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Validation of Suitable Zooplankton Enumeration Method for Species Diversity Study Using Rarefaction Curve and Extrapolation (종 다양성 평가를 위한 호소 생태계 동물플랑크톤 조사 방법 연구: 희박화 분석(rarefaction analysis)을 이용한 적정 시료 농축 정도 및 부차 시료 추출량의 검증)

  • Hye-Ji Oh;Yerim Choi;Hyunjoon Kim;Geun-Hyeok Hong;Young-Seuk Park;Yong-Jae Kim;Kwang-Hyeon Chang
    • Korean Journal of Ecology and Environment
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    • v.55 no.4
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    • pp.274-284
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    • 2022
  • Through sample-size-based rarefaction analyses, we tried to suggest the appropriate degree of sample concentration and sub-sample extraction, as a way to estimate more accurate zooplankton species diversity when assessing biodiversity. When we collected zooplankton from three reservoirs with different environmental characteristics, the estimated species richness (S) and Shannon's H' values showed different changing patterns according to the amount of sub-sample extracted from the whole sample by reservoir. However, consequently, their zooplankton diversity indices were estimated the highest values when analyzed by extracting the largest amount of sub-sample. As a result of rarefaction analysis about sample coverage, in the case of deep eutrophic reservoir (Juam) with high zooplankton species and individual numbers, it was analyzed that 99.8% of the whole samples were represented by only 1 mL of sub-sample based on 100 mL of concentrated samples. On the other hand, in Soyang reservoir, which showed very small species and individual numbers, a relatively low representation at 97% when 10 mL of sub-sample was extracted from the same amount of concentrated sample. As such, the representation of sub-sample for the whole zooplankton sample varies depending on the individual density in the sample collected from the field. If the degree of concentration of samples and the amount of sub-sample extraction are adjusted according to the collected individual density, it is believed that errors that occur when comparing the number of species and diversity indices among different water bodies can be minimized.

An Appraisal on the MAGPs for the EU's Fishing Industry (EU의 어업구조조정을 위한 다년도지도프로그램(MAGP)에 대한 평가)

  • Shin Yong-Min;Lee Sang-Go
    • The Journal of Fisheries Business Administration
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    • v.37 no.1 s.70
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    • pp.121-142
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    • 2006
  • EU는 당면과제인 과잉 어획능력을 해소하기 위해 공동어업정책하 어업구조정책의 하나로 '다년도지도프로그램(Multi Annual Guidance Programmes: MAGPs)'을 시행해 왔다. 지난 1983년부터 2002년까지 시행된 MAGP는 EU의 어업구조정책의 핵심 요소이다. 이러한MAGP는 최초 EU의 공공원조계획을 위한 체제의 하나로 입안되었으며, 그 목적은 어선 톤수와 마력수에 대한 각 회원국 어선의 능력을 동결하고자 하는 것이었다. 회원국들은 $4{\sim}5$년 주기로 각 국의 어선개발에 대한 정밀한 계획을 세워야하며, 어선의 용량(총톤수와 엔진출력)과 어획노력에 관한 목표들을 달성하도록 되어 있다. 이러한 감소 목표들은 독립된 과학적 조사결과에 따라 EU 위원회에 제안되고, 공동체 선박등록부에 의거 각국의 프로그램에 대한 적정 실현여부를 감시받고 있다. 또한 각 회원국들은 매년 4월 1일까지 EU위원회에 당해 MAGP의 실현에 대한 진도보고서를 제출하는 식으로 운영되어 왔다. 현재까지 4개의 MAGP가 시행되었다. 제1세대 MAGP(1983-1986년)는 회원국들에 강제적인 것은 아닌 관계로 별다른 성과가 없었으나, 공동체 어선들간의 어획능력 증가 경쟁에 대한 제어의 표현으로 의미가 있었다. 제2세대 MAGP(1987-1991년)에서는 처음으로 진출입 제어를 위한 매우 제한된 법규정이 만들어졌으며, 제3세대 MAGP(1992-1996년)에서는 공동체 어선 감소의 실제목표를 수여하는 첫 번째 계획이었다. 그리고 이 계획은 약 15%정도의 매 우 실질적인 어획능력 감소를 이루었다. 가장 최근에 끝난 4세대 MAGP(1997-2002)는 공동어업정책의 개혁 시간을 주기 위하여 1년 연장되었으며, 이 시스템은 만약 어선의 어획구성상 감소되는 어족자원의 비율이 낮으면 그 자원을 보호하고자 하는 것이었으나, 그 성과는 매우 낮았다. 이 4세대 계획의 또 다른 중요한 혁신은 회원국이 그들의 어선의 활동규제와 크기를 결합시키거나, 또는 전적으로 표본어선의 수익성 분석을 통해 어획능력을 제거하고자 하는 것이다. 그러나 이 역시 관리와 통제의 곤란으로 별 다른 성과를 거두지 못한 것으로 평가받고 있다. 그러나 많은 어려움과 제도상 불완전함에도 불구하고 MAGP는 일정한 효과를 거둔 것으로 보고되고 있다. 즉 어획능력은 지난 20년동안 전체적으로 25% 가량 감소하였으며, 특히 오래되고 비효율적인 어선에 대한 감척으로 어획능력 감소에 기여한 것으로 평가되고 있다. 이들 프로그램은 특히 보조금을 통해 어선의 제3국 영구이전과 낡고 비효율적인 어선의 신조를 가속화시킨 것으로 보고되고 있다.

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Analysis on the Effect of Greenhouse Humidity Control by Counter-flow Ventilator in Winter (동절기 대향류형 환기장치의 온실 내 습도 조절 효과 분석)

  • Lee, Taeseok;Kang, Geumchoon;Jang, Jaekyung;Paek, Yee;Lim, Ryugap
    • Journal of Bio-Environment Control
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    • v.29 no.3
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    • pp.259-264
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    • 2020
  • In this study, the humidity control effect of a counter-flow ventilator was analyzed in a greenhouse with high relative humidity at night in the winter season. A case of the counter-flow ventilator was 0.96 × 0.65× 0.82(W × D × H, m) and there were heat transfer element and two fans for air supply and exhaust in the counter-flow ventilator. Two counter-flow ventilators were used in this study and the setting humidity of the ventilators was 80%. The temperature and relative humidity at night(18:00-8:00) in the greenhouse were measured. In a greenhouse without a counter-flow ventilator, the average temperature and humidity was 14.9℃, 82.8%, respectively. When the counter-flow ventilator was operated, the corresponding averages were 15.1℃, 79.9%. The independent sample t test of monthly temperature and relative humidity showed no difference in temperature, and a significant difference in relative humidity with 1% of the significance level. Therefore, using the counter-flow ventilator helps to control relative humidity in greenhouse and increase yield.. And further research considering the pros and cons of using the counter-flow ventilator is needed.

Estimations of Forest Growing Stocks in Small-area Level Considering Local Forest Characteristics (산림의 지역적 특성을 고려한 시군구 임목축적량 통계 산출 기법 개발)

  • Kim, Eun-Sook;Kim, Cheol-Min
    • Journal of Korean Society of Forest Science
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    • v.104 no.1
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    • pp.117-126
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    • 2015
  • Forest statistics of local administrative districts have many social needs, nevertheless we have some difficulties for working out an accurate statistics because of insufficient data in small-area level. Thus, new small-area estimation method has to set aside additional data, decrease errors of statistics and consider the local forest characteristics at the same time. In this study, we researched the spatial divisions that can set aside additional data for statistics production and satisfy the major premise, which is "forest characteristics of spatial divisions have to be equal to that of small-area". And we compared synthetic estimation methods based on three different spatial divisions(provinces, neighbor districts and new expanded districts). New expanded districts were divided based on the criteria of climate, soil type and tree species composition that affects local forest characteristics. Small-area statistics were assessed in terms of the ability to estimate local forest characteristics and consistency within large-area statistics. As a result, new expanded districts synthetic estimation was assessed to calculate statistics that reflects local forest characteristics better than other two estimation methods. Moreover, this synthetic estimation method produced the statistics that was included within 95% confidence interval of large-area statistics and was the closer to large-area statistics than the neighbor districts synthetic estimation.

An Uncertainty Analysis of Calculating Life Cycle Maintenance and Energy Costs for Technical Proposals (기술제안입찰을 위한 유지관리 및 에너지 비용 산출방식의 불확실성 분석)

  • Chung, Sung Young;Kim, Sean Hay
    • Korean Journal of Construction Engineering and Management
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    • v.19 no.5
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    • pp.3-9
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    • 2018
  • Although Life Cycle Cost (LCC) must be evaluated by experts, sometimes it may not allow a sufficient time for even the experienced LCC expert to make rational decisions. Therefore, it often ends with relatively comparing the final numbers. We have broken down 110 technical proposals that are actually bade and accepted for large construction projects, and then have analyzed the uncertainty of Maintenance and Energy (M&E) cost during building life cycle, which turns out be the most volatile factor in uncertainty of LCC. Also we suggest "Value Engineering Index (VEI)" - the reduced M&E cost that is normalized by the reduced first cost. It is analyzed that the most uncertain factors of the M&E cost include repair and replacement term differing from each project, duplicated repair and replacement, non-standard repair items, and site-specific energy cost. Eventually we propose a VEI population with a mean of 1.38 and a standard deviation of 1.19, which is obtained by individually and exclusively applying the uncertain factors of the M&E cost to the 35 standard sample of technical proposals. The LCC evaluators may be able to use the VEI population as the benchmark to select the technical proposal with the most reasonable LCC among many others in two suggested manners; the one is to deterministically calculate the probability of single VEIs, and the other is to stochastically calculate the probability of the VEIs where uncertainty is quantified.

A Study on Electron Dose Distribution of Cones for Intraoperative Radiation Therapy (수술중 전자선치료에 있어서 선량분포에 관한 연구)

  • Kang, Wee-Saing;Ha, Sung-Whan;Yun, Hyong-Geun
    • Progress in Medical Physics
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    • v.3 no.2
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    • pp.1-12
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    • 1992
  • For intraoperative radiation therapy using electron beams, a cone system to deliver a large dose to the tumor during surgical operation and to save the surrounding normal tissue should be developed and dosimetry for the cone system is necessary to find proper X-ray collimator setting as well as to get useful data for clinical use. We developed a docking type of a cone system consisting of two parts made of aluminum: holder and cone. The cones which range from 4cm to 9cm with 1cm step at 100cm SSD of photon beam are 28cm long circular tubular cylinders. The system has two 26cm long holders: one for the cones larger than or equal to 7cm diamter and another for the smaller ones than 7cm. On the side of the holder is an aperture for insertion of a lamp and mirror to observe treatment field. Depth dose curve. dose profile and output factor at dept of dose maximum. and dose distribution in water for each cone size were measured with a p-type silicone detector controlled by a linear scanner for several extra opening of X-ray collimators. For a combination of electron energy and cone size, the opening of the X-ray collimator was caused to the surface dose, depths of dose maximum and 80%, dose profile and output factor. The variation of the output factor was the most remarkable. The output factors of 9MeV electron, as an example, range from 0.637 to 1.549. The opening of X-ray collimators would cause the quantity of scattered electrons coming to the IORT cone system. which in turn would change the dose distribution as well as the output factor. Dosimetry for an IORT cone system is inevitable to minimize uncertainty in the clinical use.

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Comparative Analysis of Price Sensitivity for Using Environmental-Friendly Agricultural Products in University Foodservices Between Jeonnam and Gyeongnam Areas in Korea (대학급식의 친환경 농산물 이용에 대한 전남.경남지역 대학생의 가격민감성 비교)

  • Lee, So-Jung;Kim, Hyun-Ah
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.8
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    • pp.1220-1230
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    • 2010
  • The purposes of this study were to compare price sensitivity analysis for using environmental-friendly agricultural products in university foodservice between Jeonnam and Gyeongnam areas in Korea and to suggest the optimum guideline for price increase. The questionnaires were distributed to 600 university students respectively in Jeonnam and Gyeongnam area from July 15 to July 25, 2008; among them, 570 students from Jeonnam area and 490 students from Gyeongnam area responded. The results of this study were as follows. First, Indifference price (IDP) were 890 won (Jeonnam area) and 1,050 won (Gyeongnam area); Optimum price point (OPP) were 1,030 won (Jeonnam area) and 1450 won (Gyeongnam area). Price stress range were 140 won (890~1030 won) in Jeonnam area and 400 won (1050~1450 won) in Gyeongnam area. Second, point of marginal cheapness (PMC) were 500 won (Jeonnam area) and 790 won (Gyeongnam area) whereas point of marginal expensiveness (PME) were 1,170 won (Jeonnam area) and 1820 won (Gyeongnam area). Range of acceptable price (RAP) were 670 won (500~1170 won) in Jeonnam area and 1030 won (790~1820 won) in Gyeongnam area. Third, on the basis of IDP percentage and RAP, students in Jeonnam area were more sensitive to meal price increase than students in Gyeongnam area. In contrast, on the basis of Price Stress, students in Gyeongnam area were more sensitive to meal price increase than students in Jeonnam area. Hence, when using environmental-friendly agricultural products in university foodservice, in Jeonnam area, meal price increase should be recommended to be in RAP (500~1170 won), and in Gyeongnam area, meal price increase should be recommended to be in RAP (790~1820 won).

A Comparative Study on the Measurement Model of Anti-Corruption Index : Anti-Corruption Index and CCEJ's Corruption Index (부패지수 측정모형에 대한 비교연구 : 서울시 시정청렴성지수 측정모형과 경실련 부패지수 측정모형을 중심으로)

  • Park, Yong-Chie;Lee, Chung-Min
    • Survey Research
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    • v.6 no.1
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    • pp.1-38
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    • 2005
  • Considering the importance of corruption index measurement model and the diffusion of popular awareness about the importance of anti-corruption, this research compared and analyzed existing corruption index measurement models. This paper has selected "Anti-Corruption Index model(ACI model)" that was developed by Seoul Development Institute and "CCEJ's Corruption Index model" which is under use by the Citizens' Coaltion for Economic Justice. These two models were analyzed in terms of appropriateness of 'the indicator and index choice method', 'the research design' and 'the use of statistical data'. This analysis shows that two models have some problems. First, at the level of indicator and index choice method, the indicators of CCEJ's corruption index model is too atomized and redundant. As not putting weight of indicator, it did not consider importance of each indicator. Citizens who evaluated the level of corruption didn't participate in the weight evaluation team, which results in failure of the model to reflect the citizens' opinion. Also, because the question about Seoul Metropolis' corruption level is not included, it is not detected difference between real corruption level and perceptive corruption level. Second, in terms of appropriateness of research design, the sample of the CCEJ' corruption index model is too small to get credibility. The objectivity of research method seems to be low because survey was performed by exit interview. In addition, 38 items are overfull in the questionnire of CCEJ's corruption index model compare to 13 items in ACI model. Also, in making up questions, the terms are redundant and unobvious. Third, in regarding with feasibility of the statistical data, the CCEJ's corruption index model uses regulation data for disciplinary punishment of 25 local governments in Seoul from 1995 to 1999. But, it is common ideas of scholars that statistical data indicates the tip of an iceberg in corruption. So for using a statistical data, it needs a data of enough quantity and has a high level credibility. In addition, objective method of giving weight is not developed. In this point of view, the use of statistical data has some limits. To solve this problem, ① objective data should be included in the indicators, ② various indicators should be developed and ③ a method of giving weight should be improved.

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A Study on the Effect of the Thematic Audit Review on Conservative Accounting of Unbilled Revenue (테마감리가 미청구공사의 보수적 회계처리에 미치는 영향에 관한 연구)

  • Park, Yeon Ho;Um, Jae Yeon;Jeon, Seong Il
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.16 no.2
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    • pp.177-188
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    • 2021
  • On December 2015, Financial Supervisory Service(FSS) announced the four key thematic audit review areas, one of them is an appropriation of unbilled revenue. Accounting of unbilled revenue is intertwined with a percentage of completion, that is concerned about discretionary decision by manager. Therefore, if manager motivated by income-increasing manipulation is exaggerating percentage of completion, unbilled revenue is excessively recognized. This problem is caused the serious accounting issues(e.g., shock at a loss for 2013 fiscal year by some construction firms, malpractice of accounting in order-made production industry). Distrust of accounting was grown because the shipbuilding and construction industries successively went poor management and bad accounting of them is revealed. Those accounting issues were the trigger for problem recognition of unbilled revenue, they were background for the designation of appropriation unbilled revenue as thematic audit review areas by FSS. Therefore, this study verified effectiveness of thematic audit review by empirically analyzing whether designation of thematic audit review makes the firm increases conservative behavior. Conservative accounting is estimated by using Basu(1997) model. We analyzed the effect of the thematic audit review on conservative accounting of unbilled revenue by comparing with reflecting unbilled revenue or not. The sample for test consists of firm-years the manufacturing and construction industries from 2012 to 2017. The test results of this study suggested that the conservative accounting of unbilled revenue after designation of the thematic audit review was significantly increased. We also tested again by classifying whether or not it is construction industry. We found that construction industry is more conservative than the other industry only for the designated year of the thematic audit review, otherwise there was not any evidence for significantly increasing conservatism. This study contributes to the literature by empirically analysing relationship of the unbilled revenue to the thematic audit review from the perspective of the conservatism and verifying effectiveness of the thematic audit review.

Study on Body Mass Index (BMI), Dietary Intake Attitudes, and Nutrient Intake Status according to Sugar-Containing Food Intake Frequency of College Students in Gyeonggi-do (경기지역 일부 대학생의 가당식품 섭취빈도에 따른 BMI, 식이섭취태도 및 영양소 섭취상태에 관한 연구)

  • Ahn, Sun-Choung;Kim, Yoon-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.11
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    • pp.1649-1657
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    • 2016
  • The purpose of this study was to investigate the body mass index (BMI), dietary intake attitudes, and nutrient intake status according to sugar-containing food intake frequency of 409 college students in Gyeonggi-do. Subjects were categorized into three groups according to sugar-containing food intake frequency: rare intake group (n=113), average intake group (n=195), and frequent intake group (n=101). The average height and weight (P<0.001) of each group were $163.8{\pm}0.11cm$ and $52.9{\pm}8.6kg$, $164.4{\pm}0.1cm$ and $56.2{\pm}6.4kg$, and $167.9{\pm}0.1cm$ and $68.0{\pm}15.7kg$, respectively. The average BMIs of the groups were $19.6{\pm}2.3$, $20.7{\pm}0.8$, and $24.0{\pm}2.7$, respectively (P<0.001). Dietary intake attitude scores of the groups were $30.73{\pm}5.68$, $30.11{\pm}5.51$, and $28.00{\pm}5.31$, respectively (P<0.001). As a result of nutrient intake status, daily averages of energy and carbohydrate intake of the frequent intake group were significantly higher than those of the rare intake group (P<0.05). On the other hand, vitamin A, vitamin $B_1$, and vitamin C intakes of the rare intake group were significantly higher than those of the frequent intake group (P<0.05). Using multiple regression analysis, we found that BMI was the most significant variable affecting sugar-containing food intake. Therefore, nutrition education is necessary to improve nutrient intake while considering sugar intake for maintenance of healthy weight.