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Due to the increasing concern on environmental sustainability, many efforts have been made to improve the energy efficiency and reduce carbon emissions of manufacturing processes, including abrasive machining processes. Oilstones, as the abrasive tool of honing machines, are the key parts to remove material. However, the theoretical models and methods that can be used to support the selection of oilstone parameters for reduced carbon emissions are lacking. To fill this gap, this paper proposes a method to optimize shape and distribution of abrasive grains for minimized carbon emissions while maintaining surface quality. First, the carbon emissions boundary is defined, and a carbon emissions calculation model is established from a macroperspective. As each grain contributes to the total carbon emissions, the behavior of grains during honing is then described and analyzed to obtain the carbon emissions model from a microperspective. Surface area of oilstones and the required total volume of material removal are kept constant to meet the physical size limit of oilstones and machining requirement of workpiece. Third, a shape and distribution optimization model is developed to minimize carbon emissions. A modified particle swarm optimization (PSO) algorithm is adopted to solve this problem. Finally, the proposed method is applied to a case study to validate its effectiveness. Results show that carbon emissions can be reduced by up to 30% using the proposed model. The proposed method provides a new green manufacturing strategy for the honing process and a possibility to customize abrasive tools to meet the environmental challenges.

Background The aim of this meta-analysis was to determine whether genetic polymorphisms in the osteoprotegerin (OPG) gene contribute to increased risk of cardiovascular disease (CVD). Material/Methods Electronic databases were searched carefully without any language restriction. Analyses of data were conducted using STATA software. Odds ratios (OR) and 95% confidence intervals (95%CI) were also calculated. Results Seven clinical case-control studies that enrolled 1170 CVD patients and 1194 healthy subjects were included. The results indicated that OPG gene polymorphism might be closely associated with susceptibility to CVD, especially for rs2073617 T>C and rs2073618 G>C polymorphisms. Ethnicity-stratified analysis indicated that genetic polymorphism in the OPG were closely related with the pathogenesis of CVD among Asians (all P0.05). Conclusions Our meta-analysis provided quantitative evidence that OPG gene polymorphism may be closely related to an increased risk of CVD, especially for rs2073617 T>C and rs2073618 G>C polymorphisms.

In service-oriented manufacturing mode, a large amount of enterprises open their workshops to provide manufacturing service, and production outsourcing and customer satisfaction are two crucial manners to make profits. In service oriented manufacturing workshops, jobs come from different customers. Competitive relationship among customers should be inevitably taken into account owing to the openness characteristic of workshops and interests’ maximization pursuit of each customer. Moreover, because of increasing energy price, carbon tax policy, carbon label policy, most of customers and manufacturing companies are urgently eager to reduce energy consumption to save cost. Based on above-mentioned requirements, in this paper, a non-cooperative game model for job shop scheduling based on individual profits maximization in service oriented manufacturing environment is given. It takes customer’s cost as optimal objectives in which energy cost of manufacturing process and transportation process are considered. Finally, one case is carried out to validate the rationality of the proposed model.

Environment settlements should be noted in the city tunnel construction, especially on the Yangtze embankment. Wuhan Yangtze River tunnel is the first one in the world third long river, and the embankment settlements is engineering significant to Wuhan, a city with 9 million people. The Wuhan Yangtze River Tunnel is introduced, and the settlements induced by the shield tunnel are investigated. The tunnel, the soil and the embankment are numerical simulated in FEM model. The settlements of the foundation surface are calculated with difference shield face positions, and engineering advices are obtained based on the calculation.

We study theoretically the electronic and transport property for an armchair-edge graphene nanoribbon (CNR) with 12 and 11 transversal atomic lines, respectively. The GNR is irradiated under an external longitudinal polarized high-frequency electromagnetic field at low temperatures. Within the framework of linear response theory in the perturbative regime, we examine the joint density of states and the real conductance of the system. It is demonstrated that, by numerical examples, some new photon-assisted intersubband transitions over a certain range of Geld frequency exist with different selection rules from those of both zigzag-edge GNR and single-walled carbon nanotube. This opto-electron property dependence of armchair-edge GNR on field frequency may be used to detect the high-frequency electromagnetic irradiation.

This paper investigates theoretically the electronic structure and transport of a two-level quantum dot irradiated under a strong laser field at low temperatures. Using the method of Keldysh equation of motion for nonequilibrium Green functions, it examines the time-averaged density of states and conductance for the system with photon polarization parallel with and perpendicular to the tunnelling current direction respectively. It is demonstrated that, by analysing some numerical examples, more photon sidebands resonance states and multi- and single-photon transitions are found when diagonal matrix elements dominate the interaction, while the electronic transitions due to multiphoton absorption are more or less suppressed when off-diagonal interaction dominates.

The spin current in a parabolically confined semiconductor heterojunction quantum wire with Dresselhaus spin–orbit coupling is theoretically studied by using the perturbation method. The formulae of the elements for linear and angular spin current densities are derived by using the recent definition for spin current based on spin continuity equation. It is found that the spin current in this Dresselhaus spin–orbit coupling quantum wire is antisymmetrical, which is different from that in Rashba model due to the difference in symmetry between these two models. Some numerical examples for the result are also demonstrated and discussed.

This paper put forward and analyzed the concept “virtual procedure database” (VPDs)operating system learning rate by using generalized stochastic Petri net, to analysis the performance of VPDs operating system. With the isomorphism relation between generalized stochastic Petri net and Markov chain, will meet the learning rate of the VPDs operating system of GSPN is transformed to the equivalent Markov chain model through using GSPN and Markov chain methods, to assess the performance of VPDs operating system, and verified by an example, provided the basis and reference for optimized VPDs operating system.

We study analytically the moving nonlinear localized vibrational modes (discrete breathers) for a one-dimensional Klein-Gordon diatomic lattice in the whole omega (q) plane of the system by means of a semi-discrete approximation, in which the carrier wave of the modes is treated explicitly while the envelope is described in the continuum approximation. We find that both pulse and kink envelope moving modes for this lattice system can occur with certain carrier wave vectors and vibrational frequencies in separate regions of the omega (q) plane. However, the kink envelope moving modes have not been reported previously for this lattice system.

For the micro-displacement of high precision which wanted in reconstruction technology based on image sequences is difficult to achieve. This paper presents a new super-resolution reconstruction technology based on multi-images of random micro-offset. First of all, a sequence image acquisition device based on template is build. We can use the good optical characteristics of template to make accurate calculation of the micro-displacement without suffering the cost of obtaining a certain micro-displacement. Secondly, we present the mathematical model for random micro-displacement based sequence images reconstruction. It can be used to achieve any multiples of high resolution images using any multiple low resolution images. Experiment shows, the algorithms discussed above can effectively increase the true resolution of images.

A new direct approach based on the Fourier transformation is developed and applied to study the perturbed sine-Gordon equation. Since a new basis for perturbation expansion is introduced, the first-order correction is expressed in terms of Bessell functions.