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Bending angle is an important parameter in multi-pass roll forming. However, in actual manufacturing, there is still a lack of theoretical guidance; hence, rebound defects are commonly observed. In this paper, a bending angle distribution function with an optimized segmented boundary combination is proposed to improve the forming quality and reduce the rebound defects in multi-pass roll forming. For cap-shaped sheets, COPRA, a roll-bending simulation software, is used to investigate the bending angle distribution to optimize the process of cap-shaped roll-bending. Furthermore, the stress and strain distributions in the sheets after each forming pass is analyzed using finite element simulation. The influence law of different bending angle parameters on the quality of sheets is obtained. The finite element simulation is verified by comparing the experimental results of the change law of rebound defects of cap-shaped parts under different bending angle distribution conditions. Based on the segmented boundary combination of bending angle optimization functions, the stress and strain distributions in the sheets during roll-bending forming of the cap-shaped parts are improved, the rebound defects in the bending area are smaller, and the forming quality is better than the other bending angle distribution methods. Published version The authors would like to acknowledge the financial support provided by the National Science Foundation of China (Grant No. 51705295), Shandong Provincial Natural Science Foundation, China (ZR2018MEE022), and Support Program for Youth Innovation Technology in Colleges and Universities of Shandong Province (2019KJB015).

Supplemental Material, sj-pdf-1-jah-10.1177_08982643211000489 for Tobacco Use and Secondhand Smoke Exposure Among Older Adults in India by Lazarous Mbulo, Komanduri S. Murty, Luhua Zhao, Tenecia Smith and Krishna Palipudi in Journal of Aging and Health

Supplemental Material, sj-pdf-1-jah-10.1177_08982643211000489 for Tobacco Use and Secondhand Smoke Exposure Among Older Adults in India by Lazarous Mbulo, Komanduri S. Murty, Luhua Zhao, Tenecia Smith and Krishna Palipudi in Journal of Aging and Health

In view of the important link of vehicle dispatching under the network-type trailer-drop transport strategy of vehicle sharing, this paper uses JAVA to implement the Dijkstra algorithm for the transportation route based on the distance between stations and the demand of freight transportation, so as to find the shortest path, and then through the model of trailer-drop transport, an example is given. The advantages of this vehicle scheduling are analyzed.

Background China’s squatting transportation mode has been continuously developed. A single road hoisting transportation can no longer meet the market demand, and a variety of ways to coexist in the transportation mode is constantly emerging. Objective To study how the stern transport vehicles can complete the dispatching task more efficiently under the conditions of land and sea transportation. Methods analyzes the advantages of the sling transport operation under the condition of land and sea transportation, and establishes the scheduling model of the stern transport vehicle based on land and sea transportation. This paper designs a heuristic algorithm to solve the initial solution of the model. Based on this, combined with the application of simulated annealing The algorithm performs the objective function minimization solution. Results The vehicle scheduling model was verified by practical examples, which proved the practicability of the model and algorithm.

Struts is currently a prevalent Web application development framework based on MVC. It has prominence in the open, large and extensible J2EE-based Web application development. Through combining the actual operation process of E-commerce enterprise with the developed requirement, this paper categorically analyses MVC actual implementation technology, analyses and describes the Struts framework. Finally it gives a demonstrative example of Category manage- ment module, which explains in detail technical implementation to E-Online Shopping System based Struts framework and presents function description of correlative constitution section. By practical application, it shows the system im- proves platform's security and stability.

Near-Source scattering of Rg into S appears to be the primary contributor to the low-frequency Lg. The authors further suggest that the prominent low-frequency spectral null in Lg is due to Rg from a compensated linear vector dipole (CLVD) source, and the low-frequency null in Rg excitation is due to a zero-crossing of the horizontal displacement eigenfunctions. In this study, the mechanism of the excitation of Lg from explosions in layered earth structures are analyzed with theoretical seismograms. Our result shows that the CLVD source generates prominent Lg waves,and the null in the Lg spectra showing remarkably good agreement with those expected from Rg due to a CLVD source. We conclude that the derivative of displacement eigenfunction also takes a key role in the excitation of the null, only zero-crossing of the horizantall displacement eigenfunction can not fully explain it.

These three plays are in a degree involved in the same theme of "waiting". In the broadest sense, the three "waitings" share some conceptions, but in a narrow sense, each waiting in each of the three plays reveals different meanings. This paper discusses the different symbols of the three waitings according to their different cultural backgrounds, explores the same meaning of them on the basis of the same background—in the same world of great lifism, and finally puts forward the rational attitude towards life and the waiting in life.

Braking force distribution coefficient of the axles influences the braking efficiency and the directional stability when the truck is braking. So, reasonable distribution coefficient is very important for traffic safety. Truck generally travels on the road that has a certain range of adhesion conditions. Through calculating the max value of truck brake efficiency in the certain range of adhesion conditions, the paper defines the optimal distribution coefficient, and applies this kind of technique to optimize the braking force distribution coefficient of one kind of FAW truck. It also compares the optimized front and rear curve of utilization adhesion coefficient and severity of braking with the curve before optimization, and analyzes the curves. Finally, the paper conducts road test of a truck. The results show that the technique can improve brake efficiency of truck and have good practical value.