With the development of smart grid, demand-side resources (DSR) will play an increasingly important role in the power balance of supply and demand. In addition, the requirement of a low-carbon smart ...grid means some policy backgrounds, such as carbon emissions trading (CET), should not be ignored. Under these circumstances, it is a good idea to construct a novel unit commitment (UC) model. This paper proposes a model that not only takes advantage of various resources on the demand side, such as electric vehicles, demand response, and distributed generation, but also reflects the effects of CET on generation schedule. Then, an improved particle swarm optimization (IPSO) algorithm is applied to solve the problem. In numerical studies, we analyze the impacts of DSR and CET on the results of UC, respectively. In addition, two meaningful experiments are conducted to study the approaches to allocate emission quotas and the effects of price transmission mechanism.
Aiming at the problem of multi-object detection such as target occlusion and tiny targets in road scenes, this paper proposes an improved YOLOv5 multi-object detection model based on ML-AFP ...(multi-level aggregation feature perception) mechanism. Since tiny targets such as non-motor vehicle and pedestrians are not easily detected, this paper adds a micro target detection layer and a double head mechanism to improve the detection ability of tiny targets. Varifocal loss is used to achieve a more accurate ranking in the process of non-maximum suppression to solve the problem of target occlusion, and this paper also proposes a ML-AFP mechanism. The adaptive fusion of spatial feature information at different scales improves the expression ability of network model features, and improves the detection accuracy of the model as a whole. Our experimental results on multiple challenging datasets such as KITTI, BDD100K, and show that the accuracy, recall rate and mAP value of the proposed model are greatly improved, which solves the problem of multi-object detection in crowded road scenes.
In traditional reservoir simulation methods, the computational domain is often discretized into a grid system (FDM, FVM, FEM, etc.) or a mesh reduction system (point source solution, BEM, meshless ...methods, etc.). This paper develops a connection-based method, which uses connection elements to discretize the computational domain from the flow perspective (named as connection element method, CEM). Based on a generalized finite difference approximation of the pressure diffusion term, each connection element can be characterized by two parameters, namely connection transmissibility and connection volume. The connection transmissibility measures the diffusion capacity of the connection element, and the connection volume measures the volume of the connection element as a geometric entity. Then, the flow equation can be solved directly on the connection elements, by either a fully implicit scheme or a sequential coupled scheme. The fully implicit scheme solves pressures and saturations simultaneously with high accuracy, but the computational cost is very high when the number of connections is large. The sequential coupled scheme calculates the pressure at the nodes of connection elements at the coarse-scale, then solves the fine-scale saturation along the connection elements. In this way, high computational efficiency can be achieved with accuracy. Furthermore, CEM can efficiently and intuitively obtain the possible flow paths between connection elements and reveal the interaction between the nodes by the path-tracking algorithm in graph theory. In addition, CEM with a sequential coupled scheme can be regarded as a physical network framework with small degrees of freedom, as well as a good data-driven framework. In the end, two numerical examples and one field case are presented to demonstrate the superiority of the developed CEM.
The timely identification of differential settlement of track foundations is of great significance for the safety of train operation and the maintenance of track structures. However, traditional ...monitoring techniques cannot meet the requirements of efficient, real-time, and automatic monitoring of track foundation settlement. In order to solve these problems, a real-time identification method based on a gated recurrent unit (GRU) neural network is proposed for the differential settlement of track foundations monitoring. According to parameter sensitivity analysis, the vertical acceleration of the vehicle is selected as the known data fed into the GRU network for differential settlement identification. Then the GRU network is employed to establish the nonlinear relationship between the vertical acceleration of the vehicle and the differential settlement of the track foundation. The results indicate that the longitudinal continuous differential settlement distribution curve of track foundations could be accurately identified with GRU neural network through the real-time vibration response of the vehicle–track. The current method may provide a new means for the real-time and efficient identification of the differential settlement of track foundations.
Traffic load identification for bridges is of great significance for overloaded vehicle control as well as the structural management and maintenance in bridge engineering. Unlike the conventional ...load identification methods that always encounter problems of ill-condition and difficulties in identifying multi parameters simultaneously when solving the motion equations inversely, a novel strategy is proposed based on smart sensing combing intelligent algorithm for real-time traffic load monitoring. An array of lead zirconium titanate sensors is applied to capture the dynamic responses of a beam bridge, while the Long Short-Term Memory (LSTM) neural network is employed to establish the mapping relations between the dynamic responses of the bridge and the traffic load through data mining. The results reveal that, with the real-time strain responses fed into the LSTM network, the speed and magnitude of the moving load may be identified simultaneously with high accuracy when compared to the practically applied load. The current method may facilitate highly efficient identification of the time-varying characteristics of moving loads and may provide a useful tool for long-term traffic load monitoring and traffic control for in-service bridges.
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More and more researches have been carried out recently on Weigh-In-Motion (WIM) technology for solving the traffic safety problems caused by overload. In this article, we aim to study the ...measurement accuracy of the WIM system. Based on the electromechanical theory and elastic half-space method, we establish a theoretical model of multi-layer structure to investigate the correlation between the output voltage of the piezoelectric sensor and the applied force. In addition, we performed cyclic and moving load experiments to verify the accuracy of the analytical calculations. The load magnitude identified by this theoretical model matched the experiments very well, which shows that this model is effective for the WIM system. In addition, we proved that the load frequency is an important factor affecting the measurement accuracy of the sensor, which further enables us to design more suitable sensors for certain use scenarios.
•Treatment with 100 mg/kg SH could alleviate the symptoms of PCM and reduce the presence of plasma cells surrounding the mammary ducts.•SH treatment reduces the expression of Bcl-2.•SH alleviates the ...symptoms of PCM through blockage of IL-6/JAK2/STAT3 signaling.
Plasma cell mastitis (PCM) is a special form of mastitis characterized by periductal inflammation and large-scale plasma cell infiltration. At present, the recurrence rate of PCM after excision is quite high, making PCM a major problem for mammary surgeons. However, no effective drug exists for the treatment of PCM. Numerous studies have demonstrated that Sinomenine hydrochloride (SH) has potent anti-inflammatory and immunoregulatory properties. However, the efficacy and the underlying mechanisms of SH in the treatment of PCM remain unclear. In the present study, we first investigated the therapeutic effects of SH in the PCM mouse model and clarified the possible mechanisms. We found that the levels of plasmocytes and lymphocytes infiltration were alleviated significantly in the 100 mg/kg SH group compared to the control group. In addition, few CD138+ plasma cells were found in the mammary glands of the 100 mg/kg SH group. The levels of Bcl-2 in the 100 mg/kg SH group were dramatically decreased compared with those in the saline group. Mechanistically, we demonstrated that SH inhibited the progression of PCM mainly through downregulating IL-6/JAK2/STAT3 levels. Collectively, our results suggested that SH could inhibit the progression of PCM by suppressing IL-6/JAK2/STAT3 cascades and ultimately achieve a therapeutic effect in PCM. This study provides theoretical support for the clinical application of SH in the treatment of PCM.
Railway tunnel clearance is directly related to the safe operation of trains and upgrading of freight capacity. As more and more railway are put into operation and the operation is continuously ...becoming faster, the railway tunnel clearance inspection should be more precise and efficient. In view of the problems existing in traditional tunnel clearance inspection methods, such as low density, slow speed and a lot of manual operations, this paper proposes a tunnel clearance inspection approach based on 3D point clouds obtained by a mobile laser scanning system (MLS). First, a dynamic coordinate system for railway tunnel clearance inspection has been proposed. A rail line extraction algorithm based on 3D linear fitting is implemented from the segmented point cloud to establish a dynamic clearance coordinate system. Second, a method to seamlessly connect all rail segments based on the railway clearance restrictions, and a seamless rail alignment is formed sequentially from the middle tunnel section to both ends. Finally, based on the rail alignment and the track clearance coordinate system, different types of clearance frames are introduced for intrusion operation with the tunnel section to realize the tunnel clearance inspection. By taking the Shuanghekou Tunnel of the Chengdu-Kunming Railway as an example, when the clearance inspection is carried out by the method mentioned herein, its precision can reach 0.03 m, and difference types of clearances can be effectively calculated. This method has a wide application prospects.
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