Editorial Preface

The following issue marks the fifth anniversary for the Walailak Journal of Science and Technology. In that time the journal has made great strides forward improving the service we provide to our authors and moving to online publication of all papers that appear in the journal for maximum impact. Papers are now authored by researchers from both national and international universities and the quality and diversity of the work that is published continues to improve. This has been reflected in the high impact factor that the journal has achieved in recent years reaching as high as the tenth best journal in Thailand according to the Thai Citation Index. At this time we would like to thank the various people who have contributed to the success of the Walailak Journal of Science and Technology in the last five years. These include our associate editors Asst. Prof. Dr. Chitnarong Sirisathitkul and Asst. Prof. Dr. Padungsak Suksa-ard and our manager Mr. Kosin Sirirak. Finally, and most particularly, we wish to thank all the referees who have patiently reviewed articles on behalf of the journal ensuring quality and originality in all published work. Without the hard work of all these experts the journal would not of risen so high in such a short time; our gratitude goes out to you all. Assoc. Prof. Dr. David J. Harding Editor of the Walailak Journal of Science and Technology