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Complex curved surface parts are integral to the mechanical industry, demanding precise machining techniques. Multi-axis slow tool servo turning has emerged as an efficient method due to its high precision and quality. However, the challenge of severe tool flank interference arises, especially on surfaces with large undulation changes. Conventional methods, such as increasing tool clearance angles or adding extra tool axes, detrimentally affect machining precision and stability. To address this, a non-interference toolpath planning method is proposed for complex surfaces with large undulation changes. The approach begins with establishing geometric models of the single-point diamond turning tool and typical complex surfaces, followed by analyzing the mechanism and evolution of tool flank interference. By considering geometric parameters and vector relationships, the practical tool clearance angles are calculated. And then a criterion for subregion division is introduced and the non-cutting stroke is designed, accounting for the maximal acceleration of machine tool axis. Multi-pass toolpaths are generated to navigate different subregions while avoiding interference by transforming spindle rotation direction. Furthermore, a method is proposed to optimize toolpath stitching in practical machining regions, ensuring continuous and smooth transitions while maintaining machining precision and surface quality. Experimental validation, conducted on a hyperbolic paraboloid surface with large undulation changes, demonstrates a significant reduction in surface roughness (Sa) from 380.503 nm to 75.664 nm—a reduction of 80.115 %. The proposed method not only enhances machining precision and surface quality but also extends tool life and improves working conditions. This research offers vital guidance for non-interference toolpath planning in engineering practice. • A non-interference toolpath planning method with the tool clearance angle is presented. • The non-interference strategy is developed by spindle forward and reverse rotation. • An algorithm of non-cutting stroke design in the interference region is presented. • The non-cutting stroke is optimized smoothly based on the cut-in and cut-out direction. [ABSTRACT FROM AUTHOR]

• Using a Shortcut to Adiabatic (STA) approach to achieve specific high order modes coupling in the waveguide and generate SCG. • Compared to conventional angle tilting edge coupling (<7%) for high order mode, the coupling efficiency over 80 % for specific high order mode from fundamental mode in the broadband spectrum was recorded and demonstrated, confirming the functionality of mode coupling. The observed octave spanning SCG (at level of 30 dB span nearly 600 nm) from TE 10 mode was characterized. • The fabrication tolerance r for waveguide width variations of ± 13 nm is constant with only slight changes (less than 10 %). • This is first time, to our best knowledge, the efficient octave spanning SCG can be generated from specific high order within nonlinear waveguide. Broadband optical sources have been attracting widespread attention because of their remarkable potential for application to quantum technology. One of the major obstacles to realization of such applications is the weak anomalous group velocity dispersion (GVD) of these sources and low coupling efficiency of high order mode for generating supercontinuum generation (SCG). In this work, using a shortcut to adiabaticity (STA) approach, high order modes can be excited selectively with coupling efficiency of more than 80 % to enable octave spanning supercontinuum generation within a waveguide composed of tantalum pentoxide (Ta 2 O 5), which is a high nonlinear refractive index material. The SCG over the range from 650 nm to 1300 nm, which corresponds to one octave, was demonstrated and analyzed when the material was pumped using a femtosecond laser with a center wavelength of 1030 nm. [ABSTRACT FROM AUTHOR]

With the rapid development of the marine economy, the transfer, lease and other transactions of marine use right in China's coastal areas have emerged continuously. At the same time, to promote the effective protection of marine environment and resources, the establishment and reform of marine property rights system has become a very important part. To play the basic role of the market and environmental protection in the utilization of marine resources, it is very important to establish the corresponding property right registration system. In response, the central government has proposed the establishment of a unified registration system for real estate and natural resources nationwide, including in marine areas. Therefore, this study takes China's marine administration as the research object and constructs a conceptual model based on LADM, which serves as an important basis for the subsequent registration system development. Specifically, this study first summarizes the evolution process of China's marine administration system since the founding of China. Secondly, it puts forward the existing marine rights system. Then, based on the LADM standard and the instance-level diagram for marine administration activities, the corresponding LADM-based profile is developed. The core improvement of this model lies in the improved structuring of marine-related rights, restrictions and responsibilities (as well as related source documents), which is an important preparation for the expansion of land information infrastructure to the sea. • The evolution process of marine geo-regulation system since the foundation of new China is summarized. • China's existing marine rights system has been systematically sorted out and refined. • The stratified utilization and adjudication system of China's marine spaces has been conceptually modeled. • An LADM-based marine geo-regulation system is developed, along with a series of supporting instance level diagrams. [ABSTRACT FROM AUTHOR]

In the present study, we used a validated socioeconomic status (SES) index and population-based registry to identify and quantify the impact of SES on access to treatment and overall survival for patients diagnosed with synchronous brain metastases. The Surveillance, Epidemiology, and End Results database was used to extract all patients between 2010 and 2016 with brain metastases at initial presentation. SES was stratified into tertiles and quintiles using the validated Yost index. Multivariable logistic regressions were used to evaluate the impact of demographic, tumor, and socioeconomic covariates on receipt of radiotherapy and chemotherapy. Kaplan-Meier curves were used to estimate survival. Between 2010 and 2016, 35,595 patients presented with brain metastases at the time of primary cancer diagnosis. Most patients received radiation and/or chemotherapy as part of the initial course of their treatment; 71.6% (n = 25,484) were irradiated while 54.4% (n = 19,371) received chemotherapy and 44.9% (n = 15,984) received chemoradiation. Patients in the highest Yost tertile and quintile experienced longer overall survival (P < 0.001). Additionally, multivariable logistic regression revealed that the lowest Yost quintile was significantly less likely to receive either radiation (adjusted OR: 0.82; 95% confidence interval: 0.75–0.89; P < 0.001) or chemotherapy (adjusted OR: 0.62; 95% confidence interval: 0.58–0.67; P < 0.001). In a large, population-based analysis of brain metastasis patients, we found significant differences in treatment access and mild survival differences along socioeconomic strata. More specifically, patients in lower SES tiers suffered worse outcomes and received radiation and chemotherapy less frequently than patients in higher tiers, even after accounting for other tumor- and demographic-related information. [ABSTRACT FROM AUTHOR]