• Journal of Welding and Joining
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• v.28 no.4
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• pp.18-25
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• 2010

Super-duplex stainless steels (SDSS) have a good balance of mechanical property and corrosion resistance when they consist of approximately equal amount of austenite and ferrite. The SDSS needs to avoid the detrimental phases such as sigma(${\sigma}$), chi(${\chi}$), secondary austenite(${\gamma}2$), chromium carbide & nitride and to maintain the ratio of ferrite & austenite phase as well known. However, the effects of the subsequent weld thermal cycle were seldom experimentally studied on the micro-structural variation of weldment & pitting corrosion property. Therefore, the present study investigated the effect of the subsequent thermal cycle on the change of weld microstructure and pitting corrosion property at $40^{\circ}C$. The thermal history of root side was measured experimentally and the change of microstructure of weld root & the weight loss by pitting corrosion test were observed as a function of the thermal cycle of each weld layer. The ferrite contents of root weld were reduced with the subsequent weld thermal cycles. The pitting corrosion was occurred in the weld root region in case of the all pitted specimen & in the middle weld layer in some cases. And the weight loss by pitting corrosion was increased in proportional to the time exposed at high temperature of the root weld and also by the decrease of ferrite content. The subsequent weld thermal cycles destroy the phase balance of ferrite & austenite at the root weld. Conclusively, It is thought that as the more subsequent welds were added, the more the phase balance of ferrite & austenite was deviated from equality, therefore the pitting corrosion property was deteriorated by galvanic effect of the two phases and the increase of 2nd phases & grain boundary energy.

• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.529-534
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• 2005

In this paper, a new type of output feedback control, called a $H_2/H_{\infty}$ fnite memory control (FMC), is proposed for deterministic state space systems. Constraints such as linearity, unbiasedness property, and finite memory structure with respect to an input and an output are required in advance to design $H_2/H_{\infty}$ FMC in addition to the performance criteria in both $H_2$ and $H_{\infty}$ sense. It is shown that $H_2$, $H_{\infty}$, and mixed $H_2/H_{\infty}$ FMC design problems can be converted into convex programming problems written in terms of linear matrix inequalities (LMIs) with some linear equality constraints. Through simulation study, it is illustrated that the proposed $H_2/H_{\infty}$ FMC is more robust against uncertainties and faster in convergence than the existing $H_2/H_{\infty}$ output feedback control schemes.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.253-255
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• 1999

In this paper, a shape optimization algorithm of superconducting magnet using finite element method is presented. Since the superconductor loses its superconductivity over the critical magnetic field and critical current density, this material property should be taken into account in the design process. Trial and error approach of repeating the change of the design variables costs much time and it sometimes does not guarantee an optimal design. This paper presents a systematic and efficient design algorithm for the superconducting magnet. We employ the sensitivity analysis based on finite element formulation. As for optimization algorithm, the inequality constraint for the superconducting state is removed by modifying the objective function and the nonlinear equality constraint of constant volume is satisfied by the gradient projection method. This design algorithm is applied to an optimal design problem of a solenoid air-cored superconducting magnet that has a design objective of the maximum energy storage.

• Communications of the Korean Mathematical Society
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• v.9 no.4
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• pp.961-973
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• 1994

A stochastics process $X = {X(t) : t \in T}$, with an index set T, is said to be infinitely divisible (ID) if its finite dimensional distributions are all ID. An ID process X is said to be a stochastic integral process if $X = {X(t) : t \in T} =^D {\int f_td\Lambda : t \in T}$ where $f : T \times S \to R$ is a deterministic function and $\Lambda$ is an ID random measure on a $\delta$-ring S of subsets of an arbitrary non-empty set S with the property; there exists an increasing sequence ${S_n}$ of sets in S with $U_n S_n = S$. Here $=^D$ denotes equality in all finite dimensional distributions.

• Journal of the Korean Data and Information Science Society
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• v.26 no.4
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• pp.895-906
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• 2015

Nowadays, many people have much interest in health and quality of life. They can get information on foods known to have remedial value for certain illness from many healthcare experts on TV health related shows. Moreover, a lot of studies on these foods and their remedial value are consistently published. Thus, this study, on the ground that if we know prognosis of a certain disease in advance we can lead a better life without suffering from diseases, statistically analyzes specific students' responses to sub-health questionnaire. The analysis reveals that results of testing the equality of gender and 10 diagnosis indexes shows significant difference within 5% of significance level in 9 diagnosis indexes except for respiratory system. And the result of testing the equality of age and 10 diagnosis indexes indicates that there is no significant difference within 5% of significance level. In the study, students are divided into two age category. However, the age of 20s could be regarded as one category, which could be the reason why there is no significant difference.

• Journal of the Korean Society of Costume
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• v.61 no.8
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• pp.100-113
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• 2011

The earlier notion of feminism regarding gender equality was changed into that of Postfeminism because of gender differences. The idea of Postfeminism has been present since the 1980s but has been influenced by modern culture theories such as Postmodernism, Poststructuralism, Theory of Power and Discourse and Psychoanalysis. Various features of Postfeminism are found in the medieval warrior images of contemporary fashion. Warrior costumes were men's exclusive property in the medieval ages, but as it is introduced as women's wear in the 21st century, it shows us new fashion images which are constructed by gender deconstruction, differences and pastiche. In this regard, the purpose of this study is to examine a key characteristic of Postfeminism fashion. An article described the historical costumes of medieval warriors and refocused on the development processes of feminism and then conducted an analysis on formative characteristics and Postfeminism tendencies in contemporary women's wear from 2000 to 2011. The results were that materials such as metallic and flexible materials, monotonic and red colors and detailed patterns of armor were used to display forms of exaggeration and restraint. These elements fully and correctly expressed the image of a medieval warrior woman in contemporary fashion. Postfeminism fashion is constructed with feminine power, gendered identity, sensual elegance and a postmodern body. Postfeminism is the contemporary cultural icon and is continuously influencing modern fashion design in the 21st century in a positive and powerful way.

• The Korean Society of Law and Medicine
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• v.13 no.1
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• pp.295-329
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• 2012

A medical malpractice case requires special legal protection, considering its characteristics, such as seriousness and long term effects of its damages, medical information asymmetry between practitioners and patients, and difficulties in realization of liability. Taking the points above into consideration, Medical Malpractice Arbitration Act of 2012(MAA) has legislative intent to protect the rights of the injured from medical malpractice, while protecting the stability of medical practice by providing arbitration as an alternative dispute resolution. However, constitutional review is required for one new scheme of compensation for medical injuries during delivery, which is implemented in MAA of 2012, especially with regard to freedom to exercise occupation, property, equality under the Constitution. Two important aspects are 1. according to the law, absolute liability applies to compensation for damages during delivery without negligence of practitioners; and 2. the practitioner bears some portion of the cost, 30% in the law above. This article aims to analyze this new institution in various aspects of the Constitution, and, as a result, it does not comply with constitutional criteria.

• The Journal of the Korea Contents Association
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• v.20 no.3
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• pp.560-571
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• 2020

Essential urban services that protect citizens' lives and property such as firefighting, disaster and crime prevention, should be provided equally to all citizens regardless of their location, personal status, and income. This paper analyzes the equality of firefighting services in spatial and social perspective in Daejeon Metropolitan City. For this the accessibility of fire service was analyzed for all settlements in the city. In addition, the distribution status of low-income class and forecasted income each region were compared to analyze whether the area where fire fighting service in 5 minutes was related to the distribution of income class. According to the analysis, the area where fire service can be provided within 5 minutes was 46.2% of Daejeon, and 98.0% of the population lived in this area. The proportion of old-age pensioners living in the area where fire service can't be provided within 5 minutes was 52.7%, reise than the average of 7.14% in Daejeon. In addition, in areas where the provision of firefighting services exceeds five minutes, the forecasted income tends to be lower in areas where service arrival is delayed. Therefore, it can be said that the economically vulnerable people living in the outskirts of Daejeon are not provided with equal urban services, and policy consideration is required accordingly.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.5
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• pp.1227-1236
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• 1993

In conventional thermodynamics, energy is regarded as a physical quantity transferring from one system to another, but in present study, the real energy is regarded as a physical quantity coming out from one interaction and absorbing into another interaction between two systems. To reconstruct thermodynamics with such a point of view, available work is distinguished from half work in conventional work concepts, and a special space named reversible world is proposed in which every process is reversible and the only measurable quantity is available work and just the equality between the intensities of two systems can be verified. As results, thermodynamic laws are arranged into two principles in the reversible world-conservations of energy elements and conservation of available energy. It means the exsistences of state properties corresponding to transferring energy elements and the available work. The former are extensive properties and the later is named potential work which is a property of the composite system and a kind of mathematical distance. The conventional available energy (exergy) and internal energy can be explained as the special cases of potential work, and the conventional first law of thermodynamics can be derived from the principle of the conservation of available energy. With these new concepts, the description of thermodynamic processes is more comprehensive. The second law of thermodynamics is no longer needed in the reversible world.

• Korean journal of communication and information
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• v.17
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• pp.7-36
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• 2001

This thesis discussed the nature of freedom of speech with emphasis on Locke's theory of social contract. First, I examined the nature of freedom of speech induced from Locke's social contract, and argued that the nature of Locke's freedom of speech exists on the self-ownership of humans. Secondly, I studied how Locke's right of self-ownership was related to the right of freedom of speech and how it is realized in civil society. I could analyze how freedom of speech was actualized with un-equality in the social relations. Thirdly, I investigated how locke's possessive freedom of speech was materialized in the market society. I tried to find out the nature of freedom of speech actualization in the capitalist market society. Finally, 1 studied to what extent the state of Locke could intervene the freedom of speech and reconsidered the meaning of locke's limit of natural risht in modern society. Conclusively, Locke's notion of Natural Right and Law of Nature have greatly influenced contemporary idea of free speech. His idea helps understand the position of liberal democratic speech. It also shows well the relation of freedom of speech and Natural Right and has helped us understand freedom of speech in terms of the position of the right of property.