• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회A
• /
• pp.1303-1308
• /
• 2008

In this study, we researched how to estimate life-stress relationship and acceleration factor through performing accelerated life test and analyzing it. The purpose of this study is to predict life of pneumatic cylinder within short time which is widely used in automation manufacturing line. In design of accelerated life test, we selected operating pressure and load that have the most influence on main failure mode of pneumatic cylinder as accelerated factor. We used two-way factorial design for arranging of test condition to accelerated factor and accelerated level.

• ALGAE
• /
• 제37권4호
• /
• pp.249-264
• /
• 2022

Two genera of the Rhodymeniales, Halopeltis and Leptofauchea, are here reported for the first time from the Hawaiian Islands and represent the deepest records for both genera. Molecular phylogenetic analyses of cytochrome oxidase subunit I (COI), rbcL, and large subunit ribosomal DNA (LSU) sequences for Hawaiian specimens of Leptofauchea revealed one well-supported clade of Hawaiian specimens and three additional lineages. One of these clades is described here as Leptofauchea huawelau sp. nov., and is thus far known only from mesophotic depths at Penguin Bank in the Main Hawaiian Islands. L. huawelau sp. nov. is up to 21 cm, and is the largest known species. An additional lineage identified in the LSU and rbcL analyses corresponds to the recently described L. lucida from Western Australia, and is a new record for Hawai'i. Hawaiian Halopeltis formed a well-supported clade along with H. adnata from Korea, the recently described H. tanakae from mesophotic depths in Japan, and H. willisii from North Carolina, and is here described as Halopeltis nuahilihilia sp. nov. H. nuahilihilia sp. nov. has a distinctive morphology of narrow vegetative axes that harbor constrictions along their length. The current distribution of H. nuahilihilia includes mesophotic depths around W. Maui, W. Moloka'i, and the island of Hawai'i in the Main Hawaiian Islands. Few reproductive characters were observed because of the small number of specimens available; however, both species are distinct based on phylogeny and morphology. These descriptions further emphasize the Hawaiian mesophotic zone as a location harboring many undescribed species of marine macroalgae.

• 전기학회논문지
• /
• 제60권11호
• /
• pp.1993-1999
• /
• 2011

Today, the power utilities is setting on the slow load growth and the aging of power equipment, and then could spend the efforts on the stability of system performance. Asset management may be defined as the process of maximizing corporate profit by maximizing performance and minimizing cost over the entire life cycle of power equipment. Therefore, asset management is great way to fulfill the economic investment and the stability of system performance. This paper presents the application of effective asset managem ent from an economic perspective. A proposed method is considering the life cycle analysis using life cycle cost methodology for hydro-generator during the total life cycle. The life cycle cost methodology include a way to calculating maintenance and operating costs. The proposed method will be expected to play an important role in investment decision making considering economic evaluation.

• Journal of Mechanical Science and Technology
• /
• 제20권4호
• /
• pp.473-481
• /
• 2006

Predicting fatigue life by numerical methods was almost impossible in the field of rubber materials. One of the reasons is that there is not obvious fracture criteria caused by nonstandardization of material and excessively various way of mixing process. But, tearing energy as fracture factor can be applied to a rubber-like material regardless of different types of fillers, relative to other fracture factors and the crack growth process of rubber could be considered as the whole fatigue failure process by the existence of potential defects in industrial rubber components. This characteristic of fatigue failure could make it possible to predict the fatigue life of rubber components in theoretical way. FESEM photographs of the surface of industrial rubber components were analyzed for verifying the existence and distribution of potential defects. For the prediction of fatigue life, theoretical way of evaluating tearing energy for the general shape of test-piece was proposed. Also, algebraic expression for the prediction of fatigue life was derived from the rough cut growth rate equation and verified by comparing with experimental fatigue lives of dumbbell fatigue specimen in various loading condition.

• International Journal of Human Ecology
• /
• 제8권1호
• /
• pp.109-116
• /
• 2007

Leisure time is a critical part of modern life and is increasingly important in modern society. Therefore, analyzing expectations and values of leisure and researching leisure practices are integral in measuring the quality of life. In this respect, differences between values and attitudes leading to the ideal leisure life and the actual leisure life could provoke negative influence on our lives, further, decreasing quality of life. Therefore, classifying leisure lifestyle through analyzing value of lifestyle and the actual state of leisure precisely is very necessary. Leisure lifestyle could be very useful standard satisfying various desires and demands related to leisure. In the research, we surveyed 3,000 people over 10 years of age, one on one interview method, asking value of life behaviors (Individualism vs. Collectivism, Pro-Stability vs. Pro-Change, Statistical way of life vs. Active way of life, Family-centered life vs. Work-centered life) and practices of leisure life (With whom, How frequently, Where, For what) in respect to both value and behaviors. Through this survey, five groups of leisure life type have been identified; "Community-oriented Type", "Cocoon Type", "Family-oriented Type", "Personal-stability Type" and "Multiplicity Type". These leisure lifestyles would provide effectual alternatives for reducing gaps between expectations for ideal leisure life and actual life. Furthermore, this could be used for ground work to develop measurements for satisfying various leisure demands.

• 한국수학교육학회지시리즈E:수학교육논문집
• /
• 제28권3호
• /
• pp.423-429
• /
• 2014

초행길 인생인 우리들이 시행착오를 줄이려면, 인류가 이룩한 인생살이의 교훈과 노하우를 미리미리 교육을 통해 깨닫는 것이 필요하다. 교육현장에서 미시적 탐구 위주의 수학교육 연구영역을 삶에 관계되는 영역까지 확장하여, 인생살이를 효율적으로 통찰하고자 한다. 본 연구는 인생살이를 살피는 방법들을 크게 네 가지로 분류하고, 인생살이 통찰에 필요한 수학적 모델을 경험 가능한 일상영역에서 찾을 수 있도록 설계하였다. 이렇게 만들어진 모델세계로 인생살이를 통찰하는 예를 통해, 수학적 모델링으로 인생살이를 통찰하는 방법을 새롭게 소개한다.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2004년도 추계학술대회
• /
• pp.172-177
• /
• 2004

Fatigue life prediction is based on fracture mechanics and database which is established from experimental method. Rubber material also uses the same way for fatigue life prediction. But the absence of standardization of rubber material, various way of composition by each rubber company and uncertainty of fracture criterion makes the design of fatigue life by experimental method almost impossible. Tearing energy which has its origin in energy release rate is evaluated as fracture criterion of rubber material and the applicability of fatigue life prediction method are considered. The system of measuring tearing energy using the principal of virtual crack extension method and fatigue life prediction by the minimum number of experiments are proposed.

• 가정과삶의질연구
• /
• 제15권2호
• /
• pp.71-71
• /
• 1997

This study aims ai the extraction of what is universally to be taught in modern Korean Families and its scalization. That is, it attempts to provide the criterion by which we can determine what to teach adolescent in the family, not in society or school. For this purpose, this study firstly reviews the preceeding studies on the subject. As a result of the review, we postulate the hypothetical structure consisting of 11 domains. Secondary, we gather the parent's view on the topic by interviewing 496 parents with teenagers. On the basis of this study, we can construct the questionnaire(Likert scale; 5 point). After we conduct an extensive empirical research(346 parents) in order to generalize 195 items of the workedout questionnaire. We apply factor analysis(principal axis factoring, oblique (promax) rotation) in the verification of the validity. As the consequence, we select 66 items consisting, 10 factors, which explain 68% of common variance. We name the 10 educational factors extracted in the scale as follows ; The Sense of Value, Communal Society, Sex, Esteem for an ancestor & a traditional way of life, Parent-Child Relationship, the Culture life within the family, The Guide of Learning Way, Setting up the way of life, The control of one's life, Friendship. The reliability of the scale is the cronbach =0.91 which turns out to be satisfactory.

• 대한지리학회지
• /
• 제39권1호
• /
• pp.102-115
• /
• 2004

As a household's residential location is closely related to its workplace and place of education, the urban exodus of city dwellers changes their ways of commuting to workplace and attending school. This paper examines the influence of urban exodus on the change of a way of life through relations between residential location and modes of commuting. Despite moving to the countryside, exurban migrants still want to experience rural health without abandoning the city lifestyle. However, they are faced with various difficulties in commuting to workplace and attending school, because suburban and exurban areas have poor accessibility to the central city. In order to overcome these problems, most of them choose "the residential segmentation of the family" through which the head of the family commutes to the city from his or her family home in exurban areas and children go to school from their second home in the central city, or try "to link commuting to workplace with attending school".

• 복식
• /
• 제52권6호
• /
• pp.165-179
• /
• 2002

This paper begins with the thesis that the so-called 'Be Slow' Movement has not only affected the contemporary life style but also the current fashion trend in the West as well as in Korea. The influence of the 'Be Slow' Movement on the everyday life of Western and Korean society can be documented by recent books, news reports, and many articles from various kinds of mass media and fashion magazines since the year 2000. The results of this study can be summarized as follows. First. the 'Be Slow' Movement is a new cultural phenomenon and very different from that of the past century. It has emerged very recently and it could affect the life style o( its followers for a long period of time. Second, the influence of 'Be Slow' Movement on everyday life can be witnessed in many behavioral choices. such as the preference of organic food and natural cooking for food and the preference of rural life and a green patch of land for housing. Some aspects of the way of rearing the children and long-term planning of one's life are also under the influence of 'Be Slow' Movement. In a way. the life style Proposed by the 'Be Slow' Movement is somewhat similar to that of 'Bobos'. Third, the influence of 'Be Slow' Movement on the current fashion trend can be observed in the appreciation of time-consuming labour and increased usage of D.I.Y. clothing. The higher value of fashion goods with handcrafted part or scarce luxury item are good examples of the influence by the 'Be Slow' Movement. One can say that the 'Be Slow' Movement is not retrogression, but a re-creation of time and space to be grateful for one's life. Thus, it is not anti-technology but a commercialism with technology in order to enhance the quality of life and to place people in the center of production and consumption. Consequently, one may say that the 'Be Slow' Movement is a appropriate and affluent way of living.