• 제목/요약/키워드: Level D

검색결과 11,096건 처리시간 0.039초

소음노출량측정기의 Set Up 방법간의 시간가중평균값(TWA)의 차이 (Difference of Time Weighted Averages in Different Setting Ups for Noise Dosimeter)

  • 양흥석;이광묵;원정일
    • 한국산업보건학회지
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    • 제5권2호
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    • pp.193-199
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    • 1995
  • This study was designed to investigate the difference of time weighted average(TWA) of noise levels and noise doses by the different operating parameter settings such as exchange rate, threshold level and criterion level for noise dosimeter in the field measurements of noise at industrial working environments. The time weighted averages of noise level and noise doses for noise working environments were determined by noise dosimeter on 80 workers employed at 20 industrial establishments of 8 industries. The results obtained were as follows: 1. The mean time weighted average(TWA) of the noise working environments by the operating parameter settings showed 93.4 dB(A) in 3 dB of exchange rate, 80 dB of threshold level and 90dB of criterion level 92.0 dB(A) in 3 dB-exchange rate, 90 dB-threshold level and 90 dB-criterion level, in 90.8 dB(A) in 5 dB of exchange rate, 80 dB of threshold level and 90 dB of criterion level, and 86.7 dB(A) in 5 dB of exchange rate, 90 dB of threshold level and 90dB of criterion level. 2. ln group of noise level less than 90 dB(A), mean TWAs of 80 dB of threshold level were significantly higher than that of 90 dB of threshold level in 3 dB and 5 dB of exchange rate. 3. The case exceeded threshold limit value of noise was 49(61.3 %) in 3dB, 80dB and 90 dB setting, 44(55.0 %) in 3 dB, 90 dB, 90 dB setting, 33(41.3 %) in 5 dB, 80dB, 90 dB setting and 26(32.5%) in 5 dB, 90 dB, 90 dB setting. Above considerations in mind, it is suggested that exchange rate and threshold level be specified in related laws and regulations in the evaluation of working environments noise.

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정상 성인의 혈청 Vitamin D 수준과 이에 영향을 주는 변인에 관한 연구 (A Study on Vitamin D Status and Factors Affecting It in Young Adults)

  • 문수재
    • Journal of Nutrition and Health
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    • 제29권7호
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    • pp.747-757
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    • 1996
  • In this study, the serum level of 25-hydroxyvitamin D(25-(OH)D) was measured by high pressure liquid chromatography(HPLC), and factors affecting it were investigated in 72 young adults age ranging from 21 years to 39 years with normal bone density. The mean level of serum 25-(OH)D was 20.0$\pm$6.8ng/ml in males and 26.1$\pm$12.3ng/ml in females, which was significantly higher in females (p<0.01). The serum level of parathyroid hormone(PTH) showed a negative correlation with that of 25-(OH)D(p<0.05). Time spent outdoors in a day correlated positively with the serum level of 25-(OH)D(p<0.01). During the day, a specific time between 12:00 a.m. and 2:00 p.m. showed the most significant correlation with the level of 25-(OH)D(p<0.005). Among the nutrients studied, fat and vitamin D intake were positively correlated with the serum 25-(OH)D level. Stepwise multiple regression analysis showed that the serum level of 25-(OH)D could be fit by vitamin D intake(34.7% explained), serum PTH level (27.3% explained) and the time spent outdoors during the specific time(28.4% explained).1996)

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한강상 교량의 소음.진동레벨 조사.연구 (A survey and research of a noise & a vibration level of bridges on the Han river)

  • 서광석;이연수;박영만;이상수;전재식
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 추계학술대회논문집
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    • pp.278-280
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    • 2007
  • This survey was carried out to provide a sound and a vibration level of bridges on the Han river. A sound and a vibration level of 6 bridges(Ban po, Cheon ho, Olympic, Jam soo, Young dong, Dong ho) were measured. The X-axis vibration level($L_{10}$) was $42{\sim}60$ dB(H), Y-axis vibration level was $41{\sim}52$ dB(H) and Z-axis vibration level was $44{\sim}77$ dB(V). The Z-axis vibration level($L_{10}$) on the midpoint of bridges was 68 dB(V), and on the joint point was 56 dB(V). The sound level was $77{\sim}84$ dB(A). The sound level of Jam soo bridge was higher than any other bridges.

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폐경전 성인직장여성의 혈청 25-Hydroxyvitamin D상태 및 관련인자에 관한 연구 (Serum 25-Hydroxyvitamin D Status and Associated Factors in Premenopausal Working Women)

  • 임화재
    • 대한지역사회영양학회지
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    • 제10권1호
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    • pp.79-90
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    • 2005
  • This study was performed to estimate serum 25-hydroxyvitamin D level and to evaluate the relationship between serum 2S-hydroxyvitamin D level and associated factors. The subjects were 61 premenopausal working women aged 30 - 49 y in Busan. The serum 25-hydroxyvitamin D level was measured by radioimmunoassay. Data for physiological characteristics, lifestyle factors, physical activity and nutrient intake were assessed by questionnaire including information about outdoor activity time, daily activity diary and 24 hr recall method. The mean vitamin D intake was 3.12 ug, which corresponded to $62.5\%$ of the Korean RDA. The mean level of serum 25-hydroxyvitamin D was 31.0 ng/mL. Low 25-hydroxyvitamin D (<25 nmol/L) was not found in the subjects. The serum 2S-hydroxyvitamin D level showed positive significant correlations with exercise hours, daily energy expenditure, hours of outdoor activity per weekdays (p < 0.001, P < 0.05, P < 0.05). Exercise hours were found to be the most important determinant of serum 25-hydroxyvitamin D level. Therefore nutritional education for increasing hours of physical activity including indoor and outdoor exercise, is needed for premenopausal working women to increase vitamin D status.

실습선 부산 403호의 진동과 소음 (Vibration and Noise Level on the Training Ship Pusan 403)

  • 박중희
    • 수산해양기술연구
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    • 제23권2호
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    • pp.8-8
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    • 1987
  • 1986년 8월 1일부터 8월 30일까지 완도, 목포, 흑산도 항로와 흑산도에서 제주항 항로상에서 해상이 잔잔한 날을 택하여 실습선 부산403호의 순항시와 표박시의 주기관과 각 갑판의 선수미선상에서의 주요장소에서의 진동과 소음준위를 측정하고 진동분석을 통하여 진동변위, 속도, 가속도를 비교·고찰한 결과를 요약하면 다음과 같다. 1. 진동과 소음압준위. 1) 주갑판상에서 진동과 소음준위가 가장 높은 곳은 주기관의 수직상면이고 가장 낮은 곳은 소음은 선교수직하, 진동은 선수부창고의 수직하면에서이다. 2) 주기관 cylinder head, 기관실 좌측, 축계관상부에서 순항시의 진동준위는 80, 67, 65dB이고, 소음준위는 각각 104, 87, 86dB이다. 3) 선교를 통과하는 수직선상의 진동준위는 최저갑판에서 60dB로 가장 높고, 선교갑판에서 55dB로 가장 낮으며, 소음준위는 compass deck에서 75dB로 가장 높고, 최저갑판에서 53dB로 가장 낮다. 4) 노천갑판에서 진동과 소음준위는 모두 보우트갑판에서 각각 65, 84dB로 가장 높고, 진동준위는 교실 위에서 51dB, 소음준위는 선수누갑판에서 57dB로 가장 낮다. 5)최저갑판의 진동과 소음준위는 모두 기관실에서 가장 높아 각각 65dB, 85dB이고, 선수부창고에서 가장 낮아 각각 54dB, 52dB이다. 진동준위와 소음준위를 비교하면 기관실을 중심으로 하여 선수쪽에서 진동준위가 높고, 선미쪽에서는 소음준위가 높다. 2. 진동분석 1) 진동변위는 주기관 cylinder head에서 100μm로 가장 크고, compass deck에서는 3μm로 가장 작다. 또 진동속도는 주기관 cylinder head에서 11mm/sec로 가장 빠르고, compass deck에서 0.07mm/sec로 가장 느리며, 이들은 모두 100Hz 이상에서는 급격한 감쇄를 보였다. 2) 진동가속도는 주기관 cylinder head에서 중심주파수 1KHz, 1.1mm/sec 상(2) 로 가장 빠르고 compass deck에서 30Hz, 0.05mm/sec 상(2) 로 가장 느리다.

실습선 부산 403호의 진동과 소음 (Vibration and Noise Level on the Training Ship Pusan 403)

  • 박중희
    • 수산해양기술연구
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    • 제23권2호
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    • pp.54-60
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    • 1987
  • 1986년 8월 1일부터 8월 30일까지 완도, 목포, 흑산도 항로와 흑산도에서 제주항 항로상에서 해상이 잔잔한 날을 택하여 실습선 부산403호의 순항시와 표박시의 주기관과 각 갑판의 선수미선상에서의 주요장소에서의 진동과 소음준위를 측정하고 진동분석을 통하여 진동변위, 속도, 가속도를 비교.고찰한 결과를 요약하면 다음과 같다. 1. 진동과 소음압준위. 1) 주갑판상에서 진동과 소음준위가 가장 높은 곳은 주기관의 수직상면이고 가장 낮은 곳은 소음은 선교수직하, 진동은 선수부창고의 수직하면에서이다. 2) 주기관 cylinder head, 기관실 좌측, 축계관상부에서 순항시의 진동준위는 80, 67, 65dB이고, 소음준위는 각각 104, 87, 86dB이다. 3) 선교를 통과하는 수직선상의 진동준위는 최저갑판에서 60dB로 가장 높고, 선교갑판에서 55dB로 가장 낮으며, 소음준위는 compass deck에서 75dB로 가장 높고, 최저갑판에서 53dB로 가장 낮다. 4) 노천갑판에서 진동과 소음준위는 모두 보우트갑판에서 각각 65, 84dB로 가장 높고, 진동준위는 교실 위에서 51dB, 소음준위는 선수누갑판에서 57dB로 가장 낮다. 5)최저갑판의 진동과 소음준위는 모두 기관실에서 가장 높아 각각 65dB, 85dB이고, 선수부창고에서 가장 낮아 각각 54dB, 52dB이다. 진동준위와 소음준위를 비교하면 기관실을 중심으로 하여 선수쪽에서 진동준위가 높고, 선미쪽에서는 소음준위가 높다. 2. 진동분석 1) 진동변위는 주기관 cylinder head에서 100$\mu$m로 가장 크고, compass deck에서는 3$\mu$m로 가장 작다. 또 진동속도는 주기관 cylinder head에서 11mm/sec로 가장 빠르고, compass deck에서 0.07mm/sec로 가장 느리며, 이들은 모두 100Hz 이상에서는 급격한 감쇄를 보였다. 2) 진동가속도는 주기관 cylinder head에서 중심주파수 1KHz, 1.1mm/sec 상(2) 로 가장 빠르고 compass deck에서 30Hz, 0.05mm/sec 상(2) 로 가장 느리다.

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역설계를 통해 BIM 구축시에 3D 모델링에 대한 세밀도(LoD) 정립 - 지상 LiDAR 활용한 3D 모델링 연구 중심 - (Definition of 3D Modeling Level of Detail in BIM Regeneration Through Reverse Engineering - Case Study on 3D Modeling Using Terrestrial LiDAR -)

  • 채재현;이지영
    • 한국BIM학회 논문집
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    • 제7권4호
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    • pp.8-20
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    • 2017
  • When it comes to set up the BIM through the reverse engineering, the level of detail(LoD) required for finalized outcomes is different from each purpose. Therefore, it is necessary to establish some concrete criteria which describe the definition of LoDs on 3D modeling for the purpose of each reverse engineering. This research shows the criteria of the 1) positional accuracy, 2) generalization level, 3) scale level, 4) scope of description, and 5) the area available for application by classifying LoD from 1 to 6 on 3D modeling for each purpose of reverse engineering. Moreover, through applying those criteria for the 3D point cloud dataset of building made by terrestrial LiDAR, this research finds out the working hour of 3D modeling of reverse engineering by each LoDs according to defined LoD criteria for each level. It is expected that those findings, how those criteria of LoD on reverse engineering are utilized for modeling-workers to decide whether the outcomes can be suitable for their budget, applicable fields or not, would contribute to help them as a basic information.

LOD(Level-of-detail)이용한 3D객체의 동적 계층의 충돌 검사 성능 향상 (LOD(Level-of-Detail) using Dynamic-Hierarchies of collision detection efficiency improvement in 3D object)

  • 이춘호;김태용
    • 한국HCI학회:학술대회논문집
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    • 한국HCI학회 2007년도 학술대회 1부
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    • pp.963-968
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    • 2007
  • 본 논문에서는 현재 3D 그래픽뿐만 아니라 게임에서 정확한 충돌감지(collision-detection)나 컬링(culling)등은 3D공간에서 이러한 표준객체를 중심으로 많은 연구가 이루어지고 있다. 3D그래픽 분야에서 H/W의 놀라운 발달과 3D게임을 즐기는 게이머들이 좀 더 사실적인 표현에 깊은 관심을 가지고 있다. 90년대 중반 이후로 많이 연구되어진 3D 게임 엔진과 알고리즘 중에서 표준 3D 객체의 다양한 충돌 알고리즘을 분석하고, 기존의 3D 객체의 단순한 Hierarchies 구조에서 탈피하여 3D공간상에서 LOD(Level-of-Detail) 알고리즘을 이용하여, 3D객체가 3D 공간상에서 충돌검사의 성능을 향상시켜서 3D 게임의 필수 요소인 3차원 공간상의 효율적인 렌더링과 사실적인 표현의 알고리즘을 제안하여 실시간을 중요시 하는 3D 게임에서 사실감과 효율성을 높일 수 있게 제안한다.

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Vitamin D², Thyroxine, 및 Calcium gluconate가 백서악하선적출로 인한 혈중 Calcium농도변화에 미치는 영향

  • 정동균;박노희;김중기
    • 대한치과의사협회지
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    • 제12권12호
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    • pp.919-923
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    • 1974
  • Serum calcium level was decreased by submaxillary gland removal in rate. To investigate the mechanisms involved in the above change, the authors examined the effects of thyroxine, vitamin D₂, and calcium gluconate, which influence the metabolisms of calcium and submaxillary gland, on the serum calcium level of the intact and submaxillary gland removal rats. The results were as follows: 1) Serum calcium level decreased by submaxillary gland removal. 2) Vitamin D₂, increased the serum calcium level significantly. 3) Thyroxine falied to recover the decreased serum calcium level induced by submaxillary gland removal to the control level. 4) In submaxillary gland removal rats, vitamin D₂ failed to increase the serum calcium level. 5) In thyroxine administered rats for 55 days, of which submaxillary glands were removed, vitamin D₂ failed to increase the serum calcium level. 6) The serum calcium level in intact rats was increased slightly, but increased significantly in submaxillary gland removal rats shortly after intravenous injection of calcium gluconate.

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소음측정방법에 따른 평가소음도 비교 (A Comparison of Noise Level by Noise Measuring Methods)

  • 심철구;노재훈;박정균
    • 한국산업보건학회지
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    • 제5권2호
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    • pp.128-136
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    • 1995
  • The purpose of this study is to evaluate the difference of noise level according to noise measuring methods in the noisy working environments. Sound pressure level(SPL), equivalence sound level(Leq) and personal noise exposure dose(Dose) in the fifty-nine unit workplaces of the twenty-eight industries were measured and relating factors which were affected noise level were investigated. The results were as follows ; 1. The noise levels were $88.70{\pm}5.68dB(A)$ by SPL, $89.07{\pm}5.41dB(A)$ by Leq and $89.07{\pm}5.69$ by Dose. The differences of noise levels by three measuring methods were statistically significant(P<0.001) by repeated measure ANOV A. 2. Comparing with noise levels by general classes of noise exposure, noise levels of continuous noise were $89.14{\pm}5.19dB(A)$ by SPL, $89.45{\pm}4.65dB(A)$ by Leq and $90.04{\pm}5.09$ by Dose. Noise levels of intermittent noise were $87.90{\pm}6.52dB(A)$ by SPL, $88.40{\pm}6.63dB(A)$ by Leq and $90.10{\pm}6.80$ by Dose. The differences noise level of noise measuring methods by general classese of noise exposure were statistically not significant by repeated measure ANOV A. 3. Interaction between general classese of noise exposure and noise measuring methods for noise level was not statistically significant by repeated measure ANOVA. And the noise level by noise measuring methods were statistically significant by repeated measure ANOV A(P<.001) 4. Comparing with noise levels by unit workplace size, noise levels of large unit workplace were $90.73{\pm}5.87dB(A)$ by SPL, $91.32{\pm}5.50dB(A)$ by Leq and $91.82{\pm}6.06$ by Dose and noise levels of middle unit workplace were $88.31{\pm}5.26dB(A)$ by SPL, $88.41{\pm}4.83dB(A)$ by Leq and $89.69{\pm}5.05$ by Dose. And noise levels of small unit workplace were $94.89{\pm}4.10dB(A)$ by SPL, $85.35{\pm}4.11dB(A)$ by Leq and $86.87{\pm}4.98$ by Dose. The noise level differences of noise measuring methods by unit workplace size were statistically significant by repeated measure ANOV A(P<.05). 5. The noise level by noise measuring methods were statistically significant by repeated measure ANOV A(P<.001). But Interaction between workplace size and noise level measuring methods for noise level was not statistically significant by repeated measure ANOVA. According to the above results, there was a difference of the noise level among the three measuring methods. Therefore we must use the personal noise exposure dose using by noise dose meter, possible, to prvent occupational hearing loss in noisy working environment.

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