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Dewatering of anaerobic digested (AD) sludge containing waste-activated sludge (WAS) from enhanced biological phosphorus removal (EBPR) poses numerous challenges including poor dewaterability, struvite scale formation, and recycling of high N and P levels in the sludge liquor to the treatment process. A full-scale water reclamation facility was investigated to mitigate these problems by experimenting with direct dewatering of EBPR WAS, bypassing the AD step. The investigations experimented with various blends of AD primary sludge with undigested thickened WAS to achieve dewatering performance improvements and overall operational cost savings. Direct thickened WAS dewatering has had many positive impacts including enhanced sludge cake solids concentration, reduced chemical use for facility operations, reduced struvite scaling, reduced biogas conditioning media servicing, eliminated need for centrate treatment, recovered capacity of existing unit operations including anaerobic digesters, and eliminated several proposed capital improvement projects that were previously deemed necessary. Although bypassing of WAS to AD reduced total biogas production, the specific gas yield increased to meet all of the facility's biogas demands and minimized excess gas flaring. The overall biosolids production mass increased causing increased transportation costs for disposal and caused notable odors, both of which are being currently investigated. PRACTITIONER POINTS: Direct WAS dewatering bypassing anaerobic digestion yields operational and process benefits in an EBPR water resource recovery facility Dewatered cake solids were increased compared with combined primary and WAS anaerobic digestion and dewatering Nutrient loads in sludge processing returns streams and operational costs are reduced by direct WAS dewatering.

In 1993 a study looking at the impacts of HIV and AIDS on livelihoods was conducted in two districts in Zambia—Mpongwe and Teta. Twelve years later in 2005 a restudy of the same areas was undertaken. The aim was to understand what had happened to individuals and clusters in the intervening period in terms of their adaptability and resilience to HIV and AIDS, and to assess whether the “cluster,” or livelihood network methodology was an effective approach to explore the impact of AIDS on farming, livelihoods, and social change. Significant changes had occurred at meso and national levels; Mpongwe had become a district capital, agricultural subsidies had been removed, health services had been decentralized and ART was becoming more available. As predicted by the first study, in 2005 Mpongwe was experiencing the full-blown impact of AIDS. However, the most significant finding of the study, which the livelihoods network methodology helped to highlight, was how social units had adapted and how livelihoods had remained surprisingly resilient. In Teta, AIDS impacts had been much less and a shift back to more traditional farming systems was seen. Because the future holds an inevitable increase in shocks and stresses, with now climate change too, the study highlights the need for more creative and informed approaches for buttressing the social protection functions of livelihood networks.

The addition of a robot to a human team can be beneficial if the robot can perform important tasks, provide additional skills, or otherwise help the team achieve its goals. However, if the human team members do not trust the robot they may underutilize it or excessively monitor its behavior. We present an algorithm that allows a robot to estimate its trustworthiness based on interactions with a team member and adapt its behavior in an attempt to increase its trustworthiness. The robot is able to learn as it performs behavior adaptation and increase the efficiency of future adaptation. We compare our approach for inverse trust estimation and behavior adaptation to a variant that does not learn. Our results, in a simulated robotics environment, show that both approaches can identify trustworthy behaviors but the learning approach does so significantly faster.

This article describes: (1) some of the effects of HIV/AIDS on rural communities in cast and southern Africa (2) the indications for the development of such impacts in Uganda, Tanzania and Zambia over the medium term, noting similarities and differences between the three countries; (3) explores the policy implications of these findings; (4) presents a generalised response strategy.

In the previous two chapters, the production systems and economic situations of the poor, middle and leading case-study households have been examined, as have the social contexts in which the households are embedded. I have sought to show in these accounts how the resilience of both household economies and rural social organisation is under severe strain, in the face of environmental fluctuation and the policy pressures exerted by the state. For many poor households, most of their income comes from non-agricultural sources; for many middle and even leading farmers, agricultural production is subsidised by wage-income remittances; and for even leading farmers, the struggle to keep their production activities viable is perilous.

If misunderstanding and misrepresentation underlies official attitudes towards peasant livestock management strategies, much the same can be said of the government attitude towards the communal area economy as a whole. The subject of this chapter moves from land use to household production activities, and whereas in the previous chapter I juxtaposed the conflicting interpretations of state and peasantry, here my concern is solely to use the field research to examine how households survive.

This book examines the impact government policy has had on agrarian change in Zimbabwe’s peasant farming areas over the course of this century. My intention is to find a means of linking an analysis of past and present change with a practical interest in the future. Since such a task accords with the telos of critical theory, that of Jurgen Habermas has been used to inform the theory and method used in this study.1

In the previous two chapters, the production systems and economic situations of the poor, middle and leading case-study households have been examined, as have the social contexts in which the households are embedded. I have sought to show in these accounts how the resilience of both household economies and rural social organisation is under severe strain, in the face of environmental fluctuation and the policy pressures exerted by the state. For many poor households, most of their income comes from non-agricultural sources; for many middle and even leading farmers, agricultural production is subsidised by wage-income remittances; and for even leading farmers, the struggle to keep their production activities viable is perilous.

It has been argued that an analysis of social change ideally requires a theoretical framework which can be used to analyse the scope that people, as individuals or part of social collectivities, have to make their own world, within the context of the structural constraints they face. The unit of analysis in the previous chapter was the household. It was shown that even leading farmers are constrained in their ability to enhance the viability of their production by the resource limitations they experience. If individual households by themselves cannot significantly improve their positions, then the onus falls upon the organisations that structure communal area societies. Accordingly, my concern in the empirical component of this chapter is to analyse the capacity of the two societies I worked in for effective, coordinated action at this supra-household level.

Conflict over interpretations of how land is used and how it should be used has formed a major barrier to understanding between the peasantry and the state since the origin of the colonial state in Zimbabwe. In Chapter 2 I argued that the colonial state’s pursuit of technical development policies was influenced not only by the political ends the government wished to achieve, but also by the purposive rationalisation employed by the state. The white authorities acted collusively and coercively: only in the early 1960s was it briefly acknowledged that the peasantry might hold not only an alternative, but a credible view of the world.

Zimbabwe’s ninety-year colonial experience is one of a journey down the path of linguistically — and hence socially — transmitted prejudices of which Hans-Georg Gadamer writes. But this path, I shall argue, must be understood as the result not primarily of racial prejudices per se, but rather of the prejudiced belief of the new settlers in the superiority of their western material and technical culture. This chapter explains the importance of this distinction.

(1989). Technical development and peasant impoverishment: land use policy in Zimbabwe's Midlands Province. Journal of Southern African Studies: Vol. 15, Politics of Conservation in Southern Africa, pp. 287-305.