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The era of big data in healthcare is here, and this era will significantly improve medicine and especially oncology. However, traditional machine learning algorithms need to be promoted to solve such large-scale realworld problems due to a large amount of data that needs to be analyzed and the difficulty in solving problems with nonconvex nonlinear settings. We aim to minimize the composite of a smooth nonlinear function and a block-separable nonconvex function on a large number of block variables with inequality constraints. We propose a novel parallel first-order optimization method, called asynchronous block coordinate descent with time perturbation (ATP), which adopts a time perturbation technique that escapes from saddle points and sub-optimal local points. The details of the proposed method are presented with analyses of convergence and iteration complexity properties. Experiments conducted on real-world machine learning problems validate the efficacy of our proposed method. The experimental results demonstrate that time perturbation enables ATP to escape from saddle points and sub-optimal points, providing a promising way to handle nonconvex optimization problems with inequality constraints employing asynchronous block coordinate descent. The asynchronous parallel implementation on shared memory multi-core platforms indicates that the proposed algorithm, ATP, has strong scalability.

In this paper, we combined photolithography, polydimethylsiloxane (PDMS) molding, and UV-forming techniques to fabricate micro-truncated cone arrays. The taper angle of micro-truncated cone arrays was adjusted by changing softbake parameters during photography of photoresist. The fill factor of micro-truncated cone arrays was altered by varying the gap distance between two neighboring cones. In addition, the influences of taper angle and fill factor of micro-truncated cone arrays on efficiency improvement and optical properties of a blue light organic light-emitting diode (OLED) were investigated. The optical properties include spectral shift, CIE coordinates, and viewing-angle-dependent luminance. Experimental results showed that the efficiency of the OLED increased with increasing the fill factor, but decreased with the taper angle of micro-truncated cone arrays. The efficiency of the OLED could be increased up to 42% by attaching the micro-truncated cone array having a fill factor and a taper angle of 94% and 72°, respectively.