• Journal of the Korean Society of Propulsion Engineers
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• v.20 no.3
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• pp.17-24
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• 2016

The reacting flows of gaseous hydrogen/liquid oxygen 2D coaxial shear injector with varying recess length are numerically analyzed. The standard ${\kappa}-e$ model and laminar flamelet model are adopted for the steady turbulent combustion with the ideal and real gas equations. As the recess length increases, the recirculating region in the combustion chamber expands and the vorticity is intensified. Also, the variations of temperature, products, and pressure are strongly related to the recess length. The results show that an efficient combustor can be obtained by the introduction of the recessed injector.

• Journal of Satellite, Information and Communications
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• v.10 no.4
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• pp.71-76
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• 2015

In this paper, we propose a system model which effectively transmits the data and conducts RF energy harvesting in a wireless communication network of LTE and 5G. Through time switching and power splitting schemes, we find a time & power ratio to show the good performance according to the standard that we set up for transmitting a signal and conducting RF energy harvesting. So selecting optimal time & power ratio, we can efficiently transfer data to other drones and harvest the amount of harvested power simultaneously we desire. Also, according to conducting the performance analysis, we can compare an ideal receiver with the proposed system model. And, we suggest a future direction of research.

• Advances in robotics research
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• v.1 no.1
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• pp.81-99
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• 2014

This paper contributes towards the development of a computer vision system for telemonitoring of industrial articulated robotic arms. The system aims to provide precision real time measurements of the joint angles by employing low cost cameras and visual markers on the body of the robot. To achieve this, a mathematical model that connects image features and joint angles was developed covering rotation of a single joint whose axis is parallel to the visual projection plane. The feature that is examined during image processing is the varying area of given circular target placed on the body of the robot, as registered by the camera during rotation of the arm. In order to distinguish between rotation directions four targets were used placed every $90^{\circ}$ and observed by two cameras at suitable angular distances. The results were deemed acceptable considering camera cost and lighting conditions of the workspace. A computational error analysis explored how deviations from the ideal camera positions affect the measurements and led to appropriate correction. The method is deemed to be extensible to multiple joint motion of a known kinematic chain.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.5
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• pp.1139-1145
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• 2021

This study is aimed at developing a measurement instrument for the superior product development program of Deli Serdang cassava, Indonesia. This research population is the target population of Deli Serdang Micro, Small and Medium-sized Enterprises (MSMEs) which produces cassava. The sample was randomly selected and consisted of 300 MSMEs. The study method is research and development with confirmatory factor analysis using Amos software. The data collection technique was a questionnaire. Study results used the maximum likelihood method which showed that the validity and reliability instruments met the ideal loading factor value > 0.5 and a significance value of p (0.000). The model built also meets the fit criteria based on the Goodness of Fit Model Standard. All instruments are presented to build and measure the superior cassava product development program by Deli Serdang MSMEs. This superior product development program comprises (1) economic contribution (with a loading factor value of 0.76) (2) social aspects (with a loading factor value of 0.76) (3) cultural aspects (with a loading factor value of 0.99) and (4) institutional (with a loading factor value of 0.87). This result means that all instruments have proven construct validity.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.3
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• pp.270-275
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• 2006

The cultivated pearls collected for the study were pretreated through the removal of contaminants and the surface bleaching for easy dyeing. Coloring of pearls are necessary after selecting dyes adsorbable to the Conchiolin layer, a kind of hard protein formed in the seawater, covering the surface of the pretreated pearls. Dyes adsorbable to the Conchiolin layers are mostly basic dyes such as Rhodamine 6G(R6G), Rhodamine B(RB), Methylene Blue(MB) etc. and the binary and ternary competitive adsorption were performed by mixing two or three dyes together. The multi-dye adsorption data were compared with the predictions from the ideal adsorbed solution theory(IASI) combined with the single-dye adsorption model, the Langmuir or the Redlich-Peterson(RP) model. The quality of prediction was compared by using determination coefficient($R^2$) and standard deviation(SSE) values. Predictions from the IAST were found to be in good agreement with the data for the R6G/RB binary adsorption to the pearl layers not fractionated with their size, except for the adsorption data for RB at high concentrations. Among the three binary adsorption systems, R6G/RB, R6G/MB, and MB/RB, only the RB sorption data in the R6G/RB binary system was in poor agreement with the IAST prediction. Competitive adsorption data in ternay systems were in good agreement with the predictions from the IAST except for the RB data.

• Structural Engineering and Mechanics
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• v.52 no.6
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• pp.1069-1084
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• 2014

The long-term performance of plates resting on viscoelastic foundations is a major concern in the analysis of soil-structure interaction. As a powerful mathematical tool, fractional calculus may address these plate-on-foundation problems. In this paper, a fractionalized Zener model is proposed to study the time-dependent behavior of a uniformly loaded rectangular thin foundation plate. By use of the viscoelastic-elastic correspondence principle and the Laplace transforms, the analytical solutions were obtained in terms of the Mittag-Leffler function. Through the analysis of a numerical example, the calculated plate deflection, bending moment and foundation reaction were compared to those from ideal elastic and standard viscoelastic models. It is found that the upper and lower bound solutions of the plate response estimated by the proposed model can be determined using the elastic model. Based on a parametric study, the impacts of model parameters on the long-term performance of a foundation plate were systematically investigated. The results show that the two spring stiffnesses govern the upper and lower bound solutions of the plate response. By varying the values of the fractional differential order and the coefficient of viscosity, the time-dependent behavior of a foundation plate can be accurately captured. The fractional differential order seems to be dependent on the mechanical properties of the ground soil. A sandy foundation will have a small fractional differential order while in order to simulate the creeping of clay foundation, a larger fractional differential order value is needed. The fractionalized Zener model is capable of accounting for the primary and secondary consolidation processes of the foundation soil and can be used to predict the plate performance over many decades of time.

• Earthquakes and Structures
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• v.17 no.2
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• pp.221-232
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• 2019

Material non-linearity of Reinforced Concrete (RC) framed structures is studied by modelling concrete using the Concrete Damage Plasticity (CDP) theory. The stress-strain data of concrete in compression is modelled using the Hsu model. The structures are analyzed using a finite element approach by modelling them in ABAQUS / CAE. Single bay single storey RC frames, designed according to Indian Standard (IS):456:2000 and IS:13920:2016 are considered for assessing their maximum load carrying capacity and failure behavior under the influence of gravity loads and lateral loads. It is found that the CDP model is effective in predicting the failure behaviors of RC frame structures. Under the influence of the lateral load, the structure designed according to IS:13920 had a higher load carrying capacity when compared with the structure designed according to IS:456. Ultra High Performance Fiber Reinforced Concrete (UHPFRC) strip is used for strengthening the columns and beam column joints of the RC frame individually against lateral loads. 10mm and 20mm thick strips are adopted for the numerical simulation of RC column and beam-column joint. Results obtained from the study indicated that UHPFRC with two different thickness strips acts as a very good strengthening material in increasing the load carrying capacity of columns and beam-column joint by more than 5%. UHPFRC also improved the performance of the RC frames against lateral loads with an increase of more than 3.5% with the two different strips adopted. 20 mm thick strip is found to be an ideal size to enhance the load carrying capacity of the columns and beam-column joints. Among the strengthening locations adopted in the study, column strengthening is found to be more efficient when compared with the beam column joint strengthening.

• Archives of design research
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• v.17 no.3
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• pp.39-50
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• 2004

According to the survey done among the 20s of university students in Oct. 2002, the female animation characters from Korea and Japan have almost no distinction. Speaking of the features of the characters, they have big eyes, a long nose, an oval face. However, their eyes and mouths are expressed exaggeratedly, which makes them hard to get a good impression from the people. It seems that the identity of Korean female animation characters is disappearing in terms of the copycat from western animation characters. Through the research, the features of 20s of Korean and Japanese girls are compared and they were reviewed from the ideal and biological point of view. Then, the animation characters, which physiognomy has been applied, are created based on result, which I am trying to find the standard model of Korea female animation character. As an ideal point of view, it turns out that Korean has a positive reaction on the female animation characters with the cute & introspective characteristics. On the contrary, Korean has a negative reactions on the ones that were created in a biological viewpoint and has a highly sensitive and discontented characteristics. This shows that Korean do not prefer the female animation characters with highly sensitive and discontented characters. According to the survey, 73.5% of people could find the same 7 kinds of female characters which are shown frequently in the animation. This means that the oriental physiognomy is an effective way to approach to the features of the character's face depending on the characteristics of each female characters. The characters in this study are based on real face of female, but we can create the various animation characters if we apply the partial feature of distinctive each personal face.

• The Korean Journal of Ceramics
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• v.4 no.2
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• pp.146-150
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• 1998

The total conductivity and oxygen permeation in (Ce1-xZrxO2)0.9(CaO)0.1 solid solutions were measure das a function of temperature and oxygen partial pressure. Empirically, σ at given x and T was expressed essentially by σ=σo2+σeo Po2-1/4, where σo2 and σeo are constant. Applying a standard defect model in which major defects are Cace", Cece' and Vo in ideal solution, we can assign σo2 as the oxide ion conductivity decreases while the electronic conductivity increases with the increase in Zr content. Using the oxide ion and electronic conductivities thus determined, the oxygen permeation flux was calculated for respective Po2 and T conditions at which the measurements were made. The calculated values were found to agree with the observed ones.

• Proceedings of the IEEK Conference
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• 2009.05a
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• pp.402-404
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• 2009

The development of health information technology enables people to access, view and acquire personal health record. But still, there have been a number of obstacles such as the absence of the standard to realize the ideal Personal Health Record(PHR) system. In this study, we proposed the service model that serves periodic Health Record Summary which is made by a medical specialist to people who are in the busy lives. Healthcare data from EMR in a hospital including people generate themselves at home is sent to a physician to make a medical opinion, and then it is changed into Health Level 7 Continuity of Care Document(CCD) format for interoperability. After a physician writes his opinion about patient's health condition, it will send to people by email. People who receive the health record summary data by email can save them into a USB device to view own PHR and medical comments of a physician through a computer. It will help people managing their own health condition with an opinion of a medical specialist.