数量关系:小学生数学思维发展的蹊径

数学是研究数量关系和空间形式的科学,"数量关系"是指在同一类数学问题中总结出的规律性的揭示数量间的本质关系。数量关系具有高度的抽象性和广泛的适用性,它是从纷繁复杂的现实世界中发现总结提炼出来的,同时又能普遍应用于现实问题的解决,在解决实际问题中具有重要意义。学生对数量关系运用水平的强弱在某种程度上显示着其数学水平的高低,数量关系是帮助他们快速有效地解决数学问题的指南针,为他们指明方向。

让学生经历数学知识形成的过程

小学数学教学重视让学生经历数学知识形成的过程。教学中要多给学生提供经历过程的空间,引导学生用数学的眼光去发现,用数学的思维去探索,用数学的模式去构建,以实现学生是数学的主体。

ASSESSMENT OF MILITARY AIRFIELD OBSTACLE FREE SPACE BASED ON GIS

A mathematical model of obstacle limit surfaces for military airfield obstacle free space is established through airfield obstacle free space analysis.Based on the model,triangle mesh elevation model of military airfield obstacle free space is built by using the software-ArcGIS,and the 3-D display result is obtained.It is convenient to evaluate military airfield obstacle for superimposing digital elevation model（DEM）with military airfield topographic map.Thus it improves the efficiency greatly.It lays the foundation for the application of geographic information systems（GIS）in the management of military airfield obstacle free space.

A Paraffin Sectioning Method Without Using the Microtome and an Analysis Method for Optical Information of the Plant Anatomical Digital Photographs

[Objective] The research aimed to study a paraffin method without using the microtome,and also introduced an analysis method for optical information of the plant anatomical digital photographs.[Method] The plant material softened or not was embedded in paraffin according to the paraffin method.Cut the thin paraffin sections from the paraffin block with a sharp two-sided blade under anatomical lens.The thin material sections rolled up when they were cut off.Took the section rolls to a slide,and then heated them to melt the paraffin section roll.When the paraffin melted,the sections of plant material were rolled out.After the common or simplified procedures of staining and mounting,the preparations were finished.When an anatomical digital photograph was processed,copy it into the word file and two copies of the original photograph were obtained.One copy was selected to make it to be a negative photograph,and then press the key ＂Press Screen＂ to copy the screen frame.After it was copied into the word file,cut of the unnecessary parts and other operations were carried out,then processed photograph was obtained.[Results] The anatomical preparation for research was gotten.The analyzed digital photograph of the leaf structure of Salix matsudana var.matsudana f.tortuosa has some a three-dimensional effect,and the different leaf structures and cells,e.g.cuticle,cell wall,protoplast,vein,etc.can be identified easily.[Conclusion]The paraffin method without using the microtome has advantages of low cost and higher efficiency,which could be applied by the beginner or in the time without a microtome to be used.The analysis of the plant anatomical digital photographs can acquire more structural information than the original digital photographs,which shows the potentiality and prospects of the optical information analysis of the microscopic imagery and its digital photograph.

Evaluation System and Actualization of Selection Supplier in ERP Enterprise

Suppliers become an essential factor of enterprise competitiveness. The analytic hierarchy process is a kind of Decision-making method with the combination of quantity and quality. This paper presents the evaluation system of supplier selection, using Analytic Hierarchy Process (AHP) method to select the optimum supplier in Enterprise Resource Planning (ERP) enterprise. In order to reduce factor of manmade and increase exactitude, this paper innovates to use a real database in ERP system for evaluation. It also gives an example that one enterprise selects supplier.

MATHEMATICAL MODEL FOR ACCESS MODE OF CONTENTION-COLLISION CANCELLATION IN A STAR LAN

I type system model of CCCAM(Contention-Collision Cancellation Access Mode) is studied through mathematical modelling and simulation. There are two innovations: (1) in the process of mathematical modelling, the instance of 'serving customers unsuccessfully' is taken into account; (2) the time at which customers depart after having been served successfully are chosen to be the embedded point, thereby 'free period' is introduced reasonably. So the mathematical modelling and analysis result in this paper are significant for application of wire star LAN and wireless star LAN.

Establishment of an index system for evaluating outstanding biomedical scientists for science foundation of Shanghai

Objective:To establish a scientific,objective and applicable index system for evaluating out- standing biomedical scientists for science foundation of Shanghai.Methods:According to the principal in- dices that have been used in the developed countries for evaluating their talented personnel and the reality of our country,an index system was set up to evaluate the outstanding biomedical scientists for Shanghai science foundation.The following parameters were used to simplify the indices.,correlation coefficient, multiple correlation coefficient,partial correlation coefficient,creditability,and discriminatory power. And analytic hierarchy process was used to determine the weights of each index.Results and Conclusions: The established index system is scientific and applicable;it is helpful for cultivating and evaluating out- standing biomedical scientists.

Study and application analysis of random noise adaptive morphological fi lter algorithm reconstruction for seismic signals

In this study,a new adaptive morphological filter is developed based on the mathematical morphology algorithm and characteristics of the subtle differences in the waveform morphology in seismic data.The algorithm improves the traditional morphological dilation and corrosion operations.In this study,we propose a multiscale adaptive operator based on the principle of morphological structural“probes”and present the corresponding mathematical proof.Simulation experiments and actual seismic data processing results show that compared with traditional morphological filters,the constructed OCCO-based multistructure adaptive morphological filter can suppress noise to the greatest extent.Moreover,it can effectively improve the SNR of the images,and offers great application prospects.

Numerical Characteristics of Fuzzy Numbers Based on Credibility Measure

The numerical characteristics of fuzzy numbers include the optimistic value, pessimistic value, expected value, and the variance. We mainly provide the calculation formulae of several numerical characteristics of fuzzy numbers based on credibility measure. Especially, the variance of symmetric fuzzy numbers is formulated, and a super bound for the variance of fuzzy numbers is presented. Meanwhile, some conclusions relative to credibility measure, optimistic and pessimistic values are also given.

Linguistic Truth Values Lattice Implication Algebras

In order to study uncertainty reasoning and automatic reasoning with linguistic terms, in this paper, the set of basic linguistic truth values and the set of modifiers are defined, according to common sense; partially orderings are defined on them. Based on it, a lattice implication algebra model L18 of linguistic terms is built; furthermore, its some basic properties are discussed.

Collection Cost Screening Mechanism in a Closedloop Supply Chain

Recently, the product remanufacturing has been a hot topic in the field of operational management, and more manufacturers are beginning to recover the value in their end of life （EOI.） products hy remanufacturing. This paper focuses on the closed loop supply chain where the retailer takes charge of not only retail, but also col- lection. There are two possible types of the retailer＇s collection cost as an assumption, i.e. high cost or low cost, and the retailer knows his type, whereas the manufacturer only has a prior prohability over the two possible cost types. This paper deploys the contracts with which the manufacturer can screen the type of the retailer to improve her profit under incomplete information. As a result, the pooling contract can perfectly coordinate the decentral- ized system under incomplete information, but the manufacturer obtains the lower profit; nevertheless, with the separating contracts the manufacturer obtains the larger profits though the system profit is lower.

New Multisignature Scheme Based on Bilinear Pairings

Two digital multisignature schemes based on bilinear pairings were proposed. One of them is the sequential digital multisignature, and the other is the broadcasting digital multisignature. The scheme has the same security as JI and LIs multisignature scheme, but the new scheme has the lower computation. So the new scheme is the multisignature which has high security and low computation. It has the theory meaning and extensive application under the condition of SmartCard, etc.

A frame synchronization solution for orthogonal frequency division multiplexing system

To improve frame synchronization precision, a scheme named training symbol correlation （TSC） is presented for orthogonal frequency division multiplexing （ OFDM ） system. Based on the solution from Schmidl and Cox, a timing metric related to TSC scheme is put forward and examined. The specific method to select a threshold value provides more precise detection results, which can be shown by performance comparison between the two schemes through Monte Carlo simulation. Taking IEEE 802.1 la WLAN standard as an example, the proposed approach is superior to the most popular Schmidl scheme in terms of BER.

Context-Aware Tour Planning System Based on Satisfaction Model

With the development of communication and ubiquitous computing technologies, context-aware services, which acquire contextual information of users and environment, have become critical applications providing customization in mobile commerce. Meanwhile, tourism has attracted increasing attention as a high value-added service and a hot academic topic. However, the research on how to provide tour services based on context-aware services is in fact still at an early stage, limited to concept elaboration, service framework discussion, prototype system development etc. In this paper, we summarized the previous researches on context-aware services to establish the research foundation, put forward a way of analyzing a tour planning problem with a modified model of Traveling Salesman Problem （TSP） and Vehicle Routing Problem （VRP）, and we applied an innovated Resource Constrain Project Scheduling Problem （RCPSP） mathematical model to solve the tour planning problem based on context information. The simulation under branch and bound algoritban evaluated the validity of our solution.

Knowledge Discovery for Event Series Decision Based on Rough Set

To make decisions about event series is part of our life, and to discover knowledge from these decisions is of great significance in the field of controlling and decision-making. The paper takes event series as the exterior form of movements with the dynamic attributes, and gets the Markov transition probabilities matrix to express those attributes with statistics. First, according to the matrix, the decision table is constructed. Then, by reducing attributes based on rough set theory, the decision table is reduced, and the decision rules are acquired as well. Finally we make the decision through defining rule distance and taking the minimum rule distance as decision principle. Followed is an example, which proves that the algorithm is feasible and effective to the event series decision.

Improvement of Euler＇s Method Using Particle Swarm Optimization

Many problems in applied mathematics lead to ordinary differential equation. In this paper, a considerable refinement and improvement of the Euler＇s method obtained using PSO （particle swarm optimization） was presented. PSO is a technique based on the cooperation between particles. The exchange of information between these particles allows to resolve difficult problems. This approach is carefully handled and tested with an illustrated example.

New Eigenmodes of Propagation in Quadratic Graded Index Media and Complex Fractional Fourier Transform

By introducing a convenient complex form of the α-th 2-dimensional fractional Fourier transform (CFFT) operation we find that it possesses new eigenmodes which are two-mode Hermite polynomials. We prove the eigenvalues of propagation in quadratic graded-index medium over a definite distance are the same as the eigenvalues of the α-th CFFT, which means that our definition of the α-th CFFT is physically meaningful.

Properties of Paths in ROBDD and Its Application to Signal Probability Calculations

The properties of the paths in an ROBDD representation of a Boolean function are presented and proved in the present paper, and the applications of ROBDD in calculating signal probability are also discussed. By this method, the troublesome calculation of the correlation among the nodes, which is caused by the re-convergent fan-out in digital system, can be avoided and power estimation can be faster than simulation-based method in [1].

Extracting Acoustic Source Information of Shipping Noise for Dynamic Ambient Noise Modelling

Shipping traffic is one of the largest contributors to anthropogenic noise in the ocean. Noise generated by merchant ships elevates natural occurring ambient noise level by 20-30 dB in many areas of the world＇s ocean. In order to model the contributions of the noise generated by merchant ships to underwater ambient noise level correctly, a database that consists of the source levels as a function of frequency for different types of ships is essential. This paper describes the conceptual design, with an emphasis on the characteristics of shipping noise as sound sources, of a marine noise database. It was developed for providing necessary parameters for underwater ambient noise modelling. The parameters relevant to shipping noise modelling are organized in two catalogues： （l） source-receiver geometry related parameters, namely the coordinates of the ships at a given time period, as well as the sizes/types of the ships from which the noise source depths may be derived, and （2） acoustically relevant parameters, i.e., the acoustic SLs （source levels） at given frequencies. An example is presented here to demonstrate the efficacy of this database. The study area is a 117 × 55 km2 region off the coast of La Spezia, Italy, in the Mediterranean Sea.

Dual Waterfilling Power Allocation Algorithm in MIMO Systems

Aiming at the problem of resource allocation in multiuser multi-input multi-output (MIMO)systems,a new power allocation algorithm based on dual waterfilling is proposed.Block diagonalization is adopted to cancel the inter-user interference,and then the complete diagonalization method is employed to derive the spatial sub-channels for each user.The overall power of the system is divided among users based on each user’s large scale fading;then the power of each user is further allocated to its spatial sub-channels based on the small scale fading.Simulation results show that compared with the existing resource allocation strategies,the proposed algorithm can provide more ergodic capacity for multi-user MIMO systems.When the total transmit power is 100w,it has 15%capacity advantage over the traditional waterfilling method.