Digital Commons Network^™

Simulation Of Creep In Nickel Based Single Crystal Superalloys, Yunhong Pang

Dissertations

Nickel based single crystal Superalloys are finding wide spread use in high temperature gas turbines and other similar applications because of their superior high-temperature strength and creep properties as compared to the other materials. This is due to two factors: solid solution and precipitation strengthening of the gamma (γ) and gamma prime (γ') phases, and the elimination of grain boundaries. Creep of Nickel based single crystal Superalloys are caused by two primary mechanisms, dislocation creep and diffusion creep. Several factors that affect the creep life of Nickel based single crystal Superalloys are the specific microstructure, stress, temperature and rafting. Also, …

Security Information Management With Frame-Based Attack Presentation And First-Order Reasoning, Wei Yan

Dissertations

Internet has grown by several orders of magnitude in recent years, and this growth has escalated the importance of computer security. Intrusion Detection System (IDS) is used to protect computer networks. However, the overwhelming flow of log data generated by IDS hamper security administrators from uncovering new insights and hidden attack scenarios. Security Information Management (SIM) is a new growing area of interest for intrusion detection. The research work in this dissertation explores the semantics of attack behaviors and designs Frame-based Attack Representation and First-order logic Automatic Reasoning (FAR-FAR) using linguistics and First-order Logic (FOL) based approaches. Techniques based on …

Scheduling Policies For Disks And Disk Arrays, Chang Liu

Dissertations

Recent rapid advances of magnetic recording technology have enabled substantial increases in disk capacity. There has been less than 10% improvement annually in the random access time to small data blocks on the disk. Such accesses are very common in OLTP applications, which tend to have stringent response time requirements. Scheduling of disk requests is intended to improve their response time, reduce disk service time, and increase disk access bandwidth with respect to the default FCFS scheduling policy.

Shortest Access Time First policy has been shown to outperform other classical disk scheduling policies in numerous studies. Before verifying this conclusion, …

Image Watermarking, Steganography, And Morphological Processing, Yi-Ta Wu

Dissertations

With the fast development of computer technology, research in the fields of multimedia security, image processing, and robot vision have recently become popular. Image watermarking, steganogrphic system, morphological processing and shortest path planning are important subjects among them. In this dissertation, the fundamental techniques are reviewed first followed by the presentation of novel algorithms and theorems for these three subjects.

The research on multimedia security consists of two parts, image watermarking and steganographic system. In image watermarking, several algorithms are developed to achieve different goals as shown below. In order to embed more watermarks and to minimize distortion of watermarked …

Collaborative Examinations In Asyncronous Learning Networks : Field Experiments On Collaborative Learning Through Online Assessments, Jia Shen

Dissertations

With the proliferation of computer networks and the emergence of virtual teams, learning and knowledge sharing in the online environment has become an increasingly important topic. Applying constructivism and collaborative learning theories to assessment, the collaborative online exam is designed featuring students' active participation in various phases of the exam process through small group activities online. A participatory online exam process is designed featuring similar procedures except that students' involvement in each phase of the exam is individual. The collaborative online exam and the participatory online exam are investigated regarding student exam study strategies, group process, exam outcomes, faculty satisfaction, …

Bioinformatics Study Of Mammalian Mrna Polydenylation, Haibo Zhang

Dissertations

Messenger RNA polyadenylation is one of the key post-transcriptional events in mammalian cells, which have influences on many aspects of mRNA metabolism. Several human diseases have been shown to associate with abnormal polyadenylation, highlighting the importance of this process. The availability of the complete sequence of human and mouse genomes, together with their gene expression data provides valuable resources to study mRNA polyadenylation on a system level. This dissertation addresses the following issues of mammalian mRNA polyadenylation through bioinformatics approaches: (1) the extensive documentation of several key aspects of polyadenylation sites in humans and mice on a genomic level; (2) …

Gas Fluidization Of Nanoparticles, Qun Yu

Dissertations

The primary objective of this study is to perform a systematic investigation on the gas fluidization of various nanoparticle agglomerates. Firstly, the gas fluidization characteristics and regime classifications without any additional external force fields are identified using both experimental measurements and modeling. Secondly, the effect of introducing certain external force fields on nanoparticle fluidization is experimentally investigated. Two external force fields were applied: sound waves from a loud speaker (acoustic assistance) and in-bed magnets that were excited by an external oscillating magnetic field (magnetic assistance). Thirdly, exploratory experimental research on the use of nanoparticle agglomerates as a granular filtration media …

The Control Of Frequency Of A Conditional Oscillator Simultaneously Subjected To Multiple Oscillatory Inputs, Christina L. Ambrosio

Dissertations

A conditional oscillator is one that requires input to oscillate. An example of such is the gastric mill network of the stomatogastric ganglion of the crab Cancer borealis which requires modulatory input from outside the stomatogastric ganglion and fast input from the pyloric network of the animal in order to become active. This dissertation studies how the frequency of the gastric mill network is determined when it is simultaneously subjected to two different rhythmic inputs whose timing may be mismatched. We derive a mathematical model of the gastric mill network and deduce that the difference in timing between the pyloric …

A Versatile Programming Model For Dynamic Task Scheduling On Cluster Computers, Dejiang Jin

Dissertations

This dissertation studies the development of application programs for parallel and distributed computer systems, especially PC clusters. A methodology is proposed to increase the efficiency of code development, the productivity of programmers and enhance performance of executing the developed programs on PC clusters while facilitating improvement of scalability and code portability of these programs. A new programming model, named the Super-Programming Model (SPM), is created. Programs are developed assuming an instruction set architecture comprised of SuperInstructions (SIs). SPM models the target system as a large Virtual Machine (VM); VM contains functional units which are underlain with sub-computer systems and SIs …

Order Scheduling In Dedicated And Flexible Machine Environments, Haibing Li

Dissertations

Order scheduling models are relatively new in the field of scheduling. Consider a facility with m parallel machines that can process k different products (job types). Each machine can process a given subset of different product types. There are n orders from n different clients. Each order requests specific quantities of the various different products that can be produced concurrently on their given subsets of machines; it may have a release date, a weight and a due date. Preemptions may be allowed. An order can not be shipped until the processing of all the products for the order has been …

Utility Of Remote Sensing Data In Retrieval Of Water Quality Consituents Concentrations In Coastal Water Of New Jersey, Ting Yu

Dissertations

Three important optical properties used for monitoring coastal water quality are the concentrations of chlorophyll (CHL), color dissolved organic matter (CDOM) and total suspended materials (TSM). Ocean color remote sensing, a technique to collect color data by detection of upward radiance from a distance (Bukata et al.,1995), provides a synoptic view for determining these concentrations from upwelling radiances. In the open ocean (Case-I), it is not difficult to derive empirical algorithms relating the received radiances to surface concentrations of water quality parameters. In coastal waters (Case-Il), there are serious unresolved problems in extracting chlorophyll concentration because of high concentration of …

Tcp Performance Enhancement In Wireless Networks Via Adaptive Congestion Control And Active Queue Management, Kai Xu

Dissertations

The transmission control protocol (TCP) exhibits poor performance when used in error-prone wireless networks. Remedy to this problem has been an active research area. However, a widely accepted and adopted solution is yet to emerge. Difficulties of an acceptable solution lie in the areas of compatibility, scalability, computational complexity and the involvement of intermediate routers and switches.

This dissertation rexriews the current start-of-the-art solutions to TCP performance enhancement, and pursues an end-to-end solution framework to the problem. The most noticeable cause of the performance degradation of TCP in wireless networks is the higher packet loss rate as compared to that …

How School Counselors Gain Support To Implement Comprehensive Guidance And Counseling Programs, Jo Ann Grant Edd

Dissertations

The school counseling field is evolving from a focus on ancillary activities to a commitment to comprehensive guidance and counseling programs. Understanding strategies school counselors have used in gaining support from key stakeholders to implement comprehensive guidance and counseling programs can be a valuable addition to the literature of school counseling. The present study investigated how elementary and secondary school counselors gained support when implementing comprehensive guidance and counseling programs based on the National Standards for School Counseling Programs. A qualitative methodology was used in the study. The findings revealed that: (a) counselors studied believed their role in gaining support …

An Examination Of The Media's Framing Of The Illegal Street Racing Issue, Kevin Andrew Igasaki Edd

Dissertations

For the last sixty years, the legal community and public policymakers have assumed that illegal street racing has appealed to a single portion of the driving population—young adults driving modified vehicles. However, this assumption has been based solely on anecdotal information and has never been empirically investigated in the literature. To remedy this situation, this mixed methodology study examined whether this narrow framing of the illegal street racing issue was present in two southern California newspapers and two nationally circulated magazines over a three-year time period. Specifically, this study examined the way in which this issue was framed in daily …

The Courage To Change: Striving For Magnet Hospital Recognition, Janet M. Jones Edd

Dissertations

In the ever-changing environment of health care, good leaders are of utmost importance to the effective functioning of the hospital. Leadership in the hospital setting requires innovativeness and courage. This means the passion to discover, create and experience the unknown. Until recently why some hospitals attract and retain good nurses while others do not was unknown. The magnet hospital concept identified attributes that supported the professional practice of nursing which, in turn increased nurse recruitment and retention. The objective of this study was to compare Chief Nursing Officer (CNO) and Chief Executive Officer (CEO) perceptions of their innovativeness and leadership …

Facing The Leadership Challenges On Decommissioning United States Navy Ships, Darren J. Mcglynn Edd

Dissertations

Since the late 1980s, hundreds of U.S. Navy ships have been decommissioned. Although ship decommissionings were postponed immediately after the September 11th attack, today the Navy is again engaged in “rightsizing” its force. Depending on the type of ship and its age, a ship faces different fates after the decommissioning process has been completed. Except on the rare occasion when a ship is turned into a museum, most decommissioned ships are disposed of in one of three ways. Some ships are sold to foreign navies to recoup some costs. Other ships are reassigned to the Military Sealift Command (MSC) to …

Global Citizenship As A Function Of Higher Education: The Demographic And Institutional Determinants In A Graduate Student Population, Jade G. Winn Edd

Dissertations

Over the last twenty years, the explosive growth in information technologies, combined with the globalization and easy access to other cultures, has allowed people to think of themselves more as citizens of the world than of a particular nation. Although the notion of “global citizenship” is often discussed in the popular press, little scholarly attention has been devoted to its measurement. Less attention has been paid to the role higher education plays in creating global citizens. To address these problems, a survey instrument was created to measure three facets of global citizenship: environmentalism, social justice, and civic responsibility, and was …

Culture And Motivation In Online Learning Environments, Frances A. Clem Edd

Dissertations

In the past, instructional design of online learning has largely ignored culture in the creation of online learning environments. Because research in the interaction of culture and online learning is very sparse, an exploratory, blended study was conducted to assess whether there is evidence that one measurable aspect of learners’ culture interacts with the online learning environment in ways that can be observed and identified, and whether this interaction impacts learners’ motivation and behavior in those environments. “Culture” is a complex concept consisting of many interrelated behaviors and values. For this reason, the study focused on one single aspect of …

From Presence To “E-Presence” In Online Nursing Education, Lisa M. Kaiser Phd, Msn, Bsn, Rn

Dissertations

Online web-based course offerings are now common in many institutions of higher education In response to the current and severe nursing shortage, estimated to represent a 20% vacancy rate by the year 2015, (Tarkin, 2003) many more universities have created online nursing courses for registered nurses wishing to continue their education in nursing. The National League for Nursing (NLN) set research priorities that urged exploration of the impact that technology has on the content and nature of teaching and learning in nursing education (1999). Using a series of separate synchronous, online focus groups and 1:1 interviews with nurse educator experts …

Cognitive Orthotics For Students With Cognitive Disabilities, James V. Yanna

Dissertations

This study examined the effectiveness of a hand-held computer to guide an individual with a moderate cognitive impairment as he or she completed a complex daily living task. Performance was compared with that occasioned by a human supervisor. A third condition, assistance first from a human supervisor, and then by the computerized orthotic, was also evaluated. The task selected was a baking task.

Subjects were nine students, ranging in age from 17 to 24 years. All subjects were classified as cognitively impaired according to the Michigan Special Education Rules and Regulations. Assessment information showed most to be performing at a …

School Counselors' Perceptions About Female Participation In Non-Traditional Secondary Career And Technical Education (Cte) Programs, Rashida Khatoon Malik

Dissertations

The purpose of this study was to examine high school counselors' perceptions of female participation in nontraditional secondary Career and Technical Education (CTE) programs. The data for this study was collected from high school counselors in Michigan by sending them a survey containing 25 items. The first section of the survey covered the demographics of the participants. The second section consisted of eight belief statements about counseling femalestudents into nontraditional CTE programs. The third section of the survey had 12 belief statements about female participation in CTE nontraditional programs. The survey responses were based on five-point Likert scales. The belief …

Understanding Photosynthesis And Plant Cellular Respiration As “Nested Systems”: The Characterization Of Pre-Service Teachers’ Conceptions, Mary H. Brown

Dissertations

This dissertation project focused on pre-service elementary teachers' conceptions of the plant processes of photosynthesis and cellular respiration as being connected, occurring at multiple ecological levels, and working within "nested systems." Participants enrolled in a biology course designed for elementary education majors provided their views of the processes through a series of tasks with a peer, a semi-structured interview, and clarified both photosynthesisand plant cellular respiration directly following classroom instruction on the two topics. The instructor of the course was interviewed after a preliminary analysis of the participants' responses. Data were analyzed using the qualitative analysis computer program The Ethnograph …

The Three-Contingency Model Of Self-Management, Holly C. Harrison

Dissertations

The goal of this dissertation is to evaluate people's needs for self-management and the effectiveness of their use of the three-contingency model of self-management. This model prescribes a set of self-management procedures that can be applied to self-manage virtually any behavior. College students used these procedures to manage their own behavior as part of an extended psychology-course assignment.

This evaluation began with the Procrastination Survey, the results of which assessed the frequency of the students' self-management problems. The self-management interventions of up to 168 students were then evaluated using their self-reported performance data and an anonymous survey. The performance data …

Examining The Keyword Mnemonic Strategy As An Effective Academic Intervention For High School Students Labeled Emotional Or Behavioral Disordered, Karen A. Kleinheksel

Dissertations

This investigation explored whether keyword mnemonic strategies were effective for high school aged students labeled emotional or behavioral disordered(E/BD) in recalling the definitions of scientific vocabulary terms. Ten students labeled E/BD from a suburban public high school in a Midwestern state participated in this investigation. A demographic description of the subjects indicated the following information: (a) all students' ethnicities were Caucasian, (b) sixty percent of the subjects were male, (c) the average subject's age was 17 years 1 month, and (d) all students were in the tenth through twelfth grades.

In a multiple baseline across subjects design using a single …

Factors Affecting Treatment Program Development In A Mental Health Facility Serving Prisoners, Ruby Miranda Meriweather

Dissertations

There is a paucity of literature on how treatment programs for mentally ill prisoners are developed. Federal mandates require that services to mentally ill prisoners be comparable to what is offered in the community. Planners, therefore, must find ways to provide treatment programs that produce that outcome.

This research identified the most important factors that affect treatment program development and implementation to aid planners in designing treatment programs for mentally ill prisoners. This qualitative study, based on grounded theory, used a structured interview with 61 mental health staff (psychiatrists, nurses, psychologists, social workers, and activity therapists) across three categories (Administrative, …

Changes In Glial Cell Line Derived Neurotrophic Factor And Nerve Growth Factor Expression With Development, Age, Exercise And Hypertension, Bertha C. Rebimbas-Cohen

Dissertations

Neurotrophic factors are important for neuronal growth, survival, and maintenance of cell phenotype. Glial cell line-derived neurotrophic factor (GDNF) affects sensory, autonomic and somatic motor neurons and nerve growth factor (NGF) affects sensory and sympathetic neurons. NGF and GDNF are produced by cardiac muscle and have potent effects on sensory and autonomic neuronal innervation of blood vessels. Neural innervation plays a key role in blood vessel function. Since neural innervation of blood vessels may be regulated by growth factors, we wanted to determine what changes would occur to NGF and GDNF levels with maturity, exercise and hypertension.

Changes in GDNF …

The Italian Homiliary: Texts And Contexts, Michael Thomas Martin

Dissertations

For the Carolingians, preaching was the best manner in which to teach good, Christian behavior orally to the largely illiterate masses. Studying early medieval sermon collections then can provide historians with a great amount of information on, for example, the intended audience and current moral instruction, who wrote the sermons, and the intended impact of the reform requirements. Too often however these early collections are grouped into a rather generalized classification of being little more than an exposition of Scripture composed with little or no originality. Some scholars claim we have no evidence for sermons produced for popular preaching prior …

Meaningful Learning: Reconciling The Tensions Between Constructivist And Environmentally Sustainable Pedagogy, Nancy Van Kannel-Ray

Dissertations

Critics of constructivism argue, in many ways correctly, that this approach to education is culturally and environmentally damaging because constructivism may not develop an understanding of the interdependence between the human community and the world in which people live. Advocates for environmentally sustainable pedagogy argue the importance of understanding patterns of thinking that allow communities to live sustainably. The purpose of this study is to resolve the tensions between the two pedagogical frameworks: constructivism and environmental sustainability.

The tensions are resolved in two ways. First, there are forms of constructivism that align in viable ways with the criteria critics argue …

Reconciling Temporalities: A Substantive Explanation Of The Origins Of Difficulty In The Nurse Patient Encounter, Marilyn Theresa Macdonald Phd

Dissertations

Nurses describe patients as difficult on a regular basis. Nursing research to date has assumed the existence of this phenomenon. Most studies have listed descriptors of the difficult patient and offered interventions for nurses to use to alter patient behavior. Locating of difficulty within the individual and failure to consider the context of the nurse patient encounter is problematic. The practice of locating difficulty in the individual absolves organizations and society of responsibility to work to change factors that contribute to the construction of difficulty. The purpose of this research was to move beyond a focus on the patient as …

Hope—Heartbeat Of Adult Education: A Phenomenological Inquiry, Phillip L. Moulden

Dissertations

This phenomenological study of the phenomenon—hope identified two essential meaning structures (“change” and “human agency”) in the experiences communicated by the Adult Educators interviewed. It was also discovered that hope is an energy that interacts with Affective, Relative (Re-lay-tive), and Cognitive energies in the lives of the research participants. Understanding how “change” and “human agency” can be aligned with these A.R.C. energies holds implications for further research and the practice of Adult Education.