Acoustic signature of an unmanned air vehicle exploitation for aircraft localisation and parameter estimation

"Higher harmonics in the acoustic spectrogram of an unmanned air vehicle in-flight; as obtained from a ground-based microphone measurement, is shown to be useful for estimating the vehicle's altitude, speed and true engine revolutions per minute. Specifically, the Doppler-shifted frequency time histories derived from spectrogram contours are used in this estimation approach which is based on a least mean square error fit to an Instantaneous frequency model proposed In the literature. Benefits of employing higher harmonics -rather than the fundamental only -in the computations are brought out. The results obtained are satisfactory. A possible system configuration for automatic detection and localisation of similar aircraft is briefly discussed here

DEMOCRACY AND DEMOGRAPHY

American democracy is under siege. This is so because of the confluence of three trends: (1) demographic change and residential segregation, which increasingly have placed more racially diverse Democratic Party voters in cities and suburbs, while rural areas have become more white and Republican; (2) a constitutional structure—particularly the Electoral College, the composition of the Senate, and the use of small, winner-take-all legislative districts—that gives disproportionate representation to rural populations; and (3) the willingness of this rural Republican minority to use its disproportionate power to further entrench counter-majoritarian structures, whether through extreme partisan gerrymandering, increased voter suppression efforts, court-packing, or outright rebellion against the results of democratic elections. These three trends create the very real prospect that for the foreseeable future a mostly white rural Republican minority wields disproportionate, structurally locked-in, power over a more diverse urban and suburban Democratic majority. A democracy cannot survive long under those conditions. In order to rescue the possibility of democratic self-government, we argue that judges must begin to apply heightened scrutiny to legislation or executive action that seeks to entrench the political power of a rural electoral minority or that discriminates against urban and suburban populations. In making this argument, we seek to revive the political process rationale for heightened judicial scrutiny that has long been associated with constitutional scholar John Hart Ely and his interpretation of Chief Justice Stone’s famous footnote 4 of the decision in United States v. Carolene Products Company. Both Stone and Ely were particularly focused on the potential ways the political system was skewed to deny Black people effective political representation, as well as the many circumstances through which de jure racial discrimination denied racial minorities equal rights. But there is no reason that the Carolene Products theory as elaborated by Ely needs to be confined only to this context. To the contrary, the whole point of Ely’s theory of judicial review is that it contemplates judicial intervention whenever the prevailing political system is systematically disadvantaging one group in order to lock in political advantages to another group. In such circumstances the democratic process is not functioning properly, and judicial intervention is not a threat to democracy, but a necessity in order to preserve democracy. We argue that our current political moment calls for a robust application of the Carolene/Ely principles of judicial review, and we provide examples of situations where heightened judicial review is appropriate. The democracy-protecting approach advocated in this Article also provides an additional basis for criticizing the newly minted, ahistorical “independent state legislature” theory embraced by some Supreme Court justices because it would allow minority factions to further disenfranchise the majority of the population by severely reducing, if not eliminating, the possibility for meaningful judicial review by state or federal courts

A Hybrid Peripheral Giant Cell Granuloma-Peripheral Ossifying Fibroma Lesion Presenting as a Solitary Gingival Enlargement

Clinical and radiographic presentations of gingival enlargements often overlap. Definitive diagnosis is made after histological evaluation of excised tissues. Sometimes this is also confusing because it may show features of different clinical entities producing a diagnostic dilemma. Hybrid lesions are lesions which present features from different pathologies. We present a case of hybrid lesion which shows features of peripheral giant cell granuloma (PGCG) and Peripheral ossifying fibroma (POsF) presenting as solitary gingival enlargement involving the maxilla in a 57 year old female patient. The clinical, radiographic and histological features are described in detail. The purpose of this paper is to highlight the importance of thorough evaluation of hybrid lesion to get a proper diagnosis, understand their biologic behaviour and plan treatment to minimise tissue destruction and prevent recurrence. This case also points to the need to reconsider our diagnostic criteria of various enlargements and incorporate hybrid lesions as distinct clinical entit

Physiology and plant pathology

The impact of physical sciences, particularly biochemistry, has played a significant role in understanding etiology and syndrome in pathogenesis. Critical tissue respiration and enzyme changes, deranged carbohydrate and nitrogen metabolism, transpiratory disturbances and ionic imbalance produced by fungal toxins, exaggerated auxin relationships, formation of abnormal metabolite (s) (phytoalexins) have all contributed to a better understanding of the 'sick' plant. Plant virologists have made phenomenal progress in the applied field of the biochemistry of the infected plant and some of the recent researches on the nature of viruses and control measures adopted are worth emulating in other fields of plant pathology. A new field is developing round environment and disease proneness. This has reference to the rice blast disease where low nyctotemperatures for a long enough period makes for alterations in the nitrogen metabolism of the host and is governed by the balance between primary nitrogen metabolism and secondary metabolic events leading to synthesis of structural metabolites

The experimental control of plant growth

This article does not have an abstract

Uptake of ions and metallic chelation in plants

This article does not have an abstract

Virus research

This article does not have an abstract

Spectrochemical studies on the uptake of ions by plants I. The Lundegardh flame technique of ash analysis of toxin/antibiotic invaded cotton plants

Spectrochemical analysis, using the standard Lundegardh flame emission (spark-in-flame) method, of cotton plants infected by Fusarium vasinfectum Atk., showed an increased uptake of Mg, Ca, Fe and Mn with decreased accumulation of K over the healthy plants. It is suggested that the derangement in the selective absorption of ions, seen in the infected plants, is more likely to have been caused by chemical agents (toxins) than physical causes such as plugging of vessels

Numerical Simulation of Diffuser of a Gas Turbine using the Actuator Disc Model

An analysis of the exhaust diffuser section of a gas turbine is presented by incorporating the reduced order mathematical model “actuator disc concept” that represents the last stage of the turbine. The actuator disc model is one of the simplified numerical methods for analyzing the aerodynamic performance of axial turbine stage. In which, the rotor and the stator of the turbine stages are modeled as zero thickness discs with a specified blade speed and zero speed respectively. Finite volume based commercial CFD package ANSYS FLUENT was employed for the numerical investigation of the applicability of the proposed simplified model. The compressible Navier-Stoke equations along with k- turbulent model were solved in the computational domain by incorporating suitable boundary conditions. The implementation of actuator disc boundary conditions is described in detail. The numerical results obtained from the proposed model are in good agreement with the experimental data available in the literature. The effect of casing angle on the performance of diffuser is presented