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To solve the wide range of the output voltage, difficult storage and not unified interface of solar cell, a novel solar charging system was proposed. The system consists of the solar panel, the voltage regulator circuit, the battery charge management circuit, the lithium battery, the booster circuit and the USB output circuit. The voltage regulator circuit can convert the output voltage of solar panel into 5V. By means of the charge management circuit, the energy is stored in the lithium battery, and it can be provided to the load via the booster circuit and USB interface, which can achieve the goal of the conversion, storage and utilization from solar to electrical energy. Under the condition of effective illumination between 10:00 and 16:00, the solar charging system was tested for 7 days. Experimental results show that the output voltage always maintained at 5V during the test. The output voltage of lithium battery reaches to 4.2V after four hours, and the output voltage of USB port always stabilizes at about 5V.

In order to achieve the wireless operation of the data collected and system monitoring in the weighing equipment, a wireless weighing system design was proposed. This scheme combines with the weighing control technology and the wireless communications technology. The weighing system includes the pressure sensor, the signal processing module, the microprocessors, wireless data transceiver module, the infrared module, the memory module, the display module and the control module. Based on the experiment of ten different targets ranged from 5kg to 50kg, the wireless weighing system was measured and analyzed. Experimental results show that the maximum error rate of the wireless weighing system is 0.2%, and wireless transmission distance reaches two hundred meters.

According to the original design, the strength of the web should be able to withstand the support reaction force during launching. While in the process of pushing construction, local buckling of the web on the support occurred. In view of the above situation, in this paper, establishing solid models for finite element analysis based on the ABAQUS software, comparing with the result of original design, and it was found that there existed some differences between simplified model and constraint condition of the design and construction. That is, the original design did not consider the deformation cased by beam segments arching, which caused the bearing area reducing and stress concentration, this was unable for the design software based on beam elements method to analyze. This problem could be solved by elevating the arching supporting. The analysis showed that elevating the adjacent supporting could reduce the maximum stress in the structure effectively by sharing the loads.

The aperiodic impulse voltage generator is huge and difficult to move in field, thereby limits its application in field significantly. For this problem, the oscillating impulse voltage (OIV) is recommended in standard IEC60060-3. In order to study the influence factor of oscillating impulse voltage generator, the simulation circuit is set up using ATP software. The influence of parameters such as shaping resistors, load capacitance and shaping inductance are study in this paper.

Once the GIS appears screws loose and other phenomena, it will lead to the generation of floating potential, then trigger the floating potential discharge. In order to study the discharge characteristics of the floating potential, this paper artificially built floating potential defects on the GIS malfunction simulation platform, and detected with ultrasound and UHF methods. The results show that once the floating potential discharged, it would produce a larger amplitude signal. And the discharge most concentrated between the zero crossing and the peak point among the entire phase range. Ultrasound and UHF detection has obvious signal.

In order to accurately analyze the field test results of the partial discharge in GIS and study on the partial discharge characteristics of typical insulation defects in GIS, this paper constructs a set of failure simulation test system which is based on the entity 363kV GIS which contains all the Main equipments. These system has artificial defect setting units and can applied voltage and current at the same time, it also can manually set a variety of GIS typical insulation defects at the defect setting units. The partial discharge detection and analysis in the case of the applied voltage and current can simulate actual field operating conditions of GIS.

Gas insulated switchgear (GIS) will generate vibration during normal operation for the electromagnetic force. There will be generate abnormal vibration when the contacts are undesirable, the guide rod stressed unevenness. Therefore, it can be effective in fault diagnosis of this machineries through the vibration test of GIS in field. The vibration detection method of GIS equipment in field is studied in this paper, the composition of the vibration detection system is described. The field test has been done using vibration detection system and the test results show that through the vibration signal detected from the GIS equipment, the vibration characteristics of GIS can be clarified and make the fault diagnosis effectively.

Gas insulated switchgear (GIS) is the most important equipment in the power system. The partial discharge (PD) is the main detection method for the insulation failure. Especially, for insulation condition assessment, the pattern recognition technology of partial discharge in GIS is the most important. Acoustic detection of GIS PD is the effective method and it has long application history. The acoustic detection method is very suitable for defects detection in GIS, for it has the advantages of on-line detection and easy realization of locating the defects.The PD pattern characteristic is the key factor for the analysis of defect type. The PD pattern characteristics of four typical defects in GIS based on acoustic detection are studied in this paper. The results provide a test basis for the recognition of PD types and a deeper study of the mechanism of PD.

Lightning current is very important parameter for evaluating the overvoltage of the power system and characterizing the electromagnetic compatibility of the electronic equipments. Therefore, it is indispensable to measure lighting current by a suitable sensor. This paper presents a self-integrating rogowski coil for lightning current sensor, and introduces the operating principle and analyses characteristics of it. In addition, to improve the precision of the sensor this paper proposes design procedure of the phase compensation method and the circuit structure to implement the phase compensation method. The simulation results verify that the phase compensation method can enhance the precision of the self-integrating rogowski coil.

According to IEC60060-1, IEC60060-2 requirements, on-site tests for the high voltage apparatus can not be achieved due to many external factors such as the huge impulse voltage source and external electrical and magnetic fields, weather condition, etc. Therefore, IEC60060-3 points out the impulse waveforms for the high voltage apparatus during on-site tests, one of the impulse waveforms is the oscillating switching impulse, but the oscillating switching impulse source with high amplitude is a bulky test equipment which is not suitable for the on-site test, consequently the demands for portable oscillating switching impulse source is urgent. This paper presents that the high oscillating switching impulse voltage can be generated by a low oscillating switching impulse voltage with the power transformer which is the test object, the simulation and experiment results show this method can be used for the power transformer during oscillating switching impulse on-site test.

Slide gates are installed at the bottom of a ladle or tundish to control the flow of molten steel. It plays an important role in ladle refining process and continuous casting. Al2O3-ZrO2-C refractories are widely used as slide gate materials due to its excellent corrosion and thermal shock resistance. At the start of casting, molten steel almost 1600°C passes through the bore of slide gate, the plate is rapidly heated up, the temperature difference between the bore and edge part, the slide gates are subject to large thermal gradients, so there is large thermal stress in the plate. This paper will show the results of our improved slide gates with good thermal shock resistance.

Nowadays online quality estimation for the resistance spot welding (RSW) has benefited a lot from monitoring the electrode displacement caused by nugget thermal expansion. Based on these emerging monitoring techniques a new approach is proposed to classify the weld quality and assure the quality for mass-produced weld group, which enables the continuous quality improvement concept during the welding process. A causal models are built with the offline trained Bayesian Belief Networks (BBN). It is a weld quality assessment net reveals the dependency of the weld quality on the features displayed by the displacement curve, which can be used for overdesigning the safety welds or as the probabilistic forecasting model for online weld quality assessment. The experimental results show that the proposed approach is valid and feasible to predict the weld quality and assure the overall quality for weld group in real applications.

RT（X-Radiography Testing） is a very import inspection method for detecting engine blade crack, and the defect is identified by person distinguishing the film for traditional RT. The traditional method is involved in high mistake and missed examining rate and low efficiency. It is great significance to blade integrity and flight safety that the crack can be quickly distinguished. In the paper, adopting a adaptive segmenting algorithm based on OTSU to quickly distinguish the crack on the blade image, and it can definite the threshold facing different gray image, and can reliably inspect the cracks which detection rate was 98%. The recognition accuracy for crack can reach 0.16mm Simulation result verify that the method is very effective on adaptively segmenting the blade image according to the threshold for crack inspection

The positioning accuracy can bring a great impact on inspecting defect for Aero-engine blade. The high or low pressure rotor of engine is generally driven by manual when blade’s defect is inspected. Frequently，False detection and missed happens due to match failure between two persons. Adopting a high-resolution, high-accuracy algorithm based on FPGA to design automotive equipment for high or low rotor . The Frequency range to step motor is 1Hz / s to 65536Hz / s, resolution is 1Hz,and positioning accuracy for blade can be up to 1mm.Resolving the questions of missing detectable rates made by manual during inspection in the paper, and increasing efficiency for inspection and the reliability of the experimental result. Experiment results show that this equipment can meet the challenge of the high-accuracy regulating speed for blade’s inspection.

In the design process of surface acoustic wave (SAW) device based on multistrip coupler (MSC), the characteristics of interdigital transducer (IDT) and device can not been directly achieved, and the layout structure of device can not be observed and checked. To solve some problems, the design platform of SAW device based MSC was realized in the Matlab design environment using the modular design. The design platform of SAW device based MSC consists of layout simulation module, characteristics simulation module and data output module. By means of realizing a SAW device based MSC with center frequency at 51.293MHz, the comparison and analysis between the design results and the actual test results are presented. Experiments results confirm that the platform can correctly design the device layout. The device characteristics achieved by the design platform are in good agreement with the actual measurement results by the network analyzer.

Zinc (Zn) is an important essential microelement for wheat. In order to study the characteristics of Zn absorption, accumulation and distribution in highly-yielding winter wheat (with a grain yield of 9 000 kg ha−1), field experiments were conducted in Gaocheng County of Hebei Province, China. Four winter wheat cultivars, i.e., Shimai 14, Jifeng 703, Shimai 12, and Shixin 828, and four cultivars, i.e., Temai 1, Shimai 12, Shixin 531, and Shixin 828, were used in the experiment, during 2004–2005 and 2005–2006, respectively. Plant samples were taken from the plots at each growing stage for Zn concentration analysis. The main results showed that the concentration of Zn in various above-ground organs of wheat was 9.5–112.5 mg kg−1 at different growing stages. The organ with the highest Zn concentration differed with the change of growth center at different growing stages. Accumulation of Zn in leaf blades was the highest among all the organs during early growing period, and more than 50% of the Zn accumulation was distributed to leaf blades before jointing, and higher than that to other organs. In late growing period, however, the accumulation of Zn in grains was the highest, and 58.1% of the Zn accumulation was distributed in grains at maturity. The total accumulation of Zn in wheat plant during its life span ranged from 384.9 to 475.9 g ha−1. The amount of Zn required for the formation of 100 kg grain yield ranged from 4.3 to 5.2 g. All the organs were ordered in such a sequence that leaf blades>spikes >leaf sheaths >stems according to their net absorption and transportation of Zn as well as their contribution to Zn accumulation in grains. 58.2–60.3% of the Zn accumulated in grains was redistributed from other organs, mostly from leaf blades. Concentration and accumulation of Zn in all the organs of wheat was high during early and middle growing periods, while accumulation of Zn in grains during late growing period mainly depended on the redistribution from other organs. According to these characteristics of Zn absorption and accumulation, Zn should be applied as seed dressing or basal fertilizer, so as to accelerate the early growth and Zn absorption of wheat.

In order to suppress the inrush current at start-up stage for synchronous boost converters, a novel start-up circuit with synchronous power-switch current-limit is proposed. A current sensing circuit with high accuracy for the synchronous power-switch and a linear feedback loop of current-limit are designed. The current-limit function is only enabled at start-up stage. In addition, the body node of the synchronous power-switches is supplied by a back-to-back diode structure from the input voltage and the output voltage, respectively, which effectively avoids the conduction of parasitic body diode on synchronous power-switches. The proposed technique has been successfully applied to a synchronous boost converter with 0.18μm 5 V CMOS process successfully. The experimental results show that the proposed method can effectively suppress the inrush current through synchronous power switch, and the output voltage rises smoothly without overshot.

This paper introduces a novel robot for outer surface inspection of boiler tubes. The paper describes the hardware system, wireless communication strategy, communication procedure and system software of the robot. The WLAN technology is used in the robot. It solves the problem of shielding generated by iron boiler and 11Mbps bandwidth made it possible for video and control stream real-time transmit within the same channel. Though TCP/IP protocol is robust, serial server is a transparent channel but cannot detect error and retransmit the data. In order to improve the reliability of serial communication, a new communication protocol is proposed.