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Multi-depot heterogeneous vehicle routing problem with simultaneous pickup and delivery and time windows (MDHVRPSPDTW) is an extension of vehicle routing problem (VRP), MDHVRPSPDTW mathematical model was established. The improved genetic algorithm (IGA) is proposed for solving the model. Firstly, MDHVRPSPDTW is transferred into different groups by the seed customer selecting method and scanning algorithm (SA).Secondly, IGA based on elite selection and inversion operator is used to solve the model, and then cutting merge strategy based on greedy thought and three kinds of neighborhood search methods is applied to optimize the feasible solutions further. Finally, 3-opt local search is applied to adjust the solution. The proposed IGA has been test on a random new numerical example.The computational results show that IGA is superior to branch and bound algorithm (BBD) by Lingo 9.0 in terms of optimum speed and solution quality, and the model and the proposed approach is effective and feasible.

Aiming at vehicle routing problem (VRP) with many extended features is widely used in actual life, multi-depot heterogeneous vehicle routing problem with soft time windows (MDHIVRPSTW) mathematical model is established. An improved ant colony optimization (IACO) is proposed for solving this model. Firstly, MDHIVRPSTW was transferred into different groups according to nearest depot method, then constructing the initial route by scanning algorithm (SA). Secondly, genetic operators were introduced, and then adjusting crossover probability and mutation probability adaptively in order to improve the global search ability of the algorithm. Moreover, smooth mechanism was used to improve the performance of ant colony optimization (ACO). Finally, 3-opt strategy was used to improve the local search ability. The proposed IACO has been tested on a 32-customer instance which was generated randomly. The experimental results show that IACO is superior to other three algorithms in terms of convergence speed and solution quality, thus the proposed method is effective and feasible, and the proposed model is better than conventional model.

This article attempts to make an empirical analysis on the food quality and safety information sharing degree between retailers and partners of supply chain and its influencing factors. In the paper, the degree of EDI, Bar Code and POS technologies used by retailers represent the degree of food information sharing. The results showed that the general situation of food quality and safety information sharing among partners in supply chain is more optimistic; factors of the publicity frequency, demand scale and sharing willingness of food information influence significantly on the degree of information sharing between retailers and other partners. Different factors affect the ways of information transfer. Finally, in order to ensure retailers offer safety food to consumers, government should take proper measures to ensure food information transfer effectively in supply chain.

In order to study the application of the liquefied natural gas (LNG) on diesel engine, a turbocharged diesel engine was converted into a dual-fuel engine ignited by diesel fuel. The effects of load ratio on fuel economy and emissions of dual-fuel engine were compared and analyzed at engine speed of 1200 r/min, 1600 r/min and 2200 r/min. The experimental results show that, the specific fuel consumption is reduced with the increase of load ratio at different speeds. As the load ratio increases, CO emission of dual-fuel reduces, but it increases slightly at high loads and full load. When the load ratio is less than 40%, HC emission of dual-fuel is reduced significantly with the increase of load, but increases when the load ratio continues to increase, and finally HC emission is stable. When the load ratio is less than 40 %, NOx emission is relatively low, as the load ratio increases, increases sharply, but at high loads and full load, reduces slightly.

Green procurement, as a new procurement model, has made tremendous progress in recent years, but read through the existing literatures, we found the lack of systematic collation of existing research. This paper collated and analyzed the relevant existing literature, discussed from selection and evaluation of green supplier, the influence of implementing of green procurement, countermeasures for further development of green procurement three aspects. In the end, this paper pointed out the lack of existing research and future development direction. As inductive summary of previous research results, this article maybe will inspire and guide the researchers in this area.

The main structure and key components of the precision EDM equipment are analyzed and researched in this paper. Key components such as main structure, A-axis, W-axis and R-axis are designed. Aimed to machine several kinds of diameters on a work piece, an on-line electrode milling method is studied. And then test this method on an EDM machine. Based on the test results, the functional relation between diameters and the wears of the electrode is confirmed by the least square method. According to this function, the efficiency of the EDM machining for the precision micro-holes is improved.

A new time-frequency analysis method based on mutual information and EMD-WVD time-frequency analysis is proposed. The method uses EMD to decompose signals into independent intrinsic mode functions (IMF), uses the mutual information of EMD intrinsic mode components and original signal as basis to determine EMD false modal component, and uses WVD of EMD true Intrinsic Mode to reconstruct the WVD of original signal for feature information extraction. ICE fault signal time-frequency analysis results show that the proposed method can effectively improve the accuracy of WVD time-frequency analysis, and correctly analyze characteristics of the signal.

In terms of energy and environmental purification, application of photocatalytic purification in energy and environment is getting increasingly widespread. In the present paper, it focused on the applications of photocatalytic technology in indoor air purification. Photocatalyst and photocatalytic reaction devices are the two issues in photocatalytic air purification. Fe-La co-doped TiO2 was prepared, and integration of photovoltaic-thermal circular photocatalytic air purification reactor was designed, which showed high air purification efficiency. The experimental data and theoretical analysis gave the support to exploit new indoor air purification technologies. Further, technical and economic analysis on photocatalysis technology with photovoltaic-thermal integration applying in indoor air purification was studied and helpful results were attained.

Eco-compensation for Coastal Principal Function Zoning (CPFZ) is a novel and important research topic. This paper chooses the coastal area of Xiamen Bay as the study area, and attempts to research on the eco-compensation under the framework of CPFZ. At first, the paper discusses the connotation of eco-compensation for CPFZ, and points out that the main consideration should be given to two aspects: the compensation for losses of coastal ecosystem services caused by the leading industry, and the compensation for losses of the restricted or prohibited industries due to the leading industry priority. Then, based on the framework of CPFZ in Xiamen Bay, this article estimates the losses of ecosystem services caused by the leading industries and the corresponding eco-compensation amount, as well as the losses of the restricted or prohibited industries and the reference amount of the claim, using the valuation of ecosystem services combined with the expert judgment method, and the market price method, respectively. Finally, the compensation approaches and the relevant policy are suggested. This work will be helpful to promote the operability of CPFZ and provide reference for further related researches.

400kg/m3 apparent density foam concrete consists of protein foaming agent, ordinary Portland cement and two types of polypropylene fibers is made in this study. The effects of two types of fibers (polypropylene linear fiber and polypropylene mesh fiber) on the compressive strength, flexural strength and water absorption of the foam concrete were investigated. The results showed the difference of the water absorption of the foam concrete with addition of the two types of fibers is not significant, but the difference of the compressive strength and flexural strength is clear. Moderate addition of fibers could improve the strength of the foam concrete. As compared with control, the compressive strength and flexural strength increased by as high as 60.7% and 71.2%, respectively. From the experimental results, it is clear that polypropylene linear fiber has advantage of compressive strength and flexural strength over polypropylene mesh fiber when mixed with foam concrete.

The creep characteristics of red layer sliding soil under the condition of different vertical loads and water contents were studied through a series of direct shear creep tests. Tests results showed that the water infiltrated to the sliding zone along the fissure of red layer sliding belt due to the crush of red layer sliding rock, leading to softening of sliding zone and acceleration of shear creep. When the shear stress reached the limit of long-term shear strength, sliding soil was broken suddenly with small vertical loads (50 kPa and 100kPa), while the sliding soil presented as a constant acceleration creep with enough vertical loads (200 kPa and 300 kPa). The inflection point in shear stress-shear displacement isochronous curve corresponded to the long-term strength of the soil.

In order to analyze the vibration performance of partially-filled liquid tank of ships, this paper takes the integration of measures including numerical simulation with finite element method and experimental verification with LMS vibration test and model analysis system of steel liquid tank under different liquid level conditions to study the fluid-structure interaction phenomenon. With the software of ADINA, the FEM model of the tank is developed and the model analysis which indicates the vibration modes and natural frequencies is completed. The simulation is compared with the experimental results which shows the natural frequency of the structure decreases with the level increases.

The similitude requirement of excited load was deduced to maintain the consistent vibration between scaled model and prototype structure, based on the modal theory of multi-DOFs systems. The similitude of load frequency was another demand to maintain the consistent vibration, with the similitude of structure size and load magnitude. The dynamic similitude problem of a liquid tank was studied by finite element method and test analysis respectively. The results show that the similitude of load frequency is the insurance for the consistency of prototype and scaled model structures vibration. In a case the magnitude error of displacement is 8% to 10%, and the displacement and acceleration have all changed distinctly without the similitude of load frequency. All the results indicate that the similitude of load frequency is the key factor to analyze the scaled model dynamics correctly.

Balanced cash flow is the foundation of enterprise survival and growth. Investment and finance activities are the most prominent factors that affect enterprises cash flow. So appropriate investment and finance scale is very important to get appropriate production capacity and healthy cash flow at the same time. In order to determine the suitable investment and finance scale of the enterprise, investment and finance scale analysis model is studied in this paper.

As lignocellulosic biomass, the cornstalk should be pretreated before anaerobic fermentation for hydrogen production. In this study, HCl, NaOH and enzyme were employed for cornstalk pretreatment and the products were used for anaerobic biohydrogen production. Hydrogen yield and hydrogen production rate were investigated to optimize cornstalk pretreatment method. In addition, the economic effect and energy consumption were also considered to evaluate the pretreatment methods. The optimum cornstalk pretreatment method was soaking in 2% NaOH at 50°C for 48h with a hydrogen yield of 55.0 ml/g-TS and a hydrogen production rate of 6.5 ml/h/g-VS in anaerobic hydrogen production.

For the limitations of HHT of the internal combustion engine vibration signal analysis, and the problem of WVD cross-term suppression methods existing aggregation and cross-term component suppression conflicting, the time-frequency analysis method based on EMD white noise energy density distribution characteristics of the internal combustion engine vibration is proposed. First, the internal combustion engine vibration signal was decomposed into the independent series intrinsic mode function (IMF) with different characteristic time scales by using EMD decomposition method. Then, based on the energy density distribution characteristics of the white noise in EMD decomposition, used the distribution interval estimation curve of the IMFs energy density logarithm of white noise with the same length of the original signal as cordon for false pattern component, identified and eliminated false mode component of vibration signal IMFs component, analysised of each IMF with Wigner-Ville. Finally, the Wigner-Ville analysis results of each IMF were linear superposed in order to reconstruct the original signal time-frequency distribution. Simulation and engine vibration time-frequency analysis results show that this method has an excellent time-frequency characteristics, and can successfully extract feature information of the internal combustion engine cylinder head vibration signal.

The Poly(L-lactic acid)(PLLA)/surface-grafting silica(g-SiO2) nanocomposites were prepared by melt blending. The isothermal crystallization behavior of PLLA/g-SiO2 nanocomposites with different content of g-SiO2 was investigated by optical depolarizer. In isothermal crystallization from melt, the induction periods and half times for overall PLLA crystallization (95°C Tc 120°C) were affected by the crystallization temperature and the content of g-SiO2 in nanocomposites. The results showed that g-SiO2 as a kind of heterogeneous nucleating agent can reduce induction periods and half times for overall PLLA crystallization. The thermal properties of PLLA/g-SiO2 samples were also investigated by differential scanning calorimetry (DSC), The results showed that the crystalline degree of PLLA was improved as the presence of g-SiO2.

In order to solve the flank concave problem of the rotary gear shaving cutter, a new worm type shaving cutter has been manufactured, which will be used on a gear hobbing achieving freedom shaving. And its tooth precision can reach 6-7 level. The main contents includes the worm normal section curve equation of the worm type shaving cutter involutes, the optimization of tooth fitting error and the linear fitting of the tooth curve of the normal section by the MATLAB genetic algorithm toolbox. According to GB/T6084-2001 hob series standard, the results showed that the error theory is less than 1/6 of the AA level.

The study on nonlinear displacement discontinuity model has been investigated in the researches of normal incident wave attenuation across rock joints. But the studies were limited only on the effects of joint with single type deformation behavior, without considering the influence of different extent in model nonlinearity. The improved elastic nonlinear normal deformational model can descript the extent of nonlinearity quantitatively. Based on this model, a displacement discontinuity model for normally incident wave propagation across multiple parallel joints was established in an elastic half-space. Using one-dimensional wave equation characteristics method, the time-domain numerical difference scheme of transmitted particle velocity was proposed, making computational programs to obtain semi-numerical solutions, and transmission coefficients. Parameter studies were conducted to get an insight into the effects of number of joints and the extent of nonlinearity, the incident wave maximum amplitude on transmission coefficients and transmission energy rate, waveform distortion and delay time.

Non-coaxiality has been recognized as an important feature of grain materials in geotechnical engineering. Without considering the non-coaxiality in structure design will lead to an unsafe result. Studies on the non-coaxial soil behaviour have been carried out both using numerical simulation and experimental testing by several researchers. To discuss the non-coaxiality of sand, it is essential to carry out tests under various stress paths. HCA is a valuable device to investigate the soil behaviour under various stress paths. In this paper, a review of the experimental work on non-coaxial soil behaviour especially using HCA is presented to help the understanding of both non-coaxiality and the use of HCA.

In order to solve the problem of tooth concave error appeared in the shaving course of non-modification disk-shaped shaving cutter, the worm type shaving cutter of open groove is studied. Firstly, the basic structure of the shaving cutter and the manufacturing process will be introduced in detail. The angle of front cutting edge is -30 ° or 30 °, and then the coincidence degree is approximately equal to 2, when the tool cut the gear in the direction of the oblique angle. Secondly, the tooth profile precision will be able to be achieved though circular grinding method based on both sides of the worm. Finally, the free shaving principle is discussed by analyzing the shaving movement, the drive speed and the cutting speed. According to the shaving gear experiment, the results show that the tooth precisions reach to the 6 grades.

In this research, nickel/iron (Ni/Fe) bimetallic nanoparticles were used for the dechlorination of para-nitrochlorobenzene (p-NCB) which could be identified in contaminated soil and wastewater. In the reaction, Ni acted as a collector of hydrogen and the Fe was corroded for producing hydrogen gas. p-NCB was rapidly adsorbed onto the surface of the nanoparticles. Then, p-NCB was degraded to p-CAN and reduced to aniline, or dechlorinated directly to aniline. It was indicated that Ni loading ratio, Ni/Fe mass ratio, and reaction temperature could greatly affect the dechlorination process of p-NCB. Under similar conditions, when 6 g/L of nanoscale Ni/Fe was used, the dechlorination efficiencies reached 25.9 and 100% under 0.5 and 2.0% of Ni/Fe mass ratios, respectively. Thus, a negative linear correlation between the reaction rate and the initial concentration of p-NCB (within a range of 20 to 80 mg/l) could be observed. The reaction activation energy of 94.6 kJ/mol was obtained within the temperature range of 15 to 35 °C.

As the living standarda are improving constantly, people are paying more attention to the supplying of safety drinking water. In the rural areas, people are worried about the problem of drinking water supplying. This thesis is taking the rural areas in Zhejiang province as an example to discuss the existing problems of the supplying of drinking water and the options to deal with these problems.

The research of stress wave propagation law under cracked rock has important theoretical value and practical significance. Because of the discontinuity, nonelasticity and nonlinearity of the cracks, the theoretical interpretation and mechanism research about tress wave propagation law are a great challenge to researchers for a long time. From the establishment of the research method, the determination of mathematic model of micro-cracks and the main solutions, this paper brief reviews the current development of the influence of the complicated micro-cracks on stress wave propagation law.

Combining with the outstanding performance of Ti (C, N), such as wear-resistant, withstand high temperature and alkali erosion, Ti-bearing blast furnace slag was modified, and Al-N-based materials were prepared in this paper. Based on the thermodynamic analysis, reasonable formula program was designed by the phase diagram, and then through high-temperature orthogonal experiments, a reasonable process condition was determined. The experimental results showed that the twice firing at the temperature of 1500°C was propitious to carbonitriding reaction. SiO2 was participated in carbonitriding reaction as reactant, which was conducive to the formation of Ti≡N bond. Eventually Al-N based materials that meet the design requirements were obtained.

Product platform design is essentially a difficult decision to make, thus a hierarchic platform has been proposed to solve the inherent tradeoff for optimization. However, architecture coupling adds on complexity of the platform design. This paper proposes an improved cost model for the optimal design of platform design in the hierarchic manner with the consideration of the architecture coupling. This cost model uniquely treats the architecture couplings and their decoupling interfaces as latent cost drivers to enable the flexible design of product platform and its family. As a support, the underlying tradeoff mechanism of platform-based product family design is also analyzed in this paper.

In order to solve centralized installation and cooling problems of airborne electronic equipment with big power and high heat flow density in aircraft, the paper put forward an innovative closed-loop forced ventilation cooling system, expatiated system compositions and operation principles, and also took a cabinet system for example to introduce new cooling system design method and simulation results.

In this paper, Mobile Agent (MA) and a number of intrusion detection system described. Considering the shortcoming of the current intrusion detection system, a new system called the intrusion detection system based on MA was described. Using the autonomy of MA, Intrusion Detection System based on MA avoids single-point failure, and robusts the system. As a result, the security of network has been increased.

Photoelectrocatalytic degradation performance of hexachlorobenzene (HCB) was assessed with a newly designed continuous photocatalytic reactor. CdS/TiO2 NTs were successfully prepared by depositing CdS particles on the surface of TiO2 nanotube arrays.The morphology, phase structure and photoelectric properties of CdS/TiO2 NTs were characterized by field emission scanning electron microscope, X-ray diffraction and diffuse reflectance spectroscopy. The photoelectrocatalytic activity of CdS/TiO2 NTs was evaluated in degradation of HCB in aqueous solution. The experimental results show that CdS/TiO2 NTs exhibited higher photoabsorption rate under visible light, bigger photocurrent (value) and improved photocatalytic activity than TiO2 NTs.

Vanadium was recovered by using technology of calcified roasting→alkali leaching→ion exchange→precipitating→deaminizing, the principles of this recovery process were described in detail. Through the experiments, the parameters of roasting, leaching and ion exchange were determined, a new operational, low-polluting method to recovery vanadium was formed. This method not only can overcame the disadvantage of traditional technology, such as long process, serious pollution, but also has advantages such as high recovery and high purity of vanadium. In this study, pure V2O5 products with national standard were obtained. The total recovery was up to 65% or more, which was higher than that of the sodium roasting methods.

The MgO-Al2O3-Fe2O3 composite was prepared at 1600°C for 3h with magnesia powder and alumina powder as raw materials and with ferric oxide powder as additive. The effect of the molar ratio of MgO/Al2O3 on the sintering and thermal shock resistance of the composite materials was studied. The results showed that increasing the molar ratio of MgO/Al2O3 could improve the densification of the Al2O3-Fe2O3 composites, with the molar ratio of MgO/Al2O3 increased from 3 to 5, densification of the composites didn't increased but decreased. The optimum molar ratio of MgO/Al2O3 of the Al2O3-Fe2O3 composite is equal to 3, the sample MA-3 exhibits better sintering densification and thermal shock resistance. Its primary crystal phases are spinel and periclase, and less amount of sosoloid 20MgO·19Al2O3·Fe2O3. So, the MgO-Al2O3-Fe2O3 composite is acceptable for application in cement rotary kiln linings and high temperature gas filter support.

Using chemical vapor deposition (CVD) method and purified air as carrier and diluent gas, ZnO thin films was prepared with zinc acetate on glass substrate. Crystalline and optical properties of ZnO thin films were respectively tested by X-ray diffractometer (XRD) and UV-light spectrophotometer. The results showed that crystal face (002) of thin films was preferred orientation. In the visible region, the transmittance was over 85%. When ZnO thin films was prepared at 500 °C, the crystallization of ZnO thin films was the best, and when the temperature was 450°C, the grain size of thin films was the least, and internal stress was the least. With the substrate temperature increased, ZnO thin films both showed blue shift of the absorption edge and decrease of band gap.

The composites in the MgO-Al2O3-Fe2O3 system were prepared using high pure magnesia and alumina as raw materials and ferric oxide powder as additive. The effect of sintering temperatures on the sintering performance and thermal shock resistance of the composites was studied. The results showed that both the apparent porosity and linear change ratio of the samples decreased with the increase of sintering temperatures, and their bulk density and bending strength increased accordingly. The sample sintered at 1550°C exhibits excellent thermal shock resistance. The XRD and SEM results indicated that the crystal phase of the samples remained the same, but their microstructure became denser as the sintering temperatures increased from 1500°C to 1600°C. As a result, the composites could be sintered at about 1550°C, which has a potential application in cement rotary kiln linings.

Aiming at the need of on-line performance monitoring and fault diagnosis for diesel generator system, an on-line data acquisition, analysis and diagnosis system based on portable industrial computer, different function sensors and PCL-818HD data acquisition card was constructed. Its design of hardware, software and its test and diagnosis method were given in this paper. Through the vibration signal analysis and on-line fault diagnosis example of generator system, it shows that the diagnosis system can realize on-line performance monitoring and fault diagnosis for diesel generator system.

A new type of oxygenated fuel blend was designed, it was diesel-fuel mixed with 15%、25% n-butoxyether(NBE) in volume. The experiments were conducted on a TY1100 single cylinder DI diesel engine. When the diesel engine rotational speed was 1400r/min and 2000r/min，the effects of the oxygenated fuel blends on engine Combustion and emission characteristics were studied. Results of experiment show that NBE has good solubility in diesel. When the diesel engine without any modification fueled with 15% ~ 25% NBE-diesel blended fuel，in comparison to original diesel engine, the diesel engine dynamic changes little, auto-ignition period is delay, and the premix combustion period increases, while the diffusive combustion period and combustion duration decreases. At high load, the peak values of cylinder pressure, pressure increase rate decrease strongly, but at low load, the peak values decrease slightly. In the same operating condition, the diesel engine fueled with 15% ~ 25% NBE-diesel blended fuel, its smoke, CO, HC and NOx emission decreases with the increasing content of NBE, can significantly reduce the smoke emission and reduce CO、HC and NOx emissions in some extent. For the largest decline amplitude, smoke emission decreases to 75%, CO emission decreases to 56%, HC emission decreases to 76.9%, and NOx emission decreases slightly, it decreases 13.1%.

Joining of TE material to electrode is the key technique in the construction of TE device for the practical applications. In this study, a suitable alloy electrode was introduced into CoSb3-based element by means of spark plasma sintering (SPS). Finite element analysis showed that the maximum thermal residual stress appeared at the cylindrical surface zone close to the CoSb3/electrode interface. Microstructure of CoSb3/electrode was investigated by EPMA and the intermetallic compound (IMC) layers were found. The shear strength of CoSb3/electrode joints was tested and the results show that the joints have sufficient strength for reliability of TE device. Electrical contact resistance between CoSb3 and electrode was measured by means of four-probe technique. The results show that the contact resistance was minimal and below the 50μΩ.cm2, which meant the joint exhibited a good electrical contact. The high temperature reliability evaluation showed good thermal duration stability of the CoSb3/electrode joints.

A novel synthesis method on solvent-free reaction using improved jet milling was described. Synthesis of a schiff base derived from p-hydroxybenzaldehyde and p-aminobenzoic acid had been achieved by solvent-free reaction using improved jet milling, and the structure of the compound have been characterized by Fourier transform infrared spectrometer, 1H nuclear magnetic resonance techniques and mass spectrometry. Differential thermal analysis of reaction process shown that the reaction was complete within 6 min. The scanning electron microscopy shown that the particles of the schiff base were regular and the size of the most particles was 0.5~1 μm. At the same time, the theoretical analysis about reaction process of solvent-free reaction using improved jet milling was preliminary studied. This solvent-free reaction using improved jet milling not only involves mild conditions, a simple operation and short reaction time, but also gives quantitative yield without waste producing work-up procedures. Simultaneously, the investigation also showed this reaction method was feasible, and of benefit to environment.

In this study, we designed a suitable electrode material was designed, Cu-W alloy, which achieved a good thermal match with CoSb3 thermoelectric (TE) material. By means of spark plasma sintering (SPS), Cu-W alloy was introduced into CoSb3/Ti/Cu-W TE element successfully. Finite element analysis showed that the maximum thermal residual stress appeared at the cylindrical surface zone close to the CoSb3/electrode interface. SEM and EPMA results showed that an intermetallic compound (IMC) layer formed at the CoSb3/Ti interface and EDS analysis confirmed the IMC layer was TiSb phase. Shear tests showed that the shear strength of CoSb3/Ti/Cu70W30 joint was about 50Mpa. The potential profile of the interface area was measured by the four-probe method and the result showed no abrupt change in voltage was found around the interface. The high temperature reliability evaluation showed the joint had high thermal duration stability.

The dynamic stress intensity factor was studied about the Griffith crack between the visco-elastic layer and elastic body under shear loading. Adopting integral transform and singular integral equation method, the time response of dynamic stress intensity factor was calculated. Considering the influence of materials parameter, it was found that the dynamic stress intensity factor increases with crack length increasing, and it posses distinct size effect when the thickness of visco-elastic layer reaching the character size of materials.