Internet of Things (IoT) systems are becoming prevalent in various domains, from healthcare to smart homes. Testing IoT systems is critical in ensuring their reliability. Previous papers studied ...separately the objectives, approaches, tools, and challenges of IoT systems testing. However, despite the rapid evolution of the IoT domain, no review has been undertaken to investigate all four aspects collectively. This paper presents a systematic literature review that aggregates, synthesizes, and discusses the results of 83 primary studies (PSs) concerning IoT testing objectives, approaches, tools, and challenges. We followed the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) protocol to report our findings and answer research questions (RQs). To select PSs, we applied inclusion and exclusion criteria to relevant studies published between 2012 and 2022. We extracted and analyzed the data from PSs to understand IoT systems testing. The results reveal that IoT systems testing embraces traditional software quality attributes but also introduces new ones like connectivity, energy efficiency, device lifespan, distributivity, and dynamicity. They also show that existing IoT systems testing approaches are limited to specific aspects and should be expanded for more comprehensive testing. They also show 19 testing tools and 15 testbeds for testing IoT systems with their limitations, necessitating the development or enhancement for wider coverage. The large number of heterogeneous devices generating data in different formats, along with the need for testing in real-world scenarios, poses a challenge. Thus, our study offers insights into the testing objectives, approaches, tools, and challenges associated with IoT systems. Based on the results, we also provide practical guidance for IoT practitioners by cataloging existing tools and approaches, while also identifying new research opportunities for interested researchers.
Performing non-destructive testing on metallic components with very complex geometries, such as turbine blades, is very challenging. To inspect such components, powerful and robust non-destructive ...inspection protocols must be defined. Process Compensated Resonance Testing (PCRT) is a relatively novel approach that records a broadband vibrational fingerprint for each component and employs vibrational features such as resonant frequency, quality factor, and amplitude. These features are used in the Mahalanobis Taguchi System to classify the parts in terms of their quality, i.e. Good/Bad.
In the present study, a two-stage MCS classification approach, coupled with Binary Particle Swarm Optimization, is proposed to optimize the process of selecting the most significant features and to search for the optimal decision boundary to discriminate healthy and unhealthy components. Further, the proposed MCS enables the features to be mapped into a higher dimensional Mahalanobis Distance space, thereby enhancing the performance of classification. An experimental case study on equiaxed Nickel alloy first-stage turbine blades, with very complex geometry and various damages, demonstrates the high classification accuracy and robustness of the developed MCS approach.
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•Two 2.25 MHz ultrasonic transducers.•Acoustic field analysis.•Defect detection simulation by CIVA software.•Artificial and natural defect detection.•Comparison with radiographic ...testing.
In this study, a phased array ultrasonic system for detecting rail cracks (PAUSR) was developed which consists of two phased array (PA) ultrasonic transducers, a water tank, a display monitor, a battery, a commercial 64 channel PA board, and its control software. To accomplish this, the acoustic fields and crack detection images of newly developed PA ultrasonic transducers were simulated and analyzed by the CIVA (CIVA 2016, NDE CIVA, USA) software. The major design factors for the PAUSR is the capability of evaluating crack size (over 2 mm), generating proper acoustic fields in the rail and easy and safe handling for operators. For the performance test of the designed PA ultrasonic transducer, Non-destructive Characterization and Verification of Ultrasonic Phased Array Equipment, Part 2: Probes (EN ISO 18563-2:2017) was conducted. In addition, artificial crack detection images were simulated by the CIVA software, and an experiment under the same CIVA simulation conditions was also performed for comparison purposes. For the last verification, natural defective specimens with bolt-hole star-cracking, longitudinal vertical cracking and welding defects were scanned by the developed PAUSR, and its results were analyzed and compared with the radiographic testing (RT) and CIVA simulation outcomes.
•We address the topic of fully automatic event-based testing of Android mobile apps.•We present a framework abstracting common characteristics of testing techniques.•We recast 38 existing Android ...online testing techniques according to the framework.•The framework is usable for designing experiments and comparing testing techniques.•We experimentally compare performance of automatic techniques using the framework.
As an increasing number of new techniques are developed for quality assurance of Android applications (apps), there is a need to evaluate and empirically compare them. Researchers as well as practitioners will be able to use the results of such comparative studies to answer questions such as, “What technique should I use to test my app?” Unfortunately, there is a severe lack of rigorous empirical studies on this subject. In this paper, for the first time, we present an empirical study comparing all existing fully automatic “online” testing techniques developed for the Android platform. We do so by first reformulating each technique within the context of a general framework. We recognize the commonalities between the techniques to develop the framework. We then use the salient features of each technique to develop parameters of the framework. The result is a general recasting of all existing approaches in a plug-in based formulation, allowing us to vary the parameters to create instances of each technique, and empirically evaluate them on a common set of subjects. Our results show that (1) the proposed general framework abstracts all the common characteristics of online testing techniques proposed in the literature, (2) it can be exploited to design experiments aimed at performing objective comparisons among different online testing approaches and (3) some parameters that we have identified influence the performance of the testing techniques.
Although awareness of familial hypercholesterolemia (FH) is increasing, this common, potentially fatal, treatable condition remains underdiagnosed. Despite FH being a genetic disorder, genetic ...testing is rarely used. The Familial Hypercholesterolemia Foundation convened an international expert panel to assess the utility of FH genetic testing. The rationale includes the following: 1) facilitation of definitive diagnosis; 2) pathogenic variants indicate higher cardiovascular risk, which indicates the potential need for more aggressive lipid lowering; 3) increase in initiation of and adherence to therapy; and 4) cascade testing of at-risk relatives. The Expert Consensus Panel recommends that FH genetic testing become the standard of care for patients with definite or probable FH, as well as for their at-risk relatives. Testing should include the genes encoding the low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9); other genes may also need to be considered for analysis based on patient phenotype. Expected outcomes include greater diagnoses, more effective cascade testing, initiation of therapies at earlier ages, and more accurate risk stratification.
COVID-19 testing: One size does not fit all Mina, Michael J; Andersen, Kristian G
Science (American Association for the Advancement of Science),
01/2021, Volume:
371, Issue:
6525
Journal Article
Peer reviewed
Open access
To control the pandemic, testing should be considered a public health tool
Tests for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were developed within days of the release ...of the virus genome (
1
). Multiple countries have been successful at controlling SARS-CoV-2 transmission by investing in large-scale testing capacity (
2
). Most testing has focused on quantitative polymerase chain reaction (qPCR) assays, which are capable of detecting minute amounts of viral RNA. Although powerful, these molecular tools cannot be scaled to meet demands for more extensive public health testing. To combat COVID-19, the “one-size-fits-all” approach that has dominated and confused decision-making with regard to testing and the evaluation of tests is unsuitable: Diagnostics, screening, and surveillance serve different purposes, demand distinct strategies, and require separate approval mechanisms. By supporting the innovation, approval, manufacturing, and distribution of simpler and cheaper screening and surveillance tools, it will be possible to more effectively limit the spread of COVID-19 and respond to future pandemics.
The non-destructive testing of concrete structures with methods such as ultrasonic pulse velocity and Schmidt rebound hammer test is of utmost technical importance. Non-destructive testing methods do ...not require sampling, and they are simple, fast to perform, and efficient. However, these methods result in large dispersion of the values they estimate, with significant deviation from the actual (experimental) values of compressive strength. In this paper, the application of artificial neural networks (ANNs) for predicting the compressive strength of concrete in existing structures has been investigated. ANNs have been systematically used for predicting the compressive strength of concrete, utilizing both the ultrasonic pulse velocity and the Schmidt rebound hammer experimental results, which are available in the literature. The comparison of the ANN-derived results with the experimental findings, which are in very good agreement, demonstrates the ability of ANNs to estimate the compressive strength of concrete in a reliable and robust manner. Thus, the (quantitative) values of weights for the proposed neural network model are provided, so that the proposed model can be readily implemented in a spreadsheet and accessible to everyone interested in the procedure of simulation.
Toxicity Testing in the 21st Century National Research Council; Division on Earth and Life Studies; Institute for Laboratory Animal Research ...
03/2009
eBook
Open access
Advances in molecular biology and toxicology are paving the way for major improvements in the evaluation of the hazards posed by the large number of chemicals found at low levels in the environment. ...The National Research Council was asked by the U.S. Environmental Protection Agency to review the state of the science and create a far-reaching vision for the future of toxicity testing. The book finds that developing, improving, and validating new laboratory tools based on recent scientific advances could significantly improve our ability to understand the hazards and risks posed by chemicals. This new knowledge would lead to much more informed environmental regulations and dramatically reduce the need for animal testing because the new tests would be based on human cells and cell components. Substantial scientific efforts and resources will be required to leverage these new technologies to realize the vision, but the result will be a more efficient, informative and less costly system for assessing the hazards posed by industrial chemicals and pesticides.
Understanding the effect of serum antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on susceptibility to infection is important for identifying at-risk populations and could ...have implications for vaccine deployment.
The study purpose was to evaluate evidence of SARS-CoV-2 infection based on diagnostic nucleic acid amplification test (NAAT) among patients with positive vs negative test results for antibodies in an observational descriptive cohort study of clinical laboratory and linked claims data.
The study created cohorts from a deidentified data set composed of commercial laboratory tests, medical and pharmacy claims, electronic health records, and hospital chargemaster data. Patients were categorized as antibody-positive or antibody-negative according to their first SARS-CoV-2 antibody test in the database.
Primary end points were post-index diagnostic NAAT results, with infection defined as a positive diagnostic test post-index, measured in 30-day intervals (0-30, 31-60, 61-90, >90 days). Additional measures included demographic, geographic, and clinical characteristics at the time of the index antibody test, including recorded signs and symptoms or prior evidence of coronavirus 2019 (COVID) diagnoses or positive NAAT results and recorded comorbidities.
The cohort included 3 257 478 unique patients with an index antibody test; 56% were female with a median (SD) age of 48 (20) years. Of these, 2 876 773 (88.3%) had a negative index antibody result, and 378 606 (11.6%) had a positive index antibody result. Patients with a negative antibody test result were older than those with a positive result (mean age 48 vs 44 years). Of index-positive patients, 18.4% converted to seronegative over the follow-up period. During the follow-up periods, the ratio (95% CI) of positive NAAT results among individuals who had a positive antibody test at index vs those with a negative antibody test at index was 2.85 (95% CI, 2.73-2.97) at 0 to 30 days, 0.67 (95% CI, 0.6-0.74) at 31 to 60 days, 0.29 (95% CI, 0.24-0.35) at 61 to 90 days, and 0.10 (95% CI, 0.05-0.19) at more than 90 days.
In this cohort study, patients with positive antibody test results were initially more likely to have positive NAAT results, consistent with prolonged RNA shedding, but became markedly less likely to have positive NAAT results over time, suggesting that seropositivity is associated with protection from infection. The duration of protection is unknown, and protection may wane over time.
In 1995, the American Society of Human Genetics (ASHG) and American College of Medical Genetics and Genomics (ACMG) jointly published a statement on genetic testing in children and adolescents. In ...the past 20 years, much has changed in the field of genetics, including the development of powerful new technologies, new data from genetic research on children and adolescents, and substantial clinical experience. This statement represents current opinion by the ASHG on the ethical, legal, and social issues concerning genetic testing in children. These recommendations are relevant to families, clinicians, and investigators. After a brief review of the 1995 statement and major changes in genetic technologies in recent years, this statement offers points to consider on a broad range of test technologies and their applications in clinical medicine and research. Recommendations are also made for record and communication issues in this domain and for professional education.
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