Payload IVA training and simulation

The development of a training program for the intravehicular operation of space shuttle payloads is discussed. The priorities for the program are compliance with established training standards, and accommodating changes. Simulation devices are also reviewed

Sustainable land use against the background of a growing wind power industry

Among the measures discussed as remedies for CO2 emissions reduction renewable energies are prominent as they already provide marketable alternatives to fossil fuels. This holds true especially for wind power, which has multiplied more than twelve-fold on the global scale from 4,800 MW to over 59,000 MW between 1995 and 2005. This is the highest growth rate compared to all other sources of renewable energy. However, is this impressive expansion expected to continue in the near future? Although wind power as a clean technology helps to combat global warming and, as a renewable energy reduces the dependency on the supply of exhaustible fossil fuels, it is not without flaws. There are concerns over adverse effects on human beings, on wildlife and on the landscape. This paper discusses the limits for wind power generation and highlights important conflict areas that may roadblock further expansion of wind power and thus its potential to combat global warming. --

Review von Zielmarken, Szenarien und Prognosen der Entwicklung der Windenergienutzung - aufbereitet für Westsachsen und Nordhessen

The paper examines the applicability of available scenarios, prognoses and political target-set-tings of the future development of wind power generation as guiding parameters for the re-search project "FlächEn", which focuses on ecological-economic modelling of a sustainable siting of wind turbines, exemplified for two investigation areas in Germany - Western Saxony and Northern Hesse. The review shows, that wind energy shares in electric power consump-tion for the two areas cannot be, as originally intended in the research project, deduced just like that. As far as energy and climate policy targets are set, these refer to different variables and/or higher aggregated spatial units, e.g., the national level. However, it is not advisable for various reasons to proportionally break down national into sub-national targets 1:1. Moreover, such goals have to be disaggregated not only spatially but also in terms of different energy consuming sectors and policy actions. The second link of the "FlächEn" project, in addition to policy targets are scenarios and prognoses. For this purpose, the review covers 16 references containing relevant scenarios and prognoses with diverse spatial, sectoral and temporal sco-pes. Besides terminological inaccuracies, the review shows that these scenarios and prognoses cover mostly the national and occasionally the state level. Consequently, based on several as-sumptions, they have to be regionalized to fit the two investigation areas. In order to obtain target corridors for the future development of wind power generation in Western Saxony and Northern Hesse in this manner, eventually, only a few of the references evaluated are useful

Automobile Road Vibration Reproduction using Sliding Modes

Sliding mode controllers have a reputation for their robustness against parameter variations, modeling errors and disturbances. They have been successfully applied in several practical situations which demonstrated the potential of sliding mode control for other control problems. However research has mainly been focused on continuous-time sliding mode controllers. In practical applications, where the continuous-time system is sampled by the computer, it is often assumed that the sampling time is sufficiently fast to consider the sampled system as a continuous-time system. This paper aims at providing an overview of the design procedure for discrete-time, output-based, sliding mode controllers, based on discrete-time models. The applicability of these controllers were suggested by the SCOOP project where extra robustness has to be gained by extending the controller setup by the sliding mode feed-back controller

Adaptive switching gain for a discrete-time sliding mode controller

Sliding mode control is a well-known technique capable of making the closed loop system robust with respect to certain kinds of parameter variations and unmodelled dynamics. The sliding mode control law consists of a continuous component which is based on the model knowledge and discontinuous component which is based on the model uncertainty. This paper extends two known adaption laws for the switching gain for continuous-time sliding mode controllers to the multiple input case. Because these adaption laws have some fundamental problems in discrete-time, we introduce a new adaption law specifically designed for discrete-time sliding mode controllers

Sustainable land use against the background of a growing wind power industry

Among the measures discussed as remedies for CO2 emissions reduction renewable energies are prominent as they already provide marketable alternatives to fossil fuels. This holds true especially for wind power, which has multiplied more than twelve-fold on the global scale from 4,800 MW to over 59,000 MW between 1995 and 2005. This is the highest growth rate compared to all other sources of renewable energy. However, is this impressive expansion expected to continue in the near future? Although wind power as a clean technology helps to combat global warming and, as a renewable energy reduces the dependency on the supply of exhaustible fossil fuels, it is not without flaws. There are concerns over adverse effects on human beings, on wildlife and on the landscape. This paper discusses the limits for wind power generation and highlights important conflict areas that may roadblock further expansion of wind power and thus its potential to combat global warming

A modelling approach for allocating land-use in space to maximise social welfare - exemplified on the problem of wind power generation

Land-use conflicts arise if land is scarce, land-use types are mutually exclusive, and vary in their effects with regard to more than one incongruent policy objective. If these effects depend on the spatial location of the land-use measures the conflict can be mediated through an appropriate spatial allocation of land use. An example of this conflict is the welfare-optimal allocation of wind turbines (WT) in a region in order to achieve a given energy target at least social costs. The energy target is motivated by the fact that wind power production is associated with relatively low CO2 emissions and is currently the most efficient source of renewable energy supply. However, it is associated with social costs which comprise energy production costs as well as external costs caused by harmful impacts on humans and biodiversity. We present a modelling approach that combines spatially explicit ecological-economic modelling and choice experiments to determine the welfare-optimal spatial allocation of WT in Western Saxony, Germany. We show that external costs are significant. The welfare-optimal sites are therefore not those with the highest energy output (i.e., lowest production costs). However, they show lower external costs than the most productive sites. A sensitivity analysis reveals that the external costs represent about seven percent of the total costs (production costs plus external costs). Increasing the energy production target increases both production and external costs. The absolute (percentage) increase of production costs is higher (lower) than that of external costs. --choice experiment,ecological-economic modelling,externality,spatial allocation,welfare-optimal,wind power

A modelling approach for allocating land-use in space to maximise social welfare - exemplified on the problem of wind power generation

Land-use conflicts arise if land is scarce, land-use types are mutually exclusive, and vary in their effects with regard to more than one incongruent policy objective. If these effects depend on the spatial location of the land-use measures the conflict can be mediated through an appropriate spatial allocation of land use. An example of this conflict is the welfare-optimal allocation of wind turbines (WT) in a region in order to achieve a given energy target at least social costs. The energy target is motivated by the fact that wind power production is associated with relatively low CO2 emissions and is currently the most efficient source of renewable energy supply. However, it is associated with social costs which comprise energy production costs as well as external costs caused by harmful impacts on humans and biodiversity. We present a modelling approach that combines spatially explicit ecological-economic modelling and choice experiments to determine the welfare-optimal spatial allocation of WT in Western Saxony, Germany. We show that external costs are significant. The welfare-optimal sites are therefore not those with the highest energy output (i.e., lowest production costs). However, they show lower external costs than the most productive sites. A sensitivity analysis reveals that the external costs represent about seven percent of the total costs (production costs plus external costs). Increasing the energy production target increases both production and external costs. The absolute (percentage) increase of production costs is higher (lower) than that of external costs

Co-registered spectral photoacoustic tomography and ultrasonography of breast cancer

Many breast cancer patients receive neoadjuvant treatment to reduce tumor size and enable breast conserving therapy. Most imaging methods used to monitor response to neoadjuvant chemotherapy or hormone therapy depend on overall gross tumor morphology and size measurements, which may not be sensitive or specific, despite tumor response on a cellular level. A more sensitive and specific method of detecting response to therapy might allow earlier adjustments in treatment, and thus result in better outcomes while avoiding unnecessary morbidity. We developed an imaging system that combines spectral photoacoustic tomography and ultrasonography to predict breast neoadjuvant therapeutic response based on blood volume and blood oxygenation contrast. The system consists of a tunable dye laser pumped by a Nd:YAG laser, a commercial ultrasound imaging system (Philips iU22), and a multichannel data acquisition system which displays co-registered photoacoustic and ultrasound images in real time. Early studies demonstrate functional imaging capabilities, such as oxygen saturation and total concentration of hemoglobin, in addition to ultrasonography of tumor morphology. Further study is needed to determine if the co-registered photoacoustic tomography and ultrasonography system may provide an accurate tool to assess treatment efficacy by monitoring tumor response in vivo