Contactless energy transfer (CET) methods offer great flexibility in the design of complex micro-systems. This paper reports a laser based contactless and selective energy transfer method. A compliant bistable micro-actuator (curved beam of size 25 mm × 1.5 mm × 0.508 mm) is actuated between its two stable positions using the laser heated shape memory alloy (SMA) active elements (size: 3 mm × 1 mm × 0.1 mm). The switching time of the actuator turns out to be 0.5 s for d 0 equal to 700 µm and a laser power of 90 mW (d 0 is half of the total stroke length). The paper also demonstrates the selective energy transfer technique to the SMA active elements by depositing silver based optical filters directly onto the SMA active elements. A successful demonstration is presented for four wavelengths, 532, 660, 785, and 980 nm, using different values of d 0 for the bistable micro-actuator. Finally, a long-term test is performed to highlight the thermo-mechanical effect on the selective addressing capability of the optical filters.

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Objective. To determine if regions with high Medicare expenditures in a given setting remain high cost over time. Data Sources/Study Setting. One hundred percent of national Medicare Parts A and B fee-for-service beneficiary claims data and enrollment for 1992-2010. Study Design. Patients are classified into regions. Claims are price-standardized. Risk adjustment is performed at the beneficiary level using the CMS Hierarchical Condition Categories model. Correlation analyses are conducted. Data Collection/Extraction Methods. The data were obtained through a contract with CMS for a study performed for the Institute of Medicine. Principal Findings. High-cost regions in 1992 are likely to remain high cost in 2010. Stability in regional spending is highest in the home health, inpatient hospital, and outpatient hospital settings over this time period. Despite the persistence of a region's relative spending over time, a region's spending levels in all settings except home health tend to regress toward the mean. Conclusions. Relatively high-cost regions tend to remain so over long periods of time, even after controlling for patient health status and geographic price variation, suggesting that the observed effect reflects real differences in practice patterns.

The use of shape memory alloy (SMA) actuators in smart structures is increasing significantly especially in the field of Micro-Electro-Mechanical Systems (MEMS) due to their unique properties. In this work wavelength dependent remote power supply for SMA is presented to avoid electrical cables from the working area of the structure and to demonstrate the selective addressing of a high number of micro-actuators placed in a small space. Low power (∼100 mW) continuous mode laser diodes are used as remote power supply sources. A thermal numerical model is presented to visualize the temperature evolution in a Nitinol sample (3 mm × 1 mm × 100 μm) irradiated by 785 nm laser source. A series of experiments are performed to validate the modelling results, to estimate the response time under different loadings (15 g and 20 g) and to demonstrate the wavelength dependent deformation in SMA samples for selective addressing which is realized by depositing thin layers having specific optical filtering properties directly over the SMA sample and using laser diode sources with different wavelengths (785 nm and 658 nm).

In this work, a bistable curved-beam is actuated between its two stable states using the force generated by optically controlled SMA elements. Two Shape Memory Alloy (SMA) elements are used for this purpose forming an antagonistic pair. Two laser sources (wavelength equals to 785 nm and 658 nm) are used to heat the SMA active elements in order to induce the martensite to austenite phase transformation in the SMA. The force generated by the SMA sample (3 mm x 1 mm x 100 μm) is measured experimentally using a miniature force sensor which comes out to be 706 mN for 100 mW laser power value. The bistable curved-beam is designed according to these force measurements. At the end, experimental demonstration of the proposed actuation technique is presented.