PURPOSES : The purpose of this study is to establish design criteria for right-turning lanes by analyzing the relationship between the speed and geometry of right-turning lanes in urban areas. METHODS : A right-turn vehicle with a traffic island was surveyed for 32 geometries and 4,012 vehicles. Using multiple regression, we developed a running speed prediction model based on the running speed characteristics and geometry scale. RESULTS : According to the analysis of the running speed of the right-turning channel, the 85th speed was 34.5-38.3 km/h, depending on the right-turning lane radius, and 32.4-39.0 km/h, depending on the channel width group. Based on the multi-regression, the right-turning radius and the channel width variables were statistically significant because of the influencing factors of the road speed. Two independent variables were positive (+) coefficients. CONCLUSIONS : In this study, we investigated the running speed state on the right-turning channel and the factors that influenced the running speed. In addition, the relationship between the running speed and other factors was modeled through statistical analysis, and a running speed prediction model was established. It was observed that the driving speed increased as the geometry scale increased. Based on the derived running speed model, the maximum design criteria for limiting the speed of the conductive channelized right-turning lane in urban areas were established.

UO2 kernels, a key component of fuel elements for high temperature gas cooled reactors, have usually been prepared by sol-gel methods. Sol-gel processes have a number of advantages, such as simple processes and facilities, and higher sphericity and density. In this study, to produce 900 μm-sized UO2 particles using an external gelation process, contact length extension of the NH3 gas of the broth droplets pass and the improvement of the gelation device capable of spraying 14 MNH4OH solution are used to form 3,000 μm-sized liquid droplets. To produce high-sphericity and high-density UO2 particles, HMTA, which promotes the gelation reaction in the uranium broth solution, is added to diffuse ammonium ions from the outside of the gelation solution during the aging process and generate ammonium ions from the inside of the ADU gel particles. Sufficient gelation inside of ADU gel particles is achieved, and the density of the UO2 spheres that undergo the subsequent treatment is 10.78 g/cm3; the sphericity is analyzed and found to be 0.948, indicating good experimental results.

본 연구는 비파괴적 이미징 기법인 Micro-CT를 이용하여 시간에 따른 고구마의 내부 병변의 변화를 정량적으로 분석하였다. 현재 국내에서 고구마를 8 ~ 10월에 수확하여 다음 해 여름까지 저장하지만, 재배 혹은 수확 이후 저장 기간 중 표피썩음병을 비롯한 여러 병충해로 인하여 상품성이 떨어져 해마다 많은 고구마를 선별과정에서 폐기하고 있다. 하지만 지금까지 고구마 병변 여부 판단을 사람의 육안에 의존해왔기 때문에 고구마 내부의 병변의 크기 및 분포를 보다 정확하게 확인하는 방법이 필요하다. 따라서 본 연구에서 X-선 흡수량의 차이를 통하여 피사체 내부 구조를 확인할 수 있는 Micro-CT를 이용하여 고구마 내부의 3차원적 병변의 분포와 시간에 따른 병변의 부피 변화를 정량적으로 분석하고자 하였다. 저장 이후 표피썩음병 병변이 시작된 베니하루카 품종의 고구마 시료에 대해 일주일 간격으로 6주 동안 Micro-CT 이미징을 수행하였다. 고구마 내부의 병변에 대한 단면 이미지뿐만 아니라 3차원 병변의 영역을 추출하였고, 마지막 6주차에 고구마 시료의 병변 단면과 Micro-CT로 획득한 단면을 비교하였다. 또한 고구마 병변의 부피를 정량화하여 6주 동안 일반적인 저장 조건에 보관한 고구마 시료의 병변 증가 경향을 분석하였다. 비파괴적 Micro-CT 이미징을 통하여 지속적으로 고구마 내부의 병변의 3차원 분포를 시각화하고 이를 바탕으로 병변의 부피를 정량함으로써 향후 재배 및 저장 조건에 따른 병변의 발달 과정 연구에 있어 영상 및 정량 기법을 구축할 수 있었다.

PURPOSES : In this study, the installation of drowsy rest areas and accidents are analyzed. The factors that affected the accidents caused by drowsy drivers in rest areas are analyzed to improve the safety of rest areas. METHODS : By comparing and analyzing the installation status of the rest areas for drowsy drivers, the accident status were analyzed. The logistic regression model was used to analyze the factors that affect accidents in the drowsy rest area. RESULTS : Most rest areas were installed below the installation criteria. Several accidents occurred when the vehicle entered the drowsy rest area. These rest areas had a short entry ramp, and no safety facilities were installed. The logistic regression model showed that the risk of an accident is lowered when the deceleration lane is longer than 215 m. Additionally, the risk of an accident is lowered when the rest area is installed in the straight section or the curve section, wherein the curve radius is greater than 2 km. CONCLUSIONS : In this study, we evaluated the installation status of the rest areas for drowsy drivers by comparing installation elements. Most rest areas for drowsy drivers were installed at different lengths of the ramp. Some of these were installed on the slope or curved sections of the road. We analyzed the accident status and developed an accident modal using the logistic regression model to identify the factors that affect accidents. It will be necessary to analyze accidents in drowsy rest areas continuously to improve safety for drowsy drivers.

본 연구는 어린이집 원장의 감성리더십과 서번트리더십이 보육교사의 행복플로리시에 미치는 영향력을 알아보고자 하였다. 본 연구를 위해 충청남도 및 경기도 어린이집에 근무하는 보육교사 271명을 대상으로 설문 조사하고 그 결과를 분석하였다. 본 연구의 결과는 다음과 같다. 첫째, 원장의 감성리더십은 보육교사의 행복 플로리시에 영향을 미치는 것으로 나타났으며, 원장의 자기인식 및 자기관리능력은 전반적 행복플로리시를 제외한 모든 하위요인에 정적인 영향을 미치는 것으로 나타났다. 사회인식 및 관계관리능력도 성취요인을 제외한 모든 하위요인 에 정적인 영향을 미치는 것으로 나타났다. 둘째, 원장의 서번트리더십의 구인 중 청지기정신 및 공동체 형성은 긍정적 정서에만 영향을 미치는 것으로 나타났으며, 성장지원 및 리더십 공유는 교사의 행복플로리시 전체 요인에 긍정적 영향을 미치는 것으로 나타났다. 이러한 결과는 향후 보육교사의 잠재력 개발을 통한 성장과 발전을 위한 프로그램이나 교육의 내용을 구성하는데 유용한 자료가 될 것으로 기대한다.

본 연구는 부모-자녀 관련 코칭 연구의 동향을 조사하여, 연도별 경향과 연구대상, 연구대상자 수, 연구주제, 연구방법, 학위논문과 학술지 경향을 분석함으로써 향후 부모-자녀 코칭 연구에 대한 구체적인 연구방법과 주제 등 연구방향을 설정하는데 기초자료로 활용할 수 있도록 하는데 목적이 있다. 이를 위해 2005년부터 2019년까지 국내에서 발간된 학술지와 학위논문 중 부모-자녀 코칭 관련 논문 129편을 대상으로 분석하였으며, 연구결과는 다음과 같다. 첫째, 부모-자녀 코칭연구는 2009년 이후 관련 논문 편수가 매해 꾸준히 증가하는 경향을 보이며, 2016년(22편)에 가장 많았으며, 둘째, 연구대상자로 어머니만을 선정한 경우가 60편 (46.5%)으로 가장 많았으며, 연구대상자 수의 경우 50명 미만에서 부모가 84편으로 가장 높게 나타났다. 셋째, 코칭 연구의 대부분이 실험을 통한 효과검증을 한 연구로 129편 중 111편으로 나타났다. 넷째, 연구주제 경향은 코칭과 양육효능감 및 의사소통이 36편(28.0%)으로 가장 높게 나타났다. 다섯째, 연구방법의 경우 양적연구가 76편(58.9%)으로 가장 많았으며, 다음으로 프로그램개발 23편(17.8%)으로 나타났다. 마지막으로 학위논문의 경우 석사 논문이 65편, 박사 학위 논문이 14편으로 나타났다. 학술지의 경우 ‘코칭연구’가 9편으로 가장 많았다. 위 연구결과를 토대로 연구주제, 연구대상, 연구방법의 다양화에 대한 향후 연구방향을 제안하였다.

PURPOSES: The purpose of this study is to develop a traffic accident prediction model using statistical data, to analyze child traffic accidents in school zones. Furthermore, we analyze the factors affecting child traffic accidents, as obtained from the results of the developed model. METHODS : From the literature review, we obtained data for child traffic accidents and various variables relating to road geometry and traffic safety facilities in school zones. We used these variables and data to develop a child traffic accident analysis model. The model was then developed into three types using the Limdep 9.0 statistical tool. RESULTS: As a result of the overdispersion test, the Poisson regression model was applied to all types of models with an overdispersion coefficient of close to zero. The results of the model development are as follows. The main model (all scope of analysis) was for a kindergarten, considering a local roadway, the accessibility of the roadway, the number of unsignalized intersections, and the school zones in commercial area as variables that increase traffic accidents. Sub-model typeⅠ(only the roadway connected to the main entrance) was for a kindergarten, considering a local roadway, skid resistant pavement, no-parking signs, the number of unsignalized intersections, and the number of commercial facilities as variables that increase traffic accidents. The main model and sub-model type Ⅰ showed a reduction in accidents when using forward-type traffic signals. Sub-model typeⅡ(only the roadway not connected to the main entrance) shows that the local roadway is the variable that most increases the probability of traffic accidents. However, when the roadway and walkway are separated, the probability of traffic accidents decreases significantly, by up to 90%. CONCLUSIONS: The results of this study demonstrate the need to restructure the method used to improve school zones. Moreover, the effect of various traffic safety facilities was quantitatively analyzed.

Generally, ceramic tiles for building construction are manufactured by dry forming process using granular powders prepared by spray drying process after mixing and grinding of mineral raw materials. In recent years, as the demand for large ceramic tiles with natural texture has increased, the development of granule powders with high packing ratio and excellent flowability has become more important. In this study, ceramic tile granule powders are coated with hydrophobically treated silica nanoparticles. The effects of hydrophobic silica coating on the flowability of granule powders and the strength of the green body are investigated in detail. Silica nanoparticles are hydrophobically treated with GPTMS(3-glycidoxypropyl trimethoxy silane), which is an epoxy-based silane coupling agent. As the coating concentration increases, the angle of repose and the compressibility decrease. The tap density and flowability index increase after silica coating treatment. These results indicate that hydrophobic treatment can improve the flowability of the granular powder, and prevent cracking of green body at high pressure molding.

The blood preparation is important for management and classification. Because the work bench for sorting blood is not produced domestically, we have developed a work bench to classify blood through this study. Single coil system was developed to control cooling efficiency and temperature distribution. And evaporator and heater were used to reduce condensate discharge. This allow us to maintain a constant temperature and the condensation remainder below 1L. This study is expected to expand to other bio-equipment development.

The A182 steel is used in the steam pressure regulator of power plant valves. Since the part is operated under high temperature and high pressure conditions, it is necessary to study the machining characteristics. In this study, EDS analysis of the tool wear shape according to the cutting condition of A182 steel was performed. The A182 steel is identified as a steel belonging to the hardest cutting material and will be used to derive the optimum cutting condition.

Three-dimensional(3D) printing is a process for producing complex-shaped 3D objects by repeatedly stacking thin layers according to digital information designed in 3D structures. 3D printing can be classified based on the method and material of additive manufacturing process. Among the various 3D printing methods, digital light processing is an additive manufacturing technique which can fabricate complex 3D structures with high accuracy. Recently, there have been many efforts to use ceramic material for an additive manufacturing process. Generally, ceramic material shows low processability due to its high hardness and strength. The introduction of additive manufacturing techniques into the fabrication of ceramics will improve the low processability and enable the fabrication of complex shapes and parts. In this study, we synthesize silica composite material that can be applied to digital light processing. The rheological and photopolymeric properties of the synthesized silica composite are investigated in detail. 3D objects are also successfully produced using the silica composite and digital light processing.

보육교사의 상호작용은 영유아의 건강한 발달을 지원할 뿐만 아니라 아동학대와 안전에도 영향을 미쳐 보육의 질을 저하 시킬 수 있다. 이에 보육교사의 상호작용 역량을 높이기 위한 다각적 접근이 이루어지고 있으나 상호작용 역량은 쉽게 높여지고 있지 않아 새로운 접근이 필요한 시점이다. 본 연구에서는 예비보육교사에게 의사소통의 새로운 대안으로 코칭프로그램을 적용하고 코칭기법을 활용한 상호작용 역량을 높여 어린이집에 취업 후 교사로서 영유아와 코칭을 적용한 질 높은 상호작용을 할 수 있도록 하는데 목적이 있다. 연구의 대상은 졸업과 동시 보육교사 자격을 취득하게 될 아동복지학과 재학생 90명을 실험집단과 통제집단으로 나누어 실험집단에 12주간 2시간30분씩 코칭프로그램을 실시하고, 코칭스킬과 자기효능감 척도를 사용하여 사전, 사후검사를 통해 수집된 자료를 SPSS Win 21.0프로그램을 활용하여 분석하였다. 연구결과 첫째, 코칭프로그램이 예비보육교사의 코칭스킬에 영향을 미쳤는지를 살펴본 결과 실험집단이 통제집단과 비교할 때 유의미한 변화가 있는 것으로 나타났다. 둘째, 예비보육교사의 자기효능감에 영향을 미쳤는지를 살펴본 결과 실험집단이 통제집단과 비교할 때 유의미한 변화가 있는 것으로 나타났다. 이는 코칭프로그램이 예비보육교사의 코칭스킬과 자기효능감을 높이는데 기여했다는 것을 시사한다.

자기 이해가 높을수록 자신이 소속된 집단에서 원활하고 안정적인 대인관계를 영위할 수 있다. 본 연구는 대학생활과 졸업 후 취업해야하는 부담을 가지고 있는 대학생들을 대상으로 에니어그램 프로그램이 자기이해에 미치는 효과를 검증하려는 목적으로 진행되었다. 연구의 대상은 천안에 위치한 N대학교의 대학생 124명이며, 8주 동안 에니어그램 프로그램을 실시하였다. 또한 자기이해 척도를 사용하여 사전, 사후검사를 통해 수집된 자료는 SPSS Win 23.0을 활용하여 분석하였다. 연구결과는 다음과 같다. 첫째, 에니어그램 프로그램은 대학생의 자기이해에 유의미한 영향을 미치는 것으로 나타났으며, 사전· 사후 검사 결과 자기이해검사의 하위영역인 안정성, 목표 지향성, 역할인지, 자기수용, 자기주장에 유의미한 결과가 나타났다. 둘째, 대학생의 자기이해 효과를 힘의 중심별로 분석한 결과 힘의 중심별 머리형, 가슴형, 배형에서 공통적으로 드러난 변화는 어떤 상황에서도 일관적이고 동질적으로 자기를 인식하는 안정성과 자기수용으로 나타났다. 이는 본 연구가 자기이해를 높이는데 기여했다는 것을 알 수 있다.

PURPOSES: In this study, design elements of rest areas for drowsy drivers are classified and appropriate criteria for each design element are presented. METHODS : By comparing and analyzing the design criteria for rest areas, the most appropriate installation criteria were suggested by considering the driving patterns of rest area users. RESULTS: As a result of the study, elements influencing the design of rest areas for drowsy drivers are suggested such as installation location and installation type. In addition, proper separation distance between resting areas was suggested considering vehicle flow, users’fatigue and physiological needs. Other criteria for rest areas were also suggested. CONCLUSIONS : Proper safety facilities were not installed in rest areas because appropriate criteria were not established. In this study, design elements were derived and installation criteria were designed so that rest areas could be used safely and conveniently.

In the sewer pipes, reinforced concrete pipes and concrete pipes are mostly used. However, it is difficult to ensure the long-term durability of the pipe due to the corrosion of the rebar which is used for the reinforcement of the concrete. Also, reinforced concrete pipes are difficult to secure watertightness due to deterioration and corrosion by hydrogen sulfide. In order to solve such problems, research on using sewer pipes made of plastic materials is being actively conducted. When soil pressure and live load act on the buried flexible pipe, the load acting on the pipe is transferred to the surrounding soil. So, the flexible pipe will support the load with the surrounding soil together. It is difficult to predict these behaviors theoretically and clearly. Therefore, the design equation for the buried flexible pipe is analyzed by adopting theoretically idealized assumptions and it is estimated through experimental studies that it is similar to the actual structural behavior. In this paper, the mechanical properties of the soil and the polyethylene pipe were considered in application of the method proposed in ASTM D 2412 to design the buried polyethylene pipe. Also, structural behavior of the pipe resisting external loads such as soil pressure was investigated to use a polyethylene pipe as the buried pipe and the long-term behavior of the polyethylene pipe was predicted by the compaction rate of surrounding backfill soil through the field test.

Various seismic isolation methods are being applied to bridges and buildings to improve their seismic performance. Most seismic isolation systems are the structural seismic isolation systems. In this study, the seismic performance of geotechnical seismic isolation system capable of isolating the lower foundation of the bridge structure from ground was evaluated. The geotechnical seismic isolation system was built with teflon, and the model structure was made by adopting the similitude law. The response acceleration for sinusoidal waves of various amplitudes and frequencies and seismic waves were analyzed by performing 1-G shaking table experiments. Fixed foundation, Sliding foundation, and Rocking foundation were evaluated. The results of this study indicated that the Teflon-type seismic foundation isolation system is effective in reducing the acceleration transmitted to the superstructure subject to large input ground motion. Response spectrum of the Rocking and Sliding foundation structures moves to the long period, while that of Fixed foundation moves to short period.