• Title/Summary/Keyword: change of composition

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Analyzing the Impacts of Climate Change on Forest Composition in Korea (산림의 임상구조 결정요인 분석과 기후변화에 따른 임상구조 변화 예측)

  • Lee, Honglim;Kwon, Oh Sang
    • Environmental and Resource Economics Review
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    • v.26 no.2
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    • pp.229-255
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    • 2017
  • This study empirically estimates the impacts of climate change on forest composition in Korea using a fractional data regression model, and forecasts the change in forest composition in the 2040s and 2090s based on the IPCC climate change scenarios. Unlike the forest science studies that incorporate mostly only ecological variables as the determinants of forest composition, we take into account regional level socio-economic and forest management variables as well. Our estimation results found that not only environmental factors but also socio-economic and forest management related factors strongly affect the composition of Korean forest. Based on the estimation results and IPCC scenarios on climate change, we predict that the share of currently dominant coniferous forest will decline in the future under all scenarios. About 10% of total forest area is likely to be converted from coniferous forest into broadleaved forest until 2090s under the scenario RCP 8.5. It is also predicted that there will be a substantial regional variation in the effects of climate change on forest composition, and the coniferous forests in the inland regions will decline more dramatically.

Post-Reclamation Long-term Changes in Fish Species Composition of Beach Seine Samples in Cheonsu Bay (천수만 방조제 건설 후 대천 해빈 천해 어류의 중장기 종조성 변화)

  • Kwon, Soon Yeol;Hwan, Hak Bin;Hong, Ji Min;Lee, Tae Won
    • Ocean and Polar Research
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    • v.42 no.2
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    • pp.141-155
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    • 2020
  • Species composition of fish in the shallow water at Daecheon beach was determined using monthly beach seine samples collected from April 2010 to March 2011. These data were compared with the previous data, one just after reclamation in 1984-1985, and the other in 1995-96, in order to assess the post-reclamation impact of the environmental change on the fish assemblage. A total of 30 species from 1,464 individuals with biomass of 17,808 g were identified. Dominant species in the number of individuals were Chelon haematocheilus (49.3%), Takifugu niphobles (13.7%) and Paralichthys olivaceus (10.0%). Among pelagic fish, migrant juvenile fish such as Sardinella zunasi and Thryssa kammalensis were abundantly collected in 1984-85, but the catch amount was gradually decreased as time untill only few pelagic fish were collected in 2010-2011. The benthic fish were most abundant in 1984-1985 among habitat groups, and Favonigobius gymnauchen and Kareius bicoloratus were the top two predominants. Species composition of benthic fish did not exhibited drastic changes in 1995-1996, but both the abundance decline and the species composition change was evident in 2010-2011. Among the semi-benthic fish from 1984-1985 samples, Sillago japonica and Konosirus punctatus predominated. Species composition was slightly changed in 1995-1996, but significant changes were met in 2010-2011 with the two predominats, Chelon haematocheilus and Takifufu niphobles. These changes in fish species composition may reflect the post-reclamation effect of the impaired water quality and the accumulation of organic rich fine sediments.

Study of Weld Part Status Change by $CO_2$ Welding According to the Variation of Gas Composition and Welding Wire on SS400 Material (가스성분 및 용접와이어의 변화에 따른 SS400소재의 $CO_2$용접에서 용접부의 상태변화 고찰)

  • Kim, Bub-Hun;Kim, Won-Il;Choi, Chang;Park, Yong-Hwan
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.11 no.5
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    • pp.129-136
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    • 2012
  • On this study, $CO_2$ gas, net of Ar gas, and mixed gas in solid wire(AWS ER 70S-6) and flux cored wire(AWS E71T-1) were used to weld on Mild steel(SS400). After the progress, the status changes of the welds in Mild steel(SS400) were investigated with compositional changes. For stable experiments, welding was conducted using the automatic feeder. Radiation testing, hardness testing, chemical composition analysis and penetrated cross-section were measured. Through these experiments, shapes of penetrated cross-section, chemical composition changes, and weld defects according to the variation of welding gas were known. Weld defects and weld cross-sectional shapes by the variation of the welding voltage were also detected.

The Effects of Neuromuscular Re-education on Physical Composition, Body Water, and Functional Independence in Stroke Patients (신경근 중재 접근이 뇌졸중 환자의 신체조성, 체수분 및 기능적 독립성에 미치는 영향)

  • So, Kyoung-Suk;Shin, Hong-Cheul;Kang, Jeong-Il
    • The Journal of Korean Physical Therapy
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    • v.18 no.1
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    • pp.11-31
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    • 2006
  • Purpose: The purpose of this study is to investigate the effect of neuromuscular re-eduction program and traditional intervention program. Methods: It is focused on difference between changes of experimental before and after on 30 stroke patient's physical composition, body water and functional independence. Results: The obtained results are as follows ; 1. In the comparison of change in physical composition between the experimental group and control group, the between-subjects factors were not a significant difference. 2. In the comparison of change in body water between the experimental group and control group, the between-subjects factors were not a significant difference. 3. In the comparison of change in functional independence between the experimental group and control group, the between-subjects factors were a significant difference in 8 items and total FIM (p<0.01; p<0.05) but, were not a significant difference in 11 items. Conclusion: the neuromuscular re-eduction program was more effect then traditional intervention program in functional independence but, was not a significant difference in body composition and body water.

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환경적 스트레스에 의한 Helicobacter pylori의 형태 변화

  • 이학성;최태부
    • Microbiology and Biotechnology Letters
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    • v.25 no.3
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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.

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A Study on the Use and Spatial Composition of Outpatient Department of Psychiatry in General Hospital (종합병원 외래진료부문 정신건강의학과의 공간구성 및 이용현황에 관한 연구)

  • Moon, Ha Ni;Noh, Jai Sung;Chai, Choul Gyun
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.21 no.1
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    • pp.17-26
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    • 2015
  • Purpose : This study examined the social and environmental change in the outpatient department of psychiatry, were analyzed disease characteristics and using characteristics of the mental illness. Thus, this aims to provide a material that can be used for efficient spatial composition of psychiatry. Methods : This study was conducted through a literature review, observation surveys, interviews. Results : Psychiatry is aware of the need to respond to the current needs of ambulatory space, there are concerns that the spatial configuration for your needs. In accordance with the results of studies conducted are as follows: 1) Specialty care programs and space needs based on segmentation and specialization of the disease 2) Considered in conjunction with the layout of essential space and other departments 3) Spatial composition and furnishings for characteristic of psychiatry 4) Spatial configuration taking into account the patient's characteristic. Implications : This study looked at the change of social change and the environment related to psychiatry. Grasp the present state of spatial composition in psychiatry. And the use characteristics of patients and guardians were investigated. Meanwhile, studies of psychiatric outpatient department is still lacking. As a result, its significance is to analyze the spatial composition requirements.

Effect of Chemical Composition on the Microstructure and Tensile Property in TRIP-assisted Multiphase Steels (TRIP형 복합조직강의 미세조직 및 인장성질에 미치는 화학조성의 영향)

  • Lee, K.Y.;Jang, W.Y.;Kang, J.W.
    • Journal of the Korean Society for Heat Treatment
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    • v.16 no.3
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    • pp.127-133
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    • 2003
  • The effect of chemical composition on the microstructural change and tensile property in TRIP-assisted steels with different chemical composition was investigated by using SEM, TEM, XRD and UTM. As a result of microscopic observation, the morphology of retained austenite could be identified as two types; a granular type in a steel containing higher Si and a film type in a steel having higher C. For the case of higher C-containing steel with a tensile strength of 860 MPa and a total elongation of 38%, film-typed retained austenite could be observed between lath bainitic ferrite. Actually, metastable retained austenite was a requisite for the good formability, which means that chemical composition plays a significant role in the microstructure and tensile property of TRIP-assisted steels. With respect to tensile property, the steels containing suitable Si and Mn, respectively, showed a typical TRIP effect in stress-strain curve, while a steel containing higher Mn content exhibited the similar behavior shown in dual phase steel.

Effect of Chemical Composition on Tensile Property in TRIP-assisted Multiphase Steel for Automobile Structure (차량구조용 변태유기소성(TRIP)형 복합조직강의 인장성질에 미치는 화학조성의 영향)

  • Lee, Ki-Yeol;Bang, Il-Hwan;Ma, Ah-Ram;Kim, Young-Sun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.15 no.3
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    • pp.106-113
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    • 2007
  • The effect of chemical composition on the microstructural change and tensile property in TRIP-assisted steels with different chemical composition was investigated by using SEM, TEM, XRD and UTM. As a result of microscopic observation, the morphology of retained austenite could be identified as two types : a granular type in a steel containing higher sillicon and a film type in a steel having higher carbon. For the case of higher carbon-containing steel with a tensile strength of 860 MPa and a total elongation of 38%, film-typed retained austenite could be observed between lath bainitic ferrite. Actually, metastable retained austenite was a requisite for the good formability, which means that chemical composition plays a significant role in the microstructure and tensile property of TRIP-assisted steels. With respect to tensile property, the steels containing suitable silicon and manganese, respectively, showed a typical TRIP effect in stress-strain curve, while a steel containing higher manganese content exhibited the assimilar behavior shown in dual phase steel.

International Comparison of Food Composition Table (한국, 미국, 일본의 식품성분표 비교)

  • 최정숙;전혜경;박홍주
    • The Korean Journal of Community Living Science
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    • v.12 no.2
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    • pp.119-135
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    • 2001
  • This study was conducted to compare the composition table of Korean food with that of foreign food. Analysis was made for Korean food composition table($5^{th}$ revision), Korean food composition table in Appendix of Recommended Dietary Allowances for Korean(6$^{th}$ th/ edition), Standard tables of food composition in Japan($5^{th}$ revised edition) and USDA Composition of Foods - Raw, Processed, Prepared. The method of content analysis was applied for this study and such differences were pointed out as the classification of food items, food items enlisted, the content unit of food and food components presented etc. To improve Korean food composition table, new food items and components should be added and old food items be eliminated based on the change of people's food consumption pattern. Also analysis for the domestic foods consumed by local people should be accomplished rather than borrowing foreign country's data.

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A Study on Revision Direction of Korean Food Composition Table Through International Comparison (국제비교를 통한 우리나라 식품성분표의 개정방향에 대한 연구)

  • 김은영
    • Journal of Nutrition and Health
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    • v.27 no.2
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    • pp.192-206
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    • 1994
  • This study was conducted to find out the weak points of present Korean food composition table, so that to suggest the revision direction. Korean food composition table in Appendix of Recommended Dietary Allowances for Korean, 5th edition, was analyzed by comparing with 6 other food composition tables such as one other Korean food composition table, and those of Japan(two), U.S.A., East Asia and Near East. The content analysis was applied as the method of this study. As result, many drawbacks like classification of food components, etc. were pointed out. The best solution to improve these drawbacks in present food composition table is establishing on organization entirely in charge of food composition table. In this way the organization can carry out food analysis systematically and continuously. Then new food items can be added, old food items be eliminated based upon people's food consumption pattern change. Also we need to analyze our own foods consumed by our people instead of borrowing the other country's data.

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