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41.
实时多处理器系统中基于能量节约的动态调度算法 总被引:1,自引:0,他引:1
当前处理器由于较高的能量消耗。导致处理器热量散发的提高及系统可靠性的降低,已经成为目前计算机领域较为关心的问题.然而目前一些有效降低能量消耗的技术大多针对单处理器系统,较少考虑多处理器系统.本文提出的调度算法针对多处理器系统,以最短任务优先调度为基础,结合其它有效技术,如共享空闲时间回收等,使得实时任务在其截止期内完成的同时能够有效地减低整个系统的能量消耗.针对独立任务集及具有依赖关系的任务集,本文提出两种算法:STFBA1及STFBA2(Shortest Task First—Based Algorithm).与目前所知的有效算法相比,我们的算法具有更好的性能(调度长度及能量消耗). 相似文献
42.
Amro A. El-Baz M. Kamal T. Ewida M. Abbas Shouman Mahmoud M. El-Halwagi 《Clean Technologies and Environmental Policy》2005,7(2):78-86
The objective of this paper is to develop a systematic methodology for mass integration in drain systems and watersheds. Mass integration is a holistic approach to the tracking, transformation, and allocation of species and streams. The watershed and drain system is first discretized into reaches. The MFA model developed in part I of this work (Simulation and Application to Ammonium Management in Bahr El-Baqar Drain System) is used to describe the environmental phenomena that affect the fate and transport of targeted species and the operators that characterize the system inputs and outputs as they relate to the surroundings. Next, we develop an integration framework which encompasses sources, sinks, and interception technologies to aid in the development for nitrogen-management strategies. The simulation model was transformed into a synthesis model by introducing optimization variables and including models for the potential management strategies. The problem of minimizing negative environmental impact subject to technical, social, economic, and regulatory constraints was posed as a nonlinear optimization program whose solution identified and synthesized the most effective solution strategies. These mathematical models and management strategies were coded into a computer-aided tool using LINGO programming platform. The program can be readily modified to address a variety of cases. Tradeoffs and sensitivity analysis were established using the devised model. The devised framework was applied to an Egyptian drain system (Bahr El-Baqar) along with the outfall to Lake Manzala. The results of the case study provide solution strategies for nitrogen management along with their technical, economic, and environmental implications. 相似文献
43.
The present study presents a methodology for detailed reliability analysis of nuclear containment without metallic liners against aircraft crash. For this purpose, a nonlinear limit state function has been derived using violation of tolerable crack width as failure criterion. This criterion has been considered as failure criterion because radioactive radiations may come out if size of crack becomes more than the tolerable crack width. The derived limit state uses the response of containment that has been obtained from a detailed dynamic analysis of nuclear containment under an impact of a large size Boeing jet aircraft. Using this response in conjunction with limit state function, the reliabilities and probabilities of failures are obtained at a number of vulnerable locations employing an efficient first-order reliability method (FORM). These values of reliability and probability of failure at various vulnerable locations are then used for the estimation of conditional and annual reliabilities of nuclear containment as a function of its location from the airport. To study the influence of the various random variables on containment reliability the sensitivity analysis has been performed. Some parametric studies have also been included to obtain the results of field and academic interest. 相似文献
44.
45.
实时任务在实际应用中通常需要以独占方式访问共享资源, 但是由于资源的独占性导致高优先权任务运行时往往被低优先权任务阻塞, 从而产生优先权反转, 难以满足任务的实时性;同时当前处理器由于较高的能量消耗,导致处理器热量散发提高及系统可靠性降低, 已经成为目前计算机领域较为关心的问题.提出一种基于任务同步及节能的实时调度算法CSSFA,有效地解决了上述难题.CSSFA在满足任务实时可调度性及任务同步的条件下,固定临界区的运行速度,使更多的空闲时间用于非临界区部分,有效地降低了整体系统的能耗;同时也能避免高优先权任务被阻塞、临界区继承高优先权任务的速度时所造成的处理器电压开关的频繁切换, 因而能有效地降低实时任务调度的成本.试验测试表明,CSSFA在调度性能上明显优于目前所知的有效算法. 相似文献
46.
N6-methyladenine (6mA) has been recognized as a key epigenetic alteration that affects a variety of biological activities. Precise prediction of 6mA modification sites is essential for understanding the logical consistency of biological activity. There are various experimental methods for identifying 6mA modification sites, but in silico prediction has emerged as a potential option due to the very high cost and labor-intensive nature of experimental procedures. Taking this into consideration, developing an efficient and accurate model for identifying N6-methyladenine is one of the top objectives in the field of bioinformatics. Therefore, we have created an in silico model for the classification of 6mA modifications in plant genomes. ENet-6mA uses three encoding methods, including one-hot, nucleotide chemical properties (NCP), and electron–ion interaction potential (EIIP), which are concatenated and fed as input to ElasticNet for feature reduction, and then the optimized features are given directly to the neural network to get classified. We used a benchmark dataset of rice for five-fold cross-validation testing and three other datasets from plant genomes for cross-species testing purposes. The results show that the model can predict the N6-methyladenine sites very well, even cross-species. Additionally, we separated the datasets into different ratios and calculated the performance using the area under the precision–recall curve (AUPRC), achieving 0.81, 0.79, and 0.50 with 1:10 (positive:negative) samples for F. vesca, R. chinensis, and A. thaliana, respectively. 相似文献
47.
Microencapsulation of Oils: A Comprehensive Review of Benefits,Techniques, and Applications 总被引:1,自引:0,他引:1 下载免费PDF全文
Amr M. Bakry Shabbar Abbas Barkat Ali Hamid Majeed Mohamed Y. Abouelwafa Ahmed Mousa Li Liang 《Comprehensive Reviews in Food Science and Food Safety》2016,15(1):143-182
Microencapsulation is a process of building a functional barrier between the core and wall material to avoid chemical and physical reactions and to maintain the biological, functional, and physicochemical properties of core materials. Microencapsulation of marine, vegetable, and essential oils has been conducted and commercialized by employing different methods including emulsification, spray‐drying, coaxial electrospray system, freeze‐drying, coacervation, in situ polymerization, melt‐extrusion, supercritical fluid technology, and fluidized‐bed‐coating. Spray‐drying and coacervation are the most commonly used techniques for the microencapsulation of oils. The choice of an appropriate microencapsulation technique and wall material depends upon the end use of the product and the processing conditions involved. Microencapsulation has the ability to enhance the oxidative stability, thermostability, shelf‐life, and biological activity of oils. In addition, it can also be helpful in controlling the volatility and release properties of essential oils. Microencapsulated marine, vegetable, and essential oils have found broad applications in various fields. This review describes the recognized benefits and functional properties of various oils, microencapsulation techniques, and application of encapsulated oils in various food, pharmaceutical, and even textile products. Moreover, this review may provide information to researchers working in the field of food, pharmacy, agronomy, engineering, and nutrition who are interested in microencapsulation of oils. 相似文献
48.
Nadeem Abbas Faisal Abdullah Ijaz Hussain Muhammad Ikram Shazia Anwer Bukhari 《International Journal of Food Properties》2017,20(11):2782-2792
The objective of the present study was to analyze and compare the phenolic compounds and their antioxidant capacities of new lines of Dacus carota. The selected cultivars showed high variation in the contents of total phenolics (30.26–65.39 mg/100 g FW) and total ascorbic acid (41.12–58.36 mg/100 g FW). Analysis on RP-HPLC revealed that hydroxycinnamic acids and its derivatives were major phenolic compounds present in D. carota extracts, whereas 5-caffeolquinic acid was a major hydroxycinnamic acid (ranged from 30.26 to 65.39 mg/100 g FW). DCP cultivar showed high total antioxidant capacity (77.69 mg/100 g), 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity (52.36 mg/100 g), superoxide radical scavenging capacity (53.69 mg/100 g), and hydroxyl radical scavenging capacity (51.91 mg/100 g). A linear relationship was found between total phenolic acid contents and antioxidant capacity. Both phenolic compounds and antioxidant capacities varied significantly (ρ < 0.05) among cultivars. DCP cultivar was found to be a rich source of phenolics and ascorbic acid with high antioxidant activity. 相似文献
49.
Abdul Qadir Shah Tasneem Gul Kazi Muhammad Balal Arain Muhammad Khan Jamali Hassan Imran Afridi Nusrat Jalbani Ghulam Abbas kandhro Jameel Ahmed Baig Raja Adil sarfraz Rehana ansari 《Food chemistry》2009
The purpose of this study was to estimate total arsenic concentration in different tissues (leg, breast, liver and heart) of broiler chicken by hydride generation atomic absorption spectrometry (HGAAS) and graphite furnace atomic absorption spectrometry (GFAAS), prior to microwave assisted acid digestion. The accuracy of the techniques was evaluated by using certified reference material DORM-2. The percentage recoveries of total As were observed as 100.6% and 99.4% for HGAAS and GFAAS, respectively. The precision of the techniques, expressed as relative standard deviation, was observed as 1.71% and 4.18% for HGAAS and GFAAS measurements, respectively. The limits of detection for HGAAS and GFAAS were 0.025 μg/g and 0.052 μg/g, respectively. The concentrations of total arsenic in different tissues of broiler chicken were found in the range of 2.19–5.28, 2.15–5.22, 2.97–7.17 and 2.68–6.36 μg/g for leg, breast, liver and heart tissues, respectively. At a mean level of chicken consumption (60 g/person/day), people may ingest in the range of 72.0–85.1 μg arsenic/person/day from chicken alone. 相似文献
50.
M. Abbas Ali Ayesha Nargis Noor Hidayu Othman Ahmadil Fitri Noor Golam Sadik Jewel Hossen 《International Journal of Food Properties》2017,20(11):2569-2580
The oxidative stability and compositional characteristics of the pumpkin seed oil (PSO) exposed to microwaves were studied during heating at 170°C. The oxidative indices such as free fatty acid (FFA), peroxide value (PV), p-anisidine value (p-AV), TOTOX, specific extinctions and thiobarbituric acid (TBA) value of oils were significantly increased, and the increments were found to be significantly higher (P < 0.05) in unroasted seed oil as compared to roasted seed oil. The relative contents of polyunsaturated fatty acids (PUFAs) were decreased to 84.7%, and saturated fatty acids (SFAs) were increased to 119.5% in unroasted sample, after 9 h of heating. On the other hand, in 12 min roasted samples, the relative contents of PUFAs were decreased to 97.0%, and SFAs were increased to 102.6% after 9 h of heating. The triacylglycerol species LLL and OLL levels were decreased as a consequence of increased heating time, and the reduction tended to be significantly higher in unroasted samples as compared to roasted ones. The oxidation products formed were also investigated by FTIR. The present results indicated that microwave roasting of pumpkin seeds markedly enhanced the oxidative stability of the oils during heating. 相似文献