• Journal of International Academy of Physical Therapy Research
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• v.7 no.2
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• pp.1051-1055
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• 2016

The purpose of this study was to investigate the effect of the screen size of smart devices on the bending angle of the cervical spine. The subjects of this study were 30 healthy adults(15 men and 15 women) who used smartphones and tablet PC(personal computer). The changes in the bending angle of the upper and lower cervical spine were measured in the subjects after they had used a smartphone and a tablet PC for 300 seconds each. To make sure that all subjects began in the same starting position, an angle-measuring instrument was used to set the angles of the ankle, knee, hip, and arm joints to 90 degree. The subjects were asked to keep the trunk straight. They were asked to hold a smartphone in their hand and to bend their neck so that they could look down at the screen. Once they began using the smartphone in this manner, they were free to change their posture. We used a paired t-test to compare the bending angle of the cervical spine on subjects who used smartphones and tablet PC in the long-term and short-term there production error of cervical and the significance level was cervical. The results showed that, when using a smartphone and a tablet PC for 300 seconds, there was no significant difference in the bending angle of the upper cervical spine(p>.05), although there was a significant difference in the bending angle of the lower cervical spine(p<.05).

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.520-523
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• 2006

Lately, development of multimedia industry has multimedia data serviced through various wire wireless communicating environment. These multimedia data is displayed on the device of various sizes such as mobile telephone, PDA, notebook, PC. Therefore, there has needed to resize multimedia data appropriate to the screen size of user's display device. In this paper, we propose the method to resizing H.264 videos sequence fitting to the screen size of user's display device. The existing most methods reduce the size of video sequence, but this paper proposes the upsampling method. The results show the proposed method upsamples video sequences without blocking effects.

• Journal of the Ergonomics Society of Korea
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• v.29 no.5
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• pp.771-782
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• 2010

Today, the number of elderly drivers who use navigation is increasing with the growing number of elderly drivers. The purpose of this study is to provide guidelines on the interface of car navigation for elderly users. To extract significant factors which were distinguished between young and elderly users, both young and elderly users executed the driving test by installing two car navigation alternatives. The analysis was conducted through t-test. The results show that significantly different factors were the number and the meaning of the menu items in the initial screen, the location and the meaning of the menu icons in the map screen, the ease of search of the menu and the text size in the menu screen. Improvements for the factors of the initial screen and map screen were made with reference to ergonomic guidelines, and suggested through experiments comparing design alternatives for the menu screen. Design alternatives were made through a combination of investigative variables, and the analysis was conducted through ANOVA. The results show that Alternative 7 (the location of the tab was placed at the bottom, menu representation was done with the text font size of 18pt and the location of menu navigation icons was shown at the upper left) was preferred in terms of user's preference and the execution time. So if the suggested menu for elderly users are added to the existing design, both users will satisfy their desires. The guidelines suggested in this study will help the designer of car navigation take elderly users into consideration.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.8
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• pp.526-533
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• 2008

In this study, theoretical super screen vibration analysis has been carried out to predict the dynamic characteristics of interactive waste particles. In order to approach these problems, it is necessary to have a fundamental understanding the screening process and the process of both the remaining and the passed material on a screen with several interacting screen planes based on Soldinger(1999) was discussed. Here, the vibrating screen is composed of three assemblies such as screen, wastes guide, and supported screen as shown in Fig. 1. This model is regarded vibrator as the system of screen fixed tilt plates. Then materials(or particles) of different size is to be separated by using the eccentric vibrator and classifying tilt plates. As well moisturized construction wastes is more efficient to separate than moisture-less it. In processing separate mechanism, the more materials is light, the more staying time is long. Thus much lighter construction wastes(wood, Styrofoam, etc) and heavier materials are separated by staying time delay in a super screen. The design results, separation screen were able to know that small and larger particles are conspicuous difference each motion character according to trajectory particles, and small particles raise the probability in classifying tilt plates.

• Korean Journal of Agricultural Science
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• v.43 no.3
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• pp.496-505
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• 2016

The purpose of this study was to investigate the economic effects of a flame retardant aluminum screen developed by a company Economic effects were analyzed in terms of micro and macro-economic aspects. In the macro-economic aspect, economic effects were analyzed under the assumptions that the total import volume of flame retardant aluminum screen was approximately $50m^2$ in 2015 and that possible import substitution rates were 100%, 80%, and 60%. Results showed economic values of 2.25 billion won (100% import substitution rates), 1.8 billion won (80% import substitution rates), and 1.35 billion won (60% import substitution rates). If existing farms which had been using imported flame retardant aluminum screen replaced it newly developed with the flame-retardant aluminum screen developed in this study at rates of 100%, 80%, and 60%, the farms could save 750 million won, 60 million won, and 45 million won, respectively. Furthermore, the social cost savings from fire prevention could be 1.184 billion won. In the micro-economic aspect, if a farm with a typical-size ($1,000m^2$) greenhouse growing red pepper wanted to install flame retardant aluminum screen instead of generic aluminum screen, the farm may only pay an additional cost of 720,000 won. In comparison, if the farm chose fire insurance instead of flame-retardant aluminum screen, then the farm would pay 21,000,000 won for fire insurance. The above results show that the economic effect of flame retardant aluminum screen developed by the company would be be very efficient compared to the imported one.

• Journal of Korean Institute of Industrial Engineers
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• v.37 no.1
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• pp.30-40
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• 2011

In recent years, driver information systems (DIS's) became popular and the use of DIS's increased significantly. A majority of DIS's provides touch-screen interfaces because of intuitiveness of the interaction and the flexibility of interface design. In many cases, touch-screen interfaces are mainly manipulated by fingers. In this case, investigating the effect of touch-key sizes on usability is known to be one of the most important research issues, and lots of studies address the effect of touch-key size for mobile devices or kiosks. However, there is few study on DIS's. The importance of touch-key size study for DIS's should be emphasized because it is closely related to safety issues besides usability issues. In this study, we investigated the effect of touch-key sizes of DIS's while simulated driving (0, 50, and 100km/h) considering driving safety (lateral deviation, velocity deviation, total glance time, mean glance time, total time between glances, mean number of glances) and usability of DIS's (task completion time, error rate, subjective preference, NASA TLX) simultaneously. As a result, both of driving safety and usability of DIS's increased as driving speed decreased and touch-key size increased. However, there were no significant differences when touch-key size is larger than a certain level (in this study : 17.5mm).

• The Journal of Sustainable Design and Educational Environment Research
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• v.14 no.2
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• pp.37-44
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• 2015

The purpose of this study is to propose the calculation model of CCTV monitor size for school. Literature review analyzed the concept and technical characteristics of CCTV system including equation of object size calculation. Case study showed that the sizes of CCTV monitors installed in the security offices of the six object schools were 19 inches on average. And the numbers of monitor screen partitions were at least 12 on average. Due to too many partitions in small monitors of approximately 19 inches, the faces of the objects of filming in each screen could not be properly identified. Experimental test presented that the vertical length of face image clearly recognized on the screen is at least 20mm. Based on the result, this paper developed the equation for calculating monitor size. Pilot test said that 27inch Monitor is needed for 4 screens. The practitioners of school districts and schools can make appropriate CCTV system environments considering the their own CCTV system conditions.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.572-578
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• 2001

This study is to research the heat transfer characteristics in copper-water heat pipes with screen wick, #100. Recently, the semiconductor capacity of an electronic unit has been larger, on the contrary, its size is smaller than before. As a result, a high-performance cooling system is needed. Experimental variables are inclination angle and temperature of cooling water. The distilled water was used for the working fluid. At a inclination angle ${-6}^{\circ}$, #100 2layer screen mesh is shown the best heat transfer performance.

• Transactions of Materials Processing
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• v.20 no.2
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• pp.93-98
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• 2011

Electroforming is a kind of metal molding technology. After gilding on the possession object(conductivity, nonconductivity) separate it with possession object and produce a part or duplicate. This process has an excellent ability of duplicating detailed figure. To simplify the manufacturing process of a rotary screen, this study was adopted electroforming technology and produced silicon rubber mandrel. Furthermore, to indicate the optimal condition for the acquisition of high-qualified rotary screen product, the experiment was executed with pH, time, sulfamate nickel solution according to density which were the main factors to decide the condition, then compared it with the product made by original "S" company in Holland. As a result, the figure of hole was more obvious and correct. Also the open size increased by more than 2-3%.

• Journal of the Korean Graphic Arts Communication Society
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• v.29 no.2
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• pp.83-92
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• 2011

A inorganic powder EL lamp was made by screen printing technique with phosphor ink and dielectric ink. The thickness change of a phosphor ink layer and a dielectric ink layer were not influenced on dielectric content, but rely on phosphor size and vehicle. Once finishing screen printing technique with phosphor ink and dielectric ink, and its surface has been printed again before not drying of phosphor ink and dielectric ink. Then phosphor ink and dielectric ink were not transferred. The electric capacity of inorganic powder EL lamp was more influenced on dielectric content than the thickness of dielectric ink layer, and it was more dependent on the thickness of phosphor ink layer than the thickness of dielectric ink layer.