• Title/Summary/Keyword: Stock assessment

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Assessment on Forest Resources Change using Permanent Plot Data in National Forest Inventory (국가산림자원조사 고정표본점 자료를 활용한 산림자원변화 평가에 관한 고찰)

  • Yim, Jong-Su;Kim, Eun Sook;Kim, Chel Min;Son, Yeong Mo
    • Journal of Korean Society of Forest Science
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    • v.104 no.2
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    • pp.239-247
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    • 2015
  • Since 2006, new national forest inventory in Korea has been restructured to assess current status and and monitor the changes in forest resources based on permanent sample plots. The objective of estimate this study is to assess changes in forest resources such as land use/cover categories and forest stand variables. For this study, permanent plot data were collected between 2006-2008 and 2011-2013 in Chungcheongbuk-do, respectively. In order to produce land use/cover change matrix which plays an important role as an activity data for estimating GreenHouse Gas inventory, permanent plots were classified into six land use/cover categories. Additionally, matrixes for assessing the changes in age class and dominant tree species can provide more detailed information. For forest stand variables(tree density, basal area, growing stock, mean diameter at breath height, and mean height), their growth and change were assessed. The periodic annual growth ratios for tree density and basal area were slightly declined whereas that of growing stock was estimated to be about 3.7%. The uncertainty of changes in forest stand variables is less than 5%, except for tree density (RSE: 58%). The variation of tree density is relatively high compared to the other variables.

Policies to Manage Drug Shortages in Selected Countries: A Review and Implications (주요국의 수급불안정 의약품 관리제도에 관한 고찰과 한국에의 시사점)

  • Inmyung Song;Sang Jun Jung;Eunja Park;Sang-Eun Choi;Eun-A Lim;Sanghyun Kim;Dongsook Kim
    • Health Policy and Management
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    • v.34 no.2
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    • pp.106-119
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    • 2024
  • Drug shortage is a persistent phenomenon that poses a public health risk worldwide and occurs due to a range of causes. The purpose of this study is to review key policies to prepare for and respond to drug shortages in selected countries, such as the United States, Canada, and some European countries in order to draw implications. This study reviewed the reports and articles derived from search engines and Google Scholar by using keywords such as drug shortage and stock-out. Over the last decade or so, the United States have strengthened requirements on advance notification for disruption and interruption of drug manufacturing, established the Inter-agency Drug Shortages Task Force to promote the communication and coordination of responses, and expedited drug regulatory processes. Similarly, Canada established the Multi-Stakeholder Steering Committee on drug shortages by involving representatives from central and local governments and private sectors. Canada also adopted a tiered approach to the communication of drug shortages based on the assessment of the severity of the shortage problem and released a detailed information guide on communication. In 2019, the joint task force between the European Medicines Agency and the Heads of Medicines Agencies issued guidelines on drug shortage communication in the European Economic Area. The countries reviewed in this paper focus on communication across different stakeholders for the monitoring of and timely response to drug shortages. The efforts to protect public health from the negative impact of the drug shortage crisis would require multi-sectorial and multi-governmental coordination and development of guidelines.

Assessment of Carbon Sequestration Potential in Degraded and Non-Degraded Community Forests in Terai Region of Nepal

  • Joshi, Rajeev;Singh, Hukum;Chhetri, Ramesh;Yadav, Karan
    • Journal of Forest and Environmental Science
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    • v.36 no.2
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    • pp.113-121
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    • 2020
  • This study was carried out in degraded and non-degraded community forests (CF) in the Terai region of Kanchanpur district, Nepal. A total of 63 concentric sample plots each of 500 ㎡ was laid in the inventory for estimating above and below-ground biomass of forests by using systematic random sampling with a sampling intensity of 0.5%. Mallotus philippinensis and Shorea robusta were the most dominant species in degraded and non-degraded CF accounting Importance Value Index (I.V.I) of 97.16 and 178.49, respectively. Above-ground tree biomass carbon in degraded and non-degraded community forests was 74.64±16.34 t ha-1 and 163.12±20.23 t ha-1, respectively. Soil carbon sequestration in degraded and non-degraded community forests was 42.55±3.10 t ha-1 and 54.21±3.59 t ha-1, respectively. Hence, the estimated total carbon stock was 152.68±22.95 t ha-1 and 301.08±27.07 t ha-1 in degraded and non-degraded community forests, respectively. It was found that the carbon sequestration in the non-degraded community forest was 1.97 times higher than in the degraded community forest. CO2 equivalent in degraded and non-degraded community forests was 553 t ha-1 and 1105 t ha-1, respectively. Statistical analysis showed a significant difference between degraded and non-degraded community forests in terms of its total biomass and carbon sequestration potential (p<0.05). Studies indicate that the community forest has huge potential and can reward economic benefits from carbon trading to benefit from the REDD+/CDM mechanism by promoting the sustainable conservation of community forests.

A study on the estimation of potential yield for Korean west coast fisheries using the holistic production method (HPM) (통합생산량분석법에 의한 한국 서해 어획대상 잠재생산량 추정 연구)

  • KIM, Hyun-A;SEO, Yong-Il;CHA, Hyung Kee;KANG, Hee-Joong;ZHANG, Chang-Ik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.54 no.1
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    • pp.38-53
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    • 2018
  • The purpose of this study is to estimate potential yield (PY) for Korean west coast fisheries using the holistic production method (HPM). HPM involves the use of surplus production models to apply input data of catch and standardized fishing efforts. HPM compared the estimated parameters of the surplus production from four different models: the Fox model, CYP model, ASPIC model, and maximum entropy model. The PY estimates ranged from 174,232 metric tons (mt) using the CYP model to 238,088 mt using the maximum entropy model. The highest coefficient of determination ($R^2$), the lowest root mean square error (RMSE), and the lowest Theil's U statistic (U) for Korean west coast fisheries were obtained from the maximum entropy model. The maximum entropy model showed relatively better fits of data, indicating that the maximum entropy model is statistically more stable and accurate than other models. The estimate from the maximum entropy model is regarded as a more reasonable estimate of PY. The quality of input data should be improved for the future study of PY to obtain more reliable estimates.

Fishing efficiency by vessel capacity of Korean tuna purse seiners operating in the western and central Pacific Ocean (태평양 수역 우리나라 다랑어선망어업의 선박 역량에 따른 조업 효율성 분석)

  • LEE, Mi Kyung;LEE, Sung Il;KIM, Doo Nam;KU, Jeong Eun;KWON, Youjung
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.53 no.2
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    • pp.169-176
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    • 2017
  • Tuna purse seine fishery in the western and central Pacific Ocean (WCPO) has been rapidly developed since early 1980s due to massive investment of major distant water fishing nations, and catch by purse seine fishery operating in the WCPO accounts for nearly half of the world's tuna total catch. As fishing efficiency is reflected by not only improving of individual vessel's capacity but also increasing number of active vessel, it is essential to understand vessel capacity for reliable assessment result on how fishery affects stock status of target species. In this study, fishing efficiency was analyzed by main factors which are representative of vessel capacity using fishing data and vessel information related to Korean tuna purse seine fishery operating in the western and central Pacific Ocean from 1992 to 2014. It showed that fishing efficiency of vessel tends to be higher when having larger vessel tonnage, higher engine power, lower vessel age and larger length of vessel. As for fishing efficiency by set type, CPUE of associated set with floating objects was generally higher than that of free school set, and CPUE of free school set seemed to have a greater effect on engine power and vessel age compared to other factors.

An Alternative Study of the Determination of the Threshold for the Generalized Pareto Distribution (일반화 파레토 분포에서 임계치 결정에 대한 대안적 연구)

  • Yoon, Jeong-Yoen;Cho, Jae-Beom;Jun, Byoung-Cheol
    • The Korean Journal of Applied Statistics
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    • v.24 no.5
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    • pp.931-939
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    • 2011
  • In practice, thresholds are determined by the two subjective assessment methods in a generalized pareto distribution of mean extreme function(MEF-graph) or Hill-graph. To remedy the problem of subjectiveness of these methods, we propose an alternative method to determine the threshold based on the robust statistics. We compared the MEF-graph, Hill-graph and our method through VaRs on the Korean stock market data from January 5, 1987 to August 3, 2009. As a result, the VaR based on the proposed method is not much different from the existing methods, and the standard deviation of VaR for our method was the smallest. The results show that our method can be a promising alternative to determine thresholds of the generalized pareto distributions.

A Study on the Multi-gear and Multi-species Fisheries Assessment Models in Korean Waters II. Single-species by Multiple Fisheries (한국 근해 복수어구 및 다종어업 자원 평가모델 연구 II. 복수어구에 의한 단일 어종 자원의 이용)

  • SEO Young Il;ZHANG Chang Ik
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.34 no.4
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    • pp.359-364
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    • 2001
  • This paper presents case studies on the multi-species fisheries in Korean waters, Multi-species fisheries were divided into two types, that is, multi-species by a single fishery and single species by multiple fisheries. For the case of single species by multiple fisheries, the small yellow croaker stock caught mainly by the Korean pair trawl fishery and the Korean stow net fishery was selected. This approach uses both standardized fishing efforts for the two fisheries by a general linear model and some data for the economic analysis, and then estimates maximum sustainable yield (MSY), maximum economic yield (MEY) and fishing efforts for MSY and MEY, An analysis of interaction aspects between pair trawl and stow net fisheries was carried out to predict the optimal level of fishing effort from the economic point of view, which gives the largest benefits to the two fisheries.

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Assessment of Utilization and Storage Management Practice of Frozen and Refrigerated Foods in School Foodservice -Focus on Meats, Seafoods and Processed Foods- (학교급식에서의 냉장.냉동 축.수산물 및 가공품 이용현황 및 관리실태 조사)

  • Jeong, Hui-Seon;Yun, Ji-Yeong;Bae, Hyeon-Ju
    • Journal of the Korean Dietetic Association
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    • v.13 no.4
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    • pp.345-356
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    • 2007
  • The purpose of this study was to investigate utilization and storage management practice of the frozen and refrigerated foods in school foodservice. 222 dietitians employed in school foodservice were surveyed. In school foodservice, the refrigerated stock farm products and seafoods (78.3%) were more used rather than frozen products (47.5%). According to school foodservice characteristics, the refrigerated meats including dairy products were more frequently used in elementary and middle schools than high school foodservice. On the other hand, the foodservice in high school used more frozen seafoods and processed foods than elementary school did. The data also showed a tendency for the contracted foodservice using more frozen meats and seafoods rather than refrigerated products when comparing with the self-operated foodservice. In terms of receiving conditions, storage methods and storage time, the result indicated that frozen or refrigerated products were often delivered at inappropriate temperature. Especially some products which were needed to be shipped and stored at refrigerated temperature such as mollusks, were delivered and kept at room temperature. The most frequently used thawing method were running water (56.9%), however, the frozen products were often sitted at room temperature for the purpose of thawing. According to the results, several inappropriate handling processes for frozen and refrigerated products were found in school foodservice. In order to improve handling process for frozen and refrigerated products, recognition of food handlers' weakness about storage and distribution, development of radical standards for receiving conditions, storage and thawing methods should be debated.

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STOCK ASSESSMENT OF YELLOW CROAKER IN THE YELLOW SEA AND EAST CHINA SEA (황해및 동지나해의 참조기자원량 해석 -주로 한국기선저인망, 안강망, 유자망, 일본기선저인망 어장을 중심으로-)

  • SHIN Sang Taek
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.8 no.1
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    • pp.11-19
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    • 1975
  • Yellow croaker, Pseudosciaena manchurica Jordan et Thompson, in the Yellow Sea and the East China Sea are subjected to be caught by trawl nets, stow nets and gill nets throughout the year. Monthly indices of population size are calculated. Mathematic models (I) were used in order to determine catchability coefficient, natural mortality, fishing mortality, coefficient coefficient of the fishing ground and dispersion coefficient from the fishing ground. The results are summarized as follows: 1971 1972 1973 $$Catchability\;coefficient\;(C)=1.9369\times10^{-5}\;7.5459\times10^{-6}\;1.2670\times10^{-5}$$ Natural mortality (M) = 0.1645 0.6152 0.4367 Population for the first half season (February 1 to May 31) 1971 1972 1973 Initial\;population=\;107,100M/T 209,100M/T 214,400M/T Dispersion=83,000' 159,700' 133,400' Natural mortailty= 4,700' 32.700' 19,100' Final population= 2,800' 4,500' 49,000' Population for the latter half season (June 1st to the following January 31st) 1971 1972 1973 Initial population= 44,500M/T 67,500M/T 83,800MT Recruitment= 19,000' 183,900' 67,100' Natural mortality= 5,900' 67,900' 38,500' Final population= 37,000' 168,300' 92,400'.

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Assessment of Biomass and Carbon Stock in Sal (Shorea robusta Gaertn.) Forests under Two Management Regimes in Tripura, Northeast India

  • Banik, Biplab;Deb, Dipankar;Deb, Sourabh;Datta, B.K.
    • Journal of Forest and Environmental Science
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    • v.34 no.3
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    • pp.209-223
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    • 2018
  • We investigated tree composition, stand characteristics, biomass allocation pattern and carbon storage variability in Sal forests (Shorea robusta Garten.) under two forest management regimes (Sal forest and Sal plantation) in Tripura, Northeast India. The results revealed higher species richness (29 species), stand density of $1060.00{\pm}11.12stems\;ha^{-1}$ and diversity index ($1.90{\pm}0.08$) in Sal forest. and lower species richness (4 species), stand density of $ 230.00{\pm}37.22stems\;ha^{-1}$ and diversity index ($0.38{\pm}0.15$) in Sal plantation. The total basal cover $33.02{\pm}4.87m^2ha^{-1}$) and dominance ($0.76{\pm}0.08$) were found higher in Sal plantation than the Sal forest ($22.53{\pm}0.38m^2ha^{-1}$ and $0.23{\pm}0.02$ respectively). The total vegetation carbon density was recorded higher in Sal plantation ($219.68{\pm}19.65Mg\;ha^{-1}$) than the Sal forest ($167.64{\pm}16.73Mg\;ha^{-1}$). The carbon density estimates acquired in this study suggest that Sal plantation in Tripura has the potentiality to store a large amount of atmospheric carbon inspite of a very low species diversity. However, Sal forests has also an impending sink of carbon due to presence of large number of young trees.