• Journal of Communications and Networks
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• v.10 no.2
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• pp.175-185
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• 2008

In this paper, we investigate the effect of cooperative and selection relaying schemes on multiuser diversity in downlink cellular systems with fixed relay stations (RSs). Each mobile station (MS) is either directly connected to a base station (BS) and/or connected to a relay station. We first derive closed-form solutions or upper-bound of the ergodic and outage capacities of four different downlink data relaying schemes: A direct scheme, a relay scheme, a selection scheme, and a cooperative scheme. The selection scheme selects the best access link between the BS and an MS. For all schemes, the capacity of the BS-RS link is assumed to be always larger than that of RS-MS link. Half-duplex channel use and repetition based relaying schemes are assumed for relaying operations. We also analyze the system capacity in a multiuser diversity environment in which a maximum signal-to-noise ratio (SNR) scheduler is used at a base station. The result shows that the selection scheme outperforms the other three schemes in terms of link ergodic capacity, link outage capacity, and system ergodic capacity. Furthermore, our results show that cooperative and selection diversity techniques limit the performance gain that could have been achieved by the multiuser diversity technique.

• Korean Journal of Childcare and Education
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• v.17 no.6
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• pp.29-52
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• 2021

Objective: The purpose of this study was to investigate the mediating effects of the parent-teacher trust relationship and cooperative behavior in the relationship between the emotional intelligence of infant teachers and their play teaching efficacy. Methods: A total number of 216 teachers in charge of infants under the age of two at childcare centers located in H, Y, and O cities in Gyeonggi-do participated in the survey. Using SPSS 23.0 and AMOS 22, descriptive statistics, correlation and structural equation model were analyzed. Results: First, the emotional intelligence of infant teachers had a direct effect on play teaching efficacy. Second, the emotional intelligence of infant teachers influenced play teaching efficacy through parent-teacher's trust relationship. Third, the emotional intelligence of infant teachers influenced play teaching efficacy through parent-teacher cooperative behavior. Fourthly, it was found that the parent-teacher trust relationship and cooperative behavior were mediated sequentially in the influence of the emotional intelligence of infant teachers on play teaching efficacy. Conclusion/Implications: The results of this study emphasize the importance of improving the emotional intelligence of teachers and the trust and cooperation between parents and teachers in order to increase the ability of early childhood teacher's play teaching efficacy.

• International Journal of Advanced Culture Technology
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• v.5 no.1
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• pp.1-8
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• 2017

The purpose of the present study is to examine the effect of civic cooperation with the police on the number of crime that the police must solve by conducting simulation based on system dynamics. The study sets police oriented-policing model and police-citizen cooperative model to investigate the effect of civic cooperation with the police. As a result of the simulation, the police oriented-policing model shows that the number of crime that police must solve is increasing over time, while the police-citizen cooperative model shows that the number of crime that must be solved by the police is keeping it stable in the increase of crimes. Comparing both models, civic cooperation with the police is more effective in reducing or deterring crime than police oriented-policing activity. The study proves that building cooperative relationship between citizens and the police can become a strategic method for controlling crime effectively without a rapid increase in police finance. It is meaningful in terms of presenting a dynamic change of interaction for reducing crimes between civic cooperation with the police and policing activity of the police over time.

• Archives of Pharmacal Research
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• v.9 no.2
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• pp.75-79
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• 1986

The effect of phenothiazine derivatives on the thermotropic transition of liposomal lipid bilayer made of dipalmitoyl phosphatidylchline and dipalmitoyl phosphatidic acid was investigated with differential scanning calorimetry. The thermograms of the liposomal bilayer incorporated with levomepromazine, chlopromazine, prochloperazine, perphenazine and fluphenazine were obtained and the size of cooperative unit of the transition were calculated from the ratio of the van't Hoff enthalpy change to the calculated enthalpy change of the transition. The results showed that incorporation of phenothiazine derivatives into the liposomal bilayer reduced the transition temperature at which the transition from solid state to liquid-crystalline state occurs, and broadened the thermogram peaks. Phenothiazine derivatives also significantly reduced the size of cooperative unit of the transition. The effect of the drugs was proportional to the concentration of the drug in the bilayer. This means that phenothiazine derivatives might have significant fluidizing effects on the biomembrane. The sizes of cooperative unit were successfully corrlated with phar-macological activities of the drugs and the surface pressure increases of lipid monolayer by these drugs. These correlations might be ascribed to a possible hydrophobic nature of interaction between the biomembrane and the drugs involved in their pharmacology.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.181-184
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• 1988

The effect of clover saponin on the phase transition of liposomal lipid bilayers of dimyristoyl phosphatidylcholine was investigated with differential scanning calorimetry. The thermograms of the liposomal bilayers incorporated with the clover saponin were obtained, and the enthalpy changes and the sizes of cooperative unit of the transition were calculated. The results showed that incorporation of the clover saponin into the liposomal bilayers effectively reduced the transition temperature at which the transition from solid state to liquid-crystalline state occurs, and broadened the thermogram peaks. It also reduced the size of cooperative unit of the transition. These results indicate that the clover saponin might have significant effect on the fluidity of biological membranes.

• Journal of Digital Convergence
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• v.14 no.8
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• pp.137-150
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• 2016

Labor-management relations are essential to corporation to secure competitiveness and a continuous development. However it is difficult to establish labor-management relations. This study focuses on the effect of cooperative industrial relations in trust and commitment of organization and labor union through 300people of 12 companies who belong to the Korean Confederation of Trade Unions. As a result of the study, cooperative industrial relations have a positive effect on the trust in organization and labor-management. Furthermore, the trusts of both organization and labor-management relations have a positive effect toward its commitment. This research result is an important factor to change a strategy of the labor union which cannot break out original roles. The cooperative industrial relations are also necessary for organization.

• Journal of the Korean School Mathematics Society
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• v.17 no.4
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• pp.465-492
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• 2014

In this study, through the analysis of the mathematics curriculum and textbooks, we produce the cooperative learning activity sheets which was appropriate instructional content for various levels. And, by using them appropriately at the levels of student learning on their own interest, we enhance academic achievement and cooperative learning attitudes. Specific for details for this study are as follows: First, through the applying a variety of the differentiated cooperative learning activity sheets and developing instruction learning, we improve the academic achievement. Second, through the making and utilizing the differentiated cooperative learning activity sheets and the interest and attitudes in mathematics, we improve the cooperative learning attitude. Third, through the levels of the subgroup cooperative learning, we improve the math learning abilities through a learner-centered. Further the purpose of this study is to bring up complementary cooperative spirit among colleagues.

• Journal of Korean Home Economics Education Association
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• v.12 no.1
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• pp.47-58
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• 2000

The purpose of this study is to investigate the effects of cooperative learning method on student achievement and attitude in Home Economics. and that what sort of effectiveness be existed between the two groups. Homogeneous & Heterogeneous one in achievement. A junior middle school in Kwangju was served for the study. Setting two groups: One is for cooperative learning and other for traditional learning. Two classes were provided with cooperative learning method. while one class with traditional learning method. Two hours of a week were devoted for the experiment. and it was also planned to be lasted six weeks from the third of June. 1998. until the 13th of July. 1998. The results are as follows: 1) Student achievement from cooperative learning method showed a little higher than those from traditional learning method. 2) Cooperative learning method was more effective than traditional learning method. mental attitude toward school. lessons and teachers were more higher than those the traditional learning method. 3) The group of Heterogeneous members was higher than the group of Homogeneous members in their student achievement. 4) It is noticeable that two groups under cooperative learning method. however showed some difference when each of them is placed in different organization. The group of Heterogeneous members was more affirmative attitude toward school. lessons and teachers than the one Homogeneous members.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.14 no.10
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• pp.4231-4245
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• 2020

Non-orthogonal multiple access (NOMA) is widely studied in both academia and industry due to its high spectral efficiency over orthogonal multiple access (OMA). To effectively improve spectrum efficiency, an amplify-and-forward (AF) cooperative NOMA system is proposed as well as a novel detection scheme is proposed, in which we first perform successive interference cancellation (SIC) twice at U1 for the two signals received from two time slots to remove interference from symbol 2, then two new signals apply max ratio combining (MRC). In addition, a closed-form upper bound approximation for the ergodic capacity of our proposed system is derived. Monte-Carlo simulations and numerical analysis illustrate that our proposed system has better ergodic capacity performance than the conventional cooperative NOMA system with decode-forward (DF) relay, the conventional cooperative NOMA system with AF relay and the proposed AF cooperative NOMA system in [16]. In addition, we can see that ergodic capacity of all NOMA cooperative systems increase with the increase of transmit SNR. Finally, simulations display that power allocation coefficients have little effect on ergodic capacity of all NOMA cooperative systems. This is due to this fact that ergodic capacity of two symbols can be complementary with changing of power allocation coefficients.

• Journal of Information Processing Systems
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• v.12 no.2
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• pp.295-309
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• 2016

Spectrum sensing is an essential function that enables cognitive radio technology to explore spectral holes and resourcefully access them without any harmful interference to the licenses user. Spectrum sensing done by a single node is highly affected by fading and shadowing. Thus, to overcome this, cooperative spectrum sensing was introduced. Currently, the advancements in multiple antennas have given a new dimension to cognitive radio research. In this paper, we propose a multiple energy detector for cooperative spectrum sensing schemes based on the evidence theory. Also, we propose a reporting mechanism for multiple energy detectors. With our proposed system, we show that a multiple energy detector using a cooperative spectrum sensing scheme based on evidence theory increases the reliability of the system, which ultimately increases the spectrum sensing and reduces the reporting time. Also in simulation results, we show the probability of error for the proposed system. Our simulation results show that our proposed system outperforms the conventional energy detector system.