Geodesics Using Mathematica

We describe surfaces and geodesics without assuming prior knowledge of differential geometry. This involves selecting and presenting basic definitions and theorems. Included in this discussion are definitions of surface, coordinate patch, curvature, geodesic, etc. This summary closes with a proof of the length-minimizing properties of geodesics. Examples of surfaces of constant gaussian curvature are given and plotted in Mathematica. We also describe geodesics on these surfaces and plot select examples

Application of Explosive Detection Systems Steps for Fielding

In this paper we have surveyed some steps regarding application and fielding of explosive detection systems. We discussed the characteristics of the system which must be considered when procuring it, in order to be sure that the system will fit our requirements and can be smoothly fielded. We reviewed some basic methods of risk assessment that can be used for any security field and, in particular, are applicable to the process of fielding an EDS. The risk assessment process must consider the scenario, the known existing threats and any new threats that have arisen or which could occur in the future, such as new explosive targets and new methods of delivery and use. The new threats, and the weaknesses of current systems and methods, need to be reviewed during the process of risk assessment and decision making for future R&D and purchase. In some cases, new threats need to be taken into account in the development process. An astute decision at this stage can provide very important benefits for a small investment. Quality assurance at the production company is based on the specification of the system that defines all the technical parameters. These should be recognized and agreed with the buyer because they are an important part of the implementation of the security system. The end-product quality is measured against them. The key technical characteristics have to be carefully determined and the technical specification very precisely defined to allow it to be a basic document for the purchase and fielding of the system. We mention the main parameters that should be defined by the customer during the process: the explosives that need to detected by system, the required sensitivity, maximum tolerable false alarm rate, throughput rate and cost. Privacy and health and safety issues may also need to be considered. During the purchase process, demonstration and field test and evaluation are conducted to ensure that development and production has met the requirements. At this stage too, the specification document is the key point of reference, defining the parameters and values that are to be checked. Finally, we describe some of the new threats that are emerging and how EDS might be developed to meet them.JRC.G.6-Sensors, radar technologies and cybersecurit

Explosive Detection Equipment and Technology for Border Security

This report contains a brief survey of Explosives Detection Technology,as it is applied for inspection of goods and passengers at borders, and explains the role of European legislation and the European Commission¿s research programs in this field. It describes the techniques of trace and bulk explosives detection that are in use, the latest techniques that are in development and the characteristics of explosives that are, or might be, used to provide a signature for exploitation in detection technology. References to academic reviews are included for those wishing to study the subject in greater depth. Some additional details are given concerning plastic and liquid explosives, which are a threat of particular current importance. The report also contains a brief account of relevant European trade, safety and security legislation, a description of recent policy initiatives and tables of related European Commission funded research projects. Contact details of commercial companies selling explosive detection products are also provided.JRC.G.6-Sensors, radar technologies and cybersecurit

Tax Credits and IDA Programs

Tax Credits and IDA Program

Brief Announcement: Asymmetric Mutual Exclusion for RDMA

In this brief announcement, we define operation asymmetry, which captures how processes may interact with an object differently, and discuss its implications in the context of a popular network communication technology, remote direct memory access (RDMA). Then, we present a novel approach to mutual exclusion for RDMA-based distributed synchronization under operation asymmetry. Our approach avoids RDMA loopback for local processes and guarantees starvation-freedom and fairness