• Steel and Composite Structures
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• 제21권6호
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• pp.1389-1410
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• 2016

This paper proposes a hybrid of topological derivative-based level set method (LSM) and isogeometric analysis (IGA) for structural topology optimization. In topology optimization a significant drawback of the conventional LSM is that it cannot create new holes in the design domain. In this study, the topological derivative approach is used to create new holes in appropriate places of the design domain, and alleviate the strong dependency of the optimal topology on the initial design. Furthermore, the values of the gradient vector in Hamilton-Jacobi equation in the conventional LSM are replaced with a Delta function. In the topology optimization procedure IGA based on Non-Uniform Rational B-Spline (NURBS) functions is utilized to overcome the drawbacks in the conventional finite element method (FEM) based topology optimization approaches. Several numerical examples are provided to confirm the computational efficiency and robustness of the proposed method in comparison with derivative-based LSM and FEM.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1615-1617
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• 2009

The water resources project of 320 Ha second stage reclamation, in which including an University City, out of 800 Ha Ndata Farm, Malawa, had been under studied in this research. The challenge of C value of runoff coefficient was obtained as 0.8, by introducing the attenuation factors method, proposed by second author, an IDF dimensionless method customary used in Taiwan, proposed by the third author, is translated further to solve the project design rainfall; Rational Method, thus, obtains 11.5 CMS as the 5 year recurrence storage. The final job, completed by the third author's on-site performance, includs field alignments and discussions with the trustee, Malawa President H. E. Dr. Bingu Wa Mutharika, when a special concern of anti-theft. In order to provide sufficient supply up to an amount of 44,000 M3 during April to November, the sketch package includes 6 measurements: one water barrage, one sluice gate, one intake, one sediment reservoir, one water reservoir, and 3199 Km long gravity-driving hydraulic pipe.

• 융합보안논문지
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• 제12권5호
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• pp.79-85
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• 2012

본 연구는 디지털 포렌식 전문인력 양성을 위한 교육과정을 개선하는데 그 목적이 있다. 이를 위해 디지털 포렌식 전문인력 양성을 위한 교육과정을 제시하고 그 제시된 교육과정을 포렌식 전문가를 대상으로 설문조사를 실시해 얻은 결과를 AHP 기법을 활용하여 교육과정의 요소(포렌식개론, 시스템 포렌식, 종류별 이론 및 분석, 도구사용법, 조사실무)중 가장 합리적이고 중요도가 높은 교육과정인지를 도출할 수 있었다. 이와 같은 연구를 통해 도출된 합리적이고 중요도가 높은 교육과정을 반영하여 디지털 포렌식 전문인력 양성을 위한 교육과정을 개선하고자 한다.

• 대한토목학회논문집
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• 제11권4호
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• pp.9-15
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• 1991

본 연구는 도로교량들의 효율적인 안전도 명가 및 내하급수 판정 전산화 시스템을 개발하는데 그 목적이 있다. 이를 위해 현행 도로교 내하급수 체계를 합리적으로 개선한 후 외관조사 또는 가용 통계자료 만으로 안전성 평가를 실시할 수 있는 신뢰성 방법에 기초한 합리적인 내하력 평가방법을 제시하고 비상작전시 군용차량의 설제적인 허용통과 급수 판정시스템을 개발하였다. 연구결과 본 연구에서 제시된 내하력 및 내하급수 판정시스템, 그리고 내하력 평가 프로그램 BRS(Bridge Rating System)은 교량의 노후도와 각종 불확실량을 체계적으로 반영한 실 내하력 평가수단으로서 장차 교량의 안전성 및 내하력 평가에 널리 활용될 수 있다고 사료되었다.

• 농촌계획
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• 제2권1호
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• pp.31-38
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• 1996

As a rational decision-making process of county-level area development, this study designed 3-step framework : function-giving(areal analysis) on unit planning area by decision matrix of land suitability, check of typical characteristics of each function area and formulation of its future development strategies. Two alternatives were suggested as the areal analysis method, of which one is equal ordering / valuing technique of checking indices for land suitability classfication and the other preferential weighting technique. And then, under the algorithm specially defined in this study, land suitability maps(Fig.2,3) of the case study area (Seungju-county area, Chonnam-province, Korea) were drawn from the areal analysis results. By use of land suitability classification results, unique characteristics of typical function areas were defined (on 7 types of alternative 1 , 8 types of II ) and their future development strategies were formulated in the case study area, According to the categorization criteria in this study, all the villages of the case area were classfied as a suitable type of function areas illustrated in this study.

• Journal of Microbiology and Biotechnology
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• 제30권1호
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• pp.146-154
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• 2020

With the advantages of biocatalytic method, enzymes have been excavated for the synthesis of chiral amino acids by the reductive amination of ketones, offering a promising way of producing pharmaceutical intermediates. In this work, a robust phenylalanine dehydrogenase (PheDH) with wide substrate spectrum and high catalytic efficiency was constructed through rational design and active-site-targeted, site-specific mutagenesis by using the parent enzyme from Bacillus halodurans. Active sites with bonding substrate and amino acid residues surrounding the substrate binding pocket, 49L-50G-51G, 74M,77K, 122G-123T-124D-125M, 275N, 305L and 308V of the PheDH, were identified. Noticeably, the new mutant PheDH (E113D-N276L) showed approximately 6.06-fold increment of k_cat/Km in the oxidative deamination and more than 1.58-fold in the reductive amination compared to that of the wide type. Meanwhile, the PheDHs exhibit high capacity of accepting benzylic and aliphatic ketone substrates. The broad specificity, high catalytic efficiency and selectivity, along with excellent thermal stability, render these broad-spectrum enzymes ideal targets for further development with potential diagnostic reagent and pharmaceutical compounds applications.

• 한국정밀공학회지
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• 제18권9호
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• pp.61-70
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• 2001

This paper introduces a new digitization method with sensor fusion for shape measurement in reverse engineering. Digitization can be classified into contact and non-contact type according to the measurement devices. Important thing in digitization is speed and accuracy. The former is excellent in speed and the latter is good for accuracy. Sensor fusion in digitization intends to incorporate the merits of both types so that the system can be automatized. Firstly, non-contact sensor with vision system acquires coarse 3D point data rapidly. This process is needed to identify and loco]ice the object located at unknown position on the table. Secondly, accurate 3D point data can be automatically obtained using scanning probe based on the previously measured coarse 3D point data. In the research, a great number of measuring points of equi-distance were instructed along the line acquired by the vision system. Finally, the digitized 3D point data are approximated to the rational B-spline surface equation, and the free-formed surface information can be transferred to a commercial CAD/CAM system via IGES translation in order to machine the modeled geometric shape.

• 한국화재소방학회논문지
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• 제34권1호
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• pp.115-120
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• 2020

본 연구는 소방공무원이 지각하는 조직문화 유형과 조직지원인식이 조직몰입에 어떠한 영향을 미치는지 알아봄으로써 이들의 조직문화 유형에 따른 조직몰입을 높이고 조직차원에서의 지원에 관한 실천 방안을 마련하는데 도움을 주고자 하였다. 이를 위하여 경기 북부지역 소방공무원 205명을 대상으로 유의표집 방식으로 조사하였다. 조사결과, 소방공무원의 조직문화 유형 중 집단문화와 합리문화, 그리고 조직지원인식이 조직몰입에 통계적으로 유의미한 영향을 미치는 것으로 조사되었다. 본 연구결과를 토대로, 소방공무원이 지각하고 있는 집단문화와 합리문화의 활성화와 이에 따른 조직몰입을 높이고 조직차원에서의 다양한 지원방안에 대해 제안하였다.

• 한국측량학회지
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• 제21권3호
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• pp.255-260
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• 2003

본 논문에서는 2.5m 해상도를 갖는 SPOT-5 위성의 HRG(High Resolution Geometric) Supermode 입체 영상에 대해 3차원 센서모델을 제작하였으며, 센서모델로부터 계산된 외부표정요소를 이용하여 근실시간적으로 지형정보 획득이 가능한 RPC(Rational Polynomial Coefficients) 모델을 제작하였다 2개의 HRG 센서로부터 촬영된 5m 해상도 영상을 이용하여 2.5m 해상도 영상을 제작하는 Supermode 처리 영상의 센서모델링을 위해 이전 SPOT 계열의 선형 CCD array영상에 적용한 공선조건에 의한 번들조정 방법을 적용할 수 있음을 확인하였으며 정확도는 rmse 3.3m 이내였다. 또한 센서모델로부터 계산된 RPC 모델이 센서 모델을 대체할 수 있을 정도의 rmse 0.03m 정확도를 가질 수 있음을 실험을 통해 확인하였다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제5권3호
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• pp.431-453
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• 2013

The principal purpose of this paper is to present a novel two phases rational scenario applied in constructing an offshore monopod platform; in which the two phases are the all-ground horizontal construction phase and the post-construction phase. Concerning the all-ground construction phase, a brief investigation of its different stages, i.e., pre-fabrication, fabrication, pre-assembling, positioning, assembling, and surface finishing is introduced. The important practical aspects of such construction phase are investigated without going into the nitty-gritty of the details involved therein. Concerning the post-construction phase, a clear investigation of its sequential stages, i.e., lifting, moving and up-righting is introduced. A finite element model (FEM) of the monopod platform is created to perform the structural analysis necessary to decide the suspension points/devices and the handling scenario during the various stages of the post-construction phase on a rational wise. Such structural analysis is performed within the framework of the three dimensional quasi-static modeling and analysis aiming at simulating the realistic handling condition, and hence introducing a reliable physical interpretation of the numerical results. For the whole effort to be demonstrated efficiently, the results obtained are analyzed, the conclusions are presented, and few related recommendations are suggested.