Hung T.-C.,Chinese Military Academy |
Chang S.-H.,National Sun Yat - sen University |
Hsu S.-P.,CTCI Corporation |
Su Y.-T.,National Sun Yat - sen University
Journal of Materials Processing Technology | Year: 2011
In this paper, a 'rock-and-roll' polishing strategy is proposed for reducing the influence of tool wear on machining rates during hydrodynamic polishing. An analytical study suggests that the radius of curvature of spherical tools changes rapidly during the tool wear process. In addition, variations in the tool radius have a significant effect on machining rates. Increasing the contact length of the tool rapidly decreases the variation in the tool's radius of curvature. A rock-and-roll polishing strategy is therefore proposed to increase the contact length of the tool. This strategy is proposed to design the tool's rocking motion with an appropriate dwelling-time distribution so as to increase the area (or contact length) of the wear zone and create a uniform wear depth, which will in turn reduce the variation in the tool radius. A separate volume removing analysis of the tool wear suggests that the dwelling time of a tool at a given position can be determined for a given wear depth and wear rate. Finally, an experimental study confirms that the proposed strategy can reduce the variation in the tool's radius of curvature and that the effect of tool wear on the machining rate can be suppressed. © 2011 Elsevier B.V. All rights reserved.
Khetarpal P.,Petronet LNG Ltd |
Chen J.-W.,National Cheng Kung University |
Chen F.-C.,CTCI Corporation |
Mathews P.,LOTS Shipping Ltd
Proceedings of the International Offshore and Polar Engineering Conference | Year: 2012
This study introduces the construction practice for the LNG (Liquefied Natural Gas) unloading arm installation at Kochi Vypeen Island in south India. The difficulties faced and solutions implemented provide a very practical reference to any similar maritime projects. The first attempt to install unloading arms was suspended for 5.5 months due to unsteady sea condition when southwest monsoon swept the project site. Through a multi-companies teamwork building and brainstorming, an effective solution using a spudded tidal barge was proposed and implemented resulting in the installation being successfully completed. Copyright © 2012 by the International Society of Offshore and Polar Engineers (ISOPE).
Wu Y.-K.,National Penghu University of Science and Technology |
Lee C.-Y.,Tungnan University |
Liu L.-C.,CTCI Corporation |
Tsai S.-H.,Hwa Hsia University of Technology
IEEE Transactions on Power Delivery | Year: 2010
This paper proposes a reconfiguration methodology based on an Ant Colony Algorithm (ACA) that aims at achieving the minimum power loss and increment load balance factor of radial distribution networks with distributed generators. A 33-bus distribution system and a Tai-Power 11.4-kV distribution system were selected for optimizing the configuration and to demonstrate the effectiveness of the proposed methodology for solving the optimal switching operation of distribution systems. The simulation results have shown that lower system loss and better load balancing will be attained at a distribution system with distributed generation (DG) compared to a system without DG. Furthermore, the simulation results also satisfy and suitability reference merits of the proposal method. © 2010 IEEE.
Chiu Y.,Chung Yuan Christian University |
Su D.,CTCI Corporation
Journal of the Chinese Institute of Industrial Engineers | Year: 2010
Decision-makers frequently need to develop new strategic plans to correct weaknesses or build new strengths for a changing business condition. Although numerous studies have addressed the economic product quantity problem, most are unable to cope with the defective products identified during processing. While some investigations have considered the cost of defective products, these studies have only considered the two outcomes of acceptance or rejection, and thus fail to accurately reflect the complexity of product quality. Therefore, this study adopts the Taguchi loss function, a kind of quality cost to measure product quality. In addition, many economic product quantity and economic order quantity models cannot accurately predict cost because they ignore the time-value of money, and thus this study employs the time-value of money. Furthermore, this study also considers the exponential process quality improvement function as a method of estimating how investment reduces process variation. As a result, this study considers the quality cost, the time-value of money, and the exponential process quality improvement function in constructing a new total cost model to optimize the production period, and initial investment in process improvement so as to minimize total cost. © 2010 Chinese Institute of Industrial Engineers.
Tserng H.P.,National Taiwan University |
Lin W.-S.,National Taiwan University |
Li C.-C.,National Central University |
Li C.-C.,CECI Engineering Consultants Inc. |
And 2 more authors.
Journal of Marine Science and Technology (Taiwan) | Year: 2015
Performance analyses of consultancy firms usually include man-hour analyses, schedule analyses and budget analyses. During the project management process, the project scope change makes it difficult for the management to control the project and predict the future trends. This research has developed a project performance measurement model based on the concepts of CAPP (Continuous Assessment of Project Performance) and PMBOK (Project Management Body of Knowledge), created by the Construction Industry Institute and PMI (Project Management Institute). Through data collection, analysis, and summary, this study establishes a historical database, reviews existing records, and selects major and significant performance evaluation indicators from the project data, as well as building of relevant models. Through an established Web-based project performance measurement system to identify the project implementation performance trend, it allows participants in various stages of the construction engineering life cycle to exchange and share engineering performance information and experience. © 2015, National Taiwan Ocean University. All rights reserved.
Chang J.-S.,Tatung University |
Zhang Y.-C.,Tatung University |
Chen C.-C.,Tatung University |
Ling T.-R.,I - Shou University |
And 4 more authors.
Industrial and Engineering Chemistry Research | Year: 2014
One-step synthesis of an octane booster for gasoline and a diesel fuel was performed using glycerol and tert-butyl alcohol (TBA) as raw materials and the solid acid Amberlyst-70 (A-70) as a catalyst. In contrast to the conventional etherification of glycerol with TBA operated at a low temperature resulting in a homogeneous product mixture, our study revealed that the same process at elevated reaction temperatures would automatically separate the products into an organic phase and an aqueous phase. The components of the former consisted of unconverted TBA, isobutylene (IB), 2,2,4-trimethyl-1-pentene, 2,4,4-trimethyl-2-pentene (DIB), 2,2,4,6-pentamethyl-3-heptene, 2,2,6,6-tetramethyl-4-methyleneheptane (TIB), and oxygen-limited hydrocarbons (HCs), which are constituents that are different from the product distribution of the conventional reaction. The latter was composed of water, unconverted TBA, and glycerol. After a simple laboratory distillation of the organic phase product mixture, the distillate obtained by a simple distillation maintained at 225 °C in the still could be used as an octane booster for gasoline, while the residue could be adopted as diesel fuel. © 2014 American Chemical Society.
Chang A.S.-T.,National Cheng Kung University |
Shih J.S.,National Cheng Kung University |
Choo Y.S.,CTCI Corporation
Journal of Engineering Design | Year: 2011
Design change increases cost and time of production and redesign substantially. This research proposes a framework to investigate the reasons and their respective production change and redesign costs for design changes during production. It analyses 339 change items and interviews designers, owners and contractors of seven construction projects. Research findings show that design changes result from three categories of reasons: under owner's, designer's, and beyond control. The proportions of change reasons, construction change costs and redesign costs are different for the studied projects. The redesign costs are from 2.1% to 21.5% and on average 8.5% of the construction change cost, equivalent to the fee of a new design project. The identified reasons with quantitative cost behaviours can help clarify design change problems. Insight about design change can also be gained through the convergence of different perceptions of change reason proportions from project participants. The analysis process and results in this research can be referenced by other companies to obtain their own patterns of reasons, production change, and redesign costs from design changes to diagnose design performance. © 2011 Taylor & Francis.