• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1809-1811
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• 1999

In recent years, attempts have been made to greatly improve the display quality of active-matrix liquid crystal display devices, and many techniques have been proposed to solve such problems as gate delay, feed-through voltage and image sticking. Gate delay is one of the biggest limiting factors for large-screen-size, high-resolution thin-film transistor liquid crystal display (TFT/LCD) design. Many driving method proposed for TFT/LCD progress. Thus we developed gate driving signal generator. Since Pixel-Design Array Simulation Tool (PDAST) can simulate the gate, data and pixel voltages of a certain pixel on TFT array at any time and at any location on an array, the effect of the driving signals of gate lines on the pixel operations can be effectively analyzed.

• International Journal of Naval Architecture and Ocean Engineering
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• v.6 no.2
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• pp.418-430
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• 2014

In this paper, a modelling technique for simulating self-propelled ships in waves is presented. The flow is modelled using a RANS solver coupled with an actuator disk model for the propeller. The motion of the ship is taken into consideration in the definition of the actuator disk region as well as the advance ratio of the propeller. The RPM of the propeller is controlled using a PID-controller with constraints added on the maximum permissible RPM increase rate. Results are presented for a freely surging model in regular waves with different constraints put on the PID-controller. The described method shows promising results and allows for the studying of several factors relating to self-propulsion. However, more validation data is needed to judge the accuracy of the model.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.51.2-51.2
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• 2010

Efficient and durable electrical energy storage is one of the major factors limiting the wide-spread adoption of renewable energy. Since lithium-ion batteries (LIBs) were first commercialized in the early 1990s, LIBs have emerged as an important energy storage device for portable electronics. LIBs are very desirable because of their high energy storage per volume and per mass. However, LIBs with high energy and power as well as higher stability are needed for their use in a variety of energy storage applications such as MEMS devices, PDA, plug-in hybrids, all-electric vehicles and large scale utility systems. In this talk, I will discuss present energy perspective, especially energy storage and its role in renewable energy. After that I will discuss the recent advances in nanostructured materials and interface engineering that have led to the achievement of improved Li-ion batteries. Finally I will talk aboutcritical issues that need to be addressed to obtain further improvements in Li-ion batteries.

• IEIE Transactions on Smart Processing and Computing
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• v.6 no.3
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• pp.168-174
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• 2017

Videos recorded on surveillance cameras or by car black boxes at night have distorted images due to illumination variation. Therefore, it is difficult to analyze morphological characteristics of objects, and it is limiting to use such distorted images as evidence in traffic accidents. Image restoration is performed by amplifying the brightness of nighttime images using linearized gamma correction to increase their contrast (which destroys visual information) and by minimizing degradation factors caused by irregular traveling.

• Applied Science and Convergence Technology
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• v.24 no.4
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• pp.96-101
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• 2015

Quantitative evaluation of photocatalytic activity of oxide nanoparticles in aqueous solution is quite challenging in that the kinetic reaction rate is determined by a complicated interplay among various limiting factors such as light scattering and absorption, diffusion and adsorption of reactants in condensed liquid phase, photoexcited charge separation and recombination rate, and the exact nature of active sites determined by detailed morphology and crystallinity of nanocrystals. Here, we present our simple experimental results showing that the kinetic regime of a typical photocatalytic degradation experiment over UV-irradiated $TiO_2$ nanoparticles in aqueous solution is in that dominated by the photoactivity of $TiO_2$ and its concentration. This result lays a firm ground of using the measured kinetic reaction rate in evaluating photocatalytic efficiency of oxide nanocrystals under evaluation.

• The Korean Journal of Ecology
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• v.9 no.1
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• pp.33-40
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• 1986

The distribution of giant duckweed (Spirodela polyrrhiza) and small duckweed (Lemna aequinoctialis) was investigated at lead-zinc mine area and the limiting factors for their distribution were studied by laboratory experiments. The metal investigated of water affected on the growth of giant duckweed and small duckweed. Under filed conditions, both giant duckweed and small duckweed did not persist at more acidic conditions than pH 4.8 or at conditions more than 0.30 ppm of Cd concentration. Giant duckweeds were intolerable, under conditiions with less than 0.30 ppm of Cd and above than 0.07ppm of Zn, but small duckweeds were tolerable under conditions of more than 0.07 ppm of Zn concentration. However, neither can live above 7.50ppm of Zn concentration. These field observations corresponded with the results of the laboratory experiments.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.125.1-125
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• 2003

Pepper anthracnose is one of the major limiting factors in pepper production. Boring last over 10 years, Colletotrichum gloeosporioides has been known as the most prevalent species among five Colletotrichum spp. involved as anthracnose causing agents. Recently, however, the change of major species with pepper anthracnose has been proposed. Identification study was peformed on 12 test isolates collected from anthracnose disease symptoms on pepper during 2001-2002 and 25 reference isolates obtained from several other host plants. The identification of the isolates with morphological observation and IfS region sequence comparison resulted that 11 ones from 12 test isolates colleted from pepper anthracnose during 2001-2002 were identified as C. acutatum. PCR using species-specific primers designed from ITS region sequence suggested a rapid diagnosis method in identifying C. acutatum from C. gloeosporioides.

• Journal of Electrochemical Science and Technology
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• v.3 no.3
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• pp.95-115
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• 2012

Although indium (In) is not an abundant element, the use of indium is expected to grow, especially as applied to copper-indium-(gallium)-selenide (CI(G)S) solar cells. In future when CIGS solar cells will be used extensively, the available amount of indium could be a limiting factor, unless a synthetic technique of efficiently utilizing the element is developed. Current vacuum techniques inherently produce a significant loss of In during the synthetic process, while electrodeposition exploits nearly 100% of the In, with little loss of the material. Thus, an electrochemical process will be the method of choice to produce alloys of In once the proper conditions are designed. In this review, we examine the electrochemical processes of electrodeposition in the synthesis of indium alloys. We focus on the conditions under which alloys are electrodeposited and on the factors that can affect the composition or properties of alloys. The knowledge is to facilitate the development of electrochemical means of efficiently using this relatively rare element to synthesize valuable materials, for applications such as solar cells and light-emitting devices.

• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.291-295
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• 1997

Some sensory properties of synthetic sweeteners are limiting factors for use in low calorie foods of soft drinks. By combining synthetic sweeteners(Neohesperidin dihydrochacone(NHDC), stevioside) with sucrose, sorbitol or xylitol, these limitations can be overcome. Using trained taste panelists and magnitude estimation methods, synergistic effects were investigated in binary sweetener mixtures, The results showed that synergism, as much as 28% to 69%,was noted at all concentration in xylitol-stevioside, NHDC-stevioside mixtures. Synergistic effects were found only at high concentration levels in mixtures of sucrose-NHDC, sucrose-stevioside, and sorbitol-stevioside, ranging from 11% to 22%.By taking advantage of synergistic effects, ginseng tea and orange flavored beverages, sweetened with either xylitol-stevioside of NHDC-stevioside, were prepared and the sensory quality was compared with that of sucrose containing beverages. It was found that sensory characteristics were judged to be very similar for all formulations. The result suggests the possibility of using of using these sweetener mixtures as sugar substitutes in ginseng tea and orange drink.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.7
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• pp.2356-2366
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• 1996

High-power electronic chips have been advanced to such an extent that the heat dissipation capability of a system design has become one of the primary limiting factors. Therefore, thermal design must be considered in the early stage of the electronic system development. In present paper, the results of an experimental study on the forced convection cooling are presented to evaluate cooling performance of an electronic cabinet which in generally used for telecommunication system. Temperatures and thermal resistances are applied to compare the heat transfer characteristics for various locations of a fan unit as well as various configuration of non-uniform powering modules. As a result, the optimal configuration of a fan unit and powering configuration is suggested for the effective thermal design of telecommunication system.