• Journal of the Korea Safety Management & Science
• /
• v.9 no.6
• /
• pp.155-162
• /
• 2007

Recently, retail store automation appliance market is changed with traditional POS systems techniques and RFID, radio POS system, and self checkout system, etc. in the foreign advanced distribution industry. Retailers and consumers require convenient POS system which can provide more functions and fast service. These requests bring to rapid evolution of various H/W and S/W corresponding with POS system. In this study with the POS systems and the RFID technology we develop core technology of movable u-POS system based on RFID that can use in large store. So we propose u-Cart system that can alternate the current shopping cart and POS terminal and that provide value added services to customer. As the result we present the configuration of u-Cart terminal device(WMDT : Wireless Mobile Data Terminal) including RFID reader module that can provide various information to consumer and some convenient client applications that are running in WMDT and u-POS administration service module.

• Transactions of Materials Processing
• /
• v.23 no.7
• /
• pp.431-438
• /
• 2014

For electromagnetic forming(EMF) the most important feature is a forming coil which creates the electromagnetic force(Lorentz force), using current density and a magnetic field. Most previous papers have concentrated on the final configuration of the blank or the efficiency of EMF process. Studies focused on the design parameters affected by the forming coil performance have not been conducted. In order to design a suitable forming coil for an object, the current study uses LS-DYNA EM-Module to not only optimize the coil but also to examine the effect of coil performance. By this method a suitable forming coil was made and tested to determine whether or not good formability was achieved in a free bulge test Numerical analysis was also used. The workpiece was Al 1100-O with a thickness of 1.27mm and the coil was made from copper CW004A, which has good electrical conductivity and is suitable for electrical components.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.13 no.4
• /
• pp.61-66
• /
• 2013

The central core of the Traffic Management System is an Incident Management System. Whole approach has been component-orientated, with a secondary emphasis being placed on the traffic characteristics at the sites. The first action taken during the development process was the selection of the required data for each components within the existing infrastructure of Algeria freeway system. After review and analysis of existing incident detection methodologies, Paramics was utilized to test the performance of APID, DELOS algorithms. The existing system of Algeria freeway was tested in a different configuration at different sections of freeway, thereby increasing the validity and scope of the overall findings. The incident detection module has been performed according to predefined system validation specifications. The Paramics simulation was done with the use of synchronous analysis, thereby providing a means for testing the incident detection module.

• Journal of Power Electronics
• /
• v.14 no.4
• /
• pp.661-670
• /
• 2014

A new DC/DC converter with zero voltage switching is proposed for applications with high input voltage and high load current. The proposed converter has two circuit modules that share load current and power rating. Interleaved pulse-width modulation (PWM) is adopted to generate switch control signals. Thus, ripple currents are reduced at the input and output sides. For high-voltage applications, each circuit module includes two half-bridge legs that are connected in series to reduce switch voltage rating to $V_{in}/2$. These legs are controlled with the use of asymmetric PWM. To reduce the current rating of rectifier diodes and share load current for high-load-current applications, two center-tapped rectifiers are adopted in each circuit module. The primary windings of two transformers are connected in series at the high voltage side to balance output inductor currents. Two series capacitors are adopted at the AC terminals of the two half-bridge legs to balance the two input capacitor voltages. The resonant behavior of the inductance and capacitance at the transition interval enable MOSFETs to be switched on under zero voltage switching. The circuit configuration, system characteristics, and design are discussed in detail. Experiments based on a laboratory prototype are conducted to verify the effectiveness of the proposed converter.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2013.10a
• /
• pp.483-488
• /
• 2013

The psychoacoustic quality of ABS is now considered more important than before as the focus of recent ABS function is expanded to basic function from typical emergency function. Thus, the automotive parts manufacturing companies are actively working to improve NVH (Noise, Vibration, and Harshness) in ABS module. In terms of time, test place, and cost, however, it is very inefficient to have all the operating noise validation test in real vehicle configuration especially for partially improved ABS module. To contribute to reducing the development period and to grasping the improvements faster, this research presents the study of a correlation to predict ABS operating noise inside vehicle via HILS rig test. The regression equation in this paper was statistically drawn from using Minitab S/W, and based on that equation, the noise spectrum of vehicle interior was analogized.

• Journal of Biomedical Engineering Research
• /
• v.27 no.4
• /
• pp.197-202
• /
• 2006

Devices in current market to perform electrical stimulation therapy of the urinary incontinence frequent in aging women are very much impractical to us ε due to the wired configuration. The present study implemented new wireless device to enhance self as well as in-hospital therapy with the easiest and the most convenient application. The therapy system consisted of two modules, called 'master' and 'slave', communicating with each other by the wireless Bluetooth protocol. The patient controls therapy processes on the master module in hand, transmitting the required informations to operate the slave module placed within her pants with the viginal electrode connected, delivering appropriate electrical stimulation. Wireless communication enabled self therapy with clothes on, leading to a great convenience for the patient. The stimulation output signal was comparable to commercialized products in both waveform and stimulation capacity.

• Journal of the Korean Solar Energy Society
• /
• v.35 no.1
• /
• pp.1-8
• /
• 2015

In the present study, the effects of the heat spreader thickness and the heat sink size on the thermal performance of a cooling device for a concentrating photovoltaic (CPV) module were numerically investigated. Numerical simulation was conducted by using the simulation tool ICEPAK, commercial software based on the finite volume method. Numerical results were validated by comparing the existing experimental data. The thermal performance of a cooling device, which consisted of a heat spreader and a natural convective heat sink, was evaluated with varying the heat spreader thickness and the heat sink size. The geometric configuration of the natural convective heat sink, such as the fin height, the fin spacing, and the fin thickness, was optimized by using the existing correlation. The numerical results showed that the thermal performance of the cooling device increased as the heat spreader thickness or the heat sink size increased. Also, it was found that the spreading thermal resistance plays an important role in the thermal performance of the cooling device which has the localized heat source.

• The Journal of the Convergence on Culture Technology
• /
• v.8 no.2
• /
• pp.355-360
• /
• 2022

In this paper, we present design and developing method for EMS(environment monitoring system) of micro data center. This developing EMS monitors operating environment of micro data center and analyze sensing data through IoT(Internet of things) sensors in real time. Firstly we present configuration method of IoT sensing package and design method EMS hardware platform. Secondly we design data collector software for data collection of IoT sensor with different protocol and develop monitoring software of EMS. The data collector software consists of sensor collector module and collector manager module. Also we design EMS software which has micro service architecture structural style and component based business logic.

• Journal of Biosystems Engineering
• /
• v.43 no.2
• /
• pp.94-102
• /
• 2018

Purpose: In this study, a maintenance free super-capacitor battery charging system based on the photovoltaic module, to be used in agricultural electric carriers, was developed and its charging characteristics were studied in detail. Methods: At first, the electric carrier system configuration is introduced and the electric control components are presented. The super-capacitor batteries and photovoltaic module used in the experiment are specified. Next, the developed charging system consisting of a constant current / constant voltage Buck converter as the charging device and a super-capacitor cell as a balancing device are initiated. The proposed circuit design, a developed PCB layout of each device and a proportional control to check the current and voltage during the charging process are outlined. An experiment was carried out using a developed prototype to clarify the effectiveness of the proposed system. A power analyzer was used to measure the current and voltage during charging to evaluate the efficiency of the energy storage device. Finally, the conclusions of this research are presented. Results: The experimental results show that the proposed system successfully controls the charging current and balances the battery voltage. The maximum voltage of the super-capacitor battery obtained by using the proposed battery charger is 16.2 V, and the maximum charging current is 20 A. It was found that the charging time was less than an hour through the duty ratio of 95% or more. Conclusions: The developed battery charging system was successfully implemented on the agricultural electric carriers.

• The Journal of the Korea Contents Association
• /
• v.18 no.3
• /
• pp.309-319
• /
• 2018

SELinux is used for system level security in various systems using Linux, and is now being used for device security such as IoT. However, since SELinux has inherent problems of execution time degradation, various studies have been conducted to solve this problem. In this paper, we show that performance can be improved through policy reconfiguration in the environment where the loadable module policy method, which is a general method using SELinux, is applied. By reconfiguring the access query table through the Priority-TE policy that gives priority to the type, it is possible to provide faster execution time for types requiring faster access query performance. This paper introduces the differences between SELinux policy configuration method in Monolithic environment and performance analysis. This can be used as a reference by security administrators or developers in applying SELinux.