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排序方式: 共有1004条查询结果,搜索用时 15 毫秒
61.
Teodor Gabriel Crainic Guido Perboli Miriam Pezzuto Roberto Tadei 《Computers & Operations Research》2007
In this paper, we address the issue of computing fast lower bounds for the Bin Packing problem, i.e., bounds that have a computational complexity dominated by the complexity of ordering the items by non-increasing values of their volume. We introduce new classes of fast lower bounds with improved asymptotic worst-case performance compared to well-known results for similar computational effort. Experimental results on a large set of problem instances indicate that the proposed bounds reduce both the deviation from the optimum and the computational effort. 相似文献
62.
Chiara Renso Miriam Baglioni Jose António F. de Macedo Roberto Trasarti Monica Wachowicz 《Knowledge and Information Systems》2013,37(2):331-362
The widespread use of mobile devices is producing a huge amount of trajectory data, making the discovery of movement patterns possible, which are crucial for understanding human behavior. Significant advances have been made with regard to knowledge discovery, but the process now needs to be extended bearing in mind the emerging field of behavior informatics. This paper describes the formalization of a semantic-enriched KDD process for supporting meaningful pattern interpretations of human behavior. Our approach is based on the integration of inductive reasoning (movement pattern discovery) and deductive reasoning (human behavior inference). We describe the implemented Athena system, which supports such a process, along with the experimental results on two different application domains related to traffic and recreation management. 相似文献
63.
Study of the effect of vintage,maturity degree,and irrigation on the amino acid and biogenic amine content of a white wine from the Verdejo variety
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64.
Albert Magrí Miriam Guivernau Guillermo Baquerizo Marc Viñas Francesc X Prenafeta‐Boldú Xavier Flotats 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2009,84(8):1202-1210
BACKGROUND: Manure treatment in intensive livestock farming is required to reduce the risk of negative environmental impacts by nitrogen disposal. Biological removal through intermittent aeration in a single bioreactor is a suitable method for this purpose. The characteristic operation based on the alternation of oxic/anoxic phases confers these systems with certain particularities in terms of process modelling and of understanding the microbial interactions. RESULTS: The performance of a sequencing batch reactor (SBR) treating raw liquid fraction of pig slurry (LFPS) under loading rates of 0.13 g N L?1 d?1 was studied. Three different aeration strategies were applied: (1) constant airflow; (2) dissolved oxygen (DO) set‐point; and (3) DO‐based real‐time control. The comparatively low aeration intensity applied throughout the third strategy resulted in the process being performed mainly via nitrite, implying a reduction on the requirements of organic carbon and oxygen. However, a decrease in the nitrification rate was observed under those conditions. Experimental results were satisfactorily simulated by a mathematical model focused on organic carbon and nitrogen removal. Microbial community structure analysis through denaturing gradient gel electrophoretic profiling of 16S rDNA genes showed that the aeration exerted a strong influence on the dominant microbial populations. The presence of the ammonia‐oxidizing species Nitrosomonas europaea, and of denitrifying bacteria related to Thauera sp. and Ralstonia sp., was detected in the strategy at low DO. CONCLUSION: Dependence of model statement and parameter values on the bioreactor operational patterns and piggery wastewater composition was evidenced. Oxygen limitation was responsible for a significant microbial shift in SBR treating LFPS. Copyright © 2009 Society of Chemical Industry 相似文献
65.
Vanessa Kohl Oliver Drews Victor Costina Miriam Bierbaum Ahmed Jawhar Henning Roehl Christel Weiss Susanne Brendel Helga Kleiner Johanna Flach Birgit Spiess Wolfgang Seifarth Daniel Nowak Wolf-Karsten Hofmann Alice Fabarius Henning D. Popp 《International journal of molecular sciences》2021,22(11)
Non-targeted effects (NTE) of ionizing radiation may initiate myeloid neoplasms (MN). Here, protein mediators (I) in irradiated human mesenchymal stromal cells (MSC) as the NTE source, (II) in MSC conditioned supernatant and (III) in human bone marrow CD34+ cells undergoing genotoxic NTE were investigated. Healthy sublethal irradiated MSC showed significantly increased levels of reactive oxygen species. These cells responded by increasing intracellular abundance of proteins involved in proteasomal degradation, protein translation, cytoskeleton dynamics, nucleocytoplasmic shuttling, and those with antioxidant activity. Among the increased proteins were THY1 and GNA11/14, which are signaling proteins with hitherto unknown functions in the radiation response and NTE. In the corresponding MSC conditioned medium, the three chaperones GRP78, CALR, and PDIA3 were increased. Together with GPI, these were the only four altered proteins, which were associated with the observed genotoxic NTE. Healthy CD34+ cells cultured in MSC conditioned medium suffered from more than a six-fold increase in γH2AX focal staining, indicative for DNA double-strand breaks, as well as numerical and structural chromosomal aberrations within three days. At this stage, five proteins were altered, among them IQGAP1, HMGB1, and PA2G4, which are involved in malign development. In summary, our data provide novel insights into three sequential steps of genotoxic signaling from irradiated MSC to CD34+ cells, implicating that induced NTE might initiate the development of MN. 相似文献
66.
67.
Ligianne Din Shirahigue Carmen J. Contreras-Castillo Miriam Mabel Selani Ana Paula Nadai Gerson Barreto Mourão Cláudio Rosa Gallo 《Food science and biotechnology》2011,20(5):1257-1264
Sensory analysis, instrumental color, pH, and thiobarbituric acid reactive substances (TBARS) were determined on cooked chicken
meat with and without grape seed extract during refrigerated storage. The effectiveness of extracts of winery grape residue
from the grape varieties ‘Isabel’ and ‘Niagara’ were tested to evaluate their effectiveness at delaying lipid oxidation in
cooked chicken meat and stored under refrigeration (4±1°C). The samples were aerobically and vacuum packaged and stored for
14 days. ‘Isabel’ grape extract (IGE) and ‘Niagara’ grape extract (NGE) proved effective at promoting oxidative stability
when applied at concentrations of 40 or 60 mg of gallic acid equivalents (GAE)/kg, with results similar to the synthetic antioxidant
butylated hydroxytoluene (BHT). The antioxidant efficiency of the extracts was highly dependent on the concentration used.
The addition of grape-residue extracts combined with vacuum packaging proved to be a good method for increasing lipid stability
in cooked chicken meat stored under refrigeration. 相似文献
68.
Objective: To investigate the relations among wives' labeling of their husbands' psychiatric disorder or brain injury as an organic illness, the husbands' perceived control over their disabilities, and the husbands' mental health. Participants: 57 male clients of the Department of Rehabilitation, Israel's Ministry of Defence (26 with a psychiatric disorder and 31 with a traumatic brain injury) and their wives. Measures: Illness Labeling Questionnaire, the Perceived Control Over Illness Questionnaire, and the Mental Health Inventory. Results: Husbands' mental health was low but did not differ according to disability; wives' labeling of husbands' condition was negatively related to the husbands' mental health; husbands' perceived control was positively related to their mental health for both disabilities. Conclusion: Organic illness labels, even when adopted by the wives of the persons with the disability, seem to be negatively related to that person's mental health, whereas perceived control over a mental disorder or a brain injury seems to contribute positively to mental health, independently of how the disorder or injury is labeled. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
Sonia Z. Viña Alicia Mugridge María A. García Ricardo M. Ferreyra Miriam N. Martino Alicia R. Chaves Noemí E. Zaritzky 《Food chemistry》2007,103(3):701-709
To extend shelf life, the effects of polyvinylchloride film (PVC) and edible coatings on quality aspects of refrigerated Brussels sprouts were studied. Starch-based coatings were formulated using glycerol (G), sorbitol (S) or glycerol plus sunflower oil (O). Sprouts so treated as well as uncoated ones were placed on expanded polystyrene trays. Combinations of PVC and coatings (treatments named G-PVC, S-PVC and O-PVC) were also tested. Uncovered trays were maintained as controls. All packages were stored at 0 °C for 42 days and samples were removed every 14 days to determine commercial acceptability, weight loss, surface colour (of sprouts’ heads and bases) and texture. Sprouts in all treatments maintained optimum quality conditions over the first 14 days. At the end of storage, browning of cut zones and losses in weight and firmness were minimised in PVC-packaged sprouts, particularly in G-PVC. Therefore, PVC and G-PVC treatments were selected to evaluate some nutritional quality components. Ascorbic acid and total flavonoid contents remained almost constant while radical scavenging activity increased after 42 days of storage. Thus, PVC and G-PVC treatments showed the best performance for long-term refrigerated storage of Brussels sprouts. 相似文献
70.
Examined 3 explanations of why participation in goal setting may lead to increased performance—the social factor of group discussion, the motivational factor of involvement in goal setting, and the cognitive factor of information. A 2?×?2?×?2 experimental design (low and high levels of group discussion, involvement, and information) was used to study 96 predominantly male white collar employees (aged 23–58 yrs) who worked on a simulated personnel selection task. Results indicate that the social and motivational factors of participation increased performance quantity, incidental learning, goal acceptance, group commitment, and satisfaction. The motivational and cognitive factors significantly contributed to performance quality but the cognitive factor did not significantly affect performance quantity and work attitudes. It is suggested that a combination of the 3 factors leads to the highest level of performance. (39 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献