• Magazine of the Korean Society of Agricultural Engineers
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• v.44 no.1
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• pp.69-80
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• 2002

This study aims to develop a potential centrality evaluation model (PCEM) which can evaluate the potential centrality of villages within the catchment boundaries. PCEM is a tool for evaluation of villages\` centralities by the potential centrality index (PCI) developed in this study. For quantification of PCI, total 31 evaluation criteria on the accessibility to other villages and the natural and human environment of the village were introduced. The weighting values of criteria were calculated from the step wise pair-comparision results of 14 specialists in academic fields on rural planning using by AHP (Analytic Hierachy Process) of MCE (multi-criteria evaluation) method. In the results, the weighting values of the spatial accessibility, the natural environments and the human environments were 448, 338 and 214, respectively, among total value being 1,000.

• Corrosion Science and Technology
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• v.11 no.6
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• pp.247-256
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• 2012

Harmonic current was measured for a dummy cell with various values of resistance, and the procedure developed through the measurements was applied to the investigation of effects of the amplitude of applied frequency and applied potential on the harmonic current of a stainless steel and a carbon steel in chloride containing solutions. From the measurements of harmonic current in the dummy cell, the optimum values of applied frequency and applied potential in harmonic current measurements were found to be 1 mHz and 20 mV (or lower), respectively. Increase in harmonic current with applied frequency was observed in the case where the level of harmonic current is low as in a stainless steel. Decrease in polarization resistance was also noted in this corrosion system with either increasing applied frequency or decreasing applied potential. However, no obvious effects of applied frequency was observed on harmonic current and polarization resistance in a carbon steel in which the level of harmonic current is high.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.5
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• pp.841-848
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• 1987

This paper presents a new two-stage edge detection algorithm which can give thin edges and can find edges between low contrast regions. In the first stage, the potential edge points are obtained using the proposed edge operator which is motivated by the concept of the E filter. And in the second stage, the real edge points adre detected by comparing the potential edge values with the lically adaptive threshold values of the corresponding potential edge points and by testing whether the potential edge points are zero-crossing points or not. It is shown quantitatively that the proposed algorithm can find edges effectively in an image with impulse noise, and also the results of applying the proposed algorithm to real images are presented.

• Korean Journal of Metals and Materials
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• v.46 no.1
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• pp.20-25
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• 2008

The ionic equilibira in mixed solutions of cuprous and cupric chloride were analyzed by considering chemical equilibria, mass and charge balance equations. The activity coefficients of solutes were calculated by using Bromley equation. Required thermodynamic constants and interaction parameters were evaluated from the data reported in the literature. The effect of NaCl and CuCl concentrations on the pH and potential of the mixed solutions was explained in terms of the variation in the concentration of solutes and in the activity of hydrogen ion. The calculated pH values of the mixed solutions agreed well with the measured values. However, the calculated values for the potential of the mixed solutions were lower than the measured values, indicating the necessity of considering the complex formation between cuprous and chloride ion, such as $Cu^2Cl{_4}^{2-}$ and $Cu_3Cl{_6}^{3-}$.

• Bulletin of the Korean Chemical Society
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• v.2 no.1
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• pp.17-24
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• 1981

Thermodynamic properties such as sublimation pressures, enthalpies and entropies of sublimation, enthalpies and entropies of solid krypton and xenon are calculated from $0{\circ}K$ to the triple point, using the vacancies-in-solid model. The Mie-Lennard-Jones 12,6 potential in uniform potential field is used. The results are compared with the calorimetric and sublimation pressure values, and are in a good agreement with the available calorimetric and sublimation pressure values.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.3
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• pp.173-183
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• 2000

This study measured the zeta potential of both latex colloidal particles with carboxylate surface groups and glass beads (collectors) with silanol surface group employing various solution with different chemical characteristics. The results have been compared with the surface chemistry theory. The zeta potential of the particle and collector increased with increasing pH up to 5.0 regardless of the solution chemistry. For a monovalent electrolyte solution(sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (sodium chloride solution) the zeta potential steadily increased until the pH reached 9.5. In contrast, little change in zeta potential was made between 5.0 and 9.5 for a divalent electrolyte solution (calcium chloride solution). In other words, the more the pH decreases, the larger the effect of neutral salts, such as NaCl and CaCl$_2$, have on the ζ-potential values. In this study, the PZPC(point of zero proton condition) of the particle and collector occurred below a pH of 3.1, H(sup)+ and OH(sup)- acted as a PDI (potential determining ion), and Na(sup)+ acted as an IDI(indifferent ion). The magnitude of the negative ζ-potential values of the particle and collector monotonically increased as the concentrations of Na(sup)+ or Ca(sup)2+([Na(sup)+] or [Ca(sup)2+]) decreased (the values of pNa or pCa increased). In the case of latex particles, the ζ-potential should aproach zero (isoelectric point; IEP) asymptotically as the pNa approaches zero, while in the case of calcium chloride electrolyte, ζ-potential reversal may be expected to occur around 3.16$\times$10(sup)-2MCaCl$_2$(pCa=1.5). pH, valance and ionic strength can be used in various ways to improve the water treatment efficiency by modifying the charge characteristics of the particle and collector. Predictive capability is far less certain when EDL(electrical double layer) repulsive forces exist between the particle and collector.

• Journal of Korean Society of Rural Planning
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• v.13 no.2
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• pp.7-16
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• 2007

This study aims to develop an evaluation method of green-tourism potential in village level with amenity resources of rural villages, considering human resources of the village. The amenity resources evaluation system was classified into three sub-classes with social, industrial, and natural resources. The system consisted of a relationship diagram between three classes resources and tourists' behavior. The new methodology considers human resources as a key factor for green-tourism potential evaluation of villages, including the amenity resources of three sub-classes. In quantitative method for the criteria, this study adopted a new method of continuous linear score method, which is applying fuzzy theory, not to give score with the existing discrete scoring method with several steps. The weighting values of the evaluation criteria were calculated from the step wise pair-comparision results by AHP(Analytic Hierachy Process) method, which industrial, natural, and social resources have relative weighting values of 523/1000, 319/1000, and 158/1000, respectively. In evaluation of another weighting value by the same methodology, the results showed that the amenity and the human resources have weighting values of 627/100 and 373/1000, respectively. The new evaluation method was applied to make the potential evaluation for rural villages of the study area, which located on Narial-myun, Keumsan-gun, Chungnam province. The development priority among the villages could be suggested reasonably by the new findings of this study, according to the evaluation results showing that the village with high possibility for development in green-tourism has high score in the potential evaluation.

• Journal of Microbiology and Biotechnology
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• v.30 no.6
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• pp.893-902
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• 2020

Propolis is a resinous substance that is collected by Apis mellifera from plant sources and is used in traditional medicine. To study the phytochemical constituents and apoptotic potential of Jordanian propolis extract against different cancer cell lines, propolis was extracted using methanol, hexane, and ethyl acetate and was fractionated using chromatographic methods. Cytotoxicity was assessed using MTT and LDH assays. The apoptotic potential was investigated using florescence microscopy, multicaspase assay, Annexin-V and dead cell assay, and cell cycle assay. The phytochemical constituents were analyzed using GC-MS. The methanol extract of propolis exhibited cytotoxic potential against all cell lines tested. The IC₅₀ values of the methanol extract were 47.4, 77.8, 91.2, and 145.0 ㎍/ml for HepG2, LoVo, MDAMB231, and MCF7 cell lines, respectively. The IC₅₀ values of the F1 fraction were 31.6 (MDAMB231), 38.9 (HepG2), 36.7 (LoVo) and 75.5 (MCF7) ㎍/ml. On further purification using thin-layer chromatography, the IC₅₀ values of the F1-3 fraction were found to be 84.31(HepG2), 79.2 (MCF7), 70.4 (LoVo), and 68.9 (MDAMB231) ㎍/ml, respectively. The anticancer potential of the F1 fraction was confirmed through the induction of apoptosis and cell cycle arrest at the G0/G1 phase. The GC-MS analysis of the F1 fraction revealed the presence of 3-methyl-4-isopropylphenol (29.44%) as a major constituent. These findings indicate the potential of propolis extract as a cancer therapy. However, further investigation is required to assess the acute and subacute toxicity of the most active fraction.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.6
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• pp.811-816
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• 2000

Five experiments were conducted to evaluate blood urea nitrogen (BUN) as a potential index of feed efficiency (G/F) and lean growth in growing-finishing pigs. Exp. 1 was conducted to examine the relationship between feeding protocol and BUN values. Fasted-refed pigs exhibited BUN peaks 3 h post-prandially while those given ad libitum access to diet had inconsistent BUN patterns in 10 h blood sampling with an 1 h interval. In Exp. 2 and 3, it was revealed that the peak BUN values were negatively correlated (p<0.01) with G/F in both barrows and gilts at 20 kg body weight (BW) and 50 kg to 90 kg BW. In Exp. 4, it was found that BUN values between 55 kg and 70 kg BW, when lean gain is maximized, were best correlated with average daily lean gain (ADLG). In Exp. 5, 18 barrows and 21 gilts were used to examine the relationship between BUN values at 65 kg BW and ADLG from birth to market weight. The BUN values at 65 kg BW and ADLG were negatively correlated (p<0.01) in both genders. These experiments demonstrated that there was a correlation between peak BUN values, and G/F and ADLG under specific circumstances.

• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3425-3428
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• 2013

We solve the Klein-Gordon equation with the Morse empirical potential energy model. The bound state energy equation has been obtained in terms of the supersymmetric shape invariance approach. The relativistic vibrational transition frequencies for the $X^1{\sum}^+$ state of ScI molecule have been computed by using the Morse potential model. The calculated relativistic vibrational transition frequencies are in good agreement with the experimental RKR values.