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A New Cooperative Particle Swarm Optimizer with Landscape Estimation and Dimension PartitionWang, Ruei-yang 08 August 2010 (has links)
This thesis proposes a new hybrid particle swarm optimizer, which employs landscape estimation and the cooperative behavior of different particles to significantly improve the performance of the original algorithm. The landscape estimation is to explore the landscape of the function in order to predict whether the function is unimodal or multimodal. Then we can decide how to optimize the function accordingly. The cooperative behavior is achieved by using two swarms, in which one swarm explores only a single dimension at a time, and the other explores all dimensions simultaneously. Furthermore, we also propose a movement tracking-based strategy to adjust the maximal velocity of the particles. This strategy can control the exploration and exploitation abilities of the swarm efficiency. Finally, we testify the performance of the proposed approach on a suite of unimodal/multimodal benchmark functions and provide comparisons with other recent variants of the PSO. The results show that our approach outperforms other methods in most of the benchmark problems.
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An automatic optimization mechanism of circuit block partition for Fine-grain Multi-context Reconfigurable Process UnitChen, Jau-You 26 July 2006 (has links)
Due to the rapid development of today¡¦s multimedia communication systems, the complexity and scale of the systems increase day after day. For real-time computing of the systems which become more and more complicated, not only can we use VLSI chips, with the growth of manufacturing techniques of Integrated Circuit, we can apply the Reconfigurable Process Unit to improve real-time computing. Reconfigurable Process Unit is characterized by less cost in research and production as well as less time spent in research and development. Simultaneously, it processes more flexibility than VLSI chips and more suitability in taking advantageous position of real-time computing on an unspecified multimedia communication system. Fine-grain Multi-context Reconfigurable Process Unit has a mechanism of multi-context; therefore, it will take less time when the system reconfigures. This thesis deals with system environment of Computer-Aided Design under the structure of FMRPU, focusing on the placement and routing based on block partition method and designing an automatic optimization mechanism in accordance with historical records to elevate the rate of routable circuit.
With the spirit from various existing algorithm of circuit, we add the factors of block partition, which forms the implements of placement and routing based on block partition. Combined clustering and the limit caused by the hardware structure of FMRRPU, we can have an accurate block partition on FMRPU. Through the continual increase of historical records, the assessment for the upper limit of the argument of routable circuit will get closer to the actual figure. Simultaneously, after the Logic Block Partition, the probability of routable circuit will get great assurance, and the time consumed in lots of repetitious computing on un-routable circuit will decrease. The experimental result reveals that the modified placement cost function can obtain enormous improvement under the comparison with that mentioned the master thesis of Tzu-che Huang. Not only the routability steps up, the unnecessary consumption also reduces largely. In routing, the negotiated congestion-delay algorithm produced on the basis of the transformation of maze routing algorithm has great suitability in the operation on FMRPU, which has many optimization goals and limited routing resource. After the redefinition of the cost function and expenditure for routing, we can operate with accuracy and the time spent on the delayed circuit will decrease.
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Partition Timing Routing Protocol in Wireless Ad Hoc NetworksLin, Tsung-Hsien 07 July 2003 (has links)
Ad Hoc Networks are transmission networks on the structure of wireless networks by consisting of many mobile hosts. But it is no need to use any support by other communication infrastructures like Base Stations, and directly use wireless networks for data-transmission.
Because the feature of per host as fast movement, every host can join or go away as it likes, thus, the topology appeared from Ad Hoc networks will have higher probability to make packet loss or transmission delay and cause network flooded to do unnecessary re-send and lose the flow of running data.
We will explain generally some relative protocols of setting up routes and possible problems. Besides, describe relative researches of how to solve and reduce the possibility of problem happened.
Then, we will bring up a new constructive protocol (Partition-Timing Routing Protocol¡APTR), the protocol can adjust neighboring nodes of covered scope to select certain node to be own core node, if any covered node needs to transmit data to others outside the scope, it has to be managed by core node.
Besides, the timing for update and adjust data of per covered scope is different too and not as same as other ways which update timing is at the same time to reduce the load of the entirely network and more changeable.
Furthermore, it may increase the rate of update of per scope to get the target of succeeding data-transmission.
The simulation results will appear that the load and possibility of data transmission has more advantages than other ways.
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Structural and Biochemical Characterization of an Archaeal ParA ProteinLee, Jeehyun January 2015 (has links)
<p>DNA partition or segregation is the process that ensures the stable inheritance of genomic material. The majority of the bacterial plasmid and some chromosomal partition systems utilize ParA Walker-box-based partition systems. These systems require three components: a DNA centromere site, the ParA ATPase, and the ParB centromere binding protein. ParB binds to the centromere to form the partition complex, which then recruits the motor protein ParA. ParA mediates the partition of replicated DNA by a still poorly understood mechanism. Notably, recent data indicates that ParA Walker-box-based partition systems are employed not only by bacterial plasmids and chromosomes but also DNA elements in archaea. The work in this thesis focused on a homolog of the ParA protein from the first identified archaeal plasmid partition system, located on the plasmid pNOB8. pNOB8 plasmid is harbored in the thermophilic archaeaon, Sulfolobus solfataricus. The goals of this work were to structurally and biochemically characterize the ParA homolog to gain insights into its function.</p><p>Towards these goals, the structure of the ParA homolog was solved by X-ray crystallography in its apo and ADP bound states to resolutions of 2.45 Å and 2.73 Å, respectively. The overall structure was similar to bacterial ParA proteins. We next demonstrated that, similar to bacterial ParA proteins, this ParA homolog harbored ATP-dependent nonspecific DNA capabilities by using fluorescence polarization based DNA binding assays. By mutating the residues in the deviant Walker A motif, we were able to demonstrate the importance of ATP binding in its DNA binding function. Moreover, characterization of ATP and ADP binding were performed using ITC. Finally, we observed that ParA was able to form polymers in the presence of ATP, using negative stain electron microscopy. Our findings provide evidence that ParA Walker-box-based partition systems, which are the most common systems in bacteria, appear to also be found in archaea.</p> / Dissertation
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Gromov-Witten theory in dimensions two and threeGholampour, Amin 05 1900 (has links)
In this thesis, we solve for (equivariant) Gromov-Witten theories of some important classes of surfaces and threefolds, and study their relationships to other brances of mathematics.
The first object is the class of P2-bundles over a smooth curve C of genus g. Our bundles are of the form P(L0 + L1 +L2) for arbitrary line bundles L0, L1 and L2 over C. We compute the partition functions of these invariants for all classes of the form s + nf, where s is a section, f is a fiber and n is an integer. In the case where the class is Calabi-Yau, i.e., K • (s + nf) = 0,the partition function is given by
3g (2sin u/2) 2g-2
As an application, one can obtain a series of full predictions for the equivariant Donaldson Thomas invariants for this family of non-toric threefolds.
Secondly, we compute the C-equivariant quantum cohomology ring of Y, the minimal resolution of the DuVal singularity C2 /G where G is a finite subgroup of SU(2). The quantum product is expressed in terms of an ADE root system canonically associated to G. We generalize the resulting Frobenius manifold to non-simply laced root systems to obtain an n parameter family of algebra structures on the affine root lattice of any root system. Using the Crepant Resolution Conjecture, we obtain a prediction for the orbifold Grornov-Witten potential of [C2 /G].
Thirdly, for a polyhedral group G, that is a finite subgroup of S0(3), we completely determine the Gromov-Witten theory of Nakamura's G- Hilbert scheme, which is a preferred Calabi-Yau resolution of the polyhedral singularity C3/G. The classical McKay correspondence determines the (classical) cohomology of this resolution in terms of the representation theory of G. We express the Cromov-Witten potential in terms of an ADE root system associated to G. As an application, we use the Crepant Resolution Conjecture to provide a full prediction for the orbifold Grornov-Witten invariants of [C3/G].
Finally, in the case that G is the group A4 or Z2 x Z2, we compute the integral of Ag on the Hurwitz locus HG C Mg of curves admitting a degree 4 cover of P1 having monodromy group G. We compute the generating functions for these integrals and write them as a trigonometric expression summed over the positive roots of the E6 and D4 root systems respectively. As an application, we prove the Crepaut Resolution Conjecture for the orbifolds [C3/A4] and [C3/(Z2 x Z2)].
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Asymptotic Distributions for Block Statistics on Non-crossing PartitionsLi, Boyu January 2014 (has links)
The set of non-crossing partitions was first studied by Kreweras in 1972 and was known to play an important role in combinatorics, geometric group theory, and free probability. In particular, it has a natural embedding into the symmetric group, and there is an extensive literature on the asymptotic cycle structures of random permutations. This motivates our study on analogous results regarding the asymptotic block structure of random non-crossing partitions.
We first investigate an analogous result of the asymptotic distribution for the total number of cycles of random permutations due to Goncharov in 1940's: Goncharov showed that the total number of cycles in a random permutation is asymptotically normally distributed with mean log(n) and variance log(n). As a analog of this result, we show that the total number of blocks in a random non-crossing partition is asymptotically normally distributed with mean n/2 and variance n/8.
We also investigate the outer blocks, which arise naturally from non-crossing partitions and has many connections in combinatorics and free probability. It is a surprising result that among many blocks of non-crossing partitions, the expected number of outer blocks is asymptotically 3. We further computed the asymptotic distribution for the total number of blocks, which is a shifted negative binomial distribution.
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Gromov-Witten theory in dimensions two and threeGholampour, Amin 05 1900 (has links)
In this thesis, we solve for (equivariant) Gromov-Witten theories of some important classes of surfaces and threefolds, and study their relationships to other brances of mathematics.
The first object is the class of P2-bundles over a smooth curve C of genus g. Our bundles are of the form P(L0 + L1 +L2) for arbitrary line bundles L0, L1 and L2 over C. We compute the partition functions of these invariants for all classes of the form s + nf, where s is a section, f is a fiber and n is an integer. In the case where the class is Calabi-Yau, i.e., K • (s + nf) = 0,the partition function is given by
3g (2sin u/2) 2g-2
As an application, one can obtain a series of full predictions for the equivariant Donaldson Thomas invariants for this family of non-toric threefolds.
Secondly, we compute the C-equivariant quantum cohomology ring of Y, the minimal resolution of the DuVal singularity C2 /G where G is a finite subgroup of SU(2). The quantum product is expressed in terms of an ADE root system canonically associated to G. We generalize the resulting Frobenius manifold to non-simply laced root systems to obtain an n parameter family of algebra structures on the affine root lattice of any root system. Using the Crepant Resolution Conjecture, we obtain a prediction for the orbifold Grornov-Witten potential of [C2 /G].
Thirdly, for a polyhedral group G, that is a finite subgroup of S0(3), we completely determine the Gromov-Witten theory of Nakamura's G- Hilbert scheme, which is a preferred Calabi-Yau resolution of the polyhedral singularity C3/G. The classical McKay correspondence determines the (classical) cohomology of this resolution in terms of the representation theory of G. We express the Cromov-Witten potential in terms of an ADE root system associated to G. As an application, we use the Crepant Resolution Conjecture to provide a full prediction for the orbifold Grornov-Witten invariants of [C3/G].
Finally, in the case that G is the group A4 or Z2 x Z2, we compute the integral of Ag on the Hurwitz locus HG C Mg of curves admitting a degree 4 cover of P1 having monodromy group G. We compute the generating functions for these integrals and write them as a trigonometric expression summed over the positive roots of the E6 and D4 root systems respectively. As an application, we prove the Crepaut Resolution Conjecture for the orbifolds [C3/A4] and [C3/(Z2 x Z2)]. / Science, Faculty of / Mathematics, Department of / Graduate
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Multiple Independent Extrusion Heads for Fused Deposition ModelingWachsmuth, John Paul 26 March 2008 (has links)
Fused Deposition Modeling is a rapid prototyping technique in which miniature extruders melt filaments of polymeric materials. The extruder is mounted to an X/Y stage, and a computer controls the machine so that the polymer is deposited in only the appropriate locations. Material is deposited on one layer at a time so that the desired shape is built from the bottom up. While Fused Deposition Modeling has many advantages, it is poorly suited for large parts or for parts with thick walls due to the amount of time that is required to fabricate them. One strategy to reduce the build time is to implement multiple independent extrusion-heads. This thesis addresses various issues and concerns that arise while designing a multiple independent extrusion-head Fused Deposition Modeling system. The greatest design challenges and most critical issues are identified, and then solutions are presented. Physical samples and experiments verify feasibility when possible. Suitable material deposition strategies have been formulated to allow multiple independent extrusion heads to work simultaneously to reduce build time while allowing for a larger build envelope. These strategies produce parts that have nearly identical mechanical properties as those made on a single-head machine. This work seeks to provide information that is useful for designing a multiple independent extrusion-head Fused Deposition Modeling, regardless the number of extrusion heads or machine configuration. Implementing multiple independent extrusion heads will greatly reduce the fabrication time while allowing for a larger build envelope. / Master of Science
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The prediction of blood–tissue partitions, water–skin partitions and skin permeation for agrochemicalsAbraham, M.H., Gola, J.M.R., Ibrahim, A., Acree, W.E. Jr., Liu, Xiangli 13 October 2013 (has links)
Yes / BACKGROUND: There is considerable interest in the blood–tissue distribution of agrochemicals, and a number of researchershave developed experimental methods for in vitro distribution. These methods involve the determination of saline–blood andsaline–tissue partitions; not only are they indirect, but they do not yield the required in vivo distribution.RESULTS: The authors set out equations for gas–tissue and blood–tissue distribution, for partition from water into skin andfor permeation from water through human skin. Together with Abraham descriptors for the agrochemicals, these equationscan be used to predict values for all of these processes. The present predictions compare favourably with experimental in vivoblood–tissue distribution where available. The predictions require no more than simple arithmetic.CONCLUSIONS: The present method represents a much easier and much more economic way of estimating blood–tissuepartitions than the method that uses saline–blood and saline–tissue partitions. It has the added advantages of yielding therequired in vivo partitions and being easily extended to the prediction of partition of agrochemicals from water into skin andpermeation from water through skin.
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Prestandatest för olika sektioner av hårddiskarFranzén, Jesper, Svensson, Mikael, Åberg, Andreas January 2010 (has links)
<p>Syftet med detta arbete var att genom prestandatester undersöka den förbättring i läs- och skrivhastighet samt medelaccesstid som kan uppnås då data placeras på de yttre sektionerna av hårddiskens skivor, jämfört med om data placeras över hela hårddiskskivornas yta. En hårddisk har högre överföringshastighet i den yttersta sektionen av hårddisken och lägre överföringshastighet i den innersta sektionen. Arbetet analyserade den påverkan på prestanda som ovan nämnda dataplacering har på en enskild hårddisk och olika RAID-konfigurationer. Rapporten är intressant då det är lättare att med informationen som presenteras i rapporten, planera hårddiskkonfigurationer som leder till optimerad prestanda. En experimentell metod användes för att utreda prestandaskillnaderna. Prestandatesterna utfördes i programmet HD Tune Pro, vilket har en short stroke-funktion som gör det möjligt att begränsa testerna till endast en del i början av hårddiskens lagringsutrymme. Prestandatesterna utfördes tre gånger vardera för att få ett mer trovärdigt resultat. En märkbar prestandaförbättring blev resultatet av testerna av hårddiskkonfigurationerna då short stroke-funktionen var aktiverad, i jämförelse med då short stroke inte var aktiverat. En praktisk tillämpning av lagring på de yttre sektionerna av hårddiskskivorna, är att skapa en partition som tar upp en del av hårddiskskivornas yttre lagringsyta. Denna tillämpning rekommenderas för personer med hemdatorer som vill uppnå optimerad hårddiskprestanda genom planering av partitionering. Företag som använder RAID-konfigurationer, bör också ha planering av partitionering i åtanke. Ett förslag till vidare behandling av området är att genomföra prestandatester, vars resultat jämförs med prestandavärden för hårddiskar som är konstruerade för hög prestanda.</p><p> <strong>Nyckelord</strong>: hårddisk, partition, prestanda, RAID, sektioner, short stroke</p>
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