• 한국기계가공학회지
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• 제18권6호
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• pp.98-105
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• 2019

In order to improve the fuel economy and dynamic behavior of automobiles, the weight reduction tendency of automobile parts is obvious. Also, in order to maximize assembly and maintenance convenience, various parts are integrated and modularized. Multi-piece methods require many manufacturing processes and become a factor of lowering the strength of parts. It is advantageous to overcome the disadvantages by integrally manufacturing to reduce the processing steps and ensure the strength of the parts. However, when it is necessary to process in a narrow space inside the part, it is impossible to process with the existing spindle. The angle head spindle is only a component of a machine tool, but it is a core part that requires high technology and is highly utilizable in products requiring high precision machining. Therefore, various and continuous studies needs for angle head spindles in areas such as vibration absorption, operational safety, excellent dimensional stability, and strength. In this paper, we propose an optimal design for angle head spindle by performing structural analysis and shape optimization for angle head spindle gear and case.

• 한국공작기계학회논문집
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• 제13권6호
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• pp.81-86
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• 2004

Generally, automotive cylinder head is manufactured by FCD45 material that is hard to cutting materials, and it needs the accurate machining tool fir higher output of engine. This paper is concerned with a study on TiN coated 6 edges reamer for improving machining accuracy of cylinder head guide pin. The reamer shape is changed from 4 edges to 6 edges for the improvement of machining accuracy. Also, TiN coating is applied to the improvement of surface roughness of cylinder head guide pin and tool life of 6 edges reamer. It is noted that 6 edges reamer are effective in controlling the dimensional accuracy and surface roughness as well as increasing tool life.

• 한국소음진동공학회논문집
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• 제14권11호
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• pp.1075-1082
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• 2004

This research demonstrates the shock response analysis of a head disk assembly subjected to a half-sine shock pulse in the axial direction. In case of disk analysis, the numerical method presented by Barasch and Chen is used. Galerkin method is used with mode shape by numerical method. Head-suspension system is modeled as the cantilever in order to get simulation results. Simulation results of HDA are calculated by Runge-Kutta method. Finally, shock responses of head and disk are analyzed according to the change of the rotating speed of the disk.

• 복식문화연구
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• 제8권6호
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• pp.915-929
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• 2000

As a result of research, the character of the general dress-costumes from the late 17th century to the early 18th century in Genre Paintings of DuSeo Yun and YoungSeok Cho is as follows. Firstly young women wore braided hair at the back of head and married women wore hair in the style of Unjeun-mori with Gache. The length of Jeogori (Korean traditional jacket) covered waistor shortened to waist length. The width of Jeongori was suitable, because side-seam line was straight or oblique as it comes into inner line. The width of Git was enough and Mokpan-git (shape of board) and Kal-kit (shape of knife) appeared, and sometimes used other color fabric. Sleeve was narrow and ostly folded up. Chima (Korean traditional skirt) used darker color fabric than Jeogori and the width of Chima was narrow and its length was short. Sokbaji (Korean traditional underpants) shown below were narrow and its end narrower. They were barefoot or they wore Hye (Korean traditional shoes) after putting on Beoseon (Korean traditional socks). Secondly general man's hair tie a topknot (sangtu) and put on headdres, 'Bang-lip', 'Mang-geon', hairband, 'Tang-geon' on head. The length of Jeogori became shorter from the line which covered hip to the line which covered waist. The width of Jeogori was suitable and sometimes it had a slit of side-seam line. The width of Git (neckand) was wide and the length of Git was long. 'Kal-git'appeared and it used other color fabric. The shape of sleeve was straight and narrow. They folded up their sleeves. They folded up their sleeves. They folded up their slack that look like 'Jam-bang-i'and the width of slacks was not suitable, and it was narrow. Baji (Korean traditional pants) were with or without knot, worn 'Hangjeon'(ankle band). They were barefoot and wore 'Hye'or 'Jipsin'(Korean traditional straw shoes). Thirdly a person of high birth or a low-ranked official put 'Yu-geon', 'Mang-geon', 'Gat', 'Tang-geon', 'Bok-du', 'Bok-geon', 'Whi-hang'on their head on a topknot. They wore 'Po (Shim-ui, Jick-ryeong'Jung-chi-mak, Do-po, etc)'on Baji and Jeogori. 'Po'was long and wide, it knot with 'Se-jo-dae'(string belt) or 'Po-baek-dae'(band belt). It had a slit of sideline and 'Mu'which had or had not or which were hard to confirm. The shape of sleeve was straight or very wide and its length was long. The width of Baji was wide and knotted with 'Hangjeon'and wore'Beoseon'and 'Hye'. Fourthly child's hair was short or knotted to the back of the head. The length of Jeogori reached waist line and its width was wide. It had a 'Jeogori'which had s slit of sideline. The shape of sleeve was 'Tong-su'(straight), and the length of sleeve was diverse. They put 'Baeja'on 'Jeogori'. The width of Baji was not wide. They wore them straight without or with knot, 'Hangjeon'. They were barefoot or put on 'Jipsin'.

• 대한안전경영과학회지
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• 제12권4호
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• pp.87-92
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• 2010

The mask-face interface design should consider the face shape to improve the half mask respirator's fit ratio. This study tried to design the mask-face interface using recent Korean face data. By using the data of 1536 men's 3D face scanning (Size Korea data), head clay mock-up was made and mask-face interface line was extracted from this head mock-up. Using this interface line, the half-mask prototype was made. According to the quantitative fitting test, the proposed mask was found to be well fitted (average fit-ratio > 100). The proposed method had two advantages. 1) The method could use massive head-related anthropometric data like Size Korea data. 2) The qualitative fit test (observation) could be conducted very quickly by fitting the prototype to the head mock-up. However, this method also had several limitations. 1) The head clay mock-up could be different according to the mock-up maker. 2) The average values of the head-related anthropometric data were used to make the head mock-up. Small and large size head mock-ups should be made and tested.

• 한국양식학회지
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• 제12권3호
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• pp.193-196
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• 1999

In order to obtain the basic data for the effective seed production of Ureshis unicinctus sediment preference, burrow shape and burrowing depth in sediment were investigated in the laboratory. The highest valus in both sediment preference and burrowing rate of U. unicinctus were shown at fine and (0.11~0.50mm in the mean diameter). U. unicinctus made various types of burrows, such as J, L, S and U shapes. Generally only one individual inhabits in burrow with head-up.

• 소성∙가공
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• 제26권2호
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• pp.79-86
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• 2017

In this study, the sheet metal forming process of the brake chamber head, which had a complex shape compared to the conventional head part, was investigated using finite element (FE) analysis. In order to prevent the forming failures such as necking and fracture, the multi-stage forming process was introduced. The forming process consisted of three steps: (1) first drawing, (2) second drawing, (3) final forming. Experimental and FE simulated results of the brake chamber head were compared, and the results showed that the required characteristics of the straightness and the wall thickness at each location were satisfied.

• 한국화재소방학회논문지
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• 제9권1호
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• pp.20-29
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• 1995

The sprinkler head is a component of the sprinkler system intended to discharge water for automatic detection and extinguishment of fires. On this study, thermal characteristic values affecting the sensitivity of the fusible alloy type sprinkler head were obtained and analyzed under heated air stream condition which had constant temperature and velocity. The experiment was carried out under the forced convection condition with both the conductive heat loss considered and neglected. The thermal characteristic values of the sprinkler head were obtained in accordance with the material and shape of the heat responsive element and the conditions of the main body.

• Journal of Mechanical Science and Technology
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• 제19권3호
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• pp.894-904
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• 2005

The flow structure inside the intake head greatly affects the working efficiency of a vacuum cleaner such as suction power and aero-acoustic noise. In this study, the flow inside intake heads of a vacuum cleaner was investigated using qualitative flow visualization and quantitative PIV (Particle Image Velocimetry) techniques. The aerodynamic power, suction efficiency and noise level of the intake heads were also measured. In order to improve the performance of the vacuum cleaner, inner structure of the flow paths of the intake head, such as trench height and shape of connection chamber were modified. The flow structures of modified intake heads were compared with that of the original intake head. The aero-acoustic noise caused by flow separation was reduced and the suction efficiency was also changed due to flow path modification of intake head. In this paper, the variations of flow fields for different intake heads are presented and discussed together with results of aerodynamic power, suction efficiency and noise level.

• 복식
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• 제55권3호
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• pp.69-80
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• 2005

The anatomical structure of the head and face are influenced by environmental factors. Therefore in this study we had undertaken to determine normal values of the head and face by 3D measurement in the 384 normal Korean male adults to find out craniofacial characteristics of Korean male adults by the age group. From the basic statistical data analysis, vertex-tragion and the length between the pupils were the longest in their twenties and grew shorter in elderly groups. According to the analysis of the craniofacial proportion, the head type of Korean male adults was short-headed. The statistically noticeable differences were found in the measurement of the left and the right sides of face in the age groups of 20, 30, 40, and 50. The results of the factor analysis of the age group showed two groups which were classified to 20, 40, 50 ages and 30, 60 ages. The order of factor analysis was as follows; the perpendicular length, the horizontal length, and the width (from highest).