• Journal of Satellite, Information and Communications
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• v.11 no.3
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• pp.65-71
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• 2016

Currently developing the OBC of the next-generation LEO satellite by Korea Aerospace Research Institute adopts the LEON2-FT/AT697F processor to achieve high performance. And various communication devices such as SpaceWire, MIL-STD-1553B, DMAUART and CAN Master are integrated to the separated standard communication FPGAs within the OBC, where they can be controlled by the processor and flight software (FSW) through PCI interface. The Actel 1553BRM IP core is used for the 1553B in the next-generation LEO OBC and the B1553BRM wrapper from Aeroflex Gaisler is used for connecting it to the AMBA bus in FPGA. This paper presents the design and development of PCI-based 1553B communication software, and describes the handling mechanism of 1553B operation in FSW task level. Also it shows the test results on real-hardware and simulator.

• Journal of Satellite, Information and Communications
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• v.8 no.1
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• pp.54-60
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• 2013

The need for high performance of on-board computer (OBC) is essential due to the growing requirements and diversified missions, and so OBC has been developed on the basis of the standard design and reconfigurable modularization in order to improve the utilization of OBC for different missions. The processor in OBC of next generation satellite which is currently developed by KARI is adopted the LEON2-FT/AT697F processor based SPARC v8 as main processor and controls various devices such as SpaceWire, MIL-STD-1553B and CAN through PCI on the standardized communication chips. This paper presents the architecture and design of system software for LEON2-FT processor based on PCI, and development of PCI software component. Also it describes the porting of VxWorks 6.5 for LEON2-FT and the test under the simulation environment for LEON2-FT and PCI with communication chips.

• Journal of the Korean Society of Safety
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• v.25 no.2
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• pp.29-34
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• 2010

This paper is aimed to develop monitoring software for detecting the characteristics of current and voltage signals for series arc on electric wire. In order to attain this purpose, the characteristics of series arc were analyzed by the current and voltage signals on electric wire which were installed, and also analyzed by the changes of RMS, instantaneous of waveform value in time domain and THD in frequency domain. Monitoring program which analyze the signal was developed by Labview which can analyze in time domain and frequency domain, and save data. Experimental setup for detecting verification of monitoring program was composed loads of a lamp, an electric heater and an electric fan loads which were usually using. Measurement points for detecting verification of monitoring program were selected at both the panel board and the arc generator at the same time. As results of the experiments by monitoring program, the arc current waveform showed the same characteristic in all measurement points of all load. But the arc voltage waveform was different in each measurement point. When arc occurred, the THD of current value increased above 20%. The results of this study will be effectively used in developing the preventive system of electric fire by series arc.

• Journal of the Korea Safety Management & Science
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• v.26 no.1
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• pp.31-38
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• 2024

In this paper, as there are many cases of fires occurring due to the failure or inoperability of the thermostat of electronic products, the purpose is to test and analyze the risks and probabilities through fire cases and reproduction experiments, and suggest countermeasures. Among electronic products, water purifiers are composed of a refrigerant system with a compressor to make cold water, a heating device to make hot water, and an electric device used as an energy source. Due to the nature of the water purifier manufacturing, these devices are subject to a lot of moisture and dust. etc. exist in large quantities and use electrical energy, so there is a possibility of fire due to short circuit in the wire, electrical abnormal overheating (tracking phenomenon) in the thermostat, electronic board, starting relay, etc., and overheating of the heating device (Band Heater). there is. Therefore, in order to prevent fires from these devices, a system to remove foreign substances inside the water purifier is necessary, the use of heat-resistant (fire-resistant) wires for electrical devices is essential, and the use of non-combustible materials (semi-combustible materials) for each part is necessary to prevent fire. The risk must be eliminated through prevention and combustion expansion prevention devices.

• Journal of Biosystems Engineering
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• v.14 no.2
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• pp.128-136
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• 1989

The purpose of this study was to develop a computer operated automatic drip irrigation system for application in vinyl-house cultivation. The results can be summarized as follows: 1) The T-type ice compensation wire was used to measure the temperature. The voltage level measured up to 0.02 volt was used as input to an 8-bit A/D converter. 2) A specially devised tensiometer was used to content the watering system. When the needle of the pressure gauge reaches the lower threshold position it turns on the pumping system and turns off when it reaches higher threshold position. 3) In order to use the multiple gypsum blocks for one transducer, reed relays and a D/O board were used to make the sequential switching possible. 4) It was possible to automate the trickle irrigation system for the whole growth period of vinyl-house crops with the help of microcomputer. 5) In terms of furrow irrigation, the irrigation water consumption was the smallest, 2.8 times less than conventional method of surface trickle irrigation, 3.4 times less than subsurface trickle irrigation method. 6) In terms of productivity of cucumber, there was a drop in productivity when compared to furrow irrigation method, 7.2% for surface trickle irrigation, 27.4% for subsurface irrigation method.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.5
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• pp.159-167
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• 2002

In this paper. we present a new method for monitoring of ECU's self diagnostic signals of vehicle without wire. In order to measure the ECU's self diagnostic signals, the interfaced circuit is designed to communicate ECU and designed terminal according to the IOS, SAE regulation of communication protocol standard. Micro-processor 80C196KC is used for communicating ECU's self diagnositc signals and the results are sent to the wireless terminal and PC monitoring system. Wireless terminal is also developed by 80C196KC, LCD, RF module, and keypad. The command from the keypad is sent to ECU through RF module and the result show on the Graphic LCD in real time. Software on PC is developed to monitor the ECU's self diagnostic signals using the Visual C++ complier in which RS232 port is programmed by half duplex method. The algorithms for measuring the ECU's self diagnostic signals are verified to monitor both ECU and portable terminal state. At the same time, the information to fix the vehicle's problem can be shown on the developed software. The possibility for remote measurement of ECU self diagnostic signal is verified through the developed systems and algorithms.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.279-282
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• 2002

In this paper, we present a new method for monitoring of ECU's self diagnostic signals of vehicle without wire. In order to measure the ECU's self diagnostic signals, the interfaced circuit is designed to communicate ECU and a designed display terminal according to the ISO, SAE regulation of communication protocol standard. A 80C196KC processor is used for communicating ECU's self diagnostic signals and the results are sent to PDA monitoring system. Software on PDA is developed to monitor the ECU's self diagnostic signals using the Embedded Visual C++ compiler in which RS232 port is programmed by half duplex method. The algorithms for measuring the ECU's self diagnostic signals are verified to monitor ECU's state. At the same time, the information to fix the vehicle's problem can be shown on the developed PDA software. The possibility for remote measurement of ECU self diagnostic signal using PDA is also verified through the developed systems and algorithms.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.9
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• pp.825-831
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• 2006

As an increase of chip complexity and level of chip integration, chip input/output (I/O) pad pitches are also drastically reduced. With arrival of high complexity SoC (System on Chip) and SiP (System in Package) products, conventional horizontal type probe card showed its limitation on probing density for wafer level test. To enhance probing density, we proposed new vertical type probe card that has the $70{\mu}m$ probe needle with tungsten wire in $80{\mu}m$ micro-drilled hole in ceramic board. To minimize alignment error, micro-drilling conditions are optimized and epoxy-hardening conditions are also optimized to minimize planarity changes. To apply wafer level test for target devices (T5365 256M SDRAM), designed probe card was characterized by probe needle tension for test, contact resistance measurement, leakage current measurement and the planarity test. Compare to conventional probe card with minimum pitch of $50{\sim}125{\mu}m\;and\;2\;{\Omega}$ of average contact resistance, designed probe card showed only $22{\mu}$ of minimum pitch and $1.5{\Omega}$ of average contact resistance. And also, with the nature of vertical probing style, it showed comparably small contact scratch and it can be applied to bumping type chip test.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.214-214
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• 2009

While critical properties of BSCCO wires rely considerably on grid direction upon BSCCO and have very complicated mechanism of generating a superconducting phase, making it difficult to improve properties of wires, YBCO thin-film wires which can be formed in a superconducting phase upon metal board through vapor deposition processing can get excellent direction and reduce manufacturing costs with more flexibility in improving critical properties; thus, they will be suitable for instrument application in the future. Contrary to BSCCO wires for which thick silver alloy covering materials should inevitably be used, moreover, YBCO thin-film wires have an advantage of making thickness and quality of covering materials different by usage. Such a property can be an important element to widen application of wires by presenting possibility of using thin-film wires as superconducting material for fault current limiter as well as for high power current application. In this study we intend to prepare YBCO thin-film wires with different stabilizer layers to analyze current application and current restriction properties by stabilizer layers on the basis of detailed researches on changes in current classification properties below critical value.

• Journal of Sensor Science and Technology
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• v.30 no.2
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• pp.88-93
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• 2021

In this paper, a folding sensor based on capacitance is proposed. The sensor was developed to sense the length and angle data for the milli-scale actuators without causing any interference to the actuating joints. For the sensing and testing the robotic joint with reducing the cost and complexity aspects of manufacturing, a simple composition was adopted. The sensor comprises a pair of copper tapes, papers, and wires. The complete sensing unit is constructed by bonding the tapes with the papers and soldering the wire to the copper parts. For accuracy, a teensy 4.0 board, which has a 12-bit ADC resolution, is employed. Furthermore, the sensed analog data is not translated into the unit of capacitance for accuracy; however, it is filtered using a low-pass filter and subsequently, a Butter-worth filter. The data obtained demonstrate a periodic waveform, which implies that the data are in good agreement with the hypothesis set prior to the experiments. Compared to other milli-scale sensors, this could be a better option for sensing the length and angle data for milliscale actuators.