• Title/Summary/Keyword: Q value

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Estimation of R-value and Uniaxial Compressive Strength of Rocks around the King Sejong Station, Barton Peninsula, Antarctica from SilverSchmidt Q-value (실버슈미트 Q값으로부터 남극 바톤반도 세종과학기지 주변 암석의 R값 및 일축압축강도 추정)

  • Lim, Hyoun-Soo;Jang, Bo-An;Kim, Jung-Han;Kang, Seong-Seung
    • Tunnel and Underground Space
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    • v.25 no.2
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    • pp.199-209
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    • 2015
  • The rebound hardness test using the SilverSchmidt hammer was performed for diorite, granodiorite, and andesite exposed around the King Sejong Station, Barton peninsula. Then, the R-value and uniaxial compressive strength (UCS) of these rocks were estimated from the Q-values which were obtained from the SilverSchmidt hammer. The Q-value of diorite was distributed in the range from 67.0 to 89.5, granodiorite of the range from 57.5 to 89.0, and andesite of the range from 58.0 to 76.5. The average Q-values of diorite, granodiorite, and andesite were 76.0, 72.0, and 67.0, respectively. The converted UCS of diorite was distributed in the range from 118 to 195 MPa, granodiorite of the range from 91 to 193 MPa, and andesite of the range from 92 to 148 MPa. The average UCS of diorite, granodiorite, and andesite were 147, 136, and 117 MPa, respectively. The converted R-value of diorite was distributed in the range from 53.0 to 72.2, granodiorite of the range from 45.4 to 71.8, and andesite of the range from 45.8 to 60.9. The average Q-values of diorite, granodiorite, and andesite were 60.0, 58.0, and 53.0, respectively. The R-value was represented approximately 20% lower than the Q-value. In conclusion, it will be possibile that the R-value and UCS of rocks under the extreme area from the SilverSchmidt Q-value are evaluated.

EPCglobal Gen 2 Tag Identification Performance Analysis Modifying the C model in the Q Algorithm (EPCglobal Gen 2 Q 알고리즘에서 C 모델에 따른 태그 인식 성능 평가)

  • Park, Jong-Myung;Cho, Sung-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.12B
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    • pp.1444-1451
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    • 2009
  • This paper first proposes diverse C determining models in the Q algorithm which is proposed in the EPCglobal C1 Gen 2 standard and then compares and analyzes its performance. EPCglobal C1 Gen 2 standard proposes the slot-count (Q) selection algorithm for multiple tag identification environment, but there is no such definition for the C value which modifies the Q value depending on collision or no reply. During the tag anti-collision process, the Q algorithm adds C to the Q when there is a collision and reduces the Q by C when there is no reply. The modified Q value updates new slot-counts for tags which determines the tag identification speed, so the C value is an important factor. However, many researches only intend to increase the tag identification speed by proposing a new method or modifying the Q algorithm without any research about the C value. This paper suggests diverse C models which satisfies the EPCglobal C1 Gen 2 and analyzes their performance in the multi tag identification environment. The result of this paper can be used as an index for future researches on EPCglobal C1 Gen 2 C models and multiple tag identification performance.

The Experimental Method of Measuring Q (Q의 실험적 측정법)

  • Kim, Dong-Hak;Lee, Jeong-Hyun;Kang, Ki-Ju
    • Proceedings of the KSME Conference
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    • 2003.04a
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    • pp.285-291
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    • 2003
  • An experimental method to measure Q-parameter in-situ is described. The basic idea comes from the fact that the side necking near a crack tip indicates the loss of stress triaxiality, which can be scaled by Q. From the out-of-plane displacement and the in-plane strain near the surface of side necking, stress field averaged through the thickness is calculated and then Q is determined from the difference between the stress field and the HRR field corresponding to the identical J-integral. To prove the validity, three-dimensional finite element analysis has been performed for a CT configuration with side-groove. Q-value which was calculated directly from the near-tip stress field is compared with that determined by simulating the experimental procedure according to the proposed method, that is, the Q-value determined from the lateral displacement and the inplane strain. Also, the effect of location where the displacement and strain are measured is explored.

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A Study on the Correlation between Standard Penetration Resistance Value and Static Cone Penetration Resistance Value of the Soft Ground Subsurface of Yongdong Area (표준관입저항치와 정적콘관입저항치의 상관성에 관한 연구 - 영동지역의 연약지반을 중심으로 -)

  • Kim, Jinam;Park, Heunggyu
    • Journal of the Korean GEO-environmental Society
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    • v.7 no.5
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    • pp.13-20
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    • 2006
  • We have conducted standard penetration tests and static cone penetration tests that are widely used the land base examination on the soft ground subsurface of Yongdong area, and examined the correlation between them. We have also made a comparative analysis of the correlation between the indoor tests on the materials collected on the site and on-the-spot penetration tests. The results are as follows : The relationship between Standard Penetration Test N-value and Dutch Cone Tset show $Q_c=1.93N+0.29$ for organic soil, $Q_c=2.19N+0.20$ for clay, $Q_c=2.34N+1.06$ for silt, $Q_c=3.02N+0.54$ for silty sand, and $Q_c=3.47N+0.46$ for sand. In this case of sand $Q_c/N$ increases when the soil particles are larger. The relationship between standard penetration test N-value and Unconfined Compression Strength $q_u$ show $q_u=0.11N+0.03$ for organic soil, $q_u=0.11N+0.25$ for clay, and $q_u=0.18N-0.03$ for silt.

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The Impact of IFRS Adoption on Firm Value in Korea and China - Evidence using Tobin's Q (국제회계기준 도입이 기업가치에 영향을 미치는가?: 토빈의 Q 모형을 이용한 한국과 중국의 실증비교연구)

  • Jang, Ji-Kyung
    • The Journal of the Korea Contents Association
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    • v.14 no.7
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    • pp.427-434
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    • 2014
  • In this research, it is empirically tested whether firm value after the adoption of IFRS is increased in Korea and China using Tobin's Q model. In Korea, IFRS was mandatorily adopted in 2011 for all companies. China mandated IFRS conversion for public traded companies starting 2007. The revisions bring Chinese standards closer to the IFRS benchmark of internationally recognized quality, but the new standards will not be word-for-word translations of IFRS, though they founded on similar principle. We expect the different adoption process between Korea and China can make different impact of IFRS on firm value. The results are summarized as follows. First, Tobin's Q seems to be increased after the adoption of IFRS, and the firm value is significantly different between before and after IFRS adoption in Korea. Second, Tobin's Q seems to be increased after the adoption of IFRS, but the analysis by t-test is not significantly higher for post IFRS. These results could be a good finding in that the impact of IFRS adoption on firm value is different by adoption process.

Global Soft Decision Based on Improved Speech Presence Uncertainty Tracking Method Incorporating Spectral Gradient (스펙트럼 변이 기반의 향상된 음성 존재 불확실성 추적 기법을 이용한 Global Soft Decision)

  • Kim, Jong-Woong;Chang, Joon-Hyuk
    • The Journal of the Acoustical Society of Korea
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    • v.32 no.3
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    • pp.279-285
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    • 2013
  • In this paper, we propose a novel speech enhancement method to improve the performance of the conventional global soft decision which is based on the spectral gradient method applied to the ratio of a priori speech absence and presence probability value (q). Conventional global soft decision scheme used a fixed value of q in accordance with the hypothesis assumed, but the proposed algorithm is a technique for improving the speech absence probability which is applied adaptively variable value of q according to the speech presence or absence in the previous two frames and the conditions of the spectral gradient value. Experimental results show that the proposed improved global soft decision method based on the spectral gradient method yields better results compared to the conventional global soft decision technique based on the performance criteria of the ITU-T P. 862 PESQ (Perceptual Evaluation of Speech Quality).

Probabilistic Q-system for rock classification considering shear wave propagation in jointed rock mass

  • Kim, Ji-Won;Chong, Song-Hun;Cho, Gye-Chun
    • Geomechanics and Engineering
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    • v.30 no.5
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    • pp.449-460
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    • 2022
  • Safe underground construction in a rock mass requires adequate ground investigation and effective determination of rock conditions. The estimation of rock mass behavior is difficult, because rock masses are innately anisotropic and heterogeneous at different scales and are affected by various environmental factors. Quantitative rock mass classification systems, such as the Q-system and rock mass rating, are widely used for characterization and engineering design. The measurement of rock classification parameters is subjective and can vary among observers, resulting in questionable accuracy. Geophysical investigation methods, such as seismic surveys, have also been used for ground characterization. Torsional shear wave propagation characteristics in cylindrical rods are equal to that in an infinite media. A probabilistic quantitative relationship between the Q-value and shear wave velocity is thus investigated considering long-wavelength wave propagation in equivalent continuum jointed rock masses. Individual Q-system parameters are correlated with stress-dependent shear wave velocities in jointed rocks using experimental and numerical methods. The relationship between the Q-value and the shear wave velocity is normalized using a defined reference condition. This relationship is further improved using probabilistic analysis to remove unrealistic data and to suggest a range of Q-values for a given wave velocity. The proposed probabilistic Q-value estimation is then compared with field measurements and cross-hole seismic test data to verify its applicability.

REMARK ON THE MEAN VALUE OF L(½, χ) IN THE HYPERELLIPTIC ENSEMBLE

  • Jung, Hwanyup
    • Journal of the Chungcheong Mathematical Society
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    • v.27 no.1
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    • pp.9-16
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    • 2014
  • Let $\mathbb{A}=\mathbb{F}_q[T]$ be a polynomial ring over $\mathbb{F}_q$. In this paper we determine an asymptotic mean value of quadratic Dirich-let L-functions L(s, ${\chi}_{{\gamma}D}$) at the central point s=$\frac{1}{2}$, where D runs over all monic square-free polynomials of even degree in $\mathbb{A}$ and ${\gamma}$ is a generator of $\mathbb{F}_q^*$.

Anti-collision Algorithm with Early Cancellation of Query Round in RFID Systems

  • Lim, In-Taek
    • Journal of information and communication convergence engineering
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    • v.7 no.3
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    • pp.292-296
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    • 2009
  • The performance of anti-collision algorithm in RFID systems, which are based on FSA algorithm, may be affected by the frame size a query round. In this paper, an anti-collision algorithm with early cancellation of query round is proposed to enhance the performance of EPCglobal Class-1 Gen-2. The Q-algorithm calculates a Q value to determine the next frame size during a query round. In the proposed algorithm, if the new Q value is different from the previous one, the reader transmits a QueryAdjust command to cancel the current query round. The simulation results show that the proposed algorithm can have a stable performance irrespective of the C value of Q-algorithm and the number of tags.