1,685 research outputs found
Interaction of mixed mode loading on cyclic debonding in adhesively bonded composite joints
A combined experimental and analytical investigation of an adhesively-bonded composite joint was conducted to characterize the fracture mode dependence of cyclic debonding. The system studied consisted of graphite/epoxy adherends bonded with EC 3445 adhesive. Several types of specimens are tested which provide the cyclic debond growth rate measurements under various load conditions: mode 1, mixed mode 1 to 2, and mostly mode 2. This study shows that the total strain-energy-release rate is the governing factor for cyclic debonding
Crowd Counting with Decomposed Uncertainty
Research in neural networks in the field of computer vision has achieved
remarkable accuracy for point estimation. However, the uncertainty in the
estimation is rarely addressed. Uncertainty quantification accompanied by point
estimation can lead to a more informed decision, and even improve the
prediction quality. In this work, we focus on uncertainty estimation in the
domain of crowd counting. With increasing occurrences of heavily crowded events
such as political rallies, protests, concerts, etc., automated crowd analysis
is becoming an increasingly crucial task. The stakes can be very high in many
of these real-world applications. We propose a scalable neural network
framework with quantification of decomposed uncertainty using a bootstrap
ensemble. We demonstrate that the proposed uncertainty quantification method
provides additional insight to the crowd counting problem and is simple to
implement. We also show that our proposed method exhibits the state of the art
performances in many benchmark crowd counting datasets.Comment: Accepted in AAAI 2020 (Main Technical Track
Relaxation of Collective Excitations in LJ-13 Cluster
We have performed classical molecular dynamics simulation of
cluster to study the behavior of collective excitations. In the solid ``phase''
of the cluster, the collective oscillation of the monopole mode can be well
fitted to a damped harmonic oscillator. The parameters of the equivalent damped
harmonic oscillator-- the damping coefficient, spring constant, time period of
oscillation and the mass of the oscillator -- all show a sharp change in
behavior at a kinetic temperature of about . This marks yet another
characteristic temperature of the system, a temperature below which
collective excitations are very stable, and at higher temperatures the single
particle excitations cause the damping of the collective oscillations. We argue
that so long as the cluster remains confined within the global potential energy
minimum the collective excitations do not decay; and once the cluster comes out
of this well, the local potential energy minima pockets act as single particle
excitation channels in destroying the collective motion. The effect is manifest
in almost all the physical observables of the cluster.Comment: Revised and enlarged. 6 pages RevTeX style. 7 eps figures available
on request. To appear in J Chem Phy
Heavy landing of Parapenaeopsis stylifera (M. Edw.) at Bombay during post-monsoon 1984
New Ferry Wharf is a major fish landing centre in Greater Bombay where fishing activity generally resumes in September after a period of lull during the southwest monsoon. This centre accounted for an annual (July-June) average of 7,530 tonnes of penaeid prawns of which Parapenaeopsis stylifera constituted 59.6%. The size (total length) of P. stylifera ranged from 58 to 103 mm for males and from 63 to 118 mm for females with the modal size at 83 mm and 103 mm for the respective sexes. The incidence of such huge catch all along the coast at about the same time was probably triggered by some oceanographic factors such as large scale upwelling of oxygen minimum layer which might have pushed the stock towards the shore
Unusually high landings of some penaeid prawns at Bombay
An unusual high landings of mainly two species of penaeid prawns, Metapenaeus monoceros and Metapenaeopsis stridulans, in the New Ferry wharf, an important trawl landing centre in Greater Bombay,have been reported in October and November ,1982 and the particulars are illustrated
On placement and dynamic power control of femtocells in LTE HetNets
Femto cells a.k.a. Low Power Nodes (LPNs) are used to improve indoor data rates as well as to reduce traffic load on macro Base Stations (BSs) in LTE cellular networks. These LPNs are deployed inside office buildings and residential apartment complexes to provide high data rates to indoor Users. With high SINR (Signal-to-Interference plus Noise Ratio) the users experience good throughput, but the SINR decreases significantly because of interference and obstacles such as building walls, present in the communication path. So, efficient placement of Femtos in buildings while considering Macro-Femto interference is very crucial for attaining desirable SINR. At the same time, minimizing the power leakage in order to improve the signal strength of outdoor users in a high interference (HIZone) around the building area is important. In our work, we have considered obstacles (walls, floors) and interference between Macro and Femto BSs. To be fair to both indoor and outdoor users, we designed an efficient placement and power control SON (Self organizing Network) algorithm which optimally places Femtos and dynamically adjusts the transmission power of Femtos based on the occupancy of Macro users in the HIZone. To do this, we solve two Mixed Integer Programming (MIP) methods namely: Minimize number of Femtos (MinNF) method which guarantees threshold SINR (SINRTh) -2dB for all indoor users and optimal Femto power (OptFP) allocation method which guarantees SINRTh (- 4 dB) for indoor users with the Macro users SINR degradation as lesser than 2dB
Obstructive sleep apnea: Awakening the hidden truth
Obstructive sleep apnea (OSA) is a common type of sleep apnea and is caused by obstruction of upper airway. Sleep apnea is clinically defined as frequent episodes of apnea, hypopnea and symptoms of functional impairment, which could be life.threatening and associated with extreme daytime hyper somnolence, dysfunction, discrements in health.related quality of life, automobile accidents, and cardiovascular morbidity and mortality. Etiopathogenic factors that contribute to OSA include reduced upper.airway dilator muscle activity during sleep, upper.airway anatomical features, ventilatory control insufficiency, lung volume, and rostral fluid shifts. The presence of risk factors such as age, gender and obesity increases the incidence of OSA. The repetitive nocturnal hypoxemia experienced by patients with OSA is associated with activation of a number of neural, humoral, thrombotic, metabolic, and inflammatory disease mechanisms, all of which have also been implicated in the pathophysiology of various systemic diseases. This article summarizes the etiopathogenesis, epidemiology, associated systemic diseases such as cardiovascular diseases, diabetes, and dental diseases with OSA and the influence of tongue on oropharyngeal airway in OSA patients. Key words: Apnea, breathlessness, snorin
Radio Link Simulator
The need for transmission of data over HF and VJUHF radio is increasing. There is a major disadvantage in testing the link in a field trial as propagation condition of the medium (especially HF) can be unpredictable and link condition may never again be the same. A simulator to create the atmospheric conditions, repeatably as required,to test the system behaviour is evident. The various propagation effects can be mathematically modelled, to get the signal affected by thechannel. Models for Gaussian, Rayleigh and Rice distributions and the implementation of the simulator using latest state-of-the-art DSP techniques are discussed
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