The field of software engineering embraces measurement, analysis and modeling of software. Software metrics are often based on counting, whereas this thesis adopts information theory. The goal of this research is to show that information theory-based metrics proposed by Allen can be useful for software development projects compared to counting-based metrics. Briand, et.al. have defined five families of measures based on counting the elements of a graph. This research considers a hypergraph system. Parallel Mathematical Library Project (PMLP) was used as the case study. Abstract semantic graphs were generated for the C++ source files of PMLP in the form of nodes * hyperedges tables, which are measured for counting and information theory-based measures. Analysis showed that information theory-based metrics provide fine-grained distinctions among the modules, compared to the counting-based metrics. The case study measurements conformed to the properties proposed by Briand et.al. as well.

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Introduction: Wearable technologies play an important contemporary role in the measurement of physical activity (PA) and promotion of human health across the lifespan, including for young people (i.e., children, adolescents, and young adults). As new objective wearable technologies continue to develop, standardized approaches to documenting validation parameters (i.e., measures of accuracy, precision, and bias) are needed to ensure confidence and comparability in step-defined PA. Purpose: To produce validity parameters for step counting wearable technologies during treadmill walking in young people 6-20 years of age Methods: 120 participants completed 5-minute treadmill bouts from13.4 to 134.1 m·min-1. Participants wore eight technologies (two at the arm/wrist, four at the waist, one on the thigh, and one on the ankle) while steps were directly observed. Speed, wear location, and age -specific measures of accuracy (mean absolute percent error; MAPE), precision (correlation coefficient, standard deviation; SD, coefficient of variation; CoV), and bias (percent error; PE) were computed and cataloged. Results: Speed and wear location had a significant effect on accuracy and bias measures for wearable technologies (pConclusion: While the analyses indicate the significance of speed and wear location on wearable technology performance, the useful and comprehensive validity reference values cataloged herein will help optimize measurement of PA in youth. Future research should continue to rigorously validate new wearable technologies as they are developed, and also extend these standardized reference values developed in the laboratory to the free-living environment.

Learning the count list (one, two, three, …) is a critical stepping-stone for the acquisition of number concepts. Most research about counting, however, is done in the behavioral domain, and little is known about the neural representations underlying counting sequences. Here, we test the hypothesis that transitional knowledge within a counting sequence exist both at sensory and conceptual (ordinal and magnitude) levels. To test this hypothesis, we employed a passive-listening violation-to-expectation fMRI paradigm where adult participants heard auditory count sequences that were correct (4 5 6 7) or violated at the end (4 5 6 8; consecutiveness) and, orthogonally, that were ordered or unordered (orderedness). Another orthogonal dimension was the manipulation of sensory sequence violation where the voice speaking the numbers was consistent throughout the trial or could change on the last number (voice identity). This 2x2x2 factorial design was analyzed using univariate and multivariate pattern analyses. Three clusters in the right fronto-parietal network (BA44, BA46, and IPS) showed greater neural response to violations to orderedness. Of the three clusters, the anterior IFG (BA46) demonstrated the encoding of consecutiveness. Interestingly, the bilateral STG, which showed a robust effect to violations in voice identity, also demonstrated the encoding of consecutiveness. These results indicate that a right-lateralized fronto-parietal network activity can differentiate between a count list and random numbers, while BA46 and bilateral STG respond specifically to violations of the count sequence, suggesting specific mechanisms in the brain for processing consecutive numbers in both the perceptual and cognitive levels.

Subitizing, a quick apprehension of the numerosity of a small set of items, is inconsistently utilized by preschool educators to support early number understandings (Sarama & Clements, 2009). The purpose of this qualitative study is to investigate the relationship between children’s number understanding and subitizing activity. Sarama and Clements (2009) consider students’ subitizing activity as shifting from reliance upon perceptual processes to conceptual processes. Hypothesized mental actions carried into subitizing activity by children have not yet been empirically investigated (Sarama & Clements, 2009). Drawing upon Piaget’s (1968/1970) three mother structures of mathematical thinking, the theoretical implications of this study consider expanding the scope of Piaget’s (1968/1970) definition of topological thinking structures to include patterned orientations. Increasing the scope of this definition would allow for the investigation of the development of topological thinking structures and subitizing activity. An 11-week teaching experiment was conducted with six preschool aged children in order to analyze student engagement with subitizing tasks (Steffe & Ulrich, in press). To infer what perceptual and conceptual processes students relied upon when subitizing, tasks were designed to either assess or provoke cognitive changes. Analysis of interactions between students and the teacher-researcher informed this teacher-researcher of cognitive changes relative to each student’s thinking structure. Results indicated that students rely upon the space between items, symmetrical aspects of items, and color of items when perceptually subitizing. Seven different types of subitizing activity were documented and used to more explicitly describe student reliance upon perceptual or conceptual processes. Conceptual subitizing activity was redefined in this study, as depending upon mental reversibility and sophisticated number schemes. Students capable of conceptual subitizing were also able to conserve number. Students capable of conserving number were not always capable of conceptual subitizing. The symmetrical aspects of an item’s arrangement elicited students’ attention towards subgroups and transitioning students’ perceptual subitizing to conceptual subitizing. Combinations of counting and subitizing activity explained students’ reliance upon serial and classification thinking structures when transitioning from perceptual subitizing to conceptual subitizing. Implications of this study suggest effectively designed subitizing activity can both assess students’ number understandings, and appropriately differentiate preschool curriculum. / Ph. D.

Fiber-optic Bragg grating (FBG) sensors are a very attractive technology for the measurement of strain and temperature. They have many advantages over conventional sensors in sensing applications such as sensitivity, immunity to electromagnetic interferences,large bandwidths,capability of remote operation and the potential power to sense micro strain at high temperature. They can be directly embedded into many structures such as concrete to evaluate the material deformation. FBGs are fabricated by photo-inscribing through a phase mask technology on a photosensitive fiber. A periodic refractive index is formed in the fiber core, introducing a reflection at the Bragg wavelength. Since the FBG is characterized by a low insertion loss and controllable reflectance, it has the potential to be multiplexed in very large numbers. The major purpose of this dissertation research is to develop an innovative, high- resolution fiber Bragg grating sensing system using photon-counting optical time domain reflectometry (pc-OTDR) based multiplexing technology. The system uses a Fresnel reflection OTDR with a zero deadzone to detect FBG sensors, which improves both the system detection ability and spatial resolution. A low reflectance FBG with broad bandwidth has been developed that is appropriate for the pc-OTDR measurement. Hundred of multiplexed sensors have been implemented in this system. Two theoretical analyses and preliminary results are presented. The greatest advantage of the system is to increase the maximum multiplexing sensor number to one thousand within a short fiber range. Self-referencing demodulation is necessary to eliminate multiplexed system noise caused by the source power fluctuation and fiber bending effects. A referencing FBG with a different wavelength from the sensing FBG has to be introduced to achieve compensation of disturbances in the measurement. The spectral properties of the FBGs and the combination of WDM/TDM are also discussed to evaluate multiplexing sensor performance. The sensor crosstalk and other noise performances are assessed to evaluate the possibility of large scale multiplexing. / Ph. D.

A network (graph) is a powerful abstraction for interactions among entities in a system. Examples include various social, biological, collaboration, citation, and co-purchase networks. Real-world networks are often characterized by an abundance of triangles and the existence of well-structured communities. Thus, counting triangles and detecting communities in networks have become important algorithmic problems in network mining and analysis. In the era of big data, the network data emerged from numerous scientific disciplines are very large. Online social networks such as Twitter and Facebook have millions to billions of users. Such massive networks often do not fit in the main memory of a single machine, and the existing sequential methods might take a prohibitively large runtime. This motivates the need for scalable parallel algorithms for mining and analysis. We design MPI-based distributed-memory parallel algorithms for counting triangles and detecting communities in big networks and present related analysis. The dissertation consists of four parts. In Part I, we devise parallel algorithms for counting and enumerating triangles. The first algorithm employs an overlapping partitioning scheme and novel load-balancing schemes leading to a fast algorithm. We also design a space-efficient algorithm using non-overlapping partitioning and an efficient communication scheme. This space efficiency allows the algorithm to work on even larger networks. We then present our third parallel algorithm based on dynamic load balancing. All these algorithms work on big networks, scale to a large number of processors, and demonstrate very good speedups. An important property, very related to triangles, of many real-world networks is high transitivity, which states that two nodes having common neighbors tend to become neighbors themselves. In Part II, we characterize networks by quantifying the number of common neighbors and demonstrate its relationship to community structure of networks. In Part III, we design parallel algorithms for detecting communities in big networks. We propose efficient load balancing and communication approaches, which lead to fast and scalable algorithms. Finally, in Part IV, we present scalable parallel algorithms for a useful graph preprocessing problem-- converting edge list to adjacency list. We present non-trivial parallelization with efficient HPC-based techniques leading to fast and space-efficient algorithms. / Ph. D.

Platelet rich plasma (PRP) is a popular autologous biological therapy used for the treatment of various equine ailments, including tendon and ligament injuries, osteoarthritis, and cutaneous wounds. A number of commercial products are available for producing PRP, each generating a slightly different product. Variations in platelet numbers and white blood cell (WBC) counts are believed to be the most critical variables, as they are directly related to concentrations of growth factors and inflammatory cytokines. Accurate documentation of platelet numbers is essential for prospective evaluation of clinical outcomes, but can be problematic in platelet concentrates depending on the counting method employed. The objectives of this study were to compare the performance of four platelet counting technologies in equine platelet concentrates and to evaluate the ability of the Magellan PRP system to concentrate equine platelets. We hypothesized that there would be no differences in platelet counts among the four counting technologies and that the Magellan system would generate platelet concentrations greater than 500,000/μL. Citrated whole blood was collected from 32 horses and platelet, WBC, and red blood cell concentrations were measured using a commercial hematology analyzer (Advia 2120) prior to preparation of PRP using the Magellan system. Platelets were quantified in individual identical aliquots of equine PRP produced by the Magellan system (n=32) using three different technologies: optical scatter (Advia 2120), impedance (CellDyn 3700), and hand count using direct microscopy (Thrombo-TIC). An immunofluorescent counting method was performed on a subset of 15 of the 32 samples using a mouse monoclonal anti-sheep antibody against integrin alpha αIIbβ₃ (anti-CD41/CD61) and a fluorescent secondary antibody. Measured platelet concentrations were compared using Passing and Bablok regression analyses and mixed model ANOVA. The Magellan PRP system yielded mean (± SD) platelet and WBC counts of 893,090 ± 226,610/μL and 35,806 ± 9,971/μL, respectively. Platelet counts generated by optical scatter were consistently higher than those generated by impedance. Systematic and proportional biases were observed between these two automated methods. No bias (systematic or proportional) was observed among any of the other counting methods. Despite the bias detected between the two automated systems, there were no significant differences on average among the four counting methods evaluated, based on the ANOVA. All four platelet counting methods tested are therefore suitable for quantifying platelets in equine PRP for clinical applications. The Magellan PRP system consistently generated desirably high platelet concentrations as well as higher than expected WBC concentrations. The high platelet concentrations served as a good test medium for the study; however, the concurrent high WBC counts may be undesirable for selected orthopedic applications. / Master of Science

Dissertation (PhD)--Stellenbosch University, 2000. / ENGLISH ABSTRACT: The use of helicopters has become almost universally accepted as the method of choice in the enumeration of large ungulates in Southern Africa. In most cases decisions affecting management of these populations are made based on a single count result. In all these instances the within technique variance is ignored, often leading to decisions based on type I or type II statistical errors where the within technique variance is misconstrued as the population change. Many studies have investigated the issue of accuracy of counting methods and a few have quoted precision values for various methods. Very few have, however, investigated power and those extant have approached the problem from a prospective point of view and predicted power values. This study has made use of replicated counts from 12 sites of the original 23 in four vegetation types of the then Transvaal Province. The study sites vary in terms of size and all counts were undertaken with an experienced, trained team in which only four observers were used. A comprehensive post hoc analysis of the results of the field surveys shows precision and power to vary widely according to species and vegetation type and concludes that gamecounting results are largely site specific. A decline in observations during the course of four hours of survey is demonstrated and although the exact cause cannot be determined, correction factors have been constructed for two vegetation types. Observers are shown to differ from one another in observation profile during the course of surveys. This study demonstrates, describes and quantifies the existence of several phenomena suspected to exist by experienced game counters, biologists and wildlife managers and makes proposals in terms of improving the data returned from expensive aerial surveys. / AFRIKAANSE OPSOMMING: In Suider-Afrika word die gebruik van 'n helikopter vir die tel van hoefdiere byna algemeen aanvaar as die metode wat voorkeur geniet. In meeste gevalle word besluitnemings rakende die bestuur van hierdie populasies gebaseer op die resultate van 'n enkele telling. In al die gevalle word tegniekverwante afwykings buite rekening gelaat en dit het die gevolg dat bestuursbesluite gebaseer word op tipe I en tipe II statistiese foute, en dit lei weer op hulle beurt dat tegniekverwante afwykings verkeerdelik geïnterpreteer word as die rede vir veranderings in die bevolkings. Verskeie studies het al die feitegeskil omtrent die akkuraatheid van telmetodes ondersoek en sommige het herhaalbaarheidswaardes vir die verskillende metodes aangehaal. Baie min het egter statistiese mag ondersoek en die wat dit wel gedoen het, het prospektiewe magsanalise as uitgangspunt gebruik en statistiese magwaardes voorspelom die probleem aan te spreek. Hierdie studie het gebruik gemaak van herhaalde tellings van 12 gebiede uit die oorspronklike 23 in vier veldtipes geleë in die ou Transvaal Provinsie. Die studiegebiede verskil in groottes. Alle tellings is deur 'n bekwaamde opgeleide span gedoen wat slegs vier waarnemers ingesluit het. 'n Omvattende post hoc analise van die resultate van die veldopnames dui aan dat herhaalbaarheid en statistiese mag baie varieer met betrekking tot spesies en veldtipes en word die gevolgtrekking gemaak dat wildtellingsresultate grootliks gebiedsgebonde is. In Afname in waarnemings gedurende die verloop van In vier uuropname, is waargeneem en alhoewel die ware oorsaak nie vasgestel kan word nie, is korreksiefaktore bereken vir twee veldtipes. Dit blyk dat waarnemers van mekaar verskil het met betrekking tot hul waarnemingsprofiele gedurende die verloop van die opnames. Hierdie studie dui aan, beskryf en kwantifiseer die bestaan van verskeie verskynsels wat vermoedelik bestaan het by ervare wildtelIers, bioloë en wildlewebestuurders en maak voorstelle met betrekking tot die verbetering van data wat tydens duur lugopnames ingesamel word.