DTKI: a new formalized PKI with no trusted parties

The security of public key validation protocols for web-based applications has recently attracted attention because of weaknesses in the certificate authority model, and consequent attacks. Recent proposals using public logs have succeeded in making certificate management more transparent and verifiable. However, those proposals involve a fixed set of authorities. This means an oligopoly is created. Another problem with current log-based system is their heavy reliance on trusted parties that monitor the logs. We propose a distributed transparent key infrastructure (DTKI), which greatly reduces the oligopoly of service providers and allows verification of the behaviour of trusted parties. In addition, this paper formalises the public log data structure and provides a formal analysis of the security that DTKI guarantees.Comment: 19 page

The Potential Economic Returns of Converting Agricultural Land to Forestry: An Analysis of System and Soil Effects from 1995 to 2009

peer-reviewedPrivate land owners have been responsible for the majority of annual afforestation in Ireland since the mid1990s, but planting rates have generally been declining since 2002. Although the decision to plant may be driven by a number of factors, the profitability of forestry as a landuse option should be an important driver and offer some insight into trends in afforestation rates. As farmers undertake most afforestation in Ireland it is important to account for the opportunity cost of lost agricultural income when analysing the financial outcome of planting. In addition, soil quality plays an essential role in dictating the productivity and profitability of both agriculture and forestry. This study examines the effects of soil quality and superseded agricultural system on the potential profitability of afforestation by farmers between 1995 and 2009. Data from the National Farm Survey were employed to identify the annual gross margins for six agricultural systems on six soil types that differ in terms of quality. The measures of soil quality were translated into potential yield classes for forestry using an existing productivity model and Teagasc’s Forest Investment and Valuation Estimator was employed to calculate the net present value of afforestation for each of the systems and soil types. The results demonstrate how the competitiveness of forestry as a landuse option is influenced by soil quality and superseded enterprise and how forestry has become more competitive with agricultural enterprises over the period of analysis.Department of Agriculture, Food and the Marin

Love Tales

https://digitalcommons.library.umaine.edu/mmb-vp/5964/thumbnail.jp

Resource Planning in Engineering Services Firms

We develop a model to enable engineering professional services firms to improve the management of their competitive resources, i.e., skilled engineers, to be better able to respond to customer demand. The model was informed by semistructured interviews with senior executives from engineering, information technology (IT) services and technical consulting firms. As a result, we capture many of the complexities associated with the resource planning process in the professional engineering services sector. In the resulting model, the key attributes of supply, demand, and operations constraints are identified. Based on information obtained from the interviews, a number of test firms are created.We then use these test firms to study the impact of various resource planning policies on firm performance. These policies include the skill mix and profile of skilled employees, limits on the number of concurrent projects to which an employee can be assigned, and policies governing employee cross-training and hiring. The impact of these policies is evaluated in terms of business metrics, such as the project completion rate and net revenue. Finally, our model is extended to capture a multiphase rolling planning horizon, where projects may span multiple phases with the goal of ensuring consistency in employee assignment to projects