950 resultados para -Compact categories


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General Relativity predicts the existence of gravitational waves, which carry information about the physical and dynamical properties of their source. One of the many promising sources of gravitational waves observable by ground-based instruments, such as in LIGO and Virgo, is the coalescence of two compact objects (neutron star or black hole). Black holes and neutron stars sometimes form binaries with short orbital periods, radiating so strongly in gravitational waves that they coalesce on astrophysically short timescales. General Relativity gives precise predictions for the form of the signal emitted by these systems. The most recent searches for theses events used waveform models that neglected the effects of black hole and neutron star spin. However, real astrophysical compact objects, especially black holes, are expected to have large spins. We demonstrate here a data analysis infrastructure which achieves an improved sensitivity to spinning compact binaries by the inclusion of spin effects in the template waveforms. This infrastructure is designed for scalable, low-latency data analysis, ideal for rapid electromagnetic followup of gravitational wave events.

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<p>This thesis is divided into three chapters. In the first chapter we study the smooth sets with respect to a Borel equivalence realtion E on a Polish space X. The collection of smooth sets forms -ideal. We think of smooth sets as analogs of countable sets and we show that an analog of the perfect set theorem for <sup>1</sup><sub>1</sub> sets holds in the context of smooth sets. We also show that the collection of <sup>1</sup><sub>1</sub> smooth sets is <sup>1</sup><sub>1</sub> on the codes. The analogs of thin sets are called sparse sets. We prove that there is a largest <sup>1</sup><sub>1</sub> sparse set and we give a characterization of it. We show that in L there is a <sup>1</sup><sub>1</sub> sparse set which is not smooth. These results are analogs of the results known for the ideal of countable sets, but it remains open to determine if large cardinal axioms imply that <sup>1</sup><sub>1</sub> sparse sets are smooth. Some more specific results are proved for the case of a countable Borel equivalence relation. We also study I(E), the -ideal of closed E-smooth sets. Among other things we prove that E is smooth iff I(E) is Borel.</p> <p>In chapter 2 we study -ideals of compact sets. We are interested in the relationship between some descriptive set theoretic properties like thinness, strong calibration and the covering property. We also study products of -ideals from the same point of view. In chapter 3 we show that if a -ideal I has the covering property (which is an abstract version of the perfect set theorem for <sup>1</sup><sub>1</sub> sets), then there is a largest <sup>1</sup><sub>1</sub> set in I<sup>int</sup> (i.e., every closed subset of it is in I). For -ideals on 2<sup></sup> we present a characterization of this set in a similar way as for C<sub>1</sub>, the largest thin <sup>1</sup><sub>1</sub> set. As a corollary we get that if there are only countable many reals in L, then the covering property holds for <sup>1</sup><sub>2</sub> sets.</p>

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A compact two-step modified-signed-digit arithmetic-logic array processor is proposed. When the reference digits are programmed, both addition and subtraction can be performed by the same binary logic operations regardless of the sign of the input digits. The optical implementation and experimental demonstration with an electron-trapping device are shown. Each digit is encoded by a single pixel, and no polarization is included. Any combinational logic can be easily performed without optoelectronic and electro-optic conversions of the intermediate results. The system is compact, general purpose, simple to align, and has a high signal-to-noise ratio. (C) 1999 Optical Society of America.

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The optical constants of two cyanine dye films that we prepared were measured with a RAP-1-type (RAP is rotating analyzer and polarizer) spectroscopic ellipsometer. Toward making a simplified model for the wafers of a recordable compact disk (CD-R), we give their optimization designs developed with the cyanine dye films. in addition, the dynamic storage performances of two sample disks were tested by our dynamic storage testing system. Measurement results of the sample disks were obtained to test and verify our film designs. (C) 2000 Optical Society of America. OCIS codes: 160.4890, 160.4760, 210.4810.

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A compact continuous-wave blue laser has been demonstrated by direct frequency doubling of a laser diode with a periodically poled lithium niobate (PPLN) waveguide crystal. The optimum PPLN temperature is near 28 degreesC, and the dependence of waveguide crystals on crystal temperature is less sensitive than that of bulk crystals. A total of 14.8 mW of 488-nm laser power has been achieved. (C) 2005 Optical Society of America.

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A diode pumped injection seeded single-longitudinal-mode (SLM) Nd:YAG laser is achieved by using the resonance-detection technique in Q-switching operation. The pulsed oscillator laser uses a folded cavity to achieve compact construction. This system operates at 100 Hz and provides over 20 mJ/pulse of single-frequency 1064 nm output. The M-2 values of horizontal and vertical axes are 1.58 and 1.41, respectively. The probability of putting out single-longitudinal-mode pulses is 100%. The 355 nm laser output produced by frequency tripling has a linewidth less than 200 MHz. The laser can run over eight hours continually without mode hopping.

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[EU]Gradu Amaierako lan honetan, enpresen gizarte erantzukizunak azkenaldian hartu duen garrantzia kontuan hartuta, kontzeptu hau jorratuko da eta eremu honetan burututako ekimen ezberdinen artean bat aukeratuko da, honen garapena eta inplementazioa aztertzeko. Hain zuzen ere, lan honetan erabiliko den ekimena, Munduko Hitzarmena edo Global Compact-a izango da. Hau, nazioarte mailako ekimen bat izanik, 10 printzipio proposatzen ditu, lau eremu ezberdinetan banatuz: Giza eskubideak, lan-arauak, ingurumena eta ustelkeriaren kontrako borroka. Bukatzeko, Global Compact-a aplikatzen duten sektore ezberdinetako hiru enpresa aukeratuko dira eta bakoitza dimentsio bat aztertzeko erabilia izango da, soziala, ekonomikoa eta ingurumenekoa hurrenez hurren. Azkenik, lanean zehar aztertutakoa kontuan hartuta zein ondoriotara iritsi garen adieraziko da.

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This paper aims to investigate companies' environmental, social, governance (ESG), and financial implications of their commitment to the United Nations Global Compact (UNGC). The focus is placed on companies operating in the three countries with the highest number of UNGC participants: Spain, France, and Japan. The results clearly reveal that adoption of the UNGC often requires an organizational change that fosters stakeholder engagement, ultimately resulting in improvements in companies' ESG performance. Additionally, the results reveal that ESG performance has a significant impact on financial performance for companies that adopted the principles of the UNGC. These findings provide both non-financial and financial incentives to companies to commit to this voluntary corporate social responsibility (CSR) initiative, which will have important implications on companies' strategic management policies that aim to foster sustainable businesses and community development. Finally, the linkages between the UNGC-committed companies' ESG and financial performance may be influenced by geographical spread, mainly due to the appearance of differences in the institutional, societal, and cultural settings.