Modeling of flexible manufacturing tooling system with reliability considerations.

In the planning process of flexible manufacturing systems (FMS), an FMS must not be designed to fulfill its intended functions only, but also to perform the intended functions successfully. The latter requires the design of reliability into the system. The decisions involving the number of tools and tool redundancies need to be carried and executed in real time. This research discusses FMS tooling reliability in the context of the machine loading and part assignment problem. As manufacturing systems become more and more complex, competition and cost grow even more rapidly. Flexible manufacturing systems became the means to narrow the gap between the various different pressures. FMS promises more efficient and effective ways of utilizing resources, information and assets, due to its capability to carry a variety of different tools so that it can perform different operations required in the production of a variety of low to mid size part types. Integer-programming models are developed. The formulations consider an objective function with a set of governing constraints. A reliability level is decided for the tooling system, the models then will return with optimum number of tools and tool copies for each tool type. The overall objective is cost minimization while achieving maximum desired tooling system for the FMS under consideration. Two distinct scenarios are studied, the first considers an FMS where tool sharing is not allowed which implies that each tool magazine will be required to carry the required tools and tool copies to achieve the reliability levels decided and to carry the required machining operations on the different parts assigned to it during each production period. The second scenario is where tool sharing is permitted; in this case if a tool is not available on a particular tool magazine it can be borrowed from another magazine or from the tool crib. Two Genetic algorithms are developed and used to solve the two cases, the solutions are compared to solutions obtained by LINGO optimization software and conclusions are derived. The research conducted in this thesis is aimed at developing cost minimization models for the part assignment and tool loading in flexible manufacturing systems with reliability considerations. The thesis of this research states that tooling system reliability can be integrated in FMS planning decisions, and that such models will complement some of the apparent limitations in the existing models. The models aim at assessing decision-maker to decide a minimum tooling system reliability and to optimize overall processing and tooling cost of the part assignment and tool loading of FMS. A solution methodology is also presented in this thesis. The solution takes into account part assignment and tool loading along with tooling system reliability of FMS under consideration.Dept. of Industrial and Manufacturing Systems Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2001 .A48. Source: Dissertation Abstracts International, Volume: 63-04, Section: B, page: 2009. Adviser: S. M. Taboon. Thesis (Ph.D.)--University of Windsor (Canada), 2001

A Scoping Review of Research Ethics and Practices in Library and Information Science in Scopus and Library and Information Science Source Databases

Introduction and Background: Library and information science scholars are partially aware of the research ethics regarding data falsification, fabrication, data cooking, gifted authorship, neglected authorship, and other factors. Such activities are not only unethical but may equally cause harm to the academic community and society. Purpose: This paper aims to identify the gaps in studies focusing on research ethics and practices in Library and Information Science in the Scopus and Library and Information Science Source Databases. The review seeks to respond to research questions such as what is the scope of articles focusing on research ethics and practices between 2011 and 2021; what are the features of articles focusing on research ethics and practices in the Scopus and LISS domain; to what extent is the African research on ethics and practices and LISS reflected in the domain; and what are the implications of studies focusing on research ethics as reported in the identified literature? Methodology: Databases searched include the Scopus and Library and Information Science Source for articles published between 2011 and 2021. Advanced search strategies are used as well as thematic analysis. Result: Out of 190 documents identified from the databases, 70 were eligible for review while 13 were included in the scoping review. The majority of the articles focusing on research ethics and practices were published between 2016 and 2021. The year 2021 witnessed the highest number of publications, while the lowest was in 2014. The majority of studies published in the LIS domain emerged from developed countries. However, few were published by African scholars in Scopus and LISS focusing on research ethics and practices. Implications: This paper has implications for LIS researchers and policymakers. Practical implications include the control and reduction of data falsifications, data cooking, and unethical research practices among LIS researchers. Implications for efficient knowledge management for sustainable development are also prominent in this paper. Conclusions: Given that limited articles focus on the subject identified in the domain, African scholars need to contribute immensely towards literature addressing research ethics. They also need to engage the researchers, information managers, and policymakers to empower librarians with knowledge of how to manage scholarly publications in academic libraries

Proposed Solutions for the Main Challenges and Security Issues in IoT Smart Home Technology

The IoT has become a trend in recent years, and the smart home system has achieved great interest due to its need and requirement from consumers around the world. Smart home technology refers to the devices that are connected over the internet to monitor, support, and control the home in order to make our life easier. The revolution in technology has made homes more convenient, efficient, and even simpler. However, there are some challenges and obstacles that need to take into consideration when using a smart home system. Based on a comprehensive survey, this study aims to provide an overview of the critical security issues for IoT smart home systems and propose potential solutions to mitigate these risks by understanding vulnerabilities and applying security measures to ensure that the IoT system is more reliable and safe. The challenges and security issues highlighted with an emphasis on providing solutions, as well as smart home approaches and IoT layers

A comparison of Sinogram Affirmed Iterative Reconstruction and filtered back projection on image quality and dose reduction in paediatric head CT: a phantom study

Background: Computed tomography (CT) is one of the most used modalities for diagnostics in paediatric populations, which is a concern as it also delivers a high patient dose. Research has focused on developing computer algorithms that provide better image quality at lower dose. The iterative reconstruction algorithm Sinogram-Affirmed Iterative Reconstruction (SAFIRE) was introduced as a new technique that reduces noise to increase image quality. Purpose: The aim of this study is to compare SAFIRE with the current gold standard, Filtered Back Projection (FBP), and assess whether SAFIRE alone permits a reduction in dose while maintaining image quality in paediatric head CT. Methods: Images were collected using a paediatric head phantom using a SIEMENS SOMATOM PERSPECTIVE 128 modulated acquisition. 54 images were reconstructed using FBP and 5 different strengths of SAFIRE. Objective measures of image quality were determined by measuring SNR and CNR. Visual measures of image quality were determined by 17 observers with different radiographic experiences. Images were randomized and displayed using 2AFC; observers scored the images answering 5 questions using a Likert scale. Results: At different dose levels, SAFIRE significantly increased SNR (up to 54%) in the acquired images compared to FBP at 80kVp (5.2-8.4), 110kVp (8.2-12.3), 130kVp (8.8-13.1). Visual image quality was higher with increasing SAFIRE strength. The highest image quality was scored with SAFIRE level 3 and higher. Conclusion: The SAFIRE algorithm is suitable for image noise reduction in paediatric head CT. Our data demonstrates that SAFIRE enhances SNR while reducing noise with a possible reduction of dose of 68%

The impact of Sinogram-Affirmed Iterative Reconstruction on patient dose and image quality compared to filtered back projection: a narrative review

Objective: Summarize all relevant findings in published literature regarding the potential dose reduction related to image quality using Sinogram-Affirmed Iterative Reconstruction (SAFIRE) compared to Filtered Back Projection (FBP). Background: Computed Tomography (CT) is one of the most used radiographic modalities in clinical practice providing high spatial and contrast resolution. However it also delivers a relatively high radiation dose to the patient. Reconstructing raw-data using Iterative Reconstruction (IR) algorithms has the potential to iteratively reduce image noise while maintaining or improving image quality of low dose standard FBP reconstructions. Nevertheless, long reconstruction times made IR unpractical for clinical use until recently. Siemens Medical developed a new IR algorithm called SAFIRE, which uses up to 5 different strength levels, and poses an alternative to the conventional IR with a significant reconstruction time reduction. Methods: MEDLINE, ScienceDirect and CINAHL databases were used for gathering literature. Eleven articles were included in this review (from 2012 to July 2014). Discussion: This narrative review summarizes the results of eleven articles (using studies on both patients and phantoms) and describes SAFIRE strengths for noise reduction in low dose acquisitions while providing acceptable image quality. Conclusion: Even though the results differ slightly, the literature gathered for this review suggests that the dose in current CT protocols can be reduced at least 50% while maintaining or improving image quality. There is however a lack of literature concerning paediatric population (with increased radiation sensitivity). Further studies should also assess the impact of SAFIRE on diagnostic accuracy

10 kVp rule - an anthropomorphic pelvis phantom imaging study using a CR system : impact on image quality and effective dose using AEC and manual mode

Purpose: This study aims to investigate the influence of tube potential (kVp) variation in relation to perceptual image quality and effective dose for pelvis using automatic exposure control (AEC) and non-AEC in a Computed Radiography (CR) system. Methods and Materials: To determine the effects of using AEC and non-AEC by applying the 10 kVp rule in two experiments using an anthropomorphic pelvis phantom. Images were acquired using 10kVp increments (60-120kVp) for both experiments. The first experiment, based on seven AEC combinations, produced 49 images. The mean mAs from each kVp increment were used as a baseline for the second experiment producing 35 images. A total of 84 images were produced and a panel of 5 experienced observers participated for the image scoring using the 2AFC visual grading software. PCXMC software was used to estimate the effective dose. Results: A decrease in perceptual image quality as the kVp increases was observed both in non-AEC and AEC experiments, however no significant statistical differences (p>0.05) were found. Image quality scores from all observers at 10 kVp increments for all mAs values using non-AEC mode demonstrates a better score up to 90kVp. Effective dose results show a statistical significant decrease (p=0.000) on the 75th quartile from 0.3 mSv at 60 kVp to 0.1 mSv at 120kVp when applying the 10 kVp rule in non-AEC mode. Conclusion(s): No significant reduction in perceptual image quality is observed when increasing kVp whilst a marked and significant effective dose reduction is observed