• KSCE Journal of Civil and Environmental Engineering Research
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• v.39 no.6
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• pp.703-712
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• 2019

In this study, capability of an air slot in a siphon spillway for controlling outflow discharge is investigated through hydraulic experiments. Arc and rectangular shapes of air slot are considered and the open area of air slot can be varied. Complex air-regulated flow occurs inside of the siphon spillway when the air slot is installed on it. The same discharge is measured at the same water level inside the reservoir when the water level rises or falls. Nondimensional discharge through the siphon spillway decreases as nondimensional open area of the air slot increases when head differences and water levels of reservoir are constant. The hydraulic experiments show that the control of outflow discharge of siphon spillway is possible by controlling the open area of the air slot.

• The korean journal of orthodontics
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• v.25 no.6 s.53
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• pp.665-674
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• 1995

The purpose of this study is to investigate the cephalometric characteristics of the open-bite patients with DJD of TMJ. The DJD open-bite cases were compared with normal samples and Class II open-bite cases with normal TMJ respectively. Twenty three open-bite patients with bilateral DJD of TMJ($13.9\~35.3$ yens old, Group I) were selected from the Department of Orthodontics, SNUDH. Group ll consisted of thirteen Class II open-bite cases($13.2\~27.4$ years old) with no TMD signs/symtoms and good condylar shapes. Group III samples were the forty eight healthy dental students who have Class I molar relationships with no history of orthodontic treatment, good facial balance and no TMD symptoms($20.0\~26.8$ years old). First, sixty measurements in the lateral cephalometric radiographs and analysis of variance(P<0.05, Scheffe) were used to compare these three groups. The seven measurements showed significant difference(p<0.05) between Group I and Group II. After analysis of variance, six of them were used for the discriminant analysis(Wilks' stepwise analysis) and the discrminant function for Group I/Group II was obtained. The results and conclusions were as follows : In most of the measurments, Group I and Group II showed the same skeletal and dental characteristics. But seven of the sixty measurements(FH-PP angle, SNB, FH-ArGo angle, articulare angle, genial angle, upper gonial angle and Ar-Go length) were significantly different(p<0.05) between Group I and Group II. These differences may be explained by the fact that in DJD cases the mandible rotated backward due to the shortening of the ramus following the degenerative destruction of condylar head and its surrounding structures. The resulting discriminant function was : $D={-0.120X}_1+{0.066X}_2+{0.144X}_3-{0.058X}_4+2000,\;where\;X_1=ArGo\;length(mm),\;X_2=SArGo\;angle(degree),\;X_3=FH-PP\;angle(degree),\;X_4=Gonial\;angle(degree)$. Mean of the group centroids was -0.555 and percent of the 'grouped' cases correctly classified was $88.89\%$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.30 no.4
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• pp.634-639
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• 1997

In order to obtain the basic knowledges for the effective seed production of Perinereis aibuhitensis, sediment preference, burrow shape and behavior with in burrow were investigated in the laboratory. The highest value in both sediment preference and survival rate of P. aibuhitensis were shown at fine sand below 0.10 mm in the mean diameter. The worm made various types of burrows, such as J, L, O, Y and I shapes. Generally, only one individual inhabits in a burrow with head-up, but when excreting, it positions up-side down.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.30-36
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• 1984

An ultrastructural study on the mature spermatoBoa oi Cloptorchis sineitsis was carried out. For this study, the liver cukes were collected from the livers of rabbits and rats artificially infected with the metacercariae obtained from the fresh water fish, Pseudorasbora parve. Six-month old worms were used. The collected liver fiukes were washed with 0.85% saline solution and then immediately moved to cold 2% glutaraldehyde buffered with 0.1M Millonig's phosphate buffier (pH 7.4) . The materials were dissected into appropriate pieces in the fixative about 30 minutes after beginning of the fixation. Two hours later the materials containing the seminal receptacle were rinsed several times with the buffier and were secondarily fixed with cold, bugeyed 1% osmium tetroxide(OsO4) for 2 hours. The fully mixed tissue blocks Ivere dehydrated in a series of graded concentrations of acetone and were embedded in Epon 812 mixture. Thin sections obtained from LKB-5 ultramicrotome were stained with uranyl acetate and Reynold's lead citrate. Observations of the sections were carried out with JEM-100CX II electron microscope, In general, the mature sperm was long thread-like form with a sickle-shaped head. According to the longitudinal sectioned view of the sperm tail, the nucleus seemed to be spirally coiled and run a little far along the tail. The acrosome was not observed. The cytoplasm of the tail was biflagellated as usual in trematodes. Unlike other platyhelminth spermatozoa, the sperm tail of Clenorchis sinensis showed the ${\ulcorner}9+2{\lrcorner}$ in the microtubular arrangement. The mitochondria with poorly developed cristae were observed throughout the middle piece. The middle piece of the tail showed dull ladder or triangular shapes with the two flagella at the bottom. But, the principal piece of the tail was slightly flattened cylindrical shape with two aagella within the cytoplasm. The end piece was uniflagellated. It was not clearly identised whether the end piece was subdivided into two by aagellum or the lengths of the two aagella were different. The glycogen granules were rich in the cytoplasm throughout the lenght of the spermatozoa. These granules might be the energy source for the movement of the spermatosoa.

• The Research Journal of the Costume Culture
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• v.18 no.6
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• pp.1153-1164
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• 2010

The objective of this study is to analyze the coordination images seen in comprehensive fashion items and their features. This will be done from the viewpoint of both the creativity as well as functional characteristics of items and images. For the method of study, I explored the idea of "snood" style, analyzing its features of 42 pictures appearing from the 2006 S/S to 2010 F/W collection. It is important to note that "snood" style has the characteristics of both a muffler and turtleneck. With looping design connected at both ends, it can be placed around the neck or head, creating the image of wearing a hood. After having examined the selected data and pictures, one can largely divide the exclusive high-fashion image categories into three types: feminine, avant-garde, and finally, active & functional sportive image. First, the orthodox image is widely accepted by most as it has forever evolved within the original tradition of the practically functional muffler(scarf). Second, since the metamorphic image tends to lend itself to free ideas, you can wear a snood around the shoulders like a collar. Worn together with the same type of clothing, the snood can be seen as an effective suit. Third, the aim of image emphasis is to highlight certain points, or make some features more noticeable, as a means of possibly attracting more interest and attention. The image of snood arises out of the use of shapes, colors, and other accessory parts. As mentioned earlier, snood stands out as an independent item instead of just being an accessory to clothing. Its primary function as a style coordinator is emphasized in order to create more distinctive fashion images. Through this study, I thereby intend to provide fashion style data on the latest trends, and high-fashion codes of snood coordination.

• Applied Microscopy
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• v.35 no.4
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• pp.32-41
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• 2005

The sperm morphology of two Korean frogs, Rana catesbeiana and R. nigromaculata (Ranidae) was studied with the light microscope, scanning and transmission electron microscopes. Sperm heads of the R. catesbeiana and R. nigromaculata were long-cylinder shapes. In the total length of R. nigromaculata sperm ($51.2{\mu}m$) was longer than those of R. catesbeiana ($44.6{\mu}m$). Both R. catesbeiana and R. nigromaculata had the long head and principal piece, and short middle piece, but the neck was undeveloped. The axonemal structures contain a 9+9+2 arrangement of microtubules. The number of mitochondria in middle piece have less than mammalian sperm, which irregular surrounded the axone of the middle piece. In conclusion, R. catesbeiana and R. nigromaculata shared many similar features in sperm heads, neck, middle piece, and a site of mitochondria and axial structure, and it suggests that these species should be closely related.

• Journal of the Korean Society of Costume
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• v.62 no.4
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• pp.15-31
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• 2012

This study is intended to understand the styles, colors and color arrangements of costumes expressed on Kisan Kim Jun-geun's genre paintings of Joseon in the late 19th century. The paintings vary according to the status and gender of the person wearing the costume as well as the time period and different situations the person belongs to. Also, this study aims to examine the meaning and value of Kisan's paintings in terms of the history of Korean costumes. The result of this study are as follows: The basic and common attire for people of all status and class is the jeogori(jacket), baji(pants) for men and Banhoijang jeogori, chima(skirt) for women. Men wear Po(coat) that represents their status and age, and they put on various hats according to different weather conditions or work-skill even when in the same status and class. However, women wear the Baeja(vest), Durumagi(coat) and head-dresses when they are cold. Overall, the costume patterns and shapes that appear on Kisan's paintings show the same patterns and structures when compared to different data during the same time period. Thus, they provide useful information to help not only understand the changes of patterns and structures of costumes, but also the situations and emotions of the people of that time period. Moreover, it can be understood that various colors and color arrangements that reflect the situations and emotions of the late 19th century were used. This study that analyses the colors and color arrangements used in Kisan's genre paintings can provide the very basic and systematically arranged data to help understand the unique colors in Korea. These data can also provide important information to understand the use of dyes and pigments during that time. Therefore, Kisan's genre paintings are meaningful and valuable in terms of the history of Korean costumes for these are the data, from which we can review the costumes, colors and color arrangements in the years from 1890 to 1910.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.9
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• pp.1117-1125
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• 2013

A finite element based approach that can be used to investigate the plane-view shape and crop loss of a material during plate rolling is presented. We employed a three-dimensional finite element model to continuously simulate the shape change of the head and tail of a plate as the number of rolling passes increases. The main feature of the proposed model lies in the fact that the multistage rolling can be simulated without a break because the rolling direction of the material is reversibly controlled as the roll gap sequentially decreases. The material constants required in the finite element analysis were experimentally obtained by hot tensile tests. We also performed a pilot hot plate rolling test to verify the usefulness of the proposed finite element model. Results reveal that the computed plane-view shapes as well as crop losses by the proposed finite element model were in good agreement with the measured ones. The crop losses predicted by the proposed model were within 5% of those measured from the pilot hot plate rolling test.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.10 s.175
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• pp.174-185
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• 2005

This paper presents the design, fabrication, and testing results of a dual stage actuator system for a fine positioning of magnetic heads in magnetic disk drives. A novel rotary microactuator which is electrostatically driven and utilized as a secondary actuator was designed. The stator and rotor electrodes in the microactuator was revised to have the optimal shapes and hence produces much higher rotational torque compared with the conventional comb-shape electrodes. The microactuators were successfully fabricated using SoG(silicon on glass) processing technology, which is known as being cost-effective. The fabricated microactuator has the structural thickness of $45{\mu}m$ with the gap width of approximately $3{\mu}m$. The dynamic characteristic of microactuator/slider assembly was investigated, and its natural frequency and DC gain were measured to be 3.4kHz and 32nm/V, respectively. The microactuator/slider assembly was integrated into a HDD model V10 of Samsung Electronics Co. and a dual servo algorithm was tested to explore the tracking performance of dual stage actuator system where the LDV signals instead of magnetic head signals were used. Experimental results indicate that this system achieves the tracking accuracy of 30nm. This value corresponds to a track density of 85,000 track per inch(TPI), which is about 3 times greater than that of current hard disk drives.

• Journal of Fashion Business
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• v.3 no.4
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• pp.131-138
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• 1999

The purpose of this study is to measure Korean, Chinese and Chosunjok college women's body part sizes, and then, classify their body shapes according to the drop value(hip circumference-chest circumference) as well as their statures, and thereupon, comparatively analyze the statistical distribution of their major body part measurements and thereby, provide for some basic data useful to the development of quality fitting apparels exportable to China. The results of this study can be summarized as follows; Most of Korean and Chinese college women were found to belong to the body type of "N" body shape, while many of Chosunjok college women belonged to "H" body shape body type characterized by normal stature but small difference between hip and chest circumferences. The most prevailing body type of Korean and Chinese college women next to "N" type(65%, 51%) was "H" (23%, 35%), followed by "A" type(12%, 14%), while that of Chosunjok college women was "H" type (54%), followed by "N" (40%) and "A" type (6%). On the other hand, in terms of distribution of major body part sizes, there was found a wide difference between Chinese and Korean college women. Chosunjok college women had similar body part sizes to Korean college women's in such measurements as waist back length, shoulder-to-shoulder length, front interscye length, back interscye length, under-chest circumference and weight, while having simliar body part sizes to Chinese college women's in such measures as stature, arm length, waist front length, waist side-hip line length, crotch length, head circumference, neck-root circumference and waist circumference.