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Logistics has become "the third profit source", we do the optimization research of storage system based on the power drive-through rack designed by our research group. According to the optimization model and using the Multi-Objective Genetic Algorithms, we take a logistics distribution center as an example. Introduct of cargo weight, quantity and warehousing frequency parameters, mimicing the process of natural selection, mutation and evolution in biological world, following the survival of the fittest mechanism, obtain the distribution of cargo space in Power drive-through Rack. High weight goods is in bottom shelves, making the center of goods gravity more lower. High quantity and frequency goods is near the entrances of warehouse; making the distribution become more reasonable. Improve the efficiency and utilization of warehouse.

In this research we study the demand characteristics and service sensitivity of solar energy water heater products in the whole life cycle, establish the maximum profit model of multi-level inventory system. Adopt the maximum profit model checking the enterprise actual research instance, analysis the relationship of the customer mean demand changes between the optimal service level or the maximum profit, the results show that the maximum profit model can reflect the relationship of the customer mean demand changes between the maximum profit.

The aim of this research was to establish a probabilistic model to predict the growth probability of B. cereus. The five strains of B.cereus were studied and a logistic regression model was chosen to study the interaction of different temperature (10°C, 15°C,20°C,25°C,30°C,35°C), pH(4.5, 5, 5.5, 6, 6.5, 7, 7.5), Aw( 14 levels from 0.992 to 0.932) on the probability of growth. This paper made a fractional factorial design and the experimental data was divided to two parts: 80% of data was chosen as model data and 20% of data was chosen as validation data . At last comparison was made between the predicted values and observed value by choosing 19 experimental data from the published studies. The results showed the concordance index of model data was 0.991 while the validation data was 0.976, indicating that the data was correctly classified and model had a high predictive ability. Also The performance statistics obtained indicate a reasonable goodness of fit of the model obtained, mainly due to the high values of R2-Nagelkerke (0.954) and χ2=0.0119,P=1 of the HosmerLemeshow statistic. A high predictive accuracy is obtained (89.47%) with test data, showing a good predictive ability. In this paper, the growth/no growth model can quantized the combination of environmental factors for B. cereus. This study can help food manufacturers in making decision on the more reasonable and safer formulations for food products in order to prevent the growth of B.cereus along their shelf-life.

The torque vibration derived from in-wheel-motor transmitted to body frame through suspension system without the absorption of mechanical transmission parts, then excited every body panel to shape the vehicle interior noise, which influenced the quality of the vehicle NVH. This paper aims to build an accurate suspension system simulation model to analyze the influence of suspension parts parameters to system vibration transmission property. Basis on a novel empirical model of rubber bushing, a multi-rigid suspension model and a multi-flexible suspension model had been established respectively. The vibration characteristics of two models were simulated, furthermore the swept-sine exciting vertical force signal on wheel contact point were input on the simulation models to find the difference between rigid and flexible model. The simulation results show that: the multi-flexible model can reflect the vibration characteristics of the suspension system more accurately in the high frequency range and so is it more applicable to the simulation analysis of vibration characteristics of in-wheel-motor electric vehicle suspension system.

The foamed cement paste (FCP) is a kind of inorganic insulation material. It is characterized by its light weight, heat-insulating and fire-proofing properties, and the thermal conductivity is close to that of expanded polystyrene (EPS). The foamed cement paste is achieved by means of chemical reaction. The mixture proportion, the preparation process, mechanical and thermal properties are investigated in this paper. The results show that properly mixed paste foams stably, and the bulk density could be controlled. The hardened FCP could be used as insulating filler material in composite walls, as well as blocks for Thermal insulation walls.

Effects of thermal discharge from a coastal power plant on phytoplankton community were determined in subtropical Zhanjiang Bay. Two sampling transects were chosen up and down the Zhanjiang Plant in the Zhanjiang Bay, Nine stations were located along the two transects, which were divided into four zones. Monthly boat cruises were undertaken in the bay at spring up here, tide ebb slack, neap rise open and neap tide ebb slack respectively, during the period April-October 2012. Species diversity (H') showed a distinct increasing gradient from the most thermally polluted zone to the healthy zone. The more distinct gradient occurred at spring tide. Species diversity fluctuated during April-October 2011 and four sampling tide times with no visible patterns. Evenness showed indistinct gradient from the heated water source to the control zone, and fluctuated during April-October 2011 and four sampling tide times with no visible patterns. Species richness, cell count and Chl a concentration at mixed and healthy zones were significantly higher than that at heated zones, with the maximum value recorded at mixed zone, and showed seasonal and tidal changes with no obvious pattern. © (2013) Trans Tech Publications, Switzerland.

Pollutions of livestock and poultry breeding to the environment have evolved into a serious social problem, while phosphorus is a non-renewable resource. This study aims to not only remove the phosphorus in bovine urine wastewater effectively, but also make it recyclable and reduce the load of the follow-up sewage disposal. Choosing the diatomite as the adsorption material, its adsorption effects and the influence factors of diatomite were investigated by static adsorption method, and the adsorption isothermal curves studied. The results showed that the best adsorption condition was as follows, i.e.,taking 50mL bovine urine wastewater with TP 45.67mg/L, when the diatomite dosage was 3.0g, the pH was 7.0, the adsorption time was at 6.0h with the temperature of 30, TP concentrations could be reduced to 9.86mg/L and total phosphorus removal rate reached at 78.41%. Freundlich equation was better than Langmuir equation in describing the behaviour of adsorption phosphorus on diatomite. It is believed that diatomite is feasible to be used as adsorption agent for phosphorus removal from bovine urine wastewater and this promotes the potential of diatomite being used as sewage treatment materials.

The compressive strength of geopolymer prepared from a class C fly ash (CFA) at different curing conditions and mass ratio of water to fly ash were investigated. The geopolymer was activated with a mixed solution of sodium hydroxide (NaOH) and sodium silicate. The results revealed that the obtained compressive strength was in the range of 11.7~61.9MPa and the compressive strength decreased with the increment of the mass ratio of water to CFA (W/F). The geopolymer samples with the highest strength were obtained when W/F was 0.30 with proper delay time 1d before being demoulded and then followed by curing at 60°C for 24h. For geopolymer with lower W/F (0.30), its optimum curing temperature was better not higher than 60°C, however, for the higher W/F, the curing temperature was suit to more than 70°C.

Under variable temperature curing conditions(30 oC ~70 oC), concrete with fly ash whose compressive strength, flexural strength, and dynamic elastic modulus are better than ones without fly ash.Compared with constant temperature 20oC, 50 oC and 70 oC, variable temperature curing(VTC) is benefit for the improvement of mechanical properties of 30% fly ash concrete, but which is no advantage to improve performance of 50% fly ash concrete.

The influence of superabsorbent polymers (SAP) as internal curing stuff on the restrained shrinkage and cracking of concrete was investigated. Results show that SAP in the mortar with slag and silica fume increases the compressive train of the steel ring, but postpones the initial cracking time of the mortar from 5 days to 6.5 days and reduces the crack width by 25% at age of 28 days.

The chloride permeability of concrete with slag or (20wt%, 30wt%, and 40wt% of binder) and binary slag and fly ash (the ratio of slag and fly ash 5:5, 4:6 and 6:4) was investigated in this study. The results show that the chloride permeability of concrete decreases firstly and increases latterly with the increasing of fly ash content. However, the permeability of concrete with slag decreases sharply with the slag content increases. Especially the content of slag is 40 wt%, the permeability is only 15.4% of the control concrete. The permeability of concrete using binary admixture of slag and fly ash is less than that of fly ash concrete and more than that of slag concrete.

Post-embed pullout tests are applied to the concrete cubes of C15-C60. Based on the result of 50 concrete samples, the relationship between pull-out resistance and compressive strength of concrete has been discussed in detail, and the formula used for calculating the concrete strength is given out. Its related coefficients and relative standard can meet the requirement. The simulation method is used on the base of curving failure surface. The paper presents the destruction mechanism of pull-out method in concrete property test, and good correlation between the date of pullout force and cube strength is explained.

The temperature field distribution and thermal stress distribution in concrete has been studied by finite elements method to establish the relationship between the thermal stress and the temperature in this paper. The results show that the maximum thermal gradient and the maximum thermal stress in the concrete appears on the direction of greater structural dimension, and the thermal stress value is positively correlated with thermal gradient or saying temperature difference and elastic modulus, and is negatively correlated with the water content and air content.

Carbonation of concrete for hydraulic structure containing mineral admixtures is studied. It is observed that the fly ash is not benefit to the carbonation resistance, and the different content of fly ash in concrete may play a different role without activator. However, concrete for hydraulic structure using binary admixture of fly ash and slag will make up the defects and when the fly ash to slag ratio is 1:1, the depth of carbonation decreases comparing to concrete using fly ash.

This paper reports on the mechanical properties and plastic shrinkage crack of concrete containing modified polypropylene fibera kind of new porous polypropylene fiber. Results of crack properties tests show that after adding modified polypropylene fiber, crack area, maximum crack width and average crack width of concrete decreased markedly. Results of mechanical properties show that flexural and splitting tensile strength of concrete with 1.0‰ modified polypropylene fiber volume fraction at 28 days increased 24% and 28% respectively compared to the reference concrete; Reticulate polypropylene fiber has less effects than modified polypropylene fiber on flexural and splitting tensile strength. Compressive strength of fiber reinforced concrete changed slightly, but flexural strength and splitting tensile strength increased, and the ratio of splitting tensile strength to compressive strength decreased.

In this study, two rare earth oxides, Y2O3 and La2O3, are used as the additives in the sintering of ZrB2-SiC composites to improve the sinterability and control development of microstructure during densification. The results show that the use of rare earth oxides (5vol.%) improves the powder sinterability, hindered excessive growth of matrix particles and increase fracture toughness of ZrB2-SiC composites, in comparison to ZrB2-SiC with additions free. Nearly full dense materials are obtained by hot pressing at 1900°C. XRD analyses indicate that lanthanum-containing phases were formed in the composite with La2O3. Microstructure observations by SEM reveal that the grain size of ZrB2-SiC with Y2O3 and La2O3 composites are less than the sample without additives, which indicates Y2O3 and La2O3 may restrain the grain growth and increase the fracture toughness. The fracture toughness of ZrB2-SiC composites with Y2O3 and La2O3 reached 5.0MPa·m1/2 and 5.5MPa·m1/2 respectively. Therefore, the additive Y2O3 and La2O3 are very effective as sintering aids for the ZrB2-SiC composite.