基于Dot Net平台在线考试系统的设计与实现

随着E-Learning的发展,各网络教育学院和企业都相继开发出了基于WWW的远程教学系统,传统的笔试正向基于网络平台的网上考试逐步转化。文章提出了Dot Net平台下在线考试系统的设计思路,详细分析了系统的各主要模块的功能,给出了具体的实现过程和方法。

Dot NET框架下Com与ComGIS的发展对GIS软件组织方式的影响

为了与Java竞争,微软公司推出了Dot NET和Dot NET组件技术,Dot NET组件技术比COM更加完善,微软公司也计划逐步用.NET组件技术淘汰COM。在这一新的技术条件下,源于Microsoft的COM及以其为基础的ComGIS技术都在发生着巨大的变化。本文立足于项目开发中的实际经验,以商用大型GIS软件的最新发展成果为参考,对在Dot NET框架下COM与ComGIS的发展进行了全面的分析,并以此为基础,分析了GIS软件组织方式受到的影响。

Dot NET框架下Com与ComGIS的发展对GIS软件组织方式的影响

立足于项目开发中的实际经验,以商用大型GIS软件的最新发展成果为参考,对在Dot NET框架下COM与ComGIS的发展进行了全面的分析,并以此为基础,分析了GIS软件组织方式受到的影响。

基于微软Dot Net框架的质监行政事项网上申报审批系统

建立行政事项网上申报审批系统是加快推进信息化建设,实现电子政务的重要内容。本文介绍了河北省质监局应用微软Dot Net框架并采用C#语言技术、关系型数据库、三层的架构设计,建立了具有工作流自动判断、文件自动生成的行政事项网上申报审批系统,在实际应用中效果较好。

基于Dot Net平台的分布式应用程序架构设计

随着网络技术和企业信息化的发展,具有多层次性、面向对象型、跨平台性、系统功能易扩充、系统易维护、能适应大型的、复杂的应用等特点的分布式应用系统已得到了较为广泛的应用,本文着重探讨了基于Dot Net平台的分布式应用程序架构及系统设计方法。

Small but mighty:Empowering sodium/potassium-ion battery performance with S-doped SnO_(2) quantum dots embedded in N,S codoped carbon fiber network

SnO_(2) has been extensively investigated as an anode material for sodium-ion batteries(SIBs)and potassium-ion batteries(PIBs)due to its high Na/K storage capacity,high abundance,and low toxicity.However,the sluggish reaction kinetics,low electronic conductivity,and large volume changes during charge and discharge hinder the practical applications of SnO_(2)-based electrodes for SIBs and PIBs.Engineering rational structures with fast charge/ion transfer and robust stability is important to overcoming these challenges.Herein,S-doped SnO_(2)(S-SnO_(2))quantum dots(QDs)(≈3 nm)encapsulated in an N,S codoped carbon fiber networks(S-SnO_(2)-CFN)are rationally fabricated using a sequential freeze-drying,calcination,and S-doping strategy.Experimental analysis and density functional theory calculations reveal that the integration of S-SnO_(2) QDs with N,S codoped carbon fiber network remarkably decreases the adsorption energies of Na/K atoms in the interlayer of SnO_(2)-CFN,and the S doping can increase the conductivity of SnO_(2),thereby enhancing the ion transfer kinetics.The synergistic interaction between S-SnO_(2) QDs and N,S codoped carbon fiber network results in a composite with fast Na+/K+storage and extraordinary long-term cyclability.Specifically,the S-SnO_(2)-CFN delivers high rate capacities of 141.0 mAh g^(−1) at 20 A g^(−1) in SIBs and 102.8 mAh g^(−1) at 10 A g^(−1) in PIBs.Impressively,it delivers ultra-stable sodium storage up to 10,000 cycles at 5 A g^(−1) and potassium storage up to 5000 cycles at 2 A g^(−1).This study provides insights into constructing metal oxide-based carbon fiber network structures for high-performance electrochemical energy storage and conversion devices.

基于DotNet的快速开发框架Fastwork的设计与实现

介绍了一种基于Dot Net平台快速开发框架的设计和简单实现过程,探讨了如何运用Net技术进行框架业务逻辑层、数据访问层以及表示层的设计,并提出和简单实现了Fastwork快速开发框架。

Dot NET框架下Corn与ComGIS的发展对GIS软件组织方式的影响

为了与Java竞争，微软公司推出了DotNET和DotNET组件技术，DotNET组件技术比COM更加完善，微软公司也计划逐步用DotNET组件技术淘汰COM。在这一新的技术条件下，源于Microsoft的COM及以其为基础的ComGIS技术都在发生着巨大的变化。本文立足于项目开发中的实际经验，以商用大型GIS软件的最新发展成果为参考，对在DotNET框架下COM与ComGIS的发展进行了全面的分析，并以此为基础，分析了GIS软件组织方式受到的影响。

基于Unity3D的Dots寻路算法

自动寻路A*算法的时间复杂度和空间复杂度较高,且对资源消耗较大。通过在Unity3D引擎中结合Dots面向数据的技术堆栈技术,采用ECS+JOBS的工作模式,将过程多线程化,使用JobSystem+Job多线程运行逻辑,对自动寻路的A*算法进行改进,采用修改地图点密度的方法来降低计算量,性能节省非常明显。为了同时考虑性能问题和寻路表现,再次改进算法,根据寻路对象的个数来动态地改变点与点之间的间隔,并比较两种不同的方案触发寻路,选出最优方案,有效缩短寻路时间,项目可以稳定运行数千个实体角色。

Energy Levels of Strong Coupling Magnetopolaron in Quantum Dot

By using variational method of Pekar type, we have studied the energy levels of strong coupling magnetopolaron in disk shape quantum dot(QD) and quantum well(QW). Our results show that, with the increasing magnetic field and confinement strength, the magnetopolaron binding energy of QD and QW in the ground state and in the excited state is enhanced. The limiting results of bulk type and strict two dimensional type are obtained.

Size and Magnetic Field Dependence of Strong Coupling Magnetopolaron in Quantum Dot

By using the variational method of Pekar type, the ground state and the first excited state of the strong coupling magnetopolaron in cylinder shape quantum dot are considered. The results show that, with the increasing cyclotron frequency and the confinement strength, the magnetopolaron binding energies in both the ground state and the excited state, and the resonance frequency of magnetopolaron are enhanced. The limiting case of the bulk and strict one dimensional type is also discussed.

Two—Electron Energy Spectrum in a Parabolic Quantum Dot Under a Magnetic Field

Two interacting electrons in a harmonic oscillator potential under the influence of a perpendicular homo-geneous magnetic field are considered. The energies of two-electron quantum dots with the electron-LO-phonon couplingas a function of magnetic field are calculated. Calculations are made by using the method of few-body physics withinthe effective-mass approximation. Our results show that the electron-LO-phonon coupling effect is very important insemiconductor quantum dots.

Carbon dots regulate the interface electron transfer and catalytic kinetics of Pt-based alloys catalyst for highly efficient hydrogen oxidation

The regulation of interface electron-transfer and catalytic kinetics is very important to design the efficient electrocatalyst for alkaline hydrogen oxidation reaction(HOR).Here,we show the Pt-Ni alloy nanoparticles(PtNi_(2))have an enhanced HOR activity compared with single component Pt catalyst.While,the interface electron-transfer kinetics of PtNi_(2)catalyst exhibits a very wide electron-transfer speed distribution.When combined with carbon dots(CDs),the interface charge transfer of PtNi_(2)-CDs composite is optimized,and then the PtNi_(2)-5 mg CDs exhibits about 2.67 times and 4.04 times higher mass and specific activity in 0.1 M KOH than that of 20%commercial Pt/C.In this system,CDs also contribute to trapping H^(+)and H_(2)O generated during HOR,tuning hydrogen binding energy(HBE),and regulating interface electron transfer.This work provides a deep understanding of the interface catalytic kinetics of Pt-based alloys towards highly efficient HOR catalysts design.

Investigation on Exciton Relaxation Kinetics of ZnCulnS/ZnSe/ZnS Quantum Dots by Time-Resolved Spectroscopy Techniques

The exciton relaxation kinetics of ZnCuInS/ZnSe/ZnS quantum dots （QDs） is investigated by time-resolved spectroscopy techniques in detail. Based on the rate distribution model, the wavelength-dependent emission dynamics shows that the intrinsic exciton, the exciton in the interface defect state and that in donor-acceptor pair state （DAPS） together participate in the photoluminescence process of QDs, and the whole emission process is mainly dependent on the DAPS emission. Transient absorption data show that the intrinsic exciton and the interface defect species maybe together appear after excitation and the intensity-dependent Auger recombination process also exists in QDs at high excitation intensity.

Modulation of magnetic and electrical properties of bilayer graphene quantum dots using rotational stacking faults

Bilayer graphene quantum dots with rotational stacking faults(RSFs) having different rotational angles were studied.Using the first-principles calculation, we determined that these stacking faults could quantitatively modulate the magnetism and the distribution of spin and energy levels in the electronic structures of the dots.In addition, by examining the spatial distribution of unpaired spins and Bader charge analysis, we found that the main source of magnetic moment originated from the edge atoms of the quantum dots.Our research results can potentially provide a new path for producing all-carbon nanodevices with different electrical and magnetic properties.

Linear and Nonlinear Optical Absorptions of a Hydrogenic Donor in a Quantum Dot Under a Magnetic Field

The linear and nonlinear optical properties of a hydrogenic donor in a disc-like parabolic quantum dot in the presence of an external magnetic field are studied. The calculations were performed within the effective mass approximation, using the matrix diagonalization method and the compact density-matrix approach. The linear and nonlinear optical absorption coefficients between the ground （L =0） and the first excited state （L = 1） have been examined based on the computed energies and wave functions. We find that the linear, nonlinear third-order, and total optical absorption coefficients are strongly affected by the confinement strength of QDs, the external magnetic field, and the incident optical intensity.

Effect of the Electron—Phonon Coupling on Barrier D^— Quantum Dots in Magnetic Fields

The influence of the electron-phonon coupling on the energy of low-lying states of the barrier D- center, which consists of a positive ion located on the z-axis at a distance from the two-dimensional quantum dot plane and two electrons in the dot plane bound by the ion, is investigated at arbitrary strength of magnetic field by making use of the method of few-body physics. Discontinuous ground-state energy transitions induced by the magnetic field are reported. The dependence of the binding energy of the D- ground state on the quantum dot radius is obtained. A considerable enhancement of the binding is found for the D- ground state, which results from the confinement of electrons and electron-phonon coupling.

Effects of Impurity on the Ground—State Transitions of a Quantum Dot in Strong Magnetic Field

The low-lying spectra of parabolic quantum dots with or without an impurity at the center are investigated.While it has been known that the electron-electron interaction leads to ground-state transitions on magic values of angular momentum in a magnetic field. We show, in this paper, that the implantation of an impurity ion at the center can either enhance or suppress such transitions, depending on whether it is an acceptor or a donor ion.

Development of a quantum-dot-labelled magnetic immunoassay method for circulating colorectal cancer cell detection

AIM:To detect of colorectal cancer(CRC) circulating tumour cells(CTCs) surface antigens,we present an assay incorporating cadmium selenide quantum dots(QDs) in these paper.METHODS:The principle of the assay is the immunomagnetic separation of CTCs from body fluids in conjunction with QDs,using specific antibody biomarkers:epithelial cell adhesion molecule antibody,and monoclonal cytokeratin 19 antibody.The detection signal was acquired from the fluorescence signal of QDs.For the evaluation of the performance,the method under study was used to isolate the human colon adenocarcinoma cell line(DLD-1) and CTCs from CRC patients' peripheral blood.RESULTS:The minimum detection limit of the assay was defined to 10 DLD-1 CRC cells/mL as fluorescence was measured with a spectrofluorometer.Fluorescenceactivated cell sorting analysis and Real Time RT-PCR,they both have also been used to evaluate the performance of the described method.In conclusion,we developed a simple,sensitive,efficient and of lower cost(than the existing ones) method for the detection of CRC CTCs in human samples.We have accomplished these results by using magnetic bead isolation and subsequent QD fluorescence detection.CONCLUSION:The method described here can be easily adjusted for any other protein target of either the CTC or the host.

Simultaneous Effects of Hydrostatic Pressure and Conduction Band Non-parabolicity on Binding Energies and Diamagnetic Susceptibility of a Hydrogenic Impurity in Spherical Quantum Dots

Simultaneous effects of conduction band non-parabolicity and hydrostatic pressure on the binding energies of 1S, 2S, and 2P states along with diamagnetic susceptibility of an on-center hydrogenic impurity confined in typical GaAs/Alx- Ga1-x As spherical quantum dots are theoretically investigated using the matrix diagonalization method. In this regard, the effect of band non-parabolieity has been performed using the Luttinger-Kohn effective mass equation. The binding energies and the diamagnetic susceptibility of the hydrogenic impurity are computed as a function of the dot radius and different values of the pressure in the presence of conduction band non-parabolicity effect. The results we arrived at are as follows： the incorporation of the band edge non-parabolicity increases the binding energies and decreases the absolute value of the diamagnetic susceptibility for a given pressure and radius; the binding energies increase and the magnitude of the diamagnetic susceptibility reduces with increasing pressure.