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In the industrial Internet of things, the generation of tasks is observed to exhibit both continuity and periodicity, along with stringent latency requirements. These characteristics posed challenges to system's cost-efficiency. To address these challenges, a cost minimization resource allocation algorithm based on the urgency of tasks was proposed. By employing a genetic algorithm, the task offloading strategy and the system's resource allocation strategy were optimized. For offloaded tasks, they were scheduled according to their level of urgency. Additionally, the optimal transmission power for each task was calculated to meet latency constraints. Simulation results indicate that the proposed algorithm effectively reduces the overall energy cost of the system.

Objective To investigate the value of 7.0T cardiac magnetic resonance tissue tracking imaging (CMR-TT) in evaluation of cardiac function in rats with early left ventricular remodeling induced by isoproterenol (ISO). Methods Eighteen male healthy specific pathogen-free (SPF) SD rats were randomly divided into control (n=6) and model group (n=12).The rat model of early left ventricular remodeling was established by subcutaneous multipoint injection of 10 mg·kg-1·d-1 ISO solution for 10 d.After modeling, 7.0T CMR cine sequence scans were performed immediately, and the post-processing software CVI42.0 was used to analyze and compare the differences in each left ventricular (LV) function and myocardial strain parameters between the 2 groups of rats.Enzyme-linked immunosorbent assay (ELISA) was performed to detect cardiac troponin Ⅰ(cTn-Ⅰ) and N-terminal B-type natriuretic peptide (NT-pro BNP) levels in right atrial transvenous serum.Pearson correlation analysis was employed to analyze the correlation of left ventricular ejection fraction (LVEF), cTn-Ⅰ and NT-pro BNP levels with each overall myocardial strain parameter of LV. Results The results of imaging, serology and pathology displayed that that the model group showed obvious hypertrophy of the LV myocardium and different damage at each base of the myocardium, resulting in a significant decrease in conventional cardiac function and myocardial strain parameters of LV, which was the symbol of myocardial contractile dysfunction.Compared with the control group, heart mass (HM), heart mass index (HMI), left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular myocardial mass (LVM), left ventricular end-diastolic maximum wall thickness (LVEDTHmax), and left ventricular remodeling index (LVRI) were significantly greater in the rats of the model group (P < 0.05).LVEF, left ventricular global circumferential strain (LVGCS), left ventricular global radial strain (LVGRS), left ventricular global longitudinal strain (LVGLS), LVGRS-Mid-cavity, LVGRS-Apical, LVGCS-Mid-cavity, LVGCS-Apical, LVGLS-Basal, and LVGLS-Apical decreased in different degrees (P < 0.05).The changes in LVEF and cTn-Ⅰ and NT-pro BNP levels were all correlated with the changes in each overall LV myocardial strain parameter. Conclusion CMR-TT can be used to assess cardiac dysfunction in early left ventricular remodeling. x

Herein, a bifunctional nonwoven fabric sorbent containing thioamide and carboxyl groups was synthesized via radiation grafting of acrylonitrile and acrylic acid, followed by modification with sodium sulfide, to selectively recover Au(Ⅲ) from the acidic solution. A polyethylene/polypropylene skin-core-structured nonwoven fabric was used as the substrate. The structure and properties of the sorbent were characterized using infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, energy dispersive spectroscopy, contact angle measurements, X-ray photoelectron spectroscopy, and X-ray diffraction. The adsorption performance of the sorbent was determined through batch adsorption tests. The results indicated that the sorbent exhibited excellent Au‍(Ⅲ) adsorption capacity over a wide pH range (2-7) and demonstrated good selectivity for Au(Ⅲ) in the presence of coexisting metal ions, with selectivity coefficients ranging from 55.00 to 2 429.17 and a gold recovery ratio of 98.5%. The adsorption followed the pseudo-second-order kinetic and Langmuir isotherm models, with an Au(Ⅲ) saturation adsorption capacity of 133.91 mg/g. Au(Ⅲ) could be reduced to crystalline Au(0) during the adsorption process. Moreover, the modified nonwoven fabric could be effectively removed via simple high-temperature treatment, facilitating Au recovery.

A super absorbent polymer (SAP), sodium lignosulfonate (LS)/sodium carboxymethyl cellulose (CMC), was produced from LS and CMC through the irradiation of γ-rays. The effects of the absorbed dose and LS dosage on the water absorption performance of the SAP were investigated. The ultraviolet (UV) resistance of the SAP was also evaluated. The surface morphology, chemical structures, and thermal weightlessness of the SAP were characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, and thermogravimetric analysis, respectively. The optimal conditions for preparing the SAP were as follows: 20 g of CMC, 1 g of LS, 100 g of water, and 15 kGy of absorbed dose. The water absorption capacities of the prepared SAP were 316.1 g/g and 97.1 g/g for deionized water and 0.9% NaCl solution, respectively. Therefore, the water absorption capacity improved with the addition of LS. Moreover, after irradiation with a 365-nm-wavelength UV lamp (16 W) for 15 d, the water absorption capacity (deionized water) of the LS1/CMC SAP was 276 g/g, while that of the LS0/CMC SAP decreased from 259.3 g/g to 176.7 g/g. Finally, the as-prepared SAP exhibited outstanding UV resistance.

The miniature sensor devices and power-efficient Body Area Networks (BANs) for Human Activity Recognition (HAR) have gained increasing interest in different fields, including Daily Life Assistants (DLAs), medical treatment, sports analysis, etc. The HAR systems normally collect data with wearable sensors and implement the computational tasks with a host machine, where real-time transmission and processing of sensor data raise a challenge for both the network and the host machine. This investigation focuses on the hardware/software co-design for optimized sensing and computing of wearable HAR sensor networks. The contributions include (1) design of a miniature wearable sensor node integrating a Micro-Electro-Mechanical System Inertial Measurement Unit (MEMS IMU) with a Bluetooth Low Energy (BLE) in-built Micro-Control Unit (MCU) for unobtrusive wearable sensing; (2) task-centric optimization of the computation by shifting data pre-processing and feature extraction to sensor nodes for in-situ computing, which reduces data transmission and relieves the load of the host machine; (3) optimization and evaluation of classification algorithms Particle Swarm Optimization-based Support Vector Machine (PSO-SVM) and Cross Validation-based K-Nearest Neighbors (CV-KNN) for HAR with the presented techniques. Finally, experimental studies were conducted with two sensor nodes worn on the wrist and elbow to verify the effectiveness of the recognition of 10 virtual handwriting activities, where 10 recruited participants each repeated an activity 5 times. The results demonstrate that the proposed system can implement HAR tasks effectively with an accuracy of 99.20 %.

A novel amidoximated polyethylene nonwoven fabric (PE-g-AO) was successfully prepared by electron beam pre-irradiation grafting with glycidyl methacrylate, followed by reaction induced of ethylenediamine and maleic anhydride, AIBN-initiated polymerization of acrylonitrile, and finally, amidoximation. The chemical structure and morphology of the PE nonwoven fabric before and after modification were characterized by total reflection infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. Adsorption experiment results showed that the adsorption capacity of PE-g-AO for uranium is 71.92 mg/g (U(VI): 20 mg/L; NaF: 2.0 g/L; sorbent dosage: 0.2 g/L; adsorption time: 216 h). When the dosage of adsorbent is 1.0 g/L, the uranyl ions in the solution are basically adsorbed, and the residual uranium concentration is 0.04 mg/L, which meets the national emission standard. Furthermore, the material has a good adsorption selectivity for uranium in a solution containing UO22+, Ca2+, Mg2+, K+, and Na+ ions.

The trap panel structure can give full play to the role of dispersing load and reducing regional stress level. The force transfer characteristics of different types of trap panel structures are analyzed, and the main design points of trap panel structures are summarized. Taking the design of a certain type of aircraft with diagonal brace plate as an example, an improved scheme of diagonal brace plate structure(rigid connection of side brace plate and rear beam frame, full connection of lower side and joint strip plate) is proposed, and compared with the other two design schemes. The results show that the shear stresses of the upper wing and upper cabin of the improved brace plate structure are reduced by 19% and 23%, respectively, and the concentrated load of the rear beam frame is reduced by 67%. The structure has higher efficiency and better stability.

Maritime moving targets continuation observation has important implications to maintain the safety of the navigation barrier. Existing methods either rely on satellite observations, or only rely on UAV observations. Even though the two cooperative observations, it confined to a simple task allocation. They did not solve the problem of maritime moving targets continuation observation. On the basis of difference between satellites observation and UAV observation, we constructed the aerospace collaborative continuation observation model for maritime moving target, and put forward aerospace collaborative continuation observation strategy (ACCOS) to reduce the complexity of solving the model. According to the spatial and temporal characteristics of the task, ACCOS extracted five sub problems to solve the model: Satellite planning, UAV flight plan, UAV observation sequence, target potential area and distribution probability density prediction, UAV path planning. In order to realize the optimization goal of the model, the five sub problems are modelled and solved in turn. Finally, the simulation results show that the proposed method can greatly reduce the average observation period of the target, and effectively solve the problem of the continuous observation of maritime moving target.