The Centers for Medicare & Medicaid Services Incentive Programs promote meaningful use of electronic health records (EHRs), which, among many benefits, allow patients to receive electronic copies of their EHRs and thereby empower them to take a more active role in their health. In the United States, however, 17% population is Hispanic, of which 50% has limited English language skills. To help this population take advantage of their EHRs, we are developing English-Spanish machine translation (MT) systems for EHRs. In this study, we first built an English-Spanish parallel corpus and trained NoteAid Spanish , a statistical MT (SMT) system. Google Translator and Microsoft Bing Translator are two baseline MT systems. In addition, we evaluated hybrid MT systems that first replace medical jargon in EHR notes with lay terms and then translate the notes with SMT systems. Evaluation on a small set of EHR notes, our results show that Google Translator outperformed NoteAid Spanish . The hybrid SMT systems first map medical jargon to lay language. This step improved the translation. A fully implemented hybrid MT system is available at http://www.clinicalnotesaid.org. The English-Spanish parallel-aligned MedlinePlus corpus is available upon request.

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We address the source localization problem by using both time-difference-of-arrival (TDOA) and frequencydifference-of-arrival (FDOA) measurements. We solve this problem in two steps, and in each step, we formulate a nonlinear weighted least squares (WLS) problem followed by a bias reduction scheme. In the first step, we formulate a nonlinear WLS problem using TDOA measurements only, and derive the bias of the WLS solution, which is then used to develop an unbiased WLS solution by subtracting the bias from the WLS solution. In the second step, we formulate another nonlinear WLS problem by combining the results in the first step and the FDOA measurements. To avoid the potential risk of local convergence, this WLS problem is reduced to an approximate WLS problem, for which the globally optimal solution can be obtained. The bias of the WLS solution is also derived and then subtracted from the WLS solution to reduce the bias. Simulation results show that the bias of the proposed method is reduced, and the Cramér-Rao lower bound (CRLB) accuracy is also achieved.

This paper studies direction of arrival (DoA) estimation with an antenna array using sparse signal reconstruction (SSR). Among the existing SSR methods, the sparse covariance fitting based algorithms, which can estimate source power and noise variance naturally, are most promising. Nevertheless, they are either on-grid model based methods whose performance are sensitive to off-grid DoAs or gridless methods which are computationally demanding. In this paper, we propose an off-grid DoA estimation algorithm based on the sparse covariance fitting criterion. We first consider a scenario in which the number of snapshots is larger than the array size. An algorithm is proposed by applying an offgrid model, which takes into account the deviations between the discretized sampling grid and the true DoAs, to the sparse covariance fitting criterion. It estimates the on-grid parameters and the deviations of off-grid DoAs separately and thus is computationally efficient to implement. Then in the case where the number of snapshots is smaller than the array size, we propose to execute the

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