• Korea-Australia Rheology Journal
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• 제14권2호
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• pp.77-86
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• 2002

A microscopic theoretical study is performed to predict the rheological properties of human blood in the low concentration limit. The shear thinning behavior of blood in the low shear limit is studied by considering the aggregate formation of red blood cells, which is called the rouleaux formation. Then the constitutive equations of blood in the high shear limit are derived for various flow situations by considering the unique features of deformation of blood cells. Specifically, the effects of the surface-area-preserving constraint and the lank-treading motion of blood cells on the rheological properties are studied.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 지반환경 및 준설매립에관한 학술세미나
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• pp.122-142
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• 2001

Mudstone which is in po-hang area, made from bedrock under a tropical ocean environment, The mudstone has a tendency to be weathered and swelled when it is exposed to the atmosphere. In addition the clay material on the surface shows highly compressive property that causes a lot of engineers problem during embanking and cutting. This report covers alternative methods to solve those problems by understanding engineering characteristics of the site through precise filed investigations and predicting the problems during construction.

• 한국지구과학회지
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• 제21권3호
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• pp.287-301
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• 2000

본 연구진은 포항지역을 중심으로 1995년부터 1997년의 3년간 오존존데로 관측한 고도별 오존농도 및 오존전량 자료를 이용하여 오존의 수직분포특성에 대한 연구를 수행하였다. 오존의 수직분포를 체계적으로 밝히기 위해, 지상(100m), 대류권(10km), 하부 성층권(20km), 중부 성층권(30km)을 대표 고도로 설정하여 오존농도의 시 ${\cdot}$ 공간적 분포특성에 대한 비교분석을 시도하였다. 지상(100m) 오존의 경우, 포항제철이 인접해 있음에도 불구하고, 전반적으로 청정지역에서와 유사한 농도분포를 유지하였다. 봄과 여름에 높고 가을과 겨울에 낮은 농도분포는 기상인자들과의 상관성을 고려할 때, 대체로 광화학 반응에 의한 결과로 보여진다. 대류권(10km) 및 하부 성층권(20km)의 경우 춘고하저(春高夏低)의 전형적인 북반구 대류권 오존의 시간적 경향성을 나타내었다. 이는 고도별 오존농도간의 분석결과 성층권 오존의 대류권 이동 및 광화학 반응과 역전층 형성에 의한 결과로 추정된다. 중부 성층권(30km) 오존의 경우 지상 오존의 농도분포 경향과 매우 유사한 월주기 및 계절주기를 취하였다. Brewer 분광광도계에 의한 오존전량은 성층권 오존량 (Umkehr 법)에 의해 크게 좌우되며, 오존전량은 유해자외선 (UV-B)과의 상관성은 미미하나, 운량과는 음의 상관성을 갖는 것으로 나타났다. 본 연구의 결과 지상권뿐만 아니라 대류권 및 성층권 오존의 시간적 특성을 이해하는데 있어 포항이 해안도시라는 지리학적인 요인이 매우 중요하다는 점을 확인할 수 있다.

• Animal cells and systems
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• 제1권2호
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• pp.305-311
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• 1997

Dermaptera was investigated, examined and reviewed in taxonomy and for distribution in Youngnam region. Based on the data, the local species groups were measured to choose priority-conservation-area by taxonomic root weighting and distribution analysis at 232 geographical conservation units. Eleven species belonging to 4 families and 8 genera were recorded mounting up to 68.75% of species diversity known in Korea. Found remarkably were the rare and endangered Challia fletcheri Burr at Sobaek Mountain National Park, and unusually Anisolabis maritima (Bonelli) in Taegu, Euborellia pallipes (Shiraki) at Island Geoje and E. plebeja (Dohrn) at Hwanho near Pohang. The highest species diversity was found at the temple Huibang area at Sobaek Mountain National Park with 8 species, which was measured also as the primary priority-conservation-area with 83.41 % of accumulated taxonomic root weighting indices in percentage. Geoje and Hwanho both measured as 12.18% of accumulated taxonomic root weighting index in percentage and complimentary to Sobaek Mountain National Park but supporting 5 and 3 species, respectively. The priority goes to the geographical conservation unit supporting higher species richness between two geographical conservation units in comparison. By the rule, the second priority-conservation-area should be Geoje and the third Hwanho. It is, thus, demonstrated how 11 species can be all conserved by choosing 3 priority-conservation-areas out of 232 geographical conservation units to maintain maximum species in minimum areas.

• 한국전자파학회논문지
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• 제24권3호
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• pp.310-315
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• 2013

본 논문에서는 전력 케이블의 전파상수를 추출하는 2-port time-domain reflectometry(TDR) 방법을 제안한다. 케이블을 투과하는 펄스 신호를 시간 영역에서 측정하고 주파수 영역에서 분석하여 전파상수를 추출하였다. 22.9 kV 325 $mm^2$ XLPE 케이블의 전파상수를 2.14 GHz까지 추출하고 network analyzer 로 측정한 케이블의 $S_{21}$을 비교하여 2-port TDR 방법의 타당성을 입증하였다. 그 결과, 기존의 TDR 방법보다 측정 가능한 상한 주파수가 증가하고, 고주파수에서 오차가 줄어드는 것을 확인하였다.

• 한국지진공학회논문집
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• 제22권3호
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• pp.169-174
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• 2018

A total of 594 reservoirs (17%), which are managed by KRC, equipped with earthquake-resistant facilities whereas remaining ones did not. In addition, reservoirs were placed without the effect of geological structures (i.e., fault and lineament). Therefore, development on technique for alleviating the potential hazards by natural disasters along faults and lineaments has required. In addition, an effective reinforcement guideline related to the geological vulnerabilities around reservoirs has required. The final goal of this study is to suggest the effective maintenance for the safety of earth fill dams. A radius 2 km, based on the center of the reservoir in the study area was set as the range of vulnerability impacts of each reservoir. Seismic design, precise safety diagnosis, seismic influence and geological structure were analyzed for the influence range of each reservoir. To classify the vulnerability of geological disasters according to the fault distribution around the reservoir, evaluation index of seismic performance, precise safety diagnosis, seismic influence and geological structure were also developed for each reservoir, which were a component of the vulnerability assessment of geological disasters. As a result, the reservoir with the highest vulnerability to geological disasters in the pilot district was analyzed as Kidong reservoir with an evaluation index of 0.364. Within the radius of 100km from the epicenter of the Pohang earthquake, the number of agricultural infrastructure facilities subject to urgent inspections were 1,180 including reservoirs, pumping stations and intakes. Four reservoirs were directly damaged by earthquake among 724 agricultural reservoirs. As a result of the precise inspection and electrical resistivity survey of the reservoir after the earthquake, it was reported that cracks on the crest of reservoirs were not a cause of concern. However, we are constantly monitoring the safety of agricultural facilities by Pohang aftershocks.

• 분석과학
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• 제14권2호
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• pp.147-158
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• 2001

고분해능 가스크로마토그래프/고분해능 질량분석기를 이용하여 시화공단 지역 근로자와 일반주민의 혈액에서 다이옥신류를 분석하였다. 평균 다이옥신류의 농도는 근로자가 일반주민보다 높았다. 근로자와 일반주민의 평균 다이옥신 TEQ 농도는 각각 40.3 pg I-TEQ/g lipid, 16.6 pg I-TEQ/g lipid였고, 전체 PCBs 농도는 각각 174.1 ng/g lipid, 151.0 ng/g lipid였다. 주성분분석을 한 결과, 근로자와 일반주민의 다이옥신 이성질체 분포는 구별되었지만, 모두 식품류에서의 분포와 유사하였다. 각 개인의 일일 다이옥신 섭취량을 계산했을 때 40%만이 WHO에서 제시한 1-4 pg I-TEQs/kg bw/day의 허용범주를 만족하였다.

• 한국항해항만학회지
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• 제29권10호
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• pp.821-826
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• 2005

2006년 영일만 신항이 개장될 경우 포항항 진입 수역은 선박 통항량이 증가하고 중대형 선박들의 입출항이 가속화될 것이다. 그러나 포항항 일부 진입 수역에는 여전히 항행 위험 요소가 존재하고 있다 즉, 호미곶 인근 해역에서의 무질서한 항행 및 교통이 폭주하고 있어 통항 안전성을 고찰하기 위하여 해상교통조사를 실시하였다. 또한 해상교통조사 결과를 선종별 및 톤수별로 통계 처리하고 통항 선박의 항적 분포 등을 토대로 통항 선박의 주요 통항로 및 통항 특성을 분석하였으며, 향후 포항항 진입 수역의 항로지정에 활용하고자 한다.

• 한국대기환경학회지
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• 제21권6호
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• pp.573-583
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• 2005

Fugitive dust, which is emitted in the ambient air without first passing through a stack or duct designed to control flow, is frequently generated by means of wind erosion from storage yards at Pohang Steel Wokrs. The size distribution of fugitive dust is mostly in the range of coarse particulate which is deposited as soon as emitted and less harm to human health; however $20\%$ of fugitive dust contains PM 10 known as one of most harmful airborne pollutant. Consequently, effective control and reduction of fugitive dust is strongly requested by the local society, but it is not easy so far because the generation and dispersion of fugitive dust highly depends on meteorological conditions, and it being occurred for irregularity. This research presented a fugitive dust control system for each meteorological condition by providing statistical prediction data obtained from a statistical analysis on the probability of generating the threshold velocity at which the fugitive dust begins to occur, and the frequency occurring by season and by time of the wind direction that can generate atmospheric pollution when the dispersed dust spreads to adjacent residential areas. The research also built a fugitive dust detection system which monitors the weather conditions surrounding storage yards and the changes in air quality on a real-time basis and issues a warning message by identifying a situation where the fugitive dust disperses outside the site boundary line so that appropriate measures can be taken on a timely basis. Furthermore, in respect to the spraying of water to prevent the generation of fugitive dust from the storage piles at the storage yard, an advanced statistical meteorological analysis on the weather conditions in Pohang area and a case study of fugitive dust dispersion toward outside of working field during $2002\∼2003$ were carried out in order to decide an optimal water-spraying time and the number of spraying that can prevent the origin of fugitive dust emission. The results of this research are expected to create extremely significant effects in improving surrounding environment through actual reduction of the fugitive dust produced from the storage yard of Pohang Steel Works by providing a high-tech warning system capable of constantly monitoring the leakage of fugitive dust and water-spray guidance that can maximize the water-spraying effects.

• 한국의류산업학회지
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• 제8권5호
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• pp.597-603
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• 2006

This study was aimed to find out the problems of wearing flame-proof clothing and to analytically assess functional working-clothes, thus to propose a new design. We carried out a questionnaire with workers in the field and evaluated the facility for wearing, the sensation of wearing and clothing microclimate in the environmental chamber. We found out the problems were in the parts of neck, armpits, armhole, sleeve, crotch and suspenders. Thermal sensation, wet sensation and comfort sensations were evaluated to be 'hot', 'wet' and near to discomfort', respectively. Therefore, improvement of movement and air permeability is needed. If we can add gusset on armpit for air permeability, this gusset will enable to enlarge the surface in armpit area and finally give a movement efficiency. We suggested several new partly modified design for flame-proof clothing which can be applied to other protective clothing for improvement. This must be further considered in the ergonomic evaluation of new proposed functional working-clothes as well as in the suggestion of design.