• The Korean Journal of Physiology
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• v.22 no.2
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• pp.207-218
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• 1988

Effects of 1, 4-dihydropyridine compounds, such as nifedipine, nisoldipine, nitrendipine, and nimodipine which were calcium antagonists on the normal and Ca-dependent, slow channel mediated action potentials in the guinea pig's papillary muscle were investigated. The glass microelectrode was impaled into a papillary muscle cell for measurements of potential changes with the simultaneous tracing of isometric contraction. The concentration of Ca antagonists were 1 mg/l (nifedipine and nisoldipine), 2 mg/l (nitrendipine and nimodipine), which showed the maximal inhibition of isometric contraction (above 90%) and simultaneous effects on the normal action potentials and only the halves of those concentrations were sufficient to observe the effects on the calcium action potentials. The data for analysis were only chosen when the microelectrode was maintained in a cell throughout the experiments. 1, 4-Dihydropyridine compounds decreased the action potential duration but did not affect the resting membrane potential, overshoot, and upstroke velocity of the normal action potentials with the decrease in the isometric contraction. And with the decrease in the area and amplitude of isometric contraction, the area, amplitude, upstroke velocity and duration of Ca action potential was decreased. But the differences in the effects of the Ca antagonists were not observed. Therefore it is inferred that the changes in normal and Ca action potential induced by the 1, 4-dihydropyridine compounds with a common chemical structure would be caused by the slow inward Ca-current, not by a fast Na-current.

• YAKHAK HOEJI
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• v.32 no.4
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• pp.258-273
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• 1988

In this study attempts were made to observe the effects of guanabenz on renal function in dog, which manifests the antihypertensive action by inhibition of sympathetic tone through stimulating the presynaptic adrenoceptor (${\alpha}_2-adrenoceptor$). Guanabenz, when injected at a dose of $30.0{\mu}g/kg$, or infused at a dose of $3.0{\mu}g/kg/min$ intravenously, produced diuretic action with increased amounts of $Na^+\;and\;K^+$ in urine, and with decreased reabsorption rates of $Na^+\;and\;K^+$ in renal tubules. It was also observed that the rates of osmolar and free water clearances were increased, but the glomerular filtration rate and renal plasma flow were not changed. Guanabenz injected at a dose of $3.0{\mu}g/kg$ into a carotid artery or infused intravenously at a dose of $3.0{\mu}g/kg/min$ in a state of water diuresis elicited the diuretic action of the similar aspect as a case of guanabenz given intravenously. The diuretic action produced by guanabenz was completly blocked by pretreatment of i.v. prazosin, ${\alpha}_1-adrenoblocking$ agent, or of i.v. yohimbine, ${\alpha}_2-adrenergic$ blocking agent. Prazosin, when given into a renal artery, inhibited the diuretic action by i.v. guanabenz in only injected kidney, whereas in case of yohimbine the action was inhibited in both kidney. Guanabenz infused at a dose of $1.0{\mu}g/kg/min$ into a renal artery exhibited no significant changes of renal function in both kidney. In denervation experiments, guanabenz given intravenously produced typical diuretic action in innervated kidney, whereas in denervated kidney, it did not affect the action at initial period but exhibited the action with increase of only free water clearance at later period. These results suggest that guanabenz produced diuretic action in dog by inhibition of electrolyte reabsorption rates in renal tabules, mainly proximal tubule and of ADH release, which is mediated by stimulating of central sympathetic ${\alpha}_2-receptor$.

• Journal of Broadcast Engineering
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• v.25 no.3
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• pp.374-385
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• 2020

In this paper, we propose a preprocessing technique to solve the problems of action recognition with Equirectangular Projection (ERP) video. The preprocessing technique proposed in this paper assumes the person object as the subject of action, that is, the Object of Interest (OOI), and the surrounding area of the OOI as the ROI. The preprocessing technique consists of three modules. I) Recognize person object in the image with object recognition model. II) Create a saliency map from the input image. III) Select subject of action using recognized person object and saliency map. The subject boundary box of the selected action is input to the action recognition model in order to improve the action recognition performance. When comparing the performance of the proposed preprocessing method to the action recognition model and the performance of the original ERP image input method, the performance is improved up to 99.6%, and the action is obtained when only the OOI is detected. It can also see the effects of related video summaries.

• Computers and Concrete
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• v.1 no.3
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• pp.325-354
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• 2004

Slabs in buildings and bridge decks, which are restrained against lateral displacements at the edges, have ultimate strengths far in excess of those predicted by analytical methods based on yield line theory. The increase in strength has been attributed to membrane action, which is due to the in-plane forces developed at the supports. The benefits of compressive membrane action are usually not taken into account in currently available design methods developed based on plastic flow theories assuming concrete to be a rigid-plastic material. By extending the existing knowledge of compressive membrane action, it is possible to design slabs in building and bridge structures economically with less than normal reinforcement. Recent research on building and bridge structures reflects the importance of membrane action in design. This paper describes the finite element modelling of membrane action in reinforced concrete slabs through optimisation of a simple concrete model. Through a series of parametric studies using the simple concrete model in the finite element simulation of eight fully clamped concrete slabs with significant membrane action, a set of fixed numerical model parameter values is identified and computational conditions established, which would guarantee reliable strength prediction of arbitrary slabs. The reliability of the identified values to simulate membrane action (for prediction purposes) is further verified by the direct simulation of 42 other slabs, which gave an average value of 0.9698 for the ratio of experimental to predicted strengths and a standard deviation of 0.117. A 'deflection factor' is also established for the slabs, relating the predicted peak deflection to experimental values, which, (for the same level of fixity at the supports), can be used for accurate displacement determination. The proposed optimised concrete model and finite element procedure can be used as a tool to simulate membrane action in slabs in building and bridge structures having variable support and loading conditions including fire. Other practical applications of the developed finite element procedure and design process are also discussed.

• Journal of Distribution Science
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• v.16 no.8
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• pp.69-77
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• 2018

Purpose - With growing competition in the service distribution industry, the importance of managing customer complaints has increased. If firms handle customer complaints effectively, they can strengthen customer loyalty and repurchase intention. Many studies have focused on customers expressing complaints, yet research on silent customers is scant. This study focuses on two types of complainers and non-complainers. In other words, this study is to examine the value of voice complaint intention and no-action intention. This study also investigates how perceptual and relational factors affect complaint intention. Research design, data, and methodology - This study was carried out using the survey with undergraduate students who have faced a service failure in a retail store(fast foods, electronics, apparel). And if such complaint were to occur again, respondents were asked about any possible action they would take. 300 questionnaires were distributed and a total of 279 respondents provided complete and usable data. The sample consisted of 158 males(56.6%) and 121 females(43.4%). The structural equation modeling analysis was used for the hypothesis test. Results - The results are as follows. First, attitude toward complaining, likelihood of successful complaint, and ease of complaint were positively related to voice complaint intention. Second, attitude toward complaining, likelihood of successful complaint, and ease of complaint were negatively related to no-action intention. Third, commitment was positively related to voice complaint intention but didn't have a significant negative impact on no action. Forth, voice complaint behavior reduced switching intention and no-action intention enhanced switching intention. Conclusions - The findings of this study confirm the value of complaint behavior and show voice complaint intention and no-action intention should be managed differently. Voice complaint intention is evaluated positively because it reflects customers' concerns about the company, while no-action intention is evaluated negatively. Attitude toward complaing is the most effective in increasing voice complaint intention and likelihood of successful complaint is a major factor in reducing no-action intention. Also, in explaining switching intention, voice complaint intention plays a more important role than no-action intention.

• Journal of Pharmaceutical Investigation
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• v.8 no.1
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• pp.6-16
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• 1978

We obtained 4 kinds of extract fraction from Acanthopanacis Radicis Cortex and studied on the influence to the blood pressure of rabbit. These 4 fractions were obtained as follows; Fraction I was insoluble fraction by 99% ethanol from 80% methanol extract of Acanthopanacis Radicis Cortex, fraction II, precipitated fraction by ether from 99% ethanol soluble fraction of 80% methanol extract of Acanthopanaacis Radicis Cortex, fraction III, no precipitated fraction by ether from 99% ethanol soluble fraction of above 80% methanol extract and fraction IV, water extract of Acanthopanacis Radicis Cortex. All of fractions, when administered into ear-vein of rabbit, produced fall of blood pressure. Among these 4 fractions, although fraction III was not only the most potent but had the greatest efficacy, we observed the mechanism of hypotensive action of Acanthopanacis Radicis Cortex, making use of fraction II which was thought as a comparatively pure fraction. Hypotensive action of fraction II (APF II) was not affected by vagotominization but markedly inhibited by atropine. Pretreatment of bethanidine showed a tendency to weaken the depressor action of APF II, although it was not a significant result, but diphenhydramine did not influence APF II action. Phentolamine, guanethidine and chlorisondamine inhibited significantly the hypotensive action of APF II. APF II elicited the potentiation of norepinphrine pressor action dependent on the time-factor whereas it did not influence angiotesin pressor action. It is seemed that APF II exhibited hypotensive action, causing peripheral muscarinic-effect and centrally induced sympatholytic action.

• The Korean Journal of Pharmacology
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• v.22 no.2
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• pp.135-143
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• 1986

This study was designed to investigate the role of calcium in the function of an isolated perfused rabbit kidney and its effect on the diuretic action of furosemide. The administrations of hydralazine and verapamil produced remarkable diuretic actions mainly by decreasing renal resistance. The administration of furosemide in combination with hydralazine or verapamil produced remarkable diuretic action and there was no difference between the two groups. The administration of quinidine produced a diuretic action in spite of vasoconstriction and potentiated the diuretic action of furosemide. In the calcium-free perfusion medium, the administration of calcium produced a marked diuretic action in spite of vasoconstriction and potentiated significantly the diuretic action of furosemide. The administration of quinidine did not alter renal function and the diuretic action of furosemide, but the combined administration of quinidine and calcium showed antidiuretic effect due to excessive vasoconstriction in the calcium-free perfusion medium. Although the administration of verapamil produced a slight diuretic action in the calcium-free perfusion medium, verapamil did not alter the diuretic action of calcium as well as the diuretic actions of furosemide alone and in combination with calcium. The results of this experiment show that calcium, verapamil and quinidine produced diuretic actions and calcium potentiates the diuretic action of furosemide.

• Bulletin of the Korean Mathematical Society
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• v.26 no.1
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• pp.47-52
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• 1989

Methods of Riemannian geometry has played an important role in the study of compact transformation groups. Every effective action of a compact Lie group on a differential manifold leaves a Riemannian metric invariant and the study of such actions reduces to the one involving the group of isometries of a Riemannian metric on the manifold which is, a priori, a Lie group under the compact open topology. Once an action of a compact Lie group is given an invariant metric is easily constructed by the averaging method and the Lie group is naturally imbedded in the group of isometries as a Lie subgroup. But usually this invariant metric has more symmetries than those given by the original action. Therefore the first question one may ask is when one can find a Riemannian metric so that the given action coincides with the action of the full group of isometries. This seems to be a difficult question to answer which depends very much on the orbit structure and the group itself. In this paper we give a sufficient condition that a subgroup action of a compact Lie group has an invariant metric which is not invariant under the full action of the group and figure out some aspects of the action and the orbit structure regarding the invariant Riemannian metric. In fact, according to our results, this is possible if there is a larger transformation group, containing the oringnal action and either having larger orbit somewhere or having exactly the same orbit structure but with an orbit on which a Riemannian metric is ivariant under the orginal action of the group and not under that of the larger one. Recently R. Saerens and W. Zame showed that every compact Lie group can be realized as the full group of isometries of Riemannian metric. [SZ] This answers a question closely related to ours but the situation turns out to be quite different in the two problems.

• Korean Journal of Human Ecology
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• v.6 no.1
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• pp.111-127
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• 1997

This study was to examine home economics (HE) teachers' and the 1st-grade students' needs perception toward the purposes of HE education in middle school which has been practced since 1995 for both male and female students. This study, attempted (1) to analyze needs priority among the educational purposes of HE subject in relation to three systems of actions; (2) to compare differences between HE teachers' and students' perception concerning the degree of importance and achievement of the educational purposes of HE subject: and (3) to examine what they conceive as the problems In the current HE education. The survey was conducted with the samples of 600 1st-grade middle school students and 101 middle school HE teachers during the period of February-March 1996. The questionnaire used in this study was a modified version which had already been developed along with the 6th HE curriculum. For data analyses, SAS program was utilized to get Means and to perform both discrepancy test and t-test. The findings of this study were summarized as follows: first, with respect to each group's perception of the importance of the purposes related to three systems of action, HE teachers emphasized the importance of the purposes related to emancipatory action, while students placed more emphasis on the purposes related to technical action. Second, in terms of the degree of achievement, students had more positive perception on the degree of achievement of the purposes related to technical action than HE teachers did. Both groups marked low level of recognition on the degree of achievement of the purposes related to emancipatory action. Third, with respect to needs priority, HE teachers placed the first priority on emancipatory action, the second on technical action, and the last on communicative action: in the case of students, the first priority was on technical action, the second on communicative action, and the last on emancipatory action. In addition, the analysis of the opinions on the 6th curriculum revealed that most respondents found it necessary to secure adequate amount of classes for HE education. Also they shared the recongnition that HE curriculum should be renovated into the one which would fully appreciate the purposes of HE education from the perspective of the practical concerns of action which are distinct from the functional and technical concerns of passive learning. The findings of this study can serve as basic data for establishing the new purposes of HE education which put more emphasis on the purposes related to emancipatory action: as well as for developing an enhanced curriculum and reinforcing the identity of HE education.

• The Journal of the Korea Contents Association
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• v.15 no.11
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• pp.658-671
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• 2015

The present study explores the effect of blended action learning program on the improvement of the self-directed learning skills of university students. For this, students in the college of education at D University located in the capital area were selected to form 30 students of the experimental group and 30 of the control group. The average age of the subjects is 22.3. They are students in the $2^{nd}$ to $4^{th}$ year of university and the demographic background is relatively homogeneous. The experiment was conducted in the Sociology of Education class (a teacher training course). The self-directed learning skills were pre-tested at the beginning of the term. After that, the experimental group had the class with blended action learning program, and the control group had the class with action learning program. The post-test was carried out at the end of the term. For data analysis, ANCOVA was carried out to compare the scores on post-test of the two groups in consideration of the scores on the pre-test. The results show that first, for the improvement of self-directed learning skills of university students, blended action learning program is more effective than action learning program. Second, in the class for learners with lower degree of cognition and experience, blended action learning program was more effective than action learning program. Third, in terms of management of learning resources and utilization of learning strategies, both action learning program and blended action learning program were not effective. In summary, for improvement of the self-directed learning skills of university students, action learning program, which is a learning method focused on learner's participation and practice, is more effective than the traditional collective lecture among diverse teaching methods. Yet in consideration of the elementary level of university students in terms of intelligence and experience, active use of blended action learning program is required.