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This paper takes a large supermarket as the research object. Based on its adding layer directly without identification, these implementations including reviewing design drawing, witnessed inspections, indoor test and theoretical analysis are carried. The identification results show that: the layer-adding design has a serious problem on the conception; part of the foundation's short concrete column misplaced seriously to its upper concrete column whose maximum is up to 50mm, and between the gap, there are some obvious weak positions existing some crossing pipelines which are filled completely with cement mortar; part of the concrete column's tails have serious phenomenon of cellular pits; the upper steel structure's support system is imperfect and unreasonable; the seismic capability of the blindly adding layer structure could not meet the national code's requirements. Based on the above structure defects, this paper ensure the safety of the adding layer structure through sticking steel's reinforcement method, section enlargement method and adding some structure 's support system.

In order to reveal the impact of reservoir heterogeneity on its recovery and by taking the interlayer heterogeneous and inner layer sand superimposition model (two forms of complexity situation) into account, water flooding experiments have been conducted on parallel connected rock cores, which are selected and artificially casted cores with different permeability, at different injection rates. Experimental results suggested that water displacement recovery is kept decreasing with the increasing of interlayer heterogeneity. when the interlayer permeability ratio (ratio of high permeability versus low permeability) is at about 6.5 and water displacement rate is set at 0.5ml/min, 1ml/min, 1.5ml/min, 2ml/min, respectively, the water flooding experiments indicated that the low permeability recovery increased significantly and low permeability layer became main producer with the increasing of water displacement rate, on the opposite, the high permeability recovery showed no little big change. Laboratory experiments on the model of layer sand body superimposition revealed that the recovery rate of FTRLPTPL model is about 5%~10% higher than that of FTPLPTRL model.(FTRLPTPL is briefed from that flooding from the thick and rich in oil layer and produced from the thin and poor in oil layer. FTPLPTRL is briefed from that flooding from the thin and poor in oil layer and produced from the thick and rich in oil layer.) Analysis on the experiments in different reservoir inner situation told us that recovery enhancement of low permeability layer can play a significant role in increasing the overall recovery rate.

Liquid production per unit thickness is the important indicator which reflect production capacity, and it is magnitude is the radio of well’s daily fluid production rate and sandstone thickness. It is an important job for petroleum reservoir engineering to study the effect of different sandstone thickness type combination to liquid production per unit thickness. Each sandstone thickness type has different size of reservoir thickness, porosity, permeability, etc.so the different sandstone thickness type will produce different degrees of influence to the size of liquid production per unit thickness. The relationship between each sandstone thickness radio and liquid production per unit thickness is obtained by studying all kinds of sandstone thickness radio under different liquid production per unit thickness.

α-Hydroxy amides are a class of important intermediates in organic synthesis. It plays an important role in the field of science and medicine. However, the preparation methods of α-hydroxy amides are relatively few, and they are usually enzyme-or Lewis acid-catalyzed reactions. These types of methods are not ideal in operation, yield and/or stereoselectivity. We found a new way to synthesize α-hydroxy amides by transforming amino acids into α-hydroxyl acids, and then by amination of the α-hydroxy acids.

Euler-Lagrange (Euler-Lagrange, EL) mathematical model was established according to the topology of TNPC (T-type Neutral Point Clamped) PV grid-connected inverter. Based on the mathematical models and passivity-based control theory, the approach called injecting damping was adopted to design the passivity-based controller of the inverter. The passivity-based controller can decoupled-qaxis current at AC side of the grid and achieve unity power factor, the total harmonic distortion of grid-connected current is low, and the passivity-based controller also make the inverter have good dynamic and static performances. Simulation results show that the designed passive controller of TNPC PV grid-connected inverter is feasible.

In order to improve the performance of the rectifier under unbalanced voltage condition, this paper adopts port-controlled Hamiltonian dissipation (PCHD) control strategy. On the basic of the mathematical model of the three-phase voltage source PWM rectifier, its PCHD model in synchronous dq coordinates was established by orthogonal transformation. The desired equilibrium point of the system was obtained according to the target of the design. The controller was designed with the method of interconnection and damping assignment, and the PI control method was introduced to restrain the steady-state error of DC side. Simulation results show that the designed control system has perfect static and dynamic performances and robustness.

Based on the theory of the chute can achieve single excitation longitudinal and bending vibration, design chute horn with longitudinal bending vibration . Using finite element analysis method combined with experiment,research on vibration characteristics of horn with longitudinal bending vibration, obtained the resonance frequency and the amplitude of longitudinal and bending of the horn, in different angle and the number of chute .Verified it can realize longitudinal bending complex vibration by opening chute on the horn, and in the different chute, and gained variation of the resonance frequency and the amplitude of longitudinal and bending of the horn, in different angle and the number of chute ,to lay the foundation for the two-dimensional ultrasonic vibration in ultraprecision cutting.

Planar targets have been widely used in the field of machine vision, and reordering the feature points on a planar target is of great difficulties and importance. As the current methods for that are of poor robustness, and are easily interfered by foreign objects or the image background, a novel method, which is of high versatility and is not easily affected by the interferences, is proposed in the paper. Cross ratio invariance and homographic relationship between the target plane and the image plane are utilized in the method. Experimental results show that the method is viable and robust to realize precise reordering of the feature points on planar targets in complex site environment.

Due to the problems of the traditional mixed injection molding production, such as unsatisfactory of the injection molding machine cylinder temperature control, the dispersed devices, the low automation degree and the lack of supervision for the whole production process, the production line of the mixed injection molding machine has been modified. The fuzzy self-adaptive PID control method is used to improve the temperature control accuracy and stability. Two sets of equipments of the injection molding machine have been communicated via the bus technology to realize automation production. And the computer monitoring system has been designed by VB technology to monitor the operating status and parameters of the entire production process. This transformation design can achieve to shorten production cycle, reduce labor costs and covering area, and also improve the production automation level and efficiency.

Welded rectangular steel tubular joints have been widely used in large span complicated steel structure engineering .With the type of the joints and structural measures complicated, there is no suitable joints theory formula in design specifications. In this paper, two different structural measures types of umbrella steel truss # 8 joints and 68 # joints in a Railway Station are static analysis ,which is by means of finite element software ANSYS and based on the principle of the joints member loading simultaneously. The analysis results show that: in the case of the joints member loading simultaneously, the carrying capacity variation of each member is not uniform coordination; With the different angle between the branch pipe of joints and main pipe, the changes of the degree of stress concentration in the four side surfaces of the member is different. The maximum difference is about 2-fold; compared 68 #joint with 8 # joint, its degree of stress concentration on the overall is small, which prove that structural measures of its domain joints is reasonable.

In order to take full account of the various factors in the car rental system, in this paper, the system dynamics method is applied to the car rental industry demand forecast.First, we analyze the main factors of the car rental system and its causal relationship, and then establish the dynamic model of the car rental system .The final model was validated using the Beijing car rental industry statistics .

The fatigue of grid structures with welded hollow spherical joint under suspending cranes is an issue in both academic and engineering fields at home and abroad. The structural fatigue is mainly caused by the fatigue failure of welded hollow spherical joint with cross-board. In this paper, 16 specimens categorized in KQ-4、KQ-5 and KQ-7were tested stably and efficiently under constant amplitude stress by use of self-designed loading equipment. The testing results show that the form and mechanism of fatigue failure were clarified elementarily. A fatigue curve of welded hollow spherical joint with cross-board, S-N curve, was suggested in this paper based on the statistic regression analysis of the 16 testing results. The constant amplitude fatigue calculation method was established for welded hollow spherical joint with cross-board in grid structure with welded hollow spherical joint by use of allowable stress amplitude method.

In this paper, billet caster mold oscillation have been found that the mold have sinked and swing have became deformed in the operated process, in order to solve the problem, firstly,the billet caster mold oscillation is simulated on dynamics by using Adams; the force of every joining on swinging arm is obtained. Then, the finite element analysis is worked on swinging arm by using Solid Works COSMOS Works; the stress on everywhere is obtained. The place of maximum stress value is found, then reconstruct swinging arm, at last, the maximum stress value of swinging arm is declined and the factor of safety of swinging arm is increased. So the problem of mold sunk is solved.

Surface roughness is the most important index of product surface in grinding. Bayesian network model was built about process parameters and surface roughness. The network parameters were learned by grinding workpieces with a CNC surface grinding machine tool. The experiments for giving grinding parameters on Bayesian network prediction model have shown good results.

The bed is a main component of the large precision linear rolling guide CNC grinding machine tool. Its thermal-structure characteristics affect on machine tool’s machining precision and stability directly. In this paper, boundary conditions on the bed of a machine tool factory’s production are analyzed; using FEA method, the bed finite element models for thermal-structure coupling analysis are established and then calculated. By analysis, the simulation of the CNC machine tool operating conditions can effectively obtain the distributions of the bed temperature, thermal deformation and thermal stress; and the results are closed to the true situation.

The crack nucleation and propagation process in ultrasonic grinding engineering ceramics are studied based on indentation fracture mechanics. The study shows ultrasonic grinding can be considered as continuous loading and unloading process in view of a single grain. The loading makes cracks form and preliminarily propagate; while the unloading makes them propagate further and makes the direction of crack propagation offset to the workpiece surface, not so far as to extend to the material interior. In common grinding cracks have extended to the material interior, resulting in deep subsurface crack in the subsurface layers. In this paper, the ground surface of small crack damage can be obtained with large grinding depth in ultrasonic grinding compared with common grinding under the same conditions.

Surface roughness is an important evaluation index of the machined surface quality. The ultrasonic turning mechanism was described in detail and the mechanism reducing surface roughness in ultrasonic vibration turning was obtained in this paper. Meanwhile, ultrasonic turning experiments were carried out to verify the theoretical analysis. Theoretical and experimental research results show that machined surface roughness of quenched steel in ultrasonic turning is very close to geometric surface roughness, resulting in smaller surface roughness than that in ordinary turning.