• Analytical Science and Technology
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• v.10 no.5
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• pp.332-342
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• 1997

Fifteen volatile organic pollutants were spiked in blank water at the concentration of $20{\mu}g/L$ and analyzed with Purge and Trap and GC/MS. As a result, the overall mean recovery of 100% was obtained with a mean relative standard deviation of 3.6%. The method detection limits were in the range of $1.9{\sim}3.3{\mu}g/L$. In the wastewater analysis of Banwol dyeing comlex, 15 organic compounds were identified and three of these were quantified. Among the compounds identified, only trichloroethylene and tetrachloroethylene are regulated in wastewater by the Korea Ministry of Environment. But, the concentration of these two compounds were below the government allowance level.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.11
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• pp.1562-1569
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• 2018

Sensor readings always have a certain degree of randomness and fuzziness due to its intrinsic property, other electronic devices in the circuitry, wires and the rapidly changing environment. In an electrical control system, such readings will bring instability in the system and other undesired events especially if the signal hovers around the threshold. This paper proposes a Gaussian-based statistical approach in stabilizing the output through sampling the sensor data and automatic tuning the threshold to the range of multiple standard deviations. It takes advantage of the Central limit theorem and its properties assuming that a large number of sensor data samples will eventually converge to a Gaussian distribution. Experimental results demonstrate the effectiveness of the proposed algorithm in completely stabilizing the outputs over known filtering algorithms like Exponential smoothing and Kalman Filter.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.11
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• pp.5527-5545
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• 2019

Through-wall ultra-wide band (UWB) radar has been considered as one of the preferred and non-contact technologies for the targets detection owing to the better time resolution and stronger penetration. The high time resolution is a result of a larger of bandwidth of the employed UWB pulses from the radar system, which is a useful tool to separate multiple targets in complex environment. The article emphasised on human subject localization and detection. Human subject usually can be detected via extracting the weak respiratory signals of human subjects remotely. Meanwhile, the range between the detection object and radar is also acquired from the 2D range-frequency matrix. However, it is a challenging task to extract human respiratory signals owing to the low signal to clutter ratio. To improve the feasibility of human respiratory signals detection, a new method is developed via analysing the standard deviation based kurtosis of the collected pulses, which are modulated by human respiratory movements in slow time. The range between radar and the detection target is estimated using joint time-frequency analysis (JTFA) of the analysed characteristics, which provides a novel preliminary signature for life detection. The breathing rates are obtained using the proposed accumulation method in time and frequency domain, respectively. The proposed method is validated and proved numerically and experimentally.

• Korean Journal of Human Ecology
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• v.15 no.1
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• pp.177-185
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• 2006

The purpose of this study is to research middle school students' interests in the housing education contents of Technology Home Economics Subject - to classify the contents into three units, we have application of living space, indoor environment and equipments, support and repair of housing. This study has a subject of 529 middle schoolers living in Jeonbuk province. In this statistical analysis, SPSS program was utilized to analyze percentage, mean and standard deviation. These materials were also verified by t-test. The results of this research were as follows: Middle school students' interests in housing education contents stayed at a mid-level. There was a significant difference in contents interest according to their gender - boys appeared to have a higher interest than girls. On the basis of these results, it can be suggested that these results offer fundamental information for improving students' critical practice in their real life. Since this study has conducted a limited research with a topic of housing education only, it is essential that further research covering a wider array of themes be done in the future.

• International Journal of Automotive Technology
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• v.7 no.5
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• pp.603-608
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• 2006

As an important and relatively easy to implement technology for realizing Intelligent Transportation Systems(ITS), Adaptive Cruise Control(ACC) automatically adjusts vehicle speed and distance to a preceding vehicle, thus enhancing driver comfort and safety. One of the key issues associated with ACC development is usability and user acceptance. Control parameters in ACC should be optimized in such a way that the system does not conflict with driving behavior of the driver and further that the driver feels comfortable with ACC. A driving simulator is a comprehensive research tool that can be applied to various human factor studies and vehicle system development in a safe and controlled environment. This study investigated driving behavior with ACC for drivers with different driving styles using the driving simulator. The ACC simulation system was implemented on the simulator and its performance was evaluated first. The Driving Style Questionnaire(DSQ) was used to classify the driving styles of the drivers in the simulator experiment. The experiment results show that, when driving with ACC, preferred headway-time was 1.5 seconds regardless of the driving styles, implying consistency in driving speed and safe distance. However, the lane keeping ability reduced, showing the larger deviation in vehicle lateral position and larger head and eye movement. It is suggested that integration of ACC and lateral control can enhance driver safety and comfort even further.

• Journal of Korea Multimedia Society
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• v.3 no.5
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• pp.506-515
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• 2000

In this paper a web-based real-time education system, which is able to support education through multimedia, is suggested for the expansion of learner's creative ability in the school. This system is designed so that it can support three things: 1) a real time interaction between interaction between instructors and learners, 2) individual learning through such an interaction, and 3) a coercive distribution of display by instructions for preventing the deviation of learners from learning. Also, the system, which UML is applied to, makers efficient interaction possible through the module for the real-time exchange and management of messages even in the multi-user environment. Through this system, not only the simulation by learners can be made for experiments and practices, but also questions and respondence can be supported on the procedure of experiments and the analysis of their results. This system is bulit on constructivism, and aimed at helping the learning progress and knowledge formation of learners.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.30-38
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• 2017

The red-spotted apollo butterfly, Parnassius bremeri Bremer, 1864 (Lepidoptera: Papilionidae), is an endangered species in South Korea. Development and application of molecular markers to assess population genetics perspectives can be used as a basis to establish effective conservation strategies. In this study, we developed 12 microsatellite markers specific to P. bremeri using Illumina paired-end sequencing and applied the markers to South Korean populations to understand population characteristics. Genotyping of 40 P. bremeri individuals from three localities showed that at each locus, the observed number of alleles ranged from 6 to 22 and the observed and expected heterozygosities were 0.500-1.00 and 0.465 to 0.851, respectively. Significant deviation from the Hardy-Weinberg equilibrium was not observed in all loci studied. The population based $F_{ST}$ and $R_{ST}$ collectively suggest that at least the Samcheok population in northernmost Gangwon Province has a significant divergence from the remaining two populations (P < 0.01), and this result is also reflected in the forewing length. Further studies with an increased sample size will be necessary to draw robust conclusions and devise conservation strategies.

• Journal of Korean Academy of Nursing Administration
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• v.9 no.1
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• pp.31-40
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• 2003

Purposes : The purpose of this study is to analyze the correlation among Expectations, Performance-Perception, Willingness of reuse of hospital. Methods : The subjects of this study were 120 patients who were admitted in the hospitals over 1 week in Pusan. The data was collected by self-reporting questionnaires from Oct. 16th, to Nov. 5th, 2001. The data were analysed by SPSS/PC package using frequency, percentage, mean, standard deviation, Pearson's correlation coefficient. Results : The results were as follows; 1) The mean score of Expectation was 3 and over. The highest item was 'equal treatment' and the lowest was 'safety in transaction'. 2) The mean score of Performance-Perception was 4 and under. The highest item was 'nurse' attractive appearance' and the lowest was 'equal treatment', 'kindness and etiquette'. 3) The mean score of Willingness of reuse was 3.11. 4) There was a statistical significance of the difference between Expectations and Performance-Perception. The highest difference item was 'equal treatment', and then the lowest difference item was 'working environment arrangement/order'. 5) There were statistically significant positive correlation among Expectations, Performance-Perception, and Willingness of reuse. The highest correlation was 0.89 between Performance-Perception and Willingness of reuse. Conclusions : Nursing managers have to develop nurse training programs for improving of patient's performance perception on nursing service.

• Journal of Environmental Science International
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• v.26 no.5
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• pp.661-674
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• 2017

This study used questionnaires to investigate how pre-service elementary teachers understand ocean acidification. As a result of gender, female teachers were more aware of ocean acidification than male teachers, but male teachers had a higher average rate of correct answers, with a lower standard deviation. Teachers from the natural sciences knew more about ocean acidification than did teachers the liberal arts. Teachers ranked environmental crisis in order of most dangerous to least dangerous as follow: global warming and the greenhouse effect, ozone depletion, ocean acidification, and acid rain. About 46.7% of teachers learn about ocean acidification through education, followed by broadcasts, school lectures and the internet. The educational materials most desired for teachers were videos related to ocean acidification. Pre-service elementary teachers have two broad perspectives on ocean acidification. Firstly, they refer to economic loss and food shortages, and secondly, they note that there is a need for improved awareness and publicity about ocean acidification. The role of elementary school teachers is important because their awareness of environmental issues has a considerable effect on teachers perception of the environment. Revitalizing education on ocean acidification and government support are necessary to effectively communicate the seriousness of ocean acidification. Lastly, we need to study ocean acidification in detail so as to be able to persevere toward protecting our ocean ecosystem.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.5 s.176
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• pp.1343-1351
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• 2000

Thermally induced errors have been significant factors affecting the machine tool accuracy. In this paper, the spindle thermal error has been focused, where the 5 degree of freedom thermal error components are considered. An effective measurement system has been devised for the 5 DOF thermal errors, consisting of gap sensors and thermocouples around the micro-computer interfaced environment. Several thermal error modeling techniques are also implemented for the thermal error prediction: multiple linear regression, neural network and system identification methods, etc. The performance of the thermal error modeling techniques is evaluated and compared, giving the system identification method as the optimum model having the least deviation. The developed system for the thermal error measurement and modeling was practically applied to a CNC machining center, and the spindle thermal errors were effectively compensated around the micro computer-machine tool interfaced networks. The machine tool accuracy was improved about 4-5 times typically.