• 한국해양환경ㆍ에너지학회지
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• 제16권4호
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• pp.239-247
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• 2013

최근 화석연료의 고갈과 환경오염으로 인하여 해상풍력에너지와 같은 신재생 에너지에 대한 관심이 높아지고 있다. 본 연구에서는 범용 동역학해석 프로그램인 MSC.ADAMS를 이용하여 공력하중 및 전기 발전기 토오크를 결정하기 위한 테브난(Thevenin) 방정식이 고려된 해상풍력발전기의 다물체 동역학 해석 기법을 검토하였다. 해석대상으로 고려한 시스템은 5MW급 해상풍력발전기이며, 3개의 블레이드가 수평축 방향에서 역풍을 받아 전기를 생산하는 수평축 풍력발전 형태이다. 블레이드에 작용하는 공력하중은 블레이드 요소 모멘텀 이론을 기반으로 일반화된 동적 웨이크를 고려할 수 있도록 개발된 AeroDyn 프로그램으로부터 산출하였다. 해상풍력발전기의 주요 연결부에서의 동적하중과 토오크 특성이 실제 현상과 유사하게 산출될 수 있도록 하기 위하여, 다물체 동역학 모델 상에 블레이드와 타워는 실제 구조 특성치를 고려한 유연체 모델링을 적용하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제21권6호
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• pp.807-817
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• 2008

Steers with ad libitum access to rice straw were assigned to four diets to evaluate the effects of maize or soybean hull supplementation on intake, in vivo digestibility, ruminal pH, VFA, ammonia-nitrogen ($NH_3-N$) and in situ ruminal disappearance of feed nutrients by cattle consuming rice straw. Supplement treatments were: no supplement (RS); soybean meal at 0.127% BW (SBM); cracked maize at 0.415% BW plus 0.044% BW soybean meal (MAIZE); or soybean hulls at 0.415% BW plus 0.044% BW soybean meal (HULLS). The MAIZE and HULLS diets were formulated to provide approximately 4 MJ of $NE_m$ per kg of diet. Rice straw DMI was not affected (p = 0.34) by supplement. Apparent dry matter (DM) digestibility was greater (p<0.001) for MAIZE and HULLS (56.6 and 60.0%, respectively) than for steers consuming SBM or RS (51.8 and 44.4%, respectively). Apparent NDF digestibility was greater (p<0.0004) for HULLS than MAIZE (61.7 vs. 58.0%, respectively) and apparent ADF digestibility was greater (p<0.0008) for HULLS than MAIZE (61.1 vs. 49.2%, respectively). There was no difference in apparent hemicellulose digestibility (p = 0.43). Analysis of ruminal fluid collected 0, 2, 4, 6, and 8 h post-feeding revealed ammonia-nitrogen was greatest (p<0.05) for steers on SBM and HULLS diets at 2 h (24.08 and 22.57 mg/dl, respectively) and total volatile fatty acids was greatest (p<0.05) for HULLS at 4 h (230 mM/L). In situ disappearance, measured at 0, 2, 4, 6, 8, 16 and 24 h, indicated that SBM, MAIZE and HULLS tended to enhance the digestibility of DM and fiber components of rice straw. In situ disappearance of rice straw DM was greatest for SBM and/or HULLS from 4 to 24 h (p = 0.03). Rice straw NDF and ADF disappearance was enhanced by supplementation from 16 to 24 h (p<0.02). Rice straw DM, NDF and ADF disappearances at 24 h were similar for MAIZE and HULLS treatments. When feeding cattle rice straw diets, energy and protein-based supplements are essential. This study showed that fiber-based supplements are just as, if not more, effective as starch-based supplements in rice straw utilization. This study shows that soybean hulls, in spite of their high fiber content, are as efficient as maize for supplementing rice straw primarily because fiber in soybean hulls is highly digestible as shown by in vivo digestibility and in situ disappearance.

• Asian-Australasian Journal of Animal Sciences
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• 제30권11호
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• pp.1529-1539
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• 2017

Objective: The objective of this study was to compare the DNA methylation profile in the longissimus dorsi muscle between Small Tailed Han and Dorper${\times}$Small Tailed Han crossbred sheep which were known to exhibit significant difference in meat-production. Methods: Six samples (three in each group) were subjected to the methylated DNA immunoprecipitation sequencing (MeDIP-seq) and subsequent bioinformatics analyses to detect differentially methylated regions (DMRs) between the two groups. Results: 23.08 Gb clean data from six samples were generated and 808 DMRs were identified in gene body or their neighboring up/downstream regions. Compared with Small Tailed Han sheep, we observed a tendency toward a global loss of DNA methylation in these DMRs in the crossbred group. Gene ontology enrichment analysis found several gene sets which were hypomethylated in gene-body region, including nucleoside binding, motor activity, phospholipid binding and cell junction. Numerous genes were found to be differentially methylated between the two groups with several genes significantly differentially methylated, including transforming growth factor beta 3 (TGFB3), acyl-CoA synthetase long chain family member 1 (ACSL1), ryanodine receptor 1 (RYR1), acyl-CoA oxidase 2 (ACOX2), peroxisome proliferator activated receptor-gamma2 (PPARG2), netrin 1 (NTN1), ras and rab interactor 2 (RIN2), microtubule associated protein RP/EB family member 1 (MAPRE1), ADAM metallopeptidase with thrombospondin type 1 motif 2 (ADAMTS2), myomesin 1 (MYOM1), zinc finger, DHHC type containing 13 (ZDHHC13), and SH3 and PX domains 2B (SH3PXD2B). The real-time quantitative polymerase chain reaction validation showed that the 12 genes are differentially expressed between the two groups. Conclusion: In the current study, a tendency to a global loss of DNA methylation in these DMRs in the crossbred group was found. Twelve genes, TGFB3, ACSL1, RYR1, ACOX2, PPARG2, NTN1, RIN2, MAPRE1, ADAMTS2, MYOM1, ZDHHC13, and SH3PXD2B, were found to be differentially methylated between the two groups by gene ontology enrichment analysis. There are differences in the expression of 12 genes, of which ACSL1, RIN2, and ADAMTS2 have a negative correlation with methylation levels and the data suggest that DNA methylation levels in DMRs of the 3 genes may have an influence on the expression. These results will serve as a valuable resource for DNA methylation investigations on screening candidate genes which might be related to meat production in sheep.

• ALGAE
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• 제24권1호
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• pp.1-29
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• 2009

A synthesis of early exploration and the discovery of marine algae in the upper North Pacific and Bering Sea is presented covering the period from the late 1730s to around 1900. Information is provided about these early efforts to gather natural objects, including seaweeds, and names of these algae are enumerated. The first collections of marine algae in this broad region were those made by steller and Kracheninnkov from the Kamchatka Peninsula,Russia,during the Second Kamchatkan Expedition (1735-1742) and were described by Gmelin (1768). The first known algal collections in Alaska were those made byMerck in his 1790-1791 visits to Unalaska Island during the Billings expedition (1785-1794). British-sponsored expeditions for commercial purposes and for exploration and dis-covery allowed surgeon-naturallist Archibald Menzies to garher seaweeds that Dawson Turner and others worked up back in Europe. Several of the Russian Expeditions during the first half of the 18'!' century had naturalists aboard. the first Russian circumnavigation of the globe (1803-1806), with the ships 'Nadeshda' and 'Neva,' under the com-mand of Capt. Adam von Krusenstern had naturalists Langsdorff, Tilesius, and Horner, all of whom collected sea-weeds. The naturalist Adelbert Chanmisso accompanied the Romanzof Expedition (1815-1818) on the Russian vessel 'Rurik' under the command of Otto von Kotzebue and made collections of algae in the Aleutians as well as in the Kurils and Kamchatka. The Lutke expedition of 1826-1829 consisted of thw ships. Feodor Lutke was in command of the 'Seniavin' with K.H. Mertens aboard as physician-naturalist, and the 'Moller' was under the command of staniukovich accompanied by the naturalist G. Kastalsky. The first American-sponsored scientific expedition (1838-1842) was that commanded by Charles Wilkes, and the algae that were collected were worked up by J.W. Bailey and W.H. Harvey. The Russian naturalist Ilya Voznesenskii spent the period 1839-1849 in Russian Americ (Alaska and northern California) energetically traveling and making numerous collections of natural objects as well as ethno-graphic artefact. His algae were described by F.j. Ruprecht back in St. petersbung. The Swedish scientific vessel, the'Vega' (1878-1880), was under the command of Nordenskiold. The naturalist F.R. Kjellman made algal collections from Port Clarence, Alaska, as well as from bering Island and St. Lawrence Island in the Bering sea. The Harriman Alaskan Expedition in the summer of 1899, with the ship 'George W. Elder,' was sponsored by railroad magnate E.H. Harriman of New York City and had several scientific personnel aborad, including the phycologist De Alton Saunders. Algae were collected in Alaska and Washington. During the same summer of 1899 a scientific expedition organized by the University of California and including W.L. Jepson, L.E. Hunt, A.A Lawson, and W.A. Setchell as participants also visited Alaska and made collections of alage from various locations.

• 에너지공학
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• 제21권3호
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• pp.254-264
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• 2012

원자력발전소 중대사고시 노심용융물의 Rayleigh-Benard 자연대류 문제에 대한 예비실험으로 두 평판 사이의 거리, 측면벽의 유무 및 평판의 기하구조가 열전달에 미치는 영향에 대해 실험적 연구를 수행하였다. 열전달 실험을 대신하여 상사성의 원리를 이용한 황산-황산구리 수용액의 전기도금계를 물질전달계로 채택하였다. 실험은 $Ra_s$는 $1.06{\times}10^7{\sim}2.91{\times}10^{10}$의 범위에서 실험적 조건을 변화시켜가며 열전달을 측정하였다. 실험결과 단일 수평평판에서 측정한 열전달은 McAdams의 수평평판 자연대류 열전달 상관식과 일치하였고 두 평판에서 측정한 열전달은 Dropkin과 Somerscales, Globe와 Dropkin의 Rayleigh-Benard 자연대류 열전달 상관식과 매우 유사한 경향을 보였다. 두 평판 사이의 거리가 작을 경우 열전달이 높다가 거리가 증가하면 단일 수평평판에서의 자연대류 열전달과 같아졌다. 평판에 설치된 휜(Fin)은 열전달을 향상시켰다. 모든 경우에서 측면벽이 없는 경우의 열전달이 측면 벽이 있는 경우보다 항상 높았다.

• 대한기계학회논문집A
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• 제41권7호
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• pp.599-605
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• 2017

무인 자율 주행 차량이 야지 환경에서 안전하게 주행하기 위해서는 차량의 주행 안정성이 반드시 고려되어야 한다. 본 논문에서는 실시간 주행 안정성 분석을 위한 자율 주행 시뮬레이션에 적용되는 경로 추종 제어기를 제시한다. 경로 추종 제어기는 Preview 거리를 사용하여 차량의 지향 각을 제어하고, 요 모멘트 관측기로부터 추정된 외란 모멘트를 보상하여 지향 각 오차와 횡 방향 거리 오차를 감소시킨다. 곡선 경로에서는 곡률을 이용하여 차량의 주행 속도를 결정한다. 대상 차량은 6X6 스키드 조향 차량이기 때문에 6개의 휠에 서로 다른 구동력을 분배하는 방법을 사용하여 주어진 경로를 주행한다. ADAMS에서 모델링 된 차량을 MATLAB과 연동시켜 시뮬레이션하고, 경로 추종 제어기 성능을 검증하였다.

• 천문학논총
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• 제32권2호
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• pp.367-380
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• 2017

The life and astronomical activity of Lee Deok-Seong (李德星, 1720-1794) was studied using various historical sources, including the astronomical almanac, Seungjeongwon-Ilgi (Daily records of Royal Secretariat of Joseon dynasty), and the Gwansang-Gam's logbooks during Joseon dynasty (A.D. 1392-1910). We present the results of the study including the following main findings. First, from the investigation of Lee's family tree, we find that a number of his relatives were also astronomers, notably Samryeok-Gwan (三曆官, the post of calendrical calculation). Second, we find that he took part in the compilation of an annual astronomical almanac over a period of at least 16 years. His major achievements in the astronomy of the Joseon dynasty were to establish a new method of calendar-making calculation and to bring astronomical materials to the Joseon court through a visit to China. The Joseon dynasty enforced the Shixianli (時憲曆, a Chinese calendar made by Adam Shall) in 1654 without fully understanding the calendar. So an astronomer and an envoy were dispatched to China in order to master the intricacies of the calendar and to learn as much of Western science as was available in that time and place. Lee Deok-Seong worked at the Gwansang-Gam (觀象監, Royal Astronomical Bureau) during the reigns of King Yeongjo (英祖) and Jeongjo (正祖). As best as we can ascertain in relation with the calculations in the Shixian calendar, Lee visited China four times. During his trips and interactions, he learned a new method for calendar-making calculations, and introduced many Western-Chinese astronomical books to Joseon academia. Lee greatly improved the accuracy of calendrical calculations, even while simplifying the calculation process. With these achievements, he finally was promoted to the title of Sungrok-Daebu (崇祿大夫), the third highest grade of royal official. In conclusion, history demonstrates that Lee Deok-Seong was one of the most outstanding astronomers in the late-Joseon dynasty.

• 디지털융복합연구
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• 제17권12호
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• pp.467-472
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• 2019

국내 스마트폰 이용률이 증가함에 따라 모바일 게임의 발전 속도도 빨라지고 있지만, 시장 규모가 커짐에 따라 경쟁이 심화되는 현상이 나타나고 있다. 이러한 모바일 게임 시장에서 게임을 성공시키기 위한 요소 중 하나로 UI를 제시하고 있는데, 이러한 모바일 게임 UI 설계 시 이전에 기능과 심미적 표현, 기능중심디자인과 정보 전달과 더불어 사용자의 경험을 설계하는 측면에서 접근되어야 한다는 주장이 제시되었다. 본 논문에서는 UX요소 중 경험을 이용해 효과적인 모바일 RPG의 로비 layout을 제시하였다. Ernest Adams와 Andrew Rollings의 레이아웃 분류 방법을 통해 google play 누적매출 순위 20위 내 모바일 RPG의 9개를 선정해 로비 layout을 분석한 결과 모바일 RPG장르의 첫 시장 흥행을 이끌었던 게임의 로비 layout이 이후 출시되어 흥행한 게임의 기준이 되었다는 결과가 나왔다. 이는 기존 RPG를 이용했던 경험에 의해 낮은 진입장벽과 학습이 불필요 하다는 점에서 이용자가 이전에 이용하였던 게임과 유사하게 느끼는 로비 layout이 효과적이라고 해석할 수 있다. 향후 연구에서는 RPG 이외의 다른 장르에 관한 최적의 UX를 측정할 수 있는 연구가 진행된다면 넓은 장르의 공통적인 layout을 도출해낼 수 있을 것이다.

• 국제초고층학회논문집
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• 제10권4호
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• pp.345-364
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• 2021

Developments in the understanding of fire behaviour for large open-plan spaces typical of tall buildings have been greatly outpaced by the rate at which these buildings are being constructed and their characteristics changed. Numerous high-profile fire-induced failures have highlighted the inadequacy of existing tools and standards for fire engineering when applied to highly-optimised modern tall buildings. With the continued increase in height and complexity of tall buildings, the risk to the occupants from fire-induced structural collapse increases, thus understanding the performance of complex structural systems under fire exposure is imperative. Therefore, an accurate representation of the design fire for open-plan compartments is required for the purposes of design. This will allow for knowledge-driven, quantifiable factors of safety to be used in the design of highly optimised modern tall buildings. In this paper, we review the state-of-the-art experimental research on large open-plan compartment fires from the past three decades. We have assimilated results collected from 37 large-scale compartment fire experiments of the open-plan type conducted from 1993 to 2019, covering a range of compartment and fuel characteristics. Spatial and temporal distributions of the heat fluxes imposed on compartment ceilings are estimated from the data. The complexity of the compartment fire dynamics is highlighted by the large differences in the data collected, which currently complicates the development of engineering tools based on physical models. Despite the large variability, this analysis shows that the orders of magnitude of the thermal exposure are defined by the ratio of flame spread and burnout front velocities (V_S / V_BO), which enables the grouping of open-plan compartment fires into three distinct modes of fire spread. Each mode is found to exhibit a characteristic order of magnitude and temporal distribution of thermal exposure. The results show that the magnitude of the thermal exposure for each mode are not consistent with existing performance-based design models, nevertheless, our analysis offers a new pathway for defining thermal exposure from realistic fire scenarios in large open-plan compartments.

• 대순사상논총
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• 제34집
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• pp.323-351
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• 2020

此论文的目的是通过横向比较 《圣经》 和 《典经》 中的道成肉身思想, 揭示基督教最终走向神本主义道路, 大巡真理会最终走向人文主义道路的根本原因。基督教和大巡真理会都承认人的世界之上另有一个人的感官触及不到的世界。而且他们都主张上面的世界有一个至高者, 而且这位至高者通过女人的身体来到了人的世界。但不同的是, 基督教认为2000多年前在伯利恒出生的耶稣就是那位至高者, 而大巡真理会认为100多年前出生在朝鲜客望里的姜一淳才是那位至高者。基督教的神来到人间是为了替人类赎罪, 为此道成肉身者被钉在了十字架上流干了血, 成了赎罪的羔羊。大巡真理会的上帝降诞人间是为了帮人类解冤, 为此道成肉身者大巡天地人三界, 探索偏斜的度数并将其调正。基督教所谓的"罪"本质上是对至高神的"背叛", 这意味着神的世界不能容忍罪, 所以当第一个人 (亚当) 背叛神以后被赶出了圣洁的伊甸园。从此人的世界与神的世界之间就产生了不能逾越的鸿沟。相反, 大巡真理会所谓"偏斜的度数"并非是对至高者的背叛, 而只是一种自然的结果而已。也就是说, 度数偏斜的现象不仅能发生在人的世界里, 也能发生在神明的世界之中, 而且两个世界还可以相互作用, 相互影响。因此可以说, 基督教思想中的两个世界是两个完全不同秩序和不同系统的世界, 而大巡真理会思想中的两个世界是同一个秩序和同一个系统下运转的世界。大多数将某一事物分割成两个部分的思想主要是为了强调一边比另一边更重要或更关键。基督教以神的世界为人世界的最终根源和终极关怀, 以人对神的绝对信仰和绝对崇拜为人生最高的价值。相反大巡真理会则认为人的世界决定了神明界的存在意义, 主张人与人之间, 人与自然之间的互利相生是人尊时代的核心价值。由此可以得出本论文的最终结论 : 导致基督教踏上神本主义道路的根本原因是他们相信在完全相隔绝的两个世界中, 神的世界是人世界的最终根源和终极关怀 ; 导致大巡真理会走向人文主义的根本原因是他们相信在可以相互作用且可以相互影响的神明界与人世界中, 人世界决定神明界的存在意义。