• Journal of Environmental Science International
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• v.25 no.1
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• pp.99-105
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• 2016

In this paper, a groundwater hydrological study of the Gyeongju well during the Silla period is conducted to investigate how sufficiently the Gyeongju well supplied water demand at the time. It is assumed that the current geology and soil condition in Gyeongju remain similar to the Silla period. Also, the land use and land coverage during the Silla period is estimated based on the current land condition in Gyeongju. Precipitation during the Silla period is analyzed using precipitation data from 1984 to 2014 provided by Gyeonju weather station. Precipitation analysis is applied based on 3 different scenarios; precipitation intensity during the Silla period was Case (1) the same as, Case (2) 30% more, and Case (3) 30% less than the precipitation intensity of the last decade (2005~2014). Furthermore, to observe the use of the well in Gyeongju during droughts, the following condition(Case (4)) is also considered; ten year drought during the Silla period was the same as the ten year drought from 1984 to 2014. Available amount of groundwater development is analyzed using NRCS-CN method. The results show that the potential amount of groundwater in Gyeongju during Silla era was for Case (1) $62,825,272m^3/year$, Case (2) $93,606,567m^3/year$, Case (3) $32,277,298m^3/year$, and Case (4)$32,870,896m^3/year$. Also, it has been shown that $45,260,000m^3$ of groundwater were required to supply to all households in Gyeongju during Silla era. Therefore, if the precipitation intensity during Silla era was similar with the last decade, the groundwater would provide enough supply to all households in Gyeongju. However, in the case that the precipitation intensity during Silla era was 30% less than the last decade or a ten year drought happened, it is predicted that the water use in Gyeongju would have been limited.

• Korean Journal of Medicinal Crop Science
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• v.26 no.5
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• pp.417-429
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• 2018

Background: The objective of this study was to make colloidal dispersions of the active compounds of radix of Angelica gigas Nakai that could be charaterized as nano-composites using hot melt extrusion (HME). Food grade hydrophilic polymer matrices were used to disperse these compound in aqueous media. Methods and Results: Extrudate solid formulations (ESFs) mediated by various HPMCs (hydroxypropyl methylcelluloses) and Na-Alg polymers made from ultrafine powder of the radix of Angelica gigas Nakai were developed through a physical crosslink method (HME) using an ionization agent (treatment with acetic acid) and different food grade polymers [HPMCs, such as HP55, CN40H, AN6 and sodium alignate (Na-Alg)]. X-ray powder diffraction (XRD) analysis confirmed the amorphization of crystal compounds in the HP55-mediated extrudate solid formulation (HP55-ESF). Differential scanning calorimetry (DSC) analysis indicated a lower enthalpy (${\Delta}H=10.62J/g$) of glass transition temperature (Tg) in the HP55-ESF than in the other formulations. Infrared fourier transform spectroscopy (FT-IR) revealed that new functional groups were produced in the HP55-ESF. The content of phenolic compounds, flavonoid (including decursin and decursinol angelate) content, and antioxidant activity increased by 5, 10, and 2 times in the HP55-ESF, respectively. The production of water soluble (61.5%) nano-sized (323 nm) particles was achieved in the HP55-ESF. Conclusions: Nano-composites were developed herein utilizing melt-extruded solid dispersion technology, including food grade polymer enhanced nano dispersion (< 500 nm) of active compounds from the radix of Angelica gigas Nakai with enhanced solubility and bioavailability. These nano-composites of the radix of Angelica gigas Nakai can be developed and marketed as products with high therapeutic performance.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.43 no.3
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• pp.179-183
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• 1998

The cyanidin 3-glucoside (C3G) extracted from pigmented rice seeds in 0.5% TFA (Trifluoro acetic acid) -95% ethanol was separated by High Performance Liquid Chromatography (HPLC). A HPLC system using a Develosil ODS-5 column and 0.1 % TFA-$H_2O$～0.1 % TFA-$CH_3CN$ gradient elution was selected for separation and quantitative determination of C3G. Regression equation obtained for the standard content of C3G pigment was as Y=21.95293$^*$X-14.726771 (r=0.99$^{**}$). Using this method, 326 domestic and introduced collections were evaluated for the C3G content. The Korean bred cultivar 'Heugjinjubyeo', showed highest C3G content (552 mg/100g seed) among the tested cultivars. Among the pigmented rice cultivars ten cultivars were selected for containing a high content of C3G. The content of C3G per 100g seeds was in high order as follows: Heugjinjubyeo (552mg)>Cheng Chang (321mg)>Kilimgeugmi (240mg)>PI160979-2 (224mg)>Hong Shei Lo (221mg)>Heugnambyeo (191 mg)>Mitak =PIl60979-1 (186mg)>Suwon425 (163mg)>Sanghaehyanghyeolla (108mg). The C3G pigment was not detected in the common white rice cultivars.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1195-1198
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• 2013

Nickel hexacyanoferrate supported palladium nanoparticles (Pd-NiHCF NPs) were synthesized and studied for oxygen reduction reactions in direct methanol fuel cell. The NiHCF support was readily synthesized by a comixing of $Ni(OCOCH_3)_2$ and equimolar $K_3[Fe(CN)_6]$ solution into DI water under rigorous stirring. After the preparation of NiHCF support, Pd NPs were loaded on NiHCF via L-ascorbic acid reduction method at $80^{\circ}C$. Pd-NiHCF NPs were electrochemically active for oxygen reduction reaction in 0.1 M $HClO_4$ solution. X-ray absorption near edge structure analysis was conducted to measure the white line intensity of Pd-NiHCF to verify the OH adsorption. As a comparison, carbon supported Pd NPs exhibited same white line intensity. This study provides a general synthetic approach to easily load Pd NPs on porous coordination polymers such as NiHCF and can provide further light to load Pd based alloy NPs on NiHCF framework.

• Journal of Korean Medicine Rehabilitation
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• v.27 no.2
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• pp.39-54
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• 2017

Objectives This study aimed to search the Chinese literature on acupotomy for lumbar disc herniation and to analyze their methodologies. Methods Using 4 Chinese databases (CBM [www.sinomed.ac.cn], CNKI [www.cnki.net], WANFANG [www.wanfangdata.com], and WEIPU [www.cqvip.com]), we searched for clinical trials conducted in China over the past 10 years on acupotomy for lumbar disc herniation. The search terms used were "(腰椎椎間板脫出症 or 椎間板脫出症 or 椎間板脫出) and (针刀or 针刀松解术)" and we selected only meta-analyses that were published before December 2016. From among these meta-analyses, we excluded duplicates and selected the remaining 36 randomized controlled trials (RCTs) for our final analysis. Results The largest numbers of acupotomy papers were published in 2008 and 2013 (8 papers each). The average number of subjects was 120; the most common treatment method used for the control group was standard acupuncture (in 11 papers), and the most common concurrent treatment in the treatment group was massage (in 10 papers). The most common site of needle insertion was between the spinous processes, or at less than 0.5 cm on either side of the spinous processes (in 24 papers). The most common site of adhesion lysis was at the transverse process (in 24 papers). Two studies were blinded, and the mean Jadad score was 1.17. Conclusions A large number of RCTs on the use of acupotomy for lumbar disc herniation are conducted every year in China, and the procedure has been shown to be very effective, with few adverse effects. However, the average quality of the studies was not very high. Based on our study, we expect several high-quality clinical trials on acupotomy to be conducted in Korea in the future.

• Journal of Power Electronics
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• v.11 no.3
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• pp.294-303
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• 2011

In this paper an effective five-phase induction motor (IM) and its drive methods are proposed. Due to the additional degrees of freedom, the five-phase IM drive presents unique characteristics for enhancing the torque producing capability of the motor. Also the five-phase motor drives possess many other advantages when compared to traditional three-phase motor drives. Some of these advantages include, reducing the amplitude and increasing the frequency of the torque pulsation, reducing the amplitude of the current without increasing the voltage per phase and increasing the reliability. In order to maximize the torque per ampere, the proposed motor has concentrated winding, the produced back electromotive force (EMF) is almost trapezoidal, and the motor is supplied with the combined sinusoidal plus the third harmonic of the currents. For demonstrating the superior performance of the proposed five-phase IM, the motors are also analyzed on the synchronously rotating reference frame. To supply trapezoidal current waveform and to exclude the effect of the $3^{rd}$ harmonic current, a new control stratagem is proposed. The proposed control method is based on direct torque control (DTC) and rotor flux oriented control (RFOC) of the five-phase IM drives. It is able to reduce the acoustical noise, the torque, the flux, the current, and the speed pulsations during the steady state. The DTC transient merits are preserved, while a better quality steady-state performance is produced in the five phase motor drive for a wide speed range. Experimental results clearly demonstrated a more dynamic steady state performance with the proposed control system.

• Journal of Korean Society on Water Environment
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• v.34 no.4
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• pp.382-390
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• 2018

In this study, the LIDMOD3 was developed to design and evaluate low impact development (LIDMOD). In the same fashion, the LIDMOD3 employs a curve number (NRCS-CN) method to estimate the surface runoff, infiltration and event mean concentration as applicable to pollutant loads which are based on a daily time step. In these terms, the LIDMOD3 can consider a hydrologic soil group for each land use type LID-BMP, and the applied removal efficiency of the surface runoff and pollutant loads by virtue of the stored capacity, which was calculated by analyzing the recorded water balance. As a result of Model development, the LIDMOD3 is based on an Excel spread sheet and consists of 8 sheets of information data, including: General information, Annual precipitation, Land use, Drainage area, LID-BMPs, Cals-cap, Parameters, and the Results. In addition, the LIDMOD3 can estimate the annual hydrology and annual pollutant loads including surface runoff and infiltration, the LID efficiency of the estimated surface runoff for a design rainfall event, and an analysis of the peak flow and time to peak using a unit hydrolograph for pre-development, post-development without LID, and as calculated with LID. As a result of the model application as applied to an apartment, the LIDMOD3 can estimate LID-BMPs considering a well spatical distributed hydroloic soil group as realized on land use and with the LID-BMPs. Essentially, the LIDMOD3 is a screen level and simple model which is easy to use because it is an Excel based model, as are most parameters in the database. This system can be expected to be widely used at the LID site to collect data within various programmable model parameters for the processing of a detail LID model simulation.

• Women's Health Nursing
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• v.9 no.1
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• pp.50-60
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• 2003

Purpose : The purpose of this study was to evaluate the factors which are related to the maternal role performance of first-time mother to improve the health of infant. Specifically a basic hypothetical model was developed based on the previous study about a model of social networks. Method : The survey was done from January to February in 2001. Total 257 mothers who have four to twelve month old first-time baby was interviewed in five community health center around country(Seoul, Choung-ju, Asan, Cheon-an, Jeju). Finally 247 data was analyzed. Data analysis was done with LISREL 8.20 program for covariance structural analysis. Results : Compared to the hypothetical model, the revised model has become parsimonious and had a better fit to the data ($X^2=167.55$ (p값=.00), $x^2/df=1.48$, GFI=0.97, AGFI=0.95, RMR=0.049, NFI=0.98, NNFI=0.99, CN=222.53). All predictive variables of the maternal role of first-time mother explained 30% of total variance in model. Social network structural characteristics and social network interactional characteristics had significant effect on the emotional support and the information support. And social network interactional characteristics had significant effect on the service support, material support and social companionship support. The service support and social companion ship support had significant effect on the maternal role strain. The emotional support and the social companion ship support had significant effect on the maternal role of first-time mother. Conclusion : As the conclusion of this study, there is in need of the developing the programmes focussed on the social network for the first-time mother.

• Bulletin of the Korean Chemical Society
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• v.21 no.7
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• pp.720-726
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• 2000

The analytic gradient method for the equation-of-motion coupled-cluster singles and doubles (EOM-CCSD) energy has been extended to employ a reduced molecular orbital (MO) space. Not only the innermost core MOs but also some of the outermost virtua l MOs can be dropped in the reduced MO space, and a substantial amount of computation time can be reduced without deteriorating the results. In order to study the magnitudes and trends of the effects of the dropped MOs, the geometries and vibrational properties of the ground and excited states of BF, CO, CN, N2, AlCl, SiS, P2, BCl, AIF, CS, SiO, PN and GeSe are calculated with different sizes of molecular orbital space. The 6-31 G* and the aug-cc-pVTZ basis sets are employed for all molecules except GeSc for which the 6-311 G* and the TZV+f basis sets are used. It is shown that the magnitudes of the drop-MO effects are about $0.005\AA$ in bond lengths and about 1% on harmonic frequencies and IR intensities provided that the dropped MOs correspond to (1s), (1s,2s,2p), an (1s,2s,2p,3s,3p) atomic orbitals of the first, the second, and the third row atoms, respectively. The geometries and vibrational properties of the first and the second excited states of HCN and HNC are calculated by using a drastically reduced virtual MO space as well as with the well defined frozen core MO space. The results suggest the possibility of using a very smalI MO space for qualitative study of valence excited states.

• Bulletin of the Korean Chemical Society
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• v.19 no.6
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• pp.654-660
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• 1998

$[Fe^{II}Fe^{III}BPLMP(OAc)_2](BPh_4)_2$ (1), a new model for the reduced form of the purple acid phosphatases, has been synthesized by using a dinucleating ligand, 2,6-bis[((2-pyridylmethyl)(6-methyl-2-pyridylmethyl)amino) methyl]-4-methylphenol (HBPLMP). Complex I has been characterized by X-ray diffraction method as having (μ-phenoxo)bis(acetato)diiron core. Complex 1 was crystallized in the monoclinic space group C2/c with the following cell parameters: a=41.620(6) Å, b=14.020(3) Å, c=27.007(4) Å, β=90.60(2)°, and Z=8. The iron centers in the complex 1 are ordered as indicated by the difference in the Fe-O bond lengths which match well with typical $Fe^{III}-O\; and\; Fe^{II}-O$ bond lengths. Complex 1 has been studied by electronic spectral, NMR, EPR, SQUID, and electochemical methods. Complex 1 exhibits strong bands at 592 nm, 1380 nm in $CH_3CN$ (ε = 1.0 × 103 , 3.0 × 102). These are assigned to $phenolate-to-Fe^{III}$ and intervalence charge-transfer transitions, respectively. Its NMR spectrum exhibits sharp isotropically shifted resonances, which number half of those expected for a valence-trapped species, indicating that electron transfer between $Fe^{II}\;and\;Fe^{III}$ centers is faster than NMR time scale. This complex undergoes quasireversible one-electron redox processes. The $Fe^{III}_2/Fe^{II}Fe^{III}\;and\;Fe^{II}Fe^{III}/Fe^{II}_2$ redox couples are at 0.655 and -0.085 V vs SCE, respectively. It has $K_{comp}=3.3{\times}10^{12}$ representing that BPLMP/bis(acetate) ligand combination stabilizes a mixed-valence $Fe^{II}Fe^{III}$ complex in the air. Complex 1 exhibits a broad EPR signal centered near g=1.55 which is a characteristic feature of the antiferromagnetically coupled high-spin $Fe^{II}Fe^{III}$ system $(S_{total}=1/2)$. This is consistent with the magnetic susceptibility study showing the weak antiferromagnetic coupling $(J= - 4.6\;cm^{-1},\; H= - 2JS_1{\cdot}S2)$ between $Fe^{II}\; and \;Fe^{III}$center.