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Upper Mesozoic Stratifraphic synthesis of Korean Peninsula (한반도 후기중생대층 층서종합)

  • Ki-Hong Chang
    • Economic and Environmental Geology
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    • v.32 no.4
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    • pp.353-363
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    • 1999
  • The Cretaceous and the Upper Jurassic strata of the Korean Peninsula, entirely of continental facies, form a sedimentary mega-unit subdivided into three unconformity-bounded units. The lower, Upper Jurassic-early Lower Cretaceous unit (Jasong Synthem) occurs profusely in North Korea and is characterized by volcanic rocks of intermediate to acidic, calc-alkaline to alkaline compositions; but strata of this unit is very rare in South Korea. The middle, Hauterivian-Lower Albian unit occurs commonly in the Korean Peninsula, but some alkalinesubalkaline basalt and andesite occur only in South Korea. A recently obtained U-Pb isochron age about 113.6 Ma (Chang et at, 1998) from the zircon grains of the Kusandong Tuff in the uppermost part of the Haman Formation has thrown much light on the age of this unit. The stratotype of this Hauterivian-L. Albian unit is the Sindong and Hayang Groups of the Kyongsang Basin, where the unit is about twice thick and has more conglomerates than in sedimentary basins in North Korea. The unit shows various sedimentary cycles in different basins showing that the cyclicity is controlled by local crustal motion. The upper, Upper Albian-Upper Cretaceous unit is abundant in South Korea with prolific volcanic rocks which are intermediate to acidic and notably calc-alkaline. In North Korea, however, this unit occurs in only one locality without volcanic rocks and is not voluminous. The distribution of these three unconformity-bounded units shows a stepwise younging toward the Pacific Ocean: the lower unit occurs mainly in N Korea, the middle unit occurs in both N and S Korea, and the upper unit occurs mainly in the southern part of S Korea. The Cretaceous sedimentary basins of S Korea were genetically controlled by paralleling sinistral strike-slip faults parallel to the Pacific margin.

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A Review of the Neurocognitive Mechanisms for Mathematical Thinking Ability (수학적 사고력에 관한 인지신경학적 연구 개관)

  • Kim, Yon Mi
    • Korean Journal of Cognitive Science
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    • v.27 no.2
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    • pp.159-219
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    • 2016
  • Mathematical ability is important for academic achievement and technological renovations in the STEM disciplines. This study concentrated on the relationship between neural basis of mathematical cognition and its mechanisms. These cognitive functions include domain specific abilities such as numerical skills and visuospatial abilities, as well as domain general abilities which include language, long term memory, and working memory capacity. Individuals can perform higher cognitive functions such as abstract thinking and reasoning based on these basic cognitive functions. The next topic covered in this study is about individual differences in mathematical abilities. Neural efficiency theory was incorporated in this study to view mathematical talent. According to the theory, a person with mathematical talent uses his or her brain more efficiently than the effortful endeavour of the average human being. Mathematically gifted students show different brain activities when compared to average students. Interhemispheric and intrahemispheric connectivities are enhanced in those students, particularly in the right brain along fronto-parietal longitudinal fasciculus. The third topic deals with growth and development in mathematical capacity. As individuals mature, practice mathematical skills, and gain knowledge, such changes are reflected in cortical activation, which include changes in the activation level, redistribution, and reorganization in the supporting cortex. Among these, reorganization can be related to neural plasticity. Neural plasticity was observed in professional mathematicians and children with mathematical learning disabilities. Last topic is about mathematical creativity viewed from Neural Darwinism. When the brain is faced with a novel problem, it needs to collect all of the necessary concepts(knowledge) from long term memory, make multitudes of connections, and test which ones have the highest probability in helping solve the unusual problem. Having followed the above brain modifying steps, once the brain finally finds the correct response to the novel problem, the final response comes as a form of inspiration. For a novice, the first step of acquisition of knowledge structure is the most important. However, as expertise increases, the latter two stages of making connections and selection become more important.

An Overview of the Rationale of Monetary and Banking Intervention: The Role of the Central Bank in Money and Banking Revisited (화폐(貨幣)·금융개입(金融介入)의 이론적(理論的) 근거(根據)에 대한 고찰(考察) : 중앙은행(中央銀行)의 존립근거(存立根據)에 대한 개관(槪觀))

  • Jwa, Sung-hee
    • KDI Journal of Economic Policy
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    • v.12 no.3
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    • pp.71-94
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    • 1990
  • This paper reviews the rationale of monetary and banking intervention by an outside authority, either the government or the central bank, and seeks to delineate clearly the optimal limits to the monetary and banking deregulation currently underway in Korea as well as on a global scale. Furthermore, this paper seeks to establish an objective and balanced view on the role of the central bank, especially in light of the current discussion on the restructuring of Korea's central bank, which has been severely contaminated by interest-group politics. The discussion begins with the recognition that the modern free banking school and the new monetary economics are becoming formidable challenges to the traditional role of the government or the central bank in the monetary and banking sector. The paper reviews six arguments that have traditionally been presented to support intervention: (1) the possibility of an over-issue of bank notes under free banking instead of central banking; (2) externalities in and the public good nature of the use of money; (3) economies of scale and natural monopoly in producing money; (4) the need for macro stabilization policy due to the instability of the real sector; (5) the external effects of bank failure due to the inherent instability of the existing banking system; and (6) protection for small banknote users and depositors. Based on an analysis of the above arguments, the paper speculates on the optimal role of the government or central bank in the monetary and banking system and the optimal degree of monetary and banking deregulation. By contrast to the arguments for free banking or laissez-faire monetary systems, which become fashionable in recent years, monopoly and intervention by the government or central bank in the outside money system can be both necessary and optimal. In this case, of course, an over-issue of fiat money may be possible due to political considerations, but this issue is beyond the scope of this paper. On the other hand, the issue of inside monies based on outside money could indeed be provided for optimally under market competition by private institutions. A competitive system in issuing inside monies would help realize, to the maxim urn extent possible, external economies generated by using a single outside money. According to this reasoning, free banking activities will prevail in the inside money system, while a government monopoly will prevail in the outside money system. This speculation, then, also implies that the monetary and banking deregulation currently underway should and most likely will be limited to the inside money system, which could be liberalized to the fullest degree. It is also implied that it will be impractical to deregulate the outside money system and to allow market competition to provide outside money, in accordance with the arguments of the free banking school and the new monetary economics. Furthermore, the role of the government or central bank in this new environment will not be significantly different from their current roles. As far as the supply of fiat money continues to be monopolized by the government, the control of the supply of base money and such related responsibilities as monetary policy (argument(4)) and the lender of the last resort (argument (5)) will naturally be assigned to the outside money supplier. However, a mechanism for controlling an over-issue of fiat money by a monopolistic supplier will definitely be called for (argument(1)). A monetary policy based on a certain policy rule could be one possibility. More importantly, the deregulation of the inside money system would further increase the systemic risk inherent in the current fractional banking system, while enhancing the efficiency of the system (argument (5)). In this context, the role of the lender of the last resort would again become an instrument of paramount importance in alleviating liquidity crises in the early stages, thereby disallowing the possibility of a widespread bank run. Similarly, prudential banking supervision would also help maintain the safety and soundness of the fully deregulated banking system. These functions would also help protect depositors from losses due to bank failures (argument (6)). Finally, these speculations suggest that government or central bank authorities have probably been too conservative on the issue of the deregulation of the financial system, beyond the caution necessary to preserve system safety. Rather, only the fullest deregulation of the inside money system seems to guarantee the maximum enjoyment of external economies in the single outside money system.

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An Analysis of Linkage of Scientific and Technological Knowledge to Industry (과학기술 지식흐름의 산업연계 파급경로 분석)

  • Park, Hyun-Woo;Lee, Chang-Hoan;Yeo, Woon-Dong
    • Journal of Korea Technology Innovation Society
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    • v.11 no.1
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    • pp.91-117
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    • 2008
  • The relationships between science, technology, and industry are very complicated and vary according to time. Thus, it would be almost impossible to combine the three categories in a single model. However, the linking of science, technology, and industry, which are divided according to their respective classification standards, is a starting point from which to understand how science and technology, technology and industry, and further science, technology, and industry are related to each other. Studies have been carried out to analyze the relationship between science and technology and between technology and industry, whereas no study has been undertaken to get an overall view of science, technology, and industry. Since an appropriate methodology or an analytical model has not been suggested, this paper proposes a model for generally analyzing science, technology, and industry. More specifically, this paper examines the methodology for linking science, technology, and industry. This paper uses citation analysis to analyze knowledge flow such as absorption and utilization of given knowledge, looks at the provision of knowledge to create new knowledge, and examines the use of network analysis to analyze the complicated phenomenon of knowledge flow. This paper proposes an empirical study of trend analysis of technological innovation by looking into a linkage structure of knowledge flow among science, technology, and industry based on the classification linkage and analysis methodology using scientific paper and patents.

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Rawls' Liberal Theory of Justice and Ecological Justice (롤즈의 자유주의적 정의론과 생태적 정의)

  • Choi, Byung-Doo
    • Journal of the Korean association of regional geographers
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    • v.11 no.4
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    • pp.476-496
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    • 2005
  • This paper considers some significances and limitations in application of Rawls' liberal theory of justice to conceptualization of environmental and ecological justice. It first reviews Rawls' liberal theory of justice, then examines how his theory of justice considers natural resources and can be applied to develop distributive theory of environmental justice, and finally explores what kinds of problems would be generated when Rawls' theory of justice is to be extended to animals and other natural components. In Rawls' theory of justice the status of natural resources is described as a objective condition for justice, but it is argued that natural resources should be seen as a substantial component of just production and distribution. It also can be stressed that his theory of justice does not secure a just result of resource distribution, even though it has a great significance for just procedure of distribution. Finally, it seems hardly possible to extend Rawls' theory of justice to animals and other natural components to develop a Rawlsian theory of ecological justice, because liberalism and Western tradition of science on the basis of which Rawls' theory of justice has developed presuppose an ontological dualism of human beings and other natural components, and hence cannot recognize the inherent value of nature.

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Geospatial Analysis and Modeling in Korea: A Literature Review (한국의 지리공간분석 및 모델링 연구)

  • Lee, Sang-Il;Kim, Kam-Young
    • Journal of the Korean Geographical Society
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    • v.47 no.4
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    • pp.606-624
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    • 2012
  • The main objective of this paper is to provide an adequate and comprehensive review of what has been done in South Korea in the field of geospatial analysis and modeling. This review focuses on spatial data analysis and spatial statistics, spatial optimization, and geosimulation among various aspects of the field. It is recognized that geospatial analysis and modeling in South Korea got through the initial stage during the 1990s when computer and analytical cartography and GIS were introduced, moved to the growth stage during the first decade of the $21^{st}$ century when there was a surge of relevant researches, and now is heading for its maturity stage. In spatial data analysis and spatial statistics, various topics have been addressed for spatial point pattern data, areal data, geostatistical data, and spatial interaction data. In spatial optimization, modeling and applications related to facility location problems, districting problems, and routing problems have been mostly researched. Finally, in geosimulation, while most of research has focused on cellular automata, studies on agent-based model and simulation are in beginning stage. Among all these works, some have fostered methodological advances beyond simple applications of the standard techniques.

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A meta analysis of maxillary expansion : comparisons of intercanine/intermolar expansion and rapid/slow expansion (상악확장술 치료효과의 메타분석 : 견치간 폭경과 대구치간 폭경 확장의 비교 및 급속과 완속 확장의 비교)

  • Ko, Chang-Hee;Lim, Sung-Hoon;Yoon, Young-Jooh;Kim, Kwang-Won
    • The korean journal of orthodontics
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    • v.34 no.1 s.102
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    • pp.23-31
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    • 2004
  • As a research method that weighs and combines evidence, meta analysis produces evidence that is more powerful than the original studies. The purpose of this study was to compare the jntercanine/intermolar expansion and rapid/slow expansion in the maxillary expansion treatment using meta analysis. Medline was searched from 1979 to 2000 for all studies examining the stability of transverse expansion of the human maxilla, and 388 articles were found. Then these articles were reduced to 7 based on the defined inclusion and exclusion criteria, and a cumulative Meta evaluation score was computed for each study. The results were as follows; 1. The mean expansion in intermolar width was 6.0mm. of the 6.0mm, 4.8mm was retained and $20.0\%(1.2mm)$ was relapsed while wearing retainers. 2. In intercanines width, the mean expansion was 3.7mm. of the 3.7mm, 2.6mm was retained and $29.7\%(1.1mm)$ was relapsed while wearing retainers. 3. The differences In the amount of expansion and relapse between rapid expansion group and slow expansion group were less than $6\%(0.1-0.3mm)$. But, there might be differences in the skeletal/dental exapnsion ratios according to the expansion method.

CHILDHOOD TRAUMA:PSYCHIATRIC OVERVIEW (아동기 외상의 정신과적 개관)

  • Han, Sung-Hee
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.13 no.1
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    • pp.3-14
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    • 2002
  • Childhood psychic trauma appears to be a crucial factor in the development of serious disorders both in childhood and in adulthood. Traumatized children show strong tendency to revisualize or re-feel a traumatic events. Play and behavioral reenactments are frequent manifestations of both the single blow and the long-standing traumas in childhood. Those children who suffer the results of single, intense terror appear to exhibit detailed memory, retrospective reworkings and misperceptions. In long-standing or repetitive trauma, children would show psychic numbing, self-hypnosis, dissociation and rage. Child's brain is undergoing critical and sensitive periods of differentiation. During this time, developing central nervous system is exquisitely sensitive to stress. Stressor-activated neurotransmitters and hormones can play major roles in neurogenesis, migration, synaptogenesis, and neurochemical differentiation. Internal opiate system operates in some trauma and causes the victim to fail to respond, to avoid, to shut off feelings. Evidence is also accumulating in traumatology that dysfuntion of locus coeruleus and ventral tegmental neucleus system leads to catecholamine receptors hypersensitivity. This change result in hypervigilance, increased startle, affective lability, and increased autonomic nervous system hyperreactivity. Another site of action of trauma on the brain is hypothalamic-pituitary-adrenal axis. Individuals with PTSD do not have enough cortisol to halt the alarm reaction. When children are exposed to long-standing extreme events, massive attempts to protect the psyche and to preserve the self are put into gear. These developmental traumas mobilize various kinds of defense mechanisms. Massive denial, dissociation, self anesthesia, identification with aggressor and aggression turned against the self often lead to profound character changes in the youngsters.

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The Welfare Effects of Advertising: The Economic Rationale for Regulation of Advertising (광고(廣告)의 후생효과(厚生效果) : 광고규제(廣告規制)의 경제적(經濟的) 논거(論據))

  • Lee, Kyu-uck
    • KDI Journal of Economic Policy
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    • v.12 no.3
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    • pp.95-123
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    • 1990
  • Advertising, while providing a linkage between sales and consumption, helps promote rational consumption patterns by expanding the scope of information for consumers facing an ever-increasing array of consumption decisions. In so doing, advertising promotes competition among suppliers and sellers, thereby improving market transparency. Intrinsically, advertising can influence the instantaneous decisions made by consumers, and because of this peculiar feature of advertising, ensuring fair advertising practices is a policy issue of great importance. Concurrently, discerning whether the amount of advertising, which is determined by the profit motive of advertisers, is socially appropriate or whether this amount constitutes a waste of scarce resources is a necessary and indispensable consideration in establishing a public policy to respond to the mounting deluge of advertising. Although the Fair Trade Act and numerous other related laws are being enforced with regard to advertising, it may be difficult to say that a unified, practicable and logical basis for regulating the variegated and complex forms of advertising has been established. This paper examines the various theoretical arguments on the welfare effects of advertising as a rationale to justify regulation from the viewpoint of economics. In this manner, this paper helps define the essential nature of advertising and seeks to present a rational approach toward the regulation of advertising.

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Effects of Ipriflavone on bone remodeling in the rat calvarial cell (백서 두개관세포에서 Ipriflavone이 골조직 개조에 미치는 영향)

  • Lee, Yong-Seung;Kim, Young-Jun;Lee, Ki-Heon;Hwang, Hyeon-Shik
    • The korean journal of orthodontics
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    • v.35 no.4 s.111
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    • pp.275-285
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    • 2005
  • Ipriflavone (isoprofoxyisoflavone), a synthetic derivative from soy isoflavone diazein, has been shown to inhibit bone resorption and perhaps stimulate bone formation This study was performed to examine the effects of ipriflavone on the proliferation and bone remodeling in rat calvarial cells in vitro The rat calvarial cells were isolated from fetus aged 20 to 21 days and cultured In BGJb media The graded concentration of ipriflavone $(10^{-9}\;10^{-5}M)$ was administered into cultured cells. When the cell proliferation was estimated through the measurement of MTT assay, there was no increase in cellular proliferation of the rat calvarial cell at any ipriflavone concentration. The cellular activity was evaluated through the formation of mineralized nodules stained by alizarin red. The formation of mineralized nodules significantly increased at concentrations of $10^{-8}M,\;10^{-7}M\;and\;10^{-6}M$ ipriflavone. Reverse transcription-polymerase chain reaction analyses (RT-PCR) were done at 7 and 14 days after culture to detect the expression of Bone Sialoprotein (BSP), Type I Collagen (COL I) and Osteocalcin(OCN) As a result, the expressions of BSP and COL I increased on the 7th day of culture and the expression of OCN increased on the 14th day of culture. These results indicate that ipriflavone facilitates the bone remodeling process bvy promoting rat calvarial cell differentiation aid stimulating mineralization through increased expression of extracellular matrix genes. such as BSP. COL I and OCN.