• Journal of Korea Multimedia Society
• /
• v.2 no.2
• /
• pp.145-154
• /
• 1999

We are very interested in electronic commerce today, and it will is more developed in the future. In electronic commerce, we can easily purchase a cheap goods like digital data using a micropayment system. Though small value is used in micropayment system, it is important because it has many application. The transaction cost of a micropayment system must be small. Many protocols for the micropayment system are studied, but it's not support user's anonymity. In this paper, we examines the existing micropayment system and proposes a new micropayment protocol that have a anonymity.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.5B no.1
• /
• pp.27-33
• /
• 2005

The development of modern high-energy magnet materials has allowed the replacement of field coils in many different types of electromagnetic energy conversion machines. As well, the linear synchronous motor has recently been proposed for linear motion with high efficiency and thrust. Thus, this paper presents an analytical solution for the high thrust and cost reduction of the Iron-Cored Permanent Magnet Linear Synchronous Motor (PMLSM) considering magnetization arrays and geometry. Hence, the superior utilization points in each of the magnetization arrays are provided by the height ratio of the magnet/air-gap and magnet/winding coil, etc. In formulation, the space harmonic method in analytical solutions and the generalized 2-D tensor finite element analysis can be used to evaluate force components in magneto static devices including the magnetostrictive phenomenon.

• Proceedings of the KIEE Conference
• /
• 2005.07d
• /
• pp.2915-2917
• /
• 2005

본 논문에서는 개인 사용자가 쉽게 디지털 컨텐츠를 제작하여 다른 로컬 사용자의 계약에 의해 컨텐츠의 재분배까지 가능한 분산 거래 모델을 제시하였다. 제작되는 컨텐츠는 MPEG-21 멀티미디어 프레임워크를 기반으로 하여 컨텐츠에 관한 다양한 정보를 포함 할 수 있는 디지털 아이템 형식으로 제작되며, 본 논문에서는 개인 사용자가 쉽게 디지털 아이템을 제작할 수 있도록 DI(Digital Item)제작 tool을 구현하였다. 뿐만 아니라 컨텐츠 저작권 보호를 위해 MPEG-4 IPMP, REL을 이용하여 다양한 컨텐츠 관리 및 암호화 기능을 수행하는 소프트웨어를 구현하였고 이들을 기반으로 분산 거래 시스템을 구현하였다.

• Journal of Arbitration Studies
• /
• v.9 no.1
• /
• pp.323-365
• /
• 1999

The digital revolution is happening much more quickly and Internet Commerce and Electronic Commerce is having a profound influence on the global trade and internal commerce, revolutionize the way of doing business, especially retail and direct marketing. Owing to Internet, an increasing share of business transactions occurs online. Electronic payment is essential for the smooth progress of the electronic commerce as electronic payment plays the important role in the electronic commerce, that is, the value transfer resulting from the electronic commerce. So far, there have not been a considerable emphasis on the risks residing in the electronic payment and money. So, this paper deals with the risks in the electronic payment and money, in particular technical risks and social risks, and the reliability-increasing schemes to prevent the risks in the electronic payment. The reliability-increasing schemes relate to the security of the electronic payment systems and certification authority and key management, transaction rules between the parties concerned in the electronic payment.

• 한국디지털정책학회:학술대회논문집
• /
• 2004.05a
• /
• pp.719-731
• /
• 2004

2003 년에 정부에서 여러 가지 활동과 2004 년 1월에는 산업자원부에서 'e- Learning 산업발전법' 을 공표함으로써 e- Learning 산업의 앞날이 밝아오고 있다. 하지만 아직은 전통적인 교육보다 e-Learning이 일반적으로 성과나 만족도가 떨어진다는 연구가 지배적이다 [1, 17] 이러한 상황에서 e-Learning을 확산한다는 것은 매우 어렵다. 이것은 e-Learning을 경험하는 학습자들의 만족을 통하여 e-Learning의 확산을 촉진할 수 있는데, 이를 위하여 e-Learning 환경에서 학습자들이 어떠한 요인들로써 만족을 느낄 수 있는지 알아보아야 한다. 학습자의 특성에 따라 만족도에 미치는 요인들을 찾아내어 학습자의 특성에 맞게 관리를 해줌으로써 온라인 환경에서 학습자들을 효과적으로 관리할 수 있어야 한다.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.12B no.1
• /
• pp.31-36
• /
• 2002

In a switched reluctance motor drive, it is important to synchronize the stator phase excitation with the rotor position; therefore, the position of rotor is an essential information. Although optical encoders or resolvers are used to provide the position information, these sensors are expensive. Moreover, in the high-speed region, switching angles are fluctuated back and forth out of the preset value, which is caused by the sampling period of the microprocessor. In this paper, a low cost analog encoder suitable for practical applications is proposed. And the control algorithm to generate switching signals using a simple digital logic is presented. The validity of the proposed analog encoder with a proper logic controller is verified from the experiments.

• Journal of the Korea Computer Industry Society
• /
• v.2 no.9
• /
• pp.1233-1238
• /
• 2001

Security is very important at EC(Electronic Commerce) Environments. The reason is that exchanged data(that is user private information(accounts, card-no, password), transaction items, etc) is various and is very sensitive. In this paper, we propose the Secure-XML Messaging System(S-XMS) which is implemented to support Message Level Security, Encryption and Digital Signature. And we implement Message Confidentiality Service, User Authentication & Message Integrity Service and Non-Repudiation Service among the various Security Services.

• International Commerce and Information Review
• /
• v.7 no.3
• /
• pp.53-75
• /
• 2005

Owing to the Digital revolution, Internet Commerce and Electronic Commerce is having a profound influence on the global Market and internal commerce, revolutionizing the way of doing business. e-Marketplace have adopted in order to the reshape of the Fisheries Sector's competitiveness, and it is now being utilized as a major global marketing instrument to develop new customers, save Market transaction costs ad facilitate new work processes. The purpose of this study is to provide a program for activation in e-Marketplace of the Fisheries Sector in Gangwon Do. However, at present, the environment of e-Marketplace Infrastructure in Gangwon Do is very poor. Therefore, this study points out the problems of e-Marketplace of the Fisheries Sector in Gangwon Do and provides many considerations for a program for activation of e-Marketplace.

• Annual Conference of KIPS
• /
• 2005.05a
• /
• pp.1075-1078
• /
• 2005

The Global IT revolution is growing rapidly. Government and business have to be ready to meet the increased demand for effective and secure online services. With the E-Government practicing, day-by-day the public demand is also increasing simultaneously. Now this present moment, one of important research part is secure E-Voting for E-Government service, but for this important factor or Government Issue, it needs information privacy for secure information transaction of citizen’s opinions and secure authentication. This paper has analyzed several approaches E-voting protocols, those are implemented with many digital signature mechanism and maintained many types of cryptographic rules, which are main factor for information privacy. In this paper we have discussed them with a view to voter anonymity and protection from manipulations. The paper then developed an algorithm designed to guarantee anonymity of the voter and to avoid the risk of manipulation of votes. In this paper the proposed algorithm is based upon the strict separation of voter’s registration and submission of votes, which means that certain information has to be stored on a secure storage media.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
• /
• v.5B no.4
• /
• pp.312-316
• /
• 2005

The single phase induction motor has been commonly applied to small-sized electrical appliances because of its low cost, but it has low efficiency and large torque ripple, and it is incapable of speed control. However, two-phase induction motors have small torque ripple, high efficiency and variable speed control, because they are inverter fed. In this paper, the dynamic characteristics of the two-phase induction motor, such as the torque ripple, current and speed, are analyzed by using the time-stepping finite element method, and compared with the cage-type single phase induction motor.