1,879 research outputs found
Dielectric molding apparatus Patent
Dielectric apparatus for heating, fusing, and hardening of organic matrix to form plastic material into shaped produc
Precipitation detector Patent
Precipitation detector and mechanism for stopping and restarting machinery at initiation and cessation of rai
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The Political Mentoring Toolkit
ESRC Impact Report, to be disseminated to all UK local authorities by Local Government Group
Finite element modelling in integral design strategies of form- and bending-active hybrid structures
This paper discusses form-finding and simulation strategies for form- and bending-active hybrid structures, with practical feedback from two realised projects. Next to some general aspects of computational form-finding approaches with focus on finite element methods (FEM), the influence of changing mechanical properties of elastic beams on the resultant form-found hybrid system will be discussed on an umbrella structure with integrated bendingactive beam elements. Alongside the question of simulation strategies comes the search for a practical design setup to establish an FEM environment that is cross integrating information from various other modelling environments. This is discussed through the case study project M1 where physical form-finding and vector-based spring methods are utilised to generate input data for the FEM simulation
Optical parameters of leaves of seven weed species
The absorption coefficient (k), infinite reflectance (R), and scattering coefficient (s) were tabulated for five wavelengths and analyzed for statistical differences for seven weed species. The wavelengths were: 0.55-micrometer, 0.65-micrometers, 0.85-micrometer, 1.65-micrometers, and 2.20-micrometer. The R of common lambsquarters (Chenopodium album L.), Johnsongrass (Sorghum halepense (L.) Pers.), and annual sowthistle (Sonchus oleraceus L.) leaves at the 0.85-micrometer wavelength were significantly (p=0.05) higher than for sunflower (Heliantus annus L.), ragweed parthenium (Parthenium hysterophorus L.), or London rocket (Sisymbrium irio L.). Annual sowthistle had the largest k value, and Plamer amaranth (Amaranthus palmer S. Wats.) had the smallest k value at the 0.65 approximately chlorophyll absorption wavelength. In general, john-songress, ragweed parthenium, or London rocket had the largest s values among the five wavelengths, wereas annual sowthistle and plamar amaranth were usually lowest
Influence of water availability in the distributions of branched glycerol dialkyl glycerol tetraether in soils of the Iberian Peninsula
The combined application of the MBT (degree of methylation) and CBT (degree
of cyclization) indices, based on the distribution of branched glycerol
dialkyl glycerol tetraethers (brGDGTs) in soils, has been proposed as a
paleoproxy to estimate mean annual temperature (MAT). CBT quantifies the
degree of cyclization of brGDGTs and relates to soil pH. MBT and the
simplified version MBT' quantify the degree of methylation of brGDGTs and
relate to MAT and soil pH. However, other factors such as soil water
availability have also been suggested to influence MBT' and possibly restrict
the combined application of the MBT' and CBT indices as a paleotemperature
proxy. To assess the effect of hydrological conditions on MBT' and CBT, a set
of 23 Iberian Peninsula soil samples, covering a MAT range from
10 to 18 °C and a mean annual precipitation (MAP) range of 405 mm to
1455 mm, was analyzed. We found that the CBT was indeed significantly
correlated with soil pH in our sample set. In contrast, MBT' was not correlated
with MAT but had a significant correlation with the aridity index (AI), a
parameter related to water availability in soils. The AI can explain 50%
of the variation of the MBT', and 70% of the residuals of MAT estimated
with the MBT/CBT proxy as compared to instrumentally measured MAT. We propose
that, in arid settings, where water may be an ecologically limiting factor,
MBT' is influenced by hydrological conditions rather than temperature. Thus,
our results suggest that the combination of MBT' and CBT indices should be
applied with caution in paleotemperature reconstructions in soils from dry
subhumid to hyperarid environments
Packings of 3D stars: stability and structure
© 2016, Springer-Verlag Berlin Heidelberg.We describe a series of experiments involving the creation of cylindrical packings of star-shaped particles, and an exploration of the stability of these packings. The stars cover a broad range of arm sizes and frictional properties. We carried out three different kinds of experiments, all of which involve columns that are prepared by raining star particles one-by-one into hollow cylinders. As an additional part of the protocol, we sometimes vibrated the column before removing the confining cylinder. We rate stability in terms of r, the ratio of the mass of particles that fall off a pile when it collapsed, to the total particle mass. The first experiment involved the intrinsic stability of the column when the confining cylinder was removed. The second kind of experiment involved adding a uniform load to the top of the column, and then determining the collapse properties. A third experiment involved testing stability to tipping of the piles. We find a stability diagram relating the pile height, h, versus pile diameter, (Formula presented.) , where the stable and unstable regimes are separated by a boundary that is roughly a power-law in h versus (Formula presented.) with an exponent that is less than unity. Increasing vibration and friction, particularly the latter, both tend to stabilize piles, while increasing particle size can destabilize the system under certain conditions
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The meaning of my feelings depends on who I am: work-related identifications shape emotion effects in organizations
Theory and research on affect in organizations has mostly approached emotions from a valence perspective, suggesting that positive emotions lead to positive outcomes and negative emotions to negative outcomes for organizations. We propose that cognition resulting from emotional experiences at work cannot be assumed based on emotion valence alone. Instead, building on appraisal theory and social identity theory, we propose that individual responses to discrete emotions in organizations are shaped by, and thus depend on, work-related identifications. We elaborate on this proposition specifically with respect to turnover intentions, theorizing how three discrete emotions - anger, guilt, and pride - differentially affect turnover intentions, depending on two work-related identifications - organizational and occupational identification. A longitudinal study involving 135 pilot instructors reporting emotions, work-related identifications, and turnover intentions over the course of one year provides general support for our proposition. Our theory and findings advance emotion and identity theories by explaining how the effects of emotions are dependent on the psychological context in which they are experienced
Organizational affective tone: a meso perspective on the origins and effects of consistent affect in organizations
Grounded in an open systems perspective, we build and test new theory about how the kinds of industries in which an organization participates influences organizational affective tone and connects to workforce strain. We propose that the more an organization's activities lie in consumer-centric industries (e.g., service, retail), the more positive and less negative the organization's affective tone. We connect consumer-centric industry participation and affective tone by explaining how personnel policies and organizational structure generate and sustain consistent positive and negative affect throughout an organization. Additionally, we examine the effects of organizational affective tone on workforce strain. The results of a survey-based study of 24,015 human resource managers, top management team members, and employees of 161 firms largely support our predictions. We discuss the implications of considering macro contextual factors for understanding affect in organizations
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