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A Total Product System Concept - a case study of the smart (tm) automobile
Increasing demand from consumers plus EU legislation has raised awareness within the automotive production sector of the urgent need to reduce the environmental impacts from the three main stages in vehicle life – car manufacture, car use and end-of life vehicle processing. The paper reviews how the originator and manufacturer of the smart automobile has worked directly with its main system partners to address environmental issues in these three stages while optimizing performance across the parameters of commercial viability. This required the creation of strategic relationships within the supply chain. Overall, this innovative approach is viewed in the context of a total product system. The smart car highlights the following critical areas: use of modularity in product design and production facility layout; emphasis on partner participation from product creation to after-sales; and the use of highly customised build-to-order product system to 'green' the entire supply chain. In particular, the case study compares the process characteristics empoyed at the smart car factory, called 'smartville', with more traditional approaches to vehicle manufacture. It exmaines these issues in a preliminary attempt to establish the actual or potential reduction of environmental impact in the three stages of vehicle life, including the role of main suppliers in this process
Relativistic Kinetics of Phonon Gas in Superfluids
The relativistic kinetic theory of the phonon gas in superfluids is
developed. The technique of the derivation of macroscopic balance equations
from microscopic equations of motion for individual particles is applied to an
ensemble of quasi-particles. The necessary expressions are constructed in terms
of a Hamilton function of a (quasi-)particle. A phonon contribution into
superfluid dynamic parameters is obtained from energy-momentum balance
equations for the phonon gas together with the conservation law for superfluids
as a whole. Relations between dynamic flows being in agreement with results of
relativistic hydrodynamic consideration are found. Based on the kinetic
approach a problem of relativistic variation of the speed of sound under phonon
influence at low temperature is solved.Comment: 23 pages, Revtex fil
A METHOD OF MOTION ANALYSIS FOR SELF-PROPELLED AQUATIC CRAFTS
Cimematography/videography has been the method of choice for the evaluation of self-propelled aquatic craft kinematics. However, direct measurements of acceleration of this type of craft has proved to be difficult. At Dalhousie the use of acceleration data in combination with video data has facilitated the analysis of rowing and canoeing kinematics. The aim of this study is to describe the method of motion analysis currently used at Dalhousie's Sport Science Lab. Description includes a custom software program developed to divide acceleration data into individual cycles and a cubic spline to normalize the data. In addition, impulse data was calculated integrating by acceleration data using Simpson's Rule as well as the Trapezoidal Rule. A multiple low pass 2nd order Butterworth digital filter has been used successfully to smooth the acceleration data. Video data has been used to confirm that the software correctly detects these variables
AN ANALYSIS OF SELECTED KINEMATIC VARIABLES IN SCULL ROWING USING MACON AND HATCHET OARS
The Hatchet oar is now used extensively in competitive rowing because it is believed to enhance performance. There has been little research to verify this. To determine possible differences between the scull kinematics using the Hatchet and Macon oar, a 24 year old male, lightweight rower, raced 2000 m on two separate days. An 8 mm video camera and a g.analyst accelerometer collected the data. A custom software program, divided the acceleration data into individual strokes and a cubic spline standardized the stroke length. Video data confirmed that the software correctly detected stroke cycles. The acceleration data was integrated using Simpson's Rule as well as the Trapezoidal Rule. First order derivatives where determined using first and second order finite differences and impulse. Velocity data was smoothed using a multiple low pass 2nd order Butterworth digital filter. Twelve discrete measures of percentage stroke length and the value at local vertices, as well as three measures of impulse where examined using one way ANOVAs. Most of the discrete measures examined were statistically significant (
Supersymmetric AdS5 black holes
The first examples of supersymmetric, asymptotically AdS5, black hole
solutions are presented. They form a 1-parameter family of solutions of minimal
five-dimensional gauged supergravity. Their angular momentum can never vanish.
The solutions are obtained by a systematic analysis of supersymmetric solutions
with Killing horizons. Other new examples of such solutions are obtained. These
include solutions for which the horizon is a homogeneous Nil or SL(2,R)
manifold.Comment: 31 pages. v2: References and calculation of holographic stress tensor
added. v3: Solutions preserve 2 supersymmetries. Our original claim that they
preserve 4 supersymmetries was based on Ref. [30], which contains a mistake
(the general timelike solution preserves 2, not 4, supersymmetries). Nothing
else affecte
Equation of state of cosmic strings with fermionic current-carriers
The relevant characteristic features, including energy per unit length and
tension, of a cosmic string carrying massless fermionic currents in the
framework of the Witten model in the neutral limit are derived through
quantization of the spinor fields along the string. The construction of a Fock
space is performed by means of a separation between longitudinal modes and the
so-called transverse zero energy solutions of the Dirac equation in the vortex.
As a result, quantization leads to a set of naturally defined state parameters
which are the number densities of particles and anti-particles trapped in the
cosmic string. It is seen that the usual one-parameter formalism for describing
the macroscopic dynamics of current-carrying vortices is not sufficient in the
case of fermionic carriers.Comment: 30 pages, 15 figures, uses ReVTeX, equation of state corrected,
comments and references added. Accepted for publication in Phys. Rev.
Fermionic massive modes along cosmic strings
The influence on cosmic string dynamics of fermionic massive bound states
propagating in the vortex, and getting their mass only from coupling to the
string forming Higgs field, is studied. Such massive fermionic currents are
numerically found to exist for a wide range of model parameters and seen to
modify drastically the usual string dynamics coming from the zero mode currents
alone. In particular, by means of a quantization procedure, a new equation of
state describing cosmic strings with any kind of fermionic current, massive or
massless, is derived and found to involve, at least, one state parameter per
trapped fermion species. This equation of state exhibits transitions from
subsonic to supersonic regimes while the massive modes are filled.Comment: 27 pages, 15 figures, uses ReVTeX. Shortened version, accepted for
publication in Phys. Rev.
Quicksort, Largest Bucket, and Min-Wise Hashing with Limited Independence
Randomized algorithms and data structures are often analyzed under the
assumption of access to a perfect source of randomness. The most fundamental
metric used to measure how "random" a hash function or a random number
generator is, is its independence: a sequence of random variables is said to be
-independent if every variable is uniform and every size subset is
independent. In this paper we consider three classic algorithms under limited
independence. We provide new bounds for randomized quicksort, min-wise hashing
and largest bucket size under limited independence. Our results can be
summarized as follows.
-Randomized quicksort. When pivot elements are computed using a
-independent hash function, Karloff and Raghavan, J.ACM'93 showed expected worst-case running time for a special version of quicksort.
We improve upon this, showing that the same running time is achieved with only
-independence.
-Min-wise hashing. For a set , consider the probability of a particular
element being mapped to the smallest hash value. It is known that
-independence implies the optimal probability . Broder et al.,
STOC'98 showed that -independence implies it is . We show
a matching lower bound as well as new tight bounds for - and -independent
hash functions.
-Largest bucket. We consider the case where balls are distributed to
buckets using a -independent hash function and analyze the largest bucket
size. Alon et. al, STOC'97 showed that there exists a -independent hash
function implying a bucket of size . We generalize the
bound, providing a -independent family of functions that imply size .Comment: Submitted to ICALP 201
Identification of a novel benzimidazole pyrazolone scaffold that inhibits KDM4 lysine demethylases and reduces proliferation of prostate cancer cells
Human lysine demethylase (KDM) enzymes (KDM1-7) constitute an emerging class of therapeutic targets, with activities that support growth and development of metastatic disease. By interacting with and co-activating the androgen receptor, the KDM4 subfamily (KDM4A-E) promotes aggressive phenotypes of prostate cancer (PCa). Knockdown of KDM4 expression or inhibition of KDM4 enzyme activity reduces the proliferation of PCa cell lines and highlights inhibition of lysine demethylation as a possible therapeutic method for PCa treatment. To address this possibility, we screened the ChemBioNet small molecule library for inhibitors of the human KDM4E isoform and identified several compounds with IC50 values in the low micromolar range. Two hits, validated as active by an orthogonal enzyme-linked immunosorbent assay, displayed moderate selectivity toward the KDM4 subfamily and exhibited antiproliferative effects in cellular models of PCa. These compounds were further characterized by their ability to maintain the transcriptionally silent histone H3 tri-methyl K9 epigenetic mark at subcytotoxic concentrations. Taken together, these efforts identify and validate a hydroxyquinoline scaffold and a novel benzimidazole pyrazolone scaffold as tractable for entry into hit-to-lead chemical optimization campaigns
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