330 research outputs found
Truly On-The-Fly LTL Model Checking
We propose a novel algorithm for automata-based LTL model checking that
interleaves the construction of the generalized B\"{u}chi automaton for the
negation of the formula and the emptiness check. Our algorithm first converts
the LTL formula into a linear weak alternating automaton; configurations of the
alternating automaton correspond to the locations of a generalized B\"{u}chi
automaton, and a variant of Tarjan's algorithm is used to decide the existence
of an accepting run of the product of the transition system and the automaton.
Because we avoid an explicit construction of the B\"{u}chi automaton, our
approach can yield significant improvements in runtime and memory, for large
LTL formulas. The algorithm has been implemented within the SPIN model checker,
and we present experimental results for some benchmark examples
Car path tracking in traffic flow networks with bounded buffers at junctions
This article deals with the modeling for an individual car path through a road network, where the dynamics is driven by a coupled system of ordinary and partial differential equations. The network is characterized by bounded buffers at junctions that allow for the interpretation of roundabouts or on-ramps while the traffic dynamics is based on first-order macroscopic equations of Lighthill-Whitham-Richards (LWR) type. Trajectories for single drivers are then influenced by the surrounding traffic and can be tracked by appropriate numerical algorithms. The computational experiments show how the modeling framework can be used as navigation device
The food seeking behavior of slime mold: a macroscopic approach
Starting from a particle model we derive a macroscopic aggregation-diffusion
equation for the evolution of slime mold under the assumption of propagation of
chaos in the large particle limit. We analyze properties of the macroscopic
model in the stationary case and study the behavior of the slime mold between
food sources. The efficient numerical simulation of the aggregation-diffusion
equation allows for a detailed analysis of the interplay between the different
regimes drift, interaction and diffusion.Comment: 23 pages, 11 figure
Refinement of components in connection-safe assemblies with synchronous and asynchronous communication
Rising Food Insecurity and Conservative Policy in the US: Impact on the Elderly
Food insecurity, a critical problem in the developing world, has recently received increased attention among wealthy nations. Food insecurity, broadly defined, is when a lack of resources prevents household members from having enough food. In the US, food insecurity has been rising while social safety net programs to ameliorate hunger among at-risk households have been targeted for cuts by conservatives. Our main objective was to assess the prevalence and impact of food insecurity among the elderly. In a survey of 500 older, homebound meal clients in New York City, we found that nearly one in five (17%) is food insecure, 89% endure chronic health problems, 14% live with severe functional impairments, 38% are in declining health, and 10% experience unmet needs for services. New York City’s oldest community residents have serious health problems, multiple unmet social service needs, and often suffer from food insecurity. Understanding the relationship between these issues is critical if community organizations and government agencies at all levels—even in wealthy countries—are to be more effective in assuring the well being of their oldest residents
Diagnóstico para la construcción en adobe en infraestructuras de viviendas rurales del caserío Cau Cau del distrito de Namora, provincia de Cajamarca
RESUMEN
El presente informe se refirió a enfocar la investigación en la relación directa del
diagnóstico de los lineamientos arquitectónicos de las viviendas productivas rurales
construidas con tierra enfocada con la productividad y auto subsistencia del poblador
rural del caserío Cau Cau, distrito de Namora, particularmente se ha tomado el caso del
análisis de las viviendas productivas existentes en este caserío, teniendo en cuenta la
realidad que afrontan, las cuales no son infraestructuras adecuadas debido a que en
muchos casos, no han sido diseñadas sino adaptadas a las necesidades de su población
sin seguir pautas técnicas de arquitectura e ingeniería que garantice y satisfaga las
necesidades de su población, así como el análisis de casos y el estudio de proyectos del
mismo tipo en nuestro país.
Por lo tanto se planteó como propósito realizar el diagnóstico de los lineamientos
arquitectónicos (función, espacio, forma y estructura), presentes de la viviendas
productivas rurales del caserío Cau Cau, y el estudio de casos similares en nuestro país
para poder así establecer los principios básicos que se necesitan para el diseño y
propuesta de la vivienda productiva estableciendo la auto sostenibilidad del poblador rural
como un requisito indispensable en la propuesta y diseño de las infraestructuras
productivas de integración del conjunto.
Con este objeto se decide tomar en cuenta dos unidades de estudio para llegar a
la solución arquitectónica; en primera instancia la unidad de estudio que analiza el
diagnóstico y lineamientos de diseño presentes en las viviendas rurales del caserío Cau
Cau y la segunda que analiza los casos de viviendas productivas en Latinoamérica y en
nuestro país. Estas unidades de estudio son las que proporcionan los lineamientos arquitectónicos y estrategias que son traducidas a un lenguaje arquitectónico para su
aplicación en el proyecto.
Finalmente, desarrolladas las unidades de estudio y obteniendo un proyecto
arquitectónico se llegó a la conclusión de la hipótesis, la cual considera que los
lineamientos arquitectónicos si mejoran el diseño de las viviendas productivas rurales del
caserío Cau Cau del distrito de Namora en la Provincia de Cajamarca.ABSTRACT
This report referred to focus research on the direct relationship of the diagnosis of
the architectural guidelines of rural productive houses built with earth focused to
productivity and self-subsistence of the rural population of the village Cau Cau,
district Namora, particularly has been taken for the analysis of existing production
houses in this village, taking into account the reality they face, which are not
adequate infrastructures because in many cases, have not been designed but
adapted to the needs of its population without following technical guidelines
architectural and engineering that guarantees and meets the needs of its
population as well as the annals of cases and the study of similar projects in our
country.Thus arose intended to make the diagnosis of architectural guidelines
(function, space, form and structure) present in the rural production houses in the
village Cau Cau, and the study of similar cases in our country to well established
principles basic needed for the design and production of housing proposed
establishing self-sustainability of the rural population as a requirement in the
proposal and design of productive infrastructure assembly integration. For this
purpose it was decided to take into account two studio units to reach the
architectural solution; in the first instance the study unit that analyzes the
diagnosis and design guidelines present in rural households of the village Cau
Cau and the second analyzes cases of housing production in Latin America and
in our country. These study units are providing architectural guidelines and
strategies are translated into an architectural language for use in the project.
Finally, developed units of study and obtaining an architectural project concluded
the hypothesis, which considers the architectural design guidelines improve rural
Modeling random traffic accidents by conservation laws
We introduce a stochastic traffic flow model to describe random traffic accidents on a singleroad. The model is a piecewise deterministic process incorporating traffic accidents and is based on ascalar conservation law with space-dependent flux function. Using a Lax-Friedrichs discretization, weshow that the total variation is bounded in finite time and provide a theoretical framework to embedthe stochastic process. Additionally, a solution algorithm is introduced to also investigate the modelnumerically
Rising Food Insecurity and Conservative Policy in the US: Impact on the Elderly
Food insecurity, a critical problem in the developing world, has recently received increased attention among wealthy nations. Food insecurity, broadly defined, is when a lack of resources prevents household members from having enough food. In the US, food insecurity has been rising while social safety net programs to ameliorate hunger among at-risk households have been targeted for cuts by conservatives. Our main objective was to assess the prevalence and impact of food insecurity among the elderly. In a survey of 500 older, homebound meal clients in New York City, we found that nearly one in five (17%) is food insecure, 89% endure chronic health problems, 14% live with severe functional impairments, 38% are in declining health, and 10% experience unmet needs for services. New York City’s oldest community residents have serious health problems, multiple unmet social service needs, and often suffer from food insecurity. Understanding the relationship between these issues is critical if community organizations and government agencies at all levels—even in wealthy countries—are to be more effective in assuring the well being of their oldest residents
Scalable Designs for Quasiparticle-Poisoning-Protected Topological Quantum Computation with Majorana Zero Modes
We present designs for scalable quantum computers composed of qubits encoded
in aggregates of four or more Majorana zero modes, realized at the ends of
topological superconducting wire segments that are assembled into
superconducting islands with significant charging energy. Quantum information
can be manipulated according to a measurement-only protocol, which is
facilitated by tunable couplings between Majorana zero modes and nearby
semiconductor quantum dots. Our proposed architecture designs have the
following principal virtues: (1) the magnetic field can be aligned in the
direction of all of the topological superconducting wires since they are all
parallel; (2) topological -junctions are not used, obviating possible
difficulties in their fabrication and utilization; (3) quasiparticle poisoning
is abated by the charging energy; (4) Clifford operations are executed by a
relatively standard measurement: detection of corrections to quantum dot
energy, charge, or differential capacitance induced by quantum fluctuations;
(5) it is compatible with strategies for producing good approximate magic
states.Comment: 34 pages, 17 figures; v4: minor changes, final versio
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