신제품 개발에 있어서 제품의 잠재적 고장모드를 줄이기 위한 설계 노력은 매우 중요하며 이를 위해서는 체계적이고 혁신적인 신뢰성프로그램을 적용하는 것이 반드시 필요하다. 기업에서 동시공학을 기초로 한 건전한 신뢰성프로그램에 포함된 주요활동으로는 DFR(Design for Reliability), 신뢰성검증 및 물리적 해석활동 등이 있으며, 이 중 DFR은 제품 개발을 지원하는 첫 번째 과학적 신뢰성활동이다. 본 연구는 브레이크패드의 신뢰성을 향상시키기 위

Blake, Yeats, and Bishop wrote poetry about children from a child’s perspective, to make us take a closer look at our behaviors, thoughts, and society. Both Yeats’s “The Stolen Child” and Blake’s “The Chimney Sweeper” in Songs of Innocence juxtapose two different worlds, and the child in each poem is associated with the ideal world of our dream. For Blake, the other world as opposed to this world is characterized by perfection filled with love and compassion, which only God can create. Yeats’s “The Stolen Child,” on the other hand, is not characterized by good versus evil; the world we inhabit, though full of sufferings, has traces of beauty that God has given to humanity. Yeats makes us reminisce about our childhood when we were innocent, suggesting that the key to happiness in our daily lives can be found there. Bishop furthers the device of childhood reminiscence with an emphasis on human perceptions, making a psychological approach to her poems, “The First Death in Nova Scotia,” “Sestina,” and “Manners”; hence, the perspective of her child speaker is much more complicated so as to reveal human conditions. We have to find out what the actual world looks like in the poem by inferring what the child gives. Because the psychology of the child is not explained by anyone else in the poem, we place ourselves in child’s perspective and compare the experiences from an adult’s point of view. All the poems about children discussed in this paper are really about adults.

  Mahalanobis Taguchi-System (MTS) is a pattern information technology, which has been used in different diagnostic applications to make quantitative decisions by constructing a multivariate system using data analytic methods without any assumption regard

Friction welding of particulate reinforced aluminum composites was performed and the following conclusions were drawn from the study of interfacial bonding characteristics and the relationship between experimental parameters of friction welding and interfacial bond strength. Highest bonded joint efficiency (HBJE) approaching was obtained from the post-brake timing, indicating that the bonding strength of the joint is close to that of the base material. For the pre-brake timing, HBJE was . Most region of the bonded interface obtained from post-brake timing exhibited similar microstructure with the matrix or with very thin, fine-grained layer. This was attributed to the fact that the fine-grained layer forming at the bonding interface was drawn out circumferentially in this process. Joint efficiency of post-brake timing was always higher than that of pre-brake timing regardless of rotation speed employed. In order to guarantee the performance of friction welded joint similar to the efficiency of matrix, it is necessary to push out the fine-grained layer forming at the bonding interface circumferentially. As a result, microstructure of the bonded joint similar to that of the matrix with very thin, fine-grained layer can be obtained.

Counter balance valve is used as one part of hydraulic motor brake system. The function of this valve is to protect over-run or free falling of inertia load. But occasionally the brake system with counter balance valve makes some undesirable problems such as pressure surges or vibrations. These problems may hurt system safety and driver's conformability. Nevertheless, studies on dynamic characteristics of hydraulic system including counter balance valve are very rare, so further accumulation of research results are required. In this study, for the purpose of easy estimation about dynamic characteristics of hydraulic system including counter balance valve, precise formulation describing fluid dynamics and valve dynamics under various boundary conditions were made. The equations obtained in the preceding process include some parameters that must be got experimentally. Flow coefficients of valve and choke are the most significant ones among the parameters. So these parameters are obtained experimentally in this study, and experimental equations obtained from the experimental data were used for numerical calculation. The equations were analysed by numerical integration using Runge-Kutta method, because the equations contain various nonlinear terms. From the numerical analysis, it was verified that the dynamic response of counter balance valve and pressure variation at each elements can be estimated very easily. So the analysing method developed in this study enabled very easy estimating the relation between the performances of counter balance valve and various physical parameters related to the valve. Conclusively, it is said that the results obtained in this study can be used very usefully to develop a new type counter balance valve or to apply the valve to actual hydraulic system for various industrial equipments.