• Journal of Broadcast Engineering
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• v.5 no.1
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• pp.130-138
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• 2000

The paper describes a push system, a broadcasting system in the internet, which is developed for internet and intranet use. In this paper, we carried out research on the method to support the large number of users in the intranet environment. Particularly the paper analyzes the effects on the network traffic according to the number of the user connected to the push system and the frequency of the connections when push servers are distributed over the intranet. Push system described here uses two different kinds of channels, common channel and local channel. Common channel is the channel to be replicated among the push servers in the intranet. This paper shows that the method using the common channel synchronization is efficient in supporting the large number of intranet users. We introduce an algorithm to make the interconnections between channels efficiently amongpush servers distributed over the intranet.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.9B
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• pp.1635-1640
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• 2000

In this paper, a 18 GHz oscillator is designed with the push-push method an fabricated by semi-MMIC process, in which the second harmonic is the main output signal with the suppressed fundamental mode. In semi-MMIC process, passive components with microstrip transmission line are implemented using MMIC process on semi-insulating GaAs substrate. Then, chip types of P-HEMT, resistors, and capacitors are connected through Au wire-bonding. Also, the ground plane is inserted around the circuit and connected each other with the back-side of substrate through Au wire-bonding instead of via-hole. The semi-MMIC push-push oscillator shows the output powder of -10.5 dBm, the fundamental frequency suppression of -17.3 dBc/Hz, and the phase noise of -97.9 dBc/Hz at the offset frequency of 100 kHz.

• Journal of Satellite, Information and Communications
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• v.12 no.2
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• pp.33-37
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• 2017

This paper suggests a new reliable push pull converter. The proposed push-pull converter have additional two diodes comparing with conventional push-pull converter. When one of two MOSFETs of the push-pull converter is on state, the other MOSFET is automatically off state due to adding additional diodes. Therefore, the converter is under electric noise environments, the converter avoids short circuit due to turning on of two MOSFETs. In this paper, the suggested converter has been simulated by PLECS software for 100 kHz switching frequency. In simulation, the current of the converter switches increases about 10 % for $20{\mu}sec$ electric noise environments. However, the converter operates very reliably without any short circuit conditions.

• The Journal of Korean Physical Therapy
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• v.28 no.3
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• pp.195-200
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• 2016

Purpose: This study was designed to evaluate the effects of the different condition of leg support surface on the upper extremity and core muscle activity during the push-up exercise. Methods: Fifteen healthy subjects that were practicable push-ups were recruited in this study. Subjects were instructed the push-up exercise in the different condition of the leg support surface. Each condition of support surface was set to the high and lower, and the unstable and stable condition. Muscle activation was measured by using the surface electromyography (EMG), and recorded from the triceps brachii, serratus anterior, latissimus dorsi, rectus abdominis, abdominal external oblique, and erector spinea muscle. Results: In the results of experiments, there was no significant difference of muscle activation in upper extremity between the high unstable and high stable support surface. By contrast, muscle activation of the rectus abdominis and abdominal external oblique was significantly higher in the low unstable support surface, compared with those of the low stable support surface. It is well known that the core muscle was important to stabilization of trunk stability. Conclusion: This result demonstrates that the low and unstable support surface for the lower extremity was suited for training of core muscle for trunk stabilization during the push-up exercise.

• Journal of the Korean Society of Physical Medicine
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• v.4 no.4
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• pp.269-274
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• 2009

Purpose：The purpose of this study is an interval palmar width according to change of muscle activation under push-up movement. Methods：Three, this study participation normal young adult (male 3, mean age ; 24yaers). The subject performed maximum contraction under push-up movement. EMG activaty patterns is measured with three different width. The EMG activity of pectoralis major and latissimus dorsi were measured using surface electromyography. Results：EMG activation of pectoralis major and latissimus dorsi following of push-up was shown significant difference(p<.05). Also, experiment value was agree with calculation value and width of shoulder position was minimum of pectoralis major and latissimus dorsi muscle activity. Conslusion：RMS values in case of fretum and wide width of the hands on Latissimus Dorsi are shown muscle activity $132{\mu}V$ and $173.5{\mu}V$, respectively. Especialy, RMS value in terms of wide width of the hands on muscles is shown very enhanced muscle activity. It is suggest that interval palmar width of the hands on pectoralis major and latissimus dorsi in push-up movement was effective to intensify of the muscle activity.

• Journal of the Korean Society of Food Culture
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• v.24 no.4
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• pp.401-412
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• 2009

The aims of study were to provide basic data for the internationalization of Contract Foodservice Management Companies (CFMC) and to gain a better understanding of internal push-and-pull factors through in-depth interviews. The interviewees were managers of four large CFMCs and one small-to-medium CFMC. The non-structured interview format employed an interview guide of open-ended questions. All interviews were digitally recorded and notes were taken simultaneously by an interview assistant. The narrative data analysis involved transcription, coding, classification by categories, and content analysis. Eighty-eight codes were generated from the interview analyses, and the subordinate variables uncovered included seven push factors, eight pull factors, one interactive factor, and 10 internal dynamics. These factors will be useful in further studies of the internal operations of specific CFMCs, and more generally, the practical condition of the industry.

• Journal of Distribution Science
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• v.16 no.9
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• pp.65-77
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• 2018

Purpose - A trading area is very closely related to consumer life. A trading area is a cultural and social space that consumes culture and promotes human relationships as well as an economic space where consumers live their daily lives. In this context, a trading area research should be conducted objectively and empirically because it deals with the activities of consumer's life. The purpose of this study is to identify the intrinsic psychological motivation(push motivation) caused when consumers visit a trading area and to demonstrate how the push motivation for a trading area influence on consumer's flow, satisfaction, revisit intention. Research design, data, and methodology - In order to develop research hypotheses for this study, the development procedures for push motivation scale are as follows; (1) generating initial pool of items based on previous studies, (2) expert judgement to evaluate content and face validity, and (3) assessing convergent and discriminant validity using confirmatory factor analysis. In order to achieve these purposes, online surveys were conducted on frequent or familiar visitors to the trading areas around the Gangnam, Kunkuk University and Hongik University Station. Among the 1,343 questionnaires collected, 1,157 cases were analyzed by using SPSS 22.0 and SmartPLS 3.0 statistical package program, except for 186 responses in which responses were judged to be unfaithful. Results - The push motivation was classified into five sub-dimensions of excitement/stimulus, rest/relaxation, exit/refreshing, knowledge/learning and human relationship promotion as multidimensional and complex factors composed of individual and social-related dimensions. The excitement/stimulus and human relationship promotion of push motivation have positive effects on satisfaction. However, all dimensions of the push motivation have positive effects on flow. And flow has a positive effect on satisfaction and revisit intention. Meanwhile, the mediation test using boostrapping shows that flow plays a full mediating role in the relationship between rest/relaxation, exit/refreshing, knowledge/learning and satisfaction, but a partial mediating rol e between excitement/stimulus, human relationship promotion and satisfaction. Finally, satisfaction plays a partial mediating role between flow and revisit intention. Conclusions - This study shows that the push motivation is multidimensional and compositive depending on the situation of a consumer. In addition, it is found that the human relationship promotion(a social-related motivation) has a much more important effect on flow and satisfaction than other push motivations of individual dimensions. It also shows that satisfaction increases when consumers are being flowed at their visit and degree of revisit intention also grows as satisfaction increases. As implications of this study, a marketer should try to understand consumer's visit motivation at first and then develop factors that increase their flow, satisfaction, revisit intention. It also requires a marketer to approach subjects on a trading area more objectively and empirically based on the psychology and behavior of consumers, in order to establish a proper and efficient strategy on development of a trading area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.624-631
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• 2017

This study aimed to identify the effect of the push-up plus exercise with sling on the muscle activity and lung function in adults with forward head posture over a period of 8 weeks. A total of 16 adults with forward head posture were recruited. The participants were divided into two groups : control (n-=8) and experimental (n=8). From July 6 until Aug 28, 2015, the participants were instructed to perform the knee push-up plus exercise and knee push-up plus using sling exercise three times a week to begin with and progressing to three sets of push-ups on each occasion after 8 weeks. The participants in both groups showed an increase in their craniovertebral angle (both groups p<0.001) and a decrease in their crania rotation angle (control p<0.05, experimental p<0.001). The participants in both groups showed a decrease in their trapezius activity (both groups p<0.001), an increase in their serratus anterior and lower trapezius muscle activity (both groups p<0.001), (and an increase in their) lung function (control group p<0.01, experimental group p<0.001). These findings show that push-up plus exercise improves posture and increases activation of lung function, while the push-up plus exercise in the sling is more effective in improving the forward head posture. The push-up plus exercise in the sling was more effective in improving the forward head posture, but there was no significant difference in the lung function between the two groups. Therefore, the push-up plus exercise in the sling is recommended as an exercise that is effective for the improvement of the posture and lung function of persons with forward head posture.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.3
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• pp.49-54
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• 2016

PURPOSE: This study was implemented to measure the muscle activity of muscles surrounding shoulder during push-up exercise according to the slope angle. METHODS: This study has research subject consisting of 25 normal male adults without neurologic or musculoskeletal injury in shoulder part. EMG was used as a tool for measuring muscle activity and four muscles including upper trapezius (UT), middle trapezius (MT), Lower Trapezius (LT), and Serratus Anterior (SA) were chosen for measuring the muscle activity of muscles surrounding shoulder. Tilting table slope was set at $0^{\circ}$, $30^{\circ}$, $45^{\circ}$, and $60^{\circ}$ and push-up motion was performed three time for each case to use the average value. The measured value was used after generalization process to create %RVC value where the measured value was standardized by using $0^{\circ}$ as a standard. RESULTS: There was a difference of muscle activity according to the tilting table slope during push-up exercise. In UT, MT, and SA, there was no significant $0^{\circ}$ and $30^{\circ}$, $45^{\circ}$ and $60^{\circ}$. But there was significant $30^{\circ}$ and $45^{\circ}$. LT was significant difference between $45^{\circ}$ and $60^{\circ}$ (p<.05). CONCLUSION: There are cases where push-up exercise should be selectively implemented due to shoulder problems. According to this results between $0^{\circ}$ and $30^{\circ}$, push up will be able to more effectively exercise. Applying proper angle of tilting table for push-up to patients who have difficulties in performing motions along with physical consumption can deliver effective and easy exercise program.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.3
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• pp.290-301
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• 2006

A push pull hood system is frequently applied to control contaminants evaporated from an open surface tank. Efficiency of push pull hood system is affected by various parameters, such as, cross draft, vessel shapes, tank surface area, liquid temperature. A previous work assisted by flow visualization technique qualitatively showed that a strong cross draft blown from the pull hood to push slot could destroy a stable wall-jet on the surface of tank, resulting in the abrupt escape of smoke from the surface. In this study, the tracer gas method was applied to determine the effect of cross-draft on the capture efficiency qualitatively. A new concept of capture efficiency was introduced, that is, linear efficiency. This can be determined by measuring the mass of tracer gas in the duct of pull hood while the linear tracer source is in between push slot and pull hood. By traversing the linear tracer source from the push slot to the pull hood, it can be found where the contaminant is escaped from the tank. Total capture efficiency can be determined by averaging the linear efficiencies. Under the condition of cross-draft velocities of 0, 0.4, 0.75, 1.05 and 1.47m/s, total capture efficiencies were measured as 97.6, 95.4, 94.6, 92.7 and 70.5% respectively. The abrupt reduction of efficiency with cross-draft velocity of 1.47m/s was due to the destruction of tank surface wall-jet by the counter-current cross-draft. The same phenomenon was observed in the previous flow visualization study. As an alternative to overcome this abrupt efficiency drop, the 20% increase of hood flow rates was tested, resulting in 20% efficiency increase.