基于“立序”视角的小学数学教学思考

"序"是教师规范性教学的重要尺度。"序"的缺失使小学数学教学产生了许多问题。知识之序缺失导致学生认知模糊,认知之序缺失导致学生思维失稳,学习之序缺失导致学生理解肤浅。教师应建立对学习过程的科学,在教学实践中分清知识的主次,把握学习的次序,培养学生的数学思维。

An Improved Framework of Massive Superpoly Recovery in Cube Attacks Against NFSR-Based Stream Ciphers

A critical problem in the cube attack is how to recover superpolies efficiently.As the targeting number of rounds of an iterative stream cipher increases,the scale of its superpolies becomes larger and larger.Recently,to recover massive superpolies,the nested monomial prediction technique,the algorithm based on the divide-and-conquer strategy,and stretching cube attacks were proposed,which have been used to recover a superpoly with over ten million monomials for the NFSR-based stream ciphers such as Trivium and Grain-128AEAD.Nevertheless,when these methods are used to recover superpolies,many invalid calculations are performed,which makes recovering superpolies more difficult.This study finds an interesting observation that can be used to improve the above methods.Based on the observation,a new method is proposed to avoid a part of invalid calculations during the process of recovering superpolies.Then,the new method is applied to the nested monomial prediction technique and an improved superpoly recovery framework is presented.To verify the effectiveness of the proposed scheme,the improved framework is applied to 844-and 846-round Trivium and the exact ANFs of the superpolies is obtained with over one hundred million monomials,showing the improved superpoly recovery technique is powerful.Besides,extensive experiments on other scaled-down variants of NFSR-based stream ciphers show that the proposed scheme indeed could be more efficient on the superpoly recovery against NFSR-based stream ciphers.

Effect of Cultural Measures on Nutrient Contellts in Rice Plants with Erect Panicles

Field experiments were carried out with rice variety of Shennong 91 of short culms and erect panicles to study nutrient contents in high-yielding rice plants and to increase rice yield by appropriate fertilization.Nitrogen, phosphorus, potassium, magnesium, zinc, manganese, iron and copper contents in rice plants varied with different treatment factors. The relationship between the nutrient contents and treatment factors could be simulated using a multiple quadratic equation. The nutrient contents in plants should be appropriate for high-yielding rice. If the mean nutrient content in rice plants producing 11 t ha-1 or more of grain (μj) was set as the standard value and the standard deviation (σj) was set as the range of variation, the nutrient content in high-yielding rice plants should be μj±1.99σj. Rice leaves were sensitive to the nutrient elements. Heavy nitrogen dressing increased the content of nitrogen in rice plants. Sparse transplanting also increased nitrogen content. Improper application of nitrogen, phosphorus and potassium could affect the nutrient contents and decrease the grain yield.

Measurement of 3-D motion parameters of jacket launch based on stereo image sequences

To make sure that the process of jacket launch occurs in a seml-controlled manner, this paper deals with measurement of kinematic parameters of jacket launch using stereo vision and motion analysis. The system captured stereo image sequences by two separate CCD cameras, and then rebuilt 3D coordinates of the feature points to analyze the jacket launch motion. The possibility of combining stereo vision and motion analysis for measurement was examined. Resuhs by experiments using scale model of jacket confirm the theoretical data.

Symmetry Groups and Exact Solutions of New(4+1)-Dimensional Fokas Equation

In this paper, we investigate symmetries of the new （4＋1）-dimensional Fokas equation, including point symmetries and the potential symmetries. We firstly employ the algorithmic procedure of computing the point symmetries. And then we transform the Fokas equation into a potential system and gain the potential symmetries of Fokas equation. Finally, we use the obtained point symmetries wave solutions and other solutions of the Fokas equation. and some constructive methods to get some doubly periodic In particular, some solitary wave solutions are also given.

Darboux Transformation and New Soliton-like Solutions for （1＋1）-Dimensional Higher-Order Broer-Kaup System

In this letter, we construct a kind of new Darboux transformation for the （1＋1）-dimensional higher-order Broer-Kaup （HBK） system with the help of a gauge transformation of a spectral problem. By applying this new Darboux transformation, some new soliton-like solutions of the （1＋1）-dimensional HBK system are obtained.

Study on Due Procedure of Local Legislation of Marine Fishery Management

Based on the local legislation of marine fishery management, this paper takes the process of local legislation of marine fishery management in Liaoning Province as the main object of study, to explore the advantages and existing problems of the process of local marine fishery management. From the perspective of theory and practice, this paper analyzes the local legislative process deeply and discloses some problems, especially analyzes the main steps deeply in order to discover problems in the whole process from drafting to acting and proposes the corresponding solutions.

Environment map building and localization for robot navigation based on image sequences

SLAM is one of the most important components in robot navigation. A SLAM algorithm based on image sequences captured by a single digital camera is proposed in this paper. By this algorithm, SIFT feature points are selected and matched between image pairs sequentially. After three images have been captured, the environment’s 3D map and the camera’s positions are initialized based on matched feature points and intrinsic parameters of the camera. A robust method is applied to estimate the position and orientation of the camera in the forthcoming images. Finally, a robust adaptive bundle adjustment algorithm is adopted to optimize the environment’s 3D map and the camera’s positions simultaneously. Results of quantitative and qualitative experiments show that our algorithm can reconstruct the environment and localize the camera accurately and efficiently.

Diverse Voices and Democratic Policymaking： What Causes Japan＇s Nuclear Phase-Out Plan to Fail？

The nuclear disaster at Fukushima has raised questions about the nature of democratic policymaking in Japan. Focusing on nuclear policymaking post-Fukushima, this paper considers ways in which the diversity of public opinion can be connected with legislative processes. The disaster forced the government to rethink existing nuclear policies. To infuse public voices into government policy, the Democratic Party of Japan （DPJ） government introduced a new method of public participation called ＂national debates＂, comprising a series of public hearings, mass public comments, and deliberative polling. The government also attached importance to anti-nuclear rallies and opinion polls conducted by the media. The national debates highlighted that the majority of Japanese people supported a nuclear-free society; as a result, the government drafted a new energy plan to phase out nuclear power by 2039. Owing to both domestic and international opposition, the plan failed to become law. Progress was also impeded by the public＇s contradictory demands. However, this paper posits that inefficient legislative deliberation was the main factor behind the policy failure. The Japanese case suggests that effective legislative deliberation is crucial to assessing and coordinating numerous divergent public voices.

Isolation and identification of bacteria associated with the surfaces of several algal species

We conducted this study to assess the diversity of bacteria associated with the surfaces of algae based on 16S rDNA sequence analyses.Twelve strains of bacteria were obtained from the surfaces of the following four species of algae:Gracilaria textorii,Ulva pertusa,Laminaria japonica,and Polysiphonia urceolata.The isolated strains of bacteria can be divided into two groups:Halomonas and Vibrio,in physiology,biochemical characteristics and 16S rDNA sequence analyses.The phylogenetic tree constructed based on 16S rDNA sequences of the isolates shows four obvious clusters,Halomonas venusta,Vibrio tasmaniensis,Vibrio lentus,and Vibrio splendidus.Isolates from the surface of P.urceolata are more abundant and diverse,of which strains P9 and P28 have a 16S rDNA sequence very similar(97.5%-99.8%) to that of V.splendidus.On the contrary,the isolates from the surfaces of G.textorii,U.pertusa and L.japonica are quite simple and distribute on different branches of the phylogenetic tree.In overall,the results of this study indicate that the genetic relationships among the isolates are quite close and display a certain level of host species specificity,and alga-associated bacteria species are algal species specific.

Isolated Pancreatic Tuberculosis in Non-immunocompromised Patient Treated by Whipple's Procedure:a Case Report

PANCREATIC tuberculosis(TB)is a rare disease and its diagnosis is difficult because of the lack of specific clinical manifestations.Computed tomography(CT)and magnetic resonance imaging(MRI)have some diagnostic values in this disease,but it is easy to misdiagnose pancreatic TB as a pancreatic tumor.1 In this article,we present a case of non-immunocompromised patient developing an isolated pancreatic TB,report the CT and MRI findings,and the surgical procedure for it.

Rational design of stratified material with spatially separated catalytic sites as an efficient overall water-splitting photocatalyst

The development of metal sulfide catalysts with remarkable activity toward efficient overall photocatalytic water splitting remains challenging owing to the dominant charge recombination and deficient catalytic active sites.Moreover,in the process of water oxidation catalysis,the inhibition of severe photocorrosion is an immense task,requiring effective photogenic hole-transfer kinetics.Herein,stratified Co-MnO_(2)@CdS/CoS hollow cubes with spatially separated catalytic sites were rationally designed and fabricated as highly efficient controllable catalysts for photocatalytic overall water splitting.The unique self-templated method,including a continuous anion/cation-exchange reaction,integrates a Co-doped oxidation co-catalyst(Co-MnO_(2))and a reduction co-catalyst(CoS)on the nanocubes with uniform interface contact and ultrathin two-dimensional(2D)nanometer sheets.We demonstrate that the stratified Co-MnO_(2)@CdS/CoS hollow cubes can provide an abundance of active sites for surface redox reactions and contribute to the separation and migration of the photoionization charge carriers.In particular,CoS nanoparticles dispersed on the walls of CdS hollow cubes were identified as reduction co-catalysts accelerating hydrogen generation,while Co-MnO_(2) nanosheets attached to the inner walls of the CdS hollow cube were oxidation co-catalysts,promoting oxygen evolution dynamics.Benefiting from the desirable structural and compositional advantages,optimized stratification of Co-MnO_(2)@CdS/CoS nanocubes provided a catalytic system devoid of precious metals,which exhibited a remarkable overall photocatalytic water-splitting rate(735.4(H_(2))and 361.1(O_(2))μmol h^(−1) g^(−1)),being among the highest values reported thus far for CdS-based catalysts.Moreover,an apparent quantum efficiency(AQE)of 1.32%was achieved for hydrogen evolution at 420 nm.This study emphasizes the importance of rational design on the structure and composition of photocatalysts for overall water splitting.

The Policies of Seismic Risk Management： Case of the Protected Areas of Dellys and Tenes Cities, Algeria

The greater part of urban heritage, especially of the medium and small Algerian cities, is subject to a major seismic risk. The probability of a happening earthquake is strong, and the territories vulnerability is great. Legislative procedures are implemented to support urban heritage and managing natural disasters. In fact, the PPSMVSS （permanent plan of safeguard and enhancement of saved sectors） as an instrument of protection, preservation and enhancement of this heritage, in its content, does not guide decision makers on how to manage the vulnerability of preserved areas from the earthquake. After the disaster of the earthquake that hit the Algerian Centre （wilaya of Boumerdes） in 2003. A legislative framework was created while other texts have been adapted. Emergency measures operations are launched to preserve the under threat monuments and protected areas. Saved sectors of Dellys, in the wilaya of Boumerdes and T6n^s in the wilaya of Chlef, are all the time subjected to seismic risk. This article presents a comparative study of two PPSMVSS, Dellys and T6n6s, and the management of the vulnerability of their two safeguarded areas. As a result of this study, some indicators were identified to allow the development of plans for the protection and management natural risks of these protected areas.

Characterizations of Chinese isolates of Coxiella burnetii in the com1 gene sequence

Objective: To know some genetical characterizations of Coxiella burnetii Chinese isolates by comparing the coml gene sequence. Methods: com1 gene sequences of Chinese isolates were amplified, se-quenced, and analyzed by comparing our result and the previous published data. Results: Three different com1 sequences were identified in 7 Chinese isolates. Sequence comparison indicated that the isolates harboring the QpRS plasmid could be defined as a new group and, in addition, the isolates carrying the same plas-mid type showed similar com1 gene sequence. Conclusion: Study suggests that the classification of the group based on the coml gene sequence is highly associated with the plasmid type of the isolates and, however, little related to disease forms and geographical origins of the isolates.

Estimation of structural modal parameters by fourier transform with an optimal window

An adaptive Fourier Transform （FT） with an optimal window has been proposed for the time-frequency analysis of nonstationary time series. The method allows for a good estimation of both frequency and amplitude of the spectrum and can be easily applied to the general case of time-varying signals. The evaluation of the proposed approach has been performed on measured time-varying signals from a suspension bridge model and a steel frame model whose data have the typical non-stationary characteristics. The numerical results show that the proposed approach can overcome some of the difficulties encountered in the classic Fourier transform technique and can achieve higher computation accuracy.

Primer/Probe Optimization of RTq-PCR for Identification of Double-stranded （ds） RNA in Rhizoctonia solani

Rhizoctonia solani is a soil-borne pathogenic fungus with several distinct isolates that have been classified based on their anastomosis groups （AG＇s）. Many isolates of these fungi contain double-stranded viral RNA （dsRNA） that are cytoplasmic and viral in origin. Research in our laboratory has studied the epidemiology and molecular biology of viral RNA in R. solani, making it a useful biological model in the development of protocols for the rapid identification of biological agents. In the present study the dsRNA from the isolate EGR-4 which is characteristically large at 3.301 Kb was purified. Attempts to clone middle （M）-size dsRNA fragments from R, solani have been very difficult primarily due to artifacts that co-purify including large （L）-size dsRNA in the fungus. Various MgC12 concentrations were tested to optimize full length dsRNA PCR product. Magnesium is required for DNA polymerase, and EGR-4 requires a specific concentration; thus, several MgC1z concentrations were tested. The dsRNA was analyzed by gel electrophoresis. The gel-purified, nuclease-treated dsRNA was reverse transcribed into cDNA and ligated into the p-jet cloning vector and transformed using E. coli. All such clones were sequenced and forward and reverse primers were generated using BLAST sequence via Biosearch Technology. The plasmids were purified from transformed cultures and amplified using real-time PCR （RTqPCR） with the primers （reverse CCACCGGAAGAGGGAAATCC, forward AGCGCTGACCTTGCTATCGA ATC） and probe （5＇ Fam-AGTGCCGATCAGCCCTCCACCG-BHQ 1 3＇）. The ideal primer/probe concentration was determined through optimization by comparing the lowest threshold concentration （Ct） values using the plasmid cDNA as a template.

A Bilinear Bcklund Transformation and N-Soliton-Like Solution of Three Coupled Higher-Order Nonlinear Schrdinger Equations with Symbolic Computation

A bilinear Baecklund transformation is presented for the three coupled higher-order nonlinear Schroedinger equations with the inclusion of the group velocity dispersion, third-order dispersion and Kerr-law nonlinearity, which can describe the dynamics of alpha helical proteins in living systems as well as the propagation of ultrashort pulses in wavelength-division multiplexed system. Starting from the Baecklund transformation, the analytical soliton solution is obtained from a trivial solution. Simultaneously, the N-soliton-like solution in double Wronskian form is constructed, and the corresponding proof is also given via the Wronskian technique. The results obtained from this paper might be valuable in studying the transfer of energy in biophysics and the transmission of light pulses in optical communication systems.

Development of Instrument Control System Using Biosignals Created by the Change of Eyes Movement Sequence

A new biosi gn al control system that offers the disables the opportunities to control electric appliances is proposed.The four types of signals created by the eyes movements in four directions(up,down,left,and right),which are taken as four basic signals , are detected at the forehead.Permutation of 2 signals out of them creates 16 d ifferent signals.Permutation of 3 signals out of them creates 64 signals.They al l amounts to 84 control signals.They are thought to be applicable for the operat ion of some instruments.Furthermore,the dynamic biosignals created by the slow e yes movement is speculated to be applicable for the more convenient control of t hem.

Multi-objective Optimization Based on Unsteady Analysis Considering the Efficiency and Radial Force of a Single-Channel Pump for Wastewater Treatment

A multidisciplinary optimization was conducted to simultaneously improve the efficiency and reduce the radial force of a single-channel pump for wastewater treatment. A hybrid multi-objective evolutionary algorithm was coupled with a surrogate model to optimize the geometry of the single-channel pump volute. Steady and unsteady Reynolds-averaged Navier-Stokes equations with a shear stress transport turbulence model were discretized using finite volume approximations and were then solved on tetrahedral grids to analyze the flow in the single-channel pump. The three objective functions represented the total efficiency, the sweep area of the radial force during one revolution, and the distance of the mass center of sweep area from the origin while the two design variables were related to the cross-sectional area of the internal flow of the volute. Latin hypercube sampling was employed to generate twelve design points within the design space, and response surface approximation models were constructed as surrogate models for the objectives based on the values of the objective function at the given design points. A fast non-dominated sorting genetic algorithm for local search was coupled with the surrogate models to determine the global Pareto-optimal solutions. The trade-off between the objectives was determined and was described in terms of the Pareto-optimal solutions. The results of the multi-objective optimization showed that the optimum design simultaneously improved the efficiency and reduced the radial force relative to those of the reference design.

Stability Analysis of Solitary Wave Solutions for Coupled and(2+1)-Dimensional Cubic Klein-Gordon Equations and Their Applications

The searching exact solutions in the solitary wave form of non-linear partial differential equations （PDEs） play a significant role to understand the internal mechanism of complex physical phenomena. In this paper we employ the proposed modified extended mapping method for constructing the exact solitary wave and soliton solutions of coupled Klein-Gordon equations and the （2-1-1）-dimensional cubic Klein-Gordon （K-G） equation. The Klein-Gordon equations are relativistic version of Schr6dinger equations, which describe the relation of relativistic energy-momentum in the form of quantized version. We productively achieve exact solutions involving parameters such as dark and bright solitary waves, Kink solitary wave, anti-Kink solitary wave, periodic solitary waves, and hyperbolic functions in which several solutions are novel. We plot the three-dimensional surface of some obtained solutions in this study. It is recognized that the modified mapping technique presents a more prestigious mathematical tool for acquiring analytical solutions of PDEs arise in mathematical physics.