id	keyword
american_scientific_journal-3996	energy
american_scientific_journal-3996	efficiency
american_scientific_journal-3996	use
american_scientific_journal-3996	model
american_scientific_journal-3996	environment
american_scientific_journal-3996	pls
american_scientific_journal-3996	research
american_scientific_journal-3996	system
american_scientific_journal-3996	information