• Title/Summary/Keyword: Basis sets

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Structures and Barrier Heights for the Internal Rotation of Ethyl Halides Caculated by ab initio Methods

  • Ryu, Ung-Sik;Lee, Yoon-Sup
    • Bulletin of the Korean Chemical Society
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    • v.15 no.3
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    • pp.221-227
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    • 1994
  • The barrier heights of the internal rotations for ethyl halides calculated by ab initio methods differ from those of experiments by more than 0.2 kcal/mol. The use of basis sets larger than the $6-31G^{\ast}$ set and the inclusion of correlation do not improve the agreement between the calculated and experimental values. The zero-point vibration corrections are substantial in the HF calculations with $6-31G^{\ast}$ basis sets, but become negligible in the MP2 calculations with $6-311G^{{\ast}{\ast}}$ basis sets for $C_2H_5F\;and\;C_2H_5Cl$. It is shown that the rigid rotor approximation and the assumed shape of the potential curve as a cos2${\theta}$ curve could also be the sources of discrepancies between calculated and experimental values. Higher order perturbation corrections narrow the gap between experimental and theoretical values, but there still remains about 10% overestimate of 0.3 kcal/mol. Optimized geometries from the HF and MP2 calculations are in good agreement with those from experiments. Dipole moments calculated from the MP2 densities show slightly better agreement with experiments than those from the HF densities.

Generalization of Quantification for PLS Correlation

  • Yi, Seong-Keun;Huh, Myung-Hoe
    • The Korean Journal of Applied Statistics
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    • v.25 no.1
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    • pp.225-237
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    • 2012
  • This study proposes a quantification algorithm for a PLS method with several sets of variables. We called the quantification method for PLS with more than 2 sets of data a generalization. The basis of the quantification for PLS method is singular value decomposition. To derive the form of singular value decomposition in the data with more than 2 sets more easily, we used the constraint, $a^ta+b^tb+c^tc=3$ not $a^ta=1$, $b^tb=1$, and $c^tc=1$, for instance, in the case of 3 data sets. However, to prove that there is no difference, we showed it by the use of 2 data sets case because it is very complicate to prove with 3 data sets. The keys of the study are how to form the singular value decomposition and how to get the coordinates for the plots of variables and observations.

Discontinuous finite-element quadrature sets based on icosahedron for the discrete ordinates method

  • Dai, Ni;Zhang, Bin;Chen, Yixue
    • Nuclear Engineering and Technology
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    • v.52 no.6
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    • pp.1137-1147
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    • 2020
  • The discrete ordinates method (SN) is one of the major shielding calculation method, which is suitable for solving deep-penetration transport problems. Our objective is to explore the available quadrature sets and to improve the accuracy in shielding problems involving strong anisotropy. The linear discontinuous finite-element (LDFE) quadrature sets based on the icosahedron (in short, ICLDFE quadrature sets) are developed by defining projected points on the surfaces of the icosahedron. Weights are then introduced in the integration of the discontinuous finite-element basis functions in the relevant angular regions. The multivariate secant method is used to optimize the discrete directions and their corresponding weights. The numerical integration of polynomials in the direction cosines and the Kobayashi benchmark are used to analyze and verify the properties of these new quadrature sets. Results show that the ICLDFE quadrature sets can exactly integrate the zero-order and first-order of the spherical harmonic functions over one-twentieth of the spherical surface. As for the Kobayashi benchmark problem, the maximum relative error between the fifth-order ICLDFE quadrature sets and references is only -0.55%. The ICLDFE quadrature sets provide better integration precision of the spherical harmonic functions in local discrete angle domains and higher accuracy for simple shielding problems.

Wavenumber Correlation Analysis of Statellite Geopotential Anomalies

  • Kim, Jeong-Woo;Kim, Won-Kyun;Kim, Hye-Yun
    • Economic and Environmental Geology
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    • v.33 no.2
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    • pp.111-116
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    • 2000
  • Indentifying anomaly correlations between data sets is the basis for rationalizig geopotential interpretation and theory. A procedure is presented that constitutes an effective process for identifying correlative features between the two or more geopotential data sets. Anomaly features that show direct, inverse, or no correlations between the data may be separated by applying filters in the frequency domains of the data sets. The correlation filter passes or rejects wavenumbers between co-registered data sets based on the correlation coefficient between common wavenumbers as given by the cosine of their phase difference. This study includes an example of Magsat magnetic anomaly profile that illustrates the usefulness of the procedure for extracting correlative features between the data sets.

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Wavenumber correlation analysis of satellite magnetometer observations

  • Kim, Jeong-Woo;Kim, Won-Kyun;Kim, Hye-Yun
    • Proceedings of the KSEEG Conference
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    • 2000.04b
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    • pp.311-313
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    • 2000
  • Identifying anomaly correlations between data sets is the basis for rationalizing geopotenial interpretation and theory. A procedure between the two or more geopotential data sets. Anomaly features that show direct, inverse, or no correlationsbetween the data may be separated by applying filters in the frequency domains of the data sets. The correlation filter passes or rejects wavenumbers between co-registered data sets based on the correlation coefficient between common wavenumbers as given by the cosine of their phase difference. This study includes as example of Magsat magnetic anomaly profile that illustrates the usefulness of the procedure for extracting correlative features between the sets.

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AGV Navigation Using a Space and Time Sensor Fusion of an Active Camera

  • Jin, Tae-Seok;Lee, Bong-Ki;Lee, Jang-Myung
    • Journal of Navigation and Port Research
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    • v.27 no.3
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    • pp.273-282
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    • 2003
  • This paper proposes a sensor-fusion technique where rho data sets for the previous moments are properly transformed and fused into the current data sets to enable accurate measurement, such as, distance to an obstacle and location of the service robot itself. In the conventional fusion schemes, the measurement is dependent only on the current data sets. As the results, more of sensors are required to measure a certain physical promoter or to improve the accuracy of the measurement. However, in this approach, intend of adding more sensors to the system, the temporal sequence of the data sets are stored and utilized for the measurement improvement. Theoretical basis is illustrated by examples md the effectiveness is proved through the simulation. Finally, the new space and time sensor fusion (STSF) scheme is applied to the control of a mobile robot in the indoor environment and the performance was demonstrated by the real experiments.

A Study on Mobile Robot Navigation Using a New Sensor Fusion

  • Tack, Han-Ho;Jin, Tae-Seok;Lee, Sang-Bae
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2003.09a
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    • pp.471-475
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    • 2003
  • This paper proposes a sensor-fusion technique where the data sets for the previous moments are properly transformed and fused into the current data sets to enable accurate measurement, such as, distance to an obstacle and location of the service robot itself. In the conventional fusion schemes, the measurement is dependent on the current data sets. As the results, more of sensors are required to measure a certain physical parameter or to improve the accuracy of the measurement. However, in this approach, instead of adding more sensors to the system, the temporal sequence of the data sets are stored and utilized for the measurement improvement. Theoretical basis is illustrated by examples and the effectiveness is proved through the simulations. Finally, the new space and time sensor fusion (STSF) scheme is applied to the control of a mobile robot in an unstructured environment as well as structured environment.

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Control of the Mobile Robot Navigation Using a New Time Sensor Fusion

  • Tack, Han-Ho;Kim, Chang-Geun;Kim, Myeong-Kyu
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.4 no.1
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    • pp.23-28
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    • 2004
  • This paper proposes a sensor-fusion technique where the data sets for the previous moments are properly transformed and fused into the current data sets to enable accurate measurement, such as, distance to an obstacle and location of the service robot itself. In the conventional fusion schemes, the measurement is dependent on the current data sets. As the results, more of sensors are required to measure a certain physical parameter or to improve the accuracy of the measurement. However, in this approach, instead of adding more sensors to the system, the temporal sequence of the data sets are stored and utilized for the measurement improvement. Theoretical basis is illustrated by examples and the effectiveness is proved through the simulations. Finally, the new space and time sensor fusion(STSF) scheme is applied to the control of a mobile robot in an unstructured environment as well as structured environment.

A Study on Indoor Mobile Robot Navigation Used Space and Time Sensor Fusion

  • Jin, Tae-Seok;Ko, Jae-Pyung;Lee, Jang-Myung
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.104.2-104
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    • 2002
  • This paper proposes a sensor-fusion technique where the data sets for the previous moments are properly transformed and fused into the current data sets to enable accurate measurement, such as, distance to an obstacle and location of the service robot itself. In the conventional fusion schemes, the measurement is dependent on the current data sets. As the results, more of sensors are required to measure a certain physical parameter or to improve the accuracy of the measurement. However, in this approach, instead of adding more sensors to the system , the temporal sequence of the data sets are stored and utilized for the measurement improvement. Theoretical basis is il lustrated by examples and...

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Features Extraction of Remote Sensed Multispectral Image Data Using Rough Sets Theory (Rough 집합 이론을 이용한 원격 탐사 다중 분광 이미지 데이터의 특징 추출)

  • 원성현;정환묵
    • Journal of the Korean Institute of Intelligent Systems
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    • v.8 no.3
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    • pp.16-25
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    • 1998
  • In this paper, we propose features extraction method using Rough sets theory for efficient data classifications in hyperspectral environment. First, analyze the properties of multispectral image data, then select the most efficient bands using discemibility of Rough sets theory based on analysis results. The proposed method is applied Landsat TM image data, from this, we verify the equivalence of traditional bands selection method by band features and bands selection method using Rough sets theory that pmposed in this paper. Finally, we present theoretical basis to features extraction in hyperspectral environment.

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