태재시에 나타난 자연의 공간적 의미 연구

류근안 국어국문학회 2003 국어국문학 Vol.- No.134

The purpose of this dissertation is how the image of nature was transfigured and sho주l in Yu Bang-sun. As he is poet who has lived his all life in exile and seclusion, it is essential to survey his recognition of natural in order to understand him. The period of his age was that of a chaos of dynasty replacement. As a result, he lived long in seclusion because of his father's sin. And he died without being join in a world even after being released. The image of nature appears variously in his poems. His view of nature couldn't but be special, for he lived all his life in nature. First of all, nature was the place of his life. It was completely different from Taoists's nature of enjoyment, and it was also the scene of life itself Secondly, it was nature as a space separated from the real world, namely, it makes him feel all the more being alone and trouble with it. Thirdly, it was nature that keeps him from the real world, that is, it was as a protective device that protects himself from the troubled times. Fourthly, it was harmonious nature that takes relief of life, that is, it was natural that is not only his friend but also roe body as a space of the objective world and self in a body.

A Study on the Comparison of wind pressure on the member of Container Crane using Wind tunnel test and CFD

한근조,안태원,이성욱,한동섭 동아대학교 생산기술연구소 2006 生産技術硏究所硏究論文集 Vol.11 No.-

Because strong wind is one of the few forces that, although considered in container crane design, still cause significant damage, a container crane was tested to investigate wind load characteristic in uniform flows. So, this study measured an external point pressure at the each members of a container crane according to a wind direction and a shape of members in a wind-tunnel test. The result of this test was compared to those of computation fluid dynamics using a CFX 10. The scale of a container crane model for wind tunnel test applied similarity scales to consider the size of the wind tunnel test section and the boundary condition for CFD is like wind tunnel test.

초정밀 마이크로 물성평가를 위한 비전변형률 측정모듈 개발

한아름,이혜진,이낙규,이근안,송정한 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

Researches about micro technology travel lively in these days. Such many researches are concentrated in the field of micro materials and a process field. But properties of micro materials should be known to give results of research developed into still more. In these various material properties, reliability data such as mechanical, optical, thermal property, etc is the basic property. In this paper, it is developed that is Strain measurement module for micro material property system.

불확실성, 공급사슬전략, 운영성과의 관계

안봉근 ( Bong Geun An ) 한국경영공학회 2015 한국경영공학회지 Vol.20 No.2

Today’s business environment is characterized by a high level of uncertainty. Uncertainty may arise from various dimensions: market, technological and customer uncertainties. In such an environment, an organization is required to have a multi-dimensional strategy for its survival and growth. This study suggests a supply chain strategy as a critical leverage for an organization to cope with the environmental uncertainty. To investigate the effect of supply chain strategy on an organization performance, structural equation modeling is employed to empirically test the relationship among uncertainty, supply chain strategy, and operational performance. In this study, we highlight that both short-term adaptation and long-term growth should be pursued at the same time with improvement of the existing supply chain by implementing exploitation strategy and development of the opportunity for a new supply chain by employing exploration strategy against uncertainty. Empirical results show that causal relationships from the uncertainty through supply chain strategy to operational performance are statistically meaningful. A summary of the results, implications of this study, and suggested future research are presented in the conclusion.

Optimal Decision on a Stochastic(Q, R)Inventory System for ARMA Demand

An,Bong-Geun 啓明大學校 産業經營硏究所 1993 經營經濟 Vol.26 No.1

日日需要와 注文期間이 모두 確率變數일 때 (Q,R) 재고관리시스템 의사결정변수인 주문량(Q)과 재주문점(R)을 결정하기 위해 주문기간중 수요(L)의 確率分布가 필요하다. 일일수요가 서로 독립이고 동일한 확률분포(i.i.d)를 갖는다는 가정하에서 L의 확률분포를 구하는 방법이 기존 연구에서 제시되었으나, 일일수요가 時系列 자료임을 감안하면 일일수요가 i.i.d.가 아니고 자기상관성을 보이는 경우가 대부분이다. 따라서 본 연구에서 일일수요가 임의의 自己回歸移動平均(ARMA) 형태로 표시되고 주문기간이 확률변수일 때, 주문기간중 수요(L)를 i.i.d. 오차확률변수(random error)의 선형결합으로 표시하고 L의 평균과 분산을 구하는 공식을 유도하였다. 또한 (Q,R) 재고시스템의 연간 기대재고비용을 의사결정변수의 함수로 표시하고 L의 확률분포가 주어진 경우 재고비용이 최소되는 최적해를 구하는 반복과정을 제시하였다. 수요가 ARMA과정을 따를 때 유도된 L의 평균과 분산을 근거로 L의 확률분포를 정규분포, Gamma분포 및 대수정규분포로 근사화하는 과정을 제시하였다. 수치분석에서 일일수요가 AR(1) 과정을 따르고 주문기간이 기하분포일 때 근사화된 L의 확률분포를 이용하여 재고비용이 최소되는 최적주문량과 최적주문량을 구하고 자기상관계수가 최적주문량, 최적주문량 및 재고비용에 미치는 영향을 조사하였다. 이 연구에서 발견된 사항은 (1) 자기상관계수가 최적주문량, 최적주문량 및 재고비용에 큰 영향을 미치며, 일일수요의 자기상관성을 고려하지 않는 경우 심각한 정도의 잘못된 의사결정을 유도하며 (2) 년간 수요를 고정시킨 경우 자기상관성은 최적주문점에 영향을 미치나 최적주문량과 재고비용에는 영향을 주지 않는다.

Multi-active sites of iron carbide nanoparticles on nitrogen@cobalt-doped carbon for a highly efficient oxygen reduction reaction

An, Geon-Hyoung,Lee, Young-Geun,Ahn, Hyo-Jin Elsevier 2018 JOURNAL OF ALLOYS AND COMPOUNDS Vol.746 No.-

<P><B>Abstract</B></P> <P>The design of a low-cost, stable, and highly efficient electrocatalyst using a non-precious material and carbon composites for oxygen reduction reaction (ORR) activity to replace platinum-based electrocatalyst is essential for future energy conversion devices, such as fuel cells and metal air batteries. However, previous efforts to acquire the high ORR activity by non-precious material and carbon composites faced substantial challenges due to a few active sites during electrochemical reactions. Herein, we synthesize an advanced composite of iron carbide nanoparticles on nitrogen and cobalt-doped carbon nanofiber (Fe<SUB>3</SUB>C/N@Co-doped CNF) by electrospinning, a precures coating process and carbonization. Fe<SUB>3</SUB>C/N@Co-doped CNF offers a high onset potential of 0.9 V, high half-wave potential (E<SUB>1/2</SUB>) potential of 0.8 V, and a nearly four-electron pathway (<I>n</I> = 3.9). Therefore, this unique composite provides multi-active sites using the doping system and metal carbide nanoparticles for the ORR activity, as well as an outstanding tolerance to methanol crossover.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Unique composite as an electrocatalyst with multi-active sites. </LI> <LI> Iron carbide nanoparticles on nitrogen and cobalt-doped carbon nanofiber. </LI> <LI> Existence of pyridinic−N and of Co−N−C within carbon nanofiber. </LI> <LI> Well-dispersed iron carbide nanoparticles. </LI> <LI> Platinum-free electrocatalyst with excellent electrochemical performance. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

공기 다단 분무연소기의 NOx 발생특성에 관한 실험적 연구

김한석,안국영,김호근,백승옥,Kim, Han-Seok,An, Guk-Yeong,Kim, Ho-Geun,Baek, Seung-Ok 한국기계연구원 2001 硏究論文集 Vol.31 No.-

An experimental investigation on the reduction of nitrogen oxide emission from swirling, turbulent diffusion flames was conducted using multi air staged combustor, The combustor utilizes swirler to dampen fuel/air mixing, allowing an extended residence time for fuel pyrolysis and fuel-N conversion chemistry in an locally fuel-rich environment prior to burnout. This process also allow to reduce thermal NOx formation to lessen the temperature of reaction zone. The aerodynamic process therefore emulates the conventional staged combustion process, but without the need for the physically separate fuel-rich and -lean stages. Parametric studies on the ratios of each staged air and droplet size were carried out the feasibility of fuel/air mixing for low NOx combustion with diesel and pyridine mixed diesel fuel oil.

재실자 행동을 고려한 발코니 결로 발생 환경 분석

안선근(An, Sun-Geun),이준혜(Lee, June Hae),여명석(Yeo, Myoung-Souk) 대한건축학회 2018 대한건축학회 학술발표대회 논문집 Vol.38 No.1

The purpose of this study was to analyze the balcony condensation occurrence environment considering occupant behavior. Field measurement at the balcony facing kitchen and outdoor was done in February. During the observation period, condensation mostly occurred when the balcony door was opened during the use of kitchen. Also, even though the balcony door was closed, condensation occurred when vapor producing activity was done in the balcony. But condensation did not occur for the all cases above. It is analyzed that condensation occurrence is affected by various elements such as indoor humidity, balcony humidity, balcony door opening time and degree, vapor production rate and time in the balcony.

Empirical Distribution Method on Reorder Point Determination for ARMA Demand

An, Bong-Geun 啓明大學校 産業經營硏究所 1997 經營經濟 Vol.30 No.2

재고고갈확률(Stockout Probability)이 주어진 재고관리시스템에서 발주점(Reorder Point)을 결정하기 위하여 발주기간 중 수요(L)의 확률분포가 필요하다. 그러나 수요가 시계열 형태의 자기회귀이동(ARMA) 모형을 따르고 발주기간이 확률적으로 변동시 L의 분포를 유도하거나 추정이 매우 어려워 기존 문헌에서 여러 가지 근사분포를 제시하고 있으나 그 방법의 복잡성으로 현장에서 이러한 기법을 활용하기가 매우 어렵다. 본 논문에서 전통적 방법에 의한 발주점의 실증분포(Empirical distribution)를 근거로 한 표본분위수(Sample quantile)와 모형화 과정이 불필요한 Bootstrap 절차에 의하여 추정된 실증분포를 근거로 한 표분분위수 이용방법을 기존 방법의 대체안으로 제시하였다. 본 논문에서 추정된 발주점의 누적확률과 표본표준편차를 근거로 제안된 두 방법의 정확도와 안정성을 비교평가 하였다. Bootstrap 방법은 표본의 크기가 적은 경우에도 만족할 만한 수준의 정확도와 안정성을 갖는 추정량을 제시한다. 반면 전통적 방법에 의한 실증분포 사용할 때 표본크기가 적을 때 재주문점 추정량의 변동성이 매우 크게 나타났으며, 표본의 크기가 증가하면 그 변동성이 감소한다. 또한 본 수치분석의 예에서 표본크기가 10으로 표본의 크기가 작은 경우 두 가지 방법 모두 재주문점을 과소 추정하는 경향을 보였다. 결론적으로 Bootstrap 방법은 사용이 간단하고 그 정확도와 안정성 면에서 상당히 우수하며, 이에 대비하여 전통적 실증분포 사용방법은 적은 표본크기에서 변동성이 매우 크므로, 이 방법은 표본의 크기가 매우 클 경우에만 사용되어야 한다.

비교연산을 통한 이미지 인식에 관한 연구

박현근(Hyeon-Geun Park),안영기(Young-Ki An),장일기(Il-Ki Jang),이희석(Hee-Suk Lee),이상문(Sang-Moon Lee) 한국컴퓨터정보학회 2011 한국컴퓨터정보학회 학술발표논문집 Vol.19 No.2

영상처리 기법을 이용한 이미지 인식에 관한 컨텐츠들은 아주 다양한 알고리즘을 사용하였다. 영상처리 기법에서 이미지 인식기법 중에서 일반적인 것으로는 PCA(Principal Component Analysis) 알고리즘이 있다. 이 알고리즘이 적용된 대표적인 컨텐츠로는 얼굴 문자인식이 있다. 이 알고리즘은 정확성을 위하여 학습을 통한 영상의 저장과 인식을 통한 복잡한 알고리즘을 사용한다. 간단한 이미지 인식 컨텐츠의 경우에 복잡한 알고리즘을 사용함으로써, 시스템 처리속도에 영향을 줄 수 있다. 따라서 이 논문에서는 비교연산을 수행하는 히스토그램 매칭을 두 가지 실험 방법을 통하여, 간단한 이미지인식 시스템을 위한 알고리즘을 설계한 것이다.