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A biomedical engineering approach to investigating flow and wall shear stress in contracting lymphatics
Collecting microlymphatics play a vital role in promoting lymph flow from the initial lymphatics in the interstitial spaces to the large transport lymph ducts. In most tissues, the primary mechanism for producing this flow is the spontaneous contractions of the lymphatic wall. Individual units, known as lymphangion, are separated by valves that help prevent backflow when the vessel contracts, thus promoting flow through the lymphatic network. Lymphatic contractile activity is inhibited by flow in isolated lymphatics, however there are virtually no in situ measurements of lymph flow in these vessels. Initially, a high speed imaging system was set up to image in situ preparations at 500...
The mechanical behavior of saturated soil is mainly governed by the interaction between the soil skeleton and the pore fluid, and this interaction may lead to significant loss of strength known as liquefaction under seismic loadings. The main objective of this thesis is to develop and implement a cyclic constitutive model capable of modeling soil skeleton dilatancy during earthquake excitation. The constitutive model is based on the fuzzy-set plasticity theory and enhancement is made on the description of dilatancy behavior under cyclic loading. A robust Biot formulation, in which the governing equations of motion of the soil mixture are coupled with the global mass balance equations,...
A chemical genomic approach towards determining the molecular target of anti-proliferative compounds
Drug target identification is a time consuming stage of the drug discovery process. Chemical genomics offers a solution to this hurdle. In chemical genomics, a target specific chemical ligand is applied on a genomic scale. This technique was used to identify the molecular target of anti-proliferative agents using changes in mRNA transcript levels upon treatment. Whole-genome transcription profiling experiments employed the eukaryotic model organism Saccharomyces cerevisiae for small-molecule perturbation experiments in addition to traditional genetics. Chemical genomics was used to examine the molecular target of borrelidin, a macrolide with conflicting published biological activitie...
A composite semantic communications framework for representation of agent communication language semantics
From the variety of agent communication languages that have been proposed since the early 1990's, it can be seen that there is no general agreement on what constitutes a necessary core of semantics for agent communication languages. This has led some researchers to observe that agent communication languages have been implemented ad hoc. This dissertation develops and evaluates an approach towards representing the semantics of agent communication languages explicitly in the notation of conceptual graphs. The speech act theories of Austin, Searle and Habermas that are cited as having motivated the semantics of some agent communication languages are also represented in conceptual graph n...
There is an imbalance between personal and algorithmic control in existing techniques for element-based computer graphics. A reframing of the traditional graphics pipeline is used to address this. By turning modelling and rendering into an interactive process, and introducing semi-autonomous agents to manage elements, we develop a framework through which it is possible to build applications with a given control balance. Agents negotiate control of their representations on a canvas via interactions in agent space. Interaction with the rendered image on canvas is conveyed to agents responsible for that image, which interpret the interaction and adjust the underlying model appropriately....
A laminar cortical model of three-dimensional surface perception and figure-ground separation: Stereogram depth, lightness, and amodal completion
In viewing a 3D scene, object features are seen on 3D surfaces infused with lightness and color at correct depths. By only focusing on how left and right features are correctly matched, most 3D vision models have not explained how this happens. A 3D LAMINART model (Grossberg and Howe, 2003; Cao and Grossberg, 2005) proposed that laminar cortical mechanisms interact to create 3D surface percepts using interactions between boundary and surface representations. Previous work using this model explained perception of relatively simple objects, like bars and blocks, in relatively simple spatial configurations that did not contain any mutual occlusions. This thesis extends the 3D LAMINART mo...
Forensic analysis is the process of understanding, re-creating, and analyzing arbitrary events that have previously occurred. It seeks to answer such questions as how an intrusion occurred, what an attacker did during an intrusion, and what the effects of an attack were. Currently the field of computer forensics is largely ad hoc. Data is generally collected because applications log it for debugging purposes or because someone thought it to be important. Practical forensic analysis has traditionally traded off analyzability against the amount of data recorded. Recording less data puts a smaller burden both on computer systems and on the humans that analyze them. Not recording enough ...
A modified ring shear test device for determining the hydro-mechanical behaviour of unsaturated soils
This thesis presents the design details of an automated modified ring shear apparatus for the testing of unsaturated soils using the axis translation technique. The system is fully automated and it can be used for conducting Constant Load and constant Suction (CLS) shear tests, Constant Volume and constant Suction (CVS) shear tests, Constant Load and constant Water content (CLW) shear tests as well as Constant Volume and constant Water content (CVW) shear tests. In addition to shear tests, the soil-water retention curve (SWRC) can also be generated for the same specimen in the same testing device. The principal advantages of the device include its ability to shear unsaturated soils to...
Competitive international business environment in the global textile and apparel market has forced many textile and apparel firms to concentrate on supply chain management in order to face with fierce competition. Supplier selection process, a part in supply chain, has been a prime concern recently because many of firms in the world in general and in Vietnam in particular have been spending considerable amount on sourcing. Although the selection of suppliers is important, most of Vietnamese textile and apparel companies have a very simple process and only choose suppliers intuitively. This is one of the reasons causing high sourcing costs that often result high-price output, unstable ...
Security is a serious concern in wireless networks. In order to eliminate the vulnerabilities in previous Standards, the IEEE 802.11i Standard is designed to provide security enhancements in MAC layer. The authentication process consists of several components, including an 802.1X authentication phase using TLS over EAP, a 4-Way Handshake to establish a fresh session key, and an optional Group Key Handshake for group communications. The objective of this work is to analyze IEEE 802.11i with respect to data confidentiality, integrity, mutual authentication, and availability. Under our threat model, 802.111 appears to provide effective data confidentiality and integrity when CCMP is use...
We introduce the notion of super vertex operator algebra with enhanced conformal structure, which is a refinement of the notion of super vertex operator algebra, and we present applications of this notion to three sporadic simple groups: the largest sporadic group of Conway, the sporadic group of Suzuki, and the sporadic group of Rudvalis. For the Conway group we construct what may be considered a natural super-analogue of the Moonshine Module, where the role of the Virasoro algebra is now played by the N = 1 Virasoro superalgebra, and we find that the full group of automorphisms is Conway's largest sporadic group. We also verify a uniqueness result for this object, which is directly...
Multiple drug resistance is quickly becoming an obstacle to the treatment of disease. Bacteria, parasitic protazoa, yeast and mammalian cancer cells develop mutations that render them resistant to a wide variety of structurally and chemically different compounds. In the yeast Saccharomyces cerevisiae, one of the main mechanisms causing drug resistance is the loss of function of ABC transporters that are responsible for effluxing the drug from the cell. The main ABC transporter responsible for efflux of many different drugs is Pdr5p. However, earlier work (Fleckenstein et.al. 1999; Shallom and Golin, 1996) shows that this is not the only pathway mediating resistance to these drugs. Th...
A new method to solve stochastic programming problems under probabilistic constraint with discrete random variables
In this dissertation, probabilistic constrained stochastic programming problems are con¬sidered with discrete random variables on the r.h.s. in the stochastic constraints. In Chapter 2 and 3, it is assumed that the random vector has multivariate Poisson, bino¬mial or geometric distribution. We prove a general theorem that implies that in each of the above cases the c.d.f. majorizes the product of the univariate marginal c.d.f's and then use the latter one in the probabilistic constraints. The new problem is solved in two steps: (1) first we replace the c.d.f's in the probabilistic constraint by smooth logconcave functions and solve the continuous problem; (2) search for the optimal so...
A one-dimensional model of blood flow in arteries with friction, convection and unsteady Taylor diffusion based on the Womersley velocity profile
In this thesis, we present a one-dimensional model for blood flow in arteries, without assuming an a priori shape for the velocity profile across an artery. We combine the one-dimensional equations for conservation of mass and momentum with the Womersley model for the velocity profile in an iterative way. The pressure gradient of the one-dimensional model drives the Womersley equations, and the velocity profiles calculated then feed back into both the friction and nonlinear parts of the one-dimensional model. Besides enabling us to evaluate the friction correctly and also use the velocity profile to correct the nonlinear terms, the velocity profiles play a central role in the calculat...
Many types of auctions are discussed in the literature such as single item auctions, sequential auctions, and combinatorial auctions. Proxy bidding has proven useful in solving iterative auction problems in many real-world auction formats. In this dissertation, I propose a new type of iterative auction called the Simple Combinatorial Proxy Auction. A popular method for solving the iterative proxy auction problems is simulating the incremental bidding decisions of the agents. However, this approach has some disadvantages. In this dissertation, I present a new approach called the Price Trajectory Algorithm to solve iterative auction problems. This approach computes the agents’ allocati...
A proposal for Vietnam to improve its intellectual property laws from the case Elsevior complaints Sci Hub for copyright infringement
The dispute between Elsevior and Sci Hub clearly raises the fundamental conﬂict about the reasons we have IPR law, here copyrights, in the frst place. Here the conﬂict is between the value of encouraging innovation by the grant of copyright protection to Elsevier and the value of broad access to information, especially by those who may otherwise not have access due to the limitations imposed by the owner of the copyright (in this case, Elsevier’s licensing arrangements, or “paywalls”). Because of its extra-jurisdictional aspects it also raises simple questions of domestic server repositories respecting the copyrights and avoiding further conﬂicts by shutting down access to the contest...
A study on backfire control and performance improvement by changing the valve timings in a hydrogen-fueled engine with external injection
Hydrogen-fueled engines with external mixture formation have potentially high thermal efficiency because of a more homogeneous inlet mixture. In addition, the structure of such engines is relatively simple. The practical use of hydrogen can be visible in the short term. The occurrence of backfire at high engine load conditions, however, is an important problem. Because of this, the method of attaining both high efficiency and high power without backfire in a hydrogen-fueled engine is the most important key. The backfire phenomena of hydrogen-air mixtures in the intake system are often a result of backflow of a pre-ignited fast flame from combustion chamber during the valve overlap pe...