University of Macau

About: University of Macau is a education organization based out in Macao, Macau, China. It is known for research contribution in the topics: Computer science & Population. The organization has 6636 authors who have published 18324 publications receiving 327384 citations. The organization is also known as: UM & UMAC.

Measurement-Based Care Versus Standard Care for Major Depression: A Randomized Controlled Trial With Blind Raters

Abstract: Objective:The authors compared measurement-based care with standard treatment in major depression.Methods:Outpatients with moderate to severe major depression were consecutively randomized to 24 weeks of either measurement-based care (guideline- and rating scale-based decisions; N=61), or standard treatment (clinicians’ choice decisions; N=59). Pharmacotherapy was restricted to paroxetine (20–60 mg/day) or mirtazapine (15–45 mg/day) in both groups. Depressive symptoms were measured with the Hamilton Depression Rating Scale (HAM-D) and the Quick Inventory of Depressive Symptomatology–Self-Report (QIDS-SR). Time to response (a decrease of at least 50% in HAM-D score) and remission (a HAM-D score of 7 or less) were the primary endpoints. Outcomes were evaluated by raters blind to study protocol and treatment.Results:Significantly more patients in the measurement-based care group than in the standard treatment group achieved response (86.9% compared with 62.7%) and remission (73.8% compared with 28.8%). Simil...

A Totally Decoupled Piezo-Driven XYZ Flexure Parallel Micropositioning Stage for Micro/Nanomanipulation

Abstract: This paper reports the design and development processes of a totally decoupled flexure-based XYZ parallel-kinematics micropositioning stage with piezoelectric actuation. The uniqueness of the proposed XYZ stage lies in that it possesses both input and output decoupling properties with integrated displacement amplifiers. The input decoupling is realized by actuation isolation using double compound parallelogram flexures with large transverse stiffness, and the output decoupling is implemented by employing two-dimensional (2-D) compound parallelogram flexures. By simplifying each flexure hinge as a two-degree-of-freedom (2-DOF) compliant joint, analytical models of kinematics, statics, and dynamics of the XYZ stage are established and then validated with finite-element analysis (FEA). The derived models are further adopted for optimal design of the stage through particle swarm optimization (PSO), and a prototype of XYZ stage is fabricated for performance tests. The nonsymmetric hysteresis behavior of the piezo-stage is identified with the modified Prandtl-Ishlinskii (MPI) model, and a control scheme combining the inverse model-based feedforward with feedback control is constructed to compensate the plant nonlinearity and uncertainty. Experimental results reveal that a submicron accuracy 1-D and 3-D positioning can be achieved by the system, which confirms the effectiveness of the proposed mechanism and controller design as well.

A Closed-Form Solution to Retinex with Nonlocal Texture Constraints

Abstract: We propose a method for intrinsic image decomposition based on retinex theory and texture analysis. While most previous methods approach this problem by analyzing local gradient properties, our technique additionally identifies distant pixels with the same reflectance through texture analysis, and uses these nonlocal reflectance constraints to significantly reduce ambiguity in decomposition. We formulate the decomposition problem as the minimization of a quadratic function which incorporates both the retinex constraint and our nonlocal texture constraint. This optimization can be solved in closed form with the standard conjugate gradient algorithm. Extensive experimentation with comparisons to previous techniques validate our method in terms of both decomposition accuracy and runtime efficiency.