MHD Thermal Stagnation Point Flow towards a Stretching Porous Surface

This paper presents an investigation of the hydromagnetic stagnation flow of an incompressible viscous, electrically conducting fluid, towards a stretching sheet in the presence of axially in- creasing free stream velocity. The Newton-Raphson shooting method along with the fourth-order Runge-Kutta integration algorithm has been employed to tackle the third order, nonlinear boundary layer equation governing the problem. The results indicate that suction and thermal Grashof number have the same effect on the rate of heat transfer. The magnetic parameter has the effect of increasing the skin friction coefficient whilst the reverse is observed for increasing the velocity ratio parameter. Keywords: Convective flow, Viscous, MHD, Free stream, Stagnation Point, Suction, Velocity Rati

Comparison of Long-Term Contracts and Vertical Integration in Decentralised Electricity Markets

Decentralised electricity systems require effective price and quantity risk management mechanisms but the nature of such systems poses particular problems for satisfying those requirements. Among these problems are investment hold-up risks rooted in the competition facing both electricity retailers and large industrial firms. Additional problems include those of load profile information and bargaining mismatches between generators and customers. Significantly hold-up risks exist not only between retailers and generators but also affect (e.g. fuel) suppliers upstream of generators. Contracts are one means of addressing such problems and represent a particular improvement on spot market trading alone. However we argue that market contracting in electricity systems is a costly approach to addressing hold-up and related problems and that internal organisation (i.e. vertical integration) is a more efficient alternative minimising the overall costs of market contracting and ownership. Not only does integration internalise wholesale market risks and market power costs to the integrated firm thereby reducing their importance it also reduces the need for and efficacy of regulation to constrain generator market power. It furthermore thins contract markets reducing the threat of generator hold-up from competitive retail entry and otherwise supports generation investment and hence supply security. While the reinstatement or retention of retail franchise areas is one possible solution to the problems of contracting it is arguably unnecessary if there are other system features (such as transmission constraints) impeding retail entry. This is particularly so in systems involving vertical integration although even then policy makers are confronted with a trade-off between promoting retail competition and facilitating generation investment and supply security requiring judgement as to the optimal degree of retail market power. While vertical integration is a more natural and self-sustaining solution to electricity sector problems it too is only a partial solution leaving complementary roles for spot and long-term contract markets

MHD Thermal Stagnation Point Flow towards a Stretching Porous Surface

This paper presents an investigation of the hydromagnetic stagnation flow of an incompressible viscous, electrically conducting fluid, towards a stretching sheet in the presence of axially in- creasing free stream velocity. The Newton-Raphson shooting method along with the fourth-order Runge-Kutta integration algorithm has been employed to tackle the third order, nonlinear boundary layer equation governing the problem. The results indicate that suction and thermal Grashof number have the same effect on the rate of heat transfer. The magnetic parameter has the effect of increasing the skin friction coefficient whilst the reverse is observed for increasing the velocity ratio parameter. Keywords: Convective flow; Viscous; MHD; Free stream; Stagnation Point; Suction, Velocity Rati

Technical Efficiency Analysis of Maize Farmers in the Eastern Region of Ghana

This study assesses the technical efficiency and its determinants of maize farmers in the Eastern Region of Ghana. A multi stage random sampling procedure was employed to select 226 maize farmers from the four main geographical areas of the region for the study. A well-structured questionnaire and field observations were employed to collect relevant information from the respondents. Data collected was analyzed using relevant econometric techniques. The results indicate that elasticities of mean output for agrochemicals, hired labor, other inputs are positive while those of seed, fertilizer and family labor are negative. The computed return to scale on the other hand reveals that, on average, the maize farms exhibit decreasing returns to scale. The joint effect of operational and farm-specific factors influence technical efficiency but individual effects of some variables are not significant. Mean technical efficiency level of the farmers is estimated to be 51%, indicating that the possibility of increasing maize production in the region given the current state of technology and inputs level can be achieved in the short run by increasing the technical efficiency level of the farmers by 49% through the adoption of practices of the best maize farmer. Further, the empirical results from the inefficiency model show that extension visit, FBO membership, frequency of meeting by members of FBOs, formal training in maize farming, cash and in-kind credits are the major determinants of the farmers’ technical efficiency level. Finally, the resource use efficiency results revealed that agro-chemicals and hired labor are under-utilized whereas seed, fertilizer and family labor are over-utilized by maize farmers in the region. These results have implications for management of small and medium scale food crop farms in developing countries

MHD Boundary Layer Flow due to Exponential Stretching Surface with Radiation and Chemical Reaction

The effects of radiation and first order homogeneous chemical reaction on hydromagnetic boundary layer flow of a viscous, steady, and incompressible fluid over an exponential stretching sheet have been investigated. The governing system of partial differential equations has been transformed into ordinary differential equations using similarity variables. The dimensionless system of differential equations was then solved numerically by the Runge-Kutta method. The skin-friction coefficient and the rate of heat and mass transfers are presented in tables whilst velocity, temperature, and concentration profiles are illustrated graphically for various varying parameter values. It was found that the rate of heat transfer at the surface decreases with increasing values of the transverse magnetic field parameter and the radiation parameter

Analysis of College Education Art Curriculum and Its Impact on Teacher Productivity at Primary Schools. The Case of Northern Ghana

This article examines the art curriculum at the colleges of education that prepares teachers at pre-service to teach creative art at the primary schools in Ghana with a focus on the northern region of the country. The study also assesses pupils’ knowledge and skills in the teaching and learning of creative art and reveals the teachers’ professional competencies of teaching creative art at the primary level. The article argues that the current teaching and learning of art as a subject at the primary schools requires improvement in the use of teaching and learning tools for effective classroom activities. Also, the quality of training received by teachers at pre-service is among factors that influence the current conditions of teaching and learning of creative arts at the primary level. The study reveals a mismatch in the relationship between the colleges of education curriculum and the basic school creative arts subject. The article suggests that the teacher training curriculum in creative arts that prepares teachers for Basic schools in Ghana and the Creative Arts syllabus for schools in Ghana are properly aligned in content knowledge. Adopting the qualitative and quantitative inquiry with descriptive and survey research methods, the instruments used for the data collection were questionnaire and interview. Keywords: Creative arts, art, curriculum, primary, college, education DOI: 10.7176/JEP/11-17-15 Publication date:June 30th 202

PENGARUH PENGELOLAAN KELAS TERHADAP DISIPLIN BELAJAR SISWA DI SEKOLAH MENENGAH KEJURUAN DAREL HIKMAH PEKANBARU

Penelitian ini bertujuan untuk mengetahui ada tidaknya Pengaruh Pengelolaan Kelas Terhadap Disiplin Belajar Siswa Di Sekolah Menengah Kejuruan Darel Hikmah Pekanbaru tahun ajaran 2012/2013 . Populasi dalam penelitian ini adalah siswa Sekolah Menengah Kejuruan Darel Hikmah Pekanbaru yang berjumlah 22 orang dari kelas XI. Variabel dalam penelitian ini adalah pengelolaan kelas sebagai variabel bebas (X) serta disiplin belajar sebagai variabel terikat (Y). Teknik pengambilan data yang digunakan adalah dengan menggunakan angket dan dokumentasi. Dalam penelitian ini data dianalisis dengan teknik Korelasi Product Moment. Hasil penelitian menunjukkan bahwa pengelolaan kelas memberikan kontribusi yang signifikan terhadap disiplin belajar siswa. Setelah menganalisis data, penulis menyimpulkan bahwa pengelolaan kelas ialah sebesar 63.6% atau pada kategori sedang, sedangkan disiplin belajar siswa ialah sebesar 68.2% atau pada kategori sedang. Melalui uji SPSS korelasi product moment, hasil analisis data penelitian menunjukkan nilai koefisien korelasi sebesar 0.993 pada taraf signifikansi 5% yaitu 5% 0.4230.537. Dengan demikian maka Ha diterima dan Ho ditolak. Kesimpulan dari penelitian ini yaitu ada pengaruh Pengelolaan Kelas Terhadap Disiplin Belajar Siswa Di Sekolah Menengah Darel Hikmah Pekanbaru. Dari hasil penelitian ini, diharapkan guru selalu meningkatkan keterampilan pengelolaan kelas untuk dapat menembuhkan disiplin siswa dalam belajar