• Title/Summary/Keyword: timber management

Search Result 172, Processing Time 0.02 seconds

Air Tightness Performance of Residential Timber Frame Buildings

  • Kim, Hyun-Bae;Park, Joo-Saeng;Hong, Jung-Pyo;Oh, Jung-Kwon;Lee, Jun-Jae
    • Journal of the Korean Wood Science and Technology
    • /
    • v.42 no.2
    • /
    • pp.89-100
    • /
    • 2014
  • Energy consumption statistics in 2005 from the Korea Energy Management Corporation show that building energy usage was about 24.2% of total domestic energy consumption, and 64% of total building energy usage was consumed by residential buildings. Thus, about 10% of total domestic energy consumption is due to the heating of residential buildings. Building energy can be calculated by the configuration of the building envelope and the rate of infiltration (the volume of the infiltration of outdoor air and the leakage of indoor air), and by doing so, the annual energy usage for heating and cooling. Therefore, air-tightness is an important factor in building energy conservation. This investigate air infiltration and various factors that decrease it in timber frame buildings and suggest ways to improve air-tightness for several structural types. Timber frame buildings can be classified into light frame, post and beam, and log house. Post and beam includes Han-ok (a Korean traditional building). Six light frame buildings, three post and beam buildings, one Korean traditional Han-ok and a log house were selected as specimens. Blower door tests were performed following ASTM E779-03. The light frame buildings showed the highest air-tightness, followed by post and beam structures, and last, log houses.

A Case Study for Applying Linear Programming to Analyze The Effects of The Desired Future Conditions for Forest Functions on Forest Management (산림기능별 목표임상 조건이 산림경영에 미치는 영향분석을 위한 선형계획기법 적용 연구)

  • Jang, Kwangmin;Won, Hyun-Kyu;Seol, A Ra;Chung, Joosang
    • Journal of Korean Society of Forest Science
    • /
    • v.98 no.3
    • /
    • pp.247-254
    • /
    • 2009
  • In this study, linear programming was applied to a case study in Gwangreung Experimental Forest of Korea Forest Research Institute investigating the effect of the desired future conditions on forest management. Considering the social, economic and ecological demands of people from the forest, the forest functions were classified into four including natural conservation, timber production, water yield and scenic conservation. The forest land areas were divided into four-types of forest functional zones and forest management prescriptions including the desired future conditions by the forest function type were established. The Model II linear programming was used in optimizing the forest management planning. The model includes management policies, as the constraints, for non-declining yield, allowable cutting area, allowable % age class distribution and allowable % species allocation as well as the land and other accounting regimes. Maximization of timber production was used the objective function. Based on the Model II formulations, the effects of the desired future conditions by the forest function type on forest management planning were investigated in terms of timber production, net present value and stand structures over time.

Social and Economic Effects of Forest Management Certification: a Case of Jeju Experimental Forest (산림경영인증의 사회·경제적 효과 분석: 제주시험림의 사례)

  • Lee, Seong Youn;Lee, Ho Sang;Chung, Young Gyo;Joo, Rin Won
    • Journal of Forest and Environmental Science
    • /
    • v.28 no.4
    • /
    • pp.254-262
    • /
    • 2012
  • The purposes of the research in related to FSC in JuJe experimental forests (JJEFs) is to make pre and post socio-economic comparisons and play an important role of FSC, and recognition change to FSC timbers and to make an analysis to consumers' needs. As the results of onsite survey in 2005, respondents show a high awareness of SFM and FSC in comparisons of 2004, and the JJEFs play a critical role to make SFM and FSC advertisement worldwide, such as consumers' satisfaction to SFM and FSC is high. Hence provision of JJEF information such as job creation and socio-economic impacts to stockholders could make their satisfaction improving. Most of respondents to the FSC of JJEF represent a positive rate while low awareness to FSC timber is represented. Therefore, necessary information about JJEF FSC with forest management, process and consumption pattern of FSC is required into citizens. The final results prove that FSC effects such as 1.3 billion won direct additional benefits in terms of socio-economic aspects including environmental benefits and job creation and economic effects are enough to offset 1.3 billion won additional costs.

Determination of Forest Road Construction Priority Order Using Multiple Criteria Decision Making Methods (다기준의사결정법(多基準意思決定法)에 의한 임도개설순위(林道開設順位)의 결정(決定))

  • Cha, Du Song;Cho, Koo Hyun;Kim, Jong Yoon
    • Journal of Korean Society of Forest Science
    • /
    • v.85 no.2
    • /
    • pp.149-157
    • /
    • 1996
  • The applications of multiple criteria decision making(MCDM) methods were investigated to determine the priority order in forest road construction for timber harvesting and silvicultrual activities in 22 regions. In this paper, MCDM methods have five methods from two kinds of models. The one is non-compensatory preference model including maximin and maximax method; the other is compensatory preference model including simple additive weighting method(SAW), hierarchical additive weighting method(HAW) and technique for order preference by similarity to ideal solution(TOPSIS), SAW and TOPSIS methods turned out to be the most adequate for forest road construction priority order among the five methods tested in this study.

  • PDF

Improvement of the Thinning System by Exploring the Stand Density Management Criteria for Chamaecyparis obtusa in South Korea (편백림의 임분밀도 관리 기준 탐색을 통한 시업체계 개선)

  • Su Young Jung;Kwang Soo Lee;Hyun Soo Kim;Joon Hyung Park
    • Journal of Korean Society of Forest Science
    • /
    • v.113 no.1
    • /
    • pp.131-142
    • /
    • 2024
  • The purpose of this study was to estimate the optimal stand density criteria for each growth stage of Chamaecyparis obtusa (Siebold & Zucc.) Endl. to achieve the timber production goal for cypress forests and develop an optimal silvicultural system for forest thinning. A relative yield index (Ry) value of 0.75, presented as a stand density management criterion index, was estimated by analyzing the relationship characteristics between the composition ratio and stand density of slender trees from 216 sample plots of the recruited cypress forests. The analysis of the feasibility of achieving each production target in the existing silvicultural system for C. obtusa revealed that the growth rate according to the parameters of forest land productivity, such as site index and thinning intensity according to the increase in age, was not properly reflected. In the thinning system for each timber production target analyzed in this study, 353 high-quality large hardwoods from 498.1 m3/ha, 703 high-quality medium hardwoods from 376.2 m3/ha, and 1,758 small-diameter hardwoods from 249.5 m3/ha could be harvested. Although the silvicultural system prepared on the basis of the results of this study cannot be uniformly applied according to various management goals, this study is meaningful in that it presents empirical reference standards based on the stand density management diagram that reflects the growth characteristics of cypress forests in South Korea.

Application of Fuzzy Linear Programming to Estimate the Potentiality of Domestic Long-Term Wood Supply (국내 장기목재공급 잠재력 예측을 위한 퍼지선형계획법의 적용)

  • Won, Hyun-Kyu;Kim, Young-Hwan;Lee, Kyeong-Hak;Jang, Kwang-Min
    • Journal of Korean Society of Forest Science
    • /
    • v.99 no.6
    • /
    • pp.802-807
    • /
    • 2010
  • The objective of this study was to estimate potential of domestic long-term wood supply by using fuzzy linear programming (FLP). In order to construct a numerical formula model, maximization of total timber production was used for the objective function. Size limit of harvesting and sustained yield were used as the constraints. The results of comparison between LP and FLP were shown that LP is more suitable than FLP in terms of the amount of timber production and final forest stock. However, as long-term sustained yield was limitedly achieved by using LP, FLP was more desirable for prediction of potential wood supply. According to the results of this study, the potential of annual domestic wood supply was estimated about 10.5 million cubic meters. Gyeong buk, Jeon nam, Gangwon and Gyeong nam province were highly ranked in order of provincial potential of wood supply.

A Study on Status Investigation and Improvement for Safety Management of Zipline(I) (짚라인의 안전관리 실태와 개선방향에 관한 연구(I))

  • Kim, Eui Soo
    • Journal of the Korean Society of Safety
    • /
    • v.34 no.2
    • /
    • pp.15-21
    • /
    • 2019
  • Recently, the number of facilities and users of zipline which is the most popular among extreme leisure facilities has been increasing year by year. Zipline is a means of transporting durable wire between two timber or stay and moving the trolley connected to the passenger at high speed in the opposite direction. However, due to the nature of the zip line facility, the risk of accidents is always present and safety accidents are frequently occurring. Therefore, this study investigates the current state of safety management and extract the problem in terms of safety management through analyzing the installation state of zipline facilities in the case of accidents and reviewing of similar facility regulations. In order to solve this problem, we will contribute to establishment of comprehensive and systematic countermeasures and establishment of safety improvement system by suggesting measures to improve safety management through analyzing foreign regulations and safety management regulations for zipline and other extreme leisure facilities.

A Study on the Management Method in Accordance with the Vegetation Structure of Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin (울진 소광리 금강소나무림 식생구조 특성에 따른 관리방안)

  • Kim, Dong-Wook;Han, Bong-Ho;Park, Seok-Cheol;Kim, Jong-Yup
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.50 no.1
    • /
    • pp.1-19
    • /
    • 2022
  • The Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin has traditionally been a pine tree protection area (prohibited forest) for timber production purposes, and is now designated and managed as a protected area for forest genetic resource conservation by the Korea Forest Service. This study, we analyzed topographical characteristics, existing vegetation, tree age, and plant community structure, and proposed a sustainable management method for the Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin for timber havesting purposes. The topographical characteristics of the target area were 36.7% ridges and 38.7% valleys; the ratio of ridges to valleys was similar, and the slopes formed 24.7% of the total area. The types of pine forest communities are divided into six types based on the progress of pine forest renewal, the competition with other species such as deciduous broadleaf trees, and the formation of layered structures. It has been confirmed that the age of the large-diameter pine trees (40~60cm in diameter) is approximately 60~70 years, which is relatively low. As a result of the analysis of the relative importance percentage and layered structure, differences depended on the progress of the pine forest renewal project, and not only the maintenance of the pine forest, but also the creation of a secondary growth forest, the density adjustment of pine trees, and the active management of competitive trees. The average basal area by the community was 12,642.1~25,424.4cm2 for the tree layer and 1.8~1,956.5cm2 for the low tree layer based on a quadrat of 400m2. The difference in the basal area appeared to depend on the size and number of trees forming the tree layer and the degree of pine forest renewal (the degree of time elapsed after thinning pine trees). The average number of species that appeared in each community was 8.7-20.3; there were many species located in valleys, and the type competes with deciduous broadleaf trees due to the lack of management. The diversity of species ranged from 0.6915-1.0942, and was evaluated as low compared to pine communities in central temperate zones. In this paper, we determined the management goals of Geumgang Pine (Pinus densiflora) Forest in Sogwang-ri, Uljin to produce timber with high economic value, and suggested efficient vegetation management for continuous afforestation, the establishment of a timber production system, and improvement of wood production as a management direction.

The Application of Various Forest Resource Planning Models to Forest Management in Korea -Model I vs. Model II- (삼림경영계획(森林經營計劃)모델의 적용성연구(適用性硏究) -Model I 대 Model II-)

  • Kwon, O Bok;Chang, Cheol Su
    • Journal of Korean Society of Forest Science
    • /
    • v.77 no.4
    • /
    • pp.389-400
    • /
    • 1988
  • The recent trend in multiple-use land management planning is using Model I and Model II formulations designed for timber activity scheduling problems. Numerous models hate been developed, with MUSYC(Johnson and Jones, 1979) being the first to incorporate both model structures. Currently the most popular computer program using both Model I and Model II is FORPLAN(Johnson and others, 1986). A Model I formulation requires fewer rows and provides more direct information on what happens to an acre from rotation to rotation. In some problems, Model II provides a much more compact problem matrix with much fewer columns and only a moderate increase in row number. In this paper we examined and evaluated their usefulness in comprehensive multiresource forest management planning.

  • PDF

Effects of Postfire Logging on Bird Populations and Communities in Burned Forests (산불 발생 지역의 피해목 벌채에 따른 조류 개체군과 군집의 변화)

  • Choi, Chang-Yong;Lee, Eun-Jae;Nam, Hyun-Young;Lee, Woo-Shin
    • Journal of Korean Society of Forest Science
    • /
    • v.96 no.1
    • /
    • pp.115-123
    • /
    • 2007
  • We investigated the effects of postfire logging on bird populations and communities through 57 point counts in unburned, burned and logged burned plots of coniferous forests in Samcheok, Korea. We found that lower species richness, abundance, and diversity in logged plots where were controlled by a typical postfire management. As results of guild analysis for nest sites and food resources, postfire logging reduced densities of ground-shrub nesters, primary and secondary cavity nesters, but was also related to reduction in densities of some foraging groups such as timber drillers and foliage searchers. These results suggest that snag-retention is essential for birds in burned forests and that postfire logging is incompatible with the maintenance of bird populations and communities. Consequently we need to develope guidelines of postfire management for snag-retention in burned forests through intensive researches focused on some target species such as Great spotted woodpeckers Dendrocopos major.