bluuebunny/crossref_metadata_2025 huggingface dataset:
Postoperative magnetic resonance imaging artifact with cobalt-chromium versus titanium spinal instrumentation
Authors: Ahmad Faiz U. , Sidani Charif , Fourzali Roberto , Wang Michael Y.
Published: September 2013

Object

Cobalt-chromium alloy (CoCr) rods haves some preferred biomechanical properties over titanium rods for spinal fixation. The use of CoCr rods in spinal fusion is relatively new, and there is no study in the existing world literature assessing the artifact caused by these rods in patients undergoing postoperative MRI. The purpose of this study is to compare the amount of imaging artifact caused by these implants and to assess its impact on the visualization of neighboring neural structures.

Methods

This study investigated MR images in patients who underwent implantation of thoracolumbar instrumentation using 5.5-mm-diameter CoCr rods between November 2009 and March 2011 and images obtained in a comparison group of patients who had 5.5-mm titanium rods implanted during the same time period. Axial measurements of the artifact created by the rods between the screw heads were compared between the groups. Two blinded board-certified radiologists performed the measurements independently. They scored the visualization of the spinal canal using a subjective scoring system of 1–3, with 1 representing very good visualization and 2 and 3 representing reduced (good or suboptimal, respectively) visualization as a result of rod-related artifact. All measurements and scores were independently provided for T1-weighted and T2-weighted fast spin echo sequences (1.5-T magnet, 5-mm slice thickness).

Results

A total of 40 levels from the CoCr group (6 patients) and 30 levels from the titanium group (9 patients) were included in the analysis. Visualization of the canal at all levels was rated a score of 1 (very good) by both evaluators for both the CoCr and titanium groups. The average artifact on T1-weighted images measured 11.8 ± 1.8 mm for the CoCr group and 8.5 ± 1.2 mm for the titanium group (p < 0.01). The corresponding measurements on T2-weighted images were 11.0 ± 2.3 mm and 8.3 ± 1.7 mm (p < 0.01), respectively. In a mixed regression model, the mean artifact measurement for the CoCr group was, on average, 3.5 mm larger than for the control group. There was no significant difference between the measurements of the 2 evaluators (p = 0.99).

Conclusions

The artifact caused by CoCr rods is approximately 3.5 mm larger than that caused by titanium rods on axial T1- and T2-weighted MRI. However, artifact from either CoCr or titanium was not found to interfere with the evaluation of the spinal canal and surrounding neural elements.
Pediatric spinal pilomyxoid astrocytoma
Authors: Garber Sarah T. , Bollo Robert J. , Riva-Cambrin Jay K.
Published: September 2013

Pediatric spinal pilomyxoid astrocytoma (PMA) is an extremely rare tumor that merits recognition as a specific, unique entity. The authors present the case of an intramedullary PMA in the thoracic spinal cord of an 11-year-old boy who presented with back pain, scoliosis, and multiple lung nodules. The patient underwent T5–11 laminoplasty and near-total resection of the spinal tumor. The final pathological diagnosis was WHO Grade II PMA. The patient did well for 14 months until the tumor progressed both clinically and radiographically. A literature review focusing on the clinical characteristics, histology, and treatment of PMAs provides a better understanding of these rare lesions. Because of the small number of cases optimal treatment guidelines have not been established, but gross-total resection and adjuvant chemotherapy with alkylating agents appear to confer a better long-term prognosis. Pediatric patients with PMAs can remain recurrence free at least 5 years after surgery, although these tumors may disseminate or dedifferentiate into more malignant gliomas. Recognition of intramedullary PMA as a unique entity in children is vital to the development of specific surgical and adjuvant treatment regimens.
IDENTIFYING AND ANALYSING UNDERLYING PROBLEMS OF SHIPBUILDING INDUSTRIES IN BANGLADESH
Authors: Iqbal K. Shahriar , Zakaria N. M. Golam , Hossain Kh. Akhter
Published: September 2013

­­­­Shipbuilding is considered to be a thrust sector in the economy of Bangladesh. But various problems are there to obstruct the development of this sector. This paper is aimed to identify the underlying problems and then analyze the nature of the problems to make it helpful overcoming the obstacles. A brief history and prospect of the shipbuilding industries in Bangladesh in the perspective of global scenario is also discussed.DOI: http://dx.doi.org/10.3329/jme.v41i2.7509
MHD NATURAL CONVECTION FLOW ALONG A VERTICAL WAVY SURFACE IN PRESENCE OF HEAT GENERATION/ABSORPTION WITH VISCOSITY DEPENDENT ON TEMPERATURE
Authors: Parveen N. , Alim M. A.
Published: September 2013

The present numerical simulation is analyzed the Magnetohydrodynamic natural convection flow andheat transfer along a uniformly heated vertical wavy surface in presence of heat generation/absorption withtemperature dependent variable viscosity. Using the appropriate transformations the governing boundary layerequations are reduced to non-dimensional forms. The resulting nonlinear system of partial differentialequations are mapped into the domain of a vertical flat plate and then solved numerically applying implicitfinite difference method together with Keller-box scheme. The solutions are expressed in terms of the skinfriction coefficient, the rate of heat transfer, the streamlines as well as the isotherms over the whole boundarylayer. The implications of heat generation/absorption parameter (Q) and viscosity parameter (?) on the flowstructure and heat transfer characteristics are investigated in detail while, Prandtl number (Pr), magneticparameter (M) and the amplitude-to-length ratio of the wavy surface (?) are considered fixed. Comparison withpreviously published work is performed and is found to be in good agreement.DOI: http://dx.doi.org/10.3329/jme.v42i1.15944
PREPARATION OF CONDUCTING CARBON FROM RICE HUSK CHAR
Authors: Ahiduzzaman Md. , Islam A.K.M. Sadrul
Published: September 2013

Porous carbon materials have attracted interest recently as they are potential candidates for largenumber of applications especially in catalytic supports, battery electrodes, capacitors, gas storage and biomedicalengineering applications. As porous carbons are mostly amorphous in nature, a little presence of sp2 carbonstructure enhances the possibility of using these carbon materials for wider applications involving electricalconductivity. Electrical conductivity of in porous acitivated carbon is increased by doping a suitable metal ion. Ricehusk char is choosen in this study as precursor for preparation of conducting carbon. The produced conductingcarbon exibits p-type semiconductor in character when copper, nickle, zinc and silver ions are doped. The highestelectricaal conductivity of silver ion doped material is found to be 2.84x10-2 mho/cm at 60% of ion concentration ofdoping solution. The results of this study conclude that rice husk char could be used for producing conductingcarbon and silver ion is the better among other doping materials used.DOI: http://dx.doi.org/10.3329/jme.v43i1.15776
NUMERICAL ANALYSIS OF HEMODYNAMIC FORCES THROUGH STENOTIC ARTERY
Authors: Shahed Syeda Reham , Ali Mohammad , Islam Md. Quamrul
Published: September 2013

A numerical analysis is carried out to demonstrate the variation of two hemodynamic forces: wallshear stress and pressure in the flow field of stenotic artery. The artery has 75% stenosis severity withaxisymmetric cosine shaped stenosis. The wall of the vessel is considered to be rigid. A sinusoidal pulsatile flowis assumed as inlet boundary condition. During the simulation both standard k-? model of low Reynoldscorrection and standard k-? model are used. Some analysis with standard k-? model with low Reynoldscorrection show better agreement with previous experimental results. The peak wall shear stress is found to belocated proximal to the stenosis throat. The results from the standard k-? turbulence model illustratesoscillating wall shear stress downstream the stenosis throat throughout the time period. The pressure gradientat the throat is highest at peak flow condition. These factors contribute to further growth and rupture ofplaques.DOI: http://dx.doi.org/10.3329/jme.v43i1.15780
La barque sur le Neckar ou La barca en el Néckar
Authors: Cromphout Francis
Published: September 2013

Le corpus choisi pour notre étude sur la bilingualité en tant que facteur d'option stylistique est La barque sur le Neckar, le premier résultat littéraire du changement de langue d'Hector Bianciotti, ainsi que la traduction effectuée par la suite par ce même auteur. Nous inspirant de la théorie du dialogisme de Bakhtine nous avons émis l'hypothèse que ce changement de langue, auquel a dû correspondre un processus psychologique d'intériorisation, a pu se doubler de changements de nature stylistique, impliquant une autre vision en français et en espagnol. Partant de là nous avons fait une analyse comparative des deux versions. Etudiant les aspects problématiques de l'autobiographie fictive qu'est la nouvelle de Bianciotti, nous en avons dégagé le cadre fonctionnel, caractérisé par l'ambivalence entre discours et récit, nous permettant d'analyser les variantes dans le domaine morpho-syntaxique. Une analyse des omissions et des ajouts dans la traduction espagnole, ainsi qu'une analyse globale des options stylistiques, nous ont finalement permis de confirmer notre hypothèse première.
Le Brésil dans la bande dessinée de Gérard Lauzier
Authors: Guméry-Emery Claude
Published: September 2013

Gérard Lauzier a vécu six années au Brésil, où il a collaboré à plusieurs journaux. Quand il est rentré en France, il en a rapporté une connaissance profonde du pays et du peuple brésilien, que l'on découvre au long de sa production de bandes dessinées. Dans un premier temps il se contente d'allusions d'initiés à travers les patronymes de ses personnages et certains toponymes, puis il montre comment est vu le Brésil par les classes aisées de Paris, et enfin il donne sa pleine mesure en décrivant le petit peuple brésilien dans les « Chroniques de l'Ile Grande », une île paradisiaque du Recôncavo babiano. Mais, malgré une transcription fidèle de la réalité, sa vision correspond le plus souvent aux clichés que les Européens ont dans la tête...
Intelectuais franceses e brasileiros : verso e reverso
Authors: Da Costa Lamartine P.
Published: September 2013

O autor toma análises de escritores franceses sobre a realidade brasileira, ressaltando a questão da procura da identidade nacional por parte dos intelectuais brasileiros.
Un rendez-vous manqué : le voyage d'Albert Camus en Amérique du Sud (1949)
Authors: Andreu Jean-L
Published: September 2013

A l'occasion d'une tournée de conférences qu'il effectue en Amérique du Sud (Brésil, Uruguay, Argentine, Chili), en 1949, Albert Camus tient un journal où il note ses impressions. Pour des raisons de manque de disponibilité, d'incommunication et de maladie, l'image qu'il nous propose de l'Amérique, dont il devrait se sentir très proche, prend la forme d'un rendez- vous manqué.
ἀφίκτωρ, Eschyle, Suppliantes 1 et 241
Authors: Dobias-Lalou Catherine
Published: September 2013

Le mot άφίκτωρ est un quasi-hapax auquel on prête en général, avec le scholiaste, deux sens : épithète de Zeus en Suppl. 1, il signifierait « protecteur des suppliants » ; le pluriel au v. 241 désignerait « les suppliants » en général. Écartant la solution qui unifierait les sens en faisant de Zeus lui-même un suppliant, on peut proposer une nouvelle interprétation rendant tout son sens au préverbe et au morphème de nom d'agent. Des inscriptions de Cyrène et de Lindos font connaître, à l'actif et au passif, le verbe ἀφικετεύω « sortir de l'état de supplication, réintégrer dans une communauté civique », tandis qu'à Cnide le rituel est décrit comme ἀφικετεια. On en déduit que Zeus est invoqué comme « celui qui réintègre les suppliants » (v. 1) et que le pluriel du v. 241 désigne l'ensemble des θεοί ἀγώνιοι qui, avec Zeus, vont participer à cette délivrance. L'intervention « poétique » d'Eschyle doit consister en deux traits archaïques, l'emploi de la base ίκ- au lieu d'ίκετευ- et le recours au suffixe -τωρ.
Damage of polyesters by the atmospheric free radical oxidant NO3•: a product study involving model systems
Authors: Goeschen Catrin , Wille Uta
Published: September 2013

Manufactured polymer materials are used in increasingly demanding applications, but their lifetime is strongly influenced by environmental conditions. In particular, weathering and ageing leads to dramatic changes in the properties of the polymers, which results in decreased service life and limited usage. Despite the heavy reliance of our society on polymers, the mechanism of their degradation upon exposure to environmental oxidants is barely understood. In this work, model systems of important structural motifs in commercial high-performing polyesters were used to study the reaction with the night-time free radical oxidant NO3• in the absence and presence of other radical and non-radical oxidants. Identification of the products revealed ‘hot spots’ in polyesters that are particularly vulnerable to attack by NO3• and insight into the mechanism of oxidative damage by this environmentally important radical. It is suggested that both intermediates as well as products of these reactions are potentially capable of promoting further degradation processes in polyesters under environmental conditions.
Structure elucidation of β-cyclodextrin–xylazine complex by a combination of quantitative 1H–1H ROESY and molecular dynamics studies
Authors: Ali Syed Mashhood , Fatma Kehkeshan , Dhokale Snehal
Published: September 2013

The complexation of xylazine with β-cyclodextrin was studied in aqueous medium. 1H NMR titrations confirmed the formation of a 1:1 inclusion complex. A ROESY spectrum was recorded with long mixing time which contained TOCSY artifacts. It only confirmed the presence of xylazine aromatic ring in the β-cyclodextrin cavity. No information regarding the mode of penetration, from the wide or narrow side, could be obtained. We calculated the peak intensity ratio from the inter-proton distances for the most stable conformations obtained by molecular dynamics studies in vacuum. The results show that highly accurate structural information can be deduced efficiently by the combined use of quantitative ROESY and molecular dynamics analysis. On the other hand, a ROESY spectrum with no spin diffusion can only compliment an averaged ensemble conformation obtained by molecular dynamics which is generally considered ambiguous.
CUSTOMER SEGMENTATION IN PRIVATE BANKING SECTOR USING MACHINE LEARNING TECHNIQUES
Authors: Smeureanu Ion , Ruxanda Gheorghe , Badea Laura Maria
Published: September 2013

Machine learning techniques have proven good performance in classification matters of all kinds: medical diagnosis, character recognition, credit default and fraud prediction, and also foreign exchange market prognosis. Customer segmentation in private banking sector is an important step for profitable business development, enabling financial institutions to address their products and services to homogeneous classes of customers. This paper approaches two of the most popular machine learning techniques, Neural Networks and Support Vector Machines, and describes how each of these perform in a segmentation process.
THE DETERMINATION OF RENTS IN SHOPPING CENTERS DURING RECESSION PERIOD IN LITHUANIA
Authors: Raslanas Saulius , Lukošienė Indrė
Published: September 2013

This research examines how to relieve the economical pressure to the market of shopping centers by choosing one of the percentage rent forms. Retail rents have two rental components typically: base rent and overage rent, which is equal to some predetermined percentage on sales and is paid once the tenant reaches some level of sales. Both of these components are related to many factors which are considered in international practice. The determination of the percentage rents in Lithuania is much more complicated because the most important information about retail segments of the shopping centers (sales per square meter, gross leasable area and rental prices) is not publicly available. The goal of this research was to analyze the US experience and data that is available on percentage rent determination and to adapt it to the Lithuanian market by implementing required adjustments.
CONTAGION ACROSS REAL ESTATE AND EQUITY MARKETS DURING EUROPEAN SOVEREIGN DEBT CRISIS
Authors: Hui Eddie C. M. , Chan Ka Kwan Kevin
Published: September 2013

Standard methods of testing contagion may not work well if the data set is not normally distributed. To cope with this problem, Hatemi-J and Hacker (2005) proposed a new case-resampling bootstrap method to test contagion. In this paper, we extend this method to test the parameters in the Forbes-Rigobon multivariate (FRM) test. The new method has the advantage that the bivariate model is extended to a multivariate framework which jointly models and tests all combinations of contagious linkages. We apply our method to investigate contagion across equity and real estate markets of four countries: Greece, U.K., U.S. and Hong Kong, during the European sovereign debt crisis, and compare the result with that by performing the FRM test directly. Two important results are found. Firstly, both tests we use give similar p-values of the coefficients which indicate the significance of contagion. Secondly, for both tests, the contagion pattern in the equity and real estate markets are different. Our study has an implication to investors that they should regularly review their portfolio and be aware of contagion triggered by a crisis. This would help them reduce their loss and is useful in strategic property management.
Innovation de rupture : concept fondamental ou slogan creux ?
Authors: Villon de Benveniste Guillaume
Published: September 2013

Au-delà des slogans et des modes, l’innovation de rupture est une nécessité au triple niveau de l’entreprise, de l’industrie et de l’économie nationale. Mais pour éviter l’échec, il faut avant tout en comprendre les mécanismes et distinguer deux types d’innovation de rupture : la rupture par le bas et la rupture par le haut.
L'hégémonie anachronique du PIB
Authors: Besançon Yves
Published: September 2013

On ne saurait trop rappeler aux décideurs publics que la nuance subtile entre croissance du produit intérieur brut (PIB) et progression du bien-être ne date pas d’hier. L’inventeur du PIB, Simon Kuznets, prévenait déjà en 1934 que « la mesure du revenu national peut difficilement servir à évaluer le bien-être d’une nation ». Dans un contexte de poursuite de la croissance du PIB par habitant, la double crise de l’écosystème et des inégalités économiques et sociales qui s’est ouverte depuis une trentaine d’années, soulignant de façon flagrante les limites conceptuelles et méthodologiques du PIB comme agrégat de mesure du « bonheur » dans nos sociétés d’opulence, n’a pourtant pas remis en cause la place importante qu’il occupe dans le discours politique et la conduite de la politique économique. Et pourtant celle-ci est presque anachronique au regard, d’une part, d’une réflexion déjà bien engagée sur la construction de nouveaux indicateurs complémentaires ou alternatifs au PIB et, d’autre part, d’une légitimité renforcée des thèses contestant la soutenabilité de sa croissance dans la logique du modèle libéral-productiviste qui a marqué les deux derniers siècles depuis le début de la première révolution industrielle.
La politique monétaire à la croisée des chemins
Authors: Anota Martin
Published: September 2013

La crise mondiale a ébranlé beaucoup de certitudes concernant le fonctionnement de l’économie et les politiques économiques. Avant qu’elle éclate, les banquiers centraux pensaient n’avoir qu’un seul objectif et qu’un instrument à leur disposition. Avec l’assouplissement quantitatif aux États-Unis ou encore la récente expérience monétaire au Japon, les autorités monétaires innovent et se dotent déjà de nouveaux outils. Surtout, elles sont susceptibles de modifier leur mandat afin d’éviter que l’épisode de la Grande Récession ne se reproduise. Plusieurs propositions ont été avancées pour redéfinir les objectifs de la politique monétaire...
6. Qu'est-ce que le travail d'accompagnement des chômeurs ?
Authors: Demazière Didier
Published: September 2013

Les conseillers professionnels du service public de l’emploi forment la ligne de front du traitement du chômage. Cet article rend compte de la tension dans laquelle ces conseillers travaillent : leur mandat est de plus en plus difficile du fait du niveau élevé de chômage, et il est aussi plus impératif du fait de la montée du pilotage par les résultats. L’attention portée au travail concret conduit à souligner la complexité de l’activité d’accompagnement vers l’emploi et les dilemmes éthiques qu’elle fait surgir : ce travail n’est pas seulement une activité relationnelle, impliquant des négociations avec les chômeurs, il est aussi indissociable de jugements interprétatifs portés sur la situation des chômeurs.
Influence of meteorological variables to water quality in five lakes over the Aggtelek (Hungary) and Slovak karst regions – a case study
Authors: Samu Andrea , Csépe Zoltán , Bárány-Kevei Ilona
Published: September 2013

The main objective of this study is to analyse the effect of tendencies in the meteorological variables on the water quality on the example of five lakes in the Aggtelek and Slovak karst. The data set used eleven water quality parameters (oxygen saturation, chemical oxygen demand, nitrate, nitrite, orthophosphate, total phosphorus, ammonium, pH, conductivity, iron, manganese), as well as daily data of six climatic parameters from the period 2008-2010. A cluster analysis is performed in order to determine the climate impact on the water quality parameters. Furthermore, factor analysis with special transformation, as a novelty in the study, is implemented to find out the weight of the climate parameters as explanatory variables and hence their rank of importance in forming the given water quality parameter as an influencing variable. The study introduces a methodology for analysing the climate impact on the water quality parameters. In order to reduce the number of the water quality parameters, a so called two-stage factor analysis was performed, which is a novel procedure. Application of the two-stage factor analysis involves both benefits and disadvantages. Its benefit is that it substantially reduces the number of resultant variables. In this way, information loss of the retained factors is around 20%. As a result, we received that both positive and negative extreme values of water quality parameters can be associated with weak or breaking-up warm fronts passing through over the region. On the contrary, the role of anticyclones or anticyclone ridge weather situations is supposed to be irrelevant. Unstable and extreme weather conditions act in the direction of breaking up the balance that would support the good water quality. This process does not benefit the water use nor the sensitive karst hydrogeological system.
Interpretation of hydrogeological functioning of a high karst plateau using the KARSYS approach: the case of Trnovsko-Banjška planota (Slovenia)
Authors: Turk Janez , Malard Arnauld , Jeannin Pierre-Yves , Vouillamoz Jonathan , Masini Jean , Petrič Metka , Gabrovšek Franci , Ravbar Nataša , Slabe Tadej
Published: September 2013

The high karst plateau of Trnovsko-Banjška planota is one of the most important reservoirs of karst water in Slovenia. Almost all important karst springs in this area are captured for water supply. A sustainable management of this source of groundwater is of strategic importance, not only as drinking water supply but also for the economy. For these reasons, many hydrogeological monitoring studies have been carried out over the last decades. However, no consistent regional overview of the hydrogeological functioning of Trnovsko-Banjška planota was available and we decided to study this area with more direct approach based on 3D geological and hydrogeological models. The so called KARSYS approach was developed in Switzerland and applied primarily to characterize groundwater reserves within a karst massif, and to sketch the main flow-paths carrying groundwater from recharge areas to the respective springs. The delineation of spring catchment areas in karst regions was better defined and interactions between catchments were interpreted. These results can be used to improve the management of karst waters in the studied area.
A comparison of tensile, fracture and fatigue mechanical behaviour of structural reinforcing bars made with different steels
Authors: Rodríguez C. , Belzunce F. J. , Canteli A. F.
Published: September 2013

The use of austenitic stainless steels as rebar is an option increasingly used in reinforced concrete structures exposed to aggressive environments and especially those that have to work in marine environments. The same is true for duplex stainless steel rebars, although nowadays they have a lower use, mainly due to the fact that their inclusion in the reinforced concrete standards was delayed 10 years compared to austenitic stainless steel ones, and consequently their in-service behavior is not as well known.

A study of the mechanical properties, including fracture toughness, fatigue behaviour and corrosion resistance in saline alkaline environments of austenitic (AISI 304LN and 316LN) and duplex (D2205) stainless steel reinforcing bars was performed in this work. Bars made on a high ductility carbon steel (B500SD) that are normally used to reinforce concrete were also characterized and used as a comparison. Stainless steel reinforcing bars show mechanical properties at least similar but usually higher than one of the best carbon steel re-bars (B500SD), along with a significantly higher ductility and, of course, much better corrosion behaviour in saline alkaline environments.
The Effect of Knowledge Transfer Motivation, Receiver Capability, and Motivation on Organizational Performance
Authors: Bloodgood James M. , Chilton Michael A. , Bloodgood Thomas C.
Published: September 2013

Possessing knowledge resources is insufficient for organizational success. To achieve a competitive advantage, organizations need to be able to transfer knowledge from where it exists to where it is needed within the organization. This chapter examines the importance of motivation and capability of the sender and the receiver in knowledge transfer success in organizations. The Awareness, Motivation, Capability (AMC) perspective is used as a basis for explaining how various individual and organizational factors influence knowledge transfer. These factors are built into a knowledge transfer model that shows the relationship among them. Recommendations are made to provide managers with actions they can take at the individual and organizational levels to implement successful knowledge transfer practices within their organizations.
A Method for Assessing Knowledge Loss Risk with Departing Personnel
Authors: Jennex Murray E.
Published: September 2013

Knowledge workers hold much of an organization’s knowledge. Unfortunately, these knowledge workers tend to be transient, and when they leave, they take the knowledge inside them. Organizations need to try to capture this knowledge but find it difficult as it is usually too late to capture this knowledge when a worker announces he/she is leaving. This chapter presents a process for assessing each worker for the risk of taking knowledge with them. The purpose of this process is to aid organizations in allocating resources to capturing the most valuable and most accessible of the knowledge potentially being lost in time for it to be captured and retained.
Introduction to Mobile and Wireless Communications Networks
Authors: Rawat Danda B. , Bista Bhed Bahadur , Yan Gongjun
Published: September 2013

Wireless communication networks offer transmission of signals, such as voice, data, and multimedia, without using wires, which is the crucial part of mobile communications. After successful deployment of wireless cellular networks in licensed bands and Wi-Fi networks in unlicensed bands, such as Industry, Scientific, and Medical (ISM) and Unlicensed National Information Infrastructure (UNII), over the last decade, several wireless networks, application, and services are emerging. Furthermore, wireless networks offer several advantages including mobility while getting service, scalability for further extension, reduced cost-of-ownership, and so on. However, there are some disadvantages and concerns, such as security, data rate, reliability, range, etc. The demand of ubiquitous communications is driving the development of wireless and mobile networks. Wireless communication is the fastest growing segment of the communication industry. This chapter provides the fundamentals of wireless and mobile networks and their advantages and disadvantages.
Physical Layer Security and Its Applications
Authors: Sharma Rajesh K.
Published: September 2013

This chapter provides a survey of physical layer security and key generation methods. This includes mainly an overview of ongoing research in physical layer security in the present and next generation communication networks. Although higher layer security mechanisms and protocols address wireless security challenges in large extent, more security vulnerabilities arise due to the increasingly pervasive existence of wireless communication devices. In this context, the focus of this chapter is mainly on physical layer security. Some security attacks in general are briefly reviewed. Models of physical layer security, information theoretic works, and key generation methods including quantization and reconciliation are discussed. Some latest developments for enhanced security like Multiple-Input Multiple-Output (MIMO) systems, reconfigurable antennas, and multiple relay systems are also presented. Finally, some existing and emerging application scenarios of physical layer security are discussed.
Misbehavior Detection in VANET
Authors: Jain Shefali , Mathuria Anish , Das Manik Lal
Published: September 2013

Vehicular Networks (VANETs) have received increased attention from researchers in recent years. VANETs facilitate various safety measures that help in controlling traffic and saving human lives. As VANETs consist of multiple entities, effective measures for VANET safety are to be addressed as per requirement. In this chapter, the authors review some existing schemes proposed for misbehavior detection. They categorize the schemes into two parts: data centric and non-data centric misbehaving detection. In data-centric misbehaving detection, the receiver believes the information rather than the source of the information. The authors compare schemes in each category with respect to their security strengths and weaknesses. The comparative results show that most of the schemes fail to address required security attributes that are essential for VANET safety.
Privacy Protection in Vehicular Ad-Hoc Networks
Authors: Yan Gongjun , Rawat Danda B. , Bista Bhed Bahadur , He Wu , Alnusair Awny
Published: September 2013

The first main contribution of this chapter is to take a non-trivial step towards providing a robust and scalable solution to privacy protection in vehicular networks. To promote scalability and robustness the authors employ two strategies. First, they view vehicular networks as consisting of non-overlapping subnetworks, each local to a geographic area referred to as a cell. Each cell has a server that maintains a list of pseudonyms that are valid for use in the cell. Each pseudonym has two components: the cell’s ID and a random number as host ID. Instead of issuing pseudonyms to vehicles proactively (as virtually all existing schemes do) the authors issue pseudonyms only to those vehicles that request them. This strategy is suggested by the fact that, in a typical scenario, only a fraction of the vehicles in an area will engage in communication with other vehicles and/or with the infrastructure and, therefore, do not need pseudonyms. The second main contribution is to model analytically the time-varying request for pseudonyms in a given cell. This is important for capacity planning purposes since it allows system managers to predict, by taking into account the time-varying attributes of the traffic, the probability that a given number of pseudonyms will be required at a certain time as well as the expected number of pseudonyms in use in a cell at a certain time. Empirical results obtained by detailed simulation confirm the accuracy of the authors’ analytical predictions.
Security Challenges in Wireless Sensor Network
Authors: Tripathi Meenakshi , Gaur M.S. , V.Laxmi
Published: September 2013

Wireless Sensor Networks are a subset of ad hoc networks. Their unique characteristics are smaller node size, high node density, unattended operation in remote areas. Dynamic topology and wireless communication make them vulnerable to numerous types of attacks. In addition to that, memory, processing, and energy constraint make it difficult to incorporate compute-intensive security solutions in these networks. Existing solutions for developing cost and energy efficient algorithms do not fit the security parameters for these resource constrained networks. As a result, these networks remain vulnerable to several types of attacks. This chapter presents a survey of various attacks at the different layers of WSN protocol stack, their detection, and countermeasures. Although every layer of the stack has its own security challenges, the network layer is most vulnerable to many security attacks because it provides an excellent basis for traffic monitoring activities, which helps the attacker form a strategy to perform the attack. The most common attacks on this layer are the Sybil attack, selective forwarding attack, wormhole attack, sinkhole attack, etc. This survey provides a comprehensive view of present attacking strategies to disrupt the normal functioning of WSN.
Seamless Mobility Management
Authors: Mitra Sulata
Published: September 2013

The next generation wireless networks will be heterogeneous wireless environments because of the coexistence of a large variety of wireless access technologies. The different networks have different architectures and protocols. So it is difficult for a user to roam from one radio system to another which can be solved by using the Internet protocol as a common interconnection protocol as it needs no assumptions about the characteristics of the underlying technologies. An all-IP wireless network is an IP-based wireless access system that makes wireless networks more robust, scalable, and cost effective. The nodes in such a network are mobile nodes as they change their location and point of attachment to the Internet frequently. The mobility management is an important research issue in an all-IP wireless network for providing seamless roaming facility to mobile nodes from one wireless system to another. The dynamic resource management is also required in this environment to ensure sufficient resource in the selected route for transmission or reception of the data packets during seamless roaming of the mobile nodes. This chapter is aimed at the researchers and the policy makers making them aware of the different means of mobility management and resource management for mobile nodes in all-IP wireless networks.
900MHz Spectrum Refarming Analysis for UMTS900 Deployment
Authors: Magar Chitra Singh Budhathoki
Published: September 2013

Refarming means re-arrangement of the traditionally allotted spectrum for a technology/application/service and carving out a part of the spectrum for technology/application/service with higher value. The refarming concept can be used for 3G network deployment in 2G bands or for 4G network deployment in 2G/3G bands. Relative to the UMTS core band (2100MHz), in the 900MHz band radio signal propagation loss is lower. Fewer base stations can be deployed in 900MHz band to achieve the same coverage. Especially in the rural areas, villages, etc., covering limited areas, the UMTS900 band coverage advantages are more obvious. The lower carrier frequency penetration capability becomes much stronger. It reduces the loss while penetrating the wall. This chapter aims to focus on the global UMTS900 refarming status, key advantages of UMTS900 refarming, major challenges of transitioning to UMTS900, technical feasibility of GSM/UMTS co-existence band, and UMTS900 frequency refarming case study in sandwich mode. ECC interference analysis and simulation results are provided for study on co-existence of GSM900 and UMTS900. In the later part of the chapter a detailed case study on 900MHz refarming on sandwich mode is provided with system simulation, frequency planning, capacity migration, and deployment strategy.
A Computer Network Attack Taxonomy and Ontology
Authors: van Heerden R. P. , Irwin B. , Burke I. D. , Leenen L.
Published: September 2013

Computer network attacks differ in the motivation of the entity behind the attack, the execution and the end result. The diversity of attacks has the consequence that no standard classification exists. The benefit of automated classification of attacks, means that an attack could be mitigated accordingly. The authors extend a previous, initial taxonomy of computer network attacks which forms the basis of a proposed network attack ontology in this paper. The objective of this ontology is to automate the classification of a network attack during its early stages. Most published taxonomies present an attack from either the attacker's or defender's point of view. The authors’ taxonomy presents both these points of view. The framework for an ontology was developed using a core class, the “Attack Scenario”, which can be used to characterize and classify computer network attacks.
Establishing Cyberspace Sovereignty
Authors: Barcomb Kris E. , Krill Dennis J. , Mills Robert F. , Saville Michael A.
Published: September 2013

International norms governing appropriate conduct in cyberspace are immature, leaving politicians, diplomats, and military authorities to grapple with the challenges of defending against and executing hostilities in cyberspace. Cyberspace is unlike the traditional physical domains where actions occur at specific geographic places and times. Rules governing conduct in the traditional domains emerged over centuries and share a common understanding of sovereignty that helps establish and justify the use of force. In cyberspace, sovereignty is a more abstract notion because the geographic boundaries are often difficult to define as data and applications increasingly reside in a virtual, global “cloud.” This paper proposes a construct for establishing sovereignty in cyberspace by studying similarities between space and cyberspace. The characteristics of the space domain challenged traditional notions of sovereignty based on geography. As nations deployed space-based capabilities, the concept of sovereignty needed to mature to deal with the physical realities of space. Sovereignty is defined, and general requirements for claiming sovereignty are presented. The evolution of sovereignty in space is then discussed, followed by a construct for how sovereignty could be defined in cyberspace. The paper also reviews U.S. civil policy and military doctrine and discusses how these documents offer insights into the U.S. approach to asserting its claims within these domains. It concludes by examining an emerging trend where nations not only seek to establish sovereign claims over the architectural aspects of cyberspace, but also the information that flows over it.
In Internet’s Way
Authors: Cohen-Almagor Raphael
Published: September 2013

The article is opened with definitions of terms utilized throughout the article. Terrorism is defined as the threat or employment of violence against noncombatant targets for political, religious, or ideological purposes by sub-national groups and/or clandestine individuals who are willing to justify all means to achieve their goals. Terrorist conduct is designed to attract attention to the terrorist’s cause and to spread fear and anxiety among wide circles of the targeted population. Subsequently the author analyses how terrorists use the Internet, and what can be done to counter their activities. The Internet is used to disseminate information, for propaganda, indoctrination, networking, psychological warfare, socialization, motivation, fund raising, spreading tactics, recruitment, planning activities and coordination. As the Internet became a major arena for modern terrorists, we need to devise appropriate methods to forestall their activities and establish security.
Information Therapy (Ix) and Information Prescription
Authors: Gavgani Vahideh Zarea , Shokraneh Farhad
Published: September 2013

To systematically review the observational and control trial evidence on information prescription and information therapy. The Cochrane Library and the medical databases of MEDLINE (1946 to10 April, 2012), and EMBASE (1974 to10 April, 2012) were searched with Ovid SP. The authors included only those studies that are related to the prescription of specific health information for specific patient as a complementary medicine. Therefore, they excluded the traditional patient education studies that are based on background information rather than being foreground, evidence- based and decision focused. The authors identified 232 papers and based on the criteria 34 full texts were screened and finally 18 were reviewed in this study systematically. Six papers were randomized control trials (RCTs) and 12 were observation studies. Most of the studies focused on satisfaction and knowledge as their primary outcomes. None of the studies examined the side effects of information intervention. Only one study focused on the health related primary outcomes and showed no significant change in pain and bowl movement (BMs) among children. This review found considerable research gaps in the study of information prescription outcomes. There is need for cohort studies and RCTs with rigorous control of confounding factors to figure out the impact of information prescription and information therapy on patient care.
Patients’ Medication Errors
Authors: Gavgani Vahideh Zarea , Oskouei Mina Mahami , Salehi Rezvanyieh
Published: September 2013

Patients’ awareness and informed involvement may reduce the prevalence of patients’ errors. The aim of this study is to identify the occurrence of patients’ medication errors in one of the leading tertiary care educational superspeciality hospitals in Iran during one year from October 2010 to October 2011. This is a retrospective study. Patients’ medical records were investigated to identify the reported errors in taking medication. A total of 140 medical records of patients who were hospitalized in Madani Heart Hospital of Tabriz University of Medical Sciences were investigated. Then the errors were categorized into three groups including: Reporting, Recklessness/ adherence, and Preference. Descriptive analysis was used to analyze data. Out of total 140 patients’ records, 16 (11%) patient medication errors were identified. Most of these errors were related to communication and reporting followed by non-adherence to the medication prescriptions. The least errors were related to patients’ preference. The study suggests that these errors could have been prevented by involving patients in decision making and self-care through information prescription.
Modeling Data for Enterprise Systems with Memories
Authors: Babaian Tamara , Lucas Wendy
Published: September 2013

Enterprise Resource Planning (ERP) systems are widely used but notoriously difficult to learn and master. The authors propose that a database approach to representing the system’s tasks, interface components, and usage logs in conjunction with the ERP domain data can serve as a foundation for improving system usability. The framework the authors designed supports automatic logging of user-system interactions and automated analysis of the logged data for enabling a variety of interface enhancements and assessments that can be performed dynamically by the system. Compared to existing work on usage logging, the authors’ framework expands the logging capabilities of ERP systems while providing a unifying basis for many different kinds of applications of log data.
Test Pair Selection for Test Case Prioritization in Regression Testing for WS-BPEL Programs
Authors: Mei Lijun , Cai Yan , Jia Changjiang , Jiang Bo , Chan W.K.
Published: September 2013

Many web services not only communicate through XML-based messages, but also may dynamically modify their behaviors by applying different interpretations on XML messages through updating the associated XML Schemas or XML-based interface specifications. Such artifacts are usually complex, allowing XML-based messages conforming to these specifications structurally complex. Testing should cost-effectively cover all scenarios. Test case prioritization is a dimension of regression testing that assures a program from unintended modifications by reordering the test cases within a test suite. However, many existing test case prioritization techniques for regression testing treat test cases of different complexity generically. In this paper, the authors exploit the insights on the structural similarity of XML-based artifacts between test cases in both static and dynamic dimensions, and propose a family of test case prioritization techniques that selects pairs of test case without replacement in turn. To the best of their knowledge, it is the first test case prioritization proposal that selects test case pairs for prioritization. The authors validate their techniques by a suite of benchmarks. The empirical results show that when incorporating all dimensions, some members of our technique family can be more effective than conventional coverage-based techniques.
3D Visualization of Filament Band Winding for Reinforced Plastics Manufacture
Authors: Fu Jian Hui , Yun Jae Deuk , Jung Yoong Ho
Published: September 2013

Filament winding simulation, an essential part of a CAD/CAM integrated system, helps the user to gain an intuitive understanding of the process of filament winding, the winding pattern, and laminate structure, and so find and solve potential problems before actual production. This speeds up the R&D cycle and reduces costs. To reduce costs, instead of winding several individually tensioned rovings, a band is usually wound. Thus, we present a band winding visualization system. The simulation system includes filament-path generation and graphic display of the band. In generating band paths, each filament path that constitutes a band path is produced from an initial fiber path based on geodesic equations. To imitate the band winding process more realistically, model display methods are used to deal with the graphic relationships among the different models, including the band model, mandrel model, and winding machine model. The simulation system can visualize the band laying process with the corresponding winder movement, and runs stably and reliably.
Contact Pressure of Loose-Fitted Tyre under Intermittent Contact
Authors: Yang Xiao Yan , Xiao You Gang , Lei Xian Ming , Chen Guo Xin
Published: September 2013

The total loads between kiln support are transmitted to the shell cross-section at tyre as shearing forces. According to the character and the condition of shell deformation and force balance, the mathematical models of contact pressure have been set up between tyre and shell under intermittent contact. The contact zones and contact pressures between tyre and shell are solved when the support reactions and gaps are variable. The results show the contact pressures increase with the increase of support reactions and gaps, the contact zones are proportional to support reactions, and inversely proportional to the gaps, which provide the reason for sound axis alignment and gap design.