• Title/Summary/Keyword: 우주

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Analysis of the Conceptual Understanding of In-service and Pre-service Earth Science Teachers about 'Stellar Evolution' (현직 및 예비 지구과학교사의 '별의 진화'에 대한 개념 이해 분석)

  • Ha, Min-Kyoung;Sohn, Jungjoo
    • Journal of the Korean earth science society
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    • v.40 no.5
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    • pp.538-547
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    • 2019
  • This study analyzes the conceptual understanding of in-service and pre-service earth science teachers about the H-R diagrams and evolution of stars using conceptual status analysis categories. The results show that (a) many teachers use unscientific language in the Intelligibility range, (b) teachers are categorized in Low scientific inquiry ability related to graph creation and unscientific analogy for scientific concept which is hightly corelated to the possibility of misunderstanding in the teaching process, and (c) pre-service teachers lack the understanding of the secondary science curriculum. It is necessary to develop pre-service curriculum that can be applied to the school site. In the category of Plausibility range, (d) both groups understood the cosmological meaning of stellar evolution. However, pre-service teachers do not specifically explain the mechanism of a star. In the category of Fruitfulness range, in-service teachers come up with educational problems reflecting the academic characteristics of earth science and apply their knowledge to actual problem solving. On the other hand, pre-service teachers show high nonresponse ratio, they do not see the H-R diagram and the evolution of stars as a practical concept. In the analysis process, both groups are found to have many unscientific conceptions about the H-R diagram and evolution of stars. Therefore, it is suggested that caution be used in developing a professional development program of earth science teachers.

Spectral Characteristics associated with Heavy Metal Concentration and Mineral Composition in Cropland and Rice Field Soils from Downstream of an Abandoned Coal Mine (폐석탄광 하류 밭토양 및 논토양의 중금속 함량과 광물조성에 따른 분광학적 특성)

  • Seo, Jihee;Yu, Jaehyung;Koh, Sang-Mo;Lee, Bum Han
    • Economic and Environmental Geology
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    • v.53 no.6
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    • pp.743-753
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    • 2020
  • This study analyzed heavy metal concentration, mineral composition, and spectral characteristics of heavy metal contaminated soil samples of cropland and rice field located in downstream of abandoned Okdong coal mine. X-ray fluorescence analysis detected heavy metal elements including cadmium, copper, arsenic, lead, zinc and nickel in the soils. Both cropland and rice field samples were severely contaminated with arsenic showing higher concentration over the concerned standard. The pollution index of cropland samples was higher than that of rice field samples. X-ray powder diffraction analysis identified that the mineral composition of cropland and rice field samples is similar with quartz, calcite, kaolinite, illite, smectite, magnetite and hematite. The range of organic matter content were more widely distributed in cropland samples. The spectral analysis showed that the reflectance spectra and the absorption features of cropland and rice field samples were alike. The absorption features that appeared near 490nm and 900nm were attributed to the ferric iron, and clay minerals such as kaolinite and smectite caused the absorption features at 1410nm, 1910nm and 2200nm. The reflectance of the soil spectral decreased with an increase in organic content. The absorption depths of both types of soil samples decreased with higher organic matter content at 490nm and 1916nm as well as higher heavy metal concentration.

Development and Validation of the GPU-based 3D Dynamic Analysis Code for Simulating Rock Fracturing Subjected to Impact Loading (충격 하중 시 암석의 파괴거동해석을 위한 GPGPU 기반 3차원 동적해석기법의 개발과 검증 연구)

  • Min, Gyeong-Jo;Fukuda, Daisuke;Oh, Se-Wook;Cho, Sang-Ho
    • Explosives and Blasting
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    • v.39 no.2
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    • pp.1-14
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    • 2021
  • Recently, with the development of high-performance processing devices such as GPGPU, a three-dimensional dynamic analysis technique that can replace expensive rock material impact tests has been actively developed in the defense and aerospace fields. Experimentally observing or measuring fracture processes occurring in rocks subjected to high impact loads, such as blasting and earth penetration of small-diameter missiles, are difficult due to the inhomogeneity and opacity of rock materials. In this study, a three-dimensional dynamic fracture process analysis technique (3D-DFPA) was developed to simulate the fracture behavior of rocks due to impact. In order to improve the operation speed, an algorithm capable of GPGPU operation was developed for explicit analysis and contact element search. To verify the proposed dynamic fracture process analysis technique, the dynamic fracture toughness tests of the Straight Notched Disk Bending (SNDB) limestone samples were simulated and the propagation of the reflection and transmission of the stress waves at the rock-impact bar interfaces and the fracture process of the rock samples were compared. The dynamic load tests for the SNDB sample applied a Pulse Shape controlled Split Hopkinson presure bar (PS-SHPB) that can control the waveform of the incident stress wave, the stress state, and the fracture process of the rock models were analyzed with experimental results.

A study on the effect of perceived amount of information in a fashion crowdfunding project on perceived risk and intention to participate (패션 크라우드펀딩 프로젝트에서 지각된 정보의 양이 소비자 위험지각 및 참여의도에 미치는 영향 연구)

  • Lee, Eun-Jung;Shim, Woo Joo
    • The Journal of the Convergence on Culture Technology
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    • v.7 no.3
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    • pp.365-374
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    • 2021
  • Recently, the high growth rate and advantages of the crowdfunding market have also led to increased participation of brands and companies, and this also applies to fashion business. Risk has been noted to be a key factor in consumer behavior in crowdfunding. With the high-risk context of crowdfunding where supporters inevitably bear to pay full amount of price before receiving the actual products. Factors enhancing or inhibiting perceived risk of crowdfunding need to be explored. The past literature on perceived risk and consumer attitudes in crowdfunding has expanded, but it has rarely covered the context of experience goods such as fashion products. In addition, the platform characteristics in relation to perceived risk should be addressed. The current study attempts to address the effect of the perceived amount of information offered in a fashion crowdfunding project on perceived risk and the intention to participate in the project. For the experiment of this study, a fictitious crowdfunding page for fashion products was set as the stimuli. A total of 240 Korean participants were recruited and their responses were statistically analyzed using SPSS 24.0 software. In the results, the greater the amount of detailed information about the fashion crowdfunding project, the higher the intention to participate the project. The greater the amount of information provided, the lower the perceived risk of consumers. Moreover, the lowered perceived risk affected the intention of participate. Perceived risk has a partial mediation in the relationship between the amount of information and intention to participate. Theoretical and managerial implications are discussed.

An analysis of the human difficulties and the relationship of things in Zhuangzi thought (시석장자사상중인지고경여물지관계(試析莊子思想中人之苦境與物之關係))

  • Han, Kyung-Duk
    • The Journal of Korean Philosophical History
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    • no.25
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    • pp.333-354
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    • 2009
  • Zhuangzi contends that one of the reasons to cause life difficulties is mistaking the truth of cosmos and the existence meaning of human. There is no difference of value between the existence of human and universal creatures. However, "human mind" can not being peaceful because of " ChengXin(成心)" causes the difference of right and wrong. Zhuangzi contends the ideal world is "ZhiDe zhi World(至德之世)" of unmoved mind. Because of the value of "RenYiDaoDe(仁義道德)" in politics, the status of ideal existence of human and creatures is destroyed, i.e., disturbing the status of peaceful mind. This is also a reason of life difficulties. Zhuangzi contends the reasonable relationship of human and creatures is to recognize creatures as creatures, and therefore, there is no difference of value between creatures. Additionally, one shall understand the concept of "universal creatures are the same(萬物?一)" is based on the fact of continuous change of universal creatures. The socalled concept of "universal creatures are the same(萬物?一)" in Zhuangzi's thought is based on three dimensions: one is the materials of forming universal creatures; one is the same meaning of "Hisn" between human and creatures, and universal creatures are continuously changing. Therefore, one shall get a clear understanding of the nature of things, and one may treat the universal creatures in the concept of "universal creatures are the same(萬物?一)".

A Study on the Changes of Literary Thought in the Middle of the Yi Dynasty through Seo Kyung Duk (서경덕(徐敬德)을 통해 본 조선 중기 근기(近畿) 문학 사상의 변화)

  • Kim, Seong-ryong
    • Journal of Korean Classical Literature and Education
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    • no.39
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    • pp.181-220
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    • 2018
  • I analyze Seo Kyung Duk's (徐敬德, 1489-1546) phonetic essay and deduce whether it is related to the Tang poetry style [唐詩風], which was popular in the 16th century. Seo Kyung Duk was known as a Ki[氣]-oriented scholar and a kind of numerologist. He taught people regardless of their status differences, which gave them an open-minded attitude. Most of them were active in the areas near Seoul. Around this time, the Tang poetry style began to be popular in the Yi dynasty. Most of the leading writers of this literary trend were his students. He thought that the universe was made up of the movement of Ki[氣] and that the movement followed the correct order of numbers. Ki[氣] is active, automatic, and inevitably creates the universe in the order of numbers. The reasons for their existence are clear. All present existences, including human beings, fit together and collectively harmonize by themselves. Beyond the present discrimination, the Great Body [本體] returns to a clean and transparent unity. As such, the school presented the political stance of taking the differences of the present world into harmony and the literary position of trying to experience the clean and transparent unity of the Great Body through an aesthetic experience.

Analysis of Paleo Sedimentary Environment of Gochang Coast Using Grain Size Distribution Characteristics (입도분포 특성을 기반으로 한 고창 연안의 과거 퇴적환경 분석)

  • Han, Min;Yang, Dong-Yoon;Park, Chanhyeok
    • Journal of The Geomorphological Association of Korea
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    • v.25 no.3
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    • pp.43-55
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    • 2018
  • This study aimed to identify different sedimentary environments of Gochang coast according to geomorphic conditions of each bore hole. To achieve the aim, this study utilized the classification of sedimentary environmental conditions of surface sediment, which was based on grain size distribution characteristics.In other words, three sedimentary environmental conditions ofsandy flat + sand beach, coastal sand dune and weathered bedrock soil, which were distinguished based on grain size distribution characteristics of mean-sorting for surface sediments, were applied to the sediments of bore holes. Four sedimentary environments could be identified in Gochang coast. First, the lake sedimentary environment originated from terrestrial sediments seems to have been dominated by weathered bedrock soil that the surface flow has deposited in a coastal wetland or a boundary, which is affected by the sea. Second, the lake sedimentary environment that is little affected by coastal sand dunes is located at the center of a valley, which is connected to the land, and the dune slack of Saban-ri. The surface flow of weather bedrock soil is the main source of deposits. However, there seems to have been a temporary influence of the sea. Third, the lake sedimentary environment that is strongly affected by coastal sand dunes is located at the dune slack of Yeongjeong-ri. This environment shows traces of a change from a coastal sand dune into the dune slack. Finally, the coastalsand dune sedimentary environment, which wasinvestigated by boring the current coastal sand dune, shows a temporary influence of the land but seems to have maintained the overall stability. Consequently, this study demonstrated that the grain size distribution characteristics of the present surface sediments could be effectively applied to identify the sedimentary environments of the paleo bore hole sediments. In addition, the paleo change of sedimentary environment could also be identified in many places of Gochang coast. If the results of this study are combined with the age dating and geochemical analysis in future works, the paleo environmental change in Gochang coast will be restored more precisely.

A Moral Approach of Yulgok Philosophy on Environmental Issue (환경문제에 대한 율곡철학의 도덕론적 접근)

  • Jeong, Won-Gyo
    • The Journal of Korean Philosophical History
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    • no.43
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    • pp.33-53
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    • 2014
  • It's the situation that modern technological civilization shakes the life environment fundamentally without a serious reflection on the dangers. The sense of crisis' brought the rise of modern Ecology in awareness of survivability of the humanity. Because the serious reflection is not just a campaign for environmental protection, but is to establish the values which is possible to coexist and to make harmony between the nature and man, man and man, and to form a healthy relationship through philosophical thought and practice has intrinsic value for human and nature. Under these circumstances, if Yulgok lives now and he is questioned by the ecological theorists of the 21st century that "What do you think about the serious environmental problem of present times?", what really would be his explanation? In the presentation methods of the explanation, will question first what contents western ecologists who study Theory of the environment in technology, Deep Ecology, and Social Ecology propose, then will compare and introduce what similarities and differences from theirs. As a result, we'll be found that Yulgok's thought, moral consciousness, about the nature and humanity as a confucian scholar.

Ch'oe Han-gi's Reflection on Relationalities in Existence (최한기의 존재론적 관계성 성찰)

  • Rhee, Myung-Su
    • The Journal of Korean Philosophical History
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    • no.59
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    • pp.395-423
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    • 2018
  • Since the middle of the 19th century, East Asia, especially Korea, was oppressed externally by the imperialism of Japan and others while internally long-lasting political convention like in-law government was driving the country into troubles at home and abroad. Witnessing such a situation and building up scholarly capability through reading over nearly all spheres, a Confucian philosopher, Ch'oe Han-gi (崔漢綺, 1803-1877), philosophized about the clue to the solution of such a choking phenomenon. Ch'oe believed that there was movement, ki (matter, material force, energy) of revolving transformation inherent in all things, people, or objects. Grasping even the principle and order of existence inherent in things from the viewpoint of ki, he tried to change the traditional theory on the law of existence of things that there existed an ontological reason lacking in motility, which was more dominant than anything existing in the universe and which ruled over the world. From this, he elucidated that the Way, an identity that rules over all affairs and things, was not simply one but diverse. This means, on one hand, that he tentatively accepted the relativity of things. On the other hand, he also taught us "oneness in all things" in which all including human beings exist in close connection to each other transcending the relativity or "agreement" in which they exist in harmony as one and "unity" in which they are united into one.

A study on the value of Korean during the Joseon Dynasty (조선시대(朝鮮時代)의 한국적 가치 연구)

  • Han, Sung Gu
    • The Journal of Korean Philosophical History
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    • no.39
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    • pp.85-114
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    • 2013
  • Traditional values refer to one's attitudes or perspectives developed by negotiating with oneself, others, society, world, nature and universe, which include thoughts on what is right, desirable, and what is dos and don'ts. The purpose of this study was to investigate values which Korean people traditionally emphasized, and their changes by epochal situation focused on the Choson Era. Also, this study intended to assist in finding values and meaning which should be passed down and manifested in contemporary society based on the study results. In this context, I select some positive values in the background of the Joseon dynasty. As traditional values or ethics in Korea destroyed and distorted going through the period of Japanese colonialism, all the existing social culture and traditional culture were denied, which resulted in vanishing common value which led community for several hundred years. The loss of common value caused community destruction and collapse, and made Korean people seek to survival, success and advancement in life as suffering from severe conflict of values. Experience of hollow state of mind caused by historical and cultural severance left distorted and degenerated values to Korea people, which made them pursue false values without realizing true meaning of traditional values. The true meaning of traditional values should be universal no matter how society changes, and could be milestone to contemporary people wandering aimlessly. Realizing and reconsidering the meaning of traditional values to found comtemporary values of Korean people by reflecting on history can produce significant results beyond age-old debate about East or West, and tradition or modernity.