797 research outputs found

    Long-term operation of a multi-channel cosmic muon system based on scintillation counters with MRS APD light readout

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    A Cosmic Ray Test Facility (CRTF) is the first large-scale implementation of a scintillation triggering system based on a new scintillation technique known as START. In START, the scintillation light is collected and transported by WLS optical fibers, while light detection is performed by pairs of avalanche photodiodes with the Metal-Resistor-Semiconductor structure operated in the Geiger mode (MRS APD). START delivers 100% efficiency of cosmic muon detection, while its intrinsic noise level is less than 10^{-2} Hz. CRTF, consisting of 160 START channels, has been continuously operated by the ALICE TOF collaboration for more than 25 000 hours, and has demonstrated a high level of stability. Fewer than 10% of MRS APDs had to be replaced during this period.Comment: Proceedings of NDIP-2008. 8 pages, 8 figures, 6 reference

    Photothermal deflection determination of iron(II) with ferrozine with sorption preconcentration on silufol plates

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    Photothermal deflection spectroscopy was applied to the selective detection of iron(II) chelate with ferrozine by its sorption preconcentration on Silufol plates. The linearity range was 1 × 10-11-6 × 10 -8 mol cm-2 of chelate at the plate surface, which corresponded to 1 × 10-9 × 10-6 M of chelate in solution. The limits of detection and quantification are 8 × 10 -12 and 2.5 × 10-11 mol cm-2 at the plate from 15 μL of test solution (0.5 nM and 1.5 nM in solution, respectively), and the absolute detection limit is 8 fmol in the whole spot applied to a plate. Characteristics and features of photothermal deflection detection are discussed. © 2008 Society for Applied Spectroscopy

    Strategic approach to assessing economic sustainability objects of mineral resources sector of Russia

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    The article gives a new definition of economic systems (ES) stability with its distinct strategic content. The main approaches to assessment of sustainability, based on the use of strategic cards, including Balanced Scorecard (BSC), are considered. Synchronous management of effectiveness, risks and chances of the ES exhausts the agenda of managing economic sustainability of ES when it operates in the face of a wide range of challenges. BSC in mineral resources sector (MRS) can be built during the aggregation of BSC by industry and individual enterprises. The use of 4 ´ 6 matrix formalism is proposed as the main tool for modeling economic sustainability of the ES

    START as the detector of choice for large-scale muon triggering systems

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    Further progress in building high-granular large-scale systems based on Scintillation Tiles with MRS APD light readout (START) became possible thanks to the creation of an improved version of MRS APD. The cost of the system may now be significantly reduced by using inexpensive extruded scintillator. More than 160 START samples were assembled based on this design modification and proved to possess 100% MIP detection efficiency and the intrinsic noise rate of less than 0.08 Hz. Long-term stability of START characteristics was confirmed after 3.5 months of operation

    STRATEGIC MANAGEMENT OF THE ECONOMIC SUSTAINABILITY OF A COMPANY IN THE PARADIGM OF FUZZY LOGIC

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    The theory of economic resilience is actively developing in Russian and foreign scientific studies. Most of them lack a comprehensive approach to the issue of resilience, the ability to assess the behaviour of economic systems under conditions of uncertainty and to offer optimal solutions to ensure the resilience of economic systems (enterprises, industries) in difficult conditions. It is necessary to develop optimal algorithms for managing economic systems under adverse effects (AE) of a natural, technological, or military nature. The article describes the method of managing economic resilience in three-dimensional spaces: ‘stability – efficiency’, ‘risk – efficiency’, and ‘chance – efficiency’. The results of three approaches to resilience management are compared.It can be tentatively assumed that the stability of an individual company is ensured if the economic stability index RI exceeds the level of 0.6 and the return on equity is at least 20% per annum. More generally, in the ‘resilience – efficiency’ space, the domain of stable states of the enterprise is described by a fuzzy parabolic R lens. In the ‘risk – efficiency’ and ‘chance – efficiency’ domains, the space of optimal solutions is represented by a set of non-dominated Pareto alternatives, united by a fuzzy parabolic efficient bound of the solution portfolio set. The organisation can control its level of economic resilience within multiple representations and act according to a predetermined plan in the event of a temporary loss of resilience. The research is original, using the methods of fuzzy set theory and soft computing. A technology has been proposed to ensure the economic resilience of systems operating in difficult conditions (e.g. in new regions of the Russian Federation where large-scale military actions are taking place). This makes the study highly relevant and practical

    模糊逻辑范式内企业经济可持续性的战略管理

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    The theory of economic resilience is actively developing in Russian and foreign scientific studies. Most of them lack a comprehensive approach to the issue of resilience, the ability to assess the behaviour of economic systems under conditions of uncertainty and to offer optimal solutions to ensure the resilience of economic systems (enterprises, industries) in difficult conditions. It is necessary to develop optimal algorithms for managing economic systems under adverse effects (AE) of a natural, technological, or military nature. The article describes the method of managing economic resilience in three-dimensional spaces: ‘stability – efficiency’, ‘risk – efficiency’, and ‘chance – efficiency’. The results of three approaches to resilience management are compared.It can be tentatively assumed that the stability of an individual company is ensured if the economic stability index RI exceeds the level of 0.6 and the return on equity is at least 20% per annum. More generally, in the ‘resilience – efficiency’ space, the domain of stable states of the enterprise is described by a fuzzy parabolic R lens. In the ‘risk – efficiency’ and ‘chance – efficiency’ domains, the space of optimal solutions is represented by a set of non-dominated Pareto alternatives, united by a fuzzy parabolic efficient bound of the solution portfolio set. The organisation can control its level of economic resilience within multiple representations and act according to a predetermined plan in the event of a temporary loss of resilience. The research is original, using the methods of fuzzy set theory and soft computing. A technology has been proposed to ensure the economic resilience of systems operating in difficult conditions (e.g. in new regions of the Russian Federation where large-scale military actions are taking place). This makes the study highly relevant and practical.Теория экономической устойчивости активно развивается в российских и зарубежных научных исследованиях, однако большинству этих исследований недостает комплексности подхода к проблематике устойчивости, способности оценивать поведение экономических систем в условиях неопределенности, а также предлагать оптимальные решения по обеспечению устойчивости экономических систем (предприятий, отраслей) в сложных условиях. Необходимо выработать оптимальные алгоритмы управления устойчивостью экономических систем в условиях неблагоприятных внешних воздействий на них природного, техногенного или военного характера. В работе описывается порядок управления экономической устойчивостью в трех координатных пространствах: «устойчивость – эффективность», «риск – эффективность» и «шанс – эффективность». Сравниваются результаты трех обозначенных подходов к управлению устойчивостью.Можно предварительно считать, что устойчивость отдельной компании обеспечена, если индекс экономической устойчивости RI превышает уровень 0,6, а отдача на собственный капитал составляет не ниже 20% годовых. С более общих позиций в пространстве «устойчивость – эффективность» область устойчивых состояний предприятия описывается нечетко-параболической R-линзой.В пространствах «риск – эффективность» и «шанс – эффективность» область оптимальных решений представляет собой множество недоминируемых в смысле Парето альтернатив, объединенных нечетко-параболической эффективной границей портфельного множества решений. Предприятие может контролировать уровень своей экономической устойчивости в рамках нескольких представлений и действовать по заранее известному плану в случае временной потери устойчивости.Настоящее исследование является оригинальным, в нем применяются методы теории нечетких множеств и мягких вычислений. Предложена технология обеспечения экономической устойчивости для систем, находящихся в осложненных условиях функционирования (например, в новых регионах РФ, где ведутся полномасштабные военные действия). Это обуславливает чрезвычайную актуальность и практическую значимость проведенного исследования.俄罗斯和外国的科学研究都在积极发展经济可持续性理论。然而,这些研究大多缺乏处理可持续性问题的综合方法、在不确定条件下评估经济系统行为的能力以及提供最佳解决方案,确保经济系统(企业、行业)在复杂条件下的可持续发展。有必要开发最佳算法,以便在自然、人为或军事性质的不利外部影响下管理经济系统的可持续性。本文章描述了三个坐标空间中经济可持续性管理的顺序:“可持续性——效率”、“风险——效率”和“机会——效率”。而且对已确定的三种可持续性管理方法的结果进行比较。可以初步认为,如果经济可持续发展 RI 指数超过 0.6,且股本回报率每年至少达到 20%,则单个企业的可持续发展能力就得到了保证。从更广泛的角度看,在“可持续性——效率”空间中,企业的稳定状态区域可以用模糊抛物线 R 镜头来描述。在“风险——效率”和“机会——效率”空间中,最优解的领域是在帕累托效率意义上非优势的备选方案集合,它们由投资组合解集的模糊抛物线有效边界联合起来。企业可从以下几个方面监测其经济可持续性水平并在暂时失去稳定的情况下按照已知计划行事。本研究具有独创性,应用了模糊集理论和软计算方法。作者提出了以确保复杂工作条件下系统的经济可持续性技术(例如,在俄罗斯联邦正在开展全面军事行动的新地区)。这决定了所开展研究的极端相关性和实际意义

    Phonon-assisted radiofrequency absorption by gold nanoparticles resulting in hyperthermia

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    It is suggested that in gold nanoparticles (GNPs) of about 5 nm sizes used in the radiofrequency (RF) hyperthermia, an absorption of the RF photon by the Fermi electron occurs with involvement of the longitudinal acoustic vibrational mode (LAVM), the dominating one in the distribution of vibrational density of states (VDOS). This physical mechanism helps to explain two observed phenomena: the size dependence of the heating rate (HR) in GNPs and reduced heat production in aggregated GNPs. The argumentation proceeds within the one-electron approximation, taking into account the discretenesses of energies and momenta of both electrons and LAVMs. The heating of GNPs is thought to consist of two consecutive processes: first, the Fermi electron absorbs simultaneously the RF photon and the LAVM available in the GNP; hereafter the excited electron gets relaxed within the GNP's boundary, exciting a LAVM with the energy higher than that of the previously absorbed LAVM. GNPs containing the Ta and/or Fe impurities are proposed for the RF hyperthermia as promising heaters with enhanced HRs, and GNPs with rare-earth impurity atoms are also brought into consideration. It is shown why the maximum HR values should be expected in GNPs with about 5-7 nm size.Comment: proceedings at the NATO Advanced Research workshop FANEM-2015 (Minsk, May 25-27, 2015). To be published in the final form in: "Fundamental and Applied NanoElectroMagnetics" (Springer Science + Business Media B.V.
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