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Italian Journal of Pure and Applied Mathematics ISSN 2239-0227 N° 30 – May 2013 Italian Journal of Pure and Applied Mathematics ISSN 2239-0227 EDITOR-IN-CHIEF Piergiulio Corsini Editorial Board Saeid Abbasbandy Antonino Giambruno Paolo Salmon Reza Ameri Furio Honsell Maria Scafati Tallini Luisa Arlotti James Jantosciak Kar Ping Shum Krassimir Atanassov Tomas Kepka Alessandro Silva Malvina Baica David Kinderlehrer Sergio Spagnolo Federico Bartolozzi Andrzej Lasota Stefanos Spartalis Rajabali Borzooei Violeta Leoreanu Hari M. Srivastava Carlo Cecchini Mario Marchi Marzio Strassoldo Gui-Yun Chen Donatella Marini Yves Sureau Domenico Nico Chillemi Angelo Marzollo Carlo Tasso Stephen Comer Antonio Maturo Ioan Tofan Irina Cristea M. Reza Moghadam Aldo Ventre Mohammad Reza Darafsheh Petr Nemec Thomas Vougiouklis Bal Kishan Dass Vasile Oproiu Hans Weber Bijan Davvaz Livio C. Piccinini Yunqiang Yin Mario De Salvo Goffredo Pieroni Mohammad Mehdi Zahedi Alberto Felice De Toni Flavio Pressacco Fabio Zanolin Franco Eugeni Vito Roberto Paolo Zellini Giovanni Falcone Ivo Rosenberg Jianming Zhan Yuming Feng Gaetano Russo F O R U M EDITOR-IN-CHIEF Alberto Felice De Toni Ivo Rosenberg Faculty of Engineering Departement de Mathematique et de Statistique Udine University Université de Montreal Piergiulio Corsini Via delle Scienze 206 - 33100 Udine, Italy C.P. 6128 Succursale Centre-Ville [email protected] Montreal, Quebec H3C 3J7 - Canada Department of Civil Engineering and Architecture [email protected] Via delle Scienze 206 - 33100 Udine, Italy Franco Eugeni [email protected] Dipartimento di Metodi Quantitativi per l'Economia del Territorio Gaetano Russo Università di Teramo, Italy Department of Civil Engineering and Architecture [email protected] Via delle Scienze 206 VICE-CHIEF 33100 Udine, Italy Giovanni Falcone [email protected] Dipartimento di Metodi e Modelli Matematici Violeta Leoreanu viale delle Scienze Ed. 8 Paolo Salmon 90128 Palermo, Italy Dipartimento di Matematica [email protected] Università di Bologna MANAGING BOARD Piazza di Porta S. Donato 5 Yuming Feng 40126 Bologna, Italy College of Math. and Comp. Science, Chongqing Three-Gorges University, [email protected] Domenico Chillemi, CHIEF Wanzhou, Chongqing, 404000, P.R.China Piergiulio Corsini [email protected] Maria Scafati Tallini Irina Cristea Dipartimento di Matematica Antonino Giambruno "Guido Castelnuovo" Furio Honsell Dipartimento di Matematica e Applicazioni Università La Sapienza Violeta Leoreanu via Archirafi 34 - 90123 Palermo, Italy Piazzale Aldo Moro 2 - 00185 Roma, Italy Elena Mocanu [email protected] [email protected] Livio Piccinini Furio Honsell Kar Ping Shum Flavio Pressacco Dipartimento di Matematica e Informatica Faculty of Science Via delle Scienze 206 - 33100 Udine, Italy The Chinese University of Hong Kong Norma Zamparo [email protected] Hong Kong, China (SAR) [email protected] James Jantosciak EDITORIAL BOARD Department of Mathematics Alessandro Silva Brooklyn College (CUNY) Dipartimento di Matematica Saeid Abbasbandy Brooklyn, New York 11210, USA "Guido Castelnuovo" Dept. of Mathematics, Imam Khomeini International University, [email protected] Università La Sapienza Ghazvin, 34149-16818, Iran Piazzale Aldo Moro 2 - 00185 Roma, Italy [email protected] Tomas Kepka [email protected] MFF-UK Reza Ameri Sokolovská 83 Sergio Spagnolo Department of Mathematics 18600 Praha 8,Czech Republic Scuola Normale Superiore University of Tehran [email protected] Piazza dei Cavalieri 7 - 56100 Pisa, Italy Tehran, Iran [email protected] [email protected] David Kinderlehrer Department of Mathematical Sciences Stefanos Spartalis Luisa Arlotti Carnegie Mellon University Department of Production Engineering and Management, Department of Civil Engineering and Architecture Pittsburgh, PA15213-3890, USA School of Engineering Via delle Scienze 206 - 33100 Udine, Italy [email protected] Democritus University of Thrace [email protected] V.Sofias 12, Prokat, Bdg A1, Office 308 Andrzej Lasota 67100 Xanthi, Greece Krassimir Atanassov Silesian University [email protected] Centre of Biomedical Engineering, Bulgarian Academy of Science Institute of Mathematics BL 105 Acad. G. Bontchev Str. Bankova 14 Hari M. Srivastava 1113 Sofia, Bulgaria 40-007 Katowice, Poland Department of Mathematics and Statistics [email protected] [email protected] University of Victoria Victoria, British Columbia Malvina Baica Violeta Leoreanu V8W3P4, Canada University of Wisconsin-Whitewater Faculty of Mathematics [email protected] Dept. of Mathematical and Computer Sciences Al. I. Cuza University Whitewater, W.I. 53190, U.S.A. 6600 Iasi, Romania Marzio Strassoldo [email protected] [email protected] Department of Statistical Sciences Via delle Scienze 206 - 33100 Udine, Italy Federico Bartolozzi Mario Marchi [email protected] Dipartimento di Matematica e Applicazioni Università Cattolica del Sacro Cuore via Archirafi 34 - 90123 Palermo, Italy via Trieste 17, 25121 Brescia, Italy Yves Sureau [email protected] [email protected] 27, rue d'Aubiere 63170 Perignat, Les Sarlieve - France Rajabali Borzooei Donatella Marini [email protected] Department of Mathematics Dipartimento di Matematica Shahid Beheshti University Via Ferrata 1- 27100 Pavia, Italy Carlo Tasso Tehran, Iran [email protected] Dipartimento di Matematica e Informatica [email protected] Via delle Scienze 206 - 33100 Udine, Italy Angelo Marzollo [email protected] Carlo Cecchini Dipartimento di Matematica e Informatica Dipartimento di Matematica e Informatica Via delle Scienze 206 - 33100 Udine, Italy Ioan Tofan Via delle Scienze 206 - 33100 Udine, Italy [email protected] Faculty of Mathematics [email protected] Al. I. Cuza University Antonio Maturo 6600 Iasi, Romania Gui-Yun Chen University of Chieti-Pescara, Department of Social Sciences, [email protected] School of Mathematics and Statistics, Via dei Vestini, 31 Southwest University, 400715, Chongqing, China 66013 Chieti, Italy Aldo Ventre [email protected] [email protected] Seconda Università di Napoli, Fac. Architettura, Dip. Cultura del Progetto Via San Lorenzo s/n Domenico (Nico) Chillemi M. Reza Moghadam 81031 Aversa (NA), Italy Executive IT Specialist, IBM Software Group Faculty of Mathematical Science [email protected] IBM Italy SpA Ferdowsi University of Mashhadh Via Sciangai 53 – 00144 Roma, Italy P.O.Box 1159 - 91775 Mashhad, Iran Thomas Vougiouklis [email protected] [email protected] Democritus University of Thrace, School of Education, Stephen Comer Petr Nemec 681 00 Alexandroupolis. Greece Department of Mathematics and Computer Science Czech University of Life Sciences, Kamycka’ 129 [email protected] The Citadel, Charleston S. C. 29409, USA 16521 Praha 6, Czech Republic [email protected] [email protected] Hans Weber Dipartimento di Matematica e Informatica Irina Cristea Vasile Oproiu Via delle Scienze 206 - 33100 Udine, Italy Department of Civil Engineering and Architecture Faculty of Mathematics [email protected] Via delle Scienze 206 - 33100 Udine, Italy Al. I. Cuza University [email protected] 6600 Iasi, Romania Yunqiang Yin [email protected] School of Mathematics and Information Sciences, Mohammad Reza Darafsheh East China Institute of Technology, Fuzhou, Jiangxi School of Mathematics, College of Science Livio C. Piccinini 344000, P.R. China University of Tehran Department of Civil Engineering and Architecture [email protected] Tehran – Iran Via delle Scienze 206 - 33100 Udine, Italy [email protected] [email protected] Mohammad Mehdi Zahedi Department of Mathematics, Faculty of Science Bal Kishan Dass Goffredo Pieroni Shahid Bahonar, University of Kerman Department of Mathematics Dipartimento di Matematica e Informatica Kerman, Iran University of Delhi, Delhi - 110007, India Via delle Scienze 206 - 33100 Udine, Italy [email protected] [email protected] [email protected] Fabio Zanolin Bijan Davvaz Flavio Pressacco Dipartimento di Matematica e Informatica Department of Mathematics, Dept. of Economy and Statistics Via delle Scienze 206 - 33100 Udine, Italy Yazd University, Yazd, Iran Via Tomadini 30 [email protected] [email protected] 33100, Udine, Italy [email protected] Paolo Zellini Mario De Salvo Dipartimento di Matematica Dipartimento di Matematica e Informatica Vito Roberto Università degli Studi Viale Ferdinando Stagno d'Alcontres 31, Contrada Papardo Dipartimento di Matematica e Informatica Tor Vergata, via Orazio Raimondo 98166 Messina Via delle Scienze 206 - 33100 Udine, Italy (loc. La Romanina) - 00173 Roma, Italy [email protected] [email protected] [email protected] Jianming Zhan Department of Mathematics, Hubei Institute for Nationalities Enshi, Hubei Province,445000, China [email protected] ITALIAN JOURNAL OF PURE AND APPLIED MATHEMATICS – N. 30-2013 i ITALIAN JOURNAL OF PURE AND APPLIED MATHEMATICS – N. 30-2013 ii ITALIAN JOURNAL OF PURE AND APPLIED MATHEMATICS – N. 30-2013 1 Italian Journal of Pure and Applied Mathematics ISSN 2239-0227 Web Site http://ijpam.uniud.it/journal/home.html Twitter @ijpamitaly https://twitter.com/ijpamitaly EDITOR-IN-CHIEF Piergiulio Corsini Department of Civil Engineering and Architecture Via delle Scienze 206 - 33100 Udine, Italy [email protected] Vice-CHIEF Violeta Leoreanu Managing Board Domenico Chillemi, CHIEF Piergiulio Corsini Irina Cristea Furio Honsell Violeta Leoreanu Elena Mocanu Livio Piccinini Flavio Pressacco Norma Zamparo Editorial Board Saeid Abbasbandy Antonino Giambruno Paolo Salmon Reza Ameri
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