• 제목/요약/키워드: forest gap

검색결과 147건 처리시간 0.025초

단판 적층성형 학생용 책상.의자의 제조적성 (Feasibility of Manufacturing Desk and Chair with Curved Veneer Lamination)

  • 서진석;박종영;한기만
    • 한국가구학회지
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    • 제16권2호
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    • pp.59-65
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    • 2005
  • As physical condition of students improves, there is a need to develop human body-friendly desk and chair for students. In this study, desks and chairs were manufactured with curved veneer lamination under high frequency heating and pressing, using ten wood species such as Japanese red pine, Korean pine, pitch pine, Japanese larch, yellow poplar, black locust, oak, radiata pine, beech, and birch. The performance of these products were evaluated. The results obtained were summarized as follows; With high frequency heating, the turned lamination of veneers with full size sheet ($3{\times}6\;feet$) prepared by rotary lathe peeling was successfully applied for making the members of desk top, leg frames of desk and chair. Bending strengths of desk tops were relatively greater for yellow poplar, black locust and red pine, which were similar to those of beech and birch. Bending strengths of desk legs were classified into greater species group (red pine, yellow poplar, larch) and lower species group (radiata pine, Korean pine, pitch pine). Compressive strengths of chair legs in parallel direction to the lamination were greater in black locust and larch. On the other hand, differences between outer and inner gap at the top and drawer bottom of desk top were rather larger for the laminations of birch and beech, and less for those of yellow poplar and pitch pine, showing greater stability of open drawer space. In results, yellow poplar, larch, pitch pine and red pine showed good appearance and strength properties at the curved veneer lamination. Accordingly, it was believed that these domestic woods were able to substitute for birch which was being imported for the use of veneer-laminates type furniture.

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도시녹지 미세먼지 조절 서비스 수요와 공급의 공간적 차이 분석 - 수원시를 대상으로 - (Spatial Analysis on Mismatch Between Particulate Matter Regulation Services Supply and Demand in Urban Area - A Case Study of Suwon -)

  • 강다인;권혁수;최태영;박찬;김성훈
    • 한국환경복원기술학회지
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    • 제24권2호
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    • pp.57-69
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    • 2021
  • Urban green spaces supply ecosystem services (ESs), which are consumed by city residents and generate demand, to improve air quality. It is important to determine supply and demand for ESs and reduce the gap for efficient management. This study proposed a method to use the concept of supply and demand for ESs in the decision-making process for urban planning or management. PM10 concentrations were converted to weight for demand assessment on PM10 reduction, and PM10 absorption capacity of all green spaces including the forests, and that of urban green spaces excluding forests, was calculated for each supply assessment. The differences in the calculated supply and demand were analyzed to derive the mismatched regions in Suwon. As a result, regions with big forested areas showed sufficient supply, indicating that the degree of mismatch among administrative neighborhoods (dong) varied greatly depending on whether they had a forest. An analysis of only urban green spaces showed that all neighborhoods lacked supply. Forests with high PM10 absorption capacity had a great effect, but urban green spaces can be considered a key element in reducing PM10 in daily life. Considering the mismatch of supply and demand, spatial distribution, and population distribution, it is possible to prioritize the supply of urban green spaces to reduce PM10 and, furthermore, support decision making for priority zones subject to forest conservation and designation and cancellation of green spaces, which gives significance to this study.

The Water Deer on a Road: Road-Kill Characteristics of a Nationally Abundant but Internationally Threatened Species

  • Kim, Kyungmin;Seo, Hyunjin;Woo, Donggul;Park, Taejin;Song, Euigeun
    • Journal of Forest and Environmental Science
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    • 제37권1호
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    • pp.62-68
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    • 2021
  • Despite numerous efforts on reducing road-kill worldwide, the collisions have been occurring continuously. Many factors are affecting road-kill occurrences and the effect is various by species. We investigated Hydropotes inermis argyropus road-kill characteristics on the national highway. We examined 9,099 H. i. argyropus road-kill points with distance to the gaps on road (interchange and intersection) and distance to six natural land-cover types as explanatory variables. We also examined the number of road-kill occurrences according to temporal variation using chi-square test with 9,658 events. In general, H. i. argyropus road-kill location tended to occur close to the gaps on road, agricultural lands and forests. The average distance from road-kill to the gap was 694.7 m and 78.6% of the collisions were occurred within 1 km from the gaps. In addition, Kruskal-Wallis test showed the distance between road-kill points and each land cover and the gaps was significantly different. The temporal analyses showed that the differences of the H. i. argyropus road-kill frequency are significant in both month and season. Our results implies H. i. argyropus road-kill location tended to occur close to the gaps on road, agricultural lands and forests in general, especially during May and June, according to their seasonal behavior. Thus, we suggest there is a need of concentrated management on the roads with specific characteristics for both wildlife and human safety.

평창 두타산 산림식생의 군집유형과 입지환경요인의 상관관계 (Relationships between Community Unit and Environment Factor in Forest Vegetation of Mt. Dutasan, Pyeongchang-gun)

  • 이정은;신재권;김동갑;윤충원
    • 한국산림과학회지
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    • 제106권3호
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    • pp.275-287
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    • 2017
  • 본 연구는 두타산 일대 산림식생구조를 밝히고, 식생유형분류와 입지환경인자와의 상관관계 파악을 목적으로 수행되었다. 2016년 6월부터 10월까지 Z-M학파의 식물사회학적인 방법에 의해 식생조사를 수행하여 총 46개소의 식생자료를 획득하였고, 이 자료를 토대로 식생분류를 실시하였다. 그 결과, 최상위 수준에서 신갈나무군락군으로 분류되었으며, 신갈나무군락군은 철쭉군락과 거제수나무군락의 2개 군락으로 분류되었다. 철쭉군락은 동자꽃군과 철쭉전형군 2개의 군으로 세분되었고 동자꽃군은 박새소군과 동자꽃전형소군 2개의 소군으로 세분되었다. 거제수나무군락은 들메나무군과 박달나무군 2개 군으로 세분되었다. 들메나무군은 병꽃나무소군과 승마소군 2개 소군으로 세분되었다. 두타산 일대 산림식생은 총 6개의 식생단위, 14개의 종군단위, 2쌍의 대별종군으로 분류되었다. 수관층위구조의 분석결과, 식생단위별로 임관의 계층이 서로 겹치지 않는 단조로운 구조인 박새소군(식생단위 1), 동자꽃전형소군(식생단위 2), 병꽃나무소군(식생단위 4)과 겹치는 복잡한 구조인 철쭉전형군(식생단위 3) 승마소군(식생단위 5), 박달나무군(식생단위 6)이 나타났다. 승마소군(식생단위 5)의 수직적 계층구조가 가장 발달하였으며, 박달나무군(식생단위 6)은 초본층 식피율이 가장 낮았다. 일치법에 의한 식생단위와 환경요인과의 상관관계를 보면, 해발 1,100 m, 사면 중부, 경사 $20^{\circ}$, 암석노출도 20%, 교목층 DBH 30 cm를 기준으로 철쭉군락(식생단위 1~3)과 거제수나무군락(식생단위 4~6)이 분류되었다. CCA 분석 결과 철쭉군락(식생단위 1~3)은 해발, 지형과 정의 상관관계, 거제수나무군락(식생단위 4~6)은 부의 상관관계 분포경향이 나타났다.

갑천의 조류상 (Avifauna of Gap Stream in Daejeon Metropolitan City)

  • 이준우;이도한;백인환
    • 농업과학연구
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    • 제29권2호
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    • pp.10-19
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    • 2002
  • 본 연구는 갑천의 조류상에 관하여 2001년 9월부터 2002년 8월가지 1년간 매월 조사한 것으로 그 결과는 다음과 같다. 1. 조사된 조류는 12목 31과 83종으로 15900개체 이었고, 물새는 백로과, 오리과, 뜸부기과, 도요 물떼새과 등으로 38종이었으며, 산새는 딱다구리과, 할미새과, 지빠귀과, 휘파람새과, 박새과, 멧새과, 까마귀과 등 45종이었다. 2. 조류의 이동성에 따라 분석하면 텃새 29종(35%), 여름철새 29종(35%), 겨울철새 18종(22%), 그리고 나그네새 7종(8%)이었다. 3. 천연기념물인 새매, 황조롱이, 붉은배새매가 관찰되었다. 4. 주요 우점종은 쇠오리, 흰뺨검둥오리, 청둥오리, 왜가리, 까치, 쇠백로 등의 순으로 이 지역은 수면성오리류와 백로류의 서식에 적합한 서식지환경을 가지고 있는 것으로 판단된다. 5. 종수의 월별 변화는 2월(37종)과 12월(36종)에 높게 나타났으며 6월(27종)과 5월(28종)에 낮게 나타났다. 6. 개체수의 월별 변화는 12월과 1월에 높게 나타났으며 5월과 6월에 가장 낮게 나타났다. 7. 월별 종다양도지수(H')는 9월에 2.6207로 가장 높게 나타났으며 다음으로 6월과 8월에 각각 2.5466, 2.5078의 순으로 높게 나타났고 1월에 2.0716으로 가장 낮게 나타났다.

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에너지 소모량에 기초한 탐방로 난이도 표준화 연구 (Standardization of Trail Difficulty based on Energy Consumption)

  • 홍석환;권태호;최송현;김경태;김동필
    • 한국환경생태학회지
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    • 제29권4호
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    • pp.626-635
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    • 2015
  • 최근 숲길 이용자들이 폭발적으로 증가하고 있으며, 이에 따라 각종 안전장치를 위한 비용 또한 급격히 증가하고 있다. 그럼에도 다른 사고와 달리 심장관련 사고는 줄지 않고 있어 숲길에 제공되는 난이도 정보의 개선방안에 대한 연구를 지리산 둘레길을 대상으로 진행하였다. 기존 숲길에 대한 난이도 정보는 숲을 관리하는 특정인에 의한 경험적 난이도 또는 단순히 거리를 바탕으로 한 난이도를 3~5단계로 구분하여 제공하고 있어 탐방객이 실제 느끼는 난이도와는 괴리감이 있었다. 본 연구에서는 실질적인 에너지소모량을 바탕으로 한 난이도 제공 가능성을 분석하였다. 거리와 경사에 따른 산소소모량의 계산은 숲길 각 구간에 대한 절대적 비교뿐만 아니라 상대적 비교가 가능하였으며 특정 구간의 운동강도를 간단히 표현하는데 효과적이었다. 아울러 시 종점의 변화에 따른 운동량 변화를 쉽게 확인할 수 있었다. 구간별, 산행방향별 운동량에 대한 표준화된 사전 정보제공은 심장관련 사고의 사전예방 효과가 있을 것으로 판단된다.

연소화염 존재 시 수직형 모델 전력선의 섬락 특성 (Flashover Characteristics of Vertical-type Model Power Line in the Presence of Combustion Flame)

  • 김인식
    • 조명전기설비학회논문지
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    • 제23권5호
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    • pp.58-65
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    • 2009
  • 전력선이 통과하는 지역에서 발생된 산불은 계통 섬락사고의 원인이 되고 있다. 본 연구에서는 연소화염에 의한 전력선의 절연내력 저하특성을 알아보기 위해 직류 및 교류 전압 인가 시, 연소화염과 고전압 도체의 수평거리(s)를 변화시켰을 때, 수직형 모델 전력선에 대한 섬락특성을 조사하였다. 실험 결과, 수평거리(s)가 작은 범위에서는 화염이 모델선로의 섬락전압을 크게 감소시킬 수 있는 것으로 나타났다. 이러한 섬락전압의 저하요인을 해석하기 위해 화염주변의 상대공기밀도가 고려되었으며, 화염이 존재하는 경우에는 그 영향이 매우 크게 나타남을 알 수 있었다.

표고 톱밥 재배에서 저온 및 변온 처리가 표고 품질에 미치는 영향 (Effects of Low and Alternated Temperature Treatments on Quality of Oak Mushroom in Sawdust Culture)

  • Park, Kyoung-Sub;Son, Jung-Eek;Yoon, Gap-Hee
    • 한국생물환경조절학회:학술대회논문집
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    • 한국생물환경조절학회 2001년도 봄 학술발표논문집
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    • pp.43-44
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    • 2001
  • Recently the sawdust culture of Lentinus edodes(Berk.) has been gradually extended replacing the log cultivation in Korea. It is indeed able to reduce the use of log and cultivation period in controlled facilities, but is not yet able to produce the high-quality mushroom. The objectives of this study were to examine the effects of low and alternated temperature treatments during the fruiting period on the quality of oak mushroom. At low temperature treatments of 1$^{\circ}C$ and 10$^{\circ}C$, the crack, lightness, hardness, and other characteristics for the high-quality oak mushroom were not improved. However, the crack, brightness, and hardness of cap were increased at alternated temperatures of 5-10$^{\circ}C$ than the other temperature treatments. In conclusion, the alternated temperature treatments were more effective than the low temperature treatment for improving the indices of high-quality oak mushroom such as the crack, brightness and hardness of cap.

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Gastroprotective effect of cirsilineol against hydrochloric acid/ethanol-induced gastric ulcer in rats

  • Gong, Guojin;Zhao, Rigetu;Zhu, Yuhui;Yu, Jinfeng;Wei, Bin;Xu, Yan;Cui, Zhaoxun;Liang, Guoying
    • The Korean Journal of Physiology and Pharmacology
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    • 제25권5호
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    • pp.403-411
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    • 2021
  • This study was designed to evaluate the gastroprotective activity of cirsilineol in hydrochloric acid (HCl)/ethanol-induced gastric ulcer model. Cirsilineol was administered at the doses of 20 and 40 mg/kg in HCl/ethanol-induced rats. The gastroprotective ability was verified by determining the ulcer score, total acidity, hemoglobin, inflammatory cytokines, lipid peroxides, and enzymatic antioxidants superoxide dismutase (SOD) and catalase (CAT) in gastric tissue and serum biochemical analysis. The results showed a favorable increase in the hemoglobin level, antioxidant enzymes (SOD and CAT), restored electrochemical balance (carbon dioxide & anion gap) while a noticeable decrease in ulcer index, total acidity, lipid peroxides, inflammatory cytokines (interleukin-1 beta [IL-1β], IL-6, and tumor necrosis factor alpha) in rats treated with the cirsilineol. The serum biochemical analysis on liver markers (alkaline phosphatases, alanine aminotransferase, and aspartate aminotransferase), kidney markers (urea, creatinine, albumin, globulin, total protein), and lipid profile (triglyceride, high-density lipoprotein, total cholesterol) were attenuated by cirsilineol treatment in rats. Histopathology showed enhanced gastric protection and preserved the integrity of gastric mucosa upon cirsilineol administration. These results ultimately suggest that cirsilineol has gastroprotective effects that prevent the development of gastric ulcer.

Lichen as Bioindicators: Assessing their Response to Heavy Metal Pollution in Their Native Ecosystem

  • Jiho Yang;Soon-Ok Oh;Jae-Seoun Hur
    • Mycobiology
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    • 제51권5호
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    • pp.343-353
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    • 2023
  • Lichens play crucial roles in the ecosystems, contributing to soil formation and nutrient cycling, and being used in biomonitoring efforts to assess the sustainability of ecosystems including air quality. Previous studies on heavy metal accumulation in lichens have mostly relied on manipulated environments, such as transplanted lichens, leaving us with a dearth of research on how lichens physiologically respond to heavy metal exposure in their natural habitats. To fill this knowledge gap, we investigated lichens from two of South Korea's geographically distant regions, Gangwon Province and Jeju Island, and examined whether difference in ambient heavy metal concentrations could be detected through physiological variables, including chlorophyll damage, lipid oxidation, and protein content. The physiological variables of lichens in response to heavy metals differed according to the collection area: Arsenic exerted a significant impact on chlorophyll degradation and protein content. The degree of fatty acid oxidation in lichens was associated with increased Cu concentrations. Our research highlights the value of lichens as a bioindicator, as we found that even small variations in ambient heavy metal concentrations can be detected in natural lichens. Furthermore, our study sheds light on which physiology variables that can be used as indicators of specific heavy metals, underscoring the potential of lichens for future ecology studies.