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For DC circuit breaker has not been applied in UHVDC project, the fast-isolating switches are used to isolate faults of the converter station or transmission line in the multi-terminal UHVDC transmission system. New problems which are not existed in two-terminal HVDC system and DC power grid but faced by the multi-terminal UHVDC transmission system are analyzed. Especially, the fault clear problems of pole protection action, valve protection action, DC line fault restart, metallic line fault restart and pole balance. On the basis of those analysis, fault clear strategies to solve these problems are put forward exploringly.

Because of the lack of single test methods for DC protection system in converter station, this paper firstly analyzes the difference between DC protection system and relay protection device in substation, and explains that DC protection system has its own characteristics and cannot copy the whole way of relay protection device. On the base of the detailed analysis of the development history and standard evolution of the control and protection system of substation and converter station, a general test architecture scheme is proposed, which can be used for the single test of DC protection system on the premise of making full use of the existing relay protection tester, that is, the way of adding the specification conversion device in the middle. At the same time, based on analyzing the characteristics of various standard protocols, IEC 60044-8 is selected as the communication protocol between the tester and the protocol conversion device. Based on this architecture and protocol, the single test of the DC protection system is realized.

Background: Bone loss induced by microgravity is a serious problem in space flight. However, the effects of acupuncture stimulation on osteoporosis induced by microgravity have not been studied. With the goal of developing an effective countermeasure, our aim was to evaluate the effects of electroacupuncture (EA) stimulation at BL20, BL23, and SP6 on osteoporosis induced by simulated microgravity in rats. Methods: Thirty male Wistar rats (aged 10 weeks) were randomly divided into three groups: healthy control group (CON, n = 10), hind limb unloading by tail-suspension group (T-S, n = 10), and EA treatment group (TRE, n = 10). Rats in the T-S and TRE groups were subjected to tail-suspension at −30° for 30 days, while the CON group experienced freedom of activity. In this period, the TRE group received EA treatment at BL20, BL23, and SP6 for 30 min every other day, which continued for 30 days. The microarchitecture of the proximal tibia and the biomechanical features of the femur in the rats were analyzed. In addition, the levels of serum biomarkers bone alkaline phosphatase (BALP) and osteocalcin (BGP) were measured. Results: Compared with the CON group, the value of bone volume/total volume (BV/TV) and trabecular number (Tb.N) of the tibias in the TRE group remarkably decreased ( p Conclusions: These findings indicate that EA stimulation at BL20, BL23, and SP6 retards osteoporosis induced by hind limb unloading in rats.

This paper reports the use of tunable diode laser absorption spectroscopy (TDLAS) to measure the carbon dioxide (CO2) in the culture vials. The accumulated CO2 concentration in the headspace is linked with the growth of the microorganisms cultured in the vials. The 2004.1 nm spectral line of CO2 is selected as the sensing transition for its strong absorption strength. The proposed TDLAS sensor is calibrated and verified with several CO2 standard gases, yielding a minimum 1σ detection limit of 0.084% with an integral time of 3 s. The suitability of the sensor to the microorganisms is performed, almost the results agree with the growth laws of microbiology. Since the sensor is fast and nondestructive, it can be promising for in-line detection of microbial growth.

This paper analyzes the function of each subsystem under the overall framework of intelligent building, and puts forward an intelligent building design system based on BIM and artificial intelligence. The system is divided into data layer, model layer and application layer. It uses engineering feature modeling, engineering structure model decomposition, machine learning and other methods to establish a parametric construction project information management model. Then the function and application process of optimization control, dynamic construction management and dynamic construction simulation are optimized. According to the BIM system platform, the information interaction access rights of all participants in the project are determined. Finally, the scheme and implementation promotion strategy are applied to the specific pilot project. The results show that the system can directly reduce the workload and difficulty of intelligent design, and improve the design efficiency and quality.

This paper analyzes the optimization design process and implementation method of green building scheme stage based on BIM Technology. From the perspective of BIM Technology, the integrated design mode of green building is proposed, according to its characteristics of visualization, coordination, simulation and optimization risk. In the decision-making model design of building scheme, three objective functions are established from three aspects of building energy consumption, natural lighting and natural ventilation. Then, by combining BIM Technology and Bayesian network, a comprehensive evaluation optimization model is constructed. Through the knowledge component and item evaluation of the above evaluation criteria, the system framework, the system function module and system workflow are determined. At last, we use software engineering related ideas and a variety of software development tools to complete the development of Revit end compliance check plug-in and web end information interaction platform, as well as the application and evaluation of related engineering cases.

In this paper, the energy-saving technology of prefabricated concrete building envelope is studied. To further understand the thermal performance of the exterior envelope of the prefabricated building, the typical common house type is used as an example of Ecotect simulation, and the thermal parameters of its envelope structure and each component are determined. The current envelope structure and specified indexes of the structure type are compared, and the energy consumption is compared in the simulation calculation. At the same time, based on the conclusion of numerical simulation, the overall energy-saving optimization scheme of prefabricated buildings is determined, and the energy consumption of prefabricated houses is compared with the original ones by DeST -h and other softwares. Then the energy-saving efficiency after optimization is analyzed, and the energy-saving strategy after optimization of the outer envelope structure of prefabricated buildings in a certain area is obtained.

The Chinese space station will be built around 2020. As a national space laboratory, it will offer unique opportunities for studying the physiological effects of weightlessness and the efficacy of the countermeasures against such effects. In this paper, we described the development of countermeasure systems in the Chinese space program. To emphasize the need of the Chinese space program to implement its own program for developing countermeasures, we reviewed the literature on the negative physiological effects of weightlessness, the challenges of completing missions, the development of countermeasure devices, the establishment of countermeasure programs, and the efficacy of the countermeasure techniques in American and Russian manned spaceflights. In addition, a brief overview was provided on the Chinese research and development on countermeasures to discuss the current status and goals of the development of countermeasures against physiological problems associated with weightlessness.

As unconventional tight oil reservoirs are currently a superior focus on exploration and exploitation throughout the world, studies on production performance analysis of tight oil reservoirs appear to be meaningful. In this paper, on the basis of modern production analysis, a method to estimate dynamic reserve (OOIPSRV) for an individual multistage fractured horizontal well (MFHW) in tight oil reservoir has been proposed. A model using microseismic data has been developed to calculate fracturing network parameters: storativity (ω) and transmissivity ratio (λ). There main focuses of this study are in two aspects: (1) find out effective methods to estimate OOIPSRV for an individual MFHW in tight oil reservoir when there is only production data available and (2) study the relationship between productivity and fracturing network parameters (ω and λ) so as to estimate the productivity for individual MFHW from microseismic data. In order to demonstrate and verify the feasibility of developed methods and models, 5 filed wells and 2 simulated wells have been analyzed. The proposed method to calculate OOIPSRV proves to be applicable for MFHW in tight oil reservoirs. From the calculated results of ω and λ for example wells, it has been found that there exists linear relationship between the value of ω/λ and average production (Q ave) for an individual MFHW completed in this actual tight oil reservoir. On the basis of derived linear relationship between ω/λ and Q ave, the productivity for more individual MFHWs can be directly estimated according to microseismic interpretation.

The fault of electrode line can pose serious threat to the safe and stable operation of the High Voltage Direct Current (HVDC) system, but it is quite difficult to detect the line fault by normal ways because the grounding electrode line is usually at ground potential. This paper presents a novel fault monitoring and location system for HVDC electrode line, which is based on the TDR technique and specially designed according to the characteristics of electrode line. The system injects differential mode voltage pulse to monitor the electrode line, and reduces the cancellation of differential mode signal through series reactance. Theoretically, this system is immune to the interference signal from the HVDC system, and can greatly improve the Signal-to-Noise Ratio (SNR) of the reflected pulse. In addition, the system uses a waveform comparison algorithm to solve the problem of line parameter uniform and slowly changing, which could make much trouble to the normal TDR methods. For this fault monitoring and location system, the output pulse amplitude is designed as up to 500 V, the pulse width range is about 1-5 $\mu$s, and the pulse sampling rate is as high as 10 MHz. Simulation results and field applications show that this system can achieve excellent fault monitoring and location result for the HVDC electrode line, with the fault location accuracy better than 300m.

Recently serverless cloud computing which was proposed by Amazon in 2015 is getting more favored by developers because of its charging model of pay-by-usage, applicability for fine-grained services and transparency of the servers to developers. Although a lot of study has proved that the performance and cost of serverless platform is more ideal than the traditional cloud computing service, the new metering model of serverless which depends on execution time, usage count and memory footprint is still unfamiliar to most developers and researchers. In this paper, we firstly make an introduction to the new metering model and the advantages of serverless over traditional cloud services. Then according to the cost affecting factors, we make a comprehensive survey of some constraints that mainly impact the cost of serverless and related methods to reduce cost in three levels—function level, container level and cloud platform level. Based on the analysis, we also propose some directions worthy of in-depth study in the future.

Fault diagnosis of HV circuit break has been investigated extensively as an important device in the field of power system. In view of the shortcoming of the traditional neural network, such as the slow convergence rate and the lo- cal minimum easy to form, fault diagnosis method of HV circuit breaker is proposed to remedy the defects of traditional neural network based on wavelets neural. This method adopts wavelets function rather than the hidden nodes of traditional neural network, which is propitious to conducive to achieve a rapid convergence of online learning. This work firstly dis- cussed the principles of fault diagnosis method in detail, and then compared diagnosis effect using wavelets function with that of the traditional neural network. The results show that the training speed and classification effect of wavelets neural network are superior obviously to those of traditional neural network. Wavelets neural network based on vibration signals is more suitable in application to the fault diagnosis of HV circuit breakers.

A new method that researching fault diagnosis of high-voltage (HV) circuit breaker (CB) is proposed. The method combines Wavelet Packet (WP) with Radical Basis Function (RBF) Neural Network (NN). Firstly, by applying the theory of WP decomposition and reconstruction, the mechanical vibration signal of CB was decomposed into different frequency bands, and the coefficients are reconstructed in the corresponding node. After that, the feature vector was ex- tracted by equal-energy segment entropy from reconstructed signals. Finally, fault diagnosis has been realized through the classification of feature parameters combined with RBF neural network. The experiment outputs show that the method can be applied in diagnosis.

Fuzzy tracking control discuss the pure model behavior and ignore the original mathematical model, make the picking robot arm gain accurate perception ability to complex environmental condition, control its velocity and reach smoothly the target position. This paper proposed fuzzy tracking controller algorithm for obtaining the joints position relative to the desired trajectory, which drive stably 3 joints tending to be stable in 1.5s on the conditions of changeable environment, reflecting the strong robustness and stability of the tracking control system, enhancing their positioning and grasping stability to restrain picking robot arm chattering.

In VANETs, information exchange plays an important role to make vehicles aware to each other and provide references for safety or non-safety related applications. At intersections, vehicles are forced to maintain a lower mobility thereby have more time to exchange on-road or off-road context information. However, if an effective control scheme is not applied to this specific scenario, a packet congestion is more likely occurring especially when the vehicle density is high and channel load is heavy. In this paper, to solve the aforementioned problem, a congestion control scheme based on non-cooperative bargaining game is proposed. Numerical results show that our proposed Joint Power and Rate Adjustment congestion control scheme (JPRA) can greatly alleviate the possible packets collisions thus reducing the average experienced delay in queue and increasing the number of successfully delivered packets on the receiver side.

During the operation process of the high voltage circuit breaker, the changes of vibration signals reflect the machinery states of the circuit breaker. The extraction of the vibration signal feature will directly influence the accuracy and practicability of fault diagnosis. This paper presents an extraction method based on ensemble empirical mode decomposition (EEMD) and correlation dimension. Firstly, original vibration signals are decomposed into a finite number of stationary intrinsic mode functions (IMFs). Secondly, calculate the correlation dimension of the top four IMF by the G-P algorithm. At last, calculate the root mean square value of the four correlation dimensions to be as the characteristic of vibration signal for HV circuit breaker. Practical examples show that the characteristics through the extraction approach put forward can represent effectively fault patterns of HV circuit breaker.

An optical fiber waist-enlarged bitaper-based Michelson interferometric sensor is proposed and experimentally demonstrated for humidity measurement. The waist enlarged bitaper is created for light coupling between core mode and cladding modes propagating in the fiber interferometer. A chitason layer is plated onto the surface of the interferometer to act as a humidity-to-refractive index (RI) transducer and thus humidity measurement can be realized by monitoring the wavelength shifts of its interferogram induced by RI variations. The influence of the coating thickness and concentration of chitason on relative humidity (RH) measurement is experimentally studied. The coating sensor demonstrates an optimal humidity-sensing ability, with a humidity sensitivity and fast time-response of ~26 pm/%RH and ~5 s respectively, when it is 3-dip coated in chitason solutions of the concentration of 1 wt.%. The proposed humidity sensor is compact, cost-effective and of easy-operation, therefore it has potentials in many practical applications.

A method of guidance and control for automatic landing of flying-wing unmanned aerial vehicle (UAV) is proposed in this paper. Based on wind tunnel data of a flying-wing aircraft, small disturbance equations of the flying-wing aircraft is built using MATLAB. With the help of the model, automatic landing plan and control law is designed. Simulation and analysis are finished based on non-linear equations. The final simulation results show that the guidance and control law can meet the requirements of automatic landing of UAV, and has excellent static and dynamic performances.

Based on the standard FA easily traps in a local optimum, this paper presents a method that the current particle choose the one in its visual field which has the best fitness as the global best particle. The experiment shows the advantaged algorithm has a better global search ability. The paper uses the advantaged FA into the group animation, the particle has good artificial intelligence performance, and can simulate group behavior in an actual way.

Through the analysis of flowers pattern, firstly this paper abstracts the needed patterns and uses the genetic algorithm to generate new pattern so as to found a colorful pattern. And then through the analysis of the flowers pattern, it selects and assembles the various patterns automatically to create lots of different styles of the art patterns which can also be manually changed according to the actual needs. The above method has been proved in the experiment that it can enhance the creativity of the flowers pattern designer.

Vehicle monitoring technology based on the video image due to its features of easy maintenance and easy implement is concerned in recent years. Vehicle tracking is one of the key technologies to achieve video vehicle monitoring. How to achieve real-time vehicle tracking is the key and difficult problem at home and abroad. A method of Kalman tracking based on virtual loop is proposed in the paper. Two parts about vehicle presence detection and vehicle forecast tracking are introduced in this paper. Experimental results show that this method in the fast-path scenarios can effectively achieve vehicles tracking, fully meet the system requirements and have high practicality.

Based on PLC, this paper blends the automatic control theory with the feed processing industry and carries out design and research on the feed production automatic control system. Mainly employing the method of combining the upper computer with the PLC, this system can collect, recognize and control data to progressively implement the automatic control of feed production process. VC and configuration software are generally used to program for the system of which the database adopts SQL Server2000 and the PLC resorts to ladder diagrams to design software programming. The running result shows that this system can detect and control safety parameters and achieve the automatic technology transform of feed production lines.

On the basis of established switch object model, this paper presents a hard configuration and a soft configuration of the CAN field bus intelligent communication node based on P87C591, and describes the design of software initialization of CAN controller, as well as sending and receiving process of CAN nodes. A distributed testing system has been built and CAN protocol specification compatibility of this communication node has been verified finally.

In this paper we report on WDM transmission of optical labeled signals using the orthogonal IM/FSK modulation format aimed for optical packet/burst switching. WDM transmission in both a point-to-point transmission system and a demonstration network with a label-swapping node are implemented.

We have presented a complete and thorough experimental study of supercontinuum (SC) evolution processing in dispersion shifted fiber (DSF). When the pump power is relatively low, the SC spectrum is asymmetrically broadened toward the zero dispersion wavelength of DSF due to self-phase modulation and group velocity dispersion. When the broadened spectrum spans the zero dispersion wavelength, cross-phase modulation and four-wave mixing cause symmetrical spectrum broadening. Stimulated Raman scattering causes the spectrum to broaden toward the long wavelength quickly when pump power is intense enough.

Gain-switched DFB lasers are widely used to generate short optical pulses for soliton transmission, optical time division multiplexed communication and optical signal processing. However, they are more susceptible to timing jitter than gain-switched F-P DFB lasers. The pulse to pulse time jitter will transfer to the relative intensity noise (RIN) and seriously degrade the bit error rate performance of optical switching controlled by control and signal pulses, such as nonlinear optical loop mirror and semiconductor laser amplifier in an optical loop mirror. Techniques for addressing this problem include external continuous wave (CW) light injection and self-seeding. CW light injection needs an additional CW light source and its wavelength should be selected to match the wavelength of the injected pulse source. We present a novel method to reduce timing jitter in a gain-switched DFB laser with a fiber loop mirror (FLM) containing a polarization controller (PC) and a fiber stretcher. Self-seeding injection is to use a portion of output pulse power, so that seeding injection power and appropriate delay time will play important roles for stabilizing the spontaneous emission fluctuations to obtain short optical pulses with low time jitter. We examine these effects experimentally and show dramatic timing jitter reduction from 5.7 ps to 1.2 ps.

An important aspect in the development of communication networks is the development of signalling technology. SS7 is a common channel signalling system recommended by CCITT, which is adapted to the development of ISDN and IN. This paper presents a general scheme to implement SS7 in JSU-16000, a fully distributed control digital switching system, that is developed by ourselves.

A 10 GHz all-optical switch based on an ultrafast nonlinear interferometer (UNI) was demonstrated and an extinction ratio of 11 dB was obtained. The UNI is composed of a traditional single-arm interferometer (SAI) and a semiconductor laser amplifier (SLA), which is used as a nonlinear component. By virtue of the structure of the SAI, long-lived refractive index nonlinearities do not affect the achievable data.

Employing a polarization flag in a frame, we construct a point-to-point optical time division multiplexing (OTDM) communication system with a simple and feasible structure. In this system the frame clock is successfully extracted with an all optical method.