• Journal of the Korean Crystal Growth and Crystal Technology
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• v.33 no.5
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• pp.167-173
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• 2023

Li₃V₂(PO₄)₃ and Li₃V₂(PO₄)₃/C composite with single phase monoclinic structure for the cathode materials are successfully synthesized by direct co-precipitation method using N₂H₄·H₂O as the reducing agent and alginic acid as the carbon source, and their electrochemical properties were compared. The particles with approximately 1~2 ㎛ size and the uniform spherical-like morphology of the narrow particle size distribution were obtained. In addition, the residual carbon can also improve the electrical conductivity. The Li₃V₂(PO₄)₃/C composite has improved initial specific discharge capacity and excellent cycle characteristics to maintain capacity stably than Li₃V₂(PO₄)₃. The results indicate that the reducing agent and carbon composite can affect the good crystallinity and electrochemical performance of the cathode materials.

• Journal of architectural history
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• v.22 no.4
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• pp.7-18
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• 2013

Integrated-Salmi can be suggested as a character of Da-po type Kong-po in Korea's traditional architecture. However, only few studies are made on this subject yet. This study is to investigate the integration process of Salmi through cases of certain Kong-po which have the same number of inner and outer Chul-mok and are also known to precede in time. The results of the study are like below. First, Integrated-Salmi is more dominant in inner and outer 3 Chul-mok Kong-po than in inner and outer 2 Chul-mok Kong-po. Second, While inner and outer 2 Chul-mok prevail in Yeong-nam region, inner and outer 3 Chul-mok prevail in Ho-nam region. Third, integrated Salmi of Inner and outer 3 Chul-mok, first appeared in internal Jusangpo to be carried over to internal Juganpo then eventually to outer Salmi. Fourth, the reason why integrated form precede in internal salmi of inner and outer 3 Chul-mok Kong-po is due to 2 main factors. First of which is the impact of integrated Boaji that developed in Da-po type since the early 16th century. The second factor is downward expansion of Cho-gak's Boaji which was adopted to cope with disorders made in structure of Chum-Cha, due to inner and outer 3 Chul-mok type buddhist temples' wide reconstruction throughout Jeolla region following the Japanese invasion of Korea in 1592. This study is to disclose the regularity of development process of Salmi's Cho-gak(草刻) which is a characteristic of Korea's Da-po type Kong-po.

• The Journal of Pediatrics of Korean Medicine
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• v.1 no.1
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• pp.1-12
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• 1986

The Woo-Whang-po-Lyong-Whan has been used as one of the traditional medicines in the field of pediatrics so far since Song dynasty, and still it is widely being used nowadays. It might be considered to be a contribution to do further basic experimental studies on antipyretic, anticonvulsive and analgetic action of the Woo-Whang-po-Lyong-Whan. So it's pharmacological studies were carried out comparing to control drugs. ?Following conclusions were obtained. 1. It's antipyretic action was compared to that of aspirin by Writhing response using acetic acid-method. Mice were given one twentith, one tenth and one fifth tablets of the Woo-Whang-po-Lyong-Whan per Kg of body weight, respecitively. Writhing syndrome frequencies were noted as 38.4 in control group. and $18.0{\pm}12$, $13.17{\pm}2.28$, $7.33{\pm}12$ in above esperimental groups, respectively. In aspirin group it was $18.5{\pm}1.0$ when 2mg aspirin per body weight of mice was given. So it was recognized that antipyretic action of the Woo-Whang-Po-Lyong-Whan become remarkable by increasing amounts of the Woo-Whang-Po-Lyong-Whan. ?2. Antipyretic action in normal temperature mice group was not significant by increasing concentration of the Woo-Whang-Po-Lyong-Whan, but body temperature dropping in normal mice group was slightly noted than control. group, but less temperature dropping was noted than aminopyrin group. ?3. In fever provocated rats groups using Salmonella typhimurium, antipyretic action of the Woo-Whang-Po-Lyong-Whan was not observed significantly than control group. And slight antipyretic action was noted in aminopyrin group. So that antipyretic action of the Woo-Whang-Po-Lyong-Whan was not significant than those of general antipyretic used nowadays, but slower action was recognized. ?4. Anticonvulsive action of the Woo-Whang-Po-Lyong-Whan was studies comparing to that of phenobarbital. Action was not remarkable than phenobarbital, but was significant than control group. No significant intesifying action was noted by increasing amounts of the Woo-Whang-Po- Lyong-Whang.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.5
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• pp.601-606
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• 2014

The IPO(Iterative Physical Optics) method repeatedly applies the well-known PO(Physical Optics) approximation to calculate the scattered field by a large object. Thus, the IPO method can consider the multiple scattering in the object, which is ignored for the PO approximation. This kind of iteration can improve the final accuracy of the induced current on the scatterer, which can result in the enhancement of the accuracy of the RCS(Radar Cross Section) of the scatterer. Since the IPO method can not exactly but approximately solve the required integral equation, however, the convergence of the IPO solution can not be guaranteed. Hence, we apply the famous techniques used in the inversion of a matrix to the IPO method, which include Jacobi, Gauss-Seidel, SOR(Successive Over Relaxation) and Richardson methods. The proposed IPO methods can efficiently calculate the RCS of a large scatterer, and are numerically verified.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.45 no.1
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• pp.1-9
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• 2022

The PoN (Proof of Nonce) distributed consensus algorithm basically uses a non-competitive consensus method that can guarantee an equal opportunity for all nodes to participate in the block generation process, and this method was expected to resolve the first trilemma of the blockchain, called the decentralization problem. However, the decentralization performance of the PoN distributed consensus algorithm can be greatly affected by the network transaction transmission delay characteristics of the nodes composing the block chain system. In particular, in the consensus process, differences in network node performance may significantly affect the composition of the congress and committee on a first-come, first-served basis. Therefore, in this paper, we presented a problem by analyzing the decentralization performance of the PoN distributed consensus algorithm, and suggested a fairness control algorithm using a learning-based probabilistic acceptance rule to improve it. In addition, we verified the superiority of the proposed algorithm by conducting a numerical experiment, while considering the block chain systems composed of various heterogeneous characteristic systems with different network transmission delay.

• Journal of Society of Preventive Korean Medicine
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• v.19 no.1
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• pp.131-144
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• 2015

Objective : This study was conducted to investigate anti-obesity effects of mixed-Powder(Raphani Semen, Coicis Semen, Poria, Plantaginis Testa & Theae folium)(HP) & mixed water extract(Citri Pericarpium, Crataegi Fructus, Maydis Stigma, Allium Skin) (HE) in mice fed a high-fat diet. Method : 50 Female ICR mice were divided into six groups; Normal group (Ve), high-fat diet group (Po), Po+HP(0.6g/kg) group(HP), Po+HE(1g/kg) group(HE), Po+(HP+HE) group(HPE), Po+(HP+HE)*2 group(DHPE). For 8 weeks, these groups were fed their respective diets. Body weight, liver weight and weights of adipose tissues, GOT/GPT index changes & Blood Glucose index changes were measured respectively. Lipid profiles in serum were analyzed by kit of blood. Results : Groups HP, HE, HPE, DHPE had significantly reduced body weight, liver weight, adipose tissue weights and GOT/GPT index, blood glucose index compared to the Po group. Also, serum triglyceride and total cholesterol, low density lipoprotein, were significantly reduced when compared to the Po group. Group G1 had significantly increased high density lipoprotein levels. Conclusion : Mixed powder (HP) & mixed water extract (HE) show anti-obesity effects in mice fed a high-fat diet.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.363-364
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• 2007

Phospho-olivine $LiFePO_4$ cathode materials were prepared by hydrothermal reaction at different temperatures. The structural performance of $LiFePO_4$ powders were characterized by X-ray diffraction (XRD). $LiFePO_4$/Li batteries were characterized electrochemically by charge/discharge experiments. The XRD results demonstrate that $LiFePO_4$ powder has an orthorhombic olivine-type structure with a space group of Pnmb. Among the synthesized cathode materials, $LiFePO_4$synthesized at $170^{\circ}C$ and subsequently annealed at $500^{\circ}C$ shows the best electrochemical properties. It shows initial discharge capacity of $167\;mAh\;g^{-1}$ (98% of the theoretical capacity) close to the theoretical capacity of $LiFePO_4$ ($170\;mAh\;g^{-1}$) at 0.1 C rate, which is ascribed to the enhanced degree of crystallinity, better phase purity, more spherical and more finely dispersed nanoparticles, crystallization and activation of small amount impurity.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.2
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• pp.186-196
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• 2017

In order to resolve the trimming difficulty in rotor CFD calculations, a high-efficiency and improved "delta trim method" is established to compute the blade control settings that are necessary to identify the blade motion. In this method, a simplified model which combines the blade element theory and different inflow models is employed to calculate the control settings according to the target aerodynamic forces, then it is coupled into a CFD solver with unsteady Navier-Stokes equations by the delta methodology, which makes the control settings and aerodynamics calculated and updated in the meantime at every trim cycle. Different from the previous work, the current research combines the inflow model based on prescribed wake theory. Using the method established, the control settings and aerodynamic characteristics of Helishape 7A, AH-1G and Caradonna-Tung rotors are calculated. The influence of different inflow models on trimming calculations is analyzed and the computational efficiency of the current "delta trim method" is compared with that of the "CFD-based trim method". Furthermore, for the sake of improving the calculation efficiency, a novel acceleration factor method is introduced to accelerate the trimming process. From the numerical cases, it is demonstrated that the current "delta trim method" has higher computational efficiency than "CFD-based trim method" in both hover and forward flight, and up to 70% of the amount of calculation can be saved by current "delta trim method" which turns out to be satisfactory for engineering applications. In addition, the proposed acceleration factor shows a good ability to accelerate the trim procedure, and the prescribed wake inflow model is always of better stability than other simple inflow models whether the acceleration factor is utilized in trimming calculations.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.1
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• pp.60-65
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• 1991

The hydrothermal growth of $GaPO_{4}$ Single Crystals was carried out by the horizontal temperature gradient method. The most promising solvents for the crystal growth of $GaPO_{4}$ are $H_{3}PO_{4}$ and HCl solutions. Single crystals have been hydothermally grown at temperatures over the range $210-290^{\circ}C$ in these solutions with seed crystals. The glowth rates in HCl solution were higher than that for comparable conditions in $H_{3}PO_{4}$ solution. Morphologies of crystals grown at temperatures below $200^{\circ}C$ tended to be bounded by small major rhombohedral(10$\bar{1}$1) faces. In the temperature range from 200 to $430^{\circ}C$, the single crystals have morphologies bounded by prism (10$\bar{1}$0), small major rhombohedral(10$\bar{1}$1) and minor rhombohedral(01$\bar{1}$1) faces at the early stage, and grew with well developed basal(0001) faces by increasing the growth temperature.

• Journal of Electrochemical Science and Technology
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• v.3 no.4
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• pp.172-177
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• 2012

Mo-doped $LiFePO_4$ was synthesized via co-precipitation method using sucrose as the carbon source. Structure, surface morphology, and the electrochemical properties of the synthesized olivine compounds were investigated using Rietveld refinement of X-ray diffraction data (XRD), scanning electron microscopy (SEM), and electrochemical charge-ischarge tests. Spherical morphology with the particle size of ${\sim}8{\mu}m$ authenticated the enhanced tap density and volumetric energy density of the synthesized materials. Charge-discharge behavior of $LiFePO_4$ and Mo-doped $LiFePO_4$ cells demonstrated a specific capacity of 130 and 145 mAh $g^{-1}$, respectively. Mo-doped $LiFePO_4$ cells exhibited an excellent discharge capacity at 96 mAh $g^{-1}$ at 7 C-rate.