유아의 기질은 선천적으로 타고나며 개인차가 있어 환경에 의해 변화가 가능하고, 유아의 사회성에 중요한 영향을 미치는 한 변인이라 할 수 있다. 또한, 인간의 발달 특성상 유아에게 있어서 부모의 역할 중 부모의 긍정적인 양육태도는 유아의 사회성 발달에 매우 중요한 영향을 끼치게 되는데 이는 유아기부터 성인기까지 일생동안 상당히 안정적으로 유지되는 속성을 보인다. 본 연구의 목적은 유아의 사회성 발달에 유아의 기질과 유아가 최초로 만나게 되는 부모의 양육태도가 어떠한 영향을 미치는지를 알아보고 유아의 사회성 발달에 대한 이해와 자녀 양육에 있어서 부모의 바람직한 양육태도를 갖추기 위한 기초자료를 제공하고, 유아교육현장에서 사회성 발달을 지원하기 위한 다양한 교육적 활동을 활성화할 필요성을 제언하고자 함에 있다.

The ship steering is a very important factor for safe operation. Recently, the ship is controlled in a space other than the wheelhouse through the wired controller. However, there has been a continuing need to improve the inconvenience of wired systems. In this study, a system to control the steering angle and throttle of ship by RF communication method was developed and applied to actual ship. Since the reliability is secured through the safety evaluation, the wireless steering system improves the convenience and economic efficiency of ship steering.

This study describes the effects of palm oil biodiesel (PD) blended with diesel on the combustion performance, emission characteristics and soot morphology in a 4-cylinder CRDI diesel engine. 5 kinds of fuels are used with blending as diesel/biodiesel volume ratio 0%, 10%, 20%, 30%, 100%. The engine is operated under idle speed, 750rpm and load conditions of the engine are 0 Nm and 40Nm. The Coefficient of Variation(COV) of Indicated Mean Effective Pressure(IMEP) shows that the engine operates very steadily in the idle state. But fuel consumption is increased. And Emission results show that the oxygen in biodiesel has a great influence on the production of exhaust emissions. The nitrogen oxides(NOx) is decreased because of high viscosity and low heating values of biodiesel at low blend ratio. But NOx and Carbon monoxide(CO) are increased above a certain blend ratio. Particulate matter(PM) and Hydrocarbons(HC) is decreased according to increase of blend ratio. The size of soot is decreased and the morphology of soot is developed to cluster with increasing blend ratio.

Nanoparticles of PbTe are prepared via chemical reaction of the equimolar aqueous solutions of Pb(CH3COO)2 and Te at 120°C. The size of the obtained particles is 100 nm after calcination in a hydrogen atmosphere. Dense specimens for the thermoelectric characterization are produced by spark plasma sintering of prepared powders at 400°C to 500°C under 80 MPa for 5 min. The relative densities of the prepared specimens reach approximately 97% and are identified as cubic based on X-ray diffraction analyses. The thermoelectric properties are evaluated between 100°C and 300°C via electrical conductivity, Seebeck coefficient, and thermal conductivity. Compared with PbTe ingot, the reduction of the thermal conductivities by more than 30% is verified via phonon scattering at the grain boundaries, which thus contributes to the increase in the figure of merit.

A cold-work tool steel powder is used to fabricate 3-dimensional objects by selective laser melting using a high-pressure gas atomization process. The spherical powder particles form continuous carbide networks among the austenite matrix and its decomposition products. The carbides comprise Nb-rich MC and Mo-rich M2C. In the SLM process, the process parameters such as the laser power (90 W), layer thickness (25 μm), and hatch spacing (80 μm) are kept fixed, while the scan speed is changed from 50 mm/s to 4000 mm/s. At a low scan speed of 50 mm/s, spherical cavities develop due to over melting, while they are substantially reduced on increasing the speed to 2000 mm/s. The carbide network spacing decreases with increasing speed. At an excessively high speed of 4000 mm/s, long and irregularly shaped cavities are developed due to incomplete melting. The influence of the scan pattern is examined, for which 1 × 1 mm2 blocks constituting a processing layer are irradiated in a random sequence. This island-type pattern exhibits the same effect as that of a low scan speed. Post processing of an object using hot isostatic pressing leads to a great reduction in the porosity but causes coarsening of the microstructure.

Purpose of this study is to investigate structural behavior of the rectangular hollow column with various transverse reinforcement details. Experimental variables are diameter, arrangement details and lateral spacing of cross tie. A total of 66 column specimens have been prepared and tested under axial compressive load. Test results showed that behaviors of column specimens were different depending on the cross tie details. Specimens with cross tie wrapping longitudinal steel and transverse steel have greater strength and ductility than specimens with cross tie wrapping the longitudinal steel.

This study investigates the seismic performance of new hollow reinforced concrete (RC) bridge piers with triangular reinforcement details. The developed triangular reinforcement details are economically feasible and rational, and facilitate shorter construction periods. We tested a model of new hollow RC bridge piers with triangular reinforcement details under a constant axial load and a quasi-static, cyclically reversed horizontal load. We used a computer program, Reinforced Concrete Analysis in Higher Evaluation System Technology (RCAHEST), for analysis of RC structures. The used numerical method gives a realistic prediction of seismic performance throughout the loading cycles for several hollow pier specimens investigated. As a result, developed triangular reinforcement details for material quantity reduction was equal to existing reinforcement details in terms of required performance.

본 시험은 열대지역적응 자포니카인 진미벼, IRKR 1 (IRRIRice and Korea Rice 1 약칭, 계통명은 IR 68333-R-R-B-22)및 인디카인 IR 64 품종에 대하여 필리핀인을 주요 대상으로쌀 외관 및 밥맛 선호도를 평가하여 개발된 품종의 농가 재배확대 및 새로운 품종개발의 기초자료로 이용하고자 수행하였다. 1. 쌀의 외관품질 선호도 평가에서 패널로 참여한 필리핀인은 투명도·외관 > 향·색깔 > 쌀의 길이·모양 순이었다. 한국인은 쌀의 길이·모양· 투명도 > 외관 > 색깔·향 순이었다. 따라서 필리핀인은 완전미율이 높고 향이 나는 쌀을, 한국인은 단원립이면서 완전미율이 높은 쌀을 선호하였다. 2. 식미관능평가 결과 필리핀인은 인디카 고아밀로스 품종인 IR 64보다 자포니카 중간아밀로스인 진미벼와 IRKR 1을선호하여 기존에 알려진 인디카를 선호한다는 선행 연구결과와는 상이하였다. 3. 따라서 패널로 참여한 필리핀인의 자포니카 쌀에 대한 선호도를 보다 정확하게 평가하기 위해 식미관능평가 5개 항목별 선호도를 분석한 결과, 밥의 모양, 냄새, 맛, 질감은 통계적차이가 없었다. 반면 찰기는 진미벼 보다는 IRKR 1을 선호하였다. 반면 한국인은 진미벼 보다 IRKR 1이 밥의 찰기가 적고 질감이 거칠면서 딱딱한 촉감으로 인해 진미벼를 선호한것으로 고찰된다. 4. 이상의 결과를 요약하면, 패널로 참여한 필리핀인이 선호하는 자포니카 쌀의 식미는 한국인이 선호하는 것 보다는 찰기가 적고, 질감은 좀 더 딱딱한 것으로 사료된다.

The purpose of this study is to investigate the behavior characteristics of new hollow reinforced concrete (RC) bridge pier sections with triangular reinforcement details and to provide the details and reference data. Among the numerous parameters, this study concentrates on the shape of the section, the reinforcement details and the spacing of the transverse reinforcement. Additional eight column section specimens were tested under quasi-static monotonic loading. In this study, the computer program, named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology), was used. A innovative confining effect model was adopted for new hollow bridge pier sections. This study documents the testing of new hollow RC bridge pier sections with triangular reinforcement details and presents conclusions based on the experimental and analytical findings.

The purpose of this study is to investigate the seismic behavior of hollow reinforced concrete bridge column systems with reinforcement details for material quantity reduction and to provide the details and reference data. Five hollow reinforced concrete bridge columns were tested under a constant axial load and a cyclically reversed horizontal load. The accuracy and objectivity of the assessment process can be enhanced by using a sophisticated nonlinear finite element analysis program. The adopted numerical method gives a realistic prediction of seismic performance throughout the loading cycles for several the investigated test specimens. This study documents the testing of hollow reinforced concrete bridge column systems with reinforcement details for material quantity reduction and presents conclusions based on the experimental and analytical findings.