• Proceedings of the KSME Conference
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• 2001.11a
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• pp.766-771
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• 2001

Gas-assisted injection molding is an innovative low-pressure injection molding technique that can provide numerous benefits such as reduced part warpage, excellent surface quality without sink marks, low injection pressure, and greater design flexibility. However, the adoption of gas-assisted injection molding may cause unexpected defects if the gas channel design is not conducted properly. The objective of this paper is to broaden the understanding of gas-assisted injection molding by summarizing the design procedures and experimental results of the gas-assisted injection molding of a 17" flat monitor front cover. The gas channels were designed by using Moldflow(MF/GAS) simulations and a 450 ton injection molding machine with a 5 stage pressure control gas kit was used in the experiments.

• Journal of Advanced Information Technology and Convergence
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• v.9 no.2
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• pp.29-39
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• 2019

Tidal Flats are very important natural resource and various efforts have been made to protect it from environmental pollutions. The projects to monitor the environmental changes by periodically observing the creatures in tidal flats are underway. However, they are being done inefficiently by people directly observing. In this paper, we propose an object segmentation method that can be applied to the applications which automatically monitor the living creatures in tidal flats. In the proposed method, a foreground map representing the location of objects is obtained by using a temporal difference method, and then a superpixel method is applied to detect the detailed boundary of an object. The region of a crab is extracted finally by combining the foreground map and the superpixel information. Experimental results show that the proposed method separates crab regions from a tidal flat image easily and accurately.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.1415-1417
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• 2003

In this study, as the passing of a year, the changes of tidal flat area in Seohan Bay, North Korea was monitored through using Landsat ETM Data and the ancient topological map. The map to present tidal flat distribution characteristic based on the ancient topographical map (1918) was constructed as GIS DB. In addition, a tidal flat distribution map was estimated by using the satellite images with unsupervised classification method. Even though it is difficult to approach to study area, it was possible to gain the data and to monitor the change of the coast tidal flat by comparing to area change yielded.

• 전기의세계
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• v.38 no.10
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• pp.40-44
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• 1989

PDP(Plasma display Panel)는 Gas 방전을 하여 발생하는 빛을 이용하여 화상 표시를 하는 flat panel display이다. PDP는 용도는 여러가지가 있지만 현재 주용도는 Computer Monitor이다. 아직 Orange색 이외의 표시색상은 개발되어 있지 않다. Computer Monitor용의 단색 PDP개발은 최근에 활발히 진행되었다. 16 계조표시가 가능한 10inch 640 * 400 Dot PDP가 DIXY, Matsushita, Oki를 비롯한 여러 회사에서 개발되어 상품화 되었다. 국내에서는 금성사, 대우, 삼성에서 현재 개발을 진행시키고 있고 최근에 삼성에서 Computer Monitor용의 640 * 400 Dot PDP가 개발되었다. 그러나 단색 PDP의 생산 시설 과잉으로 최근에는 일본의 DIXY가 도산하였다. 현재는 단색 PDP로 시장 개척에 한계를 느낀 PDP제조 업체에서 총력을 쏟아 CPT(Color Picture Tube) 대체를 위하여 Full Color PDP를 개발하고 있다.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.3
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• pp.563-572
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• 2020

Tidal flats provide important indicators that inform the condition of the environment, so we need to monitor them systematically. Currently, the projects to monitor tidal flats by periodically observing the creatures in tidal flats are underway. Still, it is done in a way that people observe directly, so it is not systematic and efficient. In this paper, we propose a background modeling method for tidal flat images that can be applied to a system that automatically monitors creatures living in tidal flats using sensor network technology. The application of sensor network technology makes it difficult to collect enough images due to the limitation of transmission capacity. Therefore, in this paper, we propose a method to effectively model the background and generate foreground maps by reflecting the characteristics of tidal flat images in the situation where the number of images to be used for analysis is small. Experimental results show that the proposed method models the background of a tidal flat image easily and accurately.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1067-1070
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• 2005

A large size flat panel LCD-TV must fulfill different requirements than a desktop LCD-monitor: The contrast must be much larger, the viewing angle should be as wide as possible and the switching times must be shorter to allow moving pictures to be displayed naturally. The "Vertically Aligned" technology is most promising to realize such a product. LC-material development for this technology began at Merck about 10 years ago. New materials based on the 1,1,6,7-tetrafluoroindane skeleton were recently synthesized via ortho-metallation and intramolecular Heck cyclization followed by an oxidative fluorination procedure. The materials offer improved properties over liquid crystals currently employed in flat panel LCD-TVs.

• Journal of KIBIM
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• v.13 no.4
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• pp.45-53
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• 2023

The educational benefits and potential of XR as a new medium are well recognized. However, there are still limitations in understanding the specific effects of XR compared to the more widely utilized representation of images on computer monitors. This study therefore aims to demonstrate the differences in effectiveness between the two technologies and to draw implications from a cognitive comparison of three-dimensional objects represented on a flat surface and virtually. The study was conducted a quantitative research method with an experiment involving two independent groups, and the results were tested using regression analysis. The results showed that for low-level, two-dimensional objects, the computer monitor method may be more effective, but above a certain level of complexity, the effectiveness of learning through the monitor tends to decrease rapidly. On the other hand, the group that used extended reality technology showed relatively high comprehension compared to the monitor group even as the complexity increased, and in particular, unlike the monitor group's rapidly decreasing comprehension level, the extended reality technology group showed a trend of decreasing comprehension with the level of complexity, suggesting the potential for compatibility and predictability in the use of technology.

• Computers and Concrete
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• v.21 no.3
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• pp.321-333
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• 2018

Flat-slabs, being a significant structural component, not only reduce the dead load of the structure but also reduce the amount of concrete required for construction. Moreover the use of recycled aggregates lowers the impact of large scale construction to nearby ecosystems. Recycled aggregate based concrete being a quasi-brittle material shows enormous cracking during failure. Crack growth in flat-slabs is mostly in sliding mode (Mode II). Therefore sufficient sections need to be provided for resistance against such failure modes. The main objective of the paper is to numerically determine the ultimate load carrying capacity of two self-similar flat-slab specimens and validate the results experimentally for the natural aggregate as well as recycled aggregate based concrete. Punching shear experiments are carried out on circular flat-slab specimen on a rigid circular knife-edge support built out of both normal (NAC) and recycled aggregate concrete (RAC, with full replacement). Uniaxial compression and bending tests have been conducted on cubes, cylinders and prisms using both types of concrete (NAC and RAC) for its material characterization and use in the numerical scheme. The numerical simulations have been conducted in ABAQUS (a known finite element software package). Eight noded solid elements have been used to model the flat slab and material properties have been considered from experimental tests. The inbuilt Concrete Damaged Plasticity model of ABAQUS has been used to monitor crack propagation in the specimen during numerical simulations.

• Journal of IKEEE
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• v.23 no.2
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• pp.606-613
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• 2019

In this paper, a new method for flat sweeping automatic hold of wavelength swept laser has proposed. Through the performance test on the implemented laser, even 5 hours passed, the flat sweeping has held up well, and 56nm flat sweeping range, 1kHz sweeping frequency, and 8.8mW average optical power were obtained. This showes that the proposed can eliminate the necessity of hand-operated polarization control required for previous swept lasers in case of long time operation and also optical spectrum analyzer needed to monitor the sweeping spectrum status.

• Progress in Medical Physics
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• v.13 no.4
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• pp.202-208
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• 2002

The purpose of this study is to evaluate the monitor unit obtained from various methods for the treatment of superficial cancers using electron beams. Thirty-three breast cancer patients who were treated in our institution with 6, 9, and 12 MeV electron beams, were selected for this study. For each patient, irregularly shaped treatment blocks were drawn on simulation film and constructed. Using the irregular blocks, monitor units to deliver 100 cGy to the dose maximum (dmax) were calculated from measurement and three-dimensional radiation treatment planning (3D RTP) system (PINNACLE 6.0, ADAC Laboratories, Milpitas CA) Measurements were made in solid water phantom with plane parallel (PP) chamber (Roos, OTW Germany) at 100 cm source-to surface distances. CT data was used to investigate the effect of heterogeneity. Monitor units were calculated by overriding CT values with 1 g/㎤ and in the presence of heterogeneity. The monitor unit values obtained by the above methods were compared. The dose, obtained from measurement in solid water phantom was higher than that of RTP values for irregularly shaped blocks. The maximum differences between monitor unit calculated in flat water phantom at gantry zero position were 4% for 6 MeV and 2% for 9 and 12 MeV electrons. When CT data was used at a various gantry angle the agreement between the TPS data with and without density correction was within 3% for all energies. These results indicate that there are no significant difference in terms of monitor unit when density is corrected for the treatment of breast cancer patients with electrons.