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This study aims to develop a multidisciplinary artificial hybrid machine learning (AHML) approach to reduce the scanning time (ST) of the human wrist and improve the accuracy of 3D scanning for anthropometric data collection. A systematic AHML approach was deployed to scan the human wrist distal end optimally using a portable SENSE 2.0 3D scanner. A central composite design (CCD) matrix was developed for three input variables; light intensity (LI = 12–20 W/m2), capture angle (CA = 10°–50°), and scanning distance (SD = 10–20 inches) for executing the experimental runs. For accuracy evaluation, the wrist perimeter on the distal end was checked using CREO Parametric software for wrist perimeter error (WPE). Various AHML tools were developed using: response surface methodology (RSM), multi-objective genetic algorithm RSM, and multi-objective genetic algorithm neural networking (MOGANN). The optimal process parameters recommended by the hybrid tools were experimentally validated for their prediction accuracy. The MOGANN approach combined with the Bayesian regularization algorithm (trainabr) provided the best mutual combination of optimal ST = 20.072 sec and WPE = 0.375 cm corresponding to LI = 12.001 W/m2, CA = 29.428°, and SD = 18.214 inch, with a significant percentage reduction of 55.83% in WPE. Executing 3D scanning of the human wrist over the optimized process parameters predicted by AHML tools will ensure the availability of precise scans for the rapid prototyping of customized orthotic devices in a reliable manner.
Normally, the reported gain of the microstrip patch antenna is within 8 dBi. Using properly located three shorting pins on three bisectors, the present work reports a method to convert the non-radiating TM11 mode of equilateral triangular patch antennas (ETPAs) to a deformed TM11 radiating mode. The boresight gain of ETPA operating in TM11 mode is enhanced from −10.75 to 12.1 dBi at 5.43 GHz. The boresight measured gain is further enhanced to 14.2 dBi at 5.52 GHz by using a triangular surface-mounted short horn (SMSH) of about ${{\lambda }}/5$ height. The aperture efficiency of the ETPA with the shorting pins is 84.2%. The aperture efficiency is further improved to 94.2% using the SMSH. The measured boresight cross-polarization and side-lobe level are −40 and −29 dB, respectively. The nature of the electricfield and surface current distribution is analyzed, using both the characteristic mode analysis method and high-frequency structure simulator, to understand the role of shorting pin and coaxial feed in converting the non-radiating TM11 mode to the radiating mode. A systematic design process also is presented for a fast design of shorting pin-loaded ETPA on the suitable substrate at a specified frequency.
The purpose of the study was to design, develop, and validate a newer tool on radiation emergency preparedness responses (RadEM-PREM IPE tool) to measure communication, knowledge, performance skills in multidisciplinary health science learners.
Methods:
The study design is a prospective, single centric, pilot study. Five subject experts designed, analyzed, and selected items of the instrument for relevant content and domain. Psychometrics that the tool assessed were content validity, internal consistency, test-retest reliability, and intraclass correlation coefficient. Twenty-eight participants completed test-retest reliability for validation of 21 sorted out items calculated percentage of agreement >70% I-CVI/UA (item content validity index with universal acceptability) and S-CVI/UA (scale content validity index with universal agreement method).
Results:
Items with percentage agreement >70% and I-CVI over 0.80 were kept, ranged from 0.70 to 0.78 were revised, and below 0.70 were rejected. Items with kappa values ranging from 0.04 to 0.59 were revised and ≥0.74 were retained. Internal consistency assessed using Cronbach’s alpha was 0.449. Positive correlation between attitude and communication (r = 0.448), between performance and communication (r = 0.443) were statistically significant at 0.01 level. Overall, intraclass correlation coefficient for all the measures is 0.646, which is statistically significant at 0.05 level (P < 0.05).
Conclusions:
Study concludes that the RadEM-PREM IPE tool would be a new measuring tool to assess knowledge, performance, and communication skills of interprofessional radiation emergency response team learner’s evaluation.
In this paper, a compact super wideband annular ring antenna using 45° clock-wise square patch inclusions for super high frequency and polarization diversity applications is proposed. The inclusions consist of a combination of squares and circles into one another in the inner area of a main annular ring radiator. The antenna uses a partial ground plane having a stair-type defected ground structure, is designed on an FR-4 substrate, and has a total size of 25 × 26 × 1.6 mm3 (0.17λ × 0.18λ). The design was fabricated and experimental results fairly agreed with simulations and resulted in an antenna with an operating frequency from 2.07 to 30 GHz; that is, a large fractional bandwidth of 174.2$\%$ with a bandwidth (BW) ratio of 14.5:1 and a high BW dimension ratio, BW per unit electrical length of 5693, and a measured peak gain of 8 dBi with an average gain of 5 dBi for the overall operating frequency. For the polarization diversity, a 4 × 4 multiple input-multiple output configuration is additionally presented, offering an effective isolation of ≥ 22.5 dB between ports and corroborated by measurements.
Lead sulfide (PbS) is having tremendous applications in the field of optoelectronics. Hence, a facile low temperature synthesis of PbS with different contents of terbium (Tb) has been achieved and investigated for structure–optic–dielectric–electrical properties. The structure confirmation was observed through the X-ray diffraction and Rietveld refinement process which approved a monophasic cubic structure. Rietveld refinement gives a best-fitting profile of the prepared products. The crystallite size was estimated to be in range of 15–21 nm. FT-Raman study also approved the single-phase PbS with all characteristic modes. For further confirmation of composition, homogeneity, and Tb in the final product, the EDX/SEM e-mapping was carried out. The morphological investigation was carried out through SEM which revealed that the shape and size are greatly influenced by Tb content addition in PbS. The energy gap (Eg) was estimated in the range of 1.42–1.62 eV for all Tb@PbS, and the largest Eg value was observed for 0.5 wt% Tb@PbS. The dielectric constant values are calculated in the range of 16–25 in the tested frequency region. The ac electrical conductivity was enhanced with frequency, and a charge transport mechanism is related to a correlated barrier hoping model in the prepared samples.
The present work describes a unique planar low-profile wideband circularly polarized Multiple-Input and Multiple-Output (MIMO) antenna operating in the X-band, with pattern and polarization diversity over the entire axial-ratio bandwidth (ARBW). The design is unique in the sense that a simple grounded stub introduced between two linearly polarized monopole antennas has been used to realize wideband circular polarization, pattern diversity, and high isolation between antennas. The ARBW of the MIMO antenna is 2.45 GHz (8.11–10.56) 3 dB and its impedance matching bandwidth is 3.52 GHz (8.07–11.59). The isolation is better than 20 dB. The antenna can be easily adapted to operate other frequency bands by simple frequency scaling. It has been fabricated on an FR-4 substrate and its performance has been compared against several existing available antennas.
Mechanical properties of Pr (praseodymium)-doped ZnO thin films, deposited on a corning glass substrate and fused quartz at different deposition pressures using DC sputtering were investigated. Crystalline growth in Pr-doped ZnO thin films is more pronounced and improves at 10 mtorr deposition pressure. However, lower sputtering deposition pressure evoked deposition rates to the formation of polycrystalline films emerged in several crystal planes. Pr ions incorporated in the ZnO host lattice was examined by X-ray photoelectron spectroscopy (XPS), AFM, and FESEM. XPS spectroscopy revealed the presence of Pr3+ and Pr4+ at the ZnO surface layer and it was in tandem with EDS mapping. Nanoindentation prior to scratch testing is used for analyzing deformation characteristics. Pr-doped ZnO thin films exhibit better hardness (9.89 ± 0.14 GPa) and Young’s modulus (112.12 ± 3.45 GPa) on the glass substrate. The crack propagation resistance parameter of the films was evaluated using initial critical load, Lc1 ∼ 2250.5 µN for the crack initiation and upper critical load Lc2 ∼ 2754.5 µN for film failure. Better crack propagation resistance was observed for films deposited at 10 mtorr sputtering pressure on both substrates, attributed to better crystalline nature of the films.
Light collection efficiency and specific molecular detection are crucial factors for the performance of bio-chemical molecule sensors. In this paper, the low optical-reflection silicon (Si) substrates which combine reduced optical reflectivity by light trapping effect and high Raman enhancement ability of gold nanoparticles (Au-NPs) coated textured Si substrates are investigated for surface-enhanced Raman scattering (SERS). A fast, single-step and highly controllable nanosecond (ns) laser processing technique is employed to fabricate textured Si substrates under ambient conditions. Parallel arrays of micro-pyramids are fabricated on Si surface by direct laser writing two-dimensional structures. SEM micrographs clearly show well-ordered surface features in the form of micro-pyramid shape with well-defined sharp tips on the laser processed Si substrates. The aggregation of Si micro/nanoparticles on Si surface forms nanocavities and nanogaps and further enhances the surface roughness in order to minimize the optical reflection. The low optical reflection Si substrates exhibit optical reflection below 15% over a broad wavelength range from 300 nm to 1200 nm. The textured Si substrates with high signal reproducibility are successfully applied as SERS substrates to detect a very small concentration of Rhodamine B molecules with an average enhancement factor of the order of ∼107. The low optical reflection and SERS signal amplification are also altered by the variation of laser pulse energy resulting into low optical reflection and high SERS signal intensity over the entire laser-patterned area. The effect of surface roughness on water contact angle was studied after the modification with Polydimethylsiloxane (PDMS), the surfaces show perfect superhydrophobicity with almost no water adhesion. This approach provides a novel high-speed and cost-effective method for fabricating SERS substrate with micro/nano-scale surfaces roughness and low optical reflection for high Raman signal enhancement.
Synthesis of differential-mode bandpass filter (BPF) with good common-mode suppression has been described and demonstrated on the basis of ring dielectric resonator (RDR) for high-performance communication system. A RDR with two pairs of feeding lines has been used to excite TE01δ-mode. This unique combination of feeding lines and the ring resonator creates a differential passband. Meanwhile, TM01δ-mode of the DR can also be excited to achieve common-mode rejection in the stopband. Transmission zeros are created in the lower and upper stopband to further improve the selectivity of the proposed BPF. A second-order differential BPF is designed, fabricated and its performance is measured to validate the concept. There is good agreement between simulated and measured results.
Man Mohan, Emeritus Professor, Department of Physics and Astrophysics, University of Delhi, Delhi,Anil Kumar Maini, Former Director, Laser Science and Technology Centre, Delhi,Aranya B. Bhattacherjee, Associate Professor, Department of Physics, ARSD College, University of Delhi, Delhi
COIL is a chemical laser in which the required pumping energy for population inversion is released via a chemical reaction. This property makes the COIL attractive for defence application because it eliminates the need for electrical power supply at remote locations. Among other chemical lasers, COIL has the advantages of power scalability, short wavelength (1.315 μm) compatible with fiber (Grunewald et al.) for remote operation and also better laser material interaction.
In COIL, a gas−liquid phase reaction between basic hydrogen peroxide and chlorine gas at sub-atmospheric pressure (Azyazov et al.) produces the pumping source, singlet oxygen. This is diluted with sufficient nitrogen buffer gas to reduce the various loss mechanisms. Part of the pump energy contained in the singlet oxygen is used in the dissociation of iodine molecules into iodine atoms and the rest is used to excite these iodine atoms by near resonant energy transfer reaction. The interaction of singlet oxygen with atomic iodine at appropriate flow conditions results in the generation of laser gain medium inside the laser cavity from where the laser output power is extracted using an optical resonator.
To develop a high power COIL, it is important to study the gain characteristics, i.e., the small signal gain and the saturation intensity of the active medium under different flow conditions and to evaluate the optimum cavity coupling for achieving maximum output power. In this chapter, different COIL input parameters required for optimal gain medium formation in the laser cavity have been analyzed and gain characteristics using simplified saturation model (SSM) (Hager et al.) for the development of high power COIL have been estimated. The resonator parameters and output mirror coupling are evaluated keeping in view the resonator stability, diffraction loss, utilization of mode volume and laser beam divergence. On the basis of these parameters, the laser cavity and optical resonator for high power COIL have been developed and tested.
Power Shifts and Global Governance: Challenges from South and North explores changing architectures of global governance in the midst of great power shifts in the twenty-first century.
Mycobacterium tuberculosis (Mtb) is a metabolically flexible pathogen that has the extraordinary ability to sense and adapt to the continuously changing host environment experienced during decades of persistent infection. Mtb is continually exposed to endogenous reactive oxygen species (ROS) as part of normal aerobic respiration, as well as exogenous ROS and reactive nitrogen species (RNS) generated by the host immune system in response to infection. The magnitude of tuberculosis (TB) disease is further amplified by exposure to xenobiotics from the environment such as cigarette smoke and air pollution, causing disruption of the intracellular prooxidant–antioxidant balance. Both oxidative and reductive stresses induce redox cascades that alter Mtb signal transduction, DNA and RNA synthesis, protein synthesis and antimycobacterial drug resistance. As reviewed in this article, Mtb has evolved specific mechanisms to protect itself against endogenously produced oxidants, as well as defend against host and environmental oxidants and reductants found specifically within the microenvironments of the lung. Maintaining an appropriate redox balance is critical to the clinical outcome because several antimycobacterial prodrugs are only effective upon bioreductive activation. Proper homeostasis of oxido-reductive systems is essential for Mtb survival, persistence and subsequent reactivation. The progress and remaining deficiencies in understanding Mtb redox homeostasis are also discussed.
In this chapter, I argue for the global civil society as normatively and theoretically a new paradigm of global governance and also a possible emancipatory ‘cosmopolitan political project’ to the emerging challenges of democracy, justice and inclusive governance at the global level. Though global civil society is often perceived as a multilayered, contested and decentred space of associtionalism, I consider it an epic and irreversible ‘double movement’ of people seeking to transform hegemonic structures of global governance, protect human rights, minimize violence and increase the sphere of democratic life across the borderless world. And I suggest that this argument can be further explored, expanded and defended by offering at least four reasons.
First, I argue that globalization, benign or regressive, has created unique ‘political opportunity structures and processes’ rendering state-centric conventional theories of international relations and global governance completely irrelevant. Fuelled by the twin processes of associational and informational revolutions in the 1980s, global civil society has slowly and sturdily emerged as ‘a supranational sphere of social and political participation’ for a vast majority of people who have had not opportunity in the past to be heard in the hegemonic structures of international organizations. It is clear from the scope, reach and velocity of globalization that sovereignty of the modern nation-state has exhausted its imaginative power to continually secure the consent and allegiance of the population living under its shadow.
The origins of this book lie in the workshop of the Global Governance Research Network at the German Development Institute (DIE) in January 2007. The workshop expectedly brought together a brilliant, energetic and diverse group of senior scholars, policy makers and researchers from north and south setting forth a fruitful and productive process of introspection and reflection on emerging architectures of global governance. Encouraged by the instant consensus around some of the core ideas of the Global Governance Network, we immediately formulated a publishing project that understandably promised not only to examine ‘major power shifts’, but also broadened its net to include emerging powers and also ‘global civil society actors’ whom James Rosenau provocatively called ‘sovereignty free actors’ as major constituencies of the new global order (Rosenau 1990). As the world has become increasingly more globalized, more complex and also more vulnerable at this point of time, we undertake the task of comprehending and exploring political, economic, social and environmental processes of power shifts and prospects of deliberative democracy on a global scale. There is no doubt that global capitalism has come to witness one of the darkest and gloomiest periods in recent world history. Underlying this existential crisis is a deeper structural, political and moral crisis in the existing structures of global governance. Undoubtedly, the days of “casino capitalism” and “single superpower” are over as the world is keenly waiting for what Karl Polanyi would have called another ‘great transformation’.