817 research outputs found
Design patterns for work and organization structures to improve performance in Public-Private Partnerships
Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, 2018.Cataloged from PDF version of thesis.Includes bibliographical references (pages 91-94).A project planning phase is critical to the success of the Public-Private Partnership (PPP) project. The design of a work breakdown structure (WBS) is an essential and effective task in the planning phase. The purpose of this paper is to introduce a new way of designing a WBS through the Work Breakdown Design Pattern Generator (WBDPG). Compared to conventional ways of creating a WBS, the WBDPG helps to design a WBS based on the ability to compare the alternatives and their potential benefits. The core hypothesis of this research is that a well-designed and thus better performing - WBS should increase alignment between situational project requirements and the project's product breakdown structure (PBS) or organizational breakdown structure (OBS). In order to consider this alignment and tradeoffs, a method is proposed which uses morphological and domain mapping matrices to conduct a tradespace and scenario analyses. With this "generator" method, combinations of different breakdown rules across several layers of hierarchy lead to predicted varying levels of performance of the project. For example, a WBS made of functional breakdown rules shows high alignment with the PBS, thus such projects result in better performance related to the product structure. In contrast, a WBS driven by resource breakdown rules aligns highly with the OBS, resulting in high performance related to the organizational structure. In a case where locational difference has a big impact on the project, a WBS made of geographical breakdown rules is likely to lead to better performance. The research concludes that the Work Breakdown Design Pattern Generator can forecast different performance given WBSs designed through different combinations of breakdown rules, and resulting variation in alignment across breakdown structures. Given that PPP projects are often complex, with large-scale and many stakeholders, the method demonstrates a way that structural alternatives can be generated so that the various partners in dialogue can shape their work approach efficiency in the early phase. The research has several limitations and opportunities for extension. In this paper, the organization structure and the product structure are assumed as given. Also, any refinement or change loops to the WBS during the project were not considered.by Young-Min, Kwon.S.M. in Engineering and Managemen
A self-tuning mechanism in (3+p)d gravity-scalar theory
We present a new type of self-tuning mechanism for ()d brane world
models in the framework of gravity-scalar theory. This new type of self-tuning
mechanism exhibits a remarkable feature. In the limit , being
the string coupling, the geometry of bulk spacetime remains virtually unchanged
by an introduction of the Standard Model(SM)-brane, and consequently it is
virtually unaffected by quantum fluctuations of SM fields with support on the
SM-brane. Such a feature can be obtained by introducing Neveu-Schwarz(NS)-brane
as a background brane on which our SM-brane is to be set. Indeed, field
equations naturally suggest the existence of the background NS-brane. Among the
given such models, of the most interest is the case with , where
represents the bulk cosmological constant. This model contains a pair
of coincident branes (of the SM- and the NS-branes), one of which is a
codimension-2 brane placed at the origin of 2d transverse space (), another a codimension-1 brane placed at the edge of .
These two branes are (anti) T-duals of each other, and one of them may be
identified as our SM-brane plus the background NS-brane. In the presence of the
background NS-brane (and in the absence of ), the 2d transverse space
becomes an orbifold with an appropriate deficit angle.
But this is only possible if the ()d Planck scale and the string
scale () are of the same order, which
accords with the hierarchy assumption \cite{1,2,3} that the electroweak scale
is the only short distance scale existing in nature
Standing Spin Wave Resonances in Manganite Films
We report the first observation of spin wave resonances in 110 nm thick films
of LBMO. The spin wave stiffness follows = 47 (1 - 3 \times 10
) meV.Comment: 5 pages LATEX, 3 figures available on request. Submitted to Nature.
Please send all queries to [email protected]
Hamiltonian theory of gaps, masses and polarization in quantum Hall states: full disclosure
I furnish details of the hamiltonian theory of the FQHE developed with Murthy
for the infrared, which I subsequently extended to all distances and apply it
to Jain fractions \nu = p/(2ps + 1). The explicit operator description in terms
of the CF allows one to answer quantitative and qualitative issues, some of
which cannot even be posed otherwise. I compute activation gaps for several
potentials, exhibit their particle hole symmetry, the profiles of charge
density in states with a quasiparticles or hole, (all in closed form) and
compare to results from trial wavefunctions and exact diagonalization. The
Hartree-Fock approximation is used since much of the nonperturbative physics is
built in at tree level. I compare the gaps to experiment and comment on the
rough equality of normalized masses near half and quarter filling. I compute
the critical fields at which the Hall system will jump from one quantized value
of polarization to another, and the polarization and relaxation rates for half
filling as a function of temperature and propose a Korringa like law. After
providing some plausibility arguments, I explore the possibility of describing
several magnetic phenomena in dirty systems with an effective potential, by
extracting a free parameter describing the potential from one data point and
then using it to predict all the others from that sample. This works to the
accuracy typical of this theory (10 -20 percent). I explain why the CF behaves
like free particle in some magnetic experiments when it is not, what exactly
the CF is made of, what one means by its dipole moment, and how the comparison
of theory to experiment must be modified to fit the peculiarities of the
quantized Hall problem
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Unbiased, optimal, and in-betweens: the trade-off in discrete finite impulse response filtering
In this survey, the authors examine the trade-off between the unbiased, optimal, and in-between solutions in finite impulse response (FIR) filtering. Specifically, they refer to linear discrete real-time invariant state-space models with zero mean noise sources having arbitrary covariances (not obligatorily delta shaped) and distributions (not obligatorily Gaussian). They systematically analyse the following batch filtering algorithms: unbiased FIR (UFIR) subject to the unbiasedness condition, optimal FIR (OFIR) which minimises the mean square error (MSE), OFIR with embedded unbiasedness (EU) which minimises the MSE subject to the unbiasedness constraint, and optimal UFIR (OUFIR) which minimises the MSE in the UFIR estimate. Based on extensive investigations of the polynomial and harmonic models, the authors show that the OFIR-EU and OUFIR filters have higher immunity against errors in the noise statistics and better robustness against temporary model uncertainties than the OFIR and Kalman filters
Lowest-Landau-level theory of the quantum Hall effect: the Fermi-liquid-like state
A theory for a Fermi-liquid-like state in a system of charged bosons at
filling factor one is developed, working in the lowest Landau level. The
approach is based on a representation of the problem as fermions with a system
of constraints, introduced by Pasquier and Haldane (unpublished). This makes
the system a gauge theory with gauge algebra W_infty. The low-energy theory is
analyzed based on Hartree-Fock and a corresponding conserving approximation.
This is shown to be equivalent to introducing a gauge field, which at long
wavelengths gives an infinite-coupling U(1) gauge theory, without a
Chern-Simons term. The system is compressible, and the Fermi-liquid properties
are similar, but not identical, to those in the previous U(1) Chern-Simons
fermion theory. The fermions in the theory are effectively neutral but carry a
dipole moment. The density-density response, longitudinal conductivity, and the
current density are considered explicitly.Comment: 32 pages, revtex multicol
A pervasive approach to a real-time intelligent decision support system in intensive medicine
The decision on the most appropriate procedure to provide to the
patients the best healthcare possible is a critical and complex task in Intensive
Care Units (ICU). Clinical Decision Support Systems (CDSS) should deal with
huge amounts of data and online monitoring, analyzing numerous parameters
and providing outputs in a short real-time. Although the advances attained in
this area of knowledge new challenges should be taken into account in future
CDSS developments, principally in ICUs environments. The next generation of
CDSS will be pervasive and ubiquitous providing the doctors with the
appropriate services and information in order to support decisions regardless the
time or the local where they are. Consequently new requirements arise namely
the privacy of data and the security in data access. This paper will present a
pervasive perspective of the decision making process in the context of INTCare
system, an intelligent decision support system for intensive medicine. Three
scenarios are explored using data mining models continuously assessed and
optimized. Some preliminary results are depicted and discussed.Fundação para a Ciência e a Tecnologia (FCT
Deep level emission of ZnO nanoparticles deposited inside UV opal
The temperature-dependent photoluminescence (PL) spectra of zinc oxide (ZnO)
nanocrystals deposited inside the ultraviolet (UV) opal were studied. ZnO was
grown in the voids between FCC packed silicon dioxide spheres using spray
pyrolysis under ultrasonic vibration in the solution containing a zinc nitrate
precursor. The ZnO nanoparticles inside opal matrix with UV photonic band-gap
exhibit suppression of the excitonic emission and enhancement of the deep level
emission. Suppression of the excitonic lines is due to the inhibition of
spontaneous emission, while enhancement and broadening of the DL emission in
the green spectral region is due to Purcell effect. The infiltration of ZnO
inside the photonic crystal may be a useful technique to increase its emission
efficiency in the selected spectral region.Comment: 22 pages, 4 figure
Optical Sum Rule in Finite Bands
In a single finite electronic band the total optical spectral weight or
optical sum carries information on the interactions involved between the charge
carriers as well as on their band structure. It varies with temperature as well
as with impurity scattering. The single band optical sum also bears some
relationship to the charge carrier kinetic energy and, thus, can potentially
provide useful information, particularly on its change as the charge carriers
go from normal to superconducting state. Here we review the considerable
advances that have recently been made in the context of high oxides, both
theoretical and experimental.Comment: Review article accepted for publication in J. Low Temp. Phys. 29
pages, 33 figure
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