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作者： Liu, Peng Yu, Jiyang Huang, Michael C. College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China State Key Laboratory of Mathematical Engineering and Advanced Computing Wuxi214125 China Department of Shannon Lab. Huawei Technologies Co. Ltd. Hangzhou310051 China Department of Electrical and Computer Engineering University of Rochester RochesterNY14627-0231 United States

Most processors employ hardware data prefetching techniques to hide memory access latencies. However, the prefetching requests from different threads on a multicore processor can cause severe interference with prefetching and/or demand requests of others. The data prefetching can lead to significant performance degradation due to shared resource contention on shared memory multicore systems. This article proposes a thread-aware data prefetching mechanism based on low-overhead runtime information to tune prefetching modes and aggressiveness, mitigating the resource contention in the memory system. Our solution has three new components: (1) a self-tuning prefetcher that uses runtime feedback to dynamically adjust data prefetching modes and arguments of each thread, (2) a filtering mechanism that informs the hardware about which prefetching request can cause shared data invalidation and should be discarded, and (3) a limiter thread acceleration mechanism to estimate and accelerate the critical thread which has the longest completion time in the parallel region of execution. On a set of multithreaded parallel benchmarks, our thread-aware data prefetchingmechanism improves the overall performance of 64-core system by 13% over a multimode prefetch baseline system with two-level cache organization and conventional modified, exclusive, shared, and invalid-based directory coherence *** compare our approach with the feedback directed prefetching technique and find that it provides 9% performance improvement on multicore systems, while saving the memory bandwidth consumption.

关键词： Benchmarking

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Iodine-catalyzed ammoxidation of methyl arenes

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CHEMICAL COMMUNICATIONS 2015年第24期51卷 5085-5088页

作者： Guo, Songjin Wan, Gen Sun, Song Jiang, Yan Yu, Jin-Tao Cheng, Jiang Changzhou Univ Sch Petrochem Engn Jiangsu Key Lab Adv Catalyt Mat & Technol Changzhou 213164 Peoples R China Changzhou Univ Jiangsu Prov Key Lab Fine Petrochem Engn Changzhou 213164 Peoples R China Nanjing Univ State Key Lab Coordinat Chem Nanjing 210093 Jiangsu Peoples R China

The development of organic transformation using cheap and readily available substrates under mild conditions will be pivotal for green and sustainable synthetic organic chemistry. Concerning our continued interest in the cyanation reaction, a metal-free direct ammoxidation of readily available methyl arenes leading to nitriles was established under mild conditions. A series of aryl methanes especially heteroaryl methanes (30 examples) were applicable in moderate to good yields with good functionality tolerance.

关键词： AROMATIC compounds RESEARCH IODINE CATALYSTS AMMOXIDATION METHYL groups CHEMICAL amplification

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Impact of Optical Hop Constraints on the IP/MPLS-over-WSON Networks CAPEX

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China Communications 2015年第11期12卷 112-118页

作者： LIU Fengqing Jaume Comellas School of Opto-Electronic Engineering Nanjing University of Posts and Telecommunications Dept.of Signal Theory and Communications Universitat Politècnica de Catalunya Barcelona

In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of networks varies significantly. This effect is thoroughly analyzed with a heuristic algorithm for different network topologies belonging to some European network operators. The main conclusion extracted is that limiting the transparent reach in such multi-layer networks can give a good tradeoff between CAPEX of IP/MPLS networks and WSON networks,and even lead to signifi cant savings in CAPEX when compared to longer lightpaths routing strategies.

关键词： IP/MPLS over WSON networks optical hop constraints CAPEX heuristics

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Preparation of ZIF-69 membranes for gasoline vapor recovery

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JOURNAL OF POROUS MATERIALS 2015年第5期22卷 1195-1203页

作者： Wu, Qigang Xu, Rong Li, Jing Zhang, Qi Zhong, Jing Huang, Weiqiu Gu, Xuehong Changzhou Univ Sch Petrochem Engn Jiangsu Key Lab Adv Catalyt Mat & Technol Changzhou 213164 Peoples R China Changzhou Univ Sch Petr Engn Changzhou 213016 Peoples R China Nanjing Univ Technol State Key Lab Mat Oriented Chem Engn Nanjing 210009 Jiangsu Peoples R China

The compact ZIF-69 membranes have been prepared by seeded growth method for the recovery of gasoline vapor which is a major challenge in the petrochemical industry. The membrane performances for separating N-2/n-alkane mixtures at various operating conditions (e.g. trans-membrane pressure difference, operating temperature, feed concentration, and stage cut) were systematically investigated. The highest separation factor was 2.60 with the corresponding permeance of 5.02 x 10(-8) mol/(m(2) s Pa) for the N-2/n-C6H14 model mixtures. Moreover, the effects of n-alkane components (n-C5H12, n-C6H14, and n-C7H16) on the separation performances were studied, and the separation factors followed alpha(N-2/n-C7H16) > alpha(N-2/n-C6H14) > alpha(N-2/n-C5H12), due to the different adsorption capacities of n-alkanes on ZIF-69 materials. The present work demonstrates that the ZIF-69 membrane is a highly promising candidate for the application in gasoline vapor recovery.

关键词： ZIF-69 membrane N-2/alkane (C5-C7) separation Gasoline vapor recovery Operating condition

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A highly efficient Pd/graphene oxide catalyst with abundant oxygen groups for the hydrogenation of olefins

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REACTION KINETICS MECHANISMS AND CATALYSIS 2015年第2期116卷 409-419页

作者： Liu, Ping Chang, Wan-Ting Wu, Meng-Yao Li, Yong-Xin Wang, Jun Changzhou Univ Inst Petrochem Technol Jiangsu Key Lab Adv Catalyt Mat & Technol Changzhou 213164 Jiangsu Peoples R China Nanjing Univ Technol Coll Chem & Chem Engn State Key Lab Mat Oriented Chem Engn Nanjing 210009 Peoples R China

A Pd/graphene oxide (Pd/GO) catalyst retaining abundant oxygen-containing groups was prepared by a facile and green method, and its physiochemical properties were characterized by inductively coupled plasma spectroscopy, Raman spectra, X-ray photoelectron spectroscopy, transmission electron microscopy and atomic force microscopy. Highly uniform Pd nanoparticles on GO sheets were found, along with well dispersion of the Pd/GO catalyst in ethanol. In the hydrogenation of olefins, Pd/GO exhibited much higher catalytic activities than those of the commercial Pd/C, and the counterpart Pd-supported on carbon nanotube and chemically reduced GO catalysts. An ultrahigh reaction rate of 45,447 mol (h mol(Pd))(-1) was obtained in the hydrogenation of styrene. The superior activity of the Pd/GO catalyst was largely attributed to the promoting effects of the abundant oxygen-containing groups on the sheets of GO.

关键词： Catalytic hydrogenation Graphene oxide Pd Olefin

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Highly dispersed Pd nanoparticles supported on nitrogen-doped graphene with enhanced hydrogenation activity

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RSC ADVANCES 2015年第89期5卷 72785-72792页

作者： Liu, Ping Li, Gen Chang, Wan-Ting Wu, Meng-Yao Li, Yong-Xin Wang, Jun Changzhou Univ Coll Chem & Chem Engn Jiangsu Key Lab Adv Catalyt Mat & Technol Changzhou 213164 Jiangsu Peoples R China Nanjing Univ Technol Coll Chem & Chem Engn State Key Lab Mat Oriented Chem Engn Nanjing 210009 Peoples R China

Pd nanoparticles supported on nitrogen-doped graphene (NG) were prepared as hydrogenation catalysts. Different nitrogen sources (ethylenediamine, ammonia, and urea) were employed to synthesize NG using hydrothermal treatment under mild conditions. The as-made samples were characterized by transmission electron microscopy, scanning electron microscopy, Raman spectroscopy, elemental analysis, nitrogen adsorption-desorption, X-ray diffraction, and X-ray photoelectron spectroscopy. Remarkably improved dispersion of Pd nanoparticles was observed when nitrogen was introduced into the graphene structure. These NG-supported Pd catalysts showed enhanced catalytic hydrogenation activities owing to the superior dispersion of Pd. In the hydrogenation of different olefins, perfect turnover frequencies were obtained over the NG-supported Pd catalyst with urea as the nitrogen source.

关键词： Urea

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Band alignment of atomic layer deposited high-k Al₂O₃/multilayer MoS₂ interface determined by X-ray photoelectron spectroscopy

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JOURNAL OF ALLOYS AND COMPOUNDS 2015年 650卷 502-507页

作者： Liu, Xinke He, Jiazhu Tang, Dan Liu, Qiang Wen, Jiao Yu, Wenjie Lu, Youming Zhu, Deliang Liu, Wenjun Cao, Peijiang Han, Sun Pan, Jisheng Liu, Wenjun Ang, Kah Wee He, Zhubing Shenzhen Univ Shenzhen Key Lab Special Funct Mat Shenzhen Engn Lab Adv Technol Ceram Coll Mat Sci & Engn Shenzhen 518060 Peoples R China Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol State Key Lab Funct Mat Informat Shanghai 200050 Peoples R China Agcy Sci Technol & Res Inst Mat Res & Engn Singapore 117602 Singapore Fudan Univ Dept Microelect Shanghai 200433 Peoples R China Natl Univ Singapore Dept Elect & Comp Engn Singapore 117583 Singapore South Univ Sci & Technol China Dept Mat Sci & Engn Shenzhen 518055 Peoples R China

The energy band alignment between Al2O3/multilayer (ML)-MoS2 was characterized using high-resolution x-ray photoelectron spectroscopy (XPS). The Al2O3 was deposited using an atomic layer deposition (ALD) tool. A valence band offset of 4.10 eV and a conduction band offset of 3.41 eV were obtained across the ALD-Al2O3/ML-MoS2 interface. For comparison, the valence band offset and a conduction band offset were also obtained for ALD-SiO2/ML-MoS2 interface. It was found out that ALD-Al2O3/ML-MoS2 interface has a larger conduction band offset, compared to that of ALD-SiO2/ML-MoS2 interface, which indicate ALD-Al2O3 served as the gate dielectric for n-type ML-MoS2 based field effect transistors has advantage over ALD-SiO2 in term of suppressing the gate leakage current. (C) 2015 Elsevier B.V. All rights reserved.

关键词： Multilayer MoS2 High-k Band alignment X-ray photoelectron spectroscopy

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Suppressing low-frequency components of common-mode voltage through reverse injection in three-phase inverter

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IET POWER ELECTRONICS 2014年第6期7卷 1644-1653页

作者： Huang, Jin Shi, Haixia Huazhong Univ Sci & Technol Sch Elect & Elect Engn Wuhan 430074 Peoples R China Wuhan Text Univ Sch Foreign Languages Wuhan Peoples R China

The output common-mode voltage (CMV) will bring many negative effects in a three-phase inverter, which is controlled by the sinusoidal pulse-width modulation (SPWM) method. The carrier phase-shift method and the carrier-frequency modulation method can reduce the peaks of the CMV at the switching frequency and its harmonic frequencies, but they may cause increase of the low-frequency (LF) baseband harmonics. A new reverse injection scheme is proposed to suppress the LF harmonics. In this scheme, the parameters of the interference peaks are obtained through CMV detection and real-time harmonic parameters estimation. The estimated phase errors from the detection-control delay are amended by the method of temporary addition of the standard phase signal. Then, the sinusoids with a reverse phase to the LF harmonics are generated and injected in the reference sinusoid of each phase to produce the SPWM. Thus, the LF peaks of the CMV are counteracted. The feasibility and the validity of this scheme are verified through the experiments under different control strategies.

关键词： modulation mode sinusoidal pulse width modulation peaks phase signal three-phase inverter Parameter estimation low frequencies phase inverter common mode voltage Cytomegalovirus

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Optimal Kalman Filtering in the Presence of Time-Correlated Process Noise 6th

Optimal Kalman Filtering in the Presence of Time-Correlated ...

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China Satellite Navigation Conference (CSNC) 2015 Proceedings, VolII

作者： Zhou, Zebo Wu, Yunlong Chai, Hua Univ Elect Sci & Technol China Sch Aeronaut & Astronaut Chengdu 611731 Peoples R China China Earthquake Adm Inst Seismol Key Lab Earthquake Geodesy Wuhan 430071 Peoples R China Chinese Acad Sci Inst Geodesy & Geophys Wuhan 430077 Peoples R China

ISBN: (纸本)9783662466353;9783662466346

Kalman filtering ( KF), in previous works, assumes that system noises are white Gaussian noises ( WGN) and are uncorrelated with each other. This assumption, however, is not reasonable in real-world navigation applications. This paper dedicates to develop an optimal Kaman filtering navigation algorithm in the time-correlated contained dynamic system. Efforts are made on its stochastic model establishment and the corresponding recursive formulae derivations. First, as a popular sort of time-correlated noise-whitening method, the principle of state augmentation based KF ( SAKF) is reviewed and presented. Alternative method second moment information based KF ( SMIKF) which directly compensates the variances through stochastic model is proposed and developed. To precisely establish the stochastic model of time-correlated process noise, a refined SMIKF ( RSMIKF) is further rigorously proposed and derived from continuous-time dynamic model. We also investigate the numerical computation burden for these developed methods compared with conventional KF ( CKF). Finally, a simulation experiment is carried out to illustrate the performances of our proposed algorithm. The accuracies of CKF and our proposed methods are all computed and analyzed for comparison purpose. The results show that the proposed RSMIKF algorithm adapts to the time-correlated process noise very well and obtains the accurate and reliable solutions compared with other methods as expected.

关键词： Time-correlated noise Kalman filtering Dynamic model Autoregressive model Stochastic model

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Upconversion Luminescence Properties of Phase and Size Controlled NaLnF₄:Yb³⁺, Er³⁺(Ln = Y, Gd) Nanoparticles

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JOURNAL OF NANOSCIENCE AND NANOtechnology 2015年第1期15卷 368-372页

作者： Hu, Rongxuan Ye, Song Wang, Huiyun Zhang, Wenjun Zhang, Zhiyuan Lin, Jian Wang, Deping Tongji Univ Sch Mat Sci & Engn Shanghai 201806 Peoples R China Tongji Univ Sch Phys Sci & Engn Shanghai 201806 Peoples R China

The upconversion luminescent nanoparticles of NaLnF(4) (Ln = Y, Gd):Yb3+, Er3+ were prepared through a facile modified solvothermal method, in which the phase (cubic or hexagonal) and size of the NaLnF(4) nanoparticles can be well controlled by adjusting Gd3+ content. The Gd3+ content dependent phase transformation and size change were systematically studied by the XRD and TEM measurements. The spectral measurement revealed that both the emission intensity and the intensity ratio of red (F-4(9/2) -> I-4(15/2)) to green (H-2(11/2), S-4(3/2) -> I-4(15/2)) are tunable, and a significant increase of the visible upconversion emission intensity can be realized by optimizing Gd3+ content at x = 0.25 under 980 nm excitation. Furthermore, the excitation power dependent red and green emission intensities of Er3+ were measured for various NaLnF(4) (Ln = Y, Gd):Yb3+, Er3+ nanoparticles with different Gd3+ content to investigate the influence of the phase and particle size on the upconversion luminescence properties. This research provided a new method to synthesize the upconversion nanoparticles with tunable luminescence properties by adjusting Gd3+ content.

关键词： Tunable Upconversion Luminescence NaLnF(4) (Ln = Y, Gd) Rare Earth Ions

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