1. By WSH script

args = WSCript.Arguments.Count
If args<>3 Then
 wscript.echo "Usage:"
 wscript.echo "cscript //nologo ShutDownmachine.vbs /Machine:<machinename> /Admin:<Administrator> /Pwd:<password>"
Else
 set colNamedArguments = WSCript.Arguments.Named
 strMachineName = colNamedArguments.Item("Machine")
 strUserName = colNamedArguments.Item("Admin")
 strPassword = colNamedArguments.Item("Pwd") 
 Set objLocator = CreateObject("WbemScripting.SWbemLocator")

 Set objWBEMService = objLocator.ConnectServer(strMachineName, "root\cimv2", strUserName,strPassword)
 If err=0 Then
  Set cols=objWBEMService.ExecQuery("Select * from Win32_OperatingSystem")
  For each col in cols
   col.ShutDown
   wscript.echo strMachineName & " is going to shutdown..."
  Next
 Else
  wscript.echo "Failed to Connect machine" & strMachineName
 End If
End If


2.By Windows CommandLine if current user have administrative privilege on target machine

c:\>shutdown /s /m <machinename>   <cr>