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Properties of the ore were studied by chemical analysis and Lead phase. Research shows that the lead tailings contains 15.47 g/t of silver and 0.62% of lead, lead minerals are mainly Galena, Anglesite and Finnemanite, Silver minerals and galena symbiosis, besides, gangue minerals are mainly quartz. Based on properties of the tailings, flotation feasibility pilot study was conducted. Results show that excellent test indexes that a Ag grade of 137.09 g/t with a Ag recovery of 55.27% and a Pb grade of 5.85% with a Pb recovery of 60.35% were obtained under the used process and reagent system conditions.

The global logistics supply chain enter the competition of modern enterprises. It has been transformed into the supply chain competition in the supply chain. Throughout large foreign retail chains, it relies on advanced information technologies and "supply chain management concept" The rapid development form the competitive advantage. Therefore, if our chain wants to gain a foothold in the increasingly fierce competition, it should improve supply chain management. Supply chain management will directly affect the level of the development of enterprises. Articles form current development of chain enterprise information. The analysis of enterprise information chain problems build chain supply information platform. It puts forward measures to achieve information platform construction.

Agro-products processing industry should develop circular economy to alleviate the constraints of agricultural resources and ecological environment to accomplish sustainable development. With the relative theory of industry cluster, circular economy, system science, this paper expounds the connotation and definition of recycling-oriented agro-products processing industry cluster, analyzes the status and existent problems of it in Fujian, constructs the development mode of it which takes three kinds of behavioral agent as the foundation and three cycle ways as the characteristics, and integrates self-organization and organization, finally puts forward some countermeasures to promote the development of it.

Food logistics is a modern logistics system in highly specialized sectors of logistics. The logistics industry has distinctive characteristics. According to the characteristics of modern aquatic logistics, good work is associated with people's livelihood. Products logistics model basically remain in the traditional areas. From the status quo of China's logistics model, through the status of products logistics development research, analyzes the main problems exist in China's aquatic products logistics model. It was constructed based on supply chain management, logistics model supply chain management.

This present paper deals with transform and design of electric-control trunk device for new Beetle. The path generation method is used to synthesis a new linkage mechanism. And the dimensions of this mechanism are optimized by genetic algorithm. Subsequently PWM modulation method is implemented in the microcontroller for inverter and electric control, which responses to the trunk opening, closing and reacting to interference.

Passive control and semi-active control of vibration in mechanical systems have recently successfully been used in automobiles and airplanes suspension systems. These control techniques are able to guarantee the performances of all vibration structures. Unfortunately, the knowledge and data has not been readily applied to human prosthetics. The information collected can be directly applied to accelerate research into dampening for prosthetics. A focus of this paper is on modeling and controlling vibrations by a given impulse onto prosthetic legs. Simulations of using passive control and idealized skyhook dampening are using Matlab to complete. Through model analysis, control variable, simulation procedures and comparison of two modeling, the models have been refined and with idealized skyhook dampening suspension provide significant improvement of the body characteristics compared with passive suspensions.

Vibration exists widely in people's life and production. Modal analysis for vibration system help to improve the running quality of the mechanical structure and prolong service life. This paper build a new discrete multi-freedom model to calculate the flexibility matrix of simple supported beam, and then use the flexibility matrix to calculate its modal parameters with matlab. In order to prove that the result is correct, this paper use classical continuous vibration theory to calculate the normal modal parameters, finding that the two results are basically the same and as the more discrete number, the result of discrete multi-freedom model more close to the result of continuous vibration theory. In view of this, the new discrete multi-freedom modeling method is proved to be true, and it also can provide the discrete modeling reference for modal analysis of complicated mechanisms.

Taken a reinforced concrete beam bridge which has 20 m main span as an example，based on similarity theory，9 scale model beams of T-beam were designed in accordance with CL= 1/4. The test was divided into three groups: test I: contrast beams without reinforcement，test II: reinforced beams without considering the secondary load，and test III: reinforced beams considering the secondary load. The ultimate load，crack propagation，strain of basalt fiber reinforced polymer (a novel FRP material) sheet and the ultimate failure mode of the beams reinforced by BFRP sheet in the cases of test II and test III discussed. By comparing the results of three tests，it shows that (1) the average deflections of test II and test III decreased by 36.7% and28.9% respectively than that of test I; (2) the final average strains of BFRP sheet in test II and test III are 15118 με and 10921 με which are 84. 4% and 61. 0% of the ultimate tensile strain of BFRP sheet respectively，indicating the stiffness of beams is increased after reinforced by BFRP sheet and the reinforcement effect of test II is better than that of test III; (3) all the ultimate failure mode of reinforced beams are brittle failure.

Structural and optical properties of MgxZn1-xO (x=0.23) thin films grown by radio frequency (R.F.) magnetron sputtering and annealed with different temperature (from 100°C to 400°C) are reported. The films were single-phase, highly c-axis oriented and wurtzite structure. The transmission spectra, recorded in the visible range, reveal a high transmission coefficient (about 95 %) in the obtained films. Besides, when the annealing temperature is 100°C, the crystalline grains are smooth, compact and uniformly distributed. As the annealing temperature increases from 100°C to 400°C, the crystalline grains get larger, but the annealing temperature does not influence optical transmittance obviously.

CIGS thin films were prepared by selenization of Cu-In-Ga-Se precursors, as a new method, the effects of selenization temperature on the properties of CIGS thin films were studied. First, Cu-In-Ga-Se precursors were deposited onto Mo-coated soda lime glass by evaporation and sputtering method. Then, precursors were selenized at various temperatures in N2 atmosphere for 120 min to form CIGS thin films. The degree of reaction and morphology of films as a function of selenization temperature were analyzed. By means of field emission scanning electron microscope (SEM) and X-ray diffraction (XRD), it was found that CIGS thin films selenized at 450°C exhibit chalcopyrite phase with preferred orientation along the (112) plane.

Earthquakes pose a threat to large-scale container cranes. Previous earthquakes damaged many container cranes, which had a significant impact on business interruption losses of the port. In this paper, a container crane’s seismic response is analyzed in ANSYS. First, a finite element model of a container crane is developed. Then, based on the equations of structural dynamics, the four most important modes of the container crane are extracted. Finally, a time history analysis is conducted to obtain the displacements of some critical nodes on the crane model under the excitation of an earthquake wave. The result of this paper provides a reference for the seismic design of container cranes.

The nonlinear dynamic behaviour of sandwich beams with different cores under transverse cycling loads is investigated in this paper. Based on Euler-Bernoulli beam theory, the second-order nonlinear ordinary differential equation of the sandwich beams with different cores is established by applying Hamilton’s principle and Galerkin method. The effects of the cores of metal foam and lightweight wood and porous metal fiber as well as pyramid lattice structure on the dynamic behaviour are studied through numerical simulations. It is shown that the dynamic behaviour of sandwich beams is not solely determined by and

In order to manage the tug better, efficiently and securely dispatch tug operation, and meet the real-time property, accuracy requirements, the GPS chip of embedding RFID for locating and tracking would be used. Through the wireless Radio Frequency technology and Ethernet, it can complete conveying information between tug and harbor dispatching room, then structure the tug locating and tracking information system. It can real-timely acquire and monitor the tug parameter of position, desired track, operating condition and so on. According to that, it makes real-time dispatching. Efficiently achieve the management in harbor pass, operation and assignments all the time and space.

Crack in the port crane which is prevalent in the metal structure of crane is a serious threat to the safety use of crane, therefore, it is very important to study on the production and repair of the cracks. This article takes the actual operating portal crane as an example to study on the crack locations and monitoring methods for metal structure of port crane, with the analysis for the reason of crane load bearing structure’s cracks ,this paper gives the common repair method for metal structure crack for cranes on this basis.

Cadmium sulfide (CdS) thin films with (111) preferential orientation were grown on glass substrates at room temperature by radio frequency (R.F.) magnetron sputtering. The structural and optical properties of CdS films have been investigated by X-ray diffraction, Scanning Electron Microscope micrographs, PL spectra and transmittance spectra. The grain sizes have been evaluated. The transmission spectra of the obtained films reveal a relatively high transmission coefficient (80%) in the visible range. All these results show that the grain sizes increased while the optical band gap decreased with increasing the thickness of CdS films.

This article adopts genetic algorithm to solve the problem of guillotine rectangular stock cutting, and designs a new crossover operator and mutation operator towards the specifical problem, finally gives an example to prove this new genetic algorithm is effective to solve the rectangular cutting problem

It is general preferable to consider stamping effects of sheet metal forming for vehicle crash simulation nowadays. However, the present approaches for stamping simulation and coupling forming results to crash finite element model require massive pre-works. To overcome these difficulties, an inverse method for rapid and simple stamping simulation using HYCRASH is introduced, where crashworthiness analysis of front side rail under frontal crash was used as an example in this study. A detailed stamping simulation by AUTOFORM is used for comparison, also accompanied with the one without stamping effects. Through comparison of stamping results and frontal crashworthiness performance, it is concluded that effective plastic strain makes more contribution on simulation accuracy than thickness reduction, and HYCRASH shows an attractive approach for stamping analysis than AUTOFORM coupled in crash simulation in the context of computational cost.