The Distributional Effects of Horticultural Export Value Chains among Smallholders In Southern Ghana

Increasing foreign exchange problems and deteriorating prices of traditional export commodities have led policy makers and donor agencies to seek diversification in export crop production. In Ghana, crops such as pineapples and mangoes appear promising because of their high labour intensity and the expanding demand for fruits in Europe. Notwithstanding, there is a possible trade-off between export and food crop production because of the possibility of resource re-allocation. So far the major concern of government has been the macro-economic growth in terms export earnings while the distributional effects and impacts on household food security remain under-investigated. The study focused on a household survey undertaken in the forest and coastal-savannah transition zones, where the farming system has undergone a transition from established food-crop farming for urban markets to an intensive production of horticultural products for export. Logistic regression and a semi-log function were used to estimate the determinants of household food availability and income respectively. Results show that households engaged in export horticulture are better-off than those which do not. Yet, the sole adoption of staple or export crop is not a sufficient condition for improving household food security. Household land endowment and income are fairly to strongly unequally distributed, with higher inequality observed among households engaged in the combined scenario. The paper concludes that linkages which allow simultaneous and reliably access to a range of resources and services – purchased farm inputs, symmetric market information and technological know-how are critical if smallholders are to survive in increasingly competitive global food markets.Agricultural and Food Policy, Consumer/Household Economics, Demand and Price Analysis, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, International Relations/Trade, Marketing, Productivity Analysis, Research and Development/Tech Change/Emerging Technologies,

Migrant Detention and the Inequities in Healthcare Access

Immigration removal centres (IRC) have been deployed by the government in an attempt to secure the nation’s borders. The normalisation of actions in the controlling of migration flows has been initiated by a perception placed on migrants as being a threat to the welfare and security of society and therefore “undeserving” as referred to by Foucault (2003). This research study aims to uncover and critique the political institutional structures that are placing undocumented migrants at health risk whilst going through the process of determining their residential and legal status. The findings of this research project indicate that equity ceases to exist at the point where border enforcement and the right to healthcare converge. There is a new penal system that is being constructed within immigration detention that has enabled the mechanisms of disempowerment of migrant detainees to be conceived. The analysis of this research project further reveals the perilous conditions of healthcare for migrants in UK’s IRCs and the characteristics of UK immigration policy in providing healthcare to detainees. This research study explores the nexus of neoliberalism and state power, whereby detainees, deprived of their liberty and rights, become sources of private profits. The withholding of healthcare, the weak implementation of rights and policies, the discretionary use of state power to overrule medical advice and health rights is evidenced in the construction of the “hostile environment”. Agamben’s concepts of the state of exception and the camp, Schmitt’s liberal legality and the social determinants of health (SDH) are used to explore how the hostile environment impacts on the accessing of healthcare for migrant detainees. Interviews with twelve former detainees and five service providers provide the empirical material at the heart of this research project. The practices relating to health and healthcare in immigration detention highlights how the camp paradigm extends beyond the walls of detention centres through expectations of other public services to do the work of border control. This strange combination of public and private sector responsibilities and interests, contradicts and causes tensions in doctors’ loyalties to the welfare of their patients and to the securitisation interest of the Home Office (HO), and other processes. Doctors are presented as advocates of patients, and of NGOs which use legal expertise regarding detainees’ rights to counter the detention system’s abusive obstruction of detainees’ access to health

Investigating the effectiveness of mathematics games on students' attitudes and learning environment

The primary focus of the present study was an evaluation of the effectiveness of games when used in college-level mathematics classes in the United Arab Emirates (UAE). A mixed-method approach involved surveys, interviews, observations of classes and narrative stories.As a first step, a sample of 352 students in 33 classes from three colleges in Abu Dhabi (the largest emirate in the UAE) responded to two surveys. The first, a modified version of the What Is Happening In this Class? (WIHIC) questionnaire, was used to assess students’ perceptions of the learning environment. Five of the seven WIHIC scales were selected for use in my study, namely, Student Cohesiveness, Teacher Support, Involvement, Cooperation and Equity. One scale, from the Constructivist Learning Environment Survey (CLES), Personal Relevance, was also added. The second survey, used to assess students’ attitudes, involved two scales: one to assess students enjoyment of mathematics classes (from the Test of Science-Related Attitudes (Fraser, 1981); and one to assess students’ academic efficacy (modified from the Jinks and Morgan’s (1999) Student Efficacy Scale). Both the WIHIC and attitude scales were modified to improve their suitability for use in the UAE and relevance to the present study, and then they were translated into Arabic.The data were analysed for the modified WIHIC and attitude scales to check their factor structure, reliability, discriminant validity, and the ability to distinguish between different classes and groups. In terms of the validity of modified WIHIC and attitude scales when used with college-level students in the UAE, the factor analysis results attested to the sound factor structure of each questionnaire. The results for each modified WIHIC and attitude scale for alpha reliability and discriminant validity for two units of analysis (individual and class mean) compared favourably with the results for well-established classroom environment instruments.A one-way analysis of variance (ANOVA) for each modified WIHIC scale was used to investigate its ability to differentiate between the perceptions of students in different classrooms. The ANOVA results suggested that students perceived the learning environments of different mathematics classrooms differently on the modified WIHIC scales. In general, the results provided evidence of the validity of the modified WIHIC in describing psychosocial factors in the learning environments of college-level students’ mathematics classrooms in the UAE.The sample of 352 students was also used to examine the strength and direction of associations between the six learning environment scales and the two attitudes scales using simple correlation and multiple regression analyses. There was a statistically significant simple correlation between each attitude scale (Enjoyment of Mathematics Lessons and Academic Efficacy) and each of the six WIHIC scales with the individual as the unit of analysis, but not with the class mean as the unit of analysis. Multiple regression analysis suggested that students’ enjoyment of their mathematics lessons was more positive in classrooms with greater Teacher Support, Cooperation and Personal Relevance, and that Academic Efficacy was higher in classes with more Personal Relevance.Eight of the 33 classes (n=90 students) were exposed to mathematics games. For these students, the effectiveness of the mathematics games was evaluated in terms of classroom environment and attitudes, as well as achievement. Pre-test–post-test differences were explored using a one-way multivariate analysis of variance (MANOVA) with repeated measures (using the student as the unit of analysis). The results suggest that there were statistically significant pre–post differences for three of the six WIHIC scales (namely, Teacher Support, Involvement and Personal Relevance), for both attitude scales, and achievement.In-depth qualitative data (from observations and interviews) provided information about the introduction and use of games in mathematics. The data were analysed to shed light on students’ interactions during the games and to triangulate and to clarify and explain students’ responses to the learning environment and attitude questionnaires. Analysis of the interviews suggested that the students generally enjoyed mathematics more when games were included in their lessons, and that the use of mathematics games had improved their feelings about how well they were performing in mathematics.A narrative, based on the classroom observations, was written to provide the reader with insights into the classrooms that were exposed to the mathematics games. The narrative describing students playing mathematics games suggested that, with the introduction of games in the classroom, students were given the opportunity to interact with each other and to explain and compare their solutions with those of their team-mates. Therefore, qualitative data obtained from students who experienced the use of mathematics games supported the quantitative findings concerning the effectiveness of games in mathematics classes.Finally, a two-way MANOVA with repeated measures on one factor was used to identify the differential effectiveness of using games activities in mathematics instructions for male and female students. The results suggested that, whereas Student Cohesiveness scores were similar for the pre-test, males’ perceived greater cohesiveness than did females for the post-test. Males’ perceptions of Student Cohesiveness improved, while female score deteriorated, during the use of games.The results of my study provide information about the effectiveness of Jeopardy!-type games in terms of the classroom learning environment and students’ outcomes (attitudes and achievement). Because teachers are often reluctant to use computer-based games in their mathematics classrooms, my study is significant as the results have the potential to encourage mathematics teachers to incorporate the use of computer-based games in their classrooms as a viable alternative pedagogical approach. In particular, this study provides valuable information that could help teachers in the UAE to improve their pedagogical practices. The results of this study have the potential to encourage educators, researchers and curriculum developers in the UAE to incorporate the use of computer-based games in the curriculum as a practical way to improve classroom environments and students’ attitudes and achievement

Prediction & Active Control of Multi-Rotor Noise

Significant developments have been made in designing and implementation of Advanced Air Mobility Vehicles (AAMV). However, wider applications in urban areas require addressing several challenges, such as safety and quietness. These vehicles differ from conventional helicopter in that they operate at a relatively lower Reynolds number. More chiefly, they operate with multiples of rotors, which may pose some issues aerodynamically, as well as acoustically. The aim of this research is to first investigate the various noise sources in multi-rotor systems. High-fidelity simulations of two in-line counter-rotating propellers in hover, and in forward flight conditions are performed. Near field flow and acoustic properties were resolved using Hybrid LES-Unsteady RANS approach. Far-field sound predictions were performed using Ffowcs-Williams-Hawkings formulation. The two-propeller results in hovering are compared with that of the single propeller. This enabled us to identify the aerodynamic changes resulting from the proximity of the two propellers to each other and to understand the mechanisms causing the changes in the radiated sound. It was discovered that there is a dip in the thrust due to the relative proximity of the rotors. Owing to this, there is also some acoustic banding above the rotors mainly because they operate at the same rotational rate. We then considered the forward flight case and compared it with the corresponding hovering case. This enabled us to identify the aerodynamic changes resulting from the incoming stream. By examining the near acoustic field, the far-field spectra, the Spectral Proper Orthogonal Decomposition, and by conducting periodic averaging, we were able to identify the sources of the changes to the observed tonal and broadband noise. The convection of the oncoming flow was seen to partially explain the observed enhancement in the tonal and BBN, compared to the hovering case. It is well known that High fidelity methods are critical in predicting the full spectrum of rotor acoustics. However, these methods can be prohibitively expensive. We present here an investigation of the feasibility of reduction methods such as Proper Orthogonal Decomposition as well as Dynamic Mode decomposition for reduction of data obtained via Hybrid Large-Eddy – Unsteady Reynolds Averaged Navier Stokes approach (HLES) to be used further to obtain additional parameters. Specifically, we investigate how accurate reduced models of the high-fidelity computations can be used to predict the far-field noise. It was found that POD was capable of reconstructing accurately the parameters of interest with 15-40% of the total mode energies, whereas the DMD could only reconstruct primitive parameters such as velocity and pressure loosely. A rank truncation convergence criterion \u3e 99.8% was needed for better performance of the DMD algorithm. In the far-field spectra, DMD could only predict the tonal contents in the lower- mid frequencies whiles the POD could reproduce all frequencies of interest. Lastly, we develop an active rotor noise control technology to reduce the in-plane thickness noise associated with multi-rotor Advanced Air Mobility Vehicles (AAMV). An actuation signal is determined via the Ffowcs-Williams-Hawking (FWH) formula. Two in-line rotors are considered and we showed that the FWH-determined actuation signal can produce perfect cancellation at a point target. However, the practical need is to achieve noise reduction over an azimuthal zone, not just a single point. To achieve this zonal noise reduction, an optimization technique is developed to determine the required actuation signal produced by the on-blade distribution of embedded actuators on the two rotors. For the specific geometry considered here, this produced about 9 dB reduction in the in-plane thickness noise during forward flight of the two rotors. We further developed a technology that replaces using a point actuator on each bladed by distributed micro actuators system to achieve the same noise reduction goal with significantly reduced loading amplitudes per actuator. Overall, this research deepens the knowledge base of multi-rotor interaction. We utilize several techniques for extracting various flow and acoustic features that help understand the dynamics of such systems. Additionally, we provide a more practical approach to active rotor noise control without a performance penalty to the rotor system

Prediction of Noise Associated with an Isolated UAV Propeller

The emergent field of interest in the Urban Air Mobility community is geared towards a world where aerial vehicles are commonplace. This poses the problem of the effects of the radiated noise. The present research presents an in-depth analysis of the noise generation mechanism of a propeller as a mode of propulsion of the said aerial vehicles. Numerical simulation utilizing a Hybrid Large-Eddy Simulation (LES) coupled with Unsteady Reynolds-Averaged Navier-Stokes (RANS) solver, is adopted on an isolated propeller modeled from the commercial DJI Phantom II 9450 propeller. The Spalart-Allmaras one equation turbulence model with rotation/curvature correction is used. The Farassat’s 1A formulation of the Ffowcs-Willams-Hawkings equations are used with an off-body permeable porous stationary control surface for far-field noise predictions. The current results are found to be in good agreement with several observations including the thrust generated, the unsteady flow structure, and the radiated far-field sound spectra and directivity. A deeper study into the contributing sources of the noise generation both on the propeller surface, as well as in the swirling wake flow is performed

The Role on Fixed Income in Pension Scheme Investment in Ghana: A Possible Adoption for the United States Economy

The paper investigates the role of fixed income in pension schemes investment in Ghana by specifically looking at the asset allocation and the initial investment required to make the scheme solvent in the future at a specified high probability after matching all liabilities in Ghana.Looking at the assets-only analysis of pension schemes without matching their liabilities, equity appears to be an attractive asset classes to invest in. However, considering asset-liability analysis, there is a general trend of asset allocation shifting from equities to bonds (specifically One-year bonds). Keywords: stochastic, asset-liability, fixed-income, investment, pensions DOI: 10.7176/RJFA/13-14-04 Publication date:August 31st 202

Modeling the relationships between perceptions about technology and attitudes toward computers

Over the past few years, the relationship between attitudes and behavior has been of a major interest to educators. Previous studies have found varying degree of associations between attitudes, behavioral intention and perceptions and corroborate the fact that attitudes influence patterns of behavior. As computer technology is becoming pervasive in the society, researchers have attempted to explore the links between individual's perceived ease of use, perceived usefulness and their intention to use the computer technology. A study was conducted in two higher education institution in the United Arab Emirates to find out students' intention to use computer technology employing the Technology Acceptance Model (TAM) by Reference [1] as a theoretical framework and Structural Equation Modeling as an analytical tool. The results revealed strong relationships between the students' attitudes toward computer and intention to use. This paper further reports the applicability of technology acceptance model and its robustness and generalizability in different research contexts

Influence of Teacher Support and Personal Relevance on Academic Self-Efficacy and Enjoyment of Mathematics Lessons: A Structural Equation Modeling Approach

The purpose of our study was to examine the effects of two psychosocial features of the classroom environment (teacher support and personal relevance) on college students’ academic self-efficacy and enjoyment of mathematics lessons. Data collected from 352 mathematics students attending three higher education institutions in the United Arab Emirates were used to validate the questionnaires and to investigate the hypothesized relationships. Structural equation modeling analysis suggests that teacher support and personal relevance are influential predictors of enjoyment of mathematics lessons and academic self-efficacy

Exchange rate dynamics and monetary integration in the EAC contries

A major challenge for most countries in Sub-Saharan Africa is the evaluation of the exchange rate. This is more so in the East African Community (EAC) where macroeconomic and exchange rate management has been in particular challenged by massive foreign aid inflows partly as a result of Heavily Indebted Poor Countries (HIPC) initiative and other debt reliefs. In addition; improved macroeconomic management in the last decade attracted both short and medium to long term inflows to the region, as foreign investors turn to developing and emerging economies for yield. In this paper we estimate the fundamental equilibrium exchange rate (FEER) model for all the countries in the EAC and we assess the convergence of existing exchange rate regimes in the EAC. Our main contribution is that this exercise may contribute as a useful background for the ultimate decision of which exchange rate management framework will best fit the region during the transition period to monetary union

Adoption, yield and profitability of tomato grafting technique in Vietnam

Theme: Families, Farms, FoodThis paper assesses the impact of AVRDC’s tomato grafting approach on yield and farm profitability in Lam Dong province and Red River Delta, Vietnam. Tomato grafting is advantageous to farmers suffering from soil-borne disease and abiotic stresses. However, there is scanty information on the extent of knowledge on adoption studies of tomato grafting technology in Vietnam. Based on a farm household survey conducted in August 2012, this paper provides detailed assessment of the adoption and profitability of introducing tomato grafting in the two study areas. Results indicate a 100% (n=225) adoption in Lam Dong province, and a 48% (n=36) adoption in the Red River Delta. The use of rootstock varieties differs in both locations to address location-specific agronomic challenges: tomato variety ‘Vimina’ (or HW7996) to address bacterial wilt (BW) problem, and eggplant EG203 variety in the Red River Delta to address both BW and waterlogging problem. Estimates from a Cobb-Douglas production function show that tomato grafting increases yield by 30% based. Marketable yield of grafted tomato was significantly larger (71.3 t/ha in Lam Dong Province and 75.0 t/ha in Red River Delta) than nongrafted (48.0 t/ha in Red River Delta). The benefit-cost ratio of grafted tomato production was higher compared to non-grafted due to increased yield and higher premium price. Nonetheless, further validation studies are required, considering the relatively small sample size in the Red River Delta and the high variability of some parameters.C.A. Genova, P. Schreinemachers, V. Afari-Sef