• Journal of the Korean Ceramic Society
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• v.56 no.2
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• pp.173-177
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• 2019

Thermal properties of a SiO₂-B₂O₃-BaO ternary glass system depending on compositional change of BaO have been examined to find a proper sealing material for reversible oxide cells. Glass transition temperature and thermal expansion coefficients increased simultaneously up to 55 mol% of BaO content. The structural role of BaO with regard to the thermal properties has been discussed on the basis of Raman spectroscopy results. Flowability of the glass at sealing temperature has been examined with packed glass powders of 12 mm diameter along with a high temperature optical microscope. The practical sealing property of the glass was also examined with YSZ coated with NiO-yittria stabilized zirconia (NiO-YSZ) and it showed good adhesion without noticeable reaction with NiO-YSZ layer.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.10 no.4
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• pp.530-538
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• 1999

In this paper, design of rectangular iris waveguide filter for the microwave broadcasting transponder using WR137 is applied to the modified ${TE^x}_{mn}$ mode theory in order to exactly analyze the characteristic of the waveguide discontinuity. We designed and fabricated the rectangular iris waveguide filter with the bandwidth 47 MHz for the microwave broadcasting transponder applied the conjugate gradient method to the modified ${TE^x}_{mn}$ mode theory. The results show a good characteristics that the $S_{11}$ and $S_{21}$ are -23 ㏈, -0.56 ㏈ and the maximum VSWR is below 1.02 in the passband.

• Journal of IKEEE
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• v.17 no.4
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• pp.511-516
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• 2013

This paper presents a SDM using the FDPA technique. The FDPA technique is the added feedback path which is the delayed path of DAC output. The designed SDM increases the SNR by adding the delayed digital feedback path. The proposed SDM is easily implemented by eliminating the analog feedback path. Through the MATLAB modeling, the optimized coefficients are obtained to design the SDM. The designed SDM has a power consumption of $220{\mu}W$ and SNR(signal to noise ratio) of 81dB at the signal-bandwidth of 20KHz and sampling frequency of 2.56MHz. The SDM is designed using the $0.18{\mu}m$ standard CMOS process.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.6
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• pp.1-6
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• 1989

Narrowband bandpass weveguide filters using inductive post obstacles in rectangular waveguide are designed and constructed to have an equal-ripple bandwidth of 50MHz (0.56% fractional band-width) at a center frequency of 9GHz. Both the triple-post and the single-post configurations are realized and compared. The measured center frequency, bandwidth, and attenuation characteristics for both filters show good agreement with the theoretical calculations. When the two filters are compared, the insertion loss characteristic of the triple-post filter is better than that of the single-post filter by 0.8dB at the passband.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.2
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• pp.257-262
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• 2008

In this paper, the key parameters of $CO_2$ laser(focus depth, air blow rate, total laser beam time, number of pulse) are experimented for thru-hole and scribing line on AIN(aluminum nitride) substrate with high thermal conductivity. And, microstrip line & spiral planar inductor are fabricated on AIN substrate using 5 um Cu-plating with self-masking technique. The microstrip line of AIN has 0.1 dB/mm attenuation at 10 GHz and 6 nH spiral planar inductor has 56 maximum quality factor at 1 GHz. Thus, the AIN substrate is promising for GHz applications of high power area.

• Parasites, Hosts and Diseases
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• v.56 no.4
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• pp.365-370
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• 2018

To confirm that Bartonella and Wolbachia were carried by sheep keds (Melophagus ovinus) in southern Xinjiang of China, 17 M. ovinus samples, which were collected in Aksu Prefecture, Xinjiang, were randomly selected. In this study, the Bartonella gltA and Wolbachia 16S rRNA gene were amplified through conventional PCR and the sequence of those amplified products, were analyzed. The results demonstrated that Bartonella was carried by all of the 17 sheep keds and Wolbachia was carried by 15 out of them. Bartonella was identified as B. melophagi. Three strains of Wolbachia were supergroup F and 1 strain has not been confirmed yet. It is the first report about Wolbachia supergroup F was found in sheep keds and provided the molecular evidence that B. melophagi and Wolbachia supergroup F were carried by sheep keds in Aksu Prefecture of southern Xinjiang, China. The 2 pathogens were found in sheep keds around Taklimakan Desert for the first time.

• Korean Journal of Plant Tissue Culture
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• v.28 no.6
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• pp.323-328
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• 2001

In order to optimize the conditions of callus induction and plant regeneration in seed culture of Italian ryegrass, the effects of basic medium and carbon sources on seed culturability and genotypic difference of plant regenerability were investigated. MS medium was better than N6 and B5 medium in enhancing callus growth and plant regeneration. Sucrose was superior to maltose in plant regeneration as carbon source in the medium. The genotypic difference in plant regenerability was obvious among four cultivars of Italian ryegrass tested. 'Rio' and 'Jeanne' showed to have higher regenerability with the frequency of 38% and 56%, respectively.

• Journal of the Korean Chemical Society
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• v.56 no.4
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• pp.468-472
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• 2012

Efficient one-pot microwave-assisted synthesis of various benzo-[1,4]-oxazinones via Smiles rearrangement is described. Treatment of 2-chloroacetamide, substituted 2-chlorophenols and cesium carbonate in MeO-PEG-OMe (2,000) as solvent afforded the corresponding benzo-[1,4]-oxazinones and 1H-pyrido[2,3-b][1,4]-oxazin-2-(3H)-one as moderate yield.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.3
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• pp.460-465
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• 2007

In this paper, the pipelined A/D converter with multi S/H stage structure is proposed for high resolution and high-speed data conversion rate. In order to improve a resolution and operational speed, the proposed structure increased the sampling time that is sampled input signal. In order to verify the operation characteristics 20MS/s pipelined A/D converter is designed with two S/H stage. The simulation result shows that INL and DNL are $0.52LSB{\sim}-0.63LSB$ and $0.53LSB{\sim}-0.56LSB$, respectively. Also, the designed Analog-to-Digital converter has the SNR of 43dB and power consumption is 18.5mW.

• Korean Journal of Crystallography
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• v.6 no.2
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• pp.63-68
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• 1995

The crystal structure of fenothiocarb(S-4-phenoxybutyl dimethylthiocarbamate), C13H19NO2S is monoclinic, space group P21/c, a=9.045(1)Å, b=14.577(2)Å, c=10.727(2)Å, β=103.56(1)°, Z=4, V=1375.20(6)Å3, Dc=1.23g/cm3, λ(Mo-Kα)=0.71069Å, μ=2.3cm-1, F(000)=544, temperature : 293±3K, R=0.049 for 1543 unique observed reflections. The structure was determined by direct method and refined by full-matrix least squares method. The molecules are contacted to the c axis with two fold screw and van der Waales force.