Stable Infrastructure-based Routing for Intelligent Transportation Systems

Intelligent Transportation Systems (ITSs) have been instrumental in reshaping transportation towards safer roads, seamless logistics, and digital business-oriented services under the umbrella of smart city platforms. Undoubtedly, ITS applications will demand stable routing protocols that not only focus on Inter-Vehicle Communications but also on providing a fast, reliable and secure interface to the infrastructure. In this paper, we propose a novel stable infrastructure- based routing protocol for urban VANETs. It enables vehicles proactively to maintain fresh routes towards Road-Side Units (RSUs) while reactively discovering routes to nearby vehicles. It builds routes from highly stable connected intersections using a selection policy which uses a new intersection stability metric. Simulation experiments performed with accurate mobility and propagation models have confirmed the efficiency of the new protocol and its adaptability to continuously changing network status in the urban environment

Kerberos: Secure Single Sign-On Authentication Protocol Framework for Cloud Access Control

Cloud is a relatively new concept, so it is unsurprising that the security of information and data Protection concerns, network security and privacy still need to be addressed fully. The cloud allows clients to avoid hardware and software in Investments, gain flexibility, and cooperation with others, and to take advantage of sophisticated Services. However, security is a big problem for cloud clients especially access control; client profiles management and access services provided by public cloud environment. This article we are proposing an authentication model for cloud based on the Kerberos V5 protocol to provide single sign-on and to prevent against DDOS attacks in the access control system. This model could benefit by filtering against unauthorized access and to reduce the burden, computation and memory usage of cloud against authentication checks for each client. It acts as a trust third party between cloud servers and clients to allow secure access to cloud services. In this paper we will see some of the related work for cloud access control security issues and attacks. Then in next section we will discuss the proposed architecture

Family involvement and firm performance: Evidence from Saudi Arabia

Economies around the world are full of family businesses, the main and significant players in the growth of a nation. Saudi Arabia is no exception. As a result, family firm performance is considered as an important variable in the context of financial and management research. This study investigates the relationship between family involvement in ownership, management, control, and succession, as well as the presence of other blockholders on firm performance. Using longitudinal data from a panel of 38 non-financial Saudi family publiclisted companies (190 firm-year observations) from 2007 to 2011, and employing two different performance indicators (MBV and ROA), this study provides a sharp insight and deep understanding of the family firm characteristics and their influence on firm performance. The results provide strong evidence of the outperformance of family firms. However, when the non-linearity of family ownership is taken into account, the results become different; firm value decreases when family ownership increases from 0 to 31 per cent, and the relationship is positive beyond the 31 per cent level. Further, it is found that the positive impact of family ownership depends mainly on whether the CEO positions are occupied by the founders or not. In other words, founder CEOs play important roles in improving the firms' market and accounting performance. Family involvement on the board of directors is also found to be positively related to firm value, indicating that family directors are considered as stewards of the companies. Thus, they work for the benefit of the firms and the shareholders, In terms of the presence of other blockholders in ownership, this study documents its negative impact on market performance. In contrast, the presence of other blockholders in management positively influences firm accounting performance The results, in general, are statistically and methodologically robust

On the performance of broadcast algorithms in interconnection networks

Broadcast Communication is among the most primitive collective capabilities of any message passing network. Broadcast algorithms for the mesh have been widely reported in the literature. However, most existing algorithms have been studied within limited conditions, such as light traffic load and fixed network sizes. In other words, most of these algorithms have not been studied at different Quality of Service (QoS) levels. In contrast, this study examines the broadcast operation, taking into account the scalability, parallelism, a wide range of traffic loads through the propagation of broadcast messages. To the best of our knowledge, this study is the first to consider the issue of broadcast latency at both the network and node levels across different traffic loads. Results are shown from a comparative analysis confirming that the coded-path based broadcast algorithms exhibit superior performance characteristics over some existing algorithms

Feasibility studies for development of specific re-loadable binding sites for drug delivery systems immobilized onto implant surfaces

Ziel dieser Dissertation war die Entwicklung eines neuartigen biokompatiblen Beschichtungssystems für medizinische Implantatmaterialien, die Bindungsstellen für bioabbaubare, mit Wirkstoffen beladene Nanopartikel (Drug Carriers) tragen. Diese Wirkstoffe werden während des Abbaus der Drug Carriers dort kontrolliert freigesetzt. Nach dem Abbau der Partikel sind diese Bindungsstellen wieder frei um mit neuen Drug-Carriers beladen zu werden. Zum Erreichen dieses Ziels wurden als Testsystem die Implantatmaterialien Edelstahl und Zirkon-Keramik verwendet. Zur Verbesserung der Biokompatibilität wurde ein sogenanntes Passivcoating mit Polymeren wie z.B. dem medizinisch zugelassenen Polyethylenglykol (PEG) aufgebracht, um eine Schutzschicht zu bilden. Außerdem wurde ein geeignetes Rezeptorsystem zu verankert, das in der Lage ist, biodegradable mit Wirkstoffen beladene Mikro- oder Nanopartikel (Drug Carriers) zu binden, um eine lokale pharmakologische Wirkung zu erzielen (Aktives Coating). Zu diesem Zweck wurden spezielle Antikörper bzw. auch Antikörper-Fragmente als Capture-Moleküle an die Oberfläche des Implantatmaterials gebunden. Zur Herstellung der Drug Carriers wurden sowohl ein Copolymer aus Milch- und Glycolsäure (PLGA) als auch Chitosan verwendet. Die Drug Carriers werden dann entweder durch Hydrolyse oder mit Hilfe von Enzymen im Blut (Hydrolyse für PLGA, Lysozym für Chitosan) abgebaut und setzten die in ihnen enthaltenen Wirkstoffe lokal frei. Nach dem vollständigen Bioabbau liegen die Capture-Moleküle wieder frei vor und können mit neuen Drug Carriers beladen werden, womit ein vollkommen neuartiges System für Wirkstoffabgabe von medizinischen Implantaten zur Verfügung steht. Solche Beschichtungen können die Basis für eine Vielzahl von Anwendungen sein, die eine gezielte Wirkstoffabgabe an der Grenzfläche zwischen Implantat und gesundem Gewebe erfordern. Bei Bedarf können die Drug Carriers in die Blutbahn injiziert werden, binden an das Rezeptorsystem auf der Implantatoberfläche und setzen im Zuge ihres Abbaus die Wirkstoffe frei. Da sie mit unterschiedlichen Wirkstoffen beladen werden können, ermöglichen sie eine patientenspezifische Anpassung der Medikation, aber auch die Gabe von Wirkstoffen, die sonst zu rasch abbaubar oder schwierig zu dosieren wären. Der analytische Nachweis des erfolgreichen chemischen Setups mit Hilfe optischer Methoden erwies sich als schwierig auf Grund von Quenching Effekten im Fall von Metall bzw. wegen der rauen Oberfläche bei Zirkon (Keramik). Daher wurde die spezifische Bindung der Nanopartikel an der Implantatoberfläche an Glasoberflächen mit gleicher chemischer Beschichtung mit Hilfe von Fluoreszenzmikroskopie getestet. Außerdem mussten für den Nachweis des erfolgreichen chemischen Aufbaus und der biorecognitiven Bindung verschiedene neue analytische Tests entwickelt und evaluiert werden. Ein schwieriges Problem, das in dieser Arbeit gelöst werden musste, war das Finden eines brauchbaren Biorekognitionssystems für das Binden der biokompatiblen Drug Carrier Nanopartikel. Es braucht spezielle Lösungsansätze, um Antikörperbildung gegen biokompatible Materialien zu induzieren. Im Fall von Chitosan, waren Antikörper kommerziell erhältlich, während für PLGA ein sehr stringentes Immunisierungsprotokoll in Kaninchen entwickelt werden und auch Probleme hinsichtlich Reinigung und Titerbestimmung gelöst werden mussten. Durch die durchgeführten Experimente war es möglich ein „Proof of concept“ für ein wiederbeladbares Targeting-system zur lokalen Medikamentenfreisetzung an Oberflächen zu geben. Dieses neuartige System ist eine Basis für ein breites Anwendungsgebiet in der regenerativen Medizin wie z.B. Stents, artifizielle Knochenimplantate und andere künstliche Gewebe, die eine lokale und kontrollierte Medikamentenfreisetzung an der Grenzfläche zwischen Implantat und gesundem Gewebe benötigen. Das Drug-Delivery System schützt die eingeschlossenen Wirkstoffe vor vorzeitigem Abbau – wichtig z.B. bei Wachstumsfaktoren und Immunsuppressiva und erleichtert auch den Transport von schwer absorbierbaren oder schwer löslichen Wirkstoffen zum erwünschten Wirkort. Dank der hohen lokalen Wirkstoffkonzentration wird die Absorption schwerlöslicher Substanzen verbessert, wodurch unerwünschte systemische Nebenwirkungen vermindert werden können.The overall objective of this thesis is to develop novel, bio-compatible coatings for medical implant materials with binding sites for bio-degradable nanoparticles that may serve as drug carriers. The drugs are released gradually during decomposition and after particle degradation the binding sites can be reloaded with new drug delivering particles. To achieve this goal, we used stainless-steel and zirconia as test implant materials. To improve biocompatibility of these materials a so called “passive coating” procedure is used where biocompatible polymers such as polyethyleneglycol (PEG) act as a barrier. Furthermore a specific receptor system was introduced for binding drug containing biodegradable nano- or micro-particles to mediate local pharmacological activity, the so called active coating. For this purpose specific antibodies or antibody-fragments were generated and coupled to the implant material surface as capture molecules for the drug releasing particles. Poly (D,L-lactide-co-glycolide) (PLGA) and chitosan were used to produce these biodegradable nanoparticles. The particles are then degraded either by hydrolysis or by means of enzymes circulating in the bloodstream (mere hydrolysis for PLGA and lysozyme for chitosan) while releasing the drugs locally. After complete biodegradation the receptor system is then free again for reloading with new particles containing the respective drugs, making this a completely new mean of drug administration on medical implants. Such coatings can be the basis for a number of applications that require controlled, local drug delivery at the interface between an implant and healthy tissue. Upon the need for medication, drug-loaded nanoparticles can be injected into the bloodstream, bind to the particle-specific antibodies on the target implant and gradually release their drug content during degradation. As nanoparticles can be loaded with different drugs, this technology allows easy adjustment to patient-specific medication needs as well as the administration of compounds that are easily degradable or difficult to dose. Analytical proofs of principle on these materials have proved to be difficult, as the currently available optical methods for testing the successful chemical setup could not be applied because of quenching effects on metal surfaces and the rough surface of zirconia (ceramics). Therefore specific binding of the nanoparticles onto the implant surface was tested on glass substrates, coated similarly as the implant materials, by means of fluorescence microscopy. Furthermore for proof of the successful chemical setup and biorecognitive binding several new analytical test methods had to be developed and evaluated. One of the major challenges we had to overcome was to find suitable biorecognitive systems for binding of the drug containing particles, as these have to be biocompatible too. Special efforts were made to identify and generate specific antibodies against biocompatible materials. In case of chitosan, antibodies were commercially available, whereas for PLGA a very stringent immunisation protocol had to be developed for antibody production in rabbits, in addition to optimization of the purification and titer determination protocols. Using these tools, we were able to perform specific experiments that demonstrate a proof of concept for the possibility to generate a reloadable targeting device for local drug release and potential of our approach in targeted drug delivery and release. This new system provides the basis for a wide array of applications in regenerative medicine such as stents, implants of artificial bones and other artificial tissues, requiring local drug action at the interface between an implant and healthy tissue in a controlled manner. The delivery system protects the incorporated drugs from degradation prior to action e.g. growth factors and immunosuppressives, and facilitates the transport of poorly absorbable or insoluble drug candidates to the intended site of action. Due to the high local drug concentration, the absorption rate of poorly soluble drug molecules will be improved, which would significantly reduce undesired, adverse systemic effects. Furthermore after implantation also a change of drugs is possible, as with each reloading procedure appropriate drugs according to patients needs may be chosen

A Ten Year Descriptive Study of Adult Leukaemia at Al-Jomhori Teaching Hospital in Sana'a, Yemen

Background: There is scarcity of data of the epidemiology of leukaemia in Arab countries including Yemen. Understanding patterns of leukaemia underpins epidemiology and can provide insight into disease etiology. The aim of this research is to determine the epidemiologic pattern of adult leukaemia in Yemen.Methods: The research is a descriptive cross-sectional study. We analyzed the data of 702 adult patients with leukaemia, who were newly diagnosed over a ten-year period between October 1999 and October 2009 at the referral haematology centre in Sana’a at Al-Jomhori Teaching Hospital, according to type of leukaemia, age, sex, geographic distribution and time of diagnosis.Results: Acute Myeloid Leukaemia (AML) was found to be the most common (45.1%) followed by Chronic Myeloid Leukaemia (CML) (26.5%), Acute Lymphoid Leukaemia (ALL) (17.7%) and Chronic Lymphoid Leukaemia (CLL) (10.7%), respectively. There was an almost equal prevalence of AML and CML for males and females but males had significantly more cases of ALL and CLL (p =0.008). A significant variation in geographic pattern showed that the highest number of cases is seen the Central mountainous region and the least number of cases in the South-eastern region which is coastal and lowland (p<0.001). The seasonal variation showed that higher number of ALL cases was seen in the summer months (33%) compared with other seasons (21% in the spring, 24.2% in autumn and 21.8% in winter).Conclusions: The pattern of adult leukaemia in Yemen is different from that seen in western countries which could be attributed to different environmental exposure. The geographic pattern indicates a possible role of certain environmental factors which warrant further investigations. The pattern of seasonal variation needs further studies for evaluating the seasonality.

Hand and elbow gesture recognition based on electromyography signal

This project intends to analyze and classify the Electromyography (EMG) signal of muscles that is involved in certain hand and elbow gestures. The Electromyography (EMG) data acquisition protocol is then outlined and performed where the recorded Electromyography (EMG) signal corresponds with certain hand and elbow gestures. Therefore, four hand gestures were targeted, “hand contraction, forearm rotation, wrist extension and wrist flexion”. Thus, the EMG data that have been collected from 6 subjects are compared at a small demographic scale which is age and gender. Whereas, the EMG signals are collected using the software Lab-Chart 7 with 2 channel and 5 electrodes. The pre-processing of the EMG raw signals is presented using a 6th order Butterworth band pass filter, low and high pass filter with normalization. Furthermore, the features are evaluated using Variance (VAR), Standard Deviation (SD) and Root Mean Square (RMS) to test the significance of the features. Nevertheless, the K-Nearest Neighbour (KNN) classifier is used in order to classify the EMG signals for hand gestures. Lastly, the results from this project showed that the classifier has classified the gestures with a low performance due to the fewer amounts of the subjects and some other reasons

Composition and Characteristic of the Surficial Sediments in the Southern Corniche of Jeddah, Red Sea Coast

This work discusses the composition and characteristic of the surficial sediments in the southern corniche of Jeddah, Saudi Red Sea coast, in an attempt to infer the surficial distribution pattern of minerals and provenance of sediments. Twenty-six superficial sediments samples were collected from backreef and forereef areas and were analyzed for grain size, CaCO3 content, and mineralogy. The textural of grain size range from gravel to mud fraction. The mud-dominated substrates (<63 µm) occur generally in the back-reef area near the shoreline (sheltered area) and in the lagoon. Gravel rich-sediments are mostly found in forereef regions. The highest content of aragonite and Mg-calcite occur in the forereef area, probably because to suitability the forereef region for chemical and biochemical precipitation of these minerals. High Mg-calcite and Dolomite are low in both the regions. The pyrite occurs in lagoon; this indicates the reductive conditions in this part. However, on the contrary the percentage of carbonate minerals were low in the backreef-flat area, which could be attributed to the supply of non-carbonate terrigenous materials. The terrigenous material contains quartz, k-feldspar, plagioclase and amphibole minerals and are dominant in backreef-flat area with averages of 12.7%, 7.13%, 2.93% and 0.65%, respectively. Their abundance could be attributed to the supply of terrigenous materials by Aeolian deposits and intermittent Wadis

Adaptive Resource Allocation and Provisioning in Multi-Service Cloud Environments

In the current cloud business environment, the cloud provider (CP) can provide a means for offering the required quality of service (QoS) for multiple classes of clients. We consider the cloud market where various resources such as CPUs, memory, and storage in the form of Virtual Machine (VM) instances can be provisioned and then leased to clients with QoS guarantees. Unlike existing works, we propose a novel Service Level Agreement (SLA) framework for cloud computing, in which a price control parameter is used to meet QoS demands for all classes in the market. The framework uses reinforcement learning (RL) to derive a VM hiring policy that can adapt to changes in the system to guarantee the QoS for all client classes. These changes include: service cost, system capacity, and the demand for service. In exhibiting solutions, when the CP leases more VMs to a class of clients, the QoS is degraded for other classes due to an inadequate number of VMs. However, our approach integrates computing resources adaptation with service admission control based on the RL model. To the best of our knowledge, this study is the first attempt that facilitates this integration to enhance the CP's profit and avoid SLA violation. Numerical analysis stresses the ability of our approach to avoid SLA violation while maximizing the CP’s profit under varying cloud environment conditions