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Adaptive Scalable Protocols For Heterogeneous Wireless Networks, Vamsi Krishna Paruchuri
Adaptive Scalable Protocols For Heterogeneous Wireless Networks, Vamsi Krishna Paruchuri
LSU Doctoral Dissertations
The focus of this dissertation is to propose analytical models to study the impact of collisions and interference in heterogeneous wireless networks and propose simple scalable and lightweight protocols that use these models to adapt to network conditions thus increasing efficiency, decreasing energy consumption and prolonging network lifetime. The contributions of this dissertation are multifold and are summarized as follows: - Analytical models to study the impact of collisions and interference on both broadcast and unicast messages. These analytical models are incorporated into the proposed protocols to adapt to the prevailing network conditions to improve their performance. - Optimized Flooding …
Nutrient Constraints On Plant Community Production And Organic Matter Accumulation Of Subtropical Floating Marshes, Guerry O., Jr. Holm Jr.
Nutrient Constraints On Plant Community Production And Organic Matter Accumulation Of Subtropical Floating Marshes, Guerry O., Jr. Holm Jr.
LSU Doctoral Dissertations
In the cycle of delta growth and decay, peat-forming wetlands span a time and space continuum. Later in the delta cycle, freshwater floating marshes become increasingly removed from external sediment subsidy and internal nutrient cycling controls plant productivity and organic matter accumulation. An interesting question is whether increased external nutrient loading can affect the basic processes that lead to peat formation—plant production and organic matter decomposition. I conducted several field studies to understand whether belowground organic matter accumulation and decomposition were affected with increased nutrient exposure; in addition, the plant community was monitored over three years. A laboratory soil respiration …
Population Boundaries And Gravitational-Wave Templates For Evolving White Dwarf Binaries, Ravi Kumar Kopparapu
Population Boundaries And Gravitational-Wave Templates For Evolving White Dwarf Binaries, Ravi Kumar Kopparapu
LSU Doctoral Dissertations
We present results from our analysis of double white dwarf (DWD) binary star systems in the inspiraling and mass-transfer stages of their evolution. Theoretical constraints on the properties of the white dwarf stars allow us to map out the DWD trajectories in the gravitational-wave amplitude-frequency domain and to identify population boundaries that define distinct sub-domains where inspiraling and/or mass-transferring systems will and will not be found. We identify for what subset of these populations it should be possible to measure frequency changes and, hence, directly follow orbit evolutions given the anticipated operational time of the proposed space-based gravitational-wave detector, LISA. …
Fabrication, Characterization And Properties Of Hiercchically Ordered Nanocomposites, Avinash Dundigalla
Fabrication, Characterization And Properties Of Hiercchically Ordered Nanocomposites, Avinash Dundigalla
LSU Doctoral Dissertations
The objectives of this research are to study the structure, morphology and properties of poly(ethylene-oxide) (PEO)-clay nanocomposites using various imaging techniques. Optical Microscopy, Scanning Electron Microscopy, Environmental Scanning Electron Microscopy and Atomic Force Microscopy are used to image structures on all length scales. Complementary scattering experiments are discussed along with preliminary differential scanning calorimetry and Fourier Transform Infrared spectroscopy results. In particular we investigated the multilayered structures of PEO-Laponite and PEO-Montmorillonite multilayered films made from solution. The shear orientation of a polymer-clay network in solution combined with simultaneous solvent evaporation leads to supramolecular multilayer formation in the film. The resulting …
Crystal Growth And The Search For Highly Correlated Ternary Intermetallic Antimonides And Stannides, Evan Lyle Thomas
Crystal Growth And The Search For Highly Correlated Ternary Intermetallic Antimonides And Stannides, Evan Lyle Thomas
LSU Doctoral Dissertations
This dissertation describes the crystal growth, chemical structures, and efforts made towards the understanding of the physical properties of novel ternary rare-earth intermetallics, which may display signature behavior such as superconductivity, heavy fermion behavior, intermediate valence, and/or large magnetoresistance. To address the problem of correlating these characteristics with structural features, several ternary antimony- and tin-containing phases, Ln-T-X (Ln = lanthanide; T = Co, Ni, Pd; X = Sn, Sb), have been synthesized in single crystalline form by metallic flux-growth methods and characterized by X-ray diffraction. The antimonide compounds LnNi1-xSb2 (Ln = Y, Gd-Tb, Er, Yb), alpha, beta-LnNiSb3 (Ln = La, …
A Community Approach To Identifying Essential Fish Habitat Of Spotted Seatrout, Cynoscion Nebulosus, In Barataria Bay, La, Pamela Sharon Dawn Macrae
A Community Approach To Identifying Essential Fish Habitat Of Spotted Seatrout, Cynoscion Nebulosus, In Barataria Bay, La, Pamela Sharon Dawn Macrae
LSU Doctoral Dissertations
Louisiana wetlands are disappearing at a dramatic rate, providing an impetus for identifying essential fish habitat (EFH) in this region. The distribution, relative abundance, biomass, length and food web dynamics of spotted seatrout, Cynoscion nebulosus, as well as the fish assemblage structure were examined in Barataria Bay, LA, in relation to habitat type and physical/chemical properties of the water. All fish were collected from three sites located along a salinity gradient, each contained the three habitat types of interest: marsh edge, soft bottom and oyster shell, and were sampled monthly from May 2003 to May 2004 with gillnets. Habitat preference …
Ontology-Based Methodology For Error Detection In Software Design, Allyson M. Hoss
Ontology-Based Methodology For Error Detection In Software Design, Allyson M. Hoss
LSU Doctoral Dissertations
Improving the quality of a software design with the goal of producing a high quality software product continues to grow in importance due to the costs that result from poorly designed software. It is commonly accepted that multiple design views are required in order to clearly specify the required functionality of software. There is universal agreement as to the importance of identifying inconsistencies early in the software design process, but the challenge is how to reconcile the representations of the diverse views to ensure consistency. To address the problem of inconsistencies that occur across multiple design views, this research introduces …
Multianalyte Detection Of Breast Cancer By Fabrication Of Hybridmicroarrays On Polymer-Based Microanalytical Devices, Suying Wei
LSU Doctoral Dissertations
Breast cancer is one of the most common and fatal cancer diseases that affect women worldwide. As is true with most other cancer diseases, early detection of breast cancer is very crucial for proper medical treatment because treatment of advanced breast cancer will be much more difficult and inconsistent. Screening and testing of breast cancer biomarkers, either genetic or proteomic, are among techniques used for diagnosis of breast cancers. Nevertheless, none of the biomarkers is by itself sensitive and selective enough for diagnosis of breast cancer, and thus, multi-analyte assays towards detection of multiple breast cancer biomarkers from different classes …
High Harmonic Generation By Short Laser Pulses: Time-Frequency Behavior And Applications To Attophysics, Mitsuko Murakami
High Harmonic Generation By Short Laser Pulses: Time-Frequency Behavior And Applications To Attophysics, Mitsuko Murakami
LSU Doctoral Dissertations
High harmonic generation (HHG) is a process in which noble gas atoms excited by an intense laser field at frequency ω1 emit radiation of higher frequencies that are odd integer multiples of ω1. Driven by an infrared laser, high harmonic radiation can span from the optical into the extreme ultraviolet (XUV) frequency range. In this thesis, I study HHG using short laser pulses by solving the time-dependent Schrödinger equation (TDSE). In particular, I will focus on calculating and controlling the time-dependent instantaneous frequency (chirp) of high harmonics. The harmonic chirp is a direct consequence of the atom-field …
Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi
Integrating Micro-Scale Separations To Matrix Assisted Laser Desorption And Ioniation Time Of Flight Mass Spectrometry (Maldi-Tof-Ms) For Protein Analysis, Harrison K. Musyimi
LSU Doctoral Dissertations
This dissertation describes the integration of micro-scale separations to matrix assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI TOF MS) for protein analysis. MALDI MS provides unsurpassed accurate mass measurements of intact bio-molecules, for example peptides and proteins, which in turn generate high molecular specificity enabling the identity, function and structure of these molecules to be characterized. However, in order to realize the full potential of MS in proteomic studies, integrated sample processing on automated and high throughput platforms is required to address the complexity, diversity and the dynamic range of proteomic analysis. The work described here contributes towards …
Direct Detection Of Homocysteine And Syntheses Of Lanthanide Complexes As Biosensors, Weihua Wang
Direct Detection Of Homocysteine And Syntheses Of Lanthanide Complexes As Biosensors, Weihua Wang
LSU Doctoral Dissertations
At elevated levels, homocysteine (Hcy) is a risk factor for cardiovascular diseases and Alzheimer’s disease. It’s also implicated in a number of other diseases such as neural tube defects, pregnancy complications, and renal failures. The monitoring of Hcy levels in plasma is of current concern. To date, the biochemical mechanism by which Hcy is involved in disease states is unclear. Herein, we describe highly selective colorimetric methods for the direct determination of Hcy. Inexpensive, commercially available materials are reported. The results show potential application for the detection of Hcy in human blood plasma. Additionally, new HPLC postcolumn detection methods for …
Applications Of Titanium-Mediated Reductive Coupling And Cyclocarbonylation Reactions Toward Natural Product Synthesis, Maria A. Appeaning
Applications Of Titanium-Mediated Reductive Coupling And Cyclocarbonylation Reactions Toward Natural Product Synthesis, Maria A. Appeaning
LSU Doctoral Dissertations
Previous work in our laboratory has demonstrated not only a synthetic value of tandem reductive cyclization - carbonylation reactions in the preparation of complex molecules but also the interesting stereoselectivity observed therein. The first part of this work employs the titanium-mediated cyclocarbonylation of tethered dienals for the synthesis of prostaglandin analogues, in particular PGF2α and methyl jasmonate. Based on this hetero Pauson-Khand strategy, we have established an efficient racemic route to both the prostaglandin and the methyl jasmonate core skeletons. Moderate to excellent selectivities with regard to the hetero Pauson-Khand reaction were observed in both cases. The second part …
On Moment Conditions For The Girsanov Theorem, See Keong Lee
On Moment Conditions For The Girsanov Theorem, See Keong Lee
LSU Doctoral Dissertations
In this dissertation, the well-known Girsanov Theorem will be proved under a set of moment conditions on exponential processes. Our conditions are motivated by the desire to avoid using the local martingale theory in the proof of the Girsanov Theorem. Namely, we will only use the martingale theory to prove the Girsanov Theorem. Many sufficient conditions for the validity of the Girsanov Theorem have been found since the publication of the result by Girsanov in 1960. We will compare our conditions with some of these conditions. As an application of the Girsanov Theorem, we will show the nonexistence of an …
Topics In Quantum Topology, Khaled Moham Qazaqzeh
Topics In Quantum Topology, Khaled Moham Qazaqzeh
LSU Doctoral Dissertations
In chapter 1, which represents joint work with Gilmer, we define an index two subcategory of a 3-dimensional cobordism category. The objects of the category are surfaces equipped with Lagrangian subspaces of their real first homology. This generalizes the result of [9] where surfaces are equipped with Lagrangian subspaces of their rational first homology. To define such subcategory, we give a formula for the parity of the Maslov index of a triple of Lagrangian subspaces of a skew symmetric bilinear form over R. In chapter 2, we find two bases for the lattices of the SU(2)-TQFT-theory modules of the torus …
Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy
Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy
LSU Doctoral Dissertations
A number of environmental stressors have been shown to interfere with reproductive and behavioral processes of fish by interfering with endocrine function. Most biomarkers of endocrine disturbance tend to be static measurements from dynamic systems making them difficult to evaluate within the context of an individual, or subtle effects that do not relate well to endpoints of ecological significance. I present an approach that uses a series of models, based on Atlantic croaker, to extrapolate laboratory results to indicators of individual and population health. First, I created a physiologically based model that simulates vitellogenesis in a female fish. The model …
Effects Of An External Field And Dissipation On Decoherence, Jian Zuo
Effects Of An External Field And Dissipation On Decoherence, Jian Zuo
LSU Doctoral Dissertations
Decoherence is the suppression of the interference of quantum states. It plays important roles in the study of the quantum-classical transition. It is also the major obstacle in the implementation of various schemes of quantum computers. Decoherence can be affected by many factors. The interactions between quantum systems of interest and dissipative environments cause the extensively studied environment-induced-decoherence. Decoherence can also occur as the result of a temperature effect. A recent experiment investigated the engineering of decoherence, which involves applying an external field to the quantum system. In this thesis, we study the effect of an external field on decoherence …
Extension Of Shor's Period-Finding Algorithm To Infinite Dimensional Hilbert Spaces, Jeremy James Becnel
Extension Of Shor's Period-Finding Algorithm To Infinite Dimensional Hilbert Spaces, Jeremy James Becnel
LSU Doctoral Dissertations
Over the last decade quantum computing has become a very popular field in various disciplines, such as physics, engineering, and mathematics. Most of the attraction stemmed from the famous Shor period--finding algorithm, which leads to an efficient algorithm for factoring positive integers. Many adaptations and generalizations of this algorithm have been developed through the years, some of which have not been ripened with full mathematical rigor. In this dissertation we use concepts from white noise analysis to rigorously develop a Shor algorithm adapted to find a hidden subspace of a function with domain a real Hilbert space. After reviewing the …
Syntheses And Biological Evaluation Of Water Soluble Carboranylporphyrins For Application In Boron Neutron Capture Therapy, Vijay Gottumukkala
Syntheses And Biological Evaluation Of Water Soluble Carboranylporphyrins For Application In Boron Neutron Capture Therapy, Vijay Gottumukkala
LSU Doctoral Dissertations
The goal of the research presented in this dissertation is to develop novel water soluble carboranylporphyrins that can deliver therapeutic dosage of boron specifically to tumors for application in boron neutron capture therapy. In order to accomplish this goal novel water soluble tetra(nido-carboranyl)porphyrin and the octa(nido-carboranyl)porphyrin with high boron contents are synthesized by the condensation of the carborane substituted benzaldehyde with the pyrrole under acidic conditions. These porphyrins are made water soluble by the deboronation of the closo-carboranes to afford the corresponding amphiphilic nido-carborane cages. The low cytotoxicity, high cellular uptake and intracellular localization of these carboranylporphyrins in tumor cells …
Some Factors Affecting The Interfacial Interaction At Thermomechanical Pulp Fiber And Polypropylene Interphase, Sangyeob Lee
Some Factors Affecting The Interfacial Interaction At Thermomechanical Pulp Fiber And Polypropylene Interphase, Sangyeob Lee
LSU Doctoral Dissertations
This dissertation focused on some selected factors that influence the interfacial interactions at the interphase between wood based materials and thermoplastic surfaces. Several treatments were applied to enhance interfacial properties. In general, interfacial properties were altered by physical and chemical surface modification. Study of the interfacial interactions between wood fiber surfaces as a reinforced material and thermoplastics as a matrix material is important to understand fundamentals of wood fiber-plastic composites (WPC). This study represents fundamental research to define treatment effects on surfaces of wood pulp fibers and polypropylene (PP) film. Two thermosets, ion implantations, and maleic anhydride (MA) grafting were …
Development Of Analytical Techniques For The Analysis Of Submicron Particles And Protein Aggregates, Yohannes H. Rezenom
Development Of Analytical Techniques For The Analysis Of Submicron Particles And Protein Aggregates, Yohannes H. Rezenom
LSU Doctoral Dissertations
The goal of the research presented in this dissertation is to develop analytical techniques for the analysis of heterogeneous mixtures of submicron particles and protein aggregates. In Chapter 2, a simple and reproducible technique for constructing perfectly aligned gaps in fused-silica capillaries has been developed for postcolumn reagent addition with capillary electrophoresis (CE) to take advantage of laser-induced fluorescence (LIF) detection. This technique uses laser ablation with a Nd:YAG laser to create gaps of 14.0 ¡Ó 2.2 ƒÝm. These structures have been used for reagent addition for postcolumn derivatization with LIF detection and have been tested for the separation of …
River, Tidal And Wind Interactions In A Deltaic Estuarine System, Gregg Snedden
River, Tidal And Wind Interactions In A Deltaic Estuarine System, Gregg Snedden
LSU Doctoral Dissertations
The balance between river and marine influences is important in governing landscape sustainability in river deltas. River- and atmospherically driven sea level variability, sediment loading, and estuary-ocean exchange in the Mississippi River delta are examined in this study. Subtidal estuarine sea level variability in the Breton Sound estuary was driven by a combination of remote atmospheric forcing outside the estuary over the continental shelf and controlled river inputs through a gated diversion structure at the estuary head. The highly-frictional deltaic landscape acted as a low-pass filter to coastal fluctuations near the estuary mouth. When substantial quantities river water were discharged …
Classifying Quadratic Number Fields Up To Arf Equivalence, Jeonghun Kim
Classifying Quadratic Number Fields Up To Arf Equivalence, Jeonghun Kim
LSU Doctoral Dissertations
Two number fields K and L are said to be Arf equivalent if there exists a bijection T : ΩK → ΩL of places of K and of L such that KP and LTP are locally Arf equivalent for every place P ε ΩK. That is, |K*p/K*2p| = |L*TP/L*2TP|, type[( , )P] = type[( , )TP], and Arf(rP ) = Arf(rTP ) for every place P ε ΩK, where rP is the local …
Characterization Of Beta-Amyloid Peptide Aggregation And Acceleration With Non-Fibrillar Forming Peptide-Based Mediators, Nadia J. Edwin
Characterization Of Beta-Amyloid Peptide Aggregation And Acceleration With Non-Fibrillar Forming Peptide-Based Mediators, Nadia J. Edwin
LSU Doctoral Dissertations
Protein aggregation occurs under many circumstances, from the dynamic assembly of tubulin to form microtubules, the aggregation of actin into filaments, as well as plaque formation by amyloid precipitation. One important requirement in studying the mechanism of amyloid aggregation is the ability to monitor the growth kinetics over a wide range in size scales (10 nm to microns) with time that spans microseconds to seconds. Understanding the mechanisms of the aggregation may then lead to improved design of drugs to help control or suppress the aggregation process. In this dissertation, the physical characterization of the â-amyloid peptide and its interaction …
Synthesis, Characterization And Properties Of Cooper(Ii) Beta-Diketonate Macrocycles, Sylvester Burton
Synthesis, Characterization And Properties Of Cooper(Ii) Beta-Diketonate Macrocycles, Sylvester Burton
LSU Doctoral Dissertations
This dissertation deals with the synthesis and properties of multidentate β-diketone ligands and their transition-metal complexes. (1) We prepared two bis(β-diketones), C1BAH2 and p-XBAH2 (see sketch below), determined their crystal structures, and studied their reactions with copper(II). We envisioned that they would form macrocyclic complexes with 3-6 metal atoms. In both cases, although the initial products are soluble, as expected for the desired molecular products, we were unable to isolate well-behaved molecular solids. In the case of C1BAH2, this may be because the cyclic product requires an unusual combination of conformations of …
Effective Inter-Organizational Information And Communication Technology Adoption In Business-To-Business Customer Interface, Sanna Maria Kallioranta
Effective Inter-Organizational Information And Communication Technology Adoption In Business-To-Business Customer Interface, Sanna Maria Kallioranta
LSU Doctoral Dissertations
Past research has found that 80-90 percent of IT investments do not meet corporate performance objectives, primarily due to non-technical reasons such as human and organizational aspects. When Inter-organizational Information and Communication Technology (IICT) implementation is properly managed IICT can help manage the flow of goods, services, and information between business partners in the supplier-customer dyad, thus reducing transaction costs along the entire value chain. Using the underlying Resource-Based View theoretical foundation, this research approaches effective IICT implementation capability as a holistic organizational capability that extends beyond tangible IT resources. This research investigates business outcomes of IICT adoption in the …
Synthesis, Crystal Growth, Magnetic And Transport Properties Of Ln-M-X (Ln=Lanthanide, M=Transition Metal, X=In, Ga) Compounds, Willa Maria Williams
Synthesis, Crystal Growth, Magnetic And Transport Properties Of Ln-M-X (Ln=Lanthanide, M=Transition Metal, X=In, Ga) Compounds, Willa Maria Williams
LSU Doctoral Dissertations
ABSTRACT This dissertation focuses on the structural stability, magnetic and transport properties of ternary lanthanide compounds grown using indium and gallium flux. Single crystals of TbRhIn5 were synthesized using indium flux. TbRhIn5 is isostructural to the well known LnnMIn3n+2 (n = 1, 2, ∞; Ln = La, Ce; M = Rh, Ir) and adopts the HoCoGa5 structure type and crystallizes in the space group P4/mmm, Z = 1. Lattice parameters are a = 4.6000(6) Å and c = 7.4370(11) Å, V = 157.29(6) Å3. A sharp antiferromagnetic transition is observed at TN = 48 K for TbRhIn5. Single crystals of …
Quantifying Changes In Fish Habitat Use In Coastal Waters Of Louisiana, Usa: A Hydroacoustic Approach, Kevin Mershon Boswell
Quantifying Changes In Fish Habitat Use In Coastal Waters Of Louisiana, Usa: A Hydroacoustic Approach, Kevin Mershon Boswell
LSU Doctoral Dissertations
The development of reliable tools for identifying essential fish habitat (EFH) has proven problematic. Knowledge of the distribution and biomass of fishes over discrete habitat types is a prerequisite for effective use of EFH in the management of important commercial and recreational fish species. Resolution of the influence of habitat type and environmental factors on the distribution of fishes is confounded by limitations of traditional sampling gears. To date, hydroacoustic technology has been widely accepted as a tool for surveying fishery resources; however few studies have implemented acoustics in ultra shallow (<2 m) coastal waters. Efforts should be made to utilize hydroacoustics for quantifying changes in fish distributions within estuarine environments given the benefits provided through acoustic technology (e.g. ease of deployment, reduced sampling effort, and non-invasive sampling attributes). A technique was developed for acoustically sensing fishes in the shallow, turbid waters of Barataria Bay, Louisiana. A robust and lightweight remotely-controlled transducer platform was designed for deploying acoustic gear. Sources of scattering within the bay were identified through a series of exclosure net experiments designed to quantify potential effects of plankton and suspended solids on acoustic scattering. Analysis filters were developed to reduce the effects of bubble-induced noise, often observed during periods when wind speeds were greater than 4.5 m s-1. Side-aspect acoustic target strength-length and target …
A Neural Network Model For Classification Of Coastal Wetlands Vegetation Structure With Moderate Resolution Imaging Spectro-Radiometer (Modis) Data, Evaristo Joseph Liwa
A Neural Network Model For Classification Of Coastal Wetlands Vegetation Structure With Moderate Resolution Imaging Spectro-Radiometer (Modis) Data, Evaristo Joseph Liwa
LSU Doctoral Dissertations
Mapping coastal marshes is an important component in the management of coastal environments. Classification of marshes using remote sensing data has traditionally been performed by employing either parametric supervised classification algorithms or unsupervised classification algorithms. The implementation of these conversional classification methods is based on the underlying distributions concerning the probability density functions (PDF). Neural networks provide a practical approach to this classification because they are essentially non-parametric data transformations that are not restricted by any underlying assumptions. The major objective of this study was to evaluate the ability of neural networks using Moderate Resolution Imaging Spectro-radiometer (MODIS) data to …
Representation Properties Of Definite Lattices In Function Fields, Jean Edouard Bureau
Representation Properties Of Definite Lattices In Function Fields, Jean Edouard Bureau
LSU Doctoral Dissertations
This work is made of two different parts. The first contains results concerning isospectral quadratic forms, and the second is about regular quadratic forms. Two quadratic forms are said to be isospectral if they have the same representation numbers. In this work, we consider binary and ternary definite integral quadratic form defined over the polynomial ring F[t], where F is a finite field of odd characteristic. We prove that the class of such a form is determined by its representation numbers. Equivalently, we prove that there is no nonequivalent definite F[t]-lattices of rank 2 or 3 having the same theta …
An Inverse Homogenization Design Method For Stress Control In Composites, Michael Stuebner
An Inverse Homogenization Design Method For Stress Control In Composites, Michael Stuebner
LSU Doctoral Dissertations
This thesis addresses the problem of optimal design of microstructure in composite materials. The work involves new developments in homogenization theory and numerical analysis. A computational design method for grading the microstructure in composite materials for the control of local stress in the vicinity of stress concentrations is developed. The method is based upon new rigorous multiscale stress criteria connecting the macroscopic or homogenized stress to local stress fluctuations at the scale of the microstructure. These methods are applied to three different types of design problems. The first treats the problem of optimal distribution of fibers with circular cross section …