• Journal of Mechanical Science and Technology
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• 제17권2호
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• pp.207-214
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• 2003

The fatigue behaviour of six different hollow section T-joints subjected to out-of-plane bending moment was investigated experimentally using scaled steel models. The joints had circular brace members and rectangular chord members. Hot spot stresses and the stress concentration factors. (SCFs) were determined experimentally. Fatigue testing was carried out under constant amplitude loading in air. The test results have been statistically evaluated, and show that the experimental SCF values for circular-to-rectangular (CHS-to-RHS) hollow section joints were found to be below those of circular-to-circular (CHS-to-CHS) hollow section joints. The fatigue strength, referred to experimental hot spot stress, was in reasonably good agreement with referred fatigue design codes for tubular joints.

• 한국식품영양과학회지
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• 제27권5호
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• pp.881-889
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• 1998

For the application of the commercially modified starch in frozen and retort foods, apparent viscosity and water loss were measured at each stages of heating, sterilization and freezing-thawing stages. Apparent viscosity showed the exponential increase with concentration and the slopes of apparent viscosity against concentration in the Firm-Tex(hydroxypropyl distarch phosphate), Hi-Flo(acetylated distarch adipate) and Colflo 67(acetylated distarch adipate) from waxy maize starch were higher than those of Amyloacetate M20(starch acetate) and X-amylo 250(distarch phosphare) from potato starch. In the presence of 1 or 2% NaCl, X-amylo 250 among modified starches showed the increase in water loss and the decrease in apparent viscosity, whereas Colflo 67, Hi-Flo and Firm-Tex were little affected by NaCl. In the presence of 1 or 2% sucrose, water loss and apparent viscosity of the modified starches were not affected. In the range of pH 4~8, water loss and apparent viscosity of the modified starches had no change but the differences were detected to some extent between each of heating, sterilization and freezing-thawing stages. In the apparent viscosity and water loss of the modified starches after 3 week storage from heating and sterilization, Hi-Flo, Amyloacetate M20 and X-amylo 250 were not changed at the storage period, and the overall acceptability of retort food containing the modified starches such as Firm-Tex and Amyloacetate M20 were favored more than others. In the apparent viscosity and water loss of the modified starches which have been frozen and thawed three times repeatedly, Colflo 67, Hi-Flo and Firm-Tex were not changed in freezingthawing, and the overall acceptability of frozen food containing Firm-Tex was most favored.

• Nutritional Sciences
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• 제1권1호
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• pp.52-55
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• 1998

This study was performed to investigate the effect of dietary iron intake on the immune status of male college students. Twenty healthy male university students participated in the study. The mean age of the subjects was 22.6 years old, mean height was 173.3 cm and mean body weight was 68.4 kg. The mean daily iron intake of the subjects was 19.9 mg, 158.1% of the Korean recommended dietary allowances (RDA). The blood iron status and immune responses of the subjects were analyzed and compared between the high dietary iron group consuming more than 100% of the RDA of iron (Hi-Fe) and the low dietary iron group consuming less than 100% of the RDA of iron (Low-Fe). The serum iron concentration and percent saturation of transferrin were within the normal range in both groups. However, the Hi-fe group had higher serum iron and percent saturation of transferrin than the Low-fe group (p<0.05). When differential white blood cell counts were compared, the Low-Fe group had a lower percentage of neutrophils than the Hi-Fe group (p <0.1). The plasma IL-2 concentration, immunoglobulin levels and lymphocyte subsets were not affected significantly by the differences in iron intake as shown in this study. Serum iron had a positive correlation with monocyte percentage but had a negative correlation with IgM concentration. The results of this study suggest that slightly-low dietary iron intake without anemia has no effects on the cell-mediated and humoral immunities of healthy male university students. However, natural defenses, such as neutrophils and monocytes, seem to be more sensitively affected by changes in dietary iron intake.

• 대기
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• 제23권2호
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• pp.221-229
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• 2013

There has been an increasing need to assess the effects of climate change on human health. It is hard to use climate data to evaluate health effects because such data have a grid format, which could not represent specific cities or provinces. Therefore, the grid-format climate data of South Korea based on RCP (Representative Concentration Pathway) scenarios were modified into area-format climate data according to the major cities or provinces of the country, up to the year 2100. Moreover, heat index (HI) and discomfort index (DI) databases were developed from the modified climate database. These databases will soon be available for experts via a Website, and the expected HI and DI of any place in the country, or at any time, can be found in the country's climate homepage (http://www.climate.go.kr). The HI and DI were analyzed by plotting the average indices every ten years, and by comparing cities or provinces with index level changes, using the geographic information system (GIS). Both the HI and DI are expected to continually increase from 2011 to 2100, and to reach the most dangerous level especially in August 2100. Among the major cities of South Korea, Gwangju showed the highest HI and DI, and Gangwon province is expected to be the least affected area in terms of HI and DI among all the country's provinces.

• 사회복지연구
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• 제43권2호
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• pp.319-344
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• 2012

본 연구는 2010년 국민건강영양조사 원자료를 이용하여 의료이용 형평성지수인 집중지수와 Hiwv지수를 성별, 연령, 지역의 하위집단에 따라 집단 간 차이(Between)에 의한 부분과 집단 내부의 불평등(Within)에 의한 부분, 그리고 잔여 부분(R)으로 분해하였다. 본 연구의 분석결과는 다음과 같다. 첫째, 외래이용 횟수에서 남녀의 집단 간 차이가 Hiwv지수에 미치는 영향은 0으로 나타났다. 반면 외래비용에서는 Hiwv지수 .1035 중 여성들의 집단 내부불평등이 .0441을 설명하고 있어 빈곤여성들의 의료서비스 저이용이 의료이용 형평성에서 중요한 문제가 됨을 알 수 있었다. 둘째, 외래이용 횟수 형평성에 연령집단의 차이는 크게 영향을 미쳤는데, 미세한 양이지만 Hiwv지수 -.0107에서 대부분인 -.0085을 설명하고 있다. 셋째, 외래비용의 Hiwv지수에는 집단 내부의 불평등 특히, 노년층의 내부 불평등이 .0253을 설명하여 설명력이 크게 나타났다. 넷째, 외래비용의 Hiwv지수에 지역의 내부 격차(Within)가 가장 크게 영향을 미쳐서 Hiwv지수 .1035 중 .0569를 설명하였으며, 이 중 대부분인 .0535를 도시지역의 불평등이 설명하였다. 분석결과를 종합하면 분석된 집단범주 중 외래이용 횟수의 형평성에 가장 크게 영향을 미치는 집단은 연령집단이었으며, 외래비용에서는 집단 간 격차보다 집단 내부의 불평등이 더 크게 영향을 미치는 것으로 나타났다. 빈곤여성일수록, 빈곤노인일수록, 도시빈민일수록 기대비용에 못 미치는 외래진료비를 지출하고 있음을 나타냈는데, 이들에 대한 의료비지원 정책이 요구된다고 하겠다.

• 한국초지조사료학회지
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• 제10권2호
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• pp.70-76
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• 1990

The present study elucidates the effect of drught by polyethylene glycol solution on germination of five temperate and two tropical grasses. The results obtained can be summarized as follows: 1. The germination percentage of seven grasses decreased with increasing concentration of polythylene glycol. 2. The germination pattern hi higher concentration of polyethylene glycol showed similar trends to the emergence pattern under drought stress in soil condition. 3. The treatment of 30g is most useful at this study. Therefore, polythlene glycol was the appropriate to creat the drought condition of soil.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 춘계학술대회
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• pp.69-72
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• 2007

The objective of this work was to study the properties of purification of two liquid phase for exclusion of impurities in each phase. The experiments for process variables were carried out in the temperature range($H_{2}SO_{4}$ phase: $413{\sim}513$ K, $HI_{x}$ phase: $353{\sim}453$ K) and in the $N_{2}$ flow rate range($H_{2}SO_{4}$, $HI_{x}$ phase: $50{\sim}200$ mL/min). As the results, it is appeared that the principles of $H_{2}SO_{4}$ phase purification was due to stripping, evaporation and reverse bunsen reaction and $HI_{x}$ phase purification was due to stripping and reverse bunsen reaction. In purification of $H_{2}SO_{4}$ phase, the concentration rate of $H_{2}SO_{4}$ phase was controled by temperature but the temperature had few effects on yield of $H_{2}SO_{4}$. In purification of $HI_{x}$ phase, we observed products of side reactions($H_{2}S$, S) over 433 K. The purity of $HI_{x}$ phase was increased with increasing $N_{2}$ flow rate because impurites were decreased with increasing conversion of reverse reaction.

• 태양에너지
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• 제6권2호
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• pp.15-21
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• 1986

In this study, an experimental double diffusive thermohaline system heated from below was constructed and the phenomena of each layer developed in the system were observed. The experiment was performed with the initial salt concentration gradient of $-436.2kg/m^4$ and the net heat flux of approximately $176w/m^2$. An electroconductivity-temperature probe was made and used for the measurements of salt concentration. As the result of this study, it was found that the salt concentration decreased in the bottom mixed layer and increased in the top mixed layer during the experiment while the salt concentration gradient in the diffusive layer unchanged. It was also found that the interfacial boundary layers were due largely to variations in salt concentration rather than temperature.

• 접착 및 계면
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• 제10권4호
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• pp.174-181
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• 2009

고 고형분 점착제의 점도 개선을 위해 seed 중합을 이용하여 수용성 저점도 점착제를 중합하였다. Seed 바인더 중합 중 최적 중합 조건을 산출하고, 점착제 중합 시 seed 바인더와 acrylic acid의 함량을 변화시켜 점도변화와 피착면에 대한 점착박리강도를 측정하여 다음과 같은 결과를 얻었다. 점착제 중합에서 seed 바인더의 함량이 7 wt%/monomer일 때 60%의 고형분에서 2,100 cps의 낮은 점도를 나타내고 평활한 점착제 필름을 제조할 수 있었다. Acrylic acid함량 변화에 따른 기계적 물성 측정에서는 4 wt%/monomer의 acrylic acid를 사용 했을 때 우수한 점착박리강도와 유지력을 나타내었다.

• 한국식품과학회지
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• 제38권6호
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• pp.810-815
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• 2006

본 실험에서는 애기달맞이꽃(Oenothera laciniata Hill)를 80% EtOH로 추출하고 추출물을 극성에 따른 용매 분획을 실시하여 분리된 분획의 총 페놀화합물 함량과 DPPH radical 소거, xanthine oxidase 저해활성, superoxide 소거활성 및 nitric oxide 소거활성 및 세포독성 등의 생리 활성을 측정하였다. 본 연구를 통해 애기달맞이꽃은 산소 유리기의 자유기를 소거할 수 있는 우수한 생리 활성물질을 다수 함유하고 있음을 확인 할 수 있었으며 분획 레벨에서의 활성이 대조구 성분 못지않게 우수하게 나타났다. 또한 총 폴리페놀 함량과 세포독성이 가장 높게 나타난 EtOAc 분획물을 농도별로 HL-60세포에 처리한 결과, 세포성장 억제는 농도 의존적으로 나타났으며, 따라서 세포성장 억제효과가 apoptosis 유도에 의한 것이지를 확인하고자, apoptosis 유도에 의하여 나타나는 현상의 하나인 DNA 단편화 현상을 비롯하여 세포 형태학적 변화 및 유동세포분석기를 통한 DNA content을 측정하였다. 그 결과, 애기달맞이꽃 추출물에 의한 세포증식 억제효과는 apoptosis유도에 의해 세포사멸이 일어남을 확인할 수 있었다.