Effect of humidity on transonic flow

An experimental investigation of the effects of humidity-induced condensation on shock/boundary-layer interaction has been conducted in a transonic wind-tunnel test. The test geometry considered was a wall-mounted bump model inserted in the test section of the wind tunnel. The formation of a λ-shape condensation shock wave was shown from schlieren visualization and resulted in a forward movement of the shock wave, reduced shock wave strength, and reduced separation. Empirical correlations of the shock wave strength and humidity/dew point temperature were established. For humidity levels below 0.15 or a dew point temperature of 268 K, the effect of humidity was negligible. The unsteady pressure measurements showed that if a condensation shock wave formed and interacted with a main shock wave, the flow becomes unsteady with periodic flow oscillations occurring at 720 Hz

Causes of Absenteeism and Dropout Among Girls in Secondary Schools in Bureti Sub County, Kenya

Education is an important aspect for overall development of every person irrespective of gender. In Kenya, thè girl child is faced with a number of challenges in thè process of her secondary school education. Such challenges might include  absenteeism and dropout rate which may lead to diminishing girl child participation in formal education. Determining factors affecting girl-child educationis a worthy cause. This study sought to investigate  the causes of absenteeism and dropout among the girls in secondary schools in Bureti Sub County.Survey research design was used in the study.  The target population of the study was 5541 girl students and 62 secondary school teacher counselors. The accessible population was360 girl students and 16 teacher counselors  in the study area. Stratified sampling techniquewas used to sample the accessible population. Piloting of the instruments was carried out to find out the content validity of the items. Cronbach Alpha coefficient was used to estimate the reliability of the SQ and CTQ, and was found to be 0.75 suggesting that the items had relatively high internal consistency. Data was analysed using descriptive statistics.The findings of the study may provide educational  policy makers with in- depth information on the factors that undermine the girl child’s education; and subsequently to the formulation of policies that could safeguard the girl child in the pursue of educational opportunities. Keywords: Education, Girl Child, Absenteeism, Dropou

Influence of Selected Econonic Factors on Girl child Participation in Secondary School Education in Bureti Sub county, Kenya

This study, carried out in Bureti  Sub County,  sought to investigate selected economic factors that affect girl child’s participation in secondary school education in Bureti Sub county. The sub county had 62 secondary schools of which 15 were girls’ schools while 30 were mixed secondary schools and 17 were boys’ schools. The entire sub county had a total population of 12250 students and 406 teachers. The target populations were 5541 Female students and 62 secondary school teacher counselors in thesub countyt. Descriptive Survey research design was used in this study.  A saniple of 360 female students and 16 teacher counselors were drawn from 15 girls’  schools and mixed secondary schools in thesub county using stratified sampling technique. Students and teachers’ questionnaires were used to collect therequired data from therespondents. Research Instruments were validated through pilot study and reliability of 0.75 was determined using theCronbach’s alpha procedure. Descriptive statistics; mean, frequencies and percentages were used to analyze thedata while Statistical Packages for Social Sciences (SPSS) program was used for analysis. From thestudy, it was established that themost common factors that affected girl child participation in secondary school education were parents’ level of income. These have led to a number of girls dropping out of school. As a recommendation, the govemment should aid education of the girl child through provision of bursaries as effort to ensure equal participation by all students irrespective of their gender.. Key words: Girl Child, Participation, Economic factors,Secondary school educatio

The Effect of Competition on the Financial Sustainability of Micro Finance Institutions in Cameroon

This study aimed at investigating the effect of competition on the sustainability of Microfinance Institutions (MFIs) in Cameroon. Secondary data collected from the market mix data set was used for the study. The Herfindhal-Hirschman Index (HHI) was used to estimate the concentration (competition) index for MFIs while the random effect model was used as the estimation technique based on the Hausmann test. The results showed that an increase in concentration had a negative and statistical significant effect on return on asset. The result implies that as competition in MFIs increases, financial sustainability also improves. Other results showed that staff productivity, outreach, capital adequacy had a positive effect on financial sustainability while portfolio at risk had a negative effect on financial sustainability. The study therefore advocates for policies that can promote an environment conducive for competition in order to encourage MFIs to adopt innovative strategies to remain sustainable. Keywords: Competition, Sustainability, MFIs, Cameroon JEL Classification: G21, L1, O1

The control problem in fluid mechanics

Control in Fluid Mechanics deals maily with the laminar-turbulent transition, the threshold of which is wanted to be either decreased or increased . This review article insists on the linear point of view, which reduces the problem to the control of linearized equation s in the neighbourhood of a solution of the complete set of equations . It shows that the method used in most of the published work s is in fact a pole placement method . It underlines also that in some cases, the control built on a linear basis may lead to a contro l that is robust in highly non-linear conditions .L'objet principal du contrôle en mécanique des fluides concerne la transition laminaire-turbulente, dont on souhaite soit avancer soit reculer le seuil. Cet article de revue insiste sur l'approche linéaire, laquelle consiste à n'essayer de contrôler que les équations linéarisées au voisinage d'un point de fonctionnement. Il montre que l'approche suivie se résume pour l'essentiel à du placement de pôles. Il montre également que certains contrôles conçus de cette façon sont robustes pour des perturbations finies, c'est-à-dire dans des conditions non linéaires

Pore-scale distribution of mucilage affecting water repellency in the rhizosphere

The hydraulic properties of the rhizosphere are altered by plants, fungi and microorganism. Plant roots release different compounds into the soil. One of these substances is mucilage, a gel which turns water repellent upon drying. We introduce a conceptual model of mucilage deposition during soil drying and its impact on the soil wettability. We hypothesized that as soil dries, water menisci recede and draw mucilage towards the contact region between particles where it is deposited. At high mucilage content, mucilage deposits expand into the open pore space and finally block water infiltration when a critical fraction of the pore space is occupied. To test this hypothesis, we mixed mucilage and particles of varying grain size, let them dry and measured the contact angle (CA) using the sessile drop method. Mucilage deposition was visualized by light microscopy imaging. Contact angle measurements showed a distinct threshold-like behavior with a sudden increase in apparent contact angle at high mucilage concentrations. Particle roughness induced a more uniform distribution of mucilage. The observed threshold corresponds to the concentration when mucilage deposition occupies a critical fraction of the pore space, as visualized with the microscope images. Particle roughness induced a more uniform distribution of mucilage. In conclusion, water repellency is critically affected by the distribution of mucilage on the pore-scale. This microscopic heterogeneity has to be taken into account in the description of macroscopic processes, like water infiltration or rewetting of water repellent soil

Willingness to Pay for Faecal Compost by Farmers in Southern Ghana

The use of faecal waste for agricultural production is practiced by farmers in most parts of Ghana. However, information about farmer acceptability and willingness to pay is not widely reported.  Using choice experiment, this study analyse willingness to pay for faecal compost by farmers in Ningo-Prampram and Shai-Osudoku in Southern Ghana. Data was collected from 200 randomly sampled farming households and analysed using basic and hybrid conditional logit models. Results show farmers’ marginal willingness to pay values of US$0.51 for packaging only, US$ 0.32 for labeling only and US$ 0.82 for packaging and labeling of 50kg faecal compost. Farmers` willingness to pay was significantly influenced by their knowledge on faecal waste re-use in agriculture and experience with use of animal manure. Product attributes such as price, packaging and labeling as well as farmer’s socio-demographic characteristics, such as monthly household income, household size and age also significantly influence farmers’ willingness to pay. Keywords: Choice Experiment, hybrid Conditional Logit, Faecal Compost, Ghan