Change Impact Analysis: A Tool for Effective Regression Testing

Change impact analysis is an imperative activity for the maintenance of software. It determines the set of modules that are changed and modules that are affected by the change(s). It helps in regression testing because only those modules that are either changed or affected by the suggested change(s) are retested. Change impact analysis is a complex activity as it is very difficult to predict the impact of a change in software. Different researchers have proposed different change impact analysis approaches that help in prioritization of test cases for regression testing. In this paper, an approach based on Total Importance of Module (TIM) has been proposed that determines the importance of a module on the basis of (i) user requirements, and (ii) system requirements. The results of the proposed algorithm showed that the importance of a module is an essential attribute in forming a prioritized test suite for regression testing

Pair-Wise Time-Aware Test Case Prioritization for Regression Testing

After maintenance, software requires regression testing for its validation. Prioritization of test cases for regression testing is required as software is tested under strict time and other constraints. A Pair-wise time-aware Test Case Prioritization (PTCP) technique has been proposed in this paper that determines the effectiveness of a test case on the basis of total number of faults present in software, number of faults detected till time, and the time of execution of different test cases. It selects that test case which determines maximum new faults, not yet detected, within minimum time. Thus prioritized test suite contains those test cases which are effective and tend to minimize repetitive faults detection. Through two comparative studies, it has been observed that with least wastage of time, the proposed technique performed equally well as other two parallel prioritizing techniques, Average Percentage of Fault Detection (APFD) based prioritization, and Optimal Test Case Prioritization (OTCP)

Role of Quality Source Code Documentation in Software Testing

Software testing is performed to validate that software under test meets all requirements. With the increase in software developing platforms, developers may commit those errors, which, if not tested with appropriate test cases, may lead to false confidence in software testing. In this paper, we proposed that building quality source code documentation can help in predicting such errors. To validate this proposal, we performed an initial study and found that if software is well documented, a tester may predict the possible set of errors that developers may commit, and hence, may select better test cases that target those faults. From this study, it has been observed that proper code documentation can help in selecting appropriate test cases from candidate test cases and can lead to more effective software testing

How Time-Fault Ratio helps in Test Case Prioritization for Regression Testing

Regression testing analyzes whether the maintenance of the software has adversely affected its normal functioning. Regression testing is generally performed under the strict time constraints. Due to limited time budget, it is not possible to test the software with all available test cases. Thus, the reordering of the test cases, on the basis of their effectiveness, is always needed. A test prioritization technique, which prioritizes the test cases on the basis of their Time -Fault Ratio (TFR), has been proposed in this paper. The technique tends to maximize the fault detection as the faults are exposed in the ascending order of their detection times. The proposed technique may be used at any stage of software development

Unilateral prurigo nodularis: a rare presentation

Prurigo Nodularis (PN) is a rare chronic skin disorder of unknown etiology. Here we are describing a case of 14 year old girl having prurigo nodularis with no other systemic illness

Changing epidemiology of dengue in South-East Asia

ABSTRACT The burden of dengue and its potential threat to global health are now globally recognized, with 2.5 billion people at risk worldwide. The pathogenesis of severe dengue is particularly intriguing with the involvement of different immune factors. Also, the epidemiology of dengue in South-East Asia is undergoing a change in the human host, the dengue virus and the vector bionomics. Shift in affected age groups, sex differences and expansion to rural areas are evident, while the virulence and genotype of the virus determine the severity and time interval between sequential infections. The Aedes mosquito, a potent and adaptive vector, has evolved in longevity and survival, affected by seasonality and climate variability, socio-cultural and economic factors of human habitation and development. This review provides insights into the changing epidemiology and its factors in South-East Asia, one of the most important epicentres of dengue in the world, highlighting the major factors influencing these rapid changes. Addressing the changes may help mitigate the challenges in the current dengue control and prevention efforts

Spektralna analiza poopćene trokutaste i Welchove prozorske funkcije korištenjem frakcijske Fourierove transformacije

The paper presents a new closed-form expression for the fractional Fourier transform of generalized Triangular and Welch window functions. Fractional Fourier Transform (FrFT) is a parameterized transform having an adjustable transform parameter which makes it more flexible and superior over ordinary Fourier transform in several applications. It is an important tool used in signal processing for spectral analysis. The analysis of generalized Triangular and Welch window functions in fractional Fourier domain establishes a direct relationship between their FrFTs and fractional angle. Based on the mathematical model obtained, it is observed that adjustable spectral parameters of these functions can be obtained by modifying the fractional angle. The various values of spectral parameters such as half main-lobe width, side lobe fall-off rate and maximum side-lobe level with change in order of fractional Fourier transform are also obtained for these functions.U radu je prikazan novi izraz za zatvoreni oblik frakcijske Fourierove transformacije poopćene trokutaste i Welchove prozorske funkcije. Frakcijska Fourierova transformacija (FrFT) parametrizirana je transformacija s podesivim parametrom transformacije koja je u određenim primjenama fleksibilnija i superiornija u odnosu na uobičajenu Fourierovu transformaciju. Ističe se kao važan alat u obradi signala i spektralnoj analizi. Analiza poopćene trokutaste i Welchove prozorske funkcije u području frkacijske Fourierove transformacije uspostavlja izravni odnos između FrFT-a i frakcijskog kuta. Koristeći dobiveni matematički model, uočeno je da se podesivi spektralni parametri ovih funkcija mogu izvesti mijenjanjem frakcijskog kuta. Različite vrijednosti spektralnih parametara, kao što su polovica širine spektralnog vrha, stopa snižavanja amplituda viših harmonika ili najveća amplituda viših harmonika, odnosno njihova ovisnost u odnosu na red frakcijske Fourierove transformacije, također se mogu odrediti upotrebom ovih funkcija

Performance criteria for verbal autopsy-based systems to estimate national causes of death: development and application to the Indian Million Death Study.

BACKGROUND: Verbal autopsy (VA) has been proposed to determine the cause of death (COD) distributions in settings where most deaths occur without medical attention or certification. We develop performance criteria for VA-based COD systems and apply these to the Registrar General of India's ongoing, nationally-representative Indian Million Death Study (MDS). METHODS: Performance criteria include a low ill-defined proportion of deaths before old age; reproducibility, including consistency of COD distributions with independent resampling; differences in COD distribution of hospital, home, urban or rural deaths; age-, sex- and time-specific plausibility of specific diseases; stability and repeatability of dual physician coding; and the ability of the mortality classification system to capture a wide range of conditions. RESULTS: The introduction of the MDS in India reduced the proportion of ill-defined deaths before age 70 years from 13% to 4%. The cause-specific mortality fractions (CSMFs) at ages 5 to 69 years for independently resampled deaths and the MDS were very similar across 19 disease categories. By contrast, CSMFs at these ages differed between hospital and home deaths and between urban and rural deaths. Thus, reliance mostly on urban or hospital data can distort national estimates of CODs. Age-, sex- and time-specific patterns for various diseases were plausible. Initial physician agreement on COD occurred about two-thirds of the time. The MDS COD classification system was able to capture more eligible records than alternative classification systems. By these metrics, the Indian MDS performs well for deaths prior to age 70 years. The key implication for low- and middle-income countries where medical certification of death remains uncommon is to implement COD surveys that randomly sample all deaths, use simple but high-quality field work with built-in resampling, and use electronic rather than paper systems to expedite field work and coding. CONCLUSIONS: Simple criteria can evaluate the performance of VA-based COD systems. Despite the misclassification of VA, the MDS demonstrates that national surveys of CODs using VA are an order of magnitude better than the limited COD data previously available

Prefix-based Application of Policies to Objects in Cloud Storage

Customer-created objects in cloud storage buckets are stored in a flat namespace and lack the hierarchy found in folders of a traditional file system. While grouped permissions are straightforward in a file system, such permissions are relatively difficult to implement in storage systems with flat namespaces, where policies can be applied at no finer a granularity than the level of the bucket. This disclosure describes a mechanism for applying a policy to a group of objects in a storage bucket based on the prefix of the objects. Customers can identify a prefix of the object path that ends in slash (/) and apply policies based on that prefix. The described techniques enable the application of policies to objects at a level of granularity that is finer than that of the storage bucket. A customer of cloud-based storage can purchase fewer storage buckets to organize a greater number and diversity of objects, thereby reducing cost and complexity and improving scalability