• 스마트미디어저널
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• 제13권3호
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• pp.62-73
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• 2024

This research, conducted over a three-year period starting from 2020, was a collaborative project between practitioners in the field of VE design and the Korea Expressway Corporation, aimed at innovating the design VE project to construct an intelligent ICT-based smart highway and enhancing highway driving performance and customer satisfaction. The research included R&D support for payment and management systems integrated with IOT technology, the application of the developed prototype at highway sites, and analysis of user performance evaluation. Based on the Innovation Work Roadmap of the Korea Expressway Corporation, the research process involved collaboration between a public participation group and an expert group, considering the technical feasibility of data-based ICT technology through the National Idea VE Contest. The final VE design results were implemented at the Seongnam tollgate site with budget support from relevant departments, followed by a satisfaction survey. It is expected that the continuous contributions to achieving an ESG society, such as the increase in the number of customers using the tolling zone equipped with smart upgrades, along with their satisfaction rate, and the reduction in carbon emissions and total settlement time of highway users, will be sustained.

• Steel and Composite Structures
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• 제50권2호
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• pp.159-181
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• 2024

In the present study, the effect of geometrical parameters of two different types of aluminum thin-walled structures on energy absorption under three-bending impact loading has been investigated experimentally and numerically. To evaluate the effect of parameters on the specific energy absorption (SEA), initial peak crushing force (IPCF), and the maximum crushing distance (δ), a design of experiment technique (DOE) with response surface method (RSM) was applied. Four different thin-walled structures have been tested under the low-velocity impact, and then they have simulated by ABAQUS software. An acceptable consistency between the numerical and experimental results was obtained. In this study, statistical analysis has been performed on various parameters of three different types of tubes. In the first and the second statistical analysis, the dimensional parameters of the cross-section, the number of holes, and the dimensional parameter of holes were considered as the design variables. The diameter reduction rate and the number of sections with different diameters are related to the third statistical analysis. All design points of the statistical method have been simulated by the finite element package, ABAQUS/Explicit. The final result shows that the height and thickness of tubes were more effective than other geometrical parameters, and despite the fact that the deformations of the cylindrical tubes were around forty percent greater than the rectangular tubes, the top desirability was relevant to the cylindrical tubes with reduced cross-sections.

• Design & Manufacturing
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• 제12권1호
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• pp.52-57
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• 2018

With the recent strengthening of environmental regulations and the need for cost reduction, excavators, a type of construction equipment, are being miniaturized while components are being developed in consideration of stability. In the case of excavator press parts, mainly high-strength steel sheets are being used to enhance stability and reduce weight. However, in the case of high-strength materials, there is a need to research product forming methods to reduce Springback in defects arising in parts assembly due to Springback that result from the internal residual stress that occurs in press forming being released after product forming. Accordingly, regarding the tank cover, an excavator press-forming part, this study selected a method to reduce distortion through analysis of the Springback occurrence rate and Springback causes through a forming analysis. A forming analysis was conducted for the Springback of the tank cover. Deformations of 13.714 mm in the upper part and 6.244 mm in the inner part of the product occurred, while wrinkles occurred on the sides of the product due to uneven thickness. A forming analysis was conducted for the major shapes of the product to investigate the causes of Springback. Distortion deformation due to the bead in the center of the product was confirmed to be a large factor. A Springback reduction method of correcting uneven thickness in the product sides, a Springback reduction method of removing the bead, and a correction method of restriking after the final forming were used in a forming analysis to determine the degree of Springback reduction. For the forming method to correct uneven thickness in the sides, deformation was reduced by 12% in the upper side compared to the existing model, but deformation in the inner side increased by 1%. For the restriking forming method, deformation decreased by 25% in the upper side and 13% in the inner side. For the bead removal method, deformation decreased by 28% in the upper side and 13% in the inner side, the largest Springback correction results. This indicates that the bead has a large affect on Springback.

• 보건행정학회지
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• 제24권2호
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• pp.120-127
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• 2014

Background: Since December 2010, online computerized prospective drug utilization review (pDUR) has been implemented in Korea. pDUR involves the review of each prescription before the medication is dispensed to the individual patient. The pDUR is performed electronically by Health Insurance Review & Assessment Service (HIRA), which is a Korean governmental agency, and then HIRA provides medical institutions and pharmacies with information that can be helpful to them in preventing potential drug problems such as drug/drug interactions or ingredient duplication. The aim of this study was to assess the impact of the Korean pDUR implementation on the proportion of drug-drug interactions (DDIs) using claims data from HIRA. Methods: A before-after comparison of the prevalence of DDIs between prescription was conducted, using HIRA administrative claims data of medical institution from January 2010 to December 2011. The analysis unit was the prescription issued and pairs before and after. The main outcome measures were the proportion of DDIs within- (control group) or between- physician encounters. To examine the difference, a paired t-test was applied. Results: We found that DDIs proportion between prescription decreased significantly (t=3.04, p=0.0026) after the implementation of pDUR, whereas there is no significant reduction within prescription (t=1.15, p=0.2518). With respect to the prevalence of DDIs between drug groups, the most dramatic reduction was occurred between 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors and anti-fungal agents. Conclusion: It seems effective that giving a direct feedback to prescribers by a prospective DUR. Further research is needed to assess the impact of DUR to final outcomes such as hospitalization.

• Asian-Australasian Journal of Animal Sciences
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• 제19권9호
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• pp.1314-1321
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• 2006

The objective of this work was to study the effect of mixed culture solid substrate fermentation of C. tropicalis ZD-3 with A. niger ZD-8 on detoxification of cottonseed meal (CSM), and to investigate the effect of fermentation period, proportion of CSM in substrate, sodium carbonate, minerals and heat treatment on the reduction of free gossypol levels during mixed culture solid substrate fermentation of CSM. Experiment 1: Three groups of disinfected CSM substrate were incubated for 48 h after inoculation with either of the fungi C. tropicalis ZD-3, A. niger ZD-8 or mixed culture (C. tropicalis ZD-3 with A. niger ZD-8). One non-inoculated group was used as the control. Levels of initial and final free gossypol (FG), CP and in vitro CP digestibility were assayed. The results indicated that mixed culture fermentation was far more effective than single strain fermentation, which not only had higher detoxification rate, but also had higher CP content and in vitro digestibility. Experiment 2: CSM substrates were treated according to experimental variables including fermentation period, proportion of CSM in substrate, sodium carbonate, minerals and heat treatment, Then, the treated CSM substrates were inoculated with mixed culture (C. tropicalis ZD-3 with A. niger ZD-8) and incubated at $30^{\circ}C$ for 36 h in a 95% relative humidity chamber. After fermentation ended, FG and CP content of fermented CSM substrate was assayed. The results showed that the appropriate fermentation period was 36 h, and the optimal proportion of CSM in substrate was 70%. Addition of sodium carbonate to CSM substrate was beneficial for fermentative detoxification. Heat treatment could facilitate fermentative detoxification, and supplementation with minerals was instrumental in reducing gossypol levels during mixed culture solid substrate fermentation of CSM.

• 한국세라믹학회지
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• 제40권8호
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• pp.784-790
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• 2003

본 논문은 세라믹재료가 강화재로써 보강된 복합재료가 횡방향의 단축인장하중을 받는 경우, 복합재료의 변형, 재료내 발생되는 손상의 특징, 및 응력-변형률 특성에 관한 컴퓨터 해석결과이다. 해석은 SiC/Ti 시스템을 대상으로 하였으며, 특성은 강화재의 배열형태, 강화재/기지 계면에서의 결합유무, 강화재의 부피분율변화에 대하여 각기 해석되었다. 계면에서 강한 결합이 있는 복합재와는 달리, 약한 결합의 복합재는 인장하중에 의하여 세라믹/기지 계면에서 분리가 발생되었다. 이 분리는 전체 복합재의 강성을 감소시키며, 세라믹 강화재의 부피분율이 증가할수록 탄성계수 및 횡방향 평균응력의 최종크기를 나타내는 한계응력의 크기감소로 나타났다. 계면결합이 강한 경우는 세라믹 부피분율이 증가할수록 사각형 배열보다는 육각형배열의 복합재에서 다소 큰 증가율로 나타났다. 그러나, 계면결합이 약한 경우는 세라믹 부피분율이 증가할수록 사각형 배열보다는 육각형배열의 복합재에서 상대적으로 큰 감소율로 해석되었다. 본 연구의 해석결과는 알려진 문헌의 결과와 잘 일치하였다.

• 한국양식학회지
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• 제11권1호
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• pp.39-48
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• 1998

Growth performance and excretions of nitrogen (N) and phosphorus (P) were investigated with carp (Cyprinus carpio) with carp (Cyprinus carpio) grower fed a low pollution diets (A and B) and commercial ones (Com-1 and Com-2). A recirculated rearing system (Exp. I) and a floating net cage system (Exp. II) were employed for two feeding trials in which fish having an initial body weight of 152g and 193g were fed for 41 an 39 days, respectively. The highest weight gain, daily growth rate and protein efficiency ratio were found (P<0.05) in fish fed diet A containing 10% fish meal and 2% monocalcium phosphate (MCP) for both experiments. They also showed the lowest feed conversion ratio and daily feeding ration among treatments. Fish fed diet B containing 10% fish meal, 5% fish protein concentrate and 1% MCP showed weight gain and FCR more improved (P<0.05) than those fed commercial diets. In all groups, whole body cmpositions were not greatly different among treatment, and protein and P contents in final fish ranged from 14.3 to 15.6% and from 0.39 to 0.48%, respectively. Fish fed diet A excreted the least N which were 38.3 in Exp. I and 39.6g/kg gain in Exp. II. However, the values found in fish fed two commercial diets amounted to 59.1 and 58.9g, respectively. A significant decrease in P excretion was also found in fish groups fed diets A and B. In Exp. I, a reduction of 53.4% was shown in fish fed diet A, compared to the averaged value (18.5g P/kg gain) of two commercial groups. In Exp. II conducted using the floating net cages, fish fed diet B excreted the least P (8.6g/kg gain) among the treatment, which was followed by fish fed diet A, showing 48.6% reduction compared to the average value (18.5g/kg gain) for fish fed two commercial diets. The present results clearly showed that N and P excretions from fish culture could be significantly reduced by using the low pollution diet.

• 한국작물학회지
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• 제30권1호
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• pp.39-46
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• 1985

추파 대·소맥의 조숙품종의 조기출수에 따른 개화등숙 및 수량성 변화를 구명하고자 대맥품종 조강보리, 밀양6호, 올보리, 동보리 1호 및 부농과 소맥품종 수원210호, 올밀, 조광 및 농림16호 등을 공시포장조건에서 파종기 차이와 장일처리로써 조기출수 및 출수기 차이를 유도하여 본 실험을 수행하여 얻은 결과를 요약하면 다음과 같다. 1. 파종기 및 장일처리에 의해 대·소맥에서 15일 출수기 차이가 유도되었으나, 성숙기는 불과 2∼6밖에 촉진되지 않았다. 2. 조기출수한 경우 출수∼개화 일수 및 등숙일수가 연장되었으며, 출수∼개화 일수 연장이 더 큰 것으로 나타났고, 이들 기간과 평균기온 간에는 각각 고도의 부상관이 있었다. 3. 조기출수만 것일수록 등숙초기의 엽면적은 좁았고, 엽면적유지기간(Leaf area duration)은 컸으며, 순동화율(NAR)은 낮았다. 4. 조기출수한 것에서 천립중은 증가하였으나 종실수량은 현저히 감소하였는데 이는 주로 수수 및 일수입수의 감소에 기인하는 것으로 나타났다.

• 한국콘텐츠학회논문지
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• 제14권9호
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• pp.102-109
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• 2014

HEVC의 화면내 예측 부호화는 예측 모드를 기존 H.264/AVC에 비해서 최대 35개까지 확장함으로써 향상된 부호화 효율을 갖는다. 반면 화면내 부호화의 복잡도 또한 크게 증가하여 복잡도 감소를 위한 고속 부호화 기법이 요구된다. 본 논문에서는 HEVC의 참조모델인 HM에 화면내 고속 부호화를 위하여 채택된 RMD(Rough Mode Decision)에 추가적으로 복잡도 감소를 위하여 고속 화면내 예측 모드 결정 기법을 제시한다. 본 기법은 후보 모드를 결정하기 위한 RMD 과정에서의 탐색 모드 수와 선택된 후보 모드로부터 최종 모드를 결정하기 위한 탐색 모드 수를 제한하는 방법을 결합하여 모드 결정을 위한 복잡도를 감소한다. 본 제안 기법은 실험결과 HM 12.0에서 다양한 테스트시퀀스에서 HM 대비 1.0%의 비트 증가로 13.2%의 복잡도를 감소시킬 수 있었다.

• 방사성폐기물학회지
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• 제10권4호
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• pp.247-254
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• 2012

원전에서 발생되는 방사성폐기물에 대한 고화처리 방법 중 하나인 유리화기술이 일부 가연성폐기물에 대해 적용되고 있다. 국내외적으로 중저준위 방사성폐기물의 효과적인 감용과 안정적인 처분을 위해 다양한 폐기물에 대한 유리화기술 적용방안이 확대 연구되고 있으며, 최근에는 가연성폐기물 뿐만 아니라 알루미늄 금속과 같은 비가연성폐기물에도 유리화 연구가 활발하게 진행되고 있다. 공기조화계통 (HVAC)에는 주로 필터가 이용되고 있으며, 사용 후 필터는 여과재 (유리섬유 및 알루미늄)를 이용하여 배기체를 흡착하기 때문에 방사성폐기물로 처리가 되어야 한다. 본 연구는 필터에 대한 처리기술 연구를 위해 유도가열식 저온용융로 (Cold Crucible Induction Melter: CCIM)를 이용한 유리화 타당성 연구를 수행하였다. 사용후 필터에 대한 유리화 (Vitrification)는 먼저 유리섬유 및 알루미늄 함량을 고려한 최적의 유리조성을 개발 하였으며, 개발된 유리 조성을 이용하여 최적의 폐기물 저감을 위한 용융변수와 최종 생성된 유리고화체의 특성을 분석하였다. 사용후 필터 유리화용 조성유리는 주로 $SiO_2$와 $B_2O_3$로 구성되어 있다. 전기로를 이용한 용융물 특성시험에서는 폐기물 투입률 및 최종 생성물인 유리고화체의 특성이 검토되었다. 본 연구에서는 알루미늄 금속과 유리섬유로 구성된 필터에 대한 유리조성 개발과 이를 통해 생성된 유리고화체의 물리화학적 특성을 검토하고 유리화 타당성을 확인하였다.