Physical Sciences and Mathematics Commons^™

Epsilon Precedence Grammars And Languages, Masoud T. Milani

Retrospective Theses and Dissertations

The classes of simple and weak precedence grammars are generalized to include ε-rules (productions with the empty right parts). The descriptive power of epsilon simple precedence (ESP) grammars increases directly with the number of ε-rules permitted; the class of ESP grammars with no ε-rules, ESP₀, is identical to the class of simple precedence grammars; ESP grammars with at most one ε-rule, ESP₁, define a class of languages which properly includes the class of ESP₀ languages, but is itself properly included in the class of deterministic, context-free languages. In general, ESP grammars having at most i …

Ion Selective Electrodes Based On Aza- Substituted Crown Ethers, Lisa Ann Wellington

Retrospective Theses and Dissertations

A cation-responsive electrode system has been developed which incorporates aza-substituted crown ethers as ligands. In a novel application, uncomplexed crown ethers were used in the pelletized form for ionic transport. Electrodes have been produced which can be conditioned for a particular ion and following their use, be reconditioned and reused for other ions. Preparation method and lifetime studies are included.

The responses of two crown ethers with plasticizers were evaluated for thirteen representative cations. The concentration range covered in each evaluation was 1 x 10^-1 to 1 x 10^-7 M. For those ions exhibiting Nernstian or near-Nernstian response, …

Intra Region Routing, Robert Alan Eustace

Retrospective Theses and Dissertations

The custom integrated circuit routing problem normally requires partitioning into rectangular routing regions. Natural partitions usually result in regions that form both "channels" and "areas". This dissertation introduces several new channel and area routing algorithms and measures their performance.

A formal description of the channel routing problem is presented and a relationship is established between the selection of intervals for each track and the number of tracks in the completed channel. This relationship is used as an analysis tool that leads to the development of two new and highly effective channel routing algorithms: the Revised and LCP algorithms. The performance …

The Effects Of Trace Organic Carbon On Aluminum Solubility, Fernand J. Tiblier

Retrospective Theses and Dissertations

Alum jar tests were performed on raw portable waters of varying TOC. Parameters monitored include alum dose, pH and mixing conditions. Finished waters were analyzed for residual aluminum, residual TOC and hardness in order to investigate the effects of TOC on aluminum residual as would be encountered by alum coagulation and lime softening process in practice.

Three-dimensional graphs of residual aluminum, residual TOC and pH were constructed to illustrate the relationship among these measured parameters for the different sources. Statistical analyses were conducted to verify aluminum-organic complexation at reduced alum dosages for varying TOCs; initial TOC, reaction pH and dose …

Perfect Numbers And Mersenne Primes, Barry A. Delello

Retrospective Theses and Dissertations

No abstract provided.

The Use Of Scheffe-Equivalent Equations To Predict Physical Properties Of Neoprene, Cheng Y. Loh

Retrospective Theses and Dissertations

The goal of this study is to find a more organized and directed approach to build models for mixture systems. An attempt is made to generate and then compare Scheffe (mixture) models with those generated by McGee using the ‘conventional’ method for neoprene data. The models are judged on their ability to predict physical properties of neoprene by comparing the following: predicted and actual values by inspection; the calculated % error of prediction; the squared multiple correlation coefficients; adjusted squared multiple correlation coefficients; the Fisher statistic and significance probability. Scheffe models do not have an intercept term and test statistics …

Multiprocessor Scheduling With Practical Constraints, Kenneth Burton Donovan

Retrospective Theses and Dissertations

The problem of scheduling tasks onto multiprocessor systems has increasing practical importance as more applications are being addressed with multiprocessor systems. Actual applications and multiprocessor systems have many characteristics which become constraints to the general scheduling problem of minimizing the schedule length. These practical constraints include precedence relations and communication delays between tasks, yet few researchers have considered both these constraints when developing schedulers.

This work examines a more general multiprocessor scheduling problem, which includes these practical scheduling constraints, and develops a new scheduling heuristic using a list scheduler with dynamically computed priorities. The dynamic priority heuristic is compared against …

Flow Injection And Photometric Determination Of S(Iv) In Rainwater With Pararosaniline, Frank A. Hedgecock

Retrospective Theses and Dissertations

The photometric pararosaniline (pRA) method for determination of S(IV) has been adapted to flow injection sample processing (FIA). Prominent features of the method include a limit of detection of 0.010 ppm of dissolved sulfur dioxide and a sampling rate of 20 per hour. The concentration range investigated was 0.010 to 0.200 ppm S0₂. Sequential samples were collected from two rainstorms and SO₂ concentrations were measured for 19 samples. The suppression of interference by Cr(III), Mn(II), and Fe(III) using 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA) was investigated. A comparison of the adapted FIA method and its parent …

New Synthetic Applications Of Enaminoketones, Timothy J. Buck

Retrospective Theses and Dissertations

This report discusses research concerning synthetic applications of enaminoketones. The work may be divided into four parts as follows: a) replacement of the dimethylamino group of certain enaminones by other amine groups through a simple procedure; b) formation of 3-alkyl-pyrazoles; c) formation of 2-amino-4-alkyl-pyrimidines; d) synthesis and subsequent reduction of iminium salts. The starting materials (E-1-(N,N-dimethylamino)-1-alkene-3-ones) have been condensed with hydrazine and guanidine to form pyrazoles and pyrimidines, respectively. The same starting materials have been reacted with POCl₃ in CH₂Cl₂ to produce chlorovinyliminium salts. These have then been reacted in situ with reducing agents to produce …