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71.
Graph mining for discovering infrastructure patterns in configuration management databases 总被引:1,自引:1,他引:0
Pranay Anchuri Mohammed J. Zaki Omer Barkol Ruth Bergman Yifat Felder Shahar Golan Arik Sityon 《Knowledge and Information Systems》2012,33(3):491-522
A configuration management database (CMDB) can be considered to be a large graph representing the IT infrastructure entities and their interrelationships. Mining such graphs is challenging because they are large, complex, and multi-attributed and have many repeated labels. These characteristics pose challenges for graph mining algorithms, due to the increased cost of subgraph isomorphism (for support counting) and graph isomorphism (for eliminating duplicate patterns). The notion of pattern frequency or support is also more challenging in a single graph, since it has to be defined in terms of the number of its (potentially, exponentially many) embeddings. We present CMDB-Miner, a novel two-step method for mining infrastructure patterns from CMDB graphs. It first samples the set of maximal frequent patterns and then clusters them to extract the representative infrastructure patterns. We demonstrate the effectiveness of CMDB-Miner on real-world CMDB graphs, as well as synthetic graphs. 相似文献
72.
Tunneling Density of States of Indium Oxide Films Through the Superconductor to Insulator Transition
D. Sherman G. Kopnov E. Farber D. Shahar A. Frydman 《Journal of Superconductivity and Novel Magnetism》2013,26(5):1473-1477
We present planar tunneling junction spectroscopy measurements on disordered amorphous indium oxide films on both sides of the superconductor–insulator transition. Our measurements directly reveal a superconducting gap in the insulating phase. The measured energy gap has the same energy scale on both sides of the transition. Unlike the case of granular films, the tunneling curves cannot be fitted to the BCS density of state expression, even when introducing a broadening parameter to account for nonthermal broadening sources. The results are consistent with the presence of superconducting islands of which superconducting properties depend on film disorder and on the carrier density of the superconducting material. 相似文献
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DK Arnett JM Sprafka PG McGovern DR Jacobs E Shahar M McCarty RV Luepker 《Canadian Metallurgical Quarterly》1998,88(8):1230-1233
OBJECTIVES: The purpose of this study was to describe trends in the prevalence of cigarette smoking between 1980 through 1982 and 1990 through 1992 in Minneapolis and St. Paul, Minn. METHODS: Three population-based surveys were conducted among adults 25 to 74 years of age in 1980 through 1982, 1985 through 1987, and 1990 through 1992. RESULTS: Overall age-adjusted prevalences of cigarette smoking declined significantly between 1980-1982 and 1985-1987 and between 1985-1987 and 1990-1992. Serum thiocyanate, a biochemical marker for tobacco use, also declined significantly over the 3 periods. CONCLUSIONS: Favorable trends in smoking prevalence and cigarette consumption among smokers were observed, but disturbing trends in some smoking behaviors were also noted. 相似文献
75.
Granot E Sternklar S Chayet H Ben-Ezra S Narkiss N Shahar N Sher A Tsadka S 《Applied optics》2005,44(23):4959-4964
For the first time, to our knowledge, a highly robust, high-bit-rate (10 Gbit/s) wavelength converter that is based on a narrow Brillouin filter is reported. The conversion takes place in a semiconductor optical amplifier (SOA) in a cross-gain-phase process. The SOA operates in a weak-modulation mode, and the exiting signal undergoes a dc reduction with a narrow spectral filter. In our system we perform spectrally narrow filtering by using a long Brillouin grating. 相似文献
76.
CD Enk S Elad A Vexler J Kapelushnik R Gorodetsky M Kirschbaum 《Canadian Metallurgical Quarterly》1998,22(12):1179-1183
Chronic graft-versus-host disease (cGVHD) is a major complication of allogeneic bone marrow transplantation. Immunosuppressive treatment regimens carry the potential of causing severe morbidity and mortality, so that additional modes of therapy with fewer side-effects are clearly needed. Five cGVHD patients (sclerodermoid cGVHD in two patients, lichenoid cGVHD in one patient and intraoral cGVHD in two patients), who had not responded to standard immunosuppressive drugs, were treated with adjuvant UVB phototherapy. The patient with lichenoid cGVHD experienced complete clearing of cutaneous lesions, whereas both patients with sclerodermoid cGVHD experienced significant relief of pruritus, but showed no change of the sclerodermoid skin lesions. Intraoral lesions cleared in one patient. The effects of UVB phototherapy were furthermore documented by measurement of skin viscoelasticity and mouth opening. No side-effects were encountered. This preliminary study suggests that UVB phototherapy is useful as an adjuvant therapeutic modality in intraoral and cutaneous lichenoid cGVHD. 相似文献
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Elad D 《Journal of food protection》2005,68(6):1302-1305
Throughout the last decades of the 20th century, the biological threat evolved from primarily a government-controlled weapon to a tool of terrorism. One of the consequences of this trend is the near impossibility of foreseeing when and how an act of bioterrorism will occur. The suitability of food products for such an act stems from the multitude of microorganisms that may be used for contamination and the vulnerability of the products during and after processing. Tests that would enable the detection of a large variety of microorganisms quickly, reliably, and economically should also provide satisfactory means to prevent acts of malicious biocontamination of food products. Until such means become available, a priority-based approach to the problem is probably the most practical. Priorities should be determined based on a systematic risk assessment to define the relative likelihood of a certain microorganism being used in an act of malicious food contamination. Criteria to be evaluated are availability, weaponization processes, delivery of an effective dose, probability of early detection, and the microorganism's resistance to the conditions to which it will be exposed. Because the results of such an assessment may vary according to prevailing conditions, the assessment must be based on the existing circumstances. The results of the assessment should then be applied to the various procedures of food processing, which should further reduce the number of potential microbial threats. Existing methods of screening food for contaminating microorganisms and existing food safety and security procedures such as hazard analysis and critical control point programs may have to be modified to become suitable for the detection of acts of bioterrorism. 相似文献
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