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The purpose of this paper is to explore the effects of the camber on gliding and hovering performance of two-dimensional corrugated airfoils. While the flying mechanism of natural flyers remains a myth up to nowadays, the simulation serves as a minor step toward understanding the steady and unsteady aerodynamics of the dragonfly flight.

The lattice Boltzmann method is used to simulate the flow past the cambered corrugated dragonfly airfoil at low Reynolds numbers. For gliding flight, the maximum camber, the distance of the location of maximum camber point from the leading edge and Reynolds number are regarded as control variables; for hovering flight, the maximum camber, the flapping amplitude and trajectory are considered as control variables. Then corresponding simulations are performed to evaluate the implications of these factors.

Greater gliding ratio can be reached by increasing the maximum camber of the dragonfly wing section. When the location of the maximum camber moves backward along the wing chord, large scale flow separation can be delayed. These two effects result in better gliding performances. For hovering performances, it is found that for different flapping amplitudes along an inclined plane, the horizontal force exerted on the airfoils increases with the camber, and the drag growths first but then drops. It is also found that the elliptic flapping trajectory is most sensitive to the camber of the cambered corrugated dragonfly wing section.

The effects of the camber on gliding and hovering performance of the cambered dragonfly wing section are explored in detail. The data obtained can be helpful when designing micro aerial vehicles.

Regulations to promote sanity in microfinance institutions and improve their operational problems yielded some results but lacked equal voice for effective implementation for its full realization. Much therefore has not changed in sub-Sahara African countries, though various types of regulation for microfinance exist. The nature and implementation of such policies therefore matter more than their mere presence. This paper aims to evaluate the nature of microfinance financial policies, given their social nature and the dynamism of their operational environment, and explores factors mitigating effective implementation of microfinance policy in Ghana.

A structured questionnaire was used to obtain data from the management and other officials of 63 microfinance institutions, and the outcome was organized into graphs and tables for descriptive analysis.

The results identified adequate adapted prudential regulation for microfinance institutions, but the formulation process lacked user input and adequate supervision, hindering effective sector policy implementation. The author therefore recommends a more inclusive and participatory policy formulation approach, creation of information platform for complete microfinance data through semi-autonomous supervisory body for microfinance services and regular full stakeholder engagement.

Though the study is limited to tier-two microfinance institutions in Accra, it is evident that the results can be applied to the entire sector and across national borders because microfinance institutions exhibit similar or same characteristics.

This paper has not been submitted to or published by any other journal. The author certifies that the content of this paper is the product of his own work, and that other sources used in preparing this paper and their respective sources have been duly acknowledged.

Different types of wood (ash, oak and beech) have been activated by new activation method. The aim of this work is to study the effect of different types of wood on the physical and chemical properties of Ni/Pd coatings.

The wood was activated by ablation of the Pd target using pulsed laser deposition (PLD) technique. Different diagnostic techniques such as X-ray photoelectron spectroscopy (XPS), attenuated total reflection (ATR) spectroscopy and energy dispersed X-ray spectroscopy (EDS), in parallel with scanning electron microscopy (SEM) were used to achieve this goal.

The XPS technique confirmed that the highest concentration of Pd was found in the Pd/beech sample, which is associated to the texture of the beech wood substrate surface. EDS results confirmed the absence of any contamination related to electroless plating method. It is concluded that the wood morphology and its surface roughness play a conclusive role to obtain different quantity of metal by PLD and electroless plating methods.

Although several works have been performed to study the influence of substrates on the coated metals and away of the traditional methods in activating non-catalytic surface, in this paper, PLD method is used to obtain a good quantity of Pd distributed on the entire surface and inside the porous of the wood. This study could be considered as a step investigation for understanding the role of the wood substrate morphology on the physical and chemical properties of films. To our knowledge, there are no works of combining a coated Ni/Pd by electroless plating and PLD methods on wood.

First, the purpose of this paper is to develop some policies as an alternative scenario to increase the performance of the Indonesian dairy milk supply chain so it can fulfil the target of the government. Second, this study aims to find the best alternative scenario based on the performance resulted from the simulation.

The paper develops a system dynamics-based model by using six approaches, i.e. “population and consumption of dairy milk”, “national milk production”, “dairy cattle feed”, “dairy cattle population”, “profit gained by the dairy farmer”, and “government policy”.

There is no best scenario; however, the combined scenario can give the better condition to achieve the targets set by the government.

The limitations of this study include: the relationship between the levels of welfare of farmers and the desire being a dairy farmer is not modelled; the quality of milk is only determined by the content of fat and protein in one litre of milk, and the level of milk consumption per capita increases naturally without any intervention or policy from the government.

This study provides essential insights into the context of implementing the policies in the Indonesian dairy supply chain.

The research revealed that good policies scenario could be built after simulating and analysing the effect of each scenario on the performance of a dairy supply chain carefully.

This study does not test one policy in isolation. It simultaneously tests various combinations of policy that related to dairy cattle import, operational assistance for dairy cooperative and dairy farmer that may help maximise the performance of the Indonesian dairy milk supply chain.