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81.
Receding horizon control is emerging as a very promising technique for the centralized control of fleets of vehicles on land, sea, and in the air. We present a sufficient condition for collision avoidance within a fleet under receding horizon control, over an indefinite period of operation.  相似文献   
82.
This work investigates the impact of various processing parameters on the leakage current of in situ P-doped Si1−xCx embedded source/drain (S/D) junctions, i.e., the carbon content x (%) and the thermal budget used either before or after the selective epitaxial deposition. It is shown that while the area leakage current density, generated by defects in the depletion region is not affected by the epitaxial process or the strain in the substrate, the perimeter leakage current density (JP) increases with x. From the stronger reverse bias dependence of JP, it is derived that a higher electric field exists along the junction periphery. This is confirmed by capacitance-voltage (C-V) measurements, demonstrating a higher p-well B doping density for increasing x. It is believed that this originates from the strain dependence of the B diffusivity in the p-well region. No evidence of electrically active extended defect formation was found, so it is expected that the off-state current of embedded Si1−xCx S/D nMOSFETs will not be adversely affected by the selective epitaxial deposition.  相似文献   
83.
The reflection and magnetic reflection spectra, magnetic resistance, electrical properties, and equatorial Kerr effect in La0.7Ca0.3MnO3 crystals have been complexly investigated. The measurements have been performed in wide temperature and spectral ranges in magnetic fields up to 3.5 kOe. It has been found that magnetic reflection is a high-frequency response in the infrared spectral range to the colossal magnetore-sistance near the Curie temperature. Correlation between the field and temperature dependences of the magnetic reflection and colossal magnetoresistance has been revealed. The previously developed theory of the magnetorefractive effect for metallic systems makes it possible to explain the experimental data at the qualitative level. Both demerits of the theory of the magnetorefractive effect in application to the magnets and possible additional mechanisms responsible for the magnetic reflection are discussed.  相似文献   
84.
Despite the therapeutic efficacy of valproic acid towards numerous diseases, its poor bioavailability and systemic side effects pose significant barriers to long term treatment. In order to take advantage of controlled release implants of valproic acid, the drug was encapsulated into titania ceramic matrices via a sol-gel process. The integrity and structure of valproic acid-containing matrices were characterized through the use of FESEM, TEM, and BET analyses. In vitro controlled release studies and kinetic analyses were performed under ambient conditions (25 °C, atmospheric pressure) and controlled release behaviors were studied using a GC-MS method. Results showed first order dependence in the rate of valproic acid release as a function of drug concentrations in the titania ceramic device. A marked dependence on the surface area and pore size distribution with drug loading was also observed. This research opens new possibilities for the design of novel time-delayed controlled release systems for valproic acid encapsulates.  相似文献   
85.
A search for events with jets and missing transverse energy is performed in a data sample of pp collisions collected at √s=7 TeV by the CMS experiment at the LHC. The analyzed data sample corresponds to an integrated luminosity of 1.14 fb(-1). In this search, a kinematic variable α(T) is used as the main discriminator between events with genuine and misreconstructed missing transverse energy. No excess of events over the standard model expectation is found. Exclusion limits in the parameter space of the constrained minimal supersymmetric extension of the standard model are set. In this model, squark masses below 1.1 TeV are excluded at 95% C.L. Gluino masses below 1.1 TeV are also ruled out at 95% C.L. for values of the universal scalar mass parameter below 500 GeV.  相似文献   
86.
The results of the first search for long-lived gluinos produced in 7 TeV pp collisions at the CERN Large Hadron Collider are presented. The search looks for evidence of long-lived particles that stop in the CMS detector and decay in the quiescent periods between beam crossings. In a dataset with a peak instantaneous luminosity of 1×10(32) cm-2 s-1, an integrated luminosity of 10 pb-1, and a search interval corresponding to 62 hours of LHC operation, no significant excess above background was observed. Limits at the 95% confidence level on gluino pair production over 13 orders of magnitude of gluino lifetime are set. For a mass difference mg - mχ1(0) >100 GeV/c2, and assuming BR(g→gχ1(0))=100%, mg < 370 GeV/c2 are excluded for lifetimes from 10 μs to 1000 s.  相似文献   
87.
A search for three-jet hadronic resonance production in pp collisions at a center-of-mass energy of 7 TeV has been conducted by the CMS Collaboration at the LHC, using a data sample corresponding to an integrated luminosity of 35 pb(-1). Events with high jet multiplicity and a large scalar sum of jet transverse momenta are analyzed using a signature-based approach. The number of expected standard model background events is found to be in good agreement with the observed events. Limits on the cross section times branching ratio are set in a model of gluino pair production with an R-parity-violating decay to three quarks, and the data rule out such particles within the mass range of 200 to 280 GeV/c2.  相似文献   
88.
Electroweak production of the top quark is measured for the first time in pp collisions at √=7 TeV, using a data set collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 36 pb?1. With an event selection optimized for t-channel production, two complementary analyses are performed. The first one exploits the special angular properties of the signal, together with background estimates from the data. The second approach uses a multivariate analysis technique to probe the compatibility with signal topology expected from electroweak top-quark production. The combined measurement of the cross section is 83.6±29.8(stat+syst)±3.3(lumi) pb, consistent with the standard model expectation.  相似文献   
89.
A search for Z bosons in the μ(+)μ(-) decay channel has been performed in PbPb collisions at √S(NN)=2.76 TeV with the CMS detector at the LHC, in a 7.2 μb(-1) data sample. The number of opposite-sign muon pairs observed in the 60-120 GeV/c(2) invariant mass range is 39, corresponding to a yield per unit of rapidity (y) and per minimum bias event of [33.8±5.5(stat)±4.4(syst)]×10(-8), in the |y|<2.0 range. Rapidity, transverse momentum, and centrality dependencies are also measured. The results agree with next-to-leading order QCD calculations, scaled by the number of incoherent nucleon-nucleon collisions.  相似文献   
90.
Nonspecific high‐energy radiation for treatment of metastatic ovarian cancer is limited by damage to healthy organs, which can be mitigated by the use of radiosensitizers and image‐guided radiotherapy. Gold (Au) and tantalum oxide (TaOx) nanoparticles (NPs), by virtue of their high atomic numbers, find utility in the design of bimetallic NP systems capable of high‐contrast computed tomography (CT) imaging as well as a potential radiosensitizing effect. These two radio‐dense metals are integrated into dendritic mesoporous silica NPs (dMSNs) with radial porous channels for high surface‐area loading of therapeutic agents. This approach results in stable, monodispersed dMSNs with a uniform distribution of Au on the surface and TaOx in the core that exhibits CT attenuation up to seven times greater than iodine or monometallic dMSNs without either TaOx or Au. Tumor targeting is assessed in a metastatic ovarian cancer mouse model. Ex vivo micro‐CT imaging of collected tumors shows that these NPs not only accumulate at tumor sites but also penetrate inside tumor tissues. This study demonstrates that after intraperitoneal administration, rationally designed bimetallic NPs can simultaneously serve as targeted contrast agents for imaging tumors and to enhance radiation therapy in metastatic ovarian cancer.  相似文献   
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