175 research outputs found
Economic valuation of irrigation water under a major irrigation scheme (Gal Oya) in eastern Sri Lanka
The objective of this study was to estimate the economic value of irrigation water used in a crop farm (paddy and chilies) using a Linear Programming approach in the Senanayake Samudra (Gal-Oya Irrigation Scheme) Right Bank System area in the Ampara District.Length: pp.89-94Irrigation schemesIrrigation waterPricingModels
A User Satisfaction Study of the London Congestion Charging e-Service
This research seeks to measure citizen satisfaction with the electronic London Congestion Charging (LCC)
payment system offered by Transport For London (TFL) in the United Kingdom (UK). The paper reports
on the findings of a survey of 500 users of the TFL LCC online payment system. Satisfaction is measured
using the four dimensions from the COBRA framework 0that comprise the cost, opportunity, benefits and
risk assessment constructs. The results show that most citizens using the LCC electronic service are
satisfied with the service and that the service meets their essential needs. The paper also presents the
results of qualitative feedback obtained from the participants that can be used to determine the areas that
need further improvement in the current electronic LCC electronic-service (e-service) system and
potential influences on user satisfaction
What is the Brillouin Zone of an Anisotropic Photonic Crystal?
The concept of the Brillouin zone (BZ) in relation to a photonic crystal
fabricated in an optically anisotropic material is explored both experimentally
and theoretically. In experiment, we used femtosecond laser pulses to excite
THz polaritons and image their propagation in lithium niobate and lithium
tantalate photonic crystal (PhC) slabs. We directly measured the dispersion
relation inside PhCs and observed that the lowest bandgap expected to form at
the BZ boundary forms inside the BZ in the anisotropic lithium niobate PhC. Our
analysis shows that in an anisotropic material the BZ - defined as the
Wigner-Seitz cell in the reciprocal lattice - is no longer bounded by Bragg
planes and thus does not conform to the original definition of the BZ by
Brillouin. We construct an alternative Brillouin zone defined by Bragg planes
and show its utility in identifying features of the dispersion bands. We show
that for an anisotropic 2D PhC without dispersion, the Bragg plane BZ can be
constructed by applying the Wigner-Seitz method to a stretched or compressed
reciprocal lattice. We also show that in the presence of the dispersion in the
underlying material or in a slab waveguide, the Bragg planes are generally
represented by curved surfaces rather than planes. The concept of constructing
a BZ with Bragg planes should prove useful in understanding the formation of
dispersion bands in anisotropic PhCs and in selectively tailoring their optical
properties.Comment: 9 pages, 6 figure
THz generation using a reflective stair-step echelon
We present a novel method for THz generation in lithium niobate using a
reflective stair-step echelon structure. The echelon produces a discretely
tilted pulse front with less angular dispersion compared to a high
groove-density grating. The THz output was characterized using both a 1-lens
and 3-lens imaging system to set the tilt angle at room and cryogenic
temperatures. Using broadband 800 nm pulses with a pulse energy of 0.95 mJ and
a pulse duration of 70 fs (24 nm FWHM bandwidth, 39 fs transform limited
width), we produced THz pulses with field strengths as high as 500 kV/cm and
pulse energies as high as 3.1 J. The highest conversion efficiency we
obtained was 0.33%. In addition, we find that the echelon is easily implemented
into an experimental setup for quick alignment and optimization.Comment: 19 pages, 4 figure
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A decision support system for fostering smart energy efficient districts
The role of ICT is becoming prominent in tackling some of the urban societal challenges such as energy
wastage and increasing carbon emissions. In this context, the concept of DAREED aims to deliver an
integrated decision support system (DSS) to drive energy efficiency and low carbon activities at both a
building and district level. The main aim of this paper is to present the technical concept of the Best
Practices recommendation component of the DAREED system. This component seeks to compare and
identify existing best practices to recommend practical actions to various stakeholders (e.g. building
managers, citizens) in order to improve energy performance considering the global needs of a building.
This paper also discusses the context of the three field trial sites (based in UK, Spain and Italy) in which
the DAREED platform along with the best practices tool is to be tested and validated.This work evolved in the context of the project DAREED (Decision support Advisor for innovative
business models and useR engagement for smart Energy Efficient Districts), www.dareed.eu, a project cofunded
by the EC within FP7, Grant agreement no: 609082
A User Satisfaction Study of London's Congestion Charge e-Service: A Citizen Perspective
YesThe importance of evaluation and optimization of electronic government (e-government) services is imperative if the government organisations are to have an effective impact on the success and take-up of the services offered. Transport For London's (TFL) London Congestion Charging (LCC) is one of the innovative electronic services (e-services) introduced by the United Kingdom (UK) government to the citizens. While some studies have addressed the impact of the introduction of the congestion charge there has been a dearth of research performed to address user (citizen) satisfaction of the online LCC system. Therefore, this research seeks to measure the citizen satisfaction of using the LCC online payment system offered by TFL. The citizen satisfaction in this context is measured using the four dimensions from the COBRA framework that comprise the cost, opportunity, benefits and risk assessment constructs. This paper presents the findings of a survey of 500 users of the TFL LCC online payment system. It also reports the qualitative feedback obtained from the participants that can be used to determine the areas that need further improvement in the current LCC e-service and potential influences on user satisfaction
Evidence of sympathetic cooling of Na+ ions by a Na MOT in a hybrid trap
A hybrid ion-neutral trap provides an ideal system to study collisional
dynamics between ions and neutrals. This system provides a general cooling
method that can be applied to optically inaccessible species and can also
potentially cool internal degrees of freedom. The long range polarization
potentials () between ions and neutrals result in large
scattering cross sections at cold temperatures, making the hybrid trap a
favorable system for efficient sympathetic cooling of ions by collisions with
neutral atoms. We present experimental evidence of sympathetic cooling in a
hybrid trap of \ce{Na+} ions, which are closed shell and therefore do not have
a laser induced atomic transition, by equal mass cold Na atoms in a
magneto-optical trap (MOT).Comment: 7 figure
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Dance Expertise modulates behavioural and psychophysiological responses to affective body movement
The present study shows how motor expertise increases sensitivity to affective body movement at the behavioural and physiological level. Nineteen affective movement experts (professional ballet dancers) and twenty-four controls watched 96 video clips of emotionally expressive body movements while they performed an affect rating task (subjective response) and their galvanic skin response was recorded (psychophysiological response). The movements in the clips were either sad or happy, and in half of the trials movements were played in the order in which they are learned (forward presentation), and in the other half, backwards (control condition). Results showed that motor expertise in affective body movement specifically modulated both behavioural and physiological sensitivity to others’ affective body movement, and that this sensitivity is particularly strong when movements are shown in the way they are learnt (forward presentation). The evidence is discussed within current theories of proprioceptive arousal feedback and motor simulation accounts
A case analysis of E-government service delivery through a service chain dimension
YesUnlike e-business few studies have examined how information is generated and exchanged between stakeholders
in an e-government service chain to generate value for citizens. This case study applies the concept of service
chains to empirically explore: a) how internal and external business activities in local government authorities
(LGAs) contribute to electronic service delivery, and b) the impact that internal and external stakeholders have
on these activities. The case study found that the diversity of stakeholders involved and lack of appropriate
mechanisms for information exchange and collaboration are posing the biggest challenges for efficient local egovernment
service delivery
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