Profile analysis techniques for observation-based software testing

Leon Cesin, David Zaen Case Western Reserve University 2005 해외박사(DDOD)

Observation-based testing is a software-testing paradigm based on the idea of observing the behavior of the program when executed under a variety of test cases. The runtime behavior of a program can be summarized in profiles, which can then be analyzed for a variety of purposes useful for the tester. This dissertation presents techniques for test suite visualization, test case selection and test case prioritization based on profile data and includes extensive experiments on large, real-world applications to compare these techniques with ones from the literature. Test suite visualization is the application of multivariate visualization techniques to profile data in order to visually study the composition of the test suite and its interaction with the program. Two techniques are examined for this purpose, Correspondence Analysis and Multidimensional Scaling, and a novel algorithm for the latter is presented and studied. Example applications of test suite visualization are provided. Test case selection is the problem of selecting a small set of tests from a large test suite such that the most defects are revealed when this subset is executed. Test case prioritization is the problem of finding an optimal scheduling of the tests in a test suite so that the number of defects found earlier during testing is maximized. Other researchers have tried to address these problems using profile information, by looking at the amount of code executed by a subset of tests. Dickinson proposed some methods for test-case selection that consider the distribution of the profiles in the profile space by using cluster analysis on the profiles. This work was later extended in conjunction with the author. These methods will be presented in this work, together with novel methods for test case prioritization. Experimental validations and comparisons of all of these methods will be presented, including comparison criteria that were missing from earlier work. The results suggest that profile analysis is a useful tool for software testers, and that studying the distribution of tests in a profile space can be more beneficial than concentrating on code coverage.

Mechanical ventilation antioxidant trial

Howe, Kimberly Palazzo Case Western Reserve University 2005 해외박사(DDOD)

There is growing concern among critical care professionals and the public about the growing number of critically ill patients requiring mechanical ventilatory support (MVS). The suffering these patients endure is enormous. They experience pain and discomfort caused by the artificial airway, frustration with communicating their needs and helplessness at the loss of control of their lives. These patients consume a disproportionate amount of financial and personal resources burdening both families and hospitals. Past research has focused on the use of point-in-time respiratory and ventilatory measures to predict patients' success of breathing spontaneously. There is growing evidence that systemic inflammation may play a role in dependence on MVS. The purpose of this study was to test the clinical effectiveness of antioxidant supplementation in reducing the duration of MVS using a randomized, double-blind, placebo-controlled clinical trial. Seventy-two critically ill adults, requiring MVS for at least 72 hours were recruited from the MICU and SICU of a 450-bed, university-affiliated community teaching hospital. Subjects were randomly assigned receive either (1) placebo, (2) 1000mg vitamin C + 1000 IU vitamin E, or (3) 1000mg vitamin C + 1000 IU vitamin E + 400mg N-acetylcysteine (NAC) administered enterally every 8 hours. The mean duration of MVS for subjects receiving vitamins C and E was a mean of 10 days (median of 6 days) and for those receiving vitamins C and E plus NAC was a mean of 12 days (median of 6 days). The mean duration of MVS for those subjects receiving placebo was a mean of 19 days (median of 15 days). Clinical and statistical differences (Mantel-Cox log rank statistic = 5.69, df = 1, p = .017) were found in the duration of MVS between those in the placebo group and those in the two treatment groups. There were no differences in duration of MVS between the two antioxidant supplement groups. Enteral antioxidants are a simple, safe, inexpensive and effective intervention to decrease the duration of MVS in critically ill adults. NAC does not appear to offer any additional benefit in those receiving vitamins C and E.

Haplotype-based approaches to genetic case-control studies

Fallin, Margaret Daniele Case Western Reserve University (Health Sciences) 2001 해외박사(DDOD)

Haplotype-based methods for disease-gene identification may have considerable advantage over single-locus tests due to their ability to identify unique chromosomal segments that harbor disease variants. Further, recent developments in single nucleotide polymorphism (SNP) technology have contributed to the feasibility of large-scale case-control association analyses as tools for disease gene discovery. However, for haplotype-based methods to be employed for un-related case-control individuals, phase information must be available. This dissertation combines a method of haplotype frequency estimation from multiple SNP genotypes using the E-M algorithm, with several statistical methods aimed at comparing frequencies of haplotypes between case and control groups. The accuracy of the haplotype estimation procedure has been examined in detail under several different population parameters. E-M haplotype frequency estimation is shown to be very accurate over a wide variety of situations, and the importance of sampling error is emphasized. The statistical comparisons using haplotype frequency estimates emphasize the need for ‘omnibus’ testing procedures that compare overall frequency differences between groups rather than concentrating on any particular haplotype. Further, given the likelihood of sparse data when considering observed haplotypes, a random permutation approach to the assessment of empirical p values is employed. The power of omnibus test several different alternative situations. Finally, the utility of methods presented is demonstrated in a case-control sample of Alzheimer's disease patients and non-demented controls. The results show the ability of the haplotype-based methods to detect the well-known association between Alzheimer's disease and the APOE gene on chromosome 19, in a more compelling way than single-locus tests.

Surface diffusivity measurements on 8mol.% yttrium oxide-zirconia bicrystals via grain boundary grooving experiments

Nassirou, Maissarath Case Western Reserve University 2005 해외박사(DDOD)

Thermal grooving at grain boundaries (GBs) is a capillary-driven evolution of surface topography in the region where the grain boundary emerges at a free surface. The study of these topographic changes can provide insight into surface energetics, and in our particular case, the measurement of surface diffusivity. We have measured the surface diffusion coefficient of 8mol% Y 2O3-ZrO2 by studying the formation of thermal grooves. We studied a total of five bicrystals, with well defined orientation relationships; random [110] -60°, random [001] -30°, Sigma13 [001]/{510}, Sigma13 [001]/{320}, Sigma5 [001]/{210}. Our calculations employed the Herring relation (1951), in which the variation in the chemical potential is related to changes in topography. The samples were annealed at 1300°C and 1400°C for various period of time. Atomic Force Microscopy was used to determine the exact geometry of the thermal grooves. A first approach consisted of estimating the diffusion coefficient by using Mullins' equation. yx=0= dsDs1/ 4gb2g s12G 5/4&parl0; WkTgs&parr0; 1/4t 1/4 Where y(x =0) is the groove depth at the GB triple junction, O is the atomic volume, gs is the surface tension, gb is the grain boundary surface energy, ds is the thickness of the diffusion layer, t is the annealing time, and Ds is the surface diffusion coefficient. In Mullins' derivation, the atomic structure of the surface was ignored and it was assumed that the surface energy is independent of crystallographic orientation. In the case of zirconia, the surface energy is anisotropic. We will describe in this work a new approach to measuring surface diffusivity which accounts for the surface energy anisotropy. The study of these bicrystals will emphasize the effect of grain boundary structure on the surface diffusion coefficient, and it is for that purpose that we selected bicrystals with different tilt axes and angles. The results obtained using the equation set we have developed will be compared to those obtained by Mullins, and we show that the anisotropic groove evolution, even when perfectly symmetrical, is much slower than the corresponding isotropic case.

Factors associated with moderate and severe postoperative pain

Kless, Jack R Case Western Reserve University 2010 해외박사(DDOD)

Postoperative pain continues to be a serious consequence of surgical intervention. Understanding the predictive factors of postoperative pain would allow nurses to identify those at increased risk and to better direct resources to ameliorate significantly high levels of postoperative pain. Based on the theory of unpleasant symptoms, the purpose of this research was to identify the factors correlated with moderate and severe postoperative pain. Using a predictive correlational design, this study was a secondary analysis of a randomized controlled trial of nonpharmacological interventions for the treatment of postoperative pain (Good et al., 1999). The sample consisted of 292 participants from the primary study who had pain scores on the first day after major abdominal surgery. Two levels of moderate to severe pain, moderate30 (30 to 100 mm) and moderate50 (50 to 100 mm), and one level of severe postoperative pain (70 to 100 mm) were studied. Logistic regression was used to examine the relationship of eight independent variables on on moderate and severe postoperative pain: gender, age, chronic preoperative pain, acute preoperative pain, physical status, surgical procedure, length of surgery, and length of incision. The model accounted for 10% of the variance at moderate30 postoperative pain and predicted 70% of the cases. At moderate50 postoperative pain only 6% of variance was explained and 60% of cases were correctly classified. At severe70 postoperative pain, 12% of variance was explained, and 79% of cases were correctly classified. Age and ASA physical status were significant predictors at all three levels of postoperative pain. The model was more accurate at moderate30 and severe70 postoperative pain, but explained variance was low, and -2 log likelihoods were relatively high. The theory of unpleasant symptoms was partially supported by finding that age and ASA physical status were predictive of postoperative pain levels and the major implication for nursing is to increase nurses' effort to uncover untreated postoperative pain, and to better direct resources to ameliorate it.

A cockroach inspired robot with artificial muscles

Kingsley, Daniel A Case Western Reserve University 2005 해외박사(DDOD)

A robot was developed for the purpose of research into legged locomotion. Legged robots are complex mechanisms, and their development can be greatly aided by insights into the mechanisms---both physical and control---by which animals locomote. This text presents the design methodology used for the development of the fifth such biologically inspired robot at Case: Robot V. The robot is based on the deathhead cockroach, Blaberus discoidalis. It has twenty-four degrees of freedom (DOF) distributed amongst task oriented legs; five DOF in the front legs, four DOF in the middle, and three DOF in the rear. Previous research has shown that this joint configuration can closely approximate that of the cockroach, while not being too complex from an engineering standpoint. Actuation is by braided pneumatic actuators, and coupled with a valve system that allows air to be trapped within the actuators, numerous beneficial muscle-like properties were produced. Most importantly, this system enabled rapid response to perturbation, much like "preflexes" exhibited by animals, affording the system a level of passive stability. The robot is controlled by a hierarchical control system, and the operation of the interleg coordination mechanism, a variant of the distributed network of the responsible for stick insect interleg coordination proposed by Cruse, is discussed in detail. The robot has demonstrated open loop passive stability and locomotion. With the addition of joint angle and actuator pressure sensors, the robot has been able to perform "air walking" motions while suspended from a gantry as well as walking on a treadmill while its weight is partially supported. Closed loop walking has been accomplished, but further development of its locomotion controllers is called for.

Formal concepts and applications

Shen, Gongqin Case Western Reserve University 2005 해외박사(DDOD)

Formal Concept Analysis (FCA) is a powerful tool for symbolic data analysis using a mathematical structure called lattice. FCA has novel applications in areas such as data mining and information retrieval. In this thesis, we study the theory and applications of FCA. This thesis consists of three parts. The first part introduces a new notion of formal concept, called approximable concept, and connect this notion to semantic domain theory. FCA has been traditionally focused on finite contexts and finite concept lattices, therefore neglecting the full power of the theory. After a thorough investigation, we developed a new definition of concept, inspired by the ideas of partial information and successive approximation in domain theory, to provide computationally meaningful alternative. Domain theory is a branch of order theory invented by Scott for the denotational semantics of programming languages. The theoretical contribution of this part amounts to a systematic connection, in the form of a categorical equivalence, between formal concept analysis and domain theory. The second part presents a tool for automatic concept lattice layout and visualization. Concept lattices are normally represented by a list of string pairs instead of a lattice diagram. Currently, there are no standard rules for the visualization of concept lattices. We develop a tool which creates balanced and well-built lattice diagrams for finite contexts, automatically. The diagram layout of concept lattices help us understand the whole structure of concept lattices. The third part shows a method for web-menu layout design and describes a user evaluation study comparing the resulting menu layout of an existing real world web site with the one derived from our method. Most of today's web sites' menu layouts are created by the intuition of the web designers. We propose a new FCA-based semi-automatic web-menu design methodology, called FcAWN (Formal Concept Analysis for Web Navigation), to construct more consistent and reasonable layouts of web sites. In FcAWN, hyper-link hierarchies are considered as part of a lattice structure instead of a tree structure. We apply our method to Case University's EECS departmental web site to obtain a new design and implementation. A user evaluation study was conducted to compare the differences between the original site and the new one generated by FcAWN. By restricting to the data on users giving up answering questions of our carefully designed questionnaire, the FcAWN site has already shown a statistically significant advantage over the existing one in terms of usability.

The making of bioethical history

Lauritzen, Lydia Case Western Reserve University 2010 해외박사(DDOD)

This research is a diachronic case study of a series of sentinel ethical events at a medical research facility as represented in the media, in courtroom dialogue and in academic journals. Between 1981 and 1993, physicians at Fred Hutchinson Cancer Research Center (FHCRC) placed 85 criteria-eligible patients into sequential versions of a research protocol designed to improve their bone marrow transplant survival. 83 of these 85 patients are known to have died. The other two charts have not been located. In 2001, one of those research physicians worked with an investigative journalist to tell his experience with the protocol to the surviving families, to the public and eventually to the courts. These events offer a rich ground for exploring the enduring moral problems of contemporary research medicine and the formulation of Bioethical history. My research provides a critical cultural analysis of the events surrounding the FHCRC's retrospectively contested protocol and the narrative formulation of an ethical case. I draw predominantly on court transcripts and the triangulated dialogue between FHCRC, the media and academic journals to explore how the particular ethical issues were framed, presented, contested and finally collapsed into an official account. My premise is that narrative is a key constructive -- deconstructive process in Bioethics. It negotiates the 'real story' and determines what counts as history. My second point is that the shape of ethical debates and how they resolve are important artifacts of the cultural moment. Both things inflect the direction of academic and clinical Bioethics. I interpret my findings from a cultural constructivist perspective to show how text, narrative and courtroom performance are active iterations of contemporary cultural themes, and how the resolution of key ethical events in medical research contribute to the evolution and to the historiography of Bioethics. Importantly, the analytic perspective brought to bear on this study moves past a Cartesian tethering to right or wrong. It challenges the reader to deconstruct the default master narratives in ethical debates. It offers a lens through which to imagine new approaches to the recurrent ethical problems arising within investigational medicine.

Effects of free surface heat transfer and shape on thermocapillary flow of high Prandtl number fluids

Wang, Aihua Case Western Reserve University 2005 해외박사(DDOD)

The main objective of the present work is to study the effect of free surface heat transfer on the thermocapillary flow of high Prandtl number fluids. The effect of free surface heat transfer is investigated experimentally and numerically in the liquid bridge configuration. A numerical code basing on the finite volume method is used to simulate the steady liquid flow and airflow. The air motion is simulated in order to compute the free surface heat transfer rates for given experimental conditions. The numerical analysis in liquid bridges shows different flow structures between heat gain and loss cases. The relationships between the onset of oscillatory thermocapillary flows and free surface heat transfer in the bridge geometry are identified. The free surface heat transfer has a significant effect on the onset of oscillatory flow in liquid bridges with a nearly cylindrical surface. The critical temperature difference, or the critical Marangoni number, is very sensitive to the heat loss from the free surface. The dynamic free surface deformation in the hot corner is very important and responsible for the observed heat loss effect. Namely the S-parameter correlates with the critical conditions well under the heat loss conditions. The heat transfer from the free surface has no effect on liquid bridges with a highly concave free surface. The critical Marangoni number remains constant and also predicts the onset of oscillations well for liquid bridges with a nearly cylindrical free surface under net heat gain conditions and liquid bridges with a highly concave free surface under heat gain/loss conditions. Two different physical mechanisms of transition from steady thermocapillary flow to oscillatory thermocapillary flow in liquid bridges of high Prandtl number fluids are responsible for the observed oscillation phenomena. One is the interaction between the surface heat loss and dynamic free surface deformation in the hot corner for liquid bridges with a nearly cylindrical free surface. The other is the azimuthal propagation of hydrothermal waves without surface deformation for liquid bridges with a nearly cylindrical free surface under heat gain conditions and liquid bridges with a highly concave free surface.

Antiviral and antitumor functions of RNase L

Li, Geqiang Case Western Reserve University 2005 해외박사(DDOD)

RNase L is an endoribonuclease that functions in the molecular pathways of interferon (IFN) action against viral infections. Although the pro-apoptotic activity of RNase L is well known, how RNase L activation during viral infection leads to apoptosis is not clear. Recently, RNase L was considered to be a tumor suppressor based on its pro-apoptotic activity and mapping to hereditary prostate cancer allele 1 (HPC1). While involvement of a viral pathogen in prostate cancer was proposed (Silverman 2003), the unknown novel mechanism of RNase L in the suppression of prostate cancer progression still remains possible. Several lines of evidence implied that RNase L may possess an unidentified function: first, RNase L+/+ fibroblasts are different from RNase L-/- in morphology. Second, RNase L -/- mice showed a 5-day delayed rejection of skin allograft and a dramatic reduction in inflammatory infiltrates (Silverman RH et al 2002), indicating that RNase L play a role in immunosystem. Third, RNase L was found to interact with actin cytoskeleton (Tnani M et al 1998), and the interactions were abolished by PMA treatment of the cells. Finally, three inactivating mutations (M1I, E265X, and Delta157) and an additional nine missense variants (G59S, I97L, I220V, V247M, G296V, and S322F) in RNase L have been observed in prostate cancer cases. No mutation is mapped in the ribonuclease domain, indicating that ribonuclease domain might not be involved in RNtase L related pathogenesis in prostate cancer. My thesis thus focused the possible mechanisms of the antiviral and antitumor functions of RNase L. In antiviral studies, my thesis showed that 2--5A, dsRNA and viral infection induced activation of the c-Jun NH2-terminal kinases (JNK) family of MAP kinases and viral induction of apoptosis are deficient in mouse cells lacking RNase L. In addition, 2--5A resulted in specific ribosomal RNA cleavage products coinciding with JNK activation. Moreover, 2--5A induced apoptosis was dramatically enhanced by IFN pretreatment in JNK1+/+ JNK2+/+ cells but not in Jnk1-/- Jnk2-/- cells. These findings suggest that JNK and RNase L function in an integrated signaling pathway during the IFN response that leads to elimination of virus-infected cells through apoptosis. In antitumor studies, my research established that haptotaxis of RNase L-/- MEF cells increased about two fold, compared to their wildtype counterparts. (Abstract shortened by UMI.).