• 제목/요약/키워드: Common Stand

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A Comparative Study on the Mushroom Populations between Matsutake-Producing and Non-producing Pinus densiflora Stands (송이발생림(松栮發生林)과 미발생림(未發生林)의 버섯분포(分布)에 관(關)한 비교연구(比較硏究))

  • Lee, Kyung Joon;Kim, Yang Sup;Lee, Tae Soo;Kim, Kyo Soo
    • Journal of Korean Society of Forest Science
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    • v.72 no.1
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    • pp.27-31
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    • 1986
  • To compare the fungal distribution of matsutake-producing (Tricholoma matsutake) stand with that of non-producing stand, mushrooms on forest floor were collected in September of 1984 from 28-year-old non-producing and 55-year-old matsutake-producing stands of Pinus densiflora in Kangwon Province. A total of 18 fungal species in 12 genera were collected from a non-producing stand, and all the species except one were putative ectomycorrhizal. Common genera in non-producing stand included Suillus, Russula, Lactarius, Hydnum, and Amanita. From a matsutake-producing stand a total of 30 fungal species in 22 genera were collected, of which 22 species were ectomycorrhizal. Common genera in the producing stand included Hydnum, Tricholoma, Laccaria, and Cantharellus. Common species in both stands were six species only. It is concluded that matsutake-producing stand had more diversified fungal population than non-producing stand, probably because of higher contents of organic matters in soil and better development of understory vegetation through the ageing of the stand.

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Jain's hand retractor system and stand: an innovative device for hand surgery

  • Jain, Aakansh
    • Archives of Plastic Surgery
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    • v.48 no.4
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    • pp.389-391
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    • 2021
  • Solo hand surgery is becoming increasingly common, mostly due to a lack of assistants and dedicated operating theatres. The solo hand surgeon faces challenges of proper hand positioning, elevation, and skin flap/tissue retraction. Most commercially available hand retractors or stands do not address all the relevant problems and are not economically feasible for trainee surgeons. The Jain's hand retractor system and stand, described herein, provides solutions to all these problems, and its simple design helps surgeons to reproduce it easily.

Modeling of Solar/Hydrogen/DEGS Hybrid System for Stand Alone Applications of a Large Store

  • Hong, Won-Pyo
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.11
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    • pp.57-68
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    • 2013
  • The market for distributed power generation based on renewable energy is increasing, particularly for standalone mini-grid applications in developing countries with limited energy resources. Stand-alone power systems (SAPS) are of special interest combined with renewable energy design in areas not connected to the electric grid. Traditionally, such systems have been powered by diesel engine generator sets (DEGS), but also hybrid systems with photovoltaic and/or wind energy conversion systems (WECS) are becoming quite common nowadays. Hybrid energy systems can now be used to generate energy consumed in remote areas and stand-alone microgrids. This paper describes the design, simulation and feasibility study of a hybrid energy system for a stand-alone power system. A simulated model is developed to investigate the design and performance of stand-alone hydrogen renewable energy systems. The analysis presented here is based on transient system simulation program (TRNSYS) with realistic ventilation load of a large store. Design of a hybrid energy system is site specific and depends on the resources available and the load demand.

Investigating the Effect of Planting Density on Parameter Estimation of Stand Growth Models (식재(植栽) 밀도(密度)가 임분생장(林分生長)모델 모수(母數) 추정(推定)에 미치는 효과(效果)에 관(關)한 연구(硏究))

  • Li, Fengri;Kwon, Soonduk;Chung, Joosang
    • Journal of Korean Society of Forest Science
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    • v.88 no.4
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    • pp.446-453
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    • 1999
  • In this study, the effects of stand planting density on parameters of stand height and basal area growth models were investigated. We used the Korf equation as the base model in estimating the parameters of the growth models for cryptomeria plantation forest stands. Then, in order to investigate the effects of the change in plantation density on the parameter estimates, the "extra sums of square" principle, which provided a reasonable statistical procedure for a performance test, was used. The results of the test coincide with the understandings that stand height growth is not affected significantly by the planting density and the growth curves of stand basal area approaches a common asymptote regardless of the stand density for a given site. However, the shapes of the basal area growth curves were affected significantly by the planting density. Based on the results of the test, we developed a basal area growth model to account for the effects of initial planting density in cryptomeria plantation forest stands.

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A Fatigue Analysis of the Common Stand in a Steel Mill through the Evaluation of Thermal Effects (열영향 평가를 통한 제철공장 공동가대의 피로해석)

  • Park, Y.K.;Kim, J.G.
    • Journal of Power System Engineering
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    • v.10 no.4
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    • pp.90-98
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    • 2006
  • 본 연구에서는 체철공장에서 래이들 카의 매우 높은 열에 주기적으로 빈번히 노출되는 공동가대의 열적 피해에 대한 체계적인 평가를 수행하였다 먼저 실험과 함께 유한요소법을 사용한 열해석이 수행되었다. 기존 공동가대와 향후 설치될 신 공동가대 모두에 대한 적합한 기준을 검증하기위하여 가장 심각한 상태에 대한 열평가가 포함되었다. 또한 공동가대에 적합한 방열판의 설계를 위하여 실험결과에 근거한 수치해석이 사용되었다. 마지막으로 새로 설치될 공동가대의 안전성과 내구성을 평가하기위한 피로해석을 수행하였다. 6m 신형공동가대의 열응력해석 및 피로해석 결과 기존 공동가대보다는 취약하나 설치 및 사용에는 문제가 없음을 확인하였다.

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Treatment and Rehabilitation in a Common Kestrel (Falco tinnunculus) with Both Legs Broken (양쪽 다리 골절 황조롱이의 치료와 재활 1례)

  • Kim, Hee-jong;Kim, Young-jun;Kim, Moon-jung;Park, Young-seok;Kim, Byeong-su;Park, Seong-jun
    • Journal of Veterinary Clinics
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    • v.36 no.1
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    • pp.82-84
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    • 2019
  • A common kestrel (Falco tinnunculus) was presented with inability to stand and fly at Chungnam Wild Animal Rescue Center. The kestrel showed non-weight bearing ambulation on both legs and crepitation with no external wound. Radiographs revealed a fracture on mid-diaphysis of right tibiotarsus and a distal end fracture of left femur. Intramedullary pinning was chosen for reduction of both fractures. The right tibiotarsal fracture was corrected first, and left femur was repaired 5 days later. The kestrel was managed with a specially designed sling to prevent further iatrogenic damage for 2 weeks. Three weeks after the surgery, the kestrel was able to stand and found to perch in 4 weeks. On 5 weeks, The kestrel could fly free at outdoor aviary and was released through rehabilitation for 3 months finally.

Development of Stand-Alone Underground Water Pumping System using Photovoltaics System (태양광발전을 이용한 독립형 지하수 양수 시스템 개발)

  • Lee, Seung-Hun;Hwang, Jung-Hoon;Cho, Woon-Sik;Kim, Man-Il;Lee, Joon-Gee;Park, Moon-Hee
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.69-72
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    • 2009
  • In this paper, the Stand-alone underground water pumping system was developed that is consist of Submersible Pump (AC type), Photovoltaic Array and Power converter by the application of solar energy. And also wish to introduce system that is possible to supply of drinking water or water for agriculture using solar energy at desertification area or a Off-grid area, interior etc. and operation test results. This system can use in deep tube well of 200m range with common Submersible Pump and maximized to the quantity of pumping through M.P.P.T control. Also system availability raised through apply various driving mode.

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Effects of shot peening stand-off distance on electrochemical properties for surface modification of ALBC3 alloy (ALBC3 합금의 표면 개질을 위한 쇼트피닝 분사거리가 전기화학적 특성에 미치는 영향)

  • Han, Min-Su;Hyun, Koang-Yong;Kim, Seong-Jong
    • Corrosion Science and Technology
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    • v.12 no.5
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    • pp.233-238
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    • 2013
  • In the case of casting materials or ductile materials for marine equipment, it is common to employ a surface modification for achieving cost reduction and improvement in strength. In particular, aluminium bronze ALBC3 exhibits excellent corrosion resistance, and thus widely used for marine application. However, application of the material under high-velocity seawater flow may induce electrochemical corrosion damage and physical damage such as cavitation erosion, leading to shorter service life of equipment. In this study, surface modification was carried out on ALBC3 alloy for different shot peening stand-off distances, and the physical hardness and electrochemical characteristics before and after modification were investigated. The results in each case showed the hardness increase in comparison with non-peened specimen, and the maximum hardness improvement(50 %) was found in 10 cm of shot-peening stand-off distance. It is observed that the electrochemical characteristics were irrelevant to application of shot peening.

Some Peculiarities of Structure and Growth of Larch Stands in Western Mongolia

  • Tsogtbaatar, J.;Battulga, P.
    • The Korean Journal of Quaternary Research
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    • v.18 no.2 s.23
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    • pp.107-107
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    • 2004
  • In this paper we have introduced some results of study on stand growth pattern and stand structure of larch forest which are located in selected forest sites of Khangai and Gobi-Altai mountain ranges of Mongolia. Our investigations showed that growth intensity and stand structure in western Mongolia are very specific from the other forest vegetation zones of Mongolia. Studies on the stand structure and growth trend indicate that tree types of stand structure and different types of growth of Larix sibrica are very common in Western Mongolia. These peculiarities of stand structure and growth of larch stands in Western Monolia could be used for inventory work and an improvement of the forest management in Western Mongolian region. The larch tree is the dominant tree species in Western Mogolia. Forest cover of the region is about 15%, which is two times higher than the country's average. In this region forest area is divided into 4 forest sub-regions: the Central Khangai, Western Khangai, North Eastern Khangai and South Easterun Khangai sub-regions including taiga, pseudo taiga, sub taiga, sub-alpine and forest steppe belts. Silviculture practices and forest research management request to study forest growth trends in local and general conditions, which means to indicate a change of taxonomic characteristics of stand from time to time including diameter, height, basal area, growth stock etc. The forest management practice mostly uses tables of forest growth and yield based on the results of long term research on forest growth. Forest yield tables and other relevant forest standards of Russia are used for the forest inventory and forest management. They are not able to determine forest structure and growth peculiatities of Mongolian forests. Studies on forest resource assessment in Mongolia indicate that after logging operations and forest fires the natural regeneration of desired species such as pine and larch often does not succeed. This situation forces to take a different approach of forest management and silviculture practice depending on the stand structure and growth rate of the forest stands. According to our investigation in last years, forest growth pattern of larch forest depends mostly on stand structure, stand age and growth condition including forest soil, climate and location in different slopes. Due to improve environmental function of forest ecosystem in the region, it is needed to conduct very comprehensive study of high mountain forest ecosystem in selected sub-regions.

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Design of a control scheme for applying DC power sources to a distribution system (배전시스템에 DC 전력원을 적용하기 위한 제어 기법 설계)

  • Hwang, Chul-Sang;Kim, Gyeong-Hun;Byeon, Gilsung;Jeon, Jin-Hong;Jo, Chang-Hee;Park, Minwon;Yu, In-Keun
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.1056-1057
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    • 2015
  • A common DC bus is a useful connection for several DC output sources such as photovoltaic (PV), fuel cells, and batteries. Operation of the common DC power system with more than two DC output sources, especially in a stand-alone mode, requires a control scheme for the stable operation of the system. In this paper, a control scheme has been developed for applying DC power sources to the distribution system. The purpose of the control scheme is to make the best use of the DC power sources. The DC power system consists of PV, two energy storage systems and a DC-AC inverter with the control scheme. A distribution system was modeled in PSCAD/EMTDC. As the results, the control scheme is applied to the DC-AC inverter and the DC-DC converter for transfer operations between the grid-connected and the stand-alone mode to keep the DC bus and the AC voltage constant. The results from the simulation demonstrate the stable operation of a grid connected DC power system.

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