48 research outputs found
Optimal Multi-Modes Switching Problem in Infinite Horizon
This paper studies the problem of the deterministic version of the
Verification Theorem for the optimal m-states switching in infinite horizon
under Markovian framework with arbitrary switching cost functions. The problem
is formulated as an extended impulse control problem and solved by means of
probabilistic tools such as the Snell envelop of processes and reflected
backward stochastic differential equations. A viscosity solutions approach is
employed to carry out a finne analysis on the associated system of m
variational inequalities with inter-connected obstacles. We show that the
vector of value functions of the optimal problem is the unique viscosity
solution to the system. This problem is in relation with the valuation of firms
in a financial market
The philosophy of energy consumption in North Africa, contribution of artificial intelligence
Some people in North Africa have been accustomed to getting everything, from the consumption of various goods, to luxurious housing, to travel from one country to another, unaware that the necessities of this way of life are very energy intensive. These countries, too, are unaware of the importance and necessity of opening up to each other in order to work together to raise awareness of energy consumption. Through this research, which is based on a scientific approach combining technology, human and social sciences and statistical studies, we have tried to highlight the importance of logical energy consumption while explaining that the consequences will be unexpected in the future in the event of an energy shortage in North Africa
Viscosity solutions of systems of PDEs with interconnected obstacles and Multi modes switching problems
This paper deals with existence and uniqueness, in viscosity sense, of a
solution for a system of m variational partial differential inequalities with
inter-connected obstacles. A particular case of this system is the
deterministic version of the Verification Theorem of the Markovian optimal
m-states switching problem. The switching cost functions are arbitrary. This
problem is connected with the valuation of a power plant in the energy market.
The main tool is the notion of systems of reflected BSDEs with oblique
reflection.Comment: 36 page
33 Diagnostic accuracy of cardiovascular screening using pocket-size ultrasound in patients with dyspnea in the emergency setting
A Characterisation of Smart Grid DoS Attacks
Traditional power grids are evolving to keep pace with the demands of the modern age. Smart grids contain integrated IT systems for better management and efficiency, but in doing so, also inherit a plethora of cyber-security threats and vulnerabilities. Denial-of-Service (DoS) is one such threat. At the same time, the smart grid has particular characteristics (e.g. minimal delay tolerance), which can influence the nature of threats and so require special consideration. In this paper, we identify a set of possible smart grid-specific DoS scenarios based on current research, and analyse them in the context of the grid components they target. Based on this, we propose a novel target-based classification scheme and further characterise each scenario by qualitatively exploring it in the context of the underlying grid infrastructure. This culminates in a smart grid-centric analysis of the threat to reveal the nature of DoS in this environment
Prospective Observational Study on acute Appendicitis Worldwide (POSAW)
Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments.info:eu-repo/semantics/publishedVersio
Prospective Observational Study on acute Appendicitis Worldwide (POSAW)
Background: Acute appendicitis (AA) is the most common surgical disease, and appendectomy is the treatment of choice in the majority of cases. A correct diagnosis is key for decreasing the negative appendectomy rate. The management can become difficult in case of complicated appendicitis. The aim of this study is to describe the worldwide clinical and diagnostic work-up and management of AA in surgical departments.Methods: This prospective multicenter observational study was performed in 116 worldwide surgical departments from 44 countries over a 6-month period (April 1, 2016-September 30, 2016). All consecutive patients admitted to surgical departments with a clinical diagnosis of AA were included in the study.Results: A total of 4282 patients were enrolled in the POSAW study, 1928 (45%) women and 2354 (55%) men, with a median age of 29 years. Nine hundred and seven (21.2%) patients underwent an abdominal CT scan, 1856 (43.3%) patients an US, and 285 (6.7%) patients both CT scan and US. A total of 4097 (95.7%) patients underwent surgery; 1809 (42.2%) underwent open appendectomy and 2215 (51.7%) had laparoscopic appendectomy. One hundred eighty-five (4.3%) patients were managed conservatively. Major complications occurred in 199 patients (4.6%). The overall mortality rate was 0.28%.Conclusions: The results of the present study confirm the clinical value of imaging techniques and prognostic scores. Appendectomy remains the most effective treatment of acute appendicitis. Mortality rate is low.</p
The philosophy of energy consumption in North Africa, contribution of artificial intelligence
Some people in North Africa have been accustomed to getting everything, from the consumption of various goods, to luxurious housing, to travel from one country to another, unaware that the necessities of this way of life are very energy intensive. These countries, too, are unaware of the importance and necessity of opening up to each other in order to work together to raise awareness of energy consumption. Through this research, which is based on a scientific approach combining technology, human and social sciences and statistical studies, we have tried to highlight the importance of logical energy consumption while explaining that the consequences will be unexpected in the future in the event of an energy shortage in North Africa