휴대폰 카메라용 자동초점 구동기의 충격해석

이성민,김봉석,송준호,이수훈,이혜진,이문구,송준엽,이창우 한국공작기계학회 2008 한국공작기계학회 춘계학술대회논문집 Vol.2008 No.-

Recently, the robustness against daily impact is important according to portablization and downsizing of mobile electronics. Especially, almost parts of cellular phone should undergo drop test when they fall 1.5 m above ground. This test simulates the case when cellular phone slips through user's fingers while he is talking on the phone. This paper studies a drop test of auto focusing (AF) actuator for camera module in cellular phone. This component is composed of voice coil motor (VCM) as an actuator and leaf spring as a guide and suspension. The leaf spring's deformation is essential for the test because its permanent distortion disables the focusing, and then, a high quality photograph cannot be obtained. Up to now the drop test has been carried out after fabricating real AF actuator. We propose a dropt test model which simulates the drop test based on finite element analysis. This model makes us enable investigate the stress acting on the clamping and curved parts of leaf spring. Stress over Von Mises criterion lets the spring deformed permanently, and then AF actuator malfunctioned, It helps us to design and modify AF actuator without manufacturing the real product. And also, it saves the time and cost for the development of new products.

새로운 연노출의 효과지표로서의 혈장 δ-aminolevulinic acid 측정의 유용성

이금원,황보영,김용배,리갑수,이성수,장봉기,함정오,안규동,이병국 순천향대학교 산업의학연구소 2001 순천향산업의학 Vol.7 No.1

To evaluate the usefulness of the measurement of plasma δ - aminolevulinic acid (ALAP) as a new effect indicator of lead exposure, the association of ALAP with blood lead, DMSA chelatable lead and bone lead with a special emphasis of genetic interaction of ALAD polymorphism was studied with 419 lead exposed workers and 85 non-lead exposed workers. Lead workers were recruited from storage battery industries, secondary smelting industries and other lead using industries and non-lead workers selected from electronic refrigerator manufacturing industry. Blood lead, DMSA chelatable lead and bone lead were chosen for parameters of lead exposure. Plasma and urinary ALA were selected for the effect parameter of lead intoxication. Information for age, smoking, drinking habit and body mass index were also obtained. Job duration for lead workers was also collected. The overall prevalence of the variant allele, ALAD type 1-2 or 2-2(ALAD2) in lead exposed workers was 10.0% (42 out of 419 lead workers) which was not differed from control workers (9.4% : 8 out of 85). The means blood lead and DMSA chelatable lead of lead workers with ALAD 1(ALAD type 1-1) were lower than those of lead workers with ALAD2, but the differences were not statistically significant. On the other hand, the mean of tibia lead of lead workers with ALADI was higher than that of lead workers with ALAD2, but the difference was not statistically significant. DMSA chelatable lead showed highest correlation with log transformed plasma ALA(LALAP)(r=0.682) and blood lead and tibia lead had r=0.650, r=0,402 correlation coefficient with LALAP respectively On the other hand. log transformed urinary ALA(LALAU) had lower correlation coefficient with all three parameters of lead exposure than LALAP. The equation of robustic simple linear regression of blood lead on LALAP was LALAP=2.0439+0.0165PbB in ALADI lead workers and LALAP=2.031+0.0121PbB in ALAD2 lead workers. ALAD genotype in the multiple regression analysis of blood lead with LALAP after adjusting for possible confounders(sex, ago, BMI, smoking and drinking status and job duration) showed significant main effect on LALAP resulting lower LALAP in ALAD2 lead workers than ALADI lead workers. On the other hand, effect modification of ALAD genotype was observed in the multiple regression analysis of tibia lead with LALAP after adjusting for possible confounders, but there was no significant effect of ALAD genotype in the multiple regression analysis of DMSA chelatable lead with LALAP after covariate adjustment. With above results, plasma ALA was found to be a useful effect parameter of lead exposure compared with urinary ALA. It was also observed that ALAD polymorphism made significant effect on the association of blood and tibia lead with ALAP. Thc lower plasma ALA in ALAD2 lead workers suggested supportive effect of ALAD2 in lead exposure.

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.

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

당밀의 첨가가 갈근탕박 사일리지의 품질과 산양의 기호성에 미치는 영향

김성복,문계봉,이봉덕,오홍록,배형철,이수기 충남대학교 농업과학연구소 2006 농업과학연구 Vol.33 No.1

Two experiments were conducted to investigate the effects of molasses supplementation to silage materials in ensiling Galgeuntang (herbal medicine) meal on the quality of silage, and its palatability in Korean native goats. In experiment Ⅰ, molasses was added at the levels of 0, 0.5, and 1.0% to Galgeuntang meal with three replicates per treatment. In experiment Ⅱ, three 1.5-yr-old Korean native goats were used to measure palatability. In experiment Ⅰ, lactic acid contents in molasses treatments were significantly(p<0.05) higher, and pH and butyric acid contents were lower than those of non-molasses treatment. In addition, molasses treatment increased total microbial cell counts in MRS medium for lactobacillus, but decreased total microbial cell counts in PDA medium for fungi. Molasses supplementation to silage materials increased in vitro dry matter disappearance. Molasses supplementation tended to increase silage intake in Korean native goat (experiment Ⅱ), but the difference was not significant(p>0.05). It is concluded that molasses supplementation to silage materials in ensiling herbal medicine meal could improve its preservability and palatability, the higher the better.

연작업자들의 신기능 평가에서 요중 δ-aminolevulinic acid 측정의 의의

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

To clarify the effect of occupational lead exposure on renal function 241 lead workers working and 56 non lead workers were studied in 5 lead acid battery industries. Study variables for renal effect were urinary N-acetyl-β-D-glucosaminidase(NAG), urinary total protein(U-TP), blood urea nitrogen(BUN), serum creatinine(S-Cr), and serum uric acid(S-Ua). On the other hand, blood lead(PbB), zinc protoporphyrin in whole blood(ZPP), and delta-aminolevulinic acid in urine(δ-ALA) were selected for the variables of lead exposure. Information on age, work duration, smoking and drinking history were also obtained. The results obtained were as follows. While the mean values of lead exposure indicators of lead workers were significantly different from non-exposed ones, the mean values of BUN, U-TP and S-Cr of renal function indicators of exposed were also different from non-exposed. BUN, U-TP and NAG showed statistically significant correlation with PbB and ZPP, and NAG revealed also statistically strongly significant correlation with δ-ALA. On multiple regression using renal fuction indicators as a dependent variable and δ-ALA, age, work duration,lead exposure,smoking and drinking as independent variables, only δ-ALA contributed to NAG.

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.

직업적 연폭로가 일부 신경행동학적 검사수행에 미치는 영향

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

In order to investigate that blood lead levels of lead exposed workers is associated with decreased performance in neurobehavioral tests in adults, we investigate 78 workers in a battery industry. Three items among neurobehavioral core test battery of World Health Organization, including digit span, Santa ana dexterity, digit symbol were administered to workers occupationally lead exposed workers by operational guide for the WHO neurobehavioral core test battery. Blood lead (PbB) and zinc protoporphyrin in whole blood (ZZP) were selected as an index of lead exposure. Detailed occupational history such as exposed agent, age, work duration, smoking and drinking habits, were recorded as confounding factors. After controlling age, the results of digit span and digit symbol among the neurobehavioral tests were significant contributed by PbB.

연작업자들에서의 δ -aminolevulinic acid dehydratase 유전형질의 다형성이 신기능에 미치는 영향

안익수,황보영,김용배,리갑수,이성수,장봉기,함정오,안규동,이병국 순천향대학교 산업의학연구소 2001 순천향산업의학 Vol.7 No.1

δ-aminolevulinic acid hehydratase (ALAD) is a polymorphic enzyme that has two alleles, ALAD1 (ALAD1-1 as phenotype) and ALAD2 (ALAD1-2 or ALAD2-2 as phenotype). ALAD genotype has been reported to modify the toxicokinetics of lead. To investigate the influence of ALAD genotype polymorphism on renal function in lead workers, author studied 1022 male lead workers and 149 non lead workers in the same industries. For the cross-sectional renal function indices, blood urea nitrogen (BUN), serum creatinine, uric acid and total protein were selected. Blood lead and blood zinc protoporphyrin were also measured as indices of lead exposure. Information on weight, age, job duration, smoking & drinking history were collected. Following results are as follows: 1. Whereas the mean (standard deviation) of blood lead and blood ZPP of lead workers were 27.2±12.5 ㎍/㎗ and 57.7±37.8 ㎍/㎗, those of non-lead workers in the same premises were 14.9±6.5 ㎍/㎗ and 44.6± 15.8 ㎍/㎗ respectively. The difference of mean blood lead and blood ZPP between two groups were statistically significant. 2. Whereas the prevalence of the variant allele, ALAD2 in 1022 lead workers was 10.2 %, the prevalence of that in 149 non-lead workers was 7.4 %. But there was no difference of prevalence between two groups. 3. The mean±standard deviation of blood lead of subjects with ALAD1 was 25.5± 12.7 ㎍/㎗ and was slightly lower than that of subjects with ALAD2 (26.5±10.9 ㎍/㎗), and the mean±standard deviation of blood ZPP of subjects with ALAD1 was slightly higher than that of subjects with ALAD2 (56.7±37.3 ㎍/㎗ vs 48.9±18.6 ㎍/㎗). But the differences of blood lead and blood ZPP between two genotypes were not statistically significant. 4. There were no differences of cross-sectional renal function indices (BUN, serum creatinine, uric acid and total protein) either by lead workers and non-lead workers or two genotypes. 5. In multiple regression analysis of ALAD genotype on BUN after controlling for possible confounders (sex, weight, job duration, smoking and drinking status), the mean of BUN in ALAD2 subjects was 0.629 ㎎/㎗ lower than ALAD1 subjects with a weak statistical significance (p=0.07). But in logistic analysis of ALAD genotype on median value of BUN revcaled that subjects of ALAD2 genotype were 32% less likely to have median value or more of BUN than subjects of ALAD1 with odd ratio of 0.618 (95% confidence interval 0.411-0.920). 6. In multiple regression analysis of ALAD genotype on serum creatinine after controlling for possible confounders (sex, weight, job duration, smoking and drinking status), the mean of serum creatinine in ALAD2 subjects was 0.0271 ㎎/㎗ lower than ALAD1 subjects with statistical significance (p=0.02). On the other hand, in logistic analysis of ALAD genotype on median value of serum creatinine revealed that subjects of ALAD2 genotype were 30% less likely to have median value or more of scrum creatinine than subjects of ALAD1 with odd ratio of 0.700 (95% confidence interval 0.442-1.080). With the above results, it was found that the variant allcle, ALAD2 appeared to modify the association of lead and renal function and ALAD2 genotype may be supportive for the protective effect of lead.

매크로/마이크로 레벨 볼트 결합 구조물에서의 실험적/해석적 방법을 통한 시스템 특성 비교

김봉석,이성민,이문구,이수훈,Jun Ni,송준엽,이창우,하태호 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

As the micro technology and miniaturization of a structure and component in the last couple of decades have been concretely realized, the understanding of structural and dynamic characteristics and prediction of dynamic behavior are indispensable to the miniaturized structures and micro machines. This paper shows the effect of dynamic characteristics in bolt-jointed structures by comparing natural frequencies and mode shapes between macro and micro-scale beams through experimental modal analysis and finite element analysis with a1 8 test models by materials, by size, and by joining condition; that is, SS41 and A16061-T651, micro and macro, and monolithic beam and bolt-jointed beam.