• 한국산업융합학회 논문집
• /
• 제8권4호
• /
• pp.197-204
• /
• 2005

It is well known that pipelines have the highest capacity and are the safest and least environmentally disruptive form of transporting oil and gas. However, pipeline damages caused by both internal and external corrosion is a major concern threatening the reliability of oil and gas transportation and the soundness of pipeline structure. In this study, we estimated the expected allowable damage defect by comparing the ASTM B31G code which has been developed as the evaluation method of reliability and incident prevention of damaged pipelines based on the amount of loss due to corrosion and the yield strength of materials to a modified theory considering diverse detailed corrosional forms. Furthermore, we suggested the method that estimates the expected life span of used pipelines by utilizing the reliability method based on major variables such as, the depth and length of damage and corrosional rate affecting the life expectancy of pipelines.

• 한국안전학회지
• /
• 제21권2호
• /
• pp.1-6
• /
• 2006

It is well known that pipelines have the highest capacity and are the safest and least environmentally disruptive form of transporting oil and gas. However, pipeline damage caused by both internal and external corrosion is a major concern threatening the reliability of oil and gas transportation and the soundness of the pipeline structure. In this study, we estimate the allowable damage by comparing the ASTM B31G code to a modified theory considering diverse detailed corrosive forms. The ASTM B31 G code has been developed as the evaluation method for reliability and incident prevention of damaged pipelines based on the amount of loss due to corrosion and the yield strength of materials. Furthermore, we suggest a method for estimating the expected life span of used pipelines by utilizing the reliability method based on major variables such as the depth and length of damage and the corrosion rate affecting the life expectancy of the pipelines.

• International journal of advanced smart convergence
• /
• 제9권1호
• /
• pp.70-81
• /
• 2020

Plastics that we use and simply throw away have a life span of about 500 years and barely decompose. The practice of producing and using common plastics needs to be challenged. Until now, they have been useful in the industrial structure of mass production, but it can be said that there is a lack of research into new materials to introduce and apply in terms of material recycling. As a result of this, we have come to the uncomfortable realization of the fact that we cannot incinerate or reuse these precious resources indiscriminately. No matter how well-designed a product is, it has a competitive advantage if production and consumption activities, waste, collection, sorting and treatment are considered in terms of a continuous cycle, and in this respect, Extended Producer Responsibility (EPR) can help. We are implementing the EPR system, and active industrialization in the field of recycling is required, which is also a challenge for producers to participate actively in recycling and seek to save and recycle resources in design and manufacturing. Against this backdrop, We would like to examine the possibilities, through various studies and developments on product design of recyclable materials, which is being conducted mainly in Europe. In particular, we would like to examine the methods, and value of solving environmental problems and the active efforts to achieve this in the design world, and in particular the case of product design using recycled plastics.

• 한국주거학회논문집
• /
• 제26권6호
• /
• pp.139-146
• /
• 2015

In this study, the plane type of main building relics of unified Silla period house site which excavated in Gyeongju city after 1990s was classified and the architectural characteristic of them was investigated. The chronology of building relics in Silla capital city site was mostly known as 8-9th century, and by standard of column arrangement, the plane types of them could be classified as grid type, front veranda-grid type, outer column type. The outstanding characteristic of plane is wide span and open front veranda. In most relics the span were over 4 meters, and inner foundations for small post and strip foundation were found between columns. The front veranda added type buildings were composited of enclosed main room and open front veranda, and column arrangement of them dose not fall into line in most case. Thus it thought that the structures of enclosed main room and open front veranda were independent. The interior space of enclosed main room were divided two rooms by partition wall in some case. In this case, one room is enclosed by wall, and the other room has open front side. This plane is considered for the pleasant life in cold winter and hot summer.

• Steel and Composite Structures
• /
• 제26권2호
• /
• pp.227-239
• /
• 2018

Integral abutment bridges (IABs) have no joint across the length of bridge and are therefore also known as jointless bridges. IABs have many advantages, such as structural integrity, efficiency, and stability. More importantly, IABs have proven to be have both low maintenance and construction costs. However, due to the restraints at both ends of the girder due to the absence of a gap (joint), special design considerations are required. For example, while replacing the deck slabs to extend the service life of the IAB, the buckling strength of the steel girder without a deck slab could be much smaller than the case with deck slab in place. With no deck slab, the addition of thermal expansion in the steel girders generates passive earth pressure from the abutment and if the applied axial force is greater than the buckling strength of the steel girders, buckling failure can occur. In this study, numerical simulations were performed to estimate the buckling strength of typical steel girders in IABs. The effects of girder length, the width of flange and thickness of flange, imperfection due to fabrication and construction errors on the buckling strengths of multiple and single girders in IABs are studied. The effect of girder spacing, span length ratio (for a three span girder) and self-weight effects on the buckling strength are also studied. For estimation of the reaction force of the abutment generated by the passive earth pressure of the soil, BA 42/96 (2003), PennDOT DM4 (2015) and the LTI proposed equations (2009) were used and the results obtained are compared with the buckling strength of the steel girders. Using the selected design equations and the results obtained from the numerical analysis, equations for preventing the buckling failure of steel girders during deck replacement for maintenance are presented.

• Architectural research
• /
• 제3권1호
• /
• pp.29-36
• /
• 2001

Concern about global environment has been increasing in recent years. Efforts to minimize the environmental impact to the globe as well as human beings have increased, especially in the late twentieth century. The study researches one of the solutions for the environmentally friendly building construction, which can contribute to sustaining the world environment. Assessment and proposals are made for high-rise apartments, one of the most popular construction types nowadays in Korea. Since the volume of high-rise apartment construction is so great, a small improvement in each building will make a great contribution. Assessments are made over the life-span of apartment buildings. A tool named EIAHA (Environmental Impact Assessment for High-rise Apartment) has been made through references from western examples, mainly in the UK. The components of EIAHA include passive design strategies, building materials, energy consumption during building operation and management/maintenance. Although the issues are on a global scale, solutions are sought on regional scale. Korean high-rise apartments are assessed with the tool and suggestions for sustainable development are made mainly for improvement of embodied energy of building materials and the life of buildings.

• 대한기계학회논문집A
• /
• 제28권1호
• /
• pp.31-39
• /
• 2004

This paper presents design solutions for cam type transfer unit in which feeding, lifting, and clamping motions are generated by cams. In order to achieve faster transfer motion, each designed cam must satisfy the given specifications such as velocity, acceleration, jerk, pressure angle, cam thickness, and torque. To reduce absolute torque magnitude and torque variation, a conjugate cam and a torque reduction cam are used respectively. The conjugate cam eliminates the redundant pre-load by using complementary cam to avoid jumping between a cam and a follower. The torque reduction cam reduces the torque variation by applying opposite torque to a cam shaft. The experimental result shows the reductions of the absolute torque value and torque variation. The improvement of working speed and life span of cam type transfer unit can be expected.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2003년도 춘계학술대회 논문집
• /
• pp.844-847
• /
• 2003

This thesis suggests design considerations and solutions for cam type transfer unit in which feed, lift, and clamp motions are occurred by cams. For fast transferring and avoiding cam breakage, each designed cam must satisfy the given specifications such like velocity, acceleration, jerk, pressure angle, ram thickness, and torque. To reduce absolute torque magnitude, conjugate cam is suggested. Conjugate cam eliminates the redundant pre-load by using complementary cam and follower to avoid jumping between them. The result from the prototype shows the reductions of the absolute torque value, and it indicates that conjugate cam could enhance the working speed of cam type transfer unit and extend of the life span of cam type transfer unit.

• 반도체디스플레이기술학회지
• /
• 제7권1호
• /
• pp.59-65
• /
• 2008

There are no products, systems to manage health and detect security for infant, the old and the weak in Korea. Recently, the concerns of parents are increasing more about all of children(baby, infant, etc) because rate of birth is decreasing gradually. Also, the average span of human life is on an increasing trend according to well-being and evolution of medical treatment. Therefore, this treatise analyzed problems in managing and following-up infant, the old and the weak at present. By using TRIZ to solve problems, we devised new conceptional ideas, detail designs to manage health, detect security, cope with correspondences for them and developed the prototype and tested it. Excellent performances are proved through various field test.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
• /
• 제24권4호
• /
• pp.7-15
• /
• 2018

Purpose: The life span of a hospital building is short. This is because the building will have to be built up due to the fact that it can not cope with the new medical environment, it can not be replaced due to low floor height, lack of land. The purpose of the hospital building master plan is to find a way to fulfill its role in the long term. Methods: Comparison the proposals submitted by the master plan and the proposals submitted by the hospitals, the case of three hospitals that have established a master plan for the past three years. In addition, interviews with the designers who participated in the design competition and the administrator of hospital about the variables that occurred during the business process. Results: The result of this study can be summarized into four points. The first one is that master plan is changed by administrator of hospital so that Thy need to understand about the role of master plan. And next is to protect reduction of the project cost. Third, continuous participation of master plan researchers in following projects is good to communicate with administrator and designer. The last one is empathy of master plan by designer and users. Implications: It is necessary to reduce changing of master plan in design process for sustainable managing of hospital.