416 research outputs found
Performance Enhancement of Routing Protocols in Mobile Wireless Ad-Hoc Networks Using Fuzzy Reasoning Algorithm
The challenge in creating a routing protocol for ad-hoc networks is to design a single protocol that can adapt to the wide variety of conditions that can be present in any ad-hoc network enviroment. The routing protocol must perform efficiently in enviroments in which it suffers from high nodes mobility and many wireless transmission constraints. Because it it often impossible to know what enviroment the protocol will find itself in, and because the enviroment can change unpredictably, the routing protocol must be able to adapt automatically. In this thesis, we use a fuzzy reasoning algorithm (FRA) as a highly adaptive algorithm to achieve that goal. We will present the various application of that algorithm to ad-hoc routing protocols. Then, we will focus on four major applications that are the core of any ad-hoc routing protocol. These applications are: route lifetime estimation, local connectivity management, nodes affinity management, and active queue management. In the first method, the fuzzy reasoning is used to estimate the time route can stay active in the routing table. In the second method, fuzzy reasoning is used to optimize the maximum time period that can transpire before the node broadcast the ‘Hello” messages. Mapping the relationship between the signal strength fluctuation and links lifetime is presented in the third method. Finally, in the last method fuzzy reasoning is used for network congestion estimation and estimating time to start dropping incoming packets. Extensive performance analysis via simulation proves the effectiveness of using the FRA to improve the accuracy of routing protocol parameters and hence the overall network performance
Modeling and Control for Smart Grid Integration of Solar/Wind Energy Conversion System
Performance optimization, system reliability and operational efficiency are key characteristics of smart grid systems. In this paper a novel model of smart grid-connected PV/WT hybrid system is developed. It comprises photovoltaic array, wind turbine, asynchronous (induction) generator, controller and converters. The model is implemented using MATLAB/SIMULINK software package. Perturb and observe (P&O) algorithm is used for maximizing the generated power based on maximum power point tracker (MPPT) implementation. The dynamic behavior of the proposed model is examined under different operating conditions. Solar irradiance, temperature and wind speed data is gathered from a grid connected, 28.8kW solar power system located in central Manchester. Real-time measured parameters are used as inputs for the developed system. The proposed model and its control strategy offer a proper tool for smart grid performance optimization
FROM CHOCOLATE BARS TO MOTOR CARS: The separation seen from the perspective of goods trafficking between Israel and the West Bank (2007-2010)
This chapter analyses the change in the informal trafficking of standard consumer goods between Israel and the West Bank since summer 2007, when Palestinian Authority's security forces were redeployed under the supervision of General Dayton. Based on an examination of the trafficking and the strategies developed by the traffickers, the Palestinian Authority's capacity to territorialise its control in Palestinian enclaves will first be assessed. Changes in the nature of these transactions will then be studied to identify the new forms of regulation that are emerging between the Israeli and Palestinian economies, over and above formal exchanges
Geregelter Meßplatz für Sensoren zur invasiven Blutdruckmessung
Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich.This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.Der im vorliegenden Artikel vorgestellte neuartige Simulator ist ein kompletter Meßplatz für die Prüfung der gesamten Blutdruckmeßkette entsprechend den AAMI-Spezifikationen für alle gängigen medizinischen Drucksensoren. Mit Hilfe einer mikrocontrollergesteuerten Einheit werden gespeicherte technische Solldruckkurven einstellbarer Amplitude und Frequenz sowie physiologische Druckverläufe erzeugt und die Erfassung der Meßdaten vorgenommen. Über eine serielle Schnittstelle können darüber hinaus beliebige Solldruckkurven von und Meßdaten zu einem Personalcomputer übertragen und dort ausgewertet werden. Für möglichst realitätsnahe Messungen wurden zusätzlich ein Spülsystem sowie eine Flußsimulation implementiert
ADTH: Bounded Nodal Delay for Better Performance in Wireless Ad-hoc Networks
© 2018 Delay is an unavoidable factor that occurs within networks and may be exacerbated by the nature of wireless ad-hoc networks. Maintaining a manageable level of delay may be required to provide satisfactory performance for each of the nodes that form the network. The variability of IoT devices, topologies and network conditions demand that a standalone and scalable scheme be used. ADTH is first shown to accomplish this through simulations with the NS-2 network simulator. The scheme was then used with testbed implementation with Gumstix devices and real-time traffic provided by an STC Traffic Generator. These demonstrated its effectiveness in managing flows of delay sensitive traffic, in addition to delivering superior bandwidth utilisation than standard policies
Performance of Standard and Customized Search Interfaces
The research conducts a performance comparison between standard search interfaces available in modern search engines with a customized search interface that allows the user to change the way the information is presented on the screen. The tested hypothesis is that customized search interface results in a decrease in total search time and increase (or the same amount) of successful searches. Customizable options included font, background, help, tool tips, highlights, preview text and Boolean operators. Based on the performed study customized interfaces allowed users to increase the speed of obtaining correct search results by 10.2%. The benefit comes with a cost of time that users spend to configure the interface. Further research is recommended to both test the results on wider audiences, and test additional customization options
Beyond the border: narrating the journey of the Palestinian refugees in Jordan
This thesis intends to narrate the journey of Palestinian refugees, choosing Jordan as the study area. It will highlight the stages of the Palestinian journey from exile, displacement, the legal right to return to their homeland, and their lives as refugees in a different country.
With a focus on analyzing the tangible and intangible aspects of a Palestinian refugee camp in Jordan in light of its state of permanent temporariness; as it acts as a significant factor in the lives of the Palestinian refugees and their journey.
The temporary role of the refugee camps has caused an issue for the lack of certainty on how long this temporary state might persist, often it lasts longer than anticipated, and in the Palestinian case it has gone on for 74 years, which had negative impacts on the built environment of the refugee camps and the sense of identity.
The outcome of this thesis focuses on preserving the Palestinian journey and conserving a nation’s memory while raising awareness about the lives of millions of unfortunate individuals who were forced to flee their homeland to survive. It is also a personal notion of being a link between the author and his ancestral roots, being a Jordanian citizen from Palestinian roots
E-Recruitment & the effectiveness of the diffrernet means of internet as a recruitment source: A case study of five stars hotels in Qatar
The use of technology and internet has increased in the last few years in all fields. With the high competition in labor market to attract talents it was necessary for all organizations to enhance their recruitment process. The aim of this paper is to understand the effectiveness of the different means of internet as a recruitment source used by five stars hotels in Qatar and show if these hotels are benefiting from these tools to attract qualified applicants. It measures how company website, social media and recruitment websites are being effective to the hotels based on four factors. These factors are: quality of applicants, workload required, cost efficiency and geographical spread. The study adopted a multi-method approach combining literature review and a case study research using semi- structured interview. The results indicated that all five stars hotels and considered e-recruitment to be an effective tool. Company website is the most used method and most of the hotels link it to a recruitment website. Social media is not used by all of the hotels, for some of them it is not considered a professional method of recruitment. The study also includes some recommendations that can help the hotels to get the maximum benefits of e-recruitment
تأثير استخدام أنواع مختلفة من الأسمدة على نمو ونوعية الخس (Lactuca sativa L.)
The experiment was conducted during the period from March to the end of April 2019 to observe the effect of different fertilizer regimes on the growth, quality and yield of lettuce under field conditions. The experiment was consisting of four treatments as well as a control without fertilizer T1, compost T2, compost tea T3 and chemical fertilizer T4, in each treatment 50 replicates were planted. The measurements included wet and dry weight for shoot and root, plant length, and chlorophyll percentage. The study revealed that lettuce\u27s best growth values were obtained with the use of eco-friendly organic fertilizer accompanied by more than control one and chemical fertilizer. The average maximum length of plants after 60 days was recorded in T2 (42.3 cm) \u3e T3 (37.3 cm), T4 (35.9 cm) and \u3e T1 (23.8 cm). The results indicated that compost treated plant (T2 and tea compost T3) had highest chlorophyll content, i.e., 42.3 and 40.6%, respectively, as compared to chemical fertilizers T4 (37.3%) and the lowest chlorophyll content was in control T1 (30.9%). The values for wet shoot and root after 60 days were: 1575.2, 81.5 gm T2 \u3e 1367.6, 64.9 gm T3 \u3e 1251.1, 53.4 gm T4 and 612.1, 43.7 gm T1, respectively. The values for dry shoot and root after 60 days were: 131.5, 8.2 gm, T2 \u3e 112.7, 6.4 gm, T3 \u3e 101.9, 5.3 gm T4 and \u3e 51, 4.1 gm T1, respectively
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