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Summary: In this paper, for the nonholonomic tractor‐trailer system with slipping and skidding, a full state‐triggering implementation of a tracking controller is proposed. Trailers are an important part, and their knowledge is crucial for the safety and control of the vehicle. Without considering system performance constraints, trailers may deviate from their expected position, leading to collisions. Therefore, there is still great interest in addressing the constraint control issues that arise in modern technologies related to network communication. Based on the backstepping method, bounded measurement errors are introduced into the continuous sampling controller considering intra‐vehicle communications. Then two neural networks are used to model unknown dynamics of the system with event sampling inputs, thereby decoupling the design of the control inputs. Finally, we prove the input‐to‐state‐like stability of a continuously sampled controller, and the given event execution control law can ensure the boundedness of measurement errors. Simulation results show the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Energy management system (EMS) is able to coordinate the generation and load to ensure economic and reliable operation and improve performance metrics of microgrids (MGs). However, most the previous studies have focused mainly on the optimal dispatch of the gas turbines and/or energy storage systems inside a normal MG. Very few works have been carried out to address the potential power outage in MGs. In this study, a novel optimal approach in the EMS based on online forecasts is proposed to minimise the system-wide outages of MG, specifically through pre-emptive load shedding. Online distributed generations' output forecasts are updated to predict the state of system and characterise potential upcoming outages. Proper control strategies based on receding horizon methods are introduced in this study. Outage mitigation actions using pre-emptive load shedding are then performed to avoid power outages or minimise the duration of unavoidable outages. The effectiveness of proposed approach can be demonstrated in the presence of various fluctuations, which can be easily integrated in the EMS for both islanded and grid-connected MGs.

An ideal packets pipeline operation scheme was used to set up the path-oriented capacity analytical model in single user multi-channel network. Then, through analyzing the essence of resource competition in multi-channel net- works, the resource constraint model of node contention domain was constructed. Furthermore, the network capacity analytical model in multi-user multi-channel network was set up based on mathematical programming. The centralized and distributed computing methods and applications are studied. The model can describe the path capacity, the network capacity, and the contention relation of the flows in multi-hop multi-channel network. The model is simple, and it can di- rect the network deployment and the design of network protocols.

The catalytic pyrolysis pathways of carbonyl compounds in coal were systematically studied using density functional theory (DFT), with benzaldehyde (C6H5CHO) employed as a coal-based model compound and ZnO, γ-Al2O3, and CaO as catalysts. The results show that the products of both pyrolysis and catalytic pyrolysis are C6H6 and CO. However, the presence of any of the catalysts changes the reaction pathway and reduces the energy barrier, indicating that these catalysts promote C6H5CHO decomposition.The presence of catalysts changes the reaction pathway and the energy barrier decreases in the order Ea (no catalyst)> Ea (CaO)> Ea (γ-Al2O3)> Ea (ZnO), indicating that these catalysts promote C6H5CHO decomposition. [ABSTRACT FROM AUTHOR]

The content of sugar is an important quality index for pears. However, the traditional sugar measurement methods are time-consuming and destructive. In the present study, the authors measured the sugar content of pears using visible and near infrared diffuse reflection spectroscopy. The pretreatment methods of multiplicative scatter correction (MSC), baseline correction, standard normal variate (SNV) transformation, and moving average algorithms were used on the original absorbance spectrum. Results indicate that the absorbance spectra after pretreatment are better than the original absorbance spectra for prediction. Partial least squares (PLS) regression was also used on the original absorbance spectrum and the absorbance spectrum after moving average and baseline correction. It follows that the forecast accuracy of the absorbance spectra after moving average is higher than that of the original absorbance spectra. The models gave good predictions of the sugar content of pears, with corresponding r values of 0.990 8, and standard errors of predictions of 0.019 0.

Objective: To investigate the feasibility of bone marrow mesenchymal stem cells(MSC)with the acellular dermal matrix(ADM) biological patch for the treatment of external anal sphincter injury on the animal models., Methods: Thirty Wistar rats with sphincter injury were randomly divided into three groups. Group A underwent end to end sphincteric repair directly, group B underwent end to end repair and then covered by ADM patch, and group C underwent end to end repair and then covered by ADM which was previously seeded with MSC. After six weeks, the whole ring specimens including anal canal and lower rectum were removed. The hematoxylin and eosin stain and Masson trichrome stain were performed to observe the change of histomorphology., Results: Two weeks later, the majority of rat models presented with moist anus and crissum with loose stools, which indicated that the model was established successfully. Six weeks after repair, in group A and B, the suffusion of fibrous connective tissue and the infiltration of inflammatory cells were observed at the repair site of sphincter. And lots of collagen fiber which was stained into blue deposited dispersedly at the site of repair with no obvious proliferation of capillaries. However, in group C, the blue collagenous fiber which deposited at the sphincter injury site was less than that in groups A and B. Muscle fibers were observed to be stained into red distributed dispersedly at the repair site of sphincter in group C., Conclusions: Transplantation of ADM biological patch rich in bone MSC can partly improve the regeneration of rat injured anal sphincter and lessen the formation of cicatrix.

Objective: To explore the feasibility and functional outcome of antiperistaltic cecoproctostomy in colorectal reconstruction., Methods: Fifty-six patients who underwent antiperistaltic cecoproctostomy were retrospectively studied. Indications for antiperistaltic cecoproctostomy included slow transit constipation(n=44), synchronous colon cancer or colonic polyps(n=5), acute obstructing left colon carcinoma(n=4), and adult megacolon(n=3)., Results: Short-term postoperative complications included wound infections(n=5), 3 lymphatic leakages(n=3), and inflammatory small bowel obstruction(n=1). One month after antiperistaltic cecoproctostomy, the median frequency of daily bowel movement was 4.0(range, 2-6). After a median follow-up of 4 years(range, 1 month to 7 years), the median daily bowel frequency was 2.5(range, 0.5-4.0). Five patients suffered from long-term postoperative complications including small bowel obstruction(n=3), incision hernia(n=1), and mild cecal dilatation(n=1). The mean Wexner incontinence score was 4.2±1.1., Conclusion: Antiperistaltic cecoproctostomy is safe and effective for colorectal reconstruction.

Objectives: To investigate the mechanical properties of bilateral atlantoaxial trans-articular screws and atlas laminar hooks instrumentation with finite element method., Methods: There was a volunteer with age of 28 years old, body height 172 cm, body weight of 60 kg and without cervical deformity by X rays. The ligamentous, nonlinear, three-dimensional finite element models of normal upper cervical spine (C0-3) was developed and validated. The destabilized model with bilateral atlantoaxial trans-articular screws and atlas laminar hooks was evaluated for quasistatic loading., Results: The finite element model of upper cervical spine consists of 229,047 nodes and 152,475 elements, and correlated well with experimental data for all load cases and could be used for experiment. The finite model with bilateral atlantoaxial trans-articular screws and atlas-laminar hooks predicted that the maximum Von Mises Stress was in the region in which screws penetrated the atlantoaxial articular facet. The novel instrumentation resulted in sufficient stability., Conclusion: The bilateral atlantoaxial trans-articular screws and atlas laminar hooks instrumentation is useful and effective for atlantoaxial arthrodesis.