Resource requirements and speed versus geometry of unconditionally secure physical key exchanges

The imperative need for unconditional secure key exchange is expounded by the increasing connectivity of networks and by the increasing number and level of sophistication of cyberattacks. Two concepts that are information theoretically secure are quantum key distribution (QKD) and Kirchoff-law-Johnson-noise (KLJN). However, these concepts require a dedicated connection between hosts in peer-to-peer (P2P) networks which can be impractical and or cost prohibitive. A practical and cost effective method is to have each host share their respective cable(s) with other hosts such that two remote hosts can realize a secure key exchange without the need of an additional cable or key exchanger. In this article we analyze the cost complexities of cable, key exchangers, and time required in the star network. We mentioned the reliability of the star network and compare it with other network geometries. We also conceived a protocol and equation for the number of secure bit exchange periods needed in a star network. We then outline other network geometries and trade-off possibilities that seem interesting to explore.Comment: 13 pages, 7 figures, MDPI Entrop

The impact of shale pressure diffusion on 4D seismic interpretation

Shale typically has a low but non-negligible permeability of the order of nanodarcys (recognized an appreciated in production of unconventional resources), which could affect the magnitude and pattern of the pressure in conventional reservoirs over the lifetime of a producing field. The implications of this phenomenon for reservoir monitoring by 4D seismic can be significant, but depend on the geology of the field, the time-lines for production and recovery, and the timing of the seismic surveys. In this PhD thesis I developed an integrated workflow to assess the process of shale pressure diffusion and its elastic implications in the 4D seismic interpretation of four conventional reservoirs (three North Sea case studies and one from West Africa), with different geological settings (shallow marine and turbidites) and production mechanisms. To accomplish that, first, a detailed petrophysical evaluation was performed to characterize the overburden, intra-reservoir and underburden shales. Next, the simulation models were adjusted to activate the shale-related contributions, and then, applying simulator to seismic workflows, 3D and 4D synthetic seismic modelling were performed, for comparison with the observed seismic data and to establish the impact of the shale pressure diffusion in the elastic dynamic behaviour of the reservoir. This work also includes a case study where evaluation of shale pressure diffusion was integrated with geomechanical simulations to assess the propagation of time shifts and time strain in the overburden of a high pressure/high temperature reservoir under compaction, improving the understanding of the distribution and polarity of the observed seismic time strain. Fluid flow simulation results of this work indicate that activation of the shale improves the overall reservoir connectivity, enhancing model prediction (production history matched data). The fit to observed 4D seismic data was improved in all the field applications with a noticeable reduction (up to 6%) in the mismatch (hardening and softening signal distribution) for the models with active shales. In reservoirs where the saturation was very sensitive to changes in pressure, shale activation proved to impact strongly on the breakout and distribution of gas liberated from solution. Overall, this work found that inclusion of shale in the 3D and 4D reservoir seismic modelling can provide valuable insights for the interpretation of the reservoir’s dynamic behaviour and that, under particular conditions such as strong reservoir compartmentalization, shale pressure diffusion could be a significant process in the interpretation of the 4D seismic signature

Reforming the Reform: Public Health Policy in the Dominican Republic

Introduction: (First paragraph only) The Dominican Republic is located south of Florida and east of Cuba, on the Eastern side Hispaniola; on the western side is Haiti. The Republic operates as representative democracy, with a bicameral national congress comprised of a Senate with 32 members and a Chamber of Deputies that operates similarly to the United States House of Representatives. Elections are held every 4 years for the presidency, and government is formed through a coalition of the three major parties, the Dominican Liberal Party (PLD), the Dominican Reformist Party (PRD), and the Social Christian Reformist Party. The judiciary is based on the US model as of 1994, and the Supreme Court is comprised of 16 judges. Many of the country’s governmental institutions and organs are relatively nascent—most being incepted in the early 1990s—and as such it is critical to pay attention to these institutional shifts

The Effect of Haptic Feedback on Basic Social. Interaction within Shared Virtual Environments

This paper describes an experiment that studies the effect of basic haptic feedback in creating a sense of social interaction within a shared virtual environment (SVE). Although there have been a number of studies investigating the effect of haptic feedback on collaborative task performance, they do not address the effect it has in inducing social presence. The purpose of this experiment is to show that haptic feedback enhances the sense of social presence within a mediated environment. An experiment was carried out using a shared desktop based virtual environment where 20 remotely located couples who did not know one another had to solve a puzzle together. In 10 groups they had shared haptic communication through their hands, and in another group they did not. Hence the haptic feedback was not used for completing the task itself, but rather as a means of social interacting – communicating with the other participant. The results suggest that basic haptic feedback increases the sense of social presence within the shared VE

Information Theoretically Secure Enhanced Johnson Noise Based Key Distribution over the Smart Grid

The imperative need for unconditionally secure key exchange is caused by the increasing connectivity of networks and by the increasing number and level of sophistication of cyberattacks. Two concepts that are information theoretically secured are quantum key distribution (QKD) and Kirchhoff-Law-Johnson-Noise (KLJN). However, these concepts require a dedicated connection between hosts in peer-to-peer (P2P) networks which can be impractical and/or cost prohibitive. A practical and cost effective method is to have each host share their respective cable(s) with other hosts such that two remote hosts can realize a secure key exchange without the need of an additional cable or key exchanger. We introduce a protocol for linear chain networks with a reconfigurable filter system to create non-overlapping single loops in the smart power grid for the realization of the Kirchhoff-Law-Johnson-(like)-Noise secure key distribution system. The protocol is valid for one-dimensional daisy chain networks (chain-like power line) which are typical of the electric distribution network between the utility and the customer. The speed of the protocol (the number of steps needed) versus grid size is analyzed. When properly generalized, such a system has the potential to achieve unconditionally secure key distribution over the smart power grid of arbitrary geometrical dimensions. In this work we also analyze the cost complexities of cable, key exchangers, and time required in the star network. We mention the reliability of the star network and compare it with other network geometries. We also conceived a protocol and equation for the number of secure bit exchange periods needed in a star network. We then outline other network geometries and trade-off possibilities that seem interesting to explore. We also propose a new key exchange trust evaluation for peer-to-peer sensor networks, where part of the network has unconditionally secure key exchange. As the utilization of sensor networks continues to increase, the importance of security becomes more profound. Many industries depend on sensor networks for critical tasks, and a malicious entity can potentially cause catastrophic damage. For a given sensor, the higher the portion of channels with unconditionally secure key exchange, the higher the trust value. We give a brief introduction to unconditionally secured key exchange concepts and mention current trust measures in sensor networks. We demonstrate the new key exchange trust measure on a hypothetical sensor network using both wired and wireless communication channels

en la mediana empresa Unión de Cooperativas de Cafés especiales Cordillera Isabelia R.L (U.C.C.E.I) del Municipio de Matagalpa, en el I semestre del año 2011

La evaluación del sistemacontable y de los procedimientos de Control Interno Administrativos y Financieros en La Unión de Cooperativas de Cafés Especiales Cordillera Isabelia R.L (UCCEI) del municipio de Matagalpa tiene el propósito de comprender de manera especifica el uso y aplicación de tales procedimientos de control al momento de ejecutar las operaciones de la entidad, así como también entender el manejo del registro del sistema contable que se utiliza con el fin de obtener una información financiera objetiva a través de la eficacia de las operaciones. El tema en estudio es de gran importancia ya que nos brinda una visión clara y precisa de las debilidades que día a día se pasan por alto en el transcurso del ejercicio económico, así como también los riesgos a que está expuesta la cooperativa y su manejo para evitar errores de magnitud que puedan afectar los estados financieros y su presentación. El buen funcionamiento de una entidad radica en la aplicación eficiente del control interno, además del uso eficaz de los sistemas contables. En UCCEI existen riesgos inherentes en las operaciones y en el registro adecuado de las transacciones las cuales deben su origen en la poca capacitación del personal fijo que labora en las instalaciones, además de esto el manual de control interno no se actualiza y solamente lo tiene el área de contabilidad; existe un organigrama que especifica las unidades que operan en la entidad, sin embargo, no es funcional ya que el área administrativa ejerce las labores en casi todos los puestos debido a que no hay personal para laborar en las distintas unidade

A study on the discrimination of human skeletons using X-ray fluorescence and chemometric tools in chemical anthropology

Forensic anthropological investigations are often restricted in their outcomes by the resources allocated to them, especially in terms of positively identifying the victims exhumed from commingled mass graves. Commingled mass graves can be defined as those graves that contain a number of disarticulated human remains from different individuals that have been mixed by either natural processes or human interventions. The research developed aimed to apply the technique of non-destructive XRF analysis to test whether there is substantial differentiation within the trace elemental composition and their ratios of individuals to separate them using chemometric analysis. The results of the different atomic spectroscopic analyses combined with the use of multivariate analysis on a set of 5 skeletons produced a series of plots using Principal Component Analysis that helped to separate them with a high percentage of accuracy when two, three or four skeletons needed to be separated. Also, two new elemental ratios, Zn/Fe related to metabolic activities and K/Fe related to blood flow into the bone, have been defined for their use in forensic anthropology for the first time to aid in the separation. © 2013 Elsevier Ireland Ltd