• Journal of the Korea Society for Simulation
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• v.10 no.2
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• pp.1-14
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• 2001

The layout design of component plays an important role in the design and usability of many engineering products. The Engineering artifacts of today are becoming increasingly complicated. The simulated annealing method has been applied effectively to the layout and packing problems of wafer. The main characteristics of simulated annealing method is that an optimum can be obtained from the many local optimums by controlling the temperature and introducing the statistic flickering. The objective of this study is to suggest a method to apply the simulated annealing method to the three dimensional layout design of submergible boat which has multiple constraint conditions and evaluation criteria. We describe an approach to define cost function, constraints and generate layouts using a computer. In this research three dimensional LAYout Design Optimization Program(LAYDOP ver.2) has been developed. The layout result(the total value of evaluation criteria) designed by a human layout expert has been improved by 31.0% using this program.

• YAKHAK HOEJI
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• v.20 no.1
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• pp.63-69
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• 1976

Prednisolone tablet product design problem was structured as constrained optimization problem and subsequently solved by multiple regression analysis and Lagrangian method of optimixation. Prednisolone was the drug chosen and anhydrous lactose and corn starch were the adjuvants. The effect of anhydrous lactose and corn starch concentrations on tablet hardness, volume, disintegration time and in vitro release rate was studied. The concentrations of anhydrous lactose and corn starch used in this experiment were 30-60 percent and 5-30 percent, respectively. A full second-order (quadratic) model with all possible two-factor interactions was employed. To obtain the values of anhydrous lactose and corn starch which miniumize the in vitro : release time (t$_{60%}$) subject to the constraint on tablet hardness, disintegration time and volume, we solved the Lagrange function. Multiple correlation coefficients for the regression models were correlated at less than 0.05 level and it was found that the optimum concentrations of anhydrous lactose and corn starch were 45 percent and 21 percent, respectively.

• Journal of Navigation and Port Research
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• v.28 no.2
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• pp.129-133
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• 2004

Column subtraction, originally proposed by Harche and Thompson(1994), is an exact method for solving large set covering, packing and partitioning problems. Since the constraint set of ship scheduling problem(SSP) have a special structure, most instances of SSP can be solved by LP relaxation This paper aim, at applying the column subtraction method to solve SSP which am not be solved by LP relaxation For remained instances of unsolvable ones, we subtract columns from the finale simplex table to get another integer solution in an iterative manner. Computational results having up to 10,000 0-1 variables show better performance of the column subtraction method solving the remained instances of SSP than complex branch and-bound algorithm by LINDO.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.77-83
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• 2012

In this paper, a low-complexity embedded compression (EC) Codec algorithm for the wavelet video coder is applied to reduce excessive external memory requirements. The EC algorithm is used to achieve a fixed compression ratio of 50 % under the near-lossless-compression constraint. The EC technique can reduce the 50 % memory requirement for intermediate low-frequency coefficients during multiple discrete wavelet transform stages compared with direct implementation of the wavelet video encoder of this paper. Furthermore, the EC scheme based on a forward adaptive quantization and fixed length coding can save bandwidth and size of buffer between DWT and SPIHT to 50 %. Simulation results show that our EC algorithm present only PSNR degradation of 0.179 and 0.162 dB in average when the target bit-rate of the video coder are 1 and 0.5 bpp, respectively.

• Journal of the Korean Geotechnical Society
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• v.15 no.5
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• pp.65-80
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• 1999

This paper shows the results of a series of model tests on the behavior of single flexible pile, which is subjected to lateral load, in non-homogeneous Nak-Dong River sands, consisting of two layers. The purpose of the present paper is to investigate the effects of ratio of lower layer thickness to embedded pile length, ratio of soil modulus of upper layer to lower one, and pile head constraint condition on the characteristics of lateral behavior of single pile. These effects can be quantified only by the results of model tests. Based on the results of model tests, in non-homogeneous sand, it was found that the lateral behavior depends upon the ratio of soil modulus of upper layer to lower one. And, in respect of deflection, it was found that the relationship between the deflection ratio of non-homogeneous to homogeneous sand and the ratio of lower layer thickness to embedded pile length can be fitted to exponential function of H/L and lateral load by model tests results. Also, in respect of maximum bending moment, it was found that the relationship H/L and $MBM_{fixed-head}/MBM_{free-head}$ can be fitted to linear function of H/L by model test results.

• Journal of the Korean Electrochemical Society
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• v.9 no.1
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• pp.34-39
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• 2006

Electrochemical properties of Cu foil current collector with a $Li_{0.5}La_{0.5}TiO_3$ Cu a Si thin film deposited by r.f sputtering as an anode for Li free battery were evaluated. The Cu foil current collectors were lied in and out of plasma during sputtering process. The X-ray diffraction results indicated that the as-deposited Si and $Li_{0.5}La_{0.5}TiO_3$ thin films in and out of plasma did not show any crystalline difference. The $Li_{0.5}La_{0.5}TiO_3$ film in plasma and Si film out of plasma showed better cyclability since crystalline $Li_{0.5}La_{0.5}TiO_3$ has much higher ionic conductivity and crystalline Si film is much sensitive far volume change during charge-discharge process. These results suggested that the deposition of amorphous Si on Cu foil current collector is much better for fabrication of Li free battery and it can be useful for the unique battery with a cycling number constraint of below 10.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.58-70
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• 2002

In an attempt to compare the antioxidation effects of constrain the oxidation and improve the structural stability, retinol and various antioxidants were together encapsulated by liposome. Four water soluble and four oil soluble antioxidants were tested for performance. The influence of tertiary butylhydroquinone(TBHQ), ${\alpha}$-glycosyl rutin(${\alpha}$-G rutin), licorece, pycnogenol as water soluble antioxidants and butylated hydroxytoluene(BHT), ${\alpha}$-lipoic acid, ferulic acid, natural concentrated tooopherol(no-tocopherol) as oil soluble antioxidants on the constraint of oxidation of retinol were investigated. Additional study was conducted to compare the synergic effect of antioxidation for retinol with licorice, pycnogenol, ${\alpha}$-lipoic acid and BHT. All the antioxidant used at the study constrained oxidation of retinol. The effect of antioxidation for retinol increased in order of licorice, pycnogenol, TBHQ, ${\alpha}$-G rutin as water soluble antioxidants and ${\alpha}$-lipoic acid, BHT, no-tocopherol, ferulic acid as oil soluble antioxidants. In conclusion, ${\alpha}$-lipoic acid is more effective retinol antioxidants than BHT. And the combination of ${\alpha}$-lipoic acid and BHT gave best synergic among six combinations.

• Progress in Medical Physics
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• v.13 no.1
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• pp.32-36
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• 2002

For Intensity Modulated Radiation Therapy(IMRT), the spatial resolution of intensity map(IM) is limited by the width of multi-leaf collimator, which would make an effect on the conformity of the target, as well as organs at risk. Several Methods are suggested to increase the spatial resolution, which can be categorized by the hardware-dependent technique and the software-based technique. However the best solution might be to make the width of MLC finer. it has several obstacles in the respects of technical difficulty and cost. This preliminary study is designed to investigate the clinical effectiveness of the virtual-micro IMRT(VMIMRT) technique, one of the software-based technique. A particular intensity map was created, which has 42$\times$54 pixel dimension ,0.5cm pixel size and 15 intensity levels. Using this intensity map, segment fields of IMRT were generated with 1$\times$lcm, 0.5$\times$1cm, 0.5$\times$0.5cm(VMIM) beamlet size, respectively As results, we found that there was no evidence of improvement for VMIMRT, compared with the 0.5$\times$lcm beamlet size which can be delivered by 1cm width MLC. The reason seems to be due to the constraint of VMIMRT. Further study is required to prove the benefit of the VIMRT in clinical case like head and neck cancer, where is expected that higher resolution than 1cm is necessary.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.11
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• pp.88-96
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• 1994

This paper proposes a new vector quantization scheme which exploits high correlations among indexes in vector quantization. An optimal vector quantizer in the rate-distortion sense can be obtained, if it is designed so that the average distortion can be minimized under the constraint of the conditional entropy of indes, which is usually much smaller than the entropy of index due to the high correlations among indexes of neighboring vectors. The oprimization process is very similar to that in ECVQ(entropy-constrained vector quanization) except that in the proposed scheme the Viterbi algorithm is introduced to find the optimal index sequence. Simulations show that at the same bitrate the proposed method provides higher PSNR by 1.0~3.0 dB than the conventional ECVQ when applied to image coding.

• Explosives and Blasting
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• v.34 no.4
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• pp.40-45
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• 2016

Sites, where explosives are used, are constantly under constraint of vibration and noise levels. If a sensitive area is located nearby the sites, mechanical excavation has been preferred rather than blasting. Recently, however, blasting using electronic detonators is applicable in the areas, where previously should be excavated by mechanical methods. $HiTRONIC^{TM}$ is a fourth-generation detonator that utilizes Hanwha Corporation's advanced electronic technology. The detonator contains IC-Chip, which allows delay times between 0~15,000ms with 1ms interval. Furthermore, the product can provide high accuracy(0.01%) for accurate-blasting. Electronic detonator is widely used in highway and railway construction sites, large limestone quarries, and other works. In this paper, several sites, in which HiTRONIC was used, are introduced in order to enhance understanding of electronic detonator.