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921.
We study non-skewselfadjoint representations of a finite dimensional real Lie algebra . To this end we embed a non-skewselfadjoint representation of into a more complicated structure, that we call a -operator vessel and that is associated to an overdetermined linear conservative input/state/output system on the corresponding simply connected Lie group . We develop the frequency domain theory of the system in terms of representations of , and introduce the joint characteristic function of a -operator vessel which is the analogue of the classical notion of the characteristic function of a single non-selfadjoint operator. As the first non-commutative example, we apply the theory to the Lie algebra of the group, the group of affine transformations of the line. 相似文献
922.
923.
Optical windows with external surfaces shaped to satisfy operational environment needs are known as special windows. A novel special window, a sphere-cone-polynomial (SCP) window, is proposed. The formulas of this window shape are given. An SCP MgF2 window with a fineness ratio of 1.33 is designed as an example. The field-of-regard (FOR) angle is ±75°. From the window system simulation results obtained with the calculated fluid dynamics (CFD) and optical design software, we find that compared to the conventional window forms, the SCP shape can not only introduce relatively less drag in the airflow, but also have the minimal effect on imaging. So the SCP window optical system can achieve a high image quality across a super wide FOR without adding extra aberration correctors. The tolerance analysis results show that the optical performance can be maintained with a reasonable fabricating tolerance to manufacturing errors. 相似文献
924.
925.
926.
This tutorial provides a concise overview of support vector machines and different closely related techniques for pattern classification. The tutorial starts with the formulation of support vector machines for classification. The method of least squares support vector machines is explained. Approaches to retrieve a probabilistic interpretation are covered and it is explained how the binary classification techniques can be extended to multi-class methods. Kernel logistic regression, which is closely related to iteratively weighted least squares support vector machines, is discussed. Different practical aspects of these methods are addressed: the issue of feature selection, parameter tuning, unbalanced data sets, model evaluation and statistical comparison. The different concepts are illustrated on three real-life applications in the field of metabolomics, genetics and proteomics. 相似文献
927.
Based on the classical turning point of electron movement in a molecule, a model for defining the molecular characteristic boundary contour is advanced. By using an accurate ab initio MELD program and an auxiliary program, some electron parameters in a molecule, such as the potential felt by an electron, have been evaluated. According to our model and definition, the molecular characteristic contour of the equilibrium geometry configuration is drawn and a vivid intuitive picture for describing the forming or breaking of a chemical bond is displayed. 相似文献
928.
The purpose of this paper is to study the magnetomechanical characteristic of a microsensor which is composed of a cantilevered
beam-plate with ferromagnetic films in order to measure the magnetic field from the deformation of plate when the microsensor
is located in the magnetic field. To this end, a numerical approach made up of the finite element method for magnetic field
and the finite difference method for deflection of the microsensor is proposed to perform the numerical analysis of deflection
under magnetoelastic interaction. Some quantitative results of a case study for the magnetoelastic characteristic between
the magnetic field and deflection of the microsensor in the magnetic field are given. The results show that this microsensor
can be used not only to measure the magnitude of magnetic intensity, but also to possibly monitor the direction of the vector
of the magnetic field.
The project supported by the NNSFC(No. 19772014), the China National Foundation for Outstanding Young Researchers(No. 19725207),
and Foundation for University Key Teacher by the Ministry of Education of China. 相似文献
929.
Shimin Wang·Jieqiong Xu·Qi Wang Division of General Mechanics Beihang University Beijing China 《Acta Mechanica Sinica》2010,26(3):441-448
The phase characteristic of a disk rubbing with a ring supported elastically is investigated and used to explain the mechanism of stiffness increase phenomenon. As long as the rubbing is maintained, the averaged phase difference between the disk and the rotating mass on the disk is defi- nitely less than π/2. When the rubbing finishes, the phase difference quickly approaches to 7r. This behavior is inde- pendent of the physics parameters of the rubbing system. The theoretical results are qualitatively verified with experiments. 相似文献
930.
The oxidation of metal sulphides and sulphide concentrates was studied by means of DTA, TG and DTG curves. The behaviour of
ZnS, CdS, GaS, Tl2S, Sb2S3 and Sb2S5 during thermal treatment in an oxidizing medium was investigated. The properties of these sulphides were compared and conclusions
were drawn about their probable oxidation reactions and the kind of end-products obtained. The characteristic temperatures
of the studied sulphides were determined on the basis of curves (DTA). The values obtained were used to compare the behaviour
of the sulphides during the oxidation process in a fluid bed. The results can be used to improve the technological and economic
indices in the industrial production of zinc.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献