中学生数学观的现状及形成探究

本文指出中学数学观的意义。根据对中、美两国中学生数学观的调查和比较,以及对我国中学生数学观的补充调查,概括当前中学生教学观的某些现状,进而探讨数学现形成与数学教育的相关性。为数学教育改革提供依据。

现代小学数学实践教学研究与探讨

教材并不是培养当今社会所需人才的圣经、宝典。我们要从把教材内容从枯燥无味转化为富有情趣、把书本数学转化为生活数学、把学生由简单的操作工转化为知识的探究者、把计算方法统一化转化为计算方法多样化等几个方面对教材进行合理、灵活的利用,使自己成为教材的积极实践者和创建者!

当前数学多媒体课件制作的四个误区

随着现代化教学手段的发展和普及,多媒体课件的制作将成为数学教师备课和研究的一个基本内容,多媒体课件在数学课堂上的运用也必将越来越广泛。于是,如何遵循数学教学的规律,充分发挥现代化教学手段的作用,真正使现代化教学手段为数学教学现代化服务,便成为一个极为重要的研究课题。从我们接触的一些课件和课堂操作看,使用效果理想的并不很多,许多课件存在明显的不足,有许多方面的误区。

Charmonium Spectrum and Their Transitions in Relativistic Quark Models

Using the phenomenological relativistic harmonic model （RHM） for quarks, we have obtained the masses of S wave charmonium states. The full Hamiltonian used in the investigation has Lorentz scalar plus vector confinement potential, along with the confined one gluon exchange potential （COGEP）. A good agreement with the experimental masses for the ground state and the radially excited states is obtained for both the triplet and singlet S wave mesons. The calculated charge radii, meson decay constants, leptonic decay width, two photon decay width, and the radiative M1 decay width are in good agreement with the experimental results.

远离教学误区 提高教学效益——关于当前数学教学现状的几点思考

随着高中数学新课程标准的颁布与实施,新理念、新方法登堂入室,与课堂教学紧密结合,赋予新课标以生命力.然而由于课堂教学实践的丰富性和复杂性。

Mathematical analysis of physicochemical phenomena in the catalyst during hydrogenating depolymerization of coal extract benzene insoluble fraction

Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co–Mo/Al2O3 catalyst were assessed using a mathematical model. The analytical equations of the mathematical model were generated based on material balance incorporating the physico-chemical phenomena(reaction and diffusion) both in the autoclave and the catalyst grain. The equations offer the possibility for predicting changes of the reactants in the autoclave during the process and for determining the distribution of reactant concentrations in the grain as a function of its radius. The analytical equations of the model serve as the basis of the algorithm for assessing the influence of restrictive diffusion on the effectiveness and selectivity of the catalyst, and also for defining the optimal radii of the catalyst's pores to enable free transport of reactants in the grain interior.

Spinor Field Realizations of Non-critical W2,4 String Based on Linear WI,2,4 Algebra

In this paper, we investigate the spinor field realizations of the W2,4 algebra, making use of the fact that the W2,4 algebra can be linearized through the addition of a spin-1 current. And then the nilpotent BRST charges of the spinor non-critical W2,4 string were built with these realizations.

Retrieval of inherent optical properties of the Yellow Sea and East China Sea using a quasi-analytical algorithm

We tested and modified the quasi-analytical algorithm （QAA） using 57 groups of field data collected in the spring of 2003 in the Yellow Sea and East China Sea. The QAA performs well in deriving total absorption coefficients of typical coastal waters. The average percentage difference （APD） is in a range of 13.9%-38.5% for the total absorption coefficient （13.9% at 440 nm）, and differences in particle backscattering coefficient bbp（2） are less than 50% （in the case of the updated QAA）. To obtain improved results, we modified the QAA by adjusting the empirical relationships. The modified algorithm is then applied to the field data to test its performance. The APDs were 44.7%-46.6% for bbp（λ） and 9.9%-32.8% （9.9% at 555 nm） for the total absorption coefficient. This indicates that the modified QAA derives better results. We also used the modified model to derive phytoplankton pigment absorption （aph） and detritus and CDOM absorption （aug） coefficients. The APDs for aph and a dg at 440 nm are 37.1% and 19.8%. In this paper, we discuss error sources using the measured dataset. More independent field data can improve this algorithm and derive better results.

ELASTIC DEFORMATION ANALYSIS OF MULTILA YERED STRANDS

This paper describes a general model for the mechanical behavior studying of general wire rope strand. An exact solution of the deformation characteristics was given when the strands is under tensile and torsional loads. The theoretical results are useful in evaluating the extensional and torsional moduli of rigidity for the strands. Finally, a simple design criterion is establised for the nonrotating ropes.

Gastrointestinal stromal tumors:Thirty years experience of an Institution

AIM:To report our experience of gastrointestinal stromal tumors (GISTs) during the last 29 years. METHODS:Thirty two cases of GIST referred to our Institution from the 1st January 1981 to the 10th June 2010 were reviewed. Metastases,recurrence and survival data were collected in relation to age,history,clinical presentation,location,size,resection margins and cellular features. RESULTS:Mean age was 63.7 years (range,40-90) and incidence was slightly higher in males (56%). R0 resection was performed in 90.7% of cases,R1 in 6.2% (2 cases) and R2 in 3.1% (one case). Using Fletcher's classification 8/32 (25%) had high risk,9/32 (28%) intermediate and 15/32 (47%) low risk tumors. Follow-up varied from 1 mo to 29 years,with a median of 8 years; overall survival was 75% (24/32),disease-free survival was 72% and tumor-related mortality was 9.3%. Three patients with high risk GIST were treated with imatinib mesylate:one developed a recurrence after 36 mo,and 2 are free from disease at 41 mo. CONCLUSION:Surgical treatment remains the gold standard therapy for resectable GISTs. Pathological and biological features of the neoplasm represent the most important factors predicting the prognosis.

Is Using Mathematics and Game Theory in Analyzing Economic Phenomena Scientific？

In the article, the author presents some arguments concerning the ＂mathematical method issue＂ in modem economics. The author shows why some reasons, according to which we should use mathematics in （economic） theory, are not convincing （they are even tautological）, and what does mathematization have to do with arbitrariness of the orthodox economic theory. The author also shows why using game theory （a mathematical discipline） in modem microeconomics does not yield knowledge and correct explanation of economic situations and phenomena. At the end, the author presents fundamental questions that form the basis of economic science and its qualitative research methods, and shows what their practical relevance is. The purpose of this article is to argue, contrary to common opinion, that there can be an exact and objective science of economic phenomena that does not necessarily use modem mathematical theories or methods to explain these phenomena.

Field tests on mechanical characteristics and strength parameters of red-sandstone

Large-scale field shear tests on ten specimens of the red-sandstone embankment at a highway in Hunan,China,were performed to examine mechanical characteristics and parameters of red-sandstone.The curves of thrust-displacement,failure mode,and shear strength parameters for red-sandstone with different water contents,different compactions,and different grain size distributions were obtained from the tests.A practical procedure of in-situ test for red-sandstone embankment was proposed to normalize the test equipment and test steps.Based on three-dimensional thrust-sliding limit equilibrium method,the formulas for calculating strength parameters of red-sandstone considering three-dimensional sliding surface were inferred.The results show that red-sandstone has typical complete curves of stress-strain,strain softening,which are caused by the special structure of red-sandstone;water content and compaction are important factors for strength and failure mode of red-sandstone;The average value of cohesion and internal friction angle of the specimens calculated by three-dimensional technique are 21.56 kPa and 29.29°,respectively,and those by traditional two-dimensional method are 25.52 kPa and 33.76°,respectively.

Mass Transfer During Osmotic Dehydration Using Acoustic Cavitation

An experimental study on intensifying osmotic dehydration was carried out ina state of nature and with acoustic cavitation of different cavitating intensity (0.5A, 0.7A and0.9A) respectively, in which the material is apple slice of 5mm thickness. The result showed thatacoustic cavitation remarkably enhanced the osmotic dehydration, and the water loss was acceleratedwith the increase of cavitating intensity. The water diffusivity coefficients ranged from1.8x10^(-10)m^2·s^(-1) at 0.5A to 2.6x10^(-10)m^2·s^(-1) at 0.9A, and solute diffusivitycoefficients ranged from 3.5x10^(-11) m^2·s^(-1) at 0.5A to 4.6X10^(-11)m^2·s^(-1) at 0.9A. On thebasis of experiments, a mathematical model was established about mass transfer during osmoticdehydration, and the numerical simulation was carried out. The calculated results agree well withexperimental data, and represent the rule of mass transfer during osmotic dehydration intensified byacoustic cavitation.

Mathematical Modelling of Cutting Force as the Most Reliable Information Bearer on Cutting Tools Wearing Phenomenon

Being one of their prominent exploitative characteristics, cutting tools durability depends on the character, intensity and the speed of wearing. Identification of tool wearing is of great significance for the purpose of avoiding sooner or later replacement of tools. The parameters of tool wearing can be measured by out-process and in-process-measuring systems. Given the extremely limiting role of the former in modern production lines, development of the latter （the indirect measuring systems） has gained prominence, The basis of indirect measuring systems comprises a set of various signals originating from the units of the system under treatment which stand in certain correlations with the wearing parameters. The paper presents mathematical models of axial force designed on the basis of experimental research in drilling tempered steel by twist drills made of high-speed steel manufactured by powder metallurgy.

Painleve Analysis and Determinant Solutions of a (3+1)-Dimensional Variable-Coefficient Kadomtsev-Petviashvili Equation in Wronskian and Grammian Form

In this paper, the investigation is focused on a （3＋1）-dimensional variable-coefficient Kadomtsev- Petviashvili （vcKP） equation, which can describe the realistic nonlinear phenomena in the fluid dynamics and plasma in three spatial dimensions. In order to study the integrability property of such an equation, the Painlevé analysis is performed on it. And then, based on the truncated Painlevé expansion, the bilinear form of the （3＋1）-dimensionaJ vcKP equation is obtained under certain coefficients constraint, and its solution in the Wronskian determinant form is constructed and verified by virtue of the Wronskian technique. Besides the Wronskian determinant solution, it is shown that the （3＋1）-dimensional vcKP equation also possesses a solution in the form of the Grammian determinant.

Hamilton Number Neural Network Model

The stability and the sequential dynamics of the sixteen-state Hamiltnn neural network model have been discussed with the energy function. The optical implementation scheme about Hamilton number vector-matrix multiplication is simply discussed.

How Hermann Weyl Could Deal with Paul Benacerraf＇s （1973） Challenge to Realism？

Christopoulou Demetra（In his work, Hermann Weyl （1926） addresses the issue of abstraction principles, an issue that has been broadly discussed during the last decades with regard to the Neo-Fregean program. This paper aims to show off the way Weyl＇s account of abstraction could offer a reply to Benacerraf＇s （1973） challenge to realism. Benacerraf argued that mathematical realism is not associated with a plausible epistemology about human access to abstract objects. Weyl deals with the method of abstraction by investigating certain cases of Fregean abstraction principles. He thinks that we can introduce shapes of geometrical images, integers mod m, circles, directions of lines etc. by means of certain creative acts of consciousness, especially intentionality towards proper relations between the elements of an initial domain. Weyl puts emphasis on intentions towards certain invariant characteristics of items that are involved in equivalence relations. Further, he claims that those invariants are transformed into ideal objects through a finite process that is involved in intuition. This paper, in the first place, attempts to make explicit Weyl＇s phenomenological leanings. Secondly, it argues that Weyl＇s explanation of how ideal mathematical objects become present to mind can address the epistemic issue concerning mathematical knowledge and can also be associated with a particular view which is implicit in his philosophy and retains realistic elements. Hence, it can address Benacerraf＇s problem.

Research for Using Information Technology in the Design of Effective Mathematics Teaching Methods

The development of modem information technology has brought unprecedented impact on mathematics teaching, which affects the content of the curriculum, and teaching and its manifestations, affecting the role of teachers in the teaching process and its relationship with the students, teaching methods and impacting policies the selection and use, affecting organizational form of teaching. Mathematics curriculum standards clearly stated： the design and implementation of the mathematics curriculum should pay attention to the use of modern information technology, particularly to fully consider the impact on mathematics learning content and methods, and to provide students with a more vigorous development of rich learning resources, the modem information technology as a powerful tool for students to learn math and problem-solving, working to change the way students learn, students willing and more energy into reality, exploratory math activities.

Vibrational Structure of Selected Compounds Derived from Biomass： Lignin Dimers, Selected Aldopentoses and Aldohexoses

The production of chemicals from biomass is a very challenging process due to its diverse chemical composition. Lignin, cellulose and hemicellulose are the three main biopolymers of wood biomass, with cell walls ＆plant origin. Lignin has been chosen for the present studies due to its range of different linkages and structures. The present work involved a computational study of the most dominant lignin dimers and their vibrational structures, based on the Density Functional Theory method. Full geometry optimization of the compartments used the StoBe code with cluster model and non-local functional （RPBE） approach. The calculations of the vibrational frequencies were performed with harmonic approximations as well as an anharmonicity fit in the Morse potential function, as implemented in the StoBe code. In the case oflignin, the calculations included three different precursors based on： coumaryl alcohol, coniferyl alcohol and sinapyl alcohol. To represent the cellulose and hemicellulose derivatives, selected aldopentoses and aldohexoses （arabinose, xylose, glucose, galactose, and mannose） were considered. Presented here are the theoretical investigations for a variety of biomass derived compounds, to give the possibility of obtaining a theoretical VBD （Vibrations Basis Database） for experimental spectra interpretation. Such a database could be further used in the preliminary composition assessment of biomass derived substrates, which will be discussed here in more detail.

An Insight Into the Promise and Problems of Combining Life History and Grounded Theory Research

This paper describes the research carried out in partial fulfilment of the degree of doctor of education. The study was qualitative in nature with a phenomenological interpretive paradigm dominating the philosophical approach. The research methods adopted combined life story and grounded theory. As far as the author has been able to determine there are very few, if any studies which have applied this approach specifically to this area of research which investigated the influence life history has on attitude to lifelong learning. Twenty five respondents were interviewed in face-to-face informal interviews. The main aim was to elicit the respondent＇s subjective interpretation of the interaction between school, family, work, and learning within their lives. The researcher was then able to identify when they occurred and what or who made them particularly meaningful. This paper describes how initial decisions were made regarding the substantive area for the research. Sampling technique and method for collecting the data is discussed and a worked example is given of how the data was analysed. It is intended that this paper will give an insight into the challenge of combining these two much debated methods of research. The empirical data lead to some interesting findings which educators and policy makers will find helpful in order to strengthen the school, college, and workplace interface.