• 콘크리트학회논문집
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• 제27권4호
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• pp.331-341
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• 2015

본 연구는 섬유보강 콘크리트의 실무 적용을 위한 성능 평가에 대해 재료 시험으로 낭비되던 시간과 노력을 최소화하고 적용에 있어서의 이론적인 배경을 확보하기 위해, 기존의 가이드라인 및 시험 기준에 따른 실험 결과의 수집과 통계적 분석을 통한, 콘크리트의 압축강도에 기반한 주요 특성들을 특정하기 위해 수행되었다. 섬유보강콘크리트는 다양한 변수에 영향을 받게 되므로 이론적인 접근이 어려운 측면이 있어 본 연구에서는 현재 실무에서 다방면으로 사용되고 있는 100MPa 이하의 압축강도를 가지는 콘크리트를 중심으로 0.25%에서 2% 사이의 강섬유 혼입량에 대한 압축강도와 인장강도 시험을 수행하였다. 인장강도 시험은 표준기관에서 정하고 있는 시험방법인 쪼갬인장강도와 휨인장강도에 대해 수행하였다. 섬유보강콘크리트의 재료시험 결과 쪼갬인장강도와 휨인장강도 모두 압축강도의 증가에 따라 증가하는 추세를 보였으며 강도의 증진률은 압축강도 증가와 함께 감소하는 추세를 보였다. 또한섬유의 혼입량 증가는 인장강도의 증가를 유발하는 것을 확인할 수 있었으며, 압축강도 증가에 따른 인장강도 증진률 감소를 막아 콘크리트 압축강도 증가에 선형적으로 인장강도가 증가하도록 해주는 것을 확인할 수 있었다. 기존 연구들로부터 구축한 데이터베이스를 통한 섬유보강콘크리트의 기계적 성질에 대한 검토를 수행하였다. 다양한 변수에 따른 인장강도의 추정을 위해 인공신경망을 적용하였다. 인공신경망은 multi layer perceptron으로 구성하였으며 전달함수로는 sigmoid 함수를 사용하였고 역전파 알고리즘을 통해 학습을 수행하였다. 인공신경망을 사용한 콘크리트 인장강도의 추정 결과 시험 결과와 추정결과가 유사하게 나타나는 것을 확인할 수 있었다. 인공신경망에서 결합력이 큰 변수들은 물-시멘트비와 섬유의 혼입량으로 나타났으며 섬유보강콘크리트의 인장강도는 물-시멘트비에 영향을 받는 압축강도와 혼입량을 통해 추정할 수 있을 것으로 판단된다.

• 대한족부족관절학회지
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• 제18권2호
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• pp.62-67
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• 2014

Purpose: Reconstructive surgeries for equinocavovarus foot deformities are quite variable, including hind-midfoot osteotomy or arthrodesis, soft tissue procedure, tendon transfers, etc. Comprehensive evaluation of the deformity and its etiology is mandatory for achievement of successful deformity correction. Few studies in this field have been reported. We report on the clinical and radiographic outcome of reconstruction for cavovarus foot deformities. Materials and Methods: The study is based on 16 feet with cavovarus foot deformities that underwent bony and soft tissue reconstructive surgery from 2004 to 2008. We evaluated the etiologies, varieties of surgical procedures performed, pain score, functional scores, and patient satisfaction and measured the radiographic parameters. Results: The average age at the time of surgery was 39.4 years old, with a male/female ratio of 9/4 and an average follow-up period of 23.9 months (range, 12~49 months). The etiologies of the cavovarus deformity were idiopathic 7 feet, residual poliomyelitis 5 feet, Charcot-Marie-Tooth disease 2 feet, and Guillain-Barre syndrome and hemiplegia due to cerebrovascular accident sequela 1 foot each. Lateral sliding calcaneal osteotomies were performed in 12 feet (75%), followed by Achilles tendon lengthening and plantar fascia release in 11 feet (69%), and first metatarsal dorsiflexion osteotomy/arthrodesis and tendon transfer in 10 feet (63%). Visual analogue scale pain score showed improvement, from an average of 4.2 to 0.5 points. American Orthopaedic Foot and Ankle Society ankle-hindfoot score showed significant improvement, from 47.8 to 90.0 points (p<0.05). All patients were satisfied. Ankle range of motion improved from $27.5^{\circ}$ to $46.7^{\circ}$. In radiographic measurements, calcaneal pitch angle improved from $19.1^{\circ}$ to $15.8^{\circ}$, Meary angle from $13.0^{\circ}$ to $9.3^{\circ}$, Hibb's angle from $44.3^{\circ}$ to $37.0^{\circ}$, and tibio-calcaneal axis angle from varus $17.5^{\circ}$ to varus $1.5^{\circ}$ Conclusion: We achieved successful correction of cavovarus foot deformities by performing appropriate comprehensive reconstructive procedures with improved functional, radiographic measures and high patient satisfaction.

• 한국임상수의학회지
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• 제30권1호
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• pp.57-60
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• 2013

개에서 포도중독에 의한 신부전 치료결과에 대한 임상적 분석을 위하여 205-2008년 기간 중 강원대학교 수의과대학 동물병원에 내원한 환자의 의료기록부를 분석하였다. 총 11두 (암컷 8두) 중 4두는 완전히 회복하였고, 3두는 폐사, 4두는 안락사로 처리되었다. 1두를 제외한 모든 환자는 포도를 섭취하였으나 정확한 섭취량은 알 수 없었다. 환자의 평균 연령은 5.3세 (범위 0.2-11.3세), 체중은 4.1 kg (범위 1.4-13 kg)였으며, 평균 입원기간은 7.1일 (범위 2-22일)로 나타났다. 모든 환자에서 구토와 식욕부진 증상을 보였으며, 일부 환자는 설사 (4두), 핍뇨 (5두), 무뇨 (4두) 소견을 보였다. 모든 환자에서 혈청 phosphorous, creatinine, BUN 농도가 증가된 소견을 보였으며, 고칼슘혈증 2두, 저칼슘혈증 2두, 나머지 7두는 정상소견이었다. 혈청 농도가 증가한 항목은 amylase 8두, ALP 7두, ALT 5두였으며, 혈액 가스 분석에서 8두는 대사성산증을 보였다. 경미하거나 중등도의 빈혈 소견이 5두에서 관찰되었으며, 회복한 환자와 비교할 때 폐사축의 경우 혈소판과 림프구 수가 상대적으로 낮았다.

• 한국수산과학회지
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• 제34권5호
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• pp.423-429
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• 2001

한국 연근해 보구치 자원의 지난 21년간 ($1975\~1995$년) 자원량을 이용하여 추정된 고유치는 밀도 독립적인 경우와 밀도 종속적인 경우 약 0.8 정도로 감소하는 추세에 있었으며, 밀도 종속적인 경우 상수 a는 $5.234\times10^{-10}$이였다. 그리고 보구치 자원의 연령별 출생율은 1세 1,053에서 6세 310,803의 범위였고, 연령별 생잔율은 1세 1,053 에서 6세 310,803의 범위였으며, 초기생잔율은 0.00005였다. 자원량 및 어획량 예측치는 추정된 매개변수를 사용하여 밀도독립적인 경우와 밀도 종속적인 경우의 Leslie Matrix에 적용해서 추정하였는데, 이때 어획사망계수가 $F_{35\%}$와 $F_{0.1}$, 수준인 0.252/yr와 0.368/yr에서 자원량과 어획량이 급격히 증가하였으며, 밀도 송속 적인 경우 밀도 효과의 부여는 환경수용력 (carrying capacity)을 산출하므로 보다 현실적으로 접근할 수 있다. 평형상태시의 어회 사망계수는 약 0.7/yr였다. 따라서, 본 연구는 현재 남획상태에 있는 한국 연근해 보구치 자원을 Leslie Matrix에 적용시켜 자원량 및 어획량 변동을 예측해 봄으로써 남획으로 인해 고갈되어 가는 보구치 자원을 회복시킬 관리방안을 제시하였다

• Nutrition Research and Practice
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• 제14권2호
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• pp.117-126
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• 2020

BACKGROUND/OBJECTIVES: Vitamin D and zinc are recognized for their roles in immune-modulation, and their deficiencies are suggested to be important risk factors for childhood infections. This study, therefore, undertook to assess the occurrence of infections in rural Indian schoolchildren, subsequent to daily supplementation with vitamin D-calcium or zinc for 6 months. SUBJECTS/METHODS: This was a randomized, double-blind, placebo-controlled trial in apparently healthy 6-12 year-old rural Indian children, recruited to 3 study arms: vitamin D arm (1,000 IU D3 - 500 mg calcium, n = 135), zinc arm (10 mg, n = 150) and placebo arm (n = 150). The infection status was assessed using a validated questionnaire, and the biochemical parameters of serum 25(OH)D and serum zinc were measured by ELISA and colorimetry, respectively. The primary outcome variable was occurrence of infections (upper respiratory and total infections). RESULTS: Serum 25(OH)D concentration in the vitamin D arm improved significantly by 34%, from 59.7 ± 10.9 nmol/L to 80 ± 23.3 nmol/L (P < 0.0001), but no improvement was observed for serum zinc concentration. While there was significant increase in the percentage of children reporting no or mild upper respiratory tract infections (URTI) and total infections (TI) in all three groups, improvements in the supplemented groups were similar to the placebo group. However, the vitamin D arm reported lower URTI and TI status in the vitamin D sufficient versus insufficient children. Also, URTI and TI status were found to be significantly (P < 0.0001) lower in children with improved 25(OH)D versus unchanged 25(OH)D. CONCLUSIONS: Vitamin D-calcium supplementation helped to improve the vitamin D status but exerts no effect on the occurrence of infections when compared to the placebo group. Improvement in the serum 25(OH)D concentrations and attainment of vitamin D sufficiency may exert a beneficial effect on the infection status and needs to be investigated further. To evaluate the efficacy of zinc supplementation, higher dosages need to be administered in future studies.

• Ocean and Polar Research
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• 제30권4호
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• pp.519-536
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• 2008

The relatively tranquil area within the Gogunsan Archipelago was for the first time investigated preliminarily with respect to modern sedimentological processes in association with the emplacement of the Saemangeum Dyke. Basic sedimentological observations, bathymetry and surface sediments were performed twice during 2006-2008 to compare the results and elaborate changes during that period of time. In addition, sediment dynamical observations were carried out with latest measuring equipment along two transects crossing the entrances of the archipelago, including 12-hour onboard measurements of current, suspended sediments, temperature, and salinity. This dataset was used to reveal hydrodynamic characteristics for spring season April-May and to estimate the direction and relative magnitude of the net flux of suspended sediments. There occurred three depositional areas (A to C) within the archipelago, where sediment texture was also changed. In area A, around Yami Island and the dyke, and area B, in the center of the archipelago, surface sediments became coarsened over the two-year period; sand content increased 5% at the expense of silt content in the former, whereas silt content increased 3% at the expense of clay content in the latter. By comparison, area C in the western entrance of the archipelago shows a textural trend of fining with more silt and clay (combined increase of 5%) at the expense of sand content. The accumulation of sediments in areas A and B is attributable to the sand and silt resuspended from the seabed sediments off sector 4 of the dyke during the winter. The origin of the fine materials depositing on area C is uncertain at present, although suspended sediments moving offshore around the archipelago may be one of the most likely candidates for the source. The temperature of seawater increased rapidly from $9-10^{\circ}C$ in April to $14-16^{\circ}C$ in May, whereas salinity remained more or less constant at 31-32%o during the two months. Both of these parameters showed little variations with depth through a tidal cycle, suggesting good mixing of seawater without any help of significant waves. The consistency of salinity during a tidal cycle also indicates no insignificant effects of freshwater from the rivers Mangyung and Donjin emitting through the opening gap near Sinsi Island. The suspended sediment concentrations were higher at the entrance between Sunyu and Sinsi islands than at the entrance between Hoenggyong and Sinsi islands, ranging from 20 and 30 mg/l and from 5 and 15 mg/l, respectively at the sea surface. Although tidal currents were variable across a transect between Sunyu and Sinsi islands, the currents across the entrance between Hoenggyong and Sinsi islands flowed consistently in the same direction all over the transect during a tidal cycle. The estimation of net flux of suspended sediments indicates that suspended sediments are transferred to the Gogunsan Archipelago mainly through a relatively deep trough adjacent to Sinsi Island toward the shallow area around Yami Island and the dyke.

• Journal of Preventive Medicine and Public Health
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• 제50권6호
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• pp.361-368
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• 2017

Objectives: This study aimed to explore dimensions in addition to the 5 dimensions of the 5-level EQ-5D version (EQ-5D-5L) that could satisfactorily explain variation in health-related quality of life (HRQoL) in the general population of South Korea. Methods: Domains related to HRQoL were searched through a review of existing HRQoL instruments. Among the 28 potential dimensions, the 5 dimensions of the EQ-5D-5L and 7 additional dimensions (vision, hearing, communication, cognitive function, social relationships, vitality, and sleep) were included. A representative sample of 600 subjects was selected for the survey, which was administered through face-to-face interviews. Subjects were asked to report problems in 12 health dimensions at 5 levels, as well as their self-rated health status using the EuroQol visual analogue scale (EQ-VAS) and a 5-point Likert scale. Among subjects who reported no problems for any of the parameters in the EQ-5D-5L, we analyzed the frequencies of problems in the additional dimensions. A linear regression model with the EQ-VAS as the dependent variable was performed to identify additional significant dimensions. Results: Among respondents who reported full health on the EQ-5D-5L (n=365), 32% reported a problem for at least 1 additional dimension, and 14% reported worse than moderate self-rated health. Regression analysis revealed a $R^2$ of 0.228 for the original EQ-5D-5L dimensions, 0.200 for the new dimensions, and 0.263 for the 12 dimensions together. Among the added dimensions, vitality and sleep were significantly associated with EQ-VAS scores. Conclusions: This study identified significant dimensions for assessing self-rated health among members of the general public, in addition to the 5 dimensions of the EQ-5D-5L. These dimensions could be considered for inclusion in a new preference-based instrument or for developing a country-specific HRQoL instrument.

• 에너지공학
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• 제26권2호
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• pp.80-92
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• 2017

본 연구는 1998년부터 2015년까지의 16개 시도별 경유수요량, 경유제품 판매가격(유통단계), 및 총 부가가치생산의 패널데이터를 이용하여, 패널GLS, 고정효과(Fixed Effect), 확률효과(Random Effect) 및 동적패널(Dynamic Panel) 모형을 통해 국내 경유수요함수를 추정하고, 이를 통해 가격탄력성과 소득탄력성을 추정하였다. 단기 가격탄력성은 -0.2146(패널GLS), -0.2886(고정효과), -0.2854(확률효과), -0.1905(동적패널)로 추정되었고, 단기 소득탄력성은 0.7379(패널GLS), 0.4119(고정효과), 0.7260(확률효과), 0.4166(동적패널)로 추정되었는데, 모두 비탄력적인 것으로 나타났다. 장기 가격탄력성과 장기 소득탄력성은 동적패널을 통해 추정하였고, 각각 -0.4784, 1.0461로 유의하게 나타났다. 경유 수요는 소득에 증감에 대해 단기적으로는 비탄력적이나, 장기적으로는 탄력적으로 나타나고 있다. 추가로 서울지역을 기준으로 지역변수를 더미변수(Dummy Variables)로 하여 각 지역의 경유수요로의 효과를 검정하였는데, 10개 지역에서 상대적으로 유의하게 추정되었다.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2011년도 정기 학술발표대회
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• pp.172-172
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• 2011

The interaction between land surface and atmosphere is essentially affected by hydrometeorological variables including soil moisture. Accurate estimation of soil moisture at spatial and temporal scales is crucial to better understand its roles to the weather systems. The KLDAS(Korea Land Data Assimilation System) is a regional, specifically Korea peninsula land surface information systems. As other prior land data assimilation systems, this can provide initial soil field information which can be used in atmospheric simulations. For this study, as an enabling high-resolution tool, weather research and forecasting(WRF-ARW) model is applied to produce precipitation data using GFS(Global Forecast System) with GFS embedded and KLDAS soil moisture information as initialization data. WRF-ARW generates precipitation data for a specific region using different parameters in physics options. The produced precipitation data will be employed for simulations of Hydrological Models such as HEC(Hydrologic Engineering Center) - HMS(Hydrologic Modeling System) as predefined input data for selected regional water responses. The purpose of this study is to show the impact of a hydrometeorological variable such as soil moisture in KLDAS on hydrological consequences in Korea peninsula. The study region, Chongmi River Basin, is located in the center of Korea Peninsular. This has 60.8Km river length and 17.01% slope. This region mostly consists of farming field however the chosen study area placed in mountainous area. The length of river basin perimeter is 185Km and the average width of river is 9.53 meter with 676 meter highest elevation in this region. We have four different observation locations : Sulsung, Taepyung, Samjook, and Sangkeug observatoriesn, This watershed is selected as a tentative research location and continuously studied for getting hydrological effects from land surface information. Simulations for a real regional storm case(June 17~ June 25, 2006) are executed. WRF-ARW for this case study used WSM6 as a micro physics, Kain-Fritcsch Scheme for cumulus scheme, and YSU scheme for planetary boundary layer. The results of WRF simulations generate excellent precipitation data in terms of peak precipitation and date, and the pattern of daily precipitation for four locations. For Sankeug observatory, WRF overestimated precipitation approximately 100 mm/day on July 17, 2006. Taepyung and Samjook display that WRF produced either with KLDAS or with GFS embedded initial soil moisture data higher precipitation amounts compared to observation. Results and discussions in detail on accuracy of prediction using formerly mentioned manners are going to be presented in 2011 Annual Conference of the Korean Society of Hazard Mitigation.

• 대한수학교육학회지:수학교육학연구
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• 제15권1호
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• pp.75-105
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• 2005

본 연구는 엑셀을 활용한 소그룹 모델링의 흐름과 학생과 엑셀의 상호작용이 모델링에 미치는 영향에 대한 이해를 바탕으로 추후 엑셀을 활용한 소그룹 모델링을 통한 수학 교수ㆍ 학습을 위한 기초적인 정보를 제공하는데 목적이 있다. 엑셀을 활용한 소그룹 모델링의 흐름을 알아보기 위해 학생들이 고려하는 양, 양들간 관계, 구성하는 모델을 바탕으로 모델링 주기를 살펴보았다 또한 학생과 엑셀의 상호작용이 모델링에 미치는 영향을 이해하기 위해 학생과 엑셀의 상호작용을 모델 형성, 모델 정교화, 모델을 통한 상황 해석ㆍ예측ㆍ통제 측면에서 분석하였다. 본 연구로부터 엑셀을 활용한 소그룹 모델링이 어떻게 이루어지는가와 학생-엑셀 상호작용 패턴에 대한 이해를 바탕으로 모델링 도구로서의 엑셀의 잠재력을 확인하고 학생들의 모델링 활동에 있어서의 강점과 취약점을 확인할 수 있었다. 또한 엑셀을 활용한 소그룹 모델링이 보다 효과적으로 이루어지기 위해 요구되는 교사 역할에 관한 시사점을 얻을 수 있었다.