DCT를 이용한 영상의 윤곽선 추출을 위한 양자화 테이블 비교분석

최현주,성병우,최흥국,서재현 인제대학교기초과학연구소 1998 자연과학 Vol.2 No.-

본 논문에서는 DCT(discrete consine transform)를 이용하여 영상 데이터를 공간 영역에서 주파수 영역으로 변환하여 주파수 영역별로 분해한 뒤, 윤곽선 추출과 압축을 동시에 하기 위한 여러 양자화 테이블을 적용하고, IDCT(Inverse DCT)를 이용하여 복원한 결과를 비교 분석함으로써, 보다 정확한 윤곽선을 가진 영상을 추출할 수 있는 양자화 테이블을 구했다. 이 양자화 테이블을 DCT 처리된 영상에 적용했을 때 윤곽선과 압축 효과를 가진 영상을 얻을 수 있었다. In this paper, we transform image data from spatial domain to frequency domain using DCT, decompose it into each frequency band. We apply various quantization table for edge detection and compression simultaneously. We researched a quantization table for extracting image with exact edge, as compare and analyze restored images using IDCT. When we applied this quantization table to the DCT transformed image, acquired the image with edge and compression effect.

업종에 따른 연 취급 사업장의 기중 연 농도 및 연 노출 수준 평가

이병국,김용배,리갑수,안현철,김화성,이용진,황규윤,장봉기,이성수,안규동 순천향대학교 산업의학연구소 1999 순천향산업의학 Vol.5 No.1

In order to obtain an useful information for health management and biological monitoring of lead exposed workers, Authors tried to investigate air lead level and the lead exposed level of workers in lead industry according to occupational category. The subjects in our study were 2074 workers in 7 lead-using industries, and study subjects were divided into 4 occupational categories such as storage battery industry (type 1), primary smelting industry (type 2), secondary smelting industry (type 3) and litharge making industry (type 4). Blood zincprotoporphyrin concentration (ZPP), blood lead concentration (PbB) and urinary δ -aminolevulinic acid (ALAU), hemoglobin (Hb), hematocrit (Hct) were selected as the indices of lead exposure. Personal variables such as age, work duration were also collected. The results were as follows. 1. The geometric mean air lead in 9 lead-using industry was 0.1133±4.3120 ㎎/㎥, and that in type 1, 2, 3 and 4 was 0.1038±3.4952 ㎎/㎥, 0.0429±3.4329 ㎎/㎥, 0.1877±2.5123 ㎎/㎥ and 0.9961±5.2910 ㎎/㎥, respectively. 2. The mean ZPP in 9 lead-using industry was 53.1±28.0 ㎍/㎗, and that in type 1, 2, 3 and 4 was 52.0±24.8 ㎍/㎗, 48.0±16.4 ㎍/㎗, 109.8±85.6 ㎍/㎗ and 74.3±37.8 ㎍/㎗, respectively. There was significant difference in ZPP according to occupational category (P<0.01). The percents of lead workers whose ZPP were above 100 ㎍/㎗ in type 1, 2, 3 and 4 were 4.0%, 1.7%, 34.3% and 21.6%, respectively. 3. The mean PbB in lead-using industry was 26.0±11.2 ㎍/㎗, and that in type 1, 2, 3 and 4 was 25.3±11.1 ㎍/㎗, 26.7±8.8 ㎍/㎗, 50.3±15.2 ㎍/㎗ and 36.4±11.0 ㎍/㎗, respectively. There was significant difference in PbB according to occupational category (P<0.01). The percents of lead workers whose PbB were above 40 ㎍/㎗ in type 1, 2, 3 and 4 were 10.4%, 7.7% 71.9% and 43.2%, respectively. 4. While the correlation of Hb corrected PbB with ZPP was higher than non corrected PbB, the correlation of log-transformed ZPP with PbB was higher than non corrected ZPP. 5. Simple linear regressions of PbB and corrected PbB as independent variable with ZPP, log-transformed ZPP and ALAU as dependent variable were statistically significant (P0.01). Coefficient of determination of corrected PbB with other variables was higher than non corrected PbB. As the result of this study, it was suggested that reconsideration of environmental and biological monitoring program was highly recommended for secondary smelting and litharge making industry.

후외상성 진주종 2례

남부현,김병국,고필준,심장한,박찬일 충남대학교 의과대학 지역사회의학연구소 1996 충남의대잡지 Vol.23 No.1

Post-traumatic cholesteatoma can be originated in the middle ear or mastoid cavity after head trauma such as temporal bone fracture, penetrating injury of the temporal bone or blast injury of the tympanic membrane. It usually takes a long time to develope cholesteatoma after injury, and physicians may overlook its association with previous, trauma. Post-traumatic cholesteatoma can be suspected in patients with head trauma history and atypical cholesteatoma findings. We experienced two cases of cholesteatoma which found behind the intact tympanic membrane in 7 and 13 years old boys with history of head trauma, and we are reporting this with a discussion and literatural review.

보건관리 대행사업 이후 작업환경 수준의 변화

박복현,김화성,이용진,안규동,이병국 순천향대학교 산업의학연구소 1999 순천향산업의학 Vol.5 No.1

This study was performed to evaluate the threshold limit values(TLVs) exceeding rates and periodical changes based on the results from work environmental measurement for 40 factories applied health service program, located in Cheonnan area, from 1995 to 1997. The obtained results were as follows; 1. The hazaed frequency in environmental monitoring were noise(865, 34.4%), illumination(804, 31.9%), dust(205, 8.1%), organic solvent(371, 14.7%), lead(114, 4.5%), and specific chemicals(31, 1.2%), heavy metal(127, 5.0%) in order. 2. The order of TLVs exceeding rate of hazardous agents by type of industries were cement-related manufacture(42.3%), fiber industry(40.0%), food stuff industry(24.3%), metal work industry(21.8%), electronics manufacture (9.9%), other industries(10.2%), chemical industry(7.9%). 3. The mean exceeding rates of hazard by type of industry were 29.5% in noise, 27.3% in dust, 25.8% in specific chemicals, 10.2% in solvent and 7.9% in lead, but none in heavy metal. 4. The average of standardized values of noise divided by TLV were decreased in food stuff industries and chemical industries, but not changed in fiber and cement-related industries. While, the average of standardized values of organic solvents divided by TLVs were decreased in electronic manufacturing industries and other industries.

납 폭로 근로자에서 δ-aminolevulinic acid dehydratase 유전형질이 zinc protoporphyrin 및 δ-aminolevulinic acid에 미치는 영향

이병국,황규윤,장봉기,김용배,리갑수,안현철,김화성,이성수,안규동,박종범 순천향대학교 산업의학연구소 1999 순천향산업의학 Vol.5 No.1

The inhibition of δ-aminolevulinic acid dehydratase (ALAD) in the heme synthetic pathway results in increased protophoryphyrin (ZPP) and δ-aminolevulinic acid (ALA) and is responsible for some of toxicological effects of lead. This enzyme is coded by the ALAD gene containing 2 co-dominant alleles. The polymorphisms of ALAD gene may be related to differential effects of lead on ZPP and ALA, ALAD genotype was measured in 975 Korean male lead workers, of whom 897 were homozygous for ALAD1 (ALAD 1-1 genotype) and 96 were heterozygous for ALAD2 (ALAD 1-2 genotype). Blood lead in subjects with ALAD1 was significantly higher than those with ALAD2 (p = 0.01). No difference between ALAD genotypes was found for age, exposure duration, ZPP, ALA, hemoglobin, hematocrit, body mass index, tobacco and alcohol use. After adjustment for possible confounders, ALA and ZPP became significantly elevated in ALAD1 subjects (p = 0.004 and 0.055, respectively). This result suggests that ALAD1 subjects may be more susceptible to the hematotoxicologic effects of lead than ALAD2 subjects.

AMPS 시스템과 주파수를 공유하는 CDMA시스템의 링크 해석

문병현,손병국,최정희 대구대학교 과학기술연구소 1999 科學技術硏究 Vol.5 No.5

In this paper, the forward and reverse link cellular capacities analysis of code division multiple access (CDMA) is performed when the systems are sharing the same frequency band. It is assumed that the frequency reuse pattern K=5 is used for the analysis. Formule that describe the relationship between the number of CDMA and AMPS users for a given carrier to interference ratio (GI) of each are presented. In the comparison of the forward and reverse link analysis, forward link is smaller than reverse link. Therefore, the system capacity depends on the forward link rather than the reverse link.

글쓰기 교육과 한문 교육의 앞으로의 방향

손병국,오정란,조규일,최기용,한지현 광운대학교 인문사회과학연구소 2000 인문사회과학논문집 Vol.29 No.-

연취급 근로자들의 사회 심리적 스트레스와 연노출 지표들간의 관련성

김용배,안현철,황보영,리갑수,황규윤,이성수,안규동,이병국 大韓産業醫學會 2000 대한직업환경의학회지 Vol.12 No.1

목 적 : 연취급 근로자를 대상으로 사회 심리적 스트레스 수준을 알아보고 이를 기초자료로 활용하며 사회 심리적 스트레스와 연노출 지표들간의 관련성을 알아보고자 시도하였다. 방 법 ' 1차 연제련업종의 근로자 234명을 대상으로 일반적 특성, 사회 심리적 스트레스, 직업적 특성과 사회적 지지를 문진과 설문지를 통해 확인했으며 연노출 수준을 알기 위해 혈중 ZPP 농도, 혈중연농도, 요중 δ-ALA 배설량, 혈색소, 혈구용적치등을 측정했다. 결 과 : 단일변량 분석결과 혈중 연농도 수준과 직업적 특성에 따른 사회 심리적 스트레스는 유의한 차이가 있었으며 혈중 연농도가 증가함에 따라 스트레스 수준도 증가되는 경향을 나타냈다. 사회 심리적 스트레스와 연노출 지표 및 다른 변수들간의 관련성을 파악하기 위하여 상관분석을 실시한 결과 혈중 연농도만이 사회 심리적 스트레스와 양의 상관관계를 나타냈으며 유의했다. 결 론 : 고농도 연노출의 가능성이 있는 직종인 경우 기존의 연관련 자각증상에 대한 설문조사와 함께 사회 심리적 스트레스 측정도 병행하여 실시하는 것이 연에 의한 건강장해를 조기에 발견하고 예방하는데 필요하다. Objectives : This study was carried out to assess psychosocial distress of lead workers and to examine the relationship between lead exposure indices and psychosocial distress. Methods The study design was cross-sectional and research subjects were 234 lead workers in primary smelting industry. General characteristics, job characteristics and social support were obtained by self-administered questionnaire and history taking. Psychosocial distress was measured using PWI(Psychosocial Well-being Index), a 45-item self-administered instrument. Blood lead(PbB), zinc protoporphyrin(ZPP), δ-aminolevulinic acid in urine (ALAU) were selected as indicators of lead exposure. Results : There was significant difference in PWI according to lead exposure level and job characteristics. The results of correlation analysis showed that PWI was significantly correlated with PbB (r=0.203, p=0.002). Conclusions : Our results supported the association between lead exposure and psy-chosocial distress. The inclusion of psychosoclal distress measurement as a special health examination for lead workers was highly recommended for the effective health manage-ment.

직업적 연폭로에서 혈중 연량 수준에 따른 선별검사로서의 혈중 ZPP 검사의 타당도

한구석,안현철,김용배,리갑수,김화성,황규윤,장봉기,이성수,안규동,이병국 순천향대학교 산업의학연구소 1999 순천향산업의학 Vol.5 No.1

In order to evaluate the validity of current screening criteria of lead exposure and to provide effective information for the better health management of lead workers, author investigated the interrelationship between blood lead and blood zinc protoporphyrin(ZPP) and evaluate the validity of blood zinc protoporphyrin as the screening test and blood lead as gold standard of diagnostic test. The total of 2245 lead workers (male workers: 1982, female workers : 263) from 12 lead using industries were studied. Blood lead, ZPP, hemoglobin and hematocrit were selected as lead exposure variables. Personal information on sex, age and work duration were also checked. Blood lead was measured with flameless atomic absorption spectrometry (model: Hitachi 8100) using standard addition method. Blood ZPP was measured with portable hematoflurometer (model: Aviv 206). The results obtained were as follows: 1. The mean blood lead of all lead workers were 0.7±14.3㎍/㎗(Male: 31.0±14.4㎍/㎗, Female: 28.2±12.9㎍/㎗), whereas the mean blood ZPP of those were 68.1±47.5㎍/㎗(Male: 63.9±43.7㎍/㎗, Female: 100.1±61.0㎍/㎗). The mean value of hemoglobin and hematocrit of all lead workers were 14.5±1.5g/㎗(Male: 14.7±1.3g/㎗, Female: 12.3±1.2g/㎗) and 45.4±3.6(Male: 46.2±2.8, Female: 39.5±3.1) respectively. 2. Validity of test using blood zinc protoporphyrin as screening test for blood lead levels of 30㎍/㎗ as gold standard of diagnostic test revealed that the highest validity value for male and female lead workers were 50 and 90 ㎍/㎗ of ZPP respectively, showing 50 and 60 ㎍/㎗ of ZPP for all lead workers. While those test for blood lead levels of 40㎍/㎗ as gold standard of diagnostic test revealed that the highest validity value for male and female lead workers were 60 and 90 ㎍/㎗ of ZPP respectively, showing 60 ㎍/㎗ of ZPP for all lead workers, those test for blood lead levels of 50 and 60㎍/㎗ as gold standard of diagnostic test revealed that the highest validity value for male and female lead workers were 60 or 70 and 100 ㎍/㎗ ZPP respectively, showing 60and 70 or 80 ㎍/㎗ of ZPP for all lead workers. 3. Predictive value of test using blood zinc protoporphyrin as the screening test for different blood lead levels of 30, 40, 50 and 60㎍/㎗ as gold standard of diagnostic test revealed that positive predictive value of screening test were decreased by the increase of blood lead level regardless of csreening criteria value ZPP and negative predictive value of screening test were increased accordingly regardless of screening criteria value of ZPP. On the other hand, within same blood lead level as a gold standard positive predictive values were inceased by the increase of screening criteria value of ZPP, whereas the negative predictive value were decreased accordingly by the the increase of screening criteria value of ZPP. 4. The correlation analysis of all lead workers among study variables revealed that CPbB and natural log transformation ZPP(LZPP) were better correlated with other variables and found to be better estimate than PbB and ZPP themselves. The age was correlated with all other variables, but the work duration was not. The correlation analysis of male and female workers among study variables revealed the same results with all lead workers. 5. The slope of simple linear regression of CPbB (independent variable) with ZPP in female workers(3.223)was steeper than in male workers(2.144). That of lead workers with work duration of less than 1 year was steeper than that of lead workers whose work duration was more than 1 year. But there was no slope difference between two groups divided by their work duration of 2 years less and more. The slope of simple linear regression of CPbB lead (independent variable)with ZPP in lead workers whose blood lead were higher than 30㎍/㎗and 40㎍/㎗ were steeper than those whose blood lead were less than 30㎍/㎗ and 40㎍/㎗. 6. The slope of simple linear regression of CPbB (independent variable) with ZPP in lead industries with low mean blood lead were less steeper than those with high mean blood lead. 7. The slope of simple linear regression of CPbB (independent variable) with LZPP in female workers(0.0308was steeper than in male workers(0.0253). That of lead workers with work duration of less than 1 year was steeper than that of lead workers whose work duration was more than 1 year. But where was no slope difference between two groups divided by their work duration of 2 years less and more. While the slope of simple linear regression of CPbB lead (independent variable) with LZPP in lead workers whose blood lead were hogher than 30㎍/㎗ was not steeper than those whose blood lead were less than 30㎍/㎗, there was no slope difference between two groups whose blood lead were less than 40㎍/㎗ and more than 40㎍/㎗. 8. The slope of simple linear regression of CPbB (independent variable) with LZPP in lead industries with low mean blood lead were less steeper than those with high mean blood lead, but the difference was not significant then that of CPbB and ZPP. With above results, it is recommended that the screening criteria value of ZPP should be down to 60-70㎍/㎗ from 100㎍/㎗ for male lead workers and screening criteria of ZPP for female lead workers was all right with current value of 100㎍/㎗. So it is recommended to make different screening criteria of ZPP for male and female workers like the hemoglobin and hematocrit screening criteria. It is also preferable to use CPbB and LZPP rather than uncorrected PbB and ZPP in the evaluation of lead exposure for lead workers.

연폭로 근로자들의 연폭로 수준에 따른 혈압변화에 관한 연구

리갑수,안현철,김용배,이성수,안규동,이병국 순천향대학교 산업의학연구소 1997 순천향산업의학 Vol.3 No.1

To evaluate the blood pressure change of lead workers by lead exposure level, authors analyzed 1,009 lead workers. Study variables were systolic and diastolic blood pressure, smoking and drinking habit, age, work duration, blood lead concentration(PbB), ZPP, hemoglobin, BMI and cholesterol. The results were obtained as follow; 1. Means of systolic and diastolic blood pressure were 126.93mmHg and 74.08mmHg. Systolic pressures were significantly higher in males and drinkers than in females and non-drinkers. Blood pressure was increased as age and work duration were increased. 2. Means of PbB and ZPP were 26.79㎍/㎗, 61.38㎍/㎗ respectively. Male workers' PbB was higher than female workers', and ZPP was contrary. PbB and ZPP were increased as age and work duration were increased. Smokers' and drinkers' PbB were not different from nonsmokers' and nondrinkers' but ZPP were lower. 3. As PbB was increased, systolic pressure was increased, but diastolic pressure was not increased. 4. There were no significant increase in both systolic and diastolic pressure by increase of ZPP. 5. In pearson's correlation analysis, systolic pressure was correlate with BMI(R^(2)=0.2618), hemoglobin (R^(2)=0.1794), cholesterol(R^(2)=0.14334), PbB(R^(2)=0.12616) and alcohol consumption per week(R^(2)=0.10925). 6. In pearson's correlation analysis, diastolic pressure was correlate with BMI(r-square : 0.25037), age, hemoglobin, cholesterol and work duration, but not correlate with PbB. 7. Forward multiple regression analysis using systolic pressure as dependent variable revealed that BMI, PbB hemoglobin and cholesterol in order were significantly contributed to dependent variable. 8. Forward multiple regression analysis using diastolic pressure as dependent variable revealed that BMI, age, hemoglobin, smoking and cholesterol in order were significantly contributed to dependent variable.