• 제목/요약/키워드: DO-178

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홍수터에서 수치해석과 수리실험을 통한 이차류 및 수리특성에 관한 연구 (A Study on the Secondary Flow and Hydraulic Characteristics Using 3D model and Experiment in Flood Plane)

  • 정동규;박용성;송창근;김영도
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2015년도 학술발표회
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    • pp.178-178
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    • 2015
  • 본 연구는 복단면구조의 수로에서 이차류 및 흐름특성을 비교, 관측하는 것이며 이러한 흐름특성을 연구하기 위해 폭 1.2 m, 길이 14 m, 높이 0.6 m인 실험수로를 이용하여 수심비 0.25 및 0.40 조건에서 0.05, 0.10 CMS의 유량으로 총 4가지 조건으로 실험을 진행하였고 이를 비교하기 위해 3차원 수치해석모형인 FLOW-3D를 이용하여 수치해석결과와 수리실험결과를 비교하였다. 주수로 및 홍수터의 수심과 유량의 조건이 각각 다른 4가지 조건 별 변화를 수리실험과 수치해석을 통해 분석한 결과, Shino & Knight(1991)에서의 언급한 내용과 부분적으로는 동일한 결과를 보였으나, 수치해석 부분에서의 결과와는 차이를 보였다. 일반적으로 복단면구조에서 발생하는 이차류는 수위 및 수심별 유속의 차이에서 발생하는 연직방향의 유속의 영향과 복단면과 주수로의 구조적 차이에서 발생하는 횡방향 유속의 영향과 같은 복합적인 작용으로인해 발생하게 되지만 수치해석의 결과에서는 수위차이에 의한 연직방향의 유속이 횡방향 유속보다 지배적인 결과를 보여 본 연구 중 고유속의 조건에서는 이차류의 형성이 수리실험 및 기존 연구결과들과 차이를 보였다.

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선형 및 일반형 침투깊이를 이용한 6자유도 햅틱 렌더링 알고리즘 (Six-degree-of-freedom Haptic Rendering using Translational and Generalized Penetration Depth Computation)

  • ;이영은;김영준
    • 로봇학회논문지
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    • 제8권3호
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    • pp.173-178
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    • 2013
  • We present six-degree-of-freedom (6DoF) haptic rendering algorithms using translational ($PD_t$) and generalized penetration depth ($PD_g$). Our rendering algorithm can handle any type of object/object haptic interaction using penalty-based response and makes no assumption about the underlying geometry and topology. Moreover, our rendering algorithm can effectively deal with multiple contacts. Our penetration depth algorithms for $PD_t$ and $PD_g$ are based on a contact-space projection technique combined with iterative, local optimization on the contact-space. We circumvent the local minima problem, imposed by the local optimization, using motion coherence present in the haptic simulation. Our experimental results show that our methods can produce high-fidelity force feedback for general polygonal models consisting of tens of thousands of triangles at near-haptic rates, and are successfully integrated into an off-the-shelf 6DoF haptic device. We also discuss the benefits of using different formulations of penetration depth in the context of 6DoF haptics.

Association between Single Nucleotide Polymorphisms in the Dgat2 Gene and Beef Carcass and Quality Traits in Commercial Feedlot Steers

  • Li, J.;Xu, X.;Zhang, Q.;Wang, X.;Deng, G.;Fang, X.;Gao, X.;Ren, H.;Xu, S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제22권7호
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    • pp.943-954
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    • 2009
  • Diacylglycerol acyltransferase (DGAT) is a key enzyme that catalyzes the final and rate-limiting step of triglyceride synthesis. Both DGAT1 and DGAT2 genes code proteins with DGAT activity. Studies have shown DGAT1 polymorphisms associate with intramuscular fat deposition in beef cattle, but fewer associations between DGAT2 and beef cattle economic traits have been reported. The objective of this study was to investigate single nucleotide polymorphism (SNP) in intron3 of bovine DGAT2 and evaluate the associations of that with carcass, meat quality, and fat yield traits. Test animals were 157 commercial feedlot steers belonging to 3 Chinese native breeds (22 for Luxi, 24 for Jinnan, and 23 for Qinchuan), 3 cross populations (20 for Charolais${\times}$Fuzhou, 18 for Limousin ${\times}$Luxi, and 17 for Simmental${\times}$Jinan) and 1 Taurus pure breed population (16 Angus steers). In the current study, 15 SNP were discovered in intron3 and exon4 of DGAT2 at positions 65, 128, 178, 210, 241, 255, 270, 312, 328, 334, 365, 366, 371, 415, and 437 (named as their positions in PCR amplified fragments). Only 7 of them (128, 178, 241, 270, 312, 328, and 371) were analyzed, because SNP in three groups (65-128-255, 178-210-365 and 241-334-366) were in complete linkage disequilibrium within the group, and SNP 415 was a deletion and 437 was a null mutation. Frequencies for rare alleles in the 3 native breed populations were higher than in the 3 cross populations for 178 (p = 0.04), 270 (p = 0.001), 312 (p = 0.03) and 371 (p = 0.002). A general linear model was used to evaluate the associations between either SNP genotypes or allele substitutions and the measured traits. Results showed that SNP 270 had a significant association with the fat yield associated with kidney, pelvic cavity, heart, intestine, and stomach (KPHISY). Animals with genotype CC and CT for 270 had less (CC: -7.71${\pm}$3.3 kg and CT: -5.34${\pm}$2.5 kg) KPHISY than animals with genotype TT (p = 0.02). Allele C for 270 was associated with an increase of -4.26${\pm}$1.52 kg KPHISY (p = 0.006) and $-0.92{\pm}0.45%$ of retail cuts weight percentage (NMP, Retail cuts weight/slaughter body weight) (p = 0.045); allele G for 312 was associated with an increase of -5.45${\pm}$2.41 kg KPHISY (p = 0.026). An initial conclusion was that associations do exist between DGAT2 gene and carcass fat traits. Because of the small sample size of this study, it is proposed that further effort is required to validate these findings in larger populations.

Clitoria ternatea L. as a Potential High Quality Forage Legume

  • Abreu, Matheus Lima Correa;Vieira, Ricardo Augusto Mendonca;Rocha, Norberto Silva;Araujo, Raphael Pavesi;Gloria, Leonardo Siqueira;Fernandes, Alberto Magno;Lacerda, Paulo Drude De;Junior, Antonio Gesualdi
    • Asian-Australasian Journal of Animal Sciences
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    • 제27권2호
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    • pp.169-178
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    • 2014
  • Samples of Clitoria ternatea L. (Cunh$\tilde{a}$) were harvested at 35, 50, 70, and 90 d after a uniformity harvest in a field study designed as a completely randomized design with a total of 18 experimental plots. The dry matter yield of the whole plant was separated quantitatively into leaves, stems, and pods at each harvesting age. Chemical analyses and in vitro gas production kinetics were performed to assess the quality of the plant parts. Yields, chemical composition, and estimates of gas production parameters were analyzed by fitting a mixed statistical model with two types of covariance structures as follows: variance components and an unrestricted structure with heterogeneous variances. Fast and slow gas yielding pools were detected for both leaves and stems, but only a single pool was detected for pods. The homoscedasticity assumption was more likely for all variables, except for some parameters of the gas production kinetics of leaves and stems. There was no presence of typical pods at 35 and 50 d. In the leaves, the fibrous fractions were affected, whereas the non-fibrous fractions were unaffected by the harvesting age. The harvesting age affected the majority of the chemical constituents and gas kinetic parameters related to the stems. The leaves of this legume were the least affected part by the aging process.

느타리버섯 품종 '흑타리'와 '미소'의 초위성체 특성구명 (Characterization of simple sequence repeats in the Pleurotus ostreatus cultivars, 'Heuktari' and 'Miso')

  • 박보경;하병석;김민근;이병주;최종인;류재산
    • 한국버섯학회지
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    • 제14권4호
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    • pp.174-178
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    • 2016
  • SSR은 병렬적으로 반복되는 작은 DNA서열을 말하며, 다양한 마커 기반 연구에 활용되고 있다. 국내의 주요 느타리품종인 '흑타리'와 '미소'의 유전체를 Pacbio를 이용하여 해독하였고 이 서열 정보에서 생물정보학을 이용하여 SSR을 분리하여 특성구명을 하였다. '흑타리'와 '미소' 유래 단핵균사의 유전체의 크기는 각각 40.8 Mbp와 40.3 Mbp로 밝혀졌고, 이는 사철느타리의 단핵균사 PC9과 PC15보다 컸으나, 큰느타리보다는 작았다. 총 949개와 968개의 SSR이 '흑타리'와 '미소'의 유전체 분석을 통하여 각각 검출되었다. 5개의 느타리류 유전체의 SSR 분포와 특징을 비교분석한 결과 흑타리와 미소의 SSR 갯수가 가장 많았으며, 이들의 반복서열의 분포는 다른 느타리류와 비슷한 경향을 보였다. 3-mers, 6-mers와 8-mers가 가장 발견빈도가 높은 패턴이었다.

전남 신안군 압해도의 나방상 (A Faunistic Study of Moths (Insecta, Lepidoptera) on Is. Aphae-do, Sinan-gun, Jeollanam-do, Korea)

  • 임진택;김석이;김병운;최세웅
    • 환경생물
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    • 제25권2호
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    • pp.178-189
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    • 2007
  • 도시화에 따른 도서지방의 생태계 변화를 규명하기 위한 기초 자료를 확보하기 위하여 전남 신안군 압해도 일대에 서식 분포하고 있는 나비목 곤충을 대상으로 2006년 3월부터 9월까지 13회 나방을 채집 확인하였다. 본 조사 결과 동정, 확인된 나비목 곤충은 총 16과 241속 339종이었다. 채집된 종중 밤나방과가 129종으로 가장 많았고, 다음으로 자나방과(81종), 명나방과(38종) 순이었으며, 개체수로는 자나방과, 밤나방과, 명나방과, 갈고리나방과의 순이었다. 조사기간 동안 단 1회만 채집된 종은 가을뒷노랑밤나방 등 201종(59.2%)으로 조사되었으며 이중 단지 한 개체만 채집된 종은 99종(29.2%)이었다. 본 연구는 도시화에 따른 생태계 교란이 우려되는 압해도 일원을 대상으로 생태계 변화에 대한 기초 자료로 이용할 수 있을 것이다.

선택적 볼륨분해를 이용한 정적 CAD 모델의 함몰특징형상 수정 (Editing Depression Features in Static CAD Models Using Selective Volume Decomposition)

  • 우윤환;강상욱
    • 한국CDE학회논문집
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    • 제16권3호
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    • pp.178-186
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    • 2011
  • Static CAD models are the CAD models that do not have feature information and modeling history. These static models are generated by translating CAD models in a specific CAD system into neutral formats such as STEP and IGES. When a CAD model is translated into a neutral format, its precious feature information such as feature parameters and modeling history is lost. Once the feature information is lost, the advantage of feature based modeling is not valid any longer, and modification for the model is purely dependent on geometric and topological manipulations. However, the capabilities of the existing methods to modify static CAD models are limited, Direct modification methods such as tweaking can only handle the modifications that do not involve topological changes. There was also an approach to modify static CAD model by using volume decomposition. However, this approach was also limited to modifications of protrusion features. To address this problem, we extend the volume decomposition approach to handle not only protrusion features but also depression features in a static CAD model. This method first generates the model that contains the volume of depression feature using the bounding box of a static CAD model. The difference between the model and the bounding box is selectively decomposed into so called the feature volume and the base volume. A modification of depression feature is achieved by manipulating the feature volume of the static CAD model.

양식 참전복(Haliotis discus hannai)의 비병증 예의 근육변성 (Myopathy in Clinically Healthy Cultured Abalone Haliotis discus hannai)

  • 김보성;이성주;황세명;이무근;박영진;송교정;허민도
    • 한국수산과학회지
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    • 제47권2호
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    • pp.174-178
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    • 2014
  • In this study, 6-10 clinically healthy farmed abalone, Haliotis discus hannai were obtained from Jeollanam-Do Wando Soan-myeon, Bogil-myeon, and Nohwa-eup monthly for 1 year 7 months and were examined histopathologically. As a result, the adductor muscle had severe cellular swelling and myonecrosis. These lesions were stained with hematoxylin and eosin and Giemsa. The lesions were not caused by infection of bacteria or parasites. We investigated the relationship between lesion frequency and water temperature and discovered that increased water temperature was associated with increasing lesion frequency. As water temperature is related to growth rate, increased growth rate was closely related to increased lesion frequency. We considered that these lesions could be a useful factor in measuring shellfish health.

Taxonomic Study of Poorly-known Marine Pleurostomatid Ciliates of Litonotus paracygnus and L. pictus (Ciliophora: Pleurostomatida) from Korea

  • Kim, Se-Joo;Min, Gi-Sik
    • Animal Systematics, Evolution and Diversity
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    • 제25권2호
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    • pp.167-178
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    • 2009
  • Two poorly known and often confused pleurostomatid ciliates, Litonotus paracygnus Song, 1994 and L. pictus Gruber, 1884, were collected from the coastal waters of Yeonggeumjeong and Bongpo-port, Gangwondo in the East Sea and from the Iwon tide embankment near Ganwol-do, Chungcheongnam-do in the Yellow Sea, Korea. These species were described based on live observations, the protargol-impregnation and morphometrics of the species. Also provided are their diagnoses. The small subunit ribosomal DNA (SSU rDNA) sequences of these species were compared with previously known sequences of related species. The diagnostics of the two Litonotus species are as follows. L. paracygnus: 150-300 $\mu$m long in vivo, strongly contractile neck region, two ellipsoid macronuclei (Ma) and one micronucleus (Mi), 7 left (LSK) and 11-14 right somatic kineties (RSK), 2-4 contractile vacuoles (CV) located on the posterior end, extrusemes (Ex) distributed on the anterior region of the ventral margin only. L. pictus: about 200-600 $\mu$m long in vivo, extremely contractile, beautiful body color with rows of yellow to yellow-brownish cortical pigment granules, 12-21 Ma arranged in moniliform pattern, infrequently vermiform, 7-11 LSK and 18-26 RSK, several CV located on both margins, Ex distributed on the anterior region of the ventral margin only. In this study, this genus was firstly recorded in Korea.

임상실습을 경험한 응급구조학과 학생들의 진로정체감, 진로결정수준 및 진로준비행동의 관계 (Relationship between career identity, career decision level and career preparation behavior of paramedic students after clinical practice)

  • 최미영;강민주;주정미
    • 한국응급구조학회지
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    • 제28권2호
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    • pp.63-75
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    • 2024
  • Purpose: This study investigated career identity, decision-making, and preparation behaviors among emergency medical service (EMS) students after clinical practice, aiming to enhance their career guidance by identifying influential factors. Methods: This study targeted 178 students enrolled in the Department of Paramedicine in K-do, G-do, and D metropolitan cities. Data were collected between March 14th and April 30, 2024. The collected data were analyzed using SPSS 25.0, employing techniques such as frequency, correlation, and multiple regression analyses. Results: The findings indicated that components of career identity, encompassing affective and cognitive aspects, exerted significant effects on career decision levels (career assurance and career indecision) (p<.01, p<.001), whereas behavioral factors influenced aspects of career preparation, such as tool preparation, information collection, and practical effort(p<.001). Moreover, career decision levels (career assurance and career indecision) were found to affect information collection, a subcomponent of career preparation(p<.05, p<.01). Conclusion: Considering these factors and actively empathizing with and counseling students would lead to effective career guidance in the field of Emergency Medical Services.