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The structure of cylindrical shell with nozzle has been widely used in pressure equipment. The analysis and design for the structure of cylindrical shell with nozzle are generally based on the isotropy of metal at present, which may cause certain error and risk. Because of the approaches of rolling, heat treatment, and so on, the materials’ properties are different along each direction in practical engineering. In this paper, based on anisotropic thin shell theory, the analysis for orthotropic pressurized structure of thin-walled cylindrical shell with nozzle was conducted by using finite element software Ansys. The influences of thickness ratio and elastic modulus ratio were comprehensively considered, and also compared with the stress results under isotropic structure. The analysis results show that the values of stress and stress concentration factor for the structure of cylindrical shell with nozzle decrease with elastic modulus ratio, but increase with thickness ratio. Compared with the influence of thickness ratio, the elastic modulus ratio has significant effect on stress level. The rational use of the material anisotropic property can optimize the structure of thin-walled cylindrical shell with nozzle. The results in present paper provided a reference for the design of orthotropic pressurized structure of cylindrical shell with nozzle.

Uncertainty of parameters like material mechanical properties are traditionally described by probabilistic model, which requires detailed statistical information of parameters limited to obtain in engineering application. In this paper, the problem is solved by using the non-probabilistic convex model that only needs the upper and lower bounds of variables instead of abundant statistical information, which greatly reduces the demand of data and avoids unsafe results caused by the scatter of data. Based on the non-probabilistic convex model, the non-probabilistic interval analysis method is introduced to calculate the creep damage of HK40 high temperature furnace tube and to discuss the influence of operation conditions on creep damage with operation pressure and operation temperature regarded as interval variables. Consequently, the effect of outer wall temperature on creep damage interval is greater at the beginning of furnace tube operation stage. With the increase of running time, the effect of inner wall temperature on creep damage interval is greater and greater, and at the same time greater than that of creep damage interval when the outer wall temperature considered as interval variables. When the operating pressure is treated as interval variable, the upper and lower bounds of creep damage are nearly in a straight line that indicates the effect of pressure change on damage is little. Meanwhile, the life of high temperature furnace tube is predicted according to the definition of non-probabilistic interval index, and the analysis results are compared with the results of probabilistic model. The analysis results sufficiently demonstrate that the non-probabilistic approach presented in this paper is viable.

Strain-based failure assessment methods have been usually used in recent years to propose the fitness-for-service flaws. In this paper, the stress-based and strain-based failure assessment diagram (SB-FAD) approaches were reviewed firstly. Then, SB-FAD approach was used to the material commercially pure titanium TA2 with high strain-hardening coefficient. Several failure assessment curves obtained from strain-based method for four typical specimens, i.e., CCP (center-cracked plate), DECP (double edge cracked plate), SECP (single edge cracked plate) and CT (compact tension) were proposed. It was found that the geometries and crack sizes had obvious effects on the failure assessment curves. By comparing with the stress-based failure assessment curves, the traditional strain-based failure assessment curves could lead to more conservatism in the stage after yielding. However, the SB-FAD modified by Ainsworth can be used.

For C-Si-Mn low carbon HSLA(High Strength Low Alloyed) steel, the influence of microstructure and properties were researched on the different annealing processes. The result showed that the microstructure at room temperature of the steel were polygonal ferrite, island martensite and punctate bainite. With the increase of the annealing temperature, the content of martensite and bainiteincreased and the content of ferrite decreased. Accordingly, tensile strengthincreased from 1069MPa to 1498MPa, and the elongation decreased from 13.8% to 5.1%. With the increase of the overaging temperature, tensile strength decreased from 1315MPa to 1152MPa, and the elongationincreased from8.5% to9.8%. Finally, the optimum annealing process obtained that the annealing temperature was 820°C for 80s, slow cooling to 680°C, water quenching to room temperature, the overaging temperature was 280°C for 300s and air cooling to room temperature. The material obtained higher tensile strength and better elongation.

This paper presents a technique for processing Terahertz radar reflector by SPDT (Single Point Diamond Turning) based on LODTM (Large Optics Diamond Turning Machine). This technique applies single crystal diamond cutting tools for ultra-precision machining, and thus could obtain high-precision optical mirror, which could be used as the Terahertz radar reflectors. An experiment for aluminum sample had been done to demonstrate the availability of the technique, and a pair of Terahertz radar reflectors were obtained. The precision of the reflectors, detected through precision coordinate measuring technology, was better than the designed requirement. The experiment results showed that Terahertz radar reflectors generated by deterministic ultra-precision machining technique based on LODTM would have advantages in figure accuracy and roughness and so on, which could be helpful to improve the precision and low the cost of Terahertz radar system.

In the digital construction process of universities, channels and ways of information dissemination is changing. SMS platform can able to achieve bulk SMS sending and receiving, meeting announcements and emergency notifications. It has been increasingly used by the majority of universities. This paper presents a design scheme of campus short message platform based on smart client. It can be integrated with multiple application of campus network system, provides users with a richer, broader range of SMS services on campus, so as to increase productivity, reduce office costs.

Waste water is becoming more and more around us and phosphates exit everywhere in waste water. Eutrophication, the most common phenomenon caused by phosphate, can lead to water problems. Therefore, searching suitable materials to remove and control phosphate in waste water is of great significance. In this reach project, the method of adsorption was chosen to remove phosphate and two kinds of ceramic clay materials which were low cost and easily available as adsorbent for adsorption were used for phosphate removal. According to the removal efficiency of phosphate removal, temperature, solid to liquid ratio, the original concentration of phosphate and experiment time were studied in the experiments.

This paper specifically addresses the effect of changing the constant temperature region of the sintering temperature curve in manufacturing nickel powder capillary structure (wick) on the performance of a flat loop heat pipe (FLHP). The sintering temperature curve is composed of three regions: a region of increasing temperature, a region of constant temperature, and a region of decreasing temperature, with the sintering time and temperature in the region of constant temperature having significant effect on the permeability of the wick. In this study, for wick manufacturing the temperatures in this region tested range from 550°C to 650°C and the time from 30 minutes to 60 minutes. The properties and internal parameters of the wick are measured, and the wick is placed into FLHP for performance testing. Experimental results show that at sintering temperature of 550°C and lasting about 45 minutes, maximum heat load is 200W, minimum thermal resistance is 0.32°C/W, permeability is , porosity is 66%, effective porosity is 3.8and heat flux is around 21W/cm2; related literatures have only reported maximum heat load increase of 25%.

This research considers a direct sales system facing demand that is sensitive to both sales price and delivery lead time. The behavior pattern of such a direct sales channel is studied by utilizing the developed model, numerical experiment and sensitivity analysis. Our results reveal that when manufacturers’ capacity is set higher, customers would be less likely lost. In contrast, if manufacturers’ capacity is set lower, more potential customers may quickly be lost due to longer lead time. The outcome of analysis shows how major factors influence decision making and profits. Our findings may serve as a practical reference to enterprise in practice.

Structural design and construction process for a subway station consists of two tunnels with large transection are discussed according to its function and geological conditions of rock mass in this paper. A composite lining is designed to support surrounding rock, and partial bench cut method, side drift method are utilized to build the special subway transfer station in rock mass. The practice of the designed scenario proves to be a great success and attains the safe construction of the station by tunneling method.

The paper points out that the figure symbol “ ” should be named as “double zero”, not infinity. “ ” has the similar meaning as “0”. They all express no numerical value. In this paper, the application based on the definition above in probability theory is discussed.

This paper introduced the present situation of the research on "Energy - Economy - Environment" sustainable development, proposed design ideas to build an open service-oriented platform for basic research, presented the detailed design and implementation approaches of the open research platform which provided support, research and decision functions for the “Energy-Economy-Environment” coordinated development .The platform facilitates the related department of government and research staff those who utilize it for depth study, and provides support data and policy-making basis for building the mechanism of energy, economy and environment coordinate development and socioeconomic macro-development goals.

In this paper, the key parameters and functions for quantification of temperature creep stress were offered. These key parameters established the creep-heat-change fluctuation on fully graded concrete. The information is helpful for simulation of super arch dam concrete pouring process.

This paper mathematically described the group selecting problem of intermediate ordnance equipment support agency. Through taking maximizing support ability of the selected group and minimizing support ability differences of each equipment type as the objective function, taking a minimum support ability of equipment, staffing level of the selected group and support agency as conditions, optimization model was put forward. And the effectiveness of the model is validated by the example computation.

The theory of expectation estimation is put forward to discuss the estimation quality of the expectation domain. It is demonstrated that the “validity” criterion of the estimation theory in mathematical statistics (named classic estimate later) isn’t right and arithmetical average value x isn’t the best estimate. The means of characteristic value estimate (N (0, 1) estimate) is suggested to demonstrate the expectation estimate domain.

Rock mechanics parameters are important during engineering investigation, design and construction, especially elastic modulus and Poisson’s ratio. According to the end point of initial fracture compression stage and elastic proportional point of stress-strain curve, the elastic deformation stage was determined; then the modulus and Poisson's ratio of rock at different strain rates were calculated by use of the average method. The results indicate that elastic modulus of rock increases with increasing strain rates; Poisson's ratios are scattered, but also present increasing trend.

Optical fiber sensors with light weight, small size and immunity to electromagnetic interference have been found to be a promising device for use in the development of smart structures. It is well known that the strain transfer from the host structure to the optical fiber sensor is dependent on the bonding characteristics such as adhesive layer and bonded length. In this investigation, the optical fiber sensor is surface bonded on the host structure. A theoretical model consisting of the optical fiber, adhesive layer and host material, is proposed to determine the strain in the optical fiber sensor induced by the host structure. The theoretical predictions were validated with the numerical analysis using the finite element method.

Flowerlike nickel oxide was synthesized by a simple liquid-phase process to obtain the hydroxide precursor and then calcined to form the nickel oxide. The precursor and the nickel oxide were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG) , the scanning electron microscope(SEM) and Brunauer–Emmett–Teller-specific surface area measurement. The results indicated α-Nickel hydroxide was transferred to NiO with a cubic crystalline structure after being calcined at 450 °C; the NiO still kept the morphology of the precursors and the specific surface area of the NiO was 125.2m2/g.

In this paper, by studying the engineering properties of rubber particles-improved fly ash soil, the authors provide technical parameters for setting up cold-resistance layer in the seasonal frozen zone. In the experiment, rubber particles are mixed into the fly ash soil by mass of 0%, 1%, 2%, 3%, 5% and 7% and unconfined compressive strength testing, frost heave test, insulation test and thermal conductivity test. By analyzing the test results, the authors drew the conclusion that fly ash soil improved by rubber particles has a high compressive strength, a small amount of frost heave, good insulation performance, small thermal conductivity coefficient.Therefore, improved fly ash soil with rubber particles is one of the preferred materials to set up the cold resistance layer in seasonal frost zone.

This paper analyzes the modality of two-dimensional photonic crystal micro-resonators by adopting equivalent refractive index mode. In this paper, it controls the optical field distribution only through altering the thickness of light guide layer, while the parameter like resonator structure and crystal lattice arrangement remain stable. It discusses that it would arrive at a satisfactory photon locality while the refractive index of light guide layer material is gallium nitride , the thickness of light guide layer is and its equivalent refractive index is 2.1.This reveals the influence of micro-resonator light guide layer’s thickness towards the modality, providing a preferable pre-estimate method for the actual research of micro-resonators with higher quality.

The design and development of a screw-drive in-pipe robot is presented. The robot is composed of power-driving module, walking orientation module, universal joints, and accessories. The application of automatic spring structure on the robot improves its adaptability. The robot is able to move smoothly in the vertical, inclined, or horizontal pipelines, or even when the cross-section of the pipe is not strictly circular. The calculation formulae of robot walking speed and motor driving torque are derived in this paper. According to the geometries at the bend and the motion constraints, the robot turning capacity and turning condition are also analyzed. The vertical, bend, and other tests are performed on the experimental prototype, demonstrating that the screw-drive in-pipe robot provides sufficient tractive forces and good maneuverability and adaptability.