• Korean Chemical Engineering Research
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• v.53 no.5
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• pp.597-602
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• 2015

Characteristics of continuous preparation of ZnO powder were investigated in a micro drop/bubble fluidized reactor of which diameter and height were 0.03 m and 1.5 m, respectively. The flow rate of carrier gas for transportation of precursors to the reactor was 6.0 L/min and the concentration of Zn ion in the precursor solutions was 0.4 mol/L, respectively. Effects of reaction temperature (973 K~1,273 K) and flow rate of micro bubbles (0~0.4 L/min) on the pore characteristics of prepared ZnO powder were examined. The optimum reaction temperature for the maximum porosity in the ZnO powder was 1,073 K within this experimental condition. The mean size of ZnO powder prepared continuously in the reactor decreased but the surface of the powder became smooth, with increasing reaction temperature. The injection of micro bubbles into the reactor could enhance the formation of pores in the powder effectively, and thus the mean BET surface area could be increased by up to 58%. The mean size of prepared ZnO powder was in the range of $1.25{\sim}1.75{\mu}m$ depending on the reaction temperature.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.7
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• pp.1285-1290
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• 2017

We prepared ITZO thin films with various thicknesses on glass substrates using RF magnetron sputtering and investigated electrical, optical and structural properties of the thin film. Sheet resistance of ITZO thin film showed a decreasing trend on the increase of film thickness, but its resistivity exhibited a substantially constant value of $5.06{\pm}1.23{\times}10^{-4}{\Omega}-cm$. Transmittance of ITZO thin film moved to the long-wavelength with the increase of film thickness. Figure of merit in a visible light and an absorption area of P3HT:PCBM organic active layer of the 360nm-thick IZTO thin film was $8.21{\times}10^{-3}{\Omega}^{-1}$ and $9.29{\times}10^{-3}{\Omega}^{-1}$, respectively. Through XRD and AFM measurements, it was confirmed that all the ITZO thin films have amorphous structure and the surface roughness of films are very smooth in the range of 0.561 to 0.263 nm. In this study, it was found that amorphous ITZO thin film is a very promising material for organic solar cell.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.9
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• pp.681-688
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• 2013

Several problems caused by inevitable increment of airplane have been issued. The most effective solution to solve the issues is considered as establishing appropriate Air Traffic Management (ATM) that reduces aircraft's delay at an airport and intensify the airport's capacity. The purpose of this paper is to produce the optimum aircraft schedules that maximize the aircraft throughput by smooth air traffic flow near terminal area of an airport In this paper, mathematical formulations of the scheduling problem are firstly specified. Based on the mathematical modelling, an Optimization-Based Flight Scheduler that provides the optimum flight schedules for arriving aircraft is developed by introducing the Mixed Integer Linear Programming(MILP) and the Genetic Algorithms(GA). With this scheduler, we calculated the optimum schedules to compare to real schedule data from an Incheon Airport. As a result, it is validated that aircraft throughput produced by the optimum schedule is much better than that of the schedule from the Incheon airport. The optimization-based flight scheduler is expected to deal with problems due to the aircraft saturation in near future.

• The Korean Journal of Physiology
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• v.18 no.1
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• pp.37-50
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• 1984

The effects of $Ca^{++}$ and its antagonists (verapamil and $La^{+++}$) upon the spontaneous contraction and the contracture induced by 60 mM K-Tyrode solution were studied in the isolated uterine muscle. Longitudinal muscle strips were prepared from the rat uteri at estrous stage. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% $O_2$ and kept at 35^{\circ}$. The results obtained were as follows: 1) In the uterine strips contracting spontaneously, both the amplitude of peak tension and the area of contraction curve increased dose-dependently in the range of $0.5${\sim}8$ mM $Ca^{++}$. The frequency of contraction increased as the concentration of $Ca^{++}$ increased up to 2 mM, but above this concentration the frequency decreased. In $Ca^{++}-free$ media, however, contraction did not develop. In the contracture induced by 60 mM K-Tyrode solution, the developed tension increased dose-dependently as the concentration of external $Ca^{++}$ increased to 8 mM. In the absence of external $Ca^{++}$ K-contracture appeared, but it was not sustained. 2) The spontaneous contraction of rat uterus was suppressed by verapamil in proportion to an increase of its concentration and totally abolished at the concentration of $3{\times}10^{-4}\;g/l$, but the spontaneous contraction re-appeared by addition of $Ca^{++}$. The amplitude of peak tension recovered completely but the recovery of frequency was incomplete. K-contracture decreased in a dose-dependent manner after the treatment with verapamil and totally disappeared at its concentration of $3{\times}10^{-4}\;g/l$. Even in this case contracture developed again by extra $Ca^{++}$. 3) The spontaneous contractile activity was inhibited by $La^{+++}$. At the concentration of $10^{-4}$M $La^{+++}$, fibrillation appeared. In the strip inhibited by $10^{-5}M\;La^{+++}$, contractility recovered completely by extra $Ca^{++}$ while in the $10^{-4}M\;La^{+++}$ treated preparation, the rhythmic spontaneous contraction did not develop even at the concentration of 16 mM $Ca^{++}$. After the initial transient depression of contracture tension by $10^{-3}M$ of $La^{+++}$, the strip stowed considerably large size of contracture, hardly influenced by external $Ca^{++}$ or verapamil. The results obtained in this experiment suggest that in the rat uterine muscle there would be some competitive actions between $Ca^{++}$ and its antagonists. It is speculated that $Ca^{++}$ plays an important role in the conduction of excitation, and $La^{+++}$ influences upon cellular $Ca^{++}$ mobilization and re-uptake process as well as transmembrane $Ca^{++}$ transport in a K-depolarized state.

• The Research Journal of the Costume Culture
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• v.12 no.3
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• pp.415-428
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• 2004

The purpose of this thesis was to develop torso patterns according to the physical types of men in 20s. The procedure and results are as follows; 1. Of the men in 20s meeting the national average of physique, 4 men were selected and classified into 2 physical types according to their chest and waist circumference drops. One group had 20㎝ drop (Y type) while the other had 16㎝ drop (N type). Through evaluation performed by clothing construction professionals on the 4 upper bodice blocks drafted according to the existent drafting method and dressed on the 4 men, several problems have been found. These problems were adjusted and supplemented to make two new blocks. The fit of the new blocks were evaluated and proved to be satisfactory. 2. The following is the adjustments made to the existent men's torso patterns which had been utilized as the objects the first evaluation experiment. ① Though the back waist length of the pattern from the existent drafting method covered the center back length of the body in both Y type and N type, the front length did not causing it to stand away from the body. To adjust this, 2.0㎝ has been added to the center front length of each pattern so that the waist line could make a bar level to the ground. ② The shoulder line of the pattern from the existent drafting method had the tendency to fall backward. To make the shoulder line to fall in place, it has been moved 1.0㎝ to the front. 0.5㎝ has been added to the should length. ③ The neckline had a tendency to climb up. It has been lowered by 0.5㎝ until the line touched the center front neck point. ④ Though different in degree, the neck circumference did not allow enough width for both physique type causing the neckline to pull at side neck point with diagonal crease. To adjust this, 0.3㎝ and 0.6㎝ has been added to the Y type and N type respectively so that the neckline would touch the side neck point and the neckline could naturally fall into its original position. ⑤ Though different in degree, there was not enough space at the armhole causing wrinkles around this area. Therefore, 0.25㎝ and 0.5㎝ has been added to the front and back of the armholes of the Y and N types respectively. The armhole was made 1.0㎝ deeper only for the N type. ⑥ 1.0㎝ in the front and 0.5㎝ in the back were added to the side scam for the Y type while 0.5㎝ in the front and 0.25㎝ in the back were added for N type. This eliminated the unwanted wrinkles to give the silhouette a smooth look.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.4
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• pp.731-736
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• 2008

Odontogenic keratocyst is classified as a developmental odontogenic cyst and is believed to arise from cell rests of the dental lamina. It accounts for 3% to 11% of all jaw cysts and they occur twice as often in the mandible as in the maxilla. Histologically, the cysts are lined by stratified, keratinizing, squamous epithelium. Daugther cysts or microcysts are often observed microscopically. The recurrence rate has been reported variously, but is known by its high recurrence rate. These lesions are more common in males than in females, occur over a wide age range and are typically diagnosed during the 2nd and 3rd decade. The diagnosis depends on the cyst’s microscopic features and is independent of its location and radiographic appearances. This cyst is a radiolucent lesion that is often multiloculated, has a smooth or scalloped border. The cyst is characteristically located in the body and ramus of the mandible, and often occurs in conjunction with an impacted tooth. This case report describes an odontogenic keratocyst on the lower right molar area of an 8-year-old girl. The cyst was removed under the general anaesthesia, and is being checked regularly for any recurrences.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.1
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• pp.152-157
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• 2004

Physicochemical characteristics of rice milled by newly designed abrasive milling machine were studied. Crude protein and crude lipid contents were 7.81∼8.50% and 1.07∼0.95%, respectively, and they showed a tendency to decrease with milling times. However, they showed higher values than that of polished rice. Major fatty acids of crude lipid were palmitic acid, oleic acid, and linoleic acid. Whiteness of tested samples was higher than brown rice but lower than polished rice. The remain rate of rice germ of four pass-through and polished one time sample (FPS) was 39.33%, and it was higher than that of polished rice (4.00%). One thousand grain weight of samples over than three pass-through was significantly different from brown rice (p<0.05). FPS had smooth surface similar to polished rice and it showed some residual rice germ by scanning electron microscopy. Sensory evaluation showed that the taste of three pass-through rice, four pass-through rice, and FPS was not significantly different from polished rice, whereas their color, odor, texture, and overall acceptability had lower score than polished rice but higher than brown rice. Therefore, we estimate that rice ground over three pass-through by newly designed abrasive milling machine might be a good source having nutritive value.

• The korean journal of orthodontics
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• v.28 no.3 s.68
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• pp.419-429
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• 1998

This study was carried out in order to study early histologic changes and repair reaction appling to extrusive force for 3rd premolar of adult dogs. After 1 week of extrusive force with elastic chain, one of dogs was sacrified and after 3 weeks retention period, another dog was sacrified. The paraffin sections of samples were stained with Hematoxylin - Eosin and Masson's Trichrome and were examed by light microscopy . The obtained results as follows 1. In Hematoxylin - Eosin and Masson Trichrome stain of control group , the periodontal ligament width was constant from apical third to cervical third of the root and periodontal fiber arrangement was horizontal or oblique in cervical third. oblique in middle third, oblique in apical third of root. in alveolar bone, smooth appearance was shown 2. In Group 1, all periodontal fiber arrangement was oblique toward tooth, and the periodontal ligament width increased Partially PDL was ruptured in apex. In MT stain, immature bone formation was seen at alveolar crest area. Active bone formation was observed along the one side of alveolus, and apical portion of pulp was involved with blood vessel rupture , vacuolization of pulp tissue and hyperemia 3. In Group 2, most periodontal ligament arrangement and PDL width was repaired and fiber density increased. In MT stain, mineralization of immature bone on the alveolar crest was progressed. In pulp, vacuole and hyperemia was diminished and fibrotic change was diminished 4. After 3 week periodontal ligament has more repair ability than pulp tissue. pulp was involved with vacuolization and fibrosis, so it takes more time for repair.

• Journal of Korean Medical Ki-Gong Academy
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• v.11 no.1
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• pp.144-172
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• 2009

objectives : This research aimed to study the similar effects between Jwahun and Sojucheon_practice, as both Induces to SooSengg-HwaGang(the coordination of water and fire). methods : 141 recipients of the survey was conducted in the Jwahun room of Korean medicine Hospital, which contained to body reaction between the moment of the Jwahun and after the Jwahun. And the result of them compared with the body's response of Sojucheon_practice results : 1. In a survey, 78% of the patients had responses that were sweating. The area sweating a lot in the survey is the face, abdomen, chest and was, in this order, the ratio was high. About feeling of warmth and coolness, survey of those who felt the warmth ratio was 79%, those who did not feel the coolness ratio was 77%, most of the responses were warm bodies. 46% of patients replied that feels warm in the belly. It said the fact that Jwahun directly to the lower body is to warm. 2. Symptoms of congestion of the head on the survey, 78% of investigators did not appeal. Other investigators were responding they were dizzy. Research on pain and itching, but no response was at 84%. Among the responses to the itchiness, itching perineum was 11% of the respondents. The rest was weak. 3. Associated with defecation in the survey, the investigators found that 33% of respondents said fart. Urine is 22% of respondents said. Abdominal reactions, 33% of respondents answered was taking a tone in the abdomen. In response to the whole body reaction, the most relaxing 39% of the respondents said, 22% of respondents replied that the body feel lighter. 4. After Jwahun, belly is warm and cathartic reactions were the most responsive. This said that Jwahun even after, in the lower abdomen lasting warmth as can be seen. Smooth bowel movements disproves the abdominal organs is a good move. It will also be seen in the same context of bowel movements, abdominal response when just doing Jwahun. conclusions : Jwahun activate the meridians and through the perineum stimulation induced imdokmaek(任督脈) SooSengg-HwaGang(水升火降) to enable the training and some Sojucheon can have similar effects.

• Journal of Environmental Science International
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• v.27 no.5
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• pp.281-289
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• 2018

The Korean environmental impact assessment(EIA) system, and explored ways to improve it as a more efficient and viable institution relevant to the demand of our time and conditions in study. The first problem this study identified is found in the fact that the party to write up the assessment report is itself the business operator or the one who is planning to work out the business plan. This structure translates into placing an order with an agent for EIA report. The reporting job may br subcontracted to the agent at a cost far below the rate specified in the 'Standard for Estimate of Agency Fee for Environmental Impact Assessment.' This practice also causes the vicious circle of producing a report that is written to justify the project or business in question or it leads to rough-and ready and poor documentation to minimize the time required. Second, in order to achieve the goal of the plan or business, which is the target of EIA, the local residents tend to ve regarded as an obstacle. This means elimination of the local people from participating in the EIA or their opinion being frequently ignored. This is the seed of distrust and hostility that sometimes provoke disagreements or fierce conflicts. The first proposal to improve these problem is to improve the factors that cause poor documentation of the assessment report as well as improve the understanding of the EIA system. This study proposes the following measures for improvement. The agency cost for EIA should be paid by the business operator or a third party that can ensure faithful implementation of the payment. A system should be established to verify transparent estimation of the agency cost. In order to enhance the professional quality of EIA agents, there should be implementation of qualification test for industrial engineer of related engineers in addition to the current EIA Qualification Test. The second proposal for improvement is to improve the citizen participation process by instituting a legal framework to make clear the purpose of the briefing session for local residents, which is held as a procedure of EIA, and to ensure more positive publicity during the stage of listening to the opinion of the local community. For a smooth and rational communication process, a moderator and a communicator of opinion, as is the case in a public hearing, could be instituted to clearly get the purpose of the briefing session across to the residents and to help to carry out the explanation and Q & A sessions according to the categories of the opinion of the residents. At present, the notification of the public inspection of the draft of the assessment report and briefing session for the residents is made on the newspaper and internet network. But some people have difficulty with access to this method of announcement. A higher participation rate could be secured if a legal provision is added to specify putting up placards in specific places such as the entrance to the place for the briefing session for residents or the building of administrative agencies of the area concerned.