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Asymmetric relationships and sustainability of the apparel supply chain: a novel look at asymmetry in supply chains
Development of design allowable data for Celion 6000/LARC-160, graphite/polyimide composite laminates
A design allowables test program was conducted on Celion 6000/LARC-160 graphite polyimide composite to establish material performance over a 116 K (-250 F) to 589 K (600 F) temperature range. Tension, compression, in-plane shear and short beam shear properties were determined for uniaxial, quasi-isotropic and + or - 45 deg laminates. Effects of thermal aging and moisture saturation on mechanical properties were also evaluated. Celion 6000/LARC-160 graphite/polyimide can be considered an acceptable material system for structural applications to 589 K (600 F)
Observation of coasting beam at the HERA Proton--Ring
We present data collected with the HERA-B wire target which prove the
existence of coasting beam at the HERA proton storage ring. The coasting beam
is inherently produced by the proton machine operation and is not dominated by
target effects.Comment: 17 pages (Latex), 12 figures (Enc. Postscript
Transverse beam tail shaping in HERA-p by means of tune modulation
The HERA-B experiment utilizes an internal wire target in the halo of the stored proton beam in order to study CP violation. As operational experience shows, interaction rates tend to be extremely sensitive to tiny orbit jitter amplitudes. In order to stabilize these interaction rates, various methods have been studied to increase diffusion in the transverse proton beam tails without affecting the luminosity at the electron-proton collider experiments ZEUS and H1. Tune modulation was found to be a promising method for this task. The present status of these experiments willbe reported
Systematic Review of Household Water Conservation Interventions Using the InformationāMotivationāBehavioral Skills Model
Increasing droughts and water shortages are intensifying the need for residential water conservation. We identify and classify 24 water conservation studies using the informationāmotivationābehavioral skills (IMB) model by categorizing interventions based on content and water conservation effectiveness. This synthesis revealed several insights. First, all of the interventions used information, motivation, and/or behavioral skills, suggesting that water conservation interventions can be interpreted within the IMB framework. Second, interventions with two or more IMB components led to reductions in water usage, but the average effect sizes between different types of interventions were similar and there was a considerable range around these averages. To the extent that intervention effectiveness is driven by populations lacking specific IMB components, more elicitation research to identify gaps in specific populations could support greater effectiveness. Designing interventions explicitly with the IMB model would facilitate comparability across studies and could support a better understanding of water conservation interventions
Systematic Review of Household Water Conservation Interventions Using the InformationāMotivationāBehavioral Skills Model
Auditory Cortical Detection and Discrimination Correlates with Communicative Significance
Plasticity studies suggest that behavioral relevance can change the cortical processing of trained or conditioned sensory stimuli. However, whether this occurs in the context of natural communication, where stimulus significance is acquired through social interaction, has not been well investigated, perhaps because neural responses to species-specific vocalizations can be difficult to interpret within a systematic framework. The ultrasonic communication system between isolated mouse pups and adult females that either do or do not recognize the calls' significance provides an opportunity to explore this issue. We applied an information-based analysis to multi- and single unit data collected from anesthetized mothers and pup-naĆÆve females to quantify how the communicative significance of pup calls affects their encoding in the auditory cortex. The timing and magnitude of information that cortical responses convey (at a 2-ms resolution) for pup call detection and discrimination was significantly improved in mothers compared to naĆÆve females, most likely because of changes in call frequency encoding. This was not the case for a non-natural sound ensemble outside the mouse vocalization repertoire. The results demonstrate that a sensory cortical change in the timing code for communication sounds is correlated with the vocalizations' behavioral relevance, potentially enhancing functional processing by improving its signal to noise ratio
Sensitivity studies for a space-based methane lidar mission
Methane is the third most important greenhouse gas in the atmosphere after water vapour and carbon dioxide. A major handicap to quantify the emissions at the Earth's surface in order to better understand biosphere-atmosphere exchange processes and potential climate feedbacks is the lack of accurate and global observations of methane. Space-based integrated path differential absorption (IPDA) lidar has potential to fill this gap, and a Methane Remote Lidar Mission (MERLIN) on a small satellite in polar orbit was proposed by DLR and CNES in the frame of a German-French climate monitoring initiative. System simulations are used to identify key performance parameters and to find an advantageous instrument configuration, given the environmental, technological, and budget constraints. The sensitivity studies use representative averages of the atmospheric and surface state to estimate the measurement precision, i.e. the random uncertainty due to instrument noise. Key performance parameters for MERLIN are average laser power, telescope size, orbit height, surface reflectance, and detector noise. A modest-size lidar instrument with 0.45 W average laser power and 0.55 m telescope diameter on a 506 km orbit could provide 50-km averaged methane column measurement along the sub-satellite track with a precision of about 1% over vegetation. The use of a methane absorption trough at 1.65 Ī¼m improves the near-surface measurement sensitivity and vastly relaxes the wavelength stability requirement that was identified as one of the major technological risks in the pre-phase A studies for A-SCOPE, a space-based IPDA lidar for carbon dioxide at the European Space Agency. Minimal humidity and temperature sensitivity at this wavelength position will enable accurate measurements in tropical wetlands, key regions with largely uncertain methane emissions. In contrast to actual passive remote sensors, measurements in Polar Regions will be possible and biases due to aerosol layers and thin ice clouds will be minimised
Passive remote sensing of columnar water vapour content above land surfaces. Part I: Theoretical algorithm development - Part II: Comparison of OVID measurements with radiosonde and DIAL measurements
Various efforts are currently being made to develop remote sensing techniques for high accuracy determination of atmospheric columnar water vapour content above land surfaces. Most of those algorithms are based on radiative transfer calcu lations, however, which have to be verified by spectral airborne or satellite measurements. Initial verification of a new algorithm with the aid of airborne spectral data using the spectrometer OVID (Optical Visible and near Infrared Detector), an airborne water vapour DIAL (Differential Absorption Lidar), an airc;raft humicap sensor and radiosonde data is performed dUIing a flight experiment over Southern Germany. This water vapour algorithm is also dedicated to the MERIS (MEdium Resolution Imaging Spectrometer) in strument on board ESA's satellite ENVISAT which will be launched 1999. Spatial water vapour gradients of &120 = 0.1 g/cm2 over a distance of 100 km were resolved by applying the OVID measurements. The error estimation of the absolute value of the retrieved water vapour contents posesĀ· some problems due to insufficient additional temporal and spatial radiosonde data. However, the principal feasibility has been prove
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