• Title/Summary/Keyword: Change history

Search Result 1,687, Processing Time 0.026 seconds

The Educational Effect of History Lessons on the Subject of Climate Change Regarding Environmental Awareness (기후 변화 주제를 다룬 역사 수업의 환경교육 효과)

  • Kim, Eun-Jeong;Yun, Sun-Jin
    • Hwankyungkyoyuk
    • /
    • v.22 no.2
    • /
    • pp.56-78
    • /
    • 2009
  • Currently, climate change is regarded as one of the most important environmental issues in the 21st century. However, climate change education is not seriously carried out in schools. This study is concerned about enhancing students' recognition about climate change and actions responding to climate change through an history discipline. More specifically, this study tried to identify the effect of history lessons on environmental education, especially focused on climate change, by performing an experiment. The experiment was designed based on Solomon four-group design and carried out in one high school in Gwangmyeong city. Findings of the experiment are as follows. First, students who had taken the reorganized history lesson based on climate change - that is, students with experimental treatments - gained higher understanding of climate change than before and students of control groups. Second, students with experimental treatments gained higher understanding about relationship between history and climate change. Third, students with experimental treatments showed higher possibility of taking responding actions to climate change. In conclusion, history lessons reorganized with environmental issues, for instance climate change, have big potential for environmental education since they contribute to enhancing environmental recognition and prompting responding actions through exploration the effects of existing historical facts. Interdisciplinary approach like that taken in this study will provide students with more comprehensive and extended prism for the environment.

  • PDF

Climate Change and Individual Life History (기후변화와 개체의 생활사)

  • Lee, Who-Seung
    • Ocean and Polar Research
    • /
    • v.34 no.3
    • /
    • pp.275-286
    • /
    • 2012
  • Over the last 20 years there have been more than 3000 peer-reviewed papers relating to climate change and biodiversity published, and still the numbers are increasing. However, most studies focused on the impacts of climate change at population or community levels, and the results invariably reveal that there has been, or will be, a negative effect on the structure and pattern of biodiversity. Moreover, the climate change models and statistical analyses used to test the impacts are only newly developed, and the analyses or predictions can often be misled. In this review, I ask why an individual's life history is considered in the study how climate change affects biodiversity, and what ecological factors are impacted by climate change. Using evidence from a range of species, I demonstrate that diverse life history traits, such as early growth rate, migration/foraging behaviour and lifespan, can be shifted by climate change at individual level. Particularly I discuss that the optimal decision under unknown circumstance (climate change) would be the reduction of the ecological fitness at individual level, and hence, a shift in the balance of the ecosystem could be affected without having a critical impact on any one species. To conclude, I summarize the links between climate changes, ecological decision in life history, the revised consequence at individual level, and discuss how the finely-balanced relationship affects biodiversity and population structure.

Consideration on the T-history Method for Measuring Heat of Fusion of Phase Change Materials (PCM의 잠열측정을 위한 T-history법에 대한 고찰)

  • 박창현;최주환;홍희기
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.13 no.12
    • /
    • pp.1223-1229
    • /
    • 2001
  • Though conventional calorimetry methods such as differential scanning calorimetry (DSC) and differential thermal analysis (DTA) are used generally in measuring heat of fusion, T-history method has the advantages of a simple experimental apparatus and no requirements of sampling process, which is particularly useful for measuring thermal properties of inhomogeneous phase change materials (PCMs) in sealed tubes. However, random criteria (a degree of supercooling) used in selecting the range of latent heat release and neglecting sensible heat during the phase change process can cause significant errors in determining the heat of fusion. In the present study, it was shown that a 40% discrepancy exists between the original T-history and the present methods when analyzing the same experimental data. As a result, a reasonable modification to the original T-history method is proposed.

  • PDF

Improvement of the T-history Method to Measure Heat of Fusion for Phase Change Materials

  • Hong, Hi-Ki;Park, Chang-Hyun;Choi, Ju-Hwan;Peek, Jong-Hyeon
    • International Journal of Air-Conditioning and Refrigeration
    • /
    • v.11 no.1
    • /
    • pp.32-39
    • /
    • 2003
  • Though conventional calorimetry methods such as differential scanning calorimetry and differential thermal analysis are used generally in measuring heat of fusion, T-history method has advantages of a simple experimental apparatus and no requirements of sampling process, which is particularly useful for measuring thermophyical properties of in-homogeneous phase change materials in sealed tubes. However, the degree of supercooling used in selecting a range of latent heat release and neglecting sensible heat during the phase change process can cause significant errors in determining the heat of fusion. In the present study, it was shown that a 40% discrepancy exists between the original T-history and the present methods when analyzing the same experimental data. As a result, a reasonable modification to the original T-history method is proposed.

The Effect of Cyclic Loading History on the Creep of $SiC_f/Si_3N_4$ Fiber-reinforced Composite (사이클 하중이력이 $SiC_f/Si_3N_4섬유강화 복합재료의 크리프에 미치는 영향)

  • 박용환
    • Journal of the Korean Society of Safety
    • /
    • v.15 no.4
    • /
    • pp.35-40
    • /
    • 2000
  • The influence of cyclic loading history on the creep behavior of the 30 vol% hot-pressed $SiC_f/Si_3N_4copmposite was experimentally investigated at $1200^{\circ}C$. The duration of loading/unloading had great effects on the creep behaviors. The short term duration cyclic loading history test results showed significant reduction in the primary and steady-state creep rates. For example, 300sec loading/300sec unloading history resulted in 70% lower steady-state creep rate than that of the continuous loading. However the long term duration cyclic loading history test results showed little change in creep rates compared to those of the continuous one. The reason for the significant change in the short term duration cycles was estimated due to the change in the stress redistribution between the fiber and matrix during the creep recovery in the primary stage.

  • PDF

An Experimental Study about the Measurement of the Thermal Properties of Phase Change Materials using T-history method (T-history 방법에 의한 잠열재의 열물성치 측정에 대한 실험적 연구)

  • Kang, Dong-Hoon;Peck, Jong-Hyeon;Park, Seung-Sang;Seo, Tae-Bum
    • Proceedings of the KSME Conference
    • /
    • 2001.06d
    • /
    • pp.226-231
    • /
    • 2001
  • The purpose of this paper is to propose the experimental method of thermal properties of Phase Change Materials (PCMs) by using T-history method. As far, in order to measure the heat of fusion and specific heat of PCMs, conventional thermal analysis methods such as DSC and DTA have been used. Because these methods test very small samples, thermal properties of samples are usually different from those of materials consisting of several components. For these reasons, T-history method, the simple measurement method of the heat of fusion and specific heat of PCMs have been performed. In this paper, we investigated the thermal properties of low temperature PCMs(below $0^{\circ}C$) under the charging process by using T-history method. The results are compared to those of DSC method. The T-history method will be useful for selection of the best PCM from lots of candidates and development of new PCMs.

  • PDF

Various Perspectives to Read the Micro-History of Korean Housing after the Period of Opening the Port (근대 이후 한국주거의 미시사를 보는 다양한 관점)

  • Hong Hyung-Ock
    • Journal of Families and Better Life
    • /
    • v.23 no.5 s.77
    • /
    • pp.79-92
    • /
    • 2005
  • The purpose of this study was to explore the various perspectives to read micro-history of Korean housing after the period of Opening the Port for foreigners. This study were designed to adapt original theory for exploring the unique housing perspectives without using strict basic assumption which were already developed in the area of sociology, history, anthropology and philosophy. Research method applied was literature review. Each perspective might give useful insight to read the micro-history of Korean housing on the way of change after the Period of Opening the Port in Korea. Adapted perspectives to housing history were critical theory perspective, microsociological perspective, everyday life perspective(phenomenology tradition, symbolic interaction tradition, Marxist tradition), discourse perspective, exchange theory perspective, conflict theory perspective, and life course perspective. Conclusively, each perspective must be adapted multi-supportively to read the housing phenomena, because housing change derived from complex causes and factors. The fruit of this study was to ensure the adaptable viewpoint to housing were useful to read the micro-history of housing change.

Accuracy Improvement for Measurement of Heat of Fusion by T-history Method (T-history법에 의한 잠열량 측정 정확도의 향상)

  • 박창현;백종현;강채동;홍희기
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.15 no.8
    • /
    • pp.652-660
    • /
    • 2003
  • T-history method, measuring heat-of-fusion of phase change material (PCM) in sealed tubes, has the advantages of a simple experimental device and no requirements in sampling process. However, a degree of supercooling used in selecting the range of latent heat release and neglecting sensible heat during the phase change process can cause significant errors in determining the heat of fusion in the original method, which has been improved in order to predict better results by us. In the present study, the modified method was applied to a variety of PCM such as paraffin and lauric acid having very small or no supercooling with a satisfactory precision. Also the selection of inflection point and temperature measurement position was fumed out not to affect the accuracy of heat-of-fusion significantly. As a result, the method can provide an appropriate means to assess a new developed PCM by cycle test even if a very accurate value cannot be obtained.

A Study on the Original Form and Change of Dokrak-dang and Gye-jeong (독락당과 계정의 원형과 변화과정 연구)

  • Kim, Dokyoung
    • Journal of architectural history
    • /
    • v.23 no.5
    • /
    • pp.23-36
    • /
    • 2014
  • Source criticism is very important on the research of architectural history as well as general history. In this point this research studied on the original form and change of Dokrak-dang that is very important building in architectural history of Korea. The result is as in the following. Dokrak-dang that Whoijae built at first was three by two kans size that had daecheong of four kans and ondol-bang of two kans. Gye-jeong that Whoijae built was three kans size that had daecheong of two kans and ondol-bang of one kan. After Whoijae died, Dokrak-dang's ondol-bang was changed to maru between 1555 and 1556 and ondol-bang in west side and stack room was added in 1630. Gye-jeong was changed to ㄱ-shaped floor plan that was added up two kans from three kan's 'ㅡ'-shaped one.

A Study on the Curriculum Development for Climate Change and Cultural Heritage (기후변화대응을 위한 문화유산 교육과정 개발 방안 연구)

  • Lho, Kyung-Min
    • Journal of architectural history
    • /
    • v.32 no.3
    • /
    • pp.39-51
    • /
    • 2023
  • This study aims to develop a cultural heritage curriculum for climate change and present educational directions for cultural heritage and climate change impact in the future. In this study, the role and necessity of cultural heritage education for climate change were first discussed based on previous studies on climate change and cultural heritage. Next, the current status analysis of educational cases related to climate change and cultural heritage was conducted based on educational manuals, curriculum, and heritage competency systems associated with climate change. Finally, we propose a plan to develop a curriculum to cope with climate change and cultural heritage for graduate students in higher education institutions based on the four components of developing a curriculum. In future studies, we intend to propose guidelines for designing educational manuals and specific curricula for each educational target to cope with the climate change of cultural heritage presented in this study.