IOSR-JAP   Volume-3 ~ Issue-4 ~ March–April 2013

Abstract: The concept of ferroic species, prototypic and ferroic point groups, and evaluation of faintness indices for all the zero wave number vibrational modes whose oversoftening causes ferroelectricity (or) ferroelasticity are given by Aizu [4]. Aizu has dealt with non-magnetic properties only. This paper determines the species and evaluates the indices of faintness for magneto-electric polarizability by considering grey group as prototypic point group. The basic faintness index of a magneto-electric polarizability is the smallest of the faintness indices with respect to the individual components of the magneto-electric polarizability tensors. The faintness indices range from 1 to 6 [5], whether it is = 1 (or) > 1 defines whether the magneto-electric polarizability is normal (or) faint.

Key Words: Axial vector, grey group, magneto-electric polarizability, polar vector

[1] S. Bhagavantham, (1966). "Crystal Symmetry and physical properties". Academic press, London, p. 167 – 172
[2] Bradley, C.J and Cracknell, (1972). "Mathematical theory of symmetry in solids". Clarendon press, Oxford, p. 570 – 572
[3] W.A. Wooster, (1973). "Tensors and group theory for the physical properties of crystals". Clarendon press, Oxford, p. 113 – 118
[4] Keitsiro Aizu.(1973). "Journal of the physical society of Japan". Vol. 35 p : 181-187 and 1704 – 1707
[5] K. Aizu. (1972). "Journal of the physical society of Japan". vol. 33 p : 1390

Abstract: This paper describes how Okumura Hata's model is chosen and optimized for urban outdoor coverage in the Code Division Multiple Access (CDMA) system operating in 800MHz UHF frequency band, South-south Nigeria. This optimized path loss model is based on the empirical measurements collected in the CDMA network focusing on the city centre of Benin, Edo state. It is developed by comparing the calculated path loss from collected measurements with the well-known path loss models within applicable frequency range of CDMA system, such as Hata, SUI, Lee, and Egli's Model. The Hata model was chosen as a reference for this optimized path loss model development based on the closest path loss exponent and smallest mean error as compared to the measured path loss. This optimized Hata model is implemented in the path loss calculation during the validation process. Thus, this optimized model is successfully improved and would be more reliable to be applied in the Nigeria CDMA system for urban path loss calculation in the 800MHz frequency band.

Key Words: propagation loss prediction, optimisation, Hata model, urban area

[1]. Boggia, G., Camarda, P. and D'Alconzo, A, Modelling of Call Dropping in Well-Established Cellular Networks. EURASIP Journal on Wireless Communications and Networking. 2007: 1-11
[2]. Manoj, K.R , Coverage Estimation for Mobile Cellular Networks from Signal Strength Measurement Ph.D thesis, Dept. of Eleectrical Engineering, University of Texas at Dallas,1999.
[3]. Saunders R.S and Belloul, B, Making Wireless Networks deliver. Ingenia of the Royal Academy of Engineering, issue 12, 2002, pp 36-40.
[4]. Rappaport, T.S, Wireless Communications Principles and Practice, Second Edition, Prentice Hall, Free Space Propagation Model, 2002, pp. 107-109.
[5]. Erceg,V. and Hari, K. V. S., Channel Models for fixed Wireless Applications. Tech. Rep., IEEE 802.16Broadband Wireless Access Working Grou, 2001.
[6]. Lee W.C.Y, Estimate of Local Average Power of a Mobile Radio Signal, IEEE Transactions. Vehicular. Technology, 34, 1985, 22-27.
[7]. Egli, J. J, Radio Propagation above 40 Mc over Irregular Terrain. Proc. IRE, pp.1957, 1383-1391
[8]. Mardeni, R. and Kwan, K. F, Optimisation of Hata propagation Prediction Model in Surban Area in Malaysia, Progress In Electromagnetics Research C, Vol. 13, 2010, 91-106.
[9]. Hata, M, Empirical formula for propagation loss in land mobile radio services, IEEE Transactions Vehicular. Technology, Vol. VT-29, No. 3, Aug. 1980, pp. 317– 325.
[10]. Lepaianen, J., and Manninmen, M., Radio Interface system planning for GSM /GPRS / UMTS. Boston: Kluwer Academic Publishers, 2001.

Abstract: This study investigates the profitability of small scale maize production in Niger state, using farm budgeting technique. Available reports on profitability studies in the state suggest little improvement among maize farmers inspite of massive investment in the sector by government. Data were collected using the multi-stage sampling technique, and administering structured questionnaires to a total of 200 randomly selected respondents from two LGAs of Niger State. Data collected were analyzed using descriptive statistics, net farm income analysis. The socio-economic characteristics of the respondents showed that 67% of the farmers were male, 76% were within the economically active age brackets, while 68% had non-formal education. The costs and returns analysis indicated that maize production was profitable with an average net farm income of N48, 109.00/hectare, and a gross ratio of 0.39; a production efficiency index (2.50) per farmer further adjudged the profitability of the enterprise, that is, the returns cover the cost of production almost three times. As maize is one of the most important staple foods of great socio-economic value in the study area, an improvement in the understanding of the level of profitability can greatly aid policy makers in enhancing policies that will promote profitability in production of the crop. In addition, improved access to farmlands, acquisition of formal education, improving rural financial markets and strengthening the existing extension services were recommended to improve profitability in maize production in the area.

Keywords: Maize, Small-scale, Profitability, Socio-economics, Niger state

[1]. Bernard, C. H. (2003). Economic Analysis of Cassava-based Cropping in Crude Oil Producing Area: A Case Study of River State Nigeria. Unpublished Ph.D Thesis, submitted to the Department of Agricultural Economics and Rural Sociology, Ahmadu Bello University Zaria, Nigeria. Pp 38-41.
[2]. Haruna, V. (2008). Economics of Cassava production in Jama‟a Local Government Area of Kaduna State: A Comparative Analysis of Local and Improved Varieties. An Unpublished M.sc.Thesis,submitted to Department of Agricultural Economics and Rural Sociology, Ahmadu Bello University Zaria.
[3]. Hill, D. J., Piggott, R.R and Griffith, G. R. (2001). Profitability of Incremental Generic Promotion of Australian Diary Products. Journal of Agricultural Economics. 26: 253- 266.
[4]. Ihenacho, SA.C. (2000). Economics of Millet Production Under Different Cropping Systems in Borno State, Nigeria.Unpublished Ph.D Thesis, submitted to Department of Agricultural Economics and Rural Sociology, Ahmadu Bello University Zaria. Pp 34-37.
[5]. IITA. (2007a). Maize. IITA Research to NourishAfrica.p.1.http://http://www.iita.org/cms/details/contactus.aspx
[6]. IITA. (2007b). Doubling maize production in Nigeria in two years.www.iita.org/cms/details/research summary.aspx.
[7]. IITA (2008). Increasing maize production in West Africa.http://www.iita.org/cms/details/newssummary.aspx
[8]. Jabo, M.S. M., Maikasuwa, M. A. and Mainasara, M. (2010). Costs and Returns Analysis of Cowpea Storage (Vigna Unguiculata) Using Chemical and non-Chemical Methods. In: Nmadu, J.N and Baba, K.M. (eds). Commercial Agriculture, Banking Reform and Economic Downturn: Setting a New Agenda for Agriculture Development in Nigeria. Proceedings of 11th Annual National conference of National Association of Agricultural Economists.Federal University of Technology, Minna, Nigeria.Pp 192-195.
[9]. Musa, S.A., Kyafi A.O., and Suleiman, M.S. (2010). Evaluation of Marketing Margin of Soya Beans in Kuje Area Council FCT Abuja, Nigeria. In: Nmadu, J.N and Baba, K.M. (eds). Commercial Agriculture, Banking Reform and Economic Downturn: Setting a New Agenda for Agriculture Development in Nigeria. Proceedings of 11th Annual National conference of National Association of Agricultural Economists.Federal University of Technology, Minna, Nigeria.Pp 152-157.