• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.40 no.10
• /
• pp.843-849
• /
• 2016

It has been shown that the adaptive grasp feature can be implemented by underactuated robotic hands with a minimal number of actuators. Following this approach, a new design of prosthetic hand is presented. A method is proposed for evaluating grasp performance using cylinders, spheres, and square bars of various sizes. The effects of the major design parameters were investigated experimentally and an improved design is proposed.

• The Korean Journal of Applied Statistics
• /
• v.6 no.2
• /
• pp.303-309
• /
• 1993

In this paper we have defined two approaches to be error-robust when the precise form of error-structure is unknown. An experiment is optimal by the first criterion if it maximizes the minimum effciency over all candidates of error structure and is optimal by the second if it maximizes the minimum average of the efficiency over all candidates of error structure. In order to appreciate the basic implications of each design criterion, these approaches are applied to two different experimental situations, D- and heteroscedastic G-optimalities.

• Journal of Intelligence and Information Systems
• /
• v.13 no.3
• /
• pp.63-82
• /
• 2007

In this paper, we propose an adaptive hybrid genetic algorithm (ahGA) approach for effectively solving multistage-based scheduling problems in flexible manufacturing system (FMS) environment. The proposed ahGA uses a neighborhood search technique for local search and an adaptive scheme for regulation of GA parameters in order to improve the solution of FMS scheduling problem and to enhance the performance of genetic search process, respectively. In numerical experiment, we present two types of multistage-based scheduling problems to compare the performances of the proposed ahGA with conventional competing algorithms. Experimental results show that the proposed ahGA outperforms the conventional algorithms.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2020.06a
• /
• pp.405-405
• /
• 2020

최근 선제적인 가뭄대응을 위하여 관계부처가 상시 가뭄 관리체계를 지속하고, 범정부적 가뭄예방 대처를 위한 가뭄종합대책이 수립되었다. 가뭄종합대책에는 통합적 가뭄 위기대응체계를 마련해 단계별로 가뭄에 체계적으로 대응하고, 극한가뭄에 대비해 선제적 용수확보와 가뭄 전문가 지역 협의체 운영 등을 통해 대응 역량을 강화하는 계획이 포함되어있다. 또한 국가재난관리체계에 따라 지자체는 지역별 재난안전대책본부를 수립하고, 현장조치 행동메뉴얼에 따라 단계별 제한급수대책 수립, 재난대응 단계별 행동요령 (징후 감지, 초기 대응, 비상 대응) 등을 수행한다. 이처럼 가뭄은 발생 후 해갈까지 많은 시간과 지속적인 관리가 필요하며, 사회전반에 걸처 영향을 주는 대형복합재난으로 국가적 차원의 통합적 관리가 필요한 재난으로 국가가뭄대응체계 및 비상대처계획 (Emergency Action Plan, EAP) 수립이 필요하다. 미국은 1998년 국가가뭄정책법(National Drought Policy Act)을 제정해 가뭄관리에 대한 법제도적 기반을 마련하였으며, 2006년 국가통합가뭄정보시스템법 (National Integrated Drought Information System Act)을 제정해(Public Law 109-430) 현재의 국가통합가뭄정보시스템 (NIDIS)이 설립되었다. 이후 국가가뭄회복력파트너십 (National Drought Resilience Partnership, NDRP)을 발족하여 2016년 장기가뭄 회복력을 위한 국가재해대응정책을 수립하였다 (Federal Action Plan for Long-Term Drought Resilience). 미국의 경우 1982년 콜로라도 주, 사우스다코타 주, 뉴욕 주를 시작으로 2020년 현재 48개 주에서 연방정부단위의 가뭄대응계획을 수립하였다. 본 연구에서는 미국에서 실행되고 있는 가뭄 적응 대책 및 비상대처계획을 조사, 분석하고, 향후 메가 가뭄 발생시 국가단위의 가뭄 재난위기관리 매뉴얼, 정부 및 지자체의 가뭄 대응 체계 및 대응 방안을 보완할 수 있는 방안을 제시하고자 한다.

• Journal of Digital Convergence
• /
• v.14 no.10
• /
• pp.339-348
• /
• 2016

The purpose of this study was to identify the Kolb's learning style and preference for instructional methods of undergraduate nursing students. Data were collected from 174 students at a university in D city using a structured questionnaire from October 19 to October 21 2015. Learning style ratio of nursing students was accommodator 34.5%, converger 33.9%, assimilator 16.1%, diverger 15.5% and preference scores for instructional methods were discussion 7.27, direct instruction 7.26, peer teaching 7.22, independent study 6.54, project 6.25, instruction through technology 5.77, game 5.45, simulation 4.23. A significant difference was found in experience of flipped learning between four learning styles groups of nursing students. However, there was no significant difference in the preference of instructional methods between the four learning styles groups. Most of the students were in the middle range of the learning styles. The assessment of nursing students' learning styles is expected to help educator to plan teaching strategies.

• The Korean Journal of Applied Statistics
• /
• v.1 no.1
• /
• pp.21-28
• /
• 1987

In agricultural research field experiments are usually conducted with the sam etreatments in the same experimental design over several locations for several years in order to draw widely adaptable results. For generalization of the results from the individual locations and the properties of the treatment responses may be evaluated by carrying out the combined analysis over agricultural climate zones or country level. A method of combined analysis of variance was presented and examined by applying to a set of data obtained from a series of rice variety adaptability trials conducted by Kyung Buk Provincial Office of Rural Developmention 1986.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.29 no.9 s.240
• /
• pp.1217-1224
• /
• 2005

To improve the accuracy of a metamodel, additional sample points can be selected by using a specified criterion, which is often called sequential sampling approach. Sequential sampling approach requires small computational cost compared to one-stage optimal sampling. It is also capable of monitoring the process of metamodeling by means of identifying an important design region for approximation and further refining the fidelity in the region. However, the existing critertia such as mean squared error, entropy and maximin distance essentially depend on the distance between previous selected sample points. Therefore, although sufficient sample points are selected, these sequential sampling strategies cannot guarantee the accuracy of metamodel in the nearby optimum points. This is because criteria of the existing sequential sampling approaches are inefficient to approximate extremum and inflection points of original model. In this research, new sequential sampling approach using the sensitivity of metamodel is proposed to reflect the response. Various functions that can represent a variety of features of engineering problems are used to validate the sensitivity approach. In addition to both root mean squared error and maximum error, the error of metamodel at optimum points is tested to access the superiority of the proposed approach. That is, optimum solutions to minimization of metamodel obtained from the proposed approach are compared with those of true functions. For comparison, both mean squared error approach and maximin distance approach are also examined.

• Journal of KIISE:Computer Systems and Theory
• /
• v.37 no.3
• /
• pp.127-137
• /
• 2010

As large-scale computational applications in various scientific domains have been utilized over many integrated sets of grid computing resources, the difficulty of their execution management and control has been increased. It is beneficial to refer job history generated from many application executions, in order to identify application‘s characteristics and to decide selection policies of grid resource meaningfully. In this paper, we apply a statistical technique, Plackett-Burman design with fold-over (PBDF), for analyzing grid environments and execution history of applications. PBDF design identifies main factors in grid environments and applications, ranks based on how much they affect to their execution time. The effective factors are used for selecting reference job profiles and then preferable resource based on the reference profiles is chosen. An application is performed on the selected resource and its execution result is added to job history. Factor's credit is adjusted according to the actual execution time. For a proof-of-concept, we analyzed job history from an aerospace research grid system to get characteristics of grid resource and applications. We built JARS algorithm and simulated the algorithm with the analyzed job history. The simulation result shows good reliability and considerable performance in grid environment with frequently crashed resources.

• Journal of Korean Society of Water and Wastewater
• /
• v.33 no.6
• /
• pp.421-428
• /
• 2019

This study developed an evaluation system of adaptation countermeasures for climate change in the water resources sector using the Analytic Hierarchy Process (AHP), and the assessment procedures were applied to the Second Chungcheongnam-do Climate Change Adaptation Implementation Plan (Chungnam Implementation Plan). Firstly, the evaluation criteria are composed of two levels according to the hierarchical structure, and AHP gives priority to 4 evaluation criteria of the first level and 16 alternative indicators of the second level. Secondly, after the importance of the evaluation criteria or indicators has been determined, the significance of each measure was evaluated by applying it to the water-sector measures of the Chungnam Implementation Plan, and the effectiveness of the evaluation system was validated. The Chungnam case study shows that the evaluation system will be more effective and efficient when it is applied during development phase rather than after the implementation plan is finalized. It is also expected that the evaluation system will be used to evaluate and prioritize climate change adaptation policies in other regions, and then to compare the means of adaptation to climate change in various regions and to select recommendation policies.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.37 no.5
• /
• pp.311-318
• /
• 1988

An adaptive control problem for a plant with unmodelled dynamics is studied. The upper bounds of the output due to the unmodelled dynamics and measurement noise is assumed to be known. This problem was studied by Middleton et al. They used a modified form of the least square method in estimating the plant paramaters. In this paper, the bounds of the parameters are estimated by linear programming and the parameters are estimated by the projetion type algorithm incorporating the bounds of the parameters. The stability of the proposed adaptive control system can be proved in nearly the same way as the proof of Middleton. The performance of the proposed method is found to be much better than the method of Midlleton's with respect to the parameter convergence and plant output in computer simulations.