Institutions, sustainable land use and consumer welfare: the case of forest and grazing lands in northern Ethiopia

Land is an essential factor of production. Institutions that govern its efficient use determine the sustainability of this essential resource. In Ethiopia all land is publicly owned. Such an institutional setting is said to have resulted in the major degradation of Ethiopia's land resources and dissipation of the resource rent. An alternative to this is assigning a private property institution. In this paper, we examine the consumer welfare effects of a change in the institutional setting on communal forest and grazing lands, using a cross-section data set of 200 households in Northern Ethiopia. Findings suggest that changing the current institutional setting could indeed be welfare reducin

Numerical simulation and experimentation of pulsatile flows in axisymmetric arterial models

ABSTRACT NUMERICAL SIMULATION AND EXPERIMENTATION OF PULSATILE FLOWS IN AXISYMMETRIC ARTERIAL MODELS by TADESSE GEBREEGZIABHER December 2011 Co-advisors: 1. Dr. Emmanuel Ayorinde 2. Dr. Trilochan Singh Major: Mechanical Engineering Degree: Doctor of Philosophy The primary motivation for this dissertation is the fluid flow and structural response to unsteady blood flow in the human body. The research work is a synergistic merging of numerical simulation and experimentation. For the experiments, an all-encompassing, highly flexible experimental apparatus was designed and fabricated to facilitate a wide range of operating conditions, the range of which was chosen to accommodate mammalian cardiovascular system for both human and animal species. The parameters that were varied during the course of the experimentation include the frequency of the flow pulsation, tubular materials having various structural properties, and blockages of the tube cross sections to simulate the presence of plaque in arteries. The main outcome of the experimentation was a connection between the amplitude and frequency of the pulsations and the volumetric flow rate of the flowing fluid. Of equal importance is the extent of the response of the wall to the nature of the pulsating flow which was detected, located and characterized using a non-invasive acoustic emission equipment. The simulations that were performed represent a major advance over prior attempts to simulate pulsating flows in flexible- and rigid-walled tubes. That advance was embodied in the model that was used to characterize the flow. In most of prior studies, a particular flow regime was selected and used throughout the entire solution domain. This selection ignored the fact that flowing fluids passing through variable cross sections undergo changes of flow regime. In particular, a flow initiated in a relatively large upstream cross section may be laminar based on inlet conditions. However, as the fluid travels downstream and enters a constricted cross section, the laminar regime may undergo a transition and subsequently experience turbulence. The capability to accommodate all these flow regimes by a single model was first accomplished in this research. Of special relevance is that the capability to simulate the proper flow regime enabled a more realistic response of the bounding wall of the tube to the imposed pulsations. Comparisons were made between the experimental results and the predictions of the simulations for two purposes. One was to establish the ranges of applicability of the simulation model. The other established a body of archival-quality information based on confirming experimental and simulated results. Another unique contribution of this research is the determination of the presence of flow-induced acoustic emissions. The motivation for this part of this work is the development of a diagnostic tool to detect, locate, and characterize blockages in arterial models

Participation of the Ethiopian Police Contingent in the United Nations Peace Operations: Focus on the Role and Challenges

This research article delved the role and challenges of the Ethiopian police contingent in the United Nations peace operations. To this end, the author used socio-legal research method. Both primary and secondary data collections tools were employed. Key informant interview based on the mission experience were used to collect primary data. Secondary data critically reviewed relevant normative frameworks, standards, official reports, websites and other materials. The finding indicated that the Ethiopian police contingents are performing policing roles including crime prevention; strengthen administration and capacity of local police, restructure and reform of the host states police. Nevertheless, Ethiopia’s participation remains very low and even nonexistent in most of the peace operations. The finding also indicated that lack of normative and institutional arrangements are among the major challenges of the police contingent. This in particular includes lack of clear selection guideline of the police for mission, pre-deployment training deficiencies to the police candidates on mission language, driving skill and mission area courses and lack of well-established training centers. This in turn stalled the Ethiopian police not to significantly respond to the call for UNPOL peace operations. Hence, Ethiopia’s normative frameworks and institutional arrangements should be in line with the UNPOL legal and policy frameworks. In this regard, lessons ought to be drawn from Rwanda, Ghana and Nigeria. Keywords: United Nations Police (UNPOL), Peace Operation, Role, Challenges DOI: 10.7176/JAAS/76-02 Publication date:October 31st 202

Household Tree Planting in Tigrai, Northern Ethiopia: Tree Species, Purposes, and Determinants

Trees have multiple purposes in rural Ethiopia, providing significant economic and ecological benefits. Planting trees supplies rural households with wood products for their own consumption, as well for sale, and decreases soil degradation. We used cross-sectional household-level data to analyze the determinants of household tree planting and explored the most important tree attributes or purpose(s) that enhance the propensity to plant trees. We set up a sample selection framework that simultaneously took into account the two decisions of tree growers (whether or not to plant trees and how many) to analyze the determinants of tree planting. We used logistic regression to analyze the most important tree attributes that contribute to households’ tree-planting decisions. We found that land size, age, gender, tenure security, education, exogenous income, and agro-ecology increased both the propensity to plant trees and the amount of tree planting, while increased livestock holding impacted both decisions negatively. Our findings also suggested that households consider a number of attributes in making the decision to plant trees. These results can be used by policymakers to promote tree planting in the study area by trengthening tenure security and considering households’ selection of specific tree species for their attributes.tree plantin, tree species, tree attributes or purposes, sample selection, Tigrai, Ethiopia

Participation in Off-Farm Employment, Rainfall Patterns, and Rate of Time Preferences: The Case of Ethiopia

Devoting time to off-farm activities, while complementing agricultural incomes, may be constrained by labor availability and financial capacity. This paper assesses the importance of rainfall patterns, which condition the availability of agricultural labor, and financial constraints on off-farm employment decisions. Using panel data from Ethiopia, which include experimental rate-of-time preference measures, we found that these and rainfall are significant determinants off-farm employment. Rural development policies should take into account the financial capacity of households and the role of off-farm opportunities as safety nets in the face of weather uncertainty.off-farm employment, rainfall variability, reduced availability of water, rate-of time-preferences, multinomial logit, Ethiopia

Participation in Off-Farm Employment, Risk Preferences, and Weather Variability: The Case of Ethiopia

This article assesses the relative importance of risk preferences and rainfall availability on households’ decision to engage in off-farm employment. Devoting time for off-farm activities, while it helps households earn additional incomes, involves a number of uncertainties. Unique panel data from Ethiopia which includes experimentally generated risk preference measures combined with longitudinal rainfall data is used in the analysis. An off farm participation decision and activity choice showed that both variability and reduced availability of rainfall as well as neutral risk preferences increase the likelihood of off-farm participation. From policy perspective, the results imply that expanding off farm opportunities could act as safety nets in the face of weather uncertainty. In addition, policy initiatives geared towards encouraging income diversification through off farm employment need to address underlying factor that condition risk bearing ability of households.Off-farm employment, labor supply, rainfall variability/reduced availability, risk preferences, GLLAMM, Ethiopia, Labor and Human Capital, Q13, D81, C35, C93,

Inflation and Money Growth in Ethiopia: is there a Threshold Effect?

This study analyses money growth - inflation nexus in Ethiopia using annual datasets covering the period 1970-2009. This period was considered due to data limitations. A significant aspect of the study is that it tries to identify the optimal level of money growth using Two Regime Threshold Model. The result from the two-regime threshold model reveals that there is indeed a threshold effect in the relationship between money growth and inflation and the optimal level of money growth is estimated to be 17% which has an important policy implication. Here, money supply creates inflationary pressures only when it exceeds 17%. A percentage increase in money supply above this threshold value is expected to cause 1.47 percent increase in annual inflation indicating that monetary factors are valid sources of inflation in Ethiopia. The results imply keep the money growth below 17%. Hence, a specific monetary policy measures that could be envisaged is controlling broad money supply (M2).Inflation; money growth; two regime threshold model; Ethiopi