Consensus on Transaction Commit

The distributed transaction commit problem requires reaching agreement on whether a transaction is committed or aborted. The classic Two-Phase Commit protocol blocks if the coordinator fails. Fault-tolerant consensus algorithms also reach agreement, but do not block whenever any majority of the processes are working. Running a Paxos consensus algorithm on the commit/abort decision of each participant yields a transaction commit protocol that uses 2F +1 coordinators and makes progress if at least F +1 of them are working. In the fault-free case, this algorithm requires one extra message delay but has the same stable-storage write delay as Two-Phase Commit. The classic Two-Phase Commit algorithm is obtained as the special F = 0 case of the general Paxos Commit algorithm.Comment: Original at http://research.microsoft.com/research/pubs/view.aspx?tr_id=70

For Whom is the Rural Economy Resilient? Initial Effects of Drought in Western Sudan

This discussion piece addresses two recent debates: entitlement theory and the resilience of rural systems. The authors find that in western Sudan entitlement theory provides a specific and useful framework for understanding the nature of the crisis confronting the society. Arguments about the resilience of rural systems, however, need to be more closely examined and will depend on site-specific factors. The rural economy and society of western Sudan were not found to be resilient

Fast neutron effects on transistor scattering parameters

It has not been possible in the past to characterize a transistor or other semiconductor device with regard to its performance in a fast neutron (E\u3e10keV) environment when the device is operated at high (\u3e100 MHz) frequencies. Using the scattering (s-) parameter concept, which regards a device as a two-port black box , a full characterization of the trends in the neutron bombarded high-frequency performance of a typical transistor can be made. Scattering parameters are not only an accurate means of describing the high-frequency performance of any device, but are now reasonably easily measured with the advent on the market of reliable, highly accurate s-parameter test sets. Methods which exist to permit the rapid design of high-frequency transistor circuits, once the device scattering parameters are known, are reviewed. The effects of neutron bombardment on a high-frequency transistor amplifier are found to be generally enhancing, rather than degrading as expected, if the device is operating near or above the published minimum fT --Abstract, page i

Cotton Production in Burkina Faso: International Rhetoric versus Local Realities

Voices ranging from the editorial page of the New York Times to organizations such as Oxfam and the presidents of Burkina Faso and Mali have argued that U.S. cotton subsidies depress world cotton prices and hurt African farmers. These policies deny West African countries their comparative advantage in cotton, which they can produce more cheaply and with lower environmental impacts than farmers in the United States. Some have gone as far as phrasing this as a national security issue; editorials in the New York Times and the Wall Street Journal have suggested that removing subsidies would have a strong auxiliary benefit by defusing a potential source of “feverish anti-Americanism.”1 Unlike the United States, where large corporate farmers dominate production, small farmers grow cotton in West Africa. Small changes in cotton prices have significant implications for poverty rates in a region that is consistently ranked as the world’s poorest. A study undertaken by International Food Policy Research Institute researchers in Benin indicates that reductions in farm-level prices result in increases in rural poverty (Minot and Daniels 2002). The International Cotton Advisory Committee predicts that if the United States removed subsidies, cotton prices would increase between 6 and 11 cents per pound (ICAC, cited in Baffes 2004). While debates about international pricing policies and subsidies are extremely important for farmers in West Africa, they are not the only relevant debates regarding cotton production there. Local farmers in Burkina Faso have a distinctly different view of cotton affairs.2 Instead of concern over international battles over cotton prices, their concerns are decidedly local. For many farmers in Burkina Faso, cotton is the only way to become wealthy. While they would favor increases in world prices, they are troubled by how cotton policy is being implemented in Burkina Faso, particularly about government determinations of cotton prices, high levels of corruption in cotton marketing and transport, high levels of indebtedness and late payments to farmers. Farmers also highlighted the difficulty of fitting cotton—a crop that requires high levels of inputs, both chemical and labor—into a production system where labor is constrained and access to fertile land is declining. Finally, farmers are concerned about pesticide use. Pesticides, while used at nowhere near the levels typical of wealthier countries, affect environmental health in Burkina Faso because of how they are applied

Evolving Tenure Rights and Agricultural Intensification in Southwestern Burkina Faso

Popular and official representations of the environment in Burkina Faso present soils as fragile and potentially subject to catastrophic collapse in fertility. In the cotton growing zone of southwestern Burkina Faso, researchers and policy makers attribute changes in land cover and land quality to population growth. This paper presents evidence questioning the dominant population-degradation narrative as applied to Burkina. We find that farmers are intensifying their production systems. While population has led to land scarcity, farmers are responding to both the resulting uncertainty in land rights and reductions in soil quality by intensifying the production process. Investments are used both as a soil-building and a tenure-building strategy

Diminished Access, Diverted Exclusion: Women and Land Tenure in Sub-Saharan Africa

Increasing commercialization, population growth and concurrent increases in land value have affected women\u27s land rights in Africa. Most of the literature concentrates on how these changes have led to an erosion of women\u27s rights. This paper examines some of the processes by which women\u27s rights to land are diminishing. First, we examine cases where rights previously utilized have become less important; that is, the incidence of exercising rights has decreased. Second, we investigate how women\u27s rights to land decrease as the public meanings underlying the social interpretation and enforcement of rights are manipulated. Third, we examine women\u27s diminishing access to land when the actual rules of access change. While this situation may sound grim, the paper also explores how women have responded to reductions in access to land. They have mounted both legal and customary challenges to inheritance laws, made use of anonymous land markets, organized formal cooperative groups to gain tenure rights, and manipulated customary rules using woman-to-woman marriages and mother-son partnerships. These actions have caused women to create new routes of access to land and in some cases new rights

Land Tenure and Rental in Western Sudan

This paper reports on aspects of land tenure in western Sudan, especially the nature of tenure insecurity and the functioning of the land rental market. The active land rental market accounted for about one-third of cultivated land. Patterns of land rental transactions, and tests of the importance of insecurity in renting land, where the owner may not be able to reclaim land rented out, do not support the presumption that rental markets perform poorly. The role of the sheikh as administrator of village land, and the claims of large landowners to vast tracts, are, however, important political problems that must be resolved before attempts at rationalizing land tenure

Experimenter Bias Effect at Varying Levels of Motivation

This study examined the effects of experimenter motivation upon the experimenter bias effect on a person perception task. It was hypothesized that the experimenter bias effect would decrease as reward and threat of punishment increased. Thirty-five experimenters were randomly assigned to five treatment groups including a control group, two reward groups, and two punishment conditions. Each experimenter administered the photo task to two subjects. The results failed to support the experimental hypotheses

Local politics in the time of Turabi\u27s revolution: gender, class and ethnicity in western Sudan

In one small village in western Sudan local political struggles over power and resources are enmeshed in discursive struggles over representations of gender, ethnicity, class and community. Analysis of two specific conflicts illustrates this point. In one conflict over control of a village grain co-operative some villagers sought to exclude women, West African immigrants and the poor from participating in political decision-making. In a second conflict over a roadside market these same villagers, empowered by the divisive rhetoric and policies of the National Islamic Front regime, again mobilised dominant representations of class, gender and ethnicity in an attempt to prevent marginal groups from gaining economic advantage. In both cases, villagers translated national discourses in different ways, refracting ideology to meet their specific local interests. These conflicts and fractured discourses epitomise the process of civil breakdown that has marked the tenure of the NIF regime