• 한국음향학회지
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• 제20권7호
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• pp.83-88
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• 2001

본 논문에서는 해양환경 인자의 오정합에 강인한 특성치 추출 기법에 의한 정합장 처리 방법 (FEM: Feature Extraction Method)을 요약하였다. FEM 기법을 이용하여 음원 위치를 추정하는데 선행되어 해결해야 할 두 가지 요소 즉, 제거해야 할 고유벡터의 수와 사용해야 할 환경 샘플 개수에 대하여 고찰해 보고 이에 대한 해결책을 제시하였다. 이 문제점들을 해결하기 위하여 주어진 해양환경에서 진행하는 모드들 중에서 지배적인 모드의 개수와 제거해야 할 고유벡터의 개수와의 관계를 살펴보았다. 그리고 신호벡터가 이루는 공간과 추출해야 할 고유벡터가 이루는 공간을 비교하고 두 공간의 유사성을 정량화하여 분석하였다. 정합장 처리 방법으로 추정한 음원의 위치와 실제 음원의 위치와의 상대적인 오차를 정의하고 분석결과를 보증하였다. 지배적인 모드의 개수만큼 가장 큰 고유벡터를 추출했을 경우 FEM 프로세서가 음원의 위치를 성공적으로 추정하였고, GBNLMIS 해양 환경에서 최소 30개 이상의 환경 샘플을 사용해야 FEM 프로세서의 안정된 성능을 보장할 수 있음을 확인하였다.

• 한국환경생태학회지
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• 제38권3호
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• pp.338-350
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• 2024

강원도 가리왕산, 발왕산, 방태산, 함백산의 아고산대에서 출현하는 사스래나무군락 25개 조사구를 대상으로 식생조사를 실시하고 분석하였다. TWINSPAN 및 DCA 분석 결과, 사스래나무-신갈나무군락(Group I), 사스래나무-당단풍나무군락(Group II), 사스래나무군락(Group III)의 총 3개 군락으로 분류되었다. 사스래나무-신갈나무군락(Group I)은 해발 1,082~1,192m 방태산 등산로 주변에 위치하고, 사스래나무-당단풍나무군락(Group II)은 해발 1,230~1,373m 방태산, 가리왕산, 함백산의 능선과 사면에 위치한다. 사스래나무-신갈나무군락과 사스래나무-당단풍나무군락은 현재 교목층에 사스래나무가 우점하고 있으나 장기적으로는 경쟁 관계인 신갈나무가 우점할 것으로 예상된다. 사스래나무군락(Group III)은 해발 1,428~1,464m 함백산과 발왕산 정상부 전석지에 위치한다. 현재 사스래나무 세력이 매우 우세하고 차세대 형성도 활발하여 앞으로도 사스래나무가 우점할 것으로 예상된다. 사스래나무군락은 일반적으로 해발 1,000m 이상에서 출현하며, 해발고도가 높을수록 사스래나무의 세력이 우세한 것으로 나타났다. 토양 분석 결과, 설악산 대청봉 및 지리산 반야봉 아고산대 지역과 비슷한 양상을 보였다. 군락별 종다양도는 1.210~1.293, 균재도는 0.698~0.795, 우점도는 0.208~0.302로 나타났다.

• Journal of Forest and Environmental Science
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• 제24권3호
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• pp.155-158
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• 2008

Site index is the essential tool for forest management to estimate the productivity of forest land Generally, site index equation is developed and used by relationship between stand age and dominant tree heights. However, there is a limit to use the site index equation in the application of variable ages, environmental influence, and estimation of site index for unstocked land. Therefore, it was attempted to develop a new site index equations based on various environmental factors including site and topographical variables. This study was conducted to develop regional site index equations based on the relationship between site index and soil factors for Pinus densiflora. Environmental factors that obtained from GIS application, were selected by stepwise-regression. Site index Equation was estimated by multiple regression from selected factors. Four environmental factors were selected in the final site index equations by stepwise regression. It was observed that coefficients of determination for site index equations were ranged from 0.34 which seem to be relatively low but good enough for estimation of forest stand productivity. The site index equations developed in this study were also verified to be useful by three evaluation statistics such as model's estimation bias, model's precision and mean square error type of measure.

• 한국농림기상학회지
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• 제8권2호
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• pp.97-106
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• 2006

Site index is an essential tool to estimate forest productivity. Generally, a site index equation is developed and used from the relationship between stand age and dominant tree heights. However, there is a limit to the use of the site index equation in the application of variable ages, environmental influence, and estimation of site index for the unstocked forest. Therefore, it has been attempted to develop a new site index equation based on various environmental factors including site, climate, and topographical variables. This study was conducted to develop a site index equation based on the relationship between site index and environmental factors for the species of Pinus koraiensis in Yangpyung-Gun, Gyunggi Province. The influence of climatic factors (temperature and solar irradiation ratio), topographical factors (elevation, slope, ratio of slope to valley and aspect) and soil profiles (soil depth by layer and soil consistency) on site index were evaluated by multiple regression analysis. Five environmental factors were selected in the final site index equation for Pinus koraiensis. The site index equation developed in this study was also verified by three evaluation statistics: model's estimation bias, model's precision, and mean square error of measurement. Based on the site index equation, the number of productive areas for Pinus koraiensis were estimated by applying GIS technique to digitized forest maps. In addition, the distribution of productive areas was compared with the areas of current distribution of Pinus koraiensis. It is expected that the results obtained in this study could provide valuable information about the amount and distribution of productive areas for Pinus koraiensis reforestation.

• The Journal of Korean Physical Therapy
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• 제32권3호
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• pp.163-167
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• 2020

Purpose: Unilateral strength training effects on contralateral sides have been demonstrated in previous studies for lower extremity exercise, upper extremity exercise, and unilateral surface electrical stimulation. This study was performed to investigate the effects of unilateral ankle training on muscle strength and the balance of contralateral lower extremity in healthy adults. Methods: Thirty healthy subjects were randomized equally to a training or a control group. Those in the training group received unilateral ankle isokinetic strengthening training of the dominant leg (right side) for 4 weeks. Contralateral single-limb balance, including Anterio-Posterior Stability Index (APSI), Medio-Lateral Stability Index (MLSI) and Overall Stability Index (OSI), was assessed before and after intervention. Results: Comparison of pre- and post-test data revealed significant improvements in ipsi- and contralateral ankle strengths, and significant improvement in contralateral single limb balance. Conclusion: These results have practical implications because they demonstrate that unilateral ankle isokinetic exercise improves ankle muscle strength and balance ability of contralateral lower extremity.

• 자원ㆍ환경경제연구
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• 제10권4호
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• pp.569-589
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• 2001

We examine historical contributions of inter fuel substitution, changes in carbon efficiency and energy intensity, growth of economy and population to Korea's $CO_2$ emissions from 1970 to 1998 using the log mean weight Divisia index method. The study reveals that economic growth is the most significant factor to $CO_2$ emissions growth among the five factors. Changes in the fuel substitution and carbon coefficient are found negative contributors to $CO_2$ emissions growth. Energy intensity, which played dominant role in halting $CO_2$ emissions growth in the 1980s, began to play reversed role in the 1990s. When evaluated with the log mean Divisia index technique, deterioration of energy intensity in the 1990s is found worse and expected to contribute $CO_2$ emissions growth further.

• 한국어류학회지
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• 제19권3호
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• pp.210-224
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• 2007

조사기간 동안 남해안 4개 해역에서 자망에 의한 어류의 총 어획량은 577,422.9 g, 어획종수는 총 68종이었다. 전체 어획 종에서 양태가 차지하는 어획량 비율이 가장 높았으며, 다음으로 숭어, 개서대 그리고 보구치의 순이었다. 상대서식량 지수 면에서는 양태, 보구치, 개서대 그리고 숭어가 전체의 63.1%를 점유하였다. 해역별에서는 경남 통영 도남해역이 어획량과 어획종수에서 53,148.8 g, 18종 그리고 우점종은 문치가자미, 양태, 쥐노래미 등이었고, 전남 여수 계동해역이 123,926.9 g, 44종의 어획량과 어획종수 그리고 우점종은 양태, 갯장어, 문치가자미 등이었으며, 전남 장흥 수문해역에서 228,920.9 g, 28종의 어획량과 어획종수, 우점종은 숭어, 양태, 개서대 그리고 전남 진도 모도해역에서는 어획량과 어획종수가 171,426.3 g, 32종 그리고 우점종은 양태, 보구치, 개서대이었다. 따라서, 본 조사에서 남해안의 어류군집은 어획량과 어획종수 그리고 어획 종들에서 해역 간에 차이를 보였다. 이러한 결과는 남해안 해역별 해양환경 조건과 생산성 그리고 어종별 생태습성의 차이에 의한 것으로 볼 수 있다. 그리고, 남해안 연안의 어류는 수온이 상승하고, 염분값이 낮아지는 봄철이후에 점차 증가하는 경향에 있었다.

• 한국측량학회지
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• 제35권5호
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• pp.357-364
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• 2017

The purpose of the study is to develop and validate landslide susceptibility map of Bhotang village development committee, Nepal using FR (Frequency Ration) and SI (Statistical Index) methods. For the purpose, firstly, a landslide inventory map was constructed based on mainly high resolution satellite images available in Google Earth Pro, and rest fieldwork as verification. Secondly, ten conditioning factors of landslide occurrence, namely: altitude, slope, aspect, mean topographic wetness index, landcover, normalized difference vegetation index, dominant soil, distance to river, distance to lineaments and rainfall, were derived and used for the development of landslide susceptibility map in GIS (Geographic Information System) environment. The landslide inventory of total 116 landslides was divided randomly such that 70% were used for training and remaining 30% for validating result by receiver operating characteristics curve analysis. The area under the curve were found to be greater than 0.7 indicating an acceptable susceptibility maps obtained using FR and SI methods in GIS for hilly region of Nepal.

• 한국토양비료학회지
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• 제42권3호
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• pp.160-166
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• 2009

We estimated site productivity for unstocked land based on the relationship between site index (i.e., average height of dominant trees at fixed age) and soil physico-chemical properties of Pinus densiflora stands. Site index relates to a direct method of determining a tree's response to a specific environment such as forest soil and climate conditions. We selected 78 sites in 22 P. densiflora stands of central temperate forest zone, and sampled soils for physicochemical analyzing. And 13 properties of soils were statistically treated by stepwise regression. In the degree of contribution of the variables to site index, the highly effective variables in A horizon were OM, clay content, sand content, available $P_2O_5$, and Exch. $Ca^{{+}{+}}$ inorder, and in B horizon T.N., O.M., Soil pH, cation exchange capacity(C.E.C.), and sand content in order. In both A and B horizon of the soil for P. densiflora stands, the variables commonly contributed to the site index were sand content and OM. These results may be useful to provide not only important criteria for establishment of Pinus densiflora stand sespecially in unstocked land but also aguidance for reforestation.

• 한국소음진동공학회논문집
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• 제25권9호
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• pp.614-619
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• 2015

The purpose of this study is that developing the index which evaluate sound quality of door latch and improving its sound quality through that results. For that, various operating sound of door latch was used for jury test. Loudness and sharpness related metrics are dominant in sound quality index we developed. This research investigate the main transfer path of its operating sound through sound field visualization and get conclusion that could reduce the impact sound of door latch. Therefore, we could verify sound quality improvement of modified product by using sound quality index.