• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.59.1-59.1
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• 2015

We present hydrodynamic simulations of gas clouds that inflowing from the disk to a few hundred parsec region of the Milky Way. Realistic Galactic structures are included in our simulations by thousands of multipole expansions that describe 6.4 million stellar particles of a self-consistent Galaxy simulation (Baba, Saitoh & Wada, in prep.). We find that a hybrid multipole expansion model with two different basis sets and a thick disk correction well reproduces the overall structures of the Milky Way. We find that the nuclear ring evolves into 240 pc at T~1500 Myr, regardless of the initial size. For most of simulation runs, gas inflow rate to the nuclear region is equilibrated as ~0.02 Msun/yr, and thus accumulated gas mass and star formation activity is stabilized as $6{\times}10^7Msun$ and ~0.02M/yr, respectively. These stabilized values are in a good agreement with estimations for the CMZ. The nuclear ring is off-centered to the Galactic center by the lopsided central mass distribution of the Galaxy model, and thus an asymmetric mass distribution is arose accordingly. The lopsidedness also leads the nuclear ring to be tilted to the Galactic plane and to precess along the Galaxy rotation. In early evolutionary stage when gas clouds start to inflow and form the nuclear ring, the z-directional oscillations of the gas clouds results in the twisted, infinity-shaped nuclear ring. Since the infinity-shaped feature is transient only for first 100 Myr, the current infinity-shape observed in the CMZ may indicate that the CMZ forms quite recently.

• Fashion & Textile Research Journal
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• v.20 no.3
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• pp.266-278
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• 2018

This study investigated the transformation of the Chanel jacket by looking at clothing design and constructional components. This study explored Chanel jacket's designs from 2001 S/S to 2016-17 F/W, and collected designs from Samsung Design Net and Vogue. The study used 690 designs with the following results. First, in the silhouette of the Chanel jacket, straight silhouette and hourglass silhouette had the most; in addition, in the length, hip line and under hip line were in order. Second, in case of collar and neckline, the form of a non-collar was the most and revealed the persistence of round neckline which is the basic style of a Chanel jacket. Third, in the shape of sleeves, the loose-fit straight sleeves, wide sleeves, and cocoon sleeves appeared most often. In method of closure, button, zipper were in order, and snaps or without closure appeared. Fourth, in the form of braids, various forms such as twisted yarns, leashes, or lace were used, and patch pockets were mainly used in pockets. Chanel maintains its original design by using various methods. Chanel tried to improve activity and functionality through silhouettes, lengths, necklines, and sleeves. The unchanging expression of the world of Chanel will continue to display and inherit future value. This study can provide Chanel's unique characteristics and new ideas that can transform their origins for jacket design.

• IE interfaces
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• v.21 no.4
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• pp.411-417
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• 2008

An impeller is a type of high-speed rotor that is used to compress or transfer fluid under high-speed and pressure at high temperatures. The impeller is composed of an axial hub and several blades attached along the hub. The weight and shape of an impeller must be balanced, because their imbalances can cause noise and vibration, which can lead to the breakage of the impeller blades during operation. Thus, the hub and blades of an impeller are commonly machined in a 5-axis NC machine to obtain qualified surfaces. The impeller machining strategy or process plan can not be easily obtained due to the complex, overlapped and twisted shapes of impeller blades. Skillful machining process planners may generate appropriate machining strategies based on their experiences and floor data. However, in practice most shop floor data for the impeller machining is not well-structured such that it does not effectively provide a process planner with information for machining strategies and/or process plans. This paper reports the development of a case-based machining strategy support system (CBMS) that employs case-based reasoning to obtain the machining strategy of an impeller by using the existing machining strategies of the shop floor. The CBMS generates impeller machining strategies through a stepwise reasoning process considering the similarity features between the blade shapes and machining regions. A case study is provided to demonstrate that CBMS can generate useful machining strategies facilitating process planners. The developed system can simulate the tool paths of impeller machining and runs on the web.

• Applied Biological Chemistry
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• v.50 no.4
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• pp.253-256
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• 2007

In an attempt to optimize the in vitro-regeneration conditions necessary for the genetic manipulation of tomato species, we examined 'Ailsa Graig' cultivar of Lycopersicon for regeneration ability. The basal medium used for callus formation and shoot regeneration was MS (MS + vitamin) supplemented with six combinations of zeatin 2 mg/l, zeatin 2 mg/l + IAA 0.1 mg/l, zeatin 2 mg/l + IAA 0.5 mg/l, zeatin 4 mg/l, zeatin 4 mg/l + IAA 0.1 mg/l and zeatin 4 mg/l + IAA 0.5 mg/l. When all conditions tested were considered, however, only zeatin 2 mg/l was shown to be the best in shoot regeneration. The morphological characterization from in vitro-cultured callus of Lycopersicon esculentum L. var. 'Ailsa Craig' was investigated with scanning electron microscope (SEM). The surfaces of in vitro-cultured callus had well-defined epidermal cell in condition of zeatin 2 mg/l, but those of different treatments were twisted. These results suggested that shape of callus was involved in efficiency of shoot regeneration in tomato 'Ailsa Craig'.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.241.2-241.2
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• 2014

We present highly transparent liquid crystal displays (LCDs) using hybrid films based on carbon nanomaterials, metal grid, and indium-tin-oxide (ITO) grid. Carbon based nanomaterials are used as transparent electrodes because of high transmittance. Despite of their high transmittance they have relatively high sheet resistance. To solve this problem, we applied grid and made hybrid conductive films based on carbon nanomaterials. Conventional photolithography processes were used to make a grid pattern of metal and ITO. To fabricate transparent conductive films, carbon nanotube (CNT) ink was spin coated on the grid pattern. The transparency of the conductive film was controlled by shape and size of the grid pattern and the thickness of CNT films. The optical transmittance of CNT-based hybrid films is 92.2% and sheet resistance is also reduced to $168{\Omega}/square$. These substrates were used for the fabrication of typical twisted nematic (TN) LCD cells. From the characteristics of LCD devices such as transmittance, operating voltage, voltage holding ratio our devices were comparable to those of pristine ITO substrates. The result shows that the hybrid conductive films based on carbon nanomaterials could be alternative of ITO for the highly transparent LCDs.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1235-1244
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• 1994

In this study, experimental results of the nucleate boling of wire-wrapped tubes are provided. Both water and R-113 were boiled. Solid stainless steel wires, stranded copper wires and stranded nylon wires were tested. Solid stainless wire is effective to enhance the boiling of water. The performance is approximately the same(or slightly better at certain conditions) as that of GEWA-T tubes. For the test range of wire diameter 0.6 $mm{\le}d{\le}2.6 mm$, the optimum gap width increases as the wire diameter increases. The maximum heat transfer coefficient was obtained for the 1.0 mm diameter wire, and it is 1.6 times larger than that of the GEWA-T at the heat flux of 20 $kW/m^{2}.$ Solid stainless wire is also effective to enhance the boling of R-113 at low heat fluxes. The performance of the wire-wrapped tube approaches that of GEWA-T. At high heat fluxes, however, the enhancement decreases. The reason may be attributed to the cavity shape and the high wettability of the refrigerants. Stranded copper or nylon wire is effective to enhance the boiling of R-113. The performance is approximately the same(or slightly better) as that of GEWA-T tubes. Maximum heat transfer was obtained for the stranded nylon wire, and it is approximately 1.4 times larger than that for the GEWA-T at the heat flux of 20 $kW/m^{2}.$ The reason may be atrributed to the favorable thermal environment in the restricted regions formed by twisted wires.

• Journal of Biosystems Engineering
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• v.35 no.6
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• pp.373-379
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• 2010

This study was carried out to develop a belt pick-up type one-row soybean cutter, using physical properties and production conditions of soybeans. The prototype soybean cutter consisted of 4 parts: cutting part, conveying part, collecting part, and travelling part. The prototype soybean cutter was designed to cut soybeans planted with a row spacing of 600 mm, and at a height of 30 mm from the bed bottom using a disk saw. Through various trials with different peripheral velocities of the disk saw and forward speed of the cutter, determined ranges of the peripheral velocity of the disk saw cutting soybeans stems were greater than 18.3 m/s. Spacing between pick-up belts (clearance) was in a range of 60~90 mm so that soybeans could be picked at heights greater than 25 cm, and the size and shape of the pick-up belt were determined the conventional manual harvesting method. The optimal ratio between the forward speed of cutter and the peripheral speed of pick-up belts were from 1 to 1.2 by theoretical analysis. the pick-up belts had a $35^{\circ}$ of tilted angle and $90^{\circ}$ of twisted angle to pick up soybeans safely from the plant input to the lower end of the belts and convey soybeans to the upper end of belts nearby a container. The soybeans at the rear container were dropped down on the soybean row with an interval. The effective field capacity of the prototype soybean cutter was 0.136 ha/h, reducing the working hour by 92% when compared with the manual cutting.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.85-95
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• 1984

This study was performed to investigate the intestinal parasites (especially cestoda) in the guts of Theragra chalcogramma in Korea. The cestode larvae collected were morphologically observed and measured, and at the same time, microscopical study was done with the section slides of the cestode larvae. They were identified on the basis of the descriptions by Schmidt and Yamaguti. The results obtained in this study are as follows: 1. The cestode larvae were identified as Khawia sinesis, Eulacistorhynchus chiloscyllius, Tentacularia coryphaenga, Pssudonybelinia odontasantha and Nybelinia Zingualis. These are new species reported in Korea. 2. The characteristics of Khawia sinesis are its scolex lacking loculi and broad, fat and fimbriate shape. Its neck is not separated from the body but a little constricted. 3. Eulacistorhynchus chiloscyzzius is characterized by fairly long and acraspedote scolex. The bulbs are long; retractor muscles are attached to bases of the bulbs. The two bothridia are oval or round in shape and lacking posterior notch. The tentacles are long and poeciloacanthus; double chainette present. 4. Tentacularia coryphaenea is characterized by its long craspedote and subcylindrical scolex. The bothridia are separated, without free borders and spinous. The tentacles are short, slender, armed with solid hooks in spirals, similar except the base of tentacle. The tentacle sheaths are not twisted. The bulbs are ellipsoidal. 5. Pseudonybelinia odontacantha is characterized by its craspedote scolex. The tentacles are inserted near anterior margin of bothridia and armed with hooks in spirals ascending left to right. The hooks are similar, throughout tentacle, with feeble curve and provided with a tooth-like protuberance on the ventral side. The bulbs are three times longer than its width. The posterior margins of bothridia have a pair of eversible ciliated pits; or fossettes. 6. Nybelinia lingualis is characterized by its short and craspedote scolex. The bothridia are separated, with free boarders. The tentacles are cylindrical, armed with solid and similar hooks in quincunxes.

• The Korean Journal of Food And Nutrition
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• v.19 no.4
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• pp.358-365
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• 2006

To study simultaneous water and solute transport kinetics during soaking in concentrated solution, the influence of the concentration and molecular weight of the solute(polyethylene glycol(PEG) and NaCl) in the soaking solution and the temperature on the water loss and solute gain rates were observed by using a model vegetable tissue(potato). When potato slices$(4cm{\times}4cm{\times}0.1cm)$ soaked in 60% PEG solutions, the water loss rate of the early phase decreased with increasing of the molecular weight of PEG from 200 to 6,000, while the final water loss increased with increasing the molecular weight of PEG and it reached to 80%. The cell wall of potato tissue was permeable to NaCl and PEGs of which average molecular weight is smaller than 400 but it was not permeable to PEG 600 and larger molecules. PEG which has average molecular weight below 600 induced plasmolysis and those above 600 induced cytorrhysis. The water loss rate of potato sample soaked in smaller molecular weight PEG solution was faster than those soaked in higher molecular weight PEG solution before cytorrhysis happened. The water loss rate was reversed after cytorrhysis happened. The volume change of potato within the first 60 minutes was larger in low molecular PEG solution but the final ratio of decreasing volume was larger in high molecular PEG solutions. In PEG 200 solution, the potato tissue was slightly shrinked without shape change. However, in PEG 4,000 solution, volume of potato was reduced significantly and potato tissue was twisted.

• Korean Journal of Plant Tissue Culture
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• v.27 no.2
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• pp.89-94
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• 2000

In order to induce the mutants of Gentiana axillariflora Leveille, nodes were cultured on Schenk and Hilderbrandt (SH) medium containing TDZ 2 mg/L, BAP 2mg/L, GA3 0.5 mg/L and 0.1 mg/L NAA and each mutagen of ethylmethanesulfate (EMS), colchicine, N-methyl-N-nitrosourea (MNU), and sodium azide (NaN$_3$) through filtration. Comparision of morphological characteristics and survival rate in each mutant plants differed depending on mutagen sources and their concentrations. When EMS were treated on nodes, the regenerated plants was thin and albino, regenerated shoots appeared 'erectoides type' and get twisted. The case of colchicine were treated on nodes, the survival rate was from 84% to 97% at ail concentration after 30days but the rate of survival was decreased about 50% at 200 $\mu$M after 60days. The treatment of NaN$_3$200 $\mu$M was not survived. The survival rate was extremely decreased in MNU treatment at 500$\mu$M, according to concentrations two types of leaf characteristic were obtained. Type I of leaf characteristic was modified from oblanceolate to oboid at leaf shape and type II of leaf characteristic was modified from light green to dark violet at leaf color. RAPD analysis was carried out to check the genetic modification of regenerated plants by mutagen treatments. Three polymorphic DNA fragments out of thirty-seven obtained by RAPDs were observed in regenerated plants using 5 decamer primers.