• Journal of the Mineralogical Society of Korea
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• v.3 no.1
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• pp.1-6
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• 1990

Clacic amphiboles along the tremolite (Tr)-tschermakite(Ts) joint were synthesized using a piston-cylinder appratus. At 750-85$0^{\circ}C$and 12-2 kb, amphibole+corundum coexist with zoisite($\pm$talc, chlorite, and Mg-staurolite), but with anorthite($\pm$cholorite, spinel, pyroxenes, and sapphirine) at lower P. At 90$0^{\circ}C$, amphibole+corundum+clinopyroxene($\pm$anorthite, forsterite, sapphirine, and garnet) are stable over the P range 12-18 kb. These amphibole-bearing assemblages are replaced at high P by clcinopyroxene+talc+chlorite+zoisite at 650-75$0^{\circ}C$, and at higher temperatures by garnet+clinopyroxene($\pm$zoisite, orthopyroxene, and Mg-staurolite). Synthetic amphiboles with Ts>~45 mol% contain as much as 0.15 excess cations per formula unit(pfu) based on 23 oxygens(anhydrous formula), whereas less tschermakitic ones are deficient in cation occupancy by up to 0.18 pfu. This trend is attributed to the 야/trioctahedral substitution in Ca-amphiboles. Compositions of synthetic amphiboles display systematic changes with P and T governed by coexisting mineral assemblages. The Ts content (=[8-Si-Na]/2) increases with increasing T( Ts/ T=~0.1 nik% K-1) in the range 750-85$0^{\circ}C$, but remains nearly constant at 850-90$0^{\circ}C$. Pressure dramatically affects the Ts content of Ca-amphiboles:it increases with P at 8-12 kb( Ts/ T=2-3 mol% K-1), but significantly decreases at 12-21 kb( Ts/ P=-2.5 mol% Kb-1). Hence, the most tschermakitic amphiboles, containing 60$\pm$5 mol % Ts, or 1.2$\pm$0.1 tetrahedral Al, occur at 12 kb and 850-90$0^{\circ}C$. Compositions of Ca-amphiboles defined by a simple reaction, 3 Tr+2 zoisite+7 corundum+H2O=5 Ts, are reversed and used to estimate thermodynamic parameters of tschermakite assuming ideal mixing of Tr-Ts solid solutions. Predicted standard molal entropy and enthalpy of tschermakite are : S$^{\circ}$of Tr-Ts solid solutions. Predicted standard molal entropy and enthalpy of tschermakite are : S$^{\circ}$=566.9$\pm$13.7 J mol-1K, -1and H$^{\circ}$=-12518.36$\pm$15.17 kJ mol.-1

• Korean Journal of Materials Research
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• v.9 no.3
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• pp.234-239
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• 1999

A Abstract Yttria-stabilized zirconia(YSZ) thin films were synthesized by plasma enhanced chemical vapor deposition process. $Zr[TMHD]_4$ $Y[TMHD]_3$ precursors and oxygen were used with the deposition temperature of $425^{\circ}C$ and rf power ranging 0-100 watt. Effects of the deposition parameters were studied by X-ray diffraction and thickness anal­ysis. YSZ thin films have cubic crystal structure with (200) orientation. From the results of EDX analysis, the converte ed content of TEX>$Y_2O_3$ was determined to be 0-36%, and the film thickness was increased with bubbling temperature which is considered to be due to increasing TEX>$Y_2O_3$ flux. The depth profiles of Zr, Y and 0 appeared relatively $\infty$nstant through film thickness. Columnar grains of $1000~2000\AA$ grew vertical to the substrate surface for the case of Ar carri­er gas. In case of He carrier gas, the grain size was observed to be about $1000~2000\AA$. X-ray diffraction data showed the increase of lattice constant with TEX>$Y_2O_3$ content. It was that the presence of the cracks formed during film deposition, partially released the stress generated by the increase of lattice constant.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.277-284
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• 2011

To investigate the effects of arbuscular mycorrhizal (AM) symbiosis on N uptake and its assimilation under drought-stressed conditions in white clover, total $^{15}N$ amount and $^{15}N$ amount incorporated into $NO_3^-$, amino acids and soluble proteins were quantified by $^{15}N$ tracing during 7 days of water treatment. Under well-watered conditions, there were no significant effects of AM symbiosis on all parameters analyzed in this study. Drought stress decreased total $^{15}N$ amount both in AM and non-AM plants, with a lower rate in AM plants (-13.8%) relative to non-AM plants (-28.5%) at day 7. Drought significantly increased $^{15}N-NO_3^-$ amount in non-AM plants. The amount of $^{15}N$-amino acids was 1.26-fold and 1.33-fold higher, respectively, in leaves and roots of AM plants compared to those of non-AM ones. Drought decreased the amount of $^{15}N$-soluble proteins in leaves at day 7, with a higher rate in non-AM plants than in AM ones. These results clearly indicate that AM colonization effectively alleviating the decrease in N uptake, amino acids and proteins synthesis caused by drought stress.

• Journal of Nutrition and Health
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• v.38 no.8
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• pp.626-636
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• 2005

This study was undertaken to examine effects of dietary intake of garcinia cambogia extract, soy peptide and L-carnitine mixture on body weight gain and obesity-related bio-markers in rats fed high-fat diet for 9 weeks with or without regular treadmill exercise. Forty 5-week-old male Sprague-Dawley rats were randomly divided into four groups; sedentary control group (SC), exercised control group (EC), sedentary formula-fed group (SF), and exercised formula-fed group (EF). The SC and EC rats were fed high-fat control diet (fat comprises$40\%$ of total caloris), and SF and EF rats were fed high-fat formula (composed of garcinia cambogia, soy peptide and L-carnitine) supplemented diet. Statistical analyses by two-way ANOVA indicated that the regular treadmill exercise significantly lowered cumulative body weight gain, total visceral fat mass, and epididymal, perirenal and retroperitoneal fat pad weights, and serum concentrations of total cholesterol and LDL + VLDL cholesterol, insulin, c-peptide and leptin. Feeding the formula also resulted in significant reductions in cumulative body weight gain and visceral fat pad weights, along with other related parameters including serum total and LDL + VLDL cholesterol levels, and hepatic enzyme activities involved in fatty acid synthesis. Statistical analyses by one-way ANOVA revealed that the formula consumption significantly improved body weight gain ($18\%$ reduction), total visceral fat weight ($20\%$ reductions), and serum total ($43\%$ reduction) and LDL + VLDL cholesterol ($54\%$ reduction) levels, as well as serum levels of insulin ($49\%$ reduction), and c-peptide ($41\%$ reduction) in sedentary rats, but failed to exhibit significant reductions in these indices in animals under treadmill exercise program. Taken together, these results suggest that the treadmill exercise per n exhibited significant improvements in body fat reduction and other related bio-markers, and so the formula consumption did not achieve a further significant reductions in these bio-markers in exercised rats. Nevertheless, animals fed the formula with regular exercise showed the most efficient weight reduction compared to other groups either fed formula without exercise or received regular exercise without dietary supplementation.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.2
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• pp.211-218
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• 2021

This paper addressed the problems of controlling the coupled pitch-roll motions in a marine vessel exposed to the regular waves in the longitudinal and transversal directions. Stabilization of the pitch and roll motions can be regarded as the essential task to ensure the safety of a ship's navigation. One of the important features in the pitch-roll motions is the resonance phenomena, which result in unexpected large responses in terms of pitch and roll modes in some specific conditions. Besides, owing to its inherent characteristics of coupled combination and nonlinearity of restoring terms, the vessel shows various dynamical behaviors according to the system parameters, especially in the pitch responses. Above all, it can be seen that suppression of pitch rate remains the most significant challenge to overcome for ship maneuvering safety studies. To secure the stable upright condition, a quasi-sliding mode control scheme is employed to reduce the undesirable pitch and roll responses as well as chattering elimination. The Lyapunov theory is adopted to guarantee the closed stability of the pitch-roll system. Numerical simulations demonstrate the effectiveness of the control scheme. Finally, the control goals of state convergences and chattering reduction are effectively realized through the proposed control synthesis.

• Journal of Internet Computing and Services
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• v.22 no.6
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• pp.115-127
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• 2021

With the development of science and technology around the world, the realm of cyberspace, following land, sea, air, and space, is also recognized as a battlefield area. Accordingly, it is necessary to design and establish various elements such as definitions, systems, procedures, and plans for not only physical operations in land, sea, air, and space but also cyber operations in cyberspace. In this research, the importance of cyber targets that can be considered when prioritizing the list of cyber targets selected through intermediate target development in the target development and prioritization stage of targeting processing of cyber operations was selected as a factor to be considered. We propose a method to calculate the score for the cyber target and use it as a part of the cyber target prioritization score. Accordingly, in the cyber target prioritization process, the cyber target importance category is set, and the cyber target importance concept and reference item are derived. We propose a TIR (Target Importance Rank) algorithm that synthesizes parameters such as Event Prioritization Framework based on PageRank algorithm for score calculation and synthesis for each derived standard item. And, by constructing the Stuxnet case-based network topology and scenario data, a cyber target importance score is derived with the proposed algorithm, and the cyber target is prioritized to verify the proposed algorithm.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.86-96
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• 2006

Ecoclimap-1, a new complete surface parameter global database at a 1-km resolution, was previously presented. It is intended to be used to initialize the soil-vegetation- atmosphere transfer schemes in meteorological and climate models. Surface parameters in the Ecoclimap-1 database are provided in the form of a per-class value by an ecoclimatic base map from a simple merging of land cover and climate maps. The principal objective of this ecoclimatic map is to consider intra-class variability of life cycle that the usual land cover map cannot describe. Although the ecoclimatic map considering land cover and climate is used, the intra-class variability was still too high inside some classes. In this study, a new strategy is defined; the idea is to use the information contained in S10 NDVI SPOT/VEGETATION profiles to split a land cover into more homogeneous sub-classes. This utilizes an intra-class unsupervised sub-clustering methodology instead of simple merging. This study was performed to provide a new ecolimatic map over Northeast Asia in the framework of Ecoclimap-2 global database construction for surface parameters. We used the University of Maryland's 1km Global Land Cover Database (UMD) and a climate map to determine the initial number of clusters for intra-class sub-clustering. An unsupervised classification process using six years of NDVI profiles allows the discrimination of different behavior for each land cover class. We checked the spatial coherence of the classes and, if necessary, carried out an aggregation step of the clusters having a similar NDVI time series profile. From the mapping system, 29 ecosystems resulted for the study area. In terms of climate-related studies, this new ecosystem map may be useful as a base map to construct an Ecoclimap-2 database and to improve the surface climatology quality in the climate model.

• Tuberculosis and Respiratory Diseases
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• v.44 no.4
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• pp.822-835
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• 1997

Background : There have been many in vitro evidences that interleukin-4(IL-4) might be the most important cytokine inducing IgE synthesis from B-cells, and interferon-gamma(IFN-$\gamma$) might be a main cytokine antagonizing IL-4-mediated IgE synthesis. Recently some reports demonstrated that IFN-$\gamma$ might be used as a new therapeutic modality in some allergic diseases with high serum IgE level, such as atopic dermatitis or bronchial asthma. To evaluate the in vivo effect of IFN-$\gamma$ in bronchial asthma we tried a clinical study. Methods : Fifty bronchial asthmatics(serum IgE level over 200 IU/ml) who did not respond to inhaled or systemic corticosteroid treatment, and 17 healthy nonsmoking volunteers were included in this study. The CD 23 expressions of peripheral B-cells, the IL-4 activities of peripheral T-cells, the serum soluble CD23(sCD23) levels, and the superoxide anion(${O_2}^-$) generations by peripheral PMN were compared between bronchial asthmatics and normal subjects. The IL-4 activities of peripheral T-cells were analyzed by T-cell supernatant (T-sup)-induced CD23 expression from tonsil B-cells. In bronchial asthmatics the serum IgE levels and histamine $PC_{20}$ in addition to the above parameters were also compared before and after IFN-$\gamma$ treatment. IFN-$\gamma$ was administered subcutaneously with a weekly dose of 30,000 IU per kilogram of body weight for 4 weeks. Results : The ${O_2}^-$ generations by peripheral PMNs in bronchial asthmatics were higher than normal subjects($8.23{\pm}0.94$ vs $5.00{\pm}0.68\;nmol/1{\times}10^6$ cells, P<0.05), and significantly decreased after IFN-$\gamma$ treatment compared to initial values($3.69{\pm}0.88$ vs $8.61{\pm}1.53\;nmol/1{\times}10^6$ cells, P<0.05). CD23 expression of peripheral B-cells in bronchial asthmatics was higher than normal subjects($47.47{\pm}2.96%$, vs $31.62{\pm}1.92%$, P<0.05), but showed no significant change after IFN-$\gamma$ treatment. The serum sCD23 levels in bronchial asthmatics were slightly higher than normal subjects($191.04{\pm}23.3\;U/ml$ vs $162.85{\pm}4.85\;U/ml$), and 11(64.7%) of 17 patients showed a decreasing pattern in their serum sCD23 levels after IFN-$\gamma$ treatment. However the means of serum sCD23 levels were not different before and after IFN-$\gamma$ treatment. The IL-4 activities of peripheral T-cells in bronchial asthmatics were slightly higher than normal subjects($22.48{\pm}6.81%$ vs $18.90{\pm}2.43%$), and slightly increased after IFN-$\gamma$ treatment($27.90{\pm}2.56%$). Nine(60%) of 15 patients showed a decreasing pattern in their serum IgE levels after IFN-$\gamma$ treatment. And the levels of serum IgE were significantly decreased after IFN-$\gamma$ treatment compared to initial values ($658.67{\pm}120.84\;IU/ml$ vs $1394.32{\pm}314.42\;IU/ml$, P<0.05). Ten(83.3%) of 12 patients showed an improving pattern in bronchial hyperresponsiveness after IFN-$\gamma$ treatment, and the means of histamine $PC_{20}$ were significantly increased after IFN-$\gamma$ treatment compared to initial values ($1.22{\pm}0.29mg/ml$ vs $0.69{\pm}0.17mg/ml$, P<0.05). Conclusion : Our results suggest that IFN-$\gamma$ may be useful as well as safety in the treatment of bronchial asthmatics with high serum IgE level and that in vivo effects of IFN-$\gamma$ may be different from its in vitro effects on the regulations of IgE synthesis or the respiratory burst of PMN.

• Journal of the Mineralogical Society of Korea
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• v.16 no.3
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• pp.223-232
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• 2003

The co-precipitation method is applied to synthesize the cathode material Li[L $i_{x}$M $n_{1-x-y}$C $r_{y}$ ] $O_2$ for lithium rechargeable batteries at $650^{\circ}C$ (CR650) and 8$50^{\circ}C$ (CR850), respectively. Rietveld indices indicate that $R_{wp}$ with respect to $R_{exp}$ ( $R_{wp}$/ $R_{exp}$) are 9.2%/10.1% for CR650 and 15.9%/9.76% for CR850, respectively. $R_{B}$ and S (GofF) shows 10.9%, 8.54% and 1.9, 1.6, respectively. Rietveld structure refinement reveals that layer structure of LiMn $O_2$ (R3m) coexists with lower symmetry of Li[L $i_{1}$3/M $n_{2}$3/] $O_2$ (C2/c) due to superlattice ordering of Li and Mn in metal-transition containing layers. Unit-cell parameters are calculated as a=2.8520(2)$\AA$, c=14.248(2)$\AA$, V=100.40(l)$\AA^3$ for CR650, and a=2.8504(1)$\AA$, c=14.2371(7)$\AA$, V=100.179(8)$\AA^3$ for CR850. Final chemistry is obtained as Li[L $i_{0.35}$M $n_{0.56}$C $r_{0.09}$] $O_2$ (CR650) and Li[L $i_{0.27}$M $n_{0.61}$C $r_{0.13}$] $O_2$ (CR850), respectively.y...y..vely.y...y..

• Development and Reproduction
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• v.10 no.2
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• pp.147-154
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• 2006

Phthalates such as di(2-ethyl hexyl)phthalate(DEHP) are industrial chemicals with wide-ranging human exposures because of their use in plastics and other common consumer products. Consequently, their adverse effects as endocrine disruptor in the reproductive physiology of both laboratory rodents and human have been studied extensively. The present study was undertaken to examine whether prepubertal exposure to DEHP affects on the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in female rats. DEHP(100mg/kg/day) was administered daily from postnatal day 25(PND 25) through the day when the first vaginal opening(VO) was observed, and the animals were sacrificed on the next day. Gross anatomy and weight of reproductive tissues were compared to test the DEHP's effects on the cell proliferation. Furthermore, histological studies were performed to assess the structural alterations in the tissues. Specific radioimmunoassay was carried out to measure serum LH levels. To determine the transcriptional changes in progesterone receptor(PR), total RNAs were extracted and applied to the semi-quantitative reverse transcription polymerase chain reaction(RT-PCR). As a result, delayed VO was shown in the DEHP group(PND $37.3{\pm}0.7$) compared to the control group(PND $35.3{\pm}0.7$; p<0.05). DEHP treatment significantly decreased the wet weight of ovaries and uteri compared to the control group(p<0.05). Interestingly, elevation of serum LH levels was shown in the DEHP group(p<0.05). Graafian follicles and corpora lutea were observed only in the ovaries from the control animals. Numerous primary, secondary follicles and small atretic follicles were observed in the ovaries from DEHP-treated animals. Similarly, hypotrophy of luminal and glandular uterine epithelium was found in the DEHP-treated group. These effects were probably due to the inhibitory effects of DEHP on the synthesis and secretion of estrogen from granulosa cells. In the semiquantitative RT-PCR studies, the transcriptional activities of PR in both ovary(p<0.05) and uterus(p<0.01) from DEHP-treated animals were significantly lower than those from the control animals. The present studies demonstrated that the acute exposure to DEHP during the critical period of prepubertal stage could inactivate the reproductive system resulting delayed puberty in female rats.