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Hand Gesture Detection & Recognition SystemKhan, Muhammad January 2012 (has links)
The project introduces an application using computer vision for Hand gesture recognition. A camera records a live video stream, from which a snapshot is taken with the help of interface. The system is trained for each type of count hand gestures (one, two, three, four, and five) at least once. After that a test gesture is given to it and the system tries to recognize it.A research was carried out on a number of algorithms that could best differentiate a hand gesture. It was found that the diagonal sum algorithm gave the highest accuracy rate. In the preprocessing phase, a self-developed algorithm removes the background of each training gesture. After that the image is converted into a binary image and the sums of all diagonal elements of the picture are taken. This sum helps us in differentiating and classifying different hand gestures.Previous systems have used data gloves or markers for input in the system. I have no such constraints for using the system. The user can give hand gestures in view of the camera naturally. A completely robust hand gesture recognition system is still under heavy research and development; the implemented system serves as an extendible foundation for future work.
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PRECISION MEASUREMENTS OF DEUTERON PHOTODISINTEGRATION USING LINEARLY POLARIZED PHOTONS OF 14 AND 16 MEVBlackston, Matthew Allen 27 July 2007 (has links)
A precision measurement of the d(gamma
,n)p reaction was performed at the High
Intensity
gamma-ray Source (HIGS), which is located at the Duke Free Electron Laser
Laboratory on the campus of Duke University. The
gamma-ray beams were nearly 100%
linearly polarized, allowing the angular distributions of both the analyzing power
and unpolarized cross section to be measured at 14 and 16 MeV. The photons were
incident on a heavy water target and the neutrons from the photodisintegration
reaction were detected using the Blowfish detector array, which consists of 88 liquid
scintillator detectors with large angular coverage.A transition matrix element (TME) analysis was performed on the data which
allowed the amplitudes of the TMEs which contribute to the reaction at these energies
to be extracted. This was done by invoking Watson's theorem, which fixes the relative
TME phases using the n-p scattering phase shifts, leaving the TME amplitudes as
free parameters in fits to the data. The results indicated very good agreement with
a recent potential model calculation for the amplitudes of the three electric dipole
(E1) p-waves, which account for over 90% of the cross section at these energies.The extracted TME amplitudes were then used to construct the observable which
enters into the Gerasimov-Drell-Hearn (GDH) Sum Rule integrand. The results are
the first experimental indication of a positive value of the GDH integrand in the
region near photodisintegration threshold. A positive value at these energies has
been shown by theory to be due to relativistic contributions. / Dissertation
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Circuit Design of LDPC Decoder for IEEE 802.16e systemsWang, Jhih-hao 29 March 2010 (has links)
A circuit design of Low Density Parity Check (LDPC) decoder for IEEE 802.16e systems is with new overlapped method is proposed in this thesis. This circuit can be operated with 19 modes which are corresponding to block sizes of 576, ¡K, 2304. LDPC decoders can be implemented by using iterations with Variable Node and Check Node Processes. The hardware utilization ratio, which can be enhanced from 50% to 100% by using our proposed overlapped method, is better than traditional overlapped method. In [2], the traditional overlapped method utilization ratio just can be enhanced from 50% to 75% for IEEE 802.16e LDPC decoder with code rate 1/2. Under the same operating frequency, our proposed method can further increase 25% when compared with traditional overlapped method [2]. In this thesis, we also propose two circuit architectures to increase the operating frequency. First, we use a faster comparison circuit in our comparison unit [1]. Second, we use Carry Save Adder¡]CSA¡^method [8] to replace the common adder unit.
The circuit is carried out by TSMC CMOS 0.18£gm 1P6M process with chip area 3.11 x 3.08 mm2. In the gate level simulation, the output data rate of this circuit is above 78.4MHz, so the circuit can meet the requirement of IEEE 802.16e system.
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Exact Methods In Fractional Combinatorial OptimizationUrsulenko, Oleksii 2009 December 1900 (has links)
This dissertation considers a subclass of sum-of-ratios fractional combinatorial optimization
problems (FCOPs) whose linear versions admit polynomial-time exact algorithms.
This topic lies in the intersection of two scarcely researched areas of fractional
programming (FP): sum-of-ratios FP and combinatorial FP. Although not extensively
researched, the sum-of-ratios problems have a number of important practical applications
in manufacturing, administration, transportation, data mining, etc.
Since even in such a restricted research domain the problems are numerous,
the main focus of this dissertation is a mathematical programming study of the
three, probably, most classical FCOPs: Minimum Multiple Ratio Spanning Tree
(MMRST), Minimum Multiple Ratio Path (MMRP) and Minimum Multiple Ratio
Cycle (MMRC). The first two problems are studied in detail, while for the other one
only the theoretical complexity issues are addressed.
The dissertation emphasizes developing solution methodologies for the considered
family of fractional programs. The main contributions include: (i) worst-case
complexity results for the MMRP and MMRC problems; (ii) mixed 0-1 formulations
for the MMRST and MMRC problems; (iii) a global optimization approach for the
MMRST problem that extends an existing method for the special case of the sum of
two ratios; (iv) new polynomially computable bounds on the optimal objective value
of the considered class of FCOPs, as well as the feasible region reduction techniques based on these bounds; (v) an efficient heuristic approach; and, (vi) a generic global
optimization approach for the considered class of FCOPs.
Finally, extensive computational experiments are carried out to benchmark performance
of the suggested solution techniques. The results confirm that the suggested
global optimization algorithms generally outperform the conventional mixed 0{1 programming
technique on larger problem instances. The developed heuristic approach
shows the best run time, and delivers near-optimal solutions in most cases.
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Strong Decays Of The Dsj (2317) Mesons Using Qcd Sum RulesAydemir, Ufuk 01 August 2007 (has links) (PDF)
Unexpected properties of recently discovered mesons DsJ(2317) and DsJ(2460) have caused an excitement in the high energy community. These mesons are under experimental study in BaBar, Belle and CLEO. The experimental data on
these mesons is quite limited at the moment, but it is expected to be improved in the following years. The unexpected properties of these mesons, such as the low
mass, and small width, have caused speculations about their structure. Various models have been proposed which go beyond the simple quark-antiquark picture of the mesons, such as a meson molecule, or a four-quark state. Therefore,
understanding the underlying structure of these mesons can reveal a deeper understanding of QCD. In this thesis, the strong decay of the DsJ(2317) meson, DsJ(2317)--> / Dspi0, is studied using three-point QCD Sum Rules method in the
conventional cs framework. DsJ(2317) -> / Dspi0 decay violates isospin symmetry. Therefore, this decay is studied as a two stage process / an isospin conserving DsJ(2317) --> / Ds eta decay followed by the conversion of eta into a pi0 due to isospin violation.
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Study Of Dsj(2317) And Dsj(2460) Meson Properties Within The Quark Model And Qcd Sum RulesTandogan, Asli 01 August 2007 (has links) (PDF)
The recently discovered DsJ(2317) and DsJ(2460) mesons had stimulated many theoretical and experimental studies due to their unexpected properties. In this thesis, we make a review of the predictions on the properties of these mesons
using the quark model and QCD Sum Rules. We studied different models about the structure of these mesons, which are suggested because of their unexpected properties. Moreover, using the quark model which implies that the structure of DsJ meson as cs and QCD Sum Rules method, we investigated the semileptonic decay DsJ(2317)--> / D0 l nu.
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Investigating The Semileptonic B To K_1(1270,1400) Decays In Qcd Sum RulesDag, Huseyin 01 February 2010 (has links) (PDF)
Quantum Chromodynamics(QCD) is part of the Standard Model(SM) that describes the interaction of fundamental particles. In QCD, due to the fact that strong coupling constant is large at low energies, perturbative approaches do not work. For this reason, non-perturbative approaches have to be used for studying the properties of hadrons. Among several non-perturbative approaches, QCD sum rules is one of the reliable methods which is applied to understand the properties of hadrons and their interactions.
In this thesis, the semileptonic rare decays of $B$ meson to $K_{1}(1270)$ and $K_{1} (1400)$ are analyzed in the framework of three point QCD sum rules approach. The $Brightarrow K_{1} (1270,1400) ell^+ ell^-$ decays are significant flavor changing neutral current (FCNC) decays of the $B$ meson, since FCNC processes are forbidden at tree level at SM. These decays are sensitive to the new physics beyond SM. The radiative $Brightarrow K_{1}(1270) gamma$ decay is observed experimentally. Although semileptonic $Bto K_1(1270,1400)$ decays are still not observed, they are expected to be observed at future B factories. These decays happens at the quark level with $brightarrow s ell^+ ell^- $ transition, providing new opportunities for calculating CKM matrix elements: $V_{tb}$ and $V_{ts}$.
Applying three point QCD sum rules to $Brightarrow K_{1} (1270,1400) ell^+ ell^-$ decays is tricky, due to the fact that the $K_{1} (1270)$ and $K_{1} (1400)$ states are the mixtures of ideal $^{3}P_{1}(K_{1}^{A})$ and $^{1}P_{1}(K_{1}^{B})$ orbital angular momentum states. First, by taking axial vector and tensor current definitions for $K_1$ mesons, the transition form factors of $Brightarrow K_{1A} ell^+ ell^-$ and $Brightarrow K_{1B} ell^+ ell^-$ are calculated. Then using the definitions for $K_1$ mixing, the transition form factors of $Brightarrow K_{1} (1270,1400) ell^+ ell^-$ decays are obtained. The results of these form factors are used to estimate the branching ratio of $B$ meson into $K_1(1270)$ and $K_1(1400)$. The results obtained for form factors and branching fractions are also compared with the ones in the literature.
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The structure of langmuir monolayers probed with vibrational sum frequency spectroscopyGurau, Marc Cory 29 August 2005 (has links)
Langmuir monolayers can be employed as simple model systems to study interactions at surfaces. Such investigations are important to fields ranging from biology to materials science. Herein, several aspects of these films and their associated water structure have been examined with vibrational sum frequency spectroscopy (VSFS). This second order nonlinear optical spectroscopy is particularly well suited for simultaneous investigations of the monolayer and the associated water structure with unprecedented surface specificity. The structures of these systems were altered through the control of experimental parameters including monolayer pressure, subphase temperature, pH and ionic content. Thermodynamic information about structural changes in a fatty amine monolayer's hydrophobic region was obtained by observation of the pressure and temperature dependence of the monolayer's solid to liquid phase transition. Further studies used the coordination of divalent cations to acid monolayers to perturb the water layers nearest to the film which enabled a better understanding of the water related VSFS features from these hydrophilic interfaces. Information from both the monolayer and water structure was then combined in order to examine the role of water in mediating ion-biomaterial interactions, often expressed in terms of the Hofmeister series.
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Semiclassical and path-sum Monte Carlo analysis of electron device physicsDavid, John Kuck 01 February 2012 (has links)
The physics of electron devices is investigated within the framework of
Semiclassical Monte Carlo and Path-Sum Monte Carlo analysis. Analyses of shortchannel
III-V trigate nanowire and planar graphene FETs using a Semiclassical Monte
Carlo algorithm are provided. In the case of the nanowire FETs, the bandstructure and
scattering effects of a survey of materials on the drain current and carrier concentration
are investigated in comparison with Si FETs of the same geometry. It is shown that for
short channels, the drain current is predominantly determined by associated change in
carrier velocity, as opposed to changes in the carrier concentration within the channel.
For the graphene FETs, we demonstrate the effects of Zener tunneling and remote
charged impurities on the device performance. It is shown that, commensurate with
experimental evidence, the devices have great difficulty turning off as a result of the
Zener tunneling, and have a conductivity minimum which is affected by remote
impurities inducing charge puddling. Each material modeled is matched with
experimental data by calibrating the scattering rates with velocity-field curves. Material
and geometry specific parameters, models, and methods are described, while discussion
of the basic semiclassical Monte Carlo method is left to the extensive volume of
publications on the subject. Finally, a novel quantum Path-Sum Monte Carlo algorithm is described and applied to a test case of two layered 6 atom rings (to mimic graphene), to
demonstrate the effectiveness of the algorithm in reproducing phase transitions in
collective phenomena critical to possible beyond-CMOS devices. First, the method and
its implementation are detailed showing its advantages over conventional Path Integral
Monte Carlo and other Quantum Monte Carlo approaches. An exact solution of the
system within the framework of the algorithm is provided. A Fixed Node derivative of
the Path Sum Monte Carlo method is described as a work-around of the infamous
Fermion sign problem. Finally, the Fixed Node Path-Sum Monte Carlo algorithm is
implemented to a set of points showing the accuracy of the method and the ability to give
upper and lower bounds to the phase transition points. / text
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Polynomial quandle cocycles, their knot invariants and applicationsAmeur, Kheira 01 June 2006 (has links)
A quandle is a set with a binary operation that satisfies three axioms that corresponds to the three Reidemeister moves on knot diagrams. Homology and cohomology theories of quandles were introduced in 1999 by Carter, Jelsovsky,Kamada, Langford, and Saito as a modification of the rack (co)homology theory defined by Fenn, Rourke, and Sanderson. Cocycles of the quandle (co)homology, along with quandle colorings of knot diagrams, were used to define a new invariant called the quandle cocycle invariants, defined in a state-sum form. This invariant is constructed using a finite quandle and a cocyle, and it has the advantage that it can distinguish some knots from their mirror images, and orientations of knotted surfaces. To compute the quandle cocycle invariant for a specific knot, we need to find a quandle that colors the given knot non-trivially, and find a cocycle of the quandle.
It is not easy to find cocycles,since the cocycle conditions form a large, over-determined system of linear equations. At first the computations relied on cocycles found by computer calculations. We have seen significant progress in computations after Mochizuki discovered a family of 2- and 3-cocycles for dihedral and other linear Alexander quandles written by polynomial expressions. In this dissertation, following the method of the construction by Mochizuki, a variety of n-cocycles for n >̲ 2 are constructed for some Alexander quandles, given by polynomial expressions. As an application, these cocycles are used to compute the invariants for (2,n)-torus knots, twist knots and their r-twist spins. The calculations in the case of (2,n)-torus knots resulted in formulas that involved the derivative of the Alexander polynomial. Non-triviality of some quandle homology groups is also proved using these cocycles. Another application is given for tangle embeddings.
The quandle cocycle invariants are used as obstructions to embedding tangles in links. The formulas for the cocycle invariants of tangles are obtained using polynomial cocycles, and by comparing the invariant values, information is obtained on which tangles do not embed in which knots. Tangles and knots in the tables are examined, and concrete examples are listed.
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