浅论航海雷达协助瞭望量程变换之必要性

船舶驾驶人员保持正规瞭望是确保航行安全的关键因素,采用雷达协助瞭望是进行正规瞭望的重要手段。为了能够充分地发挥雷达的助航功能,更加及时、准确地发现海上物标,从而规避航行风险,保障航行安全,文中结合笔者亲历或耳闻的航行事故和海事案例,从雷达瞭望远、近距离扫描的特点,雷达远、近距离档扫描使用的经验、教训等方面,简浅的论述了雷达协助瞭望时量程变换的必要性。

数字式自动变换量程槽电压表的研制

1引言铝电解生产是大直流、低电压，具有很强的磁场，一个系列由少则几十台、多则上百台电解槽串联组成；电解槽的槽电压是电解工人监视槽子运行状态、正确摆布技术条件的重要依据，正常情况下，槽电压为4V左右，发生阳极效应时，高达几十伏甚至上百伏。早期使用的是指针?..

双量程紫外光离子化气体浓度检测电路设计

大量程气体传感器检出限过高，不能适应低浓度有毒有害气体环境的检测。为此以C8051f040单片机为核心器件，采用内部A／D、多路模拟开关CD4053B，设计了一种双量程紫外光离子化气体测量系统，以实时检测待测气体浓度并用数码管显示。在计算机自动配气系统中测试了乙烯浓度，在0～200×10^-6范围内，小量程的测试误差≤O．02×10^-6，明显优于大量程的测试误差≤O．3×10^-6。测试结果表明，该系统解决了大量程传感器在检测低浓度气体时遇到的精度低的难题。

多量程紫外光离子化气体传感器的设计

紫外光离子化气体传感器主要用于复杂环境污染综合快速评价,它测量精度高,响应快速,越来越受到人们的重视。在研究过程中发现,高量程传感器检测有毒有害气体的检出限过高,不能适应低浓度有毒有害气体环境的检测。本文基于模拟开关芯片CD4052B设计了量程自动转换机制,既满足了高量程性能要求,又具备低检出限性能,以简单、易操作的方法解决了高量程与低检出限的兼容问题。

不同量程信号融合抑制噪声新方法

针对高精度测量电路中采样通道和模数转换器(A/D)产生的噪声对精度的影响问题,提出了对同一信号采用多通道同时进行采样,并结合多通道数据相关叠加算法对数据进行融合来减小测量噪声的新方法.在实际测量过程中,利用A/D在不同的量程下信噪比不同的特点,采用一个固定量程的通道和一个可变量程(随着信号量值变化而变化)通道同时对信号进行采样;这样,在降低噪声的同时还可以提高信号的分辨率.实验证明,该方法能有效抑制噪声,保持测量的最高分辨率.此外该方法具有很好的实时性,适用于高速信号处理的场合.

单片机在智能微光功率计中的应用

本文阐述了智能微光功率计的原理及设计方法，在此基础上研制出的智能微光功率计具有自动量程变换、光谱响应自动校准、数据采集和处理的自动化、程控LED显示等功能，从而实现了弱信号的精确测量和测试过程的自动化。

高压型智能绝缘参数测试仪的研制

对高压型智能绝缘参数测试仪的测试方法及关键电路进行综合分析比较,对容量大、纹波小的可调式高压电源及灵敏准确的微电压测量电路作了较深入的分析。同时论述了设计中必须注意的问题,指出了抗干扰及保护措施的意义并介绍了一种实用的处理方法。该方法在应用中取得了良好的效果。

N-Soliton Solutions of General Nonlinear Schrdinger Equation with Derivative

The bilinear equation of the genera/nonlinear Schrodinger equation with derivative （GDNLSE） and the N-soliton solutions are obtained through the dependent variable transformation and the Hirota method, respectively. The bilinear equation of the nonlinear Schrodinger equation with derivative （DNLSE） and its multisoliton solutions are given by reduction.

Exact Wave Function of a Time-Dependent Quantum System

To solve the problem in dispute about a Schrdinger equation with time-depenelent mass and frequency, by means of a simple transformation of variables, the time-dependent Schrdinger equation is transformed into the time-independent one first and then an exact wave function can be found.

Conservation Laws and Symmetries of the Levi Equation

The conservation laws of the Levi equation are presented.Two types of symmetry of the Levi equationhierarchy are deduced.Further it is proved that these symmetries construct an infinite-dimensional Lie algebra.

Breather Lattice Solutions to Negative mKdV Equation

In this paper,dependent and independent variable transformations are introduced to solve the negativemKdV equation systematically by using the knowledge of elliptic equation and Jacobian elliptic functions.It is shownthat different kinds of solutions can be obtained to the negative mKdV equation,including breather lattice solution andperiodic wave solution.

Solution Transformations and Their Effects on the Systems with Open Boundary Conditions

The solution transformations and properties of the -matrices for two-component systems under these transformations are analyzed in details. Not all transformed -matrices can be put into the Skalyanin's formalism. For those -matrices with all required properties, the effects of solution transformations to the six- and eight-vertex systems with open boundary conditions are discussed. These effects can be one of the following types: The Hamiltonian is invariant or transposition-invariant or made in a similarity transformation, or its coupling coefficients are multiplied by an overall factor, or the spin of the system is rotated around the axis or/and reflected with respect to some plane. In these cases, the transformed systems remain to be integrable.

Noether Symmetry Can Lead to Non-Noether Conserved Quantity of Holonomic Nonconservative Systems in General Lie Transformations

For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,the Noether symmetry, Lie symmetry, and Noether conserved quantity are given. Secondly, the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations is obtained. Finally, a set of nonNoether conserved quantities of the system are given by the Noether symmetry, and an example is given to illustrate the application of the results.

Wronskian Form of N-Solitonic Solution for a Variable-Coefficient Korteweg-de Vries Equation with Nonuniformities

By the symbolic computation and Hirota method, the bilinear form and an auto-Backlund transformation for a variable-coemcient Korteweg-de Vries equation with nonuniformities are given. Then, the N-solitonic solution in terms of Wronskian form is obtained and verified. In addition, it is shown that the （N - 1）- and N-solitonic solutions satisfy the auto-Backlund transformation through the Wronskian technique.

Quantum Fourier Transform and Phase Estimation in Qudit System

The quantum Fourier transform and quantum phase estimation are the key components for many quantum algorithms, such as order-finding, factoring, and etc. In this article, the general procedure of quantum Fourier transform and phase estimation are investigated for high dimensional case run in a qudit quantum computer, and the quantum circuits are They can be seen as subroutines in a main program given.

Pseudopotentials,Lax Pairs and Bcklund Transformations for Generalized Fifth-Order KdV Equation

Based on the method developed by Nucci, the pseudopotentials, Lax pairs and the mngulanty mamtoia equations of the generalized fifth-order KdV equation are derived. By choosing different coefficient, the corresponding results and the Backlund transformations can be obtained on three conditioners which include Caudrey-Dodd-Cibbon- Sawada-Kotera equation, the Lax equation and the Kaup-kupershmidt equation.

Alternate Form of Damped Wave Conduction and Relaxation Equation a Capite Adcalcem in Temperature

An alternate non-Fourier heat conduction equation is derived from consideration of translation motion of spinless electron under a driving force due to an applied temperature gradient. This equation is a eapite ad calcem,temperature. Elimination of the rate of change of velocity with respect to time leads to a non-Fourier heat conduction equation with a accumulation of temperature or ballistic term in it. The new constitutive heat conduction equation is combined with the energy balance equation in one dimension. The governing equation for transient temperature a partial differential equation （Eq. （23）） is solved for by the method of Laplace transforms. The problem considered is the semi-infinite medium with constant thermo physical properties with constant wall temperature boundary condition. A closed form analyticalexpression for the transient temperature was obtained （Eq. （36）） after truncation of higher order terms in the infinite binomial series and use of convolution and lag properties. This solution is compared with that obtained using the parabolic Fourier model and the damped wave model as presented in an earlier study. The predictions of Eq. （36） are closer to the Fourier model. The convex nature of the temperature curve is present.

Hierarchically nanostructured porous TiO_2(B) with superior photocatalytic CO_2 reduction activity

Hierarchically nanostructured, porous TiO_2(B) microspheres were synthesized by a microwave-assisted solvothermal method combined with subsequent heat treatment in air. The materials were carefully characterized by scanning and transmission electron microscopy, X-ray diffraction, CO_2 adsorption, and a range of spectroscopies, including Raman, infrared, X-ray photoelectron and UV-Vis spectroscopy. The hierarchical TiO_2(B) particles are constructed by ultrathin nanosheets and possess large specific surface area, which provided many active sites for CO_2 adsorption as well as CO_2 conversion. The TiO_2(B)nanostructures exhibited marked photocatalytic activity for CO_2 reduction to methane and methanol. Anatase TiO_2 and P25 were used as the reference photocatalysts. Transient photocurrent measurement also proved the higher photoactivity of TiO_2(B) than that of anatase TiO_2. In-situ infrared spectrum was measured to identify the intermediates and deduce the conversion process of CO_2 under illumination over TiO_2(B) photocatalyst.

Two Hierarchies of New Differential-Difference Equations Related to the Darboux Transformations of the Kaup–Newell Hierarchy

Two hierarchies of new nonlinear differential-difference equations with one continuous variable and one discrete variable are constructed from the Darboux transformations of the Kaup-Newe11 hierarchy of equations. Their integrable properties such as recursion operator, zero-curvature representations, and bi-Hamiltonian structures are stud- ied. In addition, the hierarchy of equations obtained by Wu and Geng is identified with the hierarchy of two-component modified Volterra lattice equations.

On Light-Like Extremal Surfaces in Curved Spacetimes

In this paper, we find that under a diffeomorphic of nonlinear geodesic equations are concerned with light-like extremal surfaces in curved spaeetimes. It is interesting to transformation of variables, the light-like extremal surfaces can be described by a system Particularly, we investigate the light-like extremal surfaces in Schwarzschild spacetime in detail and some new special solutions are derived systematically with aim to compare with the known results and to illustrate the method.