Agile Business Suite Log Analysis and Stochastic Modeling of Transactions

Agile Business Suite (ABSuite) is an application development and deployment product that can define, generate and manage complete, highly scalable, real world, platform independent applications. The product was developed by Unisys Corporation with the intention to allow developers to rapidly develop their complete applications without having to think about low level platform dependent implementation details thus saving them from having to write thousands of lines of code. Many enterprises like Banks, Healthcare Facilities, Traffic Management, Financial Institutions and etc. use ABSuite to develop their applications and automate their business logic. Once deployed on the application servers, the generated applications are managed by the ABSuite Runtime framework. One important function of the ABSuite Runtime is to maintain a set of log files that contain immense information on system behavior, communication between the system and the runtime framework and user interaction with the system. There are various kinds of log files that are generated by the ABSuite Runtime, each having its own format and vast amounts of hidden knowledge stored in them. These log files contain important information regarding usage patterns, system failure patterns and other performance bottlenecks. Thus proper analysis of these log files is necessary to obtain vital information which will help in optimizing system performance, easing maintenance tasks, identifying hidden bugs and abnormal behavior and adopting better design strategies. Log files are produced by almost all devices, systems and protocols. In general, the analysis of any kind of log file is not an easy task. There are several challenges that need to be addressed first in order to obtain proper and accurate results. The first issue is directly related to the fact that ABSuite log files are often huge and heterogeneous in nature. Standard Algorithms fail in such conditions and thus the task of log analysis requires a different approach. Secondly, identification of required information and the log files storing such information requires domain specific knowledge and expertise regarding the generated log files. Without prior information on what to look for and where to look for, the analysis process will become impossible. Last but not least is the issue of unstandardized format of each of the ABSuite log files which makes processing a difficult task. Keeping the above things in mind, this thesis presents some of the ideas behind developing a tool that automatically analyzes the generated ABSuite log files and extracts information that will help the developers to optimize the application’s performance and reduce the system’s downtime and maintenance cost. vii In this thesis we discuss three stages of analysis. The first stage (Ispec Analysis) finds basic statistical parameters like trigger count, frequency and probability distribution of each transaction occurring in the system. This information is used in subsequent stages to obtain more accurate results and hypothesis. In addition, We also present a way to use the results of this stage to estimate usage and traffic patterns, peak loading conditions and heavily used modules of the system. The second stage (Response Time Analysis) obtains mean time to response for each transaction. This information is used to identify transactions with high latencies and find the most likely cause of those latencies. The third stage (Exception Analysis) finds which transactions frequently generate exceptions and how many types of exceptions are generated by each transaction. The results of this stage help in identifying the number, type, severity and cause of exceptions generated by the system. The results of this stage can also help in taking high level decisions like whether system resources need to be increased to avoid deadlocks, whether there is any need to increase bandwidth allocation, whether there is any need to change the current design of the system and etc. Finally, we present and compare the analysis results of all the three stages for two sample applications (developed using ABSuite) with known usage characteristics. We also explain how the developers can use the results of each stage of analysis to better optimize their systems using the two sample applications as case study

Limit distributions of random walks on stochastic matrices

Problems similar to Ann. Prob. 22 (1994) 424–430 and J. Appl. Prob. 23 (1986) 1019–1024 are considered here. The limit distribution of the sequence XnXn−1 ··· X1, where (Xn)n≥1 is a sequence of i.i.d. 2 × 2 stochastic matrices with each Xn distributed as μ, is identified here in a number of discrete situations. A general method is presented and it covers the cases when the random components Cn and Dn (not necessarily independent), (Cn, Dn) being the first column of Xn, have the same (or different) Bernoulli distributions. Thus (Cn, Dn) is valued in {0, r}2, where r is a positive real number. If for a given positive real r, with 0 \u3c r ≤ 1 2 , r−1Cn and r−1Dn are each Bernoulli with parameters p1 and p2 respectively, 0 \u3c p1, p2 \u3c 1 (which means Cn ∼ p1δ{r} + (1 − p1)δ{0} and Dn ∼ p2δ{r} + (1 − p2)δ{0}), then it is well known that the weak limit λ of the sequence μn exists whose support is contained in the set of all 2 × 2 rank one stochastic matrices. We show that S(λ), the support of λ, consists of the end points of a countable number of disjoint open intervals and we have calculated the λ-measure of each such point. To the best of our knowledge, these results are new

Convergence of nonhomogeneous stochastic chains with countable states

AbstractThe work started by V. M. Maksimov [1970, Theory Probab. Appl. 15, 604–618], and continued by A. Mukherjea [1980, Trans. Amer. Math. Soc. 263, 505–520], is extended, and completed with respect to certain aspects. Infinite-dimensional stochastic chains are considered in the framework of Mukherjea [loc. cit.]; backward products of stochastic matrices and their convergence are also considered. The main theme centers around understanding how the convergence of products (backward and forward, finite and infinite dimensional) takes place and what it means in terms of various types of asymptotic behavior of the individual stochastic matrices in the chain. The study is based on establishing the existence of a basis for convergent chains. The basis then makes it possible to describe properly various aspects of convergence. All results are new; they are also complete at least in the sense they have been presented and suitable examples (or counter-examples) are presented to justify the assumptions involved

Studying HIV Risk in Vulnerable Communities: Methodological and Reporting Shortcomings in the Young Men’s Study in New York City

This article considers demographic categories used in the Young Men’s Study on HIV risk for men who have sex with men. We critique oversimplified pan-ethnic categories and the polarization of US racial discourse. We also interrogate the use of certain gender and sexuality markers that produced confusing results in this study. We use a critical standpoint derived from cultural studies to suggest that quantitative and qualitative methods of studying health risks and intimate behaviors in vulnerable populations require reorganization to more accurately represent the lives of members of these groups. Interviews, surveys, and statistics can be crude and lacking in practical information. Finally, we address media and governmental response to the Young Men’s Study, and the continued need for organizing across minoritized communities

From braid groups to mapping class groups

In this paper, we classify homomorphisms from the braid group of $n$ strands to the mapping class group of a genus $g$ surface. In particular, we show that when $g<n-2$, all representations are either cyclic or standard. Our result is sharp in the sense that when $g=n-2$, a generalization of the hyperelliptic representation appears. This gives a classification of genus $g$ surface bundles over the configuration space of the complex plane. As a corollary, we recover partially the result of Aramayona-Souto with a slight improvement, which classifies homomorphisms between mapping class groups.Comment: 25 pages, 3 figure

Nature of Enzyme-Matrix Binding in Trypsin Immobilized on Molecular Sieve Type 4A

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The endocannabinoid/cannabinoid receptor 2 system protects against cisplatin-induced hearing loss

Previous studies have demonstrated the presence of cannabinoid 2 receptor (CB2R) in the rat cochlea which was induced by cisplatin. In an organ of Corti-derived cell culture model, it was also shown that an agonist of the CB2R protected these cells against cisplatin-induced apoptosis. In the current study, we determined the distribution of CB2R in the mouse and rat cochleae and examined whether these receptors provide protection against cisplatin-induced hearing loss. In a knock-in mouse model expressing the CB2R tagged with green fluorescent protein, we show distribution of CB2R in the organ of Corti, stria vascularis, spiral ligament and spiral ganglion cells. A similar distribution of CB2R was observed in the rat cochlea using a polyclonal antibody against CB2R. Trans-tympanic administration of (2-methyl-1-propyl-1H-indol-3-yl)-1-naphthalenylmethanone (JWH015), a selective agonist of the CB2R, protected against cisplatin-induced hearing loss which was reversed by blockade of this receptor with 6-iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indol-3-yl](4-methoxyphenyl)methanone (AM630), an antagonist of CB2R. JWH015 also reduced the loss of outer hair cells (OHCs) in the organ of Corti, loss of inner hair cell (IHC) ribbon synapses and loss of Na+/K+-ATPase immunoreactivity in the stria vascularis. Administration of AM630 alone produced significant hearing loss (measured by auditory brainstem responses) which was not associated with loss of OHCs, but led to reductions in the levels of IHC ribbon synapses and strial Na+/K+-ATPase immunoreactivity. Furthermore, knock-down of CB2R by trans-tympanic administration of siRNA sensitized the cochlea to cisplatin-induced hearing loss at the low and middle frequencies. Hearing loss induced by cisplatin and AM630 in the rat was associated with increased expression of genes for oxidative stress and inflammatory proteins in the rat cochlea. In vitro studies indicate that JWH015 did not alter cisplatin-induced killing of cancer cells suggesting this agent could be safely used during cisplatin chemotherapy. These data unmask a protective role of the cochlear endocannabinoid/CB2R system which appears tonically active under normal conditions to preserve normal hearing. However, an exogenous agonist is needed to boost the activity of endocannabinoid/CB2R system for protection against a more traumatic cochlear insult, as observed with cisplatin administration.</p