Moving Towards Analog Functional Safety

Over the past century, the exponential growth of the semiconductor industry has led to the creation of tiny and complex integrated circuits, e.g., sensors, actuators, and smart power systems. Innovative techniques are needed to ensure the correct functionality of analog devices that are ubiquitous in every smart system. The standard ISO 26262 related to functional safety in the automotive context specifies that fault injection is necessary to validate all electronic devices. For decades, standardizing fault modeling, injection and simulation mainly focused on digital circuits and disregarding analog ones. An initial attempt is being made with the IEEE P2427 standard draft standard that started to give this field a structured and formal organization. In this context, new fault models, injection, and abstraction methodologies for analog circuits are proposed in this thesis to enhance this application field. The faults proposed by the IEEE P2427 standard draft standard are initially evaluated to understand the associated fault behaviors during the simulation. Moreover, a novel approach is presented for modeling realistic stuck-on/off defects based on oxide defects. These new defects proposed are required because digital stuck-at-fault models where a transistor is frozen in on-state or offstate may not apply well on analog circuits because even a slight variation could create deviations of several magnitudes. Then, for validating the proposed defects models, a novel predictive fault grouping based on faulty AC matrices is applied to group faults with equivalent behaviors. The proposed fault grouping method is computationally cheap because it avoids performing DC or transient simulations with faults injected and limits itself to faulty AC simulations. Using AC simulations results in two different methods that allow grouping faults with the same frequency response are presented. The first method is an AC-based grouping method that exploits the potentialities of the S-parameters ports. While the second is a Circle-based grouping based on the circle-fitting method applied to the extracted AC matrices. Finally, an open-source framework is presented for the fault injection and manipulation perspective. This framework relies on the shared semantics for reading, writing, or manipulating transistor-level designs. The ultimate goal of the framework is: reading an input design written in a specific syntax and then allowing to write the same design in another syntax. As a use case for the proposed framework, a process of analog fault injection is discussed. This activity requires adding, removing, or replacing nodes, components, or even entire sub-circuits. The framework is entirely written in C++, and its APIs are also interfaced with Python. The entire framework is open-source and available on GitHub. The last part of the thesis presents abstraction methodologies that can abstract transistor level models into Verilog-AMS models and Verilog- AMS piecewise and nonlinear models into C++. These abstracted models can be integrated into heterogeneous systems. The purpose of integration is the simulation of heterogeneous components embedded in a Virtual Platforms (VP) needs to be fast and accurate

The Relationship between Ownership Structure and Capital Structure: Evidence from Chemical Sector of Pakistan

Objective – The main objective of this study is to measure the relationship between ownership structure and capital structure by using the chemical sector of Pakistan. Design – This study is used the panel data and retrieved from the annual reports of the chemical sector of Pakistan for the time period of 2012 to 2017. Findings – The finding the statistical analysis shows that ownership structure has a significant positive relationship on capital structure. Which mitigate the agency conflicts among managers and shareholders, because the majority of the shareholders would like to have a higher level of debt over equity financing. Policy Implications – The findings of this study also can be helpful to the policymakers, investors and financial institution in designing ownership structures and financing decisions for firms.  Originality – This is the first study that examined the relationship between ownership structure and capital structure in the context of the chemical sector of Pakistan

A Comparative Analysis of Populist Regimes in Pakistan and Turkey

Populist governments are mainly driven by economic setbacks, traditional rivalries with their political opponents and authoritarian political strategies to overcome any potential challenge to their legitimacy. In this context, the government of Imran Khan in Pakistan and Recep Tayyip Erdogan in Turkey are two distinct case studies whose regimes have adopted a populist posture in their political practices. This research by focusing on these two case studies, primarily highlights that what happens when populists are in power? Secondly, this paper intends to explain that how populist discourse over shadowed their governance and political communication. Despite the fact that they have large leadership following but their political oratory has failed to build a national resolve for the common masses

Analog Defect Injection and Fault Simulation Techniques: A Systematic Literature Review

Since the last century, the exponential growth of the semiconductor industry has led to the creation of tiny and complex integrated circuits, e.g., sensors, actuators, and smart power. Innovative techniques are needed to ensure the correct functionality of analog devices that are ubiquitous in every smart system. The ISO 26262 standard for functional safety in the automotive context specifies that fault injection is necessary to validate all electronic devices. For decades, standardization of defect modeling and injection mainly focused on digital circuits and, in a minor part, on analog ones. An initial attempt is being made with the IEEE P2427 draft standard that started to give a structured and formal organization to the analog testing field. Various methods have been proposed in the literature to speed up the fault simulation of the defect universe for an analog circuit. A more limited number of papers seek to reduce the overall simulation time by reducing the number of defects to be simulated. This literature survey describes the state-of-the-art of analog defect injection and fault simulation methods. The survey is based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodological flow, allowing for a systematic and complete literature survey. Each selected paper has been categorized and presented to provide an overview of all the available approaches. In addition, the limitations of the various approaches are discussed by showing possible future directions

Knowledge and practice of radiation safety among invasive cardiologists

OBJECTIVE: To assess the availability, practices and knowledge of radiation safety measures among invasive cardiologists in a tertiary care hospital. METHOD: A cross sectional survey of invasive cardiologists working in academic institutions was conducted using a questionnaire. RESULTS: A total of 28 cardiologists completed the questionnaire with a mean working experience of 10.5 + 7.6 years. All were of the opinion that radiation safety is extremely important and 93% always used lead aprons. Less than half of them used other radiation protective measures including thyroid collar, lead eyeglasses and lead shields. Only 7% regularly utilized a radiation dose badge to monitor the exposure. This may be related to the availability, as lead aprons are readily available but other devices i.e. lead glasses, lead shield and radiation dose badge is available to less than a third of them. On evaluating knowledge only one fourth knew more than 60% of the answers to questions testing the basic principles of radiation safety. When working experience of cardiologists was correlated with their knowledge and practice of radiation safety surprisingly a paradoxical relationship was noted. Mean number of correct answers in those with experience of \u3e 10 years vs \u3c 10 years was 45% vs 56%, p \u3c 0.03. All of the above findings are probably because less than 50% have received any formal education in this important field. CONCLUSIONS: There is a lack of standard radiation safety measures and equipments in cardiac catheterization laboratories. Significant lapses exist in practice and lack of knowledge of radiation safety among invasive cardiologists in this part of the world. With rapid growth in the number of cardiac catheterization laboratories in developing countries significant improvement in knowledge, practice and availability of radiation safety measures is needed

An in-vitro evaluation of skin protection factor of non-polar date seed extract from three different date varieties Ajwa, Aseel and Khapra by UV spectrophotometry

Objective: Skin is the primary layer of human body which act as protective barrier against exogenous chemicals, UV radiations as well as microorganisms. Maintaining the skin morphology under regular environmental stresses and controlling age related skin changes is one of the biggest challenges for modern science, pharmaceutical and cosmetics industry. These environmental stresses, such as excessive exposure to UV radiations, can even lead to the devastating skin disorders such as skin cancer. Dates seed has capability to protect skin against the damages caused by solar radiations, which mostly appear in the forms of wrinkles and some other skin related issues. Methods: Therefore, current research is focused on to analyze sun protection factor (SPF) of two non-polar fractions obtained from crushed seeds of three different varieties of i.e., Ajwa, Aseel and Khapra. Results: Results indicate that the highest value of SPF was found in AEA i.e., 15.061 at 200ppm while no difference was observed in the SPF values of KPPE. Conclusion: Hence, it could be concluded that the ethyl acetate fraction of all date seed varieties could be potential Ajwa, Aseel and Khapra could be a promising source of cosmetic and pharmaceutical preparations due to the potential SPF value except petroleum ether of Khapra extract

Expression of androgen receptor and cancer stem cell markers (CD44 +/CD24 - and ALDH1 +): Prognostic implications in invasive breast cancer

Background: Androgen receptor (AR) has emerged as a significant prognostic marker in early breast cancer (BCa). Association of AR with cancer stem cell (CSC) markers in BCa is unknown. Aim of the present study was to evaluate the immunohistochemical expression of AR, CD44, CD24 and ALDH1 in a cohort of Pakistani patients diagnosed with invasive BCa and to correlate the expression with 5- year disease free survival.Patients and methods: We evaluated immunohistochemical expression AR, CD44, CD24 and ALDH1 in formalin fixed paraffin embedded archival blocks of 166 cases of primary invasive BCa (stage I-III) and correlated the expression with clinicopathological variables and outcome using univariable and multivariable analysis. Survival data was computed by Kaplan Meier curves.Results: Expression of AR was observed in 62.7% tumors whereas CD44, CD24 and ALDH1 were expressed in 61.4%, 44% and 30.1% tumors, respectively. AR expression was significantly associated with T1-T2 tumors, lower grade, estrogen and progesterone receptor expression (P \u3c .05) and remained an independent prognostic indicator in multivariable analysis (adjusted HR 0.33, 95% CI 0.13-0.81; P = .016). Significant association was observed between concordant expression of AR and CD24 (P = .001) with a favorable impact on survival (P = .007) whereas expression of CSC phenotypes (CD44+, CD44+/CD24- and ALDH1+) did not correlate with adverse outcome (P \u3e .05). However, AR expression retained the association with better prognosis even in patients whose tumors exhibited a CSC phenotype.Conclusions: Expression of AR and CD24 in stage I-III invasive BCa correlates with favorable clinicopathological features and delineates a subgroup of patients with better disease-free survival

Oral Health Status Among Pregnant Women Attending Gynae OPD of Tertiary Care Hospital in Rawalpindi

Objective: The objectives of this study were to determine the oral health status and treatment needs using DMFT & CPITN indices in pregnant women attending Gynae OPD of tertiary care Hospital in Rawalpindi, to Determine Association of Oral health status using DMFT and CPITN with socioeconomic status and to determine oral health status of various trimesters of pregnancy Materials and methods: An analytical cross-sectional study was carried out to assess the oral health status and treatment needs among pregnant women at Tertiary Care Hospital, Rawalpindi from April’ 2020 to September’ 2020. Consecutive sampling was used to select the study participants. An adaptive version of WHO questionnaire was used. Results were presented in the form of frequency tables. Chi square test of statistics was applied to assess the association between categorical DMFT and CPITN with the sociodemographic characteristics of the participating females. Results: The mean DMFT score pregnant females was 2.41 + 2.30 and were belonged to a middle socioeconomic status 43.8% (n=173). About 61.8% (n=244) of participants had DMFT total score 1-7. Whereas, majority of the participants were reported bleeding gums on probing 30.6% (n=121) on assessment by CPITN. The participating pregnant females also depicted the worsening of periodontal tissues (P=0.00) and dentition status (P=0.02). Socioeconomic status was not significantly associated with dentition (P=0.39) and periodontal status (P=0.69). Conclusion: The study revealed that oral health status was deteriorated during pregnancy. Education and gestational period were strong indicator for oral health status among pregnant women. Bleeding gums were reported in majority of participants during second trimester of pregnancy. Socioeconomic status was not significantly associated with oral health status by CPITN and DMFT score