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排序方式: 共有67条查询结果,搜索用时 31 毫秒
1.
A lot of researches are devoted to energy-save solutions in wireless sensor networks, to face their critical limited energy budget. In this paper we propose four information delivery mechanisms and we compare their relative energy impact, in order to make communications both reliable and energetic efficient. We present a parametric model to choose the best solution with respect to the great amount of factors that influence system performance, e.g., the hardware technology, the source to destination distance, the number of hops involved. For actual sensor nodes (/spl mu/AMPS-1) we are able to guarantee a whole delivery strategy with an energy gain ranging from 5% to 15% with respect to the trivial hop-to-hop decoding one. 相似文献
2.
Soisungwan Satarug David A. Vesey Muneko Nishijo Werawan Ruangyuttikarn Glenda C. Gobe Kenneth R. Phelps 《International journal of molecular sciences》2021,22(4)
Erroneous conclusions may result from normalization of urine cadmium and N-acetyl-β-D-glucosaminidase concentrations ([Cd]u and [NAG]u) to the urine creatinine concentration ([cr]u). In theory, the sources of these errors are nullified by normalization of excretion rates (ECd and ENAG) to creatinine clearance (Ccr). We hypothesized that this alternate approach would clarify the contribution of Cd-induced tubular injury to nephron loss. We studied 931 Thai subjects with a wide range of environmental Cd exposure. For x = Cd or NAG, Ex/Ecr and Ex/Ccr were calculated as [x]u/[cr]u and [x]u[cr]p/[cr]u, respectively. Glomerular filtration rate (GFR) was estimated according to the Chronic Kidney Disease (CKD) Epidemiology Collaboration (eGFR), and CKD was defined as eGFR < 60 mL/min/1.73m2. In multivariable logistic regression analyses, prevalence odds ratios (PORs) for CKD were higher for log(ECd/Ccr) and log(ENAG/Ccr) than for log(ECd/Ecr) and log(ENAG/Ecr). Doubling of ECd/Ccr and ENAG/Ccr increased POR by 132% and 168%; doubling of ECd/Ecr and ENAG/Ecr increased POR by 64% and 54%. As log(ECd/Ccr) rose, associations of eGFR with log(ECd/Ccr) and log(ENAG/Ccr) became stronger, while associations of eGFR with log(ECd/Ecr) and log(ENAG/Ecr) became insignificant. In univariate regressions of eGFR on each of these logarithmic variables, R2 was consistently higher with normalization to Ccr. Our tabular and graphic analyses uniformly indicate that normalization to Ccr clarified relationships of ECd and ENAG to eGFR. 相似文献
3.
Antonela Taddia María Julia Boggione Gisela Tubio 《International Journal of Food Science & Technology》2019,54(4):1027-1035
Agroindustrial by-products are an abundant source of biocompounds that contain valuable nutrients, which are not exploited. In this work, lignocellulosic wastes (LW) were used in submerged fermentation (SmF) and solid-state fermentation (SSF) by Aspergillus niger NRRL3 to obtain valuable enzymes required in industries. SmF using soya bean hulls (SH), wheat bran (WB) and a by-product of wheat flour (F) produced the highest activities of endo-1,4-β-xylanase (Xyl) and endo-1,4-β-D-glucanase (EG) being at least 3 times lower than those obtained by SSF. The highest ratio of Xyl to EG was obtained in SmF with F. Xyl obtained by SmF with WB was the most thermally resistant. The enzymatic extract obtained in SmF using SH presented a high power of saccharification. The production of enzymes for further application such as bioethanol generation process revalue these LW and can help offset growing environmental problems. 相似文献
4.
5.
Stefano Lo Russo Glenda Taddia Giorgia Baccino Vittorio Verda 《Energy and Buildings》2011,43(2-3):347-357
A multidisciplinary methodology is proposed for analyzing opportunities to use existing boreholes and an open-loop groundwater heat pump to provide summer cooling needs for large university buildings in Turin (NW Italy). The approach starts from a model of the buildings to determine the time profile of the cooling load. This curve is then coupled with a model of the off-design behaviour of the heat pump, which allows calculation of its energy performance (coefficient of performance, electricity consumption, etc.) as well as profiles of water discharge to the aquifer in terms of mass flow rate and temperature.Covering the peak energy needs of the buildings requires a variable amount of groundwater during the day. This could be provided varying the withdrawals from the aquifer but, as possible alternatives, two storage system solutions are examined: (1) chilled water storage and (2) groundwater storage. Simulations show that in both cases the use of storage systems produces environmental advantages, as the extent of the thermal plume reduces significantly. Moreover, chilled water storage presents a benefit in terms of reduced total primary energy consumption. The additional costs incurred by storage systems could necessitate public funding as well as system optimization. 相似文献
6.
Ainge James A.; Keating Glenda L.; Latimer Mary P.; Winn Philip 《Canadian Metallurgical Quarterly》2006,120(3):563
Pedunculopontine tegmental nucleus (PPTg) lesions in rodents lead to increased sucrose consumption, but the psychological deficit behind this remains uncertain. To understand better the relationship between consumption of, and motivation for, sucrose, the authors trained rats to traverse a runway for 20% or 4% sucrose solution; after 7 days, concentrations were reversed. Control rats consumed more 20% than 4% sucrose solution and promptly altered run times in response to concentration change. PPTg-lesioned rats consumed normal quantities of 4% but more 20% sucrose solution than controls and took longer to alter their runway time following the concentration change. These data suggest that lesions of the PPTg do not alter motivation per se and might be better understood as inducing a response selection deficit. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
7.
School psychologists commonly conduct interventions for individual students and evaluate their success through single-case research designs, most of which include a baseline observation period. However, concluding intervention effectiveness from a single-case design is problematic when pronounced baseline trend is evident. With positive baseline trend, interpretation of the measured mean difference between phases is ambiguous, and an invalid interpretation is probable. Although an adequate method for controlling baseline trend exists, it is rarely applied in published studies. This article seeks wider application of baseline trend control by describing a modified technique that blends more easily with visual analysis. A second goal of this article is to encourage better informed use of baseline trend control, by empirically demonstrating its need in published studies, and its impact on R2 effect sizes and on autocorrelation. Finally, baseline trend control is combined with elimination of autocorrelation, for results that can withstand the scrutiny of the broader research community. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
8.
Misbehavior by rats was produced in Exps I (16 Wistar female albino rats) and II (15 Sprague-Dawley female albino rats) by pairing a ball bearing with food or by requiring contact with the ball bearing for food (Exps IV, 6 Ss, and V, 11 Ss). Misbehavior occurred before and after eating the food pellet. The frequency, complexity, and duration of prepellet misbehavior was increased by delay of food until after the ball bearing exited (or was programmed to exit) and by requiring contact with the bearing to obtain food. Alternative goal-directed behaviors occurred in Pavlovian contingencies in which food was delivered before the bearing was programmed to exit. Postpellet misbehavior tended to occur when food was delivered before the bearing was programmed to exit and before S released the bearing. Omission of food delivery on contact reduced the duration, complexity, and frequency of misbehavior, although experienced Ss continued to contact (Exp III, 15 Ss). Misbehavior was affected by both stimulus- and response-reward contingencies but showed characteristic organization and topography under both types of contingency. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
T. K. Miwa F. R. Earle Glenda C. Miwa I. A. Wolff 《Journal of the American Oil Chemists' Society》1963,40(6):225-229
Quantitative measurements of epoxyoleic acid and co-occurring fatty acids in maturingVernonia anthelmintica (L.) Willd. seeds were made to elucidate partially the mode of epoxyoleic biosynthesis. Free (+)threo-12,13-dihydroxy-cis-9-octadecenoic acid was the major component at an intermediate maturation stage, and is believed to be dehydrated to free
epoxyoleic acid before incorporation into glycerides.
Presented before the Division of Biological Chemistry, Am. Chem. Soc. meeting in St. Louis, Mo., 1961.
A laboratory of the No. Utiliz. Res. & Dev. Div., ARS, U.S.D.A. 相似文献
10.
Three experiments studied the orienting behavior (OB) at 30, 60, 90, or 120 days old of male Long-Evans rats, of whom 88 were light-reared (LR) and 84 dark-reared (DR). OB was assessed by examining S's ability to interrupt ongoing licking and perform appropriate head and postural adjustments when presented with apparently moving or stationary light displays or tones. When the lights were first presented to the LR and DR Ss, their OB did not differ at any of the ages. However, age and visual experience did influence habituation and recovery of orienting with changes in the light display. The older DR Ss habituated with fewer repeated presentations of the light displays than the LR Ss and did not recover orienting as effectively to all the subsequent changes of the light displays. The younger LR and DR Ss did not differ reliably. Results are discussed with regard to the nature of the habituation process for rodents and the relation between visual experience and habituation of attentional responses. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献