• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.5 s.153
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• pp.733-741
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• 2006

This study was to investigate categories of valuation and make the standard on developing valuation of natural dyes by Delphi method. The three-round Delphi tests were performed with 36 professional in the academic, the industrial, and the art field.'Dyeability property' meant levelling, adsorption, color diversity with mordant, color stability, 'marketability', possibility of mass production, economical efficiency, functionality, demand and supply of natural dyes, 'color', yield, beautiful color, value of color and 'color fastness', washing, perspiration and light fastness. Indigo, persimmon, cochineal, safflower and onion in dyeability property were evaluated highly, functional natural dyes in marketability, red and purple color ones except indigo in color and ones containing tannin in color fastness.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.5
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• pp.73-78
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• 2004

The liquid phase LPG injection (LPLi) system (the third generation technology) has been considered as one of the next generation fuel supply systems for LPG vehicles, since it has a very strong potential to accomplish the higher power, higher efficiency, and lower emission characteristics than the mixer type(the second generation technology) fuel supply system. To investigate the durability property of core part of injector in liquid phase LPG injection system, leakage test, SEM test of injectors and analysis of unvaporized fuel components with various LPG fuel qualities were tested. The experimental results showed that no serious problem in durability test using favorable LPG fuel quality, while high leakage amount due to the large scratches in the needle and nozzle of the injector were found using LPG fuel with highly containing olefin components, especially butadiene species.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.7
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• pp.1515-1522
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• 1997

Several image coding algorithms have been developed for the telecommunication and multimedia systems with high image quality and high compression ratio. In order to achieve low entropy and distortion, the system should pay great cost of computation time and memory. In this paper, the uniform cubic lattice is chosen for Lattice Vector Quantization (LVQ) because of its generic simplicity. As a transform coding, the Discrete Wavelet Transform (DWT) is applied to the images because of its multiresolution property. The proposed algorithm is basically composed of the biorthogonal DWT and the uniform cubic LVQ. The multiresolution property of the DWT is actively used to optimize the entropy and the distortion on the basis of the distortion-rate function. The vector codebooks are also designed to be optimal at each subimage which is analyzed by the biorthogonal DWT. For compression efficiency, the vector codebook has different dimension depending on the variance of subimage. The simulation results show that the performance of the proposed coding mdthod is superior to the others in terms of the computation complexity and the PSNR in the range of entropy below 0.25 bpp.

• Structural Engineering and Mechanics
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• v.15 no.5
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• pp.535-550
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• 2003

In this paper, a boundary-type meshfree method, the boundary radial point interpolation method (BRPIM), is presented for solving boundary value problems of two-dimensional solid mechanics. In the BRPIM, the boundary of a problem domain is represented by a set of properly scattered nodes. A technique is proposed to construct shape functions using radial functions as basis functions. The shape functions so formulated are proven to possess both delta function property and partitions of unity property. Boundary conditions can be easily implemented as in the conventional Boundary Element Method (BEM). The Boundary Integral Equation (BIE) for 2-D elastostatics is discretized using the radial basis point interpolation. Some important parameters on the performance of the BRPIM are investigated thoroughly. Validity and efficiency of the present BRPIM are demonstrated through a number of numerical examples.

• 한국기계연구소 소보
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• s.19
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• pp.93-115
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• 1989

Cerebellar Model Arithmetic Controller(CMAC) has been introduced as an adaptive control function generator. CMAC computes control functions referring to a distributed memory table storing functional values rather than by solving equations analytically or numerically. CMAC has a unique mapping structure as a coarse coding and supervisory delta-rule learning property. In this paper, learning aspects and a convergence of the CMAC were investigated. The efficient training algorithms were developed to overcome the limitations caused by the conventional maximum error correction training and to eliminate the accumulated learning error caused by a sequential node training. A nonlinear function generator and a motion generator for a two d. o. f. manipulator were simulated. The efficiency of the various learning algorithms was demonstrated through the cpu time used and the convergence of the rms and maximum errors accumulated during a learning process; A generalization property and a learning effect due to the various gains were simulated. A uniform quantizing method was applied to cope with various ranges of input variables efficiently.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.5
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• pp.567-574
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• 2007

Aluminum and aluminum alloys have high rate of lightness, recycling property and excellent specific strength. Fields using them have been widening because they ould satisfy both energy reduction and high efficiency in manufactures production. But they have many problems on welding due to high thermal conductivity and reflectivity, so the study to solve these problems ate proceeding actively around the world. This study was purposed to improve weldability and spread application range for aluminium alloys by using the unique property of aluminium which absorb high energy around $800{\mu}m$ wavelength and the higher temperature, the mote absorbtion of laser beam on preheating by multi-wavelength laser beam(pulsed Nd:YAG laser + diode laser with $808{\mu}m$ wavelength). The favorable mechanical properties were acquired by the test results of strength, hardness and leak of weld metal which had reduced its defect like crack and so on.

• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.128-132
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• 2013

L-Arginine semi-oxalate (LASO) single crystal has been grown by solution growth technique at room temperature. The crystal structure and lattice parameters were determined for the grown crystal by single crystal X-ray diffraction studies. Photoluminescence studies confirm the violet fluorescence emission peak at 395 nm. Optical constants like band gap, refractive index, reflectance, extinction coefficient and electric susceptibility were determined from UV-VIS-NIR spectrum. The dielectric constant, dielectric loss and ac conductivity of the compound were calculated at different temperatures and frequencies to analyze the electrical properties. The solid state parameters such as plasma energy, Penn gap, Fermi energy and polarizability were calculated to analyze second harmonic generation (SHG). Nonlinear optical property was discussed to confirm the SHG efficiency of the grown crystal.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.5
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• pp.1035-1040
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• 2009

We propose a new encoder/decoders based on an tune able wavelength converter(TWC) and an arrayed waveguide grating(AWG) router for large capacity optical CDMA networks. The proposed encoder/decoder treats codewords of wavelength/time 2-D code simultaneously using the dynamic code allocation property of the TWC and the cyclic property of the AWG router, and multiple subscribers can share the encoder/decoder in networks. Feasibility of the structure of the proposed encoder/decoder for dynamic code allocation is tested through simulations using two wavelength/time 2-D codes, which are the generalized multi-wavelength prime code(GMWPC) and the generalized multi-wavelength Reed-Solomon code(GMWRSC). Test results show that the proposed encoder/decoder can increase the channel efficiency not only by increasing the number of simultaneous users without any multiple-access interference but by using a relatively short length CDMA codes.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.296-299
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• 2001

Data on the oil spill recovery from the water surface by light floating electromagnetic plants using a new magnetic adsorbent are given. The feasibility scope for further oil recovery from such gathered mixtures(oil+adsorbent), reuse of this magnetic adsorbent and its properly reclaiming and recycling were shown. The basic conception of the oil spill recovery and efficiency of this method were set forth.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.572-573
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• 2005

Discharge of the flat lamp lighting source research are requested very much. For improving brightness. life time. efficiency of flat lamp and plasma diagnosis of the flat lamp lighting source to understand property of lighting source is very important. When a distance of discharge electrode is 5.5mm and width is 16.5mm. we measured electron temperature and electron density measured with single Langmuir probe in flat lamp. We tested the discharge from 100 Torr to 300 Torr pressure. The pulse type was rectangular with frequency 20kHz and duty ratio was 20%. In result. electron temperature decreases and electron density increased as increase the gas pressure and electron temperature decreases and electron density increase as increase the voltage.