Baseness in Thiruvalluvar's vision

Man observes everything while participating in the social movement in which he lives. Good works appear when he begins to express what he has observed aesthetically and virtuously. Thirukkural is a great work that has appeared in this way. Thiruvalluvar has given 1330 Thirukkural to the world through 133 chapters. He was the one who conveyed great news to the people through the small steps of Thirukkural. There is nothing in Thirukkural that is not spoken. There is nothing in the world that he does not say. Thirukkural has such a distinction. That is why its creator Thiruvalluvar is called the great sage who has realized all the time. This is the way Thirukkural is to convey the trilogy

ENERGY-EFFICIENT AND SECURE HARDWARE FOR INTERNET OF THINGS (IoT) DEVICES

Internet of Things (IoT) is a network of devices that are connected through the Internet to exchange the data for intelligent applications. Though IoT devices provide several advantages to improve the quality of life, they also present challenges related to security. The security issues related to IoT devices include leakage of information through Differential Power Analysis (DPA) based side channel attacks, authentication, piracy, etc. DPA is a type of side-channel attack where the attacker monitors the power consumption of the device to guess the secret key stored in it. There are several countermeasures to overcome DPA attacks. However, most of the existing countermeasures consume high power which makes them not suitable to implement in power constraint devices. IoT devices are battery operated, hence it is important to investigate the methods to design energy-efficient and secure IoT devices not susceptible to DPA attacks. In this research, we have explored the usefulness of a novel computing platform called adiabatic logic, low-leakage FinFET devices and Magnetic Tunnel Junction (MTJ) Logic-in-Memory (LiM) architecture to design energy-efficient and DPA secure hardware. Further, we have also explored the usefulness of adiabatic logic in the design of energy-efficient and reliable Physically Unclonable Function (PUF) circuits to overcome the authentication and piracy issues in IoT devices. Adiabatic logic is a low-power circuit design technique to design energy-efficient hardware. Adiabatic logic has reduced dynamic switching energy loss due to the recycling of charge to the power clock. As the first contribution of this dissertation, we have proposed a novel DPA-resistant adiabatic logic family called Energy-Efficient Secure Positive Feedback Adiabatic Logic (EE-SPFAL). EE-SPFAL based circuits are energy-efficient compared to the conventional CMOS based design because of recycling the charge after every clock cycle. Further, EE-SPFAL based circuits consume uniform power irrespective of input data transition which makes them resilience against DPA attacks. Scaling of CMOS transistors have served the industry for more than 50 years in providing integrated circuits that are denser, and cheaper along with its high performance, and low power. However, scaling of the transistors leads to increase in leakage current. Increase in leakage current reduces the energy-efficiency of the computing circuits,and increases their vulnerability to DPA attack. Hence, it is important to investigate the crypto circuits in low leakage devices such as FinFET to make them energy-efficient and DPA resistant. In this dissertation, we have proposed a novel FinFET based Secure Adiabatic Logic (FinSAL) family. FinSAL based designs utilize the low-leakage FinFET device along with adiabatic logic principles to improve energy-efficiency along with its resistance against DPA attack. Recently, Magnetic Tunnel Junction (MTJ)/CMOS based Logic-in-Memory (LiM) circuits have been explored to design low-power non-volatile hardware. Some of the advantages of MTJ device include non-volatility, near-zero leakage power, high integration density and easy compatibility with CMOS devices. However, the differences in power consumption between the switching of MTJ devices increase the vulnerability of Differential Power Analysis (DPA) based side-channel attack. Further, the MTJ/CMOS hybrid logic circuits which require frequent switching of MTJs are not very energy-efficient due to the significant energy required to switch the MTJ devices. In the third contribution of this dissertation, we have investigated a novel approach of building cryptographic hardware in MTJ/CMOS circuits using Look-Up Table (LUT) based method where the data stored in MTJs are constant during the entire encryption/decryption operation. Currently, high supply voltage is required in both writing and sensing operations of hybrid MTJ/CMOS based LiM circuits which consumes a considerable amount of energy. In order to meet the power budget in low-power devices, it is important to investigate the novel design techniques to design ultra-low-power MTJ/CMOS circuits. In the fourth contribution of this dissertation, we have proposed a novel energy-efficient Secure MTJ/CMOS Logic (SMCL) family. The proposed SMCL logic family consumes uniform power irrespective of data transition in MTJ and more energy-efficient compared to the state-of-art MTJ/ CMOS designs by using charge sharing technique. The other important contribution of this dissertation is the design of reliable Physical Unclonable Function (PUF). Physically Unclonable Function (PUF) are circuits which are used to generate secret keys to avoid the piracy and device authentication problems. However, existing PUFs consume high power and they suffer from the problem of generating unreliable bits. This dissertation have addressed this issue in PUFs by designing a novel adiabatic logic based PUF. The time ramp voltages in adiabatic PUF is utilized to improve the reliability of the PUF along with its energy-efficiency. Reliability of the adiabatic logic based PUF proposed in this dissertation is tested through simulation based temperature variations and supply voltage variations

Rheology of Cement Mixed with Hollow Microspheres

Hollow microspheres cement is lightweight cement solution that is designed to have the highest strength ratio and lowest permeability of any cement design at a given slurry density, and rapid compressive strength to reduce Wait on Cement (WOC). Hollow microspheres used to reduce hydrostatic pressure on weak formations and to cement lost circulation zones. Hollow microspheres are produced from a mixture of liquid sodium silicate glass and a foaming agent [2]. For example, carbonates, bicarbonates, sulphates, nitrates, and acids are used as foaming agent. The mass is then dried and crushed. In this study, the focuses are mainly cementing the intermediate and production casing in a single stage using low density cement that was based on hollow microspheres. The objectives of this work is to analysis low density cement in High Pressure High Temperature (HPHT) formation which also includes the lab tests such compressive strength, fluid loss and thickening time test. Hollow microspheres cement is a High Strength, Low Density (HSLD) cement system which suggested for increasing primary cementing success in steam injected, low fracture gradient areas. It is incompressible cement which provides consistent and predictable density from the top of the borehole to the bottom. The hollow microsphere cement system is HSLD acknowledged as a feasible solution because conventional cement designs lose the formation. Advantages of using hollow microspheres cement are that it gives an excellent mud displacement, enhanced mechanical properties, good strength to density ratio and long lasting zonal isolation. A programme is developed using software to test the parameters such as temperature, pressure and density of the cement. Although the microspheres operations can be very complex, hollow microspheres cement has many applications that can justify the increase complexity. Cement slurry using hollow microspheres can be applied in high permeability formations, poorly consolidated formations and HPHT formations

OPTIMIZATION OF FORMULATION OF FLOATING HYDROGELS CONTAINING GAS FORMING AGENT USING RESPONSE SURFACE METHODOLOGY

Objective: The objective of present study was to determine the optimum gas forming agent concentration to enhance the floating ability and drug release pattern of floating hydrogels by using factorial design. Methods: In this article calcium carbonates as gas forming agents was synthesized in modified floating kappa carrageenan hydrogels. Ranitidine Hydrochloride was used as drug. 32 full factorial design was utilized for the optimization of gas forming agents. Polymer ratio (X1) and calcium carbonates concentration (X2) were used as independent variables. The floating hydrogels were characterized and the results obtained are swelling ratio study, drug entrapment efficiency, floating lag time and cumulative drug release. Results: From the factorial batches, it was observed that formulation containing 0.5% of calcium carbonates with 80:20 ƙC: NaCMC showed the optimum floating properties, swelling ratio, drug entrapment efficiency and cumulative drug release. Conclusion: Thus, formulation containing 0.5% of calcium carbonates with 80:20 ƙC:NaCMC appear to be a potential approach to develop sustains drug release in gastrointestinal condition

Bis(3-benzoyl-1,1-di-sec-butyl­thio­ureato-κ2 O,S)palladium(II)

The complex mol­ecule of the title complex, [Pd(C16H23N2OS)2], is completed by crystallographic twofold symmetry with the metal atom lying on the rotation axis. The PdII atom exists within a slightly distorted square-planar geometry defined by a cis-O2S2 donor set. The dihedral angle formed between the mean planes of the symmetry-related six-membered chelate rings is 12.88 (7)° and the bond lengths within the rings are indicative of significant electron delocalization. In the crystal, mol­ecules aggregate into dimers linked by four C—H⋯O inter­actions

Bioaffinity separation using ligand-modified pluronic and synthetic membranes

Thesis (PhD)--University of Stellenbosch, 2005.ENGLISH ABSTRACT: A new membrane based affinity separation system that is bio-specific, biocompatible, well characterised and capable of being regenerated or re-used is described. The amphiphilic non-ionic surfactant Pluronic® F108, was covalently derivatised to form two novel bioligands (Pluronic-Biotin and Pluronic-DMDDO) for the bio-specific immobilisation of avidin conjugated proteins and histidine tagged proteins respectively. Pluronic was also used to non-covalently functionalise nonporous membranes for ligand attachment and to simultaneously shield the surfaces from non-specific protein adsorption. Each component of this bioaffinity system (from the membrane matrix to the elution/desorption of the ligate/ligand system) was studied with the aim of producing a well characterised system and key quantitative data for the development of a robust, reliable, re-usable and scalable technology. Specifically, this study describes: 1. The fabrication and partial characterisation of nonporous planar and capillary membranes as model affinity matrices. 2. The development and evaluation of a robust protocol for solvent desorption and accurate colorimetric quantification of Pluronic® F108 and its derivatives. 3. Interfacial analysis of Pluronic adsorption onto nonporous affinity membranes, including the direct solid-state analysis of model, halogenated Pluronic derivatives using nuclear microprobe analysis. 4. Development of a surfactant based protocol for affinity membrane regeneration and re-use. 5. Specific bioaffinity immobilisation of avidin conjugated peroxidase onto biotinylated membranes in the presence of model protein foulants. 6. Cloning and expression of C-terminal hex-histidine tagged human cytochrome b5 into the bacterial expression system E. coli BL-21 DE3. 7. Development and characterisation of an immobilised metal affinity membrane system for metal chelation (Ni2+, Cu2+ and Zn2+) using a new chelator Pluronic- N,N-dicarboxymethyl-3,6-diazaoctanedioate and the bio-specific immobilisation of N-terminal hex-histidine tagged pantothenate kinase.AFRIKAANSE OPSOMMING: 'n Nuwe membraan-gebaseerde affiniteitskeidingsisteem word beskryf wat biospesifiek, bioversoenbaar en goed gekarakteriseer is, en geregenereer of hergebruik kan word. Die amfifiliese nie-ioniese surfaktant Pluronic is kovalent gederivatiseer om twee nuwe bioligande (Pluronic-Biotien en Pluronic-DMDDO) te vorm vir biospesifieke immobilisering van proteïnligate. Pluronic is ook gebruik om nie-poreuse membrane niekovalent te funksionaliseer vir ligandaanhegting en om hulle oppervlaktes teen niespesifieke proteïen-adsorbsie af te skerm. Elke komponent van hierdie bioaffiniteitsisteem (van die membraanmatriks tot die uitwas/desorpsie van die ligaat/ligand sisteem) is ondersoek met die doel om 'n goed-gekarakteriseerde sisteem te produseer en om kwantitatiewe data te genereer vir die ontwikkeling van 'n robuuste, betroubare, herbruikbare en opskaleerbare tegnologie. Hierdie studie beskryf spesifiek: 1. Die fabrisering en gedeeltelike karakterisering van nie-poreuse planêre en kapillêre membrane as model affiniteitsmatrikse. 2. Die ontwikkeling en evaluering van 'n robuuste protokol vir oplosmiddel desorpsie en akkurate kolorimetriese kwantifikasie van Pluronic® F108 en afgeleides daarvan. 3. Intervlakanalises van Pluronic adsorpsie op nie-poreuse affiniteitsmembrane, insluitend die direkte vastetoestand analise van model ligand-gemodifiseerde Pluronic deur die gebruik van kern-mikrosonde analise. 4. Ontwikkeling van 'n surfaktant-gebaseerde protokol vir affiniteitsmembraan regenerering en hergebruik. 5. Spesifieke bioaffiniteitsimmobilisering van avidien-gekonjugeerde peroksidase op gebiotinileerde membrane in die teenwoordigheid van model bevuilende proteïne. 6. Klonering en uitdrukking van C-terminaal hex-histidien geëtiketeerde menslike sitochroom b5 in die bakteriële uitdrukkingsisteem E. coli BL-21 DE3. 7. Ontwikkeling en karakterisering van 'n geïmmobiliseerde metaalaffiniteitsmembraansisteem vir metaalchelering (Ni2+, Cu2+ en Zn2+) met behulp van die nuwe cheleerder Pluronic-N,N-dikarboksimetiel-3,6- diasaoktaandioaat en die bio-spesifieke immobilisering van N-terminaal hexhistidiengeëtiketerde pantotenaatkinase

Interferometric Synthetic Aperture Radar for remote satellite monitoring of bridges

The structural health of critical infrastructure is difficult to assess and monitor with existing methods of evaluation which rely predominantly on visual inspection and/or the installation of sensors to measure the in-situ performance of structures. There are vast numbers of critical structures that need to be monitored and these are often located in diverse geographical locations which are difficult and costly to access. Recent advances in satellite technologies provide the opportunity for global coverage of assets and the measurement of displacement to sub-centimetre accuracy. Such measurements could supplement existing monitoring techniques and provide asset owners with additional insights which could inform operational and maintenance decisions. Most past research within the field of Interferometric Synthetic Aperture Radar (InSAR) monitoring using satellite radar imagery focusses on widespread measurement of land areas, although there have been some case studies using InSAR to assess movements of individual structures such as dams. However, there is limited published research into the use of these techniques for accurately monitoring the displacements of individual civil engineering structures over time and relating these measurements to structural performance. This research focusses on bridges as a specific example of critical infrastructure to establish whether remote satellite monitoring can be used to measure displacements at a resolution that is sufficiently accurate for use in monitoring of performance, and examines the relevance and limitations of satellite monitoring to civil engineering applications in general. In order to assess the millimetre-scale performance of InSAR, an initial evaluation was undertaken in controlled conditions on a purpose-built test bed fitted with satellite reflectors at the National Physical Laboratory in Teddington to validate InSAR displacement measurements against traditional terrestrial in-situ displacement measurements. Subsequently, traditional sensor and surveying measurements of displacements were compared with InSAR displacement measurements at key points of interest on Waterloo Bridge and the Hammersmith Flyover. A further case study on Tadcaster Bridge was undertaken to demonstrate the potential applicability of InSAR displacement measuring techniques for monitoring bridges at risk of scour failure. Scour is the most common form of bridge collapse around the world and to date no cost-effective and widely applicable method for providing advanced warning of impending failure due to scour has been developed. Methodologies for integrating digital, structural and signal processing models for the identification and mapping of InSAR measurement points on bridge structures from SAR imagery were developed, as well as methodologies for combining satellite data with traditional surveying methods. An important outcome of this research was that through comparison of independent measurements, InSAR measurements are of a scale that is applicable to bridge monitoring. Remote sensing can therefore reach global coverage, with unsupervised readings over an interval of days, and as such supplement traditional inspection regimes. However, this outcome must be presented with several limitations. Practical implications of applying InSAR to real bridges are discussed, including imaging effects and the suitability of monitoring different forms of bridge deformation. The key to successful implementation of InSAR monitoring of bridges lies in understanding the limitations and opportunities of InSAR, and making a clear case to satellite data providers on what specifications (resolution, frequency, processing assumptions) would unlock using such datasets for wider use in monitoring of infrastructure. InSAR can provide measurements and useful insights for bridge monitoring but it is limited to specific cases and, at this stage of technological development, it should be considered as a tool for specific bridges and failure mechanisms rather than a full bridge monitoring solution.This PhD was funded by the Engineering and Physical Sciences Research Council (EPSRC), U.K., under Award 1636878 with iCASE sponsorship by the National Physical Laboratory. Further funding contributions were provided by Laing O’Rourke. Projects within the PhD received funding from Innovate UK and some of the data was provided by the German Aerospace Centre (DLR) under proposal MTH3513

The impact of workplace bullying on employees’ wellbeing in an organization

Workplace bullying (WPB) is on the emergence, and it is both unlawful and undermines employees' rights. Intense workplace bullying can result in violence and violent abuse, although the most common occurrences are unpleasant motions and verbal abuse such as ominous glares, warning, yelling at the employee, refusing to connect vocally or electronically, and terminating the employee. It exists in companies and manifests in a variety of ways, causing mental stress, inefficiency, the loss of skilled resources, and injury to the targeted individual's self-esteem. It is critical for employers to catch workplace bullies early on in order to create a healthy workplace environment. Previous study has examined what bullying is and its effects, taking all of these factors into consideration. The objective of this study is to examine the relationship between bullying (verbal bullying, non-verbal bullying, psychological bullying, and physical bullying) and employee wellbeing in an organization. Data was collected by using the questionnaire that has been distributed to the respondents who mainly the employees working in organizations. The results indicated a significant relationship between the independent variables (verbal, nonverbal, psychological and physical) and the dependent variable (employee wellbeing). This study demonstrates that bullying can take different forms, such as psychological, verbal, non-verbal and physical. It is collective responsibility within an organization to ensure that proper systems and strategies are adopted to ensure employee wellbeing is upheld by eliminating or reducing bullying behaviours in the workplace. Overall, this thesis study provides a comprehensive perspective on the topic of workplace bullying and the well-being of employees in an organization in a different approach in ways of methods, findings, implications and significance

Majorization for a Class of Analytic Functions Defined by q

We introduce a new class of multivalent analytic functions defined by using q-differentiation and fractional q-calculus operators. Further, we investigate majorization properties for functions belonging to this class. Also, we point out some new and known consequences of our main result