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A Study on the Environmental Assessment for Regional-Based Green Area Conservation (지역단위 녹지 확보를 위한 환경성평가방안 연구)

  • Oh, Seung-Ryun;Kang, Seon-Hong;Lee, Chun-Won
    • Journal of Korean Society of Water and Wastewater
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    • v.25 no.4
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    • pp.535-546
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    • 2011
  • The study area investigated in this research is Hwaseong city, Gyeonggi-Do where small scale development is currently in progress. For the last three years, we carried out the environmental and ecological assessment by using data from The Ministry of Environment and Han River Basin Environmental Office. Most of development works in Hwaseong city, Gyeonggi-Do are small scale developments which are related with factory and distribution complex based on individual laws and regulations. However, environmental and ecological assessment is not being sufficiently reflected beforehand. Especially, because the development takes place mainly in the outskirts of the city, the fine forest is continuously being damaged. We analyzed changes in green zone area caused by the developments. As a result, the percentage of original green zone was decreasing while the percentage of artificial green zone was increasing. We should maintain the percentage of the original green zone in order to conserve natural environment. In the past three years, the damage of the DGN (Degree of Green Naturality) 7 area that has high conservative value was little, but, there was serious damage in the area of DGN 6. In order to conserve natural environment, political and institutional investigation should be seriously carried out for mitigation of environmental and ecological damages.

Performance of Northern Exposure Index in Reducing Estimation Error for Daily Maximum Temperature over a Rugged Terrain (북향개방지수가 복잡지형의 일 최고기온 추정오차 저감에 미치는 영향)

  • Chung, U-Ran;Lee, Kwang-Hoe;Yun, Jin-I.
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.9 no.3
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    • pp.195-202
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    • 2007
  • The normalized difference in incident solar energy between a target surface and a level surface (overheating index, OHI) is useful in eliminating estimation error of site-specific maximum temperature in complex terrain. Due to the complexity in its calculation, however, an empirical proxy variable called northern exposure index (NEI) which combines slope and aspect has been used to estimate OHI based on empirical relationships between the two. An experiment with real-world landscape and temperature data was carried out to evaluate performance of the NEI - derived OHI (N-OHI) in reduction of spatial interpolation error for daily maximum temperature compared with that by the original OHI. We collected daily maximum temperature data from 7 sites in a mountainous watershed with a 149km2 area and a 795m elevation range (6511,445m) in Pyongchang, Kangwon province. Northern exposure index was calculated for the entire 166,050 grid cells constituting the watershed based on a 30-m digital elevation model. Daily OHI was calculated for the same watershed ana regressed to the variation of NEI. The regression equations were used to estimate N-OHI for 15th of each month. Deviations in daily maximum temperature at 7 sites from those measured at the nearby synoptic station were calculated from June 2006 to February 2007 and regressed to the N-OHI. The same procedure was repeated with the original OHI values. The ratio sum of square errors contributable by the N-OHI were 0.46 (winter), 0.24 (fall), and 0.01 (summer), while those by the original OHI were 0.52, 0.37 and 0.15, respectively.

Characterization and Properties of Composites of Woodflour and Polylactic Acid

  • Febrianto, Fauzi;Yoshioka, Mariko;Nagai, Yuko;Syafii, Wasrin;Shiraishi, Nobuo
    • Journal of the Korean Wood Science and Technology
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    • v.34 no.5
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    • pp.67-78
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    • 2006
  • Modification of polylactic acid (PLA) and 10% maleic anhydride (MAH) with 15% dicumyl peroxide (DCP) based on MAH weight was conducted in the kneader at 160C and 30~70 rpm, for 15 min. The resulting MAH-modified PLA (PLA-MA) was then evaluated as a compatibilizer for PLA-wood flour (WF) composites. The FTIR and 1H-NMR analysis gave evidence of PLA-MA formation. After kneading and reacting with MAH and DCP, the number (Mn) and the weight average (Mw) molecular weights of PLA decreased as compared to the original PLA. The presence of WF in the composites decreased the tensile strength and several other physical properties. The higher the WF loading resulted in the greater the reduction of tensile strength. An addition of 10% PLA-MA as a compatibilizer to the composites improved the tensile strength and several other physical properties, increased the flow temperature, and decreased the melt viscosity. The improved composite revealed 1.42 times increased in tensile strength but not over PLA alone, and absorbed considerably less water compared to those of the composites free-compatibilizer.

The Effects of Multiple Recycling on Deinkability and Properties of Recycled Paper

  • Shin, Jun-Seop;Cho, Hern-Joung
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 1999.04b
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    • pp.361-365
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    • 1999
  • This study examined the effects of multiple recycling on deinkability and properties of recycled paper from laser computer printout (LCPO). First, alkaline paper with a 20% printed area was disintegrated by TAPPI standard disintegrator at room temperature. After dewatering, the pulp was flotated and dried in oven at80C for 24 hrs. A sequence of wetting, disintegrating, flotating and drying was one recycling cycle and this cyclic treatment was repeated from zero to five times. The recycled handsheet dropped to 90% of the original brightness after five cycles, and lost the most brightness after five cycles, and lost the most brightness in the first two cycles. However, it had a gain of 10% in opacity after five cycles as the same as the case of nonprinting. And, in this study, the method for determining residual ink(toner) content in recycled handsheets ere established by means of SEM-EDX and Py-GC. The change of residual ink percentage on recycled paper showed the effect of recycling numbers on deinkability of waste paper. A slight decrease in deinkability was noted for the recycled handsheets, which may be due to the change of fiber surface free energy connected with fiber swelling.

A Study on the Poverty of Mountain People Depending on Forests

  • NGUYEN, Phuong Thi Minh;NGUYEN, Song Van;DO, Duc Tai;NGUYEN, Quynh Thi Thuy;DINH, Thanh Trung;NGUYEN, Hang Phan Thu
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.7
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    • pp.519-529
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    • 2020
  • Livelihood capitals have a clear influence on livelihood development. As for the livelihood results, it has been pointed out in the analysis of the poor households that the ability of people to escape poverty depends especially on the access to livelihood capitals. This study aims to analyze the impacts of livelihood capital on poverty among mountain people who depend on forests through human capital, social capital, natural capital, physical capital and financial capital. This research employs the model of binary regression function. Independent variables x1, x2, …, xn are targets of livelihood strategy, vulnerability context, and livelihood capitals. These variables were selected to be included in the original model with dependent variable Y as poor and non-poor households. This study surveys households living in upland areas, near forests, and households of ethnic minorities. The results show that,out of the poor household rate, nearly 4% are newly-poor households or those falling back into poverty. Therefore, the government needs to pay more attention to this disadvantaged group and implements policies such as education and training policies, credit support policies, policies to support forest development, and payment for forest environmental services in the context of emerging countries like Vietnam.

Effects of Temperature and Relative Humidity on the Physical Properties of Electronic Copying Paper (온·습도 조건이 전자 복사용지의 물리적 특성에 미치는 영향)

  • Kang, Kwang-Ho;Kim, Hyoung-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.44 no.3
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    • pp.70-78
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    • 2012
  • For evaluating the printing suitability of electronic copying papers in the aspect of climate conditions, 12 samples of copying papers being generally used in Korea and worldwide were collected. The copying papers were controlled by various temperature and humidity options in conditioning equipment in order to simulate the specific circumstances of dry, temperate or tropical climate, and the pre-heating system of photocopying machines during printing. As results, some copying papers showed several physical problems, especially in recycled copying papers and a normal paper with original printing faulty. These problems of copying papers were mostly resulted in extremely high moisture circumstance, and in lower levels of tensile strength and tensile stiffness. The moisture contents of copying papers during passing through the pre-heater system of photocopying machine could be rapidly decreased because paper is exposed to high temperature around the pre-heating zone. The copying paper, for example of XR3 sample, containing low moisture contents below 2% had high exfoliating possibility of toner transfer from copying paper.

Landuse and Landcover Change and the Impacts on Soil Carbon Storage on the Bagmati Basin of Nepal

  • Bastola, Shiksha;Lim, Kyuong Jae;Yang, Jae Eui;Shin, Yongchul;Jung, Younghun
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.12
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    • pp.33-39
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    • 2019
  • The upsurge of population, internal migration, economic activities and developmental works has brought significant land use and land cover (LULC) change over the period of 1990 and 2010 in the Bagmati basin of Nepal. Along with alteration on various other ecosystem services like water yield, water quality, soil loss etc. carbon sequestration is also altered. This study thus primary deals with evaluation of LULC change and its impact on the soil carbon storage for the period 1990 to 2010. For the evaluation, InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) Carbon model is used. Residential and several other infrastructural development activities were prevalent on the study period and as a result in 2010 major soil carbon reserve like forest area is decreased by 7.17% of its original coverage in 1990. This decrement has brought about a subsequent decrement of 1.39 million tons of carbon in the basin. Conversion from barren land, water bodies and built up areas to higher carbon reserve like forest and agriculture land has slightly increased soil carbon storage but still, net reduction is higher. Thus, the spatial output of the model in the form of maps is expected to help in decision making for future land use planning and for restoration policies.

Outstanding Pinkish Brown-Spored Neotropical Boletes: Austroboletus subflavidus and Fistulinella gloeocarpa (Boletaceae, Boletales) from the Dominican Republic

  • Gelardi, Matteo;Angelini, Claudio;Costanzo, Federica;Ercole, Enrico;Ortiz-Santana, Beatriz;Vizzini, Alfredo
    • Mycobiology
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    • v.49 no.1
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    • pp.24-45
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    • 2021
  • The occurrence of Austroboletus subflavidus and Fistulinella gloeocarpa is documented from the Dominican Republic. The latter species is reported for the first time outside its original locality in Martinique, extending the geographic range for this uncommon pinkish-spored bolete. A detailed morphological description is provided for each species and accompanied by color pictures of fresh basidiomes in habitat and line drawings of the main anatomical features. Both species represent independent lineages within their respective genera based on phylogenetic inference. In addition, A. subflavidus clusters in a sister lineage to the core Austroboletus clade (Austroboletus clade I) here named as Austroboletus clade II. In order to confirm the accuracy of species identification, their identity and relationships were subjected to multilocus phylogenetic analyses of three gene markers (ITS, nrLSU, RPB2) including genetic material already available in public databases. Austroboletus subflavidus is a widely distributed species in North and Central America, whereas F. gloeocarpa is apparently highly localized and seems to appear sparingly in the Dominican Republic, Martinque, and southern Florida. Comparisons with morphologically similar and molecularly inferred allied species are also presented and discussed.

Comparison of Performance Factors for Automatic Classification of Records Utilizing Metadata (메타데이터를 활용한 기록물 자동분류 성능 요소 비교)

  • Young Bum Gim;Woo Kwon Chang
    • Journal of the Korean Society for information Management
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    • v.40 no.3
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    • pp.99-118
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    • 2023
  • The objective of this study is to identify performance factors in the automatic classification of records by utilizing metadata that contains the contextual information of records. For this study, we collected 97,064 records of original textual information from Korean central administrative agencies in 2022. Various classification algorithms, data selection methods, and feature extraction techniques are applied and compared with the intent to discern the optimal performance-inducing technique. The study results demonstrated that among classification algorithms, Random Forest displayed higher performance, and among feature extraction techniques, the TF method proved to be the most effective. The minimum data quantity of unit tasks had a minimal influence on performance, and the addition of features positively affected performance, while their removal had a discernible negative impact.

Evaluation performance of machine learning in merging multiple satellite-based precipitation with gauge observation data

  • Nhuyen, Giang V.;Le, Xuan-hien;Jung, Sungho;Lee, Giha
    • Proceedings of the Korea Water Resources Association Conference
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    • 2022.05a
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    • pp.143-143
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    • 2022
  • Precipitation plays an essential role in water resources management and disaster prevention. Therefore, the understanding related to spatiotemporal characteristics of rainfall is necessary. Nowadays, highly accurate precipitation is mainly obtained from gauge observation systems. However, the density of gauge stations is a sparse and uneven distribution in mountainous areas. With the proliferation of technology, satellite-based precipitation sources are becoming increasingly common and can provide rainfall information in regions with complex topography. Nevertheless, satellite-based data is that it still remains uncertain. To overcome the above limitation, this study aims to take the strengthens of machine learning to generate a new reanalysis of precipitation data by fusion of multiple satellite precipitation products (SPPs) with gauge observation data. Several machine learning algorithms (i.e., Random Forest, Support Vector Regression, and Artificial Neural Network) have been adopted. To investigate the robustness of the new reanalysis product, observed data were collected to evaluate the accuracy of the products through Kling-Gupta efficiency (KGE), probability of detection (POD), false alarm rate (FAR), and critical success index (CSI). As a result, the new precipitation generated through the machine learning model showed higher accuracy than original satellite rainfall products, and its spatiotemporal variability was better reflected than others. Thus, reanalysis of satellite precipitation product based on machine learning can be useful source input data for hydrological simulations in ungauged river basins.

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