2,612 research outputs found
Progress in community policing
This article examines the development of community-based policing in the\ud
United States and the Netherlands. These two countries were selected because\ud
the United States has been the forerunner of research into the police and one\ud
of the first countries to attempt to introduce on a wide-scale, and conduct\ud
research into community policing. In the Netherlands, the Major Cities Policy,\ud
a governmental approach to addressing the cities' problems provided an\ud
interesting basis for comparison. Policy or operational changes in the police\ud
organization are generally influenced by the political climate and or scientific\ud
research. Both of these factors played a major role in the US. This section\ud
begins with a brief historical view of the factors which brought about changes\ud
within American policing, ultimately resulting in a new concept of community\ud
policing. This is followed by developments which led to community policing or\ud
the concept of the 'neighbourhood teams' (wijkbureaus) in the Netherlands
Quantum theory and chemistry: Two propositions
Two propositions concerning quantum chemistry are proposed. First, it is proposed that the nonrelativistic Schroedinger equation, where the Hamiltonian operator is associated with an assemblage of nuclei and electrons, can never be arranged to yield specific molecules in the chemists' sense. It is argued that this result is a necessary condition if the Schroedinger has relevancy to chemistry. Second, once a system is in a particular state with regard to interactions among its components (the assemblage of nuclei and electrons), it cannot spontaneously eliminate any of those interactions. This leads to a subtle form of irreversibility
Modified Iterative Extended Hueckel. 1: Theory
Iterative Extended Huekel is modified by inclusion of explicit effective internuclear and electronic interactions. The one electron energies are shown to obey a variational principle because of the form of the effective electronic interactions. The modifications permit mimicking of aspects of valence bond theory with the additional feature that the energies associated with valence bond type structures are explicitly calculated. In turn, a hybrid molecular, orbital valence, bond scheme is introduced which incorporates variant total molecular electronic density distributions similar to the way that Iterative Extended Hueckel incorporates atoms
Organic chemistry on Titan
Observations of nonequilibrium phenomena on the Saturn satellite Titan indicate the occurrence of organic chemical evolution. Greenhouse and thermal inversion models of Titan's atmosphere provide environmental constraints within which various pathways for organic chemical synthesis are assessed. Experimental results and theoretical modeling studies suggest that the organic chemistry of the satellite may be dominated by two atmospheric processes: energetic-particle bombardment and photochemistry. Reactions initiated in various levels of the atmosphere by cosmic ray, Saturn wind, and solar wind particle bombardment of a CH4 - N2 atmospheric mixture can account for the C2-hydrocarbons, the UV-visible-absorbing stratospheric haze, and the reddish color of the satellite. Photochemical reactions of CH4 can also account for the presence of C2-hydrocarbons. In the lower Titan atmosphere, photochemical processes will be important if surface temperatures are sufficiently high for gaseous NH3 to exist. Hot H-atom reactions initiated by photo-dissociation of NH3 can couple the chemical reactions of NH3 and CH4 and produce organic matter
Modified Iterative Extended Hueckel. 2: Application to the interaction of Na(+), Na(+)(aq.), Mg(+)-2(aq.) with adenine and thymine
Modified Iterative Extended Hueckel, which includes explicit effective internuclear and electronic interactions, is applied to the study of the energetics of Na(+),Mg(+), Na(+) (aqueous), and Mg(+2) (aqueous) ions approaching various possible binding sites on adenine and thymine. Results for the adenine + ion and thymine + ion are in good qualitative agreement with ab initio work on analogous systems. Energy differences between competing sites are in excellent agreement. Hydration appears to be a critical factor in determining favorable binding sites. That the adenine Nl and N3 sites cannot displace a water molecule from the hydrated cation indicates that they are not favorable binding sites in aqueous media. Of those sites investigated, 04 was the most favorable binding site on the thymine for the bare Na(+). However, the 02 site was the most favorable binding site for either hydrated cation
Memory Structure and Cognitive Maps
A common way to understand memory structures in the cognitive sciences is as a cognitive map.
Cognitive maps are representational systems organized by dimensions shared with physical space. The
appeal to these maps begins literally: as an account of how spatial information is represented and used
to inform spatial navigation. Invocations of cognitive maps, however, are often more ambitious;
cognitive maps are meant to scale up and provide the basis for our more sophisticated memory
capacities. The extension is not meant to be metaphorical, but the way in which these richer mental
structures are supposed to remain map-like is rarely made explicit. Here we investigate this missing
link, asking: how do cognitive maps represent non-spatial information? We begin with a survey of
foundational work on spatial cognitive maps and then provide a comparative review of alternative,
non-spatial representational structures. We then turn to several cutting-edge projects that are engaged
in the task of scaling up cognitive maps so as to accommodate non-spatial information: first, on the
spatial-isometric approach , encoding content that is non-spatial but in some sense isomorphic to
spatial content; second, on the abstraction approach , encoding content that is an abstraction over
first-order spatial information; and third, on the embedding approach , embedding non-spatial
information within a spatial context, a prominent example being the Method-of-Loci. Putting these
cases alongside one another reveals the variety of options available for building cognitive maps, and the
distinctive limitations of each. We conclude by reflecting on where these results take us in terms of
understanding the place of cognitive maps in memory
Sport and austerity in the UK: an insight into Liverpool 2014
The UK’s Comprehensive Spending Review (CSR) in 2010, outlined £81 billion of cuts across government departments by 2014/15. The Conservative-Liberal Democrat reform was premised on the ‘Big Society’ making up for their austere cuts to the state. In this piece, we debate the impact of this on sports development, taking the case study of inner city Liverpool. This example is marked because, on the one hand, it presents cuts to municipal sports facilities which are threatened with closure as a result of shrinking local authority budgets, and on the other this role is partially taken on by an offshoot of Everton Football Club (EFC). The points we debate are: 1) is the change in responsibility from the local authority to a private enterprise, staffed by volunteers, a new turn in sport policy?; and 2) what are the consequences of this on grassroots sport participation
Mode coupling control in a resonant device: application to solid-state ring lasers
A theoretical and experimental investigation of the effects of mode coupling
in a resonant macro- scopic quantum device is achieved in the case of a ring
laser. In particular, we show both analytically and experimentally that such a
device can be used as a rotation sensor provided the effects of mode coupling
are controlled, for example through the use of an additional coupling. A
possible general- ization of this example to the case of another resonant
macroscopic quantum device is discussed
Renormalization Group Approach to Interacting Crumpled Surfaces: The hierarchical recursion
We study the scaling limit of a model of a tethered crumpled D-dimensional
random surface interacting through an exclusion condition with a fixed impurity
in d-dimensional Euclidean space by the methods of Wilson's renormalization
group. In this paper we consider a hierarchical version of the model and we
prove rigorously the existence of the scaling limit and convergence to a
non-Gaussian fixed point for sufficiently
small, where .Comment: 47 pages in simple Latex, PAR-LPTHE 934
- …
