An Exploratory Study of the Impact of Government Policies on the Development of Small and Medium Enterprises in Developing Countries

This paper explores the effects of government policies on the development of Small and Medium Enterprises in developing countries through the examination of the case of Nigeria. Many research studies reported that SMEs in Nigeria have not benefited from the policies formulated by the government. This paper investigates the impediments to manufacturing SMEs growth and the needed pre-requisite environment for SMEs to benefit from government specific policies. The study adopted a qualitative methodology depending on face to face interviews with 20 SME owners and/or managers in five of the six geographical arears of Nigeria, 20 bank managers in the capital city of Lagos and 20 government officials located in the federal capital city of Abuja. The study unveils unique contextually novel insights, including particularly the distinctive processes and different relationships related to lenders decision. The research findings are consistent with those reported by other scholars in the field, and confirm that government policies and support in the areas of technology, infrastructure and finance affects the performance of SMEs to a great extent in Nigeria

Near-Field Analysis of Terahertz Pulse Generation From Photo-Excited Charge Density Gradients

Excitation of photo-current transients at semiconductor surfaces by subpicosecond optical pulses gives rise to emission of electromagnetic pulses of terahertz (THz) frequency radiation. To correlate the THz emission with the photo-excited charge density distribution and the photo-current direction, we mapped near-field and far-field distributions of the generated THz waves from GaAs and Fe-doped InGaAs surfaces. The experimental results show that the charge dynamics in the plane of the surface can radiate substantially stronger THz pulses than the charge dynamics in the direction normal to the surface, which is generally regarded as the dominant origin of the emission

Modelo dinámico de crecimiento en altura para monte alcornocal (Quercus suber L.) españoles y tunecinos

Seven simple and advanced dynamic polymorphic functions were considered to develop a dominant height growth model for Spanish and Tunisian cork oak forests. Data from 115 stem analyses performed in two regions in each country were used to fit the equations. Parameter estimates were obtained using the Dummy variable method. Both numerical, graphical and biological consistency were used to compare alternative models. The dynamic equation finally selected was derived from the Hossfeld model by considering the shape parameter to be related to site productivity. An analysis of the dominant height growth patterns between the two countries indicated that the same dominant height growth model was valid for both countries. This dominant height growth model allows estimation of dominant height with a level of reliability of at least 83% from an age of 15 years for a prediction interval of less than 40 years.Para desarrollar un modelo de crecimiento en altura dominante para monte alcornocal en España y Túnez se han probado siete funciones polimórficas simples y dinámicas. Para ello se han utilizado datos procedentes de 115 análisis de troncos realizados en dos regiones distintas de cada país. Para estimar los parámetros se utilizó el método de las variables ficticias. Los modelos fueron comparados de forma numérica y gráfica. La ecuación dinámica finalmente seleccionada fue derivada a partir de la ecuación de crecimiento de Hossfeld considerando el parámetro de forma como relacionado con la productividad de la estación. El análisis del patrón que sigue el crecimiento en altura dominante en ambos países indica que el mismo modelo de crecimiento en altura dominante es valido para ambos países. Este modelo de crecimiento en altura dominante nos permite estimar la altura dominante con una fiabilidad de más de un 83% a partir de los 15 años para un periodo de predicción menor de 40 años

PATIENT EXPOSURE OPTIMISATION THROUGH TASK-BASED ASSESSMENT OF A NEW MODEL-BASED ITERATIVE RECONSTRUCTION TECHNIQUE

The goal of the present work was to report and investigate the performances of a new iterative reconstruction algorithm, using a model observer. For that, a dedicated low-contrast phantom containing different targets was scanned at four volume computed tomography dose index (CTDIvol) levels on a Siemens SOMATOM Force computed tomography (CT). The acquired images were reconstructed using the ADMIRE algorithm and were then assessed by three human observers who performed alternative forced choice experiments. Next, a channelised hotelling observer model was applied on the same set of images. The comparison between the two was performed using the percentage correct as a figure of merit. The results indicated a strong agreement between human and model observer as well as an improvement in the low-contrast detection when switching from an ADMIRE strength of 1-3. Good results were also observed even in situations where the target was hard to detect, suggesting that patient dose could be further reduced and optimised

Control Upstream Austenite Grain Coarsening during Thin Slab Casting Direct Rolling (TSCDR) Process

Thin-slab cast direct-rolling (TSCDR) has become a major process for flat-rolled production. However, the elimination of slab reheating and limited number of thermomechanical deformation passes leave fewer opportunities for austenite grain refinement, resulting in some large grains persisting in the final microstructure. In order to achieve excellent ductile to brittle transition temperature (DBTT) and drop weight tear test (DWTT) properties in thicker gauge high-strength low-alloy products, it is necessary to control austenite grain coarsening prior to the onset of thermomechanical processing. This contribution proposes a suite of methods to refine the austenite grain from both theoretical and practical perspectives, including: increasing cooling rate during casting, liquid core reduction, increasing austenite nucleation sites during the delta-ferrite to austenite phase transformation, controlling holding furnace temperature and time to avoid austenite coarsening, and producing a new alloy with two-phase pinning to arrest grain coarsening. These methodologies can not only refine austenite grain size in the slab center, but also improve the slab homogeneity

Investigation of Some Physical Properties of the Nanosized ZnO Prepared by the Coprecipitation Method

Zinc oxide (ZnO) nanoparticles have been fabricated via the coprecipitation method, where their structural, magnetic, thermal and optical properties have been investigated. The structural characteristics have been inspected through the X-ray diffraction patterns, particle size distribution, transmission electron microscopy, BET analysis, and Fourier transform Infrared spectroscopy, which confirm the nanostructure of the ZnO particles. The BET analysis confirms the mesoporous nature of the ZnO nanoparticles. The magnetic properties have been investigated by the vibrating sample magnetometer. The hysteresis (M-H) loop ensures the paramagnetic behavior of the ZnO nanoparticles. The measured thermal conductivity of the ZnO is about 0.2901 W/mK. The very low thermal conductivity value for the ZnO nanoparticles makes it an attractive contender for thermoelectric power applications. UV-vis Diffuse reflectance spectroscopy has been exploited to study the optical properties. The nano ZnO direct and indirect band gap energy determined using Tauc’s relation are 3.29 and 3.09 eV, respectively. The optical properties, high porosity, and specific surface area of the prepared nanosized ZnO particles make it a promising candidate for photocatalytic application

Mapping the distribution of photo-currents responsible for generation of terahertz pulses at semiconductor surfaces

Photo-excited charge carriers at semiconductor surfaces generate pulses of terahertz (THz) radiation. By mapping the spatial distribution of the THz radiation in the near-field and the angular emission pattern in the far-field, we link the THz generation process to the photo-current direction. We find that inplane carrier dynamics play an important role and can even be the dominant source of THz radiation