• Journal of Welding and Joining
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• v.20 no.4
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• pp.517-524
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• 2002

An overlaying of the seating surfaces of engine valves by OAW, GTAW or PTA weldings are common practice. The OAW method of a lower torch energy density compared to GTAW and PTA methods produces smoother deposits but the pain size at the vicinity of the interface is increased remarkably up to $30~50{\mu\textrm{m}}$ (that of base metal is about $10\mu\textrm{m}$). It's grain coarsening and the solute dilution are related to the decarburizing during OAW could be minimized by reducing the preheating temperature and by maintaining the carbide precipitates in base metal prior to welding. The formation of columnar structures and carbide precipitation zone in the vicinity of the GTAW welded interface, because of the high heat concentration, causes weakened zone on the valve seat face. The width of the reaction boundary zone is about $50\mu\textrm{m}$ for PTA and GTAW overlaying, and about $150\mu\textrm{m}$ for OAW welding. The smaller width of the reaction boundary zone is the less the solute-dilution rate. Thereby PTA welding may be recommended for overlaying of the seating surfaces.

• Journal of the Korea Furniture Society
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• v.18 no.3
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• pp.177-187
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• 2007

Since the 1960s when paper began to use as a structural material in furniture, design, the way of using paper was dramatically changed. Before the 1960s, paper was used mostly in decorative purposes like paper $mach\acute{e}$. The development of consumer culture in the 1960s created a new trend for paper in design. Paper became a material for dresses and chairs. Also, the types of paper that adapted on furniture varies from cardboard, paper tubes, glassine paper, honeycomb, etc. The variation of the material results to make possible to create a new form. Moreover, paperboard was broadly used in current society in such area that mostly structural based as architecture. Paper gives great opportunity not only to consumers to buy furniture in inexpensive price also to manufacturers to produce furniture and to test market easily, Moreover, paper furniture is mostly fun. Therefore, the creation of paper furniture becomes diverse in terms of design concept. This study explored the characteristics of paper furniture responding to social backgrounds by decade. Relation between types of paper and the characteristics is one of main points in this research. This study covers furniture design from the 1960s to present and mostly focuses on seating furniture where paper used as structural material. Researching on patent records and contemporary periodicals gave me helpful information on details of design process and consumer culture.

• IEMEK Journal of Embedded Systems and Applications
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• v.6 no.4
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• pp.209-214
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• 2011

This study suggests a Healthcare System for elderly and disabled who have mobility impairment and use a wheelchair for long time. Seating long time in a wheelchair without reducing pressure causes high risk of developing pressure sores. Pressure sores come with great deal of pain and often lead to develop complication. Not only it takes time and effort to treat pressure sores but also increases medical expenses. Therefore, we will develop a device to help to prevent pressure sores by measuring pressure distribution while seating in a wheelchair and wirelessly send information to user device to check pressure distribution in real time. The equipment to measure body pressure is composed of FSR sitting mat which is a sensor measuring part and an user terminal which is a monitoring part. The designed mat is matrix formed FSR sensor to measure pressure. The sensor send measured data to the controller which is connected to the end of the mat, and then the collected data are sent to an user terminal through a bluetooth. Developing a pressure monitoring system will help to prevent those who have mobility impairment to manage pressure sores and furthermore relieve their burden of medical expenses.

• Journal of the Korean Society of Clothing and Textiles
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• v.44 no.6
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• pp.1107-1119
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• 2020

This study analyzed a subject's body reaction and subjective sensation when wearing a gait-assistive rehabilitation robot. The research method measured skin and clothing surface temperatures for 'seating-standing' and 'walking in place' exercises after wearing a gait-assistive rehabilitation robot. In addition, subjective sensation and satisfaction were evaluated on a 7-point Likert scale. The study results showed that the average skin temperature during exercise while wearing the gait-assistive rehabilitation robot was within a comfortable range. However, during the 'seating-standing' exercise, the skin temperature was slightly lowered. Additionally, the clothing surface temperature tended to be lower than the pre-exercise temperature after all exercises. The subjective sensation evaluation results showed that the wear comfort of the waist part was low during mobility/activity. In addition, an overall improvement in the wear comfort of the robot is necessary. The short-time movement of wearing and walking in the gait-assistive rehabilitation robot did not interfere with the thermal comfort of the body. However, the robot needs to be ergonomically improved in consideration of the long wearing time along with improved material that to satisfy overall wearing comfort.

• Journal of Biomedical Engineering Research
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• v.45 no.2
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• pp.75-80
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• 2024

This research investigates the influence of chair tilt functionality on biometric signals and user comfort, addressing the ergonomic challenges posed by modern sedentary lifestyles. Through an experimental study involving eight male participants, the impact of chair tilt on electromyography (EMG), heart rate, metabolic rate, pressure distribution, and distance between the lumbar spine and the lumbar support part of the chair was measured across different seating postures. The study utilized chairs with both synchronous and non-synchronous tilt mechanisms to explore how adjustments in chair design affect user comfort and physiological responses during prolonged sitting. Key findings suggest that chair tilt functionality can significantly reduce muscle activity and energy expenditure, enhancing user comfort and potentially mitigating health risks associated with prolonged sedentary behavior. Notably, the study revealed a preference among participants for chairs that aligned the rotational center of the tilt with the hip joint, highlighting the importance of this ergonomic feature in enhancing user comfort. Additionally, the research proposes a novel methodology for assessing seating comfort through the analysis of both biometric and physical signals, providing valuable insights for the development of ergonomic chair designs focused on user health and comfort.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.8 no.3
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• pp.205-211
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• 2014

The purpose of this document is to provide basic data helpful in selecting seating device material by examining the affects of polyurethane foam material on seating pressure. In order to achieve this study objective, four seats, 6cm in height, were produced in hardness of: 13, 28, 25, and $45kg/cm^2$. To measure the sitting pressure distribution (depending on the characteristics of the produced seats), 10 healthy subjects participated in the experiment. XSENSOR was used a measuring device, and each seat was mounted on a wheelchair simulation. By analyzing the obtained data with Average Pressure(AP), Peak Pressure(PP,), and Contact Area(CA), the sitting pressure was measured for five minutes on each seat. This experiment showed the following results: There were significant differences between the AP, PP, and CA in the seat material (p<0.5). While the hardness of $18kg/cm^2$ showed low pressure, the hardness of $45kg/cm^2$ showed high pressure. This study also showed that seat material made of polyurethane should be considered when selecting seats. If polyurethane foam is used in seat recommendations, it will be recommended to use $18kg/cm^2$ for the proper hardness of the seat material.

• The Journal of Korean Philosophical History
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• no.29
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• pp.281-309
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• 2010

The aim of this paper is to investigate the origin of prajñāpāramitā thought in Platform-Sutra, because the practices such as No-thought(無念)·No-image(無相)·No-staying(無住), Samadhi for one act(一行三昧), Seating meditation(坐禪) and Non- distinction of calmness and wisdom(定慧一體) are consolidated into the practice of prajñāpāramitā. The practice of No-thought, No-image and No-staying means an absolute stage which cannot be described in words. It is another expression of prajñā-samadhi or practice of prajñā -pāramitā whose concepts originate from Diamond-Sūtra, Vimalakīrtinirdeśa-sūtra, Mahāparinibbāna-sūtra, and Mahāprajñā-pāramitā-Sūtra. Samadhi for one act is to have an insight into the original nature in everyday life, which is a new development of practicing prajñāpāramitā. Seating meditation is another form of expression of Sudden Enlightenment to see into one's original nature(頓悟見性) through practicing prajñāpāramitā. This can be said a new kind of mixture of Buddhadhātu thought and prajñāpāramitā thought. Therefore prajñāpāramitā thought in Platform Sutra comes from Buddhadhātu thought and prajñāpāramitā thought. Those two thoughts consolidated in Platform Sutra, made the starting point of Zen Buddhism. At the same time, they further continued to be systemized into the thought of Zen Buddhism and eventually into the conclusion of Zen sect of Chinese Buddhism.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.589-590
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• 2008

Sound absorption characteristics of audience seating is very important when design and simulate room acoustics of concert halls or multi-purpose auditoriums. Sound absorption characteristics of audience seats were measured in reverberation chamber by varying the row to row spacing and number of audiences. By the increment of the row to row spacing, sound absorption characteristics in mid frequency band was increased. Also, sound absorption was proportionated to the number of audience.

• Communications of the Korean Mathematical Society
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• v.15 no.1
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• pp.123-131
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• 2000

Let {X(t) : t $\geq$B 0} be a Symmetric $\alpha$ Stable and H-Self-similar process with stationary increments. We examine a.s. Holder unboundedness of S$\alpha$S H-sssi Chentsov processes and H-sssi Chentsov fields for order ${\gamma}$>H. Finally, we prove a.s. Holder continuity of S$\alpha$S H-sssi processes with ergodic seating transformations for the case of H>1/$\alpha$.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.206-210
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• 1989

In automobile glass fitting the stud is welded on the window seating panel in order to insert the plastic molding onto the stud. Since this type of process is in general manually done, almost 50% of the output turns out to be failure resulted from work inefficiency and weld inferiority. Therefore, it is required to improve this process for the productivity elevation through the application of the robot.