• Corrosion Science and Technology
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• v.11 no.3
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• pp.77-81
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• 2012

Cathodic protection(CP) is widely used as a means of protecting corrosion for not only marine structures like ship hulls and offshore drilling facilities, but also underground structures like buried pipelines and oil storage tanks. The principle of CP is that the anodic dissolution of metal can be protected by supplying electrons to the cathode metal. When unprotected structures are nearby to CP systems, interference problems between unprotected and protected structures may be happened. The stray current interference can accelerate the corrosion of nearby structures. So far many efforts have been made to reduce the interference in the electric railway systems adjacent to the underground metal structures like buried pipelines and gas/oil tanks. During recent few decades the protection technologies against stray current induced corrosion have been significantly improved and a number of techniques have been developed. However, there is very limited information an marine environments. Some complex harbor structures are protected by two cathodic protection systems, i.e. sacrificial anode cathodic protection(SACP) and impressed current cathodic protection(ICCP). In this case, when the protection current from sacrificial anodes returns to the cathode through electrolyte, it passes through nearby other low resistance metal structures. In many cases the stray current of ICCP systems influences the function of SACP. In this study, the risk of stray current from the SACP system to adjacent reinforced concrete structures has been verified through laboratory experiments. Concrete and steel pile structures modeled a part of bridge have been investigated in terms of CP potential and current between the two. The variation of stray current according to the magnitude of ICCP/SACP has been studied to mitigate it and to suggest the proper protection criteria.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.711-713
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• 2001

MCCB(Molded Case Circuit Breakers) is a multi-function safety device which, unlike other forms of protection, combines many protection features in a single unit. This paper is the analysis of magnetic repulsion forces with the breaking current 11.28kA, 22.5kA, 38.9kA and 45kA.

• Journal of the Chungcheong Mathematical Society
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• v.5 no.1
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• pp.87-97
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• 1992

Sequential procedure with ${\beta}$-protection for the mean vector ${\mu}(\theta)$ of a p(> 1)-variate multivariate distribution $P_{\theta}$, ${\theta}{\in}{\Theta}$, with covariance matrix ${\sum}(\theta)$ is considered when the only nuisance parameters is ${\sum}(\theta)$. We obtain a confidence set for ${\mu}(\theta)$ with coverage probability condition and ${\beta}$-protection at ${\mu}-{\delta}(\mu)$ for some imprecision function ${\delta}:\mathbb{R}^p{\rightarrow}\mathbb{R}^p$.

• Proceedings of the Korean Information Science Society Conference
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• 2004.10a
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• pp.334-336
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• 2004

국내 전자상거래 제품과의 호환성과 확장성을 위하여 국내 전자서명 표준인 KCDSA(Korean Certificate-based Digital Signature Algorithm) 메커니즘을 PKCS(Public Key Cryptographic Standard) #11 암호 API(Application Programming Interface)에 기능을 추가한다. PKCS #11에서 정의한 키 관리(Hey Management) 함수의 입력 파라미터에 암호화할 키를 바로 입력하면 변조된 키를 전달할 수 있으므로, 본 논문에서는 안전한 키보호(Key Protection) 함수를 새로 정의하여 암호화할 키 대신 사용자 PIN(Personal Identification Number: 패스워드) 입력하여 사용자의 KCDSA 개인키와 공개키를 보다 더 안전하게 보관하고자 한다.

• Safety and Health at Work
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• v.12 no.1
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• pp.133-135
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• 2021

The COVID-19 pandemic has resulted in movement restrictions being instituted globally and the cessation of work at many workplaces. However, during this period, essential services such as healthcare, law enforcement, and critical production and supply chain operations have been required to continue to function. In Singapore, measures were put in place to protect the workers from infection at the workplace, as well as to preserve the operational capability of the essential service in a COVID-19 pandemic environment. This paper critically analyses the measures that were implemented and discusses the extension to broader general industry.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.23 no.1
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• pp.11-18
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• 2013

In order to prevent tampering and reverse engineering of executive code, this paper propose a new tamper resistant software mechanism. This paper presents a cryptographic MAC function and a relationship which has its security level derived by the importance of code block instead of by merely getting the encryption and decryption key from the previous block. In this paper, we propose a cryptographic MAC function which generates a dynamic MAC function key instead of the hash function as written in many other papers. In addition, we also propose a relationships having high, medium and low security levels. If any block is determined to have a high security level then that block will be encrypted by the key generated by the related medium security level block. The low security block will be untouched due to efficiency considerations. The MAC function having this dynamic key and block relationship will make analyzing executive code more difficult.

• Journal of Families and Better Life
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• v.10 no.2
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• pp.51-59
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• 1992

Previous studies indicated that unmarried persons are subject to higher mortality than the married, and that the differentials are more marked for male than for females. There are two major approaches to explaining the marital status differentials in mortality ; selection function and protection function of marriage. Following protection fucntion, this study develops the new "instrumental / expressive sex-role" hypothesis in order to explain why marriage protects males more against death. The hypothesis expects that male's instrumental role and female's expressive role have direct effect as well as indirect effect through social integration on sex differential mortality by marital status. for the hypothesis testing, Korea and US vital statistics and census data are used to compute age-specific , age-adjusted mortality rates and their ratios for persons in different marital status. Major findings are as follows. 1)For both Korea and US being married is more advantageous to males than females, ad being widowed, divorced, and separated is more disadvantageous to males, while being never-married is more disadvantageous to females, 2) For Korea, the never married men and women have the highest mortality rates, 3) For US the never married women have the highest mortality rate, while the divorced, separated, and widowed men have the highest mortality rate. Fro both Korea and US data, selection function is rejected, but instrumental/expressive sex-role hypothesis succeeds in accounting for the sex and marital status differential in mortality.

• Nuclear Engineering and Technology
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• v.45 no.4
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• pp.489-504
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• 2013

Software safety for nuclear reactor protection systems (RPSs) is the most important requirement for the obtainment of permission for operation and export from government authorities, which is why it should be managed with well-experienced software development processes. The RPS software is typically modeled with function block diagrams (FBDs) in the design phase, and then mechanically translated into C programs in the implementation phase, which is finally compiled into executable machine codes and loaded on RPS hardware - PLC (Programmable Logic Controller). Whereas C Compilers are fully-verified COTS (Commercial Off-The-Shelf) software, translators from FBDs to C programs are provided by PLC vendors. Long-term experience, experiments and simulations have validated their correctness and function safety. This paper proposes a behavior-preserving translation from FBD design to C implementation for RPS software. It includes two sets of translation algorithms and rules as well as a prototype translator. We used an example of RPS software in a Korean nuclear power plant to demonstrate the correctness and effectiveness of the proposed translation.

• Journal of Fashion Business
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• v.23 no.1
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• pp.1-13
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• 2019

This study aimed to analyze the preference, the factors of benefits sought, and the difference of benefits sought for smart clothing based on demographic characteristics. This survey study used questionnaire. The subjects of the survey consisted of men and women with ages ranging from twenty to fifty years old, who were living in Gyeongnam region. For the collected data analysis, Factor analysis, t-test, ANOVA, and Duncan multiple range tests were used by SPSS 23. The results obtained were as follows. The different analysis results for smart clothing based on demographic characteristics showed a significant difference with respect to marital status, age, monthly income, and occupation, but showed an insignificant difference with respect to gender. The factors of benefits sought for smart clothing were extracted from five factors-pursuit; image innovation and improvement, pursuit of healthcare, pursuit of body protection, pursuit of amusement and pleasure, and pursuit of hi-tech function. The different analysis results of smart clothing according to demographic characteristics showed a significant difference for pursuit of healthcare only with respect to gender, for pursuit of image innovation and improvement, healthcare, amusement and pleasure, and hi-tech function with respect to marital status, for pursuit of image innovation and improvement, healthcare, amusement and pleasure, and hi-tech function with respect to age, for pursuit of healthcare and body protection with respect to monthly income, and for all five factors with respect to occupation.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.4
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• pp.821-834
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• 2015

This study presents the analysis of flow and bed change characteristics considering bed protection work built on the immediate downstream of weir to protect river bed from scouring. The study area is 37km reach from Hyunpoong station to Masuwon station including Hapcheon- Changryoung multi-function weir in the Nakdong river. CCHE2D model is calibrated and validated for evaluating the flow and bed change characteristics during Typhoon Kompasu in 2010. Three simulation conditions are set up: Case 1 is a natural channel without installation of weir. Case 2 involves an installation of weir in the natural channel. Case 3 involves an installation of weir with bed protection in the natural channel. Flood frequency (50, 100 and 200yr) is applied to each scenario to analyze the effects of bed protection work. While the sediment rate is increased in the downstream of fixed gate and sluice-type gate, river bed scouring rate is increased in the downstream of lift-type gate in Case 2 comparing with the results of Case 1. The river bed scouring is not occurred in the immediate downstream of weir (~30m) due to the effect of bed protection, but larger amount of sediment is occurred in the downstream of weir (60m~) which the bed protection is not installed comparing with the results Case 1. Through the results of simulation considering bed protection work, this study would be helpful to expect bed change and operate the weir as well as manage.