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排序方式: 共有263条查询结果,搜索用时 46 毫秒
1.
Belli F. Jedrzejowicz P. 《IEEE transactions on pattern analysis and machine intelligence》1991,17(3):310-312
An approach to the optimization of software reliability is proposed. The emphasis is put on the software redundancy to achieve fault tolerance, i.e. the results of the optimization process are used to determine the optimal structure of the software to be developed. Two optimization models are formulated covering, respectively, modified recovery block scheme and multiversion programming approaches. Both cases are illustrated by simple examples. The models show that it is possible to formulate and solve some software related reliability optimization problems. They further show that the concept of redundancy to achieve fault tolerance (basic for the traditional theory of reliability) can be used in the field of software reliability optimization 相似文献
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Belli Robert F.; Windschitl Paul D.; McCarthy Thomas T.; Winfrey Steve E. 《Canadian Metallurgical Quarterly》1992,18(2):356
Suggests that detecting memory impairment with the modified test relies on long retention intervals that provide the necessary forgetting of event information for impairing effects of postevent misinformation to occur. 288 Ss were tested in 4 experiments that presented event items centrally, introduced verbal postevent items to a misled condition, and used the modified test, but differed by using either short (15 min) or long (5–7 days) retention intervals. As evidenced by poorer misled than control test performances, memory impairment only occurred with long retention intervals. Retrieval- and storage-based versions of memory-impairment hypotheses are assessed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Maria Augusta de Luca Taís Espíndola Machado Renan Beretta Notti Marly Maldaner Jacobi 《应用聚合物科学杂志》2004,92(2):798-803
Hybrid materials were synthesized from epoxidized (68, 43, or 14%) styrene–butadiene rubber (SBR) and the hydrolysis product of tetraethoxysilane (TEOS) in situ under ultrasonic irradiation. The products were characterized with thermal analysis (differential scanning calorimetry and thermogravimetric analysis), stress–strain tests, scanning electron microscopy (including energy‐dispersive spectrometry), and swelling in tetrahydrofuran and water. The most transparent were those prepared from SBR with the highest degree of epoxidation, whereas those obtained from less epoxidized SBR and with larger amounts of TEOS showed distinct phases that could be considered two hybrid phases (one rich in TEOS and another rich in SBR). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 798–803, 2004 相似文献
6.
Renan Felicio dos Reis Joao Sergio Cordeiro Xavier Font Cali Laguna Achon 《Drying Technology》2020,38(10):1247-1260
AbstractSewage treatment can be classified into three phases: liquid, gaseous, and solid. Treatment of solids is performed in several steps, and the greatest difficulty in removing water from sewage sludge is due to the bound water present in the sludge. Thus, biodrying, a drying method that can be classified as biological, has been recently applied to treat this type of waste. This review paper aims to report and compile data from 49 biodrying assays of sewage sludge found in the literature (through the present, 2019) into one synthesis table, to discuss and compare the numerous variables found in these papers and their implications for biodrying, and to suggest possibilities for future research. This paper additionally intends to improve knowledge of biodrying and to consequently contribute to the monitoring and understanding of the process. 相似文献
7.
从分子热力学基础出发提出一个适用于固体-超临界流体相平衡的理论模型,溶液中溶质的化学位分解为无限稀溶液化学位及溶质浓度效应两部.无限稀溶液化学位由简化的Oz方程计算,其中包括斥力贡献、局部组成及长程引力项浓度对化学位的贡献由作者根据Kirkwood-Buff溶液理论提出的修正Wilson模型计算.用45个二元系862个数据点对此模型进行检验并和PR方程(vdw-2混合规则)计算结果进行比较,本模型的平均绝对误差为11.7%,而PR方程的结果为14.9%,对极性溶剂体系的计算结果有显著改善.用此模型直接推算的萘-Co_2体系萘的偏摩尔焓和文献数据相吻合 相似文献
8.
The effect of actinomycin-D (AMD) on radiation damage repair was studied in plateau phase V79 Chinese hamster cells. Sublethal radiation damage repair, as demonstrated by survival fluctuations following two x-ray exposures separted by time, was observed in our plateau phase cells. Plateau phase cells exposed to 0.01-0.04 mug/ml AMD (a nontoxic regimen to 8 hours) between x-ray exposures were less able to repair sublethal damage. If plateau phase cells were plated at low dilutions into fresh medium (conditions for resuming exponential growth) immediately after the first x-ray dose, and exposed to 0.01--0.04 mug/ml AMD until the second dose, inhibition of sublethal damage repair and additional cell killing were observed particularly at 0.04 mug/ml AMD. It is suggested that radiation-drug damage interactions should be studied in plateau phase cells and in cells resuming exponential growth after plateau phase (possibly analogous to "recruitment"), as well as in exponential phase cultures. 相似文献
9.
Afzan A. Ayoub Abdel H. Mahmoud Juliana S. Ribeiro Arwa Daghrery Jinping Xu J. Christopher Fenno Anna Schwendeman Hajime Sasaki Renan Dal-Fabbro Marco C. Bottino 《International journal of molecular sciences》2022,23(22)
This study was aimed at engineering photocrosslinkable azithromycin (AZ)-laden gelatin methacryloyl fibers via electrospinning to serve as a localized and biodegradable drug delivery system for endodontic infection control. AZ at three distinct amounts was mixed with solubilized gelatin methacryloyl and the photoinitiator to obtain the following fibers: GelMA+5%AZ, GelMA+10%AZ, and GelMA+15%AZ. Fiber morphology, diameter, AZ incorporation, mechanical properties, degradation profile, and antimicrobial action against Aggregatibacter actinomycetemcomitans and Actinomyces naeslundii were also studied. In vitro compatibility with human-derived dental pulp stem cells and inflammatory response in vivo using a subcutaneous rat model were also determined. A bead-free fibrous microstructure with interconnected pores was observed for all groups. GelMA and GelMA+10%AZ had the highest fiber diameter means. The tensile strength of the GelMA-based fibers was reduced upon AZ addition. A similar pattern was observed for the degradation profile in vitro. GelMA+15%AZ fibers led to the highest bacterial inhibition. The presence of AZ, regardless of the concentration, did not pose significant toxicity. In vivo findings indicated higher blood vessel formation, mild inflammation, and mature and thick well-oriented collagen fibers interweaving with the engineered fibers. Altogether, AZ-laden photocrosslinkable GelMA fibers had adequate mechanical and degradation properties, with 15%AZ displaying significant antimicrobial activity without compromising biocompatibility. 相似文献
10.
Giacomo Lazzarino Valentina Di Pietro Marco Rinaudo Zsuzsanna Nagy Nicholas M. Barnes Lars Bruce Stefano Signoretti Renata Mangione Miriam Wissam Saab Barbara Tavazzi Antonio Belli Giuseppe Lazzarino Angela Maria Amorini Ann Logan 《International journal of molecular sciences》2022,23(15)
In a previous study, we found that administration of ILB®, a new low molecular weight dextran sulphate, significantly improved mitochondrial functions and energy metabolism, as well as decreased oxidative/nitrosative stress, of brain tissue of rats exposed to severe traumatic brain injury (sTBI), induced by the closed-head weight-drop model of diffused TBI. Using aliquots of deproteinized brain tissue of the same animals of this former study, we here determined the concentrations of 24 amino acids of control rats, untreated sTBI rats (sacrificed at 2 and 7 days post-injury) and sTBI rats receiving a subcutaneous ILB® administration (at the dose levels of 1, 5 and 15 mg/kg b.w.) 30 min post-impact (sacrificed at 2 and 7 days post-injury). Additionally, in a different set of experiments, new groups of control rats, untreated sTBI rats and ILB®-treated rats (administered 30 min after sTBI at the dose levels of 1 or 5 mg/kg b.w.) were studied for their neurocognitive functions (anxiety, locomotor capacities, short- and long-term memory) at 7 days after the induction of sTBI. Compared to untreated sTBI animals, ILB® significantly decreased whole brain glutamate (normalizing the glutamate/glutamine ratio), glycine, serine and γ-aminobutyric acid. Furthermore, ILB® administration restored arginine metabolism (preventing nitrosative stress), levels of amino acids involved in methylation reactions (methionine, L-cystathionine, S-adenosylhomocysteine), and N-acetylaspartate homeostasis. The macroscopic evidences of the beneficial effects on brain metabolism induced by ILB® were the relevant improvement in neurocognitive functions of the group of animals treated with ILB® 5 mg/kg b.w., compared to the marked cognitive decline measured in untreated sTBI animals. These results demonstrate that ILB® administration 30 min after sTBI prevents glutamate excitotoxicity and normalizes levels of amino acids involved in crucial brain metabolic functions. The ameliorations of amino acid metabolism, mitochondrial functions and energy metabolism in ILB®-treated rats exposed to sTBI produced significant improvement in neurocognitive functions, reinforcing the concept that ILB® is a new effective therapeutic tool for the treatment of sTBI, worth being tested in the clinical setting. 相似文献