• 전기의세계
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• v.21 no.2
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• pp.20-24
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• 1972

The transient stability of the synchronous motor is generally improved by damper winding or flywheel. However the synchronous motor at full load will be pulled out from normal operation state when the period of power failure exceeds approximately ten cycle per second. This paper studies the method of improving the stability of synchronous motor by equipping the phase slipping switch between the motor and power source. This paper shows the motor does not pull out, which results from the decrease of power angle to about 30 electrical degrees by means of the switch even when the relatively long period of power failure brings the power angle to some 150 electrical degrees.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.179-180
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• 2017

In order to improve the constructability of tall building construction, there is increasing needs to derive the design output by performing construction engineering at the design phase. It contributes to minimizing wastes such as design changes and reworks as well as improving project performance. Therefore, in this study, we analyzed the application period and participants for engineering tasks derived from a previous study, and then regrouped to efficiently reflect them at the design phase. Considering similarity of application period and attributes, the existing 22 engineering tasks, which were classified into 5 factors, were reclassified into 13 groups. The results of this study can be used as basic data for efficient construction engineering execution at the design phase.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.65 no.12
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• pp.2159-2166
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• 2016

In the IEEE 802.11 DCF (Distributed Coordination Function) protocol, the binary exponential backoff algorithm is used to avoid data collisions. However, as the number of stations increases of, the collision probability tends to grow and the overall network performance is reduced. To solve this problem, this paper proposes a data transmission scheme based on the channel reservation method. In the proposed scheme, channel time is divided into reservation period and contention period. During the reservation period, stations succeeded in channel reservation transmit their own data packets in sequence without contention. During the contention period, each station sends its data packets through contentions as in DCF. During both the reservation period and the contention period, each station sends a request for channel reservation for the next reservation period to an AP (Access Point). After receiving such a channel reservation request from each station, the AP decides whether the reservation is succeeded and sends the result via a beacon frame to each station. Performance of the proposed scheme is analyzed through simulations. The simulation results show that the proposed scheme tends to reduce the collision probability of DCF and to improve the overall network performance.

• The Journal of Korean Obstetrics and Gynecology
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• v.21 no.1
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• pp.267-275
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• 2008

Purpose: The purpose of this study is to report the effect of oriental treatments for parkinsonism after puerperal period. Methods: We treated one 29-years-old female who had parkinsonism (dysarthria, gait disturbance, dizziness, tremor, rigidity, blurring of vision) after puerperal period with herb medication ( Chengsimondamtang -淸心溫膽湯, etc). Results: After oriental medical treatment, the clinical symptom of parkinsonism after puerperal period was improved. Conclusion: This case study shows that the oriental medical therapy is effective in treating parkinsonism after puerperal period. So that, it is helpful in decreasing the symptoms of patients and in improving quality of life.

• Child Health Nursing Research
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• v.22 no.3
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• pp.172-181
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• 2016

Purpose: This study was conducted to examine the effect of education on infection control for multidrug resistant organism (MDRO). Methods: One group pre-post time series design was used. Infection control education for MDRO infection was provided to nurses working in the Neonatal Intensive Care Unit (NICU). Knowledge and recognition were evaluated before and after education. Hand hygiene compliance, MDRO isolation rate and central line-associated bloodstream infection (CLABSI) rate were used as outcome variables. Data from 45 nurses was used for analysis. Results: General knowledge about MDRO increased (p=.011). Responses to questions about image of MDRO and MDRO management tended to change in a positive direction (p=.046). Hand hygiene compliance was 100% at pre-test, 79.5% during education period and 98.4% at post-education period. MDRO isolation rate was 6.83 per 1,000 patient days at pre-test, 10.24 during education period and 6.68 at post-education period. CLABSI rate was 3.76 per 1,000 central line days at pre-test, 6.84 during education period and 4.71 at post-education period. Conclusion: Findings indicate that the education program is effective in improving knowledge about MDRO in NICU nurses. However, more reliable indicators should be used to determine long-term effects.

• Journal of Korean Academy of Nursing
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• v.33 no.6
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• pp.686-692
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• 2003

Purpose: To assess the effect of handwashing improving program and MRSA carrier detection program on MRSA(methicillin resistant Staphylococcus aureus) infection rate in a intensive care unit. Method: The intervention was Nosocomial Infection(NI) control program consisted of hand washing improving program and identification and treatment of MRSA carrier. Data on the NI and MRSA infections were collected by an infection control nurse based on the definition of CDC. MRSA infection rates were calculated by the number of MRSA infection per 100 admissions or 1,000 patients-days. The difference of MRSA infection rates between pre and post intervention was tested by Chi-square at =.05. Result: MRSA infection rates 3.0% or 3.2 per 1,000 patient-days at the pre, 4.6% or 3.7 per 1,000 patient-days at the post, and the differences were not statistically significant (p=.411, p=.769 respectively). Conclusion: The handwashing improving program and MRSA carrier detection program was not effective in reducing the Nosocomial Infection(NI) or MRSA infection rates. It is recommended further studies with a longer intervention and follow-up period.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.2
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• pp.59-66
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• 2018

The purpose of this study is to investigate the method on improving the frequency of use and satisfaction rate of the community facilities and to evaluate relation between improving the frequency of use and satisfaction rate of the community facilities and improving the sense of community in apartments. The research subjects of this study is the four public lease apartments which is built around same period with same design guide. The survey method is a questionnaire survey, a experimental study, focus group interview, an analysing drawing. The result of study is as follows. The first, the frequency of use and satisfaction rate have been effected by the operation management system as well as the physical circumstance. The second, The frequency of use and satisfaction rate of the community facilities have had positive correlation with sense of community. The third, multimedia room and conference room with low usability need to change a multipurpose space such as cafe, classroom for learning on artistic topic with high demand from occupant. Finally, a mindset shift is required for architects to inspire community facilities as an important mediated space improving the sense of community by suggesting spaces for leisure and hobby activities.

• Journal of KIISE:Computing Practices and Letters
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• v.16 no.11
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• pp.1066-1070
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• 2010

In wireless network, energy efficiency is an important design consideration for continuous multimedia streaming service. This paper proposes a new streaming system, called BACASS (Buffer-Aware and Content-Aware Streaming System) that working on the 802.11e U-APSD (Unscheduled Automatic Power Save). The BACASS leads the DP (Doze Period) of U-APSD for improving energy efficiency by utilizing the PSNR based on content-aware and client buffer occupancy that is hinged on a network-aware streaming system using SVC. The simulation results demonstrate the effectiveness of the proposed streaming system.

• Journal of Korean Biological Nursing Science
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• v.12 no.3
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• pp.157-165
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• 2010

Purpose: The purpose of this study was to examine the effects of recreation combined exercise program on body composition, physical fitness and depression in elderly women in rural district over a three-month follow-up period. Methods: Recreation combined exercise program (RCEP) was composed of resistance exercise, walking and recreation activity twice a week. The subjects were 52 divided in to experimental group (n=28) and control group (n=24). Arm curl, chair stand, 2 min step test, back scratch, chair sit and reach were measured as pre- or post-test data. Also, Depression was expressed using geriatric depression scale as pre- or post-test data. $X^2$ test, paired t-test and t-test were performed using SAS program. Results: Arm curl (p=.023), 2 minute step test (p<.001), back scratch (p=.004) and chair sit and reach (p=.024) showed the significant difference in the comparison between groups. Depression showed the significant difference in the comparison between groups (p=.008). Conclusion: These findings indicated the RCEP has positive influence upon increasing the physical fitness and improving the depression level. In conclusion, the regular RCEP will contribute to the improving physical and psychologic aspect in elderly women over the long period.

• ETRI Journal
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• v.38 no.5
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• pp.885-895
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• 2016

The lowest power mode (passive-standby mode) was proposed for reducing the power consumption of set-top boxes in a standby state when not receiving content. However, low-power set-top boxes equipped with the lowest power mode have been rarely commercialized because of their low-quality user experience. In the lowest power mode, they deactivates almost all of operational modules and processes, and thus require dozens of seconds for activation latency (that is, the latency for activating all modules of the set-top boxes in a standby state). They are not even updated in a standby state because they deactivate their network interfaces in a standby state. This paper proposes an adaptive standby mode scheduling method for improving the user experience of such boxes. Set-top boxes using the proposed method can analyze the activation pattern and find the frequently used time period (that is, when the set-top boxes are frequently activated). They prepare for their activation during this frequently used time period, thereby reducing the activation latency and enabling their update in a standby state.