This paper demonstrates reliability for an unmanned controlling excavator robot system under developing. A reliability testing method and testing devices were proposed using operation modes of excavators. Then, minimum MTBF of the system for a confidence level is demonstrated through results of the accelerated life test.

This study investegated the positive effect of the urban agriculture experience program on the mental health of the elderly by measuring the mental health indices of stress and depression. The research subjects included an experiment group of seniors over 65 years old who participated in the program for over six months and a control group of seniors, whom resided in the same city. Stress and depression were surveyed as mental health indices, and the physiological disparity was measured to clarify the disparity in the autonomic nervous system. The collected data were analyzed with t-test using the SPSS WIN 12.0. The results of the stress index analysis revealed that, in terms of communication, stress scores related to loneliness were statistically significantly lower for the experiment group than the control group. Also, in terms of health, the stress levels of the experiment group tended to be significantly lower than the control group. The depression index analysis showed the control group had a much higher level of depression than the experiment group with considerably significant disparity. The autonomic nervous system analysis revealed the stress index was significantly lower for the experiment group than the control group, and also, in terms of pulse diversity, the experiment group was within the range of normality, whereas the control group was exposed to the influence of chronic stress. The research results showed that urban agriculture activities applied to the elderly stabilizes the sympathetic nerve and activates the parasympathetic nerve to increase the resistance against stress.

No abstract

With the city of Seoul undergoing rapid urban development in the last decade, rooftop green projects have been expanding continuously with support that started from the city of Seoul. This research was conducted to analyze the current usage of roof gardens and stimulate development of new roof gardens. From rooftop gardens of three hotels selected in Seoul and Incheon, customer satisfaction and preferences were examined and this research intended to propose renovation plans for roof gardens. From the analysis of customer satisfaction, C Hotel and P Hotel that are located in the downtown area were found to have lower satisfaction regarding the number of plants and plant variety when they were compared with H Hotel in Incheon. Analysis of user preference revealed that an ideal green space would hold cultural, community events, provide space and opportunities for physical exercise, and serve any other multiple purposes. This research, which examined user satisfaction and preferences for hotel rooftop gardens, intends to provide an effective plan for the structure of rooftop gardens and suggest useful renovation ideas. Lastly, it is concluded that a green area that is not only beautifully decorated but serves multiple functions as a cultural, socializing and relaxing space is highly capable of stimulating the popularity and use of rooftop gardens.