• Journal for History of Mathematics
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• v.26 no.2_3
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• pp.197-210
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• 2013

The late 18C Malthus studied population growth for the first time, Verhulst the logistic model in 19C and, after that, the study of the predation competition between two species resulted in the appearance of Lotka-Volterra model and modified model supported by Gause's experiment with bacteria. Instable coexistence equilibrium being found, Solomon and Holling proposed functional and numerical response considering limited abilities of predator on prey, which applied to Lotka Volterra model. Nicholson and Baily, considering the predation between host and parasitoid in discrete time, made a model. In 20C there were developed various models of disease dynamics with the help of mathematics and real data and named SIS, SIR or SEIR on the basis of dynamical phenomena.

• Korean Journal of Applied Biomechanics
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• v.18 no.1
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• pp.21-30
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• 2008

The purpose of this study was to investigate the variability to compare local dynamic stability via a linear and nonlinear analysis during walking. Twenty four elderly males, 12 healthy elderly and 12 patients with osteoarthritise walked on a treadmill for 100 consecutive strides. Lyapunov exponent and correlation dimension and coefficient variation were calculated for the kinematic parameters to determine the dynamic stability during walking. The linear measures indicated that the healthy elderly demonstrated significantly higher variability in the ankle joint displacement. The nonlinear analysis revealed that COD for the knee joint angle were higher in patient with osteoarthritise. There were no coincidence in results between linear and nonlinear techniques over two groups. In light of nonlinear analysis, it was concluded that patients with osteoathritise showed higher local instability during walking.

• The KIPS Transactions:PartB
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• v.9B no.1
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• pp.35-46
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• 2002

The EEG is a time series of electrical potentials representing the sum of a very large number of neuronal dendrite potentials in the brain. The collective dynamic behavior of neural mass of different brain structures can be assessed from EEG with depth electrodes measurements at regular time intervals. In recent years, the theory of nonlinear dynamics has developed methods for quantitative analysis of brain function. In this paper, we considered it is reasonable or not for ICA apply to EEG analysis. Then we applied ICA to EEG for big toe movement and separated the independent components for 15 samples. The strength of each independent component can be represented on the topological map. We represented ICA can be applied for time and spatial analysis of EEG.

• Journal of the Korean Geographical Society
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• v.34 no.5
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• pp.473-491
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• 1999

세균성 이질은 국내 제1종 법정 전염병으로 분류되어 관리되고 있는 질환으로서 1998년 이후 그 발병 사례가 급속히 증가하고 있다. 본 연구는 1999년 3월 부산시 사상구에서 집단 발병한 세균성 이질을 대상으로 하여, 각 환자들의 발병 시점과 장소의 분포패턴에 대한 지리학적 고찰을 목적으로 한다. 환자분포의 특징적 공간패턴과 그들의 시계열적 확산 양상 등을 탐색하기 위한 방법론은 보건지리학과 지도학 및 공간통계학에 기반을 둔 공간분석기법을 중심으로 설정하였다. 분석자료는 해당 지역의 수치지형도, 지적도, 인구 센서스 자료를 포함한 GIS 데이터베이스로 구축되었다. 인구분포를 감안한 밀도구분도를 바탕으로 개별환자의 위치자료와 동 단위로 집계된 자료를 자료의 형태에 따라 분석기법을 달리하였으며, 환자 발생 밀도, 상대적 위험지수 등을 지도화하여 역학자료의 시각적 통계적 분석을 수행하였다. 환자분포의 공간적 중심위치와 분산의 변화 등 기술적 통계분석과 함께 제1차 공간속성을 커널추정법으로 찾아보았다. 이와 더불어 ‘공간적 의존성’과 관련된 제2차 공간속성은 K-함수와 시뮬레이션을 통해 분석하여 군집성 등이 통계적으로 확인되었다. 본 연구를 통해 역학조사시 GIS의 활용사례가 제시되었으며, 모집단 인구를 고려한 확률지도 작성 기법과 다양한 데이터 가시화 방법, 그리고 시계열별 발생 환자들의 지리적 변이를 분석 하는데 따르는 문제들이 논의되었다.

• Korean Journal of Psychosomatic Medicine
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• v.9 no.2
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• pp.153-163
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• 2001

This study was attempted to investigate the discriminant validity of Korean version of Eating Attitude Test-26(KEAT-26) and to provide the sensitivity, specificity and efficiency according to cutting score, which may be useful to determine the optimal cutoff point on various purposes. The KEAT-26 was administered to 108 female patients with eating disorders, 179 female participants in body slimming center, 120 female athletic college students, 227 female college students, and 183 healthy normal women. Validity was tested by ANOVA and ROC curve analysis. The results revealed that the total score of the KEAT-26 showed a statistically significance between groups and that the score of the KEAT-26 of eating disorders group was significantly higher than that of the other groups in post hoc test. In comparison of the 4 subfactor score of the KEAT-26 between groups, significant differences in main effect within groups were found in all subfactors except factor IV. ROC curve analysis showed 80% of efficiency to discriminate eating disorders group from normal control group using cutoff score on maximum discriminant efficiency and 69% of efficiency to discriminate eating disorders group from high risk groups for eating disorders. Each cutoff score on maximum in efficiency was as follows ; 25 between eating disorders group and participants in body slimming center, 19 between eating disorders group and healthy normal woman, 23 between eating disorders group and athletic college students, 21 between eating disorders group and college students. Using 22(T score 65) of the KEAT-26 as the cutoff score, sensitivity was 54%, specificity was 84%, and overall efficiency was 80%. These results indicate that the KEAT-26 has a good discriminant validity in Korean population and also suggest that the KEAT-26 may be useful assessment tool to screen the disordered eating problems on clinical and epidemiological purposes.

• Proceedings of the Korean Society of Life Science Conference
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• 2000.12a
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• pp.20-26
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• 2000

호흡기계 및 소화기계에 감염된 전염성 바이러스에 대한 역학적 기초자료로 이용하고자 1999년 1월부터 12월까지 부산지역에서 분리된 전염성 바이러스의 특징과 계절적 발생추이, 환자의 성별, 연령별 발생에 대해 조사한 결과는 다음과 같다. 1. 1999년도 바이러스 가검물 2261건에서 분리한 호흡기계감염 바이러스 279건과 소화기계 감염 바이러스 83주를 분리하였으며, 이중 인플루엔자 바이러스 A형이 96주(29.6%), B형이 107주(33.0%)로 대부분을 차지하였다. 2. 1999년의 바이러스 분리의 성별 분포는 총 360명의 환자 중 179명(49.7%)의 남성 및 181명(50.3%)의 여성으로 비슷한 양상을 나타내었다. 이중 호흡기계의 경우 279명의 감염환자 중 남성이 130명(46.6%), 여성이 149명(53.4%)으로 여성의 감염율이 비교적 높았으나, 소화기계의 경우 83명의 감염환자 중 남성이 51명(61.4%), 여성이 32명(38.5%)으로 남성의 감염율이 거의 2배정도 높게 나타났다. 3. 1999년의 연령별 분포는 10세 이하의 어린이가 194명(59.9%)으로 대부분을 차지하였으며, 이중 인플루엔자 바이러스가 99명(30.6%)으로 가장 높은 감염을을 나타내었다 유행성이하선염 바이러스의 감염어린이 중에 $l1{\sim}15$세의 연령층이 15명으로(53.3%)로 가장 높게 나타났다. 4. 1999년 월별 감염율은 호흡기계 감염증 바이러스의 경우 1월부터 4월까지, 그리고 12월에 증가 추세를 보이면서 4월에 가장 높은 감염율을 나타내었다 소화기계 감염증 바이러스의 경우 9, 10, 11월을 제외한 모든 월별에 관찰되었으며, echo와 coxsackie 바이러스는 무균성 수막염 환자에서 하절기에 집중적으로 발생하였다. 동절기에 유행하는 설사 바이러스는 12월에 비교적 높은 양상을 나타내었다. 5. 인플루엔자 바이러스는 MDCK 세포에서, 아데노 바이러스와 유행성 이하선염 바이러스는 HEp-2 세포에서, 파라인플루엔자 바이러스는 Vero 세포에서, 그리고 echo, coxsackie B 바이러스와 장내 바이러스는 HEp-2, Vero, BGM 세포에서 뚜렷한 세포병변 효과를 나타내었다. 6. 분리한 바이러스는 전자현미경으로 관찰한 결과 인플루엔자 바이러스 A 형(HINI, H3N2)은 95nm, B 형은 70nm크기의 구형을 나타내었으며, 바이러스표면의 지질 이중층이 뚜렷하게 관찰되었다. 아데노 바이러스는 외피가 관찰되지 않았으며, nucleocapsid는 symmetry이고 크기는 71nm로서 바이러스 입자 표면에 icosaheral capsomer의 배열이 명확하게 관찰되었고, 파라인플루엔자 바이러스와 유행성 이하선염 바이러스는 외피가 있는 구형의 큰 viron으로180, 170nm 크기이었다. 7. Echo와 coxsackie B group 바이러스는 모두 외피가 없는 isometric 형으로 크기는 $30{\sim}45nm$ 이었고, enteric adeno 바이러스는 84nm 크기로서 외피가 없고, 입자 표면에 capsomer의 배열이 명확하게 관찰되었고, rotavirus는 크기가 70nm이며 외층 capsid 단백질과 내층 capsid 단백질이 두층으로 되어 있는 전형적인 수레바퀴 모양을 나타내었다. 이상의 결과로 보아 호흡기계 및 소화기계에 감염되는 전염성 바이러스는 연중 지속적으로 분리되고 있으며 전염성이 강하여 집단 발생은 일으키는 경우도 많고 최근 들어 유행성 이하선염과 흥역 바이러스의 발생률이 높은 추이를 나타내고 있지만 아직은 특이한 바이러스 치료제가 개발되어 있지 않았으므로 지속적인 대책과 아울러 장기적인 발생 가능에 대한 예방책을 흥보하여야 할 것으로 보이며 계속적인 바이러스성 전염병 유행예측조사 및 역학조사가 적극적으로 이루어져야 할 것으로 사료된다.

• Sijohaknonchong
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• v.44
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• pp.255-279
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• 2016

Ignominy are ashamed or that mind. It is noted that this article 'shame[恥]' will do for obtaining the social dynamics in some way in the literary aspect. To investigate this aspect, this article took the text produced on the basis of 'shame[恥]' to be analyzed. First, through the Sayuksin[死六臣]'s Sijo[時調], 'Shame[恥]' they have confirmed the room to go to form a sympathy by revealing without hidden. It is worth evaluating in common with these Sijo is that of justice or loyalty. But the parameters of evaluation described what people are rare. In this article, I saw the parameter to 'shame[恥]'. Second, through the Sijo created in the war of the middle age of Chosun Dynasty, I examined the aspect of 'anger' which sparked a shame[恥]. Thus shame[恥] is hard to change the world directly. However, the possibility that it can also be a psychological instrument was found to be sufficient. In conclusion, 'shame[恥]' is clearly greater tendency to dismiss as a private act of the heart. But, I understood that the negative region of 'shame[恥]' can be converted to positive region. At this time, The premise of 'shame[恥]' should always be oriented to justice.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.122-131
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• 2010

This paper introduces the concept of a virtual ecosystem and reports the following three mathematical approaches that could be widely used to construct such an ecosystem, along with examples: (1) a molecular dynamics simulation approach for animal flocking behavior, (2) a stochastic lattice model approach for termite colony behavior, and (3) a rule-based cellular automata approach for biofilm growth. The ecosystem considered in this study consists of artificial organisms and their environment. Each organism in the ecosystem is an agent that interacts autonomously with the dynamic environment, including the other organisms within it. The three types of model were successful to account for each corresponding ecosystem. In order to accurately mimic a natural ecosystem, a virtual ecosystem needs to take many ecological variables into account. However, doing so is likely to introduce excess complexity and nonlinearity in the analysis of the virtual ecosystem's dynamics. Nonetheless, the development of a virtual ecosystem is important, because it can provide possible explanations for various phenomena such as environmental disturbances and disasters, and can also give insights into ecological functions from an individual to a community level from a synthetic viewpoint. As an example of how lower and higher levels in an ecosystem can be connected, this paper also briefly discusses the application of the second model to the simulation of a termite ecosystem and the influence of climate change on the termite ecosystem.

• Tuberculosis and Respiratory Diseases
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• v.49 no.4
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• pp.412-420
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• 2000

Background : There is increasing concern in many countries about the problem of drug-resistant tuberculosis. Prevalence of primary drug-resistant tuberculosis is the optimal epidemiological indicator for long term monitoring of national tuberculosis control program. Our purpose was The purpose of our study is to assess clinical characteristics and socioeconomic status of patients with drug-resistant tuberculosis. Method : We studied 68 cases with drug-resistant Mycobacterium tuberculosis infection diagnosed at the Ewha Womans University Mokdong Hospital from March, 1995 to February, 2000. Results : Patients with primary drug-resistant tuberculosis(PDR) were younger (39.6$\pm$16.3 years vs. 48.2$\pm$16.5 years ; p<0.05), had more population of less than more were under the age of 40 years aged -group(62.9% vs. 36.4% ; p<0.05) and were more highly educated than those with acquired drug-resistant tuberculosis(ADR)(38.9% vs. 11.1% ; p<0.05). In patients with ADR, the rates of familial history of tuberculosis and living in a rented house residence in a rented house were increased higher than compared with to those of patients with PDR. Patients with ADR had more involved lobes(2.0$\pm$0.8 vs. 1.4$\pm$0.7 ; p<0.01) and longer treatment duration than those with PDR(18.3$\pm$7.2 months vs. 10.6$\pm$6.3 months ; p<0.05). Patients with ADR showed larger numbers of resistant were resistant to more number of drugs, lower hospitalization rate and higher rate of self-interruption of medication than those with PDR. In patients with PDR, mono-drug resistance was increased, whereas poly- and multi-drug resistances were decreased compared with those with ADR. Resistance to isoniazid was the highest among antituberculosis drugs, and resistance to isoniazid in patients with ADR was higher than that in patients with PDR(90.9% vs. 71.4% ; p<0.05). Conclusions : Patients with ADR were more likely to include more population be of lower socioeconomic class, and patients with PDR seem seemed to be young and socially active population. For control of drug-resistant Mycobacterium tuberculosis infection, proper isolation and prevention of patient with drug-resistant tuberculosis are needed.

• Korean Journal of Veterinary Research
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• v.1 no.1
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• pp.53-53
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• 1961

During the period from 1956 to 1959, a serological survey was conducted in au effort to assessing the incidence of brucellosis in various domestic animals in Korea. The following results were obtained. 1. Seventy-six dairy cattle which were imported in the year of 1956 had 9 positive reactors (11.84%). Of 1127 goats imported in 1956 and 1958, eleven(0.98%) were reactor animals. 2. In 1956, of 108 dairy cattle tested 10(9.25%) were reactors. In 1937 and 1958, a total of 155 dairy cattle examined hid ten (6.45%) positive reactors. In 1959, of 127 dairy cattle examined two were reactor animals. 3. In 1958 and 1959, 432 goats in some districts in Korea were subject to test for brucellosis and the test revealed five (1.15%) reactors. In 1958, 683 swine serum samples were examined and eleven (1.04%) were positive. In 1959, 1133 Korean cattle were tested and seven samples (0.64%) showed positive reactions. 4. In the month of July in 1939, 580 beef cattle in Cheju National Ranch and Branch were examined and 111 (19.13%) were found to be reactors. In October of the same year, 157 cattle, consisting of reactor and suspicious cattle groups, were tested, of which 71 samples reacted positive and 47 remained suspicious. 5. In December of the year of 1958, there occurred. an outbreak of brucellosis in a swine herd in the Sachon Branch Experimental Station. Seven serological tests on 438 swine serum samples were conducted, of which 122 (27.87%) were found positive. 6. Dairy cattle No. 33 and No. 35 which had been imported in 1956 and detected as highly positive, were examined for a prolonged period to follow the variation of antibody titers. A marked drop in antibody titer was seen two months after the initial test while the re-increase in titer was observer our months after the first examination.