110 research outputs found
Preventing blow up by convective terms in dissipative PDEs
We study the impact of the convective terms on the global solvability or
finite time blow up of solutions of dissipative PDEs. We consider the model
examples of 1D Burger's type equations, convective Cahn-Hilliard equation,
generalized Kuramoto-Sivashinsky equation and KdV type equations, we establish
the following common scenario: adding sufficiently strong (in comparison with
the destabilizing nonlinearity) convective terms to equation prevents the
solutions from blowing up in finite time and makes the considered system
globally well-posed and dissipative and for weak enough convective terms the
finite time blow up may occur similarly to the case when the equation does not
involve convective term.
This kind of result has been previously known for the case of Burger's type
equations and has been strongly based on maximum principle. In contrast to
this, our results are based on the weighted energy estimates which do not
require the maximum principle for the considered problem
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Probabilistic Value-Deviation-Bounded Source-Dependent Bit-Level Channel Adaptation for Approximate Communication
Computing systems that can tolerate effects of errors in their communicated
data values can trade this tolerance for improved resource efficiency. Many
important applications of computing, such as embedded sensor systems, can
tolerate errors that are bounded in their distribution of deviation from
correctness (distortion). We present a channel adaptation technique which
modulates properties of I/O channels typical in embedded sensor systems, to
provide a tradeoff between I/O power dissipation and distortion of communicated
data. We provide an efficient-to-compute formulation for the distribution of
integer distortion accounting for the distribution of transmitted values. Using
this formulation we implement our value-deviation-bounded (VDB) channel
adaptation. We experimentally quantify the achieved reduction in power
dissipation on a hardware prototype integrated with the required programmable
channel modulation circuitry. We augment these experimental measurements with
an analysis of the distributions of distortions. We show that our probabilistic
VDB channel adaptation can provide up to a 2 reduction in I/O power
dissipation. When synthesized for a miniature low-power FPGA intended for use
in sensor interfaces, a register transfer level implementation of the channel
adaptation control logic requires only 106 flip-flops and 224 4-input LUTs for
implementing per-bit channel adaptation on serialized streams of 8-bit sensor
data
The impact of supply chain coordination on the enviroment
Cataloged from PDF version of article.Emission regulating mechanisms have been proposed by the policy makers to
reduce the carbon emissions resulting from the industrial activities. We study
the channel coordination problem of a two-level supply chain (i.e., a buyer and
a vendor) under emission regulations. We first analyze a two-echelon chain that
operates to meet the deterministic demand of a single product in the infinite
horizon using a lot-for-lot policy under cap and trade, carbon tax and carbon
cap policies. We analytically show and numerically illustrate that the average
annual emissions of the system do not necessarily decrease when the buyer and
the vendor make coordinated decisions. This implies coordination may not be
good for the environment in terms of emissions related performance measures.
We further extend our analysis under the emission regulating mechanisms mentioned
above for a two-level supply chain in which the buyer operates to meet
the stochastic demand of a single product. In both deterministic and stochastic
demand settings, we propose coordination mechanisms including quantity discounts,
fixed payments, carbon-credit sharing and carbon-credit price discounts
that compensate the buyer’s loss when the system’s costs are minimized or profits
are maximized.Çetinkaya, BilgesuM.S
Synthesis of novel oxadiazole derivatives and their cytotoxic activity against various cancer cell lines
Caffeic acid (CA), ferulic acid (FA) and caffeic acid phenethyl ester (CAPE) have a broad anticancer effect on various cell lines. In this study, nine ferulic and caffeic acid-based 1,2,4 and 1,3,4 oxadiazole molecular hybrids were synthesized and their cytotoxic activity was evaluated mainly against Glioblastoma (GBM) cell lines. Compounds 1 and 5 exhibited the highest inhibitory activity against three different GBM cell lines (LN229, T98G, and U87), without toxicity to healthy human mesenchymal stem cells (hMSC). In addition, their cytotoxicity was also evaluated against three additional cancer cell lines and more inhibitory results were found than GBM cell lines. The IC50 values of compound 5 in U87, T98G, LN229, SKOV3, MCF7, and A549 cells were determined as 35.1, 34.4, 37.9, 14.2, 30.9, and 18.3 µM. In the light of biological activity studies, the developed compounds have a high potential to lead studies for the development of new drug candidates for the treatment of cancer
10 years of Master of Science in Geospatial Technologies: Development of a Web App with GeoTech students Data.
Kivrak, B., Oliveira, T. H. M. D., & Painho, M. (2018). 10 years of Master of Science in Geospatial Technologies: Development of a Web App with GeoTech students Data. Poster session presented at 10th GeoMundus Conference - GeoMundus 2018, Lisbon, Portugal.Master of Science in Geospatial Technologies is aimed at graduates wishing to obtain qualifications in fields where geographic information is applied and intend to have a multicultural experience. Geospatial information technologies have their roots primarily in three distinct areas: geosciences, computational technologies, and information science. Students of the Master in Geospatial Technologies degree will be able to develop applications in Geoinformation systems, use GIS tools for analysis of spatial relations or manage natural and human resources strategically. This poster presents a web application, built with the use of Esri’s Web App Builder, in which is possible to reach specific information about Partner Universities, How many students from each countries attend the program, the Location of Partner Universities, Program Links and information about Students, their origins and their Master Thesis. The Geotech Master Students Map Application provides an easy access to reach detailed information about the Master of Science in Geospatial Technologies Program.publishersversionpublishe
Evaluation of Physical Exercise'S Effects on Low Back Pain Among University Students With Short Form-36 and Oswestry Disability Index
DergiPark: 762681tmsjAims: This study aims to investigate the main effects of physical exercise on lower back pain with the Short Form-36 Health Survey and Oswestry Disability Index scores. Methods: University students between 18-25 years old who suffer from low back pain were enrolled in the study. Short Form-36 Health Survey and Oswestry Disability Index were used as the reference scales of lower back pain and quality of life, respectively. There are some questions in the questionnaire to scale the average comfort of the place they sleep and sit during the day, which is the result of the Personal Comfort Score. The Mann-Whitney U test was used for non-normal distributed variables. Correlation and Linear Regression were used to analyze data. SPSS 25.0 was used for all statistical analysis. Results: A total of 139 university students (94 females, 45 males) were included in the study. The median age was 20 years (IQR=2) for female students and 20 years (IQR=1) for male students. Oswestry Disability Index scores of fe- male students were higher, while Short Form-36 scores were lower than the male students. Male students' physical functioning scores were higher than female students. Each one-unit increase in Personal Comfort Score is associated with an increase in the rate between the energy/fatigue (3.34 units). Body Mass Index considerably affected the pain and Oswestry Disability Score, an increase in one unit of baseline BMI upsurged the Short Form-36 pain score to 0.13, and Oswestry disability score to 0.55. Conc- lusion: In our study, Body Mass Index is found to be associated with Oswestry Disability Index and Short Form-36 score, which are used for the severity of low back pain and defining the life quality and of patients. PCS had a positive correlation between energy/fatigue. In addition, There was a positive correlation between physical exercise and general health score
Evaluation of spinal-paraspinal parameters to determine segmentation of the vertebrae
Purpose: We aimed to evaluate whether lumbar vertebrae can be correctly numbered using auxiliary parameters. Material and methods: Vertebra corpus shape, O’Driscoll classification, lumbosacral axis angle, last two square vertebra dimensions, orifice of right renal artery (RRA), orifice of celiac truncus (CT), orifice of superior mesenteric artery (SMA), vena cava inferior confluence (CVC), abdominal aorta bifurcation (AB), and iliolumbar ligament were evaluated in this study. Results: Lumbosacral transitional vertebrae (LSTV) were observed in 13 (9%) patients. The most common locations of the paraspinal parameters were: RRA: L1 vertebrae (45%), SMA: L1 vertebrae (66%), CT: T12 vertebrae (46%), AB: L4 vertebrae (63%), and CVC: L4 vertebrae (52%). Conclusions: According to the results of our study, no single parameter in the magnetic resonance imaging can accurately indicate the number of vertebrae without counting the levels. As a result, we believe that these parameters may be suspicious in terms of the presence of LSTV rather than the correct level
Transient and steady state analysis of drill cuttings transport phenomena under turbulent conditions
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