165 research outputs found
Personalisation of internet based business office layout
In current era, the nature of business is ever-changing where communication and interaction between
office workers are encouraged as the scope of work for office is expanding. Traditional offices with
identical cubicles separated with panels are ineffective because not all workers are in the same
activity mode at the same time. Providing and maintaining a comfortable and healthy office
environment is vital consideration in designing an office. The interior layout design parameter involved
are the comfortability of furniture, surrounding temperature, amount of lighting provided, the quality of
indoor air, spatial arrangement, the condition of environment in terms of noise and privacy, and finally
the 2D horizontal and vertical layout. This research seeks to identify the factors of interior layout
design parameter that will affect the productivity and performance of the workers. The research is
conducted using quantitative method. Questionnaire is distributed to the building occupants to
evaluate and obtain their opinion on the satisfaction level of the layout at their workplace. The user
satisfaction and perception on the existing interior layout design are gathered by using a
questionnaire survey. The study proves that the workers are most satisfied with the lighting and least
satisfied with the furniture at their existing interior layout design. The workers from both case studies
agreed that the interior layout design parameter that has the most effect on the productivity is the
environment noise and privacy; while 2D horizontal and vertical layout has the least effect
Significant characteristics of scheduled and condition-based maintenance in office buildings
Sustainability of buildings is one of the main aims in the construction industry. In achieving sustainability, maintenance of buildings and its facilities, which include planning, implementation, and outcome of maintenance activities, becomes an important criterion. This paper aims to identify the significant characteristics of scheduled and condition-based maintenance in office buildings through reviews of relevant literature and a questionnaire survey. The significance of the characteristics was identified through ranking analysis. A semistructured interview was conducted to obtain further details on the characteristics and measures to enhance efficiency of the characteristics. The findings reveal that the dominant characteristics for scheduled maintenance include quality of spare part and material, the level of labor skill and knowledge, and budget allocation for maintenance labor, whereas for condition-based maintenance, the dominant characteristics are the level of manager skill and knowledge, reliability of maintenance data, and financial allocation for the maintenance manager. The study concludes that these dominant characteristics should be considered in the implementation of maintenance strategies
Predictive Maintenance: Monitoring Tools and Equipment
Due to low service quality of maintenance management, high maintenance cost becomes a common issue in building industry of Malaysia. Lack of preventive measure is the problem that resulting poor maintenance performance. So, condition-based maintenance is introduced to improve the maintenance performance. Monitoring tools and equipment is seen as an important factor to ensure the efficiency of condition-based maintenance. So, this paper aims to determine the aspects of monitoring tools and equipment to be concerned in building maintenance, as well as to establish the relationship between the aspects and maintenance cost performance. A quantitative approach is adopted and performed through questionnaire survey. Furthermore, descriptive analysis and correlation analysis are used to analyse the research data. The literature review determines three aspects of monitoring tools and equipment to be considered in maintenance management. Furthermore, the research result demonstrates that the budget allocation for acquisition of monitoring tools and equipment, capability to operate the tools and equipment, as well as availability of the tools and equipment are significantly correlated to the maintenance cost variance. The research recommends the maintenance management to convince the clients or organisation to acquire advanced monitoring tools and equipment for implementation of condition-based maintenance. Besides that, provision of training is encouraged to ensure that the maintenance personnel are able to utilise the tools and equipment
Vortex in a d-wave superconductor at low temperatures
A systematic perturbation theory is developed to describe the magnetic
field-induced subdominant - and -wave order parameters in the mixed
state of a -wave superconductor, enabling us to obtain, within
weak-coupling BCS theory, analytic results for the free energy of a d-wave
superconductor in an applied magnetic field H_{c1}\ltsim H\ll H_{c2} from
down to very low temperatures. Known results for a single isolated vortex
in the Ginzburg-Landau regime are recovered, and the behavior at low
temperatures for the subdominant component is shown to be qualitatively
different. In the case of subdominant pair component, superfluid
velocity gradients and an orbital Zeeman effect are shown to compete in
determining the vortex state, but for realistic field strengths the latter
appears to be irrelevant. On this basis, we argue that recent predictions of a
low-temperature phase transition in connection with recent thermal conductivity
measurements are unlikely to be correct.Comment: 20 RevTEX pages, 6 EPS figures; considerably expanded versio
Quantum cohomology via vicious and osculating walkers
We relate the counting of rational curves intersecting Schubert varieties of the Grassmannian to the counting of certain non-intersecting lattice paths on the cylinder, so-called vicious and osculating walkers. These lattice paths form exactly solvable statistical mechanics models and are obtained from solutions to the Yang–Baxter equation. The eigenvectors of the transfer matrices of these models yield the idempotents of the Verlinde algebra of the gauged u^(n)k -WZNW model. The latter is known to be closely related to the small quantum cohomology ring of the Grassmannian. We establish further that the partition functions of the vicious and osculating walker model are given in terms of Postnikov’s toric Schur functions and can be interpreted as generating functions for Gromov–Witten invariants. We reveal an underlying quantum group structure in terms of Yang–Baxter algebras and use it to give a generating formula for toric Schur functions in terms of divided difference operators which appear in known representations of the nil-Hecke algebra
Improving Sparse Representation-Based Classification Using Local Principal Component Analysis
Sparse representation-based classification (SRC), proposed by Wright et al.,
seeks the sparsest decomposition of a test sample over the dictionary of
training samples, with classification to the most-contributing class. Because
it assumes test samples can be written as linear combinations of their
same-class training samples, the success of SRC depends on the size and
representativeness of the training set. Our proposed classification algorithm
enlarges the training set by using local principal component analysis to
approximate the basis vectors of the tangent hyperplane of the class manifold
at each training sample. The dictionary in SRC is replaced by a local
dictionary that adapts to the test sample and includes training samples and
their corresponding tangent basis vectors. We use a synthetic data set and
three face databases to demonstrate that this method can achieve higher
classification accuracy than SRC in cases of sparse sampling, nonlinear class
manifolds, and stringent dimension reduction.Comment: Published in "Computational Intelligence for Pattern Recognition,"
editors Shyi-Ming Chen and Witold Pedrycz. The original publication is
available at http://www.springerlink.co
Theory of bound polarons in oxide compounds
We present a multilateral theoretical study of bound polarons in oxide
compounds MgO and \alpha-Al_2O_3 (corundum). A continuum theory at arbitrary
electron-phonon coupling is used for calculation of the energies of thermal
dissociation, photoionization (optically induced release of an electron (hole)
from the ground self-consistent state), as well as optical absorption to the
non-relaxed excited states. Unlike the case of free strong-coupling polarons,
where the ratio \kappa of the photoionization energy to the thermal
dissociation energy was shown to be always equal to 3, here this ratio depends
on the Froehlich coupling constant \alpha and the screened Coulomb interaction
strength \beta. Reasonable variation of these two parameters has demonstrated
that the magnitude of \kappa remains usually in the narrow interval from 1 to
2.5. This is in agreement with atomistic calculations and experimental data for
hole O^- polarons bound to the cation vacancy in MgO. The thermal dissociation
energy for the ground self-consistent state and the energy of the optically
induced charge transfer process (hops of a hole between O^{2-} ions) have been
calculated using the quantum-chemical method INDO. Results obtained within the
two approaches for hole O polarons bound by the cation vacancies (V^-) in
MgO and by the Mg^{2+} impurity (V_{Mg}) in corundum are compared to
experimental data and to each other. We discuss a surprising closeness of the
results obtained on the basis of independent models and their agreement with
experiment.Comment: 13 pages, 2 figures, 2 tables, E-mail addresses:
[email protected], [email protected]
Greenberger-Horne-Zeilinger nonlocality for continuous variable systems
As a development of our previous work, this paper is concerned with the
Greenberger-Horne-Zeilinger (GHZ) nonlocality for continuous variable cases.
The discussion is based on the introduction of a pseudospin operator, which has
the same algebra as the Pauli operator, for each of the modes of a light
field. Then the Bell-CHSH (Clauser, Horne, Shimony and Holt) inequality is
presented for the modes, each of which has a continuous degree of freedom.
Following Mermin's argument, it is demonstrated that for -mode
parity-entangled GHZ states (in an infinite-dimensional Hilbert space) of the
light field, the contradictions between quantum mechanics and local realism
grow exponentially with , similarly to the usual -spin cases.Comment: RevTEX; comments are welcomed; new version with minor change
B -> J/psi K^* Decays in QCD Factorization
The hadronic decay B -> J K^* is analyzed within the framework of QCD
factorization. The spin amplitudes A_0, A_\parallel and A_\perp in the
transversity basis and their relative phases are studied using various
different form-factor models for B-K^* transition. The effective parameters
a_2^h for helicity h=0,+,- states receive different nonfactorizable
contributions and hence they are helicity dependent, contrary to naive
factorization where a_2^h are universal and polarization independent. QCD
factorization breaks down even at the twist-2 level for transverse hard
spectator interactions. Although a nontrivial strong phase for the A_\parallel
amplitude can be achieved by adjusting the phase of an infrared divergent
contribution, the present QCD factorization calculation cannot say anything
definite about the phase phi_\parallel. Unlike B -> J/psi K decays, the
longitudinal parameter a_2^0 for B -> J/psi K^* does not receive twist-3
corrections and is not large enough to account for the observed branching ratio
and the fraction of longitudinal polarization. Possible enhancement mechanisms
for a_2^0 are discussed.Comment: 21 pages, 1 figure, a table and a reference added, some typos
correcte
Microbial inoculation to improve plant performance in mine-waste substrates: A test using pigeon pea (Cajanus cajan)
Mining activities alter soil physicochemical and biological properties that are critical for plant establishment. Revitalisation of soil biological properties via microbial inoculations can potentially be adopted to improve vegetation restoration. Here, we evaluate the feasibility of using beneficial microorganisms in the form of commercially available inoculants to enhance plant performance in a non-toxic and infertile mine-waste substrate, using pigeon pea [Cajanus cajan (L) Millsp.] as a test plant. Six treatments were established to investigate the effects of inoculants (Bradyrhizobium spp., microbial mix and uninoculated controls) and water availability (low and moderate) in a factorial design over 6 months. Plant performance was determined by physiological parameters (leaf gas exchange, leaf carbon, nitrogen and stable isotopes) and growth (height and biomass). Plant xylem sap phytohormones were measured to determine the plants' physiological status and effects of inoculation treatments. Results revealed that water had a greater effect on plant growth than inoculation treatments. Inoculation treatments, however, improved some physiological parameters. This study suggests that physical conditions such as soil moisture and nutrient availability may occlude more subtle (direct or interactive) effects of beneficial soil microbes on plant growth and plant condition. Prior knowledge on the biological and physicochemical properties of the soil to be amended, and on plant species-specific responses, would be needed to customise microbial inoculants for maximum benefits to ecological restoration, to support future adoption of this practice
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