• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.3
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• pp.749-761
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• 2014

Improving spectrum utilization efficiency is a fundamental goal of dynamic spectrum access technology. The definition of spectrum holes determines how to detect and exploit them. Current definitions of spectrum holes are ineffective in exploiting spatial-temporal spectrum holes. In this paper, a novel definition of spectrum holes is proposed, in which throughput loss indicates the impact of secondary users on primary users. The definition specifies spectrum holes, unifies the impact of secondary users on primary users and is effective exploiting spatial-temporal spectrum holes. Theoretical analysis and numerical simulations show that the new definition proposed in this paper significantly improves the spectrum utilization efficiency.

• Korean Journal of Child Studies
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• v.28 no.3
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• pp.219-233
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• 2007

The purpose of this study was to investigate university students' motivation for parenthood related to their definition of parenthood, empathy and self-esteem. Participants were 447 junior and senior students(male 263, female 184) in 5 universities throughout Korea. Results were : (1) Male students and employed mothers were higher than female students and unemployed mothers' 'motivation for strengthening biological family ties' but there were reversed results in 'motivation for traditional norms.' Students majoring in home economics showed the highest score in 'altruistic-emotional motivation.' (2) There were positive correlations between motivation for parenthood and definition of parenthood and empathy. 'Motivation for traditional norms' correlated positively with self-esteem. (3) Motivations for parenthood were explained by about 4~28% by their definition of parenthood, empathy, and self-esteem.

• Journal of Electrical Engineering and Technology
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• v.10 no.5
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• pp.1958-1968
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• 2015

In this paper, a new definition of short-circuit ratio concept for multi-converter HVDC systems is proposed. Analysis results of voltage interaction between converters show that the reactive power-voltage characteristic of a converter has a dominant effect on voltage interaction level compared with its active power-voltage characteristic. Such a relation between converter reactive power and voltage interaction level supports taking the former into account in the definition of short-circuit ratio concept for multi-converter systems. The proposed definition is verified by the method of maximum power curve for various system configurations. Furthermore, a formula to calculate transient overvoltage for multi-converter systems is derived based on the proposed definition, and the efficiency of the derived formula is verified.

• Journal of Information Technology Services
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• v.10 no.2
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• pp.309-327
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• 2011

Even though several methodologies for SOA(Service Oriented Architecture) have been proposed, in practical aspects most of them have some problems since they fail to propose specific policies in definition and identification of a service. This paper proposes a service modeling methodology. SOMO(Service Oriented Modeling using Ontology), which draws proper services in the process of defining and identifying services. SOMO defines a service ontology based on service definition and characteristics in SOA. The service drawing process consists of 3 steps : requirement analysis, service identification, and service definition. SOMO is expected to increase the degree of reuse and facilitates the definition and search of services by using service ontology. In addition, it clearly allows the definition and identification of services, satisfying the user requirements.

• Journal for History of Mathematics
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• v.14 no.1
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• pp.41-46
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• 2001

In the western culture, the definition of infinity and finiteness developed into various features, being combined with classical Hebraism and Hellenism, and after modernism, it has been paralleled with natural sciences within the circle of its tradition, whereas the definition of infinity has been showed in Buddhism, the traditional religion, which has been handed down without scientific consideration, in the eastern culture. This is the most notable characteristics between two hemispheres. In this paper, I will show sameness and differences of these two cultures in terms of defining infinity. Also in terms of examining the definition of infinity and finiteness in the Buddhist principles which has been handed down since 600∼500 B.C. I will show how the definition of Buddhist infinity connect with the mathematical definition of today.

• Journal of the Semiconductor & Display Technology
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• v.13 no.3
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• pp.13-19
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• 2014

Phosphoric acid was used as etching agent instead of conventional peroxide - based chemicals for forming pattern of ultra definition display. Etchant was synthesized by mixing etching agent, oxidation agent, buffer solution, and additive into solvent, deionized water. Thicknesses of copper, main metal of ultra definition display, for etching, were 10,000 and $30,000{{\AA}}$. Etch stop of good low skew for proper pattern formation has been occurred at the content ratio of phosphoric acid 60 - 64%, nitric acid 4 - 5%, additive(potassium acetate) 1 - 3%. Buffer solution(acetic acid) decreased the metal contact angle $63.07^{\circ}$ to $42.49^{\circ}$ for benefiting pattern formation. Content variations on four components (phosphoric acid, nitric acid, acetic acid, potassium acetic acid) of the etchant with storage time were within 3 wt% after 24 hrs of etching work.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.213-214
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• 2014

This paper compares two instantaneous reactive power definitions in DFIG wind turbine with a back-to-back three-level neutral-point clamped voltage source converter under unbalanced grid conditions. In general, conventional definition of instantaneous reactive power is obtained by taking an imaginary component of complex power. The other definition of instantaneous reactive power can be developed based on a set of voltages lagging the grid input voltages by 90 degree. A complex quantity referred as a quadrature complex power is defined. Proposed definition of instantaneous reactive power is derived by taking a real component of quadrature complex power. The characteristics of two instantaneous reactive power definitions are compared using the ripple-free stator active power control algorithm in DFIG. Instantaneous reactive power definition based on quadrature complex power has a simpler current reference calculation control block. Ripple of instantaneous active and reactive power has the same magnitude unlike in conventional definition under grid unbalance. Comparison results of two instantaneous reactive power definitions are verified through simulation.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.5
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• pp.261-266
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• 2019

In order to cope with various issues about access to public health system of Korean medicine and reformation of college curriculum and argument of pseudoscience on Korean medicine etc., a new definition of Korean medicine was devised. Two ways of approach were tried through analysis of precedent cases of definition on traditional medicine firstly and analysis on concept and logic of Korean medicine secondly. As a result, Korean medicine can be defined as a science of theories and application techniques for maintaining health and diagnosing, treating and preventing conditions、causes、prognosis of diseases or damages based on the correlative and complicated understanding about the structure and function of mind and body out of human lives under the environment and society. This definition can be used as a basis to derive legal rights or scope in area of research and education policies and social institutions of the Korean medicine and to confront scientification criticism hereafter.

• Journal of Korean Medical classics
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• v.27 no.2
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• pp.77-95
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• 2014

Objectives : This study was to analyze the definitions of herbs, herbal drugs, crude drugs and natural products in the relevant laws and regulations, understand the related problems, and propose directions for improvement. Methods : I analyzed the legal definitions in respect of herbs, herbal drugs, crude drugs and natural products in relevant laws and regulations since 1945, explained the problems, and suggested the solution-considering the academic stance of Traditional Korean Medicine and the dualistic medical and pharmaceutical system. Results : Herbs are defined as "refined things that are cut and dried in their most original state". The definition of crude drugs includes herbs and the "cell contents, secretion, extracts, minerals and other parts of animals and plants that are used medicinally". The concept of natural products is expanded to adding tissue cultures to the definition of crude drugs. Conclusions : The definition of herbs should at least include all products that are "processed, extracted and prepared" as well as contents that consist of various forms of hospital-prepared herbs. The term "herbal drug" corresponds to a traditional term of "drug", and this should be established as a concept to explain "drugs in raw materials that are used to prepare herbs and/or manufacture herbal medicine". The legal definition of herbs should include the concept of crude drugs. Herbal drug preparations and crude drugs should be included in the definition of herbal drugs.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.38 no.11
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• pp.9-18
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• 2001

Currently most of VPNs within internet has only capability to protect cooperate data. Recently, various types of VPNs are being studied based on the concept of SCG(Secure Communication Group). This paper analyses the problems of path-definition method and area-definition method of VPNs using SCG technology, and discusses the possible models among VPNs using SCG technology. This paper proposes the hierarchal VPN configuration method using SCG number and internet based area definition method, and analyze the characteristics of the proposed VPN model on the point of the authentication frequency and the number of managements keys.