• Communications of Mathematical Education
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• v.30 no.1
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• pp.1-22
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• 2016

We had a full scale of literature survey and case survey of mathematics Flipped Learning class models. The purpose of this study is to design and adopt a Flipped Learning 'Linear Algebra' class model that fis our need. We applied our new model to 30 students at S University. Then we analyzed the activities and performance of students in this course. Our Flipped Learning 'Linear Algebra' teaching model is followed in 3 stages : The first stage involved the students viewing an online lecture as homework and participating free question-answer by themselves on Q&A before class, the second stage involved in-class learning which researcher solved the students' Q&A and highlighted the main ideas through the Point-Lecture, the third stage involved the students participating more advanced topic by themselves on Q&A and researcher (or peers) finalizing students' Q&A. According to the survey, the teaching model made a certain contribution not only to increase students' participation and interest, but also to improve their communication skill and self-directed learning skill in all classes and online. We used the Purposive Sampling from the obtained data. For the research's validity and reliability, we used the Content Validity and the Alternate-Form Method. We found several meaningful output from this analysis.

• The Journal of Korean Physical Therapy
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• v.18 no.2
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• pp.25-34
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• 2006

Purpose: This study conducted quantitative sensory test and nociceptive flexion reflex(NFR) measurement to examine degree of pain depending on polarity of high voltage pulsed current(HVPC) of hyperalgesia site in hyperalgesia rat by local thermal injury. mechanical pain threshold, thermal pain threshold and root mean square of NFR were measured. Methods: This study was conducted with control group I of hyperalgesia rat at hind paw by thermal injury and experimental groups divided into cathodal HVPC group II, anodal HVPC group III and alternate HVPC group IV. It measured pain threshold and root mean square(RMS) of NFR and obtained the following results. Results: Mechanical pain threshold of hyperalgeisa site was significantly increased at groups II, III and IV applying HVPC group compared to control group, but there was no difference among HVPC groups. Thermal pain threshold of hyperalgesia site showed a significant increase in group II. Group III showed significant difference after 4 days of hyperalgesia. RMS of NFR at hyperalgeisa site was significantly reduced in group II after 2 days of hyperalgesia. Group III showed significant decrease after 5 and 6 days of hyperalgesia. Conclusion: Consequently it was found that application of HVPC of hyperalgesia site increased pain threshold at hyperalgesia site by mechanical stimuli and thermal stimuli. NFR by electrical stimuli was similar to pain threshold by mechanical stimuli. Effects by polarity of HVPC showed the greatest reduction of hyperalgesia when cathodal electrode was used.

• Proceedings of the KSRS Conference
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• 2005.10a
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• pp.717-720
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• 2005

Recently as large sized urban development and the city ward drifting of population are caused, the urban surface temperature is raised very seriously and rapidly. These artificial developments have destroyed the inner and outer landscapes such as topography and have changed complex local climate such as a sudden rise in temperature, the change of wind field and air pollution. In order to clarify this problem visually, the studies on extracting the thermal infrared and the characteristic analysis of local climate in urban area had been performed by using the sixth band of Landsat TM and ETM+. However, there is a need to alternate Landsat TM and ETM+ because these satellite images are not applied any more. Therefore, in this paper it is proposed to use 2 Aster image (2004.4.17 daily 2b03, 2004.10.10 night 2b03) of EOS AM and to extract the surface temperature. Also, the pattern of surface temperature in urban area and the application possibility in local climate study are proposed by verifying the correlation with A WS data. Also, IKONOS image was used to figure out the artificial development area in visual.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.3
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• pp.523-534
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• 1994

The purpose of this study is to develop computer simulation model that produce precipitation patterns from stochastic model. In the paper(I) of this study, the alternate renewal process(ARP) is used for the daily precipitation series. In this paper(Il), stochastic simulation models for the daily precipitation series are developed by combining Markov chain for the precipitation occurrence process and continuous probability distribution for the precipitation amounts on the wet days. The precipitation occurrence is determined by first order Markov chain with two states(dry and wet). The amounts of precipitation, given that precipitation has occurred, are described by a Gamma, Pearson Type-III, Extremal Type-III, and 3 parameter Weibull distribution. Since the daily precipitation series shows seasonal variation, models are identified for each month of the year separately. To illustrate the application of the simulation models, daily precipitation data were taken from records at the seven locations of the Nakdong and Seomjin river basin. Simulated data were similar to actual data in terms of distribution for wet and dry spells, seasonal variability, and precipitation amounts.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.138-138
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• 2009

Recently, thin-film solar cells of Cu(In,Ga)$Se_2$(CIGS) have reached a high level of performance, which has resulted in a 19.9%-efficient device. These conventional devices were typically fabricated using chemical bath deposited CdS buffer layer between the CIGS absorber layer and ZnO window layer. However, the short wavelength response of CIGS solar cell is limited by narrow CdS band gap of about 2.42 eV. Taking into consideration the environmental aspect, the toxic Cd element should be replaced by a different material. It is why during last decades many efforts have been provided to achieve high efficiency Cd-free CIGS solar cells. In order to alternate CdS buffer layer, ZnS buffer layer is grown by using chemical bath deposition(CBD) technique. The thickness and chemical composition of ZnS buffer layer can be conveniently by varying the CBD processing parameters. The processing parameters were optimized to match band gap of ZnS films to the solar spectrum and exclude the creation of morphology defects. Optimized ZnS buffer layer showed higher optical transmittance than conventional thick-CdS buffer layer at the short wavelength below ~520 nm. Then, chemically deposited ZnS buffer layer was applied to CIGS solar cell as a alternative for the standard CdS/CIGS device configuration. This CIGS solar cells were characterized by current-voltage and quantum efficiency measurement.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.36-40
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• 2004

It is now widely accepted that immobilized microbial cells can overcome some of the problems associated with microbial survival stability, efficacy, storage, transportation and ease of application in agricultural environments. Pantoea agglomerans, a phosphate solubilizing bacterium, was immobilized in alginate, agar and gelatin carriers. All the three immobilfized carriers with bacterial cells of P. agglomerans were compared for solubilization of tricalcium phosphate in pure liquid cultures. While alginate beads were tested for phosphate solubilization on alternate days up to five days, agar beads and gelatin cubes were subjected for one time phosphate solubilization analysis after seven days. Both alginate and agar immobilized cells of P. agglomerans exhibited higher efficiency in increasing the solubilizaliun of tricalcium phosphate than gelatin immobilized cells. The culture filtrate of alginate bead inoculation treatment registered a rapid increase in soluble phosphate concentration upon incubation. A corresponding decrease in the pH of the medium was also observed in all the treatments.

• Journal of Yeungnam Medical Science
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• v.4 no.1
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• pp.1-15
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• 1987

Magnetic Resonance (M.R.) is rapidly emerging technique that provides high quality images and potentially provides much more diagnostic information than do conventional imaging modalities. M.R.I. is conceptually quite different from currently used imaging methods. The complex nature of M.R.I. allows a great deal of flexibility in image product ion and available information, and key points are as follows. 1. M.R.I. offers a non-invasive technique with which to gene rate in vivo human images without ionizing radiation and with no known adverse biological effects. 2. Imaging mechanism of M.R.I. is quite different from conventional imaging modality and for more accurate diagnostic application, It is necessary for physician to understand imaging mechanism of M.R.I. 3. M.R. makes available basic chemical parameters that may provide to be useful for diagnostic medical imaging and more specific pathophysiologic information which are not available by alternate techniques. 4. M.R. can be produced by number of different methods. This flexibility allows the imaging technique to be applicated for particular clinical purpose. Multiplanar and three dimensional imaging may extend the imaging process beyond the single section available with current CT. 5. Future directions include efforts to; a. Further development of hard ware b. More fasternning scan time c. Respiratory and cardiac gated imaging d. Imaging of additional nuclei except hydrogen e. Further development of contrast media f. M.R. in vivo spectroscopy g. Real time M.R. imaging.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.4 no.1
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• pp.1-12
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• 2006

This study conducted RIII reflex measurement to examine degree of pain depending on polarity of high voltage pulsed current of primary and secondary hyperalgesia site in hyperalgesia rat by local thermal injury. Hind paw which was injury site was taken as primary hyperalgeisa site, sole which was injury adjacent site was taken as secondary hyperalgesia site, and mechanical pain threshold, thermal pain threshold and root mean square of RIII reflex were measured. This study was conducted with control group I of hyperalgesia rat at hind paw by thermal injury and experimental groups divided into cathodal high voltage treatment group II, anodal high voltage treatment group III and alternate high voltage treatment group IV, applied active electrode of high voltage pulsed current to hind paw directly, placed reference electrode on the sole of injury adjacent site and applied pulse frequency. It measured RIII reflex and obtained the following results: Root mean square of RIII reflex at primary hyperalgeisa site was significantly reduced in group II after 2 days of hyperalgesia. Group II showed significant decrease after 5 and 6 days of hyperalgesia. Root mean square of RIII reflex at secondary hyperalgesia site showed significant reduction in group II after 6 days of hyperalgesia. Consequently it was found that application of high voltage pulsed current of hyperalgesia site reduced RIII reflex at primary hyperalgeisa site and secondary hyperalgesia site by electrical stimuli. Effects by polarity of high voltage pulsed current showed the greatest reduction of pain threshold when cathodal active electrode was used.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.1316-1323
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• 2005

Most tunnel lining material which has been used in the domestic is a concrete. But many problems as the construction period, the cost, and the crack occurrence for the design, construction, and management were happened in the concrete lining. For this reason, many research institutes like the Korea Highway Corporation recognize the necessity of an alternate material development and grow on the interest for that. So in this study, the behaviour characteristics for the application of the Corrugated Steel Plate Lining in cut-and-cover tunnel are evaluated as several conditions for the backfill height, the cutting slope, and the relative density of backfill soil are changed. In addition, through using that conditions, CHBDC(2000, Canadian Highway Bridge Design Code) is evaluated if it could be applied to the design by comparing with the numerical analysis results. As the behaviour characteristics of the Corrugated Steel Plate Lining by CHBDC and the static numerical analysis are analyzed, both the methods show the same linear increases of the compressive stress according to the increase of the backfill height. The CHBDC of the dead load condition has very similar tendency by comparing with the result of the static numerical analysis.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.233-247
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• 2005

Most tunnel lining material which has been used in the domestic is a concrete. But many problems as the construction period, the cost, and the crack occurrence for the design, construction, and management were happened in the concrete lining. For this reason, many research institutes like the Korea Highway Corporation recognize the necessity of an alternate material development and grow on the interest for that. So in this study, the seismic behaviour characteristics for the application of the Corrugated Steel Plate Lining in cut-and-cover tunnel are evaluated as several conditions for the backfill height, the cutting slope, and the relative density of backfill soil are changed. The compressive stress which is calculated in the Corrugated Steel Plate Lining by the seismic load is decreased as the backfill height increases and the cut slope grows gentle. Also, the moment shows the tendency of decrease according to the increase of the backfill height. But in the case of the relative density of the backfill soil is small, the moment increases according to the increase of the backfill height and affects the dynamic behaviour characteristic. So it is considered that the relative density of the backfill soil is also the important point. As the result in analyzing the seismic response characteristics of the reinforcement spacing of the Corrugated Steel Plate, the variation in the compressive force is hardly happened, but the moment and the shear force increase on the reinforcement spacing being narrow.