• 국제초고층학회논문집
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• 제7권4호
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• pp.397-408
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• 2018

In a recent tragic fire incident, the Plasco Tower collapsed after an intense outburst of fire lasting for three and a half hours and claiming the lives of 16 firefighters and 6 civilians. This paper will present continuing collaborative work between Hong Kong Polytechnic University and Queen's University in Canada to model the progressive collapse of the tower. The fire started at the 10th floor and was observed to have travelled along the floor horizontally and through the staircase and windows vertically. Plasco Tower was steel structure and all the steel sections were fabricated by welding standard European channel or angle profiles and no fire protection was applied. Four internal columns carried the loads transferred by the primary beams, and box columns were constructed along the perimeter of the building as a braced tube for resisting seismic loading. OpenSees fibre-based sections and displacement-based beam-column elements are used to model the frames, while shell elements are used for the reinforced concrete floor slabs. The thermal properties and elevated temperature mechanical properties are as recommended in the Eurocodes. The results in this preliminarily analysis are based on rough estimations of the structure's configuration. The ongoing work looks at modeling the Plasco Tower based on the most accurate findings from reviewing many photographs and collected data.

• 한국습지학회지
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• 제16권4호
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• pp.379-388
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• 2014

본 연구는 2단(수직 및 수평 흐름) 복층여재(모래와 제올라이트 그리고 모래와 굴 껍질) 갈대 인공습지에 생활하수를 간헐적으로 주입하였을 때 각 수질항목별 처리효율 평가이다. 하수는 수리학적 부하량 $314L/m^2{\cdot}day$(수직 흐름 인공습지 기준)를 하루 4(10분 동안 주입 후 5시간 50분 동안 중단)회 균등하게 간헐적으로 주입하였다. 그 결과 유출수의 pH는 수평 흐름 인공습지 굴 껍질 층의 높이에 크게 영향을 받았으며 굴 껍질 층의 높이가 200 mm일 때 pH 6.24를 보였다. DO(oxygen demand)는 유입수(0.19 mg/L)보다 수직 흐름 인공습지 유출수(7.65 mg/L)에서 높았다가 수평 흐름 인공습지 유출수(6.49 mg/L)에서는 다시 낮아졌다. 그리고 여름보다 겨울에 높았다. 또한 OTR(oxygen transfer rate)은 수직 흐름 인공습지 $57.15g\;O_2/m^2{\cdot}day$ 그리고 수평 흐름 인공습지 $5.65g\;O_2/m^2{\cdot}day$로 나타났다. $NH_4{^+}$-N의 처리효율은 80.17% (유출수 농도 6.01 mg/L)로 전부를 제올라이트로 충진하였을 경우(타 연구)와 비교하여 낮았지만 수직 흐름 인공습지 제올라이트 300 mm 충진 층으로도 하수처리에서 요구되는 방류수질의 T-N 농도(20 mg/L)까지 안전성 있게 처리할 수 있을 것으로 예측된다. 각 항목별 평균 처리효율은 유출수에서 SS 88.09%, BOD 88.12%, $COD_{Cr}$ 83.11%, $COD_{Mn}$ 85.58%, T-N 57.21%, $NH_4{^+}$-N 80.17%, T-P 86.73%를 보였다. $NO_3{^-}$-N의 농도는 수직 흐름 인공습지 유출수에서 보다 수평 흐름 인공습지 유출수에서 감소하였다. 유출수 중 T-N의 반 이상이 $NO_3{^-}$-N(7.92 mg/L)으로 잔존하였으며 $NO_2{^-}$-N은 평균 0.90mg/L이었다. T-P의 처리효율은 굴 껍질의 충진 층 높이가 800 mm에서 93.24%, 500 mm에서 86.30% 그리고 200 mm에서 55.44%로 굴 껍질 충진층의 높이에 비례하였다.

• 대한치과보철학회지
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• 제47권2호
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• pp.156-163
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• 2009

연구목적: 4종 구치용도재관(Full-porcelain-occlusal-surfaced PFG, Half-porcelain-occlusal-surfaced PFG, Empress 2, Ice Zirkon)과 선별된 한국음식의 fracture load와 dynamic cyclic load를 측정하여 구치용 도재관에 파절을 일으킬 가능성이 있는 한국음식을 선별하는데 있다. 연구재료 및 방법: 4종의 각 porcelain 보철물 system 당 15개의 축대칭을 이루는 crown을 제작했다. 이때 occlusal reduction은 1.5-2.0 mm로 했다(중심부 1.5 mm, 교두부 2.0 mm). 각 15개의 시편의 교합면 중앙부에 직경 5 mm의 stainless steel ball을 위치시킨 후 Instron 4465 universal testing machine(Instron, Norwood, MA USA)을 이용하여 5 mm/min의 crosshead speed로 수직 부하를 주어 파절을 일으키는 최대 부하(N)를 기록했다. 이후, 한국음식 중 삶은 게, 닭(뼈포함), 소갈비(뼈포함), 마른 오징어, 건멸치, 사탕, 호두껍질을 표본으로 설정하고 이들을 파절시키는 최대 부하(N)를 universal testing machine(Instron 4465) 에서 측정하여 기록했다. 각 항목당 15번을 측정했다. 음식물을 파절시킬 때 필요한 최대부하와 각 보철물의 파절저항을 비교하여 한국의 식습관과 도재를 이용한 보철물 파절의 상관관계를 조사하였다. fracture loads는 analysis of variance 와 Post Hoc tests를 이용해서 분석하였다($\alpha$=0.05). 차후에 위에서 얻은 결과를 바탕으로 Hydraulic Dynamic Fatigue Testing Machine(858 Bionix II, MTS systems, Eden Prairie, MN USA)를 이용하여 4종의 각 porcelain 보철물 system당 5개의 crown에 14Hz Cyclic Load를 가하여 crown에 파절을 일으키는 masticatory cycle수를 알아 보았다. Load 수치는 41.0 N(건멸치 파절강도), 169.0 N(마른오징어 파절강도), 382.9 N(닭뼈 파절강도), 2224.8 N(사탕 파절강도)로 설정하였다. 결과: 95% confidence intervals for mean fracture load는 2599.3-2809.1 N(완전도재교합면 PFG), 3689.4-3819.9 N(반도재교합면 PFG), 1501.2-1867.9 N(Ice Zirkon), 803.2-1188.5 N(Empress 2)로 나왔고 95% confidence intervals for dynamic cyclic load on fracture는 instron 상에서 도재보철물에 파절을 일으키지 않은 load인 2224.8 N(사탕 파절강도)와 382.9 N(닭뼈 파절강도)로 실험했을 때, 2224.8 N에서 4796.8-9321.2 cycles(완전도재교합면 PFG), 2224.8 N에서 881705.1-1143565.7 cycles(반도재교합면 PFG), 382.9 N에서 979993.0-1145773.4 cycles(Ice Zirkon), 382.9 N에서 564.1-954.7 cycles(Empress 2)로 나왔다. 결론: 통계학적으로 유의할 만한 차이가 그룹들 간 fracture load에서 나타났다. 한국음식물 중 소갈비(뼈포함)와 사탕(자두맛캔디)은 구치용 도재보철물을 파절시킬 가능성이 있는 음식물로 밝혀졌다. 단일수직부하에서는 파절이 생기지 않는 경우라 할지라도 dynamic cyclic load를 줄 경우 일정 주기 후에 파절이 생기는 결과를 얻을 수 있었다.

• 한국수산과학회지
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• 제18권2호
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• pp.180-194
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• 1985

The author investigated the history of oyster culture in Korea through examining old books and reports dealing with the fishery. Oysters have been produced in the all coastal areas in Korea, especially the center areas of production were the Hwangupo (Hamkyongbuk-do), Younghungman (Hamkyongnam-do), the estuary of Nakdonggang (Kyongsangnam-do), Kwangyangman, Haechangman, the estuary of Yongsangang (Chollanam-do), Yonghoto (Hwanghae-do) and the estuary of Uprockgang, where the large size oyster (more than 40cm in shell height) inhabited in form of groups. It was called by nine different names in the old times, Gul, Seukhwa and Moryeo were the most common names. The oyster was used as 46 kinds of medicinal stuff. The habitat forms of natural oyster can be distinguished to two types; one is that oyster is exposed to the air during the period of low tide (A-type), another is that oyster is not (B-type). The first oyster culture by the old books in Korea was started about 530 years ago as the bottom culture method derived from the A-type of oyster. After long years, the hanging culture method might have been started from the hint of the habitat form of B-type. The oyster culture in Korea developed based on the habitat forms of natural oyster at the biginning of 1900s. After World War II, the Korean government strongly recommded the laver farmers to culture oyster as relief measures. At that time, the stone culture method was mainly adopted. The quantity of oyster production is now about $15{\times}10^6{\sim}19{\times}10^6\;\frac{M}{T}$, and the half of oyster production including seed oyster is exported to the foreign countries.

• 수산해양기술연구
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• 제53권3호
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• pp.266-275
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• 2017

The maximum sustained yield (MSY) of shellfish caught through dredge fishery was 7,250 to 7,490 MT from 1990 to 1999, which was not affected by the construction of the Saemangeum Dike. The MSY from 2000 to 2016, under the influence of the dike, was 1,716 to 1,776 MT when the total annual fish catch was 1,000 MT or more, and 289 to 336 MT when it was less than 1,000 MT. The construction of the Saemangeum Dike led to a decrease in the catch volume of the offshore dredge fishery in Jeollabuk-do, to 4.2 to 23.7% of that before its construction. The allowable biological catch (ABC) was estimated to be 313 to 1,532 MT per year, which was about 72.3 to 94.3% less than before the construction of Saemangeum Dike. Currently, the dredge fishery in Jeollabuk-do relies on comb pen shells. For fishery management, the catch per vessel should be set at 51.0 MT/year or less, and the number of fishing vessels should be reduced to 22 as quickly as possible. Besides, in the long term, the number of current fishing vessels should be reduced to less than half in consideration of the comb pen shell collecting period in Jeollabuk-do.

• Animal Bioscience
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• 제37권6호
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• pp.1065-1076
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• 2024

Objective: This study aimed to assess the effects of dietary mulberry leaves on the growth, production performance, gut microbiota, and immunological parameters of poultry and livestock. Methods: The PubMed, Embase, and Scopus databases were systematically analyzed to identify pertinent studies up to December 2022. The effects of mulberry leaf diet was assessed using the weighted mean difference, and the 95% confidence interval was calculated using a random-effects model. Results: In total, 18 studies that sampled 2,335 poultry and livestock were selected for analysis. Mulberry leaves improved the average daily gain and reduced the feed/meat ratio in finishing pigs, and the average daily gain and average daily feed intake in chicken. In production performance, mulberry leaves lowered the half carcass weight, slaughter rate, and loin eye area in pigs, and the slaughter rate in chickens. Regarding meat quality in pigs, mulberry leaves reduced the cooked meat percentage, shear force, crude protein, and crude ash, and increased the 24 h pH and water content. In chickens, it increased the drip loss, shear force, 45 min and 24 h pH, crude protein, and crude ash. Mulberry leaves also affect the abundances of gut microbiota, including Bacteroides, Prevotella, Megamonas, Escherichia-Shigella, Butyricicoccus, unclassified Ruminococcaceae, Bifidobacterium, Lactobacillus, and Escherichia coli in poultry and livestock. Mulberry leaves at different doses were associated with changes in antioxidant capacity in chickens, and immune organ indexes in pigs. With respect to egg quality, mulberry leaves at different doses improved the shell strength, yolk color, eggshell thickness, and eggshell weight. However, moderate doses diminished the egg yolk ratio and the egg yolk moisture content. Conclusion: In general, dietary mulberry leaves improved the growth, production performance, and immunological parameters in poultry and livestock, although the effects varied at different doses.

• 대한가정학회지
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• 제11권3호
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• pp.329-344
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• 1973

The purpose of this study is to find how the mother's rearing patterns and attitudes influence on a child's social personality development. Many contemporary psychologists insist that mother's rearing attitudes and methods before age of six influence on child's social personality development a great deal. Freud divided the child's developmental stages into three : oral, anal, and phallic period. According to his assumptions the way of mother's feeding and weaning has very important relationship with the personality development through ora period and how to handle toilet training will greatly influence through anal period. In addition to this, Symonds declares that a mother's rearing attitudes will influence the establishment of social characteristics of the child. The moderate attitude-not too overprotective or rejective or submissive or dominate-is desirable. If mother's attitude declines to one aspect among these four kinds too much, the child would have chances to develop maladjusted social characteristics such as aggressiveness , submissiveness, dependency, and dominativeness. The hypotheses of this study were based on Freud and Symonds theory and tested by correlation and the difference of percentage. The results of the study were as follows : I. The relationship between rearing pattern and social characteristics 1. When the child has too strictly scheduled feeding time, he will have aggressive attitudes. 2. The longer the feeding period, the more dependency the child will have. 3. In case the toilet training was taken place too early or strictly, the child will withdraw into his shell. 4. When the child failed to perform the toilet training and was punished because of that, the child's personality will likely to be too submissive or aggressive. II. The relationship between mother's attitudes and social personality 1. When the mother's attitude is too overprotective the child showed withdrawn characteristics (r = 89) or dependency ( r = 24). 2. The child whose mother has too rejective attitude also showed withdrawn characteristics ( r = 31). As Sears insisted self-demanding schedule is recommendable and the weaning supposed to be started after age of one and a half years and finished around age of two. The toilet training which has rather severe consequences than the feeding methods should be started when the child is able to understand what is expected to him. Sears says that about two years after birth would be proper but individual difference should be considered. As a conclusion, Flexible and understanding attitudes and rearing methods is necessary for a sound establishment of social personality.

• 콘크리트학회논문집
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• 제17권1호
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• pp.85-94
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• 2005

PPS(post-tensioned precast concrete system)공법은 U자형 PC로 제작한 넓은 보와 PC 또는 현장 타설 콘크리트로 제작한 기둥으로 구성되며 PC 보와 기둥의 일체성 확보를 위하여 프리스트레스를 도입하였다. 본 연구는 PPS 공법 개발의 일부로 넓은 보의 기둥 폭 내부에 정착되어진 휨철근의 양에 따른 거동특성을 분석하고자 실험적 연구를 수행하였다. 실험체는 기둥 폭내, 외부에 위치한 휭 철근의 양을 달리한 정착비와 동일한 정착비내에서 철근과 긴장재의 양을 주요변수로 하여 대상건물의 내부접합부를 대상으로 1/2크기로 제작하였다. 그 결과 NEHRP 권고사항에서 규정한 한계변위각 0.035까지 내력저하 없이 충분한 내력을 보유하였으며, 보의 휨 파괴가 주요 파괴모드로 접합부에서 전단파괴는 일어나지 않았다. 그리고 넓은 보에 포스트텐션을 도입한 PPS 공법은 기둥 폭 내부의 정착비가 $35\%$인 경우 다소 높은 비틀림 응력을 나타내었으나, 기둥 폭 외부에 위치한 인장철근의 항복 이후 긴장재가 응력을 충분히 발휘함으로서 일체식 구조의 넓은 보-기둥 접합부와 달리 비탄성 이력거동을 통하여 에너지를 효과적으로 소산하였다. 또한 ACI의 proposed provisional standard의 PC 접합부 구조성능 평가지침에 의해 분석한 결과, 모든 실험체에서 허용기준을 모두 만족하고 있으며, 강도의 큰 저하 없이 연성적인 거동을 하고 있음을 알 수 있었다.

• Journal of Animal Science and Technology
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• 제44권1호
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• pp.55-60
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• 2002

본 연구는 식물성 phytase 처리수준이 산란계의 생산성에 미치는 영향 및 인 이용률에 미치는 영향을 검토하기 위하여 실시하였다. NRC 사양표준의 유효 인 요구량을 충족시킨 대조구와 무기태인 사용량을 50%로 제한한 처리구로 나누고, 각각의 처리구에 식물성 phytase를 각각 0.05%, 0.1% 및 0.2% 첨가하였다. 58주령의 갈색 산란계(ISA-Brown) 240수를 공시하여 총 6주간 사양실험을 실시하였고 산란종계를 이용하여 인 및 질소의 이용성을 측정하였다. 그 결과를 요약하면 다음과 같다. 1. 50% 무기태인 수준에서 식물성 phytase의 첨가에 따른 일당증체량, 산란율의 저하는 나타나지 않았다. 2. 50% 무기태인 수준에서 식물성 phytase 0.05% 첨가수준에서 일시적으로 난각질 저하 현상이 나타났으나 0.1% 이상 첨가수준에서는 난각질의 변화가 관찰되지 않았다. 3. 효소의 첨가수준이 증가함에 따라 P 배설량의 감소와 P 이용률이 개선되었다(P<0.05). 4. 식물성 phytase 첨가는 산란계의 성적 저하없이 사료내 무기태인의 사용량을 줄일 수 있음이 시사되었다.

• 한국식생활문화학회지
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• 제11권4호
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• pp.439-454
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• 1996

The present study investigated Bul-Chun-Wi Sacrificial Ritual (sacrificial service which has been handed down from generation to generation to worship the family ancestors in the period of $1400{\sim}1800$) and foods for the sacrificial service among fourteen head families in Andong area. The findings are as follows; 1. In Bul-Chun-Wi Sacrificial Rituals, family shrine has been maintained in good shape, and the table, dishes, and foods used in the rituals have not been changed so much until these days. 2. While vegetable soup is widely used as soup, one family uses the seaweed soup, the other soup mixed with meat, fish, and vegetable. Specially soybean-powdered soup, which is the distinguishable food in Andong area, has been used. 3. As a basic Ddock, mainly Si-Ru-Ddock(a steamed rice cake), piled up to 13-15 stacks, is used. Additional 7-9 kinds of Ddock are placed on top of the basic Ddock. 4. For grilled-meat food(Geuck), eight families use the raw meat, and one family uses the half-cooked meat. Recently, five families have used the cooked meat. Mostly used ones are meat-Geuck, fish-Geuck, chicken-Geuck, and the Geuck are not served one by one. Instead the Geuck are stacked in one dish designed for Geuck in order of meats from poultry, animal, fish, and shell. As the sub-dishes for rice, raw and cooked Geuck are used. 5. The number of stew (Tang) are 3 to 6 and 5 stews is the most popular. Commonly used stews are meat stew, fish stew, chicken stew, vegetable stew, blood stew, and organs stew. For the vegetable stew, buckwheat gel can be used. 6. As the fruit, chinese date, pear, nut and dried persimmons are the basic ones. The even number of 6 or 8 colorful fruits are used, while the odd number of 7 or 9 colorful fruits are used in three head families. 7. As Sik-Hae which is a drink and made from fermented rice, rice Sik-Hae or fish Sik-Hae has been necessarily used. 8. As raw meat dish, the liver of cow or meat is used. As a wrapping materials, the reticulum of a ruminant, green seaweed or thinly fried egg can be used.