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Modern hardware typically is characterized by a multitude of interacting physical components and software mechanisms. To address this complexity, security analysis should be modular: We would like to formulate and prove security properties of individual components, and then deduce the security of the overall design (encompassing hardware and software) from the security of the components. While this seems like an elusive goal, we argue that this is essentially the only feasible way to provide rigorous security analysis of modern hardware.This paper investigates the possibility of using the Universally Composable (UC) security framework towards this aim. The UC framework has been devised and successfully used in the theoretical cryptography community to study and formally prove security of arbitrarily interleaving cryptographic protocols. In particular, a sophisticated analytical toolbox has been developed using this framework. We provide an introduction to this frame-work, and investigate, via a number of examples, ways by which this framework can be used to facilitate a novel type of modular security analysis. This analysis applies to combined hardware and software systems, and investigates their security against attacks that combine both physical and digital steps.

Modern hardware typically is characterized by a multitude of interacting physical components and software mechanisms. To address this complexity, security analysis should be modular: We would like to formulate and prove security properties of individual components, and then deduce the security of the overall design (encompassing hardware and software) from the security of the components. While this seems like an elusive goal, we argue that this is essentially the only feasible way to provide rigorous security analysis of modern hardware.This paper investigates the possibility of using the Universally Composable (UC) security framework towards this aim. The UC framework has been devised and successfully used in the theoretical cryptography community to study and formally prove security of arbitrarily interleaving cryptographic protocols. In particular, a sophisticated analytical toolbox has been developed using this framework. We provide an introduction to this frame-work, and investigate, via a number of examples, ways by which this framework can be used to facilitate a novel type of modular security analysis. This analysis applies to combined hardware and software systems, and investigates their security against attacks that combine both physical and digital steps.

The index coding problem is studied from an interference alignment perspective providing new results as well as new insights into, and generalizations of, previously known results. An equivalence is established between the capacity of multiple unicast index coding (where each message is desired by exactly one receiver), and groupcast index coding (where a message can be desired by multiple receivers), which settles the heretofore open question of insufficiency of linear codes for the multiple unicast index coding problem by equivalence with groupcast settings, where this question has previously been answered. Necessary and sufficient conditions for the achievability of rate half per message in the index coding problem are shown to be a natural consequence of interference alignment constraints, and generalizations to feasibility of rate 1/(L+1)per message when each destination desires at least L messages, are similarly obtained. Finally, capacity optimal solutions are presented to a series of symmetric index coding problems inspired by the local connectivity and local interference characteristics of wireless networks. The solutions are based on vector linear coding. © 1963-2012 IEEE.

The index coding problem is studied from an interference alignment perspective providing new results as well as new insights into, and generalizations of, previously known results. An equivalence is established between the capacity of multiple unicast index coding (where each message is desired by exactly one receiver), and groupcast index coding (where a message can be desired by multiple receivers), which settles the heretofore open question of insufficiency of linear codes for the multiple unicast index coding problem by equivalence with groupcast settings, where this question has previously been answered. Necessary and sufficient conditions for the achievability of rate half per message in the index coding problem are shown to be a natural consequence of interference alignment constraints, and generalizations to feasibility of rate 1/(L+1)per message when each destination desires at least L messages, are similarly obtained. Finally, capacity optimal solutions are presented to a series of symmetric index coding problems inspired by the local connectivity and local interference characteristics of wireless networks. The solutions are based on vector linear coding. © 1963-2012 IEEE.

It is shown that a greedy orthogonal access scheme achieves the sum degrees of freedom (DoF) of all one-dimensional (all nodes placed along a straight line) convex cellular networks (where cells are convex regions) when no channel knowledge is available at the transmitters except the knowledge of the network topology. In general, optimality of orthogonal access holds neither for two-dimensional convex cellular networks nor for one-dimensional non-convex cellular networks, thus revealing a fundamental limitation that arises when both one-dimensional and convex properties are simultaneously enforced. The result also establishes the sum capacity of the corresponding class of index coding problems. © 2013 IEEE.

It is shown that a greedy orthogonal access scheme achieves the sum degrees of freedom (DoF) of all one-dimensional (all nodes placed along a straight line) convex cellular networks (where cells are convex regions) when no channel knowledge is available at the transmitters except the knowledge of the network topology. In general, optimality of orthogonal access holds neither for two-dimensional convex cellular networks nor for one-dimensional non-convex cellular networks, thus revealing a fundamental limitation that arises when both one-dimensional and convex properties are simultaneously enforced. The result also establishes the sum capacity of the corresponding class of index coding problems. © 2013 IEEE.

Two case studies are presented on the use of rock mechanics programs for improving the design of pillars and openings in trona mines. The first gives the results of tomographic surveys in narrow yield pillars, in conjunction with stress measurements. The study provides original data on post-peak load-carrying capacities of yield pillars and gives a basis for evaluating other mines. The second case involves detailed measurements of roof-bolt strain, roof deformation and gas pressure in a mine roof, in a panel where wide pillars are used. The measurements provide a better understanding of lateral forces imposed on roof bolts as a result of creep and of differences in material properties near trona-shale interfaces. Finite-difference models demonstrate the ground-control advantages of using properly shaped openings to reduce roof movements and support requirements while improving roof stability., Two case studies are presented on the use of rock mechanics programs for improving the design of pillars and openings in trona mines. The first gives the results of tomographic surveys in narrow yield pillars, in conjunction with stress measurements. The study provides original data on post-peak load-carrying capacities of yield pillars and gives a basis for evaluating other mines. The second case involves detailed measurements of roof-bolt strain, roof deformation and gas pressure in a mine roof, in a panel where wide pillars are used. The measurements provide a better understanding of lateral forces imposed on roof bolts as a result of creep and of differences in material properties near trona-shale interfaces. Finite-difference models demonstrate the ground-control advantages of using properly shaped openings to reduce roof movements and support requirements while improving roof stability.

The US Bureau of Mines has implemented a geophysical instrumentation programme in a southern Wyoming mine to study changes in roof stability during development mining. The case study was unique in providing integrated measurements of a mine roof, floor and pillar, and tracking failure growth around mining excavations. Lithology and roof conditions were mapped and cores were tested at the beginning and end of monitoring to assess structural damage. It was shown that failure initiated in the mine floor and spread to the pillar and roof. The field measurements were essential for understanding strata interaction and provided essential input for numerical models. In particular a model incorporating the strain-softening material behaviour for the floor showed best agreement between measured deformation patterns and the calculated results., The US Bureau of Mines has implemented a geophysical instrumentation programme in a southern Wyoming mine to study changes in roof stability during development mining. The case study was unique in providing integrated measurements of a mine roof, floor and pillar, and tracking failure growth around mining excavations. Lithology and roof conditions were mapped and cores were tested at the beginning and end of monitoring to assess structural damage. It was shown that failure initiated in the mine floor and spread to the pillar and roof. The field measurements were essential for understanding strata interaction and provided essential input for numerical models. In particular a model incorporating the strain-softening material behaviour for the floor showed best agreement between measured deformation patterns and the calculated results.

Long-term measurements from five underground mines are presented to demonstrate how such measurements can be applied. The case studies addressed both global aspects of strata response to mining activities and local ground behaviour and loading of support. Static measurements of stress and deformation were made as well as geophysical measurements. Pillar behaviour, roof-floor deformation patterns, overburden response and microseismic activity were quantified by the case studies while large-scale studies quantified the non-uniform nature of overburden deformation and collapse. Local measurements addressed yield and stable pillar load deformation characteristics as well as the performance of support systems under combined axial and lateral loads., Long-term measurements from five underground mines are presented to demonstrate how such measurements can be applied. The case studies addressed both global aspects of strata response to mining activities and local ground behaviour and loading of support. Static measurements of stress and deformation were made as well as geophysical measurements. Pillar behaviour, roof-floor deformation patterns, overburden response and microseismic activity were quantified by the case studies while large-scale studies quantified the non-uniform nature of overburden deformation and collapse. Local measurements addressed yield and stable pillar load deformation characteristics as well as the performance of support systems under combined axial and lateral loads.

The study, initiated by the US Bureau of Land Management, examined the economic feasibility of using unconventional - short or odd-shaped - longwalls for the recovery of small or medium-sized coal reserves according to geological and site-specific conditions. The work included analysis of the geological, geotechnical and economic factors that influence recovery of small reserves, analysis of historic changes in supply, demand and coal prices, development of typical cost models for room and pillar and for longwall mines, and evolution of a practical method for determining maximum economic recovery. The methodology included an evaluation of the ratio of coal mined during longwall mining to that mined for development, as well as an assessment of the increased cost of adding new sections for the exploitation of small reserves., The study, initiated by the US Bureau of Land Management, examined the economic feasibility of using unconventional - short or odd-shaped - longwalls for the recovery of small or medium-sized coal reserves according to geological and site-specific conditions. The work included analysis of the geological, geotechnical and economic factors that influence recovery of small reserves, analysis of historic changes in supply, demand and coal prices, development of typical cost models for room and pillar and for longwall mines, and evolution of a practical method for determining maximum economic recovery. The methodology included an evaluation of the ratio of coal mined during longwall mining to that mined for development, as well as an assessment of the increased cost of adding new sections for the exploitation of small reserves.

A geologic programme has been implemented to improve stability and support requirements along deep two-entry longwall gateroads at the Deer Creek coal mine operations in Utah, USA. In combination with geotechnical monitoring and mine seismicity reviews, it has become possible to improve longwall layout designs for two seam extraction of the Hiawatha and Blind Canyon seams. The geologic programme involves surface and in-mine exploration drilling and mapping, rock mechanics testing and measurements of changes in depositional and structural conditions during development of every longwall gateroad. The geotechnical program consists of underground measurements at seven locations in two neighbouring mining districts located in the coal seams under moderate to deep cover. Additional measurements, including data on seismicity and face conditions, have been incorporated into the data collection programme for verifying the in situ coal strength and load transfer mechanisms. Geologic mapping results are also used to predict the local stability of headgate and tailgate entries, combining mine roof mapping, stratigraphic profiles of the coal and roof and depth-of-cover information and dual-seam mine overlays for planning roof and rib support for the retreating longwall sections. Support pillars are used for long-term mains and sub-main, and yield pillars for longwall gateroads and bleeder entries. The irregularly shaped transitional pillars in neck-downs between support pillar and yield pillar sections must have appropriate safety factors while narrowing down from the support to the yield pillar size. Several methods for determining the safety factors are employed, including ARMPS and boundary element stress analyses. Site specific coal and roof conditions are analysed using rock mass ratings and the coal mine roof rating system., A geologic programme has been implemented to improve stability and support requirements along deep two-entry longwall gateroads at the Deer Creek coal mine operations in Utah, USA. In combination with geotechnical monitoring and mine seismicity reviews, it has become possible to improve longwall layout designs for two seam extraction of the Hiawatha and Blind Canyon seams. The geologic programme involves surface and in-mine exploration drilling and mapping, rock mechanics testing and measurements of changes in depositional and structural conditions during development of every longwall gateroad. The geotechnical program consists of underground measurements at seven locations in two neighbouring mining districts located in the coal seams under moderate to deep cover. Additional measurements, including data on seismicity and face conditions, have been incorporated into the data collection programme for verifying the in situ coal strength and load transfer mechanisms. Geologic mapping results are also used to predict the local stability of headgate and tailgate entries, combining mine roof mapping, stratigraphic profiles of the coal and roof and depth-of-cover information and dual-seam mine overlays for planning roof and rib support for the retreating longwall sections. Support pillars are used for long-term mains and sub-main, and yield pillars for longwall gateroads and bleeder entries. The irregularly shaped transitional pillars in neck-downs between support pillar and yield pillar sections must have appropriate safety factors while narrowing down from the support to the yield pillar size. Several methods for determining the safety factors are employed, including ARMPS and boundary element stress analyses. Site specific coal and roof conditions are analysed using rock mass ratings and the coal mine roof rating system.

A new criterion was proposed for test mining and design of yield pillars. It was shown that pillar failure (yielding) can be stable depending on peak pillar strength and post-failure stress-strain slope. Pillar or residual strength should be chosen below critical stress levels, causing stress-induced stability problems. Post-failure stress-strain should be gradual to avoid excessive roof deformation. A two-entry gate system is inherently more stable than a three-entry system because it minimises weak roof and rib exposure and eliminates four-way intersections., A new criterion was proposed for test mining and design of yield pillars. It was shown that pillar failure (yielding) can be stable depending on peak pillar strength and post-failure stress-strain slope. Pillar or residual strength should be chosen below critical stress levels, causing stress-induced stability problems. Post-failure stress-strain should be gradual to avoid excessive roof deformation. A two-entry gate system is inherently more stable than a three-entry system because it minimises weak roof and rib exposure and eliminates four-way intersections.