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1.
This paper describes packages for symbolic calculations in quantum groups, noncommutative differential geometry, and multivalued logic. The package for quantum groups and the program for logic are written in Mathematica 3.0 and/or 4.0. As an example, some results in the logic obtained using these packages are presented.  相似文献   

2.
We present a software module which allows one to efficiently perform molecular dynamics and local minimization calculations in internal coordinates when incorporated into a molecular dynamics package. We have implemented a reference interface to the NIH version of the X-PLOR structure refinement package and we show that the module provides superior torsion-angle dynamics functionality relative to the native X-PLOR implementation. The module has been designed in a portable fashion so that interfacing it with other packages should be relatively easy. Other features of the module include the ability to define rather general internal coordinates, an accurate integration algorithm which can automatically adjust the integration step size, and a modular design, which facilitates extending and enhancing the module.  相似文献   

3.
Modules and packages for the one-loop calculations at the partonic level represent the first level of SANC output computer product. The next level represents Monte Carlo integrator mcsanc, realizing fully differential hadron level calculations (convolution with PDF) for the HEP processes at LHC. In this paper we describe the implementation into the framework mcsanc first set of processes: DY NC, DY CC, $f_1 \bar f'_1 \to HW^ \pm (Z)$ and single top production. Both EW and QCD NLO corrections are taken into account. A comparison of SANC results with those existing in the world literature is given.  相似文献   

4.
简要介绍了中国承担设计和制造任务的ITER 计划采购包的构成情况,分析了ITER 采购包采用标准的原则和ITER 中国采购包引用标准的特点,总结了ITER 中国采购包标准化现状。基于当前ITER 中国采购包对标准的需求以及着眼于国内磁约束核聚变长远发展需要,讨论提出了当前ITER 中国采购包的标准化策略建议。  相似文献   

5.
简要介绍了中国承担设计和制造任务的ITER计划采购包的构成情况,分析了ITER采购包采用标准的原则和ITER中国采购包引用标准的特点,总结了ITER中国采购包标准化现状。基于当前ITER中国采购包对标准的需求以及着眼于国内磁约束核聚变长远发展需要,讨论提出了当前ITER中国采购包的标准化策略建议。  相似文献   

6.
In the framework of density functional theory, the structural, electronic and lattice dynamical properties of platinum pernitride have been investigated using the plane wave pseudopotential within the GGA and LDA functional for treating the effects of exchange correlation implemented in PWSCF and ABINIT packages. The computed lattice constant and bulk modulus agree well with the experiment and other theoretical calculations. Both packages and correlation functional agree well on the lattice constant within the deviation of about 1.6%. The bulk modulus has been quite successfully predicted by LDA. The electronic structure and DOS of platinum pernitride show a narrow gap and confirms semiconducting nature of this compound. The lattice dynamical calculation shows that the platinum nitride in pyrite structure (platinum pernitride) is dynamically stable. The zone center phonon frequencies particularly the Raman active phonons agree well with the experimental Raman data in the case of GGA implemented in PWSCF. The pressure variation of Raman active modes shows a linear variation; however, at higher pressure the variation is fast.  相似文献   

7.
Detector packages consisting of plastic nuclear track detectors, nuclear emissions, and thermoluminescence detectors were exposed inside BIORACK during the Spacelab missions IML1 and IML2, in different sections of the MIR space station, and inside the Spacelab module at rack front panels or stowage lockers and in the Spacelab tunnel during D2. In addition, during D2, each Payload Specialist (PS) has worn three permanent detector packages; one at the neck; one at the waist; and one at the ankle. Total dose measurements, particle fluence rate and LET spectra, number of nuclear disintegrations and neutron dose from this exposure are given in this report. The results are compared to theoretical calculations and to previous missions results. The dose equivalent (total radiation exposure) received by the PSs were calculated from the measurements and range from 190 to 770 μSv d−1. Finally, a cursory investigation of results from a particle telescope from two silicon detectors, first used in the last BIORACK mission on STS76, is reported.  相似文献   

8.
In this paper we describe the implementation of the charged current decays of the type t→bl+νl(γ) in the framework of the SANC system. All calculations are done taking into account the one-loop electroweak correction in the standard model. The emphasis of this paper is on the presentation of numerical results. Various distributions are produced by means of a Monte Carlo integrator and event generator. Comparison with the results of the CompHEP and PYTHIA packages are presented for the Born and hard photon contributions. The validity of the cascade approximation at one-loop level is also studied. PACS 14.65.Ha; 12.15.-y; 12.15.Lk  相似文献   

9.
Compact quasi-optics are difficult to design with any confidence using techniques developed for visible wavelengths. In this paper we investigate the performance of existing software design tools (ASAP, CODE V, GLAD) as well as a Gaussian beam mode analysis technique not yet available as commercial software. We have devised a set of test cases and used these to study the underlying methodologies and physics of these packages and we probe their suitability for the analysis of submillimetre-wave systems and components. We have used the physical optics package GRASP as our benchmark software.  相似文献   

10.
李文亮  张季  姚洪斌 《物理学报》2013,62(12):123202-123202
多组态含时Hartree Fock 理论方法作为一种研究强激光场中多电子原子分子体系动力学行为的一种有效手段, 近几年来备受关注. 本文介绍了该方法的发展历史, 重点介绍了本研究组近几年来对该理论方法的发展, 以及多组态含时Hartree Fock理论方法在原子基函数表象、 格点表象、 二次量子化表象不同的实现方案, 并就典型体系做了大量详细的计算. 同时也详细介绍了该方法在实际应用中存在的挑战, 展望了多组态含时Hartree Fock理论方法的发展应用前景. 关键词: 强激光场 多电子动力学 电子相关  相似文献   

11.
The title problem is solved by using a conformal mapping-variational method. The calculated eigenvalues are in good agreement with those obtained by using a finite element approach. The problem is of practical importance since the knowledge of the dynamic behavior of odd-shaped plates is of great interest in the design of electronic packages containing printed circuit boards.  相似文献   

12.
利用基于多组态Dirac-Fock方法的程序包GRASP92和RATIP以及在此基础上最新发展的RERR06程序,计算了锂原子1s2nl(n=2,3; l=s, p) 的内壳层和外壳层的光电离截面. 计算中详细考虑了光电离过程中的弛豫效应. 结果表明:在锂原子内壳层电子的光电离过程中弛豫效应较强,而在外壳层电子的光电离过程中弛豫效应较弱. 另外,相应于不同态的内壳层光电离过程,其弛豫效应的影响也不同,对激发态的影响比对基态的影响大,对高激发态 关键词: 多组态Dirac-Fock方法 光电离截面 弛豫效应  相似文献   

13.
Recently, 3-D Digital Image Correlation (DIC) is widely applied to the reliability analysis of electronic packages, which particularly characterizes the in-situ deformation of ball grid array (BGA) packages. During the image correlation procedure, many parameters influence the accuracy and data integrity of measurement result. Facet (subset) size is the principal parameter and has been studied with much effort. However, the solder balls, which are built on the substrate surface, make the scenario different with the conventional 3-D DIC experiment for the planar samples. The undulant surface generates more obstacles for the successful image correlation. In order to summarize an effective solution of 3-D DIC measurement method for solder balls attached packages, camera angle, facet size and facet step are studied with different BGA packages and different stereoscopic camera systems to achieve the best correlation quality. Also, a novel surface treatment method is introduced to guarantee the surface speckles are generated uniformly on the fluctuant surface.  相似文献   

14.
Jun Kang 《中国物理 B》2022,31(10):107105-107105
The growing worldwide energy needs call for developing novel materials for energy applications. Ab initio density functional theory (DFT) calculations allow the understanding and prediction of material properties at the atomic scale, thus, play an important role in energy materials design. Due to the fast progress of computer power and development of calculation methodologies, DFT-based calculations have greatly improved their predictive power, and are now leading to a paradigm shift towards theory-driven materials design. The aim of this perspective is to introduce the advances in DFT calculations which accelerate energy materials design. We first present state-of-the-art DFT methods for accurate simulation of various key properties of energy materials. Then we show examples of how these advances lead to the discovery of new energy materials for photovoltaic, photocatalytic, thermoelectric, and battery applications. The challenges and future research directions in computational design of energy materials are highlighted at the end.  相似文献   

15.
The laser-welded coaxial-type laser module packages using an on-line monitoring system (OLMS) is presented. The OLMS is integrated with an ultra high precision laser displacement meter (LDM) and a laser welding system that enables to quantitatively on-line process the successive postweld shift (PWS) measurements by the LDM and corrections by the laser welding during multiple welding compensations in laser-welded laser module packages. The results show that the high-yield laser module packages with high coupling efficiency of 86-97% are obtained. The fiber shifts due to the PWS could be realigned back closer to their original position after applying multiple welding compensations, and hence the coupling powers loss due to the PWS could be recovered. This OLMS study has provided a practical package guideline for fabricating reliable laser module packages with high yield and high coupling efficiency for use in low-cost lightwave transmission systems.  相似文献   

16.

Argon has been widely used as a diluent for high-temperature reacting flow experiments. Numerical simulation of such process requires accurate diffusion coefficients for the H–Ar pair. All available potential energy functions for the H–Ar system have been empirically extrapolated in the repulsive region and are probably not reliable for prediction of H–Ar binary diffusion coefficient at high temperatures. We perform calculations using the restricted coupled cluster theory with single and double excitation (plus triple corrections) [RCCSD(T)] and suitable basis sets to obtain accurate potential energies. The calculated potential energy function is corrected for basis set superposition error and is validated against molecular beam scattering data. Comparisons with previous literature potential functions are also made. Using the Chapman–Enskog theory we carried out first-principle calculation of high-temperature diffusion coefficients by direct numerical integration of the collision integrals using the RCCSD(T) potential function. The computed diffusion coefficients are validated against available experimental data. Comparisons are also made with results obtained from transport compilations and packages commonly used in combustion simulation.  相似文献   

17.
张学亮  金锋  高福斌  张平 《光学学报》2000,20(11):504-1508
对于聚合物电光波导,依据理想光波导耦合理论的微扰理论,推导传播常数和损耗系数的近似表达式,从而将求解本征值的复杂复数运算简化成简单实数运算。数值计算表明,这些近似解与正确解很好相符。给出的近似公式和特征曲线可供聚合物电光波导及其器件的设计和制备作参考。  相似文献   

18.
Computations of the accelerator section of the International Linear Collider (ILC), which consists of superconducting niobium cavities, are performed for conditions of the maximum energy transfer to electrons that travel along the cavity axis. A mathematical model and software packages are created for the computation of the electric characteristics and profile of a single-cell cavity. A computer-based synthesis of the cavity shape that yields the required electric characteristics is performed. The promising design variants of a single-cell cavity, with which a quality factor of 1010 is provided at a working frequency of 1.3 GHz, are found to optimize the construction and manufacture of a single-cell cavity. The electric characteristics of a chain of single-cell cavities are computed.  相似文献   

19.
叙述了Moyer模式在高能重离子加速器屏蔽设计中的应用.介绍了Moyer参数的选择,给出了束流的点源损失和无限或有限均匀线源损失的屏蔽计算方法.给出了根据天空反照剂量限值估算屋顶屏蔽厚度的方法.计算结果与Monte Carlo方法进行了比较.  相似文献   

20.
张为权 《光子学报》2005,34(7):1090-1093
建立了折射光线轨迹的软件包和提出了波象差的计算方法.利用这个软件包,分析了双焦透镜的各类象差和象差与入射角的关系.这个软件包的特点是各种物理量的计算十分清晰,它为改进晶体元件的设计提供了理论依据.  相似文献   

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