• Journal of the Korean Society for Precision Engineering
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• v.21 no.8
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• pp.120-128
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• 2004

The impulse between launch vehicle and atmosphere can generate a lot of noise and vibration during the process of launching a satellite. Structurally, the electronic equipment of a satellite consists of an aluminum case containing PCB. Each PCB has resistors and IC. Noise and vibration of the wide frequency band are transferred to the inside of fairing, subsequently creating vibration of the electronic equipment of the satellite. In this situation, random vibration can cause malfunctioning of the electronic equipment of the device. Furthermore, when the frequency of random vibration meets with natural frequency of PCB, fatigue fracture may occur in the part of solder joint. The launching environment, thus, needs to be carefully considered when designing the electronic equipment of a satellite. In general, the safety of the electronic equipment is supposed to be related to the natural frequency, shapes of mode and dynamic deflection of PCB in the electronic equipment. Structural vibration analysis of PCB and its electronic components can be performed using either FEM or vibration test. In this study, the natural frequency and dynamic deflection of PCB are measured by FEM, and the safety of the electronic components of PCB is evaluated according to the results. This study presents a unique method for finite element modeling and analysis of PCB and its electronic components. The results of FEA are verified by vibration test. The method proposed herein may be applicable to various designs ranging from the electronic equipments of a satellite to home electronics.

• The Journal of Korean Society for School & Community Health Education
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• v.19 no.1
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• pp.1-11
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• 2018

Objectives: The purpose of this study is to provide basic data on the use of electronic cigarettes by identifying the relationship between smoking and smoking behavior and the use of electronic cigarettes. Methods: This study used data from 8,150 participants of the 'Korea National Health and Nutrition Examination Survey (KNHANES)' s 7th (2016). In this study, 1,051 people currently smoking were analyzed. The number of people using electronic cigarettes was 74 among current smokers. Results: The age of onset of smoking was 20.46 years old in the group not using electronic cigarette, and the age of starting smoking was 18.12 years old in the group using electronic cigarette(p<.001). In the education level, the current use of electronic cigarette was 1.82 times higher in high school graduates than college graduates(p<.005). The reason for using electronic cigarette was 4.32 times higher than other reasons for using electronic cigarette for the purpose of smoking cessation(p<.005). Conclusions: For the smoking cessation society, education for the electronic cigarette is needed from the adolescence and selective management for the people who use the electronic cigarette for the purpose of smoking cessation is needed.

• The Journal of Information Technology
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• v.3 no.1
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• pp.89-97
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• 2000

Electronic commerce on the network requires a new payment system, electronic cash that carries digitalized information of cash. The new system, however, demands the security and privacy because electronic cash is different from real cash in that it can be easily duplicated, forged, or traced. Therefore, electronic cash system should be guaranteed security and privacy to be used as a new payment mechanism with assurance. First, this paper analyzes the existing electronic cash system involving electronic coins, divisible electronic bills, and electronic license. Then the paper proposes a new electronic cash system which claims to be more efficient in the amount of communication and computation. Finally, this study attempts to solve the problem of electronic license.

• JSTS:Journal of Semiconductor Technology and Science
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• v.11 no.4
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• pp.329-335
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• 2011

In this paper, a dual-band integer-N frequency divider is proposed for 2.4/5.2 GHz multi-standard wireless local area networks. It consists of a multi-modulus imbalance phase switching prescaler and two all-stage programmable counters. It is able to provide dual-band operation with high resolution while maintaining a low power consumption. This frequency divider is integrated with a 5 GHz VCO for multi-standard applications. Measurement results show that the VCO with frequency divider can work at 5.2 GHz with a total power consumption of 22 mW.

• Journal of Magnetics
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• v.22 no.1
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• pp.49-54
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• 2017

The significant reduction of the image quality caused by the magnetic field of samples is a major problem affecting the application of SEM (scanning electron microscopy) in the analysis of electronic devices. The main reason for this is that the electron trajectory is deflected by the Lorentz force. The usual solution to this problem is degaussing the sample at high temperatures. However, due to the poor heat resistance of some electronic components, it is imperative to find a method that can reduce the impact of magnetic field on the image quality and is straightforward and easy to operate without destroying the sample. In this paper, the influence of different magnetic field directions on the imaging quality was discussed by combining the experiment and software simulation. The principle of the method was studied, and the best observation direction was obtained.

• Journal of Information Technology Applications and Management
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• v.10 no.3
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• pp.23-44
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• 2003

It is needed to search the electronic commerce standardization and to analysis its policies to meet the international situations strategically and forecast the technology surroundings for electronic commerce. This study aims at searching the current state of electronic commerce standardization and analyzing policies on electronic commerce by the driving subject, that is, government and private organization, major countries, and standard classifications of electronic commerce technologies such as e-documents, e-catalog, e-payment, and e-process. The government and private organizations get information for the current state and policies for standardization on electronic commerce and put them practical use to make policies and strategy applications.

• Journal of Information Technology Applications and Management
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• v.10 no.3
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• pp.93-108
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• 2003

As Electronic Commerce is popularized, crimes related to Electronic Commerce are also increasing, Electronic shopping malls and payment gateways focus their attention on network security of payment information or the sizes of encryption keys, In real world, however, the payment-related crimes in electronic shopping malls are not based on the security hole of encryption mechanism of the payment systems, but on the customers carelessness or the insecurity of server systems of merchants or financial institutes. So, this research analyzes the structure of current electronic payment systems, investigates the payment-related crimes, addresses the structural problems of the Korean electronic payment systems, and suggests an alternative general architecture for secure payment systems by incorporating the concept of separation of order information and payment information.

• The Journal of Society for e-Business Studies
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• v.4 no.2
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• pp.81-94
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• 1999

This paper shows the architecture of IPS(Intermarket Payment System), an implementation of the electronic payment function for internet-shopping merchant system. Because the original purpose of commerce transaction is the exchange of money for goods or services, it is very important to prepare an exchangeable economic value or method. The electronic payment system is the hardware or software or both to process an electronic payment transaction. It has two type, the broker type and the electronic value type. The broker type means an intermediator between real bank network and internet commerce transaction. The electronic value type means a substitute for money in the real world. This paper shows the architecture and the function to implement the broker type electronic payment system. The system has two parts. One is the mediator part to support multiple payment systems and to offer common access methods for merchant system database. The other is the executor part to implement the payment protocol and to process payment transaction.

• Journal of Digital Convergence
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• v.7 no.4
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• pp.11-19
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• 2009

Electronic methods are already used in money transfer and credit cards transactions and electronic money and checks, which can substitute cash and coins, are being discussed. Recently, the Acts of Electronic Draft have been enacted, in order to make the money in the market flow efficiently. Also electronic bill of lading has been adopted for the practical use of international shipments. However, despite of the effort from the academia and practice, investments to stocks, especially in the stock exchange, is not quite perfectly electronic. Japan enacted a relevant act in 2004 which make its stock market totally dematerialized. This writing summarizes some issues in interpretation that arise in the course of operation of the Stock Electronic Registration System at the present time of 6 months after it came into effect and its purpose, by doing so, is to prevent in advance the kind of problems in introducing the similar system to Korea.

• Korean Journal of Health Education and Promotion
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• v.30 no.5
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• pp.15-26
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• 2013

Objectives: To present the bases for health education on electronic cigarettes, we analyze the present state of electronic cigarettes. Methods: We applied descriptive study, reviewing the literature from domestic and foreign electronic databases such as National Discovery for Science Leaders and PubMed. Results: Electronic cigarette has been the subject of much controversy but very little study. I reviewed and summed up the definitions, device safety, health risk, smoking cessation effects, addiction, second hand smoke, and regulations of electronic cigarettes. Conclusion: Finally,I presented the evidence-based contents and desirable direction for health education about electronic cigarettes. The results suggested that the health educators focus on the potential addiction to electronic cigarettes, instead of the cessation effects.