• Journal of The Korean Association For Science Education
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• v.36 no.3
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• pp.435-443
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• 2016

The purpose of this study is to analyze the mismatch between instructional design and teaching practice of pre-service science teachers and to investigate the cause of these mismatches. Twenty pre-service science teachers took part in teaching practicum for four weeks from Apr. 2015 to May 2015 and we analyzed their lesson plans and videos of these lessons. After that, we interviewed the pre-service science teachers in order to know the cause of these mismatches and additional informations. The main findings are as follows. First, in the introductory stage, we found more mismatch in the "attention and motivation stimulation" area than any other area. Many pre-service science teachers corrected their 'motivation practice' in different forms. Second, we found out that the most mismatch occurred in the evolving stage. Many pre-service science teachers added learning contents in "learning content presentation" area. Third, in the closing stage, many pre-service science teachers omitted the "leaning content summary" area in the lack of time. Fourth, the number of mismatches by internal factors is similar of by external factors. The mismatches by external factors were mainly by feedback of guidance teacher and change by students' response. In addition, we discussed the implications related to reflective mentoring program, importance of guidance teacher, importance of time management etc.

• Journal of the Korean Geographical Society
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• v.48 no.2
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• pp.239-258
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• 2013

This study aims to examine that Jeollabuk-do 14 cities and counties's job creation policy would lead to a virtuous circle of the local economy through measuring the ratio of spatial mismatch. We suppose that the higher proportion of spatial mismatch in a city or county is, the lower multiplier effect contributes the local economy, especially in the income of residents and the influx of population. For the analysis, this study uses Korean Regional Employment Survey Micro-data and calculates the labor demand self-sufficiency(LDSS) rate of every local labor market for measuring the degree of spatial mismatch. Also we calculate the LDSS rate of employment status, industry, job classification and wage for testing the independency of local labor market. After analyzing, just Jeonju, Gunsan, Iksan, and Namwon could be regarded as independent local labor market where LDSS rates are above 75% in most criteria. But other local labor markets depend on outer labor supplies. For the development of regional economy, it is necessary to consider the creation of 'good jobs' that can induce the labor in parallel with the quantitative increase of employment.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.6
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• pp.488-490
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• 2008

A 75-year-old man with non-small cell lung cancer (NSCLC) underwent F-18 fluorodeoxyglucose (FDG) PET/CT for staging. PET/CT showed distant metastases to intra-abdominal lymph nodes (LNs) as well as bilateral mediastinal LNs (stage IV), He underwent PET/CT (restaging PET/CT) 1week after the completion of first-line chemotherapy (docetaxel+carboplatin). It showed markedly increased FDG uptake in primary tumor, whereas tumor size decreased significantly, compared to prior PET/CT. This lesion was aggravated on follow-up CT 3 months after the completion of chemotherapy. Although there are several reports that FDG PET has potential to evaluate early response to chemotherapy and prognosis, there are a few cases to show mismatch between FDG uptake and size on PET/CT. Thus we report a case of NSCLC showed increased FDG uptake of primary tumor while decreased tumor size on restaging PET/CT.

• Proceedings of the KIEE Conference
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• 2006.07b
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• pp.1159-1160
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• 2006

As the grid-connected photovoltaic power conditioning systems (PVPCS) are installed in many residential areas, this has raised potential problems of network protection on electrical power system. One of the numerous problems is an Island phenomenon. There has been an argument that because the probability of islanding is extremely low it may be a non-issue in practice. However, there are three counter-arguments: First, the low probability of islanding is based on the assumption of 100% power matching between the PVPCS and the islanded local loads. In fact, an island can be easily formed even without 100% power matching (the power mismatch could be up to 30% if only traditional protections are used, e.g. under/over voltage/frequency). The 30% power-mismatch condition will drastically increase the islanding probability. Second, even with a larger power mismatch, the time for voltage or frequency to deviate sufficient to cause a trip, plus the time required to execute the trip (particularly if conventional switchgear is required to operate), can easily be greater than the typical re-close time on the distribution circuit. And, third, the low-probability argument is based on the study of PVPCS. Especially, if the output power of PVPCS equals to power consumption of local loads, it is very difficult for the PVPCS to sustain the voltage and frequency in an island. Unintentional islanding of PVPCS may result in power-quality issues, interference to grid-protection devices, equipment damage, and even personnel safety hazards. So the verification of anti-islanding performance is strongly needed. In this paper, the authors propose the improved RPV method through considering power quality and anti-islanding capacity of grid-connected three-phase PVPCS in IEEE Std 1547 ("Standard for Interconnecting Distributed Resources to Electric Power Systems"). And the simulation and experimental results are verified.

• The Journal of the Acoustical Society of Korea
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• v.18 no.3E
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• pp.3-8
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• 1999

In speech recognition for real-world applications, the performance degradation due to the mismatch introduced between training and testing environments should be overcome. In this paper, to reduce this mismatch, we provide a hybrid method of spectral subtraction and residual noise masking. We also employ multiple model approach to obtain improved robustness over various noise environments. In this approach, multiple model sets are made according to several noise masking levels and then a model set appropriate for the estimated noise level is selected automatically in recognition phase. According to speaker independent isolated word recognition experiments in car noise environments, the proposed method using model sets with only two masking levels reduced average word error rate by 60% in comparison with spectral subtraction method.

• JSTS:Journal of Semiconductor Technology and Science
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• v.15 no.1
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• pp.96-100
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• 2015

Adaptive background gain calibration loop for multi-lane serial links is proposed. In order to detect and cancel gain mismatches between lanes, a single digital loop using a ${\sum}{\Delta}$ ADC is employed, which provides a real-time adaptation of gain variations and is shared among all lanes to reduce power and area. Evaluation result showed that gain mismatches between lanes were well calibrated and tracked, resulting in timing budget at $10^{-6}$ BER increased from 0.261 UI to 0.363 UI with stable loop convergence.

• JSTS:Journal of Semiconductor Technology and Science
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• v.16 no.5
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• pp.624-629
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• 2016

The influence of electron and hole (EH) distribution on two-transistor (2T) silicon-oxide-nitride-oxide-silicon (SONOS) embedded nonvolatile memory (eNVM) is investigated in terms of reliability. As PE (program/erase) cycles are repeated, it is observed that the electron distribution in the nitride layer becomes wider. It leads to the EH distribution mismatch, which degrades the reliability of 2T SONOS eNVM.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.553-554
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• 2008

In a general way, Current scaling DACs are used in wireless communication systems. But there are degradations of important factors because of mismatch of current source corresponding to high resolution. To solve the problem, Calibration methods are researched lately. Mismatch of current source is corrected by Calibration method and then corrected current values are delivered to Core DAC. As a results, Degradations of important factors that produced by increment of non-linearity are suppressed by calibration method.

• Proceedings of the Acoustical Society of Korea Conference
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• spring
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• pp.210-213
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• 1999

수동소나체계에서 음원의 위치와 관련된 매개변수를 산출하기 위해 정합장처리(Matched Field Processing)가 이용된다 본 연구에서는 수직선배열센서를 이용한 정합장처리에서 음원 위치추정에 영향을 미치는 다양한 요인 중, 수직음속분포 오정합(mismatch)에 의한 영향을 MV 프로세서 (Minimum Variance Processor)를 이용하여 모의실험함으로써 그 결과를 분석하였다. 천해 모의환경에서 동일한 기울기로 증감하는 수직음속분포 오정합은 음원 위치추정에서 거리성분의 오차를 가지며, 상이한 기울기를 갖는 수직음속분포 오정합은 거리와 수심 성분의 오차가 유발됨을 확인할 수 있었다. 심해 모의 환경에서 수직음속분포 오정합은 거리와 수심 성분의 오차가 유발되고, 거리추정의 전반적인 경향은 천해의 동일한 기울기를 가지는 경우와 유사함을 확인할 수 있었다.

• Journal of the Korean Society for Precision Engineering
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• v.30 no.8
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• pp.802-808
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• 2013

Thermal barrier coating (TBC) is used to protect substrates and extend the operating life of gas turbines in power plant and aeronautical applications. The major causes of failure of such coatings is spallation, which results from thermal stress due to a thermal expansion coefficient mismatch between the top coating and the bond coating layers. In this paper, the effects of the material properties and the thickness of the top coating layer on thermal stresses were evaluated using the finite element method and the equation for the thermal expansion coefficient mismatch stress. In addition, we investigated a design technique for the top coating whereby thermal resistance is exploited.