Mohamad Nassar - Academia.edu (original) (raw)

Papers by Mohamad Nassar

Lecture notes in networks and systems, Oct 13, 2022

Artificial Intelligence and Machine Learning

The scientific community is looking for efficient solutions to improve the quality of life in lar... more The scientific community is looking for efficient solutions to improve the quality of life in large cities because of traffic congestion, driving experience, air pollution, and energy consumption. This surge exceeds the capacity of existing transit infrastructure and parking facilities. Intelligent Parking Systems (SPS) that can accommodate short-term parking demand are a must-have for smart city development. SPS are designed to count the number of parked automobiles and identify available parking spaces. In this paper, we present a novel SPS based on real-time computer vision techniques. The proposed system provides features including: vacant parking space recognition, inappropriate parking detection, forecast of available parking spaces, and directed indicators toward various sorts of parking spaces (vacant, occupied, reserved and handicapped). Our system leverages existing video surveillance systems to capture, process image sequences, train computer models to understand and inte...

African Journal of Biological Sciences

Formal Aspects of Component Software, 2017

We introduce a novel framework for runtime enforcement of safe executions in component-based syst... more We introduce a novel framework for runtime enforcement of safe executions in component-based systems with multi-party interactions modeled using BIP. Our technique frames runtime enforcement as a sequential decision making problem and presents two alternatives for learning optimal strategies that ensure fairness between correct traces. We target both finite and infinite state-spaces. In the finite case, we guarantee that the system avoids bad-states by casting the learning process as a one of determining a fixed point solution that converges to the optimal strategy. Though successful, this technique fails to generalize to the infinite case due to need for building a dictionary, which quantifies the performance of each state-interaction pair. As such, we further contribute by generalizing our framework to support the infinite setting. Here, we adapt ideas from function approximators and machine learning to encode each state-interaction pairs' performance. In essence, we autonomously learn to abstract similar performing states in a relevant continuous space through the usage of deep learning. We assess our method empirically by presenting a fully implemented tool, so called RERL. Particularly, we use RERL to: 1) enforce deadlock freedom on a dining philosophers benchmark, and 2) allow for pair-wise synchronized robots to autonomously achieve consensus within a cooperative multi-agent setting.

Canadian Journal of Civil Engineering, 2021

The aim of this work is to estimate the seismic reliability of a simple typical two span lifeline... more The aim of this work is to estimate the seismic reliability of a simple typical two span lifeline base-isolated bridge designed to behave essentially elastic or as per the Canadian Highway Bridge Design Code, for seven localities in Quebec. Two limit states are considered for possible failure due to unacceptable damage: by flexure at pier-base and by displacement within the SIS. Main problem random variables (RVs) considered and modeled are: Seismic hazard, temperature, pier base dimensions and material mechanical properties. The Monte-Carlo method is used to evaluate each limit state reliability and probability of failure. Preliminary results reveal that notwithstanding the large temperature and seismic hazard variabilities between the seven sites in Quebec, the global reliability indices are almost uniform, around 3.45±0.02. Furthermore, security factor (i.e.1.25) on SIS displacement capacity results in reliability indices for SIS displacement are not levelled with the flexural re...

Bridges are structures of great socio-economic importance, but particularly vulnerable to earthqu... more Bridges are structures of great socio-economic importance, but particularly vulnerable to earthquakes. During the last few decades, seismic base isolation gained an increasing interest and is established as one of the most effective ways to protect bridges against earthquakes. Hysteretic properties of the isolation systems, notably the characteristic resistance,Qd, and the post-elastic stiffness, Kd, are of prime importance as they govern the seismic performance of based-isolated bridges. However, these properties vary under the effect of different conditions, including the temperature. In the absence of a reliability-based approach to take into account the variability of these properties, standards specify a bounding analysis method in which the bounding possible maximum and minimum values of Qd and Kd are used to evaluate the performance of baseisolated bridges under earthquakes. This approach is incoherent with the reliability-based design approaches, such as the LRFD, used by th...

Bahrain Medical Bulletin, 2016

Objectives: Adult intussusception is a rare entity. We present four cases of this condition. Desi... more Objectives: Adult intussusception is a rare entity. We present four cases of this condition. Design: Retrospective review. Setting: Surgical Department, Salmaniya Medical Centre. Method: During a period of 11 years (1992-2003), the presenting features, investigation, and management of four intussusception cases were reviewed. Results: Four cases were found in our records over this long period indicating its rarity. The patients were two females and two males with age ranging from 22 to 61 years. The presentation was right lower quadrant pain in two patients and bowel obstruction in the other two. Radiological investigation was done for all, but the diagnosis was confirmed on exploratory laparatomy. Most of them were of ileo-ileal origin. No malignancy was reported. Conclusion: Adult intussusception is a rare entity. Clinical awareness and radiological investigation are very important in diagnosis. Surgical treatment is the rule in all cases.

Engineering Structures, 2019

Seismic base isolation is widely used to ensure desirable performance of bridge structures agains... more Seismic base isolation is widely used to ensure desirable performance of bridge structures against earthquakes. Seismic response of base-isolated bridges is strongly dependent on seismic isolator's properties. However, these properties vary under the effect of multiple conditions such as temperature. The bounding analysis approach, recommended by current design codes to consider such variations, does not rigorously take into account the probability of a simultaneous occurrence of earthquakes with these conditions. As a result, base-isolated bridge design may not be optimised and the reliability of base-isolated bridges remains uncontrolled. This paper presents a probability-based reliability assessment method to consider the variations of seismic isolation properties under different conditions. Temperature, seismic hazard, the dimensions and the material mechanical properties of key structure elements are modelled as random variables. An application of the methodology is demonstrated through a case study of a base-isolated two span reinforced concrete bridge. Two limit states are considered: (1) in terms of the bending moment capacity of the bridge's pile and (2) in terms of the displacement capacity of the seismic isolator. Preliminary results reveal that, for the case-study bridge, the global reliability of the bridge is equal to the reliability of the limit state (2). This is because the reserve provided by the bias and security factors is applied in the case of the limit state (1) but not considered for the limit state (2). What's more, results reveal that for the case-study bridge, the seismic reliability depends on the seismic input severity more than on low temperature severity. This paper advances the basics of a method to assess the reliability of base-isolated bridges. Its application is demonstrated and preliminary results are obtained through a case study. A more systematic study using the proposed methodology should allow for the establishment of seismic guidelines with uniform target reliability. the seismic response of base-isolated bridges and was adopted by the AASHTO [15] and Eurocode 8 [16].

Future Computing and Informatics Journal, 2016

Actual problems that threaten organizations are the excessive unnecessary organizational processe... more Actual problems that threaten organizations are the excessive unnecessary organizational processes. The Business Process Reengineering (BPR) methodology is developed to improve the return of investment rates within organization. BPR guides to rearranging processes and removing unnecessary ones and consolidating the remaining processes into linear open system. Unfortunately, usage of modern Information Technology doesn't solve such problems in the Middle East countries and especially Egypt and doesn't realize the expected results. The limitations and drawbacks of IT projects refer mainly to the dependency on plan-driven team software process methodology that could not achieve frequently requirement changes of customers and usually exceeds estimated budget of the project. This research adopted the eXtreme Programming methodology using virtual team software process work providers in order to avoid these drawbacks and applied the proposed hybrid methodology to three main departments within Suez Canal Authority in Egypt

The British Accounting Review, 1996

This article reports a study of the way in which users of external financial reports view those r... more This article reports a study of the way in which users of external financial reports view those reports in a less developed country with a moderately sophisticated capital market. Most users consider that they make at least moderate use of corporate annual reports. What different user groups say about the extent to which they use reports is examined together with what they say about the number of reports read and the time spent reading them; there is some apparent inconsistency. The pattern of usage of the individual report sections is broadly consistent with that in developed countries except that greater attention is given to auditors' reports. Users complained of lack of comparability and consistency between different companies within a single industry and about lack of reliability. By comparison with developed countries, users relied more heavily on information obtained from the company, either from the annual report or via other channels. All these findings may reflect the financial reporting environment to be found in a less developed country. Users do not perceive themselves to suffer from significant difficulty in understanding financial information.