This paper introduces the new concept of a gripper mechanism mounted on the home cleaning robot. This new mechanism composed of two grippers and an auxiliary dustpan can tidy and load up objects. We additionally analyze the required motor torque and dynamic motion of this robot using dynamic simulation of Recurdyn. This new tidying gripper mechanism is expected to be used in various home cleaning applications.

자갈 궤도는 부설 후 궤도틀림이 발생하여 지속적인 유지·보수 작업이 필요하다. 이를 개선하기 위하여 기존의 자갈 궤도 에 급속경화 모르타르를 주입하여 단시간 내에 콘크리트 궤도로 치환할 수 있는 급속경화궤도가 개발되었다. 교량에 부설되 는 급속경화궤도는 교량과 궤도의 거동을 일치시키기 위하여 후설치 앵커를 궤도 세그먼트 중앙부에 시공한다. 본 논문은 앵커로 교량과 연결된 급속경화궤도와 교량의 궤도-교량 상호작용 해석을 수행하여 레일 및 앵커의 안전성을 검토하였다. 이때 앵커의 강성 및 강도, 급속경화 콘크리트의 재령, 급속경화궤도와 교량 사이의 마찰을 고려하였다. 이를 바탕으로 급속 경화궤도 부설 후 적절한 앵커의 설치시기 및 열차 정상운행 가능시기를 검토하였다.

Recently, functionalization of construction materials using nano materials is being studied in domestic and overseas. In this study, functionalization of cement composites using excellent mechanical characteristics, electrical and thermal conductivity characteristics was carried out. The basic study on the heat characteristics of cement mortar containing Single-walled Carbon Nano Tube(SWCNT), one of the CNT types, has been carried out and this study is aimed to verify whether heat characteristics is effective at low content mixing. The experimental parameters were selected as CNT content, curing age, and supplied voltage. The size of specimens was 50 x 50 x 50mm3 and three specimens were fabricated. As a result, heat characteristics of the SWCNT cement mortar was confirmed even at a low CNT content. As the curing progressed, it was confirmed that heat generation effect was low. But it was confirmed that the heat characteristics were sufficiently exhibited when 100V or more voltage was supplied.

This study presents the stone cutter design that can rotate and change the cutting side of the stone automatically by the combination structures of the rotatable and foldable plates. Foldable plates are consisted with the iron plate and the hydraulic cylinders system(1500W pump power) which can generate high pressure to raise the plates and the stone. Additionally, rotatable plates are designed by gear system which has high gear ratio(1:8) for rotating heavy stone(5ton) easily. We analyzed the movement of the stone and investigated the total system of the stone cutter including a rotator and a tilter. Moreover, we constructed a control board to control the system accurately. This system can induce high quality cutting process controlled within errors of 5% and also reduce the process time from about 20 min to 90 sec by the automatic system.

This study measured the particulate matter (PM) in a subway tunnel using a dust spectrometer and estimated the PM10 and PM2.5 using a Kriging method. For the hourly measurement, a probe was attached inside the cabin and put through the window to collect data from the outside. The Kriging method is a spatial analysis method, and time and spatial data were applied in the subway tunnel along with a PM concentration map. The result of the measurement shows that PM10 is 31.9~271.3 μg/m3 and PM2.5 is 30.9~209.5 μg/m3. In addition, The pollutant map shows that some sections have a higher concentration than other sections because of the depth and curvature of tunnel and traffic volume on the section and local construction. Also, the results show that differences concentration at different times of sampling could be distinguished. The highest concentration was found at 3 pm while the lowest was at 12 pm. We expect to use the pollutant map in planning air quality improvements for the tunnel.

Recently, researches of concrete performance improvement are increased in the advanced countries. Most nano material research is analyzed by experiment. This study performs a numerical analysis used by tensile strength of MWCNT and nano continuum theory, so effect on the performance improvements of nano mortar is analytically confirmed. Preceding researches about experimental result of flexural strength by Chan and Andrawes are comparative verified with result of multi-scale finite element modeling. In addition, parametric studies were conducted to investigate the effect of the ratio of width and the ratio of height on the behavior of proposed finite element modeling by nonlinear finite element analyses.