• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XII)
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• pp.228-232
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• 2003

Lovastatin produced by Aspergillus terreus via polyketide pathway is a secondary metabolite with high anti-hypercholesterolemic activity. In this paper we are going to present effective strain development strategies for lovastatin production by comparing the productivity of the mutants obtained through traditional rational screening process and protoplast fusion method. Mutants resistant against various antibiotics and/or antimetabolites showed significantly higher lovastatin productivity than the corresponding mother strains, demonstrating that rational screening method was very efficient in selecting high yielding producers. Recombinant fusants obtained using protoplast fusion between high producers were observed to have very different morphology and physiology as represented by the production and secretion of lovastatin, as well as cell growth pattern. In parallel with the strain development, optimization process for the production medium was carried out in order to find optimal concentrations of the medium components using such a powerful statistical method as response surface method (RSM). It was concluded that not only the optimum production medium but also good morphological characteristics of the high-yielding producers led to higher lovastatin production.

• 디지털콘텐츠학회 논문지
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• 제10권2호
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• pp.189-198
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• 2009

이 논문에서는 직교 주파수분할 다중화(orthogonal frequency division multiplexing: OFDM) 수신기에서 수신 신호를 과표본화(oversampling)하여 성능을 개선하는 방법을 제안한다. 수신된 OFDM 신호를 복조하는 것은 각 부반송파에 해당하는 정현파 성분의 진폭과 위상을 추출하는 것과 동일하다. OFDM 수신신호를 과표본화 하면 주파수 영역에서 진폭은 동일하고 위상만 다른 신호를 과표본화율만큼 중복해서 얻을 수 있다. 이 성질을 이용하여 과표본화율만큼 신호대잡음비를 개선할 수 있다. 이 논문에서는 과표본화율이 정수인 경우만 가능하던 기존의 과표본화 방법을 일반적인 비정수로 확장하고 그에 적합한 수신기 구조를 제안하고자 한다. 또 모의실험을 통해 비이상적인 대역제한 필터를 사용하는 수신기의 성능을 비교함으로써 제안한 방식의 타당성을 보인다.

• 산업경영시스템학회지
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• 제32권4호
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• pp.153-160
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• 2009

In the research-oriented university there are various laboratories in the departments according to a major field of study. Under these circumstances the budget to purchase experimental facilities has only to be distributed among research teams and then is spent within the confines of it without rein. However, in case of college the budget for experimental facilities needs to be considered other allocation methods because of no laboratory being managed by professor. In this paper the methodology for the rational selection of experimental facilities for college is proposed. It is composed of the following ; (1) the rational allocation method of the budget for experimental facilities in consideration of the characteristics of individual departments, and (2) the evaluation and selection of the alternative experimental facilities submitting in each department. To decide rationally importance of estimation index for the determination of budget and equipment is applied the Analytic Hierarchy Process(AHP) technique. First the proposed methods are presented and then discussed with simulation results.

• 한국응급구조학회지
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• 제13권3호
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• pp.107-120
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• 2009

Purpose : The purpose of this study was to investigate the influence of organizational culture on job satisfaction of fire officials. Method : The subjects of this study were 251 fire officials in Gongju and Choengju province and Daejeon City. Data were collected using self-administering questionnaire from February 20 to March 20 in 2006. Collected data were analyzed using SPSS 14.0 program. Real number, percentage, mean and standard deviation were calculated, and t-test, ANOVA, Pearson correlation coefficient, multiple regression were analyzed. Result : The results of this study were as follows : 1. The job satisfaction was found to be significant positive correlations with full organizational culture(r = .595, p = .000). 2. The job satisfaction was found to be in significant positive with rational goal culture, open system culture and human relation culture. 3. How organizational culture affects the job satisfactions was as follows; 25.2% of core values of manpower, 6.3% of rational goal culture, and 4.9% of job initiative. Conclusion : Enhancing the job satisfaction of fire officials would improve personalized factors and changes rational goal culture.

• 문화기술의 융합
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• 제4권3호
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• pp.127-132
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• 2018

본 연구는 부산시 아파트 분양광고의 내용분석을 통하여 광고 표현의 메시지 지향성에 관하여 조사하였다. 부산지역 신문광고를 대상으로, 아파트 분양광고의 광고소구 방식 및 메시지 유형을 분석하였다. 브랜드(전국기반 브랜드, 지역기반 브랜드)에 따라 광고소구 방식(이성적 소구, 감성적 소구)과 메시지 지향성(환경지향성, 감성지향성, 투자지향성, 기능지향성)으로 분류하여 조사하였다. 연구결과, 부산시 대부분의 아파트 분양 광고가 이성적 소구를 사용한 것으로 나타났다. 전국기반 브랜드는 이성적 소구와 감성적 소구가 비슷하게 사용된 것에 비해 지역기반 브랜드는 이성적 소구의 사용이 큰 비중을 차지하였다. 광고 메시지 지향성은 투자지향성과 감성지향성의 비중이 가장 높은 것으로 나타났다. 경제적 이익이나 프리미엄을 나타내는 투자지향성 메시지의 사용이 가장 많은 것으로 나타났으며 그 다음으로 자부심, 행복을 나타내는 감성지향성 메시지의 사용이 높은 것으로 나타났다. 이러한 결과는 광고 표현 전략의 차이가 브랜드 간에 존재하는 것으로 해석된다. 이와 같은 연구 결과들은 아파트 분양광고의 메시지 전략에 유용한 실무적 시사점을 제공할 것으로 기대한다.

• Structural Engineering and Mechanics
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• 제73권6호
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• pp.641-649
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• 2020

The determination of midtower longitudinal stiffness has become an essential component in the preliminary design of multi-tower suspension bridges. For a specific multi-tower suspension bridge, the midtower longitudinal stiffness must be controlled within a certain range to meet the requirements of sliding resistance coefficient and deflection-to-span ratio. This study presents a numerical method to divide different types of midtower and determine rational range of longitudinal stiffness for rigid midtower. In this method, influence curves of midtower longitudinal stiffness on sliding resistance coefficient and maximum vertical deflection-to-span ratio are first obtained from the finite element analysis. Then, different types of midtower are divided based on the regression analysis of influence curves. Finally, rational range for longitudinal stiffness of rigid midtower is derived. The Oujiang River North Estuary Bridge which is a three-tower four-span suspension bridge with two main spans of 800m under construction in China is selected as the subject of this study. This will be the first three-tower four-span suspension bridge with steel truss girders and concrete midtower in the world. The proposed method provides an effective and feasible tool for engineers to design midtower of multi-tower suspension bridges.

• Structural Engineering and Mechanics
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• 제14권6호
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• pp.733-738
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• 2002

A simplified rational method is developed to evaluate transverse earthquake-induced forces in continuous bridges. This method models the bridge as a beam on elastic foundation, and assumes a sinusoidal curve for both vibration mode shape and deflected shape in the transverse direction. The principle of minimum total potential is used to calculate the displacements and the earthquake-induced forces in the transverse direction. This method is concise and easy to apply, and hence, offers an attractive alternative to a lengthy and time consuming three dimensional modeling of the bridge as given by AASHTO under its Single Mode Spectral Analysis Method.

• 한국조경학회지
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• 제20권2호
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• pp.119-126
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• 1992

The purpose of this study is to develop the allocation method which could be applied to the transitional stage between analysis and synthesis to select the best alternative in landscape planning process. By using the matrix of alternatives with site-planning elements locational drawing in each, the combinational allocation method can make the process more rational and also more efficient. Hand-drawn map overlay technique accommodates the work I handy way. The method is useful in building conceptual scheme in landscape planning especially when it is applied to small scale project.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.663-667
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• 2000

The equivalent load method has been widely used in the design and analysis of prestressed concrete structures. The purpose of this paper is to explore several important method of obtaining equivalent loads and to clarify the advantages and limitations of each method. The methods devised in this study include the use of curvature of tendon, characteristics of primary moment, self-equilibrium conditions, and linear segments approximation of tendon. It is shown that equivalent lading system is not uniquely determined in some cases and careful engineering judgement is required from the view point of accuracy and practical convenience.

• 한국음향학회지
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• 제36권1호
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• pp.1-11
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• 2017

본 연구에서는 두 변수 유리함수 근사법에 기반한 3차원 음향 포물선 방정식의 제곱근 연산자의 새로운 근사식을 제안한다. 이 근사식은 기존의 제곱근 연산자에 대한 근사 연구와 비교해서 두 가지의 장점을 가진다. 첫 번째는 광대역 각도 능력이다. 제안된 식은 방위각 $45^{\circ}$에서 3차원 음향 포물선 방정식의 거리 축으로부터 $62^{\circ}$까지 넓은 각도에 대해 정확도를 가지는데, 이 값은 기존에 연구된 3차원 음향 포물선 방정식 알고리즘의 각도 한계의 약 세 배이다. 두 번째로는 본 근사식의 분모는 수심과 횡 거리에 대한 연산자의 곱으로 표현된다는 점이다. 이러한 분할 형태는 3차원 포물선 방정식을 손쉽게 삼중대각행렬 방정식으로 변환할 수 있다는 점에서 수치해석에서 선호된다. 제안된 식의 성능을 검증하기 위해 위상 오차분석을 통해 타 근사법과의 비교 연구가 수행되었고, 제안된 방법은 가장 우수한 성능을 보였다.