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Biomedical and inertial sensors can be used to generate a complete view of complicated physiological changes in a continuous, real-time, and non-invasive manner. As inappropriate on-body attachments may result in errors, the localization information requires calibration. In most previous studies of on-body wearable device localization, the run-time performance was not evaluated in terms of execution time and memory usage. Recently, smartphones have been used as data processing centers and recognition systems for wearable devices. However, the hardware disadvantages of phone devices have a negative effect on both real-time response and system accuracy. In this study, we focus on a high-performance localization system for the mobile environment and propose a memory efficient algorithm that is accelerated by using graphics processing units (GPUs). The algorithm combines a k-nearest neighbor classifier with a support vector machine (SVM)-based decision-maker to refine the classification outcome. This contributes to a faster and more accurate on-body localization for wearable devices. Experiment results demonstrated that the proposed method achieves an accuracy of 92.94%% and is faster than Serial-SVM and GPU-SVM by a factor of 6.81×and 3.87×, respectively. Therefore, the proposed technique can offer a comparable accuracy to SVM-based methods with faster recognition in the mobile environment.

We have developed a novel π-π interaction and dual H-bond concerted control strategy to construct axially chiral naphthylamine heterocycles. With ortho-alkynyl-naphthylamines as the electrophile, indoles and 4-hydroxycoumarins were efficiently employed to construct axially chiral skeletons in good yields and with excellent enantioselectivities (up to 97% enantiomeric excess). Furthermore, the resulting products could be converted to potential squaramides featuring organic catalysts.

A simple and efficient protocol for para-selective C–H amination of 1-naphthylamide derivatives under silver catalysis is described. This reaction system could proceed without the help of directing group and a broad range of substrates were proved to be well tolerated. In addition, control experiments suggested that this reaction might not proceed via a single-electron-transfer process.

Herein, a cascade [3 + 2] annulation of N-aryloxyacetamides with 3-(hetero)arylpropiolic acids affording benzofuran-2(3H)-ones via rhodium(iii)-catalyzed redox-neutral C-H functionalization/isomerization/lactonization using an internal oxidative directing group O-NHAc was achieved. This catalytic system provides a regio- and stereoselective approach to synthesize (Z)-3-(amino(aryl)methylene)benzofuran-2(3H)-ones with exclusive Z configuration selectivity, acceptable yields and good functional group tolerance. Preliminary investigations on ultraviolet-visible and fluorescence behaviors reveal that the annulation products may be applied as a promising fluorescent probe for sensing metal cations, especially for cerium (Ce3+).

We have developed a new synthetic methodology for the rapid construction of cyclopenta[b]naphthalene frameworks from the reaction of propargylic alcohol tethered methylenecyclopropanes with mesyl chloride in the presence of triethylamine through cascade cyclization. The reaction can be performed under mild conditions without the use of transition metals, affording the target products in moderate to good yields, and this cyclization reaction process can be scaled up to a gram-scale synthesis.

An efficient and convenient method has been developed to achieve direct silylation of unactivated remote primary or secondary C(sp3)–H bonds to form C–Si bonds with hexamethyldisilane (HMDS). This method highlights the emerging strategy to transform unactivated methyl or methylene into versatile functional groups in organic synthesis and provides a new method to construct functionalized C–Si bonds for synthetic chemistry.

An efficient and convenient copper-catalyzed method has been developed to achieve direct ortho-C–H/N-H annulation to synthesize phenanthridinones with arynes. This method highlights an emerging strategy to transform inert C–H bonds into versatile functional groups in organic synthesis and provides a new way to synthesize phenanthridinone alkaloids efficiently.

An efficient and convenient method has been developed to achieve direct silylation of unactivated remote primary or secondary C(sp