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131.
教师课堂教学质量的多元统计分析 总被引:3,自引:0,他引:3
应用多元统计分析中的聚类分析法和主成分分析法对教师高等数学的课堂教学质量进行了统计分析,通过对数据的聚类分析结果提出教师应注重启发性教学并善于引导学生解决实际问题.同时利用主成分分析将原先众多的评价指标用三个指标代替,为进一步提高教学质量提供科学的依据. 相似文献
132.
应用物理类专业电磁学课程教学内容改革 总被引:2,自引:0,他引:2
应用物理类专业的培养目标是培养物理学应用型人才,物理学应用型人才是具备实验物理学家和工程师双重素质的复合型人才,物理学应用型人才应着重技术创新和应用能力的培养,应编写区别于物理学专业的、适应应用物理类专业特点的课程教材,应用物理类专业《电磁学》教材遵循电磁理论发展顺序的体系能体现理论发展的规律,符合普通物理的特点、要求和教学目标,文章论述了应用物理类专业课程教学内容改革的指导思想,介绍了我国第一套适应应用物理专业的面向21世纪的《电磁学》教材的特点。 相似文献
133.
134.
Michael Devereux 《Foundations of Physics Letters》2003,16(1):41-55
Using an isolated measurement process, we calculate the effect measurement has on entropy for the multi-cylinder Szilard engine. We find that the system of cylinders possesses an entropy associated with cylinder total energy states, and that it records information transferred at measurement. Contrary to other's results, we find that the apparatus loses entropy due to measurement. The Second Law of Thermodynamics may be preserved if Maxwell's demon gains entropy moving the engine partition. 相似文献
135.
Marco Merkli 《Journal of Mathematical Analysis and Applications》2007,327(1):376-399
Level shift operators describe the second-order displacement of eigenvalues under perturbation. They play a central role in resonance theory and ergodic theory of open quantum systems at positive temperatures. We exhibit intrinsic properties of level shift operators, properties which stem from the structure of open quantum systems at positive temperatures and which are common to all such systems. They determine the geometry of resonances bifurcating from eigenvalues of positive temperature Hamiltonians and they relate the Gibbs state, the kernel of level shift operators, and zero energy resonances. We show that degeneracy of energy levels of the small part of the open quantum system causes the Fermi Golden Rule Condition to be violated and we analyze ergodic properties of such systems. 相似文献
136.
R. Carroll 《Theoretical and Mathematical Physics》2007,152(1):904-914
Quantization using quantum potentials is described in terms of momentum fluctuations, and it is related to Fisher information
and entropy.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 1, pp. 32–44, July, 2007. 相似文献
137.
We have investigated the effects of the magnetic field which is directed perpendicular to the well on the binding energy of the hydrogenic impurities in an inverse parabolic quantum well (IPQW) with different widths as well as different Al concentrations at the well center. The Al concentration at the barriers was always xmax=0.3. The calculations were performed within the effective mass approximation, using a variational method. We observe that IPQW structure turns into parabolic quantum well with the inversion effect of the magnetic field and donor impurity binding energy in IPQW strongly depends on the magnetic field, Al concentration at the well center and well dimensions. 相似文献
138.
Quantum Key Distribution Using Four-Qubit W State 总被引:3,自引:0,他引:3
CAO Hai-Jing SONG He-Shan 《理论物理通讯》2006,46(1):65-68
A new theoretical quantum key distribution scheme based on entanglement swapping is proposed, where four-qubit symmetric W state functions as quantum channel. It is shown that two legitimate users can secretly share a series of key bits by using Bell-state measurements and classical communication. 相似文献
139.
Munshi G. Mustafa 《Pramana》2006,66(4):669-687
We briefly introduce the thermal field theory within imaginary time formalism, the hard thermal loop perturbation theory and
some of its applications to the physics of the quark-gluon plasma, possibly created in relativistic heavy-ion collisions 相似文献
140.
We study GaN/AlN Quantum Dot (QD) superlattices utilizing the STREL environment which allows the building of atomistic models, relaxation of the structures, the calculation of the electronic states and optical transitions and the visualization of the results. The forces are calculated using an appropriate Keating or Stillinger–Weber interatomic potential model and the electronic states and optical transitions using a tight-binding formulation which is economical and produces realistic electronic properties. The relaxed structure has strains mainly in the GaN region which are compressive and small tensile strains in the AlN region, mainly below the QD. In the calculation of the electronic states and of the optical transitions the strains are included realistically at the atomistic level. The study of the wavefunctions close to the fundamental gap show how these strains influence the form and spatial extent of the wavefunction. Very close to the fundamental gap the valence and some conduction states are confined in the QD and have considerable oscillator strength. 相似文献