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Software Engineering Research

How to Be Creative in Software Engineering Research

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Motivation:

You plan to do a software engineering research and want to make some minor authentic contributions.

Guidelines:

1. You may present a problem and corresponding existing solution using your own understanding.

A method to do this is to

  • Read papers and books about a concept (for example backpropagation or distributed transactions), then
  • Write down the concept and some related terminologies, then
  • Try explain the concept with examples using your speech, and
  • Record your presentation, then
  • Write down your transcript, then
  • Rephrase your transcript.

2. You may try to replicate an existing result. When doing this you may need to make minor changes due to specific technology or environment conditions. Then you can compare your result with the original result.

For example, you may compare your business workflows with existing business workflows to determine which solution may solve a specific problem faster or more reliable.

In case you do not make any minor changes, the replication process may also inspire you some technical ideas. You may get errors while replicating the result. Try to fix these errors and document your experience.

For example you may get errors when upgrading an existing system from Node.js 12 to Node.js 18, or when upgrading an existing deep learning model code from Python 3.9 to Python 3.11. Try to fix the errors, then document your inputs, errors and solution.

3. The core idea to be creative is to do something that you have not done before. You may use trial and error method but be sure that you have a hard unsolved problem first. Trying to search for partial solutions to a problem will inspire you some ideas which may be the starting point for your minor authentic contributions.

4. Each individual’s creativity will need to be developed over time rather than in accordance with any kind of set formula.

 

Operating Systems

How to Set File Permissions for WordPress on Ubuntu

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Motivation:

  • You have a WordPress instance on Ubuntu Nginx.
  • You want to ensure that only the Nginx process can access WordPress files.

Procedure:

  1. View current file owner and group:
ls -l /var/html

The root folder should be owned by www-data user. www-data is the user that web servers like Apache and Nginx on Ubuntu use by default for their normal operation.

2. Change file owner and group to www-data if necessary:

sudo chown -R www-data:www-data /var/html

3. Set minimum permissions for folders:

cd /var/html
sudo find . -type d -exec chmod 755 {} \; # directory permissions rwxr-xr-x

4. Set minimum permissions for files:

cd /var/html
sudo find . -type f -exec chmod 644 {} \; # file permissions rw-r--r--

5. Verify the changes:

ls -l /var/html
Web Application Development

How to Back Up and Restore IIS App Pool and Site Settings

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Motivation:

You want to back up and restore IIS app pool and site settings.

Solution:

1. Open Command Prompt (Admin) and execute commands below to export IIS app pool and site settings to XML files.

%windir%\system32\inetsrv\appcmd list apppool /config /xml > \\192.168.101.140\BCDR\WEBBC02\E\inetpub\apppools.xml
%windir%\system32\inetsrv\appcmd list site /config /xml > \\192.168.101.140\BCDR\WEBBC02\E\inetpub\sites.xml

2. Remove all existing IIS app pools and sites, then execute the command below to import IIS app pool and site settings from XML files.

%windir%\system32\inetsrv\appcmd list apppool /config /xml < \\192.168.101.140\BCDR\WEBBC02\E\inetpub\apppools.xml
%windir%\system32\inetsrv\appcmd list site /config /xml < \\192.168.101.140\BCDR\WEBBC02\E\inetpub\sites.xml
Learning English

Forget vs. Forget About

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Forget is a general word, forget about is more specific.

  • “I forgot my keys.“: Person forgot their keys, as in it was left somewhere, and the person doesn’t have it.
  • “I want to forget about my keys.“: Person would like to “un”know about its keys, or wants to bury the memories of it.
  • “I forgot that face.“: Person doesn’t remember how someone’s face looked like.
  • “I forgot about that face.“: Non-direct way of saying one doesn’t remember all the facial features – but not the entire face.
Operating Systems

How to Fix Firefox No Sound Issue

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Problem:

Your Firefox suddenly does not play any sounds.

You have tried uninstalling and reinstalling it but the problem still persists.

Quick Solution:

  1. Go to Windows Settings > Sound > Advanced Sound Options .
  2. Make sure Firefox is not muted or set to low volume.

Advanced Solution:

  1. Create a Firefox account and synchronize (make a backup of) your current settings.
  2. Uninstall Firefox using Windows Apps and features.
  3. Go to %APPDATA%\Mozilla and delete Firefox folder.
  4. Open regedit.exe, search for Firefox, and delete all the keys and values that can be found. This process will take some time. Just ignore any errors that may occur when some keys or values cannot be deleted.
  5. Restart your computer.
  6. Download Firefox offline installer.
  7. Install Firefox.
  8. Log in your Firefox account and restore your settings.

 

 

Operating Systems

How to Determine all Ports Opened by a Program in Windows

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Motivation:

You want to ensure that your server is not compromised by a program.

Solution:

1. Open cmd.exe and execute commands below. Note the program file name and one of its ports that you want to investigate further.

netstat -a -b

2. Execute the command below. Note the PID associated with the port that you are interested in.

netstat -ano -p tcp

3. Execute commands below. “1544” is the PID that you are interested in.

netstat -ano -p tcp |find "1544"

4. Open https://mxtoolbox.com/TCPLookup.aspx, and enter [your external IP:port], and click TCP Lookup button to check if a port is open from your server.

5. Go to your Firewall and block the port if it should not be open to the Internet.

Database Management Systems

How to Change SQL Server sa User’s Password

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Problem:

You are a Windows Administrator and you can log in SQL server instance. However you cannot access databases.
You want to log in the SQL server instance under sa user but you forget the sa user’s password.
You cannot the sa user’s password using SQL Server Management Studio.

Solution:

1. Open cmd.exe and execute commands below. Replace MSSQL$SQLEXPRESS with your SQL service name and localhost\SQLEXPRESS with your SQL instance.

net stop MSSQL$SQLEXPRESS
net start MSSQL$SQLEXPRESS /m"SQLCMD"
sqlcmd -S localhost\SQLEXPRESS

2. Type and press Enter for each line below.

ALTER LOGIN [sa] WITH DEFAULT_DATABASE=[master]
GO
USE [master]
GO
ALTER LOGIN [sa] WITH PASSWORD=N'Password@1234'
GO
exit

3. Open cmd.exe and execute commands below.

net stop MSSQL$SQLEXPRESS
net start MSSQL$SQLEXPRESS

4. Open SQL Server Management Studio and log in the SQL server using the sa account.

Operating Systems

How to Fix Windows Updates Issue

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Problem:

You were applying Windows updates to a Windows server and got an error with code 0x8007000d or 0x80073701. You tried restarting your server several times but it seemed that the problem still persisted.

0x80073701 = ERROR_SXS_ASSEMBLY_MISSING which means there are some system files are missing, which caused the update installation failure.

Solution:

1. Restart your server.

2. Open Command Prompt (Admin).

3. Execute the commands below.

net stop wuauserv
net stop bits
:: Removes all files from the directory
del /q C:\Windows\SoftwareDistribution\*
:: Recursively removes all nested directories
for /d %x in (C:\Windows\SoftwareDistribution\*) do @rd /s /q "%x"
net start bits
net start wuauserv
control update

4. Close the Command Prompt (Admin).

5. Install Windows updates.

6. Click Retry button if you encounter an error.

 

Web Application Development

How to Select a .NET Framework

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Motivation:

You need to select a .NET framework for your new project or for upgrading a legacy system.

However there are too many .NET framework branches so you are not sure which one is suitable with your need.

Guidelines:

You need to review the history of .NET framework and the differences among the various branches that include .NET Framework, ASP.NET Web Forms, ASP.NET MVC, .NET Core and .NET 6.

1. .NET Framework

The main purpose of .NET Framework is for building Windows Forms Applications.

  • .NET Framework 1.0 was released in 2002.
  • .NET Framework 2.0 was released in 2005.
  • .NET Framework 3.0 was released in 2006.
  • .NET Framework 3.5 was released in 2007.
  • .NET Framework 4.0 was released in 2010.
  • .NET Framework 4.5.2 was released in 2014.
  • .NET Framework 4.8.1 (the latest version) was released in 2022.
2. ASP.NET Web Forms

ASP.NET Web Forms was built on top of .NET Framework.

The main purpose of ASP.NET Web Forms is for building ASP.NET Web Forms Applications (multiple page web applications).

3. ASP.NET MVC

ASP.NET Web Forms does not follow MVC architecture pattern. Therefore MS built ASP.NET MVC.

ASP.NET MVC was built on top of .NET.

ASP.NET MVC is open-source software, apart from the ASP.NET Web Forms, which is proprietary.

The main purpose of ASP.NET MVC is for building ASP.NET MVC Applications (multiple page web applications based on MVC architecture pattern).

  • ASP.NET MVC 1.0 was released in 2009 (It was built on top of .NET Framework 3.5).
  • ASP.NET MVC 2.0 was released in 2010 (It was built on top of .NET Framework 4.0).
  • ASP.NET MVC 5 (the latest version) was released in 2022 (It was built on top of .NET Framework 4.8).
4. .NET Core

.NET Framework does not run on Linux or Unix and is proprietary. Therefore MS built .NET Core.

.NET Core runs on Windows, Linux and Unix, and is open-source software.

  • .NET Core 1.0 was released in 2016.
  • .NET Core 3.1 was released in 2019.
  • .NET Core then was renamed to just .NET in 2020 and .NET 5 was released in 2020. The .NET 4 name was not used to avoid name collision with .NET Framework.
  • .NET 8 (the latest LTS version) was released in 2023.

The main purpose of .NET Core or .NET is for building Windows Forms Applications, ASP.NET MVC Applications and Single Page Applications that run on Windows, Linux and Unix.

The ASP.NET Web Forms Application type was removed from .NET Core or .NET.

5. .NET 8

Currently (in 2024) MS supports 2 branches of .NET:

  • .NET Framework 4.8.1 (containing Windows Forms Applications, Web Forms Applications, and ASP.NET MVC Applications) and
  • .NET 8 (containing Windows Forms Applications, ASP.NET MVC Applications and Single Page Applications).

Both .NET Framework 4.8.1 and .NET 8 support building microservices.

6. ASP.NET
  • .NET is a developer platform made up of tools, programming languages, and libraries for building different types of applications.
  • ASP.NET is a .NET web framework. ASP.NET extends the .NET platform with tools and libraries specifically for building web apps. ASP.NET runs only on Windows.
  • ASP.NET Core is the cross-platform version of ASP.NET. ASP.NET Core runs on Windows, Linux, macOS, and Docker.
  • ASP.NET Core MVC is ASP.NET Core with UI components written in HTML, CSS, JavaScript and C#.
  • ASP.NET Core Razor Pages is ASP.NET Core with UI components written in HTML, CSS, JavaScript, Razor markup and C#.
  • ASP.NET Core Blazor is front-end web framework with code written in HTML, Razor markup and C#, and relies on a .NET runtime built with WebAssembly for client-server interactions.
7. Final thoughts

For a new system, you probably should use .NET 8 and ASP.NET Core.

For a legacy system, if you are using ASP.NET Web Forms then you may stick with .NET Framework 4.8.1. Otherwise you may upgrade your system to .NET 8 and ASP.NET Core.