• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.12
• /
• pp.5028-5057
• /
• 2015

In this paper, a new mathematical scheme of Macro Handover Management (MHM) in F-HMIPv6 networks based on Location Based Services (LBS) is proposed. Previous schemes based on F-HMIPv6 protocol usually suffer from three major drawbacks: First, They don't exploit the information about the user mobility behavior in order to reduce handover effects. Second, they only focus on the micro mobility level. Third, they don't consider the quality of service (QoS) of the traffic. The proposed MHM scheme avoids these drawbacks using the available information about Mobile Node (MN) such as user mobility patterns and MN's velocity to predict handover and improve network's QoS. It also takes the traffic type in consideration since it presents a major factor in locating QoS for the user. MHM is analyzed and compared with the F-HMIPv6. The results show that MHM improves the performance in terms of packet delivery cost, location update cost, and handover latency. The design of MHM comprises software package in the MN in addition to a hardware part in the network side. It has implications for communication, design, and pricing of mobile services.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.17 no.3
• /
• pp.561-566
• /
• 2013

In this paper, android phone information push system based on the XMPP protocol is proposed. For this, we implement a XMPP(eXtensible Message and Presence Protocol) based instant message system in C/S network environment by using Java language and eclipse device. This system not only allows sending and receiving messages from the PC server to mobile phone client, but also enables the expansion into the smack package of an android phone. Thus, this system shown, in this paper has the better performance in transmission and transfer speed than those of the basic XMPP protocol system.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.9 no.8
• /
• pp.3103-3120
• /
• 2015

This paper presents a single-phase energy metering chip with built-in calibration function to measure electric power quantities. The entire chip consists of an analog front end, a filter block, a computation engine, a calibration engine, and an external interface block. The key design issues are how to reduce the implementation costs of the computation engine from repeatedly used arithmetic operations and how to simplify calibration procedure and reduce calibration time. The proposed energy metering chip simplifies the computation engine using time-division multiplexed arithmetic units. It also provides a simple and fast calibration scheme by using integrated digital calibration functionality. The chip is fabricated with 0.18-μm six-layer metal CMOS process and housed in a 32-pin quad-flat no-leads (QFN) package. It operates at a clock speed of 4096 kHz and consumes 9.84 mW in 3.3 V supply.

• Journal of the Korean Society of Clothing and Textiles
• /
• v.28 no.5
• /
• pp.559-569
• /
• 2004

The present study attempts to identify the differences in consumer information source, shopping orientation, and store image in the purchase of cosmetics in adult women at the age of 20 or more according to the distributions channels: department stores, specialty stores, discount stores and direct mails. From October 3 to 13, a survey was conducted to 1,200 adult women who visited each channel and who would understand the purpose of this study and complete the questionnaire. 300 sheets were distributed to each of the channels under investigation, and a total of 1,116 questionaaires were used in the final analysis. Using the statistical package, SPSS WIN 10.0, factor analysis, ANOVA, and Duncan's post-hoc test were carried out. The result are as follows: 1. There was a difference in the demographical characteristics of the consumers according to the distribution channels for cosmetics. 2. There was a differen co in the shopping orientations of the consumers according to the distribution channels for cosmetics. 3. There was a difference in the information sources of the consumers according to the distribution channels for cosmetics. 4. There was a difference in the store images perceived by the consumers according to the distribution channels for cosmetics.

• Korean Journal of Agricultural and Forest Meteorology
• /
• v.1 no.2
• /
• pp.135-141
• /
• 1999

The information on agricultural weather over the Korean Peninsula was produced, using the Bio-sphere-Atmosphere Transfer Scheme(BATS). We modified the input and output portions of BATS such that the whole processes can be excuted as a package. Based on this approach, automatic production system of agricultural meteorology information was developed. The results of this model was compared with the observed data. The differences between the model results and observed data for surface temperature, rooting zone temperature and top soil temperature were 2.0$^{\circ}$C, 2.0$^{\circ}$C and 2.6$^{\circ}$C, respectively.

• JSTS:Journal of Semiconductor Technology and Science
• /
• v.14 no.4
• /
• pp.471-477
• /
• 2014

In this paper, a modeling and co-simulation methodology is proposed to predict the radiated electromagnetic interference (EMI) from on-chip switching I/O buffers. The output waveforms of I/O buffers are simulated including the on-chip I/O buffer circuit and the RC extracted on-chip interconnect netlist, package, and printed circuit board (PCB). In order to accurately estimate the EMI, a full-wave 3D simulation is performed including the measurement environment. The simulation results are compared with near-field electromagnetic scan results and far-field measurements from an anechoic chamber, and the sources of emission peaks were analyzed. For accurate far-field EMI simulation, PCB power trace models considering IC switching current paths and external power cable models must be considered for accurate EMI prediction. With the proposed EMI simulation model and flow, the electromagnetic compatibility can be tested even before the IC is fabricated.

• ETRI Journal
• /
• v.38 no.1
• /
• pp.133-140
• /
• 2016

This paper presents a method of parasitic inductance reduction for high-speed switching and high-efficiency operation of a cascode structure with a low-voltage enhancement-mode silicon (Si) metal-oxide-semiconductor field-effect transistor (MOSFET) and a high-voltage depletion-mode gallium nitride (GaN) fielde-ffect transistor (FET). The method is proposed to add a bonding wire interconnected between the source electrode of the Si MOSFET and the gate electrode of the GaN FET in a conventional cascode structure package to reduce the most critical inductance, which provides the major switching loss for a high switching speed and high efficiency. From the measured results of the proposed and conventional GaN cascode FETs, the rising and falling times of the proposed GaN cascode FET were up to 3.4% and 8.0% faster than those of the conventional GaN cascode FET, respectively, under measurement conditions of 30 V and 5 A. During the rising and falling times, the energy losses of the proposed GaN cascode FET were up to 0.3% and 6.7% lower than those of the conventional GaN cascode FET, respectively.

• Journal of Information Science Theory and Practice
• /
• v.2 no.1
• /
• pp.62-70
• /
• 2014

The All India Council for Technical Education (AICTE), an apex body of controlling technical education in India, has made mandatory subscription of e-Resources to all its Engineering College Libraries. This policy has directly helped the teaching community, research scholars, and student's paternity, which has benefits for their teaching, research activities, and curriculum, respectively. This study emphasizes the usefulness of e-Resources among the teachers and scholars of engineering colleges in the Bangalore region under Visvesvaraya Technological University (VTU), Belgaum, Karnataka. Survey methodology has been used as the basic research tool for data collection with the help of questionnaires. 866 teaching faculties in VTU were selected randomly on the basis of willingness of users who access the e-Resources for their academic and research activities in the survey. The survey results were tabulated and analyzed with descriptive statistics methods using the SPSS 20 software package. The findings reveal that e-resources are useful for engineering college teachers and scholars for their academic and research activities.

• The Journal of Information Technology
• /
• v.8 no.3
• /
• pp.73-82
• /
• 2005

The present paper aims to examine the relationship between the online word of mouth(WOM) contents and the WOM effect and to see how receivers' features such as product knowledge and involvement level influence the WOM received. For that purpose, we categorize WOM contents into two subcategories; product news and personal experience. The WOM effect, in turn, is into the WOM received. Survey questionnaires were given to 268 collegians as to their online WOM activities to purchase MP3 players. SPSS 10.0 package was employed as the method of statistical analysis. We report the following results. First, product news is shown to exert a greater effect on the WOM received than personal experience. Second, their product knowledge plays a moderating role in the relationship between the WOM contents and the WOM received. Finally, it is shown that the factor of involvement level moderates the relationship between the WOM contents and the WOM received. The current paper attempts to develop a hypothetical relationship between WOM information and WOM received and to provide a theoretical foundation for the practical online marketing. We must admit the methodological limitations with respect to subjects and samples. It should be worthwhile, however, to compare online and off-line marketing and to expand the range of research in the current line of thought.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.24 no.3
• /
• pp.234-239
• /
• 2011

In this study, the heat transfer capability have been improved by using via-holes in FR4 PCB, when the LED lighting is designed to solve the thermal problem. The thermal resistance and junction temperature were measured by changing the dimension of FR4 PCB and size of via hole. As a result, when the dimension was increased initially, the thermal resistance and junction temperature was decreased rapidly, the ones was stabilized after the dimension of 200 $[mm^2]$. Also, the light output was improved up to maximum 17% by formation of via-hole and expansion of dimension in FR4 PCB. Therefore, the thermal resistance and junction temperature could be improved by expansion of PCB dimension and configuration of via-hole ability.