We demonstrate a monolithic frequency converter incorporating up to four tuning degrees of freedom, three temperature and one strain, allowing resonance of pump and generated wavelengths simultaneous with optimal phase-matching. With a Rb-doped periodically-poled potassium titanyl phosphate (KTP) implementation, we demonstrate efficient continuous-wave second harmonic generation from 795 to 397, with low-power efficiency of 72% and high-power slope efficiency of 4.5%. The measured performance shows good agreement with theoretical modeling of the device. We measure optical bistability effects, and show how they can be used to improve the stability of the output against pump frequency and amplitude variations.
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A rail-guided robotic system is currently being designed for the inspection of ballast water tanks in ships. This robotic system will manipulate sensors toward the interior walls of the tank. In this paper, the influence of rail compliance on the end-effector position error due to ship movement is investigated. An analytical model of the six degrees-of-freedom (DOF) rail stiffness is presented and implemented in a reduced-order analytical frequency response model. This model describes the transfer function between ship acceleration and end-effector position as a function of rail geometry and material properties. Moreover, the influence of the robot compliance is investigated, resulting in design parameters for the robot. The models and calculations are evaluated and compared with a multibody model and prove to be accurate. The analytic models indicate whether or not a proposed robotic system is feasible and if so, optimize rail dimensions, material and robot design. A use-case scenario has been developed which shows that the proposed design will be unlikely to meet the requirements of this robot system design; therefore an alternative design strategy is recommended.
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Instead of using a passive AC power grid for low power applications, this paper describes a smart plug for DC networks that is capable of providing the correct power to a device (up to 100W) and that allows for communication between different plugs and monitoring of energy consumption across the DC network using the Ethernet protocol in conjunction with a signal modulator to adapt the signals to the DC network. The ability to monitor consumption on a device-per-device basis allows for closer monitoring of in-house energy use and provides an easily scalable platform to monitor consumption at a macro level. In order to make this paper attractive for the consumer market and easily integrable with existing consumer devices, a generally compatible solution is needed. To meet these demands and to take advantage of the trend of charging consumer devices through USB, we opted for the recently adapted USB Power Delivery standard. This standard allows devices to communicate with the plug and demand a specific voltage and current needed for the device to operate. The purpose of this paper is to give the reader insight in the development of a proof of concept of the smart DC/DC power plug. 10.1109/DUE.2014.6827761
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