• Title/Summary/Keyword: stand.

Search Result 3,489, Processing Time 0.033 seconds

The Effect of Birds in the Families Ardeidae and Corvidae on Stand Structure in Bamboo Groves

  • Seo, Myoung-Won;Woo, Hyo-Jin;Lee, Gil-Seong;Choo, Yeon-Sik;Lee, Ki-Sup;Choi, Kee-Ryong;Park, Yong-Mok
    • Journal of Ecology and Environment
    • /
    • v.31 no.4
    • /
    • pp.333-339
    • /
    • 2008
  • We investigated death rates, growth rates and recruitment of culms in two neighboring bamboo (Phyllostachys bamboosoides) stands nested in by two different bird species to analyze stand structure and to design conservation strategies. A third bamboo grove not used by birds, the Taewha stand, was included as a control stand. The bamboo stand occupied by birds in the family Ardeidae (the Ardeidae stand) had an approximately 1.5 times higher culm density than the stand occupied by birds in the family Corvidae (the Corvidae stand). The crude death rate and the number of newly emerged shoots were also higher in the Ardeidae stand than the Corvidae stand. The death rate for bamboo in the Ardeidae stand was not dependent on diameter at breast height (DBH) and was almost 40% for culms of all sizes, whereas most dead culms in the Corvidae stand were < 4 cm DBH. Consequently, we conclude that in the Ardeidae stand, density-independent causes of death are operating, while density-dependent factor are more important in the Corvidae site. The results of soil analysis in these stands suggest that the density-independent death pattern observed in the Ardeidae stand may be due to soil acidification resulting from wastes produced by the birds during breeding. On the other hand, the culm distribution and death patterns in the Corvidae stand suggest that the stand characteristics were not affected by the nesting birds. These results suggest that different conservation strategies must be applied to conserve bamboo groves used by ardeids and corvids for nesting.

Vegetation Structure and Soil Characteristics around Camellia japonica Stand in Hakdong, Geoje Island (거제 학동 동백나무림 주변의 식생구조 및 토양특성)

  • Chung, Jae-Min;Jung, Hye-Ran;Kang, Jin-Taek;Moon, Hyun-Shik
    • Journal of agriculture & life science
    • /
    • v.44 no.3
    • /
    • pp.31-40
    • /
    • 2010
  • This study was carried out to offer a basis data for conservation and application of effective management of Camellia japonica stand in Hakdong, Geoje Island. Field survey was conducted at C. japonica stand, mixed stand, Chamaecyparis obtusa plantation, and Pinus thunbergii stand. Importance value of C. japonica at tree layer was highest in C. japonica stand and mixed stand, and that of C. obtusa and P. thunbergii were highest in C. obtusa plantation and P. thunbergii stand, respectively. At subtree layer, C. japonica, Callicarpa dichotoma, Neolitses serices, and Styrax japonica had the highest importance value in C. japonica stand, mixed stand, C. obtusa plantation, and P. thunbergii stand, respectively. The species diversity ranged from 0.121 to 1.589 in C. japonica stand, 0.543 to 1.540 in mixed stand, 0.276 to 1.321 in C. obtusa plantation, and 0.764 to 1.523 in P. thunbergii stand, respectively. Soil pH was 5.72 in C. japonica stand, 5.26 in mixed stand, 5.21 in C. obtusa plantation, and 5.32 in P. thunbergii stand. The content of organic matter and total N were 5.77, 0.48% in C. japonica stand, 4.41, 0.30% in mixed stand, 3.28, 0.33% in C. obtusa plantation, and 5.32, 0.28% in P. thunbergii stand.

Development of a Stand Density Management Diagram for Teak Forests in Southern India

  • Tewari, Vindhya Prasad;Alvarez-Gonz, Juan Gabriel
    • Journal of Forest and Environmental Science
    • /
    • v.30 no.3
    • /
    • pp.259-266
    • /
    • 2014
  • Stand Density Diagrams (SDD) are average stand-level models which graphically illustrate the relationship between yield, density and mortality throughout the various stages of forest development. These are useful tools for designing, displaying and evaluating alternative density regimes in even-aged forest ecosystems to achieve a desired future condition. This contribution presents an example of a SDD that has been constructed for teak forests of Karnataka in southern India. The relationship between stand density, dominant height, quadratic mean diameter, relative spacing and stand volume is represented in one graph. The relative spacing index was used to characterize the population density. Two equations were fitted simultaneously to the data collected from 27 sample plots measured annually for three years: one relates quadratic mean diameter with stand density and dominant height while the other relates total stand volume with quadratic mean diameter, stand density and dominant height.

The Effects of Self-Sit-to-Stand Training Using Multi-Sensory Feedback Device on Balance Ability and Sit-to-Stand Ability in Hemiplegic Stroke Patients (다중감각 되먹임 장치를 이용한 자가 일어서기 훈련이 편마비 환자의 균형능력과 일어서기 동작 수행능력에 미치는 영향)

  • Min, Jun-Ki;Choi, Won-Jae;Jung, Jihye;Lee, Seung-Won
    • PNF and Movement
    • /
    • v.20 no.2
    • /
    • pp.157-166
    • /
    • 2022
  • Purpose: The aim of this research was to investigate the effects of self-sit-to-stand training on balance ability and sit-to-stand ability in hemiplegic stroke patients using a multisensory feedback device. Methods: A total of 19 stroke patients participated in this study, and they were divided into two groups: 10 underwent self-sit-to-stand training using a multisensory feedback device, and 9 underwent sit-to-stand training with a physical therapist. In both groups, sit-to-stand training was performed for 30 min, 3 times a week, for 6 weeks. The subjects also underwent physical therapy twice a day for 30 min, 10 times a week, for a total of 60 sessions. Balance ability was evaluated using the AFA-50 and Berg Balance Scale. Sit-to-stand ability was evaluated using the five times sit-to-stand test. Results: Sway length, pressure, and total pressure all significantly increased in both groups, and there was no difference between the two groups. The Berg Balance Scale results showed that balance ability significantly increased in both groups, and there was no difference between the two groups. The five times sit-to-stand test results showed that sit-to-stand ability significantly increased in both groups, and there was no difference between the two groups. It was found that the self-sit-to-stand training using a multisensory feedback device had a positive effect on balance control and sit-to-stand ability. When the two groups were compared, no difference in balance ability or sit-to-stand ability was observed. Conclusion: The findings of this study indicate that self-sit-to-stand training using a multisensory feedback device is as effective as sit-to-stand training with a physical therapist. Hence, self-sit-to-stand training using a multisensory feedback device could be an effective home-based exercise protocol for hemiplegic stroke patients to improve their balance and sit-to-stand abilities.

Classification of Quercus mongolica Stand Types at Mt. Joongwang, Kangwon-Do and Determination of Proper Future Tree Density for Forest Tending Work (중왕산(中旺山) 지역(地域) 신갈나무림(林)의 임분형(林分形) 구분(區分) 및 육림작업(育林作業)에 적절(適切)한 미래목(未來木) 본수(本數)의 결정(決定))

  • Choi, Seon Deok;Lee, Don Koo;Ma, Sang Kyu
    • Journal of Korean Society of Forest Science
    • /
    • v.87 no.4
    • /
    • pp.631-641
    • /
    • 1998
  • The objectives of this study were 1) to classify the types of Quercus mongolica stands at Mt. Joongwang and compare their quality, and 2) to determine the proper future tree number of Q. mongolica per ha and the appropriate distance between the future trees. The results from this study were as follows : Q. mongolica stands at Mt. Joongwang was classified into four types, pure Q. mongolica stand as stand type I, Q. mongolica - hardwood stand as stand type II, Q. mongolica - Pines densiflora stand as stand type III, Hardwood - Q. mongolica stand as stand type IV, according to mixture rate in stand volume. Stand type IV showed the best quality stem of Q. mongolica among the stand types, and the stem quality of Q. mongolica in Q. mongolica stand mixed with hardwood as stand types II and IV was better than those in pure Q. mongolica stand as stand type I and in Q. mongolica - P. densiflora stand as stand type III. If the management goal for Q. mongolica stand is to produce its high quality-timber, it is desirable to sustain proper mixture rate of Q. mongolica with another hardwoods. The proper number of future trees in pure Q. mongolica stand as stand type I was 122trees/ha and reasonable distance between the future trees was 9.15m. The distance between future trees in other stand types was 7.2m to 9.3m for stand types II and IV, while 8.0m for stand type III. Thus, the classification of Q. mongolica stand type based on stand character and maturity, and proper stem number of future tree and optimum distance between future trees would be a useful forest tending work.

  • PDF

Comparison of Center of Pressure Displacement during Sit to Stand to Sit and Balance Ability of Subjects with and without Chronic Ankle Instability

  • Hyun-Sung Kim;Seung-Jun Oh
    • Journal of The Korean Society of Integrative Medicine
    • /
    • v.11 no.1
    • /
    • pp.13-20
    • /
    • 2023
  • Purpose : The purpose of this study is to compare the balance ability between subjects with chronic ankle instability and normal people and the center of pressure displacement during the sit to stand and stand to sit. Methods : The subjects of this study were 63 who met the inclusion criteria and were classified into normal group (n=33) and chronic ankle instability group (n=30). The displacement of the center of pressure during sit to stand and stand to sit was measured. And the limit of stability and Y-balance tests were performed to measure the balance ability. Independent t-test was conducted to compare center of pressure displacement and balance ability between groups, and pearson correlation was conducted to analyze the correlation between the center of pressure displacement and balance ability. Results : In the case of the center of pressure displacement, there was a significant difference between the two groups during sit to stand and stand to sit. In the case of balance, both limit of stability and Y-balance test showed significant differences between the two groups. At the time of sit to stand, the center of pressure displacement showed a significant correlation with balance abilities, and at the time of stand to sit, the center of pressure displacement showed a significant correlation with Y-balance test. Conclusion : Chronic ankle instability shows that there is a lot of sway in the body due to compensation to replace the decrease in ankle joint range of motion when performing sit to stand and stand to sit due to sensory input damage such as decrease in ankle range of motion and decrease in ankle proprioception. Chronic ankle instability is expected to have a negative effect on our daily lives in life. The results of this study will serve as the basis for the dynamic approach to objective evaluation, treatment, and prevention of chronic ankle instability.

Estimating the Stand Structure Index Based on Lorenz Curve (Lorenz곡선(曲線)에 근거(根據)한 임분구조지수추정(林分構造指數推定))

  • Lee, Woo-Kyun
    • Journal of Korean Society of Forest Science
    • /
    • v.86 no.2
    • /
    • pp.158-166
    • /
    • 1997
  • This study presents the method to quantify the stand structure diversity or homogeneity. Gadow's dbh differentiation(Durchmesserdifferenzierung) is introduced which quantifies the horizontal stand structure by the ratio of the dbh between subject tree and neighbour trees. And new stand structure diversity index based on Lorenz curve, which is made by ratio of tree number and basal area or volume by dbh class, is presented. The horizontal stand structure index based on Lorenz curve has a value from 0 to 1 as Gadow's index, and approximates to 1 if the stand structure has high diversity. In the comparative analysis for performance, the new stand structure index based on Lorenz curve is considered to compare with the Gadow's index for describing the stand structure.

  • PDF

A Basic Survey about Stand Structure of Old Korean Fir(Abies holophylla) Stands in Mt. Sorak (내설악 전(젓)나무 고목림 구조 기초 조사)

  • Chung Eui-Gyung;Youn Young-Il
    • Korean Journal of Environmental Biology
    • /
    • v.23 no.2 s.58
    • /
    • pp.141-145
    • /
    • 2005
  • Forest stand structure was surveyed to understand the Korean fir (Abies holophylla) dominant forest ecosystem in Nae-Sorak mountain. Despite limited surveyed area, a diverse forest structure, a characteristic in natural forests, is well presented in the area. According to Leibundgut's (1984) classification of forest structure, stand A, B represents declining stage, stand C regeneration stage, stand D combination of stabilizing and declining stage, and stand E unstable stage of selection.

Power consumption evaluation of Set-top box mode transition scheme considering passive stand-by mode (수동대기모드를 고려한 셋톱박스 모드전환 기술의 에너지 절감 성능 분석)

  • Kim, Yong-Ho;Kim, Hoon
    • Journal of The Institute of Information and Telecommunication Facilities Engineering
    • /
    • v.10 no.4
    • /
    • pp.135-142
    • /
    • 2011
  • This paper proposes a performance evaluation method for power consumption of set-top box (STB) stand-by mode transition schemes. A stand-by mode transition scheme characterizes the timing of mode transition. The timing of mode transition affects the duration of stand-by mode operation, and the power consumptions of STB as well. Recently a fast stand-by mode transition scheme (FMT) has been proposed based on user input for selecting the device to be connected to TV. In this paper, we evaluate power consumption of FMT and a conventional mode transition scheme. For the computation of the duration of stand-by mode operation, the user input events are modeled as Poisson process. Simulation results based on the modeling reveals that the proposed scheme is more effective in power saving than the conventional scheme by up to 30%.

  • PDF

Taxi Stand Approach Sequence Management System to reduce Traffic Jam and Congestion around Taxi Stand (택시 승강장 주변 교통 정체 및 혼잡 감소를 위한 승강장 진입 순번 운용 시스템)

  • Gu, Bongen;Lee, Kwondong;Lee, Sangtae
    • Journal of Platform Technology
    • /
    • v.6 no.1
    • /
    • pp.17-23
    • /
    • 2018
  • Taxi's queue for entering into taxi stand makes traffic jam and congestion around taxi stand. If we make that taxi waits in another place around taxi stand, and can approach to taxi stand when it gets in its turn, these traffic jam and congestion around taxi stand can be reduced. In this paper, we propose entry sequence operating system for taxi stand to reduce traffic jam and congestion around taxi stand. In this system, taxi driver can request his sequence number, and the system issues sequence number to driver. When it is time to approach to taxi stand due to issued sequence number, the proposed system notifies to taxi driver via taxi terminal. Taxi getting the proposed service can wait in another place around taxi stand, and can approach to taxi stand after receiving notify for approaching. Therefore, the proposed system in this paper can reduce traffic jam and congestion around taxi stand because it can reduce or get rid of taxi's queue around taxi stand. We implement the taxi stand approach sequence management system proposed in this paper for taxi stand installed in Chungju-Si, Chungbuk. We use Google Cloud service and Android platform for implementing.