Software Pipeline–Based Partitioning Method with Trade-Off between Workload Balance and Communication Optimization

Kai Huang,Min Yu,Xiaomeng Zhang,Rongjie Yan,Xiaolang Yan,Zhili Liu,Siwen Xiu 한국전자통신연구원 2015 ETRI Journal Vol.37 No.3

For a multiprocessor System-on-Chip (MPSoC) to achieve high performance via parallelism, we must consider how to partition a given application into different components and map the components onto multiple processors. In this paper, we propose a software pipeline–based partitioning method with cyclic dependent task management and communication optimization. During task partitioning, simultaneously considering computation load balance and communication optimization can cause interference, which leads to performance loss. To address this issue, we formulate their constraints and apply an integer linear programming approach to find an optimal partitioning result — one that requires a trade-off between these two factors. Experimental results on a reconfigurable MPSoC platform demonstrate the effectiveness of the proposed method, with 20% to 40% performance improvements compared to a traditional software pipeline–based partitioning method.

Effect of Various Retrogression Regimes on Aging Behavior and Precipitates Characterization of a High Zn-Containing Al–Zn–Mg–Cu Alloy

Kai Wen,Baiqing Xiong,Yongan Zhang,Zhihui Li,Xiwu Li,Shuhui Huang,Lizhen Yan,Hongwei Yan,Hongwei Liu 대한금속·재료학회 2018 METALS AND MATERIALS International Vol.24 No.3

In the present work, the infl uence of various retrogression treatments on hardness, electrical conductivity and mechanicalproperties of a high Zn-containing Al–Zn–Mg–Cu alloy is investigated and several retrogression regimes subjected to a samestrength level are proposed. The precipitates are qualitatively investigated by means of transmission electron microscopy(TEM) and high-resolution transmission electron microscopy techniques. Based on the matrix precipitate observations, thedistributions of precipitate size and nearest inter-precipitate distance are extracted from bright-fi eld TEM images projectedalong ⟨110⟩ Al orientation with the aid of an imaging analysis and an arithmetic method. The results show that GP zonesand η′ precipitates are the major precipitates and the precipitate size and its distribution range continuously enlarge with theretrogression regime expands to an extent of high temperature. The nearest inter-precipitate distance ranges obtained arequite the same and the average distance of nearest inter-precipitates show a slight increase. The infl uence of precipitates onmechanical properties is discussed through the interaction relationship between precipitates and dislocations.

Ultrathin Two-Dimensional Atomic Crystals as Stable Interfacial Layer for Improvement of Lithium Metal Anode

Yan, Kai,Lee, Hyun-Wook,Gao, Teng,Zheng, Guangyuan,Yao, Hongbin,Wang, Haotian,Lu, Zhenda,Zhou, Yu,Liang, Zheng,Liu, Zhongfan,Chu, Steven,Cui, Yi American Chemical Society 2014 NANO LETTERS Vol.14 No.10

<P>Stable cycling of lithium metal anode is challenging due to the dendritic lithium formation and high chemical reactivity of lithium with electrolyte and nearly all the materials. Here, we demonstrate a promising novel electrode design by growing two-dimensional (2D) atomic crystal layers including hexagonal boron nitride (h-BN) and graphene directly on Cu metal current collectors. Lithium ions were able to penetrate through the point and line defects of the 2D layers during the electrochemical deposition, leading to sandwiched lithium metal between ultrathin 2D layers and Cu. The 2D layers afford an excellent interfacial protection of Li metal due to their remarkable chemical stability as well as mechanical strength and flexibility, resulting from the strong intralayer bonds and ultrathin thickness. Smooth Li metal deposition without dendritic and mossy Li formation was realized. We showed stable cycling over 50 cycles with Coulombic efficiency ∼97% in organic carbonate electrolyte with current density and areal capacity up to the practical value of 2.0 mA/cm<SUP>2</SUP>and 5.0 mAh/cm<SUP>2</SUP>, respectively, which is a significant improvement over the unprotected electrodes in the same electrolyte.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2014/nalefd.2014.14.issue-10/nl503125u/production/images/medium/nl-2014-03125u_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl503125u'>ACS Electronic Supporting Info</A></P>

Electrophysiological and alarm behavioral responses of Solenopsis invicta Buren (Hymenoptera: Formicidae) to alkoxypyrazines

Yan Sun,Kai-Min Shao,Yongyue Lu,Qun-Hui Shi,Wen-Kai Wang,Li Chen 한국응용곤충학회 2017 Journal of Asia-Pacific Entomology Vol.20 No.2

The red imported fire ant, Solenopsis invicta produces an alarm pheromone component, 2-ethyl-3,6- dimethylpyrazine, and responds to its pyrazine analogs in a similar manner but at varied detection thresholds. Herein, the responses of fire ant workers by electroantennogram (EAG) and behavior were tested with twelve structurally-related oxygen-containing pyrazines (alkoxypyrazines) and the synthetic alarm pheromone. All tested compounds elicited a dose-dependent EAG response, with S. invicta responding greatest to the synthetic alarmpheromone. Chemical structure of pyrazines influenced the EAG response but not always alarmbehavioral response. Among the 13 tested compounds, 7 compounds displayed significantly greater EAG response than 2- isopropyl-3-methoxypyrazine and 2-ethoxy-3-isopropylpyrazine at the dose of 1000 μg. Four of these 7 compounds, 2-ethyl-3,6-dimethylpyrazine, 2-methoxy-3-methylpyrazine, 2-ethoxy-3(5 or 6)-methylpyrazine, and 2-chloro-3-methoxypyrazinewith characteristic substituents on pyrazine ringwere further subjected to bait discovery bioassay.Hotdog bait containing pyrazines attracted significantlymore fire antworkers in the first 15-min period, resulting in quicker recruitment to food block than hexane control. The potential of using alkoxypyrazines in fire ant control is discussed.

Vibrational characteristic of FG porous conical shells using Donnell’s shell theory

Kai Yan,Yao Zhang,Hao Cai,Vahid Tahouneh 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.35 No.2

The main purpose of this research work is to investigate the free vibration of conical shell structures reinforced by graphene platelets (GPLs) and the elastic properties of the nanocomposite are obtained by employing Halpin-Tsai micromechanics model. To this end, a shell model is developed based on Donnell’s theory. To solve the problem, the analytical Galerkin method is employed together with beam mode shapes as weighting functions. Due to importance of boundary conditions upon mechanical behavior of nanostructures, the analysis is carried out for different boundary conditions. The effects of boundary conditions, semi vertex angle, porosity distribution and graphene platelets on the response of conical shell structures are explored. The correctness of the obtained results is checked via comparing with existing data in the literature and good agreement is eventuated. The effectiveness and the accuracy of the present approach have been demonstrated and it is shown that the Donnell’s shell theory is efficient, robust and accurate in terms of nanocomposite problems.

Heteroatoms in situ-doped hierarchical porous hollow-activated carbons for high-performance supercapacitor

Yan Rui,Wang Kai,Tian Xiaodong,Li Xiao,Yang Tao,Xu Xiaotong,He Yiting,Lei Shiwen,Song Yan 한국탄소학회 2020 Carbon Letters Vol.30 No.3

Heteroatoms in situ-doped hierarchical porous hollow-activated carbons (HPHACs) have been prepared innovatively by pyrolyzation of setaria viridis combined with alkaline activation for the frst time. The micro-morphology, pore structure, chemical compositions, and electrochemical properties are researched in detail. The obtained HPHACs are served as outstand�ing electrode materials in electrochemical energy storage ascribe to the particular hierarchical porous and hollow structure, and the precursor setaria viridis is advantage of eco-friendly as well as cost-efective. Electrochemical measurement results of the HPHACs electrodes exhibit not only high specifc capacitance of 350 F g−1 at 0.2 A g−1, and impressive surface specifc capacitance (Cs) of 49.9 μF cm−2, but also substantial rate capability of 68% retention (238 F g−1 at 10 A g−1) and good cycle stability with 99% retention over 5000 cycles at 5 A g−1 in 6 M KOH. Besides, the symmetrical supercapacitor device based on the HPHACs electrodes exhibits excellent energy density of 49.5 Wh kg−1 at power density of 175 W kg−1 , but still maintains favorable energy density of 32.0 Wh kg−1 at current density of 1 A g−1 in 1-ethy-3-methylimidazolium tetrafuoroborate (EMIMBF4) ionic liquid electrolyte, and the excellent cycle stability behaviour shows the nearly 97% ratio capacitance retention of the initial capacitance after 10,000 cycles at current density of 2 A g−1. Overall, the results indicate that HPHACs derived from setaria viridis have appealing electrochemical performances thus are promising electrode materi�als for supercapacitor devices and large-scale applications.

Measurement and Theoretical Calculation Confirm the Improvement of T7651 Aging State Influenced Precipitation Characteristics on Fatigue Crack Propagation Resistance in an Al–Zn–Mg–Cu Alloy

Kai Wen,Baiqing Xiong,Yongan Zhang,Zhihui Li,Xiwu Li,Lizhen Yan,Hongwei Yan,Hongwei Liu 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

Precipitation characteristics influencing fatigue crack propagation contained matrix precipitate, grain boundary precipitateand precipitate free zone for Al–Zn–Mg–Cu alloys. Over-aging treatment could effectively regulate precipitation and then tobe able to change fatigue crack propagation behavior compared with the peak aging state. In the current work, typical T651and T7651 aging tempers of the alloy were extracted via hardness, electrical conductivity and mechanical properties underone-step and two-step aging treatments. Fatigue crack propagation (FCP) rate under them was tested and correspondingprecipitation characteristics and fracture morphology were observed. The results indicated that fatigue crack propagationresistance for the T7651 temper possessed an obvious improvement on the side of that for the T651 temper, which was alsosupported by fracture appearance, including tearing ridge, tearing dimple and fatigue striation. The precipitation observationshowed that the T651 alloy contained GPI zone, GPII zone and ηʹ phase while the T7651 alloy possessed ηʹ phase and η phase.Compared with the T651 temper, matrix precipitate for the T7651 temper distinctly owed an expanding of size distributionand an enlargement of average size while cuttable phase still remained the dominance for both tempers. Grain boundaryprecipitate and precipitate free zone manifested no obvious difference between the two aging tempers. Cut and bypass mechanismsof dislocation–precipitate interactions were used for explanation and it revealed the reinforced cuttable phase was infavor of enhancing fatigue crack propagation resistance. A theoretical model which directly correlated FCP rate with matrixprecipitate characteristics was employed to calculate FCP rate by substituting quantitative precipitate characteristics and thecalculation results were vaguely consistent with the experimental measurement, which proved its reliability and feasibility.

A new method for ship inner shell optimization based on parametric technique

Yan-Yun YU,Yan LIN,Ming Chen,Kai Li 대한조선학회 2015 International Journal of Naval Architecture and Oc Vol.7 No.1

A new method for ship Inner Shell optimization, which is called Parametric Inner Shell Optimization Method (PISOM), is presented in this paper in order to improve both hull performance and design efficiency of transport ship. The foundation of PISOM is the parametric Inner Shell Plate (ISP) model, which is a fully-associative model driven by dimensions. A method to create parametric ISP model is proposed, including geometric primitives, geometric constraints, geometric constraint solving etc. The standard optimization procedure of ship ISP optimization based on parametric ISP model is put forward, and an efficient optimization approach for typical transport ship is developed based on this procedure. This approach takes the section area of ISP and the other dominant parameters as variables, while all the design requirements such as propeller immersion, fore bottom wave slap, bridge visibility, longitudinal strength etc, are made constraints. The optimization objective is maximum volume of cargo oil tanker/cargo hold, and the genetic algorithm is used to solve this optimization model. This method is applied to the optimization of a product oil tanker and a bulk carrier, and it is proved to be effective, highly efficient, and engineering practical.

Structural and Running Safety Assessment of the Handling and Distributing System in Automated Container Terminal Considering Container Vehicle-Truss Bridge Coupled Vibration

Lu Kai-liang,Yan Wei,Ye Hao,Bao Yan,Liu Xiang-rui 보안공학연구지원센터 2013 International Journal of Security and Its Applicat Vol.7 No.4

Test Study of Emotional Characteristics of Fashion Brands Based on Big Data Text Analysis

이암(Yan LI),장준청(Jun Qing ZHANG),Dan Qing SHI(Dan Qing SHI),Kai CHENG(Kai CHENG) 한국컴퓨터게임학회 2023 한국컴퓨터게임학회논문지 Vol.36 No.1