Tunis, Tunisia

TIME Higher School

Tunis, Tunisia
Time filter
Source Type

Sanjeev Kumar P.M.,TIME Higher School | Chatteijee S.,TIME Higher School
2016 IEEE Annual India Conference, INDICON 2016 | Year: 2016

The brain is one of the vital organ of the body where it is the custodian of the involuntary and voluntary actions like walking, vision, memory. Now a days the most common brain disorders are Alzheimer's disease, Epilepsy (paralysis or stroke), tumors, brain tumors. Early diagnosis and proper treatment of brain tumors is required. The Computer Aided Diagnostic tools (CAD) can be used by the doctor for 2nd opinion to analyze the brain tumors and it is witnessing a rapid development in last decade. The CAD tools finds its major application in Medical (Macro and micro) imaging. The proposed diagnosis techniques is consists of three parts. Firstly a technique for segmenting the tumor, secondly optimize the data set and use Gray level Co-occurrence Matrix (GLCM) for texture analysis is proposed and lastly classify the tumor using Support vector machine classifier into Benign or malignant one is proposed. The classifier accuracy is obtained by using 3 kernels method that are Radial Basis Function, Linear and Polynomial kernel. In this paper the proposed algorithm and the GUI of CAD tools for Brain tumor detection and classification is designed and simulated in MATLAB. © 2016 IEEE.

Indu K.,TIME Higher School | Choondal J.J.,TIME Higher School
2016 IEEE Annual India Conference, INDICON 2016 | Year: 2016

In recent days, the most important problem that our society faces is low quality of drinking water. Water quality monitoring is important because contaminated drinking water can spread diseases faster than any other sources. With existing techniques, the general public is not aware of the potability of water. Lack of accurate and efficient low cost systems are a reason for poor awareness on the same. This paper focuses on modelling and developing a low cost water quality testing device and analysing its performance with the currently available products. The developed device can measure the parameters like pH, Total Dissolved Solids, Conductivity and Temperature. Its results are verified with samples of distilled water, salt water, tap water, dish wash and water, curd and performance is studied. © 2016 IEEE.

Debaille V.,TIME Higher School | Van Orman J.,University of Western States | Yin Q.-Z.,University of California at Davis | Amelin Y.,Australian National University
Earth and Planetary Science Letters | Year: 2017

The 176Lu–176Hf isotopic system is widely used for dating and tracing cosmochemical and geological processes, but still suffers from two uncertainties. First, Lu–Hf isochrons for some early Solar System materials have excess slope of unknown origin that should not be expected for meteorites with ages precisely determined with other isotopic chronometers. This observation translates to an apparent Lu decay constant higher than the one calculated by comparing ages obtained with various dating methods on terrestrial samples. Second, unlike the well constrained Sm/Nd value (to within 2%) for the chondritic uniform reservoir (CHUR), the Lu/Hf ratios in chondrites vary up to 18% when considering all chondrites, adding uncertainty to the Lu/Hf CHUR value. In order to better understand the Lu–Hf systematics of chondrites, we analyzed mineral fractions from the Richardton H5 chondrite to construct an internal Lu–Hf isochron, and set up a numerical model to investigate the effect of preferential diffusion of Lu compared to Hf from phosphate, the phase with the highest Lu–Hf ratio in chondrites, to other minerals. The isochron yields an age of 4647±210 million years (Myr) using the accepted 176Lu decay constant of 1.867±0.008×10−11yr−1. Combining this study with the phosphate fractions measured in a previous study yields a slope of 0.08855±0.00072, translating to a 176Lu decay constant of 1.862±0.016×10−11yr−1 using the Pb–Pb age previously obtained, in agreement with the accepted value. The large variation of the Lu/Hf phosphates combined with observations in the present study identify phosphates as the key in perturbing Lu–Hf dating and generating the isochron slope discrepancy. This is critical as apatite has substantially higher diffusion rates of rare earth elements than most silicate minerals that comprise stony meteorites. Results of numerical modeling depending of temperature peak, size of the grains and duration of the metamorphic event, show that diffusion processes in phosphate can produce an apparently older Lu–Hf isochron, while this effect will remain negligible in perturbing the Sm–Nd chronology. Our results suggest that only type 3 chondrites with the lowest metamorphic grade and large minerals with minimal diffusive effects are suitable for determination of the Lu–Hf CHUR values and the Lu decay constant respectively. © 2017 The Authors

Aissi S.,TIME Higher School | Aissi S.,University of Tunis | Sboui T.,Tunis el Manar University
Procedia Computer Science | Year: 2017

Volunteered geographic information (VGI) phenomenon offers an alternative mechanism for the acquisition of geospatial information. It has shown its effectiveness in various applications such as disaster management. However VGI suffers from a general lack of metadata quality assurance. This paper proposes an approach that aims to enhance VGI process by evaluating geospatial metadata quality. We introduce a set of indicators for geospatial metadata quality and we propose a method to evaluate them with respect to the context of VGI. © 2017 The Authors. Published by Elsevier B.V.

Debaille V.,TIME Higher School | O'Neill C.,Macquarie University | Brandon A.D.,University of Houston | Haenecour P.,TIME Higher School | And 4 more authors.
Earth and Planetary Science Letters | Year: 2013

A major change in Earth's geodynamics occurred ~3billionyears (Ga) ago, likely related to the onset of modern and continuous plate tectonics. However, the question of how Earth functioned prior to this time is poorly constrained. Here, we find a resolvable positive 142Nd anomaly in a 2.7Ga old tholeiitic lava flow from the Abitibi Greenstone Belt indicating that early-formed mantle heterogeneities persisted at least 1.8Ga after Earth's formation. This result contradicts the expected rapid early (~0.1Ga), as well as the slower present-day (~1Ga) mixing rates in the convecting mantle. Using a numerical modeling approach, we show that convective mixing is inefficient in absence of mobile-lid plate tectonics. The preservation of a 142Nd anomaly until 2.7Ga ago can be explained if throughout the Hadean and Archean, Earth was characterized by a stagnant-lid regime, possibly with sporadic and short subduction episodes. The major change in geodynamics observed around ~3Ga ago can then reflect the transition from stagnant-lid plate tectonics to modern mobile-lid plate tectonics. Solving the paradox of a convective but poorly-mixed mantle has implications not only for Archean Earth, but also for other planets in the solar system such as Mars. © 2013 Elsevier B.V.

Mhiri F.,University of Carthage | Sethom K.,University Pierre and Marie Curie | Bouallegue R.,TIME Higher School
Journal of Network and Computer Applications | Year: 2013

The femtocell concept is an emerging technology for deploying the next generation of the wireless networks, aiming at indoor coverage enhancement, increasing capacity, and offloading the overlay macrocell traffic. Nevertheless, one of the most critical issues in femtocells is the potential interference between nearby femtocells and from femtocells to macrocells or to mobile handsets, thus mitigating the overall system capacity. In this paper, we have discussed mechanisms which can be deployed to lessen the interference and increase the user capacity. Therefore, we provide a survey on the different interference and resource management techniques in Self-Organizing Network according to specifics classification criteria. These techniques derive from the following approaches: power control, proper cell planning, frequency reuse, OFDMA, self-configuration and self-optimization, conventional TDD, etc. These techniques can be applied separately and can be used as hybrid. A qualitative comparison among the different approaches and techniques is provided at the end of this paper. © 2012 Elsevier Ltd.

O'Neill C.,Macquarie University | Debaille V.,TIME Higher School
Earth and Planetary Science Letters | Year: 2014

Geodynamic modelling of Hadean/Eoarchaean tectonics typically requires higher rates of internal heat production, and higher mantle temperatures, in models that possess temperature-dependent viscosity and a yield criterion. In such models under Hadean conditions, for a wide range of geodynamic configurations and modelling approaches, subduction has a propensity to fail. This has led to the suggestion that the predominant tectonic regime in the Hadean was stagnant-lid convection, with intermittent recycling events. Various lines of evidence support this suggestion, from i) the long mixing time of mantle isotopic anomalies or compositional heterogeneities, such as 142Nd, 182W, and platinum group elements, to ii) the long residence time of the Hadean protolith to the Jack Hills zircons, and iii) thermal evolution models, which typically require lower heat flux in the past to avoid the "Archaean thermal catastrophe". The framework provided by stagnant lid, or episodic overturn, convection, iv) provides an explanation for the formation of early Archaean TTGs and greenstones, and v) explains the interleaving arc-plume sequence observed in many Archaean terranes, suggesting subduction initiation events may have been common, increasing their preservation potential. Implications include a low magnetic field strength in the Hadean, which is consistent with emerging paleointensity data from these times. © 2014 Elsevier B.V.

Galante J.,University of Cardiff | Galante I.,University of Buenos Aires | Bekkers M.-J.,TIME Higher School | Gallacher J.,University of Cardiff
Journal of Consulting and Clinical Psychology | Year: 2014

Objective: Kindness-based meditation (KBM) is a rubric covering meditation techniques developed to elicit kindness in a conscious way. Some techniques, for example, loving-kindness meditation and compassion meditation, have been included in programs aimed at improving health and well-being. Our aim was to systematically review and meta-analyze the evidence available from randomized controlled trials (RCTs) comparing the effects of KBM on health and well-being against passive and active control groups in patients and the general population. Method: Searches were completed in March 2013. Two reviewers applied predetermined eligibility criteria (RCTs, peer-reviewed publications, theses or conference proceedings, adult participants, KBM interventions) and extracted the data. Meta-analyses used random-effects models. Results: Twenty-two studies were included. KBM was moderately effective in decreasing self-reported depression (standard mean difference [Hedges's g] = -0.61, 95% confidence interval [CI] [-1.08, -0.14]) and increasing mindfulness (Hedges's g = 0.63, 95% CI [0.22, 1.05]), compassion (Hedges's g = 0.61, 95% CI [0.24, 0.99]) and self-compassion (Hedges's g = 0.45, 95% CI [0.15, 0.75]) against passive controls. Positive emotions were increased (Hedges's g = 0.42, 95% CI [0.10, 0.75]) against progressive relaxation. Exposure to KBM may initially be challenging for some people. Results were inconclusive for some outcomes, in particular against active controls. The methodological quality of the reports was low to moderate. Results suffered from imprecision due to wide CIs deriving from small studies. Conclusions: KBM showed evidence of benefits for the health of individuals and communities through its effects on well-being and social interaction. Further research including well-conducted large RCTs is warranted. © 2014 American Psychological Association.

Mezger K.,University of Bern | Debaille V.,TIME Higher School | Kleine T.,University of Munster
Space Science Reviews | Year: 2013

Geochemical investigation of Martian meteorites (SNC meteorites) yields important constraints on the chemical and geodynamical evolution of Mars. These samples may not be representative of the whole of Mars; however, they provide constraints on the early differentiation processes on Mars. The bulk composition of Martian samples implies the presence of a metallic core that formed concurrently as the planet accreted. The strong depletion of highly siderophile elements in the Martian mantle is only possible if Mars had a large scale magma ocean early in its history allowing efficient separation of a metallic melt from molten silicate. The solidification of the magma ocean created chemical heterogeneities whose ancient origin is manifested in the heterogeneous 142Nd and 182W abundances observed in different meteorite groups derived from Mars. The isotope anomalies measured in SNC meteorites imply major chemical fractionation within the Martian mantle during the life time of the short-lived isotopes 146Sm and 182Hf. The Hf-W data are consistent with very rapid accretion of Mars within a few million years or, alternatively, a more protracted accretion history involving several large impacts and incomplete metal-silicate equilibration during core formation. In contrast to Earth early-formed chemical heterogeneities are still preserved on Mars, albeit slightly modified by mixing processes. The preservation of such ancient chemical differences is only possible if Mars did not undergo efficient whole mantle convection or vigorous plate tectonic style processes after the first few tens of millions of years of its history. © 2012 Springer Science+Business Media Dordrecht.

Reed S.M.,TIME Higher School
The American journal of nursing | Year: 2014

In 2012, acute care hospitals in the United States reported 30,100 central line-associated bloodstream infections (CLABSIs) to the National Healthcare Safety Network of the Centers for Disease Control and Prevention. Known to substantially increase morbidity, length of stay, and cost of care, CLABSIs are associated with a mortality rate of 12% to 25% and an additional cost of $22,885 to $29,330 per incident. Following five months with a sustained CLABSI rate of zero per 1,000 catheter days, the acuity adaptable critical care unit at Geisinger Medical Center in Danville, Pennsylvania, saw the CLABSI rate spike to 3.97 per 1,000 catheter days in March 2011, prompting a quality improvement project and, ultimately, the implementation within the unit of a champion team program to guide central line care.

Loading TIME Higher School collaborators
Loading TIME Higher School collaborators