Essays on Development Policy and the Political Economy of Conflict

Electoral Rules and Leader Selection: Experimental Evidence from Ugandan Community Groups. Despite a large body of work documenting how electoral systems affect policy outcomes, less is known about their impact on leader selection. We study this by comparing two types of participatory decision making in Ugandan community groups: (i) vote by secret ballot and (ii) open discussion with consensus. Random assignment allows us to estimate the causal impact of the rules on leader types and social service delivery. Vote groups are found to elect leaders more similar to the average member while discussion group leaders are positively selected on socio-economic characteristics. Further, dropout rates are significantly higher in discussion groups, particularly for poorer members. After 3.5 years, vote groups are larger in size and their members save less and get smaller loans. We conclude that the secret ballot vote creates more inclusive groups while open discussion groups favor the already economically successful. Preparing for Genocide: Community Meetings in Rwanda. How do political elites prepare the civilian population for participation in violent conflict? We empirically investigate this question using data from the Rwandan Genocide in 1994. Every Saturday before 1994, Rwandan villagers had to meet to work on community infrastructure. The practice was highly politicized and, according to anecdotal evidence, regularly used by the political elites for spreading propaganda in the years before the genocide. This paper presents the first quantitative evidence of this abuse of the community meetings. To establish causality, we exploit cross-sectional variation in meeting intensity induced by exogenous weather fluctuations. We find that an additional rainy Saturday resulted in a five percent lower civilian participation rate in genocide violence. Selection into Borrowing: Survey Evidence from Uganda. In this paper, I study how changes to the standard credit contract affect loan demand and selection into borrowing, using a representative sample of urban micro enterprises, most with no borrowing experience. Hypothetical loan demand questions are used to test whether firm owners respond to changes in loans' contractual terms and whether take-up varies by firms' risk type and other firm owner characteristics. The results indicate that contracts with lower interest rates and less stringent collateral requirements attract less risky borrowers, suggesting that there is scope for improvement of standard financial contract terms. Credit Contract Structure and Firm Growth: Evidence from a Randomized Control Trial. We study the effects of credit contract structure on firm outcomes among small and medium sized firms. A randomized control trial was carried out to distinguish between some of the key constraints to efficient credit use connected to the firms' business environment and production function, namely (i) backloaded returns (ii) uncertain returns and (iii) indivisible fixed costs. Each firm was followed for the 1-year loan cycle. We describe the experiment and present preliminary results from the first 754 out of 2,340 firms to have completed the loan cycle. Firms offered a grace period have higher profits and higher household income than firms receiving a rebate later on as well as the control group. They also increased the number of paid employees  and reduced the number of unpaid employees, an effect also found among firms that received a cash subsidy at the beginning of the loan cycle. We discuss potential mechanisms behind these effects.

Recent advances in the development of tissue transglutaminase (TG2) inhibitors

Tissue transglutaminase (TG2) is a Ca2+-dependent enzyme and probably the most ubiquitously expressed member of the mammalian transglutaminase family. TG2 plays a number of important roles in a variety of biological processes. Via its transamidating function, it is responsible for the cross-linking of proteins by forming isopeptide bonds between glutamine and lysine residues. Intracellularly, Ca2+ activation of the enzyme is normally tightly regulated by the binding of GTP. However, upregulated levels of TG2 are associated with many disease states like celiac sprue, certain types of cancer, fibrosis, cystic fibrosis, multiple sclerosis, Alzheimer's, Huntington's and Parkinson's disease. Selective inhibitors for TG2 both cell penetrating and non-cell penetrating would therefore serve as novel therapeutic tools for the treatment of these disease states. Moreover, they would provide useful tools to fully elucidate the cellular mechanisms TG2 is involved in and help comprehend how the enzyme is regulated at the cellular level. The current paper is intended to give an update on the recently discovered classes of TG2 inhibitors along with their structure-activity relationships. The biological properties of these derivatives, in terms of both activity and selectivity, will also be reported in order to translate their potential for future therapeutic developments. © 2011 Springer-Verlag.

Development of an intelligent quality management system using fuzzy association rules

In order to survive in the increasingly customer-oriented marketplace, continuous quality improvement marks the fastest growing quality organization’s success. In recent years, attention has been focused on intelligent systems which have shown great promise in supporting quality control. However, only a small number of the currently used systems are reported to be operating effectively because they are designed to maintain a quality level within the specified process, rather than to focus on cooperation within the production workflow. This paper proposes an intelligent system with a newly designed algorithm and the universal process data exchange standard to overcome the challenges of demanding customers who seek high-quality and low-cost products. The intelligent quality management system is equipped with the ‘‘distributed process mining” feature to provide all levels of employees with the ability to understand the relationships between processes, especially when any aspect of the process is going to degrade or fail. An example of generalized fuzzy association rules are applied in manufacturing sector to demonstrate how the proposed iterative process mining algorithm finds the relationships between distributed process parameters and the presence of quality problems.

Public sector auditing in Fiji:tracing its development and expansion

This paper examines the processes of public sector auditing, and its influence in Fiji over the period 1874-2003. Analyses of historical documents indicate that there were four major themes that influenced expansion of traditional auditing into performance auditing. This paper examines these. It also provides insights into the development of accountability practices as a result of changes in the Auditor-General's role. Conclusions drawn from the analysis indicate that traditional public sector auditing in Fiji expanded in accountability terms, possibly driven by public pressure through the media and elected representatives.

Pragmatic approach to the development of robust real-time protocols

This research is concerned with the development of distributed real-time systems, in which software is used for the control of concurrent physical processes. These distributed control systems are required to periodically coordinate the operation of several autonomous physical processes, with the property of an atomic action. The implementation of this coordination must be fault-tolerant if the integrity of the system is to be maintained in the presence of processor or communication failures. Commit protocols have been widely used to provide this type of atomicity and ensure consistency in distributed computer systems. The objective of this research is the development of a class of robust commit protocols, applicable to the coordination of distributed real-time control systems. Extended forms of the standard two phase commit protocol, that provides fault-tolerant and real-time behaviour, were developed. Petri nets are used for the design of the distributed controllers, and to embed the commit protocol models within these controller designs. This composition of controller and protocol model allows the analysis of the complete system in a unified manner. A common problem for Petri net based techniques is that of state space explosion, a modular approach to both the design and analysis would help cope with this problem. Although extensions to Petri nets that allow module construction exist, generally the modularisation is restricted to the specification, and analysis must be performed on the (flat) detailed net. The Petri net designs for the type of distributed systems considered in this research are both large and complex. The top down, bottom up and hybrid synthesis techniques that are used to model large systems in Petri nets are considered. A hybrid approach to Petri net design for a restricted class of communicating processes is developed. Designs produced using this hybrid approach are modular and allow re-use of verified modules. In order to use this form of modular analysis, it is necessary to project an equivalent but reduced behaviour on the modules used. These projections conceal events local to modules that are not essential for the purpose of analysis. To generate the external behaviour, each firing sequence of the subnet is replaced by an atomic transition internal to the module, and the firing of these transitions transforms the input and output markings of the module. Thus local events are concealed through the projection of the external behaviour of modules. This hybrid design approach preserves properties of interest, such as boundedness and liveness, while the systematic concealment of local events allows the management of state space. The approach presented in this research is particularly suited to distributed systems, as the underlying communication model is used as the basis for the interconnection of modules in the design procedure. This hybrid approach is applied to Petri net based design and analysis of distributed controllers for two industrial applications that incorporate the robust, real-time commit protocols developed. Temporal Petri nets, which combine Petri nets and temporal logic, are used to capture and verify causal and temporal aspects of the designs in a unified manner.

Development and evaluation of an ion induced x-ray emission system for the analysis of light and medium weight elements

The present work describes the development of a proton induced X-ray emission (PIXE) analysis system, especially designed and builtfor routine quantitative multi-elemental analysis of a large number of samples. The historical and general developments of the analytical technique and the physical processes involved are discussed. The philosophy, design, constructional details and evaluation of a versatile vacuum chamber, an automatic multi-sample changer, an on-demand beam pulsing system and ion beam current monitoring facility are described.The system calibration using thin standard foils of Si, P, S,Cl, K, Ca, Ti, V, Fe, Cu, Ga, Ge, Rb, Y and Mo was undertaken at proton beam energies of 1 to 3 MeV in steps of 0.5 MeV energy and compared with theoretical calculations. An independent calibration check using bovine liver Standard Reference Material was performed.  The minimum detectable limits have been experimentally determined at detector positions of 90° and 135° with respect to the incident beam for the above range of proton energies as a function of atomic number Z. The system has detection limits of typically 10- 7 to 10- 9 g for elements 14

The development of hard real-time systems using a formal approach

Hard real-time systems are a class of computer control systems that must react to demands of their environment by providing `correct' and timely responses. Since these systems are increasingly being used in systems with safety implications, it is crucial that they are designed and developed to operate in a correct manner. This thesis is concerned with developing formal techniques that allow the specification, verification and design of hard real-time systems. Formal techniques for hard real-time systems must be capable of capturing the system's functional and performance requirements, and previous work has proposed a number of techniques which range from the mathematically intensive to those with some mathematical content. This thesis develops formal techniques that contain both an informal and a formal component because it is considered that the informality provides ease of understanding and the formality allows precise specification and verification. Specifically, the combination of Petri nets and temporal logic is considered for the specification and verification of hard real-time systems. Approaches that combine Petri nets and temporal logic by allowing a consistent translation between each formalism are examined. Previously, such techniques have been applied to the formal analysis of concurrent systems. This thesis adapts these techniques for use in the modelling, design and formal analysis of hard real-time systems. The techniques are applied to the problem of specifying a controller for a high-speed manufacturing system. It is shown that they can be used to prove liveness and safety properties, including qualitative aspects of system performance. The problem of verifying quantitative real-time properties is addressed by developing a further technique which combines the formalisms of timed Petri nets and real-time temporal logic. A unifying feature of these techniques is the common temporal description of the Petri net. A common problem with Petri net based techniques is the complexity problems associated with generating the reachability graph. This thesis addresses this problem by using concurrency sets to generate a partial reachability graph pertaining to a particular state. These sets also allows each state to be checked for the presence of inconsistencies and hazards. The problem of designing a controller for the high-speed manufacturing system is also considered. The approach adopted mvolves the use of a model-based controller: This type of controller uses the Petri net models developed, thus preservIng the properties already proven of the controller. It. also contains a model of the physical system which is synchronised to the real application to provide timely responses. The various way of forming the synchronization between these processes is considered and the resulting nets are analysed using concurrency sets.

Development of real-time process control systems using formal techniques

A major application of computers has been to control physical processes in which the computer is embedded within some large physical process and is required to control concurrent physical processes. The main difficulty with these systems is their event-driven characteristics, which complicate their modelling and analysis. Although a number of researchers in the process system community have approached the problems of modelling and analysis of such systems, there is still a lack of standardised software development formalisms for the system (controller) development, particular at early stage of the system design cycle. This research forms part of a larger research programme which is concerned with the development of real-time process-control systems in which software is used to control concurrent physical processes. The general objective of the research in this thesis is to investigate the use of formal techniques in the analysis of such systems at their early stages of development, with a particular bias towards an application to high speed machinery. Specifically, the research aims to generate a standardised software development formalism for real-time process-control systems, particularly for software controller synthesis. In this research, a graphical modelling formalism called Sequential Function Chart (SFC), a variant of Grafcet, is examined. SFC, which is defined in the international standard IEC1131 as a graphical description language, has been used widely in industry and has achieved an acceptable level of maturity and acceptance. A comparative study between SFC and Petri nets is presented in this thesis. To overcome identified inaccuracies in the SFC, a formal definition of the firing rules for SFC is given. To provide a framework in which SFC models can be analysed formally, an extended time-related Petri net model for SFC is proposed and the transformation method is defined. The SFC notation lacks a systematic way of synthesising system models from the real world systems. Thus a standardised approach to the development of real-time process control systems is required such that the system (software) functional requirements can be identified, captured, analysed. A rule-based approach and a method called system behaviour driven method (SBDM) are proposed as a development formalism for real-time process-control systems.

The production of clinical dextran using membrane processes

Clinical dextran is used as a blood volume expander. The British Pharmacopeia (BP) specification for this product requires the amount of dextran below 12,000 MW and above 98,000 MW to be strictly controlled. Dextran is presently fractionated industrially using ethanol precipitation. The aim of this work was to develop an ultrafiltration system which could replace the present industrial process. Initially these molecular weight (MW) bands were removed using batch ultrafiltration. A large number of membranes were tested. The correct BP specification could be achieved using these membranes but there was a significant loss of saleable material. To overcome this problem a four stage ultrafiltration cascade (UFC) was used. This work is the first known example of a UFC being used to remove both the high and low MW dextran. To remove the high MW material it was necessary to remove 90% of the MW distribution and retain the remaining 10%. The UFC significantly reduced the amount of dialysate required. To achieve the correct specification below 12,000 MW, the UFC required only 2.5 - 3.0 diavolumes while the batch system required 6 - 7. The UFC also improved the efficiency of the fractionation process. The UFC could retain up to 96% of the high MW material while the batch system could only retain 82.5% using the same number of diavolumes. On average the UFC efficiency was approximately 10% better than the equivalent batch system. The UFC was found to be more predictable than the industrial process and the specification of the final product was easier to control. The UFC can be used to improve the fractionation of any polymer and also has several other potential uses including enzyme purification. A dextransucrase bioreactor was also developed. This preliminary investigation highlighted the problems involved with the development of a successful bioreactor for this enzyme system.