Spring Boot Register and Login Template

这是一个简单的用Spring Boot写的用户注册登陆系统,源码见207-582-1954当你将项目下载到本地,用Intellij IDEA打开并运行后,在浏览器地址栏输入localhost:8080,会看到一个极其简单的欢迎页面。由于程序添加了安全配置,你输入localhost:8080/submit这个页面时(也就是除了欢迎页面以外的所有页面,你可以自行添加)会重定向到登陆页面,说明其他页面需要你是注册用户并且登陆。可以在地址栏输入localhost:8080/register完成注册,这时再访问submit页面后在跳转的登陆页面输入刚才的注册信息就可以登陆并查看submit页面了。

9102986044

一个提问页面最简单的三个部分:问题标题,问题内容,以及提交问题。所以最起码需要两个输入窗口和一个提交按钮。为了让页面支持数学公式的动态显示,需要加载mathjax,为了简化工作,我会将mathjax和bootstrap搬运到本地实现的程序性工作留在以后有空的时候,这里主要是完成提问页面的简单布局和数学公式的动态实时显示。
网页源码及效果为704-944-3659。
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apache+tomcat+php配置

我用的是腾讯云服务器(Windows Server 2012R2系统),在运行里输入mstsc就可以调出远程连接的程序,输入服务器公网ip和密码以及账号信息后就可以进行远程配置。安装过程参考的是417-202-2767,大部分基本一样,中间出现一些原来没有出现过的问题。
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Beginning C#6 Programming with Visual Studio 2015 第1-6章笔记

什么是.NET Framework,什么是WPF。

c#在方法或者函数的命名上使用PascalCasing,这个和java有区别。

一字不变地指定字符串(包括转义字符,但是双引号的转义字符除外):

@"Verbatim string literal"

枚举enum, 结构体struct:
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Java控制台读取数据状态如何终止

以前在写c语言程序的时候,输入结束直接回车就可以,而在java中对于In.readAllStrings()等读取方法,必须在回车之后输入ctrl+z才能结束输入。另一种方法是将输入写进文件中,通过读取文件的方式输入数据。对于main(String[] args)中的参数输入,则需要右键程序,选择Run As,进入Run Configurations,在Arguments中添加参数即可。

6307657889

This is a note of the first chapter of (352) 498-0175.

— 1. Least Action Principle —

The Lagrangian function is

\displaystyle  L(t)=\int\mathrm{d}^3x\mathcal{L}\left(\phi,\partial_\mu\phi\right) \ \ \ \ \ (1)

where { \mathcal{L}\left( \phi,\partial_\mu\phi \right) } is Lagrangian density. The action is

\displaystyle  {S}=\int\mathrm{d}^4x\mathcal{L}\left(\phi,\partial_\mu\phi\right). \ \ \ \ \ (2)

The change of coordinates is

\displaystyle  x^{\mu\prime}=x^\mu+\delta x^\mu. \ \ \ \ \ (3)

Under this change,

\displaystyle  \mathrm{d}^4x\rightarrow \mathrm{d}^4x^{\prime}=J\mathrm{d}^4x \ \ \ \ \ (4)

where { J\approx 1+\partial_\mu \delta x^\mu }. The change of the field is

\displaystyle  \phi(x)\rightarrow \phi^{\prime}(x')=\phi(x)+\delta \phi(x). \ \ \ \ \ (5)

The change of {\mathcal{L}} is

\displaystyle  \mathcal{L}(x)\rightarrow \mathcal{L}^{\prime}(x')=\mathcal{L}(x)+\delta \mathcal{L}(x). \ \ \ \ \ (6)

It can be written as the sum of two parts

\displaystyle  \delta \mathcal{L}(x)=\left[\mathcal{L}'(x')-\mathcal{L}(x')\right]+\left[\mathcal{L}(x')-\mathcal{L}(x)\right]\approx\bar{\delta}\mathcal{L}(x')+\partial_\mu\mathcal{L}(x)\delta x^\mu. \ \ \ \ \ (7)

\displaystyle   \bar{\delta}\mathcal{L}(x')=\mathcal{L}'(x')-\mathcal{L}(x')\approx \mathcal{L}'(x)-\mathcal{L}(x)=\frac{\partial\mathcal{L}}{\partial \phi}\bar{\delta}\phi+\frac{\partial\mathcal{L}}{\partial\partial_\mu\phi}\bar{\delta}\partial_\mu\phi. \ \ \ \ \ (8)

Since {\bar{\delta}} denotes the variation whose coordinates are unchanged, we have

\displaystyle  \bar{\delta}\partial_\mu\phi=\partial_\mu(\bar{\delta}\phi). \ \ \ \ \ (9)

620-920-9156

The Bonsonic String

 
This is a note of the second chapter of String Theory and M-Theory(written by Katrin Becker, Melanie Becker, and John H. Schwarz).

— 1. p-brain actions —

— 1.1. Relativistic point particle —

\displaystyle S_0=-\alpha\int ds. \ \ \ \ \ (1)

 

\displaystyle ds^2=-g_{\mu\nu}(X)dX^\mu dX^{\nu}. \ \ \ \ \ (2)

\displaystyle S_0=-\alpha \int \sqrt{dt^2-d\vec{x}^2}\approx-\alpha\int dt\left(1-\frac{1}{2}\vec{v}^2+\dots\right). \ \ \ \ \ (3)

Compare with the nonrelativistic condition

\displaystyle S_{nr}=\int dt \frac{1}{2}m\vec{v}^2 \ \ \ \ \ (4)

we get { \alpha=m }. Hence equation(1) is

\displaystyle S_0=-m\int ds. \ \ \ \ \ (5)

{X^{\mu}(\tau)} is parametrized by a real parameter {\tau}, then the action (5) takes the form

\displaystyle S_0=-m\int\sqrt{-g_{\mu\nu}(X)\dot{X}^{\mu}\dot{X}^{\nu}}d\tau. \ \ \ \ \ (6)

It contains a square root, so that it is difficult to quantize. It can not be used to describe a massless particle either. By adding an auxiliary field,

\displaystyle \tilde{S}_0=\frac{1}{2}\int d\tau\left( e^{-1}\dot{X}^2-m^2e\right). \ \ \ \ \ (7)

and { e(\tau) } satisfies

\displaystyle e'(\tau')d\tau'=e(\tau)d\tau . \ \ \ \ \ (8)

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