• Journal of the Computational Structural Engineering Institute of Korea
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• v.31 no.6
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• pp.331-337
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• 2018

This paper presents dynamic algorithm of the MLS(moving least squares) difference method using first order differential Approximation. The governing equations are only discretized by the first order MLS derivative approximation. The system equation consists of an assembly of the approximate function, so the shape of system equation is similar to FEM(finite element method). The CDM(central difference method) is used for time integration of dynamic equilibrium equation. The natural frequency analyses of the MLS difference method and FEM are performed, and two analysis results are compared. Also, the accuracy of the proposed numerical method is verified by displaying the dynamic analysis results together with the results by the existing second order differential approximation. In the process of assembling the first order MLS derivative approximation, the oscillation error was suppressed and the stress distribution was interpreted as relatively uniform.

• Journal of the Korean Mathematical Society
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• v.49 no.3
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• pp.537-547
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• 2012

In this paper, we define a $p$, $q$-difference operator and obtain an explicit formula which is used to express the $p$, $q$-analogue of the unified generalization of Stirling numbers and its exponential generating function in terms of the $p$, $q$-difference operator. Explicit formulas for the non-central $q$-Stirling numbers of the second kind and non-central $q$-Lah numbers are derived using the new $q$-analogue of Newton's interpolation formula. Moreover, a $p$, $q$-analogue of Newton's interpolation formula is established.

• Journal of Electrochemical Science and Technology
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• v.9 no.2
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• pp.99-108
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• 2018

Proton exchange membrane (PEM) water electrolysis systems offer several advantages over traditional technologies including higher energy efficiency, higher production rates, and more compact design. In this study, all the experiments were performed with a self-designed PEM electrolyser operated at 1 atm and $25^{\circ}C$. Two types of electrolyte were used: (i) potassium hydroxide (KOH), and (ii) sulfuric acid ($H_2SO_4$). In the experiments, the voltage, current, and time were measured. The concentration of the electrolyte significantly affected the electrolyser performance. Overall the best case was with 15 wt% $H_2SO_4$ at the anode channel and 20 wt% at the cathode channel with. In addition, increasing the difference in concentration of the sulfuric acid had an effect on the diffusion. The diffusion flux became larger when the difference in concentration became larger, increasing electrolyser efficiency without the addition of extra energy.

• Journal of computational fluids engineering
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• v.11 no.1 s.32
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• pp.36-42
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• 2006

The existing numerical approximations of convection flux, especially the spatial higher-order difference schemes, in unstructured cell-centered finite volume methods are examined in detail with each other and evaluated with respect to the accuracy through their application to a 2-D benchmark problem. Six higher-order schemes are examined, which include two second-order upwind schemes, two central difference schemes and two hybrid schemes. It is found that the 2nd-order upwind scheme by Mathur and Murthy(1997) and the central difference scheme by Demirdzic and Muzaferija(1995) have more accurate prediction performance than the other higher-order schemes used in unstructured cell-centered finite volume methods.

• International Journal of Industrial Entomology and Biomaterials
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• v.7 no.1
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• pp.15-20
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• 2003

The present investigation was carried out to study the possible cause for reciprocal difference in silkworm hybrids. By utilising the polyvoltine race Pure Mysore (PM) and newly evolved breeds (CSR2, CSR5, CSR16 and CSR17), the direct and reciprocal crosses of polyvoltine ${\times}$ bivoltine and also bivoltine hybrids were studied. The hybrids of polyvoltine ${\times}$ bivoltine (direct) are superior to their reciprocal crosses in respect of cocoon yield, cocoon weight and filament length. The reciprocal crosses of polyvoltine ${\times}$ bivoltine are superior to their direct crosses in respect of fecundity and short larval duration. No significant differences were observed in the characters like cocoon shell ratio, raw silk percentage, denier, reelability and neatness in both polyvoltine ${\times}$ bivoltine direct crosses and their reciprocals. The expression of cocoon characters as a function of sex revealed that direct crosses (polyvoltine ${\times}$ bivoltine) showed higher cocoon weight, pupal weight, shell weight and longer filament length in females than the reciprocal crosses (bivoltine ${\times}$ polyvoltine), where as these characters in males were almost the same in both direct and reciprocal crosses, indicating that the sex-linked genetic factor played a more important role. it was clear that difference in cocoon yield observed in reciprocal crosses of polyvoltine ${\times}$ bivoltine was due to the low cocoon and shell weight in females which was turn due to presence of early maturity genes (Lme) linked with sex-chromosome (X) which effect on larvae period of the silkworm. In bivoltine hybrids, i.e., both direct and their reciprocals crosses, all the characters viz., hatching percentage, larval duration, survival, cocoon weight, cocoon shell weight, cocoon shell ratio, raw silk percentage, filament length, denier, reelability and neatness did not show any significant difference (except number of eggs laid by moth) which could account for presence of same maturity genes (Lm) in both direct and reciprocal crosses. it was clear that reciprocal differences occur when the hybrids are prepared from the parental strains with different voltinism.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.5
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• pp.633-636
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• 2002

Six adult Garole rams maintained under a semi-intensive system were used as semen donors for this study. Semen was collectied daily during the monsoon season with the help of an artificial vagina and examined for its quality characteristics. Ejaculates of thick consistency, rapid wave motion, ${\geq}80%$ motility and intense movement of motile spermatozoa were diluted at the rate of 1:1 with egg yolk McIllvaine glucose diluent at $30^{\circ}C$ in water bath. Estrus in ewes was detected by parading aproned rams of proven vigour at 12 h intervals. The ewes (54 Malpura and 23 Avikalin) in estrus were artificially inseminated with fresh diluted ram semen. The overall conception rate was 94.8%, (range 91.7 to 100%). The overall lambing percent was 80.5 with a range of 75.0 to 84.6%. There was no significant (p>0.05) difference in lambing and conception rate because of individual rams. Fertility was significantly lower (p<0.05) in ewes of less than two years and more than six years of age. Breed (Malpura and Avikalin) effect was not observed in conception and lambing rate (p>0.05). No significant difference (p>0.05) in birth weight and 12 month weight was observed between Garole${\times}$Avikalin and Garole${\times}$Malpura crossbred lambs but there was significant (p<0.05) difference at three month and six months body weight of both the crossbred lambs.

• Journal of Korea Entertainment Industry Association
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• v.14 no.8
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• pp.221-230
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• 2020

This study aimed to investigate the difference of sensory changes by central and peripheral stimulation for improving life care in chronic low back pain patients. Twelve chronic low back pain patients were randomly assigned to central stimulation (CS, n=6) and peripheral stimulation (PS, n=6). Quantitative sensory test (QST), pressure pain threshold (PPT) and Korean oswestry back pain disability index (KODI) were used to quantitatively measure and analyze. As a result, QST, PPT and KODI showed significant differences by period (p<.01) but did not showed any difference between the two groups (p>.05). Therefore, both stimulations had significant effects on increased sensory threshold and function improvement of the muscles that became sensitive due to pain. It is thought to be significant in improving life care for patients with chronic low back pain.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.12
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• pp.1675-1677
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• 2001

The effect of the presence or absence of corpus luteum in the ovaries of slaughtered buffaloes was studied for the oocytes recovery and their subsequent maturation and fertilization in vitro. On an average, 0.41 and 0.67 oocytes per ovary were recovered from ovaries with and without corpus luteum, respectively. Immature oocytes were matured in TCM-199 medium. Significant difference was observed in maturation rate between good (74%) and fair (37%) oocytes. However, there was no significant difference in cleavage rate between the two types. The results of this study show that although the presence of corpus luteum in the ovary at the time of recovery significantly affected availability of total oocytes and in-vitro maturation, but fertilization and cleavage remained unaffected under in vitro conditions.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.81-81
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• 2017

The origin of wild corn (teosinte) is distributed in the Northwest coastal pacific area of Central America, including Mexico, which is a wetland area of 5 to 6 months per year. Depending on these climate characteristics, wild corn is genetically resistant to flooding condition. In order to evaluate the availability of flooding resistant genes of these wild corns, we examined the physiological responses after the flooding treatment in the early stages of the growth of various wild corns. The difference of chlorophyll content between flooding untreatment and flooding treatments (untreated chlorophyll content - humidified chlorophyll content) was the highest in chlorophyll content in the case of B73, the common corn. In the middle leaf, $\underline{Zea}$ mays subsp. Parviglumis, Zea mays subsp. Mexicana, Zea mays subsp., Zea perennis decreased significantly. In the lower leaves, Zea mays sub and Zea nicaraguensis showed the lowest content compared to B73. PCR analysis was performed using 34 primers divided into two groups, top and bottom. In the wild corn, pyruvate decarboxylase 2 in root and alcohol dehydrogenase 1 in shoot showed the difference in the reaction.

• The Korean Journal of Physiology
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• v.19 no.2
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• pp.113-125
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• 1985

Electrophysiological difference of the central and peripheral area of the sinoatrial node in the rabbit was studied by glass microelectrode technique. Effects of $K^+,\;Na^+,\;Cs^+,$ adrenaline and ouabain on the action potential of the two areas were investigated, and transient hyperpolarization ($K^+-induced$ hyperpolarization) which developed following readmission of potassium after having pre-treated with $K^+-free$ Tyrode solution for 10 minutes was analyzed. The results obtained were as follows ; 1) The frequency of the spontaneous action potential recorded in the periphery of the SA node was faster than the central area. Reduction by $Cs^+$ and increase by O mM $K^+$, $10^{-6}M$ adrenaline and $10^{-6}M$ ouabain in the frequency of action potential were noticed more prominently in the peripheral than the central area. On the contrary, the frequency in the central area was more decreased than the Peripheral area by 13 mH $K^+$ and 1 mM $Co^{2+}$. 2) The amplitude of the K+_induced hyperpolarization was very small in the central area but large in the peripheral area. Transient hyperpolarization was abolished by ouabain and low sodium, and decreased by cooling the tissue $(17^{\circ}C)$. 3) By changing the concentration of $Ca^{2+}$ in the perfusate, the amplitude and the rate of transient hyperpolarization were increased in the high $Ca^{2+}$ concentration. It could be concluded that the central area of the SA node is less susceptible to the inhibition of Na-Pump and more susceptible to Ca-blocker and high concentration of $K^+$. The Na-Pump activity of the central area measured by means of transient hyperpolarization is found to be much less active than that of the peripheral area.