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We observe rogue-wave-like events in red-blood-cell suspensions driven by light scattering and Brownian motion. In contradistinction with results from polystyrene bead suspensions, at high powers, the optical nonlinearity leads to altogether different probability distributions.
With the rapid development of wind power generation technology, how to enhance the capture efficiency of wind turbines is still a challenging problem due to the stochastic characteristics of wind speed. In this paper, an effective wind speed estimation (EWSE) based Maximum Power Point Tracking (MPPT) controller for variable-speed wind turbines (VSWT) is presented. A wind speed estimation model is...
This paper developed a portable red-blue light emitting diode phototherapy system based on the embedded technology. The device took a STM32 microprocessor as its core controller, and red and blue narrow-band LED were used as the light source, which were driven by PT4115. In order to realize the linearly adjustment of light intensity, the STM32 was used for PWM which could achieve continuously adjustable...
In a large-scale indoor environment, a mobile robot needs a proper internal representation of the surrounding environment to carry out its tasks. The metric (grid-based) map and topological map are two common internal representations in robotic realm. In order to take advantage of the two kinds of environmental representations, this paper aims to construct a topological map of an indoor environment...
We used photolithography to fabricate nanoscale grids in proximity to a metal electrode. Such nanoscale grids can be used to mitigate the space charges in the inter-electrode region of a thermionic converter. The nanoscale dimensions together with low fill factor of the grid led to low electron absorption, which was measured experimentally. We further demonstrated space charge mitigation using such...
A compact caesium-atomic-beam microwave clock is investigated at Peking University. The atomic beam is prepared by magnetic state selection and detected, after microwave interrogation, by means of laser-induced fluorescence. Distributed feedback laser diodes are adopted for their large mode-hopping-free ranges, which ensure a care-free long-term operation. Besides, digital servo systems can automatically...
Two experimental techniques (dynamic mechanical analyzer and fiber Bragg grating sensor) are used to characterize the viscoelastic properties of epoxy molding compounds. The creep and stress relaxation tests over a wide temperature range are conducted, and they are used to determine (1) the linear viscoelastic properties based on the thermo-rheological simplicity (master curve, Prony series and shift...
In order to solve the problems about “no bicycle to rent” and “no place to return”, Public bicycle system (PBS) requires rental amount prediction. We build a hybrid short-term rental prediction model of public bicycle by using public bicycle renting record data and environmental characteristic data such as holiday, weather and temperature. By K-means cluster analysis, different rental modes of public...
Computer-system logs often contain high volumes of interesting, useful information, and are an important data source for network security analysis. In this paper, we propose a distributed log stream processing system consisting of three main parts: log collection module, log transmission module and log statistics module. The system uses several open source technologies, not only supports multi-source...
It is necessary to monitor the usage of network resources in the core network, and give the solution to avoiding network congestion problems. Congestion control method in Huawei's routers and switches is analyzed. Based on it, then a real-time network traffic analysis and quality of service management platform was designed. With four-tier architecture and five functional modules, the platform achieves...
8.1. Abstract Transmissible spongiform encephalopathies (TSEs) or prion diseases are neurodegenerative disorders that are invariably fatal in humans and animals. An important component of the infectious agent is a glyco-protein, termed PrPSc, which is derived from a normal cellular protein, termed PrPc. The pathogenic mechanisms of TSEs are not clear, but several factors such as oxidative stress and...
In this paper, we propose an adaptive performance enhancing proxy (A-PEP) based on location information for satellite communication on the move (SOTM) networks. In particular, we propose an adaptive selection algorithm for the transport protocol to maximize the resource efficiency without reducing the goodput in SOTM environments. The simulation results indicate that the proposed A-PEP can maximize...
Network intrusion detection research using KDDCUP 99 dataset often encounters challenges that classifiers could not handle the problem of uneven distribution of attack categories. This is known as imbalanced classification. The Synthetic Minority Over-sampling Technique (SMOTE) can balance the data distribution, but the noisy and boundary data generated by over-sampling can also reduce the classification...
This paper derived a model for the superheated steam temperature based on the open-loop step response. A cascaded control structure based on disturbance observer (DOB) is proposed to accommodate the control difficulties. The simulation results show the great performance improvement compared with the conventional cascaded control structure. This paper is a preliminary research to the cascaded DOB control...
In this paper, an active disturbance rejection control (ADRC) with tracking differentiator (TD) solution is proposed and tested on a certain four operating condition model. The proposed system with a cascaded control scheme is constructed based on a linear Active disturbance rejection controller (LADRC) with parameters optimized under a modified fruit fly algorithm. The tracking performance could...
Against the backdrop that wind power is always abandoned in heat supply period in winter, this paper proposes a novel day-ahead scheduling method and strategy by optimizing indoor temperature based on original heat storage equipment. The simulation of day-ahead optimal dispatch needs to find out the serious abandoned wind power periods. And then the CHP (Combined Heat and Power) units are supposed...
Changes in social networks may reflect an underlying significant events or behaviors within an organization. Detecting these changes effectively and efficiently could have the potential to enable the early warning, and faster response to both positive and negative organizational activities. In this paper, we use a genetic algorithm based back propagation (GABP) neural network model to quantitatively...
We have analyzed the rental trends of public bicycle stations from the real data of PBSS (public bicycle-sharing system) and summarized 3 patterns in the rental trends of public bicycle stations using k-means. The proposed DDIES method in this paper, which has high accuracy in the prediction, is a model based double exponential smoothing model and difference-index smoothing model. The results have...
Recently, we have witnessed a wave of investigations on PT-symmetric optical systems due to the promising features of tunable optical properties given by exceptional points and PT-phase transitions. Although many exotic optical properties have been demonstrated with PT-symmetry, some of these demonstrated properties are commonly believed not special to PT-symmetry. For example, unidirectional zero...
This paper presents a bottleneck identification based differential evolution algorithm for scheduling complex production lines. Operation priority sequences of bottleneck machine groups are determined by the differential evolution algorithm, while operation priority sequences of non-bottleneck machine groups are determined by predefined heuristic rules. The bottleneck identification method is presented...
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