147 research outputs found
Stationary Automata
In this dissertation, we investigate new automata, we call it stationary automata or ST-automata. This concept is based on the definition of TF-automaton by Wojciechowski [Woj2]. What is new in our approach is that we incorporate stationary subsets of limit ordinals of uncountable cofinality. The first objective of the thesis is to motivate the new construction of automata. This concept of ST-automata allows us to make a connection with infinite graph theory. Aharoni, Nash-Williams, and Shelah [AhNaSh] formulated a condition that is necessary and sufficient for a bipartite graph to have a matching. For a bipartite graph G=( M,W,E ) , we define a language over the alphabet { M,W } . We construct an ST-automaton such that for each bipartite graph G, the automaton accepts an element of if and only if G has no matching. The theorem of Aharoni, Nash-Williams, and Shelah [AhNaSh] is used to prove that has the above property. The second objective is to compare the new ST-automata to TF-automata defined by Wojciechowski [Woj2]. First, adding an extra condition, we define special ST-automata and prove that they are equivalent to TF-automata. Then we show that in general ST-automata are stronger. We give an example of a language accepted by an ST-automaton that is not accepted by any special ST-automaton. In chapter four, we define operations on ST-automata over a fixed alphabet I as union, intersection, concatenation, raising to the powers, ω , *, and #. We show that applying those operations to languages defined by ST-automata the obtained languages are also definable using ST-automata
Immunogenetic Basis of Cholecystitis
Cholecystitis is an inflammation of the gallbladder caused by many causes like stone that is cholesterol gallstone and sometimes the cause is due to bacterial infection also known as acalculous cholecystitis. The risk factors for this disease are female, 40, fatty, fair, aging, diabetes mellitus, pregnancy, oral contraceptive and the most common factor is the interaction between genetic and environmental factors. Genetic factors include human leukocyte antigens, ethnicity, race and single nucleotide polymorphism in genes involved in the synthesis of cholesterol, transport and excretion
Faecal Incontinence and Autoimmune Diseases
Fecal incontinence is an embarrassing social problem to the patients affecting patients’ work and social ordinary life. It affects both sexes characterized by inability to control bowel motions causing leaking stool or flatus unexpectedly from the rectum and anus, and in severe cases, it causes a complete loss of bowel control. The causes are severe diarrhea, constipation, muscle and nerve damage that is caused by aging, vaginal delivery, episiotomy or forceps delivery. Anal and rectal continence depends on many aspects like consistency of stool, neuromuscular sphincter complex, rectal capacity, sensation of defecation and ability to move and reach a toilet. Another cause is immunological disorders that cause muscle damage due to formation of autoantibodies in autoimmune diseases or in association with gastrointestinal manifestation of autoimmune diseases like multiple scleroses and other autoimmune diseases. Simply, it can be diagnosed by routine digital rectal examination that has good sensitivity and poor specificity in discriminating small from severe anal sphincter defects
An Investigation of the Relationship between Writing Achievement and Writing Strategy Use by Secondary School Students
Basically, this study aims to identify the extent to which Iraqi secondary school students use writing strategies and how proficiency level and students' gender could affect writing strategy use. The study also examines the relationship between writing achievement and writing strategy use among Iraqi secondary school students. For this purpose, 140 Iraqi secondary school students were selected randomly from six different schools. Petric and Czarl’s questionnaire (2003) was adopted in the study as an instrument to collect the needed data. A software of SPSS used to analyze the collected data. The findings revealed that secondary school students appeared as low users of writing strategies; low proficient students do not show a statistically significant difference compared to high proficient students, female students use more strategies compared to male students do. The study also found a positive correlation between writing strategy use and writing achievement
Effect of Thermal Annealing on the Structural, Optical, and Electrical Properties of a-Se Thin Films
In this experimental study, Structural, electrical and optical properties of as-grown and annealed films for the amorphous Selenium was carried out. Growing for the samples was done on glass substrates by thermal evaporation technique under pressure range 10-5 - 10-6 Torr at room temperature. The structure of amorphous Selenium thin film was investigated by X-ray diffraction (XRD) for three different annealing temperatures (323, and 363K). The result of the X-ray diffraction studied at 363K indicated the formation of Selenium with Hexagonal Phase. The transmission spectra of annealed and as-deposited films have been carried out for the range UV-Visible transmittance spectrum (wavelength range of 200-1100 nm) at room temperature. Results showed that the absorption coefficient for the previous range was . Results for the optical band gap gave a direct one, within the energy range (2.01-2.11) eV. These experimental values of the optical band gap indicated an inversely proportionated with annealing temperature. Results for both D.C and A.C conductivity for the temperature range 295.5 to 363K showed that both type of conductivity related linearly temperature. Results showed that the A.C. conductivity increases linearly with the frequency at the range ( - ) Hz. Results for the activation energy ( ) shows that it related linearly with the annealing temperature. Keywords: Amorphous Selenium, Chalcogenide, X-Ray diffraction (XRD)
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