• Journal of the Korean Chemical Society
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• v.41 no.9
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• pp.449-459
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• 1997

The bonded state polarizabilities of ions in the alkali halides are estimated by using the Seitz and Ruffa (SR) energy level analysis relation. The effective number of electrons $(N_{eff})$ in the Slater-Kirkwood formula are used for all members of an isoelectronic sequence. The effective dispersion coefficients $(C_6^{eff})$ are calculated by the use of the empirical formula (J. Chem. Phys. 1991, 95, 1852) estimating $(N_{eff})$ values to reproduce the experimental $(C_6^{eff})$ for atom-atom (or molecule) interactions. In the framework of the T-Rittner model the model potential is constructed and used to calculate the values of dissociation energy and dipole moment. The results obtained in the present study are in good agreement with the experiment one.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.42 no.4 s.304
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• pp.11-16
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• 2005

Class area is a portion of memory where the constants, fields, and codes of the classes loaded into the Java virtual machine are kept. Knowing the size of the class area is very important especially for embedded Java system with limited memory resources. This paper induces a formula which makes it possible estimate the size of the area. The formula needs some constant values specific to target JVM implementation. We also show that these values can be found using some simple probe classes. An experimental result is included in this paper to confirm the correctness of our approach.

• Corrosion Science and Technology
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• v.9 no.3
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• pp.105-108
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• 2010

The product specification of the Continuous Hot Dip Galvanizing Line (CGL) changes and varies constantly with different customers' requirements, especially in the zinc coating weight which is from 30 to 150 g/$m^2$ on each side. Since the coating weight of zinc changes often, it is very important to reduce time spent in the transfer of target values changed for low production cost and yield loss. The No.2 CGL in China Steel Corporation (CSC) has improved the control of the air knife which is designed by Siemens VAI. CSC proposed an experiment design which is an $L_9(3^4)$ orthogonal array to find the relations between zinc coating weight and the process parameters, such as the line speed, air pressure, gap of air knife and air knife position. A non-linear regression formula was derived from the experimental results and applied in the mathematical model. A new air knife feedforward control system, which is coupled with the regression formula, the air knife control system and the process computer, is implemented into the line. The practical plant operation results have been presented to show the transfer time is obviously shortened while zinc coating weight target changing and the product rejected ratio caused by zinc coating weight out of specification is significantly reduced from 0.5% to 0.15 %.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.8
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• pp.633-641
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• 2008

Recently, the necessity for diagnosis and management of pipes has emerged as the issue due to contamination of water supply generated by corrosion of pipes. Although inspection has been performed with industrial endoscopes, the method has limits for full diagnosis of pipes due to the lack of working range. As a solution for this problem, many locomotive mechanisms for a micro robot with endoscope functions were proposed. In this paper, we analyze the locomotive mechanism of crawling robot proposed as locomotive device for pipe inspection. Based on a mechanical modeling of motor and micro robot inside small pipe, the theoretical formula for velocity is obtained. This derived theoretical formula is demonstrated the feasibility through the comparison with experimental result. Also, we could find the most important element influencing the moving velocity of micro robot when the robot operates in small pipe. Consequently, it is expected that this study can supply useful information to design of crawling robot to move in small pipe.

• 유체기계공업학회:학술대회논문집
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• 1998.12a
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• pp.42-48
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• 1998

Numerical study is presented for the analysis of three-dimensional incompressible turbulent flows in multiblade centrifugal fan. Reynolds-averaged Navier-Stokes equations with standard k - $\epsilon$ turbulence model are transformed to non-orthogonal curvilinear coordinates, and are discretized with finite volume approximations. Linear Upwind Differencing Scheme(LUDS) is used to approximate the convection terms in the governing equations. SIMPLEC algorithm is used as a velocity-pressure correction procedure. The computational area is divided into three blocks; core, impeller and scroll, which are linked by multi-block method. The flow inside of the fan is regarded as steady flow, and mathematical formula established from the cascade theory and empirical coefficient are employed to simulate tile flow through the impeller. From comparisons between the computational results and the experimental data, the validity of the mathematical formula for the blade forces was examined and good results were obtained qualitatively. Hence, we can get the flow characteristics of multi-blade centrifugal fan and it will be a corner stone of the development of the multiblade centrifugal fan.

• Herbal Formula Science
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• v.6 no.1
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• pp.215-226
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• 1998

Geagibokrounghwan (桂技茯笭湯) has long been used to cure human diseases such as vascular and blood disorders. However, it is still unkown on its action mechanism, physiolosical and biochemical meaning. Thus, many attempts were tried to show the scientific background covering the above mentioned mechanism. The effect of Geagibokrounghwan, which was known to date, as follow; effective circulation of body blood system, proliferation of leucocytes and antioxidative action. In this study, we have applied the Geagibokrounghwan administration and feed to mouse, to see effects on the expression of superoxide dismutase(SOD) mRNA as antioxidative agent and oxygen radical scavenger. Total RNAs includingmRNA have been isolated from liver and white blood cells after mice were fed with cholesterol in high dose. Also, in a separate group, the cholesterol-administrated mice were fed with Geagibokrounghwan to see the effects on SOD transcription. and then reverse transcriptase-polymerase chain reaction (RT-PCR) usion each primer set (SOD-F;GATGAAAGCGGTGT-3'; SOD-R; 5'-CCTGTGGAGTGATT-3') were performed to trace theamounts of mRNA. SOD mRNA was specifically expressed in Geagibokrounghwan-fed mice at 2 weeks after treatment, however, gradually reduced after 4 weeks. These results indicate that Geagibokrounghwan is highly applicable in treatment of the above mentioned human diseases.

• Herbal Formula Science
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• v.10 no.1
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• pp.93-103
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• 2002

This experimental studies were done to investigate the effects of Sambutang(SBT) and consitituent herbs on the regional cerebral blood flow(rCBF) and mean arterial blood pressure(BP) in rats. The results are as follows: SBT and consitituent herbs(SBT omitting Zingiberis Rhizoma Recens, Zingiberis Rhizoma Recens. Ginseng Radix and Aconiti iateralis preparata Radix) was increased rCBF significantly in a dose-dependent manner. SBT omitting Zingiberis Rhizoma Recens and Ginseng Radix were decreased significantly BP in rats. But, SBT, Aconiti iateralis preparata Radix and Zingiberis Rhizoma Recens were not affected BP in rats. According to the above findings. it is suggested that SBT causes a diverse response of rCBF, and specially the rCBF by increasing SBT is mediated action of Zingiberis Rhizoma Recens.

• Herbal Formula Science
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• v.10 no.1
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• pp.61-72
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• 2002

This present study was carried out to investigate the body weight-regulatory effects of Glechoma longituba in high fat diet-induced obese rats. Control group rats were fed with high fat diet and administered normal saline for 8weeks. Experimental groups rats were fed with high fat diet and administered extract of Glechoma longituba for 8 weeks. And observed that, body weight of rats and total cholesterol, triglyceride, free fatty acid, phospholipid in serum of rats. The results were as follows: 1. There were decrease of body weight of rats in GL group, but these results showed no significant efficacy. 2. There were significant decrease of serum total cholesterol level in GL group. 3. There were decrease of serum triglyceride level in GL group, but these results showed no significant efficacy. 4. There were decrease of serum free fatty acid level in GL group. but these results showed no significant efficacy. 5. There were significant decrease of serum phospholipid level in GL group. According to above mentioned results, Glechoma longituba is expected to be applied to the prevention or treatment of obesity and its complications.

• Herbal Formula Science
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• v.12 no.2
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• pp.109-117
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• 2004

This study was carried out to investigate the liver protective effects of extracts from Persicae Semen (WT-003, WT-005, WT-006). The acute hepatic injury was induced by intraperitoneal injection of alpha-naphtylisothiocyanate (75 mg/kg, p.o.) and treated with WT-006 (100 mg/kg/day, 200 mg/kg/day, 400 mg/kg/day). The experimental hepatic fibrosis was induced by bile duct ligation／scission(BDL/S), duration of 4 weeks and treated with WT-003, WT-005 or WT-006 (200 mg/kg/days for 4 week). In acute liver injury, WT-006 (200 or 400 mg/kg) lowered serum alanine transferase(ALT) and aspartate transferase(AST) significantly. In fibrotic rats, WT-006 treatment inhibited the hydroxyproline deposition in liver and lowered serum AST, ALT and ALP, significantly. These results suggest WT-006 extract, which does not contain amygdalin, from Persicae Semen have liver protective and antifibrotic effects in rats.

• Herbal Formula Science
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• v.8 no.1
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• pp.129-146
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• 2000

This study was carried out to investigate the effects of Solanum lyratum Extract (SLE) on the recovery of liver in $CCI_{4}-intoxicated$ mice. In this study, ICR-Mice were divided into 3 experimental groups; Normal group was fed basal diet and was fed bassal diet for 2 Weeks, sample group was injected $CCl_{4}\;(0.6m{\ell}/kg)$ and was fed basal diet for 2 weeks, sample group was injected $CCl_{4}\;(0.6m{\ell}/kg)$ and was fed the SLE 500mg/kg fod 2 Weeks. In sample group, the level of serum AST, ALT, ALP activity decreased significantly compared with control group. This results suggest that SLE has appreciable therapeutic effect on $CCI_4$ induced hepatotoxicity. In sample group, the level of LPO in liver homogenates decreased significantly compared with control group. In sample group. the level of GSH, catalase in liver homogenates increased significantly compared with control group. This results suggest that SLE has appreciable antioxidant effect on $CCI_4induced hepatotoxicity. In conclusion the results suggest that SLE has appreciable therapeutic effect and antioxidant effect on $CCI_4$ induced hepatotoxicity.