• Journal of Korean Society for Atmospheric Environment
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• v.17 no.1
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• pp.51-56
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• 2001

This study was carried out to interpret mathematically hydraulic behaviour in packing tower which packed 50 mm plastic Hiflow-ring with a dimension of 300 mm wide and 1,400 mm high. In view of energy saving, the recent packing. 50 mm plastic Higlow-ring was superior to conventional packings because of low pressure drop in high loads. As relative error between numerically predicted and experimentally obtained values was less then 6% in the loading and flooding point, it found that therir results appeared to be adequate. Comparison of hose two values in both dry and wet packing conditions. relative errors amount to 3.96 and 5.6%, respectively. In order to evaluate the operating characteristics of packing, the type, size, and material for packings must be estimated in various system and loads. This study is able to calculated pressure drop, hold-up, gas and liquid loads using mathematical interpretation. For these calculation, the specific constants of each packings must be calculated first all. The method of mathematical interpretation in this study turned out to be superior to the existing methods because of reduced errors at loading and flooding point.

• The Mathematical Education
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• v.48 no.4
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• pp.443-454
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• 2009

This study reviewed the notion and strategies of mathematical creativity from two point of view, mathematics and creativity. By these reviews, the spectrum was presented as frame of mathematical creativity task. Creativity and mathematics were seen as polar opposites and mathematical creativity task fit clearly at various points in this spectrum. Some focused on the quantity of ideas and originality from creative point of view. On the other hand, some focused on reasoning, insight, and generalization from mathematical point of view. The tasks on the spectrum were served as the vehicle of mathematical creativity and mathematics classroom. Therefore, there were some specific suggestions that mathematics classroom could be made a place where students and teachers would be able to foster their mathematical creativity.

• Journal of Pharmacopuncture
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• v.13 no.1
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• pp.87-92
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• 2010

Objectives:This study was performed to examine the side effect of inflammatory reactions of Pharmacopuncture lubricants (CF and JsD) using animal model. Methods:Pharmacopuncture lubricants (CF and JsD) were treated repeatedly the same point in Sprague-Dawley rats. And after finish the treatment, we obtain the tissue of muscle layer in rats where Pharmacopuncture lubricants were treated. And we observed the tissue how the change occurred in HE staining. Results: 1. There was no evidence to make inflammation induced by pharmacopuncture lubricants except 4 weeks treated group. 2. Only 4 weeks treated group(CF, JsD) were showed some infectional tissue's view in H-E staining. But it is not certain due to Pharmacopuncture lubricants. Conclusion:It appears that prolonged usage of pharmacopuncture lubricant on the specific point can induce inflammation, so we may be careful for treating time and point using pharmacopuncture lubricant in clinics.

• Journal of Mechanical Science and Technology
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• v.17 no.11
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• pp.1756-1766
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• 2003

Numerical modeling is carried out to investigate forced convective heat transfer to near-critical water in developing laminar flow through a circular tube. Due to large variations of thermo-physical properties such as density, specific heat, viscosity, and thermal conductivity near thermodynamic critical point, heat transfer characteristics show quite different behavior compared with pure forced convection. With flow acceleration along the tube unusual behavior of heat transfer coefficient and friction factor occurs when the fluid enthalpy passes through pseudocritical point of pressure in the tube. There is also a transition behavior from liquid-like phase to gas-like phase in the developing region. Numerical results with constant heat flux boundary conditions are obtained for reduced pressures from 1.09 to 1.99. Graphical results for velocity, temperature, and heat transfer coefficient with Stanton number are presented and analyzed.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.4
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• pp.290-298
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• 2013

Geomagnetic is refracted by building's wall and pillar. Therefore refracted geomagnetic is able to be used as feature point. In a specific space, a mobile device that is equipped with magnetic sensor array measures 3-axis magnetic field for each point. Magnetic field map is acquired by collecting the every sample point in the magnetic field. The measured magnetic field must be calibrated, because each magnetic sensor has a distortion. For this reason, sensor distortion model and sensor calibration method are proposed in this paper. Magnetic field that is measured by mobile device matches magnetic field map. Result of the matching is used for position estimation. This paper implements hardware system for position estimation method using magnetic field map.

• Journal of Electrochemical Science and Technology
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• v.9 no.2
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• pp.149-156
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• 2018

In this technical note, I report the analysis of electrochemical impedance data measured with potential sweeping. Even though the instruments for voltammetric impedance measurements have been developed for decades using different approaches, their applications are limited due to the lack of well-established protocols to easily analyze voltammetry data. To fill this gap, the singular point of the specific potential is considered that is only determined by the standard/formal potential and the transfer coefficient and is independent of the kinetics and experimental parameters (including revertability) of faradaic reactions. Taking the advantage of its inertness, I suggest an approach employing the singular point as a reference to obtain general electrochemical information. As all the concepts and methods are verified with numerical simulations, this technique is expected to be applied for complex reactions involving electrochemical and chemical reaction mechanisms.

• Journal of the military operations research society of Korea
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• v.30 no.2
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• pp.133-140
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• 2004

In this paper, with the limited range of ammunition supply point(ASP) at ammunition battalion in specific corps and light automobile battalion(LAB) directly supports its vehicle for ammunition supply, we propose optimal model to minimize transportation time and logistics cost using integer programming(IP) for efficient ammunition resupply allocation during a given operation period of front combat unit. And then, we consider ammunition treatment and supply capacity of ammunition supply point(ASP), constraint elements of transportation ability considering time and cost, ammunition storage capacity of combat unit, combat situation and unit mission to propose this model. Finally, through numerical example, we examine the applicable feasibility of proposed model.

• Advances in Energy Research
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• v.8 no.3
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• pp.185-202
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• 2022

This research work focuses to design and simulate a 200W solar power system with electrical power conservation scheme as well as thermal power conservation modeling to improve power extraction from solar power plant. Many researchers have been already designed and developed different methods to extract maximum power while there were very researches are available on improving solar power thermally and mechanically. Thermal parameters are also important while discussing about maximizing power extraction of any power plant. A specific type of coolant which have very high boiling point is proposed to be use at the bottom surface of solar panel to reduce the temperature of panel in summer. A comparison between different maximum power point tracking (MPPT) technique and proposed MPPT technique is performed. Using this proposed Thermo-electrical MPPT (TE-MPPT) with Deep Learning Algorithm model 40% power is conserved as compared to traditional solar power system models.

• Journal of the Korean Society of Costume
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• v.56 no.4 s.103
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• pp.48-64
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• 2006

The purpose of the study was to demonstrate how to recreate spencer jacket in the empire style in an attempt to apply this historic style to theatrical costumes and other high fashion items in modern times. The study was carried out through 2 steps. (1)Block patterns of spencer jacket of its basic design were developed through draping based on the design characteristics mentioned above. (2)Spencer jackets of three designs, which were the typical designs of each category have been made of velvet to find out more specific structural characteristics. The structural characteristics of Spencer jacket in draping were as follows: (1)Jacket length position was suitable 9cm below body's bust line and neckline should be enlarged front & side neck point 2cm, back neck point 1.5cm. (2)Cut out the front bodice after CF line moved 1cm outwards and bust dart amount should not exceed 2-3cm. Shoulder point moved inwards. (3)Side back grain line was parallel to princess line of the back bodice. Add 0.5cm ease to the under arm of the front and side bark bodice, it was good for the activity of arm. (4)Armhole line was trued as maintaining to across back width 14-15cm at least. Shoulder line was to connect from the point 2cm depart shoulder point along armhole line to point 2cm side neck point along neck line. (5)Sleeve length was suitable 70cm, cut out the bias direction to move forwards the grain line from shoulder point. Puff position was good from the 2cm depart shoulder point to shoulder line.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1259-1263
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• 2004

This paper describes position estimation algorithm using neural network for the navigation of the vision-based wheeled mobile robot (WMR) in a corridor with taking ceiling lamps as landmark. From images of a corridor the lamp's line on the ceiling in corridor has a specific slope to the lateral position of the WMR. The vanishing point produced by the lamp's line also has a specific position to the orientation of WMR. The ceiling lamps have a limited size and shape like a circle in image. Simple image processing algorithms are used to extract lamps from the corridor image. Then the lamp's line and vanishing point's position are defined and calculated at known position of WMR in a corridor. To estimate the lateral position and orientation of WMR from an image, the relationship between the position of WMR and the features of ceiling lamps have to be defined. But it is hard because of nonlinearity. Therefore, data set between position of WMR and features of lamps are configured. Neural network are composed and learned with data set. Back propagation algorithm(BPN) is used for learning. And it is applied in navigation of WMR in a corridor.