to integrate their business functions. The adoption of the ERP concept is a truly global phenomenon. This paper reports a recently completed survey study on Korean manufacturing firms. The study used the same survey questionnaires used in two previous surveys done on US and Swedish manufacturing firms. Our objective is to determine the extent of adoption of the ERP system in the Korean manufacturing firms, their motivations, implementation strategies and benefits obtained, and to provide useful data to draw similarities and differences between different countries’ practices.

]]> Lee TaeHyung et al. Enhancing ERP system’s functionality with discrete event simulation http://surface.syr.edu/mae/5 http://surface.syr.edu/mae/5 Thu, 27 Jan 2011 08:42:09 PST Purpose – To develop a methodology to augment enterprise resource planning (ERP) systems with the discrete event simulation’s inherent ability to handle the uncertainties.

Design/methodology/approach – The ERP system still contains and uses the material requirements planning (MRP) logic as its central planning function. As a result, the ERP system inherits a number of shortcomings associated with the MRP system, including unrealistic lead-time determination. The developed methodology employs bi-directional feedback between the non-stochastic ERP system and the discrete event simulation model until a set of converged lead times is determined.

Findings – An example of determining realistic production lead-time data in the ERP system is presented to illustrate how such a marriage can be achieved.

Research limitations/implications – The research demonstrates that the limited planning functionality of the ERP system can be complemented by external system such as discrete event simulation models. The specific steps developed for this research can be adopted for other enhancements in different but comparable situations.

Practical implications – The organizations who have been using the discrete event simulation in their planning and decision-making processes can integrate their simulation models and the ERP system following the steps presented in this paper. The ideas in this paper can be used to look for automatic data collection process to update or build the simulation models.

Originality/value – The ERP implementation is a significant investment for any corporation. Once the ERP implementation is completed successfully, the corporations must look for ways to maximally return on their investment. The research results may be used to enhance the implemented ERP systems or to fully utilize the capabilities in a corporation.

]]> Young Moon et al. Enterprise Resource Planning (ERP): a review of the literature http://surface.syr.edu/mae/4 http://surface.syr.edu/mae/4 Thu, 27 Jan 2011 08:34:33 PST This article is a review of work published in various journals on the topics of Enterprise Resource Planning (ERP) between January 2000 and May 2006. A total of 313 articles from 79 journals are reviewed. The article intends to serve three goals. First, it will be useful to researchers who are interested in understanding what kinds of questions have been addressed in the area of ERP. Second, the article will be a useful resource for searching for research topics. Third, it will serve as a comprehensive bibliography of the articles published during the period. The literature is analysed under six major themes and nine sub-themes.

]]> Young Moon The Open Assembly Model for the Exchange of Assembly and Tolerance Information: Overview and Example http://surface.syr.edu/mae/3 http://surface.syr.edu/mae/3 Tue, 05 Oct 2010 09:02:52 PDT In early design phases an effective information exchange among CAD (Computer Aided Design) tools depends on a standardized representation for the product data in all PLM (Product Lifecycle Management) tools. The NIST Core Product Model (CPM) and its extension are proposed to provide the required base-level product model that is open, non-proprietary, generic, extensible, independent of any one product development process and capable of capturing the full engineering context commonly shared in product development [1]. The Open Assembly Model (OAM) Model extends CPM to provide a standard representation and exchange protocol for assembly. The assembly information model emphasizes the nature and information requirements for part features and assembly relationships. The model includes both assembly as a concept and assembly as a data structure. For the latter it uses the model data structures of ISO 10303, informally known as the Standard for the Exchange of Product model data (STEP)[2]. The objective of the paper is to show how the OAM can be used to realize seamless integration of product information, with an emphasis on assembly, throughout all phases of a product design. A gearbox design example is used to illustrate the process.

]]> M. M. Baysal et al. Guidelines for the development of computer-based instruction modules for science and engineering http://surface.syr.edu/mae/2 http://surface.syr.edu/mae/2 Tue, 05 Oct 2010 08:48:30 PDT The design and development of a prototype computer-based instruction (CBI) module is described. The module covers introductory structural analysis techniques and demonstrates the practicality of CBI for undergraduate engineering education. The module’s generic learning objectives are used to develop a set of guiding principles for CBI development. Choice of authoring software and the module architecture are presented, followed by the details of the user interface, logic, and screen layout. The module design and software development process outlined here are easily extended to computer-based tutorials that present problem solving methods for engineering, mathematics, and the natural sciences.

]]> Jessica R. Lux et al. The Open Assembly Model for the Exchange of Assembly and Tolerance Information: Overview and Example http://surface.syr.edu/mae/1 http://surface.syr.edu/mae/1 Tue, 05 Oct 2010 08:48:29 PDT In early design phases an effective information exchange among CAD (Computer Aided Design) tools depends on a standardized representation for the product data in all PLM (Product Lifecycle Management) tools. The NIST Core Product Model (CPM) and its extension are proposed to provide the required base-level product model that is open, non-proprietary, generic, extensible, independent of any one product development process and capable of capturing the full engineering context commonly shared in product development [1]. The Open Assembly Model (OAM) Model extends CPM to provide a standard representation and exchange protocol for assembly. The assembly information model emphasizes the nature and information requirements for part features and assembly relationships. The model includes both assembly as a concept and assembly as a data structure. For the latter it uses the model data structures of ISO 10303, informally known as the Standard for the Exchange of Product model data (STEP)[2]. The objective of the paper is to show how the OAM can be used to realize seamless integration of product information, with an emphasis on assembly, throughout all phases of a product design. A gearbox design example is used to illustrate the process.

]]> M. M. Baysal et al.