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排序方式: 共有830条查询结果,搜索用时 31 毫秒
61.
Back Cover: [3H]UR‐DE257: Development of a Tritium‐Labeled Squaramide‐Type Selective Histamine H2 Receptor Antagonist (ChemMedChem 1/2015)
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62.
Armin Tajalli Mohammad Chahardori Abbas Khodaverdi 《Analog Integrated Circuits and Signal Processing》2010,62(2):131-140
This article explores the main tradeoffs in design of power and area efficient bandgap voltage reference (BGR) circuits. A structural design methodology for optimizing the silicon area and power dissipation of CMOS BGRs will be introduced. For this purpose, basic equations of the bandgap circuit have been adapted such that can simply be applied in the optimization process. To improve the reliability of the designed circuit, the effect of amplifier offset has been also included in the optimization process. It is also shown that the minimum achievable power consumption and area are highly depending on the fabrication process parameters especially sheet resistivity of the available resistors in the technology and also the area of bipolar transistors. The proposed technique does not depend on a special process and can be applied for designing bandgap reference circuits with different topologies. 相似文献
63.
Davood Shishebori Iman Dayarian Armin Jabbarzadeh Farnaz Barzinpour 《The International Journal of Advanced Manufacturing Technology》2014,71(1-4):127-139
Locating certain facilities in predetermined sites is named the multiple facility location problems (MFLP). The objective of these kinds of problems is locating facilities to serve a given set of customers so that candidate sites and requirements are known. When the new facility sites have to be selected from a given set of candidate sites, the mentioned location problem becomes a discrete multiple facility location problem (DMFLP). In this paper, a special approach of DMFLP is considered where different multiple facilities have to be placed (location decision) and also customers have to be assigned to these facilities (allocation or assignment). The mathematical model of the proposed problem is developed, and with respect to the complexity of solving the mathematical model, especially in large scale, a new hybrid approach is proposed based on tabu search algorithm to solve the problem at each scale. Computational results on several randomly generated problems in comparison with a new proposed lower bound obtained from Lagrangian relaxation indicate that the proposed hybrid approach is both accurate and efficient. 相似文献
64.
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In many industries mixed-model assembly systems are increasingly supplied out of third-party consignment stock. This novel
trend gives rise to a new short-term sequencing problem which decides on the succession of models launched down the line and
aims at minimizing the cost of in-process inventory held by the manufacturer. In this work, we investigate the mathematical
structure of this part oriented mixed-model sequencing problem and prove that general instances of the problem are NP-hard
in the strong sense. Moreover, we develop a new Beam Search heuristic, which clearly outperforms existing solution procedures. 相似文献
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68.
Armin Herb 《Datenschutz und Datensicherheit - DuD》2011,35(4):270-274
Die Finanzierung des dualen Rundfunksystems in Deutschland und damit insbesondere der ?ffentlich-rechtlichen Rundfunkanstalten
soll ab dem 1. Januar 2013 auf eine neue Basis gestellt werden. Anstatt den bisherigen Gebühren für ein H?rfunk- oder Fernsehger?t
ist dann ein Rundfunkbeitrag für jede Wohnung und Betriebsst?tte zu leisten. Die nachfolgenden Ausführungen befassen sich
mit den datenschutzrechtlichen Vorschriften im neuen Rundfunkbeitragsstaatsvertrag der L?nder. 相似文献
69.
We present a mean-field approach for calculating thermodynamic properties(free energies) of protein–solvent systems. We apply this method to thetumor suppressor protein p53, where we study the stability of itstetramerization domain when subjected to site-directed mutagenesis. Acomparison with experimental results is included. 相似文献
70.
Analytic models based on discrete-time Markov chains (DTMC) are proposed to assess the algorithmic performance of Software Transactional Memory (TM) systems. Base STM variants are compared: optimistic STM with inplace memory updates and write buffering and pessimistic STM. Starting from an absorbing DTMC, closed-form analytic expressions are developed, which are quickly solved iteratively to determine key parameters of the considered STM systems, like the mean number of transaction restarts and the mean transaction length. Since the models reflect complex transactional behavior in terms of read/write locking, data consistency checks and conflict management independent of implementation details, they highlight the algorithmic performance advantages of one system over the other, which – due to their at times small differences – are often blurred by implementation of STM systems and even difficult to discern with statistically significant discrete-event simulations. 相似文献