• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.14 no.4
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• pp.65-72
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• 2000

This paper proposes a Push type High Frequency DC-DC Converter using Zero Voltage Switching to reduce turn on and off loss at the switching instants. This paper has a advantage which is able to operating safely in load short, because DC reactor is connected with resonance reactor in order to supply a fixed safely in load short, because DC reactor is connected with resonance reactor in order to supply a fixed current with low ripple from DC power supply. The capacitor $(C_1, C_2)$ connected in switch are a common using as resonance capacitor and ZVS capacitor. The analysis of the proposed high frequency resonance DC-DC converter is generally described by using normallized parameter, and we has evaluated characteristic values which is needed to design a circuit. We conform a rightfulness of theoritical analysis by comparing a theoretical values and experimental values obtained from experiment using MOSFET as switching devices.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6A
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• pp.661-669
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• 2009

Various kinds of shear connectors such as headed stud, channel, perforated steel plate and others are commonly used to transfer stress and conduct composite performance in steel concrete composite structures, and many researches have been conducted to improve the characteristics of different types of shear connectors. It is focused in this study on the pull-out and pushout performance of steel pipe pile cap with the open type perfobond for the composite connection to the spread footing. A parameter analysis was conducted, using ABAQUS, a nonlinear finite element analysis program, to obtain data for determining the characteristics of the structure and to allow various parametric analyses of steel pipe cap with the open perfobond.

• Proceedings of the KIEE Conference
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• 2003.11b
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• pp.27-30
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• 2003

Wireless power transmission system is one of the very interesting field not only in a technical and economical point of view but also that people are still trying to realize lossless power transmission. This paper has a purpose on the efficient power transmission at the passive type ICcard by using wireless power transmission system. The most difficult but important part of the passive type RF-ID system is building the system that supplies power from Reader-antenna to IDcard-antenna. To check what is the most efficient way to deliver power depending on what kind of specifications of the power-amp in reader, antenna and antenna in IDcard is for operating IDcard circuit efficiently receiving the power from reader-antenna. For this, we used 125kHz sinewave for RF signal as a basic specification, power-amp : OP-Amp for amplifying signal and AB Class push-pull power-amp for amplifying power, loop type antenna.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.6
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• pp.717-723
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• 2007

Statement of problem. Unreasonable distal cantilevered implant-supported prosthesis can mask functional problems of reconstruction temporarily, but it can cause serious strain and stress around its supported implant and surrounding alveolar bone. Purpose. The purpose of this study was to evaluate strain of implants supporting distal cantilevered fixed prosthesis with two different cantilevered length under distal cantilevered static load. Material and methods. A partially edentulous mandibular test model was fabricated with auto-polymerizing resin (POLYUROCK; Metalor technologies, Stuttgart, Swiss) and artificial denture teeth (Endura; Shofu inc., Kyoto, Japan). Two implants-supported 5-unit screw-retained cantilevered fixed prosthesis was made using standard methods with Type III gold alloy (Harmony C&B55; Ivoclar-vivadent, Liechtenstein, Germany) for superstructure and reinforced hard resin (Tescera; Ivoclar-vivadent, Liechtenstein, Germany) for occlusal material. Two strain gauges (KFG-1-120-C1-11L1M2R; KYOWA electronic instruments, Tokyo, Japan) were then attached to the mesial and the distal surface of each standard abutment with adhesive (M-bond 200; Tokuyama, Tokyo, Japan). Total four strain gauges were attached to test model and connected to dynamic signal conditioning strain amplifier (CTA1000; Curiotech inc., Paju, Korea). The stepped $20{\sim}100$ N in 25 N increments, cantilevered static load 8mm apart (Group I) or 16mm apart (Group II), were applied using digital push-pull gauge (Push-Pull Scale & Digital Force Gauge, Axis inc., Seoul, Korea). Each step was performed ten times and every strain signal was monitored and recorded. Results. In case of Group I, the strain values were surveyed by $80.7{\sim}353.8{\mu}m$ in Ch1, $7.5{\sim}47.9{\mu}m/m$ in Ch2, $45.7{\sim}278.6{\mu}m/m$ in Ch3 and $-212.2{\sim}718.7{\mu}m/m$ in Ch4 depending on increasing cantilevered static load. On the other hand, the strain values of Group II were surveyed by $149.9{\sim}612.8{\mu}m/m$ in Ch1, $26.0{\sim}168.5{\mu}m/m$ in Ch2, $114.3{\sim}632.3{\mu}m/m$ in Ch3, and $-323.2{\sim}-894.7{\mu}m/m$ in Ch4. Conclusion. A comparative statistical analysis using paired sample t-test about Group I Vs Group II under distal cantilevered load shows that there are statistical significant differences for all 4 channels (P<0.05).

• Journal of the Society of Disaster Information
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• v.14 no.3
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• pp.288-295
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• 2018

Purpose: The paper aims to compare the effectiveness of the two types of transport demand management measures, namely pull measures and push measures. Method: Case studies of two metropolitan areas in the developing world assess the extent to which increases in fuel prices can contribute to reducing automobile use and increasing the public transport use and the potential of urban rail transit to cause mode shift from automobiles. Within the case studies, a stated response survey of current car users has been conducted for Cairo and an on-line survey of rail transit users in Algiers. Results: There was a major proportion of car drivers who intend to switch to public transport, depending on the range of fuel prices in Cairo and a considerable proportion of rail users who have switched from automobiles resulting in a measurable reduction in CO2 emissions in Algiers. Conclusion: Investments in urban rail can be highly effective where there are demands for better public transport, but this type of pull measures can be much more effective if combined with push measures which significantly raise driving costs.

• Journal of Intelligence and Information Systems
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• v.22 no.1
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• pp.19-41
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• 2016

Recently, the proliferation of mobile devices such as smartphones and tablet personal computers and the development of information communication technologies (ICT) have led to a big trend of a shift from single-channel shopping to multi-channel shopping. With the emergence of a "smart" group of consumers who want to shop in more reasonable and convenient ways, the boundaries apparently dividing online and offline shopping have collapsed and blurred more than ever before. Thus, there is now fierce competition between online and offline channels. Ever since the emergence of online shopping, a major type of multi-channel shopping has been "showrooming," where consumers visit offline stores to examine products before buying them online. However, because of the growing use of smart devices and the counterattack of offline retailers represented by omni-channel marketing strategies, one of the latest huge trends of shopping is "webrooming," where consumers visit online stores to examine products before buying them offline. This has become a threat to online retailers. In this situation, although it is very important to examine the influencing factors for switching from online shopping to webrooming, most prior studies have mainly focused on a single- or multi-channel shopping pattern. Therefore, this study thoroughly investigated the influencing factors on customers switching from online shopping to webrooming in terms of both the "search" and "purchase" processes through the application of a push-pull-mooring (PPM) framework. In order to test the research model, 280 individual samples were gathered from undergraduate and graduate students who had actual experience with webrooming. The results of the structural equation model (SEM) test revealed that the "pull" effect is strongest on the webrooming intention rather than the "push" or "mooring" effects. This proves a significant relationship between "attractiveness of webrooming" and "webrooming intention." In addition, the results showed that both the "perceived risk of online search" and "perceived risk of online purchase" significantly affect "distrust of online shopping." Similarly, both "perceived benefit of multi-channel search" and "perceived benefit of offline purchase" were found to have significant effects on "attractiveness of webrooming" were also found. Furthermore, the results indicated that "online purchase habit" is the only influencing factor that leads to "online shopping lock-in." The theoretical implications of the study are as follows. First, by examining the multi-channel shopping phenomenon from the perspective of "shopping switching" from online shopping to webrooming, this study complements the limits of the "channel switching" perspective, represented by multi-channel freeriding studies that merely focused on customers' channel switching behaviors from one to another. While extant studies with a channel switching perspective have focused on only one type of multi-channel shopping, where consumers just move from one particular channel to different channels, a study with a shopping switching perspective has the advantage of comprehensively investigating how consumers choose and navigate among diverse types of single- or multi-channel shopping alternatives. In this study, only limited shopping switching behavior from online shopping to webrooming was examined; however, the results should explain various phenomena in a more comprehensive manner from the perspective of shopping switching. Second, this study extends the scope of application of the push-pull-mooring framework, which is quite commonly used in marketing research to explain consumers' product switching behaviors. Through the application of this framework, it is hoped that more diverse shopping switching behaviors can be examined in future research. This study can serve a stepping stone for future studies. One of the most important practical implications of the study is that it may help single- and multi-channel retailers develop more specific customer strategies by revealing the influencing factors of webrooming intention from online shopping. For example, online single-channel retailers can ease the distrust of online shopping to prevent consumers from churning by reducing the perceived risk in terms of online search and purchase. On the other hand, offline retailers can develop specific strategies to increase the attractiveness of webrooming by letting customers perceive the benefits of multi-channel search or offline purchase. Although this study focused only on customers switching from online shopping to webrooming, the results can be expanded to various types of shopping switching behaviors embedded in single- and multi-channel shopping environments, such as showrooming and mobile shopping.

• Proceedings of the KIPE Conference
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• 2003.07a
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• pp.260-263
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• 2003

When ICP(Inductive Coupled Plasma type etching and wafer manufacturing is being processed in semiconductor process, a noxious gas in PFC and CFC system is generated. Gas cleaning dry scrubber is to remove this noxious gas. This paper describes a power source device, 2MHz switching frequency class 2kW RF Generator, used as a main power source of the gas cleaning dry scrubber. The power stage of DC/DC converter is consist of full bridge type converter with 100kHz switching frequency Power amplifier is push pull type inverter with 2MHz switching frequency, and transmission line transformer. The adequacy of the circuit type and the reliability of generating plasma in various load conditions are verified through 50$\Omega$ dummy load and chamber experiments result.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.9
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• pp.834-843
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• 2016

In this paper, the design of a PIN diode S-band transfer-type SP4T including its driver circuit is presented. Each path of the SP4T is composed of the cascade connection of series-shunt PIN diodes to improve the isolation performance. The SP4T is implemented using chip type PIN diodes and a 20 mil AIN substrate fabricated using thin film technology. The driver circuit for the SP4T is designed using a multiplexer and four NMOS-PMOS push-pull pair. From on-wafer measurement, the fabriacted SP4T shows a maximum insertion loss of 1.1 dB and a minimum isolation of 41 dB. The time performance of the driver circuit is evaluated using the packaged PIN diodes with the identical PIN diode chip, and the transition time for on-off and off-on are below 100 nsec. For an input power level of 150 W, the measured insertion loss and isolation are close to those of the on-wafer measurement taking into consideration of the coaxial package mismatch and insertion loss.

• Proceedings of the KIEE Conference
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• 2001.07b
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• pp.880-882
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• 2001

A moving-coil-type linear oscillatory actuator is consisted of the NdFeB permanent magnets with high specific energy as the stator, a coil-wrapped nonmagnetic hollow rectangular structure and an iron core as a pathway for magnetic flux. The inductance of moving coil and the push/pull effect is obtained from the permeance model of LOA with the open magnetic circuit. The analytical method are verified using the 2D finite element method.

• Journal of the Optical Society of Korea
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• v.16 no.1
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• pp.47-52
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• 2012

The use of a $Ti:LiNbO_3$ symmetric Mach-Zehnder interferometric intensity modulator with a push-pull lumped electrode and a plate-type probe antenna to measure an electric field strength is described. The modulator has a small device size of $46{\times}7{\times}1mm$ and operates at a wavelength of $1.3{\mu}m$. The output characteristic of the interferometer shows the modulation depth of 100% and 75%, and $V_{\pi}$ voltage of 6.6 V, and 6.6 V at the 200 Hz and 1 KHz, respectively. The minimum detectable electric field is ~1.84 V/m, ~3.28 V/m, and ~11.6 V/m, corresponding to a dynamic range of about ~22 dB, ~17 dB, and ~6 dB at frequencies of 500 KHz, 1 MHz and 5 MHz, respectively.