• 건축역사연구
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• 제8권3호
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• pp.23-38
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• 1999

The purpose of this study is to analogize the appearance of Korean Ancient Architecture in view of the Stone Remains from 3 Kingdom Period to Unificated Shilla Period. But in these period, there is no building remains but some stupas and fine arts. Especially, there are many architectural appearance and revealing signature in these Historical Stone remains. Architectural elements which are analogized by stone remains what has value as historical materials by preservation of original form from 3 Kingdom Preiod to Unificated Shilla Period are as follows : 1) Platform, the representative characteristic of Korean traditional architecture, was frame structure and accumulate structure. And circular or square footing stood a same shape column on it is put on the platform. 2) In the case of column, there used entasis column and inclined column and circular chamfer technique was applied on the top side of it. Upper side of column, capital and head pentrating tie that small bearing block was put on the center of it was joined. And longitu야nal rest(長舌) supported a cross beam. Capital and small bearing block had no bottom heel, and heel side was curved and straight. Centered bracket structure was often used, and multi bracket structure is not used yet. Inward incline technique was used. 3) Inward opening pair door which had lintel, threshold, doorjamb was usually used, Fixing stone was used for structural safety, and circular handle and lock was used for decoration. Handrail was used on the edge of wooden floor for decorative effect and safety. 4) Square rafter and circular rafter were used in the same period and so did flying rafter. Double eaves and single eave were used in the same period but, single eave was usually used. In this period, square rafter was usually used. This would be studied more by comparing with Japanese wooden architecture. 5) Hipped roof was used and half-hipped roof was not used yet. In front of th hip, there are small sculpture called Jap-Sang(雜像), and windbell was hang on the end of the hip rafter. Concave roof tile, convex roof tile, round eaver tile, decorative tile at end of roof ridge were used. Lotus style was well used on the face of roof tile for decoration. From the results of this study, wooden architecture of Unificated Shilla period was simple compare to Koryo dynasty and Chosun dynasty but, it had some brilliant character. It was hard work that analogized the form of non-existent wood architecture of Ancient Korean period by restricted stone remains. But, in addition to the results of this study and research of old documentations, more study should be go on.

• Parasites, Hosts and Diseases
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• 제36권2호
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• pp.91-98
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• 1998

이 연구는 자연계 및 실험실 내 조건 하에서 오리극구흡충의 생활사를 관찰하기 위하여 수행하였다. 1992년 8월과 9월에 부산시 강서구에 소재하는 선암천에서 다랑의 물달팽이 (Rndix owe,cdwiacoreona)를 채집하였다. 채집한 물달팽이 중 106개를 파쇄법으로 조사하였던 바, 52개 (89.0%)에서 오리극구흡충의 유충 (레디아, 유미유충, 피낭유충)이 한 종류 이상씩 검출되었다. 물달팽이로부터 자연 유출되는 유미유충을 접촉감염시킨 물달팽이, 논우렁 및 미꾸리 중 물달팽이와 미꾸리에서 피낭유충이 검출되었다. 물달팽이로부터 검출한 피낭유충을 경구감염시킨 병아리, 오리, 흰쥐, 마우스 중 병아리와 오리에서 성충이 검출되었다. 물달팽이로부터 검출한 피낭유 충을 경구감염시킨 병아리에서의 충체 회수율은 평균 13. 1%이었다. 레디아는 주머니 모양으로 평균 $2.437{\;}{\times}{\;}0.317{\;}mm$ 크기이었으며 근육성의 인두와 체장의 약 112 부위까지 내려와 있는 맹장을 하나씩 갖고 있었다. 유미유충의 체부위는 방추형으로 평균 $0.262{\;}{\times}{\;}0.129{\;}mm$ 크기이었고, 꼬리부위는 긴 막대모양으로 평균 $0.528{\;}{\times}{\;}0.056{\;}mm$ $\times$ 크기이었다. 유미유충의 체부위에서는 45개의 두극이 배열되어 있는 두관과 미세한 과립을 다수 보유하고 있는 배설관이 특징적으로 관찰되었다. 피낭유충뜬 구형으로 평균 $0.144{\;}{\times}{\;}0.142{\;}mm$ 크기이었으며 2중의 낭벽을 가지고 있었다. 성충은 비교적 길쭉하였고 평균 $0.2760{\;}{\times}{\;}0.550{\;}mm$ 크기이었으며 두관에는 특징적인 45개의 두극이 배열되어 있었다. 이상의 결과로 우리 나라에서 물달팽이가 오리극구흡충의 제1 및 제2중간숙주로서 생활사 유지에 중요한 역할을 수행하고 있음을 확인하였다.

• 한국지반환경공학회 논문집
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• 제7권6호
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• pp.101-111
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• 2006

현장타설말뚝은 상부의 연약층을 관통하여 하부의 강한 암반층 상부에 거치시키는 경우, 말뚝은 선단지지말뚝으로 간주되며, 최소단면에서 말뚝에 발생하는 응력이나 실제 요구되는 설계기준에 따라서 작용하중은 결정된다. 연약하거나 풍화된 암반의 일정 깊이까지 현장타설말뚝을 설치하는 경우, 선단지지력과 주면저항력에 의해 지지력이 발현된다. 선단지지력 성분은 말뚝의 극한지지력에서 큰 비중을 차지한다. 그러나, 일반적으로 주면저항력은 선단지지력에 비해 훨씬 작은 말뚝 침하시 발현된다. 또한, 선단지지력은 근입부 바닥에 잔존하는 슬라임에 의해 영향을 받는다. 따라서, 근입부에 슬라임을 얼마나 잘 확인하는가와 시공법에 따라 선단지지력의 신뢰도는 결정되게 된다. 이것은 실제로 매우 어렵고 고가이며, 깊은 근입부에서는 더욱 심각하다. 따라서 이들 요소들로 인해서 작용하중하에서 말뚝의 거동은 주면저항력에 의해 지배되게 된다. 따라서 현장타설말뚝의 거동예측을 위한 연구는 주로 주면저항력 발현기구에 관심을 가지게 되는 것이다. 본 연구에서는 말뚝 두부에서의 하중 조건을 변화시켜가며 암반에 근입된 현장타설말뚝의 거동 차이를 분석하기 위하여 수치 해석을 수행하였다. 또한, 거칠기 요소의 모델링 유무에 따른 주면부 거동 특성도 조사하였다.

• 콘크리트학회논문집
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• 제14권3호
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• pp.430-439
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• 2002

콘크리트 내 이형철근 정착의 중요성은 철근콘크리트 구조에서 필수적인 요소이다. 표준갈고리는 인장정착을 위하여 광범위하게 사용되어 왔으나 콘크리트의 고강도화에 따라 부재 단면이 작아지는 추세 등으로 인하여 보-기둥 접합부에서는 좁은 공간에 철근이 과밀하게 배근됨으로써 시공 상의 어려움이 제기되고 있다. 단부 기계적 정착장치를 갖는 철근(단부보강철근)을 사용하는 경우 정착길이를 감소시키고, 정착부 상세를 단순화하며, 반복하중에 대한 저항능력을 증가시키는 등의 이점으로 인하여 공사비와 공사시간을 단축시킬 수 있을 것으로 사료된다. 본 연구는 단부보강철근의 뽐힘강도 및 거동에 대한 실험적 연구이다. D25 이형철근을 사용하여 수행된 총 33회의 뽑힘강도시험에서 실험변수는 철근 묻힘깊이, 철근중심과 콘크리트 가장자리간 거리, 단부보강 철물의 크기, 그리고 횡보강근(전단철근)의 간격이었다. 실험적으로 결정된 뽐힘강도는 CCD 방법에 의해 계산된 예측값에 관전하는 결과를 얻을 수 있었다. 철근 묻힘깊이가 증가하거나 철근과 콘크리트 가장자리간 거리가 증가할수록 뽑힘강도도 증가하였고 단부보강 철물의 크기가 증가함에 따라 뽑힘강도도 대체로 증가하는 경향을 보였다. 전단철근의 영향에 대한 연구로부터 뽑힘강도에 대한 파괴변에 걸친 전단철근의 영향을 나타내기 위하여 CCD 방법을 이용한 뽑힘강도 예측시 보정계수의 사용이 제안되었다.

• 헤리티지:역사와 과학
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• 제42권3호
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• pp.132-153
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• 2009

판단첨형식 연화문은 연꽃잎이 뾰족한 형태를 의미하는 것으로서 원형돌기식, 삼각돌기식, 판구곡절식 등과 더불어 백제의 대표적인 연화문 형식 중 하나이다. 이 연화문은 백제 한성기부터 사비기에 이르기까지 와당을 비롯한 불상 광배, 사리병, 두침 등에 다양하게 시문되었다. 그러나 현재 남아 있는 대부분의 판단첨형식 연화문은 사비기의 와당에 시문된 것이 대부분이다. 이들 연화문은 중국 북조나 남조, 고구려 등의 영향으로 제작된 것이 대부분이나 풍납토성 경당지구 출토와당, 용정리사지 출토 와당, 왕흥사지 출토 사리병 등에 시문된 연화문으로 볼 때 중국 북조의 영향이 절대적이었던 것으로 생각된다. 아울러 백제기에 나타난 여러 문양의 판단첨형식 연화문은 당시 백제의 활발한 문화교섭을 판단케 한다. 백제의 판단첨형식 연화문은 그 평면형태에 따라 보주형, 유엽형, 세장유엽형 등으로 구분할 수 있다. 보주형은 풍납토성 및 용정리사지에서 검출된 와당으로 그 시기는 한성기~웅진기의 것들이다. 반면, 유엽형 및 세장유엽형의 연화문은 무령왕릉 왕비두침, 은제탁잔, 서혈사지 와당, 구교리사지 와당, 하죽리 와당 등에서 확인되고 있어 웅진기 이후인 6세기 전반 이후의 연화문임을 추정케 한다. 현재 판단첨형 연화문 중 가장 이른 시기의 것은 풍납토성 경당지구에서 수습된 5세기 중반대의 것이다. 그러나 향후 점진적인 발굴조사를 통해 시기적으로 선행되는 와당이 수습될 가능성이 매우 높고 아울러 다른 다양한 형식도 출토될 여지가 적지 않다. 나아가 중국 남북조시기의 사지, 왕궁지, 기타 건물지의 발굴조사를 통해 다른 판단첨형식 연화문이 수습될 가능성도 적지 않다. 이는 그 동안 알려지지 않은 백제 판단첨형식 연화문의 계통을 파악하는 데에도 큰 도움이 될 수 있으리라 생각된다.

• 대한방사선기술학회지:방사선기술과학
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• 제45권4호
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• pp.299-304
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• 2022

This study uses the 'S-align' function to present a reference value of the X-ray tube angle for the realization of an image similar to that of the chest PA image during chest AP radiography. This study targeted dummy phantom and used a 17"×17" DR image receptor. The irradiation conditions were 110 kVp, 160 mA, 50 ms, and the distance between the central X-ray and the image receptor was set to 180 cm and 110 cm, respectively. The end of the catheter was placed at the 11th thoracic height to indicate the nasogastric tube. In the case of lung apex length measurement, the mean value of measurement was 30.53±0.47 in PA. T 0°, TCA 5~25°, TCE 5~15° were 21.07±0.29, 27.60±0.21, 34.13±0.44, 39.86±0.31, 45.96±0.61 mm, 54.13±0.37 mm, 16.16±0.46 mm, 9.81±0.35 mm, 2.75±0.30 mm, respectively. For the depth of the catheter end, the average value measured at PA was 6.70±0.31 mm. T 0°, TCA 5~25°, TCE 5~15° were 15.72±0.38 mm, 24.10±0.50 mm, 29.24±0.86 mm, 34.35±0.35 mm, 41.06±1.08 mm, 48.07±0.38 mm, 12.85±0.25 mm, 7.92±0.36 mm, 3.01±0.39 mm, respectively. The length of the lung apex was similar to that of chest PA when the angle of incidence was adjusted from 5° to 10° in the leg direction, and the depth of the catheter tip was most similar when the X-ray tube angle was incident at 10° in the head direction. Therefore, To change the X-ray tube angle according to the purpose of the examination during the chest AP radiography using 'S-align' function is considered necessary.

• 식물조직배양학회지
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• 제27권6호
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• pp.423-428
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• 2000

In 1997 when cloned sheep Dolly and soon after Polly were born, it had become head-line news because in the former the nucleus that gave rise to the lamb came from cells of six-year-old adult sheep and in the latter case a foreign gene was inserted into the donor nucleus to make the cloned sheep produce human protein, factor IX, in e milk. In the last few years, once the realm of science fiction, cloned mammals especially in livestock have become almost commonplace. What the press accounts often fail to convey, however, is that behind every success lie hundreds of failures. Many of the nuclear-transferred egg cells fail to undergo normal cell divisions. Even when an embryo does successfully implant in the womb, pregnancy often ends in miscarriage. A significant fraction of the animals that are born die shortly after birth and some of those that survived have serious developmental abnormalities. Efficiency remains at less than one % out of some hundred attempts to clone an animal. These facts show that something is fundamentally wrong and enormous hurdles must be overcome before cloning becomes practical. Cloning researchers now tent to put aside their effort to create live animals in order to probe the fundamental questions on cell biology including stem cells, the questions of whether the hereditary material in the nucleus of each cell remains intact throughout development, and how transferred nucleus is reprogrammed exactly like the zygotic nucleus. Stem cells are defined as those cells which can divide to produce a daughter cell like themselves (self-renewal) as well as a daughter cell that will give rise to specific differentiated cells (cell-differentiation). Multicellular organisms are formed from a single totipotent stem cell commonly called fertilized egg or zygote. As this cell and its progeny undergo cell divisions the potency of the stem cells in each tissue and organ become gradually restricted in the order of totipotent, pluripotent, and multipotent. The differentiation potential of multipotent stem cells in each tissue has been thought to be limited to cell lineages present in the organ from which they were derived. Recent studies, however, revealed that multipotent stem cells derived from adult tissues have much wider differentiation potential than was previously thought. These cells can differentiate into developmentally unrelated cell types, such as nerve stem cell into blood cells or muscle stem cell into brain cells. Neural stem cells isolated from the adult forebrain were recently shown to be capable of repopulating the hematopoietic system and produce blood cells in irradiated condition. In plants although the term$\boxDr$ stem cell$\boxUl$is not used, some cells in the second layer of tunica at the apical meristem of shoot, some nucellar cells surrounding the embryo sac, and initial cells of adventive buds are considered to be equivalent to the totipotent stem cells of mammals. The telomere ends of linear eukaryotic chromosomes cannot be replicated because the RNA primer at the end of a completed lagging strand cannot be replaced with DNA, causing 5' end gap. A chromosome would be shortened by the length of RNA primer with every cycle of DNA replication and cell division. Essential genes located near the ends of chromosomes would inevitably be deleted by end-shortening, thereby killing the descendants of the original cells. Telomeric DNA has an unusual sequence consisting of up to 1,000 or more tandem repeat of a simple sequence. For example, chromosome of mammal including human has the repeating telomeric sequence of TTAGGG and that of higher plant is TTTAGGG. This non-genic tandem repeat prevents the death of cell despite the continued shortening of chromosome length. In contrast with the somatic cells germ line cells have the mechanism to fill-up the 5' end gap of telomere, thus maintaining the original length of chromosome. Cem line cells exhibit active enzyme telomerase which functions to maintain the stable length of telomere. Some of the cloned animals are reported prematurely getting old. It has to be ascertained whether the multipotent stem cells in the tissues of adult mammals have the original telomeres or shortened telomeres.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1860-1871
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• 2011

Presently, The Regular Block System(Automatic, Interlocking block system) is usually used during the operation of block section. However, In case that the regular block system fails because of the failure of the fixed signals and block equipment or in case of the unexpected emergent situation which should drive on the single-track due to the accidents in the double-track section or the repair work of the one-track, the Substitute Block System to make use of the driving permission license(mapping ticket, mapping paper) is used. In case of the operation of the opposite line and the temporary one-track, the safety gets worse and the SBS may cause the fatal accidents such as a head-on & a rear-end collision. Also, the unmanned railroad stations has recently increased owing to the effective operation of the stations, for it is difficult to execute the SBS in their absence. As a result, the increase of the operation time made the train delayed. Being on the rise of these problems, in this study, we analyzed the problems and difficulties of the SBS on the single line which is lacking stability and safety and on the sections combined between maned and unmaned railroad stations. And we proposed the method to improve the existing drive permission license used for 50 years into the brand-new one with state-of-the art technology and scientific way. In the era of the 21th century, Carrying out the new SBS equipped with stability and safety, we will contribute to the effective operation of trains and the satisfaction of our customers in the future.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.545-555
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• 2011

Presently, The Regular Block System(Automatic, Interlocking block system) is usually used during the operation of block section. However, In case that the regular block system fails because of the failure of the fixed signals and block equipment or in case of the unexpected emergency which should drive on the single line due to the accidents in the double line section or the repair work of the single line, the Substitute Block System to use the driving permission license(mapping ticket and paper) is used. In case of the operation of the opposite line and the temporary one line, the safety gets worse and the SBS may cause the fatal accidents such as a head-on & a rear-end collision. Also, the unmanned railroad stations has recently increased owing to the effective operation of the stations, for it is difficult to execute the SBS in their absence. As a result, the increase of the operation time made the train delayed. Being on the rise of these problems, in this study, we analyzed the problems and difficulties of the SBS on one line which is lacking stability and safety and on the sections combined between maned and unmaned railroad stations. And we proposed the suitable method in KORAIL referring to the examples of European & Japan railways lately. According to the passing of the high tech time, If the new SBS equipped with stability and safety is executed, it will contribute to the effective operation of trains and the satisfaction of KORAIL customers in the future.

• Asian-Australasian Journal of Animal Sciences
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• 제24권12호
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• pp.1729-1735
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• 2011

The effect of flaxseed meal on broiler performance, carcass characteristics, alpha-linolenic acid contents, and organoleptic characteristics of chicken meat was studied during a 42 day experiment. Broiler chicks were randomly allotted to 4 experimental groups and fed iso-energetic and iso-nitrogenous diets containing flaxseed meal at 0, 5, 10 and 15%. Flaxseed meal did not affect the weekly body weight of broiler chicks during the first two weeks but thereafter weekly body weight reduced among flaxseed meal groups. At the end of $6^{th}$ week, birds fed on 15% flaxseed meal showed a reduction of 8% in body weight compared to the control group. Control group had significantly higher weight gain with slightly higher feed consumption and better feed conversion ratio (FCR), protein efficiency ratio (PER), and energy efficiency ratio (EER) than the flaxseed meal groups. Among the treatments, birds of 5 and 10% flaxseed meal groups had significantly better FCR, PER and EER compared to those of the 15% flaxseed meal group. The carcass characteristics data indicated a significant reduction in the eviscerated weight and breast yield at 15% flaxseed meal in the diet as compared to other dietary groups. However, the alpha-linolenic acid content in both breast and thigh meat was higher with an increasing level of flaxseed meal in the diets without affecting the sensory acceptability of meat. Based on the present study, up to 10% of flaxseed meal may be used in broiler diet to enhance the alpha-linolenic acid content in the broiler meat.