• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1988년도 가을 학술발표회 논문집
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• pp.7-12
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• 1988

This study presents rational methods for probability-based estimates of basic design wind speeds in Korea and develops a risk-bases nation-wide map of design wind speeds. The paper examines the fitting of the Type-I extreme model to maximum yearly non-typhoon wind data from long-term records based on the conventional method and to maximum monthly nod-typhoon wind data from short-term records following Grigorin's approach. The paper also reviews the applicability of the method using short records of about 5 years. The basic design wind speeds for typhoon and non-typhoon wind at a station are made to be obtained from a mixed model which is given as a product of typhoon and non-typhoon extreme wind distributions. A practical method which is based on the fitting of the Type I model to records or typhoon and non-typhoon mixed wind data at a station is also preposed in this study.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1117-1119
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• 1999

This paper presents a new approach for the optimal routing problem of distribution system planning using the well known Hopfield Neural Network(HNN) method. The optimal routing problem(ORP) in distribution system planning(DSP) is generally formulated as combinational mixed integer problem with various equality and inequality constraints. For the exceeding nonlinear characteristics of the ORP most of the conventional mathematical methods often lead to a local minimum. In this paper, a new approach was made using the HNN method for the ORP to overcome those disadvantages. And for this approach, a appropriately designed energy function suited for the ORP was proposed. The proposed algorithm has been evaluated through the sample distribution planning problem and the simulation results are presented.

• 대한기계학회논문집A
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• 제23권11호
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• pp.1952-1959
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• 1999

The work factor approach, so-called single specimen technique could be used to determine energy release rate from a single test record for unidirectional CLS specimen. In the present study, the work factor approach was extended to determine the mixed-mode fracture toughness of multi-directional graphite/epoxy laminated composites. Multi-directional CLS specimens were used for fracture tests. The stacking sequences used for the lap and the strap were $[90_2/0_2]_s/[0_4/90_4]_s$ and $[0/\pm45/0]_s/[0_2/\pm45_2/0_2]_2$, respectively. For both cases, the fracture toughness determined from the work factor approach was compared with that determined from the compliance method. It was found that both methods produced fracture toughness within a maximum 15% difference for each stacking sequence. The fractography analysis also showed that the fiber bridging occurred for$[0/\pm45/0]_s/[0_2/\pm45_2/0_2]_2$ case while it did not occur for $[90_2/0_2]_s/[0_4/90_4]_s$ case.

• 한국산학기술학회논문지
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• 제7권1호
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• pp.89-95
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• 2006

공급사슬망에서 분산되어있는 제조시스템에 대한 생산 계획수립은 공급사슬관리의 주요 연구분야 중의 하나이다. 본 논문은 공급사슬망에서 자원제약을 갖는 다단계 다품목 로트사이즈 결정 문제(Multi-Level, multi-item Capacitated Lot Sizing Problem: MLCLSP)를 위한 알고리즘을 제시한다. MLCLSP는 MIP(mixed integer program) 문제에 해당한다. 제안된 알고리즘은 휴리스틱과 최적화 패키지인 LINGO를 이용해 서로 반복적인 방식으로 해를 풀어나가는 혼성적인 성격을 갖는다. 휴리스틱을 이용하여 정수형 변수를 결정한 후, 얻게 되는 LP(linear program) 문제를 LINGO를 이용하여 해를 개선해 나가는 방식을 기본으로 한다. 본 논문에서는 탐색 휴리스틱 기법으로 임의 재시작 타부탐색 알고리즘을 제시한다. 다양한 시나리오의 실험을 통해 제안된 알고리즘들의 성능을 평가한다.

• 제어로봇시스템학회논문지
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• 제19권9호
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• pp.846-852
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• 2013

In this paper, the authors propose a new approach to control problem of the marine vessels which are moored or controlled by actuators. The vessel control problem in the specified area is called a DPS (Dynamic Positioning System). The main objective of this paper is to obtain more useful control design method for DPS. In this problem, a complicate fact is control allocation which is a numerical method for distributing the control signal to the controlled system. For this, many results have been given and verified by other researchers using two individual processes. It means that the controller design and control allocation design process are carried out individually. In this paper, the authors give more sophisticated design solution on this issue. In which the controller design and control allocation problem are unified by a robust controller design problem. In other word, the stability of the closed-loop system, control performance and allocation problem are unified by an LMI (Linear Matrix Inequality) constraint based on $H_2/H_{\infty}$ mixed design framework. The usefulness of proposed approach is verified by simulation with a supply vessel model and found works well.

• Asia pacific journal of information systems
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• 제32권1호
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• pp.92-124
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• 2022

Providing services using kiosks is actively carried out between suppliers and consumers. These service processes have recently begun to play a dominant role in transactions. However, previous self-service technology (SST) studies or kiosks have not fully reflected the changing environment surrounding these different technologies. To cover the updated business environments, we combined qualitative and quantitative research methods. Through qualitative research and a review of previous studies, the variables emphasized as motivations and constraints for kiosks use and those that can be newly illuminated were selected for this study. We then applied the variables to the research model to assess their influence. In terms of the motivations for using kiosks, the results suggest that perceived usefulness and compatibility as service quality, forced use, and perceived service providers' efficiency as provider polices, absorptive capacity, and habit as an individual characteristic and social influence as a subjective norm have a significant effect on the attitude toward kiosks. In terms of constraints, difficult to use and need for interaction predicts the attitude toward kiosks. Attitude toward kiosks, perceived behavioral control, and social influence are directly related to the intention to use kiosks. Lastly, intention to use kiosks plays a significant role as an antecedent of revisit intention. Using these empirical results, we propose both academic and practical implications for future kiosks use.

• Asia pacific journal of information systems
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• 제33권3호
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• pp.541-572
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• 2023

Amazon Go is a cashierless convenience store concept, which is seen as a disruption in the grocery retail segment. Although Amazon Go has the ability to disrupt the retail segment, there are speculations on how Amazon Go will be perceived by users. Existing studies have not utilized user-generated content to understand the factors that affect customer behaviour in case of Amazon Go. Additionally, in case of phygital retail, studies have not attempted at understanding the effect of emotions and gratifications on user behaviour. To address the gap of exploring user perspectives based on their experience, we have examined the impact of gratifications and emotions on the acceptance of phygital retail using user-generated-content. A mixed-method approach has been utilized using only user-generated content. Utilizing topic-modelling based content analysis and emotion analysis on 30 articles related to Amazon Go, we found themes like, convenience, technology, experience, personalization, enjoyment and emotions like, bad, good, annoyance, success. In the empirical analysis, we have utilized 522 reviews about Amazon Go from the cognition and emotion theory stance, and found that hedonic gratifications have a positive impact on challenge emotions. We also found a significant impact of emotions on customer's favourite behaviour.

• 인터넷정보학회논문지
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• 제14권5호
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• pp.49-57
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• 2013

본 연구에서는 효율적인 온 라인 문서 자동 분류를 위해 매우 중요한 분류 작업의 전처리 단계인 특징선택을 위한 새로운 방법이 제안된다. 대부분의 기존 특징선택 방법 연구에서는 특징 집합의 모집단이 단일 모집단으로써 한 모집단이 가지는 정보만으로 분류에 적합한 특징들을 선택하여 특징 집합을 구성하였다. 본 연구에서는 단일 모집단에 한하여 수행되는 특징선택 뿐 만 아니라, 다중 모집단을 가지는 혼합 특징 집합에 대해서 특징선택을 함으로써 다양한 정보를 바탕으로 한 특징 집합을 구성하였다. 혼합 특징 집합은 두 종류의 특징 집합으로 구성된다. 즉 각각 문서로부터 추출한 단어로 구성된 원본 특징 집합과 원본 특징 집합으로부터 LSA를 이용하여 새로 생성한 변형 특징 집합이다. 혼합 특징 집합으로부터 필터 방법과 래퍼 방법을 이용한 하이브리드 방식의 특징 선택을 통해 최적의 특징 집합을 찾고, 이를 이용하여 문서 분류 실험을 수행하였다. 다양한 모집단의 특징들의 정보를 모두 고려함으로써 보다 향상된 분류 성능을 보일 것이라고 기대하였고, 인터넷 뉴스 기사를 대상으로 분류 실험한 결과 90% 이상의 향상된 분류성능을 확인하였다. 특히, 재현율과 정밀도 모두 90%이상의 성능을 보였으며, 둘 사이의 편차가 낮은 것을 확인하였다.

• 산업공학
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• 제17권3호
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• pp.282-293
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• 2004

Line Balancing is the problem to assign tasks to stations while satisfying some managerial viewpoints. Most researches about the Mixed-Model Line Balancing problems are focused on the minimizing the total processing time or the number of workstations. Independently, some research reports consider the balance issues of the physical workloads on the assembly line. In this paper, we are presenting a new mathematical model to accomplish the line balance considering both the processing time and the workloads at the same time. To this, end, we propose an zero-one integer program problem, and we use the Chebyshev Goal Programming approach as the solution method. Some computational test runs are performed to compare the pay-offs between the processing time and the workloads. And, the test results show us that the reliable balanced work schedules can be obtained through the proposed model.

• 응용통계연구
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• 제27권2호
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• pp.263-275
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• 2014

본 연구에서는 비동차 마코프 체인에서 개체들의 전이 행태를 분석하기 위한 계층적 베이지안 방법론을 사용하여 혼합 효과 모델을 소개 하였다. 모델의 모수들에 대한 사후분포가 분석적으로 구해질 수 없는 형태를 가지기 때문에 깁스(Gibbs) 샘플링 시뮬레이션 방법을 사용하여 조건부 사후확률로부터 샘플이 추출되었고, 실제 자료분석을 예를 사용하였다.