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In view of the high coupling characteristics between supply and demand sides in regional integrated energy system (RIES), a bi-level interactive decision-making model with multiple agents is proposed. A RIES market with multiple micro integrated energy grid investors and integrated energy customer aggregator is constructed. To study the operation of regional integrated energy market, a multi-agent interactive decision-making model is established, and a bi-level optimization algorithm is used to solve the equilibrium of the model. In the external level, multiple market players participate in non-cooperative game in order to maximize their own profits, reinforcement learning algorithm is adopted to search the optimal bidding strategies. In the internal level, RIES operator clears the market under the constraints of safe and stable operation in RIES, Aiming at maximizing the social welfare in RIES, the interior point method is applied to optimize the clearing results. Finally, a simulation example is given to study the non-cooperative dynamic game process of the proposed model in RIES market.

Safety signs are an important guarantee for the safe operation of a substation. The proper placements of all safety signs in a substation as well as accurate detection and identification of them provide the basis for future defect detection of safety signs. With the use of LABVIEW programming language and MATLAB mathematical software, a method of detecting and recognizing security signs is proposed. First of all, the returned images during the substation inspection will be preprocessed. Then the warning signs will be extracted by color features, and each part of the warning signs will be segmented. Finally, the safety signs will be identified by neural network matching.

Many researchers focus on analysis of social interactions and information propagation, but they do not provide results in an intuitive way that helps people understand easily. In this paper, we aim to visualize social interactions of a group of users and repost propagation in Sina Weibo, and seek for patterns from visualization. We propose a new definition to formulate the relationship between users, which reflects their social interactions. We then visualize the data with the help of multidimensional scaling. The result shows an interesting pattern that social interactions among people change corresponding to significant events. Moreover, we visualize repost propagation of hot weibo posts in Sina Weibo. We discover that repost propagation is explosive in the very first time period. And authorized user accounts are helpful for faster and wider propagation. We later choose another popular repost case to support our finding.

This paper presents the fabrication and characterization of a novel three-dimensional (3D) electret-based micro power generator, which is capable of converting low acceleration (

The paper reports novel design and fabrication of out-of-plane micro airflow sensors based on the hot-wire sensing principle, i.e. gas cooling of electrically-heated wires. Three micro Ti/Au/Cu hot-wire resistors have been fabricated on an out-of-plane Pyrex bubble with height of 300 μm. They are arranged 120 degrees apart on the sidewall of a bubble at height of 100 μm for airflow velocity and direction detection. Air velocity around the out-of-plane bubble structure has been investigated for square and circular package designs. The sensor with axisymmetric circular package has demonstrated the ability to detect velocity (

In this paper, we present the design, fabrication and testing of a micro electret power generator harvesting low frequency and low amplitude vibration sources by the aid of its high quality factor of the device. Conventional polymer, LDPE, is used as electret material in the power generator. Silicon inward S-springs with high spring constant ratios are proposed and incorporated into the device design. Resonant frequency of 97 Hz is achieved in the device testing with small volume of 0.26 cm3. High quality factor of 88.2 of the resonant system enables the power generator to output appreciable current when it harvests the low amplitude harmonic of vibration.

This paper presents the characterization of an energy harvester using a piezoelectric diaphragm as the vibration energy conversion microstructure. The diaphragm containing the spiral electrode operates in the d33 mode. The energy harvesting performance of the diaphragm was characterized. The optimal resistance load and the working frequency were characterized. The resonance tuning and the energy harvesting enhancement due to a proof mass were verified.

This work presents the design, fabrication, and characterization of an energy harvester using a piezoelectric freestanding bulk diaphragm as the sensing element. The diaphragm containing the spiral electrode operates in d 33 mode, which is different from the commonly used d 31 mode diaphragm. The polarization in the diaphragm has a complex distribution that follows to the poling field induced by the double spiral electrode. The matching load impedance and the optimized working frequency were characterized.

As we know, SC-FDMA has been adopted as the uplink access technique in 3GPP LTE standard due to its low PAPR. However, PAPR is still an issue for SC-FDMA, especially with the localized subcarrier allocation scheme. In this paper, we propose a new SLM method with feedback searching, where, ZC (Zandoff-chu) sequence is considered as the initial phase rotation factor, and feedback searching algorithm is utilized for phase sequence update. Simulation results show, PAPR can be reduced efficiently not only in the conventional OFDM system but also in the SC-FDMA system with localized subcarrier allocation method. Furthermore, whatever M-N assignment and modulation format are, more significant PAPR reduction can be achieved in the proposed SLM method compared with conventional SLM.

To further improve system performance of SC-FDMA system which is applied for 3G-LTE uplink standard, in this paper, we specially propose a new cooperative transmission scheme named as Decode-SFBC-Encode-and-Forward (DSF) protocol. The other two traditional types of relay protocols such as Amplify-and-Forward (AF), Decode-and-Forward (DF) are also accounted for performance improvement. The performance of cooperative schemes is compared with non-cooperative SISO system and SFBC-MISO system. Simulation results show, the three relay protocols significantly improve uplink system performance. Furthermore, DSF protocol has better system performance than DF when relay channel condition is not very good. More importantly, in spite of the variation of transmission quality condition, DSF has stable system performance unlike AF and DF which have performance fluctuation.

This paper reports an improved design, fabrication method, testing and analysis of electrostatic/electrets parallel-plate power generator driven by sinusoidal vibration sources having low acceleration (