• 한국환경과학회지
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• 제31권1호
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• pp.9-21
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• 2022

Today's cities require deeper understanding of the thermal environment and PM₁₀ as their management becomes more critical. Based on these circumstances, this study investigated the Granger causality between the thermal environment and PM₁₀ of the 25 districts of Seoul, the most populous and urbanized city in Korea. The results of the Granger causality test on the thermal environment and PM₁₀ were classified into 12 types. Except for type 12, the temperature and urban island heat intensity of the other 11 types operated as a Granger-cause to each other in both directions. Temperature operates as a Granger-cause of urban island heat intensity in type 12. The PM₁₀ level and urban pollution island intensity operated as a Granger-cause to each other in all districts. For types 1 and 2, thermal environment operated as a Granger-cause to PM₁₀ in one direction, and type 3-type 12 confirmed that thermal environment and PM₁₀ operated as a Granger-cause in both directions. Findings reveal the intricate causalities between thermal environment and PM₁₀ at the district level and suggest mitigation strategies that are more location based.

• 대한지구과학교육학회지
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• 제6권1호
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• pp.28-39
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• 2013

The purpose of this study is to investigate the conceptions about altitude of the Sun of elementary students according to differences by the spatial ability. In this study through the qualitative analysis, 4 students who were similar understanding levels of concepts to altitude of the Sun and differences by the spatial ability were selected out of 75 in 6th grade elementary located in Sunchang, Jellabuk-do Province. 4 students for the qualitative analysis were selected by the test instrument of spatial ability and altitude of the Sun. The results of study was students with higher spatial ability were higher understanding levels of concepts to altitude of the Sun. However, both of student with higher and lower spatial ability showed a false concept to the expanded concepts into outer space like a cause of seasonal change, change of altitude of the Sun by latitude unlike the intution. Students with lower spatial ability didn't form the scientific concepts, not only a cause of seasonal change and change of altitude of the Sun but also difference of energy density by altitude of the Sun. A student of two with lower spatial ability has been impediment strongly to form the scientific concept by the false concepts to the distance. The findings were as follows; Learning to altitude of the Sun regardless of the difference of spatial ability should be learned to interact to the intution, celestial movement and model experiment. To students with lower spatial ability should be developed teaching methods to understand the relation between the Sun and celestial movement.

• 한국도서관정보학회지
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• 제16권
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• pp.221-249
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• 1989

The purpose of this study is to analyze the factors influencing on the organizational changes of the university libraries. Results of the analysis, that is, factors that cause the library organization to change, are as follows 1. Changes in library size physical facilities, growth and diversity of library collections, change in personnel organization, role enrichment and faculty status for librarians, management pattern of library director, change in financial su n.0, pport. 2. Change in program : change in goals and objectives, expansion of service programs, enhancement of library functions. 3. Library automation : introduction and development of many library automation projects. 4. Introduction of information technology : development and distribution of computer and related software, telecommunication, and new media. 5. Changes in user needs : many-sided demands for collections, spaces, and services. 6. Many other environmental factors related to library organization.

• 한국미생물·생명공학회지
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• 제25권3호
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• pp.240-247
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• 1997

Bacillary is the most common form of H. pylori observed during human infection. However, it is known that the morphology change of H. pylori from bacillary to coccoid can be occurred with a response to the environmental stresses such as the nutrient depletion, accumulation of toxic metabolites, pH alteration, and exposure to antimicrobial agents. The coccoid form of H. pylori, which is viable but non-culturable in vitro, seems to be the major cause of antibiotic resistancy and high reinfectability of H. pylori. In this regard, we studied the environmental factors that can induce the morphological change in vitro of H. pylori, and the change of fatty acid composition of plasma membrane. The morphological change from bacillary to coccoid could be observed with the depletion of nutrients, pH variation and reactive oxygen species added in the culture media. This morphologic conversion was paralleled by a dramatic decrease in unsaturated fatty acids and an increase in saturated fattv acids of plasma membrane. The change in composition of membrane fatty acid seems to be a kind of protection mechanism of H. pylori against these environmental stresses.

• 철학연구
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• 제129권
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• pp.291-313
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• 2014

본 논문의 목적은 "자연학"을 중심으로 아리스토텔레스의 변화(kinesis) 개념을 해명하는 것이다. 아리스토텔레스에 의하면, 변화란 가능태로 존재하고 있던 형상과 질료가 현실태로서의 형상과 질료로 존재하게 되는 과정이다. 변화에 대한 아리스토텔레스의 정의로부터 우리는 중요한 몇 개의 결론을 이끌어 낼 수 있다. 첫째, 모든 변화는 무엇인가를 지향하고 있다. 둘째, 만약 변화가 왜 일어나는지를 모른다면 우리는 변화가 무엇인지를 이해할 수 없다. 셋째, 변화가 일어나기 위해서는 변화를 일으키는 자(者)가 반드시 있어야 한다. 넷째, 변화의 주체와 변화의 원인은 단 한 번만 현실화된다. 아리스토텔레스에 의하면, 모든 변화는 지속적으로 존재하는 기체(基體)의 변화이다. 기체는 공간, 시간, 물리적 크기 등과 같은 '무한자'(to apeiron)를 매개로 해서 변화한다. 아리스토텔레스에 의하면, 완전한 것과 무한자를 동등한 것이라고 생각하는 것은 불합리하다. 왜냐하면 그렇게 생각할 때 한계를 결여하고 있는 것이 한계를 가지는 것으로 되기 때문이다. 한계를 결여하고 있는 것으로서의 무한자는 세계를 포섭하는 것이 아니라 세계에 포섭되어 있다. 그리고 한계를 결여하고 있는 것으로서의 무한자는 인식될 수 없다. 왜냐하면 무한자는 형상이 없는 질료, 즉 질료 그 자체이기 때문이다. 아리스토텔레스에 이르기까지 전통적으로 무한자의 지위는 존엄한 것이었다. 왜냐하면 무한자는 모든 것을 포섭하고 있는 전체였기 때문이다. 그러나 아리스토텔레스는 무한자의 존엄한 지위를 끌어내리고 있다. 아리스토텔레스에게 무한자는 자연에 내재하는 것이지 초월적인 원리가 아니다. 아리스토텔레스의 이와 같은 발상은 철학적 관점에 있어서의 혁명이었다.

• 대기
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• 제15권1호
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• pp.69-74
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• 2005

In this short article, oceanic processes that could have strong effect on the climate have been explained while focusing on the oceanic thermohaline circulation (THC). First, the structure of THC is explained using a simple scaling law. Then, the thermohaline catastrophe, which is believed to be a cause of a rapid climate changes observed in paleoclimate records, and interdecadal variations in THC are explained. The interactions between the oceans and $CO_2$ are also mentioned briefly.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1989년도 춘계학술대회 논문집
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• pp.107-109
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• 1989

Based on the ferroelectric microstructural residual stress model, the relation between grain size and residual elastic energy was proposed. It was found that the residual elastic energy increased with decreasing grain size by modeling and DSC results. This residual elastic energy change with grain size which induce the phase transituion mode change was the cause of a diffuse phase transition in small grain size.

• Journal of Forest and Environmental Science
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• 제28권2호
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• pp.97-105
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• 2012

A Gangwon region consisting of over 80% of forest area has industries that have been developed by utilizing its clean region image. However, the recent climate change has increased the forest disease & insect pest as well as the forest fire and the major cause is known to be the increase in the frequency of a drought occurrence. From the aspect of climate change, it can be said that drought and forest are important in every aspect of the adaptation and mitigation of climate change measure as they increase forest disease & insect pest that leads to desolation of usable forest resource. In addition, the increase of forest fire reduces resources that can absorb greenhouse gas, which leads to increase in green house emission. The purpose of this study is to provide a motive for concentrating administrative power for protecting forest in a Gangwon region by selecting a drought management needed local government through a drought forecast according to the climate change scenario of a Gangwon region.

• The Korean Journal of Ecology
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• 제16권1호
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• pp.17-26
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• 1993

We investigated the ph change of water caused by several fuel gases regarded as the main cause of the air pollution, To find out the main cause of increase of the acidity of the rain. We measured it while injrcting each fuel gas directiy to the distilled water. It was observed that bunker-c oil gas and anthracite coal gas were the main cause to make the ph of the solution lowest. We examined the effects of simulated acidic water solutions on several plant species. Simulated acidic rain made by bunker-c oil gas has significant symptom on the saxifraga stolonifera and commelina communis, while no injury was observed on plants exposed to simulated rainfall made by anthracite coal gas.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2003년도 춘계학술발표대회 개요집
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• pp.87-89
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• 2003

The yield strengths of austenitic stainless steel have been approximately doubled by increasing the nitrogen content. But, the increasing the nitrogen cause of increase the pressure of metal vapor inside the keyhole in electron beam welding. During welding, eruptions of keyhole often occur that cause excessive spatter, concavity, and porocity in the weld zone. Additionally the fast evaporation of nitrogen content cause of decrease the strength of weld zone. Therefore in this paper, we investigated of the weldability of electron beam welding and the change of chemical content after welding for strengthened austenitic stainless steel, measured the deformation scale of both of electron beam and narrow gap TIG and the spike fluctuation in the root.