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Integrated with orthogonal design method and numerical simulation, injection molding process of the Y-type electrical connectors was conducted to study the influence of process parameters on volume shrinkage rate and maximum warpage, which are regarded as product quality indices. The multi-indices valuation model for the main influencing factors of the process is developed. The influencing sensitivity to the multi-objective of the processing parameters, such as melt temperature, mold temperature, injection time and holding pressure, is determined by range analysis. Through analyzing the diagrams of influential factors, the optimized process parameter diagram is obtained and verified by simulation. The optimum parameters minimizing the warpage defect and shrinkage are: melt temperature (528K), mold temperature (338K), filling time (0.6s), holding pressure (100%) and holding time (10s). The results show that it is effective to balance the impact of process parameters on the shrinkage and warpage. The work can provide optimal design and process reference for the quality control and assembly precision.

During selective laser sintering process, different sintering parameters have great impact on the performance of the molded parts, and the degree of influence is different. Using orthogonal test, indirect sintered 316L stainless steel, the compressive strength and precision of the parts were measured and compared to study the influence of various sintering parameters (laser power, scanning speed, scan spacing, preheating temperature) on sintering. The greater degree of influence factors were got by range analysis. The results show that laser power, scanning speed and scan spacing have greater degree of influence on the compressive strength of the parts, and the preheating temperature have less impact. By comparison, the optimum set of parameters was concluded: the laser power is 15W, the scanning speed is 1900mm/s, the scan spacing is 0.125mm, and the preheating temperature is 60°C.

Printed antennas fabricated using conductive ink printed on flexible substrate is low-cost and environmental friendly. The inductance and the quality factor are two important parameters for designing RFID antenna and were studied for the printed RFID antennas. The results show that the inductance is not only determined by the size of the designed RFID antenna but also related to the resistance of the printed antenna coils. The inductance increases with the increasing testing frequency, while the Q value decreases with the increasing testing frequency. The soft magnetic ink prepared with γ-Fe2O3 was used to enhance the inductance of the printed antennas with printing technology. The inductance of the printed antenna with the magnetic core layer is increased by 5.7% at 13.56 MHz.

Magnetic stripe cards and magnetic recording paper are commonly used in credit cards, identity cards, and transportation tickets. Barium ferrite was used to prepare magnetic inks and the magnetic ink was coated onto the paper substrate to obtain the magnetic papers. The crystal structure of barium ferrite was characterized by X-ray diffraction (XRD) and the magnetic property of barium ferrite was tested by vibrating sample magnetometer (VSM) The performance of the magnetic recording paper and the surface morphology of the coating magnetic layer were also characterized. The results show that the magnetic ink based on barium ferrite with the formula of 41wt% of the barium ferrite powder, 14wt% of polyurethane, 36wt% of solvent and 9wt% of PVP has good printing characteristics and the magnetic recording papers have good performance.

This article describes a facile solvothermal method to prepare magnetite (Fe3O4) for electrode material using ethylene glycol (EG) as one of the raw material. The properties were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometer (VSM). The as-prepared Fe3O4 as an electrode material was fabricated into supercapacitor and characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charge/discharge measurements. The Fe3O4 particles disperse well and the size is about 50 nm. Saturation magnetization and coercive force of sample are 90.44 emu/g and 81.84 G, respectively. The specific capacitance is 50.2 F g-1 at 0.5 A g-1.

Face of China's urban problems, we have been thinking how to build a healthy and livable city. The City of Waterloo in Canada, a modern version of Garden City, has given us some inspirations. Briefly summarize the situation of Garden City and the City of Waterloo, analyze detailed why we say the City of Waterloo is Garden City of the 21st century, and point out that they are the same in essence, which is a city with the advantages of both town and country. It shows that it is not impossible to build a healthy and livable city with both advantages in the contemporary. Finally, give a clear explanation of inspirations to the construction of Chinese cities from the City of Waterloo. The inspirations are the followings. The layout of city should conform to the nature; City should give priority to green traffic; Urban commercial, culture, and other service facilities may lay out with appropriate centralized and decentralized; Open Space should retain appropriate original landscape.

The Internet of Things (IoT) technology has been extending its applications in the electric power system since the very beginning of the construction of the smart grid in China. Under such a background, this paper first discusses the technical principles and development goals of the IoT for the electric power system, which can also be called the “power grid IoT” in brief. And then, according to the technical principles mentioned above and the common guidance released by the power grid authorities, this paper presents an IoT technology based Supervisory Control And Data Acquisition (SCADA) system for substations. The key technologies, functions and applications of the system are described respectively. The design of an extremely long-life and stable wireless temperature sensor is presented in detail. The functions of the SCADA system include substation equipment status monitoring, 3D-visualization, environment monitoring, spare parts location, asset management and so on. The applications of such a system can be regarded as efficient methods for substation intelligent operation and maintenance.

In the ground test of inertial navigation algorithm, it is a typical method to use a turntable with high speed and precision to rebuild the air angular motion. As to the difficulty of building a big overload environment in which to get more real output of accelerometers, the method of using current injection to control its output is put forward in this article. Correlation models are established to control the current source card. At the end of the article, there is a brief analysis about real-time performance and precision of current injection.

A aircraft parking position assignment problem is a complex optimization problem with many constrains. In this paper, an assignment model is built with the consideration of constrain treatment. A 2 neighborhood particle swarm optimizer is adopted. The numerical experiment results demonstrate the effectiveness of proposed model and optimization strategy.

The effect of FA and OFA on performances of the soybean protein-isolate/chitosan composite films was evaluated. The FA and OFA enhanced the tensile strength and thermal stability of the composite films significantly, while they reduced the water vapor permeability to 60.3 % and 72.8 % of the control respectively. Moreover, the OFA was more effective to enhance the tensile strength of the composite films than the FA.

The effect of ferulic acid (FA) and oxidized ferulic acid (OFA) on performances of the soybean protein-isolate/chitosan composite films was evaluated. The FA and OFA showed an excellent compatibility and miscibility of in the composite films, and leaded the surface more compact and smooth. The FA and OFA also enhanced the thermal stability of the composite films. The FA and OFA enhanced the performance of the composite films by raising the band energy of the crosslinked molecules.

In this paper, we address the problem to power impairment in amplified WDM communication networks with ROADM (Reconfigurable Optical Add-Drop Multiplexers), in order to improve the performance of communication systems. In dynamic transmission network, we propose a new control strategy that effectively adjusts signal power in the chain network. The results of simulation show that the proposed control strategy could effectively adjust better channel power and reduce the amount of adjustment to achieve transmission performance.

Based on cloud computing distributed network measurement system compared to traditional measurement infrastructure, the use of cloud computing platform measurement data stored in massive large virtual resource pool to ensure the reliability of data storage and scalability, re-use cloud computing platform parallel processing mechanism, the mass measurement data for fast, concurrent analytical processing and data mining. Measuring probe supports a variety of different measurement algorithms deployed to support a variety of data acquisition formats, in the measurement method provides a congestion response policies and load balancing strategies.

As the second line of defense, intrusion detection is the necessary means of getting the high survivability. Intrusion detection technology and its classification is described in this article. And based on the features of Ad Hoc network, the existing new network intrusion detection technology and its characteristics suitable for Ad Hoc network are summarized.

This article aims at the defects in access control strategy of multi-level security firewall, and presents its security classification, scope and access rules for improved methods for the sake of enhancing the security of the firewall.

Evaluation system of financial distress prediction of listed company was established base on the non-financial index cooperated with financial index widespread. And the procedure of the application of unascertained measure model to financial distress prediction was stated in brief. We focused on a certain listed company of Harbin city in Heilongjiang Province, the results showed that the financial risk of this company was moderate-warning according unascertained measure model. It was found that the application of unascertained measure model to financial distress prediction of listed company was feasible. Meanwhile, this method solved the problem of the weight which was presented subjective judgment in market evolution, and promoted the market process fairer and more scientific. The unascertained measure model was very worthy of research significance and prospect.

As the second line of defense, intrusion detection is the necessary means of getting the high survivability. Intrusion detection technology and its classification is described in this article. And based on the features of Ad Hoc network, the existing new network intrusion detection technology and its characteristics suitable for Ad Hoc network are summarized.

With the continuous improvement of science and technology, the management of school students is a very important part of the educational administration and it is the core and foundation of the entire management. Due to further expand of the size of the school, the number of students increased year by year and the management of student situation has become more and more complex. Faced with such a complicated task, if we allow individuals to manage documents, it will be very time consuming. In recent years, with the rapid development of the computer, the computer has shown its great role in all areas of society. Needless to say, the effective introduction of the computer management in school educational administration is very significant for promoting school management system and improving the quality of teaching. For these reasons, therefore, the development of student management system is also a necessary step in the era.

This research is aimed at building a real time public fitness service system, with massive data storage and processing ability, to meet the public fitness service demand. In this research, we focus on the system positioning, cloud delegation model, service model, service content and operation mechanism of the fitness service system. Method used was system analysis method.

The flight mechanism of flapping-wing was studied by using the translation-rotation model. We established the flapping-coordinate of the wing, gave the equation of the motion, and simplified the flapping-wing model. The aerodynamic and vortices were simulated by the CFD software of Fluent. The leading-edge vortex generated in the translation phase, and delayed stall mechanism had an important effect on the high lift. In the rotation phase, lift peaks appear due to the wing rapidly rotating and rotational circulation mechanism. The aerodynamics were obtained in different amplitudes, frequencies, angles of attack, the locations of rotating axis and timings of rotation. The influence of these parameters on average lift coefficient is obvious, while it can be ignored to average drag coefficient. Keywords: wing, aerodynamics, vortices, numerical simulation.

In this paper, an activator protein was isolated and identified from crude protein of Botrytis Spp which was separated from the soil of the wheat field with the method of mycelium recycling, breaking and centrifuging,etc. The activator protein appeared a single band on SDS-PAGE whose molecular weight was about 42kD. At the same time, it had a preliminary activity test and investigated on this activator protein. This study indicated that this activator protein is able to promote wheat germination after the deal with it, especially when the density is 3μg/mL, the seed germination is the best. So it is proved that the plant activator protein has really the biological function of improving the wheat germination.

High temperature was an restrictive factor for tree peony growth and distribution in the world. In this study, we identified a heat shock transcriptor PsHsfB1 from our tree peony gene database. Further analysis revealed that the PsHsfB1 was sequence conserved and closely to Hsfs in others plant species. Gene Ontology annotation revealed that the PsHsfB1 was correlated with theromotolorance of tree peony.

The dynamic performance of the 12m span prestressed concrete beam is analyzed by finite element method. Based on the finite element analysis, with the change of the peak dynamic load, the risetime of dynamic load and the reinforcement ratio of prestressed reinforcement, the change laws of mid-span maximum deflection and the maximum stress of prestressed reinforcement in prestressed concrete beam are studied. At the same time, have further understanding to the stress and deformation of the prestressed concrete beam under explosive load. It can provide references for study on dynamic performance of the prestressed concrete beam under explosive load.

The paper is concerned with 1-MCP effect on post-harvest Pleurotus eryngii weight loss rate, polyphenol oxidase (PPO) activity and fruit body microstructure at different storage stage.The results showed that compared with control group, the weight loss rate and PPO activity were decreased by 5.94% and 37.38% ,and its microstructure had least change after 14d when treated with 0.3µL/L 1-MCP.The weight loss rate and PPO activity also decreased by 5.42% and 33.98% respectively with least change in fruit body microstructure after 14d when treated with 1-MCP for 24h. It proved that the optimal 1-MCP processing concentration is 0.3µL/L and the most appropriate processing time is 24h. These processing conditions slowed down the weight loss rate and browning level ,also reduced the change of fruit bodies microstructure and extended storage period

Xindao-18(Oryza sativa L. subsp. japonica Kato) were irratiated with a low-energy ion-beam, the growth form were observed and transcriptome of samples were sequenced by Illumina HiSeq2000 platform. The different expression genes were identified from transcriptomes control and treated samples. Finally, the coexpression of different gene expression were construce and seventy DEGs were annotated as transcription factor (TF). Among them, ten transcripts have the higher network density, and two genes, LOC_Os06g15330 and LOC_Os03g51970, had a still higher network density while elevate PCC paramater, which indicated that the indentified coexpression transcriptors may play important role in response to N+ ion beam treation.

Wireless sensor networks (WSNs) is taking an increasing role in our lives. Because the energy of the sensors is limited how to efficiently use the energy to prolong the lifecycle of the sensor networks is very important. In this paper, a novel energy-balanced dynamic routing algorithm based on ACO is proposed. The novel routing algorithm can dynamically choose routing according to the residual energy of the sensors and the sensors with more power is taken more data transfer tasks. The simulation results show that the proposed routing algorithm can effectively balance energy consumption and prolong the lifecycle of the networks.

Based on the analysis of setting principles of tidal lane, this paper describes the traffic and technical feasibility on setting tidal lane aat Xizhimen Outer Street between Chedaogou Bridge and Sijiqing Bridge, and then put forward a package on setting of tidal lane and control approaches of segment and endpoint. Through an analysis of the package, we expect to relieving road network pressure from tidal traffic and achieving the purpose of easing traffic congestion.

In this paper, we study the strict practical stability for the discrete hybrid systems in terms of two measures. Using Lyapunov-like functions, we obtain some comparison theorems first and then by them get a sufficient condition on the strict practical stability of the hybrid system.

Based on the principle and characteristics of cloud computing, we put forward the detailed introduction of the constitution and function of cloud information resource flow architecture. Therefore, the problems of network source information management, supervisory control, exploitation and utilization can be solved.

security objectives, and the commonly used Mobile Ad hoc networks security protection technology, and finally discusses the application of mobile Ad hoc network in the field, and their security policy are analyzed.

In multi-level security database system, the inference problem is that a low security level user using accessible data and his own knowledge and to infer confidential information of higher security level, which constitute an attack on the database. This paper introduces a formal description of multi-level secure database systems inference channels and analyzes several common inference channels and its solution.

This article analyzes the network introduced in the fitness advantages of cloud computing technology based on the construction of the current status of network resources, services, fitness and mechanism. And fitness areas of the network cloud application prospects are also discussed.

Dismantling the inner support of deep foundation pit is a risk point.It is of great importance to guarantee the safety of foundation pit when removing the inner support, and the deformation monitoring and analysis in the process of dismantling inner support is crucial. In this paper, a super deep foundation pit engineering as the research background.Through monitoring and analyzing the law of a deep horizontal displacement of the supporting structure,ground settlement, vertical settlement and axial force of support in the process of support demolition,which can be obtained that: the settlement of surface ground around the foundation shows spatial and temporal clearly and the distribution of deep horizontal displacement of supporting structure is similar to the parabolic which the maximum point constant upward shift with supporting continuous removed.Soil pressure of supporting shared with support removing process is changing, and the earth pressures support sharing is increasing. From the monitoring results, the demolition scheme is reasonable and effective and meets the requirements of design and environment.

As an example of collapsible loess foundation treatment project in central and southern shanxi tunnels five railway culvert, the collapsible loess and harm of engineering properties, this paper introduces the construction method by cement-soil compaction pile to reinforce the foundation in order to ensure the quality and effect of the overloaded railway foundation.

The preparation of magnetite nanoparticles with controlled size has attracted of scientific and technological broad attention. Spherical magnetite nanoparticles in the size range from 8nm to 22 nm were synthesized by coprecipiation method using hexadecyl trimethyl ammonium bromide (CTAB) as dispersant. Magnetite nanoparticles have good dispersibility and uniform particles size distribution. The properties were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), automated surface area and pore size analyzer, vibrating sample magnetometer (VSM) and the catalytic performance was measured using high performance liquid chromatography (HPLC). The saturation magnetization is 13.785emu/g, and the coercive force of the sample is 23.738G, the average size of the particles is 13.6 nm, specific surface area is 19.318 m2/g and phenol conversion is up to 99.5%. These results indicate the synthesized magnetite particles have good performance.

With the increase of high-rise buildings, people rely on high-rise buildings are also increasing. But, there is a problem that is fire safety of high-rise. In this paper, we research on storage water of fire pool for high-rise building and make a summary of water output about the fire pool. As a guide to regulate and combined with the existing problems, we should consider arrangement of fire pool and strengthen municipal planning. We will discuss storage water of fire pool for high-rise building.

Aimed at engineering problems lied in inshore saline soil in the northern part of China, the store environment is analysed, and the relation between the salinity and the engineering property index is studied. The result shows that the plasticity index and the compression coefficient of the northern inshore saline soil reduce with the increase of the salt content, and the shear strength attains a limit value with the increase of the salt content.

Precast two-way hollow slab concrete shear wall is a new structure adapted to housing industrialization. To study the effect of the vertical joint on mechanical behaviors of shear walls, one reinforced concrete shear wall and two precast concrete shear walls built with hollow slabs were quasi-statically tested under low cyclic loading. The study of failure mode and failure process of specimens shows that vertical macro-cracks occurred in precast walls under loading, which made failure behavior of walls evolve from integral wall into split wall. It also shows that relative deformation formed along the vertical joint before peak load, so the ductility of walls is increased. New type shear walls exhibit good ductility and brittle shear failure can be avoided effectively.

Level test method is widely used to detect concrete crack depth. Accuracy of the methods is determined by measurement of concrete velocity and transit time. Some proposals are presented to improve accuracy of the test in terms of on-site testing methods as well as crack direction besides judgment of initial wave and role of steel reinforcement nearby. It proves well by way of project example.

This paper designs the virtual online platform of high precision machinery processing. And we use it to forecast the safety coefficient k and lift coefficient of auto machining process, and based on the safety coefficient and the lift coefficient we improve the automobile working procedure real-time, and obtain a reasonable body safety structure and external driving performance of the structure, which achieves good comprehensive design effect. At the end of this paper, we apply the system in the online virtual platform of computer higher occupation education. According to the cycle mechanism of the lift coefficient, we design the teaching task of cultivating innovative talents, and arrange the teaching tasks of applied science. It provides the theory reference for research on the higher occupation school personnel training.

The technique of plasma polymerization was used in the preparation of the poly (cyanate ester) thin films using 4-methoxyphenol cyanate ester (MPCE), 4-Cumylphenol cyanate ester (CPCE) and 4-phenylphenol cyanate ester (PPCE) as precursors. Different from the conventional thermal polymerization of cyanate ester monomers, the plasma polymerization of three monomers proceeds mainly via the opening of π-bonds of the cyanate ester functional groups which are further formed into a large π-conjugated system. The dielectric properties of the resulting plasma thin films were evaluated and results show that the dielectric constant of the three polycyanurate thin films decreased with increasing frequency, while in contrast, the dielectric loss factor increased with the increasing frequency. The obtained poly (cyanate ester) thin films might be the potential new candidates to be used as intermetallic dielectrics in microelectronics.

An realization of EEG application platform is displayed in this article. EEG signals are gathered and processed by Head-mounted device to obtain control use parameters, which is to be transmitted to the PC platform or the single-chip control system through Bluetooth. The software on the PC platform could make use of the control use parameters, while the single control system could output instructions to control the connected hardware, according to the computation results of the parameters.

In order to reveal the effect of drying temperature on quality of purple sweet potato powder, four drying temperatures (70, 80, 90 and 100 oC) were selected. The effect of color, anthocyanin content, and scavenging ABTS free radical ability were studied. The results showed that drying process decreased anthocyanin content, and with increasing drying temperature, the a* value and anthocyanin content decreased. However, the treatments dried at 80, 90 oC exhibited the similar scavenging ABTS free radical ability with control, while the treatments dried at 70, 100 oC had lower scavenging ability than control.

In order to achieve comprehensive vehicle fuel economy, dynamic performance and safety, a novel hydraulic hybrid vehicle with supervisory control system is proposed. The hierarchical structure control system integrates driving intention recognition, power distribution, regenerative braking intensity regulation and temperature monitoring modules. The high speed CAN bus is used to communicate for different modules in the supervisory control system. Supervisory control system recognizes the driver’s intention and the vehicle status through the feedback signals of sensor system, and reasonably distributes power output of all power sources. Finally, the experimental efforts have been performed to assess the performance for the proposed supervisory control system.

This paper introduces one ultrasonic distance measurement device based on single chip processor and mainly describes its hardware circuit and software design. The ultrasonic distance measurement device has many merits such as simple structure, low-cost, high-accuracy, microminiaturization, digital display and so on; this result reaches the expected target. The practice result shows that the ultrasonic telemeter has very high generalizing value.

At present, artificial bait casting and water quality detection are widely used in the domestic aquaculture, it is difficult to improve the yield and quality of the output of aquatic products such as fish, prawn and crab because of low production efficiency and limited labor force. This paper proposed an automatic aquaculture workboat driven by air propellers based on 3G(GNSS、GIS、GPRS), equipped with main controller ARM11, automatic path planning and tracking based on GIS and GNSS system and remote monitoring with GPRS communication module, the workboat can perform bait casting and water quality parameters detection such as dissolved oxygen, pH, water temperature, ammonia nitrogen and salinity automatically according to the aquaculture tasks. It can improve the aquaculture work efficiency and save the manpower and the material resources.

It is of great significance for screw-propelled vehicles to solve the problem of driving on the soft ground. In this paper, the development of screw-propelled vehicles both at home and abroad is reviewed; the domestic and foreign propulsion theory research results of scholars are summarized based on terramechanics; the deficiency of the modern research methods is analyzed. At last, some discussions on study methods are made in particular.

In order to overcome the shortcomings of the present accuracy assessment methods of power system dynamic simulation, this paper focuses the permanent single phase short-circuit fault which occurs in a large probability in power grids,and selects the typical electrical quantities which is very concerned in engineering after the fault happened. A time-scale based error criteria on simulation validation is proposed, and a comprehensive error criteria according to the average errors between simulation data and actual data is proposed to evaluate objectively the simulation accuracy of the typical electrical quantities. Considering the variation characteristics of the electrical quantities, the simulation accuracy evaluation of a single electrical element is expended to the simulation accuracy evaluation of the entire network, so not only the comprehensive evaluation about the model and its parameters but also the information for model modification and parameter correction can be obtained. The effectiveness of the proposed method is verified by the numerical results on the New England 10 Unit 39 Bus powers system.

According to the technical requirements of controlled fire extinguisher filling pretreatment of self-propelled artillery, in this paper, we use the method of principles tunnel to control the air flow, combined with multi-parameter self-tuning fuzzy PID control, different models of controlled fire bottle filling pretreated at the same time are achieved, and the adaptive capacity of controlled fire extinguishers pretreatment equipment is improved. After the trial, the device has high synthesis, good versatility and high stability.

This first step of ageing management in nuclear power plant is to determine the objectives and their priorities. The characteristics of the objectives are complex and highly nonlinear coupling. A fuzzy logic based screening and grading method have been developed in this research for the first time which combined the genetic ageing lessons learned and field expert experience to resolve the problem. The method have been approved of highly applicability and applied to ageing management in multiple nuclear power plants.