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排序方式: 共有2110条查询结果,搜索用时 15 毫秒
101.
Fran?ois Destrempes Max Mignotte Jean-Fran?ois Angers 《IEEE transactions on image processing》2005,14(8):1096-1108
We propose a new stochastic algorithm for computing useful Bayesian estimators of hidden Markov random field (HMRF) models that we call exploration/selection/estimation (ESE) procedure. The algorithm is based on an optimization algorithm of O. Fran?ois, called the exploration/selection (E/S) algorithm. The novelty consists of using the a posteriori distribution of the HMRF, as exploration distribution in the E/S algorithm. The ESE procedure computes the estimation of the likelihood parameters and the optimal number of region classes, according to global constraints, as well as the segmentation of the image. In our formulation, the total number of region classes is fixed, but classes are allowed or disallowed dynamically. This framework replaces the mechanism of the split-and-merge of regions that can be used in the context of image segmentation. The procedure is applied to the estimation of a HMRF color model for images, whose likelihood is based on multivariate distributions, with each component following a Beta distribution. Meanwhile, a method for computing the maximum likelihood estimators of Beta distributions is presented. Experimental results performed on 100 natural images are reported. We also include a proof of convergence of the E/S algorithm in the case of nonsymmetric exploration graphs. 相似文献
102.
Max Nankervis 《Urban Policy and Research》2013,31(2):65-69
During the last decade or so, several Australian governments have developed controls to preserve the built environment. The necessity of such controls derives from the form of the development of industrial capitalism over the last century, and particularly the more recent development of the ‘corporate city’. The recent development of specific site controls and planning legislation implicitly recognises this and reflects the ‘public good’ nature of conservation, and the necessity for inclusion in the general twentieth century state intrusion. Conservation is thus, it is concluded, more a question of political economy than taste and aesthetics. 相似文献
103.
Dominik Kiem Michael Leisch Daniel Neureiter Theresa Haslauer Alexander Egle Thomas Melchardt Max S. Topp Richard Greil 《International journal of molecular sciences》2021,22(11)
Background: Chimeric antigen receptor (CAR) T-cells are changing the therapeutic landscape of hematologic malignancies. Severe side effects include cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS), but prolonged cytopenia has also been reported. The underlying mechanism for prolonged cytopenia is poorly understood so far. Cases: Severe pancytopenia with grade 2-3 anemia was marked 2–3 months after treatment. Laboratory evaluation revealed undetectable levels of haptoglobin with increased reticulocyte counts. Coomb’s tests were negative, no schistocytes were detected on blood smear, and infectious causes were ruled out. Increased erythropoiesis without lymphoma infiltration was noted on bone marrow biopsy. A spontaneous increase in haptoglobin and hemoglobin levels was observed after several weeks. For one patient, peripheral CAR-T levels were monitored over time. We observed a decline at the same time as hemoglobin levels began to rise, implying a potential causality. Conclusion: To our knowledge, we describe the first two cases of Coombs-negative hemolytic anemia after CAR-T treatment for B-cell lymphoma. We encourage routine monitoring for hemolytic anemia after CAR-T treatment and also encourage further investigations on the underlying mechanism. 相似文献
104.
Training psychology students to treat patients with serious and persistent mental illness (SPMI) can provide an excellent opportunity for psychologists to help an historically disenfranchised and ignored population. With proper training, psychologists can play an important role in the development, provision, and administration of services to people with SPMI. We outline some of the issues to be considered in developing such a training program for practicum students, discuss the clinical skills and systemic issues that need to be mastered at the graduate level, and delineate the process by which this can be achieved in an inpatient, acute-care setting. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
105.
106.
Addition of small amounts (0.5-10 vol%) of multiwall carbon nanotubes (CNT) to thermoplastic elastomer Morthane produced polymer nanocomposites with high electrical conductivity (σ∼1-10 S/cm), low electrical percolation (?∼0.005) and enhancement of mechanical properties including increased modulus and yield stress without loss of the ability to stretch the elastomer above 1000% before rupture. In situ X-ray scattering during deformation indicated that these mechanical enhancements arise not only from the CNTs, but also from their impact on soft-segment crystallization. The deformation behavior after yielding of the nanocomposites, irrespective of CNT concentration, is similar to the unfilled elastomer, implying that the mechanistics of large deformation is mainly governed by the matrix. The relative enhancement of the Young's modulus of the nanocomposites is comparable to other elastomeric nanocomposites, implying that to the first order specific chemical details of the elastomeric system is unimportant. 相似文献
107.
Max Toepler VDE 《Electrical Engineering (Archiv fur Elektrotechnik)》1936,30(10):663-670
Zusammenfassung Auch Grenzübergänge ohne Funkenbildung können zur Spannungsmessung dienen (Grenzspannungen); Tafeln für eine ersatzweise Benutzung der Grenzstromstärken sind erwünscht. Zur vollen Ausnutzung der möglichen Meßgenauigkeit ist auf die Feinstruktur der Übergänge Rücksicht zu nehmen; jede einzelne Grenzkurve zerfällt in Stufen mit Knicken und Sprungstellen, deren Lage von der Art der Spannungserzeugung sowie den Konstanten der Zuleitung und nicht nur (selbst bei eindeutiger Käfigung) von den Konstanten der Meßfunkenstrecke abhängig ist.Die Forderung, daß beim Übergange eine Funkenbildung stattfindet, beschränkt zudem die Auswahl und gibt der Elektrodenkapazität erhöhte Bedeutung. Jede Versuchsanordnung besitzt genau genommen eine eigenc Eichtabelle des zugehörigen Funkenspannungsverlaufes. 相似文献
108.
Analysis of exempt paint solvents by gas chromatography using solid-phase microextraction 总被引:1,自引:0,他引:1
Rosemarie R. Bodrian Albert C. Censullo Dane R. Jones Mark J. Rashkin Max T. Wills 《Journal of Coatings Technology》2000,72(900):69-74
Acetone, methyl acetate, and parachlorobenzotrifluoride (PCBTF or Oxsol? 100) have been exempted as VOC solvents by the U.S.
Environmental Protection Agency. In measuring coating VOC content, separate methods for determining exempt solvents are required.
One such method utilizes solid-phase microextraction (SPME) to sample the headspace of solvent-based coatings to which the
surrogates acetone-d6, methyl acetate-d3, and/or metachlorobenzotrifluoride have been added. The sampled exempt coating solvents
are thermally desorbed and analyzed using gas chromatography with flame ionization or mass spectral detection. The SPME headspace
method has also been used to analyze MEK, butyl acetate, tert-butyl acetate, toluene, and xylene in solventborne coatings,
and alcohols in waterborne systems. This paper presents the results obtained for acetone and toluene in a large number of
aerosol paints. Additionally, the results from a round-robin study for acetone, methyl acetate, and parachlorobenzotrifluoride
in commercial solvent-based coatings are reported. 相似文献
109.
K. Rastle and M. Coltheart (1999; see also M. Coltheart & K. Rastle, 1994) reported data demonstrating that the cost of irregularity in reading aloud low-frequency exception words is modulated by the position of the irregularity in the word. They argued that these data implicated a serial process and falsified all models of reading aloud that operate solely in parallel, a conclusion that M. Zorzi (2000) challenged by successfully simulating the position of irregularity effect with such a model. Zorzi (2000) further claimed that a reanalysis of K. Rastle and A Coltheart's (1999) data demonstrates sensitivity to grapheme-phoneme consistency (which he claimed was confounded across the position of irregularity manipulation) rather than the use of a serial process. Here, the authors argue that M. Zorzi's (2000) reanalyses were inappropriate and reassert that K. Rastle and A Coltheart's (1999) findings are evidence for serial processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Max Skalicky 《Electrical Engineering (Archiv fur Elektrotechnik)》1940,34(9):541-543
Zusammenfassung Nach Festlegung eines willkürlichen Strom- und Spannungsmaßstabes wird zuerst das Galvanometerrechteck gezeichnet und an dieses unter Winkeln, deren Tangens den ohmschen Widerständen der Brückenzweige entsprechen, Strahlen gezogen.Durch einfache Konstruktion wird das Umgrenzungsrechteck gefunden. Die Ströme und Spannungen sind in dem vollständigen Diagramm durch Strecken dargestellt. Bei änderung eines Brückenwiderstandes kann die jeweils auftretende Galvanometerspannung sofort an der Strecke E0H abgelesen werden. 相似文献