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As a key part of PCB design, the ordered escape routing problem is a special NP-hard problem, which has been studied extensively in recent years. In the traditional method, both ILP method and the heuristic algorithms based on ripping-up and rerouting are only applicable to small-scaled pin arrays with fewer pins, which easily lead to time violation. Aiming at the difficulty of large-scale global routing in traditional methods, the iteration-driven method is proposed to solve the global escaping routing problem by linear programming (LP), and to optimize area congestion by reducing capacity. Compared with the latest work, this algorithm can not only escape all pins but also achieve up to 50% times speed up and save 31% wire length.

We aimed to investigate health care needs, health service utilization, and their socio-economic and health-related determinants in people with spinal cord injury (SCI) living in Jiangsu and Sichuan Provinces of China. A total of 1355 participants with SCI living in the community were recruited using a multi-stage stratified random sample and surveyed by telephone or online. Outcomes evaluated included the presence of health care needs, mode of health service utilization, and specific provider types seen within 12 months preceding the survey. The prevalence of healthcare needs was 92%. Needs were higher in Sichuan (98%) as compared to Jiangsu (80%). Of those in need of health care, 38% reported not having utilized care, more in Sichuan (39%) than in Jiangsu (37%). In Jiangsu, inpatient care was more often used than in Sichuan (46% vs. 27%), while in Sichuan outpatient services were utilized more often (33% vs. 17%). On average, 1.6 provider types were seen, with Sichuan reporting fewer different provider types. Considerable differences in the prevalence of health care needs and service utilization patterns were found between provinces, mostly in favour of the economically more developed Jiangsu Province. People with low income, particularly those below the World Bank poverty line for middle-income countries, had increased health care needs but utilized health care less often. Moreover, environmental barriers contributed significantly to unmet health care needs. This implies the necessity to provide better accessible and more affordable rehabilitation services for people with spinal cord injury (SCI) in China such as community-based rehabilitation programming. Policies for alleviation of poverty in the case of SCI including insurance for catastrophic health expenditure should also be reviewed and adapted where applicable. [ABSTRACT FROM AUTHOR]

Legalized routing is an essential part of PCB automatic routing. It solves the problem of wiring conflicts and obtains routing results that comply with the constraints of design rules. Traditional legalized routing problems mostly use trial backtracking methods, but with increasing design complexity and design rules, avoiding wiring conflicts between networks has become increasingly challenging. This paper proposes a legalized routing algorithm based on linear programming to obtain the optimal wiring trajectory under specified topological constraints. First, the corresponding routing model was established based on numerous routing rules, and a routing grid diagram was found using obstacles as grid points. Secondly, a global routing algorithm was used to obtain the estimated wiring path, and integer linear programming was used to realize the mathematical modeling of the legalized routing problem. Finally, a multi-line simultaneous routing strategy was used to design and implement a detailed routing algorithm, optimizing the routing results. We use C++ to complete the coding work and thoroughly test the PCB use cases of different sizes. The experimental results show that our algorithm still maintains a 100% routing success rate, good time performance, and excellent routing quality with large-scale use cases compared with the trial backtracking method. [ABSTRACT FROM AUTHOR]

In the flexible stretch bending of multi-point roller dies process, the deformation of workpiece is mainly driven by clamps. Therefore, the movement track of clamp has a great influence on the forming effect of workpiece. Y-profile, T-profile, and L-profile are taken as the research objects. Simulation and experiments are carried out with two different movement tracks. The influence of the movement tracks on shape error, springback error, and thickness variation of different profiles is discussed. The experimental results of the three profiles processed by the double-sided forming method are consistent with the simulation results, which proves the accuracy of the numerical simulation. The results show that the movement track has a great influence on shape error. Compared with double-sided forming, one-sided forming can effectively reduce springback error. The two different movement tracks have no obvious influence on thickness change. [ABSTRACT FROM AUTHOR]