• 한국산림과학회지
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• 제94권5호통권162호
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• pp.313-320
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• 2005

This study was performed in a 38-year-old Mongolian pine (Pinus sylvestris L. var. mongolica Litvin) plantation in northeast China. Data were collected from 5 sample trees with different canopy position ranging in DBH from 14.6 cm to 23.8 cm. Sawn speciments that included the biggest knot were taken from the stem below the living crown. Number and distribution of knots per whorl below the living crown were studied by relative height below living crown (RHBC). A linear model expressed as function of whorl age (AGE), whorl height ($H_k$) and the stem diameter at which the whorl was located ($D_k$) was developed to predict the knot diameter and angle. The number of annual rings in four periods and the width of respective zone alone stem were used as dependant variables to analyze the knot develop phases. In average, the number of years from branch birth to ceased forming rings was 7.8, the branches remained alive for 4.2 years without forming annual rings, and branches were occluded 14.4 years after their death. These results can provide abundance branch and knot information so as to describe current and past tree growth dynamic of Mongolian pine plantation.

• 한국패류학회지
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• 제28권2호
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• pp.109-116
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• 2012

In order to understand the effect of introduction of oyster rack culture on natural short-necked clam, Ruditapes philippinarum, stock, we investigated the status of natural clam stock prior to introduction of oyster rack culture at Yeongheung Coast of Wando Island. The growth equation of the clam was estimated as: $L_t=61.46{\cdot}(1-e^{-0.172(t+0.155)})$ from ring radius composition of shell. Instantaneous coefficient of total mortality and natural mortality were calculated as: 2.4087/year and 0.478/year, respectively. The age at first capture was estimated to be 2.55 year. The total biomass was estimated to 3.23 ton in the bed (0.8 ha). Applied by these parameters, the annual recruit biomass and the current yield per recruit (Y/R) was corresponded to $114.7individuals/m^2$ and $92.0g/m^2$, respectively. Maximum sustainable yield (MSY) was estimated 0.77 ton/year which was close to annual catches, 0.74 ton/year, in the area.

• 한국패류학회지
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• 제24권3호
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• pp.189-197
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• 2008

In order to develop the sustainable ecological management, short-necked clams, Ruditapes philippinarum, were collected from Yoengi coast in Tongyoeng, Korea. The growth of the clam was estimated as: $L_f=68.08{\cdot}(1-e^{-0.145(t+0.324)})$ from ring radius composition of shell. Instantaneous co-efficiency of total mortality and natural mortality were calculated as: 0.991/year and 0.494/year, respectively. The age of the clams from the first capture was estimated to be 3.28. The total biomass was estimated to be 212 MT in the fisheries area (6.4 ha). Applied by these parameters, the annual recruit biomass and the current yield per recruit were calculated to be 649.5 individual/$m^2$ and $0.7\;g/m^2$, respectively. The current fishing intensity was much lower for maximum sustainable yield and acceptable biological catch. Although higher yield per recruit could be achieved by increasing fishing intensity, it is favorable to retain the current fishing intensity because of the unique fishing attitude on Yeongi coast in Tongyoeng, Korea.

• Journal of Ecology and Environment
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• 제33권4호
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• pp.333-341
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• 2010

The objective of our study was to investigate the major reasons for the different growth and visible injury on the needles of black pine growing in Ulsan and Yeocheon industrial complex areas, South Korea. After 12 years of growth, we collected climatic and air pollutant data, and analyzed soil properties and the physiological characteristics of black pine needles. Annual and minimum temperatures in Ulsan were higher than those in Yeocheon from 1996 to 2008. Ozone ($O_3$) was the pollutant in greatest concentration in Yeocheon, and whereas the $SO_2$ concentration in most areas decreased gradually during the whole period of growth, $SO_2$ concentration in Yeocheon has increased continuously since 1999, where it was the highest out of four areas since 2005. Total nitrogen and cation exchange capacity in Yeocheon soil were significantly lower than those of Ulsan. The average growth of black pine in Yeocheon was significantly smaller than that in Ulsan, and the growth of damaged trees represented a significant difference between the two sites. Photosynthetic pigment and malondialdehyde content and antioxidative enzyme activity in the current needles of black pine in Yeocheon were not significantly different between damaged and healthy trees, but in 1-year-old needles, there were significant differences between damaged and healthy trees. In conclusion, needle damage in Yeocheon black pine can be considered the result of long-term exposure to oxidative stress by such as $O_3$ or $SO_2$, rather than a difference in climatic condition or soil properties, and the additional expense of photosynthate needed to overcome damage or alleviate oxidative stress may cause growth retardation.

• Asian Journal of Atmospheric Environment
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• 제5권4호
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• pp.205-215
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• 2011

Ozone ($O_3$) is a main component of photochemical oxidants and a phytotoxic air pollutant. Although the current levels of tropospheric $O_3$ in East Asia could adversely affect productivity of forest tree species, risk assessments of $O_3$ impact were limited. In this paper, we summarize the methodology of risk assessment of $O_3$ on forest tree species based on our two previous studies, risk assessments of $O_3$ impact on the growth of Fagus crenata by Watanabe et al. (2012) and on the annual carbon absorption of three representative conifers, Cryptomeria japonica, Pinus densiflora and Larix kaempferi by Watanabe et al. (2010). $O_3$ sensitivity of each tree species obtained from an experimental study, $O_3$ exposure and atmospheric N deposition based on field monitoring and vegetation survey were integrated by geographic information system method. Based on the results, we conclude that the area with high risk of $O_3$ impact does not necessarily correspond to the area with high $O_3$ exposure. The varieties of tree habitat, tree sensitivity to $O_3$ and annual carbon absorption among the tree species, and N deposition-induced change in the $O_3$ sensitivity of F. crenata are raised as the factors of discordance between areas with high risk and those with high $O_3$ exposure. In the last part of this paper, we discuss the present uncertainty and perspectives of risk assessment for the future studies on the impact of $O_3$ on forest tree species in East Asia.

• 한국수자원학회논문집
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• 제51권9호
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• pp.747-759
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• 2018

다변량 빈도해석과 지역빈도해석의 장점을 동시에 가지는 다변량 지역빈도해석은 다양한 변수를 고려함으로써 수문 현상에 대하여 많은 정보를 얻을 수 있고 많은 가용 자료 수로 인하여 높은 정확도의 분석결과를 도출할 수 있다. 현재까지는 우리나라의 강우 자료를 이용하여 다변량 지역빈도해석이 시도된 적이 없어 국내의 강우 자료를 대상으로 다변량 지역빈도해석의 적용성을 검토할 필요가 있다. 본 연구에서는 다변량 지역빈도해석의 매개변수 추정, 최적 분포형 선정, 확률수문량 성장곡선 추정 등에 집중하여 이변량 수문자료인 연 최대 강우량-지속기간 자료에 대하여 이변량 지역빈도해석의 적용성을 평가하였다. 기상청 71개 지점에 대하여 분석을 실시하였다. 본 연구를 통해 적용된 지역강우자료의 최적 copula 모형으로는 Frank와 Gumbel copula 모형이 선택되었고 주변분포형에 대해서는 지역별로 Gumbel과 대수정규분포와 같은 다양한 분포형이 최적 분포형으로 선택되었다. 상대제곱근오차(relative root mean square error)를 기준으로 지역빈도해석이 지점빈도해석보다 안정적이고 정확한 확률수문량 곡선 추정을 하였다. 이변량 강우분석에서 지역빈도해석을 적용하면 안정적인 수공구조물 설계기준 제시와 강우-지속기간 관계를 모형화 할 수 있을 것으로 기대된다.

• 대한물리치료과학회지
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• 제21권1호
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• pp.21-35
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• 2014

Background : This study aims to examine actual conditions of college students' life, behaviors to prepare for employment, and employment performance, thereby providing basic materials to create efficient measures for college students' employment strategies. Method : The subjects of this study were 207 graduates from the Department of Physical Therapy employed in medical and health institutions in Gyeongsangnam-do and Busan. Aquestionnaire devised by Yu Yeon-wha and Lim Gyeong-ae(2012, 2011) was revised and complemented into a self-reporting questionnaire composed of 29 questions. The collected data was analyzed using SPSS Win 18.00 program. Results : 1) The biggest reason for the respondents' selecting physical therapy as a major was bright prospect for employment, and the largest percent of the respondents answered that they started to prepare for employment in the second semester of junior year. 2)Regarding behaviors to prepare for employment, those who largely provided information on employment were the respondents' seniors and friends. 62.3% of the respondents owned certificates and diplomas. 59.9% took part in programs related to employment in order to prepare for employment. Their weakest area was English and what they wanted to know most was annual salaries provided by companies. They put self-development and growth potential before everything as what should be considered in priority when getting a job. 3)The most frequently asked question in their interviews for employment was the motive for application. The biggest reason for their employment at their current institution was their good personality and manner. 4)As for employment performance, they were unsatisfied with their current average annual salary. Conclusion : School should provide consciousness education and employment coaching so that students can early prepare for employment with an active attitude. In particular, educational environment where many students can gain easy access to information about employment in diverse areas should be provided and student coaching should be actively conducted.

• 한국농림기상학회지
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• 제18권3호
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• pp.109-119
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• 2016

본 연구는 우리나라의 대표 활엽수종 중의 하나인 신갈나무를 대상으로 기후변화에 의한 연도별 생장도일의 변화가 잠재분포 및 생장에 미치는 영향을 평가하기 위해 수행하였다. 이를 위해 신갈나무 분포 지역의 기후특성을 반영한 군집분석을 실시하였으며, 그 결과 7개의 기후군집으로 분류되었다. 각 군집에 포함된 시군에서 수집된 일평균기온 자료를 기반으로 1951년부터 2010년까지 60년 동안의 연도별 생장도일과 기온효과지수를 산출함으로써 시간 경과에 따른 신갈나무의 잠재분포 범위와 생장의 변화 추이를 평가하였다. 이와 함께 기후변화 시나리오 RCP 4.5와 RCP 8.5를 적용하여 2011년부터 2100년까지 연도별 생장도일과 온도효과지수를 산출하여, 기후변화에 의한 신갈나무의 잠재분포 범위와 생장의 변화를 예측하였다. 신갈나무가 현재 분포하고 있는 지역의 생장도일을 연도별로 산출하여 비교한 결과 위도와 해발고도가 낮은 지역은 시간이 경과함에 따라 신갈나무에 적합한 생육가능 범위를 벗어나는 것으로 분석되었다. 특히 기후변화 시나리오를 적용할 경우 지속적인 기온의 상승으로 인해 2050년 이후에는 잠재분포의 변화뿐만 아니라 생장에도 큰 지장을 주는 것으로 평가되었다.

• 대한한의학회지
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• 제36권4호
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• pp.35-41
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• 2015

Objectives: This study aimed to provide basic information for the trend of individual-authorization on functional food materials in Korea to side of Korean medicine. Methods: Approval of materials for individual-authorized functional food in Korea was analyzed from 2004 to August 2015 using database from Ministry of Food and Drug Safety (MFDS), regarding the kinds of function, materials and their functional level by year. Results: Korean functional food market has rapidly grown to 1.56 trillion Won in 2014, with about 10% of annual growth rate. In particular, the increase of individual-authorized functional food is worth of notices, in detail 313 kinds of functional materials covering 31 body functions have been approved by August 2015. 15.7% of individual-authorized functional foods have used the herbal materials. This quantitative and qualitative expansion of functional foods, especially of individual-authorized functional foods, will affect the herbal drug industry negatively. Conclusion: This study figured out the current pattern of material approval for individual-authorized functional food in Korea, which would be essential in development of strategies by Korean medicine community in order to overcome such conditions.

• 한국항해항만학회지
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• 제27권3호
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• pp.315-320
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• 2003

Since the beginning of open-door policy, China has been making rapid annual growth with an average 10% economic development. And due to this rapid growth, cargo volumes via ports have been also rapidly increased, and accordingly, current China government has intensively invested in port development. Further, this development project is significantly big scale, compared with those project which Korea and Japan have. Thus, China is beginning to threaten Korean ports, especially Busan port which try to be a hub port in Northeast Asia. For this reason, it has been very important issue for Korea and Busan port to investigate or analyze Chinese ports based on empirical data. Especially, although various studies related to Shanghai and Hong Kong have been conducted, the competitiveness of overall Chinese major ports has been little studied. In this paper, we analyzed competitiveness level of eight Chinese ports with capabilities as container terminal, based on reliable sources. From data analysis, eight Chinese ports were classified into four groups according to competitiveness level. Rankings among four clusters based on competitiveness level are cluster(Hone Kong), cluster C(Shanghai), cluster A(Qingdao, Tianjin, and Yantian) and cluster D(Dalian, Shekou, and Xiamen).