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Large-scale integration of renewable energy resources in the Alternating Current (AC) grids will have a serious impact on power system operation. The development of the Direct Current (DC) is presented as a solution to overcome some of the negative impacts on massive micro-generation deployment. Over 100 years later, from the time when AC was proving superior over DC, the existing AC electric power grids, equipment, and transmission method facing a big challenge from DC. In this paper, what has changed since Edison and Westinghouse public battle are firstly discussed? Then the high voltage DC (HVDC) transmission system is depicted the developmental history and the system׳s structure, and the HVDC applications based on voltage-source converters (VSCs) combined with the renewable generation are introduced, such as onshore, offshore wind, and City Power Supply. Then, those key technologies are represented. Finally, how to build future electricity grid network and VSCs-HVDC may improve the world is explored, and some recommendations are proposed.

The maximum power point tracking (MPPT) methods for the photovoltaic (PV) power system have been considered by the experts in the whole world. A review of different MPPT methods is discussed in this paper. Firstly, the main methods at uniform radiation that will be deliberated are Hill-Climbing (HC), Incremental Conductance (IncCond), Perturbation and Observation (P&O), Fuzzy-Logic (FL), and Neural Network (NN). However, these existing methods have several drawbacks such as slow tracking speed, low tracking efficiency, which fail to extract maximum power at complex partial shading. Then, the more recent MPPT methods at partial shading are discussed to find the best MPPT control strategy, such as the particle swarm optimization (PSO) algorithm, Cuckoo Search (CS) method, and Fibonacci line search scheme, etc. The advantages and shortcomings of abovementioned MPPT methods are compared to find the optimal MPPT during partial shading conditions. It is imagined that this article will be a source of valuable information for PV professionals to keep abreast with the latest progress in the PV power area, as well as for new researchers to get started on MPPT.

The pathogenesis of intractable epilepsy is not fully clear. In recent years, both animal and clinical trials have shown that the expression of ATP-binding cassette (ABC) transporters is increased in patients with intractable epilepsy; additionally, epileptic seizures can lead to an increase in the number of sites that express ABC transporters. These findings suggest that ABC transporters play an important role in the drug resistance mechanism of epilepsy. ABC transporters can perform the funcions of a drug efflux pump, which can reduce the effective drug concentration at epilepsy lesions by reducing the permeability of the blood brain barrier to antiepileptic drugs, thus causing resistance to antiepileptic drugs. Given the important role of ABC transporters in refractory epilepsy drug resistance, antiepileptic drugs that are not substrates of ABC transporters were used to obtain ABC transporter inhibitors with strong specificity, high safety, and few side effects, making them suitable for long-term use; therefore, these drugs can be used for future clinical treatment of intractable epilepsy.

IPMC (Ion-exchange polymer metal composite) is a kind of novel artificial intelligent materials. It has a lot of good properties, such as light weight, good flexibility, easily cut in any size and shape, and can be used as both an actuator and sensor. A micro-force sensor based on the theory model of cantilever beam structure of IPMC is built up, which is applied to measure probe force during the micro operations under the environment of the cell injection.

Most of traditional manipulator does not meet experimental requirements of micromanipulation for its large structure and complicated driven mode. Comparatively speaking, using actuating and sensing performance of IPMC gripper can well be applied to specific micro operations and mechanical testing environment. This paper designs one kind of IPMC gripper of actuating and sensing performance based on micro operation and micro assembly, which is applied to grab the cells and fix under a microscope.

The recently-built school buildings have adopted novel heat recovery ventilator and air conditioning system. Heat recovery efficiency of the heat recovery facility and energy conservation ratio of the air conditioning unit were analytically modeled, taking the ventilation networks into account. Following that, school classroom displacement ventilation and its thermal stratification and indoor air quality indicated by the CO2 concentration have been numerically modeled concerning the effects of delivering ventilation flow rate and supplying air temperature. Numerical results indicate that the promotion of mechanical ventilation rate can simultaneously boost the dilution of indoor air pollutants and the non-uniformity of indoor thermal and pollutant distributions. Subsequent energy performance analysis demonstrates that classroom energy demands for ventilation and cooling could be reduced with the promotion of heat recovery efficiency of the ventilation facility, and the energy conservation ratio of the air conditioning unit decreases with the increasing temperatures of supplying air. Fitting correlations of heat recovery ventilation and cooling energy conservation have been presented.

Object detection involves solving two main problems: identifying the object and its location. This transforms the problem into a classification and localization problem. Currently, research shows that a convolutional neural network (CNN) can be used to solve the classification problem, and the object detection module incorporating a region proposal method can be used to locate the object. Although a CNN based on region proposals can achieve high recall, which improves detection accuracy, its performance cannot meet the actual requirements for small-size object detection and precise localization. This is mainly due to the feature maps extracted from the CNN and the quality of the region proposals. We present a cross-layer fusion feature network (CLFF-Net) for both high-quality region proposal generation and accurate object detection. The CLFF-Net is based on the cross-layer fusion feature that extracts hierarchical feature maps and then aggregates them into a unified space. The fused feature map appropriately combines deep layer semantic information, middle layer supplemental information, and shallow layer location information for an image to build the CLFF-Net, which is shared for both generating region proposals and detecting objects via end-to-end training. Extensive experiments using a casting dataset demonstrate its promising performance compared to state-of-the-art approaches.

To optimize the trajectories of the sun tracking system, the dual-axis sun tracking control method for a photovoltaic power system is discussed in this paper. The optimization goal is maximization of an electric energy production in the photovoltaic system considering the tracking system’s consumption. Firstly, the elevation angle and azimuth angle trajectories are described as a nonlinear and bounded optimization problem. Then the predictable trajectories of elevation angle and azimuth angle are derived by using the known formulas and knowledge. However, many factors affect the tracking trajectories, such as machine accuracy, formula error, the partial shading due to the shadow of clouds, trees, birds, dirt, and buildings, etc. Firstly, a novel system structure is introduced to improve the electrical energy consumption. Then, the perturbation and observation (P & O) control method is proposed to improve the tracking trajectories by decreasing the errors of machine and formula by combining with the conventional predicted method. The tracking efficiency of the dual-axis sun tracking system using the predicted method is compared with that using the predicted method combined with the P & O method. The simulation results presented in the paper show that the proposed method has excellent tracking characteristics compared with the fixed title, single-axis tracking, and dual-axis tracking using the single predicted method.

In order to realize the sustainable development of country and society, many countries have established their renewable energy law and development strategy no matter developed countries or developing countries. It is well known that China is the largest developing country in the world, and the per capita GDP ranks more than 100, however, the total GDP ranks the second due to the huge population amount, and just behind USA. Certainly, the total energy consumption amount is huge, and the big energy demand has brought a serious of environmental problems such as acid rain, water and soil pollution, and resource exhaustion, etc. Fortunately, China central government has regarded the serious question to realize the sustainable development in future. The renewable energy law has been established in 2005. Firstly, China's energy situation and existing environmental questions in past years is introduced in this paper. Secondly, the distribution and the application practice of different renewable energy were introduced. Then, China's renewable energy policy is detailed introduced in the following section. The next section discusses the existing questions. Based on these discussions, the development barriers and recommendations are introduced, respectively.

In order to gain the same amplitude、frequency and phase between the output voltage of the inverter and the grid voltage, the phase-locked loop (PLL) technology is widely used in grid-connected photovoltaic (PV) generating system, which is normally used to obtain instantaneous phase information to achieve the grid-connected purpose of PV inverter. The detective accuracy of frequency and phase of the grid voltage is directly affected by the PLL. Two software PLL technologies are compared by using the simulation analysis which is based on the d-q transformation. To provide the basis for the design of grid-connected inverter, the advantages and disadvantages of two software PLL technologies are analyzed under different grid failure conditions, such as one phase voltage dropped, two of three phase voltage (TPV) dropped, grid frequency mutated, and grid voltage offset, etc. Particularly, the appropriate PLL technology can effectively improve the grid-connected ability of PV inverter under the grid voltage offset or unbalance conditions.

For getting an objective assessment of product quality efficiently, the comprehensive evaluation method of generalized product quality was used to evaluate products. At the same time, the index weights were determined by entropy weight method. Taking air screener as example in this paper, we used the comprehensive evaluation method of generalized product quality which was based on entropy weight method to evaluate many types of air screeners and used the software which was made with VB to calculate the data, it made the evaluation process more objective and reliable. The result which was got with this method provided the scientific basis for users to choose the products and for companies to improve the product's quality.

According to extensive literature research, we introduce and summarize both physical, chemical properties, main hazards of phenol and the recent phenol water pollutions. We get the problem that it’s hardly to meet the standard and ensure the safety of water supply because of the low removal ratio in the process of water treatment when the water source is polluted by sporadic phenol pollution. After we analyze and compare the removal technology in polluted water and potable water respectively, we know the removal ratio of polymeric aluminum chloride-powdered activated carbon and permanganate potassium- activated carbon is significantly higher than activated carbon only, but the output water couldn’t reach the standard when facing high concentration phenol pollution (500μg/L). The biological technologies and membrane methods used in waste water treatment are introducing into the potable water treatment.

This paper introduces the basic principle of the microscopic visual servoing system based on image and summarizes systematically about the researching situation of microscopic visual servo based on image at home and abroad. From three aspects, which are Jacobin matrix calculating, automatic focusing technology of microscopic lens, and microscopic image fusing technology, it proposes some key problems to be urgently solved about the microscopic visual servoing based on image.

The rub-impact fault of Jeffcott rotor system which is generally made of an elastic shaft with supported by two bearings at ends and a lumped mass at the mid-span of shaft is the main research subject of this paper. The mechanical model and finite element model of a lump mass at the mid-span of shaft is set up. The dynamics of it are studied by nonlinear finite element method under the rub-impact conditions, and by investigating the effects of stiffness of stator and the clearance between rotor-stator. From the study results, use finite element method to study the rotor system failure problem is intuitive and convenient, high accuracy, high reliability, can be widely applied.

Today, the large-scale Photovoltaic (PV) power system, connected to grid, is in their advanced development stage and is extremely interest in whole world. The real large-scale PV array can be partially shaded by the shadow of building, cloud, bird and dirt. The output characteristic of PV materials in partially shaded conditions is strong nonlinear, and there are multi local peaks in output power voltage curve, and the only one real peak exists in these local peaks. Certainly, the maximum power point tracking (MPPT) method is very important to extract the as much as possible energy from the costly PV materials. The variant weight Particle Swarm Optimization (PSO) method is proposed to track the real peak by using the excellent multi-peak value optimization characteristic of PSO algorithm. The simulation results shows that the proposed PSO method can improve the response speed and output efficiency of PV materials in partial shading as compared to the conventional Incremental conductance (IC) method.

An efficient Maximum Power Point Tracking (MPPT) control method is important to increase the output efficiency of a photovoltaic (PV) material. The output power of PV power system depends on local irradiance conditions. The output characteristics of large-scale PV materials under partial shading conditions have multiple maximum power points, which make the tracking of the actual maximum power point (MPP) a difficult task. A novel combined fuzzy and perturb and observe (PO) control method is suggested to extract maximum power from the PV materials under these conditions. The ability of the proposed method and its increased performance as compare with the traditional fuzzy control method is evaluated by means of experimental tests performed on a real PV power system and based on the MSP430x44x microcontroller.

The price of photovoltaic (PV) materials and wind generating system (WGS) materials is costly, and the stand-alone PV or WGS can not steadily supplied electric power for end user, fortunately, solar power and wind power can compensate well for one another under various locations and climatic conditions, an efficient maximum power point tracking (MPPT) method for hybrid solar-wind electricity materials is important to extract maximum power from wind and solar energy because of the costly price of PV and WGS. The fuzzy MPPT method is used to track the maximum power point (MPP) of distributed small WGS and PV and hybrid solar-wind system. In order to decrease the output oscillation, the immune response feedback principle (IRFP) is used to improve the track speed and response speed and robust of output characteristic of electricity materials, the results displayed that the immune theory can effectively improve the performance and the stability of electric power of stand-alone or hybrid generating materials.

Along the eastcoasts of China are large bodies of water, China has abundant ocean energy resource, such as the theory reserves of tidal resource is about 0.2 billion kW, as early as 1958, Jizhou tidal power station is the first tidal power station in China, which built in Shunde, Guangdong province, and more than 40 small tidal power stations are built in east coastal region in 1960s, and the total installed capacity is about 0.5 MW. But it is a pity, the application and development of tidal energy has not been regarded by the government and ordinary people due to the investment of power plant is big and the technology is not mature, so there are only several small tidal power stations in China, and Jiangxia tidal power station with an installed capacity of 3.2 MW is the most famous. Fortunately, with the rapid development of Chinese economic and society, the renewable and sustainable energy have been regarded by Chinese government, and the application and development of wind energy and solar energy is increasing in an incredible speed, and more and more specialists began to regard the application of tidal energy, and they thought that tidal energy can relieve the energy stress of east coastal region, and many layout of tidal energy exploitation is unfold in recently. This paper discusses the distribution zone and current developmental situation of tidal energy in China. Then, some application practice is described, such as tidal power station and tidal stream turbine. The policies and law of China central government and local governments are described in the following paragraph. At the end, the developmental prospect of tidal energy in future China and the development barriers and recommendations are introduced, respectively.

The steady and maintainable electric power provides the development momentum of a country's industrialization, which is indispensable to every country at present. It is well known that China is the largest developing country in the world. With the rapid development of economy and society, energy demand of Chinese society is increasing in an incredible speed, i.e., the annual accumulative total capacity of electric energy is about 0.1 billion kW, and the most of them is provided by the fossil fuel resource, and the share is about 90% in China. Certainly, it is a very inappropriate energy structure, so the sustainable development of country is impossible in future, the status must be improved in order to achieve sustainable development. Fortunately, China has large country area, and there are abundant solar resources. Development and application of solar energy have been regarded by the government and ordinary people, and they thought that solar energy can provide more and more electric energy in future, and more and more actual examples have been applied in the last decades, which are supported by central government and local governments. This paper discusses the distribution zone and current developmental situation of solar energy in China. Then, some application practice is described, such as solar energy greenhouse, solar energy hearth, solar water heater, solar lighting system, solar water pump, distributed generation (DG), grid-connect photovoltaic generation (GPG) and wind–solar hybrid system. The policies and law of China central government and local governments are described in the following paragraph. At the end, the developmental prospect of photovoltaic (PV) in future China and the development barriers and recommendations are introduced.

China is the largest developing country in the world. At present, more and more energy demand gives immense pressure to Chinese government. The inappropriate energy structure must be improved by Chinese government in order to achieve the sustainable development of economy and society. Development and application of renewable energy, such as wind energy, solar energy, biomass energy, etc., have been regarded by the government and the local people in the past 10 years, and more and more actual examples have been established, which are supported by government and plants in China. It is well known that there are abundant wind and solar resources in China. This paper presents the distribution zone and development and application practice status in China. However, a common drawback is existing in the stand-alone wind energy and solar energy generating power system, which is the unpredictable output electric power, and the output power depends on the unpredictable weather and climatic changes. Fortunately, the wind–solar hybrid generation system can partially overcome the problems. The conventional structure and key technology of stand-alone wind–solar hybrid generating system, the current status and outlook of wind–solar hybrid energy system are presented in the paper, for example, the city road lighting system, distributed generation, photovoltaic (PV) water pumping for irrigation, etc. At the end, the policies and laws of China central government and local governments are described, and the development barriers and recommendations are introduced.

After successful pilot projects, Zhejiang Province, China, decided to systematically scale-up health promoting schools (HPS) over the entire province of 47 million. This study describes the interventions and self-reported changes in attitudes, knowledge and behavior during the first phase of scaling-up. Group interviews were conducted with a sample of 191 participants (school administrators, teachers, students and parents) from nine schools with a total of approximately 15 200 students. Grounded theory guided data analysis. Schools implemented all HPS components (school health policy, physical school environment, psychosocial school environment, health education, health services, nutrition services, counseling/mental health, physical exercise, health promotion for staff and outreach to families and communities), adapted to local circumstances. Participants reported a range of changes in attitudes (paying more attention to health, attaining better 'psychological quality' and confidence, forming friendships between teachers and students and feeling more relaxed), knowledge and concepts (increasing knowledge about various health issues, developing a broader concept of health and gaining better understanding about the HPS concept) and behavior (actively participating, increasing physical activity, improving sanitary habits, reducing or quitting smoking, eating more nutritiously, increasing safety behavior, sustaining less injuries and improving parent-child communication). This qualitative study shows the feasibility and efficacy of implementing HPS in Zhejiang Province, China.

Puerarin, the main isoflavone glycoside extracted from Radix Puerariae, is an isoflavone traditional Chinese herb. Previous studies have demonstrated that puerarin could regulate osteoblast proliferation and differentiation to promote bone formation. However, the effect of puerarin on the process of human osteoblasts (hOBs) apoptosis is still unclear. In this study, we detected the function of puerarin on serum-free-induced cell apoptosis using ELISA and TUNEL arrays and then found that the mortality of hOBs was significantly decreased after exposure to 10−10–10−6 M puerarin and reached the maximal antiapoptotic effect at the concentration of 10−8 M. In addition, compared with the control group, puerarin notably increased the Bcl-2 protein levels while it decreased the Bax protein levels in the hOBs in a dose-dependent way. 10−7 M puerarin decreased the Bax/Bcl-2 ratio with a maximal decrease to 0.08. Moreover, puerarin activated ERK signaling pathways in hOBs, and the antiapoptotic effect induced by puerarin was abolished by incubation of ERK inhibitor PD98059. Similarly, the estrogen receptor antagonist ICI182780 also suppressed the inhibitory effect of puerarin on hOBs apoptosis. In conclusion, puerarin could prevent hOBs apoptosis via ERK signaling pathway, which might be effective in providing protection against bone loss and bone remolding associated with osteoporosis.

An efficient Maximum Power Point Tracking (MPPT) method is important to increase the output efficiency of a photovoltaic (PV) generate system. It is well-known that the different photovoltaics have different n and Io. The conventional MPPT algorithm is impossible to quickly acquire the maximum power point (MPP), and the essential reason is not known the actual values of the n and Io. Theoretical and simulative results show that a piece of photovoltaic has same photocurrent, and the optimal output current and voltage are different under different n and Io conditions. Perturb and observe (PO) method is used to acquire the actual n and I. Then an easy maximum power point tracking algorithm is described which based on the actual n and Io. Furthermore, it is simple and can be easily implemented in digital signal processor (DSP). The maximum power point tracking course became a calculation course by using DSP base on the known coefficient. The simulation results verified the correctness and validity of MPPT method.

According to the difficulty of urban bus stop planning, a method which is based on optimization theory is introduced. First, the minimum passengers’ total traveling time model base on the shortest stop distance is adopted to calculate the optimum stop distance and determine the number of bus stops. Then, the bus stop coverage rate model is used to predict the development scale of urban bus stop. Finally, based on a comprehensive analysis of these two models, the rational development scale of urban bus stop is determined. The method has been applied in Zhanjiang’s public traffic planning, the experiment shows that the method is brief and easy, it has some real work significance to public traffic planning.

Writing and browsing education blogs has become one of the important methods of e-learning. Learners can search the interesting resources from these education blogs. However, the traditional blog search only provides keyword-based matching, lacking automatic extraction of learner interests and further interest-related blog recommendation. It describes the design and implementation of an interest mining and learning resources recommendation system. The system adopts interest mining technology and can automatically identify the learner?s interests and recommend interest-related blog initiatively. Experimental result shows that the system is effective.