• Applied Microscopy
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• v.35 no.3
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• pp.105-112
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• 2005

In this review, the important ideas of coherence theory are introduced. The transfer function and damping envelopes of the microscope due to temporal and spatial coherence are described. The passbands and the condition of Scherzer focus are also disscussed in associated with the resolution of transmission electron microscope.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.23 no.6
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• pp.41-46
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• 2023

Design of W-band TE10 to TEM mode converter for radial power combiner is proposed in this paper. The proposed structure is used with generally available pin to realize TEM mode and is designed to convert TE10 to TEM mode gradually using 2-step impedance transformer and back short. The pin of proposed mode converter is well bonded to the housing so that environment conditions such as vibration or shock are not affected. The proposed mode converter, in a back-to-back configuration, has less than 1.55 dB insertion loss and more than 10 dB return loss from 92.5 GHz to 97.7 GHz. Proposed converter is expected compact radar and various applications requiring for high power and stable environment conditions.

• Korean Journal of Veterinary Service
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• v.37 no.4
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• pp.225-231
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• 2014

In this study, 185 cefotaxime-resistant Escherichia coli were isolated from different stages of a wastewater treatment plant (WWTP) in Daegu in Korea. Among them, 99.5% (184 isolates) originated from raw sewage and 0.5% (1 isolates) from the final effluent. Cefotaxime-resistant E. coli were high resistant to ampicillin, piperacillin, cefazolin, cephalothin, cefachlor and cefamandole (99.5~100%). About 93% of the cefotaxime-resistant E. coli were extended-spectrum ${\beta}$-lactamases (ESBL)-producing E. coli. The $bla_{TEM+CTX}$ gene was the most predominant of the ESBL genes (72.5%), followed by $bla_{CTX-M}$ (16.2%), $bla_{TEM}$ (8.7%), $bla_{TEM+CTX+SHV}$ (1.1%), $bla_{TEM+SHV}$, $bla_{TEM+OXA}$, and $bla_{TEM+CTX+SHV}$ (respectvely 0.5%). Class 1 and 2 integron were found in 49.7% and class 3 integron was not found. All of integron positive isolates were multiresistant (i.e. resistant to four or more antibiotics). Our findings showed WWTP is contaminated with antibiotic resistant bacteria with resistance genes.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.16 no.3
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• pp.1-7
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• 2020

To provide a design direction for high efficiency thermoelectric module(TEM) dehumidifiers, the effects of design factors of TEM dehumidifiers on dehumidification energy efficiency and performance were numerically investigated. The design factors considered in this study are the TEM capacity, the performance of heat exchangers on the heating and cooling surfaces of the TEM. The higher capacity of the TEM results the higher dehumidification energy efficiency and performance at some operating voltage. The enhanced performance of the heat exchanger on heating surface increased the dehumidification energy efficiency and performance at all the operating voltage. The enhanced performance of the heat exchanger on cooling surface decreased the dehumidification energy efficiency and performance at all operating voltage.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.221-227
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• 2000

This study was performed to investigate the biological characteristics of twenty isolates of extended spectnlm $\beta$-lactamase (ESBL) producing Klebsiellapnezm~onia collected kom the various clinical specimens of three hospitals in Pusan. Isoelectric focusing (IEF) and PCR were used to determine the types of $\beta$-lactamase gene in this study. Twenty isolates of ESBL producing Klebsiellnp~ieun~or~iae could be divided by PCR, such as TEM type (I1 strains), SHV type (8 strains); non TEM non SHV type (1 strain). In the isoelechic focusing test, the PI of TEM type was 5.2-6.0 and that of SHV type was 6.9-7.4. According to the pI value and PCR bands, twenty strains of ESBL Klebsiellapneumoniae were divided into 5 types: TEM type @I 5.2-6.0; 1080 bp on PCR band), TEM + SHV type (pI 5.2-6.0; andpI 7.0-7.4; 1080 bp and 599 bp on PCR band), SHV type (pl7.0-7.4; 599 bp on PCR band), non TEM non SHV type, and otber type (PCR result was SHV type but pI was not detected).

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.6 no.2
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• pp.165-175
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• 1996

Fourteen(14) large commercial buildings located in Seoul with friable sprayed-on surface insulation material on ceiling were investigated for fiber types in bulk material and for airborne fiber concentrations in buildings by transmission electron microscopy (TEM) in order to compare the results with those by polarized light microscopy (PLM) and phase contrast microscopy (PCM). The results were as follows: 1. Chrysotile asbestos was found in one bulk sample out of total 14 bulk samples collected. Glass fiber and mineral wool were the two major constituents of the bulk samples. 2. The Na-Mg-Si-Ca-Fe-Al ratios of the EDX spectra which were normalized with the Si peak were 0-1.0-10-8.3-4.0-4.0 in mineral wool and 0-5-10-21-0-0 in chrysotile asbestos, respectively. 3. Airborne fiber concentrations were log-normalcy distributed and the geometric mean (geometric standard deviation) fiber concentrations by TEM in the underground parking lots and inside buildings were 0.0048 f/cc(1.93) and 0.0040 f/cc(2.27), respectively with no statistical difference. In the outdoor ambient air, statistically significantly lower concentration of 0.0018 f/cc(2.04) was measured. 4. The TEM/PCM ratios of airborne fiber concentrations ranged 0.5 - 2.0 for 80 % of airborne samples analyzed, end the regression equation between TEM and PCM was PCM=-0.2724+1.1355(TEM) with the coefficient of determination $R^2=0.52$. The results of this study confirmed that the sprayed-on surface insulation material found in some commercial buildings may possibly be contaminated with asbestos fiber. Since statistically significant relationship of fiber concentrations measured by PCM and TEM inside buildings and ambient air was found, previous results by PCM in ambient air could be used to estimate the ambient fiber concentrations in knowing the ratio of TEM/PCM.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.1
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• pp.91-99
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• 2009

In this paper, a standard field generation method using a micro-TEM ceil is described and its measurement uncertainty is evaluated. The standard field generation system consists of an auto-leveling signal source, a micro-TEM cell operating up to 1.2 GHz, and a power measuring Instrument using a thermistor mount. Measurement results of a field strength key comparison (CCEM.RF-K20) for the field strength of 20 V/m at frequencies between 10 MHz and 1 GHz are presented for validating the standard field generation method.

• Geophysics and Geophysical Exploration
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• v.20 no.3
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• pp.121-128
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• 2017

Interpretation of time-domain electromagnetic (TEM) data has been made mostly based on one-dimensional (1-D) inversion scheme in Korea. A proper interpretation of TEM data should employ 3-D TEM forward and inverse modeling algorithms. This study developed a 3-D TEM modeling algorithm using a finite difference time-domain (FDTD) method with staggered grid. In numerically solving Maxwell equations, fictitious displacement current is included based on an explicit FDTD method using a central difference approximation scheme. The developed modeling algorithm simulated a small-coil source configuration to be verified against analytic solutions for homogeneous half-space models. Further, TEM responses for a 3-D anomaly are modeled and analyzed. We expect that it will contribute greatly to the precise interpretation of TEM data.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.1
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• pp.177-182
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• 2016

Geofence is a generic concept for describing geographic aspects of PoI(Point of Interest) enabling users to proactively induce context-based actions. However there is no need to maintain continuity when you reflect geofence in case of temporary events, accidents and isolation. Therefore we propose a geofence platform so-called TemG by adding time-limited information to support PoI. The proposed geofence platform TemG ensures the persistency and continuity of geofence. Furthermore, the proposed TemG can not only provide to automatically activate or deactivate the specified geofence during a period of timestamp but also support to the basic context-aware service knowing in/out in the zone. In the near future, the proposed TemG will be need to extend HPS(Hybrid Positioning System) for IoT(Internet of Things).

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.2 no.1
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• pp.37-45
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• 1991

The electromagnetic field distribution within rectangular coaxial transmission lines (RCTL:TEM cells) is calculated using a numerical method. Boundary integral equations(BIE) considering equivalence theorem and extended boundary condition(EBC) in tapered region are used, thereby restricting the operational frequencies (0~130 MHz) below the cell cutoff frequency(130 MHz). The EM fields within NIST TEM cell ($1\times0.6\times2m$) are calculated by this method. The results of the numerical calcuation have a good agreement in the cross-sectional EM field distribution of TEM cell with 2-dimensional analysis results. Based on this method, the first cutoff freque- ncy in high order modes in the cell and the electric field polarization are considered.