• Proceedings of the Korean Information Science Society Conference
• /
• 2007.10d
• /
• pp.36-40
• /
• 2007

유비쿼터스 사회가 도래함에 따라 유비쿼터스 기술을 도시에 적용한 u-City가 개발되고 있다. u-City는 다양한 정보화 기기들이 존재하며 정보화 기기 사이를 연결하는 다양한 네트워크 기술이 상존한다. u-City의 핵심 요소인 uMC(ubiquitous Management Center)는 u-City 내의 모든 서비스를 처리하도록 설계되었으며 도시를 통제하는 중요한 기능을 수행한다. 따라서 사용자의 인증 및 보안을 처리하기 위한 기술이 요구되며 이러한 기술은 uMC에 필수적으로 구현되어야 한다. 본 논문에서는 기존의 인증 기술에 대해 설명하고, u-City 네트워크 환경에 적합한 인증 방법과 절차를 제안한다. 제안된 u-City 통합 인증 시스템은 u-City에 존재하는 정보화 단말기와 사용자를 인증하여 정당한 사용자에게만 IP를 할당하고, 할당된 사용자에 대해 정책에 따라 차별화된 권한을 부여 할 수 있으며, 따라서 uMC의 보안에 중요한 역할을 한다.

• 한국IT서비스학회:학술대회논문집
• /
• 2009.05a
• /
• pp.18-23
• /
• 2009

정부 주도적으로 전국적으로 U-City 구축이 확산되고 있으며 특히 신도시형 U-City 사업은 동탄 U-City가 완공됨에 따라 본격적인 운영단계에 접어들고 있다. 그러나 신도시형 U-City 사업은 이원화된 사업 수행 체계로 인한 많은 문제점들이 드러나고 있다. 본 논문에서는 U-City 사업의 가치사슬을 분석하여 문제점을 도출하고 이에 대한 해결방안으로서 U-City 거버넌스 모델을 제시하고 있다. U-City 거버넌스 모델은 구축뿐만 아니라 운영 단계까지 포함한 U-City 라이프사이클을 효율적이며 효과적으로 관리할 수 있는 조직 체계를 정의한다. 이와 같은 U-City 거버넌스 모델은 국내 U-City 사업뿐만 아니라 도시수출의 성과를 극대화 할 수 있는 기반을 제공할 것으로 기대된다.

• Journal of applied mathematics & informatics
• /
• v.23 no.1_2
• /
• pp.471-477
• /
• 2007

In this paper we establish some recurrence relations satisfied by the quotient moments of the upper record values from the Weibull distribution. Suppose $X{\in}WEI({\lambda})\;then\;E(\frac {X^\tau_U(m)} {X^{s+1}_{U(n)}})=\frac{1}{(s-\lambda+1)}E(\frac {X^\tau_U(m)}{X^{s-\lambda+1}_{U(n-1)}})-\frac{1}{(s-\lambda+1)}+E(\frac{X^\tau_U(m)}{X^{s-\lambda+1}_{U(n)}})\;and\;E(\frac {X^{\tau+1}_{U(m)}}{X^s_{U(n)}})=\frac{1}{(r+\lambda+1)}E(\frac{X^{\tau+\lambda+1}_{U(m)}}{X^s_{U(n-1)}})-\frac{1}{(\tau+\lambda+1)}E(\frac{X^{\tau+\lambda+1}_{U(m-1)}}{X^s_{U(n-1)}})$.

• American Studies
• /
• v.42 no.1
• /
• pp.57-97
• /
• 2019

This study seeks to reveal why the U.S. House Democrats showed different levels of support in the voting of the U.S.-Morocco FTA, U.S.-Bahrain FTA, and U.S.-Oman FTA. Existing studies focusing on the constituency or members' ideology do not properly account for the variance of these three FTA voting results. All of these FTAs, however, were promoted as a part of the president's foreign policies. If so, FTA support in Congress could depend on representatives' evaluation of the presidential foreign policy. Based on this, the study analyzes how representatives' evaluation of President Bush's foreign policy changed according to the period of the three FTA votes. The vote on the FTAs has been influenced by their evaluation of the presidential foreign and national security policies.

• Kyungpook Mathematical Journal
• /
• v.63 no.3
• /
• pp.333-344
• /
• 2023

In this paper, we generalize the notions uniformly S-flat, briefly u-S-flat, modules and dimensions. We introduce and study the notions of weak u-S-flat modules. An R-module M is said to be weak u-S-flat if Tor^R₁ (R/I, M) is u-S-torsion for any ideal I of R. This new class of modules will be used to characterize u-S-von Neumann regular rings. Hence, we introduce the weak u-S-flat dimensions of modules and rings. The relations between the introduced dimensions and other (classical) homological dimensions are discussed.

• Bulletin of the Korean Space Science Society
• /
• 1995.04a
• /
• pp.22-22
• /
• 1995

No Abstract. See Full-text

• Communications of the Korean Mathematical Society
• /
• v.38 no.1
• /
• pp.97-112
• /
• 2023

In this paper, we introduce and study the u-S-weak global dimension u-S-w.gl.dim(R) of a commutative ring R for some multiplicative subset S of R. Moreover, the u-S-weak global dimensions of factor rings and polynomial rings are investigated.

• Journal of Korean Society for Geospatial Information Science
• /
• v.23 no.2
• /
• pp.49-58
• /
• 2015

Up to the present point in time, the level diagnosis system for urban reactivation have utilized various methods for establishment and management in Korea and overseas, such as city competitiveness evaluation, urban decay diagnosis, etc. However, contrary to performing diagnosis and evaluations on general cities in existing studies, it is found to be a very complex and difficult task to perform a diagnosis on the level of U-City due to its unique characteristics. It is difficult to determine the level of a U-City using a level diagnosis system used for general cities because a U-City is comprised of a connection/fusion of various structural elements. Therefore, in order to perform a systematic diagnosis of a U-City, it is necessary to primarily observe the structural characteristics of a U-city to derive a diagnosis system based on the relativity between each structural element. This study aims to propose a directivity of a U-City level diagnosis system in comprehensive consideration of various elements, such as the objective of a U-City, as well as the structural elements that compose a U-City based on the definitions prescribed in U-City legislations, including ubiquitous city planning, ubiquitous city infrastructure, ubiquitous city technology, services, etc. The results of this study are expected to provide a resolution for the regional quality differences of U-Cities, and also establish a stepping-stone for the realization of U-Cities with high degree of completion.

• Current Research on Agriculture and Life Sciences
• /
• v.6
• /
• pp.171-180
• /
• 1988

Parathion is widely used in agriculture, but it is highly toxic and now clear that parathion behaves like a cholinergic drug by inhibiting the enzyme cholinesterase. In order to know the effect of toxicity and cholinesterase activity in rats injected repeatedly with parathion, cholinesterase activity in plasma, whole brain and spinal cord, and the subacute toxicity after repetitive intraperitoneal injection of parathion 20 times every 3 days were investigated. The results obtained were summerized as follows ; $LD_{50}$ value of parathion given intraperitoneally to rats was 10.5mg/kg(95% confidence limits, 6.6-16.8mg/kg). In subacute toxicity test of parathion injected intraperitoneally, mortality of parathion-pretreated rats(B : 57%, C : 83%) were increased in comparison with the control(50%). Cholinesterase activities in plasma of parathion-pretreated rats(B : 0.47 U/ml, C : 0.36 U/ml, AA : 0.31 U/ml, B : 0.26 U/ml, CC : 0.17 U/ml) were significantly decreased in comparison with the control(0.58 U/ml). Cholinesterase activities in spinal cord of parathion-pretreated rats(B : 1.87 U/g, C : 1.29 U/g, AA : 1.27 U/g, BB : 0.71 U/g, CC : 0.25 U/g) were decreased in comparison with the control(2.48 U/g). Cholinesterase activities in whole brain of parathion-pretreated rats(B : 2.52 U/g, C : 1.32 U/g, AA : 2.48 U/g, BB : 1.08 U/g, CC : 0.51 U/g) were significantly inhibited in comparison with the control(4.67 U/g). However, there were no differences in the urea nitrogen and creatinine concentrations between parathion-pretreated rats and control.

• Journal of Digital Convergence
• /
• v.10 no.2
• /
• pp.153-159
• /
• 2012

Now a days, U-healthcare comes into the spotlight as a new business model which combines RFID technology with medical service in the well-being era and IT popularization. U-healthcare service needs a method that can deals with hand-writing, overlap data, forgery and falsification of data, difference between information version that happen in medical process because of graft between RFID technology and u-healthcare. This paper proposes RFID based user certification protocol to protect user's privacy who gets medical service through U-healthcare. In the protocol, secret information of patient does the XOR with the secret key that is created in the hospital to reconsider the stability of security system of U-healthcare and user's data forgery and falsification and privacy and then saves it in the secret key field of patient in DB table. Also, it informs the case of illegal access to certification server and make it approved the access of u-healthcare service by differentiating whether u-healthcare is illegal or not.