• Transactions of the Korean Society of Machine Tool Engineers
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• v.13 no.6
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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.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.11
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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.

• Journal of Aquaculture
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• v.12 no.3
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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.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.735-739
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• 2005

This paper presents a new system to estimate the head pose of human in interactive indoor environment that has dynamic illumination change and large working space. The main idea of this system is to suggest a new morphological feature for estimating head angle from stereo disparity map. When a disparity map is obtained from stereo camera, the matching confidence value can be derived by measurements of correlation of the stereo images. Applying a threshold to the confidence value, we also obtain the specific morphology of the disparity map. Therefore, we can obtain the morphological shape of disparity map. Through the analysis of this morphological property, the head pose can be estimated. It is simple and fast algorithm in comparison with other algorithm which apply facial template, 2D, 3D models and optical flow method. Our system can automatically segment and estimate head pose in a wide range of head motion without manual initialization like other optical flow system. As the result of experiments, we obtained the reliable head orientation data under the real-time performance.

• Journal of the Korea Safety Management & Science
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• v.12 no.4
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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.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.6
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• pp.1116-1133
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• 2016

This study examines the historical background of Goryeo and its relationship with Song and Yuan. In addition, it observes the shape of dress styles for the king, queen, officers, maids in waiting, and commoners after classifying them with a focus on the dress style of normal people appearing in Buddhist paintings. This study then investigates structures by tracing Goryeo's unique identity and its characteristic by a comparison and analysis of dressing style elements of Goryeo with Song and Yuan. The results shows that the Song's system was used exclusively for the dress style of the king and government officers of Goryeo after Goryeo's submission period by Yuan. There were no clear appearances of a Mongol style dress but only changes in head styles of cutting hair around the head and twisting the rest in a top down and long method. In addition, Song's style Bokgeon was shown by the king to his lower level officers. This was because the king and his officers of Yuan were in accordance with Song's system in officer's dress, hat and head style, armor, and horseback riding equipment. Second, there is doubt if they inherited a traditional form and style of the dress rather than followed the dress style of Yuan because the shape of Yuan's basic dress style Deel is very similar to the dress shape of early Buyeo people's Po in the $3^{rd}$ to $4^{th}$ centuries. Third, the shape of the Chaksu and Gung-go had been kept as it was in the dress style of ordinary men, and because the shape of the double collar had already appeared in the period of Samguk, which appeared in all classes of Yuan. There is no reason to adopt double collar shape that appeared. The general Pyeonbokpo of the country had to be influenced by Yuan. Forth, the dress style of queen and her maids in waiting were mentioned in documents; however, there was no shape of a dress like Boktag and Deel in the relics, which are the characteristic of Yuan's woman dress style. Fifth, the shape worn national style Yu and Sang had been kept in an ordinary woman's dress style; however, the two style system of high and lower class in Yuan's ordinary woman dress style appeared newly and is considered an influence of Goryeo.

• Fire Science and Engineering
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• v.30 no.3
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• pp.86-93
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• 2016

The effects of the shape of a drencher head on the flow characteristics and radiation attenuation of a water curtain, in order to prevent a fire spread, were experimentally studied. The distance (h) between the orifice exit and deflector and the diameter of deflector (D) were varied as the shape factors of the head, with the same orifice diameter (d). It was found that an increase in h leads to an increase in the water flow rate and spray angle. However, the change in the spray angle decreases with increasing D. Increasing D brings about a subtle increase in the water flow rate and a significant decrease in the spray angle. A larger value of D makes it possible to produce a flatter pattern of the water curtain, but reduces the uniformity of the droplets inside the spray angle. The mean droplet diameter decreases significantly as the operating pressure increases. However, the variation in the shape of the drencher head does not significantly affect the change in the mean diameter at the same operating pressure. Finally, it was found that the radiation attenuation afforded by the water curtain at the same operating pressure was affected by water flow rate and droplet uniformity, which were determined by h and D, respectively.

• The Research Journal of the Costume Culture
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• v.8 no.6
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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'.

• The KSFM Journal of Fluid Machinery
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• v.17 no.4
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• pp.30-39
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• 2014

The cross flow turbine is economical because of its simple structure. For remote rural region, there are needs for a more simple structure and very low head cross flow turbines. However, in this kind of locations, the water from upstream always flows into the turbine with some other materials such as sand and pebble. These materials will be damage to the runner blade and shorten the turbine lifespan. Therefore, there is a need to develop a new type of cross flow turbine for the remote rural region where there is availability of abundant resources. The new design of the cross flow turbine has an inlet open duct, without guide vane and nozzle to simplify the structure. However, the turbine with inlet open duct and very low head shows relatively low efficiency. Therefore, the purpose of this study is to optimize the shape of the turbine inlet to improve the efficiency, and investigate the internal flow of a very low head cross flow turbine. There are two steps to optimize the turbine inlet shape. Firstly, by changing the turbine open angle along with changing the turbine inlet open duct bottom line (IODBL) location to investigate the internal flow. Secondly, keeping the turbine IODBL location at the maximum efficiency achieved at the first step, and changing the turbine IODBL angle to improve the performance. The result shows that there is a 7.4% of efficiency improvement by optimizing turbine IODBL location (open angle), and there is 0.3% of efficiency improvement by optimizing the turbine IODBL angle.

• Journal of the Society of Naval Architects of Korea
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• v.49 no.1
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• pp.6-13
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• 2012

As ocean resources in shallow water areas are being exhausted, deep sea development is becoming common these days. Therefore floating type offshore structures are more competitive than fixed type structures, and FPSO is the most popular one these days. FPSO's are generally operated in a specific region and positioned to meet mostly head or bow waves in order to reduce roll motions. However this makes these vessels more vulnerable to green water around the bow region, and therefore the bow shape must be properly designed to mitigate green water damage. In the present study, experimental results for three different FPSO bow shapes in regular head waves were analyzed and compared to each other. Also CFD computations were carried out as a sample validation case for the database built for CFD code validation.