• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.3
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• pp.21-30
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• 1990

This paper describes a hardware implementation of the interframe monochrome video CODEC using a MC-CVQ(Motion Compensated and Classified Vector Quantization) algorithm. The specifications of this CODEC are (1) the resolution of image is $128{\times}128$ pixels, and (2) the transmission rates are about 10frames/sec at the 64Kbps channel. In order to design the CODEC under these conditions, it is implemented by a multiprocessor system composed of MC unit, CVQ nuit and decoder unit, which are controlled by microprogramming technique. And the 3~stage pipelined ALU(Arithmetic and Logic Unit) is adopted to calculate the minimum error distance in the MC unit and CVQ nuit. The realized system shows that the transmission rates are 6-15 frames/sec according to the relative motion of the video signal.

• The Transactions of the Korean Institute of Power Electronics
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• v.5 no.4
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• pp.309-317
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• 2000

This paper presents the switching angle and voltage to maximize torque/efficiency and minimize torque ripple in the 4-phase 6-poles Switched Reluctance Motor(SRM). SRM drive has high saturation and nonlinear characteristics of inductance. So we cannot hard to find optimal condition by using analytic method. Therefore it is hard to find the operating the switching angle and voltage through the approximated analysis and computer simulation by using SIMULINK according to the speed and torque required by load. From the results, we can say that the optimum average voltage is determined by the load only and the speed is determined by the optimum turn-on/off angle only. And the maximum efficiency and minimum torque ripple depend on switching angle, not on voltage. And then one-chip microcontroller controls the switching angle and voltage of an asymmetrical inverter in the SRM driver. This drive method, which is expect that the driving methods, which are maximizing torque/efficiency and minimizing torque ripple, will be suitable for the electric vehicle, the industrial application and household appliances.

• Science of Emotion and Sensibility
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• v.7 no.4
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• pp.35-41
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• 2004

This study addressed the development of an automobile aroma blast device to reduce fatigue of drivers. We also analyzed the adaptation character of the aroma blast device, The aroma blast device was designed in a way that volatilized aroma is mixed with oxygen (air) and blasted to the outside, It was devised to possibly change on/off time of 2-Port Solenoid Valve using the 8051 micro processor, through which the amount of aroma can be controlled, We conducted an experiment to examine time for occurrence/elimination of adaptation to aroma in 20 college students using 4 types of natural fragrances, The subjects had an average age of 22$\pm$2 years and included both men and women. The results showed that the occurrence and elimination times for adaptation to aroma were 1 minute 28 seconds and 3 minutes and 15 seconds for Jasmine 30%, 2 minutes and 41 seconds and 4 minutes and 3 seconds for Jasmine 50%, 1 minute and 47 seconds and 2 minutes and 59 seconds for Peppermint 30%, and 1 minute 59 seconds and 4 minutes and 11 seconds for Peppermint 50%, respectively.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.47 no.6
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• pp.6-11
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• 2010

Amount of power generated from solar photovoltaic can vary according to solar flux of sunlight due to nature of solar cell panel, and an angle that the sun and the surface of cell makes brings difference in amount of power generation. Solar flux is decided by location of surface of the Earth that is classified into longitude and latitude, but on the other hand, an angle that the sung and the surface of cell makes can be changed by changing the angle of a solar power generation device at the fixed location. A method of changing the angle of a solar power generation device as a measure for improving practical power generation efficiency. and studies about a solar tracking device for this are in active. This study conducted a research on a solar tracking system for improvement of solar power generation efficiency. A solar tracking system of this study is composed of a sensor part to confirm a location of the sun with a semiconductor photosensor using the photo conductive effect, and it analyzed output signal of a sensor by using microprocessor and it produced a control signal of driving part for tracking the sun. A solar power generator (25W) was produced to analyze performance of a solar tracking system and usefulness of a solar tracking device that was designed and produced in this study was confirmed through experiments.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.2
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• pp.129-135
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• 1999

The telemetry system for the current speed and direction, the underwater ambient noise and the distribution ecology of fishes was constructed by the author and his collaborator in order to product and manage effectively in shallow sea culture and setnets fisheries, and then the experiments for the telemetry system carried out at set net fishing ground located Nungpobay in Kojedo from October 1996 to June 1997. As this results, the techniques suggested in the telemetry system gave full display its function even though far away 1.5 km from transmitting part, but with the suggested telemetry system could not be ascertained relationship between physical environment and distribution ecology of fishes.

• Journal of the Korean Society for Railway
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• v.19 no.1
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• pp.38-45
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• 2016

The power transformation system of High Speed rolling stocks like KTX-Sancheon has shown excellent control capacities in the areas of riding comfortability, switching efficiency, safety and energy consumption due to technical developments in power-electronics, high speed & large scale integrated semiconductors and microprocessors. However, harmonics from IGBT, a high speed switching device used in the Convertor & Invertor equipment of rolling stocks have given rise to various problems in transformer substations, signaling systems, data transmission systems and facility monitoring systems. Especially, TI21 non-insulated track circuits have malfunctioned due to the influence of returning current harmonics which were generated at around of integer times of the number of power transformation equipment in the frequency domain. This paper, measures and analyzes various schemes to analyze the traveling path of the returning current harmonics generated due to the relationship between the rolling stocks and track circuits on site. Ultimately, theseschemes will be used to design high speed rolling stocks, AF track circuits and a common grounding network.

• Journal of Korean Society of Forest Science
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• v.89 no.3
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• pp.405-413
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• 2000

This study was conducted to develop an on-line monitoring system for a forest hydrological environment and its meteorological condition, such as temperature, wind direction and speed, rainfall and water level on V-notch, electrical conductivity(EC), potential of hydrogen(PH) by the motor drive sensor unit and measurement with a single-chip microprocessor as controller. These results are summarized as follows ; 1. The monitoring system consists of a signal process unit, motor drive sensor unit, radio modem unit and power supply. 2. The motor drive sensor unit protects the sensor from swift current or freezing and can constantly maintain fixed water level during measurements. 3. This monitoring system can transfer the data by radio modem. Additionally, this system can monitor hydrological conditions in real time. 4. The hardware was made of several modules with an independent CPU. They can be mounted, removed, repaired and added to. Their function can be changed and expanded. 5. These are the result of an accuracy test, the values of temperature, EC and pH measured within an error range of ${\pm}0.2^{\circ}C$, ${\pm}1{\mu}S$ and ${\pm}0.1pH$ respectively. 6. This monitoring system proved to be able to measure various factors for a forest hydrological environment in various experimental stations.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.6
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• pp.43-52
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• 2018

Livestock production is the second largest economic activity of Pakistan's rural population, more specifically; sixty-seven percent of Pakistan's total population that live in rural areas sources their income from livestock activities. As this subsector of agriculture within rural Pakistan is so critical to Pakistan's economy it is especially important to further develop the sector through the introduction of cost effective, efficient, and practical technologies. In an effort to improve such an important sector within the agriculture sector in Pakistan research has been carried out to better understand the capabilities and feasibility of leveraging Internet of Things based technologies, such as, microprocessors and microcontrollers within Pakistan's livestock production and management. The internet of Things can potentially allow for the scaling of small-scale rural livestock production to larger operations through cost effective and efficient livestock management through the application of IoT technologies. This paper discusses the architecture models of IoT based smart animal farms and delves into the pitfalls and advantages of applying IoT technologies in this sector. In this work we will explore the cheap sensors to monitor the internal activities of cattle farm with the aim of using these sensors as part of system to detect the important operations that need on the time response. This system should provide the feed and water as required, and control the temperature in sheds to protect the cattle being ill and on heat, and humidity level .internet connection used to connect these devices with smartphones or computers. In this paper we proposed the architecture model of IoT based smart animal farm.

• Journal of Practical Engineering Education
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• v.14 no.1
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• pp.1-10
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• 2022

Learning C programming language in electronics education is an important basic education course for understanding computer programming and acquiring the ability to use microprocessors in embedded systems. In order to focus on understanding basic grammar and algorithms, it is a common teaching method to write programs based on C standard library functions in the console window and learn theory and practice in parallel. However, if a student wants to start a project activity or go to a deeper stage after acquiring some basic knowledge of the C language, using only the C standard library function in the console window limits what a student can express or control with the C program. For the purpose of making it easier for a student to use graphics or multimedia resources and increase educational value, this paper studies a case of applying Simple DirectMedia Layer (SDL), an open source software, into the C programming language learning process. The SDL-based programming course applied after completing the basic programming curriculum performed in the console window is introduced, and the educational value is evaluated through a survey. As a result, more than 56% of the respondents expressed positive opinions in terms of improved application ability, stimulating interest, and overall usefulness, and less than 4% of them had negative opinions.