• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.1300-1303
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• 1996

In this paper a typical problem is examined that a light, general aviation airplane, such as Cessna or Navion, in gliding turn flight shows helical-dive phenomenon when pilots try to stop the descent by using elevator only. It is known from pilot's experience that in a certain flight trim it is impossible to recover from helical-dive by using elevator only. From this study it is shown that helical-dive phenomenon is involved with longitudinal/lateral dynamics coupling to airplane's aerodynamics. Also this phenomenon consists of three parts of flight dynamics; first of all, fast longitudinal motion occurs, then is followed by a little slow lateral motion, and finally logitudinal/lateral coupled motion is fully developed.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.1429-1434
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• 2003

A number of dust particles are intruded into ODD(Optical disk drive) due to the flow caused by disk rotation and are adhered to a lens or disk surface. The space between the disk and the lens is being reduced. Someone indicates the problems of this drive that are relatively small data storing capacity and slow access time. In recent, the problems of this optical disk drive mentioned above are being solved by adding the speed of the disk's revolution, making the actuator high-speed or light, and making the beam spot size smaller than making the space narrow between disk and lens. These particle contamination affects seriously RF Signal, readout signal in an ODD. Especially, the affected parts by a particle contamination in an ODD's readout signal are objective lens and media.

• The Journal of the Korea Contents Association
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• v.8 no.11
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• pp.49-56
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• 2008

Most games based on PCs or consoles at present show vivid special effects and brilliance sceneries. However, the other games running on mobiles and portable devices can not show magnificent scenes because of low hardware specifications such as slow CPU, old graphics card and battery capacity. These games relatively prefer light and casual contents that do not need tremendous calculation. It is very important to keep minimum of game graphics quality in those games. Thus this research presents the new possibility of variable indexed color palettes to overcome the low hardware capacities.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.353-353
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• 2000

To control a light weight flexible manipulator, a composite fuzzy controller is proposed. The controller is designed based on two time scaled models. A singular perturbation technique is applied for deriving the models. The proposed controller, however, does not use the complex equilibrium manifold equations, which are usually needed in the controller based on the two time scaled models. The controller for a slow sub-model and a fast sub-model are T-S type fuzzy controllers, which use 3 linguistic variables for each sub-model. A step trajectory is used in simulations as a reference trajectory of joint motions. The results of simulations with the proposed controller show excellent damping of flexible motions compared to a controller with derivative control of flexible motions.

• Journal of the Korean Chemical Society
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• v.6 no.1
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• pp.69-72
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• 1962

Spectrophotometric studies have been made on the solutions of elementary iodine in pyridine and quinoline, in the absence of light. The results shown that triiodide ion is produced in both solutions with different rates, and that triiodide ion behaves differently in both solutions. Iodine reacts slowly with pyridine, giving rise to triiodide ion, which is relatively stable in this solvent, hereas, iodine reacts rapidly with quinoline, forming triiodide ion, which interacts further with the medium at slow rate. It has been thought that the difference of the behavior of triiodide ion in both solutions may be due to the stronger basicity of quinoline than pyridine.

• ETRI Journal
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• v.39 no.5
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• pp.632-642
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• 2017

Digital all-optical parallel computing is an important research direction and spans conventional devices and convergent nano-optics deployments. Optical bus-based interconnects provide interesting aspects such as relative information communication speed-up or slow-down between optical signals. This aspect is harnessed in the newly proposed All-Optical Linear Array with a Reconfigurable Pipelined Bus System (OLARPBS) model. However, the physical realization of such communication interconnects needs to be considered. This paper considers spatial layouts of processing elements along with the optical bus light paths that are necessary to realize the corresponding interconnection requirements. A metric in terms of the degree of required physical constraint is developed to characterize the variety of possible solutions. Simple algorithms that determine spatial layouts are given. It is shown that certain communication interconnection structures have associated intrinsic topologies.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.131-134
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• 2008

Most games based on PCs or consoles at present show vivid special effects and brilliance sceneries. However, the other games running on mobiles and portable devices can not show magnificent scenes because of low hardware specifications such as slow CPU, old graphics card and battery capacity. These games relatively prefer light and casual contents that do not need tremendous calculation. It is very important to keep minimum of game graphics quality in those games. Thus this research presents that the new possibility of variable indexed color palettes to overcome the low hardware capacities.

• Biomolecules & Therapeutics
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• v.17 no.2
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• pp.113-124
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• 2009

Aging is a multifaceted biological process that affects all organs and organ systems of the body. This review provides an up-to-date analysis of this highly exciting, rapidly changing field of science. The aging process is largely under genetic control but is highly responsive to diverse environmental influences. The genes that control aging are those that are involved with cell maintenance, cell damage and repair. The environmental factors that accelerate aging are those that influence either damage of cellular macromolecules, or interfere with their repair. Prominent among these are chronic inflammation, chronic infection, some metallic chemicals, ultraviolet light, and others that heighten oxidative stress. Other environment factors slow the aging process. Included among these agents are resveratrol and vitamin D. In addition, dietary restriction and exercise have been found to extend human lifespan. The various mechanisms whereby all these agents exert their influence on aging include epigenetic modification, chromatin maintenance, protection of telomeres, and anti-oxidant defense, among others. The complex process of aging remains under continued, intense investigation.

• Journal of Korea Foundry Society
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• v.40 no.5
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• pp.129-133
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• 2020

The outcomes of solution annealing and stress corrosion cracking in cold-worked 316L austenitic stainless steel have been studied using x-ray diffraction (XRD) and the slow strain rate test (SSRT) technique. The good compatibility with a high-temperature water environment allows 316L austenitic stainless steel to be widely adopted as an internal structural material in light water reactors. However, stress corrosion cracking (SCC) has recently been highlighted in the stainless steels used in commercial pressurized water reactor (PWR) plants. In this paper, SCC and inter granular cracking (IGC) are discussed on the basis of solution annealing in a chloride environment. It was found that the martensitic contents of cold-worked 316L stainless steel decreased as the solution annealing time was increased at a high temperature. Moreover, mode of SCC was closely related to use of a chloride environment. The results here provide evidence of the vital role of a chloride environment during the SCC of cold-worked 316L.

• Journal of the Korean institute of surface engineering
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• v.52 no.1
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• pp.1-5
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• 2019

Anodic oxidized $TiO_2$ nanotube arrays are promising materials for application in photoelectrochemical solar cells as the photoanode, because of their attractive properties including slow electron recombination rate, superior light scattering, and smooth electrolyte diffusion. However, because of the opacity of these nanotube electrodes, the back-side illumination is inevitable for the application in solar cells. Therefore, for the fabrication of solar cells with the anodic oxidized nanotube electrodes, it is required to develop efficient and transparent counter electrodes. Here, we demonstrate quantum dot-sensitized solar cells (QDSCs) based on the nanotube photoanode and transparent counter electrodes. The transparent counter electrodes based on Pt electrocatalysts were prepared by a simple thermal decomposition methods. The photovoltaic performances of QDSCs with nanotube photoanode were tested and optimized depending on the concentration of Pt precursor solutions for the preparation of counter electrodes.