• 한국항공우주학회지
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• 제33권10호
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• pp.60-67
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• 2005

현대의 고성능 전투기는 한계받음각 내에서 적절한 조종성(Controllability) 및 안정성(Stability)을 확보하고 있어야 한다. 고받음각에서 항공기가 이탈에 진입할 수 있는 한계값은 항공기 형상설계에 직결되는 문제이다. 하지만 현대의 고성능 전투기는 전기식 비행제어계통(Digital Fly-By-Wire Flight Control System)을 사용하여 고받음각 제어법칙을 설계함으로써 한계값 내에서 항공기의 안정성을 보장하고 있다. 현재, T-50 세로축 고받음각 제어법칙에는 (+)한계받음각 이상으로의 비행을 제한하는 받음각 제한기(Angle of Attack Limiter)가 설계되어 있다. 그러나 (-)한계받음각 이상으로 비행을 제한하는 받음각 제한기는 설계되어 있지 않아, 조종사의 과도한 (-)세로축 기동에 대해 항공기가 이탈에 진입할 수 있다. 그리고 T-50 비행시험에서 PA에서 과도한 (+)세로축 기동 시, 받음각(Angle of Attack)이 현재 설계되어 있는 한계받음각을 초과하는 문제점이 발생하였다. 본 논문에서는 고받음각 제어법칙을 일부 수정하여 한계받음각 내에서 항공기의 세로축 조종성능을 향상시키고, 항공기 안정성을 확보할 수 있는 제어법칙에 관한 연구를 수행하였다.

• 한국의류학회지
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• 제26권1호
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• pp.133-143
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• 2002

The textile industry is petting increased effort to manufacture the value-added products that gives the differentiated characters at every level of fiber and fabric production. The color is an important element to be used strategically in order to push up the value-added design. The colors of apparel products have a close relationship with the skin colors of consumers and their preference colors. This study was carried out to cluster the skin colors of the Korean women into several similar skin colors and to analyze their preference colors by the classified groups. We measured the skin colors of 354 Korean women. With color spectrometer, JX-777, we measured 4 points of the body; cheek with removing cosmetics off, forehead, rear neck and arm on the interior part near elbow. All subjects had been shown with 40 color chips and answered the preference colors and preference colors of apparel. Data were analysed to classify skin colors using K-means Cluster Analysis and Duncan test, Frequency and Chi square test on the preference colors about the clustered 3 groups. In doing so, we used in SPSS Win 10 statistical package. Findings were as fellows: 1) The skin colors of the Korean women were clustered into YR, R, and Y skin colors. The majority of the subjects, 324 observations had YR skin colors and the subjects were classified into 3 kinds of skin color groups who had YR skin colors. 2) The average skin colors of total 324 subjects was 5.23YR 6.49/4.09 in Munsell Color System(MCS), 66.56 in L value, 10.53 in a value, and 20.67 in b value. 3) The average skin color of Type 1 was 7.98YR 6.24/4.14 in MCS, 64.10 in L value, 15.05 in a value, and 24.0 in b value. For Type 2 was 7.30 YR 6.56/3.28 in MCS, 67.24 in L value, 6.89 in a value, and 18.4 in b value, and Type 3 was 7.01 YR 7.20/4.38 in MCS, 73.53 in L value, L 16.04 in a value, and 24.87 in b value. 4) The average face color of total 324 subjects was 7.31YR 6.65/3.56 in MCS, 68.13 in L value, 9.53 in a value, and 20.18 in b value. 5) The average face color of Type 1 was 4.19 YR 6.92/5.05 in MCS, 70.78 in L value, 13.2 in a value, and 25.32 in b value. For Type 2 was 5.24YR 6.33/3.79 in MCS, 64.94 in L value, 9.84 in a value, and 19.08 in b value. Type 3 was 5.4YR 6.85/4.68 in MCS, 70.1 in L value, 11.73 in a value, and 23.92 in b value. 6) The difference of mean values between the clustered 3 skin color groups showed significantly different except the a value of neck and H value of cheeks and H value of foreheads. 7) All 3 groups showed that the most preference colors and the most preference colors of apparel was 5R 4/14. and their preference colors were much more than the preference colors of apparel.

• 농촌의학ㆍ지역보건
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• 제22권2호
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• pp.239-252
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• 1997

A questionnaire survey including stool examination for the parasite ova, skin test, and enzyme-linked immunosorbent assay (ELISA) of the liver fluke to find the factors related with the prevalence of the parasite infestation was done toward 118 residents living in three villages of Song-jung, Yi-jung, and Chim-gok of Okok-myun, Goksung County, South Cholla Province. The results are as follows : 1. The prevalence of Clonorchis sinensis ova by the stool examination was 46.6%. The sensitivity and specificity of skin test to egg-positive cases were 63.5% and 68.9%. The sensitivity and specificity of ELISA to egg-positive clonorchiasis were 100% and 34.9%. 2. The prevalence of Clonchiasis was higher in male than in female. 45~64 year old group was the highest among age groups, and the longer the duration of living in the present residence was, the higher the prevalence was shown statistically significantly (p<0.01). 3. The present drinker had higher prevalence of Clonorchiasis significantly than the past drinker or non-drinker, and the more the frequency of drinking the higher the prevalence was shown significantly (p<0.05). 4. Those who took raw fish had significantly higher than persons who didn't take it or take cooked fish(p<0.05) and prevalence showed the tendency to be increased as the frequency to take raw fishes increased significantly(p<0.05). 5. Those who had taken a raw sweet fish(Plecoglossus altivelis) or snake-headed fish(Ophicephalus argus) showed significantly higher prevalence of infection with liver fluke than persons who didn't take the raw fish. 6. While 56.4% of persons infected with Clonorchiasis answered that they were healthy, only 13.0% of the subjects were careful for their health, and 41.8% experienced tests to diagnose liver flukes before they were examined by this survey. 7. While 56.4% of infected persons thought the prevalence was high in their community, 54.0% were afraid to be infected, 47.1% thought the infection might destroy their health, 25.5% took treatment drugs, and 18.2% took raw fish continuously after treatment. The above results confirmed that Goksung area was highly prevalent in Clonorchiasis, so it was necessary to push effective preventive program against liver fluke infection together with the program to diagnose and treat existing infected persons.

• Journal of Community Nutrition
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• 제5권1호
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• pp.29-36
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• 2003

This study investigated the correlation of the physical measurements and the basic physical fitness of 158 female students in the city of Seoul. The average age of the subjects was 22.0 ${\pm}$ 0.13 years old, the average height was 160.9 ${\pm}$ 0.7cm and the average weight was 53.4 ${\pm}$ 0.6kg. The mean BMI (Body Mass Index) was 20.7 ${\pm}$ 0.2kg/㎡. The average muscle mass was 36.5 ${\pm}$ 0.3 and the average body fat percentage was 28.0 ${\pm}$ 0.4%. The basic fitness levels of the subjects were measured based on the evaluation chart of the Korea Health and Science Research Institution (1994). The subjects were divided into 3 groups based on BMI(Group I : BMI < 20, Group II : 20 $\leq$ BMI < 25, Group III BMI $\geq$ 25) and the correlation between BMI and physical fitness was assessed. 1) The muscle strength of the subjects was measured by their grip strength, among other tests. Groups 1 and 2 were evaluated as “su” (level 1) and group 3 was “woo” (level 2). 2) Endurance 1 was tested by push-ups, and while groups 1 and 2 were evaluated as “su” (level 1), group 3 was “ga” (level 5). This result did not suggest any significant relevance among the subjects. 3) Endurance 2 was tested by sit-ups : groups 1 and 2 were evaluated as “mi” (level 3) and group 3 as “yang” (level 4). Group 2 and group 3 showed a significant difference. 4) Instant power was tested by standing high jumps, and although there was a significant difference between group 1 and group 3, all of the subjects were evaluated as “ga” (level 5). 5) Flexibility was measured by how far the subjects could bend forward. There was no significant relevance between the groups and they were all respectively evaluated as “woo” (level 2). 6) Agility was tested with side-steps and all the subjects showed poor agility as “yang” (level 4). 7) Heart and lung endurance was tested by the step test, calculating the maximum oxygen intake with the Physical Energy Index (PEI) and using the numbers according to the evaluation chart. Group 1 was evaluated as “mi” (level 3) and groups 2 and 3 were “woo” (level 2). From these results, we could see the group III (obese group) had a tendency of lower levels in all the variables related to body fitness They showed significantly lower endurance assessed with time for sit-ups and instant power by the standing high jumps. (J Community Nutrition 5(1) : 29∼36, 2003)

• 폴리머
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• 제32권4호
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• pp.328-333
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• 2008

삼투압을 이용한 약물전달시스템은 소화관내의 물이 다공성막을 통하여 시스템 내부로 침투하면 시스템 내부에 있던 삼투압물질과 섞여 삼투압을 발생시키고, 이 삼투압의 힘으로 시스템 내부에 있는 약물을 시스템 외부로 일정한 속도로 방출하는 제제기술이다. 이러한 삼투압을 이용하여 상용화된 대표적인 제품으로 니페디핀을 모델약물로 한 타블렛제형인 Procadia $XL^{(R)}$(Pfizer)과 $Adalat^{(R)}$(Bayer)가 널리 상용화되어 있다. 이번 연구에서는 타블렛 형태의 삼투압정을 유동층코팅 기술을 이용하여 삼투성펠렛으로 제조하였다. 삼투성펠렛은 수팽윤성 고분자와 삼투염을 포함한 시드층, 모델약물인 니페디핀을 포함하는 약물층 그리고 약물의 방출을 조절할 수 있는 다공성막으로 구성되어 있다. 본 연구에서는 다공성막으로 사용되는 초산셀룰로오스(CA)와 $Eudragit^{(R)}$ RS의 구성비와 코팅두께에 따른 약물방출 거동을 확인하였으며, 다공성막의 구성물질인 CA의 비가 증가할수록 또한 다공성막의 코팅두께가 증가할수록 같은 측정시간 때에 약물의 방출이 낮게 나타남을 확인하였다. 약물방출 전후의 펠렛의 형태를 확인하기 위하여 SEM을 측정하였다.

• 산업경영시스템학회지
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• 제39권4호
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• pp.106-116
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• 2016

MTO (Make to Order) is a manufacturing process in which manufacturing starts only after a customer's order is received. Manufacturing after receiving customer's orders means to start a pull-type supply chain operation because manufacturing is performed when demand is confirmed, i.e. being pulled by demand (The opposite business model is to manufacture products for stock MTS (Make to Stock), which is push-type production). There are also BTO (Build to Order) and ATO (Assemble To Order) in which assembly starts according to demand. Lean manufacturing by MTO is very efficient system. Nevertheless, the process industry, generally, which has a high fixed cost burden due to large-scale investment is suitable for mass production of small pieces or 'mass customization' defined recently. The process industry produces large quantities at one time because of the lack of manufacturing flexibility due to long time for model change or job change, and high loss during line-down (shutdown). As a result, it has a lot of inventory and costs are increased. In order to reduce the cost due to the characteristics of the process industry, which has a high fixed cost per hour, it operates a stock production system in which it is made and sold regardless of the order of the customer. Therefore, in a business environment where the external environment changes greatly, the inventory is not sold and it becomes obsolete. As a result, the company's costs increase, profits fall, and it make more difficult to survive in the competition. Based on the customer's order, we have built a new method for order system to meet the characteristics of the process industry by producing it as a high-profitable model. The design elements are designed by deriving the functions to satisfy the Y by collecting the internal and external VOC (voice of customer), and the design elements are verified through the conversion function. And the Y is satisfied through the pilot test verified and supplemented. By operating this make to order system, we have reduced bad inventories, lowered costs, and improved lead time in terms of delivery competitiveness. Make to order system in the process industry is effective for the display glass industry, for example, B and C groups which are non-flagship models, have confirmed that the line is down when there is no order, and A group which is flagship model, have confirmed stock production when there is no order.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권7호
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• pp.80-89
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• 2015

Nitrate is on the most seriou pollutant encountered in shallow groundwater aquifer in agricultural area. There are various remediation technologies such as ion exchange, reverse osmosis, and biological denitrification to recover from nitrate contamination. Biological denitrification by indigenous microorganism of the technologies has been reviewed and applied on nitrate contaminated groundwater. In this work, we selected the site where the annual nitrate (NO₃⁻) concentration is over 105 mg/L and evaluated denitrification process with sampled soil and groundwater from 3 monitoring wells (MW4, 5, 6). In the results, the nitrate degradation rate in each well (MW 4, 5, and 6) was 25 NO₃⁻ mg/L/day, 6 NO₃⁻ mg/L/day, and 3.4 NO₃⁻ mg/L/day, respectively. Nitrate degradation rate was higher in batch system treated with 2 times higher fumarate as carbon source than control batch system (0.42M fumrate/1M NO₃⁻), comparing with batch system with soil sample. This result indicates that increase of carbon source is more efficient to enhance denitrification rate than addition of soil sample to increase microbial dynamics. In this work, we also confirmed that monitoring method of functional genes (nirK and nosZ) involved in denitrification process can be applied to evaluated denitrifcation process possibility before application of field process such as in-situ denitrification by push-pull test.

• 한국보건간호학회지
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• 제7권1호
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• pp.49-65
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• 1993

This study had conducted to push our society for getting some proper measures of the anti-drug abuse and adopting this study as a fundamental data for the school health education. Sample subjects were the 3rd grade of high school in Chungnam Province and the number were 1,014. The data had been collected on Dec. 3th-8th, 1990 according to the tool of Institute on Drug Abuse of Korea. And then Frequency and $x^2-test$ were need to analyse of data by SPSS-X program. The results of this study could be summarized as follows. 1. They had used 14 kinds of drugs: $70.1\%$ of the subjects students used alcohol, $69.2\%$ analgesics, $38.6\%$ cigarette, $15.0\%$ stimulants, $14.7\%$ antitussives, $11.2\%$ antithistamines, $8.9\%$ hypnotics, $7.1\%$tranquilizers, $4.2\%$ inhalants, $2.3\%$ marijuana, $1.4\%$ hallucinogens, $0.9\%$ cocaine, $0.6\%$ amphetamines, and $0.6\%$narcotics. The boys' drug using rate is higher than girls' except in analgesics and stimulants. 2. With respect to misbehaving, $43.0\%$ of the students said they had pop houses, $42.4\%$ adult video, $17.4\%$ unexcused absence from school, $11.0\%$ dangerous weapon, $9.1\%$ sexual intercourse, $70.1\%$ disappearance from home, 8.0% blackmail, and $6.0\%$ assault. In every kinds of misbehaving, the boys' misbehaving rate is higher than the girls'. 3. Almost every kinds of drugs have the students first used at the age of 15 through. 18. And $13.8\%$ of the students smoked every da·y and $1.7\%$ drank every day. 4. The frequency of the drug using such as cigarette (p<.01), marijuana (p<.05), cocaine (p<.05) and narcotics (p<.05) showed the stastically significant differences according to the religions of the subjects 5. The subjects who has complaints about someone use more drugs than the ones who doesn't, and who doesn't have any complaints about five elements have never used drugs such as marijuana, cocaine, amphetamines, narcotics, hallucinogens, and inhalants. 6. The drug using subjects have the more experiences of adult video, pop houses, and unexcused absent from school than the non-drug using ones. It means that the subjects who use drug were apt to do misbehaving more often than the ones who have never used them, and delinquent boys and girls use more drugs.

• 한국산학기술학회논문지
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• 제19권1호
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• pp.705-713
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• 2018

자동차용 볼 조인트는 현가계와 조향계를 연결하는 부품으로 두 요소 사이에서 조향을 위해 회전 운동 및 직선운동이 가능하도록 돕는 기계 부품이다. 본 연구의 대상은 중대형 픽업 트럭에 사용되는 볼 조인트이다. 각 단품으로는 스터드(Stud), 소켓(Socekt), 시트(Bearing), 플러그(Plug)로 구성되어 있다. 볼 조인트의 주요 구조적 성능으로는 풀-아웃 강도 및 푸시-아웃 강도를 고려해야 한다. 이 구조적 성능들은 정해진 기준을 만족해야 하며 이를 만족시키지 못하면 보다 큰 사고를 유발할 수 있다. 볼 조인트의 설계 요구조건 만족 여부를 확인하기 위한 방법으로는 실험과 시뮬레이션 방법이 있으나 실험은 많은 시간과 비용이 소요된다. 본 연구에서는 볼조인트의 구조적 성능 예측을 위하여 모델링 소프트웨어로서 솔리드웍스(Solid Works)를, 유한요소해석 소프트웨어로서 아바쿠스(Abaqus)를 사용하였다. 유한요소해석은 2D 축대칭 모델의 정적 해석을 이용하여 요구되는 구조적 성능을 구하였다. 볼 조인트의 제작 시 발생되는 불확실한 요소를 제작 공차로 가정하였으며, 이에 따라 구조적 성능에 영향을 미치는 치수 설계 변수를 사례 연구를 수행해 파악하였다. 그리고 제작 공차를 수준 별로 정의 한 후, 사례연구를 이용해 구한 유한요소해석 결과값과 실험값을 비교하였다.

• 대한치과교정학회지
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• 제23권1호
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• pp.75-88
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• 1993

Recent reports indicate that shorter etching times than 60 seconds can be adopted without affecting the bond strength and clinical disadvantages. The purpose of this in vitro study was to compare the shear bone strength and to measure depth of etch at different etching time length. One hundred and eight extracted bovine lower central incisors were embedded each in a tooth cup with cold-cure acrylic resin. The facial surfaces of the teeth were ground wet with 600-, 800-, 1000-, and 1200-grit Sic papers, and finally polished with a water slurry of extrafine silicon carbide powder, washed with tap water, and dried with hot air. Nine groups of nine prepared teeth were etched with a commercial($38\%$ phosphoric acid solution) for 0, 5, 10, 15, 20, 30, 60, 90, and 120 seconds, respectively, rinsed with tap water, and dried with hot air. One conditioned teeth from every group was selected randomly for the scanning electron microscopic examination, and the remaining eight teeth of the groups were used for measuring the push shear bond strength after bonding brackets and immensing them in the $36.5^{\circ}C$ water for 24 hours. Another nine groups of three teeth were used for measuring the depth of etch and surface roughness with a surface profilometer. after pieces of adhesive tape of 3mm inner diameter positioned on the ground enamel surfaces, and etched with the above mentioned. The data obtained form the above expeiments were analysed statistically with one way ANOVA and Dunkan's multiple range test with the $95\%$ confidence level. The results and conclusion of the study were as follows; 1. The results of shear bond strength for the given experimental etching times were not statistically different, but showed the tendency of decreasing shear bone strength after over 60 seconds etching times. 2. On the scanning election microscopic examination, it was observed that the morphological patterns of etched enamel surface for 5 to 20 seconds were similar and consitent, and those for 30 to 120 seconds showed increasing over-etched patterns depending on the length of etching times. 3. The depth of etch was increased almost proportionally by the length of etching times, but it was not associated with the shear bond strength. 4. The surface roughness increased depending on the length of etching times, but it was not associated with the shear bond strength. 5. This experiment indicated that proper etching time with $38\%$ phosphoric acid solution is in the range of 5 to 30 seconds.