• Title/Summary/Keyword: dB difference

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THE EFFECT OF IMMERSION DISINFECTION ON THE DIMENSIONAL STABILITY OF RUBBER IMPRESSION MATERIALS (침적 소독이 고무 인상재의 크기 안정성에 미치는 영향)

  • Min, Geun-Nam;Vang, Mong-Sook
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.3
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    • pp.496-505
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    • 1998
  • The purpose of this study was to evalute the effect of immersion disinfection on the dimensional stability of rubber impression materials. The metallic master model was made in order to simulate the intraoral arch form. Impressions were made from four impression materials (Exaflex, Extrude, Reprosil, Impregum-F) and immersed in three disinfectant solutions (Wydex, Vi-Pon, Potadine). Casts from the impressions were measured according to the interpreparation distance. The A-B and The B-D abutment distance were compared with the control group and disinfected groups. The results were as follows; 1. The measurements of the stone cast increased relative to the master model and there was a significant difference (P<0.05). 2. The relative dimensional change of the stone cast as compared with master model ranged from 0.10% to 0.56% in the A-B distance and ranged from 0.04% to 0.27% in the B-D distance. 3. The dimensional change of the disinfected groups as compared with the control group was significantly different in the three impression materials except for Impregum-F (P<0.05). 4. The relative dimensional change of the disinfected groups compared with the control group ranged from 0% to 0.20% in the A-B distance and ranged from -0.09% to 0.11% in the B-D distance. These results suggest that immersion disinfection of rubber impression materials by chemical disinfectants causes very small dimensional change and the change is clinically acceptable for prothesis fabrication

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A Dual-Channel 6b 1GS/s 0.18um CMOS ADC for Ultra Wide-Band Communication Systems (초광대역 통신시스템 응용을 위한 이중채널 6b 1GS/s 0.18um CMOS ADC)

  • Cho, Young-Jae;Yoo, Si-Wook;Kim, Young-Lok;Lee, Seung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.43 no.12 s.354
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    • pp.47-54
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    • 2006
  • This work proposes a dual-channel 6b 1GS/s ADC for ultra wide-band communication system applications. The proposed ADC based on a 6b interpolated flash architecture employs wide-band open-loop track-and-hold amplifiers, comparators with a wide-range differential difference pre-amplifier, latches with reduced kickback noise, on-chip CMOS references, and digital bubble-code correction circuits to optimize power, chip area, and accuracy at 1GS/s. The ADC implemented in a 0.18um 1P6M CMOS technology shows a signal-to-noise-and-distortion ratio of 30dB and a spurious-free dynamic range of 39dB at 1GS/s. The measured differential and integral non-linearities of the prototype ADC are within 1.0LSB and 1.3LSB, respectively. The dual-channel ADC has an active area of $4.0mm^2$ and consumes 594mW at 1GS/s and 1.8V.

The Influence of Dietary Characteristics on the Milk Quantity and Quality of Riverine Buffaloes: Estimate of the Energy/Protein Requirements, for a Medium-high Production, in the First Ninety Days of Lactation

  • Terramoccia, S.;Bartocci, A.;Giovanni, S. Di;Bartocci, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.3
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    • pp.335-340
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    • 2012
  • The data used came from two trials undertaken under the same climatic conditions (spring-summer). In both trials pluriparious buffaloes were utilized similar in weight, body condition score, and milk production from the previous year. From the first trial the data used was from the sub-period 23-88 DIM provided by seven animals fed ad libitum with diet A (6.69 MJ/kg DM; 158.30 g/kg of crude protein) with a forage/concentrate ratio of 48/52. From the second trial the data used was from the sub-period 33-90 DIM provided by seven animals fed ad libitum with diet B (6.63 MJ/kg DM; 179.50 g/kg of crude protein) and by seven animals fed ad libitum with diet C (5.99 MJ/kg DM; 155.40 g/kg of crude protein), each of the diets had the same forage/concentrate ratio (53/47). A significant difference was found in milk production between group B and C (13.08 vs. 11.56 kg/d, p<0.05), an intermediate production (12.10 kg/d) was noted in group A. A significant difference was found between fat (76.58 vs. 69.24 g/kg, p<0.05), protein (46.14 vs. 43.16 g/kg, p<0.05) and casein (39.94 vs. 34.98 g/kg, p<0.05) of the milk of group B with respect to group A. The milk of group C gave fat values (71.80 g/kg), protein (45.52 g/kg) and casein (39.06 g/kg) statistically equal to those of group B. The milk of groups B and C, in respect to the milk of group A, gave values of $K_{20}$ (1.77, 1.82 vs. 3.68 min, p<0.05), statistically lower and values of $A_{30}$ (48.28, 47.27 vs. 40.64 mm, p<0.05) statistically higher. Two simple linear regressions were calculated where the independent variable (x) was the daily standardized milk production, the dependent variable (y) or the daily intake of net energy or crude protein. Equation 1) NE (MJ/d) = 74.4049+2.8308${\times}$kg of normalized milk; equation 2) CP (kg/d) = 1.4507+0.1085${\times}$kg of normalized milk, both the equations were significant (p<0.05) with determination coefficients of 0.58 and 0.50 respectively. For a production of normalized milk that varies from 9 to 13 kg, the respective energy-protein concentrations fluctuate from 6.09 to 6.78 MJ/kg DM and from 148.00 to 174.46 g/kg DM.

사각형강목의 끝자루를 이용한 트롤어구의 어획선택성 연구 ( 2 ) - 다이아몬드형강목과 사각형강목의 선택성비교 - ( Studies on the Selectivity of the Trawl Net With the Square Mesh Cod-End ( 2 ) - Comparison of Diamond and Square Mesh Cod-End - )

  • Kim, Sam-Kon;Lee, Ju-Hee;Park , Jeong-Sik
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.30 no.3
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    • pp.172-181
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    • 1994
  • The mesh selectivity of diamond and suare mesh cod-ends at the Southern Korean Sea and the East China Sea were compared for Pampus argenteus, Trachurus japonicus, Trichiurus lepturus. Selection trials were carried out using diamond and square mesh cod-end by trouser type cod-end with cover net. of which the mesh cod-end has four types : A(51.2mm), B(70.2mm), C(77.6mm), D(88.0mm). Selection curves and selection parameters were calculated using a logistic model. The results obained are summarized as follows : 1. Harvest fish : In B. C and D type selection range and fifty percent selection length of the square mesh were about 21mm, 11mm : 12mm, 18mm and 34mm, 5mm higher than those of the diamond mesh, respectively. Selection factor of master curve for the diamond mesh was 1.54 and for the square mesh was 1.68. The optimum mesh size for the diamond mesh was 97.4mm and for the square mesh was 89.3mm, the difference was 8.1mm. 2. Horse mackerel : In A type, selection range was nearly the same for the diamond and the square mesh, but fifty percent selection length of the square mesh was 43mm higher than the diamond mesh. In B. C and D type, selection range and fifty percent selection length of the square mesh were about 6mm, 3mm : 24mm, 21mm and 11mm, 42mm higher than those of the diamond mesh, respectively. Selection factor of master curve for the diamond mesh was 2.37, for the square mesh was 2.77. The optimum mesh size for the diamond mesh was 78.1mm and for the square mesh was 66.8mm, the difference was 11.3mm. 3. Hair tail : In A, B and C type, selection range of the square mesh was about 34mm, 8mm, 60mm higher than those of the diamond mesh. Fifty percent selection length for the diamond mesh was about 5mm, 7mm, 8mm higher than that of the square mesh. Selection factor of master curve for the diamond mesh was 3.11, for the square mesh was 3.48. The optimum mesh size for the diamond mesh was 64.3mm and for the square mesh was 57.5mm, the difference was 6.8mm.

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Error Concealment Using Inter-layer Correlation for Scalable Video Coding

  • Park, Chun-Su;Wang, Tae-Shick;Ko, Sung-Jea
    • ETRI Journal
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    • v.29 no.3
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    • pp.390-392
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    • 2007
  • In this paper, we propose a new error concealment (EC) method using inter-layer correlation for scalable video coding. In the proposed method, the auxiliary motion vector (MV) and the auxiliary mode number (MN) of intra prediction are interleaved into the bitstream to recover the corrupted frame. In order to reduce the bit rate, the proposed method encodes the difference between the original and the predicted values of the MV and MN instead of the original values. Experimental results show that the proposed EC outperforms the conventional EC by 2.8 dB to 6.7 dB.

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Symbol Error Rate of 16-APSK Modulation (DVB-S2의 16-APSK 성능 분석)

  • Son, Jae-Seung;Lee, Yu-Sung;Park, Hyun-Cheol
    • Proceedings of the IEEK Conference
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    • 2004.06a
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    • pp.11-14
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    • 2004
  • Digital Video Broadcasting - Satellite (DVB-S) [1] (EN 300 421(bibliography)) was introduced as a standard in 1994. However, by combing with higher order modulation, promise more powerful alternatives to the DVB-S / DVB-DSNG coding and modulation schemes. Variable rate coding and modulation (VCM) may employed to provide different levels of error protection to different service components. Adaptive coding and modulation (ACM) provides more exact channel protection and dynamic link adaptation to propagation conditions, targeting each individual receiving terminal. By these reasons, DVB-S2 introduced. This paper derives exact symbol error rate(SER) of 16-Amplitude Phase Shift Keying(APSK) modulation by using Craig's formula. 16-APSK modulation is used in DVB-S2. The difference between Union Bound and Craig's formula is 1.26dB in low SNR and 0.1dB in high SNR.

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A Study on Silica based 4$\times$4 Optical Star Coupler with Tapered Coupling Structure (테이퍼 결합구조를 갖는 4$\times$4 성형 결합기에 관한 연구)

  • 윤현성;김정근
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.983-986
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    • 1998
  • Inthis paper, we design 4$\times$4 optical star coupler with tapered coupling structure. The 4$\times$4 optical star coupler consists of four 3dB couplers and a 100% coupler with tapered structure. This star coupler is designed by the 2 dimension FD-BPM(finite difference beam propagation method) using TBC(transparent boundary condition). consequently, the maximum power unbalance ratios of relative output power from each of the output waveguides for each of input guides are less than 0.1dB, and the transmission efficiency is more than 99%.

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Design of a Dielectric Resonator Filter with Improved Flatness Passband for WiBro band (통과대역 내 평탄도를 개선한 휴대인터넷 대역 유전체 공진기 여파기 설계)

  • Lee, Song-Yi;Yun, Sang-Won
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2005.11a
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    • pp.13-16
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    • 2005
  • Many mobile communication systems require bandpass filter with sharp skirt characteristics and consequently a filter was formed by more order. It needs to improve flatness in passband. In this paper, amplitude equalizer was used to improve the flatness of passband. We modified Chebyshev prototype filter by use of network synthesis and computed the prototype elements for Shaping filter. We designed and realized a 13-order combline bandpass filter and 4-order amplitude equalizer with coaxial dielectric resonators at WiBro band. The measured results show $\pm$0.82 dB amplitude difference in passband, 6 dB improved flatness.

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Soundscape for Gwang-Ju Riverside (광주천변의 사운드스케이프 현황)

  • Song, Hyuk;Park, Hyeun-Ku;Song, Min-Jeoung;Lee, Tae-Kang;Kim, Hang
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.05a
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    • pp.603-606
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    • 2005
  • This study is to make good acoustic environment around Gwang-ju riverside and performed survey and measurement of soundscape. The survey was focused on the types of sound producing. The results of measurement and analysis are as follows: 1) The types of sound at reverside were twenty and the Leq(equivalent noise level) was ranging from 50 dB(A) to 76 dB(A). The dominant sound was road traffic noise. 2) In the upperstream and the downstream, the sound of wind, bird and water was observed. 3) In the inner city, the water sound was produced by the difference of the height of the weir to mask the road traffic noise.

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Response of Annoyance for Impulsive Noise - Focusing on the Construction Noise - (충격성 소음에 대한 성가심 반응 - 건설공사장 소음을 중심으로 -)

  • Kim, Deuk-Seong;Jang, Seo-Il;Jeon, Hyeong-Jun;Lee, Yeon-Su
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2007.11a
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    • pp.1191-1196
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    • 2007
  • This research presents a laboratory study about an annoyance of impulsive sound caused by construction site(breaker and blasting). The sources are sampled from outdoor noise and their levels range from 40 to 75 dB at the interval of 5dB. The noise unit is based on A-weighted sound exposure level (ASEL; $L_{AE}$). To make equal ASEL of outdoor noise, finite impulse response (FIR) filter is applied to the originally sampled source to include the effect of distance attenuation. The evaluation method of jury test adopted a Semantic Difference Method (SDM). In the result of the Jury test for impulsive noise, the annoyance response of blasting noise was higher than that of breaker noise.

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