• Journal of Information Technology Applications and Management
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• v.21 no.3
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• pp.135-156
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• 2014

The Online business model for purchasing agent service is getting more popular. However, consumers perceive more risk when buying products from foreign online purchasing agents (FOPA) than from common online sellers (COS). This study focuses on finding out how consumers manage risk when they perceive risk and what different risk-reliever strategies they use when buying from high-risk FOPA and low-risk COS. This study has proved the following two. First, when consumers perceive risk at online purchasing, they tend to select risk-reliever strategies, such as the use of communication media, online assurance mark, seller's record, and secure payment to mitigate risk. With the application of those risk-reliever strategies, they built trust with the seller. Second, risk-perception of FOPA influences usage of communication media and check of online assurance mark more strongly than that of COS. On the contrary, risk-perception of COS influences the check of seller record more strongly than that of FOPA. This study helps to explain why FOPA is proliferating, despite its inherent high risk due to the fact that buyers and sellers are separated in time and space and that buyers and sellers have different social and cultural backgrounds. This study also helps managers of E-commerce to relieve consumer's risk-perception and to build trust.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2639-2641
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• 2000

계수적 구간 불확실 플랜트를 안정화하는 강인 제어기의 설계의 방법으로서 고정차수 극 배치(FOPA : Fixed Order Pole Assighnment) 알고리즘을 이용할 수 있다. FOPA 알고리즘에 의해서 강인제어기 계수의 집합은 선형제약조건으로 표현되고, 이 조건을 만족하는 임의의 한점은 주어진 불확실 시스템을 안정화한다. 본 논문에서는 선형제약조건으로 주어진 제어기 계수의 집합에서 외란의 에너지를 최소화하는 제어기를 구하는 알고리즘을 제안한다. 일반적으로 전역 최적해을 구하는 문제는 BMI(bilinear matrix inequalities)로 표현되지만 제어기의 계수를 고정했을 때는 LMI(lineal matrix inequalities)로 간략화되기 때문에 제어기계수에 대한 최소화와 성능지수에 대한 최소화를 반복함으로써 국부 최적해를 구할 수 있다. 제안한 알고리즘의 효용성을 보이기 위해 제어기 설계 예를 보이고, 그 성능을 비교 분석한다.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.1
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• pp.1-7
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• 2001

For a parametric uncertain system, there are many results on stability analysis, but only a few synthesis methods. In this paper, we proposed a new target polynomial decision method for the parametric uncertain system to stabilize the closed loop system with maximal parametric $l_2$ stability margin. To this, we used both Lipatov Theorem and coefficient diagram method(CDM). To show the effectiveness of the proposed method, we designed a robust controller for the inverted pendulum system with parametric uncertainties using fixed order pole assignment(FOPA) method and its performance was compared with that of the ${\mu}$ synthesis methods.

• Proceedings of the KIEE Conference
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• 1999.11c
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• pp.479-481
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• 1999

In this paper, We design low-order controller to achieve maximized controller stability margin and controller' Performance. FOPA(Fixed Order Pole Assignment) method is one of the approach to design controller in the parametric uncertain system. But the method to define a Target Polynomial is not explicit1y Known. In this paper, our goal is to find a controller Coefficient, such that performance and $l_2$ stability margin are maximized in the parametric uncertain system. Using Lipatove theorem and CDM(Coefficient Diagram Method), we set target polynomial constraints and design a controller which maximizes $l_2$ stability margin. we show effectiveness of the proposed controller design method by comparing $l_2$ stability many of the desired controller with that of the conventional robust controller.