Scale and Technical Efficiency of Islamic Banks in Sudan: Data Envelopment Analysis

This paper employs several efficiency measures and productivity changes using Data Envelopment Analysis (DEA) to investigate efficiency performance of Islamic banks in Sudan. Our results indicate, among twelve banks included in our sample only two banks, (the largest bank in the group which is government owned, and middle sized, private bank), score technical efficiency level (i.e. scale and pure technical efficiency). While the smallest bank in the group (private owned), score pure technical efficiency (i.e., managerial efficiency), but scale inefficient. This result adds additional evidence to the existing literature that ownership (government versus private) is not a constraint of managerial and scale efficiency but bank’s size is important factor for scale efficiency.DEA;Banks efficiency;scale efficiency

Technical efficiency analysis of banks in major oil exporting Middle East countries

This paper investigates efficiency performance of thirty six banks operating in Gulf Cooperation Council (GCC) countries during the period 2006-2008 . Our results indicate in general GCC banks showed considerable pure technical efficiency in the past three years with the year 2007 exhibit the most efficient year, as the number of pure technical efficient banks reached 33 percent of the total banks compared to 25 percent in 2008. The fall in technical efficiency in 2008 is due to simultaneous fall in pure technical efficiency and the scale efficiency. The output loss caused by scale inefficiency (fall of scale operations below optimum level) in 2008 is estimated 16 percent compared to 5 percent in 2007. Our results also indicate scale efficiency is inversely related to banks' size implying a major source of scale inefficiency in GCC banks is due to sub-optimal size of operations. It is also indicated in the paper that scale efficiency is inversely related to risk, implying effective risk management policies may also enhance scale efficiency.technical efficiency;scale efficiency;DEA

Variability in bulb shape of selected onion inbreds and their hybrids

Typescript (photocopy) Thesis (M.S.)--Iowa State University, 1964. Includes bibliography

A robust fault detection method of rolling bearings using modulation signal bispectrum analysis

Envelope analysis is a widely used method for bearing fault detection. To obtain high detection accuracy, it is critical to select an optimal narrowband for envelope demodulation. Fast Kurtogram is an effective method for optimal narrowband selection. However, fast Kurtogram is not sufficiently robust because it is very sensitive to random noise and large aperiodic impulses which normally exist in practical application. To achieve the purpose of denoising and frequency band optimization, this paper proposes a new fault detector based on modulation signal bispectrum analysis (MSB) for bearing fault detection. As MSB results highlight the modulation effects by suppressing stationary random noise and discrete aperiodic impulses, the detector developed using high magnitudes of MSB can provide optimal frequency bands for fault detection straightforward. Performance evaluation results using both simulated data and experimental data show that the proposed method produces more effective and robust detection results for different types of bearing faults, compared with optimal envelope analysis using fast Kurtogram

POWER SYSTEM STUDY ON INTEGRATING WIND AND PV POWER TO THE GRID SYSTEM

In the current century the demand of energy increased due to the industrial revolution and the high use of energy. PV and wind power were explored to meet the energy demand requirement. The objective of this research is to study and analyze the effects on the voltages and faults currents levels on the buses of the system when integrating wind and PV farms to the grid system. The grid system is IEEE industrial power system, modeling and simulation were implemented using DIgSilent software to perform power system studies of load flow and short circuit analysis on grid-connected at steady state condition to study the voltages and faults currents at the buses. From load flow analysis of PV integration to the industrial system, the voltage is improved at the Buses, the far the grid system from utility supply the more effective the improvement of Buses voltages. Integrating Wind farm to the grid system will affect on the voltage levels, increasing the power from the wind farm decreases the voltage on the system Buses. Short circuit analysis applied base on ANSI and IEEE standards and the comparison between the fault currents contribution of PV grid connected and wind grid connected system showed that the contribution of PV farm is higher than wind farm. The contribution is higher on the Buses near to the point of interconnection

Threshold dynamics in mathematical models for mosquito- and rodent-borne diseases with seasonality

The Ph.D. thesis investigates the impact of the periodicity of weather on the spread of malaria, Zika fever, and Lassa fever by applying non-autonomous compartmental population models with time-dependent (periodic) parameters. The dynamics of the system is characterized by the basic reproduction number ($\mathcal{R}_0$) of periodic compartmental models, defined as the spectral radius of an integral operator acting on the space of continuous periodic functions, and it has also been shown that the reproduction number is a threshold parameter with respect to disease extinction or persistence. Our aim is to show that the disease-free periodic solution of our newly established models is globally asymptotically stable if $\mathcal{R}_0 1$, there exists at least one positive $\omega$-periodic solution. We provide numerical studies and give examples to describe what kind of parameter changes might trigger the periodic recurrence of the disease

An exploratory study of teachers’ beliefs and practices regarding the class opening by teachers of Arabic to speakers of other languages (TASOL)

This study examined the beliefs of teachers of Arabic to speakers of other languages (TASOL) about class openings and the interplay between such beliefs and teacher’s in-class practices regarding class opening as the first introductory part of a lesson. A questionnaire of three parts was given to two groups of TASOL: the first group comprised 63 randomly selected teachers, to provide their beliefs in general about class opening. Observations and interviews were administered to the second group of teachers (30 observations and 10 interviews were conducted) to highlight the mentioned interplay. The investigated beliefs were inspired by similar studies and TBQ (Teacher Belief Questionnaire). The observation process involved using observation notes and an observation checklist by the researcher. Overall, the results of this study indicate that class opening beliefs of most participants suggest a realization of the importance of this part of the lesson. However, it also highlights that most teachers give priority to cognitive practices at the expense of affective ones recommended by the field. The study also sheds light on the convergence between teacher beliefs and practices as well the level of divergence, calling into question the widely held assumption that the latter is driven by the former. Index Terms—teachers’ beliefs, lesson planning, class opening practice, contextual factors