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Copyright of Journal of South China University of Technology (Natural Science Edition) is the property of South China University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Transactions of the Chinese Society of Agricultural Engineering is the property of Chinese Society of Agricultural Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the contradictory relationship between power generation and ecological benefits of Qiao-qi Hydropower Station, this paper establishes a reservoir multi-objective optimization operation model with the goal of maximizing the annual power generation and average ecological flow of Qiao-qi Hydropower Station according to the ecological flow discharge methods of different time scales. The model is based on the platEMOopen source toolbox of MATLAB, and runs the ecological water release model generated by the Tennant method based on the annual and monthly flow processes, and analyzes the benefits of power generation in the two modes. The results indicate that when the ecological flow is 20%~30% of the average flow for many years, the Pareto surface of the two goals of ecological flow and annual power generation shows an approximately linear trend; the optimal power generation is obtained under the same leakage as the actual ecological flow. The amount of electricity is 836 million kWh, which increases by 21 million kWh compared to the actual power generation of the year; the ecological water release model based on the annual scale has more power generation benefits than the ecological water release model based on the monthly flow process. [ABSTRACT FROM AUTHOR]

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the study of renewable energy power generation for microgrid becoming more and more significant, the microgrid's safe and economic operation has been paid more and more attention to. The microgrid economic operation cannot go well without perfect energy optimization scheduling, and making full use of energy storage units, coordinate microgrid internal power supply, storage and load, and the power/energy flow between the microgrid and the large power grid. Maximizing the microgrid operation efficiency under the premise of keeping balance between the supply and demand has become an urgent problem needing solution. Aiming at the problems in current literature, the dynamic optimization and static optimization models can't combine the day-ahead scheduling with real-time scheduling and fail to make full use of the storage and removal effect of energy storage units. In this paper, firstly, a multiple-time scale optimization scheduling scheme is put forward using the state of charge of energy storage unit as the bond between day-ahead scheduling and real-time scheduling. In day-ahead scheduling stage, a scheduling cycle is divided into 24 hours. In state of charge planning, the controllable micro power on-off plan and power generation plan are made based on the short power generation/consumption prediction data. In real-time scheduling stage, following the controllable micro power on-off planning and the state of charge of day-ahead scheduling, the future 5-15 minutes state of charge, charge and discharge power and the micro power supply power output planning is developed based on the real-time super short power generation/consumption prediction data. The day-ahead optimization model for the microgrid is also put forward, using the state of charge of energy storage units, controlled micro power supply power, and on-off state as control variables. The model puts four parts as constraint conditions within 24 hours, the controllable micro powers output, state of charge of energy storage unit, the interaction power between microgrid and power grid, and the power balance of microgrid. It takes the maximum utilization rate of renewable power generation, with minimum power supply cost of day as the goal. Then it takes the maximum utilization of renewable power, with minimum power supply cost of a day as the goal. It achieves the goal of maximum utilization of renewable energy power through meeting the demand of equivalent load, which simplifies the elements of the goal. To solve the multiple constraints, nonlinear, and mixed integer dynamic optimization models, it uses a genetic algorithm based on matrix real-coded which has strong global optimization ability, suited for parallel processing. Finally, an example of microgrid is given using the optimization model and algorithm which are proposed in this paper. The optimization scheduling results of parallel bidirectional power flow model and parallel unidirectional power flow model show that by reasonable control of state of charge in each period, the given optimization scheme can maximize utilization of renewable energy power and minimize power supply cost of microgrid whi.e at the same time achieving peak sharpening effect for the grid. [ABSTRACT FROM AUTHOR]

Halon-1301 (CF3Br) can make Br radicals with UV radiation, which poses a great threat to the ozone layer in the atmosphere. Necessary methods should be taken for the degradation of the exhausts of Halon-1301. In this paper, density functional (DFT) theory at B3LYP/6-311G++(d,p) level are employed for the study of dissociation properties and spectra of Halon-1301 in external electric field, including bond length, total energy, HOMO-LUMO energy gap, infrared spectra and dissociation potential energy surface (PES). The obtained results show that, with gradually increasing the external field from 0 to 0.03 a.u. along the molecular axis Z (C—Br bond direction), the total energy decreases, while the dipole moment decreases at the beginning and then increases. With the climbing of the field, HOMO-LUMO energy gap increases, and C—Br bond length increases while C—F bond length decreases. The variations of vibrational frequency and intensity of molecular IR spectra in external electric field are also investigated. Further studies show that with increasing the external electric field from 0 to 0.03 a.u., the dissociation PES along C—Br bond becomes unbound with disappearing of the barrier for the dissociation. The external electric field of 0.03 a.u. is sufficient to induce the degradation of CF3Br with C—Br bond breaking. Such results provide an important reference for the degradation of Halons via the external electric field.

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The paper considers a power system which consists of a power plant and two symmetrical electricity companies, and studies the optimal procurement strategies of electricity and renewable energy certificates (RECs) of the companies. The analysis shows that although a certain proportion of RECs is required when the trade is taken place, the demand of RECs is dependent on the demand of electricity and the optimal procurement decision of RECs is independent of the trade of electricity. It finds that, the ratio of the wholesale price of the RECs and the government fine will have impact on the electricity companies' procurement strategies of the RECs, if the ratio is small, the electricity companies tend to purchase a larger amount of renewable energy certificates, and vice versa. The paper also studies the optimal procurement strategy and cost of the two companies whose demands are related, and finds that when the demands are positively related, with the increase of the correlation coefficient, the company procurements less RECs, and its cost decreases; when the demands are negatively related the opposite conclusion obtained; and the government can reduce the impact by adjusting the fine. [ABSTRACT FROM AUTHOR]

This paper investigated the capacity of plants (Schlumbergera truncata, Aloe vera var. chinensis, Chlorophytum comosum, Schlumbergera bridgesii, Gymnocalycium mihanovichii var. friedrichii, Aspidistra elatior, Cymbidium kanran, Echinocactus grusonii, Agave americana var. marginata, Asparagus setaceus) to generate negative air ions (NAI) under pulsed electric field stimulation. The results showed that single plant generated low amounts of NAI in natural condition. The capacity of C. comosum and G. mihanovichii var. friedrichii generated most NAI among the above ten species, with a daily average of 43 ion · cm(-3). The least one was A. americana var. marginata with the value of 19 ion · cm(-3). When proper pulsed electric field stimulation was applied to soil, the NAI of ten plant species were greatly improved. The effect of pulsed electric field u3 (average voltage over the pulse period was 2.0 x 10(4) V, pulse frequency was 1 Hz, and pulse duration was 50 ms) was the greatest. The mean NAI concentration of C. kanran was the highest 1454967 ion · cm(-3), which was 48498.9 times as much as that in natural condition. The lowest one was S. truncata with the value of 34567 ion · cm(-3), which was 843.1 times as much as that in natural condition. The capacity of the same plants to generate negative air ion varied extremely under different intensity pulsed electric fields.

Copyright of Journal of Harbin University of Science & Technology is the property of Journal of Harbin University of Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Transportation is the key industry of urban energy consumption and carbon emissions. The transformation of conventional gasoline vehicles to new energy vehicles is an important initiative to realize the goal of developing low-carbon city through energy saving and emissions reduction, while electric vehicles (EV) will play an important role in this transition due to their advantage in energy saving and lower carbon emissions. After reviewing the existing researches on energy saving and emissions reduction of electric vehicles, this paper analyzed the factors affecting carbon emissions reduction. Combining with electric vehicles promotion program in Beijing, the paper analyzed carbon emissions and reduction potential of electric vehicles in six scenarios using the optimized energy consumption related carbon emissions model from the perspective of fuel life cycle. The scenarios included power energy structure, fuel type (energy consumption per 100 km), car type (CO2 emission factor of fuel), urban traffic conditions (speed), coal-power technologies and battery type (weight, energy efficiency). The results showed that the optimized model was able to estimate carbon emissions caused by fuel consumption more reasonably; electric vehicles had an obvious restrictive carbon reduction potential with the fluctuation of 57%-81.2% in the analysis of six influencing factors, while power energy structure and coal-power technologies play decisive roles in life-cycle carbon emissions of electric vehicles with the reduction potential of 78.1% and 81.2%, respectively. Finally, some optimized measures were proposed to reduce transport energy consumption and carbon emissions during electric vehicles promotion including improving energy structure and coal technology, popularizing energy saving technologies and electric vehicles, accelerating the battery R&D and so on. The research provides scientific basis and methods for the policy development for the transition of new energy vehicles in low-carbon transport.

This paper describes 5 national standards related to the term on the residual voltage with different indicators. Compare the advantages and disadvantages of various test methods. Finally, give suggestions on improving the testing method.

The short-arm air-cathode microbial fuel cell (ACMFC) was constructed using a cramp to fix the proton exchange membrane (PEM) and carbon paper with 0.5 mg/cm2 onto the short-arm side of the anode chamber. Exoelectrogens on the surface of graphite rod were enriched by a sludge microbial fuel cell from the anaerobic digestion sludge. And the cyclic voltammetry result showed these microbes had electrochemical activities. Using the graphite rod covered by exoelectrogens as the anode and sodium acetate as the substrate, the short-arm ACMFC showed a maximal power density (Pm) of 738 mW/m2, internal resistance (Ri) of 280 omega and open circuit voltage (OCV) of 741 mV. Continuous sparging the anode chamber with nitrogen or removal of the proton exchange membrane enhance the Pm of the cell to 745 mW/m2 and 759 mW/m2 respectively. When both of the two measures were used together, the Pm reached up to 922 mW/m2. Under these three conditions the Ri of the cell was kept around 280 omega. When the substrate concentration was 12.62-100.96 mg/L and external resistance was 510 omega, the maximal voltage of the cell and the substrate concentration showed an obvious linear relation (R2 = 0.99). But when the concentration was above 100.96 mg/L, the maximal voltage stably kept around 302mV(the external resistance was 510 omega). However, the Coulombic efficiency of the short-arm ACMFC gradually increased with the increase of the substrate concentration, from 31.83% to 45.03%.

The environmental test for medical electrical equipment may be interrupted by power cut or the equipment broken and so on. For the purpose of standard and valid testing, this paper puts forward a project about how to deal with the interrupted disposal of environmental test for medical electrical equipment. The project aims at the environmental requirements and test methods for GB/T 14710--93.

This paper introduces the temperature rising experimental process and some matters needing attention when the transformer is normally loading. And an analysis of the uncertainty for transformer's temperature rising is also made based on the practical examples' data.

This paper aims at the tense situation of energy demand and supply and analysis the current situation and problems of energy supply and demand in Guangzhou. We predict total demand of energy which will be 4534.7 x 10(4) of standard coal in 2010 by using the department analysis method and sequence method, and the balance between supply and demand of energy will be 45,000 thousand tons of standard coal. From the primary conclusions of our empirical analysis and together with the overall environment of energy in Guangdong and China, we think the development strategies of energy in Guangzhou in the future should involve several main points as following: (1) Energy of Guangzhou should base on the overall energy development programming of China and that is, it should depend on the "transmission of electricity from the western to the eastern region", power incorporation of Sanxia, power generated of water energy, nuclear power and new resource. (2) Stop setting up or expending the natural monopoly and resource oriented Huangpu thermal power plant located in the windward direction of summer of Guangzhou which has serious pollution and consumes large quantities of energy. (3) It should not absolutely depend on the coal of the poor mountainous region of Guangdong and small power station and can make full use of the resource potential.

Dissimilatory Metal Reduction Bacteria play an important role in the anaerobic environment. This kind of bacteria gains energy by coupling the oxidation of organic acid or sugars to the reduction of metal oxides. The graphite electrode rode can also be used as the final electron acceptor due to its similarity to solid metal oxides. Based on this biological mechanism, Dissimilatory Metal Reduction Bacteria Rhodoferaxferrireducens was used to construct a suit of microbial fuel cells with sugars as fuel, and the process and mechanism of electricity generation was studied. Rhodoferax ferrireducens was inoculated into the anode chamber in which a graphite electrode served as the final electron acceptor and glucose as the sole electron donor. It was showed that current density was up to 158mA/m2 with the resistance of 510omega at the normal temperature (platform voltage was around 0.46V, the effectual electrode surface was 57cm2). Following 20days' growth a large amount of bacteria cells attached to the electrode surface had been observed through the SEM images. The plandtonic cell protein concentration was 140mg/L and the attached biomass of electrode surface was 1180mg/m2 determined by the Bradford method, which indicated quite a few bacteria attached to the electrode. By analyzing the voltage value measured by the data acquisition system, it was proved that microbial electricity generation attributed mainly to the electrochemically and biologically active cells attached to the electrode, while the planktonic cells had no ability to catalyze electricity generation and almost had not electrochemically and biologically active. Furthermore, this kind of microbial fuel cells exhibited a good electrochemical cycle property and proved to be efficient in biomass utilization and energy restore since other sugars like fructose, sucrose, even xylose, could be oxidized and finally decomposed. Vast waste biomass in the form of carbohydrates is discarded in the environment. Not only is contamination of the environment caused by the discarded biomass, but also abundant energy stored in the biomass is drained away in vain. The sugar-based microbial fuel cells constructed by Rhodoferax ferrireducens could effectively transform the energy stored in sugars into electricity. Meanwhile, the microbial fuel cells presented in this paper, which could work cleanly at normal temperature with a good cycle property, showed a promising future application in this field.

This paper introduces the principle of invert transformer of high frequency X-ray machine, and analyzes its main constitution. Meanwhile, a scheme based on SG3525 for closed loop voltage regulation is given. The experimental result testifies its efficiency and utility.

In the past years, scaled energy spectroscopy is under active investigation because this method can simplify the analysis of atomic spectra in the external field based on classic mechanics. A fully computer-controlled experimental system to study the constant scaled-energy spectroscopy was established and described in this paper. The excitation energy E and the strength of the external electric field F were controlled synchronously to keep the scaled-energy epsilon = E/square root of F constant. With this system, constant scaled-energy spectra of Strontium Rydberg atoms at epsilon = -3.0 in a static electric field were successfully recorded for the first time, and the recurrence spectra were obtained by a Fourier transform.

Copyright of Chinese Journal of Liquid Crystal & Displays is the property of Chinese Journal of Liquid Crystal & Displays and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper has an overall review of the historical process of electrocardiographic development and the origination of modern electrocardiography in retrospect and also has an analysis of the scientific background, the important events and the historical effect of outstanding figures throughout the development. The experience and laws contained in the historical development are briefly summerized in this paper. At the same time the authors point out that the establishment of modern electrocardiography and the related technical development are crystallization of the wisdom and the result of the hard work of many scientists including the figures who should have been awarded Nobel Prizes.

It is an important safety checking item to check leakage current of medical electric equipments. In the national standard, there are definite and strict stipulations for the leakage current-checking and the checkers. But this important checking is often misrepresented with general current measurements. So the checking is not up to the standard and the results are not dependable. In this paper, the special demands for the checking and the key technique of the checkers have been expounded in detail.

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Home energy management system as a intelligent embodiment of smart grid in the users side, should be built on the basis of electricity safety. The main electrical accident of house is line overload. In the optimization of smart household appliances, making the load rate as constraint can ensure the house electricity safety. In the real-time electricity price environment, this paper put forward a kind of home energy management system dispatch strategy considering load rate, respectively set up minimum electricity costs and minimum carbon emissions as the goal of optimization model, and used the improved genetic algorithm to solve the models. By comparing the simulation results of line load rate, electricity costs and carbon emissions in different models, it shows the strategy can ensure the house electricity using in a safe and optimal way. [ABSTRACT FROM AUTHOR]

The photosynthesis and growth of plants are affected by many environment factors such as temperature, humidity, light, carbon dioxide (CO2) concentration, electrical field and magnetic field. In this paper the effects of high voltage electricity on the photosynthesis of plants are studied experimentally. Two boxes A and B which have positive or negative high voltage electricity are used. Plants can be grown in the garden pot with electricity, and electrical sources are fixed inside the bottom of the boxes. On the top of box a LED (light-emitting diode) bulb is settled as photosynthesis light. We use red light in these experiments. Another box C with no electricity is used for contrast research. First, the static-electrical parameters such as capacitance and current of living tissue of pepper tree leaves are measured while the plants are cultivated with high static-electricity in the boxes. Experimental results show no matter which positive or negative electricity is added on the plants, the capacitances at different points of leaves are lowed by about 0.01 nF, and the currents at different points of plants increase by 1.00-2.00 μA. A high electrical field of several kilovolts per meter is created at the edges of leaves and branches while the plants are cultivated with high voltage electricity. In order to study how the photosynthesis of plants is affected by positive or negative electricity, the CO2 concentrations in the closed boxes A, B and C are measured during the same cultivation time, respectively. The results show that the CO2 concentration in the box B where plants are charged negatively decreases the most. In the experiment of green pineapple the decrease rate of CO2 concentration is 2 μL/(L·min) in A box, 2.35 μL/(L·min) in B box and 1.2 μL/(L·min) in C box. In the experiment of golden diamond tree the decrease rate of CO2 concentration is 0.3 μL/(L·min) in A box, 0.98 μL/(L·min) in B box and 0.12 μL/(L·min) in C box, respectively. In the experiments of pepper tree the decrease rate of CO2 concentration is 1.35, 1.50 and 1.02 μL/(L·min) in the boxes A, B and C respectively during the time from 10:50 to 11:30, and 0.88, 1.73 and 0.53 μL/(L·min) in the boxes A, B and C respectively during the period of 13:10-13:50. The measured results show the similar tendency of CO2 concentration decreasing and the photosynthesis of negatively charged plants is more improved. The photosynthesis of positively charged plants is also improved compared with the plants that are not charged. The chlorophyll fluorescence data of green pineapple are measured. The primary light energy conversion efficiency, yield and photochemical quenching parameter of green pineapple after cultivation with negative electricity are higher than those charged positively or not charged. This experimental study shows that negative high voltage electricity on plants increases the CO2 absorption rates of plants and promotes their photosynthesis greatly. In order to make clear the relationship between the electrical parameters of plants and the transmission of electrical signals in plants triggered by electrical stimuli, many experimental and theoretical works need to be carried out. How the electrical stimuli affect the photosynthesis and respiration of plants will be studied next. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ICs for portable applications need high integration and low supply voltage. Because of high integration, more noise propagates onto the supplies. So a low voltage, high PSR LDO is needed. In this paper, such a LDO is proposed. The simulation results show that the PSR is - 78dB at 1 kHz and the minimum supply vohage is 0.9V. [ABSTRACT FROM AUTHOR]