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101.
Onur Altintas Toshihiko Watanabe Haris Kremo Hideaki Tanaka Hitoshi Nakao Kazuya Tsukamoto Masato Tsuru 《Journal of Signal Processing Systems》2016,85(1):45-66
In the past years, many works have demonstrated the applicability of Coarse-Grained Reconfigurable Array (CGRA) accelerators to optimize loops by using software pipelining approaches. They are proven to be effective in reducing the total execution time of multimedia and signal processing applications. However, the run-time reconfigurability of CGRAs is hampered overheads introduced by the needed translation and mapping steps. In this work, we present a novel run-time translation technique for the modulo scheduling approach that can convert binary code on-the-fly to run on a CGRA. We propose a greedy approach, since the modulo scheduling for CGRA is an NP-complete problem. In addition to read-after-write dependencies, the dynamic modulo scheduling faces new challenges, such as register insertion to solve recurrence dependences and to balance the pipelining paths. Our results demonstrate that the greedy run-time algorithm can reach a near-optimal ILP rate, better than an off-line compiler approach for a 16-issue VLIW processor. The proposed mechanism ensures software compatibility as it supports different source ISAs. As proof of concept of scaling, a change in the memory bandwidth has been evaluated. In this analysis it is demonstrated that when changing from one memory access per cycle to two memory accesses per cycle, the modulo scheduling algorithm is able to exploit this increase in memory bandwidth and enhance performance accordingly. Additionally, to measure area and performance, the proposed CGRA was prototyped on an FPGA. The area comparisons show that a crossbar CGRA (with 16 processing elements and including an 4-issue VLIW host processor) is only 1.11 × bigger than a standalone 8-issue VLIW softcore processor. 相似文献
102.
Zeynep Mutlu Mayank Jain Sung Ho Yook Mukerrem Cakmak 《Journal of polymer science. Part A, Polymer chemistry》2021,59(18):2045-2056
Mechano-optical behavior and related structural evolution during uniaxial stretching of melt miscible poly (ethylene terephthalate) (PET)/poly (ether imide) (PEI) blends were studied near their glass transition temperature using an instrumented machine that measures true stress, true strain and spectral birefringence simultaneously. Stretching from amorphous state, two distinct stress-optical regimes were observed at temperatures between Tg and Tcc (cold crystallization). Near Tg, a typical photoelastic behavior persists until a critical temperature above which temperature independent initial stress optical behavior is observed. At those temperatures above Tg, where glassy behavior is observed, decreasing stretching rate was also found to eliminate this glassy photo elastic regime leading to the observation of a linear initial stress optical behavior that becomes temperature independent as expected from linear stress optical rule. Increasing PEI concentration in the blends suppresses crystallizability and increases temperature at which initial elastic region disappears giving way to pure liquid behavior where linear stress optical behavior is observed. This is attributed to the increase and broadening of the glass transition temperature with the addition of noncrystallizable PEI. In PET/PEI blends, the stress-optical coefficient (SOC), determined in a linear stress optical regime, was found to increase linearly with the increase in PEI concentration. 相似文献
103.
We overview the challenges related to spectrum awareness in the vehicular environment, with emphasis on awareness in the TV licensed band. In the vehicular environment the cognitive radio can help to: 1) satisfy capacity demand for Intelligent Transportation Systems (ITS) applications; and 2) offload time insensitive applications from the ITS dedicated spectrum. However, using simple propagation models we show that neither sensing, nor geolocation database lookup alone can provide sufficient incumbent protection. Collaboration among the sensors to take advantage of spatial diversity is difficult due to the rapidly changing network topology. Nevertheless, mobility provides the opportunity to use time diversity at each sensor. We also discuss the influence of sensing subsystem design on the vehicular cognitive network medium access (MAC) sublayer. Whenever appropriate, we evaluate applicability of the requirements imposed by the Federal Communications Commission (FCC) and the IEEE 802.22 standard to the cognitive vehicular networks. 相似文献
104.
JPC – Journal of Planar Chromatography – Modern TLC - α-Cypermethrin is a synthetic pyrethroid insecticide used to control insects. In soil, α-cypermethrin biodegrades... 相似文献
105.
Ozcan Altintas Tobias Rudolph Christopher Barner‐Kowollik 《Journal of polymer science. Part A, Polymer chemistry》2011,49(12):2566-2576
Well‐defined heterotelechelic poly(styrene) carrying thymine/diaminopyridine (DAP) (Mn,SEC = 9300, PDI = 1.04) and Hamilton wedge (HW)/cyanuric acid (CA) (Mn,SEC = 8200, PDI = 1.04) bonding motifs are prepared via a combination of controlled/living radical polymerization and copper catalyzed azide/alkyne “click” chemistry and are subsequently self‐assembled as single chains to emulate—on a simple level—the self‐folding behavior of natural biomacromolecules. Hydrogen nuclear magnetic resonance (1H NMR) in deuterated dichloromethane and dynamic light scattering analyses provides evidence for the hydrogen bonding interactions between the α‐thymine and ω‐DAP as well as α‐CA and ω‐HW chain ends of the heterotelechelic polymers leading to circular entropy driven single chain self‐assembly. This study demonstrates that the choice of NMR solvent is important for obtaining well‐resolved NMR spectra of the self‐assembled structures. In addition, steric effects on the HW can affect the efficiency of the self‐assembly process. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
106.
Zeynep anl Tuncay Krolu Bahadr
zgür Güler 《Mathematical Methods in the Applied Sciences》2019,42(16):5403-5415
In this paper, the normalizers of , for k = 2 or 3, in the groups Γk of modular group Γ are given by using the concept of Γk axes of the set of left cosets of , on which Γk acts transitively, in Γk. 相似文献
107.
Akgun Z Engelbrecht H Fan KH Barnes CL Cutler CS Jurisson SS Lever SZ 《Dalton transactions (Cambridge, England : 2003)》2010,39(42):10169-10178
(103)Rhodium(III) complexes derived from seven acyclic tetradentate N(2)S(2) ligands (one diaminedithiol and six diaminedithioether ligands) have been synthesized and characterized. Structural variations in the ligand include the length of carbon backbone between the coordinating atoms (222; 232; 323; 333), the presence or absence of gem-dimethyl groups α to sulfur, and the nature of the organic moiety on the sulfurs (hydrogen, p-methoxybenzyl and methyl). For each ligand, the formation of cis and/or trans dichloro isomeric complexes was assessed. Two complexes have been further characterized by single crystal X-ray diffraction. Preparation of the (103)Rhodium(III) complexes was conducted and overall radiochemical yields, in vitro stability and log D(7.4) values were measured. From these studies, the ligand with the 232 chain length, gem-dimethyl groups and the methyl thioether (L4) emerged as a preferred ligand for formation of rhodium complexes with trans geometry and highest radiochemical yields. 相似文献
108.
A simple and sensitive method has been developed and validated for the determination of aliskiren (ALS) in its dosage forms
and spiked plasma. The method was based on the reaction of the drug with dansyl chloride in the presence of bicarbonate solution
of pH 10.5 to give a highly fluorescent derivative which was measured at 501 nm with excitition at 378 nm in dichloromethane.
Different experimental parameters affecting the development of the method and stability were carefully studied and optimized.
The calibration curves were linear over the concentration ranges of 100–700 and 50–150 ng/mL for standard solution and plasma,
respectively. The limits of detection were 27.52 ng/mL in standard solution, 4.91 ng/mL in plasma. The developed method was
successfully applied to the analysis the drug in the commercial tablets and spiked plasma samples. The mean recovery of ALS
from tablets and plasma was 100.10 and 97.81%, respectively. A proposal of the reaction pathway was presented. 相似文献
109.
F. Zeynep SargutLian Qi 《Operations Research Letters》2012,40(2):114-122
We study a continuous-review inventory problem of a two-echelon supply chain with random disruptions, identify properties of the optimal cost function, compare the optimal order quantity with the classical economic order quantity, analyze the sensitivity of the optimal solution, and explore the conditions under which zero-inventory ordering policy is preferred. 相似文献
110.
A new phenolic ester 2-( p-hydroxyphenyl)ethyl eicosaheptanoic acid ester (1) and a known one hexacosylferulate (2) were isolated from the acetone extract of Salvia microphylla. In addition, two sesquiterpenes beta-eudesmol (3) and 8alpha-hydroxy-beta-eudesmol (4), a diterpene carnosic acid 12-methyl ether (12-methoxycarnosic acid) (5), three triterpenes erithrodiol 3-acetate, oleanolic acid, lupeol and beta-sitosterol were obtained as known compounds from this plant extract. The structures of the isolated compounds were elucidated by spectroscopic methods, including one- and two- dimensional 1H- and 13C-NMR and MS spectroscopies. The selected compounds were tested for antimicrobial activity against standard bacterial strains, and only carnosic acid 12-methyl ether showed antimicrobial activity against S. aureus at 78 microg mL(-1). 相似文献