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Remote sensing of radiative fluxes and heating rates from satellite instrument measurements

Weather and climate models are required to calculate radiative fluxes and shortwave heating and longwave cooling rate profiles on a large scale. Heating and cooling rates describe the effect that different configurations of temperature, radiatively active gases, and clouds have on the rates of interlayer energy exchange and affect circulation patterns. Meanwhile, a suite of satellite-based instruments from the NASA Earth Observing System’s A-Train provide an unprecedented set of measurements that can be used to produce quantities that can also yield radiative fluxes and heating and cooling rates. This work explores the extent to which passive-infrared hyperspectral measurements such as those made by the Atmospheric Infrared Sounder impart information towards infrared cooling rates. Several novel methods are explored for interpreting and retrieving cooling rates using spectral measurements.

Transient response of uniform beams

Several special topics relating to the transient flexural vibrations of a uniform beam predicted by the usual elementary or Bernoulli-Euler equation are discussed. The effect on the beam response of the concentration of an applied transient force in space and in time is studied. In the case of an applied step force, it is shown that the dynamic team response can be larger than twice the response to an equal force statically applied. It is demonstrated that the beam response in the higher modes is independent of the boundary conditions.

Modeling artificial, mobile swarm systems

Swarm intelligence is a new research paradigm that offers novel approaches for studying and solving distributed problems using solutions inspired by social insects and other natural behaviors of vertebrates. In this thesis, we present methodologies for modeling artificial, mobile systems within the swarm intelligence framework. The proposed methodologies provide guidelines in the study and design of artificial swarm systems for the following two classes of experiments: distributed sensing and distributed manipulation.

Robotics training algorithms for optimizing motor learning in spinal cord injured subjects

The circuitries within the spinal cord are remarkably robust and plastic. Even in the absence of supraspinal control, such circuitries are capable of generating functional movements and changing their level of excitability based on a specific combination of properceptive inputs going into the spinal cord. This has led to an increase in locomotor training, such as Body Weight Support Treadmill training (BWST) for spinal cord injured (SCI) patients. However, today, little is known about the underlying physiological mechanisms responsible for the locomotor recovery achieved with this type of rehabilitative training, and the optimal rehabilitative strategy is still unknown.

Protein-ligand interactions: docking, design and protein conformational change

Virtual ligand screening has proven to be a successful strategy in drug design. An in house-developed procedure (HierDock), a coarse grain docking method followed by a fine grain search procedure, was used to determine the binding site for sugars in the outer membrane protein A in E.coli, a key interaction in the pathogenesis of neonatal meningitis. These results are being further extended in suggesting possible peptide antagonists and drugs for therapeutic strategies.

Alternative models for air pollutant effects on visibility

Air pollution causes visibility reduction in urban areas such as Los Angeles as well as in national parks and wilderness areas. In this work, alternative mathematical models are formulated that relate air pollutant emissions or ambient air pollutant concentrations to visual range or to changes in the appearance of a scenic vista.

Integration of optoelectronics and microfluidics for biological and chemical sensing

Over the past decade, rapid advances in microfluidics have led to the creation of valves, pumps, mixers, multiplexers, along with a large variety of other devices. This technology has allowed for many fluidics applications to be performed on a chip that is approximately an inch square in area. Such applications include cell sorting, PCR on chip, crystal growth, combinatorial mixing and many others. Although the complexity of these devices may seem overwhelming, they are based on simple process called multilayer soft lithography, which uses a silicone-based elastomer to create these amazing devices. However, with the current state of technology, the applications are somewhat limited. New devices need to be created to further such fields as fluidic logic and biomimetics.

An improved scheme for detection and labeling in Johansson displays

Consider a number of moving points, where each point is attached to a joint of the human body and projected onto an image plane. Johannson showed that humans can effortlessly detect and recognize the presence of other humans from such displays. This is true even when some of the body points are missing (e.g. because of occlusion) and unrelated clutter points are added to the display. We are interested in replicating this ability in a machine.

Models of visual feature detection and spike coding in the nervous system

We propose mathematical models to analyze two nervous system phenomena. The first is a model of the development and function of simple cell receptive fields in mammalian primary visual cortex. The model assumes that images are composed of combinations of a limited set of specific visual features and that the goal of simple cells is to detect the presence or absence of these features. Based on a presumed statistical character of images and their visual features, the model uses a constrained Hebbian learning rule to discover the structure of the features, and thus the appropriate response properties of simple cells, by training on a database of photographs. The response properties of the model simple cells agree qualitatively with neurophysiological observation.

Processing of internal level differences in the auditory brainstem of the barn owl

Nervous systems process information about the environment in order to generate adaptive behavior. Sensory information that is obtained through different modalities, gleaned from different interactions of the animal with its surroundings, generated by different neural algorithms, or used to infer different distal stimulus properties, is often processed by distinct pathways in the brain. The auditory system compares sounds at the two ears in order to derive the location of the source. In the barn owl, Tyto alba, this is accomplished by interaural comparisons of the time that a sound reaches each ear, and of the level (intensity) at each ear. Interaural time differences code for horizontal positions of sound sources while interaural level differences, due to a vertical asymmetry in the owl's ears, can encode the vertical position of a sound. These two cues together can assign unique locations to sound sources in space. The barn owl processes time- and level differences in separate neural channels that converge in the inferior colliculus. This structure is the first site of neurons with spatially restricted auditory receptive fields, and with a neural map of auditory space. Downstream projections from here provide the sensory input for accurate sound localization by saccadic head movements.

Blood flow effects on heart development and a minimally invasive technique for in vivo flow alterations

A series of experiments were conducted on zebrafish (Danio rerio) in order to gain a better understanding of how blood flow and blood flow related forces, such as shear stress, affect vertebrate heart development. Zebrafish were used as a model due to their external fertilization and optical accessibility to the heart and vasculature. The flow field inside the 4.5 day post fertilization (dpf) embryo was analyzed using a combination of manual particle tracking and digital particle image velocimetry (DPIV) software. Our results present the first case of intracardiac microscale DPIV. Additionally, a minimally invasive and reversible technique of delivering and localizing magnetic microspheres inside the vasculature of the embryo was developed. The results of blocked flow induced with this method were compared with previous experiments and controls.

The sea urchin regulome in development

During development an organism undergoes many rounds of pattern formation, generating ever greater complexity with each ensuing round of cell division and specification. The instructions for executing this process are encoded in the DNA, in cis-regulatory modules that direct the expression of developmental transcription factors and signaling molecules.

Districting principles and democratic representation

Redistricting is always political, increasingly controversial, and often ugly. Politicians have always fought tooth-and-nail over district lines, while the courts, for most of their history, considered the subject a thicket too political even to enter.

Districting principles and democratic representation

Redistricting is always political, increasingly controversial, and often ugly. Politicians have always fought tooth-and-nail over district lines, while the courts, for most of their history, considered the subject a thicket too political even to enter.

Edward Lewis and radioactive fallout: the impact of Caltech biologists on the debate over nuclear weapons testing in

The work of Caltech biologists, particularly, Edward Lewis, on leukemia and ionizing radiation transformed the public debate over nuclear weapons testing. The United States began testing hydrogen bombs in 1952, sending radioactive fallout around the globe. Earlier more localized fallout was generated starting in 1945 from tests of atomic weapons at Nevada test sites. The Atomic Energy Commission claimed the tests would not harm human health.

Nonlinear analysis of Pacoima Dam with spatially nonuniform ground motion

Spatially uniform ground motion is an assumption that has often been made for structural analysis of arch dams. However, it has been recognized for many years that the ground motion in a canyon during an earthquake is amplified at the top of the canyon relative to the base. Pacoima Dam has been strongly shaken by the 1971 San Fernando earthquake and the 1994 Northridge earthquake. The acceleration records from both of these events demonstrate the spatial non uniformity of the ground motion, but the amount and quality of the data made it difficult to study in detail. An opportunity to do so arose on January 13, 2001, when a relatively small magnitude 4.3 earthquake was recorded by an upgraded accelerometer array at Pacoima Dam.

Steric and electrostatic repulsions in the inhibition of alpha-chymotrypsin catalysed hydrolyses by indole derivat

The enzyme-inhibitor dissociation constants, i.e., [...], were evaluated for the six isomeric pairs of C-substituted indolecarboxylate ions and carboxamides. The variation of [...] with the position and nature of the substituent indicates that the enzyme-indole complex exhibits a high degree of steric hindrance near the 4 position of the indole ring and electrostatic repulsion due to a negative group near the indole nitrogen.

Unification of quantum information theory

We present the unification of many previously disparate results in noisy quantum Shannon theory and the unification of all of noiseless quantum Shannon theory. More specifically we deal here with bipartite, unidirectional, and memoryless quantum Shannon theory. We find all the optimal protocols and quantify the relationship between the resources used, both for the one-shot and for the ensemble case, for what is arguably the most fundamental task in quantum information theory: sharing entangled states between a sender and a receiver. We find that all of these protocols are derived from our one-shot superdense coding protocol and relate nicely to each other. We then move on to noisy quantum information theory and give a simple, direct proof of the "mother" protocol, or rather her generalization to the Fully Quantum Slepian-Wolf protocol(FQSW). FQSW simultaneously accomplishes two goals: quantum communication-assisted entanglement distillation, and state transfer from the sender to the receiver. As a result, in addition to her other "children," the mother protocol generates the state merging primitive of Horodecki, Oppenheim, and Winter as well as a new class of distributed compression protocols for correlated quantum sources, which are optimal for sources described by separable density operators. Moreover, the mother protocol described here is easily transformed into the so-called "father" protocol, demonstrating that the division of single-sender/single-receiver protocols into two families was unnecessary: all protocols in the family are children of the mother.

On the embedding of homeomorphisms on the plane in flows

Homeomorphisms of the plane onto itself are studied, subject to the restriction that they should preserve the sense of orientation and have no fixed points. The author tries to determine which mappings in this general class can be embedded in one-parameter subgroups of the full homeomorphism group of the plane. Such subgroups are called flows.

Air pollution at the single-particle level: integrating atmospheric measurements with mathematical models

Particulate air pollution is of growing concern in the United States and around the world. Elevated concentrations of aerosols (solid particles and liquid droplets suspended in air) are correlated with increased cases of lung cancer, cardiopulmonary disorders, and human mortality. A detailed understanding of the size, chemical composition, and concentration of atmospheric particles is needed to assess their effects on human health, as well as on regional visibility and global climate. One can acquire such knowledge through direct measurements, or by utilizing mathematical air quality models. New and innovative instruments allow us to measure the size and composition of individual particles, rather than to infer aerosol chemical properties from bulk particulate matter samples. Concurrently, air quality models have been developed to numerically simulate the emissions of discrete particles, and their transport and chemical evolution in the atmosphere. This thesis focuses on how to integrate and compare measurements taken by state-of-the-science single-particle instruments with the air pollutant properties calculated using state-of-the-science mathematical models. A 1996 field experiment conducted in the Los Angeles air basin serves as the case study for this thesis research.

An experimental and theoretical investigation of two dimensional centrifugal pump impellers

An experimental and theoretical investigation on a series of three centrifugal pump impellers has been made in order to determine the usefulness and validity of tyro-dimensional potential theory for the description of the flow. Computed values of the developed head and distribution of pressure on the vane surfaces are compared with measurements an two-, four-, and six- bladed impellers which have 30[degree] logarithmic spiral vanes and a radius ratio of about one-half.

Electrical Engineering ebook : Complexity of information extraction

This thesis describes a mathematical theory that interrelates the basic concepts of complexity, cost, information and reliability. The accessibility of information, as opposed to its availability, is characterized. Universal bounds for complexity distribution, implementation cost and decision reliability are estimated. These bounds give rise to a methodology for any consistent definition of a complexity measure. The basic notions of pattern recognition and information theory are directly related to computational complexity.

Chemical Engineering ebook: The production of percholoric acid

Due to the fact that perchloric acid resembles sulfuric acid in many respects without having many of the disadvantages of use possessed by the latter, the devising of a cheaper means of producing it would be well warranted by its increased use in both analytical and industrial work. The present work was undertaken with the above idea in view and consisted in studying quantitatively the reaction taking place between nitric oxide (NO), nitric acid, and ammonium perchlorate.

Aeronautics Ebooks: Discharge plasma processes of ring-cusp ion thrusters

Aeronautics Ebooks: Discharge plasma processes of ring-cusp ion thrusters
This study has increased the viability of miniature ion thruster technology, advanced state-of-the-art discharge modeling, and revealed important aspects of discharge plasma processes. These extensions of existing ion thruster technology and understanding are necessary to fulfill the needs of future space missions. Experimental comparisons of the discharge performance of an array of miniature (3cm diameter) ion thruster discharge configurations were conducted and showed that a 3-ring configuration with length-to-diameter of 1.0 exhibited the best performance. A compact and lightweight version of this configuration, using small accelerator grid holes, exhibited discharge losses of 250-550eV/ion and propellant efficiency of as much as 87%. This performance represents a significant advancement in miniature (less than 5cm diameter) ion thruster technology and demonstrates that a miniature ion thruster of low magnet and thruster weight can yield desirable performance.

Business Ebooks: Managing Inventory Systems with Technology Innovations

In the “faster, better, and cheaper” information age, rapid technological breakthroughs create significant risks of obsolescence at the product level or the component level. Consequently, enormous challenges in jointly coordinating inventory replenishment and technology selection arise. The purpose of this dissertation is to develop analytical models to study technology selection and inventory replenishment joint optimization in inventory systems that face frequent technology innovations.

Architecture E-books: Design and Construction Evaluation of a Photovoltaic DC LED Lighting System

The market demand for commercialization of Photovoltaic (PV) systems depends a lot on the reliability, efficiency and performance of various components within the system. PV panels produce DC power when exposed to sunlight, and an inverter converts this to AC power in a typical solar powered building. Though stand-alone PV lighting systems have existed for a long time it hasn’t been very efficient in the past. Incandescent light sources were commonly used with traditional PV lighting systems which are inefficient. Today, fluorescent fixtures are mostly used with PV’s due to its high efficacy.

Computer Science Ebooks: Synthesizing and Evaluating Data-Driven Motion Transitions

Animation is a sequence of images that people perceive as a continuous movement. These images could be hand-drawn or computer generated. Computer animation starts with models of objects then generates from the models sequences of images. Computer animation is widely used in video games and special effects in films. It also has many applications outside of entertainment such as learning and training in virtual environment, education, and information visualization.

Accounting Ebooks: Individual Investor Reaction to the Earnings Expectations Path and its Components

The Securities and Exchange Commission and popular press have expressed concern that corporations guide analysts’ forecasts with the purpose of managing> earnings surprises and producing desired market reactions. Evidence suggests that firms that guide analysts’ forecasts downward during the period and then beat the latest forecast earn a market premium. Furthermore, alternative paths by which earnings expectations evolve over the reporting period are associated with differential valuation consequences. In an experiment, I explore potential explanations (rooted in judgment effects) for observed market reaction patterns to the earnings expectations path and its components. I conjecture that the presence of uncertainty affects investor reaction to the expectations path in predictable ways. I further examine how investors respond to analyst forecasts and forecast revisions in forming their own earnings expectations. I find that investors are more pessimistic than analysts in their earnings expectations. Further, the divergence between investors’ and analysts’ expectations plays an important role in their reaction. My finding of a premium to beating the latest forecast appears to stem directly from the difference between the investors’ own expectations and the analysts’ consensus forecast. Because investors tend to be more pessimistic than the analysts, they perceive a positive (negative) earnings surprise to be larger (smaller) than reported which explains why investors appear to reward positive earnings surprises more than they penalize negative earnings surprises.

Aeronautics Ebook: Mixing in gas phase turbulent jets

This free ebooks is an experimental investigation of the mixing of the nozzle fluid of a round, turbulent jet with the entrained reservoir fluid, using laser-Rayleigh scattering methods. The measurements, at Reynolds numbers of 5,000 and 16,000, cover the axial range from 20 to 90 jet exit diameters and resolve the full range of temporal and spatial concentration scales. The measured mean and rms values of the concentration, and the mean scalar dissipation rate, when estimated from the time derivative of concentration, are consistent with jet similarity laws. Concentration fluctuation power spectra are found to be self-similar along rays emanating from the virtual origin of the jet, and are consistent with the universal form of scalar spectra proposed by Gibson (1968 II). The probability density functions for the concentration, the time derivative of concentration, and the square of the time derivative of concentration, are compiled and are also found to be self-similar along rays. Features of the measured distributions and spectra are consistent with the existence of large-scale structures within the flow that span the local diameter of the jet's turbulent cone. On the centerline of the jet, the scaled probability density function of jet gas concentration is found to be almost independent of the Reynolds number while the local mixing rate in the inner part of jet is not. The usual assumptions concerning isotropy and correlation of derivatives are found to lead to erroneous results for the probablility density function of the scalar dissipation rate.

Accounting Ebook: Accounting for Business Combinations: A Test for Long-Term Market Memory

The purpose of this research is to examine whether accounting methods for business combinations (purchase and pooling of interests accounting) have a different effect on firms’ market value of equity in the combination year and thereafter. In particular, after the accounting method is no longer disclosed in the financial statements, does it have an impact on market value of equity of the combined firms because the accounting figures are different? A five-year period subsequent to a particular business combination is used because public companies are not required to disclose the details of the combination for more than three years after the effective date of the combination. This research, thus, tests whether market participants still take into consideration the accounting method of past business combinations when this information is no longer disclosed in the financial statements. In addition to the testing of the impact of the accounting methods, the value-relevance of goodwill amortization is investigated.

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