Design for prognostics and security in field programmable gate arrays (FPGAs).

There is an evolutionary progression of Field Programmable Gate Arrays (FPGAs) toward more complex and high power density architectures such as Systems-on- Chip (SoC) and Adaptive Compute Acceleration Platforms (ACAP). Primarily, this is attributable to the continual transistor miniaturisation and more innovative and efficient IC manufacturing processes. Concurrently, degradation mechanism of Bias Temperature Instability (BTI) has become more pronounced with respect to its ageing impact. It could weaken the reliability of VLSI devices, FPGAs in particular due to their run-time reconfigurability. At the same time, vulnerability of FPGAs to device-level attacks in the increasing cyber and hardware threat environment is also quadrupling as the susceptible reliability realm opens door for the rogue elements to intervene. Insertion of highly stealthy and malicious circuitry, called hardware Trojans, in FPGAs is one of such malicious interventions. On the one hand where such attacks/interventions adversely affect the security ambit of these devices, they also undermine their reliability substantially. Hitherto, the security and reliability are treated as two separate entities impacting the FPGA health. This has resulted in fragmented solutions that do not reflect the true state of the FPGA operational and functional readiness, thereby making them even more prone to hardware attacks. The recent episodes of Spectre and Meltdown vulnerabilities are some of the key examples. This research addresses these concerns by adopting an integrated approach and investigating the FPGA security and reliability as two inter-dependent entities with an additional dimension of health estimation/ prognostics. The design and implementation of a small footprint frequency and threshold voltage-shift detection sensor, a novel hardware Trojan, and an online transistor dynamic scaling circuitry present a viable FPGA security scheme that helps build a strong microarchitectural level defence against unscrupulous hardware attacks. Augmented with an efficient Kernel-based learning technique for FPGA health estimation/prognostics, the optimal integrated solution proves to be more dependable and trustworthy than the prevalent disjointed approach.Samie, Mohammad (Associate)PhD in Transport System

Hardware trojans and smart manufacturing – a hardware security perspective

Integrated Circuits (ICs) are the cardinal elements of modern electrical, electronic and electro-mechanical systems. Amid global outsourcing of ICs' design and fabrication and their growing applications in smart manufacturing or Industrie 4.0, various hardware security threats and issues of trust have also emerged. IC piracy, counterfeiting, and hardware Trojans (HTs) are some of the key hardware threats that merit the attention of manufacturing community. It is worth noting that the lower abstraction levels (ICs) are falsely assumed to operate securely. The proposition, therefore, is that if an operating system (higher abstraction level) is considered to be secure while operating on a compromised IC (lower abstraction level), would it be prudent to regard this implementation as secure? The purpose of this paper is to highlight IC level threats with an emphasis on hardware Trojans that pose a significant threat to smart manufacturing environment in the wake of Industrial Internet of Things (IIoT)

Physics of failure (PoF) based lifetime prediction of power electronics at the printed circuit board level

This paper presents the use of physics of failure (PoF) methodology to infer fast and accurate lifetime predictions for power electronics at the printed circuit board (PCB) level in early design stages. It is shown that the ability to accurately model silicon–metal layers, semiconductor packaging, printed circuit boards (PCBs), and assemblies allows, for instance, the prediction of solder fatigue failure due to thermal, mechanical, and manufacturing conditions. The technique allows a life-cycle prognosis of the PCB, taking into account the environmental stresses it will encounter during the period of operation. Primarily, it involves converting an electronic computer aided design (eCAD) circuit layout into computational fluid dynamic (CFD) and finite element analysis (FEA) models with accurate geometries. From this, stressors, such as thermal cycling, mechanical shock, natural frequency, and harmonic and random vibrations, are applied to understand PCB degradation, and semiconductor and capacitor wear, and accordingly provide a method for high-fidelity power PCB modelling, which can be subsequently used to facilitate virtual testing and digital twinning for aircraft systems and sub-system

Ingress of threshold voltage-triggered hardware trojan in the modern FPGA fabric–detection methodology and mitigation

The ageing phenomenon of negative bias temperature instability (NBTI) continues to challenge the dynamic thermal management of modern FPGAs. Increased transistor density leads to thermal accumulation and propagates higher and non-uniform temperature variations across the FPGA. This aggravates the impact of NBTI on key PMOS transistor parameters such as threshold voltage and drain current. Where it ages the transistors, with a successive reduction in FPGA lifetime and reliability, it also challenges its security. The ingress of threshold voltage-triggered hardware Trojan, a stealthy and malicious electronic circuit, in the modern FPGA, is one such potential threat that could exploit NBTI and severely affect its performance. The development of an effective and efficient countermeasure against it is, therefore, highly critical. Accordingly, we present a comprehensive FPGA security scheme, comprising novel elements of hardware Trojan infection, detection, and mitigation, to protect FPGA applications against the hardware Trojan. Built around the threat model of a naval warship’s integrated self-protection system (ISPS), we propose a threshold voltage-triggered hardware Trojan that operates in a threshold voltage region of 0.45V to 0.998V, consuming ultra-low power (10.5nW), and remaining stealthy with an area overhead as low as 1.5% for a 28 nm technology node. The hardware Trojan detection sub-scheme provides a unique lightweight threshold voltage-aware sensor with a detection sensitivity of 0.251mV/nA. With fixed and dynamic ring oscillator-based sensor segments, the precise measurement of frequency and delay variations in response to shifts in the threshold voltage of a PMOS transistor is also proposed. Finally, the FPGA security scheme is reinforced with an online transistor dynamic scaling (OTDS) to mitigate the impact of hardware Trojan through run-time tolerant circuitry capable of identifying critical gates with worst-case drain current degradation

Comparative Efficacy of Chitosan with or Without Honey on Cutaneous Wound Healing in Donkeys

The domesticated donkey, derived from the African wild ass, has played a crucial role in human history for over 5,000 years, serving as a working and pack animal. However, donkeys often suffer from skin wounds and injuries due to various factors, including equipment use, road accidents, and lack of veterinary care. Wound healing is a complex process involving inflammation, proliferation, and maturation phases, with impaired cell proliferation potentially delaying healing. Equines, including donkeys, are particularly susceptible to traumatic skin wounds, with limb wounds healing more slowly due to factors such as tissue loss, contamination, and excessive skin tension. In such cases, wound healing by second intention is common but can lead to complications. Chitosan, a biopolymer derived from the shells of crustaceans, has shown promise in promoting wound healing. It helps with tissue granulation, collagen deposition, and tissue regeneration, while also preventing wound contamination and maintaining a sterile environment. Honey, with its antimicrobial, anti-inflammatory, and antioxidant properties, is another natural remedy that accelerates wound healing and is often used in combination with chitosan for optimal results. This biologically-based approaches hold potential for improving the healing of donkey wounds and preventing infections, offering safer and more effective alternatives to traditional wound care

The Role of Self-Accumulated Peptide Amphiphile in Spinal Cord Injury Functional Reclamation

Injection into an experimentally injured spinal cord of a self-assembling peptide amphiphile (PA) that displays an IKVAV epitope reduced glial scarring and improved functional reclamation (Tysseling-Mattiace et al., 2008). Injection of a material that lacked this epitope did not alter outcome suggesting that signaling by the IKVAV epitope was central to the beneficial effects of IKVAV-PA. However the mechanical properties of implanted materials may also alter tissue and cell behavior in vivo (Discher et al., 2005). We therefore explored whether the mechanical properties of PAs might affect outcome after spinal cord injury. By treating animals with a spinal cord injury with different PAs that varied in their mechanical properties without epitope presentation, we found that the beneficial effects of the PAs are primarily dependent upon the presentation of a bioactive epitope presentation rather than the mechanical properties of the PA scaffold

A road map for reliable power electronics for more electric aircraft

The gradual evolution from hydro-pneumatic to electrical disposition of power in aircraft has placed stringent requirements on the reliability of power electronic components in current and future aerospace applications. This paper examines the prevalent state-of-the-art in power electronics and provides an analytical overview of power electronics in More Electric Aircraft (MEA) vis-à-vis the generation and distribution of power within these aircraft. The types of power devices currently employed for multiple conversion topologies are analysed and weighed according to their respective reliability characteristics. Beginning with an in-depth review of failure modes in the currently available devices, the paper highlights the salient emerging state-of-the-art Wide Band Gap (WBG) technologies such as Gallium Nitride (GaN) and Silicon Carbide (SiC) and draws an extensive comparison with their Silicon counterparts. A comprehensive examination of techniques employed for the estimation of the reliability of WBG power devices has revealed a number of areas that merit due consideration. For instance, the physics-based models that have been developed to assess the operational lifetime of silicon-based devices for given failure modes require revamping in light of the new materials and the unique electrical and physical characteristics the WBG devices possess. Similarly, the condition monitoring techniques, with respect to the primary and secondary parameters, require further investigation to determine highly representative feature vectors that best describe the degradation within these devices. More significantly, optimisation of the proposed techniques for the health assessment of these devices needs to be pursued through the optimal use of vital parameters. Keeping these critical findings in perspective, a road map highlighting various avenues for power electronics optimisation in MEA is put forth to apprise the aerospace fraternity of its growing significance

Small Integrin-Binding Ligand N-Linked Glycoproteins (Siblings): A Study On Human Salivary Gland Cancer

Salivary gland carcinomas constitute a rare but deadly group of head and neck cancers, but timely diagnosis is often delayed due to inherent variability in etiology, heterogeneity and histopathological characterization. SIBLINGs are a family of secreted glycophosphoproteins that include osteopontin (OPN), bone sialoprotein (BSP), dentin sialophosphoprotein (DSPP), dentin matrix protein-1 (DMP-1), and matrix extracellular phosphoglycoprotein (MEPE). SIBLINGs were first discovered in bone and teeth, and were considered to be exclusively expressed in mineralized tissue. In addition to mineralized tissue, SIBLINGs have now been shown to have variable expression in normal, non-mineralized tissue and in cancers. However, there have been no studies evaluating SIBLING expression in human salivary gland cancers. Our study tested the hypothesis that SIBLINGs, specifically, BSP, DSPP and OPN, would be significantly overexpressed in human salivary gland cancer. We also hypothesized that the cancer secretome would influence SIBLING expression in normal salivary gland cells. Methods: Normal and cancerous human salivary gland tissue obtained from the NDRI were processed using routine immunohistochemistry techniques to evaluate expression of BSP, DSP, and OPN. In addition normal HSG cell line and cancer HTB-41 cell line were evaluated using immunofluorescence techniques to localize expression of BSP, DSP and OPN. Normal HSG, cancer HTB-41 and HSG* cells (normal HSG cells exposed to a cancer HTB-41 secretome) were propagated using routine cell culture techniques for 24, 48, and 72 hours. Western blotting techniques were utilized ii to quantify and compare SIBLING protein expression levels in HSG, HTB-41 and HSG* cells. Normal HSG, cancer HTB-41, and HSG* cells were processed via immunoflourescence in order to observe localization of SIBLINGs. Results: Immunohistochemistry and western blot showed increased expression of SIBLINGs in human salivary gland cancers. Furthermore, immunoflourescence revealed distinct localization of SIBLING proteins in HSG and HTB-41 cell lines. In terms of HSG*, it was found that cells exposed to cancer secretome exhibited similar SIBLING expression to HTB-41. Conclusion: Our studies confirm that SIBLING proteins are selectively expressed in human salivary gland cancer. Also, the cancer secretome is found to affect SIBLING expression in normal cells, similar to HTB-41 cancer cell lines

Qualitative validation approach using digital model for the health management of electromechanical actuators

An efficient and all-inclusive health management encompassing condition-based maintenance (CBM) environment plays a pivotal role in enhancing the useful life of mission-critical systems. Leveraging high fidelity digital modelling and simulation, scalable to digital twin (DT) representation, quadruples their performance prediction and health management regime. The work presented in this paper does exactly the same for an electric braking system (EBS) of a more-electric aircraft (MEA) by developing a highly representative digital model of its electro-mechanical actuator (EMA) and integrating it with the digital model of anti-skid braking system (ABS). We have shown how, when supported with more-realistic simulation and the application of a qualitative validation approach, various fault modes (such as open circuit, circuit intermittence, and jamming) are implemented in an EMA digital model, followed by their impact assessment. Substantial performance degradation of an electric braking system is observed along with associated hazards as different fault mode scenarios are introduced into the model. With the subsequent qualitative validation of an EMA digital model, a complete performance as well as reliability profile of an EMA can be built to enable its wider deployment and safe integration with a larger number of aircraft systems to achieve environmentally friendly objectives of the aircraft industry. Most significantly, the qualitative validation provides an efficient method of identifying various fault modes in an EMA through rapid monitoring of associated sensor signals and their comparative analysis. It is envisaged that when applied as an add-on in digital twin environment, it would help enhance its CBM capability and improve the overall health management regime of electric braking systems in more-electric aircraf