Poverty and trade liberalization: empirical evidence from 21 African countries

The study investigated the possible nexus between trade liberalization and poverty in 21 African countries covering the period 2005–2014. The study deployed the following econometric tests: descriptive statistics; the correlation matrix and variance inflator; the panel unit root test; the pooled OLS technique; and the panel co-integration test (Johansen co-integration test). In order to confirm the robustness and validity of the regression model result, Ramsey RESET, cross dependence, autocorrelation and heteroscedasticity tests were conducted. The findings reveal that foreign direct investment and inflation rate had a positive relationship with the human development index while exchange rates and trade openness were negatively related to poverty level at the 5 percent level. The study recommended urgent policy measures aimed at revamping the poverty alleviation programmes. The study recommended that in a bid to diversify export market, developing countries should target other developing countries in the spirit of South–South cooperation. Such countries should also consider the joining or strengthening of regional economic integration. Incentives for production and human capacity building in the export-oriented sector should be emplaced. Social and economic policies are required to protect any country against the adverse effects of lowered trade barriers

A Framework for Semantics of UML Sequence Diagrams in PVS

This paper presents a framework for representing formal semantics of a subset of the Unified Modeling Language (UML) notation in a higher-order logic, more specifically semantics of UML sequence diagrams is encoded into the Prototype Verification System (PVS). The primary objective of our work is to make UML models amenable to rigorous analysis by providing their precise semantics. This approach paves a way for formal development of systems through a systematic transformation of UML models. This work is a part of a long-term vision to explore how the PVS tool set can be used to underpin practical tools for analyzing UML models. It contributes to the ongoing effort to provide mathematical foundation to UML notations, with the aim of clarifying the semantics of the language as well as supporting the development of semantically-based tools

SECURITY ISSUES IN ADAPTIVE DISTRIBUTED SYSTEMS Abstract

Adaptive Distributed Systems (ADSs) are distributed systems that can evolve their behaviors based on changes in their environments. In this work, we discuss security and propose security metrics issues in the context of ADSs. A key premise with adaptation of distributed systems is that in order to detect changes, information must be collected by monitoring the system and its environment. How monitoring should be done, what should be monitored, and the impact monitoring may have on the security mechanism of the target system need to be carefully considered. Conversely, the impact of implementation of security mechanism on the adaptation of distributed system is also assessed. We propose security metrics that can be used to quantify the impact of monitoring on the security mechanism of the target distributed system

Towards a formalization of UML Class Structure in PVS

The Unified Modeling Language (UML) is a language for specifying, visualizing and documenting object-oriented systems, and serves as a standard OO modeling notation. As the semantics of UML constructs is given informally in natural language, it is, for example, difficult to formally reason about correctness of a system design. Formal methods provide a rigor that is lacking in most of OO modeling notations in general and UML notations in particular. In this paper, we present a work done on the formalization of UML class diagrams. We assign formal semantics to UML class diagram using PVS specification language (PVS-SL) as underlying semantic foundation