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In this work, a new compact, low profile, frequency, and end-fire pattern reconfigurable antenna is presented. The proposed antenna consists of four parasitic elements and an electric-inductive-capacitive (ELC) resonator enclosed with a closed ring resonator (CRR). The reconfigurability in the proposed antenna is achieved with the help of five PIN diodes (D1–D5) embedded on the top surface of the substrate. The diode (D1) is implanted between ELC and CRR resonators for frequency reconfigurability. The other four diodes (D2–D5) are implanted between the ground plane and four parasitic elements to control the electrical length of the ground plane to achieve pattern diversity. The ground plane and parasitic elements steer the primary omni-directional beam to bi-directional and uni-directional end-fire radiation at multiple frequencies. The proposed antenna exhibits multiband operation and end-fire pattern diversity depending upon the different states of PIN diodes. The overall size of the proposed antenna is 0.20λ0× 0.17λ0× 0.009λ0, where λ0 is calculated at the lowest resonance frequency. The impedance bandwidth of the antenna ranges from 1.45 to 26.22%, while peak gain varies from 0.86 to 3.86 dBi depending upon the state of operation. The measured results are in agreement with the simulated results, which confirm the frequency and pattern diversity performance of the antenna. The proposed antenna can be used in back-to-back repeater systems.
Mungbean seeds, despite being protected inside the pod, are susceptible to pre-harvest sprouting (PHS) following rainfall due to lack of fresh seed dormancy (FSD), which deteriorates the quality of the seed/grain produced. Therefore, development of mungbean cultivars with short (10–15 days) period of FSD has become important to curtail losses incurred by PHS. In this study, we investigated variations in PHS, fresh seed germination (FSG) and activity of α-amylase enzyme in diverse mungbean genotypes. There was a wide variation in PHS tolerance and FSG among 163 genotypes examined and 14 genotypes were found to be tolerant (<20%) to PHS. Seed germination in a pod, a measure used to evaluate PHS, varied from 7.14% in germplasm accession Chamu 4 to 82.52% in cultivated variety IPM 2–3. There was a marked increase in α-amylase activity in genotypes showing high FSG and PHS, especially at 48 and 72 h after germination as compared with PHS tolerant genotypes. Therefore, α-amylase can be used as an effective biochemical marker to evaluate a large number of mungbean genotypes for FSD and PHS. Also, the variation in seed germinability as found in this study could be further used for mungbean improvement programme.
We prove a strong optimal Hardy–Sobolev inequality for the twisted Laplacian on ℂn. The twisted Laplacian is the magnetic Laplacian for a system of n particles in the plane, corresponding to the constant magnetic field. The inequality we obtain is strong optimal in the sense that the weight cannot be improved. We also show that our result extends to a one-parameter family of weighted Sobolev spaces.
Optimization is an important step in the design and development of a planar parallel manipulator. For optimization processes, workspace analysis is a crucial and preliminary objective. Generally, the workspace analysis for such manipulators is carried out using a non-dimensional approach. For planar parallel manipulators of two degrees of freedom (2-DOF), a non-dimensional workspace analysis is very advantageous. However, it becomes very difficult in the case of 3-DOF and higher DOF manipulators because of the complex shape of the workspace. In this study, the workspace shape is classified as a function of the geometric parameters, and the closed-form area expressions are derived for a constant orientation workspace of a three revolute–revolute–revolute (3-RRR) planar manipulator. The approach is also shown to be feasible for different orientations of a mobile platform. An optimization procedure for the design of planar 3-RRR manipulators is proposed for a prescribed workspace area. It is observed that the closed-form area expression for all the possible shapes of the workspace provides a larger solution space, which is further optimized considering singularity, mass of the manipulator, and a force transmission index.
Background: Essential tremor (ET) is the most common tremor disorder in adults. In addition to upper limbs, the tremor in ET may also involve head, jaw, voice, tongue, and trunk. Though head tremor (HT) is commonly present in patients with ET, large comparative studies of ET patients with HT (HT+) and without HT (HT−) are few. Methods: To determine whether ET with HT is a distinct clinical subtype by comparing ET patients with and without HT, a chart review of 234 consecutive patients with ET attending the neurology clinics of the National Institute of Mental Health and Neurosciences, India, was done. A movement disorder specialist confirmed the diagnosis of ET in all patients using the National Institutes of Health collaborative genetic criteria. Results: HT was present in 44.4% of the patients. Comparison between HT+ and HT− showed that the HT+ group patients: (1) were older, (2) had later onset of tremor, (3) had unimodal distribution of age at onset with a single peak in the fifth decade, (4) had more frequent voice tremor, and (5) were more likely to have mild cervical dystonia. HT was part of presenting symptoms in nearly two thirds of the ET patients and in the rest it was detected during clinical examination. Conclusions: Several demographic and clinical variables suggest that ET patients with HT have a distinct clinical phenotype.
We consider Tate cycles on an Abelian variety
defined over a sufficiently large number field
and having complexmultiplication. We show that there is an effective bound
so that to check whether a given cohomology class is a Tate class on
, it suffices to check the action of Frobenius elements at primes
. We also show that for a set of primes
of density 1, the space of Tate cycles on the special fibre
of the Néron model of
is isomorphic to the space of Tate cycles on
The workspace is often a critical parameter for optimum design of parallel manipulators. Workspace shape and area are two important considerations under this. In this paper, 5-R and 3-RRR planar parallel manipulators having symmetric link lengths are considered for workspace analysis. Here, symmetric means that the lengths of the first and second links of the legs are the same in all branches. Workspace analysis for such manipulators is normally done in a nondimensional way. The determination of the workspace area is one of the important parameters in the optimum design of a manipulator, and the determination of the area in terms of nondimensional parameters is extremely difficult in the case of 3-DOF and higher-DOF manipulators. In this paper, a geometric method is presented to determine different workspace shapes and areas. Based on this, all possible shapes of workspace are presented for both 5-R and 3-RRR planar parallel manipulators. For each case, a geometrical relationship between the link lengths is determined. The geometric approach gives a closed-form expression for the area calculation, which is not possible when adopting a nondimensional approach. In addition, this approach provides relationships between workspace shape and area and link lengths.
The Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) were compared with and without the addition of a brief processing speed test, the symbol digit modalities test (SDMT), for vascular cognitive impairment (VCI) screening at three to six months after stroke.
Patients with ischemic stroke and transient ischemic attack were assessed with MoCA and MMSE, as well as a formal neuropsychological battery three to six months after stroke. VCI was defined by impairment in any cognitive domain on neuropsychological testing. The area under the receiver operating characteristic curve (AUC) was used to compare test discriminatory ability.
One hundred and eighty-nine patients out of 327 (58%) had VCI, of whom 180 (95%) had vascular mild cognitive impairment (VaMCI), and nine (5%) had dementia. The overall AUCs of the MoCA and MMSE scores and performance at their respective cut-off points were equivalent in detecting VCI (AUCs: 0.87 (95% CI 0.83–0.91) vs. 0.84 (95% CI 0.80–0.88), p = 0.13; cut-offs: MoCA (≤23) vs. MMSE (≤26), sensitivity: 0.78 vs. 0.71; specificity: 0.80 vs. 0.82; positive predictive value: 0.84 vs. 0.84; negative predictive value: 0.72 vs. 0.67; and correctly classified 78.6% vs. 75.5%; p = 0.42). The AUCs of MMSE and MoCA were improved significantly by the SDMT (AUCs: MMSE+SDMT 0.90 (95% CI 0.87–0.93), p <0.001; MoCA+SDMT 0.91 (95% CI 0.88–0.94), p < 0.02).
The MoCA and MMSE are equivalent and moderately sensitive, and can be supplemented with the SDMT to improve their accuracy in VCI screening.
We present optical UBVRI photometric and low-resolution spectroscopic follow-up observations of a type II SN 2012aw in a nearby (~10 Mpc) galaxy M95 during 4 to 270 days post-explosion. The evolution characteristics of optical brightness and color are found to have striking similarity with the archetypal type IIP SN 1999em. The mid-plateau MV is −16.7 mag and the ejected nickel mass is ~0.06 M⊙. The presence and evolution of optical spectral features during 7d to 104d are also similar to SN 1999em as well as other normal type IIP events. The mid-plateau photospheric velocity is around 4200 km s−1 which is same as that of SN 2004et at similar phases, indicating similar energy of explosion i.e. 2 × 1051 erg s−1.
Supernova 2012A was discovered on 7.39UT, January, 2012 in the nearby galaxy NGC 3239 at an unfiltered magnitude of 14.6 and classified spectroscopically as a Type IIP event. Here, we present the optical photometric and spectroscopic follow-up of the event during 14d to 130d post explosion.
Ashok K. Dutt, Professor Emeritus in Geography, Planning and Urban Studies, University of Akron, USA,Vandana Wadhwa, Lecturer in the Department of Geography and Environment at Boston University, Massachusetts,Baleshwar Thakur, Former Head of the Department of Geography, Delhi School of Economics, University of Delhi,,Frank J. Costa, Professor Emeritus in Geography, Planning, Urban Studies and Public Administration at the University of Akron, USA.
Slums and squatter settlements are an essential facet of the urban landscape of most countries, more so that of the developing countries. They are also somewhat of a paradox in themselves. They are both: (i) a manifestation of urban poverty, and (ii) a reflection of the economic pull of urban areas. The definition of a slum varies from country to country, depending on the cultural mores and economic conditions. Slums are residential areas of least choice, characterized by dilapidated houses, poor ventilation, inadequate lighting, poor sanitation, lack of clean drinking water, overcrowding, convoluted street patterns, fire and flood hazards, poor facilities for education and health, unhygienic living conditions causing air and waterborne diseases. Socially, they are characterized by drug abuse, alcoholism, crime, vandalism, escapism, apathy and social isolation (Haggett et al., 1981; Census of India, 2001). In India, slums have been defined under Section 3 of the Slum Areas (Improvement and Clearance) Act, 1956, as areas where buildings are unfit for human habitation by reason of dilapidation, overcrowding, faulty arrangement and design of such buildings, narrowness or faulty arrangement of streets, lack of ventilation, light, sanitation facilities or any combination of these factors which are detrimental to safety, health and morals.
We describe the fabrication and structure of nanoscale thin films of β phase shape memory alloys with the nominal atomic stoichiometry Au7Cu5Al4 (corresponding to 5.8 wt% Al). These alloys possess properties that suggest they could be used in nanoscale actuators. The films described here are between 20 and 50 nm thick which is below the thickness at which some other shape memory alloys cease to transform. However, microstructural and X-ray studies confirm that the coatings still exhibit the displacive transformations that are a prerequisite for the shape memory effect.
The present paper presents the design and development of a dual-channel microwave rotary joint using coaxial waveguide as primary waveguide and rectangular waveguide as the secondary waveguide. Design is presented at 5.85–7.02 GHz with 20% bandwidth and at 14–14.5 GHz bands with 3.6% bandwidth using dual channel mode transducers exciting transverse electromagnetic (TEM) mode in the coaxial waveguide. Rectangular to coaxial waveguide transitions employing multi-stepped doorknob transitions are used to excite the TEM mode from the rectangular waveguide. The measured results for electrical parameters such as return loss, insertion loss of the dual-channel rotary joint are presented with 360° rotation of the rotary part with respect to the stator part.
A thin-amorphous MnOx layer using self-forming barrier process with a Cu-Mn alloy shows good adhesion and diffusion barrier properties between copper and dielectric layer, resulting in excellent reliability for stress and electromigration. Meanwhile, chemical vapor deposition (CVD) can be employed for conformal deposition of the barrier layer in narrow trenches and vias for future technology node. In our previous research, a thin and uniform amorphous MnOx layer could be formed on TEOS-oxide by thermal metal-organic CVD (MOCVD), showing a good diffusion barrier property. In addition, a good adhesion strength is necessary between a Cu line and a dielectric layer not only to ensure good SM and EM resistance but also to prevent film delamination under mechanical or thermal stress conditions during fabrication process such as chemical mechanical polishing or high temperature annealing. To date, no information is available with regard to the adhesion property of CVD-MnOx. In this work, we report diffusion barrier property in further detail and adhesion property in PVD-Cu/CVD-MnOx/SiO2/Si. The temperature dependence of the adhesion property is correlated with the chemical composition and valence state of Mn investigated with SIMS and Raman spectroscopy.
Substrates were p-type Si wafers having a plasma-TEOS oxide of 100nm in thickness. CVD was carried out in a deposition chamber. A manganese precursor was vaporized and introduced into the deposition chamber with H2 carrier gas. After the CVD, a Cu overlayer was deposited on some samples using a sputtering system in load lock chamber of the CVD machine. The diffusion barrier property of the MnOx film was investigated in annealed samples at 400 oC for 100 hours in a vacuum of better than 1.0×10-5 Pa. The Adhesion property of Mn oxide was investigated by Scotch tape test in the as-deposited and in the annealed Cu/CVD-MnOx/TEOS samples. The obtained samples were analyzed for thickness and microstructure with TEM, chemical bonding states of the MnOx layer with XPS, and composition of each layer with SIMS.
In the CVD deposition below 300 °C, no Cu delamination was observed both in the as-deposited and in the annealed Cu/CVD-MnOx/SiO2 samples. On the other hand, in the CVD deposition at 400 °C, the Cu films were delaminated from the CVD-MnOx/TEOS substrates. The XPS peak position of Mn 2p and Mn 3s spectra indicated that the valence state of Mn in the as-deposited barrier layer below 400 °C was 2+. Composition analysis with SIMS as well as Raman also indicated the presence of a larger amount of carbon at 400 °C than at less than 300 °C. The good adhesion between Cu and MnO could be attributed to an amount of carbon inclusion in the CVD barrier layer.
An ultrathin barrier layer of MnOx was grown using metal organic chemical vapor deposition (MOCVD) at an interface between Cu and SiO2 dielectric. The electronic transport properties of Cu/MnOx/SiO2/p-Si metal oxide semiconductor (MOS) devices showed leakage current density within the range of 10-8-10-7A/cm2 up to an electric field of 4MV/cm. The current density remained within the same range after bias temperature aging test at 3MV/cm for 6×103s at 550K. The capacitance-voltage curves of the MOS device having the MnOx layer grown at 473K do not show significant shift of flat band voltage after thermal annealing at 673K for 3.6×103s as well as after bias temperature aging test at 1MV/cm, 550K for 2.4×103 s. These results indicate that the ultrathin layer of MnOx is stable under the above conditions and prevents sufficiently Cu ion diffusion into the SiO2 dielectric.