• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.27 no.3
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• pp.239-245
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• 2016

Deramping technique has been widely used to acquire high resolution SAR(Synthetic Aperture Radar) images for the advantage of the data size and the processing time. However, unwanted spurious signals caused by SAR hardware can be leaked in the process of converting into a digital signal through the ADC(Analog-Digital Converter) and added in a echo signal. These tones make image quality degrade significantly. In order to solve this problem, the unwanted tones need to be detected by analysing the characteristic of the noise tone and then effectively removed from raw data. In this paper, we propose a method for efficiently removing noise tone on the raw data based on the characteristic of spurious signals.

• Journal of Biosystems Engineering
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• v.14 no.4
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• pp.221-228
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• 1989

A data acquisition system was designed to measure the forces on a rolling coulter in three coordinated directions, angular velocity of the coulter and travel speed of a soil bin. The data acquisition system consisted of a dynamometer, speed transducers, a signal conditioner, an inter-face board, an Aim-65 microcomputer and a digital data recorder. Strain gages were attached on the surface of the dynamometer and connected to form three Wheatstone bridges, which measure the draft force, the vertical force and the side force on the coulter. An interaction among three dimensional forces was found during the calibration. A matrix procedure was used to correct the forces for this interaction. Rotary shaft encoders were mounted on the coulter and on the soil bin drive to measure the angular velocity of the coulter and the travel speed of the soil bin. The angular velocity and the travel speed were computed by counting the number of pulse signals from the rotary shaft encoders every 0.2 second. The digital signals from the rotary shaft encoders were connected to counters and the analog signals from the dynamometer, after passing through the signal conditioner, were connected to the A/D converter. The microcomputer programs, written in assembly language, were developed to read signals from the transducers, convert them to actual unit, display them upon request and record them on a sigital tape every 0.2 second.

• The Journal of the Korea institute of electronic communication sciences
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• v.2 no.2
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• pp.83-91
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• 2007

The purpose of this paper is developing a PML server which is capable of saving and managing effectively the information of vehicles using RFID technology in the logistical and distributive environment. The PML server logs and manages the real-time static and dynamic information about the vehicles in EPC code format which is represented by XML schema and transmitted by the RFID reader to the server. It receives information from SAVANT the RFID middleware and transmits the data to the traffic information management application The main system we developed consists of the EPC data registry, query processor, data converter, vehicle product and instance data storage, system management tool and application API parts.

• Journal of Power Electronics
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• v.10 no.6
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• pp.611-620
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• 2010

This paper presents a new architecture, called "Power Electronics Remote Wiring and Measurement Laboratory (PermLAB)", that translates a common gateway interface (CGI) string from a remote web user to a web server connected to a 3-dimension switching matrix board, can be used to switch on and off, and to control a cluster of instruments and components. PermLAB addresses real-time connection, switching, and data acquisition over the Internet instead of using simulated data. A software procedure uses a signature system to identify each instrument and component in a complex system. The Web-server application is developed in HTML, JavaScript and Java, and in C language for the CGI interface, which resides in a controller portion of LabVIEW. The LabVIEW software fully integrates the Web sever, LabVIEW data acquisition boards and controllers, and the 3-dimensional switching matrix board. The paper will analyze a half-wave rectifier (AC - DC converter) circuit connected over the Internet using the PermLAB. PermLAB allows students to obtain real data by real-time wiring of real circuits in the laboratory using a "virtual breadboard" on the Web. The software for the Web-based 3-dimensional system is flexible, portable, can be integrated into many laboratory applications or expanded, and easily accessible worldwide.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.3
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• pp.401-409
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• 2023

Oscillating water column (OWC) type wave power generator system is a power generation system that uses wave energy, a sustainable and renewable energy source. Irregular cycles and wave heights act as factors that make it difficult to secure generation efficiency of the wave power generator system. Recently, research for improving power generation efficiency is being conducted by applying digital twin technology to OWC type wave energy converter system. However, digital twin using sensor data can predict erroneous performance due to uncertainty in the sensor data. Therefore, this study proposes an uncertainty analysis method for sensor data which is used in digital twin to secure the reliability of digital twin prediction results. Uncertainty quantification considering sensor data characteristics and future uncertainty information according to uncertainty propagation were derived mathematically, and confidence interval estimation was performed based on the proposed method.

• Journal of Korea Multimedia Society
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• v.20 no.2
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• pp.352-362
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• 2017

This paper proposes an algorithm for automatically converting and displaying rainfall radar data on a 3D GIS platform. The weather information displayed like rainfall radar data is updated frequently and large-scale. Thus, in order to efficiently display the data, an algorithm to convert and output the data automatically, rather than manually, is required. In addition, since rainfall data is extracted from the space, the use of the display image fused with the 3D GIS data representing the space enhances the visibility of the user. To meet these requirements, this study developed the Auto Data Converter application that analyzes the raw data of the rainfall radar and convert them into a universal format. In addition, Unity 3D, which has good development accessibility, was used for dynamic 3D implementation of the converted rainfall radar data. The software applications developed in this study could automatically convert a large volume of rainfall data into a universal format in a short time and perform 3D modeling effectively according to the data conversion on the 3D platform. Furthermore, the rainfall radar data could be merged with other GIS data for effective visualization.

• Journal of Biosystems Engineering
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• v.7 no.2
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• pp.18-29
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• 1983

A low cost and versatile data acquisition system for the field and laboratory use was developed by using a single board microcomputer. Data acquisition system based on a Z80 microprocessor was built, tested and modified to obtain the present functional system. The microcomputer developed consists of 6 kB ROM, 5 kB RAM, 6-seven segment LED display, 16-Hex. key and 8 command key board. And it interfaces with an 8 channel, 12 bits A/D converter, a microprinter, EPROM programmer for 2716, and RS232C interface to transfer data between the system and HP3000 mini-computer manufactured by Hewlett Packard Co., A software package was also developed, tested, and modified for the system. This package included drivers for the AID converter, LED display, key board, microprinter, EPROM programmer, and RS232c interface. All of these programs were written in 280 assembler language and converted to machine codes using a cross assembler by HP3000 computer to the system during modifying stage by data transferring unit of this system, then the machine language wrote to the EPROM by this EPROM programmer. The results are summarized as follows: 1. Measuring program developed was able to control the measuring intervals, No. of channels used, and No. of data, where the maximum measuring speed was 58.8 microsec. 2. Calibration of the system was performed with triangle wave generated by a function generator. The results of calibration agreed well to the test results. 3. The measured data was able to be written into EPROM, then the EPROM data was compared with original data. It took only 75 sec. for the developed program to write the data of 2 kB the EPROM. 4. For the slow speed measurements, microprinter instead of EPROM programmer proved to be useful. It took about 15 min. for microprinter to write the data of 2 kB. 5. Modified data transferring unit was very effective in communicating between the system and HP3000 computer. The required time for data transferring was only 1~2 min. 6. By using DC/DC converting devices such as 78-series, 79-series. and TL497 IC, this system was modified to convert the only one input power sources to the various powers. The available power sources of the system was DC 7~25 V and 1.8 A.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.11
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• pp.2081-2093
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• 1994

In this study, we design and implement 64 QAM demodulator which has 155 Mbps, first level of CCITT G707 SDH(Synchronous Digital Hierachy) for STM 1 signal transmission. Carrier recovery which effects the demodulator performance uses decision feedback carrier using 8 bits A/D converter. Also, PSF(Pulse Shaping Filter) is 7 order elliptic filter. Carrier recovery circuit is designed and implemented digital type which use high 3 bits of 8 bits conversion data as data and the order low bits as error data and hybrid type which use VCO and analog integrator. Therefore we obtain stable performance recovery.

• Proceedings of the IEEK Conference
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• 2003.07c
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• pp.2839-2842
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• 2003

The paper is proposed for control signals to operate X-ray detector signal acquisition system There are control signals and synchronized signals for data acquisition system. X-ray detector signal acquisition system is divided into pre-treatment part which is to amplify acquired dual 16 channel analog input, converter pan which is to multiplex, and convert data and transmit part that combine transferred data output and address in order. It also describes detailed control signals.

• Journal of information and communication convergence engineering
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• v.13 no.4
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• pp.235-240
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• 2015

A decimation chain for multi-standard reconfigurable radios is presented for 900-MHz and 1,900-MHz dual-band cellular standards with a data interpolator based on the Lagrange method for adjusting the variable data rate to a fixed data rate appropriate for each standard. The two proposed configurations are analyzed and compared to provide insight into aliasing and the signal bandwidth by means of a newly introduced measure called interpolation error. The average interpolation error is reduced as the ratio of the sampling frequency to the signal BW is increased. The decimation chain and the multi-rate analog-to-digital converter are simulated to compute the interpolation error and the output signal-to-noise ratio. Further, a method to operate the above-mentioned chain under a compressed mode of operation is proposed in order to guarantee continuous packet connectivity for inter-radio-access technologies. The presented decimation chain can be applied to LTE, WCDMA, GSM multi-mode multi-band digital front-end which will ultimately lead to the software-defined radio.