94 research outputs found
CFD simulation of flow past MAV wings
Turbulent flow past low aspect ratio (AR) thin wing used for two different MAV (Micro Air Vehicles) configurations
viz. Black Kite and Golden Hawk has been carried out in order to analyze their aerodynamic characteristics. The Reynolds (Re) number for these two wings based on the root chord are 2.4´105 and 1.72´ 105 respectively. These simulations have been carried out using the in-house flow solution code to solve the Unsteady Reynolds Averaged Navier Stokes (URANS) equations coupled to different turbulence models. The standard k-e model has been used to simulate the turbulence for the Black Kite wing. The
influence of three different turbulence models (standard k-e, SA and SST) in predicting the aerodynamic coefficient has been studied for the Golden Hawk configuration. In the present study the aerodynamic characteristics computed for the two wing configurations are compared with the CSIR-NAL experiments. The cross flow patterns and the tip vortex for the Golden Hawk wing are presented and discussed
CFD simulation using FLUENT and RANS3D - A validation exercise
The present work involves two-dimensional numerical simulation of three benchmark problems like (i) Laminar flow in a lid driven cavity (ii) Turbulent flow past a backward facing step and (iii) turbulent flow past NACA0012 aerofoil, using in-house flow solution code RANS3D and the commercially available FLUENT code. The results obtained using these codes are compared with the available measurement data and/or other computations
Formal Verification of Safety Properties for Ownership Authentication Transfer Protocol
In ubiquitous computing devices, users tend to store some valuable
information in their device. Even though the device can be borrowed by the
other user temporarily, it is not safe for any user to borrow or lend the
device as it may cause private data of the user to be public. To safeguard the
user data and also to preserve user privacy we propose and model the technique
of ownership authentication transfer. The user who is willing to sell the
device has to transfer the ownership of the device under sale. Once the device
is sold and the ownership has been transferred, the old owner will not be able
to use that device at any cost. Either of the users will not be able to use the
device if the process of ownership has not been carried out properly. This also
takes care of the scenario when the device has been stolen or lost, avoiding
the impersonation attack. The aim of this paper is to model basic process of
proposed ownership authentication transfer protocol and check its safety
properties by representing it using CSP and model checking approach. For model
checking we have used a symbolic model checker tool called NuSMV. The safety
properties of ownership transfer protocol has been modeled in terms of CTL
specification and it is observed that the system satisfies all the protocol
constraint and is safe to be deployed.Comment: 16 pages, 7 figures,Submitted to ADCOM 201
A prospective study on awareness of postnatal mothers regarding self and newborn care in a tertiary care centre in Mangalore, Karnataka
Background: Postnatal care is the important portion of maternal health care as it helps to assess the health status of mother and newborn. It promotes to rectify the defect and to identify the progress of the baby that is essential to solve the health issues.Methods: All 100 postnatal women were assessed regarding awareness of self and newborn care using structured questionnaire.Results: In this study maximum number were in age group of 21-25 years (42%). Majority of respondents were literate (88%). Main source of information regarding postnatal and neonatal care is given by health care personnel (49%). 77% cleaned the perineum after defecation and urination. 39% of postnatal mothers practice postnatal exercise. 54% were aware of spacing between two pregnancies. Majority of mothers agreed that colostrum is first breast milk and are aware on giving it to newborn (68%). 78% are aware of exclusively breast feeding baby for 6 months. 79% of postnatal women were aware vaccines prevent diseases in baby. Postnatal mothers had good awareness about self and newborn care.Conclusions: The first 48 hours after delivery is the time when the mother and baby are most vulnerable to morbidity and mortality associated with childbirth. Postnatal care is one of the most important maternal health care for not only prevention of impairment and disabilities, but also for reduction of maternal and neonatal mortality and morbidity
CHOKING IN A PSYCHIATRIC PATIENT - A CASE REPORT
Choking is one of the important types of asphyxia deaths. The incidences of which are not uncommon. The choking in children could be due toys, coins, marbles, nuts and any other small hard object or even sometimes due to stuffed in plastic bags whereas in adults most of the times food bolus or hard parts of food like bone pieces are responsible. It is mostly accidental in nature. It can cause coughing or sometimes airway obstruction leading to death. We present a case wherein a mentally ill person accidentally choked to death after consumption of food.
KEYWORDS: Choking; Asphyxial deaths; Food bolus; Airway obstruction
CHOKING IN A PSYCHIATRIC PATIENT - A CASE REPORT
Choking is one of the important types of asphyxia deaths. The incidences of which are not uncommon. The choking in children could be due toys, coins, marbles, nuts and any other small hard object or even sometimes due to stuffed in plastic bags whereas in adults most of the times food bolus or hard parts of food like bone pieces are responsible. It is mostly accidental in nature. It can cause coughing or sometimes airway obstruction leading to death. We present a case wherein a mentally ill person accidentally choked to death after consumption of food.
KEYWORDS: Choking; Asphyxial deaths; Food bolus; Airway obstruction
Organic Farming on Productivity of Rice and Soil Fertility under Alfisols of Southern Transition Zone of Karnataka, India
The research results concluded that the green manuring with organic manures increased the green manures biomass yield. Green manuring with FYM at sowing and incorporating insitu green manures enhanced the productivity of organically grown rice and soil fertility. The build up of soil available nutrients and microbial diversity were observed in organic farming
Don't Thrash: How to Cache Your Hash on Flash
This paper presents new alternatives to the well-known Bloom filter data
structure. The Bloom filter, a compact data structure supporting set insertion
and membership queries, has found wide application in databases, storage
systems, and networks. Because the Bloom filter performs frequent random reads
and writes, it is used almost exclusively in RAM, limiting the size of the sets
it can represent. This paper first describes the quotient filter, which
supports the basic operations of the Bloom filter, achieving roughly comparable
performance in terms of space and time, but with better data locality.
Operations on the quotient filter require only a small number of contiguous
accesses. The quotient filter has other advantages over the Bloom filter: it
supports deletions, it can be dynamically resized, and two quotient filters can
be efficiently merged. The paper then gives two data structures, the buffered
quotient filter and the cascade filter, which exploit the quotient filter
advantages and thus serve as SSD-optimized alternatives to the Bloom filter.
The cascade filter has better asymptotic I/O performance than the buffered
quotient filter, but the buffered quotient filter outperforms the cascade
filter on small to medium data sets. Both data structures significantly
outperform recently-proposed SSD-optimized Bloom filter variants, such as the
elevator Bloom filter, buffered Bloom filter, and forest-structured Bloom
filter. In experiments, the cascade filter and buffered quotient filter
performed insertions 8.6-11 times faster than the fastest Bloom filter variant
and performed lookups 0.94-2.56 times faster.Comment: VLDB201
Air-Abrasion in Dentistry: A Short Review of the Materials and Performance Parameters
The selection of abrasive material and parameters of the Air-Abrasion device for a particular application is a crucial detail. However, there are no standard recommendations or manuals for choosing these details; the operator must depend on his experience and knowledge of the procedure to select the best possible material and set of parameters. This short review attempts to identify some of the effects that the selection of material and parameters could have on the performance of the Air-Abrasion procedure for a particular application. The material and parameter data are collected from various studies and categorized according to the most popular materials in use right now. These studies are then analyzed to arrive at some inferences on the performance of Air-Abrasion materials and parameters. This review arrives at a few conclusions on the effectiveness of a material and parameter set, and that there is potential for developments in the area of standardizing parameter selection; also, there is scope for further studies on Bio-Active Glass as an alternative to the materials currently used in Air-Abrasion
Magnitude, temporal trends, and projections of the global prevalence of blindness and distance and near vision impairment: a systematic review and meta-analysis
Background: Global and regional prevalence estimates for blindness and vision impairment are important for the development of public health policies. We aimed to provide global estimates, trends, and projections of global blindness and vision impairment.
Methods: We did a systematic review and meta-analysis of population-based datasets relevant to global vision impairment and blindness that were published between 1980 and 2015. We fitted hierarchical models to estimate the prevalence (by age, country, and sex), in 2015, of mild visual impairment (presenting visual acuity worse than 6/12 to 6/18 inclusive), moderate to severe visual impairment (presenting visual acuity worse than 6/18 to 3/60 inclusive), blindness (presenting visual acuity worse than 3/60), and functional presbyopia (defined as presenting near vision worse than N6 or N8 at 40 cm when best-corrected distance visual acuity was better than 6/12).
Findings: Globally, of the 7·33 billion people alive in 2015, an estimated 36·0 million (80% uncertainty interval [UI] 12·9–65·4) were blind (crude prevalence 0·48%; 80% UI 0·17–0·87; 56% female), 216·6 million (80% UI 98·5–359·1) people had moderate to severe visual impairment (2·95%, 80% UI 1·34–4·89; 55% female), and 188·5 million (80% UI 64·5–350·2) had mild visual impairment (2·57%, 80% UI 0·88–4·77; 54% female). Functional presbyopia affected an estimated 1094·7 million (80% UI 581·1–1686·5) people aged 35 years and older, with 666·7 million (80% UI 364·9–997·6) being aged 50 years or older. The estimated number of blind people increased by 17·6%, from 30·6 million (80% UI 9·9–57·3) in 1990 to 36·0 million (80% UI 12·9–65·4) in 2015. This change was attributable to three factors, namely an increase because of population growth (38·4%), population ageing after accounting for population growth (34·6%), and reduction in age-specific prevalence (–36·7%). The number of people with moderate and severe visual impairment also increased, from 159·9 million (80% UI 68·3–270·0) in 1990 to 216·6 million (80% UI 98·5–359·1) in 2015.
Interpretation: There is an ongoing reduction in the age-standardised prevalence of blindness and visual impairment, yet the growth and ageing of the world’s population is causing a substantial increase in number of people affected. These observations, plus a very large contribution from uncorrected presbyopia, highlight the need to scale up vision impairment alleviation efforts at all levels
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