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According to the construction drawings of the assembly building, various prefabricated components are transported from the factory to the construction site. This study provides definitions of the construction units, building units, ordinary vehicles, motor vehicles, transportation shifts and transportation completion and quantitatively describes the collocation correlation between prefabricated components, construction units and building units and the substitution correlation between motor and ordinary vehicles. Subsequently, a transport vehicle deployment problem was proposed for prefabricated components. The objective of the optimization was to maximize the degree of completion of transportation. The constraint of the collocation correlation between prefabricated components and the substitution correlation between transport vehicles is proposed as a substitution equilibrium point method to deploy transportation vehicles. Simulation experiments showed that considering the matching correlation between prefabricated components and the substitution correlation of transport vehicles, the transport completion of prefabricated components could be increased. The substitution equilibrium point method proposed in this study exhibited a lower time complexity than the integer programming branch-and-bound method.

Facing a great deal of Lifelog data and complex information, how to extract valuable information and making it easily understood for users is the most urgent and important issue. This paper introduces a method to find personal trajectories from a Lifelog dataset named informative lifelogging which the author collected over the past 8 years. After introducing the Lifelog system and the data structure, this paper propose a method to find personal trajectory in the dataset. Experiment result in the last chapter shows the correctness of this method. The method proposed in this paper provides some way of managing and retrieving the Lifelog data efficiently.

The authors began collecting personal informative lifelogging data in 2011. The data collected in this article is a discontinuous data set, each of which includes one or more images, a GPS message, a description of a location, and a description of the text, we call this informative lifelogging. However, for the purposes automatically building a story from a huge collection of unstructured egocentric data presents major challenges. This paper first introduces the structure and characteristics of the collected data and uses the DB-scan algorithm to classify the data. Then a model for generating a story is proposed, and a model of story generation based on a story template is proposed in the model. The author implemented a complete software system through code, described a story generation model, and gave the key algorithm to generate stories. Through this system, 418 stories were generated automatically, of which 62% of the stories were particularly accurate. The experimental results verify that it is feasible to automatically generate stories based on personal Informative lifelogging data.

In this paper, the event-triggered adaptive distributed observer is applied to solve the problem of cooperative output regulation for discrte-time linear multi-agent systems. Firstly, we propose two distributed event-triggered strategies, one is relative threshold event-triggered strategy, the other is switching threshold event-triggered strategy. Then we apply these two event-triggered strategies to an adaptive distributed observer, which does not need each follower to know the leader’s matrix information, so it can be fully distributed. Finally, the effectiveness of the method is illustrated by digital simulation.

The drive system provides power for high-speed motorized spindle which performance has a direct impact on the machining accuracy of numerical control (NC) machine tools. The motorized spindle drive system has a great influence on high precision computer numerical control (CNC) machine tools. This paper proposed a current hysteresis control design method based on the semi-physical simulation model for a motorized spindle driven system. The control system built-in Simulink could be packed and download to a digital signal processing (DSP) chip to verify the performance, which will save testing time and reduce development costs. A verification case was presented, and the results showed that the proposed semi-physical model was effective and could be used to accelerate the development of a driven system for motorized spindle.

Motion control is the core of motorized spindle control system. The variable-voltage variable-frequency speed regulation system of motorized spindle is often called variable-frequency speed regulation system. Since slip power does not change with rotational speed during speed regulation, the speed range is wide and the working efficiency is high at both high and low speeds.

High-speed machining technology can solve many difficulties in manufacturing of mechanical products, such as obtaining special machining accuracy and surface quality.

Modern high-speed CNC machining center features high rotational speed of spindle, high operational precision and high machining efficiency. The improvement of speed and precision is based on high-precision dynamic balance.

Problems such as non linearity, parametric changes, disturbance and noise exist in the drive system of high-performance motorized spindle. The solution of these problems is the key to improving the control precision and control performance of motorized spind drive system.

Dynamic imbalance and vibration of high-speed spindle are important factors affecting machining accuracy.

This paper solves the leader-following consensus problem for a class of second-order multi-agent systems with input quantized by a newly proposed adaptive dynamic quantizer. The novel dynamic quantizer is an adaptive quantizer that combines the logarithmic quantizer and the uniform quantizer by introducing dynamic gain parameters to achieve quantizer adaptive adjustment. It has advantages of logarithmic, uniform, and adaptive dynamic quantizers in ensuring reducible communication expenses and acceptable quantizer errors for better system performance. On this basis, we transform the guide way climbing frame (GWCF) under ideal conditions into a second-order multi-agent system and solve the motion synchronization problem of GWCF. Finally, we illustrate our approach by numerical examples.

The positioning problem between the concrete distributor and the distributor area is one of the most important factor affecting the automatic distribution, in the production of precast concrete (PC) components. The detection system for the pre-calibration is designed based on photoelectric switch and encoder through in-depth analysis of concrete distribution technology in this paper. On this basis, considering the influence of reinforcing bars on the detection of magnetic-side-molds in the distribution area, the pre-calibration realization method of concrete distributor is designed by reasonably planning the traveling path of the distributor. This method can locate the pre-calibration point effectively, reduce the labor intensity of workers, and help to improve the automation level of the distributor.

Using response surface methodology, two-target parameter mathematical models for a 100MD60Y4 motorized spindle are established using biogeography-based optimization. Air supply pressure, fuel supply rate, and oil supply interval are the independent variables, while the spindle temperature increase and oil mist PM2.5cumulative volume distribution percentage are the response variables. Biogeography-based optimization is used to find a set of optimal lubrication system parameters with the constraint of a small temperature increase in the motorized spindle at 30,000 r/min while considering the influence of oil mist particle size on environmental quality. After lubrication system parameter optimization, comparing the particle size distribution density and temperature increase between the biogeography-based optimization model’s calculated values and the experimental test results, the errors were 1.8% and 1.17%, respectively.

Since a nonlinear relationship exists between the position coordinates of the rotation axes and components of the tool orientation, the tool will deviate from the required plane, resulting in nonlinear errors and deterioration of machining accuracy. Few attempts have been made to obtain a general formula and common rules for nonlinear error because of the existence of various kinematic structures of machine tools with orthogonal configuration. This paper analyzes the relationship between the deviation of cutter location points and motion of tool orientations. Five-axis CNC machine tools are divided into two groups according to the configuration of the two rotational joints and the home position. Motions of the tool are regarded as a combination of translation and rotation. A model for error calculation is then built. The maximum deviation of the tool with respect to the reference plane generated by the initial and the final orientation is used to quantify the magnitude of the errors. General formulas are derived and common change rules are analyzed. Finally, machining experiment is conducted to validate the theoretical analysis. The research has important implications on the selection of a particular kinematic configuration that may achieve higher accuracy for a specific machining task.

Tooth wear is one of the main reasons that lead to gear failure. The amount of wear is nonlinearly related to temperature, lubrication, load, and various random factors of materials, with obvious randomness and slow time-varying characteristics. Wear is a nonstationary random process, which has no accurate mathematical model or accurate reliability estimation method. This article proposes a reliability model of spur gears which works under a nonstationary random process that exceeds the limit, and the time-varying wear reliability is studied based on the level crossing analysis method. The wear at tooth root is revised in the calculation under the nonstationary random process, and the reliability curves are obtained afterwards. An experiment is carried out on the spur gear meshing test rig, and the reliability model and wear performance are verified and analyzed. Results obtained with the proposed tooth surface wear reliability model match well with the experimental results. Therefore, this model is applicable for situations under a nonstationary random process. The new method makes contribution to the assessment of gear running status and is of great significance in the prediction of wear life under a nonstationary random process.

The thermal error of the motorized spindle has great influence on the accuracy of the NC machine tools. In order to reduce the thermal error, the increase type PID control algorithm is adopted for the control system which can make the temperature controlled in reasonable range. In accordance with the control object features, the Application of the control algorithm is realized in MCU System. Finally, the experiments are carried out which verified the validity and effectiveness of the design of temperature control system by analysis of the experimental data.

Study the prominent characteristics of ZigBee technology on wireless sensor networks, especially on the power consumption of the nodes. In order to reduce the power consumption of wireless sensor network node, this paper simulate the relation between the power consumption and the signal to noise ratio for the communications modulation, the relation between the power consumption and the transmission delay for the sleep mechanism, and the relation between the power consumption and the network throughput for MAC, by hardware structure and MAC protocols of the physical layer of the wireless sensor network node. And analyse the power consumption of the wireless sensor network node further. The modulation of PSK consumes the least power in all of the modulations of the wireless sensor network node obviously; the power consumption of EEMAC is the lowest in the MAC. The results show that the algorithm of EEMAC and the modulation of PSK are very compatible with the cooperations of many nodes. These results are very helpful to the structure optimization of the wireless sensor network node of ZigBee and the reducing of the power consumption of transfer data.