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Water is the source of life and an essential resource for our global economy. It empowers agricultural and industrial production and development, and fosters the nature and ecosystems. With increasing water scarcity, growing population, climate change and extreme weather conditions, together with stricter water regulations, decline in ore grade and increasing controversy on water use between mining operations and local communities, effective governance of shared water resources and protecting water quality is an economic imperative and social responsibility for mining companies. Water Footprint Assessment (WFA) is a holistic methodological framework that allows integrated assessment for operational and supply-chain water use and the associated water footprint sustainability in different sectors at various spatial and temporal scales. This paper presents a WFA for two copper products – copper cathode and copper concentrate produced by Zijin Mining (China) based on the data from 2012 and 2013. The aim of this study is to evaluate the water consumption within the operations and supply chains, to understand the product sustainability and identify water footprint reduction targets to minimize its associated social and environmental impact on natural resources in the catchment. The two copper products were produced from two different processes, hence their different associated water footprints. Evaporation due to the vast area of heap leach pad is the main contribution to the blue water footprint (WF) for copper cathode whereas supply chain WF is negligible. The grey WF is found to be due to total copper concentration in the effluent discharge. This assessment goes beyond water footprint accounting stage and includes the environmental sustainability of the direct water footprint. Opportunities for efficiency improvement across the two processing plants and prevention strategies to reduce impacts on the environment are also discussed. The comprehensive approach makes the WFA unique from other water use assessments and shows its value in water sustainability strategy making.

Tag collision problems seriously affected the performance of the RFID system. In order to solve this problem, we proposed an improved Recession Binary Tree Algorithm to avoid duplication and redundancy search, so that system throughput can substantial increased in the case of there have large quantities of labels.

Al-5Ti-1C master alloy refiner was prepared by melt reaction method, and its refining efficiency was examined by purity aluminum in the paper. The microstructures under different process conditions were studied by OM, SEM and XRD. The results shown that the grains were finer, TiAl3 and TiC phases were uniformly distributed at 900¡æ, held time for 15min. The refining efficiency was best at addition of 0.4% (wt.%) refiner and held time for 10min.

Rural dwellings have a big difference in the appearance and envelope. Living form is changing a lot from detached house to the apartment in multi-story apartments. These changes affect building’s energy consumption consisting of heating and cooling. This paper focuses on the impact of the energy consumption affected by different surface volume ratios, simulation analysis showed a general argument of the difference. And for the same house type, this paper also compares the energy-saving effect of different envelop performances, Specific contents are the heat transfer coefficient and shading ways. Simulation results identified that SVR has influence on different types of houses, the energy consumption of row houses can be saved more than 30% compared with detached houses. Envelope performance also affects energy consumption and the national standard is recommended for the energy saving and the comfort.

Realistic prediction of concrete creep is of crucial importance for the safety, durability and long term serviceability of concrete structures. High performance concrete (HPC) contains combinations of various components, such as aggregate, cement, water-reducing agent and other ingredients which affect the properties of the HPC including creep. This paper reviews the accuracy of the conventional concrete (CC) creep prediction models, including B3,GL2000 and CEB-FIP(2010). Further, a new creep prediction model based on the comprehensive analysis is proposed. The improved model was calibrated through a joint optimization of laboratory creep tests. Comparisons of the results of the proposed methold with 76 data points of creep coefficient showes good agreement.

The masonry building takes a majority of town housings in these areas. Unlike the experimental study, the Finite Element Analysis is an important part for better comprehension of the finite element method and can reduce the investment and manpower. The aim of this paper is to simulate the structural response from the variety of masonry buildings under earthquake excitations by using finite element software called ABAQUS. There are four models of the masonry building with different storey, which include the one without constructional column and ring beam, with constructional column only, with ring beam only and with constructional column and ring beam simultaneously. In the process of modeling, we adopt the integrated model and regard walls, constructional columns, slabs and steels as homogenous continuums. Furthermore, we adopt concrete damaged plasticity material model to simulate the material of building and input El Centro earthquake wave N-S component. The result of analysis shows that setting ring beams or constructional columns can significantly improve the integrity of the building and reduce the mises stress on foundation. The result of analysis has a significant guidance on masonry building construction in seismic region.

An in depth state-of-art review is done on the topic,constitutive relations of masonry under compression. 12 constitutive models of masonry proposed by scholars from home and abroad are presented in the paper. These models can be classified into four types. Merits and drawbacks of each constitutive relation are discussed. Ten typical constitutive relations are selected to make comparisons. Results show that the ascending branch of curves has few differences, major differences occur in the descending branch of curves. Besides, two experimental data are used to analyze the models and results are discussed. Furthermore, some suggestions on this topic in future research are presented.

As the key element of Huizhou culture, Hui-style architecture is one of the masterpieces of Chinese ancient architectures. The Hui-style architecture was highly praised by architecture masters both at home and abroad because of its phenotypic features, such as black tiles, white wall, and horse-like wall; its decoration features, such as tile carving, wood carving, stone carving; and its living features, such as high house, deep well, large lobby. Since most of the Hui-style architectures were built long time ago, had not been repaired for many years, as well as influenced by different kinds of natural hazards, the Hui-style architectures were decayed, eaten by worms, or damaged by fire to different degree. Most of these architectures could not meet the living requirements nowadays with faint light, high humidity, poor sound insulation, badly cracks and corrosion of all kinds of wood components; and needed to be repaired and reinforced badly. Based on this situation, the author believes that the Hui-style architecture would be in its original appearance in front of the word in the near future if the scientific research and proper reinforcement measures were adopted for the reinforcement of the Hui-style architectures.

Chinese ancient architectures are valuable culture heritages for human beings, and most of these ancient architectures are timber structures.[ Since most of the survived ancient architectures were built long time ago and suffered all kinds of nature disasters, their structures were damaged severely, and needed to be effectively reinforced and repaired. As the key element of Huizhou culture, Hui-style architecture is the representative of Chinese ancient architectures. Based on Hui-style architectures current damage situations, this paper studies the strengthen methods and current study situations of the timber structure of the ancient architectures from beam, column, mortise and tenon joint, corbel bracket, retaining structure and other aspects. It also studies the shortage of the traditional reinforcement methods, and discusses the usage of the new reinforcement material CFRP in the timber structure of the ancient architecture. In the end, the writer believes that finding sufficient methods to ensure the reinforcement effect, overcoming the shortage of the traditional reinforcement method, as well as ensuring the original appearance of the components when carry out the reinforcement, is the direction of the reinforcement study of Hui-style architecture in the future.

The system for well-logging data designed for data files unified management, can offer a function based on data query and download, also can offer instant replays for data curves. This system contains some functions following that format converting, uploading, query, download and preview for well-logging data curves. All system is designed by software Delphi GDI+.

Design a working condition monitoring and intelligent diagnosis system for screw pump based on the ATT7022 chip. Achieve real-time acquisition, storage, analysis of the driving motor electrical parameters of three-phase voltage, current, frequency, active and inactive power, power factor, and the fluid parameters of screw pump production well pressure, pressure, temperature. Accomplish monitoring, alarm and automatic protection the screw pump failure of rod breaking, pump sticking, vacuum, lack of power phase. Using PIC microprocessor to automatic compensate the screw pump motor power, to improve the work efficiency.

Designed thermal collector conversion device based on the principle of thermoelectric power generation. This device used the LTC3108 module which was low input voltage boost converter. The device can convert the heat from the screw pump working into electricity. The electricity can be powered microprocessors and sensors.

A molten pool image gathering system is designed based on multiple visions. By using a composite filter, it can effectively overcome the interference of the welding arc and obtain a clear molten pool image. A series of image processing algorithms has been proposed based on the features of the molten pool image. A median filtering has been used to remove the noise of the molten pool image. A canny multi-threshold method has been used to extract the edge characteristics of the molten pool. Then the edge feature of the molten pool can be gotten after false edge removing and iterative fitting.

A three layer feed-forward neural network is developed for speech recognition for industrial robots. The signal is made up by four kinds of command sound. Based on the steepest descent method, the BP network is trained by an improved learning algorithm in which momentum factor and learning rate adjustment is adopted. The simulation results indicates that the error in classification small also with high recognition correct in terms of a percentage.

In this paper, the average intensity and the effect of focus on it for disyllabic words in Chinese is analyzed. It is found that, under focused condition, the average intensity of rhyme in the first syllable is comparatively great, while for the onset, due to intervocalic voicing, that in the second syllable is great. Focus has great effect on intensity. Under focused condition, the overall intensity will increase. The results from this study will be applicable in speech engineering.

Hydrazine hydrate catalytic reduction (HHCR) is a green, eco-friendly method to reduce aromatic nitro compound to aromatic amine. Fe-Ni/C composite catalyst for HHCR was prepared. Preparation conditions of Fe-Ni/C composite catalyst were investigated taking o-chloronitrobenzene’s hydrazine hydrate catalytic reductions as the examples. Experimental results showed that the optimal conditions were as follows: preparation temperature is 50 °C, catalyst carrier is nitric acid treated activated carbon, w(Fe) is 5% and w(Ni) is 0.2%. During the preparation, ultrasonic treatment is also helpful to improve catalytic efficiency of Fe-Ni/C composite catalyst. The newly prepared Fe-Ni/C composite catalyst has combined the advantages of noble metal catalyst and iron-based catalyst and features good reduction selectivity and high catalytic efficiency.

A new practical and efficient route was developed for the synthesis of 6,7-dihydro-5H-cyclopenta[b]pyridine, which is a key intermediate of cefpirome. Leading to the formation of the corresponding product, nucleophilic addition, acetylization, Vilsmeier cyclization reaction and dechlorination were employed under mild reaction conditions by using commercially available cyclopentanone and benzylamine as raw materials. The total yield of this newly developed synthetic route for the target product was 43.15% with 99.7% of purity (HPLC). The structure of target molecular was confirmed by LC-MS and 1H NMR spectrum.

Al3+-doped ZnO nano-powder was prepared by sol-gel process, using tin tetrachloride and titanium tetrachloride as starting materials. The crystallinity and purity of the powder were analyzed by X-ray diffraction spectrometer (XRD). And the size and distribution of Al3+-doped ZnO grains were studied using transmission electron microscope (TEM) and scanning electron microscope (SEM). The results showed that the Al3+ was successfully doped into the crystal lattice of tin oxide and that the electric conductivity of Al3+-doped ZnO sample was improved significantly.

In this paper we use queuing theory to analysis the incoming traffic, developed an effective way to control the traffic of a circle by using stop signs and yield signs,and calculated the traffic capacity and average waiting time of this method. Then, we use signals to control the traffic and improve the original method by a analysis the ways the car can pass through the circle crossing. Taking into account of the traffic flow in the different time of a day, we got the light's signal period to adapt to the features of the traffic flow.

Started from Tung oil, a renewable biomass material of china, a new kind of bismaleimide, Tung oil-based bi-dihydrogen-maleimide (TOBBDHMI) was synthesized by the reaction of methyl-α-eleostearate-maleic anhydride adduct (MEMAA) and 4,4'-diphenylmethane disocyanate (MDI). The optimal conditions for synthesis were catalyst triethylamine dosage 1.0%, mole ratio of MEMAA to MDI 2.4:1, reaction temperature 75°C and reaction time 2 h, which gave yield 82.4% for TOBBDHMI (calculated from MDI). The melting point of the product was 186.6 °C~189.3 °C, initial decomposition temperature was 270 °C and final decomposition temperature was 510 °C, which showed the product has good heat resistance. The target product is potential to be used alone or with other bismaleimide monomers to improve polymeric materials’ heat resistance and/or mechanical properties.

Polyurethane (PU), one of the six main categories of synthetic resins, has been used extensively in industry all over the world. Tung oil anhydride-ester polyol (TOAEP), prepared from the China special vegetable oil, Tung oil, was introduced into PU structure. The mechanical property, heat-resistance and morphological structure of the modified PU were studied. Experimental results showed that the hardness and tensile strength of the modified PU increases as the dose of TOAEP increasing while the elongation at break decreases, and the heat-resistance has been improved after modification. The modified PU’s hard segment phase is compatible with the soft segment phase.

In order to solve the problem of thin plate butt-welded tracking, a welding vision sensing system with a rotund facular laser has been designed. In the vision sense system, each parameter of the interior part has been designed by a variety of experiments. The designed image processing software can precisely identify the position of the joint, based on the optimal designed vision sensor system. The thin plate butt welding experiments have been taken with the designed sensing device. The experimental results show that the vision sensor system with a suitable auxiliary illuminant can obtain satisfying visual image information in stainless thin plate butt-welded.

According to the theory basis of time domain transmission technology, designed a new type of transducer for crude oil moisture measurement. Introducted the measuring principle of time-domain transmission moisture content of crude oil sensor, and designed the signal producing circuit, the machine oscillation circuit, the mixer circuit and phase detector circuit of the sensor. Finally, got the linear relationship between the output voiltage of the transducer and the crude oil moisture rate by testing. The accuracy of measurement is 1% when the water content is 50-100% in the crude oil and it is 2% when the water content is 0~50%.

Due to the difficulties while studying the third-body interface experimentally, the simulation model of the non-fluidized particulate lubrication, which utilized the discrete element method (DEM), is proposed. The results indicate that the peak of load profile and friction force profile is located in the middle of tilting pad under particulate lubrication, which is different from fluid lubrication. The exact position of the peak is moving to the outlet zone with the increasing of shear elastic modulus. Particles with higher shear elastic modulus can decrease the friction factor and increase the load capacity of tribosystem, which provided helpful guidance to engineering application. Meanwhile, the wear should be under control. The study of the micro characteristics which included the average contact force, body energy, contact friction energy and particle kinetic energy has been carried out at the same time, which revealed the connection between macro and micro characteristics of particulate lubrication.

Tung oil is a special biomass resource in China. Tung Oil has the characteristic to be transformed into serial derivatives for its active Conjugated double bond. Especially, tung oil anhydride-ester polyol (TOAEP) can be used as substitute of polyester polyol and/or polyether polyol in the synthesis and modification of polyurethane materials. Through esterification and transesterification, methyl-α-eleostearate-maleic anhydride adduct (MEMAA), a derivative of tung oil, was reacted with ethylene glycol and tung oil anhydride-ester polyol (TOAEP) was obtained. The optimal preparation condition are as follows: p-toluene sufonic acid is used as the catalyst, mole ratio of ethylene glycol to MEMAA is 4:1, reaction temperature is 120°C ~130°C, reaction duration is 8 h. Under the optimal preparation conditions, the yield of TOAEP is up to 88.8% and the hydroxyl value is up to 318.0 mg KOH/g. The structure of TOAEP was confirmed by Infrared spectroscopy (IR).

This paper describes an automation welding control system for Tungsten inert gas shielded (TIG) welding to maintain constant arc length. And using this method can replace manual operation. A voltage transducer was used to avoid high-frequency voltage. And dynamic relation between variation of arc length and voltage are described. A digital Proportion-Integration-Differentiation (PID) controller with identified value has been used modulate the rate of electrode feed mechanism. The mechanism, which driven by Servomotor A, can compensated variation of arc length in welding path. By keeping the arc length constant during the welding process, an elegant appearance and higher quality seam is obtained. The experiment result shows that this automatic control system based on digital PID controller is stable, and can working effectively without operator manipulation.

The sensing capabilities of sensor nodes are affected by various factors in the actual environment, and the ideal disk sensing model is not available in the practical sensor network. In this paper, we proposed an Energy-balance Coverage Algorithm based on Probability (ECAP). The algorithm applies to a limited target point monitoring issues, using the heuristic greedy strategy. The nodes that have a larger detecting probability and higher energy are selected to construct a coverage set. It improves energy efficiency, and extends the lifetime of sensor networks. Experiments also show that the algorithm has high stability.

Effect of weld metal hardening property on the deformation behavior and crack driving force of strength mismatched welded joint with crack has been investigated using finite element method under plain strain condition. The results show that when the apply load is small, there is only small scale deformation around the crack tip, the whole structure is still in linear or small scale yielding condition therefore the weld metal hardening property has no significant effect on crack driving force. As the applied load increasing, the deformation region enlarges and at the same time the deformation level around the crack tip deepens, the increasing of weld metal hardening property decreases the local deformation level, consequently leading to the decreasing of the crack cracking force.

In order to investigate the debonding failure mechanism,the distributions of interfacial shear stress between cracks and the influence of preload of on the ultimate load and interfacial shear stress,one reference beam and five beams strengthened with CFRP and steel plate at different level of perload were tested and analyzed.The experimental result indicated that the perload level has less influence on the ultimate capacity.Moreover,when debonding failure of sheet-end interface of concrete beams strengthened with CFRP and steel plate is avoided,the debonding failure of reinforced beams at perload level will occur in the position of midspan.At last,on the basis of cross-sectional equilibrium and compatiable conditions,an analytical model of interfacial bond shear stress is obtained, meanwhile the analytic model favorably matched with the experimental results.

Based on the static test of large-scaled prestressed steel concrete frames, the behavior of crack were tested and investigated. In this paper, according to theory of reinforced concrete members, Code for design of concrete structures(GB 50010-2002)and code ACI 318—05, the formulas of cracking moment considering secondary axial forces were deduced and verified by test results. Conclusion can be drawn as follow: the calculation errors of formulas derive from theory of reinforced concrete members is small, generally less than 6%; the errors of formulas referring to Code for design of concrete structures(GB 50010-2002)is about 10%, which is satisfy the needs of engineering and simply to be calculated; Cracking moment calculated by formulas referring to code ACI 318—05 is less than test result, it is unsafe for engineering application.

This subject studies the mutual effect between the upper structure and the foundation of the long-span spatial structure in the process of construction, normal use and carrying capacity. It compares different foundation forms which can withstand relatively large levels of thrust. The internal force analysis models of the most common form-prestressed tie rod are established and a systemic design theory about the long-span spatial arch space structure is formed. This subject fills the research gap on the foundation design of the long-span spatial arch structure.

Safety assessment about source of hazardous chemicals is an important element in the safety production management. Its model has been introduced, moreover, a series of factors which can affect inherent hazard and real danger have been analyzed in this essay. A mathematical model can be established and put into practice. Through specific analysis of the realities of the Source of Hazardous chemical, it is easy to find that real danger has to do with many factors: Technology level, equipment level, the degree of the quality of personnel. These factors can offset and control the risk, therefore the real risk has been greatly reduced compared with the inherent risk.