Sains Malaysiana 43(11)(2014): 1775–1779

Does Electro-sensing Fish Use the First Order Polarization Tensor for Object Characterization? Object Discrimination Test

(Adakah Ikan yang Mempunyai Elektro-penderiaan Menggunakan Tensor Pengutuban

Peringkat Pertama untuk Pencirian Objek? Ujian Pembezaan Objek)

TAUFIQK.A. KHAIRUDDIN^1,2* & W.R.B. LIONHEART¹

¹School of Mathematics, The University of Manchester, Oxford Road, Manchester M13 9PL

United Kingdom

²Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia

81310 Skudai, Johor, Malaysia

Diserahkan: 18 Mac 2013/Diterima: 3 April 2014

ABSTRACT

This paper extends the previous works to further explore the role of the first order polarization tensor in electro-sensing by the weakly electric fish specifically for object discrimination and characterization. The first order polarization tensor for few objects used in the considered experiment are calculated and discussed to identify whether there are other evidences to suggest that a weakly electric fish able to recognize the tensor when choosing or rejecting an object. Our findings in this study suggest that all fish during most of the experiments face difficulties to discriminate two objects when their first order polarization tensors are almost similar depending on the types of training given to them.

Keywords: Electrical conducting object; polarization tensor; weakly electric fish

ABSTRAK

Artikel ini membentangkan perbincangan lanjutan daripada kajian lalu untuk mengkaji dengan lebih mendalam peranan tensor pengutuban peringkat pertama elektro-penderiaan oleh ikan deria-elektro lemah dalam pencirian dan pembezaan objek. Tensor pengutuban peringkat pertama bagi beberapa objek yang digunakan dalam eksperimen yang dipertimbangkan telah ditentu dan dibincangkan dalam mencari bukti tambahan untuk menyokong dakwaan bahawa ikan deria-elektro lemah mampu mengenal tensor ini apabila menerima atau menolak sesuatu objek. Hasil kajian mendapati bahawa semua ikan dalam kebanyakan ujian mengalami kesukaran untuk membezakan dua objek apabila tensor pengutuban peringkat pertama bagi kedua-dua objek ini adalah hampir serupa bergantung kepada jenis latihan yang telah diterima oleh ikan-ikan tersebut.

Kata kunci: Ikan deria-elektro lemah; objek mengkonduksikan elektrik; tensor pengutuban

RUJUKAN

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*Pengarang untuk surat-menyurat; email: taufiq@utm.my