• Journal of Forest and Environmental Science
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• 제33권4호
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• pp.257-269
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• 2017

The study has piloted to find the Pattern of species distribution along environmental variables and disturbance in Raghunandan Reserve Forest. Shaltila and Shahapur beat of Raghunandan Hill Reserve Forest are situated in Chunarughat sub-district of Habiganj district between $24^{\circ}5^{\prime}-24^{\circ}10^{\prime}N$ and $91^{\circ}25^{\prime}-91^{\circ}30^{\prime}E$ under the Sylhet Forest Division. The Environmental variable and vegetation data were collected from 30 sample plots from each forest beat by using arbitrary sampling without preconceived bias. 51 species were found from Shaltila and 34 species found in Shahapur forest beat. Thus the dataset continued with total 85 species in 60 samples. To determine the relationships between tree species distribution and environmental variables, Canonical Correspondence Analysis (CCA) ordination method were performed separately for two forest beat. In CCA ordination, tree species showed significant variation along environmental gradients in terms of soil organic matter and disturbances (p<0.05) in the case of Shaltila forest. Potassium has a significant relationship with axis 1 and axis 2 in this forest. But Shahapur forest showed no significant relationship between species and environmental variables. Phosphorus has a significantly negative relationship with axis 2 in this forest. Disturbance played as a critical role of this forest thus influencing the distribution of species. The study showed that the distributions of tree species are strongly influenced by disturbance and organic matter in Shaltila and Shahapur forest beat showed no significant relationship between species and environmental variables. Future research should be included more environmental variables with larger study area that identify the most important environmental forces which will drive by species distribution findings in this forest.

• 한국조경학회지
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• 제16권1호
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• pp.13-26
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• 1988

^x This study was executed to analyze the vegetational landscape structure of Donggu Royal Tomb forest by four kinds of ordination techniques(polar, principal component analysis, reciprocal averaging, and detrended correspondence analysis) and comparison of the couple photographs between 1920s and 1987. Thirteen sites were sampled with clumped sampling method in June of 1987 and five quadrats were examined in each site. The result of this study can be summarized as follows. 1. Environmental impact grade 3,4 and 5 area covered 16.11ha and these area should be restored by the input of human energy because self - refair seemed to be impossible. 2. Pinus densiflora community of actual vegetation covered 8.2%, Alnus japonica community 5.7% and quercus aliena community 15.8% of the surveyed area(73.3ha). And afforested vegetation including Pinus koraiensis, Pinus rigida, Alnus hirsuta and Robinia pseudoacacia covered 27.0%. 3. Donggu Royal Tomb forest was divided by Pinus densiflora, P. densiflora-Quercus aliena, Alnus japonia - Q. aliena and A. japonica community. DCA was the most effective method of this study. 4. DCA ordination were showed that succesional trends of tree species seem to be from Pinus densiflora through Prunus sargentii, Quercus serrata, Quercus aliena to Carpinus laxiflora in P. densiflora community and from Alnus japonica through Acer ginnala to Q. aliena in A. japonica community of the upper layer and from Rosa multiflora, Symplocos chinensis for. pilosa, Zanthoxylum schiniflolium through Rhus trichocarpa, Styrax japonica, Rhododendron scilippenbachii to Viburum erosum, Lindera obtusiloba in the middle layer. 5. By the comparsion of the couple photographs beween 1920s and 1987, we can recognize the change of historical landscape composed by P. densiflora and A. japonica community and those community is succeed to Q. aliena.

• 한국환경복원기술학회지
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• 제7권2호
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• pp.52-61
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• 2004

This study has been carried out to classify forest vegetation in south and north slopes of Donghaksa valley for supplying basic data for conservation and restoration of the valley. With the phytosociological method, the forest of the south and north slopes of Donghaksa valley was classified as four groups; Quercus variabilis community, Quercus mongolica community, Pinus densiflora community and Carpinus laxiflora community. The dominant species were found in the order of Pinus densiflora, Quercus variabilis, Carpinus laxiflora, and Quercus mongolica. Comparing the north and south slopes, Quercus variabilis were the highest dominant species in the south and Carpinus laxiflora in the north. Pinus densiflora were the next dominant species in both south and north slopes. According to the DBH analysis result, Pinus densiflora and Quercus variabilis had density of normal distribution style among the entire community. Therefore, their dominance are expected to continue for now. But, Quercus mongolica and Carpinus laxiflora are expected to extend their influence in the future in terms of competition with Pinus densiflora. The correlation between each community and the environment according to DCCA ordination was examined in this study. The result told us that Quercus variabilis is distributed mainly on the south slope in a mid-steep and mid-altitude area. Quercus mongolica community appeared on the north slope in the steep high-altitude area that has high percentage in total nitrogen and CEC. Pinus densiflora community is distributed on both south and north slopes in a gentle slope and low-altitude area. Carpinus laxiflora is distributed on the north slope in a mid-steep and mid-altitude area.

• 한국조경학회지
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• 제21권2호
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• pp.50-67
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• 1993

This study analyzed the distribution and structure of the vegetation landscape in Naejangsan National Park. The plant distribution was investigated using a field survey. There were 72 sites sampled using the clumpled sampling method. The data derived from the investigation was analyzed using the quantitative analysis of Bray-Curtis method. The analysis was performed by the classification of TWINSPAN. The ordination of DCA and RA was used for the species composition and successional trends. The results are as follows; 1. Quercus. serrata-Q. variabilis community as 21.76(16.49$\textrm{km}^2$), was the largest community in the actual vegetation of the Naejangsan National Park. The degree of green naturality index 8 area covered 64.8% of the study area and the index 6 area did 16%. 2. Classified by the ordination of DCA and environmental variables, such as the plant community was divided into seven groups according to the altitude and forming groups; Chamaecy Paris. pisifera-P.densiflora community, P.densiflora community, Q.variailis community, T.nuciofera-A.palmatum community. 3. Ther species diversity and evenness indices of C.pisifera-P.densiflora community, P.densiflora community appeared low but C.laxiflora communitywhich was the most stable community in the study area. 4. The similarity indices between Q.variabilis community and Q.serrata-Q.variabilis community were calculated 58.84%, but those between other communities were comparatively low level. 5. The successional trends of DBH class seem to be from C. pisifera-P.densiflora community, P.densiflora community to Quercus species community and from Q.variabilis community, Q.serrata-Q.variabilis community to Carpinus species community. 6. Results suggested that the successional trends in Naejangsan National Park; P.densiflora community\longrightarrowQ.variablilis community, Q.serrata-Q.variabilis community\longrightarrowC.laxiflora community in sequence.

• 한국산림과학회지
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• 제110권4호
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• pp.530-542
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• 2021

백두대간 보호지역 일본잎갈나무림의 생태적 관리를 위한 기본 단위 설정을 위하여 총 119개 조사구에서 수집한 식생 정보를 바탕으로 TWINSPAN과 DCA ordination 분석을 통하여 현존식생의 유형을 분류하고 그 공간 배열 상태를 파악, 기술하였다. 현존식생 유형은 신갈나무-철쭉형, 신갈나무-조록싸리형, 층층나무-산뽕나무형, 신갈나무-까치박달형, 비목나무-찔레꽃형, 졸참나무-산초나무형, 졸참나무-조릿대형 등 총 7개 유형이 도출되었고 대개 위도, 해발고도, 성립 기간, 시업 이력, 주변 임분 특성, 교란 정도 등에 따른 종조성적 차이를 반영하고 있었다. 또한 일본잎갈나무림과 주변 잠재자연식생(신갈나무림와 졸참나무림)의 종구성적 유사성을 Jaccard 계수에 의해 비교한 결과, 식생유형 간 다소 차이가 있지만 신갈나무림과는 평균 0.21, 졸참나무림과는 평균 0.32로 나타나 아직 전반적으로 종구성이 이질적인 경향이었다.

• 한국환경복원기술학회지
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• 제21권6호
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• pp.71-82
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• 2018

This study was conducted to provide ecological basic data that use to establish environmental conditions for cultivation of wild vegetables in 2016-2018. Therefore, we investigated the vegetation structure and the correlation between the community structure and the environmental factors for natural habitats of wild vegetables(Aster glehni, Allium ochotense, and Aruncus sylvester) distributed in Ulleungdo. As a result of population and gradient analysis, the vegetation was classified into Aster glehni community, Allium ochotense community, and Aruncus sylvester community. We confirmed that the classification by population analysis was consistent with that by TWINSPAN method, suggesting that they were complemented each other. The importance value of Aster glehni was the highest in all communities, followed by Aruncus sylvester, Allium ochotense, Hydrangea petiolaris, Dryopteris crassirhizoma, Asperula ldorata, Phryma leptostachya var. asiatica, Disporum viridrescens, Hedera rhombea, Anthriscus sylvestris, and Hepatica maxima. According to the results of DCCA ordination analysis, among those communities, the Aster glehni community was distributed in soil where the nutrition including T-N and O.M. were intermediate. The Allium ochotense community was distributed on the a little high northern slope at the highest altitude where the CEC and O.M. were the highest, and other nutrition and pH were low. The Aruncus sylvester was distributed on high slope and altitude on which the amount of exchangeable cation such as $Ca^{{+}{+}}$, $Mg^{{+}{+}}$ and pH were high, and the CEC, $P_2O_5$, and O.M. were the lowest.

• 환경영향평가
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• 제31권6호
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• pp.388-408
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• 2022

이번 연구는 멸종위기에 처한 아고산 침엽수인 가문비나무의 지형특성에 따른 지표종을 선정하고, 생물다양성 평가에 필요한 과학적 근거자료를 마련하고자 진행되었다. 남한과 중국 내 가문비나무림은 남방한계선으로 지리적 가치가 높은 지역이다. 위도는 식물생태계의 지리적 가치에 큰 영향을 미치며, 위도와 서식지의 차이는 산림의 종구성 변화에 영향을 미친다. 지리적 차이뿐 아니라 환경변화로 아고산 식물서식지는 점차 쇠퇴하여 결국 멸종위기에 처한다. 이러한 측면에서, 지리적 가치가 높은 한국과 중국의 가문비나무림에 대한 개체군 모니터링으로 지표종을 선정할 필요가 있으며, 지표종에 대한 다양한 분석을 통해 생물다양성 평가의 기초자료를 구축할 필요가 있다. 개체군 모니터링은 한국과 중국의 가문비나무림에 87개의 원형조사구(400m²)를 설치하여 수행하였고, MRPP-test, NMS ordination 등의 과정을 통해 이에 근거하여 지표종을 선정 한 후 생물다양성 평가의 기초자료를 제시하였다. 지표종분석(Indicator Species Analysis) 결과, 해발고도별 지표종으로 상층식생에서 5분류군, 하층식생에서 18분류군을 선정하였다(p<0.05). 사면방위별 지표종으로는 상층식생 3분류군, 하층식생 16분류군을 선정하였다(p<0.05). 사면경사도별 지표종으로는 상층식생 6분류군, 하층식생 24분류군을 선정하였다(p<0.05). 자생지별 지표종으로는 상층식생 8분류군과 하층식생 65분류군을 선정하였다. 지표종들에 대한 MRPP-test 결과, 상층식생보다 하층식생에서 종조성이 다소 이질적인 것으로 분석되었다. NMS ordination 결과, 상층식생의 암석노출도와 하층식생의 위도에 따라 지표종의 환경적 요인과의 상관관계가 유의한 것으로 나타났다.

• 한국항해항만학회지
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• 제40권5호
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• pp.249-256
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• 2016

The International Association of Marine Aids to Navigation and Lighthouse Authorities(IALA) model course recommends specific aspects of basic curriculums for Vessel Traffic Services(VTS) operator education such as modules, course hours, contents, etc. Most domestic training programs for newly appointed VTS operators comply with such recommendations. The objective of this study is to determine whether such modules for VTS operator training recommended by the current IALA model course correspond to the actual opinions of VTS operators who are currently working in the field. To this end, the relative importance of basic modules for vessel traffic services operator training was analyzed using the Analytic Hierarchy Process(AHP) method. A questionnaire was designed to include 8 modules recommended by the IALA model course, and the survey results of 52 individuals working at 5 VTS centers were analyzed. The result showed that, unlike the assumption by the IALA, domestic VTS operators viewed Nautical Knowledge as the most important modules, followed by Emergency Situations, Traffic Management, Language, Equipment, VHF Radio, Communication Co-ordination, and Personal Attributes, in that order.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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• pp.166-169
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• 1990

The purpose of the circuit breaker on power system is to disconnect the faulty part from the system and to maintain the integrity of the system. With switching overvoltages are generated. When the system voltages become higher, switching overvoltage is important factor in insulation co-ordination. Since the no-load reclosing overvoltage with inductive source is severe, this paper deals with the reclosing overvoltage and the effect of closing resistor. This reclosing overvoltage of 27-bus model system with and without closing resistor is analyzed by using EMTP (Electro-Magnetic Transients Program) for both deterministic and Stochastic model.

• 대한가정학회지
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• 제41권10호
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• pp.199-209
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• 2003

The purpose of this study was to investigate the causes of bankruptcy in small apparel stores. Data were collected from 153 apparel retail store owners who experienced failure in small apparel stores in Busan. The results showed as follows; The internal factors that caused bankruptcy in small apparel stores were the problems related with employees, capital, investment, weak marketing strategies, inadequate management, and characteristics of store owners. The external factors were economic condition, unexpected incidents, and the condition of market. There were significant differences in the perception of factors which caused the store bankruptcy according to prior business experience before opening apparel stores, the level of education, and the period between store opening and closing.