“学”数学更是“用”数学

从生活中找教育,选择生活化内容、为生活而服务,强化数学的功能性、游戏中学习,妙用自然教学法三个方面,探讨了把数学生活化的教学方法,这是值得我们在实践中推广应用的。

“教学做合一”在高中数学教学中的实践

“做”数学的含义,怎样“做”数学:(一)教师变学生——“做”数学的前提;(二)教学生活化——“做”数学的关键;(三)思维创新性——“做”数学的目标。

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!

Study of Controlling Clutch Engagement for AMT Based on Fuzzy Logic

The control of the clutch engagement for an automatic mechanical transmission in the process of a tracklayer getting to start is studied. The dynamic model of power transmission and automatic clutch system is developed. Using tools of Simulink, the transient characteristics during the vehicle starting, including the jerk and the clutch slip time, are provided here. Based on the analyses of the simulation results and driver’s experiences, a fuzzy controller is designed to control the clutch engagement. Simulation results verify its value.

Numerical simulation of rock electrical properties based on digital cores

In this paper, we obtained three dimensional digital cores using X-ray CT to describe the rock microstructure and applied the open morphology algorithm to simulate oil and formation water distribution in the pore space at different water saturations during the oil-displacing water flood process. The resistivity, formation factor, and resistivity index of rocks were calculated using the finite element method （FEM） and we studied the effect of rock wettability on electrical properties. The numerical simulation results indicate that the simulated formation factor and resistivity index of the water wet rock agrees well with experiments over the whole range of water saturation and extends the traditional resistivity experiment. The rock wettablilty has a large influence on the rock resistivity index. The resistivity and saturation exponent of oil wet rock are obviously larger than three of water wet rock.

Integrity of Four Theories on Natural Selection Unit

[Objective] The aim was to study the internal relationship of the four theories on natural selection unit. [Method] The value field of fitness of heterozygote was investigated by constructing mathematical models, to clarify the internal relations of the four theories on natural selection unit. [Result] According to mathematical modes constructed in the study, only the mutated genes meet the requirements of natural selection on heterozygous and homozygous aspects, as well as show high fitness in heterozygous condition, could the mutated genes be kept, giving consideration to both individual and population adaptation. Thus, this methodology theoretically inte- grates the theories of individual selection, collective selection, and genetic selection as well as Kimura＇s neutral theory of health information. [Conclusion] The result of this study suggested that the four theories on natural selection unit can co-exist, and share common premises.

Skeleton extraction of boiler flame images based on mathematical morphology

In this paper, a method and algorithm of skeleton extraction based on binary mathematical morphology is presented. Sequential structuring elements (SEs) is also studied, which is the key problem of skeleton extraction. The examples of boiler flame image processing show that the detected skeletons can present the geometric shape of flame images well.

Primary Research on WSeveral Theorems,Laws and Corollaries of Hydrology

The conceptions of theorems, laws and corollaries of hydrology were put forward. Combining with hydrology practice, several theo- rems, laws as well as corollaries of hydrology were summarized. The study provided some references for accelerating the development of hydrology theory in these aspects and promoting the improvement of its production technology.

RESEARCH ON SATELLITE IMAGE PROCESSING AND RECOGNITION WITH PARALLEL ALGORITHM

Using the method of mathematical morphology,this paper fulfills filtration,segmentation and extraction of morphological features of the satellite cloud image.It also gives out the relative algorithms,which is realized by parallel C programming based on Transputer networks.It has been successfully used to process the typhoon and the low tornado cloud image.And it will be used in weather forecast.

Mechanical response of roof rock mass unloading during continuous mining process in underground mine

Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method of the affected zone theory, and the deterioration laws of mechanics parameters of unloading rock mass, the continuous mining process in underground mine was analyzed by the software MIDAS/GTS, the mechanical response of roof rock mass unloading was studied, and the differences were analyzed with the conventional simulation. The result shows that the maximum tensile stress, subsidence displacement and equivalent plastic strain of roof rock mass are 1.5 MPa, 20 cm and 1.5% in the unloading analysis, while 1.0 MPa, 13 cm and 0.9% in the conventional analysis. The values of unloading analysis, which are also closer to the actual situation, are greater than those of conventional analysis; the maximum step in continuous mining is 48 m, which shows that the induced treatment of the roof should be carried out after 2 mining steps

A Novel Algorithm to Extract Weighted Critical Area

inductive fault analysis is a technique for enumerating likely bridges that is limited by the weighted critical area computation. Based on the rectangle model of a real defect and mathematical morphology, an efficient algorithm is presented to compute the weighted critical area of a layout. The algorithm avoids the need to determine which rectangles belong to a net and the merging of the critical area corresponding to a net pair. Experimental resuits showing the algorithm＇s performance are presented.

Void defect detection in BGA solder joints using mathematical morphology

Voids are one of the major defects in ball grid array （BGA） solder joints due to a large amount of outgassing flux that gets entrapped during reflow. X-ray nondestructive machines are used to make voids visible as lighter areas inside the solder joints in X-ray images for detection However, it has always been difficult to analyze this problem automatically because of some challenges such as noise, inconsistent lighting and void-like artifacts. This study realized accurate extraction and automatic a-nalysis of void defects in solder joints by adopting a technical proposal, in which Otsu algorithm was used to segment solder balls and void defects were extracted through opening and closing operations and top-hat transformation in mathematical mor-phology. Experimental results show that the technical proposal mentioned here has good robustness and can be applied in the detection of voids in BGA solder joints.

FTIR Spectroscopic Study of Broad Bean Diseased Leaves

[Objective] The aim was to indentify diseased leaves of broad bean by vibra- tional spectroscopy. [Method] In this paper, broad bean rust, fusarium rhizome rot, broad bean zonate spot, yellow leaf curl virus and normal leaves were studied using Fourier transform infrared spectroscopy combined with chemometrics. [Result] The spectra of the samples were similar, only with minor differences in absorption inten- sity of several peaks. Second derivative analyses show that the significant difference of all samples was in the range of 1 200-700 cm2. The data in the range of 1 200- 700 cm＇ were selected to evaluate correlation coefficients, hierarchical cluster analy- sis （HCA） and principal component analysis （PCA）. Results showed that the correla- tion coefficients are larger than 0.928 not only between the healthy leaves, but also between the same diseased leaves. The values between healthy and diseased leaves, and among diseased leaves, are all declined. HCA and PCA yielded about 73.3% and 82.2% accuracy, respectively. [Conclusion] This study demonstrated that FTIR techniques might be used to detect crop diseases.

Mathematical Definitions of Operators for Cartographic Generalization

This paper puts forword 11 cartographic generalization operator models and introduces their mathematical definitions,and thus a precise mathematical form and quantitative description has been given to these formerly limited qualitative concepts.The meaning of mathematical definition of operators for cartographic generalization and the application prospect in computer_aided cartography (CAC) is stated.ract The Jurassic strata in Jingyan of Sichuan containing the Mamenchinsaurus fauna are dealt with and divided in this paper. The Mamenchisaurus fossils contained there are compared in morphological features and stratigraphically with other types of the genus on by one. The comprehensive analysis show that the Mamenchisaurus fauna of Jingyan appeared in the early Late Jurassic and is primitive in morphology. The results of the morphological identification and stratigraphical study agree with each other. Their evolutionary processes in different apoches of the Late Jurassic also made clear. Key words Jingyan, Sichuan, Mamenchisaurus Fauna, stratigraphy, evolution

Primary study on Nosema bombycis Infecting the Insect of Drosophila

[ Objective ] The aim of this study was to investigate the infectivity of Nosema bombycis to drosophila, which offered a new vision for systematical studies on the infection mechanism of Nosema bombycis, and also provided reference for the bio-control effect of Nosema bombycis. [ Method ] Nosema bombycis was used to feed wild type and mutant drosophila, and the morphological observation of Nosema bombycis in drosophila body fluid was also analyzed by calcofluor white M2R fluorescent staining. [ Result] Nosema bombycis could infect drosophila, and the number of Nosema bombycis in the infected mutant drosophila was higher than that in wild type drosophila. [ Conclusion ] Nosema bombycis can infect drosophila, which provides primary reference for studies on the infectivity of Nosema bombycis to other hosts and also lays a foundation for further study on the infection mechanism of Nosema bombycis.

Correlation Analysis of Two Hydrochemical Factors Affecting the Distribution of Ceratopteris thalictroides in China

[ Objective] This study was to analyze the two hydrochemical factors affecting the distribution of Ceratopteris thalictroides, further to provide basis for its habitat protection and population restoration. [ Method ] Twenty two hydrochemical parameters of 22 sampling sites in China＇s tropical and subtropical zones were respectively averaged for calculating their variation coefficients, of which the two showing significant differences were used for multiple comparisons and correlation analyses via least significant difference and correlation coefficient. E Result ] The correlation coefficients of all the 22 tested hydrochemical parameters varied hugely, but only pH value and conductivity showed significantly differences in two water body （type A and type B）. Analysis of correlation presented that pH value were positively correlated with conductivity; further the multiple comparisons showed that the significant difference of pH value was higher than that of conductivity. [Conclusion] With regard to the two hydrochemical parameters showing significant differences, pH value influences the distribution of C. thalictroides more.

Limit Cycles in the Stability Analysis of a Chemical System

Aris and Amundson studied a chemical reactor and obtained the two equationsDaoud showed that at most one limit cycle may exist in the region of interest. Itis showed in this paper that other singular points exist and that a stable limitt cycle existsaround the singularity (1/2, 2) when K∈(9-δ, 9).

Image edge detection based on nonsubsampled contourlet transform and mathematical morphology

A novel algorithm for image edge detection is presented. This algorithm combines the nonsubsampled contourlet transform and the mathematical morphology. First, the source image is decomposed by the nonsubsampled contourlet transform into multi-scale and multi-directional subbands. Then the edges in the high-frequency and low-frequency sub-bands are respectively extracted by the dualthreshold modulus maxima method and the mathematical morphology operator. Finally, the edges from the high- frequency and low-frequency sub-bands are integrated to the edges of the source image, which are refined, and isolated points are excluded to achieve the edges of the source image. The simulation results show that the proposed algorithm can effectively suppress noise, eliminate pseudo-edges and overcome the adverse effects caused by uneven illumination to a certain extent. Compared with the traditional methods such as LoG, Sobel, and Carmy operators and the modulus maxima algorithm, the proposed method can maintain sufficient positioning accuracy and edge details, and it can also make an improvement in the completeness, smoothness and clearness of the outline.

Biomechanical research of knee joint during the process of running

To study the effect of speed on the biomechanics of a knee joint during running, a biomechanical model of human lower limb joints is established based on the Kane method and semi-physical simulation. Experiments on the running process were made at different speeds for healthy young men. The influence of running speed on knee Joint motion is analyzed quantitatively and a mathematical model of the knee angle is established with speed as the independent variable. Results show that, at the moment of the heel contacting with theground, with the increase of speed, the more, and the calf and thigh are closer to the same line. In the middle stage of a gait cycle, the thigh stretches back, and then the calf and thigh are close to collineation. At that moment, the stretch of the posterior cruciate ligament is the largest, and the slower the speed, the more obvious the collineation. The maximal joint angle of the calf relative to the thigh appears in the later stage, and themaximal joint angle increases with the increase of the velocity. With the increase of the running speed, the phase of the cure of knee angle moves forward. The results can be used in the field of rehabilitation robotics and humanoid robot.

Analysis of the Current Situation of Spoken Foreign Language Teaching and Learning in Ethnic Regions

With the enhancement of friendship between different nations, foreign language learning has become more and more important. In particular, spoken language is playing a vital role in foreign language learning and practice. In order to improve foreign language teaching and learning proficiency in ethnic regions, the author analyses the current situation of spoken foreign language teaching and learning in ethnic regions and suggests some ways to solve the existing problems.