We report a comprehensive process for designing and prototyping new and optimized optical trapping systems. A combination of traditional lens design strategies, simulation of optical forces, and high-end ultraprecision machining of optical free-form surfaces is applied to the realization of a highly specialized optical trapping system. The resulting compact and lightweight optical modules potentially open new classes of applications for optical manipulation. As an example we present a customized 3D trapping module made of a single piece of polymethylmethacrylate, with a large working distance of 650 μm.
This paper presents a novel sequence detection algorithm well-suited for data transmission and wake-up receiver addressing in FSK-based narrowband power line communication applications, where the communication channel is characterized by non-white noise, interferers and frequency-selective signal attenuation. The algorithm is discussed in detail, verified by Monte Carlo simulations and compared to state of the art solutions. Furthermore, it is shown that, in an equivalent noise scenario, the proposed algorithm offers a performance comparable to the state of the art technologies with a significantly lower algorithmic complexity
To tackle the impacts of the intermittent infeed of renewable energies, power system management evolves from a centralized to a decentralized grid control strategy, thereby micro-grids are getting more relevant, especially regarding the self-sustaining energy supply of building complexes and premises. For control of the power flow and for energy management purposes within micro-grids, the exchange of information between the components is essential. A range of several hundred meters, data rates of several hundred kbits, and low latency are key requirements in widespread premises. This paper addresses the investigation and development of a novel communication technology that is highly suitable for a robust and interoperable micro-grid control and local energy management. The introduced fieldbus protocol is based on RS-485 and an adaption of the IEEE Std. 802.15.4 in combination with the modern Internet of Things protocols
Cyber security is an important issue in modern smart grid technology. As the smart grid is literally a network of networks, manifold potential vulnerabilities appear that allow privacy- and security-attacks within the whole energy chain, e.g. generation, transmission, distribution and consumption. Therefore, in order to achieve full customer acceptance and to ensure the stability of the current supply, all components of a smart grid communication network have to be highly secure and meet challenging privacy requirements. Scores of scientif c and governmental efforts exist to make smart grid technology secure with respect to potential cyber-attacks. Nevertheless, standardization is mandatory to ensure sophisticated security mechanisms through the whole network. This paper focuses on the work of smart grid security aspects on the low voltage segment within the German power grid. Evolving security standards are discussed against the background of potential vulnerabilities and it is emphasized, where additional effort is necessary to ensure privacy and security in the smart grid
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