• 한국태양에너지학회:학술대회논문집
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• 2008.11a
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• pp.63-68
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• 2008

Efforts tp overcome the current challenge of global warming and abnormal temperature are being taken around the world. According to a report, average temperature of Korea has increased by about $0.8^{\circ}C$ for a century. In particular, temperature has rapidly increased since year 2000. Climate changes have brought remarkable changes in our lives. For example, agricultural field will see changes in crops and production. Energy used to maintain and manage architectures will be changed as well. In order to actively cope with rapidly changing global climate which drives changes from the basic behavior of our lives to subtle changes, international cooperation and researches are performed around the word. For instance, as a part of these global efforts, research on typical meterological data for computer simulation program to evaluate architecture energy performance is in progress in Korea. In order to conduct research on typical meterological data in format of data per time, reference regarding monthly maximum/minimum temperature time is required. Unfortunately, however, reference regarding maximum/minimum temperature time hasn't been defined in Korea. Therefore, this study aims to provide fundamental data essential for various researches by calculating maximum/minimum temperature time of major cities across Korea. According to the study, maximum temperature occurs at 3 p.m and minimum temperature occurs at 5 a.m or 6 a.m. respectively, in overall areas.

• Journal of the Korean Dietetic Association
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• v.29 no.2
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• pp.73-85
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• 2023

This study examined the nutritional information using the nutrition labels of gimbap sold at convenience stores and evaluated nutritional adequacy compared to dietary reference intakes for Korean adolescents. Thirty gimbaps (triangular gimbaps and regular gimbaps according to the main ingredients of vegetables, fish, and meat) were purchased at five convenience stores of different brands with many stores in Korea. The food and nutrition labels of the gimbaps were investigated, and nine minerals were analyzed using inductively coupled plasma-mass spectrometry (ICP-MS). The average price of gimbap was 1,906.7 won, and average energy was 292.0 kcal, and the protein content was 15.5% of the recommended intake for Korean male adolescents aged 15~18 years. The mineral content ranged from 6.9% for zinc to 39.0% for selenium. Except for sodium and selenium, the energy, protein, and mineral content did not meet 1/3 of dietary reference intakes for adolescents. For the index of nutritional quality (INQ), calcium and zinc were the lowest in the triangular and regular gimbap, respectively. The INQ of potassium was significantly higher in triangular gimbap with vegetables. The content and INQ of selenium were in regular gimbap with fish, and the zinc INQ was in regular gimbap with meat. Overall, gimbap sold in convenience stores has a high sodium content, and the contents of energy, protein, and minerals, except selenium, are insufficient for a single meal.

• Analytical Science and Technology
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• v.20 no.3
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• pp.193-197
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• 2007

In this study, the effect of metal treatment on granular activated carbon (GAC) was investigated in the context of phenol adsorption. Cobalt(II) nitrate, and zinc(II) nitrate solution were used for metal treated. The specific surface area and the pore structure were evaluated from nitrogen adsorption data at 77 K. The phenol adsorption rates onto GAC were measured by UV-Vis spectrophotometer. Iodine adsorption capacity of Co-GAC is much better then that of the GAC. The Co-GAC with mesopore is more efficient than other adsorbents for the adsorption of polymer such as methyleneblue. The adsorption capacity of reference-GAC and metal-GAC were increased in order of Co-GAC>Zn-GAC>Reference-GAC, in spite of a decrease in specific surface area which was resulted from pore blocking by metal.

• Advances in nano research
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• v.15 no.5
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• pp.385-399
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• 2023

Hexagonal boron nitride (h-BN), commonly referred to as Boron Nitride Nanoribbons (BNNRs), is an electrical insulator characterized by high thermal stability and a wide bandgap semiconductor property. This study delves into the electronic properties of two BNNR configurations: Armchair BNNRs (ABNNRs) and Zigzag BNNRs (ZBNNRs). Utilizing the nearest-neighbour tight-binding approach and numerical methods, the electronic properties of BNNRs were simulated. A simplifying assumption, the Hamiltonian matrix is used to compute the electronic properties by considering the self-interaction energy of a unit cell and the interaction energy between the unit cells. The edge perturbation is applied to the selected atoms of ABNNRs and ZBNNRs to simulate the electronic properties changes. This simulation work is done by generating a custom script using numerical computational methods in MATLAB software. When benchmarked against a reference study, our results aligned closely in terms of band structure and bandgap energy for ABNNRs. However, variations were observed in the peak values of the continuous curves for the local density of states. This discrepancy can be attributed to the use of numerical methods in our study, in contrast to the semi-analytical approach adopted in the reference work.

• Clinical Nutrition Research
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• v.12 no.1
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• pp.7-20
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• 2023

Creating a complex balance between dietary composition, circadian rhythm, and the hemostasis control of energy is important for managing diseases. Therefore, we aimed to determine the interaction between cryptochrome circadian clocks 1 polymorphism and energy-adjusted dietary inflammatory index (E-DII) on high-sensitivity C-reactive protein in women with central obesity. This cross-sectional study recruited 220 Iranian women aged 18-45 with central obesity. The 147-item semi-quantitative food frequency questionnaire was used to assess the dietary intakes, and the E-DII score was calculated. Anthropometric and biochemical measurements were determined. By polymerase chain response-restricted length polymorphism method, cryptochrome circadian clocks 1 polymorphism was assigned. Participants were categorized into three groups based on the E-DII score, then categorized according to cryptochrome circadian clocks 1 genotypes. The mean and standard deviation of age, BMI, and high-sensitivity C-reactive protein (hs-CRP) were 35.61 ± 9.57 years, 30.97 ± 4.16 kg/m², and 4.82 ± 5.16 mg/dL, respectively. The interaction of the CG genotype and E-DII score had a significant association with higher hs-CRP level compared to GG genotype as the reference group (β, 1.19; 95% CI, 0.11-2.27; p value, 0.03). There was a marginally significant association between the interaction of the CC genotype and the E-DII score with higher hs-CRP level compared to the GG genotype as the reference group (β, 0.85; 95% CI, -0.15 to 1.86; p value, 0.05). There is probably positive interaction between CG, CC genotypes of cryptochrome circadian clocks 1, and E-DII score on the high-sensitivity C-reactive protein level in women with central obesity.

• Journal of Institute of Control, Robotics and Systems
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• v.17 no.11
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• pp.1159-1167
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• 2011

A novel 3D tube scanning technique is proposed. The proposed tube scanning technique is developed for a special tube inspection module which consists of four line-lasers and one camera. Using the scanning module, we can reconstruct the 360 degree shapes of the inner surfaces of a cylindrical tube. From an image frame captured by the camera, we reconstruct a partial tube model based on four laser triangulations. Then by aligning such partial models with respect to a reference tube axis, a complete 3D shape of the tube is reconstructed. The tube axis in each reconstructed frame is aligned with a 3D Euclidean transformation to the reference axis. Several experiments show that the proposed method can align multiple tube axes very accurately and reconstruct 3D shapes of a tube with very low shape distortion.

• Journal of Power Electronics
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• v.14 no.1
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• pp.125-134
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• 2014

This paper presents a robust and speed-sensorless stator flux estimation for induction motor direct torque control. The proposed observer is based on sliding mode approach. Stator electrical equations are used in the rotor orientation reference frame to eliminate the observer dependence on rotor speed. Lyapunov's concept for systems stability is adopted to confine the observer gain. Furthermore, the sensitivity of the observer to parameter mismatch is recovered with an adaptation technique. The nonlinearities of the pulse width modulation voltage source inverter are estimated and compensated to enhance stability at low speeds. Therefore, a new method based on the model reference adaptive system is proposed. Simulation and experimental results are shown to verify the feasibility and effectiveness of the proposed algorithms.

• Journal of the Korean Society of Costume
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• v.39
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• pp.271-281
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• 1998

The purposes of this study were to deter-mine the dimensions of the housewives' cloth-ing behavior for the environmental protection and the identify the effective variables. The results of this study was intended to provide fundamental material for the establishment of clothing behavior guidelines for the environmental protection. This study was conducted by reference analysis and empirical study. To develop theoreti-cal framework study. To develop theoreti-cal framework of dimensions of environmental protection behavior, references concerned were analyzed. The results of reference analy-sis showed that the dimensions of environmental protection bahavior were resource and energy saving, sold waste reduction, resource reuse or recycle, and green product purchase. The dimensions of housewives' clothing behavior for environmental protection were identified by use of self-administered questionnaires. The results of enpirical study showed that the dimensions of clothing behavior for the environmental protection wre clothing resource reuse or recycle, clothing management resource saving, clothing consumption resource saving, green product purchase, and clothing management resource saving was the highest and that of resource reuse or recycle was the lowest. Environmental consciousness, taking environmental education or not, residing place, clothing seperate-collectiong at residing place were effective variables on clothing behavior for environmental protection.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.684_685
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• 2009

A digital sampling algorithm that uses a two high resolution integrating Voltmeters which are synchronized by Phase Lock Loop (PLL) time clock for accurately measuring the parameters, active and reactive power, for sinusoidal power measurements is presented. The PLL technique provides high precision measurements, root mean square (rms), phase and complex voltage ratio, of the AC signal. The system has been designed to be used at the Korean Research Institute of Standards and Science (KRISS) as a reference power standard for electrical power calibrations. The test results have shown that the accuracy of the measurements is better than $10 {\mu}W/VA$ and the level of uncertainty is valid for the power factor range zero to 1 for both lead and lag conditions. The system is fully automated and allows power measurements and calibration of high precision wattmeters and power calibrators at the main power frequencies 50 and 60 Hz.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.57.2-57.2
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• 2011

In this study, the effects of shear flows around a 2-dimensional airfoil, S809 on its aerodynamic characteristics were analyzed by CFD simulations. Various parameters including reference inflow velocity, shear rate, angle of attack, and cord length of the airfoil were examined. From the simulation results, several important characteristics were found. Shear rate in a flow makes some changes in the lift coefficient depending on its sign and magnitude but angle of attack does not have a distinguishable influence. Cord length and reference inflow also cause proportional and inversely proportional changes in lift coefficient, respectively. We adopted an analytic expression for the lift coefficient from the thin airfoil theory and proposed a modified form applicable to the traditional load analysis procedure based on the blade element momentum theory. Some preliminary results applied to an well known load simulation software, FAST, are presented.