• Journal of the Korean Society of Manufacturing Process Engineers
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• v.14 no.4
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• pp.108-117
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• 2015

In this paper, as a previous step of software development, through an analysis step in the basic design process of the FPSO crane, ERD, which could help develop common understanding between its developer and the user, was introduced. From the flowchart of the design process, the overall work flow in its development was understood. Then, after the design process of the crane was divided into many entities, the attributes of each entity were defined and the relationships between the entities were established, followed by ERD creation through the use of IDEF1X notation. The results of the analysis can be readily understood even by users who lack of software knowledge, and then their change requirements can be immediately reflected in the developed system that requires modification.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.1
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• pp.91-96
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• 2002

Recently industry has moved towards automated operations with the goal of achieving better product quality greater productivity and reliability The pump design in characterized by extensive utilization of the related database which contains performance data. The inputs to the system are through interactive dialogue sessions and the basic input consist of flow rate, head, of fluid efficiency and the customer special requirements. These basic inputs along with the numerous rules in the knowledge bases and the mathematical modeling enable the effective design of the pump industry This paper represents the development of an automatic pump design system that was composed of a main program the data input module the drawing module the drawing edit module and was programed by the AutoLISP language under the Auto CAD program The developed system ultimately generates the design for a pump through the AutoCAD language.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.1
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• pp.7-14
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• 1986

To predict the fuel clad temperature during the reflooding phase of a LOCA, one may need a knowledge of reflood heat tranfer mechanism in a rod bundle. For this purpose reflooding experiments have been carried out with an electrically heated 3*3 rod bundle. Using the method for the determination of local heat transfer coefficient from the measured wall temperature the parametric effects of coolant flow rate, initial wall temperature, coolant subcooling and heat generation rate on the propagation of rewetting front were investigated. Prediction of the wall temperature histories for these experiments was discussed using REFLUX code with modification of the rewetting temperature correlation. Through this modification, better agreement between experiment and prediction was obtained.

• Plant Journal
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• v.7 no.3
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• pp.65-73
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• 2011

This research has suggested a method to select pipe wall thickness by application of the value engineering to reduce the cost and quantity that are major part of construction materials. This research shows that the application of value engineering reduces the cost of piping materials by optimizing pipe wall thickness while maintaining process flow date of design pressure and design temperature. Based on this knowledge, the application of the value engineering will lead to the cost reduction and quantity reduction by effective selection of pipe wall thickness. The application of the value engineering will help the EPC companies to win a contract in the overseas plant market.

• Journal of The Korean Association For Science Education
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• v.25 no.6
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• pp.642-649
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• 2005

Argumentative discussion is one of the important components of an educational program, which allows students not only to learn the process of social negotiation through discussions, but also to improve students' overall research abilities. The purpose of this study was to examine a) the changes between inquiry of before-argumentative discussion and inquiry of after-argumentative discussion, and b) the connections between the inquiry changes and online argumentative discussion. This study analysed 726 messages in an online argumentative discussion, as well as in first research reports and second research reports. The results of the study indicate that science-gifted students' research abilities were improved through on-line argumentative discussion that provided them with feedback based on interactive discussions, and encouraged them to re-examine hypotheses and experiment processes. The science-gifted students showed knowledge and abilities for identifying simple errors in research processes and arguing problems in the flow of the whole logic of research.

• Journal of Mechanical Science and Technology
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• v.18 no.10
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• pp.1799-1808
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• 2004

Knowledge of airflow characteristics in nasal cavity is essential to understand the physiological and pathological aspects of nasal breathing. Several studies have utilized physical models of the healthy nasal cavity to investigate the relationship between nasal anatomy and airflow. Since the final goal of these works is their contribution to the diagnosisand treatment of nasal diseases, the next step on this topic is naturally studies for disordered nasal cavities. In this paper, as the first application, airflows in the normal and abnormal nasal cavities with adenoid vegetation are investigated experimentally by PIV, and comparisons of both cases are appreciated. Dense CT data and careful treatment of model surface under the ENT doctor's advice provide more sophisticatedcavity model. The CBC PIV algorithm with window offset is used for PIV flow analysis. Average and RMS distributions are obtained for inspirational and expirational nasal airflows. Airflow characteristics that are related with the abnormalities in nasal cavity are presented.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.408-409
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• 2008

This paper presents a new development for topology optimization of heat-dissipating structure with forced convection. To cool down electric devices or machines, two types of convection models have been widely used: Natural convection model with a large Archimedes number and Forced convection with a small Archimedes number. Nowadays, many engineering application areas such as electrochemical conversion device or fuel cell devices adopt the forced convection to transfer generated heat. Therefore, to our knowledge, it becomes an important issue to design flow channels inside which generated heat transfer. Thus, this paper studies optimal topological designs considering fluid-heat interaction. To consider the effect of the advection in the heat transfer problem, the incompressible Navier-stokes equation is solved. This paper numerically studies the coupling phenomena and presents optimal channel design considering forced convection.

• Journal of Korea Foundry Society
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• v.10 no.5
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• pp.408-416
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• 1990

The application of this new design approach called fracture mechanics allow one to determine the maximum allowable stress from the knowledge of the largest expected flow size and the plane strain fracture toughness of a material. In this study we examined the relation between retained austenite, mechanical property and fracture toughness accompanied by austempering heat treatment. Fracture toughness values and retained austenite volume were higher with the ADI(austempered ductile iron) which were austempered at $380^{\circ}C$ than austempered at $320^{\circ}C$. Additionally, fracture toughness values were increased for 1~2 hour austempering time but it was slowly decreased for 5 hour ADI maintaining the predominant fracture toughness($K_{IC}:83MPa{\sqrt{m}}$) is obtained following condition, namely, austempering temperature and time ($380^{\circ}C$ and 1 hour).

• Proceedings of the KSME Conference
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• 2000.11a
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• pp.783-788
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• 2000

Hydroforming is a method for forming circular tubes. If this technology is to be applied economically, it is essential to have knowledge of the avoidance of failure cases as well as of the behavior of the tube in the tool under the compressive stress and forces that are exerted by the machine. A finite element simulation for manufacturing of lower arm from straight tubes, using the hydroforming method, was performed to investigate the effects of varying process parameters. Explicit method is used to simulate hydroforming in many cases, but that is not included flow rule. And then it needs simulation for implicit method. It was simulated by two methods, implicit and explicit, to compare the result of the hydroforming.

• Asia-Pacific Journal of Business
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• v.4 no.2
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• pp.11-20
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• 2013

This study extends the extant scope of understanding investment decision, beyond the dominant 'technical' emphasis on the application of discounted cash flow techniques. The research methodology draws the positivist and interpretive research paradigms. It uses a deductive approach, survey strategy and principal component analysis for the analysis. Three key sets of factors emerged as important in the investment decision process in the hydropower sector. They are: group consensus (framing), influences on own judgment (heuristics), and application of knowledge & experience (intuition). The use of purposive and convenient sampling might have some unintended impact on the findings. Consequently, any generalizations of the findings to a wider population of organizations and managers need to be made with care. It is hoped that this paper will encourage other researchers to go beyond the analytic techniques of investment appraisal that have dominated investment decision research and seek to balance the emphasis by focusing on human involvement and behavioral aspects of investment decision.