• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• 제25권1호
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• pp.28-36
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• 2014

Objectives : The goal of this study was to examine the association between zinc and lead level and symptoms of attention-deficit hyperactivity disorder (ADHD) among Korean children. Methods : A total of 89 clinic-referred children participated in the study (ADHD group=45, control group=44). The participants were 5-15 years old, and were mainly from urban areas of Seoul, Korea. ADHD was diagnosed using the Kiddie-Schedule for Affective Disorders and Schizophrenia-Present and Lifetime Version. We excluded children with a comorbid psychiatric disorder, medical illness requiring medication, or a prior history of taking ADHD medication. In order to evaluate the severity of ADHD symptoms, parents' Korean ADHD Rating Scale (K-ARS) was used. The ADHD diagnostic system (ADS) was used for evaluation of the severity of inattention and impulsivity. All participants completed the intelligence test and hair mineral analysis. Multiple regression analysis was used to examine the effect of hair zinc and lead levels on the K-ARS and ADS. We measured the predictive ability of the zinc and lead levels using logistic regression analysis. Results : The lead level explained the score for omission errors, commission errors, and response time SD in visual ADS in the ADHD group (adjusted $R^2$=.243, p<.01, adjusted $R^2$=.362, p<.01, and adjusted $R^2$=.275, p<.01), the score for omission errors of auditory ADS in ADHD group (adjusted $R^2$=.407, p<.01) and the entire group (adjusted $R^2$=.292, p<.01). Zinc was significantly explanatory for the K-ARS scores for the entire group (adjusted $R^2$=.248, p<.001) and the ADHD group (adjusted $R^2$=.247, p<.05). Conclusion : These findings suggest a possible role of zinc and lead in ADHD. Lead concentration in hair samples affected the ADS scores, and this was more prominent in children with ADHD. Children with ADHD had a lower zinc concentration in their hair, and the zinc concentration in hair showed negative correlation with the K-ARS score.

• 한국산업보건학회지
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• 제25권1호
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• pp.45-57
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• 2015

Objectives: This study aims to compare the physicochemical characteristics, toxicological data with Occupational Exposure Limits (OELs) of chemicals under the Occupational Safety and Health Act(OSHA) regulated by the Ministry of Employment and Labor of Korea. Methods: Information on chemicals which have OELs on physicochemical characteristics and toxicological data was collected using Material Safety Data Sheet(MSDS) from Korea Occupational Safety and Health Agency(KOSHA) and the Korea Information System for Chemical Safety Management(KISChem) in 2014. Statistical analyses including correlation and simple regression were performed to compare the OELs with chemical characteristics including molecular weight, boiling point, odor threshold, vapor pressure, vapor density, solubility and octanol-water partition coefficient(OWPC) and toxicological data such as median lethal dose($LD_{50}$) and median lethal concentration($LC_{50}$). Results: A total of 656 chemicals have OELs under OSHA in Korea. The numbers of chemicals which have eight-hour time weighted average(TWA) and short term exposure limits(STEL) are 618 and 190, respectively. TWA was significantly correlated with boiling point and STEL was only correlated with vapor pressure among physicochemical characteristics. Solubility and OWPC between "skin" and "no skin" substances which indicate skin penetration were not significantly different. Both $LD_{50}$ and $LC_{50}$ were correlated with TWA, while the $LC_{50}$ was not with STEL. As health indicators, health rating and Emergency Response Planning Guidelines(ERPG) rating as recommended by the National Fire Protection Association(NFPA) and American Industrial Hygiene Association(AIHA) were associated with OELs and reflect the chemical hazards. Conclusions: We found relationships between OEL and chemical information including physicochemical characteristics and toxicological data. The study has an important meaning for understanding present regulatory OELs.

• 한국수자원학회논문집
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• 제53권1호
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• pp.45-56
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• 2020

본 연구는 SWAT-CUP을 이용한 SWAT 모형 매개변수 보정을 수행할 때, 목적함수로 인해 발생할 수 있는 불확실성을 정량화하는 것을 목표로 수행되었다. 먼저 낙동강 권역의 내성천 유역을 대상으로 유출량 산정을 위한 SWAT 모형을 구축한 후, SWAT-CUP을 이용하여 8개 목적함수(R², bR², NS, MNS, KGE, PBIAS, RSR 및 SSQR)를 기준으로 자동 보정을 수행하였다. 최종 매개변수는 목적함수에 따라 서로 다른 범위를 나타내었으며, 모의 결과의 수문특성 또한 상이하게 도출되는 것을 확인하였다. 이것은 각각의 목적함수가 특정 수문특성에 대하여 민감하게 반응하여 서로 다른 모의 성능을 평가하기 때문이다. 즉, 특정 목적함수는 극치값의 잔차에 대해 민감하게 반응하여 첨두값을 잘 모의하는 반면, 저유량 또는 평균유량에 대한 모의 성능이 떨어질 수 있다. 따라서 본 연구에서는 최적 목적함수를 선정하기 위해 8개의 목적함수에 따라 산정된 모의값과 관측값 사이의 수문학적 유사성을 평가하였다. 단순히 유량의 크기 비교 뿐 아니라 유량의 발생 시기, 유역의 반응 및 증가·감소 경향성을 함께 고려하기 위해 수문곡선의 증수부 및 감수부 유지시간 비율을 수문특성으로 정의하여 SWAT 모형을 평가하였으며, 평가 결과를 점수로 정량화하여 나타냈다. 그 결과 최종적으로 SWAT 매개변수 보정을 위한 최적 목적함수는 총점이 높은 MNS (342.48) 및 SSQR (346.45)로 선정되었다.

• 대한기계학회논문집
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• 제17권5호
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• pp.1054-1065
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• 1993

본 연구에서는 정상상태의 단일 주파수에서의 임의의 음압분포로 조화가진되 는 3차원 정방형 밀폐계 음장의 경우에 대한 능동제어를 시도함으로써 사무실과 같은 실내 공간에 대한 능동적 소음저감의 응용 가능성을 검토하고자 하였다. 또한 변환기 의 위치선정을 위하여 상태공간 모드 모델의 모드 근사화에 따른 계수행렬의 요소를 평가함으로써 가제어성과 가광측성을 만족하는 최적한 변환기 (부가음원, 마이크로폰) 의 위치를 선정하였다. 밀폐계 내부의 음압을 저감시키는 목적함수로는 전체 시간평 균 음향 포텐셜에너지를 사용하였으며 폐공간의 음압변동을 이론적으로 규명함으로써 부가적인 음원의 복소세기를 적절히 선정하여 이 음향 포텐셜 에너지의 양을 최소화 시킬 수 있음을 보였다.

• Radiation Oncology Journal
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• 제10권1호
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• pp.49-58
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• 1992

1986년 1월부터 1990년 9월까지 7예의 간외담도계 암 환자를 대상으로 외부 방사선치료와 온열치료를 병행하였다. 7예중 3예는 간외담도암으로 이중 2예는 원발성 담도암 이었고 1예는 위암에서 담도주위로 전이된 암이었다. 7예중 나머지 4예는 담낭암으로 이중 2예는 담낭 절제후 국소적으로 재발된 암이었고 나머지 2예는 원발성 담낭암 이었다. 그리고 7예는 모두 선암으로 확인 되었다. 조사된 방사선의 양은 3000 cGy/2주 조사한 1예를 제외하고 6예에서는 $4500\~5040\;cGY/6\~7$주 조사되었다. 온열치료는 모든 환자에서 방사선치료후 30분 이내에 시행되었으며 방사선치료 기간동안 주 1회 내지 2회씩 총 4회에서 12회까지 시행되었다. 치료효과의 판정은 T-관 T-관 담도촬영술. PTC, 그리고 CT등의 소견으로 하였으며 7예중 6예($86\%$)에서 부분관해를 보였으며 완전관해는 없었다. 7예중 6예는 4개월에서 11개월 애내 사망하였으며 나머지 1예는 현재 11개월째 생존하고 있으나 치료부위 밖에서 국소전이가 관찰되었다. 그리고 7예환자의 정중생존기간은 7개월이었다. 사망환자 6예의 사망원인으로는 원발성 담도암환자 1예에서 폐혈증, 전이성 담도암환자에서 원격 전이, 나머지 4예에서는 원발병소의 진행이 확인되었다. 관찰기간이 짧았으나 모든 환자에서 치료에 잘 적응하였으며 간, 십이지장, 위내의 합병증은 없었고 전이성 담도암 환자에서 일과성 카보닐산혈증이 관찰되었다.

• 한국지리정보학회지
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• 제17권2호
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• pp.59-71
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• 2014

현재 우리나라는 총 인구 감소 속에서도 1인가구는 꾸준히 증가하는 추세를 보이고 있다. 1인 가구의 증가는 사회적, 제도적인 관심사로 부각되고 있으며 이에 따라 1인가구의 증가로 인하여 주택수요의 변화뿐만이 아니라 사회적 약자, 독거노인가구 등 생활 취약계층을 위하여 국가적 차원에서 사회 경제적 대응을 해야 할 필요성이 대두되었다. 이에 본 연구에서는 부산시 1인가구의 분포를 알아보기 위해 센서스 자료를 이용하여 1인가구의 증가지역, 고밀지역, 다수지역 등을 중심으로 접근하였다. 2000년, 2005년, 2010년 각 년도별 시계열적 변화에 따른 공간적 분포에 초점을 두어 주택특성을 고려한 1인가구 밀집지역을 중심으로 대상지를 선정하고 정책적 효율성 차원에서 우선적으로 지원해야 할 밀집지역 선정을 위하여 부산의 6066개의 집계구 데이터를 활용하여 파악하였다. 그 결과 젊은층의 1인가구는 대학가, 오피스시설, 역세권 주변에 많이 분포하고 있었으며 중장년층의 1인가구는 부산의 원도심 지역과 산복도로 상에 많이 분포하고 있는 것으로 나타났다. 이러한 특성들을 종합하여 군집 분석을 실시한 결과 부산의 1인가구 밀집지는 4개의 유형으로 나눌 수 있었다. 이러한 연구는 향후 1인가구의 주택수요 증가 대응방안이나 소형주택공급정책 측면의 업무를 지원하는 기초자료로서의 활용을 기대한다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1247-1247
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• 2001

Constituents of animal biofluids such as milk, blood and urine contain information specifically related to metabolic and health status of the ruminant animals. Some changes in composition of biofluids can be attributed to disease response of the animals. Mastitis is a major problem for the global dairy industry and causes substantial economic losses from decreasing milk production and reducing milk quality. The purpose of this study was to investigate potential of NIRS combined with multivariate analysis for cow's mastitis diagnosis based on NIR spectra of milk, blood and urine. A total of 112 bulk milk, urine and blood samples from 4 Holstein cows were analyzed. The milk samples were collected from morning milking. The urine samples were collected before morning milking and stored at -35$^{\circ}C$ until spectral analysis. The blood samples were collected before morning milking using a catheter inserted into the carotid vein. Heparin was added to blood samples to prevent coagulation. All milk samples were analyzed for somatic cell count (SCC). The SCC content in milk was used as indicator of mastitis and as quantitative parameter for respective urine and blood samples collected at same time. NIR spectra of blood and milk samples were obtained by InfraAlyzer 500 spectrophotometer, using a transflectance mode. NIR spectra of urine samples were obtained by NIR System 6500 spectrophotometer, using 1 mm sample thickness. All samples were divided into calibration set and test set. Class variable was assigned for each sample as follow: healthy (class 1) and mastitic (class 2), based on milk SCC content. SIMCA was implemented to create models of the respective classes based on NIR spectra of milk, blood or urine. For the calibration set of samples, SIMCA models (model for samples from healthy cows and model for samples from mastitic cows), correctly classified from 97.33 to 98.67% of milk samples, from 97.33 to 98.61% of urine samples and from 96.00 to 94.67% of blood samples. From samples in the test set, the percent of correctly classified samples varied from 70.27 to 89.19, depending mainly on spectral data pretreatment. The best results for all data sets were obtained when first derivative spectral data pretreatment was used. The incorrect classified samples were 5 from milk samples,5 and 4 from urine and blood samples, respectively. The analysis of changes in the loading of first PC factor for group of samples from healthy cows and group of samples from mastitic cows showed, that separation between classes was indirect and based on influence of mastitis on the milk, blood and urine components. Results from the present investigation showed that the changes that occur when a cow gets mastitis influence her milk, urine and blood spectra in a specific way. SIMCA allowed extraction of available spectral information from the milk, urine and blood spectra connected with mastitis. The obtained results could be used for development of a new method for mastitis detection.

• Journal of Preventive Medicine and Public Health
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• 제36권1호
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• pp.63-70
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• 2003

Objectives : To investigate the prevalence of cognitive impairment and dementia in elderly people, aged 65 or above, residing in Busan Metropolitan City. Methods : Total of 1,101 old people, aged 65 or above, living in Busan as of December 31, 2001 were selected using stratified three-stage cluster sampling. Cognitive impairment was determined from the MMSE-K score, and dementia confirmed from five psychometric measures and the Barthel index. The crude prevalence, sex-age adjusted for the Korean population, were obtained. Results : With the cut-off point for cognitive impairment was set at 24 points, or below, on the MMSE-K scale, the crude rate of cognitive impairment was 29.3% (15.7% for men and 37.5% for women), and the sex-age adjusted prevalence was 30.5% (17.5% for men and 37.0% for women). When the cut-off point for cognitive impairment was set at 20 points, or below, on the MMSE-K scale, the crude rate of cognitive impairments were 10.0% (4.1% for men and 13.5% for women), and 10.6% (4.7% for men and 13.1% for women), respectively. The crude dementia, and the sex-age adjusted rates were 7.4% (2.4% for men and 10.5% for women), and 8.0% (2.7% for men and 10.0% for women), respectively. Conclusions : The prevalence of dementia in this study was somewhat lower than that reported by other domestic and foreign studies. Our results related to the difference in time and space, diagnostic tools, response rates, and distribution of male and female subjects, etc.

• 한국지하수토양환경학회지:지하수토양환경
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• 제13권5호
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• pp.20-32
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• 2008

제주도의 물관리나 지하수 함양량 산정에 있어서 직접유출량 평가는 유용하게 사용되어 진다. 외도천 유역의 상류지역인 천아계곡과 하류지점에서의 장기 수위관측자료를 이용하여 유출빈도를 분석한 결과, 년간 발생하는 유출 발생빈도는 천아계곡에서는 약 21회, 외도천 하류에서 약 12회였다. 유출지속시간을 고려하면 년간 유출을 관측할 수 있는 기간이 천아계곡에서는 21일, 외도천 하류에서는 12일 정도인 것으로 나타났다. 교차상관분석에 의하여 강우에 대한 수위반응은 약 4시간인 것으로 분석되었으며, 유출이 발생했을 때 천아계곡으로부터 외도천 하류지점까지 수위 전파시간은 약 2시간이었다. 외도천 하류지점에서 유량측정결과, 상시 유출량은 평균 0.39 $m^3$/sec였으며, 기저유출과(직접) 유출량을 평가하기 위해 수위-유량곡선을 개발하였고, 개발된 수위-유량곡선을 이용하여 수위를 시간에 따른 총유출량으로 산정하였다. 수치필터링기법에 의한 총유출량을 기저유출량과 직접유출량으로 분리 낸 결과, 년간 총 하천유량 중 31.8${\sim}$36.5% 정도를 직접유출이 기여하고 있으며 63.5${\sim}$68.2% 정도는 기저 유출이 기여하는 것을 확인하였다.

• 대한물리치료과학회지
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• 제8권2호
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• pp.977-987
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• 2001

The purpose of this study was to examine the effects of sensory integration therapy (SIT) on sensory' motor development and adaptive behavior of cerebral palsy children. The design of this study was quasi experiments with a non-equivalent pre- and post-test control design. Subjects of the study were arbitrarily chosen based on predetermined selection criteria among the cerebral palsy children who were treated as out-patients at two rehabilitation hospitals one in Seoul, and the other in Kyunggi-do. The study was conducted between early April and late July in 2000. Fifteen children were in the experimental group and eleven in the control group. The allocation was done based on ease of experimental treatment. A five-step SIT program was devised from a combination of SIT programs suggested by Ayres(1985) and Finks(1989), and an author-designed SIT program for cerebral palsy children. The experimental group was subjected to 20 to 30 minutes of SIT per session. two sessions a week for ten -week period. The effects of SIT were measured with respect to 9 sub-areas that can be administered to cerebral palsy children out of a total of 17 sub-areas in the Southern California Sensory Integration Test (SCSIT) developed by Ayres (1980). In addition. the scale developed by Russell (1993) for Gross Motor Function Measure (GMFM). and Perception Motor Development Test developed by 中司利一 et al.(1987) were also applied. Adaptive behavior was analyzed using guidelines in two unpublished documents - School-Age Checklist for Occupational Therapy by the Wakefield Occupational Therapy Associates, and the OTA-Watertown Clinical Assessment by the Watertown Occupational Therapy Associates-, and an author-developed Adaptive Behavior Checklist. Collected data were statistically analyzed by SPSS PC for chi square test, Mann-Whitney test, Wilcoxon signed rank test, and paired t-test. The results were as follows: 1. In sensory development, the experimental group exhibited a score increase compared to the control group, but the difference was not statistically significant, Although the experimental group showed improvements in all. 9 sub-areas compared to the control group, only right-left discrimination exhibited statistically significant change. 2. In gross motor development, the experimental group showed improvements in score compared to the control group, but it was not statistically significant. In fine motor development, the experimental group exhibited statistically significant improvements compared to the control group. In sub-area analysis, figure synthesis showed positive change. 3. In adaptive behavior development, post-experimental adaptive behavior scores were higher compared to pre-experimental scores with statistical significance. Furthermore, sub-areas emotional behavior, perception behavior, gross-fine motor function, oral-respiration function, motor behavior, motor planning, and adaptive response exhibited higher scores after SIT. In conclusion SIT was found to be partially effective in sensory and fine motor development, effective in all adaptive behavior areas, and not effective in gross motor development. Thus, this study has shown that SIT is an effective intervention for sensory development, fine motor development, and adaptive behavior for cerebral palsy children. But, for the effectiveness of SIT on gross motor development, further studies employing longer-time experiments are recommended.