• Journal of Environmental Science International
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• v.9 no.6
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• pp.489-494
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• 2000

This research focused on the priotity decision for establishment sriteria on the effects which environmental sculptures in urban area. The analysis performed in this study used the AHP(Analytic Hierarchy Process) that is recognized as a useful decision-making tool to select and evaluate alternatives through pairwise comparison in the context of hierarchical decision structure. The results obtained from the analysis drawn by collecting the professional opinions of 5 experts for environmental sculptures are as follows: 1. The orders of establish criteria priorities on environmental sculptures were harmony of environment> symbol> public> function. The harmony of environment was the most important priority because it showed the highest weight of criteria. 2. The alternative priorities of environmental sculptures were the meaning of work>setting place> social contribution> physical quality .The meaning of work showed the highest change in the weight of alternative. 3.The sensitivity analysis of environmental sculptures demonstrated that the rate of change in the alternative priorities of the public was stabilized although the criteria importance varied, while the harmony of environment, the symbol intimated and function of priorities has their rates of weight changed if the criteria priorities were high.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1194-1202
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• 2002

A study on the topology optimization of a multi-spectral camera for space-use is presented. The optimization is carried out under self-weight and polishing pressure loading. A multi-spectral camera for space-use experiences degradation of optical image in the space, which can not be detected on the optical test bench on the earth. An optical surface deformation of a primary mirror, which is a principal component of the camera system, is an important factor affecting the optical performance of the whole camera system. In this study, topology optimization of the primary mirror of the camera is presented. As an objective function, a measure of Strehl ratio is used. Total mass of the primary mirror is given as a constraint to the optimization problem. The sensitivities of the objective function and constraint are calculated by direct differentiation method. Optimization procedure is carried out by an optimality criteria method. For the light-weight primary mirror design, a three dimensional model is treated. As a preliminary example, topology optimization considering a self-weight loading is treated. In the second example, the polishing pressure is also included as a loading in the topology optimization of the mirror. Results of the optimized design topology for the mirror with various mass constraints are presented.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.5
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• pp.775-787
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• 2016

This study examined the wearing conditions of compression wear for weight training. Compression wear has recently received significant attention from the public and athletes as high-level functional sportswear. The survey was conducted on 373 men in their 20s for general information on purchase behavior, preferred brand, function, and preferred design. The majority of participants (n=181) were aware of the function of compression wear. The most selected reason for wearing compression wear was for its convenience during sports activities. Respondents had the greatest preference for designs with a round neckline, regular leggings type, upper arm-length sleeve, and thigh-length bottom. Respondents also wanted a stronger compression in the core muscle part (abdomen, back, and waist).

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.127-134
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• 2011

A genetic algorithm (GA) has been employed to optimize the major design variables of the liquid rocket engine. Pressure of the main combustion chamber, nozzle expansion ratio and O/F ratio have been selected as design variables. The target engine has the open gas generator cycle using the LO2/RP-1 propellant. The gas properties of the combustion chamber have been obtained from CEA2 and the mass has been estimated using reference data. The objective function has been set as multi-objective function with the specific impulse and thrust to weight ratio using the weight method. The result shows about 4% improvement of the specific impulse and 23% increase of the thrust to weight ratio. The Pareto frontier line has been also obtained for various thrust requirements.

• Journal of Pharmaceutical Investigation
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• v.20 no.1
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• pp.19-28
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• 1990

Pharmacokinetic parameters of aminoglycosides are dependent on renal function, sex, age, hematocrit, fever, lean body weight (LBW) and disease states, etc. Therefore, the individual pharmacokinetic parameters such as half life $(t^{1/2})$ and volume of distribution(Vd) are needed to achieve optimal therapy. However these parameters had not been determined in Koreans. The purpose of this study was to evaluate the Vd and $t^{1/2}$ of amikacin in Korean patients who had normal renal function, to compare the mean values of study group with that reported in the literature and to compare the measured $t^{1/2}$ with the expected $t^{1/2}$ based on actual body weight (ABW), LBW and ideal body weight (IBW), respectively. Based on data, the Vd was greater than the literature and $t^{1/2}$ was similar to the literature. The predicted $t^{1/2}$ based on IBW was the closest to actual $t^{1/2}$. And postpartum patients had greater Vd than other group and had lower correlation between actual elimination rate constant and calculated creatinine clearance but higher correlation between actual elimination rate constant and Vd than other group.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.182-189
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• 1993

To improve the resolution of complex flow field features, grid adaptation scheme of Anderson has been revised, which was based on the Poisson grid generator of Thompson. Anderson's original scheme adapts the grid to solution automatically, but if flow field is more or less complex, then the adaptivity is weak. So the technique of using threshold which is used in unstructured grid system is adopted. The regions of large variation in the solution are marked by marking function which has the property of total variation of the solution, and these regions have same values of weight but other regions are neglected. This updated method captures shocks clearly and sharpy. Four examples are demonstrated, (1) Hypersonic flow past a blunt body, (2) High speed inlet analysis, (3) Supersonic flow of M=1.4 over a 4% biconvex airfoil in a channel, (4) Hypersonic shock-on-shock interaction at M=8.03.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.389-394
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• 2003

In this paper, a shape optimization technique is applied to design of an air-conditioner mounting bracket. The mounting bracket is a structural component of an engine, on which bolts attach an air-conditioner compressor. The air-conditioner mounting bracket has a large portion of weight among the engine components. To reduce weight of the bracket, the shape is optimized using a finite element software. The compressor assembly, composed of a compressor and a bracket is modeled using finite elements. An objective function for the shape optimization of the bracket is the weight of the bracket. Two design constraints on the bracket are the first resonant frequency of the compressor assembly and the fatigue life of the bracket. The design variables are the shape of the bracket including thickness profiles of the front and back surfaces of the bracket, radius of outer bolt-holes, and side edge profiles. The coordinates of the FE nodes control the shape parameters. Optimal shapes of the bracket are obtained by using SOL200 of MSC/NASTRAN.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.2
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• pp.23-30
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• 2009

Recently, rotation symmetric Boolean functions have attracted attention since they are suitable for fast evaluation and show good cryptographic properties. For example, important problems in coding theory were settled by searching the desired functions in the rotation symmetric function space. Moreover, they are applied to designing fast hashing algorithms. On the other hand, for some homogeneous rotation symmetric quadratic functions of simple structure, the exact formulas for their Hamming weights and nonlinearity were found[2,8]. Very recently, more formulations were carried out for much broader class of the functions[6]. In this paper, we make a further improvement by deriving the formula for the Hamming weight of quadratic rotation symmetric functions containing linear terms.

• Journal of Environmental Science International
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• v.30 no.3
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• pp.289-293
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• 2021

This study was conducted to investigate the distribution of duck production in duck housing as a function of the breeding period. The items in duck production distribution included body weight, feed intake, feed conversion ratio, and average duck production. All data were based on eight cycles (June and December, 2017; February, June, August, September, and November, 2018; February, 2019) at Farm Site 1 through 7. The most optimal results in the duck production distribution were observed at Site 1 for weight gain, feed intake, and feed efficiency. This could be explained by the fact that Site 1 was well managed in environmental improvement and sustainability. Based on these data, selective alternatives to improve duck production in duck farms are recommended as follows: first, proper management and recording of litter used as a flooring material are required, and second, continuous management such as temperature, relative humidity and ventilation is needed. Lastly, it is necessary to change duck facilities by introducing environmental management techniques. Furthermore, efforts to improve the overall facilities and management of duck breeding farms through additional field studies are needed in the future.

• Computers and Concrete
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• v.29 no.6
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• pp.361-374
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• 2022

On the premise of ensuring that the automatic and quantitative discharging function of concrete conveyors is met, the accuracy of the weight forecast by the mathematical model of the screw conveying volume is improved, and the error of the weight of the concrete parts and the accumulation thickness is reduced. In this paper, the discrete element method (DEM) is used to simulate the macroscopic flow of concrete. Using the concrete discrete element model, the size of the screw conveyor is set, and establish the response model between the influencing factors (process and structure) and the concrete mass flow rate according to the design points of the screw discharging experiment. The nonlinear data fitting method is used to obtain the volumetric efficiency function under the influence of process and structural factors, and the traditional screw conveying volume model is improved. The mass flow rate of concrete predicted by the improved mathematical model of screw conveying volume is consistent with the test results. The model can accurately describe the conveying process of concrete and achieve the purpose of improving the accuracy of forecasting the weight of discharged concrete.