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In this study, we synthesized carboxymethyl chitosan-graft-poly(ε-caprolactone) (CMCS-g-PCL) by grafting ε-CL onto the hydroxyl groups of CMCS via ring-opening polymerization. The graft copolymers were characterized by 1H NMR spectroscopy and thermogravimetric analysis (TGA). Then use the graft copolymer to produce the micelle by solvent-evaporation method. The DLS and TEM were utilized to evaluate the particle size and morphology and showed that the micelles were in a well-defined spherical shape with a uniform size distribution. The results indicated that the size of range is below 200 nm and could be used as drug carrier and have better active cellular uptake.

The transformer rated secondary load in electric energy metering device was much larger before electric energy metering device revamp. Big energy differences exist before and after the revamp. The reason of making down rated secondary load and its influence on transformer error and energy metering are analyzed in the presented work.

Many error abnormities and verification difficulties appear in high voltage transformer field error tests. Field verification is with site and duration limit, so it is important to timely solve problems and complete tests. Field practical problems and solutions are expounded through technical analysis for technicians in the presented work.

The Martian dust is a serious threat to the spacecraft and rover. It would hinder the functioning of equipment and limit mission duration. The paper introduces a system, which uses supersonic gas jet formed by a Laval nozzle to blow off the accumulated dust. The related parameters have been investigated and the flow fluid field has been simulated.

The stress of the two kinds of hanging centrifuge drum with different perforation shape are simulated by using ANSYS, and the perforation shape is optimized. The results show that the stress concentration of ellipse perforation is lower than that of the circular one under the same condition, and the maximum stress of ellipse perforation is minimum when the ration of major and minor axis of ellipse perforation is a/b=2.0.

A lateral-torsional coupled vibration model of the slewing mechanism of a hydraulic excavator is developed with consideration of the effect of lateral vibration and torsional vibration of sun gear and planetary gear on mesh displacement, the mesh stiffness of gear pairs, the bearing stiffness of the planetary and the coupling relationship of two stage planetary gear trains. The dynamic response of the slewing mechanism of a hydraulic excavator is obtained. Compared to the pure torsional vibration, the lateral-torsional vibration model is more reasonable.

In recent years, in order to achieve a stable and efficient output, the research about the method of efficient controlling has become a significant and popular research topic in the academic field. In this paper, a novel electromagnetic transient model of photovoltaic cells is proposed and established with the method of Maximum Power Point Tracking (MPPT) and forward-feed controll. Dynamic simulation proves that the model can reflect working situation of the photovoltaic systems correctly under different environment parameters.

Demand response (DR) has become an important part of smart grid, mainly for modulating load curve, emergency treatment, balancing the demand and supply of power system. The features of smart grid-self healing and interactive-give the new meaning to DR. In smart grid, the promotion strategies of ISO/RTO in energy and auxiliary service markets implement DR programs in the project of auxiliary services and can reduce energy consumption. This paper summarizes the global related researches and practices, including the classification, progress of each subclass, the future development potential and DR program outlook in China, and puts forward the following two ideas: 1) The DR for single market cannot satisfy the needs of smart grid, advanced measurement and remote sensing technologies shall be made to implement the DR programs combining with multiple markets; 2) The service agency of DR on transmission and distribution shall be conducted and supervised by the government departments.

This paper raises a model which concerns about spinning reserve capacity of output and predicted error based on chance-constrained programming. The distribution function is established on the load demand of electric vehicles. Considering the complementarities of electric vehicles and small hydro and wind power generations, this paper constructs a dispatch model on the participation of electric vehicles in reserve capacity and peak regulation. Joint operation of different units in the system achieved by genetic algorithm examines the influence from joint dispatch of electric vehicles and small hydro and wind power generations on spinning reserve capacity and peak regulation plan, setting different values of confidence to make comparison of electric charge in the entire system. According to the real operation statistics of an electric company in a certain province, the reliability and accuracy of the model was guaranteed.

This paper introduces the smart substation hardware-in-loop simulation training system structure based on the analysis of the smart substation simulation training requirements. The training system scheme has been designed according to the different training requirements to support training of staffs in smart substation for operating and maintenance in all possible ways. Combining with the practical solutions, the application of the training system will be introduced. This design scheme will take important effect in the development of smart substation and its operating and maintenance training.

Numerical method is extensively used to determine the workspace of a robotic manipulator. However, four or more degree manipulator mathematic models are too computationally intensive to be finished by computer. In this paper , a fast algorithm for workspace of a robotic manipulator is introduced. The method is based upon the singularity analysis of serial manipulator so that the computation amount is greatly reduced. The practical example of 6R manipulator is treated with this method. Its workspace is drawn and determined.

With the widely use of the non-linear elements, the unreasonable parameters setting or interruption to HVDC system, converting stations may produce a kind of non-characteristic harmonics. In order to study its impact to the system, traits of these harmonics are analyzed based on the power system simulation tool—EMTDC. Contents and amplitudes of the harmonics in the DC line are detected by the expansion Prony algorithm, after that a basic analysis is given. Analysis of non-characteristic harmonics on the DC line is helpful to study the harmonic losses, the influence to electrical equipments and power qualities, especially to the design of the DC filters in HVDC system.

The grounding capacitive current is one of the most important parameters of ungrounded neutral system. Usually this parameter is obtained with the method of additional capacitor or metal grounding. However, the former is complicated and the additional capacitor has negative effects on measurement results, and the later is dangerous when used in testing. In view of that, the paper proposes a new method to calculate grounding capacitance current based on the data of single-phase-grounding faults in power system with indirectly earthed neutral. This method reduces the error by using the least-square method .The ATP simulation results show that this method is accurate basically.

Urban culture is the foundation of the development of city，and discussions on its inheritance have been held for a long time. It is necessary to protect the space-time characteristics of historical heritages and absorb the contemporary elements. Only in this way, can we ensure the cultural life of historic blocks, and offer it new meanings.

he paper introduces the analysis of finite element for gearbox’s intensity, then optimal design for gearbox has achieved good optimal result leading to the weight reduced 3746kg, 23.18%less than original weight with the thickness of the main board as deign variables and the stress and displacement as constraint conditions. The optimization results have practical significance on the structural optimization and the weight of the gearbox, offering reference data for weight reduction of gear box design.

In order to investigate the effects of grease lubrication on fretting wear of ball bearings, a series of fretting wear tests were performed under the dry condition and grease lubrication by a self-made fretting wear rig. And tests were completed at different angles, load and number of cycles. The results showed that the grease lubrication can effectively reduce fretting wear; reduction effects increase as the oscillation amplitude increases and load decreases; oxidation in fretting wear decreases as number of cycles increases under grease lubrication; and wear mechanism is diffrent at under different lubrication conditions.

Little research has considered brand experience and relational benefit together in a single model. This study was designed to investigate how brand experience enhances relational benefit. Using a self-administered questionnaire survey, 182 effective respondents from college students were used for the study. In this paper, an integrated model was established through the inclusion of brand familiarity, brand image, brand personality. The study finds that brand experience could be positively associated with relational benefit indirectly and that brand familiarity, brand image and brand personality could serve as mediators between them. The finding suggests that practitioners better understand customers’ perceptions towards relational benefit and help them in developing marketing strategies to gain relationship with consumers.

A new bamboo weaving machine, in which automatic control system is employed, is introduced in this paper. The system deals with the images firstly, and then controls bamboo weaving by means of electromotor and transmission devices. Different algorithms, such as lift wavelet, bivariate rational interpolation and Ostu are used in image processing. The minimum width of the bamboo filament is 0.7mm. The maximum number of the bamboo filament in the warp and weft direction is 360 and 430 respectively. Various beautiful bamboo artware can be weaved automatically by this machine in a short time.

In 5-axis NC machining, if the worktable rotary center or the cutting tool swivel center offset, in program blocks, the cutting tool position will also change and the compensation is needed. The author studies the mathematic relationship among the rotary center offset values, rotary angle A, B and C and the cutting tool position compensation values and designs the computer automatic processing algorithm which can rapidly and accurately calculate the compensation values for position change of the cutting tool and amend the cutting tool position in program blocks so as to obtain a practical NC program.

In order to accurately estimate tool life for milling operation, a novel tool condition monitoring system was proposed to improve classifying precision in different cutting condition. Lots of features were extracted from cutting forces signal, vibration signal and acoustic emission signal by different signal processing method, only a few features selected by principal component analysis (PCA) according to contribution rate, and constructed as input vector. The relation between tool condition and features was built by radial basis probability neural network which control parameter of kernel function and hidden central vector were optimized by improved genetic algorithm. The experimental results show that the method proposed in the paper achieves higher recognition rate, good generalization ability and better available practicality.

In order to explore the cutting rules of the 43-inch vane material --1Cr12Ni3Mo2VNbN on the turbine vane, and research the stress in cutting area, the strain as well as the temperature distribution and the variation, providing the reference data for the large-scale vane-root milling cutter's geometric parameter design and the cutting parameter optimization, the authors employed ANSYS / LS-DYNA finite element method to simulate and research the cutting process of the vane material. The authors adopted the two-dimensional plane element 2D SOLID l62 of the single-point integration Lagrange algorithm to establish the finite element cutting model, and established the Cowper-Symonds constitutive models based on the vane material, applied the 2D-r adaptive meshing to simulate the separation of the chip and workpiece. Obtain the distribution and rules of the stress, the strain as well as the temperature in the cutting area, and greatly shorten the period of the vane root milling cutter’s designing and trial-production.

In order to estimate and predict the screw performance in the process of machining, a screw life monitoring system was built. Current signal was processed and features sensitive to cutting force were selected, a virtual force sensor was constructed to model the relation between cutting force and current by BPNN. Cutting force was indirectly calculated by the model, so the rating life of screw in different condition could be known and residual life also be reckoned by historical database. A three-way vibration sensor was installed on screw pair base; screw condition could be induced by HMM which input was 15 vibration signal features. As machining condition changed, corresponding new HMM would be built by adaptive method. Finally, the residual life of screw could be gotten by multi-HMM and BPNN. The experimental results show the model proposed in the paper is effective and high precision.