• Transactions of the Korean hydrogen and new energy society
• /
• v.23 no.1
• /
• pp.65-72
• /
• 2012

Rankine cycle using ammonia-water mixture as a working fluid has attracted much attention, since it may be a very useful device to extract power from low-temperature heat source. In this work, the thermodynamic performance of regenerative ammonia-water Rankine cycle is thoroughly investigated based on the second law of thermodynamics and exergy analysis, when the energy source is low-temperature heat source in the form of sensible energy. In analyzing the power cycle, several key system parameters such as ammonia mass concentration in the mixture and turbine inlet pressure are studied to examine their effects on the system performance including exergy destructions or anergies of system components, efficiencies based on the first and second laws of thermodynamics. The results show that as the ammonia concentration increases, exergy exhaust increases but exergy destruction at the heat exchanger increases. The second-law efficiency has an optimum value with respect to the ammonia concentration.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.387-390
• /
• 1996

In this paper, A new PI-type reaching law for variable structure control is proposed to alleviate the chattering and improve the robustness properties in the presence of matched uncertainty. The proposed reaching law consists of a proportional term and an integral term. And the dynamics of switching function can easily be specified by using the second-order system analysis method. And also the proposed scheme has the advantages of alleviating the chattering than Gao's one and reducing the influence of uncertainties by band pass filter characteristic. The efficiency of the proposed method has been demonstrated by simulations for Dutch Roll damping in a light aircraft.

• Proceedings of the Korean Society for Language and Information Conference
• /
• 2002.02a
• /
• pp.411-420
• /
• 2002

The left-associative grammar model (LAG) has been applied successfully to the morphologic and syntactic analysis of various european and asian languages. The algebraic definition of the LAG is very well suited for the application to natural language processing as it inherently obeys de Saussure's second law (de Saussure, 1913, p. 103) on the linear nature of language, which phrase-structure grammar (PSG) and categorial grammar (CG) do not. This paper describes the so-called Loom-LAGs (LLAG) -a specialization of LAGs for the analysis of natural language. Whereas the only means of language-independent abstraction in ordinary LAG is the principle of possible continuations, LLAGs introduce a set of more detailed language-independent generalizations that form the so-called loom of a Loom-LAG. Every LLAG uses the very smut loom and adds the language-specific information in the form of a declarative description of the language -much like an ancient mechanised Jacquard-loom would take a program-card providing the specific pattern for the cloth to be woven. The linguistic information is formulated declaratively in so-called syntax plans that describe the sequential structure of clauses and phrases. This approach introduces the explicit notion of phrases and sentence structure to LAG without violating de Saussure's second law iud without leaving the ground of the original algebraic definition of LAG, LLAGS can in fact be shown to be just a notational variant of LAG -but one that is much better suited for the manual development of syntax grammars for the robust analysis of free texts.

• Journal of Science and Technology Studies
• /
• v.3 no.1 s.5
• /
• pp.105-156
• /
• 2003

This paper aims to explore the cause and aspect of inter-ministerial policy conflict and its coordination in science and technology policy-making with the case of science and technology basic law-making process in Korea. This law-making processes are analysed through the three periods for the last 10 years starting 1992, such as law-formulation(1st) period, interim law-making (2nd) period, and final law-making(3rd) period. Based on these steps, it tries to concretely describe the phenomenon of policy conflict and the coordination mechanism among government departments and analyses the characteristics of dynamic interaction and mutual adjustment among the related agencies. The analysis is mainly focussed on the underlying causes and determinants of policy conflict, the development and coordination process of the conflict, the strategies and logics of the conflict participants, and eliciting some policy implications for effective policy coordination among government departments. Research results are summarized as follows. First, in science and technology policy-making the main causes of policy conflict among government departments are attributed to the difference of policy-orientation and jurisdiction-orientation of each agency. During the first period, the main aspect of policy conflict was policy-oriented, during the second, the main aspects of policy conflict were both policy-oriented and jurisdiction-oriented, and during the third, policy-oriented conflict was dominant. Second, the dominant typology and strategies of policy coordination which the participants used were vertical-political and horizontal-analytic approach. During the first period, horizontal and analytical approach were used, during the second, horizontal and political approach are mixedly used, and during the third, vertical and political approach were dominantly used. Third, The Korean National Assembly and the ruling party played a pivotal role in science and technology policy-making process(the basic law-making process) in particular during the final period.

• Korean Journal of Human Ecology
• /
• v.14 no.2
• /
• pp.251-268
• /
• 2005

This study analyzes the amendment history of Educare Law of Infants and Children, the Equal Employment Opportunity Law, and Employment Insurance Law, and also examines the present status of the employer-supported child care service through secondary analysis of other policy studies. The three laws concerning employer-supported child care can be said to hold in itself two main concepts: employers' obligations to provide child care, and government's financial support and administrative management. In terms of the first concept, laws have been amended to enlarge the number of enterprises legally-responsible for child care service and to relieve the financial burden from them. In terms of the second, laws have been amended to gradually extend the magnitude of government's financial support and to establish the systematic administrative management. Approximately a half of the policy target enterprises, however, is not complying the laws. In addition, employer-supported child care centers are only occupying less than 1% of the whole child care market. Thus, this study evaluates the current employer-supported child care service system and suggests several principles for its improvement.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.32
• /
• pp.29-56
• /
• 2006

This article primarily concerns the various aspects of the rules to control express terms particularly in standard form which seek to absolve either wholly or in part from the seller's liability for non-conforming goods. It describes and analyzes in detail how English law regulates such terms. In this analysis, it places the following questions; first, whether each jurisdiction treats the seller's liability for non-conformity in quality and quantity as mandatory rules, second, if it does, to what extent it is treated so and third, if not, in what way it controls the seller's attempt to exclude or restrict his liability for non-conformity in quality and quantity. In addition, it attempts to compare the rules under English law with those under Korean law and to evaluate them in light of the discipline of comparative law. In an attempt to evaluate them, it asks the question of whether a solution from one jurisdiction may facilitate the systematic development and reform of another jurisdiction. The evaluation is based upon the idea that the problems of fairness associated with the use of standard terms occur where the customer is unfairly taken by surprise due to his ignorance of the terms, or where even if he knows of the substance of the terms and objects to it, he is met with a take-it-or-leave-it situation.

• Journal of applied mathematics & informatics
• /
• v.41 no.3
• /
• pp.487-510
• /
• 2023

We propose a mathematical model which describes the frictional contact between a piezoelectric body and an electrically conductive foundation. The behavior of the material is described with a linearly electro-viscoelastic constitutive law with long term memory. The mechanical process is dynamic and the electrical conductivity coefficient depends on the total slip rate, the friction is modeled with Tresca's law which the friction bound depends on the total slip rate with taking into account the electrical conductivity of the foundation both. The main results of this paper concern the existence and uniqueness of the weak solution of the model; the proof is based on results for second order evolution variational inequalities with a time-dependent hemivariational inequality in Banach spaces.

• Journal of Engineering Education Research
• /
• v.24 no.6
• /
• pp.60-66
• /
• 2021

The paper aimed to analyze research trends and productivity, targeting papers published for the past 24 years in The Journal of Engineering Education Research, For the research trend analysis, the content analysis was conducted and research productivity of authors was investigated through Lotka's Law. The research subject were 897 papers published on The Journal of Engineering Education Research from 1998 to June 2021. Research findings are as follows. First, the pattern of writing showed that percentage of co-authors over 2 was higher than single author. Second, the authors were most likely to belong the university, followed by government agency, affiliated organization and Research institutes in universities. Third, the flow of records in giving paper showed that the number of continuants has decreased over time and only a few writers have presented their papers. Fourth, the analysis results on the research productivity discovered difference in actual figure and revised, theoretical one, which indicates that Lotka's Law was not applied to The Journal of Engineering Education Research. Based on findings as shown below, we suggested a series of plans to develop The Journal of Engineering Education Research and increase research productivity in future.

• Journal of the Korea Society of Computer and Information
• /
• v.24 no.6
• /
• pp.125-133
• /
• 2019

This study aimed to investigate the political system related to the Electronic Government Law by analyzing the process of the common initiative of the law. To achieve the goal, this study applied the method of social analysis and sugessted the proper role of the assembly for realizing the electronic government and its control. The data were gathered from the bill information service of the national assembly. Netminer 4.0 was used for refining and analyzing data. The results are as follows. First, by analyzing three centrality(degree, betweenness, and eigenvector) of assembly member, the network effect of the powered party and reelected members were revealed as strong in the network. Second, through the component analysis, 5 sub-network has shown in total. The sub-networks showed two distinctive difference between two big parties. By the difference, members in two parties showed different characteristics in constituting communities and the effect of the powered party revealed as strong and clear. Based on the result, this study demonstrated the necessity of social solidarity rather than solipsism in committing common initiative. And a chronological research is need to anlayze $18^{th}$ and $19^{th}$ assembly to verify the effect of the powered party in prospect study.

• Journal of The Korean Association For Science Education
• /
• v.28 no.8
• /
• pp.796-813
• /
• 2008

A good understanding of how gifted science students understand physics is important to developing and delivering effective curriculum for gifted science students. This dissertation reports on a systematic investigation of gifted science students' reasoning model in learning physics. An analysis of videotaped class work, written work and interviews indicate that I will discuss the framework to characterize student reasoning. There are three main groups of students. The first group of gifted science students holds several different understandings of a single concept and apply them inconsistently to the tasks related to that concept. Most of these students hold the Aristotelian Model about Newton's second law. In this case, I define this reasoning model as the manifold model. The second group of gifted science students hold a unitary understanding of a single concept and apply it consistently to several tasks. Most of these students hold a Newtonian Model about Newton's second law. In this case, I define this reasoning model as the coherence model. Finally, some gifted science students have a manifold model with several different perceptions of a single concept and apply them inconsistently to tasks related to the concept. Most of these students hold the Aristotelian Model about Newton's second law. In this case, I define this reasoning model as the coherence model.