A Joint Allocation Algorithm of Computing and Communication Resources Based on Reinforcement Learning in MEC System

( Qinghua Liu ),( Qingping Li ) 한국정보처리학회 2021 Journal of information processing systems Vol.17 No.4

For the mobile edge computing (MEC) system supporting dense network, a joint allocation algorithm of computing and communication resources based on reinforcement learning is proposed. The energy consumption of task execution is defined as the maximum energy consumption of each user's task execution in the system. Considering the constraints of task unloading, power allocation, transmission rate and calculation resource allocation, the problem of joint task unloading and resource allocation is modeled as a problem of maximum task execution energy consumption minimization. As a mixed integer nonlinear programming problem, it is difficult to be directly solve by traditional optimization methods. This paper uses reinforcement learning algorithm to solve this problem. Then, the Markov decision-making process and the theoretical basis of reinforcement learning are introduced to provide a theoretical basis for the algorithm simulation experiment. Based on the algorithm of reinforcement learning and joint allocation of communication resources, the joint optimization of data task unloading and power control strategy is carried out for each terminal device, and the local computing model and task unloading model are built. The simulation results show that the total task computation cost of the proposed algorithm is 5%-10% less than that of the two comparison algorithms under the same task input. At the same time, the total task computation cost of the proposed algorithm is more than 5% less than that of the two new comparison algorithms.

Thermally Healable Polyurethanes Based on Furfural-Derived Monomers via Baylis-Hillman Reaction

Qinghua Huang,Fanghong Yang,Xingxing Cao,Zhongyu Hu,Chuanjie Cheng 한국고분자학회 2019 Macromolecular Research Vol.27 No.9

Two novel acrylate monomers with diol group, 2-hydroxyethyl 2-(furan- 2-yl(hydroxy)methyl)acrylate and methyl 2-(hydroxy(5-(hydroxymethyl)furan-2- yl)methyl)acrylate, were synthesized via Baylis-Hillman reaction in moderate yields. The monomer 2-hydroxyethyl 2-(furan-2-yl(hydroxy)methyl)acrylate was obtained from furfural and 2-hydroxyethyl acrylate (HEA); methyl 2-(hydroxy(5-(hydroxymethyl)furan- 2-yl)methyl)acrylate was prepared from 5-hydroxymethl furfural (HMF) and methyl acrylate. The monomer 2-hydroxyethyl 2-(furan-2-yl(hydroxy)methyl)acrylate reacted with toluene diisocyanate (TDI)-derived or hexamethylene diisocyanate (HDI)-derived diisocyanate oligomers to obtain the corresponding linear polyurethane oligmers PU-1T and PU-1H. Similarly, the diol methyl 2-(hydroxy(5-(hydroxymethyl)furan- 2-yl)methyl)acrylate reacted with TDI- or HDI-derived diisocyanate oligomers to obtain the corresponding linear polyurethane oligmers PU-2T and PU-2H. The numberaverage molecular weights of the linear polyurethane oligomers are approximately 300-350 Da. There are furan groups in the linear polyurethane oligomers PU-1T, PU-1H, PU-2T and PU-2H, which makes them capable of undergoing reversible Diels-Alder reaction with 4,4'- bismaleimidodiphenylmethane (BMI) to form the corresponding crosslinked polyurethanes CPU-1T, CPU-1H, CPU-2T and CPU-2H. Pencil hardness of CPU-1T, CPU-1H, CPU-2T and CPU-2H are 3H, 2H, 2H and HB, respectively. Glass transition temperatures of CPU-1T, CPU- 1H, CPU-2T and CPU-2H are 104.8, 97.6, 5.1 and 1.2 oC, respectively. TGA analysis shows that Td90 values of the CPUs range from 180 to 250 oC. Furthermore, the reversible crosslinked polyurethanes CPU-1T and CPU-1H can be completely self-healed at 90 oC for 3 h, while CPU-2T and CPU-2H can self-heal at 80 oC for 3 h presumably due to their low glass transition temperatures.

Resonance analysis of cantilever porous graphene platelet reinforced pipe under external load

Qinghua Huang,Xinping Yu,Jun Lv,Jilie Zhou,Marischa Ray Elvenia 국제구조공학회 2022 Steel and Composite Structures, An International J Vol.45 No.3

Nowadays, there is a high demand for great structural implementation and multifunctionality with excellent mechanical properties. The porous structures reinforced by graphene platelets (GPLs) having valuable properties, such as heat resistance, lightweight, and excellent energy absorption, have been considerably used in different engineering implementations. However, stiffness of porous structures reduces significantly, due to the internal cavities, by adding GPLs into porous medium, effective mechanical properties of the porous structure considerably enhance. This paper is relating to vibration analysis of fluidconveying cantilever porous graphene platelet reinforced (GPLR) pipe with fractional viscoelastic model resting on foundations. A dynamical model of cantilever porous GPLR pipes conveying fluid and resting on a foundation is proposed, and the vibration, natural frequencies and primary resonant of such a system are explored. The pipe body is considered to be composed of GPLR viscoelastic polymeric pipe with porosity in which Halpin-Tsai scheme in conjunction with the fractional viscoelastic model is used to govern the construction relation of nanocomposite pipe. Three different porosity distributions through the pipe thickness are introduced. The harmonic concentrated force is also applied to the pipe and the excitation frequency is close to the first natural frequency. The governing equation for transverse motions of the pipe is derived by the Hamilton principle and then discretized by the Galerkin procedure. In order to obtain the frequency-response equation, the differential equation is solved with the assumption of small displacement, damping coefficient, and excitation amplitude by the multiple scale method. A parametric sensitivity analysis is carried out to reveal the influence of different parameters, such as nanocomposite pipe properties, fluid velocity and nonlinear viscoelastic foundation coefficients, on the primary resonance and linear natural frequency. Results indicate that the GPLs weight fraction porosity coefficient, fractional derivative order and the retardation time have substantial influences on the dynamic response of the system.

Lactobacillus delbrueckii ssp. lactis R4 Prevents Salmonella typhimurium SL1344-Induced Damage to Tight Junctions and Adherens Junctions

Qinghua Yu,Liqi Zhu,Zhisheng Wang,Pengcheng Li,Qian Yang 한국미생물학회 2012 The journal of microbiology Vol.50 No.4

Cell junctions are the gatekeepers of the paracellular route and defend the mucosal barrier. Several enteropathogenic bacteria can invade intestinal epithelial cells by targeting and damaging cell junctions. It is not well understood how Salmonella typhimurium is able to overcome the intestinal barrier and gain access to the circulation, nor is it understood how Lactobacillus prevents the invasion of S. typhimurium. Therefore, we sought to determine whether infection with S. typhimurium SL1344 could regulate the molecular composition of cell junctions and whether Lactobacillus delbrueckii ssp. lactis R4 could affect this modification. Our data demonstrated that infection of Caco-2 cells with S. typhimurium over 2 h resulted in a redistribution of claudin-1, ZO-1, occluding,and E-cadherin. Western blot analysis of epithelial cell lysates demonstrated that S. typhimurium could decrease the expression of cell junction proteins. However, L. delbrueckii ssp. lactis R4 ameliorated this destruction and induced increased expression of ZO-1, occludin, and E-cadherin relative to the levels in the control group. The results of these experiments implied that S. typhimurium may facilitate its uptake and distribution within the host by regulating the molecular composition of cell junctions. Furthermore,Lactobacillus may prevent the adhesion and invasion of pathogenic bacteria by maintaining cell junctions and the mucosal barrier.

PRODUCTS OF DIFFERENTIATION AND COMPOSITION OPERATORS FROM THE BLOCH SPACE AND WEIGHTED DIRICHLET SPACES TO MORREY TYPE SPACES

Qinghua Hu,Songxiao Li 대한수학회 2017 대한수학회지 Vol.54 No.2

In this paper, we characterize the boundedness, compactness and essential norm of products of differentiation and composition operators from the Bloch space and weighted Dirichlet spaces to analytic Morrey type spaces.

Experimental research on load-bearing capacity of cast steel joints for beam-to-column

Qinghua Han,Mingjie Liu,Yan Lu 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.56 No.1

The load transfer mechanism and load-bearing capacity of cast steel joints for H-shaped beam to square tube column connection are studied based on the deformation compatibility theory. Then the monotonic tensile experiments are conducted for 12 specimens about the cast steel joints for H-shaped beam to square tube column connection. The findings are that the tensile bearing capacity of the cast steel joints for beam-column connection depends on the ring of cast steel stiffener. The tensile fracture happens at the ring of the cast steel stiffener when the joint fails. The thickness of square tube column has little influence on the bearing capacity of the joint. The square tube column buckles while the joint without concrete filled, but the strength failure happens for the joint with concrete filled column. And the length of welding connection between square tube column and cast steel stiffener has little influence on the load-bearing capacity of the cast steel joint. Finally it is shown that the load-bearing capacity of the joints for H-shaped beam to concrete filled square tube column connection is larger than that of the joints for H-shaped beam to square tube column connection by 10% to 15%.

Progressive Collapse Analysis of Large-span Reticulated Domes

Qinghua Han,Mingjie Liu,Yan Lu,Chenxu Wang 한국강구조학회 2015 International Journal of Steel Structures Vol.15 No.2

The paper presents the progressive collapse analysis of large-span reticulated domes based on Alternate path (AP) method. Nonlinear buckling analysis is conducted on a large span roof with two different structural layouts. The results show that although large-span single-layer reticulated dome has a certain redundancy. When 10 key elements or 3 key nodes were removed, the single-layer reticulated dome under the service load would cause progressive collapse. Therefore the protection of key nodes of this structure should be strengthened. However, the redundancy of large-span double-layer reticulated dome is 7 to 13 times that of single-layer reticulated dome. When 10 key elements or 3 key nodes were removed, the double-layer reticulated dome under the service load would not cause progressive collapse. Hence, the resistance to progressive collapse of large-span double-layer reticulated dome is better than that of large-span single-layer reticulated dome.

Static push-out test on steel and recycled tire rubber-filled concrete composite beams

Qinghua Han,Ying Xing,Jie Xu,Zi-Lin Li 국제구조공학회 2015 Steel and Composite Structures, An International J Vol.19 No.4

Recycled tire rubber-filled concrete (RRFC) is employed into the steel-concrete composite structures due to its good ductility and crack resistance. Push-out tests were conducted to investigate the static behavior of steel and rubber-filled concrete composite beam with different rubber mixed concrete and studs. The results of the experimental investigations show that large studs lead a higher ultimate strength but worse ductility in normal concrete. Rubber particles in RRFC were shown to have little effect on shear strength when the compressive strength was equal to that of normal concrete, but can have a better ductility for studs in rubber-filled concrete. This improvement is more obvious for the composite beam with large stud to make good use of the high strength. Besides that the uplift of concrete slabs can be increased and the quantity and width of cracks can be reduced by RRFC efficiently. Based on the test result, a modified empirical equation of ultimate slip was proposed to take not only the compressive strength, but also the ductility of the concrete into consideration.

Active Shimmy Control Method for Driverless Electric Vehicle Considering Unknown Sensor Measurement Error and Nonlinearities

Qinghua Meng,Heyang Zheng,Long-chuan Guo,Chih-Chiang Chen,Zong-Yao Sun,Chuan Hu 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.7

The driverless electric vehicle with electric wheels may generate the front wheel shimmy phenomenon more easily. How to mitigate or even eliminate the shimmy phenomenon by active control method is necessary. The current active shimmy control methods do not consider the sensor measurement error. But the sensor measurement error always exists in practice because of sensor design, manufacturing, and external disturbances. Therefore, this paper investigates this issue. Firstly, a one-degree-of-freedom shimmy model of the front wheel is built. The dynamic function of this model is obtained via Lagrange’s theorem. Then, the shimmy control system with unknown sensor measurement error and nonlinearities is presented. A dual domination control method is proposed to construct a linear state observer as well as an output feedback control law for the shimmy control system. By the Lyapunov method, the designed controller is proved to stabilize the shimmy system globally asymptotically. Finally, simulations are carried out to verify the effectiveness of the one-degree-of-freedom shimmy model and proposed dual domination control method.

Business-Driven Process Fragment Selections in RESTful Business Processes

Qinghua Lu,Xiwei Xu,Weishan Zhang,Liming Zhu,Shanshan Li 보안공학연구지원센터(IJUNESST) 2015 International Journal of u- and e- Service, Scienc Vol.8 No.1

Past work showed that runtime adaptability of business processes can be improved by applying Representational State Transfer (REST) to design and implementation of business processes. However, the existing solutions for RESTful business processes (RESTfulBP) were focused on manual selection of process fragments to be composed at runtime. In this paper, we propose solutions that enable semi-automatic selection of process fragment at each decision-making point of RESTfulBP. The new built-in middleware MiniZnMASC can provide user based process fragment advice to knowledge workers in ways that achieve better overall business value while satisfying all existing constraints. In addition, we redesign the architecture of RESTfulBP in order to allow the business-driven decision-making solutions. The solutions are evaluated for feasibility, functional correctness, business benefits, and performance.