• The Journal of the Korea Contents Association
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• v.15 no.3
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• pp.192-198
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• 2015

Checked out by the moving vehicle health checks for patients, practitioners, and the increase in radiation dose outside the vehicle, but an investigation into the leakage of radiation can still be negligible. In this study, through experimental results were as follows: Dose that occurs most often where the leak in the right door $1.14{\pm}1.75mR/h$, X-ray generator in terms of proximity to the top $0.65{\pm}1.25mR/h$, X-ray generator and away to the bottom in terms $0.91{\pm}1.25mR/h$, the adjacent rear detector in the upper part $96.98{\pm}158.88mR/h$ dose of the leak appeared in various locations. By measuring position from the rear of the adjacent detector $67.48{\pm}97.03mR/h$ dose had the highest leakage into. Generating device for diagnosis of radiation safety regulations regarding the maximum leakage dose per week, but all met back when it is displayed in the leakage dose Hourly rates do not ignore the leakage radiation dose were measured. Therefore, a mobile health screening in a vehicle outside of the leakage radiation dose to the liver and move on we are not interested twelve barrier leakage radiation dose of defense has a chance to re-evaluate the standards required, and move the vehicle health check using the X-ray increases as the dose per hour, depending on the criteria for choosing the appropriate measures that will require effort.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.2
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• pp.183-193
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• 1995

Assuming that fishing nets are porous structures to suck water into their mouth and then filtrate water out of them, the flow resistance N of nets with wall area S under the velicity v was taken by $R=kSv^2$, and the coefficient k was derived as $$k=c\;Re^{-m}(\frac{S_n}{S_m})n(\frac{S_n}{S})$$ where $R_e$ is the Reynolds' number, $S_m$ the area of net mouth, $S_n$ the total area of net projected to the plane perpendicular to the water flow. Then, the propriety of the above equation and the values of c, m and n were investigated by the experimental results on plane nettings carried out hitherto. The value of c and m were fixed respectively by $240(kg\cdot sec^2/m^4)$ and 0.1 when the representative size on $R_e$ was taken by the ratio k of the volume of bars to the area of meshes, i. e., $$\lambda={\frac{\pi\;d^2}{21\;sin\;2\varphi}$$ where d is the diameter of bars, 21 the mesh size, and 2n the angle between two adjacent bars. The value of n was larger than 1.0 as 1.2 because the wakes occurring at the knots and bars increased the resistance by obstructing the filtration of water through the meshes. In case in which the influence of $R_e$ was negligible, the value of $cR_e\;^{-m}$ became a constant distinguished by the regions of the attack angle $ \theta$ of nettings to the water flow, i. e., 100$(kg\cdot sec^2/m^4)\;in\;45^{\circ}<\theta \leq90^{\circ}\;and\;100(S_m/S)^{0.6}\;(kg\cdot sec^2/m^4)\;in\;0^{\circ}<\theta \leq45^{\circ}$. Thus, the coefficient $k(kg\cdot sec^2/m^4)$ of plane nettings could be obtained by utilizing the above values with $S_m\;and\;S_n$ given respectively by $$S_m=S\;sin\theta$$ and $$S_n=\frac{d}{I}\;\cdot\;\frac{\sqrt{1-cos^2\varphi cos^2\theta}} {sin\varphi\;cos\varphi} \cdot S$$ But, on the occasion of $\theta=0^{\circ}$ k was decided by the roughness of netting surface and so expressed as $$k=9(\frac{d}{I\;cos\varphi})^{0.8}$$ In these results, however, the values of c and m were regarded to be not sufficiently exact because they were obtained from insufficient data and the actual nets had no use for k at $\theta=0^{\circ}$. Therefore, the exact expression of $k(kg\cdotsec^2/m^4)$, for actual nets could De made in the case of no influence of $R_e$ as follows; $$k=100(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})\;.\;for\;45^{\circ}<\theta \leq90^{\circ}$$, $$k=100(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})^{1.6}\;.\;for\;0^{\circ}<\theta \leq45^{\circ}$$

• Journal of the Korean Chemical Society
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• v.30 no.3
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• pp.273-281
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• 1986

This study is focused on the correct measurement of the equations for the determination of the impedance parameters-the differential capacity of the double layer $C_d$, solution resistance $R_Q$, transfer resitance $R_i$, and adsorption pseudcapacity $C_{\phi}$/ The application of only an imaginary part of complex function of ${\omega}$ at the sinusoidal steady state indicates the following equations of total impedance: at low frequency $|Z_{LF}|=1/{\omega}_1\;C_{\phi}\;{\sqrt{1+{{\omega}_1}^2/{\omega}^2}$, at high frequency $|Z_{HF}|={\omega}_2/({\omega}_1{\omega}_3C{\phi})({\omega}^2+{{\omega}_2}^2)\;{\sqrt{{({\omega}^2+{\omega}_2{\omega}_3)}^2+{({\omega}_2{\omega}-{\omega_3{\omega})^2}}$. The values of the total impedance of cell, phase angle, and cell current that are necessary for the calculations of impedance parameters were experimentally measured from 200 to 6000Hz for the following supporting electrolytes, 0.5M $Na_2SO_4$, 1M NaCl, 19.373% sea water, 1M HCl, 1M $KNO_3$ and for $10^{-2}M$ KI and 60mM DBNA (Di-iso-Butylnitrosoamine) in these supporting electrolytes. The derived equations in this study shows that the values of impedance parameters of $C_d,\;C_{\phi},\;R_i\;and\;R_Q\;are\;15{\sim}40\;{\mu}F/cm^2,\;162{\sim}758\;{\mu}F/cm^2\;11.5{\sim}57.6\;ohm{\cdot}cm^2\;and\;0.5{\times}10^{-2}{\sim}4.1{\times}10^{-2}\;ohm{\cdot}cm^2$ respectively.

• Bulletin of the Korean Mathematical Society
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• v.57 no.2
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• pp.407-417
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• 2020

Let (R, m) be a d-dimensional Cohen-Macaulay local ring with infinite residue field. Let I be an ideal of R that has analytic spread ℓ(I) = d, satisfies the G_d condition, the weak Artin-Nagata property AN^-_d-2 and m is not an associated prime of R/I. In this paper, we show that if j₁(I) = λ(I/J) + λ[R/(J_d-1 :_RI+(J_d-2 :_RI+I):_R m^∞)] + 1, then I has almost minimal j-multiplicity, G(I) is Cohen-Macaulay and r_J(I) is at most 2, where J = (x₁, _…, x_d) is a general minimal reduction of I and J_i = (x₁, _…, x_i). In addition, the last theorem is in the spirit of a result of Sally who has studied the depth of associated graded rings and minimal reductions for m-primary ideals.

• Transactions of the Korean Society of Mechanical Engineers
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• v.10 no.5
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• pp.645-652
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• 1986

For the analysis of equi-biaxial tension, the Lankford values at the various strain levels were measured experimentally at first. It was clarified that the R values depend on strain to a great extent and based on this result, the analysis of the equi-biaxial tension was carried out. Hill's new yield criterion was used to predict the stress-strain curves theoretically. The value of new parameter, m for the coincidence of the theory with the experiment was 2.1. It is desired that the optimum R-value in the case of m=2.1 is measured at strain, 15% for the reasonable correlation between theory and experiment.

• Journal of the Korean Mathematical Society
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• v.60 no.2
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• pp.327-339
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• 2023

Let R be a commutative ring with identity and S be a multiplicatively closed subset of R. In this article we introduce a new class of ring, called S-multiplication rings which are S-versions of multiplication rings. An R-module M is said to be S-multiplication if for each submodule N of M, sN ⊆ JM ⊆ N for some s ∈ S and ideal J of R (see for instance [4, Definition 1]). An ideal I of R is called S-multiplication if I is an S-multiplication R-module. A commutative ring R is called an S-multiplication ring if each ideal of R is S-multiplication. We characterize some special rings such as multiplication rings, almost multiplication rings, arithmetical ring, and S-P IR. Moreover, we generalize some properties of multiplication rings to S-multiplication rings and we study the transfer of this notion to various context of commutative ring extensions such as trivial ring extensions and amalgamated algebras along an ideal.

• Journal of Energy Engineering
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• v.15 no.4 s.48
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• pp.243-249
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• 2006

An experimental study on the refrigerant-side pressure drop of slit fin an tube heat exchanger has been carried out. A comparison was made between the predictions of previously proposed empirical correlations and experimental data for the pressure drop on design conditions of condenser in micro-fin tube for R22 and Rl34a. Experiments were carried out under the conditions of inlet refrigerant temperature of $60^{\circ}C$ and mass fluxes varying from $150\;to\;250\;kg/m^{2}s$ for R22 and Rl34a. The inlet air conditions are dry bulb temperature of $35^{\circ}C$, relative humidity of 40% and air velocity varying from 0.68 to 1.43 m/s. Experiments show that pressure drop for R134a was $22{\sim}22.6%$ higher than R22 for the degree of subcooling $5^{\circ}C$ For the mass fluxes of $200{\sim}250\;kg/m^{2}s$, the deviation between the experimental and predicted values for the pressure drop was less than ${\pm}20%$ for R22 and Rl34a.

• Korean Journal of Agricultural and Forest Meteorology
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• v.9 no.3
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• pp.203-208
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• 2007

The woody tissue respiration rates in stems ($R_{stem}$) of red pine (Pinus densiflora Sieb. et Zucc.) forest in Higashi-Hiroshima, west Japan, were measured using an open flow measurement system with several chambers in two seasons (the winter and summer in 2002). $R_{stem}$ ranged from 0.25 to $0.55{\mu}mol\;m^{-2}s^{-1}$ in winter, and from 1.25 to $1.63{\mu}mol\;m^{-2}s^{-1}$ in summer. The variability of $R_{stem}$ among the sampled trees (n=15) was similar between the two seasons, with the coefficient variation of about 23%. The numbers of sampling points required to estimate the stem respiration rate within 10 to 20% of its actual value were 24 and 6, respectively in both seasons (probability level is 95%). Based on the relationship between stem temperature and average $R_{stem}$ the $Q_{10}$ values of the winter and summer seasons were 1.49 and 1.45, respectively. The $R_{20}$($R_{stem}$ at $20^{\circ}C$ of stem temperature) was higher in summer ($1.23{\mu}mol\;m^{-2}s^{-1}$) than winter ($0.61{\mu}mol\;m^{-2}s^{-1}$). The woody tissue respiration in stems of red pine trees during the summer season amounted about 50% of the total respiration rates.

• Applied Chemistry for Engineering
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• v.9 no.7
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• pp.950-955
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• 1998

The objective of this study was to investigate the effect of running time, operating pressure, feed concentration and circulation rate on the permeation flux and the rejection rate in cross-flow ultrafiltration of polyethylene glycol(PEG) solution of molecular weight($M_w$) 8000 and 20000. The membranes used for this study were MWCO(Molecular Weight Cut-off) of 6 K and 20 K. The experiments were performed at the operating pressures of 7, 14 and 28 psi, the circulation rates of 1000 mL/min and 2000 mL/min, and the feed concentration of 100 mg/L and 1000 mg/L. At a constant pressure, the permeation flux and the observed rejection($R_o$) appeared to be approximately constant within the range of running time, 0~480 min. The permeation flux increased with increasing the operating pressure, and it increased with decreasing the feed concentration and decreasing Mw of PEG at a given pressure. On the other hand, $R_o$ decreased slightly with increasing the operating pressure. However, $R_o$ increased with increasing the feed concentration and increasing of $M_w$ of PEG at a given pressure. The variation in circulation rates did not cause any significant influence on the permeation flux. Increasing of circulation rate caused the increase of $R_o$, and $\alpha$ was increased substantially with the decrease of $M_w$ of PEG. The dimensionless parameter. permeability ratio($\alpha$), which was used to investigate flux-pressure behavior, was increased with the increase in circulation rate and operating presure. The value of $\alpha$ was less than 1 in all cases. The estimated intrinsic rejection(R). which was obtained from mass transfer coefficient, was decreased with the increase of operating pressure. However R increased with the increase of linear velocity of feed and $M_w$ of PEG.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.1
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• pp.13-23
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• 2008

The aim of the present study was designed to establish comparatively the inhibitory effects of $D_1$-like and $D_2$-like dopaminergic receptor agonists, SKF81297 and R(-)-TNPA on the release of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from the isolated perfused model of the rat adrenal medulla. SKF81297 $(30{\mu}M)$ and R-(-)-TNPA $(30{\mu}M)$ perfused into an adrenal vein for 60 min, produced great inhibition in the CA secretory responses evoked by ACh $(5.32{\times}10^{-3}\;M)$, DMPP $(10^{-4}\;M)$, McN-A-343 $(10^{-4}\;M)$, high $K^+$ $(5.6{\times}10^{-2}\;M)$, Bay-K-8644 $(10{\mu}M)$, and cyclopiazonic acid $(10{\mu}M)$, respectively. For the release of CA evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid, the following rank order of inhibitory potency was obtained: SKF81297>R-(-)-TNPA. However, R(+)-SCH23390, a selectve $D_1$-like dopaminergic receptor antagonist, and S(-)-raclopride, a selectve $D_2$-like dopaminergic receptor antagonist, enhanced the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid only for $0{\sim}4$ min. The rank order for the enhancement of CA release evoked by high $K^+$, McN-A-343 and cyclopiazonic acid was R(+)-SCH23390>S(-)-raclopride. Also, the rank order for ACh, DMPP and Bay-K-8644 was S(-)-raclopride > R(+)-SCH23390. Taken together, these results demonstrate that both SKF81297 and R-(-)-TNPA inhibit the CA release evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors and the membrane depolarization from the isolated perfused rat adrenal gland without affecting the basal release, respectively, but both R(+)-SCH23390 and S(-)-raclopride facilitate the CA release evoked by them. It seems likely that the inhibitory effects of SKF81297 and R-(-)-TNPA are mediated by the activation of $D_1$-like and $D_2$-like dopaminergic receptors located on the rat adrenomedullary chromaffin cells, respectively, whereas the facilitatory effects of R(+)-SCH23390 and S(-)-raclopride are mediated by the blockade of $D_1$-like and $D_2$-like dopaminergic receptors, respectively: this action is possibly associated with extra- and intracellular calcium mobilization. Based on these results, it is thought that the presence of dopaminergic $D_1$ receptors may play an important role in regulation of the rat adrenomedullary CA secretion, in addition to well-known dopaminergic $D_2$ receptors.