Max-plus algebra is a nonlinear system made of two operations, maximization (max) and additions (plus), that are corresponding to the addition and multiplication in the traditional algebra, in respect. This algebraic method can be applied to many types of discrete event systems showing the state transition with the maximization and addition operations. Robotic cell with predetermined cyclic schedule is one of such systems. We consider a robotic cell that consists of a single robot and several isolated processing modules. We discuss steady state analysis of such robot cell when all the parts have the processing order as a flow shop. To model timing behavior of a robotic cell, we develop a max-plus algebraic system. Given a particular robot transfer sequence, we prove the unique existence of the stationary cyclic behavior and identify the schedule. Furthermore we suggest max-plus algebraic way to develop a robust schedule which endures the outside processing variability. Finally, a monitoring and control system for such robotic cell based on the max-plus algebraic model is also proposed.

The analysis of the written verdicts in recent five years was conducted to obtain preventive measures of collision between fishing vessel and non fishing vessel. As a result, a collision much happened in offshore trap for fishing vessel and below 5,000 tons of small and medium class for non fishing vessel. A person involved in a marine accident occupied 68% in sixth class deck officer and small boat operator for fishing vessel and 29% in third class deck officer for non fishing vessel. 90% of the collision happened in a underway by operating state and 84% in sight of one another by visibility state. The systemic radar training was required since 47% of the collisions was occurred on the condition of radar operation in fishing vessel. The main cause of poor lookout was a intensive fishing and poor lookout on movement by radar for fishing vessel and one man watch system and no recognition of one another by radar for non fishing vessel. This result is expected to contribute for the decrease of collision.

The purpose of this paper is to examine the effects on reliability of equipment or product which spends a great deal of its time in the non-operating condition. The paper will look at the effects on the failure modes, the failure rates, the failure distribution and the possible reliability models. Many military and commercial systems experienced periods of non-operating stage throughout their life cycle, such as periods of operational storage where the system waits, ready for use. The design of such systems must account for how these periods of non-operating effects system performance. The simulation methodology for reliability analysis was developed to support the evaluation of nonoperating modes of operation of systems and subsystems. For proper handling of the non-operating environment, issues relating to non-operating failures need to be taken into consideration from design stage of the life cycle. Furthermore, the relevant environmental concerns and issues that need to be taken into consideration are discussed.

This paper is a case study of reliability assessment with field warranty data of Clutch Master Cylinder(CMC) in hydraulic clutch system. We estimate lifetime distribution using field warranty data which contain much useful information for understanding reliability of the system in the real-world environments. However, the estimated parameters are far from existing reference values, which seems to be caused right censored field warranty data. To modify the parameters, we use the information of the durability test which is performed to verify that the lifetime of the item meets the required level. After that, we can observe that the modified parameters are closer to the existing reference values. This case study shows a possible idea to supplement lack of right censored field warranty data and its applicability

The purpose of this study was to provide a practical guide to the proper way of lifting a patient using various types of stretcher that rescue crews use by analyzing the load on the lumbar region. The experiment was conducted with working male and female rescue crews. Having mixed groups of gender complete tasks such as lifting, moving, and unloading a patient using four different types of stretcher, we recorded variations of the lumbar bending angle and calculated the load on the lumbar region using 3D SSPP. The data showed, in terms of the lumbar bending angle, it was greater when only females were involved in the work, and there were very significant differences in the angle depending on the types of stretcher used and body sizes of each subject. In the analysis of the load on the lumbar based on the bending angle, NIOSH was over the recommended limit in certain groups. Utilizing the analysis, it is recommended, in the medium and long term, to improve equipments for rescue personnel and to guide them to the proper way of working.

The purpose of this study was to provide a practical guide to the use of various stretchers that rescue workers use by analyzing muscle fatigue degree associated with lifting a patient. The experiment was conducted with working male and female rescue crews. Having mixed groups of gender complete tasks such as lifting, moving, and unloading a patient using four different types of stretcher, we recorded each muscle fatigue degree in the shoulder and lower back regions of each subject. The data showed, in terms of muscle activity, differences within each group of genders and its combinations were significant in certain muscle groups depending on the types of stretcher used and body sizes of each subject, and, when it comes to Elerctor Spenae, the female subjects used more muscular strength than the males did. In regards to the muscle fatigue degree, there was no significant difference found within each group of the genders, body sizes, and their combinations. However, in the case of applying different models of stretcher, there were significantly differences in the fatigue degree.

The purpose of this study is to evaluate IPA(Importance Performance Analysis) of the factors that influence University Student's Satisfaction of teaching. The sample was selected 173 students in I university. We will conduct the IPA to compare importance and satisfaction about the factors and analyze by frequency analysis, paired t-test, ANOVA using the SPSS 19.

한문에서 多義語의 의미항목 분별은 각 개념의미의 차이와 문맥을 통해 드러나 는 용법의에 대한 이해를 통해 정확한 독해를 이끌어 낸다는 점에서 중요한 학습 요소라 할 수 있다. 본고에서 2007개정 교육과정에 의해 집필된 고등학교 한문Ⅰ 5종 교과서를 검토해 본 바에 의하면, 모두 다의어를 중시하여 이를 학습 요소로 제시하고 있지만 다의어 한자 선정이 수의적인 경향이 있으며 다의어의 의미 항 목 용례로 제시된 것이 대부분 ‘언어생활 한자 어휘’여서 한문독해력 신장과는 일 정한 거리가 있었다. 이러한 실태의 주요 원인은 다의어 한자 선정에 대한 일정한 기준의 부재라고 할 수 있다. 이에 본고에서는 몇 가지 방안을 제시하였는데 1) 異音異詞의 경우 2) 동일한 한자가 실사, 허사를 모두 표기하는 경우 3) 의미의 유연성이 희박한 경우 4) 빈도수가 높은 경우 등이다. 본고에서는 이를 근거로 하 여 한문 교육용 기초한자 1800자 내에서 다의어 한자를 선정하여 그 목록을 제시하고 다의어의 분별된 의미항목에 따른 한문 용례도 제시하였다.