• 한국임상약학회지
• /
• 제6권2호
• /
• pp.7-13
• /
• 1996

The purposes of this study were to define the pharmacokinetic parameters of vancomycin in Korean neonates, to evaluate current neonatal vancomycin dosing guideline being used in a teaching hospital, and to develop the optimal vancomycin dosing guideline. The evaluation of 35 sets of peak and trough concentrations drawn on current dosing regimen showed that $29\%$ of peak concentrations and $46\%$ of though concentrations were within therapeutic range. Otherwise, pharmacokinetic parameters, based on 62 sets of peak and trough serum concentrations obtained from 39 neonates, showed that mean vancomycin clearance (CL), volume of distribution (Vd), and terminal elimination half-life were $0.13\pm0.08\;L/hr,\;0.94\pm0.48\;L,\;and\;5.6\pm2.13$ hours, respectively. Volume of distribution (Vd) normalized for body weight remained constant throughout PCA range, whereas the absolute CL (r=0.74) and normalized CL (r=0.36) showed high correlation with PCA. Also, the normalized CL showed a strong inverse correlation (r=-0.55) with serum creatinine concentrations (SrCr). Based on the high correlation among PCA serum creatinine concentration, CL, and the daily dosage requirements, the following dosing guideline for vancomycin in neonates was suggested: 10 mg/kg $12{\sim}18$ hourly for < 30 weeks PCA and < 0.6 mg/dl SrCr; 10 mg/kg 18 hourly for < 30 weeks PCA and $0.6{\sim}1.2$ mg/dl SrCr; 10 mg/kg 8 hourly for $30\sim44$ weeks PCA and < 0.6 mg/dl SrCr; 10 mg/kg 12 hourly for $30\sim44$ weeks PCA and $0.6{\sim}1.2$ mg/dl SrCr.

• 한국토양비료학회지
• /
• 제50권5호
• /
• pp.383-390
• /
• 2017

Heavy metal contamination of soil might be a cause of serious concern due to the potential health impacts of consuming contaminated products. In this study, the total content of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn, As, and Hg) in soils was analyzed, and the difference of heavy metal contents depending on crops, soil characteristics, and topography was compared in 169 greenhouse soils obtained from Gyeongnam Province. The concentrations of the heavy metals were $0.25mg\;kg^{-1}$ (ranged 0.01~0.44) for Cd, $28.94(0.53{\sim}72.63)mg\;kg^{-1}$ for Cr, $26.03(0.5{\sim}166.13)mg\;kg^{-1}$ for Cu, $14.91(1.27{\sim}33.22)mg\;kg^{-1}$ for Ni, $15.76(0.43{\sim}57.1)mg\;kg^{-1}$ for Pb, $119.72(6.33{\sim}239.39)mg\;kg^{-1}$ for Zn, $2.54(0.01{\sim}23.57)mg\;kg^{-1}$ for As, and $0.049(0.012{\sim}0.253)mg\;kg^{-1}$ for Hg in topsoils. The concentrations of Pb and As in topsoil were highest in green pepper and those of Cd, Cr, and Ni were highest in melon. In addition, the concentrations of Cr and Ni were highest in diluvial terrace compared with the other topographies. Higher concentrations of Cd, Cr, and Ni were found in silty clay loam and silt loam soils than sandy loam and loam soils.

• 한국환경과학회지
• /
• 제11권7호
• /
• pp.713-720
• /
• 2002

In order to provide the basic information on the environmental pollution of Kyungsan province, the contents of Pb, Cd, Cr, Cu, Mn and Zn in soil, stream water, aquatic sediment and groundwater were investigated, and also the values of pH, COD, $KMnO_4-C$,\;NH_3-N,\;NO_2-N,\;NO_3-N$ and $Cl^-$ of stream water and groundwater were determined. The results were as follows. The values of COD, $NH_3-N,\;NO_2-N$ and $NO_3-N$ of the stream waters were very low. The contents of Pb, Cd, Cr, Cu and Zn in the stream waters were respectively at range of $0.014~0.063 mg/{\ell},\;0.004~0.007 mg/{\ell$\mid$, 0~0.045 mg/{\ell},\;0~0.008 mg/{\ell}$\;and\;$0.001~0.175 mg/{\ell}$, and these values were much lower than those of contaminated stream water in Korea. The contents of Cd, Cr, Cu and Zn in the soils were respectively at range of 0.12~O.71 ppm, 0.88~2.65 ppm, 2.86~22.33 ppm and 3.89~26.39 ppm, and these values were much lower than those of ordinary polluted areas in Korea. The contents of Cd, Cr, Cu, As, Zn and Mn in the aquatic sediments were respectively at range of 3.05~3.81 ppm, 14.6~70.6 ppm, 13.74~61.59 ppm, 76.8~465.5 ppm, 12.56~190.83 ppm and 333.3~l188.3 ppm. The values of pH, $KMnO_4-C,\;NH_3-N$, and $NO_3-N$ of the groundwaters were respectively at range of 7.6~8.4, $0~3.95{\ell}$, 0.05~0.15 mg/{\ell}$ and 0.05~0.42 $mg/{\ell}$. The contents of Pb, Cd and Cr in the groundwaters were respectively at range of 0.015~0.061 $mg/{\ell}$, 0.O06~0.009 $mg/{\ell}$ and 0.005~0.045 $mg/{\ell}$.

• 대한지역사회영양학회지
• /
• 제5권2호
• /
• pp.289-296
• /
• 2000

The purpose of this study was to investigate the relationship and lipids in healthy adults on self-selected diets. These subjects consisted of 40 female college students residing in Chungnam. Anthropometric measure-ments, diet intake measurements, and blood collection were conducted. Serum concentrations of 5 microminerals(As, Cr, Mn, Se, Ni), lipids(triglyceride, total cholesterol, HDL-cholesterol), and glucose were measured by an ICP spectrometer and biochemical analyzer. The results were as follows. The mean age of the subjects was 22.34 years and the mean weight, height, and BMI were 52.89kg, 161.29cm and 20.34, respectively. The mean serum concentrations appeared to be 14.60ug/dl(As), 1.87ug/dl(Cr), 0.18ug/dl(Mn), 23.50ug/dl(Se), 0.21ug/dl(Ni), 60.73mg/dl(triglyceride), 138.49mg/dl(total cholesterol), 65.95mg/dl(HDL-cholesterol), 60.39mg/dl(LDL-cholesterol) and 88.82mg/dl(glucose). When analyzed by Pearson’s correlation coefficient, the serum concentration of Cr was negatively correlated with Ca and vitamin B12 intake(p〈0.05, p〈0.05) respectively, Mn was negatively correlated with Na intake(p〈0.05), Ni, however, was positively correlated with K intake(p〈0.05). The serum concentration of Se was positively correlated with LDL-cholesterol(p〈0.05), Ni, however, negatively correlated with total cholesterol, HDL-cholesterol, LDL-cholesterol, and glucose, respectively(p〈0.001, p〈0.01, p〈0.05). Further studies are needed to clarify the precise micromineral intakes, nutritional assessment of microminerals, and cause-effect relation of microminerals and serum lipids.

• 한국위성정보통신학회논문지
• /
• 제7권1호
• /
• pp.39-47
• /
• 2012

현재의 주파수 분배상황을 살펴보면 대부분의 주파수 대역이 고정 할당되어 있으며 특히 무선통신 환경에 가장 적합한 저주파 대역은 거의 사용할 여지가 없다. 이에 인지무선 기술은 무선통신환경에서 주파수 부족 문제를 해결하고 주파수 활용도를 높이기 위한 중요한 기술로 대두되고 있다. 본 논문에서는 SDR (Software Define Radio)플랫폼인 USRP (Universal Software Radio Peripheral) 보드와 SDR 개발 툴킷인 GNU Radio를 이용하여 실제 인지무선(Cognitive Radio : CR) 시스템에서 데이터를 송, 수신하였다. 구체적으로 스펙트럼 센싱 기술을 이용하여 면허 사용자의 주파수 사용 여부를 감지하여 이 정보를 데이터베이스로 넘겨준다. 정보를 넘겨받은 데이터베이스에서는 유전자 알고리즘을 이용하여 최적의 송신전력과 대역폭, 채널 정보를 인지무선 기기에 보내어 주어 인지무선 기기가 면허 사용자에게 아무런 간섭을 주지 않고 데이터 통신을 할 수 있도록 하였다.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 1991년도 추계학술대회 논문집
• /
• pp.37-39
• /
• 1991

This paper is studies the effects of additives on the magnetic properties of Sr-ferrite. The specimens have been composed of SrO and Fe$_2$O$_3$with ratio of 1:5.9. As 1st additives, it is mixed to 0.2wt%, 0.7wt% and 1wt% of CaCo$_3$with 0.3wt% SiO$_2$. As 2nd addition, it is mixed to 0.5wt%, 1wt% of Na$_2$SiO$_3$, 0.5wt%, 1wt% of Cr$_2$O$_3$and 0.5wt%, 1wt% of Al$_2$O$_3$and sintering conditions was carried out at 1210$^{\circ}C$, 1230$^{\circ}C$ and 1250$^{\circ}C$. From experiments on the magnetic properties of specimen, the results were shown follows; (1) In case of additive SiO$_2$and CaO, it is stable magnetoplumbite structure for liquid phase grown, enhances mignetic propertics. (2) In case of basic compositions + 0.5wt% Al$_2$O$_3$, it is confirmed better properties by increasing of the coercivity than 0.5wt% Cr$_2$O$_3$additives. (3) In case of mixed additives of Cr$_2$O$_3$and Al$_2$O$_3$, magnetic propeties decrease with sintering density.

• 한국가축번식학회지
• /
• 제18권1호
• /
• pp.7-13
• /
• 1994

To verify in vivo viability of IVF-derived bovine embryos, morula and blastocysts that developed from in vitro matured and fertilized ova were transferred to the uteri of recipient cows and normal calves were produced. To produce IVF-derived bovine morula or blastocysts, ova matured and fertilized in vitro were cultured in culture medium for 7~8 days at 39$^{\circ}C$ under the humicified atmosphere of 5% CO2. Two different culture systems, a co-culture system with TCM-199 and bovine epithelial cells (BOEC) and CR1aa without somatic cell support, were compared. Cleavage rates to 2~8 cell stage and developmental rates of IVF-derived bovine embryos to blastocyst stage were not different between co-culture system (51.3 and 14.0%) and CR1aa medium (60.4 and 22.1%), respectively. Embryos were classified into three grades by embryo quality and then one or two embryos in higher quality(A and B grades) were transferred to the uterus of recipients. In this study Korean Native calf was first born after transfer of IVF-derived embryos. Total four live calves were normally developed to term from IVF-derived bovine blastocysts and one female fetus was still-born approximatedly 8 months of gestation, but there was no pregnancy after transfer of morula. Therefore, normal calves could be produced after transfer of IVF-derived bovine embryos cultured in CR1aa medium without somatic cell support. In addition, our results suggest that in transfer of IVF-derived bovine embryos blastocyst stage is better than morula.

• Earthquakes and Structures
• /
• 제7권1호
• /
• pp.39-55
• /
• 2014

A modified procedure is presented for assessing the seismic response of elastic non-proportionate multistory buildings. This procedure retains the simplicity of the methodology presented by the author in earlier papers, but it presents higher accuracy in buildings composed by very dissimilar types of bents. As a result, not only frequencies and peak values of base resultant forces are determined with higher accuracy, but also the location of the first mode center of rigidity (m1-CR). The closeness of m1-CR with the axis passing through the centers of floor masses (mass axis) implies a reduced rotational response and it is demonstrated that in elastic systemsa practically translational response is obtained when this point lies on the mass axis.Besides, when common types of buildings are detailed as planar structures under a code load, this response is maintained in the inelastic phase of their response as a result of the almost concurrent yielding of all the resisting bents. This property of m1-CR can be used by the practicing engineer as a guideline to form a structural configuration which will sustain minimum rotational response, simply by allocating the resisting elements in such a way that this point lies close to the mass axis. Inelastic multistory building structures, detailed as above, may be regarded as torsionally balanced multistory systems and this is demonstrated in eight story buildings, composed by dissimilar bents, under the ground motions of Kobe 1995 (component KJM000) and Friuli 1976 (component Tolmezzo E-W).

• 통상정보연구
• /
• 제9권3호
• /
• pp.273-284
• /
• 2007

New retailers, especially giant retailers, so called "mart" or "discounter" which introduced around 1996, when Korea's domestic retail market was opened to the world, have brought big transitions. Consequently, new comers like discounters and CVS drove out department stores, mom & pops and traditional retailers. Literatures showed two reverse opinions for the giant retailers; rising consumers' benefit, or dropping small retailers' businesses. This study have conducted to find the situation of market concentration in retail market, and to learn the new market condition in it. According to the study, in 2005, CR3's of Korea's whole retail industry was counted 12.8%, and CR5 of that was 13.9%. CR3 of discount store business was 39%, department stores' 55%, and TV home shopping businesses' was 75%. In addition to those results, indices growing worse. So, we can say this industry already get into the oligopolistic industrial organization. Generally, under monopolistic or oligopolistic market structure, consumers' benefit may shrink and businesses' surplus profit may jump. So, it means, it's good time to turn government's policy for the retail industry in Korea to fair competition policy instead of development policy.

• 상하수도학회지
• /
• 제20권6호
• /
• pp.867-874
• /
• 2006

The goal of this study is to assess cast iron pipes (CIPs) and present a residual tensile strength prediction model using pit characteristics and fracture toughness. The results is the followings. First, average pit depths of collected CIPs were in the range from 0.63 to 6.49 mm, loss of tensile strength compared with net metallic tensile strength were from -7.06 to 67.91 percent. Second, fracture toughness for NS-CR-1, NS-CR-2, and NS(2)-CR-1 were in the range from 62.85 to $89.39kgf/mm^2{\sqrt{mm}}$, and average of those samples was $73.69kgf/mm^2{\sqrt{mm}}$ on CIPs. Third, the models developed in this study by using pit characteristics and fracture toughness showed a little good correlation for measured residual tensile strength, and the results will be expected to help for water utilities to manage CIPs in the aspect of rehabilitation and assessment of structural safety on CIPs.