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51.
Tristan Roussillon Author Vitae Isabelle Sivignon Author Vitae Author Vitae 《Pattern recognition》2010,43(1):37-46
This paper focuses on the design of an effective method that computes the measure of circularity of a part of a digital boundary. An existing circularity measure of a set of discrete points, which is used in computational metrology, is extended to the case of parts of digital boundaries. From a single digital boundary, two sets of points are extracted so that the circularity measure computed from these sets is representative of the circularity of the digital boundary. Therefore, the computation consists of two steps. First, the inner and outer sets of points are extracted from the input part of a digital boundary using digital geometry tools. Next, the circularity measure of these sets is computed using classical tools of computational geometry. It is proved that the algorithm is linear in time in the case of convex parts thanks to the specificity of digital data, and is in O(nlogn) otherwise. Experiments done on synthetic and real images illustrate the interest of the properties of the circularity measure. 相似文献
52.
Ohne Zusammenfassung 相似文献
53.
G. Schultze-Dewitz H. Willeitner K. Rügge W. Schweers H. Augustin D. Fengel G. Weißmann L. Plath H. Kübler H. Kolb 《Holz als Roh- und Werkstoff》1967,25(11):441-443
Ohne Zusammenfassung 相似文献
54.
Jay G. Slowik K. Stainken Paul Davidovits L. R. Williams J. T. Jayne C. E. Kolb 《Aerosol science and technology》2013,47(12):1206-1222
Composition, shape factor, size, and fractal dimension of soot aerosol particles generated in a propane/O2, flame were determined as a function of the fuel equivalence ratio (φ). Soot particles were first size-selected by a differential mobility analyzer (DMA) and then analyzed by an Aerodyne aerosol mass spectrometer (AMS). The DMA provides particles of known mobility diameter (dm ). The AMS quantitatively measures the mass spectrum of the nonrefractory components of the particles and also provides the vacuum aerodynamic diam eter (dva ) corresponding to the particles of known mobility diameter. The measured dm, dva , and nonrefractory composition are used in a system of equations based on the formulation presented in the companion article to estimate the particle dynamic shape factor, total mass, and black carbon (BC) content. Fractal dimension was estimated based on the mass-mobility relationship. Two types of soot particles were observed depending on the fuel equivalence ratio. Type 1: for φ < 4 (lower propane/O2), dva ; was nearly constant and independent of dm . The value of dva increased with increasing φ. Analysis of the governing equations showed that these particles were highly irregular (likely fractal aggregates), with a dynamic shape factor that increased with dm and φ. The fractal dimension of these particles was approximately 1.7. These particles were composed mostly of BC, with the organic carbon content increasing as φ increased. At φ = 1.85, the particles were about 90% BC, 5% PAH, and 5% aliphatic hydrocarbon (particle density = 1.80 g/cm3). Type 2: for φ > 4 (high propane/O2), dva was linearly proportional to dm . Analysis of the governing equations showed that these particles were nearly spherical (likely compact aggregates), with a dynamic shape factor of 1.1 (versus 1 for a sphere) and a fr actal dimension of 2.95 (3 for a sphere). These particles were composed of about 50% PAH, 45% BC, and 5% aliphatic hydrocarbons (particle density = 1.50 g/cm3). These results help interpret some measurement s obtained in recent field studies. 相似文献
55.
G. Schultze-Dewits A. Dosoudil D. Fongel P. Kisseloff J. Horn D. Fengel G. Weißmann A. Burmester K. Rügge H. Kolb G. Hägele 《Holz als Roh- und Werkstoff》1968,26(6):232-235
Ohne Zusammenfassung 相似文献
56.
Results of allogeneic bone marrow transplants for leukemia using donors other than HLA-identical siblings 总被引:1,自引:0,他引:1
R Szydlo JM Goldman JP Klein RP Gale RC Ash FH Bach BA Bradley JT Casper N Flomenberg JL Gajewski E Gluckman PJ Henslee-Downey JM Hows N Jacobsen HJ Kolb B Lowenberg T Masaoka PA Rowlings PM Sondel DW van Bekkum JJ van Rood MR Vowels MJ Zhang MM Horowitz 《Canadian Metallurgical Quarterly》1997,15(5):1767-1777
PURPOSE: To compare outcomes of bone marrow transplants for leukemia from HLA-identical siblings, haploidentical HLA-mismatched relatives, and HLA-matched and mismatched unrelated donors. PATIENTS: A total of 2,055 recipients of allogeneic bone marrow transplants for chronic myelogenous leukemia (CML), acute myelogenous leukemia (AML), and acute lymphoblastic leukemia (ALL) were entered onto the study. Transplants were performed between 1985 and 1991 and reported to the International Bone Marrow Transplant Registry (IBMTR). Donors were HLA-identical siblings (n = 1,224); haploidentical relatives mismatched for one (n = 238) or two (n = 102) HLA-A, -B, or -DR antigens; or unrelated persons who were HLA-matched (n = 383) or mismatched for one HLA-A, -B, or -DR antigen (n = 108). HLA typing was performed using serologic techniques. RESULTS: Transplant-related mortality was significantly higher after alternative donor transplants than after HLA-identical sibling transplants. Among patients with early leukemia (CML in chronic phase or acute leukemia in first remission), 3-year transplant-related mortality (+/-SE) was 21% +/- 2% after HLA-identical sibling transplants and greater than 50% after all types of alternative donor transplants studied. Among patients with early leukemia, relative risks of treatment failure (inverse of leukemia-free survival), using HLA-identical sibling transplants as the reference group, were 2.43 (P < .0001) with 1-HLA-antigen-mismatched related donors, 3.79 (P < .0001) with 2-HLA-antigen-mismatched related donors, 2.11 (P < .0001) with HLA-matched unrelated donors, and 3.33 (P < .0001) with 1-HLA-antigen-mismatched unrelated donors. For patients with more advanced leukemia, differences in treatment failure were less striking: 1-HLA-antigen-mismatched relatives, 1.22 (P = not significant [NS]); 2-HLA-antigen-mismatched relatives, 1.81 (P < .0001); HLA-matched unrelated donors, 1.39 (P = .002); and 1-HLA-antigen-mismatched unrelated donors, 1.63 (P = .002). CONCLUSION: Although transplants from alternative donors are effective in some patients with leukemia, treatment failure is higher than after HLA-identical sibling transplants. Outcome depends on leukemia state, donor-recipient relationship, and degree of HLA matching. In early leukemia, alternative donor transplants have a more than twofold increased risk of treatment failure compared with HLA-identical sibling transplants. This difference is less in advanced leukemia. 相似文献
57.
J Rudi C Kolb M Maiwald I Zuna A von Herbay PR Galle W Stremmel 《Canadian Metallurgical Quarterly》1997,42(8):1652-1659
Infection with Helicobacter pylori is associated with the development of gastric cancer. To study whether the infection with H. pylori strains expressing the vacuolating cytotoxin (VacA) and/or the cytotoxin-associated protein (CagA) is associated with an increased risk of developing gastric adenocarcinoma, sera of 90 patients with gastric cancer and 90 matched controls with cardiovascular diseases were investigated for the presence of antibodies to VacA and CagA by immunoblot. Although no significant difference in the overall H. pylori seropositivity was found between cancer patients and controls, antibodies against VacA or CagA were significantly more frequent in cancer patients than in control subjects. Seventy-five (97.4%) of 77 H. pylori-positive patients in the cancer group, but only 60 (84.5%) of 71 H pylori-positive control patients had antibodies against either VacA or CagA (chi 2 = 6.63; relative risk, 2.00; 95% confidence interval, 1.18-3.39; P = 0.01). The presence of antibodies against VacA or CagA alone was also associated with an increased cancer risk (92.2% vs 80.3%; chi 2 = 5.30; relative risk, 1.74; 95% confidence interval, 1.08-2.78; P = 0.021, for VacA; and 87.0% vs 74.6%; chi 2 = 4.90; relative risk, 1.61; 95% confidence interval, 1.06-2.45; P = 0.037, for CagA). The relative risk for gastric cancer was mainly elevated in patients under 65 years, but not in patients at or over 65 years. There is evidence that infection with VacA- or CagA-producing H. pylori strains increases the risk of developing gastric cancer, especially in younger patients. 相似文献
58.
S. Neumaier H. H. Gutbrod T. Hubbeling B. W. Kolb M. L. Purschke M. Ippolitov V. Manko G. Mgebrishvili A. Nijanin Y. Sibiryak A. Tsvetkov A. Vinogradov C. Barlag C. Blume E. -M. Bohne D. Bucher A. Claussen T. Peitzmann G. Schepers H. Schlagheck 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1995,360(3):593-597
We describe a new high voltage power supply, developed for the leadglass calorimeter of the WA98 experiment at CERN. The high voltage is produced for each of the 10 080 photomultiplier tubes of the detector individually, by the same number of active bases with on-board Greinacher voltage multipliers. The full VME-based HV controller system, which addresses each base via bus cables once per second, is miniaturized and fits into a single VME crate. The main advantages of this approach are the low heat dissipation, the considerably reduced amount of cabling and cost, as well as the high stability and low noise of the system. 相似文献
59.
Research issues in developing compact pulsed power for high peak power applications on mobile platforms 总被引:3,自引:0,他引:3
Gaudet J.A. Barker R.J. Buchenauer C.J. Christodoulou C. Dickens J. Gundersen M.A. Joshi R.P. Krompholz H.G. Kolb J.F. Kuthi A. Laroussi M. Neuber A. Nunnally W. Schamiloglu E. Schoenbach K.H. Tyo J.S. Vidmar R.J. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2004,92(7):1144-1165
Pulsed power is a technology that is suited to drive electrical loads requiring very large power pulses in short bursts (high-peak power). Certain applications require technology that can be deployed in small spaces under stressful environments, e.g., on a ship, vehicle, or aircraft. In 2001, the U.S. Department of Defense (DoD) launched a long-range (five-year) Multidisciplinary University Research Initiative (MURI) to study fundamental issues for compact pulsed power. This research program is endeavoring to: 1) introduce new materials for use in pulsed power systems; 2) examine alternative topologies for compact pulse generation; 3) study pulsed power switches, including pseudospark switches; and 4) investigate the basic physics related to the generation of pulsed power, such as the behavior of liquid dielectrics under intense electric field conditions. Furthermore, the integration of all of these building blocks is impacted by system architecture (how things are put together). This paper reviews the advances put forth to date by the researchers in this program and will assess the potential impact for future development of compact pulsed power systems. 相似文献
60.
Verena Liebau-Kunzmann Claudia Fasel Robert Kolb Ralf Riedel 《Journal of the European Ceramic Society》2006,26(16):3897-3901
Lithium containing silicon carbonitride ceramics (SiCN:Li) were synthesized via precursor-to-ceramic-transformation of Li-containing (poly)silazanes. The precursors were obtained by lithiation of the model compound 2,4,6-trimethyl-2,4,6-trivinylcyclotrisilazane and of a commercial poly(organosilazane) VL20® with n-butyllithium in different molar ratios. According to Raman spectroscopic measurements, lithiation takes place at the NH groups of the molecular organosilazane structure. If the amount of n-BuLi exceeds the stoichiometric amount of NH groups, addition of n-BuLi at the vinyl groups (attached as substituents at the Si atoms of the silazane) occurs. Thermal analysis coupled with in situ mass spectrometry evidenced the loss of methane and hydrogen as the main gaseous by-products formed during the precursor-to-ceramic-transformation. The ceramization process is completed at 1100 °C in argon and yielded Li-containing silicon carbonitride, SiCN:Li. X-ray powder diffraction revealed that the resulting SiCN:Li ceramics were basically amorphous and contained LiSi2N3 as a crystalline phase with increasing amount of Li. Possible applications of the new SiCN:Li ceramics are seen in the field of Li-ion batteries as alternative anode or solid electrolyte material. 相似文献