• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.648-651
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• 2004

A vacuum system with ejector has been widely used because of its simple construction and easy maintenance. Ejectors are the main part of the vacuum system, of which designs determine the efficiency of vacuum system. The ejector with the capacity of 1.5 ton/hr steam consumption was designed and tested. The results showed that the tested values are satisfied with the designed specifications. Comparing with other ejectors designed by overseas specialist makers, it seems to have a good performance.

• CDE review
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• v.8 no.3
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• pp.40-51
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• 2002

Design and manufacturing (or production) must be closely interrelated. They should never be viewed as separate disciplines or activities. Each part or component of a product must be designed so that it not only meets design requirements and specifications, but also can be manufactured and assembled economically, ecologically and with relative ease. This approach improves productivity and allows a manufacturer to remain competitive. This broad view has become recognized as the area of design for manufacture and assembly(DFMA). Here the principles of the DFMA and their some examples are reviewed.

• International Journal of Aeronautical and Space Sciences
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• v.17 no.1
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• pp.109-119
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• 2016

When manufactured parts undergo large deformations during the manufacturing process, the global specifications of a part based on the concept of tolerance zone defined in the ISO 1101 standard [1] enable one to control the part's global defects. However, the extent of this tolerance zone is too large when the objective is to minimize local defects, such as hollows and bumps. Therefore, it is necessary to address local defects and global defects separately. This paper refers to the ISO 10579 standard [2] for flexible parts, which enables us to define a stressed state in order to measure the part by straightening it to simulate its position in the mechanism. The originality of this approach is that the straightening operation is performed numerically by calculating the displacement of a cloud of points. The results lead to a quantification of the global defects through various simple models and enable us to extract local defects. The outcome is an acceptable tolerance solution. The procedure is first developed for the simple example of a steel bar with a rectangular cross section, then applied to an industrial case involving a complex 3D surface of a turbine blade. The specification is described through ISO standards both in the free state and in the straightened state.

• Transactions of Materials Processing
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• v.18 no.1
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• pp.39-44
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• 2009

This paper is concerned with forming technology of an automotive front side member part with ultra high strength steel sheet of DP980. The forming technology considered in this paper is the draw & form type, which installs the upper pad and lower pad to produce the complicated shape of ultra high strength steel sheet. In order to produce sound product, comparison between form type and draw & form type and between draw type and draw & form type are investigated by FE-analysis. FE-analysis is carried out with commercial sheet metal forming analysis S/W, DYNAFORM. It was shown from FE-analysis that the draw & form type satisfied the required specifications such as the dimensional accuracy and soundness of automotive front side member part. The effectiveness of the analytical result was verified by the experiment. From this investigation, the draw & form type is proved to be able to supply useful forming technology in forming ultra high strength steel.

• Fire Protection Technology
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• s.18
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• pp.28-35
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• 1995

To survive in the 21C every nations in the World squeeze their intelligence. To our country, having a marvelous growth career in viewpoint of the economy, making efforts to renovate. Behind the breath of the economy a lot of law, regulations, standards of industry, and specifications are exists and the in-dustry controlled by these. Regretably in spite of surprising growth of our economy in a short period still keeps them old rules as they have been applies on our industry without change. In the part of the rife resistance standards, espacially for the fire door, needs grad-up much for the recently version compared with the other countries's. The rapid reshape of the world urges us be revolutionized in the part of the software, ie. these unchanged rules.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.10a
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• pp.23-34
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• 2006

In a oo dam at oo city of Gyeongbuk, severe damages have been occurred on lower part of dam due to heavy rainfall for several years. This caused significant impediment for maintaining its original function. This is considered as an excellent case for overall improvement of stability of dam system through successful investigation and construction work. This paper present comprehensive specifications that are generalized and used for securing stability of dams by quoting this example.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.716-719
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• 1995

Although design process is a creative work, it includes a lot of iterations. Statistics show that about 15 to 40 percent of the total design activity is spent on time-consuming retrieval of technical informations such as standard part, handbook, engineering equation,previous design and so on. On the other hand, product structure and parts specifications change with the design process, which also need to be traced accordingly. The BOM, design history, and all the relecant technical informations can be managed can be efficiently within a unified framework called configuration. This paper presents a prototype of a configuration manager which is a part of the engineering data management system for machine tools.

• Fashion & Textile Research Journal
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• v.13 no.6
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• pp.934-942
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• 2011

This study was intended to analyze conventional grading increments and methods for middle-age men's pants, and to suggest new grading guidelines that will enable to improve satisfaction with size and silhouette as a result of combining the concept of grading, which help maintain the ratio and proportion by sizes as one of ready-made apparel's advantages, with body form oriented and aesthetic approaches. In the apparel industry, the current sizing specifications and methods adopted by relevant companies, as well as the characteristics of body forms of men aged 35 to 55 years were comparatively analyzed to find out problems and ultimately to suggest their solutions or improvements. It was considered that as the conventional grading practices used in the industry were customary on the basis of the past experiences, it was required to take the body forms of target consumers into account and also, to reconsider the conventional grading methods. Analyses of sizing and specifications by brands show that 4 to 19 sizes including 82 or 84 as standard size have been produced. Since men's apparel has a large number of sizes with the large range of sizes, grading is critically important. As silhouettes depend on the distribution of grading rule values at each point of increment pattern in the main regions during grading, it is necessary to consider both size grading and form variations. To maintain an appropriate silhouette with keeping the angle of center back line of a pattern, it is desirable to set the ratio of side line part to center part from the crease line to approximately 3:7. It is required to diversify the values of grading rules according to different sizes and pattern regions in consideration for the body forms of key consumers. In addition, if the natural lines of designs and patterns for the width increments of waist circumference and hip circumference, the increments of hip width in pant's front and back panels, the ratio of grading rule values of the right and left sides of crease line, knee circumference, thigh circumference and so on are taken into account, grading will be satisfactory in the all aspects of size, silhouette and ratio.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.2
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• pp.45-51
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• 2008

The objective of this study is to develop an automatic object changer unit to improve processing problems existed in the conventional horizontal machining center. In order to perform this objective, a upward and downward traverse unit in which a unit that consists of a motor and reducer, chain and sprocket wheel, and upper and lower base employed in an automatic object changer unit performs sliding contact motion in a frame was designed. To achieve this design, constraint conditions for the upward and downward traverse unit first designed. Then, an operation mechanism was designed and that was introduced as a sum of kinetic energy for the sprocket wheel and upper and lower base based on the moment of inertia, which is the kinetic energy of the converted upward and downward traverse unit in the side of the reducer. In addition, The work required to rotate the converted upward and downward traverse unit in the side of the reducer by one revolution can be calculated using the sum of work that is required in the sprocket wheel and upper and lower base that is a part of the upward and downward traverse unit. Furthermore, the converted equation of motion in the side of the motor can be introduced using the equation of motion using the converted upward and downward traverse unit in the side of the motor. Then, Then, a proper motor can be determined using predetermined specifications employed in the motor and several parameters in the upward and downward traverse unit in order to verify such predetermined specifications. Also, a design of a horizontal traverse unit that performs sliding motion on a upward and downward traverse unit and simulation that verifies the results of this design are required as a future study.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.1
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• pp.10-18
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• 2022

Fishery sea anchor is widely used for many fishing vessels. However, standardization of the dimension and terminology of the fishery sea anchor has not been achieved, reducing the reliability of the performance and safety of the fishery sea anchor. Therefore, this study researches the reality of usage of fishery sea anchor and then attempts to suggest the development direction of the standard draft as basic data. As a result of the survey on the reality of usage show that various terms were used for each part of the fishery sea anchor (including the incorrect form of non-standard words derived from Japanese) and that the production of this product in the fishery sea anchor market was concentrated on one specific manufacturer. In addition, the main specifications of the fishery sea anchor are set and manufactured based on conventional experience without standards. In the field, there was no standardized drawing for fishery sea anchor and users had low awareness of the main specifications of fishery sea anchor. Therefore, this study suggested the following regarding the fishery sea anchor: standard terms for each part including Korean and English names and standard drawing of sea anchor. It is hoped that this study will contribute to research for the standardization of fishery sea anchor, which will increase in reliability and lead to increased interest in standardization in the fishery field.