• Bulletin of the Korean Chemical Society
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• v.35 no.9
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• pp.2774-2780
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• 2014

A dynamics study of relaxation and fragmentation of icosahedral argon cluster with a vibrationally excited $Ar_2^+$ (${\nu}$) is presented. Local translation is shown to be responsible for inducing energy flow from the embedded ion to host atoms and fragmentation of the cluster consisting of various low frequency modes. The total potential energy of $(Ar_2^+)Ar_{12}$ is formulated using a building-up procedure of host-guest and host-host interactions. The time dependence of ion-to-host energy transfer is found to be tri-exponential, with the short-time process of ~100 ps contributing most to the overall relaxation process. Relaxation timescales are weakly dependent on both temperature (50-300 K) and initial vibrational excitation (${\nu}$ = 1-4). Nearly 27% of host atoms in the cluster with $Ar_2^+$ (${\nu}$ = 1) fragment immediately after energy flow, the extent increasing to ~43% for ${\nu}$ = 4. The distribution of fragmentation products of $(Ar_2^+)Ar_{12}{\rightarrow}(Ar_2^+)Ar_n+(12-n)Ar$ are peaked around $(Ar_2^+)Ar_8$. The distribution of dissociation times reveals fragmentation from one hemisphere dominates that from the other. This effect is attributed to the initial fragmentation causing a sequential perturbation of adjacent atoms on the same icosahedral five-atom layer.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.5
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• pp.543-548
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• 2014

In this paper, the dielectric relaxation and reliability of high capacitance density metal-insulator-metal (MIM) capacitors using $Al_2O_3-HfO_2-Al_2O_3$ and $SiO_2-HfO_2-SiO_2$ sandwiched structure under constant voltage stress (CVS) are characterized. These results indicate that although the multilayer MIM capacitor provides high capacitance density and low dissipation factor at room temperature, it induces greater dielectric relaxation level (in ppm). It is also shown that dielectric relaxation increases and leakage current decreases as functions of stress time under CVS, because of the charge trapping effect in the high-k dielectric.

• Journal of Veterinary Clinics
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• v.16 no.1
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• pp.65-68
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• 1999

This study was carried to get detailed information about the analeptic effect of yohimbine on succinylcholine muscle relaxant. Succinylcholine was administered intra- venously at a dose rate of 0.05 mg per kg of body weight and then ten minutes after the succinylcholine injection, yohimbine was administered intravenously at a dose rate of 0.1 mg per kg of body weight. The results obtained were as follows. 1. Induction time of muscle relaxation was fast and favourable as 38 seconds. 2. Mean arousal time and mean walk time were significantly shortened by yohimbine administration in the dogs immobilized with succinylcholine (p＜0.01). 3. Heart rate was slightly increased after succinylcholine administration, and increased significantly after yohimbine administration compared to the control group (p＜0.05). 4. Glucose concentration was slightly increased after succinylcholine administration, and decreased after yohimbine administration compared to the control group.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.12
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• pp.1494-1500
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• 2004

A zero-dimensional direct simulation Monte Carlo(DSMC) model is developed for simulating diatomic gas including vibrational kinetics. The method is applied to the simulation of two systems: vibrational relaxation of a simple harmonic oscillator and translational-rotational-vibrational energy exchange process under heating and cooling. In the present DSMC method, the variable hard sphere molecular model and no time counter technique are used to simulate the molecular collision kinetics. For simulation of diatomic gas flows, the Borgnakke-Larsen phenomenological model is adopted to redistribute the translational and internal energies.

• Korean Journal of Materials Research
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• v.17 no.1
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• pp.25-30
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• 2007

The in-situ scanning electron microscopy observation of real-time hillock evolution in pure hi thin films on glass substrate during Isothermal annealing was analyzed quantitatively to understand the compressive stress relaxation mechanism by focusing on the effect of Mo interlayer between Al film and glass substrate. There is a good correlation between the hillock-induced stress relaxation by in-situ scanning electron microscopy observation ana the measured stress relaxation by wafer curvature method. It is also clearly shown that the existence of Mo interlayer plays an important role in hillock formation probably due to the large difference in interfacial diffusivity of Al films.

• Polymer(Korea)
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• v.26 no.6
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• pp.728-736
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• 2002

The thermal and dielectric properties of unsaturated polyester resin system during cure were analyzed under Isothermal conditions. Both $varepsilon$′ and $varepsilon$" decreased and dipole relaxation was observed under isothermal conditions during cure. The ionic conductivity decreased linearly with the conversion according to the Kienle-Rate equation (ln($varepsilon$"$_{ionic}$we$_{0}$)=C$_{r}$$alpha$+C$_{0}$) up to $alpha$=0.15, after which it aparted from the relationship due to the entanglement of polymer chains. The effect of ionic conductivity was revealed to be larger than that of dipole motion during the whole cure through the electrical modulus analysis. Although dielectric motion was analyzed with Debye model, it was observed only at a narrow time region of middle stage of cure. In order to estimate the dielectric properties during the whole cure, the Havriliak-Negami model was considered and modified with the strong effect of ionic conductivity. The changes of $varepsilon$′ and $varepsilon$" were well estimated with this modified Havriliak-Negami model.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.37 no.4
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• pp.15-24
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• 2000

The dielectric relaxation of high-dielectric capacitors could be understood as a dynamic property of the capacitor in the time domain, which is regarded as a primarily important charge loss mechanism during the refresh time of DRAMs. Therefore, the equivalent circuit of the dielectric relaxation of the high-dielectric capacitor is essentially required to investigate its effects on DRAM. Nevertheless, There is not any theoretical method which is generally applied to realize the equivalent circuit of the dielectric relaxation. Recently, we have developed a novel procedure for the circuit modeling of the dielectric relaxation of high-dielectric capacitor utilizing the frequency domain. This procedure is a general method based on theoretical approach. We have also verified the feasibility of this procedure through experimental process. Finally, we successfully investigated the effect of dielectric relaxation on DRAM operation with the obtained equivalent circuit through this new method.

• Korean Journal of Veterinary Research
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• v.34 no.3
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• pp.479-486
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• 1994

Effects of catecholamines and the site of receptor of catecholamines were investigated in the longitudinal muscle of the rumen. In order to this experiment, specimens were obtained from 35 Korean Native Cattles, 2-3 years old, in the Kwang-ju area slaughterhouse. Longitudinal muscle strips of rumen were made from sample, and then measured the isometric contraction with physiograph in $37{^{\circ}C}$ organ bath. The results were summarized as follows. 1. 30% of all strips showed rhythmic contraction after short incubation time. 2. Relaxation produced by catecholamines in this preparations increased in a dose-dependant manner. 3. Isoproterenol(${\beta}$-agonist) caused relaxation, but phenylephrine(${\alpha}_1$-agonist) and xylazine(${\alpha}_2$-agonist) were unaffected. 4. The relaxation induced by epinephrine and norepinephrine were not affected by phentolamine(${\alpha}$-blocker) and prazosin(${\alpha}_1$-blocker), yohimbine(${\alpha}_2$-blocker). But propranolol(${\beta}$-antagonist) abolished the effect of catecholamines on relaxation. 5. It is concluded that catecholamines produced relaxation in the longitudinal muscle of rumen via the ${\beta}$-adrenoceptor.

• Journal of the Korean Society of Visualization
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• v.18 no.3
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• pp.42-51
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• 2020

This study performs a numerical simulation of lid driven rectangular cavity flow with different aspect ratios of k = 0.5 to 4 under Reynolds 100, 1,000, 10,000 by using multi-relaxation time (MRT) Lattice Boltzmann Method (LBM). In order to achieve better convergence, well-posed boundary conditions in the domain should be defined such as no-slip condition on side and bottom solid wall surfaces and uniform horizontal velocity on the top of the cavity. This study focuses on the flow inside different shape of rectangular cavity with the aim to observe the effect of the Reynolds number and aspect ratio on the flow characteristics and primary/secondary vortex formation. In order to validate the study, the results have been compared with existing works. The result shows that the Reynolds number and the aspect ratio both has substantial effects on the flow inside the lid-driven rectangular cavity.

• Journal of Korean Academy of Nursing
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• v.15 no.1
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• pp.76-96
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• 1985

Postoperative pain is one of the most frequently occurred pain in hospitals, but it has been underestimated because it is only a part of postoperative physiological Process and may disappear in time. It is necessary that nurses me the relaxation technique, planning and implementing by themselves independently, to reduce this postoperative pain. This study is aimed at showing the effect of relaxation technique on reduction of postoperative pain, and exploring the factors influencing postoperative. pain Fifty-seven patients with abdominal surgery who admitted in attacked D Medical Center to K University in Daegu have been studied. Of them twenty-nine were experimental group and the remaining twenty-eight were control group. This study has been conducted for collecting data through interviews and observation from August 23 to October 24, 1984. The tools of this study were two kinds: Postoperative Pain Scale is obtained from a review of references by the researcher, and relaxation technique, designed to use postoperative setting adequately, is also obtained from a review of references by the researcher. After confiriming no significant differences between the two groups, the hypotheses were statistically verified by x²-test, t-test, and pearson Correlation Coefficient. The results of this study are summerized as follows; ＊ The nam hypothesis that the experimental group who use relaxation technique will have less degree of postoperative pain than the control group who don't use relaxation technique is devided into three sub-hypotheses. 1. The first sub-hypothesis that the experimental group will have less score of postoperative pain than control group was accepted (t=7.810, p <.01). Even with controlling pain threshold, showing difference in some degree between the two groups, the experimental group has less score of postoperative pain than the control group. Therefore this confirms the acceptance of the first sub-hypothesis more strongly. 2. The second sub-hypothesis that the expermental group will have less frequency of analgesics than the control group is accepted (x²=9.85, p <.01). 3. The third sub-hypothesis that the experimental group will have less variation of pulse, respiration, and blood pressure between pre End post operative periods than the control group is rejected. So this hypothesis is reverified through comparing the variation of pulse, respiration, and blood pressure between pre and post changing Position to measure the pure effect of relaxation technique. pulse and respiration is significantly lowered in the experimental group (t=7.209, p<.01, t=3.473, p<.01), but systolic and diastolic blood pressure is not different significantly between the two groups (t= 1.309, p＞.05, t=1. 727 p>.05). Therefore the third sub-hypothesis is partially accepted. Conclusively, the researcher thinks that it is necessary that nurses should provide patients with relaxation technique to reduce postoperative pain, and to increase independence of nursing.