Three-dimensional (3D) optical data storage based on two-photon processes provides highly confined excitation in a recording medium and a mechanism for writing and reading data with less cross talk between multiple memory layers, due to the quadratic dependence of two photon absorption (2PA) on the incident light intensity. The capacity for highly confined excitation and intrinsic 3D resolution affords immense information storage capacity (up to 1012 bits/cm3). Recently, the use of photochromic materials for 3D memory has received intense interest because of several major advantages over current optical systems, including their erasable/rewritable capability, high resolution, and high sensitivity. This work demonstrates a novel two-photon 3D optical storage system based on the modulation of the fluorescence emission of a highly efficient two-photon absorbing fluorescent dye (fluorene derivative) and a photochromic compound (diarylethene). The feasibility of using efficient intermolecular Förster Resonance Energy Transfer (RET) from the non-covalently linked two-photon absorbing fluorescent fluorene derivative to the photochromic diarylethene as a novel read-out method in a two-photon optical data storage system was explored. For the purpose of the development of this novel two-photon 3D optical storage system, linear and two-photon spectroscopic characterization of commercial diarylethenes in solution and in a polymer film and evidence of their cyclization (O→C) and cycloreversion (C→O) reactions induced by two-photon excitation were undertaken. For the development of a readout method, Resonance Energy Transfer (RET) from twophoton absorbing fluorene derivatives to photochromic compounds was investigated under one and two-photon excitation. The Förster's distances and critical acceptor concentrations were determined for non-bound donor-acceptor pairs in homogeneous molecular ensembles. To the best of my knowledge, modulation of the two-photon fluorescence emission of a dye by a photochromic diarylethene has not been reported as a mechanism to read the recorded information in a 3D optical data storage system. This system was demonstrated to be highly stable and suitable for recording data in thick storage media. The proposed RET-based readout method proved to be non-destructive (exhibiting a loss of the initial fluorescence emission less than 20% of the initial emission after 10,000 readout cycles). Potential application of this system in a rewritable-erasable optical data storage system was proved. As part of the strategy for the development of diarylethenes optimized for 3D optical data storage, derivatives containing Ï€-conjugated fluorene molecules were synthesized and characterized. The final part of this reasearch demonstrated the photostability of fluorine derivatives showing strong molecular polarizability and high fluorescence quantum yields. These compounds are quite promising for application in RET-based two-photon 3D optical data storage. Hence, the photostability of these fluorene derivatives is a key parameter to establish, and facilitates their full utility in critical applications.

Two-photon absorption (2PA) has been used for a number of scientific and technological applications, exploiting the fact that the 2PA probability is directly proportional to the square of the incident light intensity (while one-photon absorption bears a linear relation to the incident light intensity). This intrinsic property of 2PA leads to 3D spatial localization, important in fields such as optical data storage, fluorescence microscopy, and 3D microfabrication. The spatial confinement that 2PA enables has been used to induce photochemical and photophysical events in increasingly smaller volumes and allowed nonlinear, 2PA-based, technologies to reach sub-diffraction limit resolutions. The primary focus of this dissertation is the development of novel, efficient 2PA, fluorene-based molecules to be used either as photoacid generators (PAGs) or fluorophores. A second aim is to develop more effective methods of synthesizing these compounds. As a third and final objective, the new molecules were used to develop a write-once-read many (WORM) optical data storage system, and stimulated emission depletion probes for bioimaging. In Chapter I, the microwave-assisted synthesis of triarylsulfonium salt photoacid generators (PAGs) from their diphenyliodonium counterparts is reported. The microwave-assisted synthesis of these novel sulfonium salts afforded reaction times 90 to 420 times faster than conventional thermal conditions, with photoacid quantum yields of new sulfonium PAGs ranging from 0.01 to 0.4. These PAGs were used to develop a fluorescence readout-based, nonlinear three-dimensional (3D) optical data storage system (Chapter II). In this system, writing was achieved by acid generation upon two-photon absorption (2PA) of a PAG (at 710 or 730 nm). Readout was then performed by interrogating two-photon absorbing dyes, after protonation, at 860 nm. Two-photon recording and readout of voxels was demonstrated in five and eight consecutive, crosstalk-free layers within a polymer matrix, generating a data storage capacity of up to 1.8 x 1013 bits/cm3. The possibility of using these PAGs in microfabrication is described in Chapter III, where two-photon induced cationic ring-opening polymerization (CROP) crosslinking of an SU8 resin is employed to produce free-standing microstructures. Chapter IV describes the investigation of one- and two-photon stimulated emission transitions by the fluorescence quenching of a sulfonyl-containing fluorene compound in solution at room temperate using a picosecond pump-probe technique. The nature of stimulated transitions under various fluorescence excitation and quenching conditions were analyzed theoretically, and good agreement with experimental data was demonstrated. Two-photon stimulated transitions S1 to S0 were shown at 1064 nm. The two-photon stimulated emission cross section of the sulfonyl fluorophore was estimated as aproximately 240 - 280 GM, making this compound a good candidate for use in two-photon stimulated emission depletion (STED) microscopy.

Sig sigma is a methodology where companies strive to reproduce results ending up having a 99.9996% chance their product will be void of defects. In order for companies to reach six sigma, statistical process control (SPC) needs to be introduced. SPC has many different tools associated with it, control charts being one of them. Control charts play a vital role in managing how a process is behaving. Control charts allow users to identify special causes, or shifts, and can therefore change the process to keep producing good products, free of defects. There are many factories and manufacturing facilities having implemented some sort of statistical process control. St. Jude Medical implemented control charts to monitor different tools on the manufacturing line. How the data is entered and stored poses a difficult situation for the person monitoring the processes. The program used to keep the control charts is not user friendly and difficult to use. Another program can be produced to provide a greater level of efficiency. The goals of this project are to stress how important control charts are in the manufacturing world, what problems are currently seen for operators and supervisors, and how a new and improved program can help fix the current situation. This paper goes into the reasons for the change as well has what has been improved.

Main memory remains a scarce computing resource. Even though main memory is becoming more abundant, software applications are inexorably engineered to consume as much memory as is available. For example, expert systems, scientific computing, data mining, and embedded systems commonly suffer from the lack of main memory availability. This thesis introduces JDiet, an innovative memory management system for Java applications. The goal of JDiet is to provide the developer with a highly configurable framework to reduce the memory footprint of a memory-constrained system, enabling it to operate on much larger working sets. Inspired by buffer management techniques common in modern database management systems, JDiet frees main memory by evicting non-essential data to a disk-based store. A buffer retains a fixed amount of managed objects in main memory. As non-resident objects are accessed, they are swapped from the store to the buffer using an extensible replacement policy. While the Java virtual machine naïvely delegates virtual memory management to the operating system, JDiet empowers the system designer to select both the managed data and replacement policy. Guided by compile-time configuration, JDiet performs aspect-oriented bytecode engineering, requiring no explicit coupling to the source or compiled code. The results of an experimental evaluation of the effectiveness of JDiet are reported. A JDiet-enabled XML DOM parser is capable of parsing and processing over 200% larger input documents by sacrificing less than an order of magnitude in performance.

Amaethon is a web application that is designed for enterprise farm management. It takes a job typically performed with spreadsheets, paper, or custom software and puts it on the web. Farm administration personnel may use it to schedule farm operations and manage their resources and equipment. A survey was con- ducted to assess Amaethon’s user interface design. Participants in the survey were two groups of students and a small group of agriculture professionals. Among other results, the survey indicated that a calendar interface inside Amaethon was preferred, and statistically no less effective, than a map interface. This is despite the fact that a map interface was viewed by some users as a potentially important and effective component of Amaethon.

Contemporary small office phone systems are specialized computers that connect a variety of phones within the office and to the local phone company. These systems use digital signaling processors (DSPs) to convert signals from analog to digital and vice-versa. Many different types of applications run on the DSPs and different businesses have varying application needs. Given the systems have limited amounts of DSP resources and growing numbers of applications for a phone system, an administrator needs a way to configure the uses of resources based on their individual business needs. This thesis provides an overview of a system for configuring resources on various types of DSP hardware some of which are removable and have differing tradeoffs between application uses. The system has to be able to change resource allocations while the phone system is running with minimal interruptions to calls. The configuration system needs to be designed to be flexible enough that new applications or DSP hardware could be supported without major changes to code. This thesis presents a system that uses a database-driven model along with algorithms that optimize configuration of DSP hardware given the administrator’s individual application needs.

Цель работы: разработке универсальный авторскую модель тестирования массивов хранения данных для оптимизации бизнес-процесса тестирования демо-оборудования на предприятии. В соответствии с целью и темой работы, были поставлены следующие задачи: провести литературный обзор на наличие моделей тестирования ИТ-оборудования; исследовать и провести сравнительный анализ существующих моделей тестирования массивов хранения; разработать и описать авторскую универсальную модель тестирования; создать стандартизированный бизнес-процесс тестирования массивов хранения данных; рассмотреть практическую применимость созданной модели на предприятии-заказчике; оценить экономический эффект от внедрения новой модели в бизнес-процесс тестирования. Результат проекта – Разработанная авторская модель тестирования массивов хранения данных. Вклад автора в проект: участие в разработке программы тестирования как работника компании-интегратора, проведение тестирований массивов хранения по разработанной модели. / The purpose of the work: to develop a universal author's model of testing data storage arrays to optimize the business process of testing demo equipment at the enterprise. In accordance with the purpose and topic of the work, the following tasks were set: to conduct a literary review for the availability of IT equipment testing models; to investigate and conduct a comparative analysis of existing storage array testing models; to develop and describe the author's universal testing model; to create a standardized business process for testing storage arrays; to consider the practical applicability of the created model at the customer enterprise; to assess the economic effect of the introduction of a new model into the testing business process. The result of the project is the author's developed model for testing data storage arrays. The author's contribution to the project: participation in the development of the testing program as an employee of the integrator company, testing of storage arrays according to the developed model.

Collaboration has become a key feature of modern software, allowing teams to work together effectively in real-time while in different locations. In order for a user to communicate their intention to several distributed peers, computing devices must exchange high-frequency updates with transient metadata like mouse position, text range highlights, and temporary comments. Current peer-to-peer awareness solutions have high time and space complexity due to the ever-expanding logs that each client must maintain in order to ensure robust collaboration in eventually consistent environments. This paper proposes an awareness Conflict-Free Replicated Data Type (CRDT) library that provides the tooling to support an eventually consistent, decentralized, and robust multi-user collaborative environment. Our library is tuned for rapid iterative updates that communicate fine-grained user actions across a network of collaborators. Our approach holds memory constant for subsequent writes to an existing key on a shared resource and completely prunes stale data from shared documents. These features allow us to keep the CRDT's memory footprint small, making it a feasible solution for memory constrained applications. Results show that our CRDT implementation is comparable to or exceeds the performance of similar data structures in high-frequency read/write scenarios.

This Thesis describes the systematic theoretical study aimed at prediction of the essential properties for the functional organic molecules that belong to diarylethene (DA) family of compounds. Diarylethenes present the distinct ability to change color under the influence of light, known as photochromism. This change is due to ultrafast chemical transition from open to closed ring isomers (photocyclization). It can be used for optical data storage, photoswitching, and other photonic applications. In this work we apply Density Functional Theory methods to predict 6 of the related properties: (i) molecular geometry; (ii) resonant wavelength; (iii) thermal stability; (iv) fatigue resistance; (v) quantum yield and (vi) nanoscale organization of the material. In order to study sensitivity at diode laser wavelengths, we optimized geometry and calculated vertical absorption spectra for a benchmark set of 28 diarylethenes. Bond length alternation (BLA) parameters and maximum absorption wavelengths (λmax) are compared to the data presently available from X-ray diffraction and spectroscopy experiments. We conclude that TD-M05/6-31G*/PCM//M05-2X/6-31G*/PCM level of theory gives the best agreement for both the parameters. For our predictions the root mean square deviation (RMSD) are below 0.014 Å for the BLAs and 25 nm for λmax. The polarization functions in the basis set and solvent effects are both important for this agreement. Next we consider thermal stability. Our results suggest that UB3LYP and UM05-2X functionals predict the activation barrier for the cycloreversion reaction within 3-4 kcal/mol from experimental value for a set of 7 photochromic compounds. We also study thermal fatigue, defined as the rate of undesirable photochemical side reactions. In order to predict the kinetics of photochemical fatigue, we investigate the mechanism of by-product formation. It has been established experimentally that the by-product is formed from the closed isomer; however the mechanism was not known. We found that the thermal by-product pathway involves the bicyclohexane (BCH) ring formation as a stable intermediate, while the photochemical by-product formation pathway may involve the methylcyclopentene diradical (MCPD) intermediate. At UM05-2X/6-31G* level, the calculated barrier between the closed form and the BCH intermediate is 51.2 kcal/mol and the barrier between the BCH intermediate and the by-product 16.2 kcal/mol. Next we investigate two theoretical approaches to the prediction of quantum yield (QY) for a set of 14 diarylethene derivatives at the validated M05-2X/6-31G* theory level. These include population of ground-state conformers and location of the pericycylic minimum on the potential energy surface 2-A state. Finally, we investigate the possibility of nanoscale organization of the photochromic material based on DNA template, as an alternative to the amorphous polymer matrix. Here we demonstrate that Molecular Dynamic methods are capable to describe the intercalation of π-conjugated systems between DNA base pairs and accurately reproduced the available photophysical properties of these nanocomposites. In summary, our results are in good agreement with the experimental data for the benchmark set of molecules we conclude that Density Functional Theory methods could be successfully used as an important component of material design strategy in prediction of accurate molecular geometry, absorption spectra, thermal stability of isomers, fatigue resistance, quantum yield of photocyclization and photophysical properties of nanocomposites.

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