70 research outputs found
Efficient Algorithms for Optimal Control of Quantum Dynamics: The "Krotov'' Method unencumbered
Efficient algorithms for the discovery of optimal control designs for
coherent control of quantum processes are of fundamental importance. One
important class of algorithms are sequential update algorithms generally
attributed to Krotov. Although widely and often successfully used, the
associated theory is often involved and leaves many crucial questions
unanswered, from the monotonicity and convergence of the algorithm to
discretization effects, leading to the introduction of ad-hoc penalty terms and
suboptimal update schemes detrimental to the performance of the algorithm. We
present a general framework for sequential update algorithms including specific
prescriptions for efficient update rules with inexpensive dynamic search length
control, taking into account discretization effects and eliminating the need
for ad-hoc penalty terms. The latter, while necessary to regularize the problem
in the limit of infinite time resolution, i.e., the continuum limit, are shown
to be undesirable and unnecessary in the practically relevant case of finite
time resolution. Numerical examples show that the ideas underlying many of
these results extend even beyond what can be rigorously proved.Comment: 19 pages, many figure
Integration of Ca-Looping Systems for CO2Capture in Cement Plants
Ca-Looping (CaL) has been demonstrated as a promising technology for CO2capture in coal-fired power plants. A promising application is also in cement plants, where the CaO-rich material purged from the CaL process can replace part or all of the raw material used for clinker production. The aim of this work is to investigate two process integration options of the CaL system based on fluidized bed and entrained flow reactors in a clinker burning process. The main advantages, constrains and research questions of the two configurations are discussed, and the mass and energy balances of the whole processes are detailed and analyzed
Chemical vapour deposition synthetic diamond: materials, technology and applications
Substantial developments have been achieved in the synthesis of chemical
vapour deposition (CVD) diamond in recent years, providing engineers and
designers with access to a large range of new diamond materials. CVD diamond
has a number of outstanding material properties that can enable exceptional
performance in applications as diverse as medical diagnostics, water treatment,
radiation detection, high power electronics, consumer audio, magnetometry and
novel lasers. Often the material is synthesized in planar form, however
non-planar geometries are also possible and enable a number of key
applications. This article reviews the material properties and characteristics
of single crystal and polycrystalline CVD diamond, and how these can be
utilized, focusing particularly on optics, electronics and electrochemistry. It
also summarizes how CVD diamond can be tailored for specific applications,
based on the ability to synthesize a consistent and engineered high performance
product.Comment: 51 pages, 16 figure
Artificial neural network for ecological-economic zoning as a tool for spatial planning
O objetivo deste trabalho foi analisar informaçÔes socioambientais por meio de rede neural artificial-mapa auto-organizĂĄvel (RNA-SOM), para fornecer subsĂdio ao zoneamento ecolĂłgico econĂŽmico (ZEE) como instrumento para diminuir a subjetividade do processo. A ĂĄrea de estudo compreende 16 municĂpios do Nordeste Paraense, expressivos no desenvolvimento agropecuĂĄrio do estado. O tratamento dos dados envolveu trĂȘs etapas: preparação dos dados em ambiente de sistema de informação geogrĂĄfica (SIG); processamento matemĂĄtico (RNA-SOM) dos dados; e visualização e interpretação dos resultados dos processamentos, o que permitiu o ordenamento territorial do Nordeste Paraense. Os resultados compreenderam 13 classes, reagrupadas de acordo com critĂ©rios de similaridade de comportamento em quatro categorias, que representam os principais eixos de sustentabilidade propostos para o Estado do ParĂĄ, a partir do ZEE existente. A metodologia proposta permite individualizar zonas na regiĂŁo que o ZEE nĂŁo havia definido, principalmente em razĂŁo da maior possibilidade de conjugar e integrar um grande nĂșmero de variĂĄveis fĂsicas, sociais e econĂŽmicas por meio do SOM.The objective of this work was to analyze social and environmental information through an artificial neural network-self-organizing map (ANN-SOM), in order to provide subsidy to ecologicaleconomic zoning (EEZ) as a tool to reduce the subjectivity of the process. The study area comprises 16 municipalities in the northeast of the state of ParĂĄ, Brazil, representative of the agricultural development in the state. Data processing involved three steps: preparation of the data in a geographic information system (GIS) environment; mathematical processing (ANN-SOM) of the data; and visualization and interpretation of the processing results, allowing the spatial planning of northeastern ParĂĄ. The results comprised 13 classes, regrouped according to behavioral similarity criteria into four categories, which represent the main areas of sustainability proposed for the state of ParĂĄ, according to existing EEZ. The proposed methodology allows individualizing areas in the region that EEZ had not defined, mainly due to the greater possibility of combining and integrating a large number of physical, social, and economic variables through the SOM
SpuÂcken mit TötÂungsÂvorÂsatz
Töten war selten einfacher als heutzutage. Eine etwas feuchte Aussprache, Husten und Spucken, all das kann tödlich sein. Cornelia Spörl erklĂ€rt, wann bedingter Tötungsvorsatz vorliegt â und eine Infizierung Mord oder Totschlag bedeutet
The Joint TerraSAR-X / TanDEM-X Mission Planning System
This paper recalls the essential system requirements and
elements for the joint TerraSAR-X / TanDEM-X mission
planning system. Its commissioning approach, tests and
results are described in detail
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