• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.2
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• pp.109-120
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• 2007

The information on flowpath, storage, residence time, and interactions of water and carbon transport in a catchment is the prerequisite to the understanding and predicting of water and carbon cycling in the mountainous landscapes of Korea. In this paper, along with some up-to-date results, we present the principal methods that are currently used in HydroKorea and CarboKorea research to obtain such information. Various catchment hydrological processes have been examined on the basis of the water table fluctuations, the end-member mixing model, the cross correlation analysis, and cosmogenic radioactive isotope activity. In the Gwangneung catchment, the contribution of surface discharge was relatively large, and the changes in the amount, intensity and patterns of precipitation affected both the flowpath and the mean residence time of water. Particularly during the summer monsoon, changes in precipitation patterns and hydrological processes in the catchment influenced the carbon cycle such that the persistent precipitation increased the discharge of dissolved organic carbon (DOC) concentrated in the surface soil layer. The improved understanding of the hydrological processes presented in this report will enable a more realistic assessment of the effects of climate changes on the water resource management and on the carbon cycling in forest catchments.

• Journal of the Korean GEO-environmental Society
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• v.7 no.3
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• pp.5-19
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• 2006

The secondary consolidation settlement of soft clay is generally very little compared to the total settlement and occurs very slowly during long-term period. However the secondary consolidation settlement is comparatively large amount in organic and heavily compressed clay and is a very important engineering factor. In order to reduce residual settlements in reclaimed soft ground, the preloading method is often used. In this study, in order to determine reasonable long-term settlements of large reclaimed site, laboratory incremental loading consolidation tests and surcharging consolidation tests are performed. Sampling was done at Incheon area of west coast and Gwangyang area of south coast in Korea. The characteristics of secondary consolidation have obtained through laboratory tests and analyzed systematically to predict long-term settlements. Additionally, the location data and laboratory test results are correlated by using GIS(geographic information system). The secondary consolidation settlement of the site was predicted based on D/B and the operation technique and estimation technique of space of GIS.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.325-332
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• 2013

We aimed to determine the quality indicators for quality prediction of frozen green pumpkin in distribution. Freshly harvested green pumpkin slices were blanched under optimal conditions (confirmed in a preliminary experiment), quick-frozen at $-40^{\circ}C$ for 24 h, and stored at 0, -5, -15, and $-25^{\circ}C$. The correlation between each quality characteristic and the sensory preference rate was analyzed. There was a significant correlation between storage temperature-related drip rate and preference rate across all temperatures, except at$-25^{\circ}C$. Hunter values, a and b, showed relatively high correlation coefficient values at -5, -15, and $-25^{\circ}C$. Therefore, a change in the Hunter values should be considered when storing green pumpkin, because of their significant correlation with changes in the sensory preference and drip rates. Furthermore, they should be applied as quality indicators for the quality prediction of frozen green pumpkin in distribution.

• Phonetics and Speech Sciences
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• v.14 no.4
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• pp.45-56
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• 2022

This paper proposes an optimal methodology for automatically diagnosing and predicting the severity of the chronic kidney disease (CKD) using patients' utterances. In patients with CKD, the voice changes due to the weakening of respiratory and laryngeal muscles and vocal fold edema. Previous studies have phonetically analyzed the voices of patients with CKD, but no studies have been conducted to classify the voices of patients. In this paper, the utterances of patients with CKD were classified using the variety of utterance types (sustained vowel, sentence, general sentence), the feature sets [handcrafted features, extended Geneva Minimalistic Acoustic Parameter Set (eGeMAPS), CNN extracted features], and the classifiers (SVM, XGBoost). Total of 1,523 utterances which are 3 hours, 26 minutes, and 25 seconds long, are used. F1-score of 0.93 for automatically diagnosing a disease, 0.89 for a 3-classes problem, and 0.84 for a 5-classes problem were achieved. The highest performance was obtained when the combination of general sentence utterances, handcrafted feature set, and XGBoost was used. The result suggests that a general sentence utterance that can reflect all speakers' speech characteristics and an appropriate feature set extracted from there are adequate for the automatic classification of CKD patients' utterances.

• Neonatal Medicine
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• v.18 no.2
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• pp.240-247
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• 2011

Purpose: The rationale for skin surface cultures is that bacterial colonization precedes infection and, as a result, that identification of a potential pathogen is predictive of later systemic infection in preterm infants. We aimed to analyze results of surveillance surface cultures in extremely low birth weight (ELBW) infants and seek for effective ways of performing surveillance surface cultures. Methods: We analyzed the surveillance surface cultures of 113 ELBW infants over a 4-year period. Surveillance cultures were obtained routinely from five sites: axilla, external ear canal, nasopharynx, throat (or tracheal aspirate if intubated) and anus. Each surface culture obtained during the 13 days, prior to the date of the blood culture, was compared with the blood culture obtained when sepsis was suspected. The sensitivity, specificity and positive predictive value (PPV) of the surveillance cultures were calculated among 1894 blood-surface culture pairs by surface sites, recovered organisms and interval between surveillance samples and blood cultures. Results: The overall sensitivity, specificity and PPV of surface cultures were 45.9, 22.4 and 6.8%, respectively. The PPV was highest for the throat/tracheal cultures (11.0%) and lowest for the anal cultures (2.3%). As the time of culturing progressed toward the day of blood culturing, the sensitivity and specificity of the surface cultures significantly increased. Only axillary and throat/tracheal cultures were useful in predicting the microorganisms causing sepsis. Conclusion: Surface cultures could help to predict sepsis pathogens and infection surveillance in preterm infants could be continued with a reduced number of cultured sites focusing on the axilla and throat/trachea.

• Proceedings of the Korea Association of Information Systems Conference
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• 2003.05a
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• pp.55-73
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• 2003

As the development of wireless technologies continue, mobile stock trading has become a new channel for companies to reach their customers. This study examines the factors affecting customer acceptance of mobile stock trading services. The research model based on the previous studies was established and the research hypotheses were generated. The sample was divided into users and nonuser groups. The test results show that relative advantage and social influence are positively related to intention to accept mobile services as well as in intention to reuse, security risk is negatively related to intention to reuse, frequency of trading is positively related to intention to reuse, cost burden is negatively related to the probability of using mobile stock trading services, and social influence is positively related to the probability of using mobile services. The results also support that information quality and response time are positively related to relative advantage, and interface quality is negatively related to complexity. It is considered that the study results may help managers to increase customer use of mobile stock trading services.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.11
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• pp.6613-6620
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• 2014

In this paper, 228 cooperations supported by government were surveyed on the cognition levels of 5 factors for successful policies that support small business cooperation. Goal importance, awareness stage of importance, and current concerning level were scored to each question of factors. Using the results of previous studies, the maturity of each success factor, and the forecast time to mature and maturity of each question were analyzed. The results were compared with the results of a study precedent. Moreover, the changes in the participants' recognition levels were reviewed between before and after government's support. These comparative studies reflect government policies. Despite the government's supporting policies aided on building cooperation positively, the participants still worry about the decreasing government support. To allay these concerns, government policies should be implemented continuously to promote cooperation rather than a one-time support.

• Journal of Biomedical Engineering Research
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• v.22 no.2
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• pp.151-156
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• 2001

A computer model of the musculoskelotal system that provides accurate prediction of muscle force and body movement trom the stimulation input is desired for the effective control system design in FES. This paper aims to investigate the fundamental properties of the gradual muscle force potentiation that was not included in the previous muscle models, for future development of a model that provides vetter prediction of FES-induced muscle force and body movement. Specifically, hou the muscle length was investigated. The experimental results showed that both the force increment ratio and the time-to-peak during electrical stimulation decreased with stimulatino frequency. When the muscle potentiation state was saturated by preceding stimulation. the force did not increase any more during additive stimulation. Muscle length significantly affected the force potentiation in such a way that the force increment ratio decreased with muscle length. A new model of the muscle potentiation based on these results is desired in the future.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.415-421
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• 2004

막대한 예산을 투입하여 추진하고 있는 지자체 GIS사업은 기술의 발전에 비해 제도, 교육, 사용자의 마인드, 유지관리 활동, 향후 사업 구상 등에서 상대적인 빈곤을 경험하고 있는 것이 사실이다. 이렇듯 신기술이 도입됨에 따라 다양한 제반 여건들이 동반적으로 성숙하지 못함으로 인해 발생하는 현상을 과도기적 현상1)으로 진단하고 있다. 이미 다양한 분야에서 GIS를 도입한 지자체에서는 이러한 과도기적 현상을 극복하기 위해 상당한 어려움을 겪고 있으며, 새롭게 GIS를 도입하고자 하는 지자체에서도 타 지자체에서 모니터링을 통해 간접적으로 과도기적 현상을 경험함으로 인해 효과적인 사업 추진을 구상하는데 상당한 어려움을 겪고 있는 것이 현실이다. 또한 지자체의 경우 중앙정부에서 추진하고 있는 다양한 사업에 영향을 받을 수밖에 없고, 현재의 GIS 사업의 추세가 단순한 공간정보 중심의 사업이 아닌 다양한 속성정보와의 연계를 모색하고 있다는 점에서 지자체 GIS정보화의 방향은 예전과는 사뭇 다른 양상을 간파해 야 하는 현실에 놓여 있다. 이와 같은 지자체 GIS의 과도기적 현상을 극복하기 위해서는 정보기술의 빠른 변화속도와 외부환경의 극심한 환경변화의 상황에서 ‘보이는 것과 보이지 않는 것’의 관계를 진단하고, 변화에 대한 예측과 대비, 중요한 일과 급한 일을 구분한 총체적인 밑그림의 마련과 실행계획의 수립이 우선시 되어야 한다. 지자체 GIS의 문제 해결의 노력이 단숨에 바로 해결되는 것이 아니고, 또한 현재 추진된 사업을 기반으로 중복투자의 방지와 시너지 효과 극대화를 위한 투자의 노력이 장기간의 시간적 개념속에서 진행되어야 한다는 점에서 이를 이끌어줄 가이드가 필요한 것이다. 이러한 총체적인 지자체 GIS의 계획마련을 위해 건설교통부에서는 ‘국가지리정보구축 및 활용등에 관한 법률’상에 계획 수립의 항목을 명문화하고, 나아가 GIS정보화 전략계획 수립에 관한 지침작성을 위한 노력을 진행 중에 있다. 이러한 일련의 현실을 감안하여 지자체 GIS정보화 전략계획 수립을 체계적이고 실질적으로 수립할 수 있는 ‘지자체 GIS정보화 전략계획 수립모델’은 반드시 선행되어야 할 사항임에 분명하다. 지자체 GIS정보화 전략계획 수립 모델은 지자체 GIS정보화 전략계획 수립의 효과로 하고 있으며, 형식적 측면에서는 GIS특성을 반영한 전략계획 수립의 방법론적 측면을 중심으로 구성된다. 이러한 과정을 거처 실제 지자체 GIS정보화 전략계획을 수립하는데 필요한 9단계를 설정하고 각각의 단계에 대한 중심활동을 바탕으로 지자체에서 실제 전략계획 수립에 필요한 지침을 작성하는 것으로 구성되어 있다.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.75-75
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• 2015

오염원과 취수장이 동일 구간 내에 공존하는 국내하천의 특성상, 하천 평면 내에서 오염물의 거동 및 혼합 특성을 보다 정확하게 해석하기 위해서는 2차원 이송-분산 모형의 적용이 필요하다. 이를 위해서는 2차원 모형의 주요 매개변수인 종분산계수와 횡분산계수의 적절한 입력이 매우 중요하다. 하지만 국내외적으로 횡분산계수에 대한 연구는 많이 진행된 반면, 현재까지 종분산계수에 대한 연구는 충분히 이루어지지 않은 실정이다. 분산계수를 결정하는 방법에는 실측된 농도 자료의 유무에 따라 크게 두 가지로 분류된다. 실측된 농도 자료가 없는 경우, 이론식이나 경험식을 이용하는 방법이 있다. 반면에 추적자 실험 등을 수행하여 실측된 농도 자료가 있는 경우, 모멘트법 또는 추적법을 적용하여 농도-시간 분포 곡선으로부터 분산계수를 계산하는 것이다. 모멘트법은 임의 지점에서 농도의 횡분포를 통해 얻을 수 있는 2차 모멘트의 종방향 변화율이 횡분산계수와 비례한다는 원리를 이용한 것이며, 추적법은 상류부의 관측된 농도를 입력자료로 하여 하류부의 농도를 계산한 후 계산된 농도와 실측된 하류부 농도의 비교를 통해 분산계수를 산정하는 방법이다. 본 연구에서는 불규칙한 단면 형상을 가지는 자연하천에서의 2차원 종 횡분산계수를 산정하기 위해서 Baek & Seo(2010)가 제안한 2차원 유관추적법(2D Stream-tube Routing Procedure)을 적용하였다. 본 연구에서는 국내 자연하천 중 다양한 사행형태를 갖으며 수질오염 사고의 위험이 높은 구간을 선정하고, 추적자로서 Rhodamine WT를 이용하여 현장실험을 수행하였다. 실험에서 수집된 수리량 및 농도자료로부터 추적자의 2차원적 거동을 분석하였으며, 2차원 유관추적법을 적용하여 종분산계수를 산정하였다. 그 결과 하폭 대 수심비(W/H)와 마찰손실관련 무차원변수(U/U*)의 증가에 따라 종분산계수가 증가됨을 확인 할 수 있었다. 본 연구에서 산출된 종분산계수와 선행 연구에서 수집된 자료를 이용하여 추정식을 개발하였다. 차원해석을 통해 무차원 종분산계수에 영향을 미치는 무차원 인자를 선별하고 회귀분석을 이용하여 종분산계수 추정식을 유도하였다. 추정식을 이용하여 산정한 종분산계수의 범위는 Elder (1959)가 제안한 이론값보다 약 10배 정도로 크게 나타났다. 혼합 특성이 밝혀지지 않은 자연하천에 2차원 확산모형을 적용하고자 할 때 본 연구에서 개발된 추정식으로부터 계산된 종분산계수를 사용할 수 있을 것이다.