Método de cálculo de parâmetros racionais para dispositivos com eixo de rotação horizontal para disseminar fertilizantes minerais e sementes

The article proposes the modeling technique for the uniform distribution of particles by a throwing unit. The material is devoted to the substantiation of rational parameters and operating modes of vertical throwing units to distribute the particles of fertilizers and seeds.El artículo propone la técnica de modelado para la distribución uniforme de partículas por una unidad de lanzamiento. El material está dedicado a la fundamentación de parámetros racionales y modos de operación de unidades de lanzamiento vertical para distribuir las partículas de fertilizantes y semillas. O artigo propõe a técnica de modelagem para a distribuição uniforme de partículas por uma unidade de arremesso. O material é dedicado à comprovação de parâmetros racionais e modos de operação de unidades de arremesso vertical para distribuir as partículas de fertilizantes e sementes

Rational bidding using reinforcement learning: an application in automated resource allocation

The application of autonomous agents by the provisioning and usage of computational resources is an attractive research field. Various methods and technologies in the area of artificial intelligence, statistics and economics are playing together to achieve i) autonomic resource provisioning and usage of computational resources, to invent ii) competitive bidding strategies for widely used market mechanisms and to iii) incentivize consumers and providers to use such market-based systems. The contributions of the paper are threefold. First, we present a framework for supporting consumers and providers in technical and economic preference elicitation and the generation of bids. Secondly, we introduce a consumer-side reinforcement learning bidding strategy which enables rational behavior by the generation and selection of bids. Thirdly, we evaluate and compare this bidding strategy against a truth-telling bidding strategy for two kinds of market mechanisms – one centralized and one decentralized

Q-Strategy: A Bidding Strategy for Market-Based Allocation of Grid Services

The application of autonomous agents by the provisioning and usage of computational services is an attractive research field. Various methods and technologies in the area of artificial intelligence, statistics and economics are playing together to achieve i) autonomic service provisioning and usage of Grid services, to invent ii) competitive bidding strategies for widely used market mechanisms and to iii) incentivize consumers and providers to use such market-based systems. The contributions of the paper are threefold. First, we present a bidding agent framework for implementing artificial bidding agents, supporting consumers and providers in technical and economic preference elicitation as well as automated bid generation by the requesting and provisioning of Grid services. Secondly, we introduce a novel consumer-side bidding strategy, which enables a goal-oriented and strategic behavior by the generation and submission of consumer service requests and selection of provider offers. Thirdly, we evaluate and compare the Q-strategy, implemented within the presented framework, against the Truth-Telling bidding strategy in three mechanisms – a centralized CDA, a decentralized on-line machine scheduling and a FIFO-scheduling mechanisms

Optogalvanic Spectroscopy of Metastable States in Yb^{+}

The metastable ^{2}F_{7/2} and ^{2}D_{3/2} states of Yb^{+} are of interest for applications in metrology and quantum information and also act as dark states in laser cooling. These metastable states are commonly repumped to the ground state via the 638.6 nm ^{2}F_{7/2} -- ^{1}D[5/2]_{5/2} and 935.2 nm ^{2}D_{3/2} -- ^{3}D[3/2]_{1/2} transitions. We have performed optogalvanic spectroscopy of these transitions in Yb^{+} ions generated in a discharge. We measure the pressure broadening coefficient for the 638.6 nm transition to be 70 \pm 10 MHz mbar^{-1}. We place an upper bound of 375 MHz/nucleon on the 638.6 nm isotope splitting and show that our observations are consistent with theory for the hyperfine splitting. Our measurements of the 935.2 nm transition extend those made by Sugiyama et al, showing well-resolved isotope and hyperfine splitting. We obtain high signal to noise, sufficient for laser stabilisation applications.Comment: 8 pages, 5 figure

A Single Laser System for Ground-State Cooling of 25-Mg+

We present a single solid-state laser system to cool, coherently manipulate and detect $^{25}$Mg$^+$ ions. Coherent manipulation is accomplished by coupling two hyperfine ground state levels using a pair of far-detuned Raman laser beams. Resonant light for Doppler cooling and detection is derived from the same laser source by means of an electro-optic modulator, generating a sideband which is resonant with the atomic transition. We demonstrate ground-state cooling of one of the vibrational modes of the ion in the trap using resolved-sideband cooling. The cooling performance is studied and discussed by observing the temporal evolution of Raman-stimulated sideband transitions. The setup is a major simplification over existing state-of-the-art systems, typically involving up to three separate laser sources

Tunable Mid-Infrared Laser Sources for Trace-Gas Analysis

We demonstrate advanced experimental approaches to photoacoustic gas detection with tunable mid-infrared (mid-IR) laser sources of different types. A gas analyzer for registration of various gas components based on a tunable narrow-linewidth optical parametric oscillator (OPO) was designed and investigated. Using this OPO, the possibility of measuring the trace concentration (~2÷3 ppm) of methane (CH4) in air was experimentally shown. The gas detection capability was enhanced by introducing injection seeding into the OPO. Another gas analyzer was based on a quantum cascade laser (tunable within the range ~7.6 ÷7.7 μm) and a resonant differential photoacoustic detector. Detection of the ultra-low concentration (~0.3 ppm) of methane in air was achieved (the standard dispersion was (1σ) ≈ (10–11) ppb with an integration time of 10 s). We compare the presented approaches and outline their further development. © 2021 Institute of Physics Publishing. All rights reserved.This work was partially supported by the Ministry of Science and Higher Education of the Russian Federation (grant FSUS-2020-0036). The Fan-out MgO: PPLN chip was prepared by A.A. and V.S with support from Russian Foundation for Basic Research (grant RFBR-mk-18-29-20077). The CH4 spectroscopic experiments were funded by RFBR, project number 19-32-60055

Non-locality and Communication Complexity

Quantum information processing is the emerging field that defines and realizes computing devices that make use of quantum mechanical principles, like the superposition principle, entanglement, and interference. In this review we study the information counterpart of computing. The abstract form of the distributed computing setting is called communication complexity. It studies the amount of information, in terms of bits or in our case qubits, that two spatially separated computing devices need to exchange in order to perform some computational task. Surprisingly, quantum mechanics can be used to obtain dramatic advantages for such tasks. We review the area of quantum communication complexity, and show how it connects the foundational physics questions regarding non-locality with those of communication complexity studied in theoretical computer science. The first examples exhibiting the advantage of the use of qubits in distributed information-processing tasks were based on non-locality tests. However, by now the field has produced strong and interesting quantum protocols and algorithms of its own that demonstrate that entanglement, although it cannot be used to replace communication, can be used to reduce the communication exponentially. In turn, these new advances yield a new outlook on the foundations of physics, and could even yield new proposals for experiments that test the foundations of physics.Comment: Survey paper, 63 pages LaTeX. A reformatted version will appear in Reviews of Modern Physic

Ramsey-Bordé interferometer and embedded Ramsey interferometer with molecular matter waves of

A matter wave interferometer based on a molecular beam of K2 has been designed for observation of both exits: with molecules in the electronically excited state and in the ground state. In addition to the excited state fluorescence the molecular ground state population is detected with a further laser. Two transitions to different electronic states were employed for this purpose and their usefulness is compared. Under the present experimental conditions both interferometer exits show a superposition of different interference patterns due to the influence of transverse and longitudinal overlaps of the interfering matter waves. The interference patterns have been analyzed to be composed of a contribution caused by a two beam splitter Ramsey interference and Ramsey-Bordé pattern with four beam splitters. This overlap of interference signals influences the suitability of the matter wave interferometer for phase measurements of the interferences

Frequency measurements in the b

Absolute transition frequencies of the b 3Π(0u+) - X 1Σg+ system of K2 were measured in a molecular beam with Lamb dip absorption spectroscopy applying a frequency comb from a femtosecond pulsed laser. Both, K atoms and K2 molecules are present in the beam and are expected to interact by collisions. The atoms can be deflected optically out of the beam, and thus the collision rate between K atoms and K2 molecules is changed by about an order of magnitude. The molecular transition frequencies for low collisional rate are compared with those for high one. Limits for the collisional frequency shift within the beam are determined