Many shortcuts doesn't work

Shortcuts for opening a new terminal(ctrl+alt+t), volume up, volume down, turning the brightness up and down don't work. These shortcuts are set by default on settings. But they worked well before system upgrade(from Ubuntu gnome 14.04.1).
Model: Lenovo Y430P
Platform: x86_64
Base system: Ubuntu 14.04.2
Desktop environment: GNOME (Version 3.12.2)

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: evince 3.12.2-0ubuntu1~trusty2 [origin: LP-PPA-gnome3-team-gnome3-staging]
ProcVersionSignature: Ubuntu 3.13.0-46.77-generic 3.13.11-ckt15
Uname: Linux 3.13.0-46-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.7
Architecture: amd64
CurrentDesktop: GNOME
Date: Mon Mar 9 20:19:20 2015
InstallationDate: Installed on 2015-01-11 (56 days ago)
InstallationMedia: Ubuntu-GNOME 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
ProcEnviron:
 LANGUAGE=en_HK:en
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_HK.UTF-8
 SHELL=/bin/bash
SourcePackage: evince
UpgradeStatus: No upgrade log present (probably fresh install)