• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.1
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• pp.114-130
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• 2016

This research provides practical data to develop UV protection masks and dust protection masks. It surveyed uncomfortable factors and significant characteristics for masks. It used 653 subjects 20-79 years old and performed the research from April to May in 2014. Wearing masks at outdoor activities is not widely popular yet, but golf players, mountaineers and old people were quite interested in masks. People mainly wore a basic shape mask, but main age group of each mask shape was different. People usually prioritized the protection function and comfort of wearing over design; however, women, young generation and people attending to outdoor activities longer than 1 hour considered design quite important. People going on picnic or camping consider mask characteristics most important. Therefore, various mask shapes and protective functions should be developed to reflect consumer needs. Meanwhile, the discomfort levels of masks were not too high, but old people felt more discomfort than young people. The most discomfort factors were 'other's eye', 'distracting face movement' and 'feeling of foreign object'. They also mentioned falling problem of C shape mask and short-rib shape mask, and asked for a 'tighter fit' at the ear.

• The Journal of Korean Physical Therapy
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• v.12 no.2
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• pp.229-238
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• 2000

A properly prescribed wheelchair may be able to normalize tone. decrease pathologic reflex activity, improve postural symmetry, enhance range of movement, maintain and/or improve skin conduit)n. increase comfort and sitting tolerance, decrease fatigue, and improve function of the autonomic nervous system. Whereas a poorly prescribed one can actually exacerbate the problems associated with a disability. Maintained for longer without relief, pressure concentrations may also lead to tissue breakdown. Pressure sores continue to be a major problem for many disabled individuals. Many groups of disabled individuals have a very high incidence of pressure sores, including those individuals with spinal cord injuries. hemiplegia, multiple sclerosis. cancer. and the disabled geriatric population. It is important to understand the factors which predispose an individuals to the development of a pressure sores. Those factors can divided into extrinsic factors, related to the individual's immediate environment and intrinsic factors. related to their medical or physical condition. Pressure sores are generally preventable through sensible pressure management based on an understanding of the causes of pressure sores, risk factors and methods of redistributing pressure.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.6 no.4
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• pp.1171-1187
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• 2012

A depth adjustment method for visual fatigue reduction for depth-image-based rendering (DIBR) system is proposed. One important aspect of the method is that no calibration parameters are needed for adjustment. By analyzing 3D image warping, the perceived depth is expressed as a function of three adjustable parameters: virtual view number, scale factor and depth value of zero parallax setting (ZPS) plane. Adjusting these three parameters according to the proposed parameter modification algorithm when performing 3D image warping can effectively change the perceived depth of stereo pairs generated in DIBR system. As the depth adjustment is performed in simple 3D image warping equations, the proposed method is facilitative for hardware implementation. Experimental results show that the proposed depth adjustment method provides an improvement in visual comfort of stereo pairs as well as generating comfortable stereoscopic images with different perceived depths that people desire.

• Journal of Dental Rehabilitation and Applied Science
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• v.30 no.2
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• pp.152-158
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• 2014

To fabricate removable partial denture which provide patient's comfort and maintain oral health, cast fabrication which reproduce anatomical and functional state of mouth is needed. Diagnostic cast and master cast are produced through the process of preliminary impression and final impression taking. Both of remaining teeth and edentulous area should be well taken in removable partial denture impression. According to the supporting type of partial denture, impression material and method can be changed. Therefore, understanding of impression procedure is essential for the accurate clinical application.

• Smart Structures and Systems
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• v.5 no.3
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• pp.261-277
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• 2009

A fuzzy-sliding mode controller is presented to control the dynamics of semi-active suspension systems of vehicles using magneto-rheological (MR) fluid dampers. A full car model is used to design and evaluate the performance of the proposed semi-active controlled suspension system. Four mixed mode MR dampers are designed, manufactured, and integrated with four independent sliding mode controllers. The siding mode controller is designed to decrease the energy consumption and maintain robustness. In order to overcome the chattering of the sliding mode controllers, a fuzzy logic control strategy is merged into the sliding mode controller. The proposed fuzzy-sliding mode controller is designed and fabricated. The performance of the semi-active suspensions is evaluated in both the time and frequency domains. The obtained results demonstrate that the proposed fuzzy-sliding mode controller can effectively suppress the vibration of vehicles and improve their ride comfort and handling stability. Furthermore, it is shown that the "chattering" of the sliding mode controller is smoothed when it is integrated with a fuzzy logic control strategy. Although the cost function of the fuzzy-sliding mode control is a slightly higher than that of a classical LQR controller, the control effectiveness and robustness are enhanced considerably.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.15 no.10
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• pp.879-887
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• 2003

Buildings with heating and cooling systems have been increased, since the requirement of thermal comfort for residents is grown. Heating and cooling systems, have been changed from two separate systems to one multi-function system which includes both heating and cooling. Especially, heat pump heating and cooling system has been adopted for general classrooms in schools since education environment improvement project has been launched. This research suggests the best option for the heat pump heating and cooling system in educational buildings through economic assessments for four alternative systems based on electric heat pump (EHP) and gas engine driven heat pump (GHP), which are most widely used for elementary, middle and high schools. The model buildings are in the Y high school which has 24 classes of new construction building, which will be built soon. Annual energy consumption for alternative systems uses BECS 3.10, which can be used for system simulation.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.435-442
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• 2004

Tilting train allow the train to pass curve at higher speed without affecting passenger comfort. As the tilting trains run curve track about 30$\%$ higher than non-tilting trains, the centrifugal force and dynamic force will be higher. Therefore it is very important for tilting train to ensure safety against derailment, and to reduce the lateral track forces by applying light-weight design, optimized suspension design and steering mechanism. The 180 km/h Korean Tilting Train(TTX) which is now developing as a part of the Korean National R & D project, was designed and analytically verified to meet these special requirements. This paper describes the analytic study to verify the safety against derailment, especially on the wheel unloading in case of tilting actuation. The severest curve geometry and curving speed was assumed, the tilting control pattern was also assumed as trapezoidal force function applied to tilting bolster and bogie frame. For the comparison, the operation with the speed of tilting train without tilting actuation was numerically simulated and the operation with the balanced speed without tilting actuation was also numerically simulated. Through the numerical simulation of various operating case, we found that derailment quotients, wheel unloading and Q/P was not affected by tilting actuation and that the bogie of TTX was nicely designed to satisfy the safety against the derailment.

• Journal of the Korea Safety Management & Science
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• v.19 no.1
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• pp.103-114
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• 2017

The objective of this study is to analyze the needs and determine the requirements of elder drivers for effectively using In-vehicle Information System (IVIS), by reducing cognitive and physical impact on this vulnerable group. The persona method was used to determine the relevant characteristics of older drivers. Task analysis was performed in order to obtain general interaction problems of the personas when using a common function of recent days IVIS. The results were classified in the different usability goals as general requirements, specific needs. This study suggest improvement directions in order to develop an elderly friendly IVIS; in addition, different usability metrics were suggested. In this way, elder drivers would easily interact with new powerful functions supplied by IVIS of modern cars; while improving safety and comfort of an rapidly aging society.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.68-77
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• 2018

Regarding demand response (DR) by residential users (R-users), the users try to reduce electricity costs by adjusting their power consumption in response to the time-varying price. However, their power consumption may be affected not only by the price, but also by user convenience for using appliances. This paper proposes a methodology for appliance scheduling (AS) that considers the user convenience based on historical data. The usage pattern for appliances is first modeled applying the copula function or clustering method to evaluate user convenience. As the modeling results, the comfort distribution or representative scenarios are obtained, and then used to formulate a discomfort index (DI) to assess the degree of the user convenience. An AS optimization problem is formulated in terms of cost and DI. In the case study, various AS tasks are performed depending on the weights for cost and DI. The results show that user convenience has significant impacts on AS. The proposed methodology can contribute to induce more DR participation from R-users by reflecting properly user convenience to AS problem.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.6 s.111
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• pp.658-664
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• 2006

Shock vibrations are usually experienced in vehicles excited by impulsive input, such as bumps. The frequency weighting functions of the current standards in ISO 2631 and BS 6841 are to help objectively predict the amount of discomfort of stationary vibration. This experimental study was designed to develop frequency weighting shape for shock vibration having various fundamental frequencies from 0.5 to 16Hz. The specks were produced from the response of single. degree-of-freedom model to a half-sine force input. Fifteen subjects used the magnitude estimation method to judge the discomfort of vertical shock vibration generated on the rigid seat mounted on the simulator. The magnitudes of the shocks, expressed in terms of both peak-to-peak value and un-weighted vibration dose values (VDVs) , were correlated with magnitude estimates of the discomfort. The frequency weighting shapes from the correlation were developed and investigated having nonlinearity due to the magnitude of the shock.