• 한국정보과학회논문지:시스템및이론
• /
• 제29권6호
• /
• pp.340-345
• /
• 2002

본 논문에서는 기관위치설정 문제 중에서, 이차원 평면에 주어진 n개의 점들로 구성된 집합 P에 대한 이산 2-중심 문제를 다룬다. P의 있는 서로 다른 두 점을 중심으로 선택하는 데, P의 다른 점들은 두 중심 중에서 가까운 중심가지의 거리의 최대값과 두 중심 사이의 거리의 합이 최소가 되도록 선택하는 것이 목적이다. 본 논문에서는 Ο(n$^2$logn) 시간에 이산 2-중심을 구하는 알고리즘을 제시한다.

• 보건교육건강증진학회지
• /
• 제20권3호
• /
• pp.61-76
• /
• 2003

Substance abuse among teenagers has been spreading widely and become a serious social problem. However, teachers hardly realize its importance. Recently, substance abuse prevention programs show a tendency towards one time education. This study aims to research the effect of substance abuse prevention on high school students using the Life Skills Training Program. Two classes(36 students in the experimental group, 35 in the control group) at W High School in Daejeon were randomly sampled for this study from May to June 2002. Substance knowledge and attitude, problem solving, and assertiveness were examined as Pre and Post-Tests. The data was analyzed using frequencies, t-test, means, and covariance(ANCOVA). The results of this study were as follows； 1. Compared with the control group, substance knowledge in the experimental group was significantly improved(F＝176.317, P＝.000). And compared with the control group, substance attitudes in the experimental group were improved significantly.(F＝207.682, P＝.000). 2. Compared with the control group, cognitions to problem solving in the experimental group was significantly improved(F＝100.937, P＝.000). 3. Compared with the control group, assertiveness behaviors in the experimental group were increased significantly(F＝207.255, P＝.000). The study showed that Substance Abuse Prevention of High School Students was effective in improving substance knowledge and attitude, cognition to problem solving, and assertiveness behavior. Some suggestions based on the result are as follows； 1. Substance abuse preventive programs must be practiced properly and systematically with high school students in their regular classes. 2. Various preventive education programs must be developed for substance abuse where high school students can join in a community center, such as Community Welfare Center, Alcoholic Counseling Center, and Mental Health Center. 3. For the furthering of substance abuse preventive education, there must be continued research about not only students with problems of substance misuse and abuse, but also students without them. 4. There must be early determination of students with problems of substance misuse to be able provide school social workers with the opportunity for intervention.

• 대한지역사회영양학회지
• /
• 제20권1호
• /
• pp.61-72
• /
• 2015

Objectives: This study was performed to examine nutrition problems and causes/contributing risk factors. Methods: This study was conducted using data 1,863 adults visited Asan health screening & promotion center located in Seoul, Korea during May to June of 2013. We used Nutrition Care Process Model developed by the International Dietetics & Nutrition Terminology (IDNT). Results: The most frequent nutrition problem in male subjects was excessive alcohol intake. Men in fifties showed the highest rate of excessive alcohol intake among the age groups examined (22.4%). By comparison, the most frequent nutrition problem in women was inadequate protein intake. Women in fifties exhibited the highest rate of inadequate protein intake (22.5%). The most common contributing factors for these observations were a low preference for dairy products followed by high preference for alcohol and a deficit in food-and nutrition-related knowledge, regardless of the sex and age. The most common nutrition problem observed among the group diagnosed with hyperglycemia or hypertriglyceridemia or hyperuricemia or fatty liver was excessive alcohol intake (p < 0.001), whereas the group diagnosed with hyperglycemia or hypercholesterolemia showed significantly higher rate of inappropriate intake of carbohydrate (fructose) compared to the group not diagnosed with such disease conditions (p < 0.05). The group diagnosed with hypercholesterolemia, hyperuricemia and fatty liver showed significantly higher occurrence of inappropriate intake of fat (saturated fat) than the group free of such diseases (p < 0.001). The osteopenia group showed higher rate of inadequate protein intake (p < 0.001) and the fatty liver group with excessive energy intake (p < 0.001). Overall, the results suggest that there is a significant relationship between nutrition problems and health conditions found in groups diagnosed with a diverse array of medical conditions. Conclusions: Therefore, we strongly suggest that dieticians should implement nutrition interventions with people visiting health screening & promotion center based on nutrition problems and the contributing factors diagnosed by dietitions in order to prevent chronic diseases in this population.

• 대한수학회논문집
• /
• 제29권1호
• /
• pp.173-185
• /
• 2014

In the present paper, we consider an anomalous diffusion problem in two dimensional space involving Caputo time and Riesz-Feller fractional derivatives and then solve it by using a series involving bilateral eigen-functions. Also, we obtain a numerical approximation formula of this problem and discuss some of its particular cases.

• 대한영양사협회학술지
• /
• 제18권2호
• /
• pp.97-114
• /
• 2012

This study was performed to assess the nutritional status and hair mineral content of children with behavioral problems and compare the values with a gender, age-matched control group. The subjects were recruited from S elementary school children in Seoul, Korea. Students scored higher than 60 points were diagnosed with behavioral problems according to the Korean-Child Behavior Checklist. Nutritional assessment of the two groups (behavior problem group: male n=15, female n=24; $9.6{\pm}1.6$ years, control group: male n=16, female n=18; $9.5{\pm}1.9$ years) was performed using a nutritional survey and by measuring hair mineral contents. In the results, food frequency questionnaire analysis showed that the intakes of anchovy (P<0.05), soybean curb (P<0.01), radish (P<0.05), bean sprouts (P<0.05), spinach (P<0.05), carrot (P<0.05), pumpkin (P<0.05), lettuce (P<0.05), cabbage (P<0.01), apple (P<0.05), and milk (P<0.01) were higher in the control group than the behavior problem group, whereas intakes of ramyeon (P<0.05), cookies (P<0.05), and coke (P<0.01) were higher in the behavior problem group than the control group. Intakes of most nutrients such as plant-derived protein (P<0.05), fiber (P<0.05), plant-derived calcium (P<0.05), phosphorus (P<0.05), plant-derived iron (P<0.05), vitamin B2 (P<0.05), vitamin B6 (P<0.05), vitamin C (P<0.01), vitamin E (P<0.05), and folate (P<0.05) were significantly higher in the control group than the behavior problem group. Hair analysis showed that the levels of arsenic (P<0.05), mercury (P<0.001), uranium (P<0.05), iron (P<0.001), boron (P<0.01), and germanium (P<0.001) were lower, but the levels of phosphate (P<0.05), chromium (P<0.001), sodium (P<0.05), and sulfur (P<0.001) were higher in the behavior problem group than the control group. Conclusively, behavioral problems constitute a complicated condition in which nutritional factors may play major roles. However, it is still under investigation as to whether or not modification of dietary habits or nutritional supplementation can improve children's behavior, since symptoms require a broad understanding of the environmental and genetic interactions.

• 한국ITS학회 논문지
• /
• 제12권1호
• /
• pp.43-50
• /
• 2013

본 연구는 사고처리 지연으로 인한 피해를 최소화할 수 있는 고속도로 순찰대의 최적입지를 결정하는 것을 목적으로 한다. 이를 위하여 우리는 최단거리를 기준으로 서비스 관할구간을 할당하는 maximum covering 문제와 사고 빈도 가중 p-center 문제를 각각 구성하고, 두 문제를 해결하기 위하여 라그랑지안 완화 알고리즘과 Daskin의 휴리스틱 알고리즘을 적용한다. 제안된 모형들의 결과는 한국 고속도로의 사고자료를 기반으로 최대사고가중거리, 평균사고가중거리, 평균처리거리 등의 사고처리 서비스 수준 지표를 이용하여 현재의 순찰대 입지와 비교된다. 비교 결과를 통해 제안된 모형들은 10km 평균 접근거리와 약 10분의 평균 접근시간을 개선할 수 있음이 확인된다. 또한 현재의 입지를 고정시키고 서비스 관할구간만을 변경할 경우에도 서비스 수준이 개선될 수 있다. 본 연구에서 제시된 모형과 결과는 고속도로 사고처리 서비스 수준을 개선하는 데에 활용될 수 있으며, 또한 다양한 유형의 긴급시설 입지 결정이나 시간대별 사고자료에 기초한 유동적 관할구역 설정 등의 이론적 기반을 제공할 수 있을 것으로 사료된다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제10권9호
• /
• pp.4207-4222
• /
• 2016

In a P2P (Peer-to-Peer) VoD (video-on-Demand) streaming system, the nodes' load is an important factor which affects the system performance. In the system, some nodes may receive too many requests, which leads to overload. On the other hand, some other nodes may receive too few requests, which leads to low utilization. Therefore, designing a reasonable load balancing strategy is important. However, existing related studies cannot handle this problem effectively, because they don't have an efficient dynamic load information management mechanism, and they don't distinguish the difference of requests when transfer the nodes' load. In this paper, to manage the dynamic load information efficiently, we design a load management table for each node. Based on the load information, we propose a load balancing strategy which uses a request migration algorithm (LBRM). Through simulations, our scheme can handle the load imbalance problem effectively and improve the users' playback fluency.

• 디지털융복합연구
• /
• 제16권2호
• /
• pp.225-234
• /
• 2018

본 연구의 목적은 외국인 근로자의 음주동기, 문화적응 스트레스, 문제음주의 관계를 파악하고, 문제음주에 영향을 미치는 요인을 규명하기 위함이다. 연구방법은 G 시에 소재한 2곳의 조선소에 근무하는 외국인 근로자 120명을 대상으로 2016년 10-12월까지 설문조사를 실시하였다. 연구 결과 외국인 근로자의 위험음주는 39.2%로 나타났다. 외국인 근로자의 문제음주에 영향을 미치는 요인을 규명하기 위한 회귀분석 결과, 음주동기의 하위영역인 사교동기(${\beta}=.368$ p=.003)와 동조동기(${\beta}=.337$ p=.005)였고, 문화적응 스트레스 하위영역인 향수병(${\beta}=-.197$, p=.009)으로 문제음주에 대하여 약 39.5%의 설명력을 보였다(F=26.849, p=.000). 본 연구결과를 바탕으로 외국인 근로자들의 문제음주를 예방하기 위해서 음주동기와 문화적응 스트레스를 활용한 알코올 교육 프로그램 개발 및 적용이 필요하다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
• /
• pp.230-230
• /
• 2013

In amorphous or microcrystalline thin-film silicon solar cells, p-i-n structure is used instead of p/n junction structure as in wafer-based Si solar cells. Hence, these p-i-n structured solar cells inevitably consist of many interfaces and the cell efficiency critically depends on the effective control of these interfaces. In this study, in-situ plasma treatment process of the interfaces was developed to improve the efficiency of a-Si:H solar cell. The p-i-n cell was deposited using a single-chamber VHF-PECVD system, which was driven by a pulsed-RF generator at 80 MHz. In order to solve the cross-contamination problem of p-i layer, high RF power was applied without supplying SiH4 gas after p-layer deposition, which effectively cleaned B contamination inside chamber wall from p-layer deposition. In addition to the p-i interface control, various interface control techniques such as thin layer of TiO2 deposition to prevent H2 plasma reduction of FTO layer, multiple applications of thin i-layer deposition and H2 plasma treatment, H2 plasma treatment of i-layer prior to n-layer deposition, etc. were developed. In order to reduce the reflection at the air-glass interface, anti-reflective SiO2 coating was also adopted. The initial solar cell efficiency over 11% could be achieved for test cell area of 0.2 $cm^2$.

• Transactions on Electrical and Electronic Materials
• /
• 제6권1호
• /
• pp.1-5
• /
• 2005

Continued scaling of MOS devices requires the formation of the ultra shallow and very heavily doped junction. The simulation and experiment results show that the degradation of pMOS performance in logic and SRAM pMOS devices due to the excessive diffusion of the tail and a large amount of dose loss in the extension region. This problem comes from the high-temperature long-time deposition process for forming the spacer and the presence of fluorine which diffuses quickly to the $Si/SiO_{2}$ interface with boron pairing. We have studied the method to improve the pMOS performance that includes the low-energy boron implantation, spike annealing and device structure design using TCAD simulation.