4,393 research outputs found
The representation of planning strategies
AbstractAn analysis of strategies, recognizable abstract patterns of planned behavior, highlights the difference between the assumptions that people make about their own planning processes and the representational commitments made in current automated planning systems. This article describes a project to collect and represent strategies on a large scale to identify the representational components of our commonsense understanding of intentional action. Three hundred and seventy-two strategies were collected from ten different planning domains. Each was represented in a pre-formal manner designed to reveal the assumptions that these strategies make concerning the human planning process. The contents of these representations, consisting of nearly one thousand unique concepts, were then collected and organized into forty-eight groups that outline the representational requirements of strategic planning systems
Non-uniform vortex lattices in inhomogeneous rotating Bose-Einstein condensates
We derive a general framework, in terms of elastic theory, for describing the
distortion of the vortex lattice in a rotating Bose-Einstein condensate at
arbitrary rotation speed and determining the dependence of the distortion on
the density inhomogeneity of the system. In the rapidly rotating limit, we
derive the energetics in terms of Landau levels, including excitation to higher
levels; the distortion depends on the excitation of higher levels as well as on
the density gradient. As we show, the dominant effect of higher Landau levels
in a distorted lattice in equilibrium is simply to renormalize the frequency
entering the lowest Landau level condensate wave function -- from the
transverse trap frequency, , to the rotational frequency, , of
the system. Finally, we show how the equilibrium lattice distortion emerges
from elastohydrodynamic theory for inhomogeneous systems.Comment: 6 pages, no figure
Simulation of ultrasonic lamb wave generation, propagation and detection for an air coupled robotic scanner
A computer simulator, to facilitate the design and assessment of a reconfigurable, air-coupled ultrasonic scanner is described and evaluated. The specific scanning system comprises a team of remote sensing agents, in the form of miniature robotic platforms that can reposition non-contact Lamb wave transducers over a plate type of structure, for the purpose of non-destructive evaluation (NDE). The overall objective is to implement reconfigurable array scanning, where transmission and reception are facilitated by different sensing agents which can be organised in a variety of pulse-echo and pitch-catch configurations, with guided waves used to generate data in the form of 2-D and 3-D images. The ability to reconfigure the scanner adaptively requires an understanding of the ultrasonic wave generation, its propagation and interaction with potential defects and boundaries. Transducer behaviour has been simulated using a linear systems approximation, with wave propagation in the structure modelled using the local interaction simulation approach (LISA). Integration of the linear systems and LISA approaches are validated for use in Lamb wave scanning by comparison with both analytic techniques and more computationally intensive commercial finite element/difference codes. Starting with fundamental dispersion data, the paper goes on to describe the simulation of wave propagation and the subsequent interaction with artificial defects and plate boundaries, before presenting a theoretical image obtained from a team of sensing agents based on the current generation of sensors and instrumentation
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Where's the harm? A social marketing approach to reframing 'problem' drinking cultures
Alcohol consumption is often linked to a broad range of social and health problems, yet alcohol also plays a fundamental role in social bonding between people. This paper considers the potential of social marketing to contribute to alcohol consumption reduction and reframe social norms that encourage 'problem' drinking. Based on qualitative research with a variety of Scottish drinkers, the paper emphasises how and why a better understanding of the culturally bound meanings of alcohol (e.g. social identity, self-concept) are of crucial importance to inform any social marketing approach to reframing excessive drinking
Production of a Novel Copper-Binding Ligand by Marine Synechococcus (Cyanobacteria) in Response to Toxic Concentrations of Copper
Marine Synechococcus spp. are extremely sensitive to copper toxicity. Some strains have been shown to produce high-affinity, extracellular ligands of unknown structure which form complexes with free cupric ion. They are also known to produce metallothioneins (MT) in response to cadmium and zinc stress. In the present study, marine Synechococcus PCC 73109 (Agmenellum quadruplicatum BG-1) (Van Baalen) was exposed to three concentrations of CuSO4 for various times. Size exclusion chromatography, atomic absorption spectrophotometry, and reverse phase HPLC were used to isolate an intracellular copper binding ligand of low molecular weight (\u3c 6,500 Da). The ligand was detected after exposure to â„ 8 ÎŒM CuSO4 for 2 hr in BG-11 medium. The intracellular ligand was characterized by electrospray mass spectrometry, amino acid analysis and a universal assay for siderophores. The ligand was not MT, phytochelatin or a siderophore. It is not a peptide but it contains lysine and an unidentified UV 254-absorbing constituent. This compound is a novel copper-binding ligand previously not reported in Synechococcus spp
A derivative method for minimising total cost in heat exchanger networks through optimal area allocation
This paper presents a novel Cost Derivative Method (CDM) for finding the optimal area allocation for a defined Heat Exchanger Network (HEN) structure and stream data, without any stream splits to achieve minimum total cost. Using the Pinch Design Method (PDM) to determine the HEN structure, the approach attempts to add, remove and shift area to exchangers where economic benefits are returned. From the derivation of the method, it is found that the slope of the Δ-NTU relationship for the specific heat exchanger type, in combination with the difference in exchanger inlet temperatures and the overall heat transfer coefficient, are critical to calculating the extra overall duty each incremental area element returns. The approach is able to account for differences in film coefficients, heat exchanger types, flow arrangements, exchanger cost functions, and utility pricing. Incorporated into the method is the newly defined âutility cost savings flow-onâ factor, Ξ, which evaluates downstream effects on utility use and cost that are caused by changing the area of one exchanger. To illustrate the method, the CDM is applied to the distillation example of Gundersen (2000). After applying the new CDM, the total annual cost was reduced by 7.1 % mainly due to 24 % less HEN area for similar heat recovery. Area reduction resulted from one exchanger having a minimum approach temperature (ÎTmin) of 7.7 °C while the other recovery exchangers had larger ÎTmin values. The optimum ÎTmin for the PDM was 12.5 °C. The CDM solution was found to give a comparable minimum total area and cost to two recently published programming HEN synthesis solutions for the same problem without requiring the increased network complexity through multiple stream splits
An evaluation of the implementation of Georgia's Pre-k program: Report of the findings from the Georgia Early Childhood Study (2002-03)
After ten years, Georgia continues to lead the nation in providing full day, publicly subsidized Pre-K to four-year-olds whose parents choose to enroll them. In this report, we assess the extent to which differences in the way Pre-K is implemented affect children's development. Do teachers with higher levels of education have more positive impacts on children's development? Do teaching styles make a difference in terms of children's outcomes by the end of kindergarten? Do children taught using certain curricula fare better than those taught using others? Answers to questions such as these can assist Pre-K administrators in refining Georgia's program and inform those in other states who are developing or expanding their prekindergarten programs
Bridging the Gap: Improving Data Services through Cross-Campus Collaboration
Objective: New York University (NYU) Libraries provide research data services to diverse communities across several campuses. Until recently, they have worked mostly independent of each other. At the main campus, NYU Data Services offers workshops, individual and group consultations, and traveling âroad showsâ on data management to the larger NYU community. At a separate medical center campus, the NYU Health Sciences Library (NYUHSL) supports a data catalog, data management education, and individualized lab support. Finally, Databrary, which is connected to NYUâs Digital Library Technology Services, provides a repository for behavioral and learning science researchers working primarily with video data to store, manage, and share the raw materials of their work with their colleagues. This poster will discuss how these disparate services have worked more closely together by identifying overlap, making connections between service offerings, and sharing knowledge and resources around data. This initiative better enriches the overall mission and strategy of NYU libraries to serve its student and research communities.
Methods: To ensure the better coordination of these data services, we began to hold regular, bi-monthly meetings to discuss strategies for improving data education material, integrating an institutional data catalog created by NYUHSL with main campus systems, and providing data-related outreach to institutional stakeholders. These groups have also collaborated on planning and hosting events on data-related topics including using Databrary, reproducibility in science, and data visualization. Finally, a resource sharing system was instituted across campuses for library faculty to collaborate and improve upon the instructional design of data management education, create outreach materials, and share ongoing project documentation.
Results: The new collaboration between NYU Data Services, NYUHSL and special projects like Databrary has served to break down existing institutional silos to provide better research and educational data services to NYUâs student and research communities. This collaboration has been essential for improving upon existing services, identifying new opportunities to support the data needs of institutional stakeholders, and providing increased levels of outreach. By fostering a better understanding of what data services are available across campuses through this ongoing collaboration, we are better able to identify and support our communitiesâ data needs.
Conclusion: Providing data management, curation, and storage services for a diverse and dynamic research community on campus is a demanding task that requires a distributed effort. Each service fills different gaps for researchers at varying stages of their research practices, though without inter-department communication there was decidedly less impact and reach by everyone. By collaborating and opening a line of communication, we have built a better understanding of how we can interact to provide stronger support to the student and research communities across campuses
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