• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.1
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• pp.36-44
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• 2005

A push pull hood system is frequently applied to control contaminants evaporated from an open surface tank in recent years. Efficiency of push pull hood system is affected by various parameters, such as cross draft, vessel shapes, size of tanks surface, liquid temperature, and so on. Among these, velocity of cross draft might be one of the most influencing factor for determining the ventilation efficiency. To take account of the effect of cross draft velocities over 0.38m/s, a flow adjustment of ${\pm}$20% should be considered into the push and +20% into the pull flow system Although there are many studies about the efficiency evaluation of push pull hood system based on CFDs(Computational Fluid Dynamics) and experiments, there have been no reports regarding the influence of velocities and direction of cross-draft on push-pull hood efficiency. This study was conducted to investigate the influence of cross draft direction and velocities on the capture efficiency of the push-pull ventilation system. Smoke visualization method was used along with mock-up of push-pull hood systems to verify the ventilation efficiency by experiments. When the cross-draft blew from the same origins of the push flows, the efficiency of the system was in it's high value, but it was decreased significantly when the cross-draft came from the opposite side of push flows Moreover, the efficiency of the system dramatically decreased when the cross-draft of open surface tank was faster than 0.4m/s.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.478-480
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• 2008

On this paper, digitally controlled push-pull dc-dc converter and dc-ac inverter for induction motor control are presented, which is used one DSP(digital signal processor). This system has 12V battery input for the push-pull converter, and the push-pull converter generates 300V output for induction motor inverter input. In order to compensate the push-pull converter, the transfer function of push-pull converter is derived and digital PI compensator is adapted. Through bode diagram, stability of digital controlled push-pull converter is analyzed. To verify the proposed system, digital simulation of the induction motor drive using digital push-pull converter are performed.

• Korean Management Science Review
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• v.10 no.2
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• pp.121-143
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• 1993

Traditional Manufacturing method is push system by plan made in advance and Japanese manufacturing method represented by JUST-IN-TIME is pull system which respond's to the demand flexibly. Both have their pros and cons. In general, it is well understood that push system is faster than pull system in the sense of manufacturing speed. However, pull system such as JIT excelles dramatically in the sense of work in process. Therefore, this paper is trying to put together to get alternative which has the advantage of both system. The objective of the paper is to enhance the effect of built-in manufacturing system without paying extra cost by way of introducing the alternative of the pull-push manufacturing strategic operational method.

• Journal of Digital Convergence
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• v.13 no.11
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• pp.427-432
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• 2015

Recently, Mobile Social Network Game market has grown rapidly because Smart devices has been spreading to many people and improving performance. Push notification, which is a success factor of the mobile social network game brought about stress to the user. However, there is no study on push notifications in the mobile social network game; it was difficult to understand for the use of push notifications. The Games of Kakao talk platform has various push notification system and provides detailed descriptions. On the other hand, the game linked to Facebook has minimal push notification system. In the future, if game companies develop push notification system by the characteristics of user, mobile social network games be able to derive the user's use continuously.

• Journal of Welding and Joining
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• v.31 no.3
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• pp.39-43
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• 2013

It is difficult to feed welding wire stably, when the distance between welding wire feeder and welding torch is far enough. In order to solve this problem, arranging a extension wire feeder between them could be one of useful methods. However, the welding wire could be twisted up in the extension cable between extension and terminal wire feeders in the case that RPM of extension wire feeding motor is higher than that of terminal motor. In this study, feeding problem of normal push-pull wire feeding system occurred at low welding current range less than 250A. In order to solve the problem, two new wire feeding systems of push-pull type were introduced. Welding wire feeding tests were preformed in the range of 150A to 400A with the developed push-pull feeding system. In addition, weldability test was performed at the welding current of 200A, 300A, and 400A. The welding wire twisting problem that was observed in the normal feeding system did not occur in the new push-pull wire feeding system.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.1033-1034
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• 2015

A message transmission method in Push fashions over the Internet has a limit repidly to manage task and support system in a remote control site that has received a risk information. This paper proposes a push notification structure based on the quality of service(QoS) in order to send the diversity disaster informations toward the remote site. As the proposed structure accommodated the previous heterogeneous system, it provides internet services.

• 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.

• Journal of Korean Institute of Industrial Engineers
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• v.31 no.4
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• pp.297-302
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• 2005

Kopzon and Weiss adopted the notion of push-pull into the queueing system recently. We extend this queueing system to the ($N_1,N_2$)-policy version such that the original system corresponds to the special case $N_1=N_2=1$. For the extended system, we perform the cycle analysis and obtain the PGF of the stationary number of customers in the system.

• Journal of Internet Computing and Services
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• v.2 no.3
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• pp.19-25
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• 2001

An educational system using computers was first conceptualized by Dr. Donald Bitzer in the University of Illinois in the late 1950s. Since the PLATO system was developed in 1961, multilateral research were made for the last 30 years. Especially, the development of Internet and Information Technology has contributed to the advancement of the distance education system. This system has greatly changed the existing educational paradigm, As the result, new education system is being realized, This study suggests a distance education system based on ‘push’ technique, which is a means of active information transmission, In this system, the ‘push’ technique is combined with the existing distance education system. Through the combination, learning contents can be provided for learners without connecting the DB on the Internet. In addition, the process of getting new information is real-timed operation. Also, the treatment of item; and the algorithm of level-based item evaluation are devised in consideration of various levels of learners, so that evaluation of items appropriate to the levels of learners can be accomplished.

• Journal of Digital Convergence
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• v.13 no.3
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• pp.193-199
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• 2015

PUSH technology is a technology that can transfer server information without user's request and it is very useful in various areas along with mobile applications. This paper suggest a suitable application model that can utilizes the PUSH technology and mobile devices by finding a useful area. For this, AdMan, a mobile application which can utilize the PUSH technology and mobile devices has been developed. AdMan is a mobile application that developed once and can be able to run on both Android and iOS based mobile devices, since it was developed by using a tool called m-Bizmaker. AdMan is a customer management and advertisement system that can bring big efficiency by utilizing the PUSH technology and mobile application under the today's mobile environment, and it is a good model of ICT technology application of modern society. As an application that can maximize the utilization of the PUSH technology and mobile devices, AdMan can realize better effectiveness if it run on a PUSH server.