• Corrosion Science and Technology
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• v.14 no.3
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• pp.120-126
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• 2015

The usage of bending products recently have increased since many industries such as automobile, aerospace, shipbuilding, and chemical plants need the application of pipings. Bending process is one of the inevitable steps to fabricate the facilities. Induction heat bending is composed of compressive bending process by local heating and cooling. This work focused on the effect of induction heat bending process on the properties of ASME SA312 Gr. TP304 stainless steel pipes. Tests were performed for base metal and bended area including extrados, intrados, crown up, and down parts. Microstructure was analyzed using an optical microscope and SEM. In order to determine intergranular corrosion resistance, Double Loop Electrochemical Potentiokinetic Reactivation (DL-EPR) test and ASTM A262 practice A and C tests were done. Every specimen revealed non-metallic inclusion free under the criteria of 1.5i of the standard and the induction heat bending process did not affect the non-metallic inclusion in the alloys. Also, all the bended specimens had finer grain size than ASTM grain size number 5 corresponding to the grain sizes of the base metal and thus the grain size of the pipe bended by induction heat bending process is acceptable. Hardness of transition start, bend, and transition end areas of ASME SA312 TP304 stainless steel was a little higher than that of base metal. Intergranular corrosion behavior was determined by ASTM A262 practice A and C and DL-EPR test, and respectively step structure, corrosion rate under 0.3 mm/y, and Degree of Sensitization (DOS) of 0.001~0.075% were obtained. That is, the induction heat bending process didn't affect the intergranular corrosion behavior of ASME SA312 TP304 stainless steel.

• Archives of design research
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• v.13
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• pp.27-42
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• 1996

With the rapid development of nowadays technologies, the environment of product development is experiencing structural changes than ever. Manufacturers are put under never-experienced pressures to launch their products in the market both faster and less expensively than their competitors while continuously improving product quality These pressures have given birth to so-called, Concurrent Engineering which is a systematic approach to the integrated, concurrent design of products and their related processes, including manufacture and support. Most manufactiring companies now recognize the importance of concurrent engineering and put heavy emphasis on the research and impementation of concurrent engineering. However, with this fundamental change in the process of product development, designers rarely pay attention to this newly demanding process. Designers still stay in the middle of process, satisfying their roles in dealing with aesthetic points of product. Designers badly need to incorporate the concept of concurrent engineering to design to design process and to adapt to this new environment. With these backgrounds, the study sets the objective to understand the nature of concurrent engineering and explore the possibility of it's application to industrial design. Particularly this study focuses on how the concept of concurrent engineering can be applied from the stage of form development to prototyping. At first, background, objectives, and scope of the study are discussed as an introductory part. It is followed by reviewing theories of concurrent engineering such as definition, history, technologies, examples, state of art and so on. Subsequently industrial design is viewed in terms of concurrent engineering and problems in industrial design are identified. Base on the findinss of precedent part of study, new process of industrial design incorporating concurrent engineering is developed. For the demonstration of new process, a case study of design of palm-top printer is introduced. Case study shows how the sketch, and forms can be transformed into prototyping with the simultaneous cooperation with engineering and other related specialists. Finally the study in summarized and future studies are prospected.

• Korean Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.274-282
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• 1998

A feature is a local shape of a product directly related to the manufacturing process. The feature plays a role of the bridge connecting CAD and CAM. In the process planning for he CAM, information on manufacturing is required. To get the a manufacturing information from CAD dat, we need to recognize features. Once features are recognized, they are used as an input for the process planning. In this paper, we thoroughly investigate the composite features, which are generated by interacting simple features. The simple features in the composite feature usually have precedence relation in terms of process sequence. Based on the reason for the precedence relation, we classify the composite features for the process planning. In addition to the precedence relation, approach direction is used as an input for the process planning. In the process planning, the number of set-up orientations are minimized whole process sequence for the features are generated. We propose a process planning algorithm based on the topological sort and breadth-first search of graphs. The algorithn is verified using sample products.

• IE interfaces
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• v.21 no.2
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• pp.221-228
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• 2008

The injection molding process is able to produce high precision manufactures as a single process with fast speed. However, the prices of both the mold and the molding machine are expensive, and the single process is very complex and difficult to compose of the exact relationship between the process setting conditions and the product quality. Therefore, the quality of a molded product often depends on a skillful engineer's operations in the design of both parts and molds. In this paper, the relationship between the process conditions and the defectiveness is built for better manufactures under settings of the appropriate parameters, and so it can reduce the setup time in the injection molding process. Quality Function Deployment (QFD) provides severe defectiveness factors along with the related process parameters. Also, neural networks estimate the relationship between defective factors and process setting parameters, and lead to reduce the defectiveness of molded parts.

• Environmental Engineering Research
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• v.25 no.4
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• pp.588-596
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• 2020

This study was carried out to increase the treatment efficiency through the improvement of the conventional biological process, and to propose the optimal treatment direction. The optimal treatment conditions were derived based on the results of the spike damage tests in each single process. The removal efficiency of micropharmaceuticals was further increased when an ozone treatment process was added to the biological process compared to the single process. The soil and activated carbon adsorption process was introduced in the post-treatment to remove the micropharmaceutical residues, and the removal efficiency of the pharmaceduticals in the final effluent was more than 85% in spike damage experiment. In particular, the continuous process of biological treatment-ozone-adsorption could ensure the stable treatment of micropharmaceuticals, which had not been efficiently removed in the single process, as it showed more than 80% removal efficiency. Therefore, it is expected that the addition of the ozone oxidation and activated carbon adsorption process to the existing sewage treatment facilities can contribute to the efficient removal of micropharmaceuticals.

• Journal of the Korea Safety Management & Science
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• v.6 no.3
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• pp.237-247
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• 2004

The condition of the manufacturing process in a factory should be diagnosed and maintained efficiently because any unexpected disorder in the process will be reason to decrease the efficiency of the overall system. However, if an expert experienced in this system leaves, there will be a problem for the efficient process diagnosis and maintenance, because disorder diagnosis within the process is normally dependent on the expert's experience. This paper suggests a process diagnosis using data mining based on the collected data from the coil-spring manufacturing process. The rules are generated for the relations between the attributes of the process and the output class of the product using a decision tree after selecting the effective attributes. Using the generated rules from decision tree, the condition of the current process is diagnosed and the possible maintenance actions are identified to correct any abnormal condition. Then, the appropriate maintenance action is recommended using the decision network.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.11-11
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• 2005

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.587-588
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• 2005

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.795-796
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• 2005

• Journal of the Korean Society of Systems Engineering
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• v.15 no.2
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• pp.31-38
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• 2019

The systems engineering standard process is intended to be customized for a given project environment and system characteristics. This study describes the experience gained by applying systems engineering to government-funded projects. The characteristics of government funded project are lack of common development process among the participating organizations and mechanism to determine system requirements. This study describes the contents of the systems engineering activities, including development of operational concept, system requirements, verification requirements (test cases), test verification plan, and implementation of system test and lessons learned from these activities.