• 한국습지학회지
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• 제13권1호
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• pp.35-44
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• 2011

기후변동에 따른 식생반응 및 그에 따른 물수지 동역학의 변화를 살펴볼 목적으로 본 연구에서는 식생의 물 이용가능성과 식생 생산량의 지역별 연별 변동성을 분석하였다. 유역의 식생 물이용의 대리변수로서 습윤량에 대한 기화량의 비로 표현되는 Horton 지수의 계산을 통하여 유역에서의 수문 분할과 그에 따른 식생의 물 이용 가능성에 대한 정량화를 시도하였다. 연별 Horton 지수의 추정결과 기후의 변동성과 비교하여 볼 때 상대적으로 일정한 값을 유지하고 있는 것을 살펴볼 수 있다. 이와 더불어 Horton 지수와 식생의 강우이용효율을 비교한 결과, 물 이용가능성에 따른 식생의 물 이용에 대한 흥미로운 패턴이 있음을 살펴볼 수 있었다. 물이 식생 성장에 제한요소가 될 경우 식생의 강우이용효율은 공통적인 최대값으로 수렴한다는 선행연구들의 결과를 본 연구를 통해서도 확인할 수 있다.

• 한국작물학회지
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• 제44권2호
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• pp.149-153
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• 1999

Prediction of rice developmental stage is necessary for proper crop management and a prerequisite for growth simulation as well. The objectives of the present study were to find out the relationship between the plastochrone index(PI) and the developmental index(DVI) estimated by non-parametric phenology model which simulates the duration from seedling emergence(DVI=0) to heading(DVI=l) by employing daily mean air temperature and daylength as predictor variables, and to confirm the correspondency of developmental indice to panicle developmental stages based on this relationship. Four japonica rice cultivars, Kwanakbyeo, Sangpungbyeo, Dongjinbyeo, and Palgumbyeo which range from very early to very late in maturity, were grown by sowing directly in dry paddy field five times at an interval of two weeks. Data for seedling emergence, leaf appearance, differentiation stage of primary rachis branch and heading were collected. The non-parametric phenology model predicted well the duration from seedling emergence to heading with errors of less than three days in all sowings and cultivars. PI was calculated for every leaf appearance and related to the developmental index estimated for corresponding PI. The stepwise polynomial analysis produced highly significant square-rooted cubic or biquadratic equations depending on cultivars, and highly significant square-rooted biquadratic equation for pooled data across cultivars without any considerable reduction in accuracy compared to that for each cultivar. To confirm the applicability of this equation in predicting the panicle developmental stage, DVI at differentiation stage of primary rachis branch primordium was calculated by substituting PI with 82 corresponding to this stage, and the duration reaching this DVI from seedling emergence was estimated. The estimated duration revealed a good agreement with that observed in all sowings and cultivars. The deviations between the estimated and the observed were not greater than three days, and significant difference in accuracy was not found for predicting this developmental stage between those equations derived for each cultivar and for pooled data across all cultivars tested.

• Journal of Korea Trade
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• 제27권3호
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• pp.147-160
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• 2023

Purpose - This paper aims to investigate the competitiveness and complementarity of the agricultural products trade between Korea and Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP) countries. The study evaluates the opportunities and challenges that Korea's agricultural sector faces after joining the CPTPP, and suggests strategies to deepen cooperation and expand Korea's agricultural products trade. Design/methodology - To achieve these objectives, we analyze the trade competition and cooperation relationship between Korea and CPTPP countries in the agricultural products trade. This study uses data from Chapters HS1-24 in UN Comtrade from 2012 to 2022, and applies the indices of revealed comparative advantage, export similarity, and trade complementarity to examine the trade dynamics. Furthermore, we use an Autoregressive Integrated Moving Average (ARIMA) model to predict the agricultural products trade complementarity index between Korea and CPTPP countries from 2022 to 2031. Findings - The findings of our analysis reveal that Korea's agricultural products trade competitiveness is weak compared to that of CPTPP countries, and Korea's agricultural products are at a competitive disadvantage. On the whole, the similarity index of agricultural products trade exports between Korea and CPTPP countries is low, the structure of agricultural products export is quite different, and trade competition is relatively moderate. The trade complementarity index between Korea and CPTPP countries is generally high, with strong complementarity and a large space for cooperation and development. The ARIMA model shows that in the next ten years, although the agricultural products trade complementarity index fluctuates, but is generally high, there will still be a complementarity advantage in the future. Originality/value - This study is the first attempt to investigate the competitiveness and complementarity of the agricultural products trade between Korea and CPTPP countries. We also introduce an ARIMA model to forecast and analyze the future agricultural products trade complementarity index. Our study provides new perspectives and solutions for the future development of Korea's agricultural products trade after joining the CPTPP.

• Imaging Science in Dentistry
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• 제54권2호
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• pp.147-157
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• 2024

Purpose: The aim of this study was to explore the correlations of cone-beam computed tomographic findings with the apnea-hypopnea index in patients with obstructive sleep apnea. Materials and Methods: Forty patients with obstructive sleep apnea were selected from the ear-nose-throat (ENT) outpatient clinic, Faculty of Medicine, Mansoura University. Cone-beam computed tomography was performed for each patient at the end of both inspiration and expiration. Polysomnography was carried out, and the apnea-hypopnea index was obtained. Linear measurements, including cross-sectional area and the SNA and SNB angles, were obtained. Four oral and maxillofacial radiologists categorized pharyngeal and retropalatal airway morphology and calculated the airway length and volume. Continuous data were tested for normality using the Kolmogorov-Smirnov test and reported as the mean and standard deviation or as the median and range. Categorical data were presented as numbers and percentages, and the significance level was set at P<0.05. Results: The minimal value of the cross-sectional area, SNB angle, and airway morphology at the end of inspiration demonstrated a statistically significant association (P<0.05) with the apnea-hypopnea index, with excellent agreement. No statistically significant difference was found in the airway volume, other linear measurements, or retropalatal airway morphology. Conclusion: Cone-beam computed tomographic measurements in obstructive sleep apnea patients may be used as a supplement to a novel radiographic classification corresponding to the established clinical apnea-hypopnea index classification.

• 한국유기농업학회지
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• 제21권4호
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• pp.523-538
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• 2013

To help improve the current government practice of direct damage-compensation policies, resulting from the loss of profit, sustained by Hanwoo farmers, as a result of the recent Korea-U. S. Free Trade Agreement (FTA), this research aims to examine any problems or issues caused by said policies. To accomplish this task, we have established Hanwoo-SIMO model and estimated the damage of Hanwoo farmers, one without the implementation of the FTA and another with the FTA, to compare and contrast the two. We then analyzed the efficacy of the current government policies. According to our analysis, the current direct compensation policies for the loss of profit on the part of Hanwoo farmers are insufficient. To address this problem, we recommend the government enact a new direct damagecompensation law to address the following issues. First, as the base formula of damage-compensation, the government should use current price of the beef rather than the annually changing flexible price. Second, the flexible control index should remain fixed at 1.0 rate while the government prepares the adequate amount of the damage compensating direct payment resulting from the FTA. Third, the direct government compensation policy should extend beyond the current 15 years (2013-2026) as the profit loss is expected to increase after the midpoint of the FTA.

• 한국대기환경학회지
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• 제24권6호
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• pp.649-661
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• 2008

The impact of the detailed surface data on regional meteorological fields in complex coastal area is studied using RAMS. Resolutions of topography and land use data are very important to numerical modeling, because high resolution data can reflect correct terrain height and detail characteristics of the surface. Especially, in complex coastal region such as Gwangyang area, southern area in Korean Peninsula, high resolution topography and land use data are indispensable for accurate modeling results. This study investigated the effect of resolutions of terrain data using SRTM with 3 second resolution topography and KLU with 1 second resolution land use data. Case HR was the experiment using high resolution data, whereas Case LR used low resolution data. In Case HR, computed surface temperature was higher than Case LR along the coastline and wind speed was $1{\sim}2m/s$ weaker than Case LR. Time series of temperature and wind speed indicated great agreement with the observation data. Moreover, Case HR indicated outstanding results on statistical analysis such as regression, root mean square error, index of agreement.

• Advances in environmental research
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• 제5권4호
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• pp.213-224
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• 2016

This paper presents a numerical model based on a UTCHEM simulator to simulate surfactant flushing process to remediate diesel contaminated sand column. For this purpose, we modeled remediation process under 10000 and 20000 ppm initial concentrations of diesel. Various percent-mass sodium dodecyl sulfate (SDS) considered in our model. The model results indicated that 0.3 percent-mass of SDS at 10000 ppm and 0.1 percent-mass of SDS at 20000 ppm initial diesel concentration had maximum removal perdition which is in agreement with the experiment results. For 10000 ppm diesel concentrations, the coefficient of determination ($R^2$) and index of agreement (IA) between the model result and the experimental data were 0.9952 and 0.9695, respectively, and for 20000 ppm diesel concentrations, $R^2$ and IA were 0.9977 and 0.9935, respectively. The sensitivity analysis of permeability illustrated that in all diesel concentrations and SDS percent-mass with increasing permeability the model resulted in more removal efficiency.

• 농업과학연구
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• 제45권4호
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• pp.879-888
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• 2018

This research was done to develop a standard management checklist for duck farmers. To this end, experts in commercial duck farming participated in making a blueprint for a standard management checklist. This expert group consisted of ten members which included the researcher, a professor, an extension advisor and leading farmers in commercial duck farming. By collecting knowledge on commercial duck farming from these experts, a management performance index was made, and checking factors were designated. As a result of this expert survey, management outcome indicators and subdivision evaluation indicators were established. To confirm these results, a first stage Delphi expert survey was carried out. As a result, the experts were not in agreement with the farming scale of 1 - 4 levels and 2 levels in the management outcome indicators. Additionally, the experts were not in agreement on the choice of feed in the feeding management and the cooperative management system as well as the utilization of agricultural information in managing the business. The factors that did not have the same opinion among experts were surveyed by a second Delphi survey asking whether experts approve the requested value. As a result of the second Delphi survey, all factors have an approval rate that have a value of more than 90%. Finally, a standard management checklist was established based on the research result.

• 한국농공학회논문집
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• 제66권2호
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• pp.1-12
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• 2024

In order to integrate two consolidation theories of Terzaghi's consolidation theory and Mesri's secondary compression theory and to identify a model suitable for analyzing stress-strain behavior over time, numerical analysis on consolidation tests were conducted using a modified cam-clay model and a soft soil creep model and the following conclusions were obtained. The results of numerical analysis applying the theory that a linear proportional relationship is established between the void ratio at logarithmic scale and the permeability coefficient at logarithmic scale is better agreement with the result of oedometer test than the results of applying constant hydraulic conductivity. The modified cam-clay model is a model that does not include secondary compression, but the slope of the normal consolidation line corresponding to the compression index of the standard consolidation test includes secondary compression, so the actual settlement curve over time is lower than the predicted value through numerical analysis. It always gets smaller. Other previous studies that applied Terzaghi's consolidation theory to consolidation test analysis showed the same results and were cross-confirmed. The soft soil creep model, which includes secondary compression in the theory, showed good agreement in all sections including secondary compression in the consolidation test results. It was judged appropriate to use a soft soil creep model when performing numerical analysis of soft clay ground.

• The Korean Journal of Pain
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• 제25권3호
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• pp.173-182
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• 2012

Background: Fibromyalgia (FM) is characterized by chronic widespread pain with a low pain threshold. The aim of this study was to compare two criteria for the diagnosis and assessment of FM and to analyze the correlation and agreement between the 1990 and 2010 American College of Rheumatology (ACR) preliminary diagnostic criteria for FM. Methods: We studied 98 patients who had already been diagnosed as having FM using the 1990 criteria or 2010 preliminary criteria. Tender point examination, FM impact questionnaire (FIQ) and pain visual analog scale (VAS) were obtained. According to the preliminary criteria, FM was quantified as WPI (widespread pain index) and the SS scale (symptom severity) and the two criteria were compared. Results: Among 98 patients, 78.6% of the patients were diagnosed with the 1990 ACR criteria and 93.9% of the patients were diagnosed with the ACR preliminary diagnostic criteria, and there was also significant agreement between the two criteria (P < 0.01). There was a correlation with the WPI and the tender point, with the SS and the FIQ, and with the sum of the WPI and SS and the FIQ. Conclusions: The ACR preliminary diagnostic criteria for FM were in agreement with the 1990 ACR criteria during the disease course. The preliminary criteria were the more sensitive method than the 1990 criteria. In addition, the 2010 criteria might have advantages since it is easy to assess the physical and psychological symptoms and can be quantified. Therefore, the ACR preliminary diagnostic criteria for FM could be used more conveniently for clinical diagnosis and follow up evaluation after starting management of FM.