• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.386-391
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• 2001

A finite element code based on P2P1 tetra element has been developed for the large eddy simulation (LES) of turbulent flows around a complex geometry. Fractional 4-step algorithm is employed to obtain time accurate solution since it is less expensive than the integrated formulation, in which the velocity and pressure fields are solved at the same time. Crank-Nicolson method is used for second order temporal discretization and Galerkin method is adopted for spatial discretization. For very high Reynolds number flows, which would require a formidable number of nodes to resolve the flow field, SUPG (Streamline Upwind Petrov-Galerkin) method is applied to the quadratic interpolation function for velocity variables, Noting that the calculation of intrinsic time scale is very complicated when using SUPG for quadratic tetra element of velocity variables, the present study uses a unique intrinsic time scale proposed by Codina et al. since it makes the present three-dimensional unstructured code much simpler in terms of implementing SUPG. In order to see the effect of numerical diffusion caused by using an upwind scheme (SUPG), those obtained from P2P1 Galerkin method and P2P1 Petrov-Galerkin approach are compared for the flow around a sphere at some Reynolds number. Smagorinsky model is adopted as subgrid scale models in the context of P2P1 finite element method. As a benchmark problem for code validation, turbulent flows around a sphere and a MIRA model have been studied at various Reynolds numbers.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.1129-1134
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• 2001

In the point of the Eco-concrete(Environmentally Friendly Concrete), it is very important to reduce the pH of high porous concrete by the pH to be able to grow plants, because the pH of concrete is l1~13. But the method of measuring the pH of high porous concrete is not well-defined, yet. Therefore, first, this paper report the method of measuring the pH of high porous concrete. Secondly this paper reports the pH reduction of high porous concrete to grow plants.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.290-295
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• 1992

Tendon driven method to drive one joint using two actuators is developed and implemented. While the method has advantages over conventional transmissions, it also has several drawbacks like tendon slack, elongation and endurability. In this paper, a compensation method of the intrinsic non-linearities of tendon is proposed to improve the performance of antagonistic tendon driven method. In this method, tendon tension measurement is prerequisite which is measured with strain gauge type tension sensor. The developed method is implemented on one link test bed with colocated and non-colocated position sensor.

• Child Health Nursing Research
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• 제10권3호
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• pp.251-261
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• 2004

Purpose: To investigate the degree and sources of stress which fathers of infants in NICU experience. Method: Eighty-five fathers of NICU infants at 5 university hospitals in Seoul volunteered to complete the Parental Stressor Scale for NICU (PSS: NICU) from September 1, to October 15, 2002. Result: Total perceived stress was 3.50±0.76. The highest score were in Parental Role Alteration (3.76±0.83) and Appearance and Behavior (3.65±1.04). The total perceived stress score (PSS), correlated significantly with method (t=3.50, p=.01), and route (F=5.30, p=.00) of feeding. Light & Sound correlated significantly with birth weight (F=3.39, p=.02), medical diagnosis(F=2.30, p=.03), plan of operation(t=2.50, p=.01), operation (t=3.80, p=.02), method (F=4.90, p=.003), and route (F=4.70, p=.00) of feeding. Infant Appearance and Behavior correlated significantly with birth weight (F=5.12, p=.01), plan of operation (t=2.50, p=.01), method (F=3.50, p=.01), and route (F=7.80, p=.00) of feeding. Parental Role Alteration correlated significantly with care of incubator (t=-.68, p=.03), method of feeding (F=2.80, p=.04) and education level of father (F=3.00, p=.05). Conclusion: Father with NICU infants were concerned mostly with parental role alteration and infant appearance. Nursing intervention should include fathers of NICU infants.

• 한국음향학회지
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• 제42권1호
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• pp.1-6
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• 2023

구조진동 소음 문제의 평가에 있어 방사소음은 중요한 물리적 특성으로 음향 인텐시티 측정으로 확인이 가능하지만, 시간이 오래 걸리고 까다로운 측정 조건 때문에 시험을 꺼리는 경향이 많다. 그 대안으로 시뮬레이션이 사용되고 있으며, 그 정확도도 높다. 문제는 방사소음 파워와 방사효율 같은 중요한 물리량을 얻기 위해서는 이를 계산해 주는 특정한 소프트웨어가 필요하다는 점이다. 본 연구에서는 이런 관점에서 일반적인 유한요소 해석 소프트웨어를 사용하여 방사소음 파워와 방사 효율을 계산하는 후처리 기법을 제안한다. 제안된 두가지 방법은 기본적으로 시험에서 사용하는 방법을 시뮬레이션에 활용하는 것이다. 첫번째 방법은 상반성 기법을 이용하는 것이며, 두번째 방법은 인접한 2개의 위치에서 계산된 음압을 이용하는 방법이다. 두가지 방법이 모두 효과적으로 방사소음 파워를 예측할 수 있음을 보였으며, 그 한계도 설명하였다.

• 복식
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• 제33권
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• pp.217-228
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• 1997

The purpose of this study was to investigate influence of the construction method of the circular skirt on drapability and shape of static silhouette and length variation. In made 24 types of skirts giving the variations (six kinds of peach skin-like finished fabrics two types of cutting method two types of machine stitch method of hem), The results were as follows: 1. Analysis of drapability In the cutting method thre was similarity between warp direction and true bias direc-tion. In the machine stitch method of hem there was similarity between blind stitch and blind stitch machine. According to the fabrics analysis of drapability was excellent in the order N/P 80/20(fabric 1)>P 100(fabric 5)>P 100(fabric 6)>P 100 (fabric 2)>P 100 (fabric 4)>N/C 50/50(fabric 3). 2. Analysis of the characteristics values of static silhouette shape In the cutting method shape of static sil-houette became wide in the warp direction. In the machine stitch method of hem shape of static silhouette became wide in the blind stitch. According to the fabrics shape of static silhouette became most wide in the N/C 50/50(fabric 3) and shape of static sil-houette become most narrow in the P 100(fabric 2,5) 3. Analysis of the length variation In the cutting method the true bias direc-tion was longer than the warp direction. In the machine stitch method of hem there was simi-machine stitch method of hem there was simi-larity between blind stitch and blind stitch ma-chine. In fabrics the P 100(fabric 6) showed the longest the N/C 50/50(fabric 3) showed most slight. Interaction between the cutting and messure-ment part of skirt lengh. In the warp diretion parts that showed longest length variation were C. G, K, O in the true bias diretion parts that showed most slight length variation were A, E, M, I.

• 한국환경보건학회지
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• 제40권1호
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• pp.55-62
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• 2014

Objectives: $^{32}P$-postlabeling assay is the most sensitive method of detecting DNA adduct formation. However, it is limited by a low sample throughput and use of radioisotopes (RI). In this study, we modified it to minimize these limitations and applied it to Z. platypus exposed to Benzo(a)pyrene (BaP) in order to investigate DNA adduct formation (effect biomarker for pollutants) in Z. platypus for assessing risk of waterborne BaP exposure. Methods: DNA hydrolysis was performed only with Micrococcal nuclease (MNase), RI reduction test was performed and the overlapping steps between thin layer chromatography (TLC) and radioisotope high-performance liquid chromatography (RI-HPLC) were omitted. The application of a modified method to Z. platypus exposed to BaP was performed. Results: The results revealed that the amount of RIs used can be reduced roughly 10-fold. Because the analysis time was shortened by 8.5 hours, the sample throughput per hour was increased compared with the previous method. The results of applying modified $^{32}P$-postlabeling assay to Z. platypus, DNA adduct formation in Z. platypus showed dose-dependency with the BaP concentration. Only BPDE-dGMP was detected as a DNA adduct. Conclusion: These results demonstrate that the modified $^{32}P$-postlabeling assay is a suitable method for detecting DNA adduct formation in Z. platypus exposed to waterborne BaP and will be useful in risk assessment of carcinogenic effect in aquatic environment due to BaP.

• 대한교통학회지
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• 제19권5호
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• pp.99-108
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• 2001

본 논문은 유류저장탱크의 최적입지를 선정하기 위한 GIS와 OR 통합적용기법을 제시하며, P-Median heuristic method와 MIP method가 모두 유류저장탱크의 최적입지 선정 문제에 적용될 수 있음을 실증하였다. 또한, 두 접근 방식에 의해 확인된 결과들은 동일하였다. P-Median heuristic method와 MIP method 를 풀이하는데 필요한 최단거리 매트릭스를 계산해내 기 위해 GIS기반 도로망과 해운네트워크를 구축·결합하였으며, 두 접근방법을 통해 우리나라의 최적 유류저장탱크의 입지를 선정한 결과 권역별로 군산항, 여수항, 부산항, 옥계항이 선정되었다. 위와 같이, 본 연구를 통해 CIS와 P-Median heuristic method, MIP method의 적용은 실증되었으며, 유사한 연구 또한 GIS와 OR의 통합적용을 통해 수행될 수 있을 것이다.

• 대한수학회지
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• 제60권1호
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• pp.1-32
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• 2023

In this paper, we present a method of characterizing minimal polynomials on the ring 𝐙_p of p-adic integers in terms of their coefficients for an arbitrary prime p. We first revisit and provide alternative proofs of the known minimality criteria given by Larin [11] for p = 2 and Durand and Paccaut [6] for p = 3, and then we show that for any prime p ≥ 5, the proposed method enables us to classify all possible minimal polynomials on 𝐙_p in terms of their coefficients, provided that two prescribed prerequisites for minimality are satisfied.

• 응용통계연구
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• 제26권5호
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• pp.797-806
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• 2013

메타분석은 이전의 연구들의 결과를 결합하기 위해 많은 분야에서 널리 사용된다. 메타분석 방법들 중에 p-value의 통합은 가장 단순한 방법이며 Tippett (1931), Fisher (1932) Stouffer 등 (1949) 등이 p-value를 통합하는 다양한 방법들을 제안하였다. 이 논문에서 우리는 지수분포에 기초한 새로운 p-value의 통합 방법을 제안하였다. 또한, 몬테카를로 모의시험 연구를 통해 제안된 방법과 이전의 방법들의 검정력을 비교하였다.