• Journal of Internet Computing and Services
• /
• v.7 no.3
• /
• pp.133-142
• /
• 2006

The purpose of the multiple key agreement protocol is to get efficiency in computational and communicational aspects compared to multiple executions of single key agreement protocol. However ID based tripartite multiple key agreement protocols have been proposed, it is reported that they can not resist unknown key-share attack or impersonation attack. How to design a secure and efficient ID-based authenticated tripartite multiple key agreement scheme to prevent all kinds of attacks remains an open problem. This paper proposes a multiple key agreement scheme combing the existing single key agreement protocol with a key derivation function. The proposed scheme can not only increase computational efficiency compared to the existing multiple key agreement protocol, but can ensure security of the proposed schemes by using a security proofed single key agreement protocol and key derivation function.

• Proceedings of the Korea Institute of Convergence Signal Processing
• /
• 2003.06a
• /
• pp.38-41
• /
• 2003

There are many kinds of algorithms used for the purpose of data mining. But without the understanding the underlying principles in the algorithm, the result of the data mining cannot be interpreted correctly. In this paper, the principle of ID3 algorithm is explained for that purpose. In addition, the way how to generate good training examples from the relational database is treated, as well as how to convert continuous values into discrete values is considered to use the algorithm for the data mining of real world database.

• Proceedings of the Korean Information Science Society Conference
• /
• 2005.07b
• /
• pp.625-627
• /
• 2005

결정 트리(Decision Tree)는 주어진 데이터의 경향을 학습하는 데 사용되는 대표적인 방식이다. 이것은 주어진 데이터를 구조화하기 위하여 데이터의 속성과 정보의 엔트로피에 기반을 둔 정보획득량을 이용한다. 본 논문에서는 유비쿼터스 환경에서 사용자 프로파일 정보처럼 시간에 따라 그 경향이 변하는 데이터에 유용하게 적용할 수 있는 시간 가중치 엔트로피를 정의한다. 그리고 ID3 알고리즘을 기반으로 새롭게 제안하는 시간 가중치 엔트로피를 이용하는 향상된 ID3 알고리즘을 쓰고 사용자의 경향을 분석한다. 본 논문에서 제안하는 엔트로피를 이용하는 방식은 데이터들의 시간에 관한 영향을 고려해서 기준방식보다 분석결과가 더욱 유리하다. 두 방식의 비교 테스트 결과를 보면 시간 가중치 엔트로피를 이용하는 알고리즘은 기존의 ID3 알고리즘보다 구성된 트리의 구조가 매우 간단하고 유리하다.

• Korean Journal of Food Science and Technology
• /
• v.48 no.4
• /
• pp.384-391
• /
• 2016

In previous studies, we confirmed that the ethanol extract of Polygonatum sibiricum (ID1216) has anti-obesity effects on high-fat diet-fed mice. To identify the obesity-related genes affected by ID1216, we studied its effects both in vivo and in vitro. In mice, single administration of ID1216 increased the expression of obesity-related genes including sirtuin1 (SIRT1), peroxisome proliferator-activated receptor ${\gamma}$ coactivator $1{\alpha}$ ($PGC1{\alpha}$) and peroxisome proliferator-activated receptor ${\alpha}$ ($PPAR{\alpha}$) compared to that in mice administered the vehicle; their downstream genes (uncoupling proteins, acyl-CoA oxidase, adipocyte protein 2, and hormone-sensitive lipase) were also increased by ID1216. In fully differentiated 3T3-L1 adipocytes, ID1216 showed the same effects on anti-obesity genes as those in the animal model. Based on these results, we propose that ID1216 has anti-obesity effects by regulating the $SIRT1-PGC1{\alpha}-PPAR{\alpha}$ pathway and their downstream genes, thereby controlling energy and lipid metabolisms.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.13 no.3
• /
• pp.53-64
• /
• 2017

Korean Identification card or driver license is usually used to verify one's identity in Korea. These are also used as an adult certification. Since the form of these ID card is an analog and it needs to be checked with naked eyes, it might be used maliciously. Someone who's got someone else's ID card can do other things. Therefore, it must be reported rapidly when ID card is lost or stolen. The most serious problem might be occurred when they do not recognize and report the loss. They might suffer from pecuniary or mental damage such as opening a mobile phone service, providing loan or credit card, opening a personal checking account, etc. Thus, this study suggests and compares the ways of avoiding these problems. First, the most effective way is to send the authorization code via mobile phones in consideration of build-up period and cost. The person in charge of business processing department using ID card sends the authorization code via registered mobile phone. The owners submits it to the person and their identifications are confirmed. Next effective way is that the person in charge of business processing department using ID card sends text messages via registered mobile phone. Lastly, the most ineffective way is to introduce and implement the electronic ID card ultimately even though it is expensive and takes a long time to build up the system.

• Convergence Security Journal
• /
• v.20 no.3
• /
• pp.29-37
• /
• 2020

Password based authentication technology is yet certain and id to provide a level of security being used in most systems, but already a myriad of personal information exposure to the accident. Above all, and once exposed, it is difficult to recover the password. Thus, the various authentication techniques - factor two was introduced, but they are expensive and discomfort to users, to lead. In this paper, the existing unique to users in such a single accreditation process / password id key - stroke, user authentication and cost effectively and at the same time. And not cause discomfort, suggested technologies that can also ensure high security exposure, password id. This paper's proposals and determine the effectiveness of the system to build model.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.18 no.6 s.121
• /
• pp.664-673
• /
• 2007

In this paper, the ID-FDTD scheme, proposed in Reference [1] and [2], is modified and completely analyzed. The modifications are composed of three parts: rigorous stability analysis, dispersion relation for linear lossy media, and new scaling factors for permittivity, permeability, and conductivity. As a result, it is shown that the proposed scheme has lower dispersion error in spite of larger time step than the conventional standard scheme of Reference [3]. To validate the scheme, there are presented two scattering examples, which show excellent results.

• Journal of Advanced Marine Engineering and Technology
• /
• v.31 no.3
• /
• pp.224-234
• /
• 2007

Large diameter tubes have been used until comparatively lately. However, small diameter tubes are largely used because of their high efficiency in heat transfer and low cost, recently. This study focuses on the experimental research of the heat transfer coefficients during evaporation process of R-22 and R-134a in small diameter tubes. The evaporation heat transfer coefficients were measured in smooth horizontal copper tubes with ID 1.77, 3.36 and 5.35 mm. The evaporation heat transfer coefficients in the small diameter tubes (ID <7 mm) were observed to be strongly affected by the size of tube diameters and to differ from those of general predictions in the large diameter tubes. The heat transfer coefficients of ID 1.77 mm copper tube were higher by 20 and 30 % than those of ID 3.36 mm, ID 5.35 mm copper tubes respectively. Also, it was found that it was very difficult to apply some well-known previous predictions (Shah's, Jung's. Kandlikar's and Oh-Katsuda's correlation) to small diameter tubes. Based on the data, the new correlation is proposed to predict the evaporation heat transfer coefficients of R-22 and R-134a in small diameter tubes.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.4
• /
• pp.560-567
• /
• 1996

The present study was undertaken to evaluate the effect of indigestible dextrin on bowel function and serum lipid. Recently developed indigestible dextrin is water soluble dietary fiber obtained by heating and enzyme-treatment of potato starch with low viscosity. SD male rats weighing 80~85g were divided into three groups; control diet(IC), control +5% pectin(IP), control +5% indigestible dextin(ID). Experimental rats were fed one of the experimental diets ad libitum for six weeks. Weight gain, food intake, and food efficiency ratio were not significantly different among other groups. Those of ID tended to be higher than in IP and IC. Weights of liver, spleen and kidney were not significantly different among groups. Epididymal fat pads weight in W and ID tended to be lower than in IC. The weight of cecum was sinificantly higher in m than in other groups(p<0.05). The weight and length of large intestine tended to be higher in IP and ID than in IC. Total feces excretion of ID and If tended to be more than that of IC. Transit time was shorter in IP than in other groups. Serum total lipid, total cholesterol and TG levels were higher in IC group than other groups. The fecal excretion of lipid was significantly higher in IP than in other groups(p<0.05). That of ID tended to be more than that of IC, so fat apparent absorption of ID was lower than that of IC. Ca absorption were decreased more in IP than in other groups(p<0.05).

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.21 no.2
• /
• pp.322-332
• /
• 2017

Wireless Body Area Networks is an environment that provides an appropriate service remotely by collecting user's biometric information. With the growing importance of sensor, WBAN also attracts extensive attention. Since WBAN is representatively used in the medical field, it can be directly related to the patient's life. Hence security is very important in WBAN. Mutual authentication between the client and the application provider is essential. And efficiency is also important because a used device is limited to computation cost. In this reason, ID-based anonymous authentication scheme in WBAN has been intensively studied. We show that the recent research result of Wu et al. which is about the ID-based anonymous authentication scheme is vulnerable to impersonation attack. And we propose a new ID-based anonymous authentication scheme that is secure against the attacks discovered in the existing schemes. Compared to the existing schemes, the computation cost of our scheme is improved by 30.6% and 7.3%.