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The microstructure, texture, and mechanical properties of the asymmetric welded joint in variable polarity plasma arc (VPPA) welding were studied and discussed in this paper. The asymmetric welded joint was obtained through horizontal welding, where the effect of gravity caused asymmetric material flow. The results showed that the grain size and low angle grain boundary (LAGB) at both sides of the obtained welded joint were asymmetric; the grain size differed by a factor of 1.3. The average grain size of the Base Metal (BM), Lower-weld zone (WZ) and Upper-WZ were 25.73 ± 1.25, 37.87 ± 1.89 and 49.92 ± 2.49 µm, respectively. There is discrepancy between the main textures in both sides of the welded joint. However, the effect of asymmetric metal flow on the weld texture was not significant. The micro-hardness distribution was inhomogeneous, the lowest hardness was observed in regions with larger grain sizes and smaller low angle grain boundary. During tensile strength tests, the specimens fractured at the position with the lowest hardness although it has reached 89.2% of the strength of the BM. Furthermore, the effect of asymmetric metal flow and underlying causes of asymmetric weld properties in VPPA horizontal welding have been discussed and analyzed.

In the field of operation research, linear programming (LP) is the most utilized apparatus for genuine application in various scales. In our genuine circumstances, the manager/decision-makers (DM) face problems to get the optimal solutions and it even sometimes becomes impossible. To overcome these limitations, neutrosophic set theory is presented, which can handle all types of decision, that is, concur, not certain, and differ, which is common in real-world situations. By thinking about these conditions, in this work, we introduced a method for solving neutrosophic multiobjective LP (NMOLP) problems having triangular neutrosophic numbers. In the literature study, there is no method for solving NMOLP problem. Therefore, here we consider a NMOLP problem with mixed constraints, where the parameters are assumed to be triangular neutrosophic numbers (TNNs). So, we propose a method for solving NMOLP problem with the help of linear membership function. After utilizing membership function, the problem is converted into equivalent crisp LP (CrLP) problem and solved by any suitable method which is readily available. To demonstrate the efficiency and accuracy of the proposed method, we consider one classical MOLP problem and solve it. Finally, we conclude that the proposed approach also helps decision-makers to not only know and optimize the most likely situation but also realize the outcomes in the optimistic and pessimistic business situations, so that decision-makers can prepare and take necessary actions for future uncertainty.

The value of trajectory data lies mainly in the spatiotemporal correlation. However, the existing privacy protection methods ignore the spatio-temporal correlation of trajectory data, resulting in a large error in trajectory proportion estimation and Top-K classification. For the privacy of truck trajectory in intelligent logistics, the location and trajectory data perturbation method based on quadtree indexing is proposed, which leverages location generalization and local differential privacy techniques. Our proposed algorithms are suitable for datasets with a large sample space and can protect the trajectory privacy of truck drivers while preserving the strong correlation between adjacent spatio-temporal nodes in the trajectory. The results of simulation on a real trajectory dataset show that the proposed methods not only meet the trajectory privacy requirements of users but also have a good performance in trajectory proportion estimation and Top-K classification.Index Terms-Intelligent logistics; trajectory privacy; spatiotemporal correlation; local differential privacy; quadtree indexing I. INTRODUCTION I NTELLIGENT logistics is an important application of the Industrial Internet of Things (IIoT) and a key part of the whole IIoT system. The development of intelligent logistics is inseparable from the support of communication techniques. The data transmission among the logistics nodes such as trucks, warehouses, workers, and target customers requires high quality communication services, the supporting technology for the evolution of intelligent logistics, such as Internet of Things, cloud computing, big data analytics, artificial intelligence [1], etc., and relies on the communication infrastructure with large capacity, high broadband, low delay, and high reliability. At present, the 5G wireless communications with the characteristics of ultra-high bandwidth, wide

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P Xinqiang MaP 2 P P 1 P Hydro-mechanism and power project outfit technology key lab of Hubei province, WuHan University, P 2 P Northwest electric power design institute, Abstract Steam turbine is a main thermal facility in power plant. There are a lot of items and complicated technology and strict working procedure, and the working schedule is dynamic through the maintenance process. So the issue of how to arrange rationally and adjust working schedule and cut maintenance time and obtain the optimum working schedule is key to improve the maintenance efficiency. This article put forward the maintenance management frame that can be adjusted automatically according to the change of factual engineering schedule in order to achieving maintenance programming. With taking Visual C++6.0 as the basic development kit, the comprehensive utilization database, the system basic kind of storehouse and so on, designed and established an algorithm program of steam turbine maintenance schedule with network chart technology and critical path algorithm based on thorough understanding of the steam turbine overhaul technology flow. The maintenance schedule can be adjusted according to the change of actual working schedule by this optimum computation program, achieving optimization management of the working schedule.T P F . FP T The overhaul management of steam turbine 1.The characteristic of steam turbine overhaulSteam turbine is a facility that has complicated structure and high technology level. Its overhaul This work was supported by the opening fund item of hydromechanism and power project outfit technology key lab of Hubei province, number: 200720801008. affects badly the grid and industry and agriculture produce for the enormous maintenance workload and long maintenance time with the facility capacity increasing. Now the unit is applied in the large generator unit, but the maintenance of steam turbine costs more time and the maintenance technology is difficult, so it becomes the main problem that affects the whole maintenance time in routine maintenance. It requires to adapting the scientific management method and arranges rationally each working procedure for the strict working procedure and intervolved of each type of work in steam turbine overhaul, in order to obtain the optimum overhaul schedule.The key of controlling overhaul time is how to reduce the waiting time of every working procedure after demanding the working procedure The main phases of steam turbine overhaulThe overhaul process of steam turbine is composed of five phases which are plan and preparation, start working and disassembly, repair and assembly, testrotation and acceptance and sum-up and improvement [1]. There are different working processes in each phase according to each characteristic.(1) The phase of plan and preparation. The phase is main taking the facility conditions investigation, determining the overhaul items and aims, working out plan and setting down the overhaul measure. The facility defections are spotted and the overhaul can have a definit...

Flexible authorizations are an important problem in current access controls. On the basis of the analysis of access control mechanisms, the flexible features in authorization are proposed and summarized. By several cases, the flexible authorizations are specified using the logic rules, and it is shown that the structural features of logic programs can specify the responding properties of security requirements, at the same time, also determine the semantics computation of the logic programs.