295 research outputs found

    Consultants’ Performance on District Assemblies’ Common Fund Projects

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    This study sought to examine the performance of District Assemblies' consultants on Common Fund projects in Ghana. The study employed cross-sectional design and quantitative research approach using a structured questionnaire based on a list of roles of building consultants developed by the Hong Kong Housing Authority to collect the primary data for analysis. The questionnaire was administered by postal survey to 80 District Assemblies (DAs) in Ghana. A system of weights and rating were used to assess the importance of each role and how well the consultants had performed in the same roles. The results showed that under project-related roles, the DA consultants performed very well in quality of recommendations, presentation of reports, design solutions and quality of tender documents, and under general roles they performed very well in effectiveness in surmounting problems, relationship with clients and responsiveness. Major roles requiring improvement include final drawings, presentation of drawings and collection of information during the design phase. The overall performance of the consultants in project-related and general roles was each 62% of maximum score. This indicates that more room exists for continual improvement in performance on project-related and general roles. The findings point to the need for regular performance evaluation of consultants of DAs in order to ensure delivery of quality service and value for money. It is also important to regularly train and educate District Assembly officials involved in recruitment of consultants on why evaluation of consultants is so vital in drawing up contracts. The findings are of value to local government entities seeking to obtain greater satisfaction from their consultants, and also to consultants wishing to improve quality of their service and deliver on their roles. District Assemblies, Consultants, Performance, Common Fund Projects

    The effect of age and font size on reading text on handheld computers

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    Though there have been many studies of computer based text reading, only a few have considered the small screens of handheld computers. This paper presents an investigation into the effect of varying font size between 2 and 16 point on reading text on a handheld computer. By using both older and younger participants the possible effects of age were examined. Reading speed and accuracy were measured and subjective views of participants recorded. Objective results showed that there was little difference in reading performance above 6 point, but subjective comments from participants showed a preference for sizes in the middle range. We therefore suggest, for reading tasks, that designers of interfaces for mobile computers provide fonts in the range of 8-12 point to maximize readability for the widest range of users

    πK\pi K Scattering in Three Flavour ChPT

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    We present the scattering lengths for the πK\pi K processes in the three flavour Chiral Perturbation Theory (ChPT) framework at next-to-next-to-leading order (NNLO). The calculation has been performed analytically but we only include analytical results for the dependence on the low-energy constants (LECs) at NNLO due to the size of the expressions. These results, together with resonance estimates of the NNLO LECs are used to obtain constraints on the Zweig rule suppressed LECs at NLO, L4rL_4^r and L6rL_6^r. Contrary to expectations from NLO order calculations we find them to be compatible with zero. We do a preliminary study of combining the results from ππ\pi\pi scattering, πK\pi K scattering and the scalar form-factors and find only a marginal compatibility with all experimental/dispersive input data.Comment: 23 page

    Quenched QCD with fixed-point and chirally improved fermion

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    In this contribution we present results from quenched QCD simulations with the parameterized fixed-point (FP) and the chirally improved (CI) Dirac operator. Both these operators are approximate solutions of the Ginsparg-Wilson equation and have good chiral properties. We focus our discussion on observables sensitive to chirality. In particular we explore pion masses down to 210 MeV in light hadron spectroscopy, quenched chiral logs, the pion decay constant and the pion scattering length. We discuss finite volume effects, scaling properties of the FP and CI operators and performance issues in their numerical implementation.Comment: Lattice2002(chiral), 17 pages, 21 figures, (LaTeX style file espcrc2.sty and AMS style files

    Strongly coupled compact lattice QED with staggered fermions

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    We explore the compact U(1) lattice gauge theory with staggered fermions and gauge field action -\sum_P [\beta \cos(\Theta_P) + \gamma \cos(2\Theta_P)], both for dynamical fermions and in the quenched approximation. (\Theta_P denotes the plaquette angle.) In simulations with dynamical fermions at various \gamma \le -0.2 on 6^4 lattices we find the energy gap at the phase transition of a size comparable to the pure gauge theory for \gamma \le 0 on the same lattice, diminishing with decreasing \gamma. This suggests a second order transition in the thermodynamic limit of the theory with fermions for \gamma below some finite negative value. Studying the theory on large lattices at \gamma = -0.2 in the quenched approximation by means of the equation of state we find non-Gaussian values of the critical exponents associated with the chiral condensate, \beta \simeq 0.32 and \delta \simeq 1.8, and determine the scaling function. Furthermore, we evaluate the meson spectrum and study the PCAC relation.Comment: 21 page

    I=3/2 KπK \pi Scattering in the Nonrelativisitic Quark Potential Model

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    We study I=3/2I=3/2 elastic KπK\pi scattering to Born order using nonrelativistic quark wavefunctions in a constituent-exchange model. This channel is ideal for the study of nonresonant meson-meson scattering amplitudes since s-channel resonances do not contribute significantly. Standard quark model parameters yield good agreement with the measured S- and P-wave phase shifts and with PCAC calculations of the scattering length. The P-wave phase shift is especially interesting because it is nonzero solely due to SU(3)fSU(3)_f symmetry breaking effects, and is found to be in good agreement with experiment given conventional values for the strange and nonstrange constituent quark masses.Comment: 12 pages + 2 postscript figures, Revtex, MIT-CTP-210

    Quenched spectroscopy with fixed-point and chirally improved fermions

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    We present results from quenched spectroscopy calculations with the parametrized fixed-point and the chirally improved Dirac operators. Both these operators are approximate solutions of the Ginsparg-Wilson equation and have good chiral properties. This allows us to work at small quark masses and we explore pseudoscalar-mass to vector-mass ratios down to 0.28. We discuss meson and baryon masses, their scaling properties, finite volume effects and compare our results with recent large scale simulations. We find that the size of quenching artifacts of the masses is strongly correlated with their experimentally observed widths and that the gauge and hadronic scales are consistent.Comment: 66 pages, 33 figures. Published version: minor modifications in the text, references adde

    Comparative Study of full QCD Hadron Spectrum and Static Quark Potential with Improved Actions

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    We investigate effects of action improvement on the light hadron spectrum and the static quark potential in two-flavor QCD for a11a^{-1} \approx 1 GeV and mPS/mV=0.70.9m_{PS}/m_V = 0.7-0.9. We compare a renormalization group improved action with the plaquette action for gluons, and the SW-clover action with the Wilson action for quarks. We find a significant improvement in the hadron spectrum by improving the quark action, while the gluon improvement is crucial for a rotationally invariant static potential. We also explore the region of light quark masses corresponding to mPS/mV0.4m_{PS}/m_V \geq 0.4 on a 2.7 fm lattice using the improved gauge and quark action. A flattening of the potential is not observed up to 2 fm.Comment: LaTeX, 35 pages, 22 eps figures, uses revtex and eps

    Simple Observables from Fat Link Fermion Actions

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    A comparison is made of the (quenched) light hadron spectrum and of simple matrix elements for a hypercubic fermion action (based on a fixed point action) and the clover action, both using fat links, at a lattice spacing a= 0.18 fm. Renormalization constants for the naive and improved vector current and the naive axial current are computed using Ward identities. The renormalization factors are very close to unity, and the spectroscopy of light hadrons and the pseudoscalar and vector decay constants agree well with simulations at smaller lattice spacings (and with experiment).Comment: 22 pages, 12 postscript figures, Revtex plus eps

    Characteristic cohomology of pp-form gauge theories

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    The characteristic cohomology Hchark(d)H^k_{char}(d) for an arbitrary set of free pp-form gauge fields is explicitly worked out in all form degrees k<n1k<n-1, where nn is the spacetime dimension. It is shown that this cohomology is finite-dimensional and completely generated by the forms dual to the field strengths. The gauge invariant characteristic cohomology is also computed. The results are extended to interacting pp-form gauge theories with gauge invariant interactions. Implications for the BRST cohomology are mentioned.Comment: Latex file, no figures, 44 page
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