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Development of an approach to automatic test generation based on the graph model of a cache hierarchy
Get PDFVerification of the cache hierarchy in modern SoCs due to the large state space requires a huge amount of complex tests. To cover the entire state space of the cache memory hierarchy graph model is proposed. The generation of tests based on this model, whose vertices (V) are the set of states (tags, values, etc.) of each cache and the edges (E) are the many transitions between states (instructions for reading, writing). Thus a graph model is constructed that describes all the states of the cache memory hierarchy. Each edge in the graph is a separate verification sequence. Vector-block operation with memory is provided. The approach described in the paper showed a good result when checking the hierarchy of the multiport cache memory of the developed kernel with the new vector VLIW DSP architecture, revealing several architectural and functional errors. Further, this approach will be applied to test other processor cores and their blocks
Addressing Avoidable Inequalities: The Role of One University in Place-Based Transformational Change
Get PDFThis chapter explores one UK university’s influence and involvement as a key partner within the 2025 Movement, a movement for change with a collective vision to tackle avoidable health and housing inequalities by 2025 in North Wales, UK. The approach to building 2025 is founded in systems leadership and social movements resulting in transformational change in the way we work, think and deliver across a region as a collective. The innovative role of the university as a key partner has shifted the perceptions of the university in the region and its capacity to act as an instrument of government, contributing to the political imperative to support communities as part of the Well-being of Future Generations (Wales) Act 2015. The chapter outlines the principles behind 2025 and the university’s role to date, as illustrated through three case studies: Learning and Leadership; Social Prescribing; and Healthy Homes–Healthy People. The chapter reflects upon the challenges faced and how they have been overcome. Finally, enablers for successful collective working are identified, which have resulted in the university being able to utilize its expertise, energy and education to work in partnership in order to tackle some of the most complex issues facing our communities
Pectins from food waste: Characterization and functional properties of a pectin extracted from broccoli stalk
Get PDFCurrently about 60–75% of world broccoli production is wasted during harvesting. The aim of the present study was to extract and characterise the pectin present in broccoli stalks and to evaluate its functional properties. The stalks were initially treated with boiling ethanol to remove compounds such as pigments and free sugars and then the pectin (FB) was extracted with 0.1 M nitric acid for 30min. The pectic fraction FB (18% yield) was found to contain 75% galacturonic acid with a degree of methyl-esterification of 56%, and an acetyl content of 1.1%. Rhamnose and galactose were the main neutral sugars present. NMR analyses showed that FB was composed of homogalacturonan and rhamnogalacturonan I substituted with β-1,4-D-galactan. The molar mass of FB was 72.2 × 103 g/mol and the viscosity of a 5% (w/w) solution in 0.1M NaCl at pH 4 showed shear thinning behaviour with a low shear Newtonian plateau of ~100 Pa s at 25 °C. At the same concentration FB showed a weak gel like behaviour. FB (0.5–4%, w/w) was also able to stabilize medium chain triglyceride oil in water emulsions. The results suggest that broccoli stalk could be used as an alternative source of commercial pectins
A Comprehensive Survey of “Metamaterial Transmission-Line Based Antennas: Design, Challenges, and Applications”
Get PDFIn this review paper, a comprehensive study on the concept, theory, and applications of composite right/left-handed transmission lines (CRLH-TLs) by considering their use in antenna system designs have been provided. It is shown that CRLH-TLs with negative permittivity (ε <; 0) and negative permeability (μ <; 0) have unique properties that do not occur naturally. Therefore, they are referred to as artificial structures called “metamaterials”. These artificial structures include series left-handed (LH) capacitances (C L ), shunt LH inductances (L L ), series right-handed (RH) inductances (LR), and shunt RH capacitances (CR) that are realized by slots or interdigital capacitors, stubs or via-holes, unwanted current flowing on the surface, and gap distance between the surface and ground-plane, respectively. In the most cases, it is also shown that structures based on CRLH metamaterial-TLs are superior than their conventional alternatives, since they have smaller dimensions, lower-profile, wider bandwidth, better radiation patterns, higher gain and efficiency, which make them easier and more cost-effective to manufacture and mass produce. Hence, a broad range of metamaterial-based design possibilities are introduced to highlight the improvement of the performance parameters that are rare and not often discussed in available literature. Therefore, this survey provides a wide overview of key early-stage concepts of metematerial-based designs as a thorough reference for specialist antennas and microwave circuits designers. To analyze the critical features of metamaterial theory and concept, several examples are used. Comparisons on the basis of physical size, bandwidth, materials, gain, efficiency, and radiation patterns are made for all the examples that are based on CRLH metamaterialTLs. As revealed in all the metematerial design examples, foot-print area decrement is an important issue of study that have a strong impact for the enlargement of the next generation wireless communication systems
Machine Learning-assisted Antenna Design optimization: A Review and the State-of-the-art
Get PDFAntenna design optimization continues to attract a lot of interest. This is mainly because traditional antenna design methodologies are exhaustive and have no guarantee of yielding successful outcomes due to the complexity of contemporary antennas in terms of topology and performance requirements. Though design automation via optimization complements conventional antenna design approaches, antenna design optimization still presents a number of challenges. The major challenges in antenna design optimization include the efficiency and optimization capability of available methods to address a broad scope of antenna design problems considering the growing stringent specifications of modern antennas. This paper presents a review of the most recent progress in antenna design optimization with a focus on methods which address the challenges of efficiency and optimization capability via machine learning techniques. The methods highlighted in this paper will likely have an impact on the future development of antennas for a multiplicity of applications
Design and Analysis of Compact Antenna for 5G Communication Devices
Get PDFA novel slotted rectangular patch antenna for E and W band, which resonates at the frequency of 67 GHz and has impedance bandwidth of 13.2 GHz, is used for resolving the issues of compactness, gain and efficiency of antenna designs for future generation 5G devices such as watches, and dongles. The single element antenna, having a dimension of 5.5 × 4.7 × 0.381 mm3, with a realized gain of 8.9 dBi was achieved. A rectangular slot was placed in the ground plane, just under the feed line of a microstrip patch antenna (MSPA), and this works as a defected ground structure (DGS): this improved the gain by up to 2 dB in the proposed design. The partial ground is used for tuning the impedance bandwidth. The rationale for the DGS, the partial ground, and the effect of the slot technique are discussed and implemented in this paper
A writing aid for dysgraphia affected people
Get PDFDysgraphia is a writing disability due to ineffective working of motor neurons, causing the patient to face difficulty in writing. Many studies have been done to overcome Dysgraphia but unfortunately, only therapies are made instead of any aid. In this paper, a movement aid is proposed that removes the need of any therapy. The proposed methodology comprises of acquisition of hand movement signal from Motor Cortex and Sensory Brain area by using EEG scanning. These signals are then processed using Brain Computer Interface (BCI2000), which mainly includes Features selection, extraction and translational algorithms to convert signals into commands. These commands are then used to control Hand Movement device. The Hand Movement device uses the FES, applied at the forearm to perform different hand movements. This paper focuses on the flexion and extension of the fist
The influence of pH and monovalent ions on the gelation of pectin from the fruit seeds of the creeping fig plant
Get PDFPectin from the fruit seeds of the creeping fig plant was extracted and its chemical composition and rheological properties determined. It was found to consist of ~87% galacturonic acid with a degree of methoxylation of ~20%. The polysaccharide produced a viscous solution at pH 4.5 and was shown to form strong gels when the pH was reduced by the addition of glucono-delta lactone. It was concluded that as the pH was lowered, the reduction in electrostatic repulsions between the pectin chains facilitated chain association mainly through hydrogen bonding. The rate of gelation increased considerably as the pH was reduced. Although the pectin was in the form of a solution at pH 4.5, the addition of Na+ and K+ salts resulted in gel formation. The strength of the gels was found to be dependent on both the concentration and nature of the added electrolyte in accordance with the Lyotropic series. It has been suggested that the role of the electrolyte was to reduce the electrostatic repulsions between the carboxylate groups along the pectin chains thus facilitating chain association. Association is promoted by the presence of a low concentration of Ca2+ ions (1.88% w/w) naturally present in the extracted material which facilitated the crosslinking of the pectin chains in addition to the association through hydrogen bonding
Factors influencing routine cognitive impairment screening in older at‐risk drinkers: Findings from a qualitative study in the United Kingdom
Get PDFCognitive Impairment (CI) screening is recommended for those engaged in harmful levels of alcohol use. However, there is a lack of evidence on implementation. This paper explores the barriers and facilitators to CI screening experienced across a service specifically for older drinkers. The findings draw on data gathered as part of an evaluation of a multilevel programme to reduce alcohol‐related harm in adults aged 50 and over in five demonstration areas across the United Kingdom. It is based on qualitative interviews and focus groups with 14 service providers and 22 service users. Findings are presented thematically under the section headings: acceptability of screening, interpretation and making sense of screening and treatment options. It is suggested that engagement with CI screening is most likely when its fit with agency culture and its purpose is clear; where service providers have the technical skills to administer and discuss the results of screening with service users; and where those undertaking screening have had the opportunity to reflect on their own experience of being screened. Engagement with CI screening is also most likely where specific intervention pathways and engagement practices can be accessed to respond to assessed need
Online magnetization surface identification for a switched reluctance motor
Get PDFThe precise control of switched reluctance motor requires information about the magnetization surface as a function of rotor angular position and current. The surface can be obtained performing offline tests; however, it demands specialized mechanical equipment and time for commissioning. Moreover, the magnetization surface may be changed with the varying of the rotor and stator temperatures, which affect their dimensions and, therefore, the airgap variation. That is why the online estimation of the magnetization surface is desirable. This paper proposes the identification method operating in parallel with the model predictive current control system utilizing the magnetization map. Any error between the referenced and obtained currents is used to correct the reference points of the two-dimensional array representing the magnetization surface. The proposed method was examined using a simulation model and operated online in parallel with the primary control system driving the electrical machine