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Estimation of the Expected Socio-economic Benefits of the Largescale Comprehensive Agricultural Development Project and Jointcost Allocation -In the Case of Kumgang Project Area- (대단위 농업종합개발사업의 사회경제적 기대편익 추정과 결합비용의 배분 -금강지구를 중심으로-)

  • Lim, Jae Hwan
    • Korean Journal of Agricultural Science
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    • v.23 no.1
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    • pp.159-176
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    • 1996
  • This study is aimed at reviewing the methods of joint cost allocation and allocating the joint cost of estuary dam with specially repect to Kumgang Large-scale Agricultural Comprehensive Development Project. Apart from the water resource development project propelled by Water Resource Development Corporation in connection with Law of Multipurpose Dam Development, the Largescale Comprehensive Agricultural Development Projects couldn't ins-titutionally be carried out cost allocation of common facilities, even though it were concerned with irrigation, municipal and industrical water supply, flood control, sightseeing and industrial zone development components. To decrease farmer's burden of the project costs and, operation and maintenance costs, the joint costs of common facilities like estuary dam included in agricultural development projects have to be allocated by suitable method as alternative cost-remaining benefit method and the analytical activity should be supported by revising the concerned laws as Rural Development and Promotion and, Rural Rearrangement conpatible with the law for multipurpose dam development. Kumgang Agricultural Comprehensive Development Project was selected as a case study for the estimation of socio-economic benefits by project components and joint cost allocation of the estuary dam. The main results of the study are as follows; Joint cost allocation and unit charges by components 1. The project area will be 25,554ha with total project cost of 624,860 million won including the estuary dam cost of 120,843 million won. The project costs were ex-pressed by 1994 constant price. 2. Total quantity of water was estimated 365 million tons which were consisted of 245 million tons for irrigation, 73 million tons for municipal water and 47 million tons for industrial water. 3. The rates of joint cost allocation were amounted to 34.2% for agriculture, 2.5% for sightseeing, 45.7% for transportation, 11.8% for M & I water supply and 5.8% for flood control respectively. 4. The unit financial charges by project components were estimated at 7.88 won per ton for irrigation, 16.11won for M & I water, 1,686won per vehicle one pass, 977won per Pyeong according to the capital recovery method. The financial charges using straitline method for depreciation were estimated at 7.88won per ton for irrigation, 9.12won per ton for M & I water, 624won per vehicle one pass for transportation and 331won per Pyeong for sightseeing area. 5. The unit economic charges by project components were estimated at 21.1 won per ton for irrigation, 15.2won for M & I water, 977won per vehicle one pass, 977won per Pyeong according to the capital recovery method. The economic charges using straitline method for depreciation were estimated at 11.72won per ton for irrigation, 8.61won per ton for M & I water, 331won per vehicle one pass for transportation. Policy recommendation 1. The unit operation and maintenance costs for irrigation water in the paddy field couldn't be imposed as the water resource cost untreated. 2. The dam costs including investment cost and O & M cost, as a joint cost, had to be allocated by each benefited components as transportation, M & I water supply, flood control, irrigation and drainage, and sightseeing. But the agricultural comprehensive project have been dealt as an irrigation project without any appraisal socio-economic benefits and any allocating the joint cost of estuary dam. 3. All the associated project benefits and costs must be evaluated based on accounting principle and rent recovery rate of the project costs and O & M costs should be regulated by the laws concerned. 4. The rural development and promotion law and rural rearrangement law have to be revised comprising joint cost allocation considering free rider problems. 5. The government subsidy for the agricultural base development project has to be covered all the project costs. In case of common facilities representing joint cost allocation problems, all the allocated casts for other purposes like transportation and M & I water supply etc. should be recovered for formation in investment fund for agricultural base development and to procure O & M costs for irrigation facilities.

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Evaluation of Avian Influenza and Newcastle Disease Virus Detection Kit using Field Samples from Domestic and Semi-domestic Birds (닭과 야생사육조류로부터 야외샘플을 사용한 조류인플루엔자와 뉴캣슬병 바이러스 검출 키트의 평가)

  • Rahman, Md. Siddiqur;Malek, Md. Abdul;Islam, Md. Alimul;Uddin, Muhamad Jasim;Ahasan, Md. Shamim;Chakrabartty, Amitavo;Sakib, Md. N.;Chae, Joon-Seok
    • Journal of Veterinary Clinics
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    • v.29 no.4
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    • pp.309-314
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    • 2012
  • The study was undertaken to evaluate sensitivity and specificity of rapid Avian Influenza (AI) and Newcastle Disease virus (NDV) combo antigen kits from field samples of domestic (broiler and layer chicken, native chicken) and semi-domestic (duck, goose, pigeon and quail) birds of Bangladesh. Samples were collected from naturally infected AI suspected domestic and semi-domestic birds of five different outbreak areas in Bangladesh. From each area two birds were selected for sampling, and from each bird three types of samples (tracheal, cloacal and oro-nasal swabs) were collected. A total of 210 field samples from a total of 70 birds were collected and tested using AI and NDV combo antigen rapid diagnostic kits in the study. All three different samples from a bird showed similar pattern of reaction. Out of 210 samples, 15 samples (5 birds), 63 samples (21 birds) and 27 samples (9 birds) were positive for AIV, NDV and both for AIV and NDV, respectively; whereas the remaining birds were negative for either AIV or NDV in this screening test. Among the five AIV positive, a layer chicken from wet market in Mymensingh, Netrokona, Gibandha and Kurigram and a native chicken from wet market in Kurigram area was positive to AIV. The semi-domestic birds are either positive to NDV or free from both AIV and NDV. This study revealed that the AIV and NDV rapid diagnostic kits could be effectively use to diagnose the respective virus in trachea, oro-nasal and cloacal samples simultaneously. AIV-NDV combo Ag test result clearly indicates that the test kit designed for AIV and NDV could diagnose the disease rapidly with less effort and higher scientific know how which could be used for the detection of AIV and NDV using field samples in large scale.

The Recipe Standardization and Nutrient Analysis of Aguyjjim (Local Foods in Busan) (부산향토음식 아귀찜의 표준조리방법 및 영양성분에 관한 연구)

  • 김상애
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.6
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    • pp.1142-1149
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    • 2002
  • This study was designed to standardize recipe and analyze the nutrients of Aguyjjim (stewed angler), a kind of native local foods in Busan. The results of this study are summarized as follows. The form of angler and its way to catch for a bait were recorded in Jasanobo, but the recipe was not written. While angler was used as manure or feed once, it was boomed for Aguyjjim since 80's, accredited as high-quality fish and protein-rich food. The standard recipe of Aguyjjim was prepared (through 3 times experimental cooking), being based on the recipe of cookbooks and restaurants. Then standard recipe was subjected to sensory evaluation. All sensory properties (appearance, smell, texture etc.) of Aguyiiim were evaluated as “like slight S, moderately”in hedonic scale. Energy per 100 g of the Aguyjjim was 89 kcal. It contained protein (10.7 g), fat (1.3 g), fiber (2.6 g), Ca (45 mg), Fe (1.3 mg) and so on. Amino acid is mainly comprised glutamic acid and aspartic acid. Free amino acid contents such as asparagine, glutamic acid, taurine were high. Fatty acid primarily consisted of unsaturated fatty acid like oleic acid, linoleic acid. Traditional foods are based on that of local foods. However, there has been little study looking into the recipes and nutritional value of local foods. Aiming at development of traditional food, the present study offered the standard cuisine of Aguyiiim that is a kind of local foods in Busan. In addition, it presented the composition of nutrients, amino acids and fatty acids. This data would be helpful for houses, restaurants and food service facilities to revive the local foods.

Study on the Combination of In-situ Chemical Oxidation Method by using Hydrogen Peroxide with the Air-sparging Method for Diesel Contaminated Soil and Groundwater (과산화수소를 이용한 현장원위치 화학적 산화법과 공기분사법(Air-sparging)을 연계한 디젤 오염 토양/지하수 동시 정화 실내 실험 연구)

  • Kim, Nam-Ho;Kim, In-Su;Choi, Ae-Jung;Lee, Min-Hee
    • Journal of Soil and Groundwater Environment
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    • v.11 no.6
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    • pp.8-17
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    • 2006
  • Laboratory scale experiments were performed to investigate the removal efficiency of the in-situ chemical oxidation method and the air-sparging method for diesel contaminated soil and groundwater. Two kinds of diesel contaminated soils (TPH concentration : 2,401 mg/kg and 9,551 mg/kg) and groundwater sampled at Busan railroad station were used for the experiments. For batch experiments of chemical oxidation by using 50% hydrogen peroxide solution, TPH concentration of soil decreased to 18% and 15% of initial TPH concentration. For continuous column experiments, more than 70% of initial TPH in soil was removed by using soil flushing with 20% hydrogen peroxide solution, suggesting that most of diesel in soil reacted with hydrogen peroxide and degraded into $CO_2$ or $H_2O$ gases. Batch experiment for the air-sparging method with artificially contaminated groundwater (TPH concentration : 810 mg/L) was performed to evaluate the removal efficiency of the air-sparging method and TPH concentration of groundwater decreased to lower than 5 mg/L (waste water discharge tolerance limit) within 72 hours of air-sparging. For box experiment with diesel contaminated real soil and groundwater, the removal efficiency of air-sparging was very low because of the residual diesel phase existed in soil medium, suggesting that the air-sparging method should be applied to remediate groundwater after the free phase of diesel in soil medium was removed. For the last time, the in-situ box experiment for a unit process mixed the chemical oxidation process with the air-sparging process was performed to remove diesel from soil and groundwater at a time. Soil flushing with 20% hydrogen peroxide solution was applied to diesel contaminated soils in box, and subsequently contaminated groundwater was purified by the air-sparging method. With 23 L of 20% hydrogen peroxide solution and 2,160 L of air-sparging, TPH concentration of soil decreased from 9,551 mg/kg to 390 mg/kg and TPH concentration of groundwater reduced to lower than 5 mg/L. Results suggested that the combination process of the in-situ hydrogen peroxide flushing and the air-sparging has a great possibility to simultaneously remediate fuel contaminated soil and groundwater.

The Effect of Home Rehabilitation Exercise Program of Home Stayed Chronic Hemiplegic Stroke Patients (재가 만성 뇌졸중 편마비 환자의 가정 재활운동 프로그램의 효과)

  • Roh Kook Hee
    • Journal of Korean Public Health Nursing
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    • v.16 no.1
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    • pp.77-94
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    • 2002
  • This study was a quasi-experimental study of nonequivalent control group pretest- posttest design to investigate the effect of home rehabilitation exercise program on the physical and psychological functions of home stayed chronic hemiplegic stroke patients. The data were collected during the period of May 20th to August 15th, 200l. The subjects for this study were 40 hemiplegic stroke patients with the experimental group consisting of 19 patients and the control group being composed of 21 patients. The patients selected for this study were: (a)living in J city who had been diagnosed with stroke and at home after being discharged from the hospital, (b) suffering from stroke for 6 months to 5 years, (c) without recognition disorder with the MMSE-K(Mini-Mental State Examination-K)score above 25, (d) below 2 on the modified Ashworth scale, (e)free from heart and pulmonary disease, (f)able to walk beyond 15 minutes for themselves, (g) not taking regular exercises. The program for the experimental group provided 8 weeks' home rehabilitation exercise, two times of group education during the first week and individual education and supportive care after the second week through home visiting and telephoning more than once a week. The amount of time spent on rehabilitation exercise by the experimental group was 35 to 50 minutes a day, three times a week. In order to understand the effects of experiment the two groups were compared and verified by measuring the physical and psychological functions of both groups. The data were analysed by $\chi^{2}-test$, paired t-test and unpaired t-test and ANCOVA through SAS/PC program. The results of the study were as follows: 1. In terms of physical variables: grip strength. lower extremity muscle strength, walking time, ADL and serum lipid levels 1) There was no significant difference in the unaffected and affected grip strength between the two groups, even though the unaffected and affected grip strength was more improved in the experimental group than in the control group. 2) There was no significant difference in the unaffected lower extremity muscle strength between the two groups, even though the unaffected lower extremity muscle strength was more improved in the experimental group than in the control group. There was no significant difference either in the affected lower extremity muscle strength between the two groups, even though the affected lower extremity muscle strength was more improved in the experimental group than in the control group. 3) There was significant difference in walking time between the two groups. Walking time was significantly reduced in the experimental group whereas it increased in the control group. 4) There was significant difference in ADL score between the two groups. ADL score was significantly increased in the experimental group, but it significantly decreased in the control group. 5) There was significant difference in serum total cholesterol level between the two groups. After experiment the serum T-C level became lower in the experimental group whereas it became sigficantly higher in the control group. 2. In terms of psychological variables: depression and self-esteem 1) There was no significant difference in the depression between the two groups, even though the depression showed constant in the experimental group, but it showed a significant increase in the control group. 2) There was no significant difference in the self-esteem between the two groups, even though the self-esteem showed some increase in the experimental group, but it significant decrease in the control group. As shown above, the results of 8 weeks' home rehabilitation exercise program for chronic hemiplegic stroke patients produced positive effects on walking time, ADL score and serum T-C level, shortening walking time, improving activities of daily living(ADL) and lowering serum total cholesterol level.

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Analysis of User′s Satisfaction to the Small Urban Spaces by Environmental Design Pattern Language (환경디자인 패턴언어를 통해 본 도심소공간의 이용만족도 분석에 관한 연구)

  • 김광래;노재현;장동주
    • Journal of the Korean Institute of Landscape Architecture
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    • v.16 no.3
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    • pp.21-37
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    • 1989
  • Environmental design pattern of the nine Small Urban Spaces at C.B.D. in City of Seoul are surveyed and analyzed for user's satisfaction and behavior under the environmental design evaluation by using Christopher Alexander's Pattern Language. Small Urban Spaces as a part of streetscape are formed by physical factors as well as visual environment and interacting user's behavior. Therefore, user's satisfaction and behavior at the nine Urban Small Spaces were investigated under the further search for some possibilities of application of those Pattern Languages. A pattern language has a structure of a network. It is used in sequence, going through the patterns, moving always from large patterns to smaller, always from the ones which create comes simply from the observation that most of the wonderful places of the city were not blade by architects but by the people. It defines the limited number of arrangements of spaces that make sense in any given culture. And it actually gives us the power to generate these coherent arrangement of space. As a results, 'Plaza', 'Seats'and 'Aecessibility' related design Patterns are highly evaluated by Pattern Frequency, Pattern Interaction and their Composition ranks, thus reconfirm Whyte's Praise of urban Small Spaces in our inner city design environments. According to the multiple regression analysis of user's evaluation, the environmental functions related to the satisfaction were 'Plaza', 'Accessibility' and 'Paving'. According to the free response, user's prefer such visually pleasing environmental design object as 'Waterscape' and 'Setting'. In addition to, the basic needs in Urban Small Spaces are amenity facilities as bench, drinking water and shade for rest.

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Impact Resistance Reliability of Sn-1.2Ag-0.5Cu-0.4In Solder Joints (Sn-1.2Ag-0.5Cu-0.4In 조성 솔더 접합부의 내 충격 신뢰성 평가)

  • Yu, A-Mi;Lee, Chang-Woo;Kim, Jeong-Han;Kim, Mok-Soon;Lee, Jong-Hyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.226-226
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    • 2008
  • 지난 10여년 동안 Sn-3.0Ag-0.5(wt%)Cu 합금은 대표 무연솔더 조성으로 다양한 전자제품의 실장 및 접합에 적용되어 왔으며, 그 신뢰성 역시 충분히 검증된 바 있다. 그러나 최근 Ag 가격의 급격한 상승과 솔더 접합부의 내 충격 신뢰성을 보다 향상시키고자 하는 업계의 동향은 Ag의 함량이 낮은 무연솔더 조성의 적용 확대를 유도하고 있다. 이에 따라 본 연구자들은 저 Ag 함유 무연슬더로 Sn-1.2Ag-0.5Cu-0.4In 조성을 제안한 바 있는데, 이는 Sn-3.0Ag-0.5Cu 조성 이상의 solderability를 가지면서도 그 금속원료 가격이 약 20% 가량 저렴한 특징을 가진다. 또한 열 싸이클링 (cycling) 테스트를 통한 슬더 조인트의 신뢰성을 평가한 결과, Sn-3.0Ag-0.5Cu에 크게 뒤떨어지지 않는 양호한 특성이 관찰되었다. 따라서 본 연구에서는 열 싸이클링 테스트와 더불어 최근 그 중요성이 지속적으로 커지고 있는 내 충격 신뢰성 평가 시험을 실시하여 개발된 4원계 무연솔더 조성의 기계적 특성을 기존 무연솔더 조성과 비교, 분석해 보았다. 각 솔더 조성은 솔더 볼 형태로 제조되어 CSP(Chip Scale Package) 상에 범핑 (bumping)되었으며, CSP를 PCB(Printed Circuit Board) 상에 실장하는 공정에서도 Sn-3.0Ag-0.5Cu 및 Sn-1.2Ag-0.5Cu-0.4In의 두 종류의 솔더 페이스트가 사용되었다. 본 연구에서의 내 충격 신뢰성 시험에는 자체 제작한 rod drop 시험기를 사용하였는데, 고정된 CSP 실장 board의 후면 부위를 일정한 높이에서 추를 반복적으로 자유 낙하시켜 급격한 충격을 주는 방식으로 실험을 실시하였다. 이 때 추의 무게는 30g, 낙하 높이는 10cm 였으며, 추의 낙하 시 측정된 board 의 휨 변위량은 약 0.7mm로 측정되었다. 사용된 CSP와 PCB 는 모두 daisy chain 방식으로 연결되어 있기 때문에 저항측정기를 사용한 간단한 실시간 저항 측정 방법으로 시험 이력에 따른 파단부의 발생 시점과 대략의 위치를 손쉽게 확인할 수 있었다. 솔더 조인트의 파단 기준 저항값으로 $1000\Omega$을 설정하였으며. 각 조건 당 5 개 이상의 샘플에 대해 평가를 실시한 후 그 평균값을 조사하였다. 시험 결과 제안된 Sn-1.2Ag-0.5Cu-0.4In 조성은 대표적인 저 Ag 함유 조성인 Sn-1.0Ag-0.5Cu에 비해서는 떨어지는 내 충격 신뢰성을 나타내었지만, 우수한 연성에 기인하여 Sn-3.0Ag-0.5Cu 조성에 비해서는 약 2 배 이상 우수한 신뢰성이 관찰되었다. 또한 CSP의 실장 시 Sn-3.0Ag-0.5Cu보다 Sn-1.2Ag-0.5Cu-0.4In 조성 솔더 페이스트를 적용한 경우에서 보다 우수한 내 충격 신뢰성을 나타내어 기본적으로 개발된 Sn-1.2Ag-0.5Cu-0.4In 솔더 페이스트가 Sn-3.0Ag-0.5Cu 조성의 기존 솔더 페이스트 보다 내 충격 신뢰성이 우수함을 검증할 수 있었다. 각 조성의 솔더 조인트를 $150^{\circ}C$ 에서 500시간 aging한 후 실시한 내 충격 신뢰성 평가에서는 모든 조성에서 그 신뢰성이 급감하는 경항을 나타내었으나, Sn-1.2Ag-0.5Cu-0.4In가 Sn-l.0Ag-0.5Cu보다도 그 상대적인 신뢰성이 우수한 것으로 관찰되었다. 이와 같이 aging 후 실시하는 충격시험은 가장 실제적인 상황과 유사한 조건이므로 상기의 실험 결과는 매우 고무적이었으며, 이에 대한 보다 면밀한 분석이 요청되었다. 마지막으로 파면 및 미세조직 관찰을 통하여 각 조성에서의 충격 파단 특성을 비교, 분석해 보았다.

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Difference in Isoproterenol-Stimulated Cyclic AMP Levels of Lymphocytes between the Subgroups of Depressive Disorders (우울장애 아형간에 Isoproterenol 자극후 임파구 Cyclic AMP Levels의 차이)

  • Bahk, Won-Myong;Jeon, Yang-Whan;Kim, Kwang-Soo;Sung, Yang-Sook
    • Korean Journal of Biological Psychiatry
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    • v.3 no.1
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    • pp.46-50
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    • 1996
  • This study was designed to examine the basal cyclic AMP levels and the $10^{-5}mol/L$ isoproterenol-stimulated cyclic AMP levels of lymphocytes, by which ${\beta}$-adrenoceptor function was shown, between to normal controls and 17 drug free patients(8 major depresive patients and 9 dysthymic patients), who were diagnosed by DSM-III-R. The severity of depression was assessed by Hamilton Rating Scale for Depression (HDRS). Cyclic AMP levels were measured by radioimmunoassay(double antibody). The results were as follows ; 1) HDRS score was significantly higher in major depressive patients($41.8{\pm}4.6$) than in dysthymic patients($24.0{\pm}4.2$)(p<005). 2) There was no Significant difference in basal cyclic AMP levels among normal controls($3.9{\pm}1.7pmol/10^6cells/10min$), major depressive patients($2.1{\pm}0.5pmol/10^6cells/10min$), and dysthymic patients($3.9{\pm}1.8pmol/10^6cells/10min$). 3) There was significant difference in net cyclic AMP levels($10^{-5}mol/L$ isoproterenol-stimulated cyclic AMP levels minus basal cyclic AMP levels) among normal controls($16.5{\pm}6.0pmol/10^6cells/10min$), major depressive patients($3.0{\pm}1.4pmol/10^6cells/10min$), dysthymic patients($10.9{\pm}4.4pmol/10^6cells/10min$)(p <005). 4) The net cyclic AMP levels were significantly correlated with HDRS scores in major depressive patients(${\gamma}=-0.8^6$, p<0.05), but not in dysthymic patients(${\gamma}=0.43$, p=0.25). In conclusion, we suggested that the dysthymic disorder might differ from the molar depressive disorder not only in the severity of depressive symptoms but also in ${\beta}$-adrenergic responsiveness of lymphocytes, which was regarded as a biological marker of depressive disorder.

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CHARACTERISTICS OF DETAINED DELINQUENT ADOLESCENTS AND VARIABLES RELATED TO THE REPEATED CRIME DURING 6 MONTHS AFTER RELEASE (구속된 비행 청소년들의 특성 및 석방 후 6개월간 재범여부와 관련된 변인)

  • Kim, Won-Sik;Koh, Seung-Hee;Koo, Yong-Jin;Kim, Hong-Chang;Suh, Dong-Hyuck;Chung, Sun-Ju
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.10 no.2
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    • pp.201-211
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    • 1999
  • Objectives:This study investigated the characteristics of detained delinquent adolescents and variables related to the repeated crime during 6 months after release. Methods:The socio-demographic and crime-related characteristics of 73 detained adolescents were evaluated by semi-structured interviews and police records, and the psychological characteristics of them measured by the MMPI. We also compared the characteristics between subjects with and without repeated crime during 6 months after release. Results:1) Most of detained adolescents had families with low socioeconomic status(77%) and broken families(48%). Sixty-six percent of them were dropped out of school. The most frequent crime pattern was theft(49%), and with accomplice(77%). Seventy-five percent of total subjects had the records of previous conviction. Of the previous convictions, seventy-eight percent was same with the present crimes. 2) Subjects with repeated crime during 6 months after release were younger and had higher T-score on Pa scale of MMPI than the subjects without repeated crime. More adolescents with repeated crime had broken families than those without repeated crime. They also showed the crime-related characteristics of higher percent of theft among crime patterns, higher incidence of previous conviction, younger age of the first crime, and shorter crime-free duration from the last to present crime. Conclusion:These results of present study suggest that the development and the persistence of adolescent delinquency would be resulted from interaction of factors of individual, family, school, and community. By the comparison between subjects with and without repeated crime, it was found that familial dysfunction, younger age at first crime, presence of previous conviction might be the risk factors for repeated delinquency. To prevent repeated crime of delinquent adolescents more effectively, early therapeutic intervention and the development of programs to help adaptation in school and community would be essential.

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Identifying Bridging Nodes and Their Essentiality in the Protein-Protein Interaction Networks (단백질 상호작용 네트워크에서 연결노드 추출과 그 중요도 측정)

  • Ahn, Myoung-Sang;Ko, Jeong-Hwan;Yoo, Jae-Soo;Cho, Wan-Sup
    • Journal of Korea Society of Industrial Information Systems
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    • v.12 no.5
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    • pp.1-13
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    • 2007
  • In this research, we found out that bridging nodes have great effect on the robustness of protein-protein interaction networks. Until now, many researchers have focused on node's degree as node's essentiality. Hub nodes in the scale-free network are very essential in the network robustness. Some researchers have tried to relate node's essentiality with node's betweenness centrality. These approaches with betweenness centrality are reasonable but there is a positive relation between node's degree and betweenness centrality value. So, there are no differences between two approaches. We first define a bridging node as the node with low connectivity and high betweenness value, we then verify that such a bridging node is a primary factor in the network robustness. For a biological network database from Internet, we demonstrate that the removal of bridging nodes defragment an entire network severally and the importance of the bridging nodes in the network robustness.

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