• The KIPS Transactions:PartB
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• v.10B no.6
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• pp.695-704
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• 2003

This paper proposes a new scheduling technique to play multimedia data streams in mobile terminals. The paper explores the characteristics of multimedia data streams , firstly. On basis of these characteristics, selection of specific data stream can be possible as well as transcoding protest. Our approach aims at reducing the early-stage delay time more effectively since it makes possible to select and transcodes some specific streams by employing a selection policy rather than transcoding all streams in the playing process Thus, this paper suggests a stream selection policy for the transcoding based on EPOB (End Point of Over Bandwidth). It aims to lower the required bandwidth of multimedia streams than the network bandwidth level and also to minimize early-stage delay time for multimedia streams, which is to be played in mobile terminals.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.6
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• pp.1401-1406
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• 2014

Knowledge of the manufacturing process of semiconductor devices in order to obtain a copper pattern using chemical mechanical polishing (CMP) planarization using a Wafer polishing process is applied with a thickness of the copper measured in real time, which need to be precisely controlled by, where the acquisition the actual thickness of the sensor value with the calculated value in terms of error can occur in the process. Approximated the actual measurement values so as to obtain a method using a simple average, moving average, compared to the results using filters onggo Strom real-time measurements of the thickness of the units of the control system to reduce the variation in the implementation of the method described for the.

• Transactions on Electrical and Electronic Materials
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• v.2 no.3
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• pp.24-27
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• 2001

The end point of oxide chemical mechanical polishing (CMP) have determined by polishing time calculated from removal rate and target thickness of oxide. This study is about control of oxide removal amounts on the shallow trench isolation (STI) patterned wafers using removal rate and thickness of blanket (non-patterned) wafers. At first, it was investigated the removal properties of PETEOS blanket wafers, and then it was compared with the removal properties and the planarization (step height) as a function of polishing time of the specific STI patterned wafers. We found that there is a relationship between the oxide removal amounts of blanket and patterned wafers. We analyzed this relationship, and the post CMP thickness of patterned wafers could be controlled by removal rate and removal target thickness of blanket wafers. As the result of correlation analysis, we confirmed that there was the strong correlation between patterned and blanket wafer (correlation factor: 0.7109). So, we could confirm the repeatability as applying for STI CMP process from the obtained linear formula. As the result of repeatability test, the differences of calculated polishing time and actual polishing time was about 3.48 seconds. If this time is converted into the thickness, then it is from 104 $\AA$ to 167 $\AA$. It is possible to be ignored because process margin is about 1800 $\AA$.

• Journal of Auto-vehicle Safety Association
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• v.5 no.1
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• pp.56-61
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• 2013

This paper presents a development of the Advanced Emergency Braking (AEB) Algorithm for passenger vehicles. The AEB is the system to slow the vehicle and mitigate the severity of an impact when a rear end collision probability is increased. To mitigate a rear end collision, the AEB comprises of a millimeter wave radar sensor, CCD camera and vehicle parameters of which are processed to judge the likelihood of a collision occurring. The main controller of the AEB algorithm is composed of the two control stage: upper and lower level controller. By using the collected obstacle information, the upper level controller of the main controller decides the control mode based not only on parametric division, but also on physical collision capability. The lower level controller determines warning level and braking level to maintain the longitudinal safety. To decide the braking level, Last Ponit To Brake and Steer (LPTB/LPTS) are compared with current driving statues. To demonstrate the control performance of the proposed AEBS algorithm's, closed-loop simulation of the AEBS was conducted by using the Matlab simlink and CarSim software.

• Journal of the Korean Chemical Society
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• v.14 no.4
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• pp.341-345
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• 1970

An improved derivative thermometric titration apparatus designed around operational amplifiers is described which is capable of monitoring the small temperature change and of computing the derivatives for accentuation of the titration end point that is difficult to locate by extrapolation methods. The instrument is constructed of four commercial operational amplifiers. A use of dummy cell provides the subtraction means for compensation of the initial temperature and random temperature fluctuations with a resultant gain in signal-to-noise ratio. The successive differentiation action of the computer has been nearly "perfect," so that the two breaks (blank or starting and end point of the titration curve can be located with the precision of 0.2% by observing two peak points on the second derivative curve. Arrangements useful in obtaining such a good derivative response that is exactly proportional to the input signal are discussed. Plots of the enthalphogram and its derivatives are presented, with the results of several titrations used to evaluate the performance of the apparatus.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.90-93
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• 2000

In this study, the rise throughput and the stability in fabrication of device can be obtained by applying of CMP process to STI structure in 0.18um semiconductor device. To employ in STI CMP, the reverse moat process has been added thus the process became complex and the defects were seriously increased. Removal rates of each thin films in STI CMP was not equal hence the devices must to be effected, that is, the damage was occured in the device dimension in the case of excessive CMP process and the nitride film was remained on the device dimension in the case of insufficient CMP process than these defects affect the device characteristics. To resolve these problems, the development of slurry for CMP with high removal rate and high selectivity between each thin films was studied then it can be prevent the reasons of many defects by reasons of many defects by simplification of process that directly apply CMP process to STI structure without the reverse moat pattern process.

• Journal of the Korea Safety Management & Science
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• v.17 no.3
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• pp.355-362
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• 2015

There has been an increase of using Bosch Process to fabricate MEMS Device, TSV, Power chip for straight etching profile. Essentially, the interest of TSV technology is rapidly floated, accordingly the demand of Bosch Process is able to hold the prominent position for straight etching of Si or another wafers. Recently, the process to prevent under etching or over etching using EPD equipment is widely used for improvement of mechanical, electrical properties of devices. As an EPD device, the OES is widely used to find accurate end point of etching. However, it is difficult to maintain the light source from view port of chamber because of contamination caused by ion conflict and byproducts in the chamber. In this study, we adapted the SPOES to avoid lose of signal and detect less open ratio under 1 %. We use 12inch Si wafer and execute the through etching 500um of thickness. Furthermore, to get the clear EPD data, we developed an algorithm to only receive the etching part without deposition part. The results showed possible to find End Point of under 1 % of open ratio etching process.

• Advances in concrete construction
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• v.11 no.3
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• pp.261-270
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• 2021

In this study, a new understanding is presented on the microcracking behavior of high strength concrete (HSC) with steel fiber addition having prior compressive loading history. Microcracking behavior at critical stress (σcr) region, using seven fiber addition volume of 0.5, 0.75, 1.0, 1.25, 1.5, 1.75, and 2.0% was evaluated, at two aspect ratios (60 and 75). The specimens were loaded up to a specified compressive stress levels (0.70fc-0.96fc), and subsequently subjected to split tensile tests. This was followed by microscopic analyses afterwards. Four compressive stress levels as percentage of fc were selected according to the linearity end point based on stress-time (σ-t) diagram under uniaxial compression. It was seen that pre-compression has an effect on the linearity end point as well as fiber addition where it lies within 85-91% of fc. Tensile strength gain was observed in some cases with respect to the 'maiden' tensile strength as oppose to tensile strength loss due to the fiber addition with teething effect. Aggregate cracking was the dominant failure mode instead of bond cracks due to improved matrix quality. The presence of the steel fiber improved the extensive failure pattern of cracks where it changes from 'macrocracks' to a branched network of microcracks especially at higher fiber dosages. The applied pre-compression resulted in hardening effect, but the cracking process is similar to that in concrete without fiber addition.

• Journal of Engineering Education Research
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• v.25 no.4
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• pp.35-41
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• 2022

In order to enhance basic competencies for freshmen at engineering college, whose learning ability is gradually declining, a new course was developed to review basic mathematics and physics through a process of collecting opinions from fellow professors. Tests in six fields of math and physics with the same problems showed the correct answer rate rose from 24.8% at the beginning of the semester to 59.0% at the end of the semester after operating the course developed. According to the survey, the students' self-evaluated confidence on the basic competencies in 16 fields of math and physics showed a significant increase. Students with high confidence in basic competencies also received high actual grades. General high school graduates' confidence point in basic competencies improved from 54.7 at the beginning to 75.3 points at the end of the semester, while specialized high school graduates' enhanced from 38.3 to 64.0 which is higher than that of general high school graduates at the beginning of the semester.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.651-663
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• 2006

Hazard Analysis and Critical Control Point (HACCP), a systematic process that identifies, assesses, and controls hazards, has been developed as an effective alternative to conventional end-point analysis for food safety control. The importance of HACCP has been emphasized recently due to the development of new food processing technologies and the increase in international trade demanding worldwide of food product safety. This paper provides a review of HACCP and a generic HACCP template for its implementation for aseptic processing of a juice drink.