bluuebunny/crossref_metadata_2025 huggingface dataset:
ANALISA KEAUSAN DISC BESI COR DENGAN METODE MATEMATIKA SEDERHANA MENGGUNAKAN TRIBOMETER PIN-ON-DISC TANPA PELUMAS
Authors: Syafa’at Imam , Khalim Abdul , Darmanto Darmanto
Published: September 2019

Semakin maju dan berkembangnya ilmu pengetahuan dan teknologi di bidang mechanical engineering khususnya di bidang tribologi, maka akan semakin banyak terungkap faktor-faktor yang dapat mempengaruhi umur pemakaian  komponen dari sebuah mesin. Besi cor adalah salah satu bahan untuk membuat komponen dari suatu mesin. Penelitian kali ini menggunakan tribometer pin-on-disc dengan besi cor A (79.5 HRB), besi cor B (82 HRB) dan besi cor A (86.5 HRB) sebagai disc dan bola baja AISI 52100 berdiameter 8,0 mm dengan kekerasan 60 HRC sebagai pin. Penelitian ini bertujuan untuk mengetahui pengaruh penggunaan material disc dan ukuran diameter pin terhadap nilai lebar kontak keausan, koefisien keausan berdimensi, volume dan tinggi keausan yang terjadi pada besi cor. Kajian juga membandingkan hasil keausan dengan berbagai model yang yang telah ada sebelumnya. Analisa perhitungan menggunakan penurunan geometri berdasarkan rumus matematika dasar sederhana dan menggunakan metode penurunan persamaan Archard. Hasil penelitian menunjukkan bahwa lebar kontak keausan, koefisien keausan berdimensi (KD), ketinggian keausan (h) dan volume keausan (V) mempunyai hubungan berbalik nilai dengan kekerasan material dan senilai dengan jarak sliding (s). Ukuran diameter pin mempunyai hubungan sebanding dengan lebar kontak aus, koefisien keausan berdimensi (KD), ketinggian keausan (h) dan volume keausan (V). Semakin keras suatu material maka keausan yang terjadi akan semakin kecil.Kata kunci: keausan, besi cor, pin-on-disc, Archard, metode sederhana
The less experienced forensic pathologists led to errors in the autopsy of Kennedy's body and an inaccurate medico-legal report
Authors: Alfleesy Othman
Published: September 2019

Because the assassination of Kennedy was public opinion and from my view, it is an ethical issue, it is time for me to contribute with this scientific and medico-legal opinion (because my age at the assassination was 7 years old). According to the available information I found, nothing about the murder has been as controversial as the nature of Kennedy’s Injuries. Kennedy’s wounds have been a matter of continuing controversy in regard to their numbers, their directions, their nature and type (either entrance or exit). In most reports, all have mentioned that the injuries of Kennedy as follows: Kennedy’s head exploded, Kennedy died as a result of two gunshot wounds, Kennedy has a wound in his back and other in his neck (anterior side) [1]. In many opinions, the forensic pathologists have written about Kennedy’s assassination, on 22 Nov. 1963. These opinions in regard to Kennedy’s autopsy & report, unfortunately, were confused, contradictory, and often have a lot of professional (malpractice) and practical mistakes.
Off the Baryonic Tully–Fisher Relation: A Population of Baryon-dominated Ultra-diffuse Galaxies
Authors: Mancera Piña Pavel E. , Fraternali Filippo , Adams Elizabeth A. K. , Marasco Antonino , Oosterloo Tom , Oman Kyle A. , Leisman Lukas , di Teodoro Enrico M. , Posti Lorenzo , Battipaglia Michael , Cannon John M. , Gault Lexi , Haynes Martha P. , Janowiecki Steven , McAllan Elizabeth , Pagel Hannah J. , Reiter Kameron , Rhode Katherine L. , Salzer John J. , Smith Nicholas J.
Published: September 2019

We study the gas kinematics traced by the 21 cm emission of a sample of six H i-rich low surface brightness galaxies classified as ultra-diffuse galaxies (UDGs). Using the 3D kinematic modeling code 3DBarolo we derive robust circular velocities, revealing a startling feature: H i-rich UDGs are clear outliers from the baryonic Tully–Fisher relation, with circular velocities much lower than galaxies with similar baryonic mass. Notably, the baryon fraction of our UDG sample is consistent with the cosmological value: these UDGs are compatible with having no “missing baryons” within their virial radii. Moreover, the gravitational potential provided by the baryons is sufficient to account for the amplitude of the rotation curve out to the outermost measured point, contrary to other galaxies with similar circular velocities. We speculate that any formation scenario for these objects will require very inefficient feedback and a broad diversity in their inner dark matter content.
Precursor Wave Amplification by Ion–Electron Coupling through Wakefield in Relativistic Shocks
Authors: Iwamoto Masanori , Amano Takanobu , Hoshino Masahiro , Matsumoto Yosuke , Niemiec Jacek , Ligorini Arianna , Kobzar Oleh , Pohl Martin
Published: September 2019

We investigated electromagnetic precursor wave emission in relativistic shocks by using two-dimensional particle-in-cell simulations. We found that the wave amplitude is significantly enhanced by a positive feedback process associated with ion–electron coupling through the wakefields for high magnetization. The wakefields collapse during the nonlinear process of the parametric decay instability in the near-upstream region, where nonthermal electrons and ions are generated. The intense coherent emission and the particle acceleration may operate in high-energy astrophysical objects.
Des bébés et de l’anthropologie
Authors: Quirot Benoît
Published: September 2019

Ce texte d’ouverture à deux numéros successifs de la revue l’autre, consacrés à l’anthropologie du bébé est une invitation au dialogue entre disciplines. Partant du constat d’une rencontre longtemps empêchée, autour du « naître humain », entre ethnologie et psychanalyse, il montre et défend l’intérêt de reprendre le débat aujourd’hui. Et fait donc le pari d’une relance possible des questions suscitées par la façon dont les cultures se transmettent aux bébés… et se réinventent aussi dans ces derniers.
Le besoin des autres
Authors: Carbone Francesca , Sarot Adeline , Moro Marie Rose
Published: September 2019

L’article trait des aspects ambigus de la relation d’aide entre demandeurs d’asile et bénévoles en Italie. À l’aide de la méthode complémentariste, de l’approche transculturelle et situationnelle, nous montrons que l’ethnocentrisme et la violence symbolique ne concernent pas seulement le dispositif d’accueil officiel, mais ils caractérisent aussi certaines organisations qui proposent un accueil alternatif des migrants, fait « par le bas ». Si motivée par des raisons inconscientes, l’aide génère déséquilibres et limite l’émancipation des sujets.
Comment évaluer la sensibilité interculturelle ?
Authors: Teyssier Julien , El Sayed Valentin , Denoux Patrick
Published: September 2019

Cette note de recherche met en avant la difficulté de l’évaluation du rapport qu’un sujet entretient avec la différence culturelle et de la sensibilité interculturelle (Bennett 1986), en particulier. Dans le cadre d’une première étude, nous montrons la différence de niveau de la sensibilité interculturelle (SI) selon que la dimension affective ou cognitive soit activée chez l’individu confronté à la différence culturelle. Dans une seconde étude, nous avons mis à jour des faiblesses dans l’opérationnalisation méthodologique des tests actuels, notamment l’IDI de Hammer & al. (1998) ne prenant pas considération de la dimension affective de la SI. Ces investigations se concluent sur la nécessité de développer un test permettant l’évaluation conjointe des dimensions cognitive et affective de la SI.
De la « porte ouverte » aux menaces d’expulsion : la présence syrienne en Turquie
Authors: Daniş Didem
Published: September 2019

La Turquie est le pays qui compte le plus grand nombre de réfugiés syriens sur son sol (3,6 millions en 2019). Cet article vise à analyser la présence syrienne dans le pays entre 2011 et aujourd’hui, en nous focalisant sur les évolutions de la politique migratoire mise en œuvre à leur égard. L’objectif de cette contribution est de mettre en lumière les instabilités de la politique d’accueil envers les Syriens et d’analyser la façon dont ces fluctuations produisent des inégalités et des injustices parmi cette population en exil.
La complexité de l’inscription de l’immigré dans sa nouvelle société : un regard croisé de la banlieue parisienne à Istanbul
Authors: Poyraz Mustafa
Published: September 2019

Cet article, issu d’enquêtes de terrain de longue durée en banlieue parisienne et à Istanbul, a pour objectif de démontrer l’importance de la configuration des espaces sociaux dans le processus d’inscription de l’immigré dans sa société d’accueil, durant lequel celui-ci développe différentes stratégies à la fois pour survivre et pour construire un avenir possible. À travers des observations et des entretiens effectués en région parisienne ainsi que dans les quartiers périphériques d’Istanbul, nous mettons l’accent, d’une part, sur la connexion ou la déconnexion des espaces sociaux qui encourage ou décourage le développement des relations humaines et, d’autre part, sur la question de la proximité, voire de l’interdépendance des facteurs liés à la pauvreté, à l’urbain et à l’immigration. Par voie de comparaison, cet article montre les effets de la rationalisation et de la fragmentation des espaces sociaux sur la concentration et le confinement des immigrés dans la banlieue parisienne, tout en montrant comment l’existence de lieux interconnectés dans les quartiers d’Istanbul facilite, malgré toutes les difficultés cumulées, l’inscription des immigrés nouvellement arrivés, notamment syriens, dans le tissu urbain stambouliote.
Ceux qui n’ont pas pu passer : les naufragés réengloutis du cimetière de Doğançay (Izmir) ou la naissance d’un « menu monument » de l’indicible
Authors: Pérouse Jean-François
Published: September 2019

La tragédie ininterrompue des naufrages en mer Égée des embarcations de fortune bondées de candidats au passage en Europe est ici envisagée à travers la formation et la transformation d’un impossible lieu de mémoire, la section des « sans-personne » au sein du vaste cimetière métropolitain de Doğançay à Izmir (Turquie). Depuis 2014, à l’initiative de la mairie métropolitaine d’Izmir, y est enterrée une partie des victimes innombrables de ces tentatives de passage. Une portion infime de ces naufragés parvient à sortir de l’anonymat pour devenir sujets de recueillement.
L’exil de la jeunesse égyptienne à Istanbul
Authors: Gad Nouran
Published: September 2019

Istanbul, au cœur d’une région historiquement traversée par de multiples mouvements migratoires, symbolise le lieu de rencontre des migrations récentes en provenance des pays du Proche-Orient et du Moyen-Orient. De jeunes Égyptiens, largement touchés par les transitions politiques en Égypte depuis 2011, s’y sont récemment installés. Leurs trajectoires personnelles ainsi que leurs expériences migratoires sont marquées par les stigmates d’une multitude de questionnements identitaires réactivés par les « printemps arabes ». En choisissant de s’installer à Istanbul, qu’ils considèrent être « une ville musulmane moderne », cette génération de jeunes cherche à tourner la page d’une séquence récente. Cet article a pour objet principal de comprendre les particularités de cette migration et les rapports de diasporicités créés en exil. Il est alors question de la construction de nouveaux liens entre Égyptiens installés à Istanbul et des interactions entre ceux-ci et les populations d’autres nationalités qui sont présentes et plus visibles dans la ville.
Genèse d’une culture stratégique américaine autonome. Le prisme des Principles of War et de leur développement doctrinal
Authors: Zajec Olivier
Published: September 2019

La culture stratégique des États-Unis, influencée par Jomini plus que par tout autre théoricien, les a menés à développer une vision spécifique des « principes de la guerre », révélatrice de leur approche singulière des opérations et de l’emploi de la force dans les relations internationales. En décembre 1921, dans le règlement Troops Regulations 10-5, les Américains adoptent une première liste officielle de neuf principes : Objectif, Économie des forces, Offensive, Manœuvre, Unité de commandement, Sûreté, Masse, Surprise et Simplicité. Cette adoption se fait avec enthousiasme, sans doute parce qu’une telle liste normée correspond bien à une gestion scientifique – un management – de l’action de force. Par la suite, cette approche sera critiquée, interrogée et remise en perspective tant par les stratégistes civils les plus influents que par les officiers américains. Pourtant, en un siècle, la liste ne sera paradoxalement jamais modifiée. En revenant sur ces débats, de 1918 à nos jours, cet article propose une relecture de cette résilience conceptuelle paradoxale, en se penchant sur la culture stratégique propre à l’appareil militaire des États-Unis, et un héritage avec lequel l’armée américaine se prépare à affronter les défis opérationnels d’un xxi e  siècle incertain.
Le trop et le néant
Authors: Baldassarro Andrea
Published: September 2019

La difficulté de penser l’infini dérive du fait qu’il ne peut être entièrement appréhendé par la pensée humaine. Cependant on le retrouve dans l’expérience du sentiment océanique et dans l’extase mystique : il représente toujours un « reste » qui dépasse toute possibilité de compréhension mais précisément grâce à sa « négativité », c’est une source de différenciation et de création. On étudie l’hypothèse que la problématique des cas-limites soit à situer à la frontière entre psychose et mélancolie plutôt qu’entre psychose et névrose.
Une brèche sur le délire. L’ours et le cosmonaute
Authors: Baruch Clarisse
Published: September 2019

Les premières années du travail en face à face avec Martin sont marquées par l’image de l’ours dressé, montré par un bateleur du Moyen Âge, et la somnolence irrésistible qu’il engendre. Pas de délire apparent, une histoire construite : où est la psychose ? Mais progressivement, dans les murs solides qui le protègent de l’envahissement de la psychose, s’ouvre une brèche par laquelle l’on peut découvrir un univers infini, une galaxie désolée, violente, peuplées de planètes qui ne sont reliées entre elles que par l’attraction gravitationnelle. Martin est alors un cosmonaute, revêtu de son exosquelette, il dérive entre les astres en mettant toute son énergie à éviter d’être absorbé par tel ou tel soleil d’une chaleur absolue. L’apparition lors de la thérapie de rêves qui commencent à construire des représentations, des liaisons avec les affects est considérée comme une évolution de l’organisation psychique vers une réelle capacité fantasmatique.
Genius, cette étendue qui nous excède
Authors: Soulié Muriel
Published: September 2019

Le travail clinique du psychanalyste et les théories qu’il se forme à partir de ses expériences forgent peu à peu sa pensée clinique propre. Celle-ci ouvre l’espace analytique à un nouveau paradigme : l’axe fini/infini de la psyché, présent dans l’œuvre de Bion. Ce paradigme prend racine dans un monde indifférencié et s’élève à la vérité du sujet, un « au-delà de soi » qui transcende les limites du moi. Par son attention portée à l’intraduisible, le psychanalyste laisse place à ce qui l’excède, « sans mémoire ni désir », dans une passivité consentie à l’immanence des séances. La brève histoire clinique illustre en deçà des mots, un moment de césure dont la valeur esthétique produit un saisissement émotionnel, propice à la création.
Sur quelques spécificités de la psychanalyse en Israël
Authors: Benhamou Maxime
Published: September 2019

S’agissant des spécificités de la pratique psychanalytique en Israël, l’auteur repère quatre invariants extra-muros qui vont influer à divers degrés sur le cadre analytique, sur sa structure d’ensemble tout autant que sur la nature et la qualité de son contenu : l’invariant culturel, l’invariant du trauma de la Shoah, l’invariant de l’impact des guerres et l’invariant linguistique. Selon l’auteur, cet invariant linguistique spécifique à l’hébreu mériterait d’être plus amplement étudié par la psychanalyse.
Pourquoi la télépathie ? Discussion de l’article de Thomas Rabeyron, Renaud Evrard, Claudie Massicotte
Authors: Fejtö Kalyane
Published: September 2019

À partir de la lecture du texte de Patrick Rabeyron, Renaud Evrard, Claudie Massicotte, « “ Es gibt Gedankenübertragung ”  : Transfert de pensée et processus télépathiques en analyse » nous reviendrons sur le trajet qui a conduit Freud à reconnaître l’existence du transfert de pensée et à tenter d’élucider la nature de certains échanges qui s’effectuent hors des modes de communication habituels. Il nous semble ainsi que la question de l’existence de la télépathie pour Freud est le résultat d’une démarche épistémologique que nous tâcherons de mettre en évidence. Nous nous pencherons sur l’importance de la perception et de l’empathie dans ce processus afin d’interroger par la suite la place qu’y occupent le corps et l’investissement pulsionnel. Nous montrerons ainsi que l’importance du mécanisme de régression dont témoigne la télépathie ne doit pas amener à sous-estimer le rôle de la pulsion et du langage. Car le fondement pulsionnel du langage, en tant qu’il engage la sensorialité et la sexualité infantile, nous permet de penser l’articulation entre le langagier et l’infralangagier qui préside au phénomène télépathique.
Phono-rythmie dans l’hymne des racines (Empédocle, F. 6)
Authors: Perceau Sylvie
Published: September 2019

Afin d’en finir avec les lectures allégorisantes du F. 6 d’Empédocle qui identifient de manière conflictuelle les quatre éléments à des entités théologiques isolables, cette contribution en livre une analyse phono-rythmique qui se fonde sur le postulat de l’existence d’une langue hypo-phonique qui opère des associations infra-signifiantes. C’est dans cette langue qu’Empédocle exige de son destinataire de discerner de manière aurale les « racines » des choses, dans une écoute phono-rythmique. Empédocle est humnopolos, « tourneur d’hymnes » (F. 146, 1), comme Apollon musicien est homopolos « tourneur assimilateur » et, pour décrire des processus physiologiques ou cosmogoniques, il use d’une langue ritualisée où se superposent différents scenarii (« l’enlèvement de Perséphone », « le serment des dieux », « le chagrin de Perséphone », etc.). Il semble ainsi dénoncer les hiérogamies olympiennes caractérisées par la tromperie et la violence et leur opposer la figure sotériologique de Nêstis-Aphrodite.
Posterior Corneal Curvature Measurements With Peripheral Fitting Zones Before and After Myopic LASIK Using Orbscan II
Authors: Cheng Arthur C.K. , Ho Thomas , Rao Srinivas K. , Lau Silvania , Lam Dennis S.C.
Published: September 2019

Purpose

To compare pre- and postoperative posterior corneal curvature measurements in peripheral fitting zones using the Orbscan II topographer in patients undergoing myopic LASIK.

Methods

Retrospective analysis of preoperative and 3-month postoperative Orbscan II data of 194 eyes that underwent myopic LASIK at a university eye center. Posterior corneal power was estimated using the peripheral 7- to 10-mm fitting zones. The pre- and postoperative values were analyzed and compared.

Results

The mean difference in estimated preand postoperative power of the posterior cornea was −0.04±0.16 diopters (
P
<.01).

Conclusions

The difference in posterior corneal curvature measurement following myopic LASIK using the peripheral fitting zone with the Orbscan II, as compared to the preoperative values, is clinically insignificant. [
J Refract Surg.
2008;24:807–810.]
Comparison of the AcrySof IQ Aspheric Blue Light Filter and the AcrySof SA60AT Intraocular Lenses
Authors: Mester Ulrich , Kaymak Hakan
Published: September 2019

Purpose

The development of aspheric intraocular lenses (IOL) designed to compensate for the positive spherical aberration of the cornea has been shown to improve the image quality of pseudophakic eyes. This prospective clinical study compared an aspheric IOL with a blue light filter (AcrySof IQ) with its spherical platform—the SA60AT IOL with conventional optic.

Methods

After uneventful phacoemulsification, 42 and 20 eyes were implanted with the AcrySof IQ aspheric lens and the SA60AT, respectively. Six weeks after surgery, higher order aberrations, visual acuity, contrast sensitivity, depth of focus, pupil size, and corneal asphericity were assessed.

Results

Visual acuity was good with both IOLs. A significant difference was found regarding spherical aberration. Mean values of spherical aberration, calculated for a 5-mm pupil were 0.20±0.06 µm with the SA60AT and 0.04±0.05 µm with the AcrySof IQ lens. Contrast sensitivity was significantly superior in the AcrySof IQ group in 7 of 15 measurement conditions. Asphericity of the cornea proved to be correlated with postoperative ocular spherical aberration.

Conclusions

The aspheric optic design of the AcrySof IQ results in significant reduction of postoperative ocular spherical aberration and improved contrast vision. Measuring the corneal asphericity allows estimation of postoperative ocular spherical aberration. [
J Refract Surg.
2008;24:817–825.]
Multiphoton-mediated Corneal Flap Generation Using the 80 MHz Nanojoule Femtosecond Near-Infrared Laser
Authors: Wang Bao-Gui , Lohmann Chris P. , Riemann Iris , Schubert Harald , Halbhuber Karl-Juergen , König Karsten
Published: September 2019

Purpose

To evaluate whether corneal flaps can be generated by the 80 MHz near-infrared, intense nanojoule femtosecond laser based on multiphoton absorption.

Methods

A solid-state Ti:Sapphire femtosecond laser system was integrated in an inverted JenLab Femt-OCut laser scanning microscope. A diffraction-limited 40× objective was used to induce multiphoton ionization and plasma production. New Zealand albino rabbits and porcine eyes were used. Surgical outcomes were determined using frame and line scans with nanojoule pulses at a wavelength of 800 nm.

Results

Surgical performance was assessed by optical imaging, histology, and electron microscopy. No significant corneal turbidity was observed. Optical imaging and histological examinations detected virtually no perturbation in the surrounding tissue. Corneal flaps and stromal lenticules were generated. Wound repair of the unlifted flaps was observed up to 90 days postoperatively.

Conclusions

Surgical results and follow-up studies confirm that this femtosecond laser at nanojoule pulse energy is able to generate corneal flaps precisely, without causing visible collateral damage to the surrounding tissue or overlying epithelium. [
J Refract Surg
. 2008;24:833–839.]
Development of Unilateral Corneal Ectasia After PRK With Ipsilateral Preoperative Forme Fruste Keratoconus
Authors: Reznik Jacob , Salz James J. , Klimava Alena
Published: September 2019

Purpose

To describe clinical and topographic features of keratectasia after photorefractive keratectomy (PRK) in a patient with abnormal preoperative topography.

Methods

A 25-year-old man underwent uneventful bilateral PRK for moderate myopia of −5.75 −1.75 × 95 in the right eye and −7.50 −1.25 × 80 in the left eye with best spectacle-corrected visual acuity (BSCVA) of 20/25 in both eyes. Preoperative corneal thickness was 500 µm in the right eye and 460 µm in the left eye. The total calculated ablation depth was 70 µm in the right eye and 100 µm in the left eye. Preoperative corneal topography revealed forme fruste keratoconus in the right eye with an inferior-superior ratio of 4.

Results

Five years postoperatively, the patient developed unilateral inferior keratectasia in the right eye with refraction of +0.50 −5.50 × 90, BSCVA of 20/100, and central corneal thickness of 481 µm with inferior corneal thickness of 374 µm.

Conclusions

This case report adds to the growing body of evidence in the ophthalmic literature suggesting that patients with preoperative forme fruste keratoconus or early keratoconus may develop clinically significant progression of corneal ectasia after PRK. [
J Refract Surg
. 2008;24:843–847.]
“A Layered Model of Human Consciousness”
Authors: Drigas Athanasios S. , Karyotaki Maia
Published: September 2019

The human brain’s structure operates as a systemic whole with an absolute interdependence between its respective parts. Processes, such as information, consciousness, awareness, conscience depict humans’ layered consciousness state, but also the wholeness, coherence and continuity of human cognition. Awareness contains self-awareness, a fundamental metacognitive ability, through which individuals perceive the internal world of thoughts, reflect, imagine, feel emotions and daydream as well as external awareness, through which individuals perceive the outside world with the help of the five senses. Moreover, neuroplasticity and consciousness are bi-directionally connected; consciousness, on the one hand, is the result of the growing complexity of the brain connectivity and, on the other hand, neuroplasticity stems from reorganizing brain connections through learning activities. The conscious brain is in a perpetual state of learning and evolvement; it learns how to describe and re-describe its own functions and illustrates the ancient Greek word “Anthropos” meaning someone looking higher and higher above.
Chatter Investigation on Machining of Gray Cast Iron Considering the Damping Effect
Authors: Araujo Everton Ruggeri Silva , Pinheiro Giovanni De Souza , Junior João Álvaro Belo Pantoja , Neto Salomão Levy
Published: September 2019

In recent years, the study of chatter vibrations has been intensifying in the machining of materials. In this paper an investigation of this phenomena was conducted for gray cast iron (CGI). The chatter vibrations in machining process can considerably compromise the workpiece surface finish, tool wear and in some cases provide severe damage to the machine-tool. Thus there is an imminent need to expand the theory of chatter vibrations for the class of brittle materials. To analyze the vibrations of the process of machining and zones where the process is stable, and where it is unstable, the stability lobes diagram was used. This diagram is constructed at low speed cutting, where the phenomenon of damping arises. The damping is a crucial factor in the process, it increases system stability. This effect was considered in the formulation of chatter vibrations using the indentation model of Wu. For experimental validations the signals of cutting force were acquired and analysis was conducted in frequency domain to identify where the vibrations emerged allied with a roughness analysis of the workpiece. The results demonstrated perfectly the consequences of chatter vibrations in surface finish of grey cast iron and proved that the stability lobes diagram provides good results to detect these vibrations, determining the areas where the material removal should be avoid.
Some Investigation on DDOS Attack Models in Mobile Networks
Authors: D Yuvaraj , M Sivaram , Uvaze Ahamed A. Mohamed , S Nageswari
Published: September 2019

With advancements in device and communication technologies, there has been a great revolution in development of net gadgets and communication technologies like 4G, 5G etc., In parallel, there has also been a widespread increase in ways to illegally hack data available over the internet and tamper the services offered to the customer. Common attacks include spoofing, Phishing, fraudulent extraction of transaction information and customer details. There have been attacks to cause traffic congestion over the network by introducing artificial infection packets over the internet. Hence, there is a great necessity in research for defence mechanism against these attacks to ensure smooth and safe provision of services to customers. This paper investigates and elaborates the different types of attacks that may be incident on a system or a network, their features and attack mechanisms which provide useful insights into developing an attack resistant system. Almost all types of attacks have been discussed systematically in this research paper with special emphasis on distributed denial of service attacks.
An Approach to Implement Cryptographic Protocol Version Downgrade Within a Secure Internal Network: TLS 1.x to SSL
Authors: S Ganeshkumar , Govindaraju Elango
Published: September 2019

The end to end encryption of connections over the internet have evolved from SSL to TLS 1.3 over the years. Attacks have exposed vulnerabilities on each upgraded version of the cryptographic protocols used to secure connections over the internet. Organisations have to keep updating their web based applications to use the latest cryptographic protocol to ensure users are protected and feel comfortable using their web applications. But, the problem is that, web applications are not always standalone systems, there is usually a maze of systems that are integrated to provide services to the end user. The interactions between these systems happens within the controlled internal private network environment of the organisation. While only the front ending web application is visible to the end user. It is not often feasible to upgrade all internal systems to use the latest cryptographic protocol for internal interfaces/integration due to prohibitive cost of redevelopment and upgrades to infra and systems. Here we define an algorithm to setup internal & external firewalls to downgrade to a lower version of the cryptographic protocol (SSL) within the internal network for the integration/interfacing connections of internal systems while mandating the latest cryptographic protocol (TLS 1.x) for end user connections to the web application.
Online Language Learning
Authors: Tzirides Anastasia Olga
Published: September 2019

This chapter addresses two forces in contemporary societies. The first is that societies today are characterized by cultural and linguistic diversity and increasing human mobility. In this complex setting, language learning has acquired more significance, with the need to communicate worldwide. Secondly, our society is experiencing dramatic technological advancements, one of which pertains to online learning. In this era of ubiquitous learning, where the use of learning management systems, mobile applications, social networks, and other digital technologies can underpin learning, it is necessary to re-address language learning. This overview will categorize the types of online language learning tools and practices that are emerging and prevalent and it will analyze their instructional approaches in the use of the technology. Ιt will also focus on the digital learners that access them having as an ultimate goal to understand the characteristics and needs of the contemporary global, multilingual, and digital learners and how these can be addressed in the learning process.
MOOCs Learners
Authors: Amina Tabassum
Published: September 2019

Massive Open Online Courses (MOOCs) have brought online learning movement to the forefront of educational research, but one of the major critiques of this learning platform is the very low completion rate. This chapter not only highlights the factors that influence low completion but also interprets how incompletion can fulfill goals of enrollment. Self-motivation is identified as a key factor for success in online learning platforms. This chapter puts together a review of existing research on MOOC enrollment and completion and also explains how success can be defined in a broader way in online learning. Along with that it draws on examples of success through incompletion in MOOCs from a qualitative study on female MOOC users from South Asia. Findings suggest that users enroll into MOOCs with goals to complete but also with specific needs to fulfill. An in-depth analysis of the interviews highlights how women have utilized this platform for their personal, professional or academic development and self-improvement.
Artificial Intelligence Assisted Learning (AIAL) Blueprint
Authors: Dingli Alexiei , Caruana Montalto Lara
Published: September 2019

Education is facing various challenges at the moment and needs to be reinvented. Some of the methods used have been inspired by the industrial revolution when an assembly line one-size-fits-all approach was setup in schools. Today, teachers are struggling to manage the number of students in a class thus making the quality of teaching inconsistent. Furthermore, they have to deal with students having different abilities in the same class which makes it impossible to give each and every student the individual attention they deserve. Through the artificial intelligence assisted learning (AIAL) system, the authors believe that they can personalise the learning and thus free a lot of time for the teacher which can be used to focus on those students that are really in need. This will be done on a case by case basis, thus creating a fairer educational system which is personalized for the needs of each and every student which guarantees equity.
Legislators' Perceptions and Knowledge of the Athletic Training Profession: Specific Considerations for Secondary Schools
Authors: Pike Lacy Alicia M. , Eason Christianne M. , Stearns Rebecca L. , Tosakoon Sararat , Casa Douglas J.
Published: September 2019

Context

Legislation has played a role in advancing the athletic training profession and improving the health and safety of student-athletes. However, few researchers have examined state legislators' perceptions and awareness of the skills and qualifications accompanying the athletic trainer (AT) role.

Objective

To explore state legislators' perceptions of the athletic training profession and knowledge related to qualifications and responsibilities of ATs.

Design

Cross-sectional study.

Setting

Web-based questionnaire.

Patients or Other Participants

State legislators representing 34 states (N = 143; 67.13% male, 32.87% female). Their average age was 58.7 ± 11.7 years, and they had served 7.4 ± 6.9 years in their current role. A majority served as members of the state house or assembly (n = 98, 68.5%), and 31.5% served in the state senate.

Main Outcome Measure(s)

Quantitative data were analyzed using descriptive statistics. Spearman ρ correlations assessed relationships between perceptions and knowledge of the profession. Stepwise regression analysis determined predictors of knowledge and perceived value of athletic training. Qualitative data were analyzed inductively.

Results

Approximately 69% of respondents considered an AT to be a trusted source of medical information, and 16% considered an AT as the most appropriate individual to provide medical care to an injured athlete on a daily basis. Thirty percent of state legislators selected AT employed at the school as a top sports safety measure. Three themes emerged from the inductive analysis: (1) recognition of the prevention domain, (2) misconception of ATs as personal trainers or strength and conditioning coaches, and (3) lack of knowledge regarding ATs' educational requirements.

Conclusions

Legislators demonstrated limited knowledge of the AT profession. When legislator knowledge of AT qualifications and responsibilities was high, value of the AT profession also significantly improved. Future efforts should focus on enhancing legislators' knowledge to increase the value placed on the athletic training profession and improve health and safety for secondary school athletes.
Utilisation of eye and skin care, and social services among persons with albinism in Ulundi, KwaZulu-Natal, South Africa
Authors: Zungu Zuzile , Mashige Khathutshelo P.
Published: September 2019

Background: Knowledge of the utilisation of eye and skin care, and social services among persons with albinism is essential for planning intervention strategies for this group.Aim: The aim of this study was to determine the utilisation of eye and skin care, and social services among persons with albinism in the Ulundi Municipality of KwaZulu-Natal Province, South Africa.Setting: The Ulundi Municipality of KwaZulu-Natal, South Africa.Methods: The cross-sectional survey used a questionnaire to collect data from 21 participants living with albinism. Semi-structured face-to-face interviews were conducted in small peer groups.Results: The participants (n = 21; males 8 and females 13) were aged 4 to 60 years (mean = 24.5 ± 17.9 years). All participants reported that they had their eyes tested within the last two years by an optometrist and none by an ophthalmologist. Almost half (42.9%) had never used a low vision device, this being because of their non-availability (44.4%), financial constraints (33.3%) and lack of or poor awareness (22.2%). Participants reported wearing a wide-brimmed hat (47.6%), a combination of wide-brimmed-hats and sunglasses (33.3%) for eye protection and 19% reported using neither. All the participants reported that they used sunscreen with sun protection factor and 90.5% reported using long-sleeved shirts for skin protection. The majority (81%) of participants reported receiving the South African Social Security Agency (SASSA) social (visual disability) grant, with 85.7% knowing where the SASSA offices were located.Conclusion: Despite the poor use of low vision aids, the level of utilisation of eye and skin care, and other social services among participants was good.
Computation of optimal investment allocations in a sequential portfolio optimisation
Authors: Mavungu Masiala , Hurwitz Evan , Marwala Tshilidzi
Published: September 2019

Orientation: This article is related to Financial Risk Management, Investment Management and Portfolio Optimisation.Research purpose: The aim is to compute optimal investment allocations from one period to another.Motivation of the study: Financial market systems are governed by random behaviours expressing the complexity of the economy and the politics. Risk Measure and Management are current and major issues for financial market operators and attract the attention of researchers who develop suitable tools and methods to describe and control risk. In this article, financial risk management is considered for an investor operating in the financial market.Research approach/design and method: This research developed Mathematical Models to describe the problem and Computational Simulations to compute, summarise the results and show their reliabilities.Main findings: The results are the investments allocations stored, some tables and the related computational simulations. By going from period one to another, one can notice from the graphs that the portfolio risk is decreasing and the portfolio profit increasing.Practical/managerial implications: The approach used in this article shows a way of solving rigorously any linearly constrained quadratic optimisation problem and any constrained nonlinear problem. It gives the ability of transforming judiciously certain linearly constrained nonlinear programming problems into sequences of linearly constrained quadratic problems and solving them efficiently.Contributions/value-add: This article developed Mathematical Models and Matlab Computer Optimisation Programs to give Computational Simulations. It wrote Computer Programs for a fifth-order autoregressive model to forecast asset profits.
Assessing the relative appropriateness of the credit management policies of South African universities of technology
Authors: Maseko Gauda J. , Oberholzer Merwe , Middelberg Susanna L.
Published: September 2019

Orientation: The study explores credit management on the South African higher education landscape in the context of the institutional theory.Research purpose: To calculate a best practice frontier to assess the extent to which universities’ credit management policy as an institutional resource is appropriate for its environment.Motivation for the study: The study was undertaken to investigate how the institutional environment influences the development of formal university structures.Research design, approach and method: A parallel mixed-method research design was followed to collect both qualitative data and quantitative data: document analysis to assess five universities of technology’s credit management policies and quantitative data testing 1392 senior students’ perspectives on the credit management policies of these five universities of technology.Main findings: The lesson learnt from this study is that the more aggressive the credit management policy, the more the students rated it as appropriate (fair, understandable and accurate). Furthermore, contrary to extant literature, no evidence was found that a stringent or aggressive credit management policy is experienced as rigorous.Practical/managerial implications: Universities of technology may apply aggressive credit management policies without the fear that they will be perceived as rigorous.Contribution/value-add: Policymakers should note that students desire a credit management policy that: (1) is well communicated to them; (2) encourages them, by granting discounts, to do early settlements of debt; (3) is strictly implemented; and (4) is strict with regard to the collection and recovery of (deferred) debt.
Risk factors associated with the occurrence of Brucella canis seropositivity in dogs within selected provinces of South Africa
Authors: Oosthuizen Johan , Oguttu James W. , Etsebeth Charne , Gouws Werner F. , Fasina Folorunso O.
Published: September 2019

The growing population of free-roaming dogs in informal communities in South Africa may increasingly place humans at risk of possible zoonotic infections including, but not limited to, Brucella canis. Worldwide, the prevalence of B. canis infection has increased during the last two centuries, resulting in increased reports of dog and human infections. This study investigated the risk factors associated with B. canis infection in dogs in three predefined areas: Gauteng, the Eastern Cape and Western Cape provinces, of South Africa. Dogs aged 7 months and older presented to welfare organisations and breeders in the study areas were selected for sampling. A comprehensive questionnaire on dog ownership, general health and vaccination status was completed prior to sampling. One blood sample of 8 mL was collected aseptically per dog. Then, equal amounts (4 mL) were transferred to the different vacutainer tubes. The 2-mercaptoethanol-tube agglutination tests were used after validation. Fifty-two dogs out of the combined sample of 1191 dogs from the three study areas tested positive for B. canis, representing an overall occurrence of 4.4%. A binomial logistic regression model was fitted to identify risk factors associated with B. canis in dogs within the study areas. Dog age (0.371; p 0.05) and external parasite infestation (0.311; p 0.05) were significantly associated with the B. canis infection. Ownership and sterilisation need to be further investigated as possible risk factors because both had odds ratios of 1684 and 1107, respectively, in the univariate model.
Dynamically exotic contact spheres in dimensions $\geq 7$
Authors: Alves Marcelo R.R. , Meiwes Matthias
Published: September 2019

We exhibit the first examples of contact structures on

S^{2n-1}

with

n\geq 4

and on

S^3\times S^2

, all equipped with their standard smooth structures, for which every Reeb flow has positive topological entropy. As a new technical tool for the study of the volume growth of Reeb flows we introduce the notion of algebraic growth of wrapped Floer homology. Its power stems from its stability under several geometric operations on Liouville domains.
Gender Differences in Program Factors Important to Applicants When Evaluating Orthopaedic Surgery Residency Programs
Authors: Kroin Ellen , Garbarski Dana , Shimomura Aoi , Romano Joseph , Schiff Adam , Wu Karen
Published: September 2019

Background

Despite specialty-driven efforts to improve diversity in the field, few women apply to orthopaedic residency, and women are unevenly distributed among programs. There is little evidence-based information on factors that may attract female applicants.

Objective

This study aims to identify factors important to applicants when evaluating orthopaedic residency programs and to identify gender-specific differences.

Methods

All applicants to a single orthopaedic surgery residency program in the 2017 Match were asked to fill out an anonymous survey. Respondents rated the importance of 35 factors when evaluating orthopaedic residency programs. The percentage of highly rated factors was calculated. Statistical analysis was performed for each factor to assess differences by gender.

Results

Of 1013 applicants who applied to orthopaedic surgery residency in 2017, 815 (80%) applied to our program, and 218 (27%) completed the survey. The most important factors when evaluating a residency program for both genders were (1) perceptions of current residents; (2) interactions with members of the program; (3) program reputation and fellowship placement; (4) geographic location; and (5) impressions after rotation at a program. Female applicants rated the presence of female and minority residents and faculty and program reputation for gender and racial/ethnic diversity higher than male applicants.

Conclusions

When choosing an orthopaedic surgery residency program, women more often reported the presence of female residents and faculty, program reputation for gender diversity, reputation for racial/ethnic diversity, presence of minority residents and faculty, and their personal interactions with members of the program as important factors.
Estudo em bases de patentes sobre a andiroba e suas propriedades anti-inflamatórias
Authors: Carvalho Sabrina Brabo de Araújo , Carvalho Cesar Collyer , Sirqueira Bruna Pereira Carvalho , Silva Rafael de Azevedo , Nylander Bertho Vinícius Rocha , Barros Charles Alberto Villacorta de
Published: September 2019

Objetivo: O presente artigo tem por objetivo conhecer o processo de busca de informações tecnológicas de patentes registradas nos bancos de dados nacional e internacionais sobre a planta medicinal andiroba e suas propriedades anti-inflamatórias. Método: A metodologia usada neste estudo deu-se através de coleta de informações dos documentos nos bancos de dados de patentes no período de maio de 2007 até maio de 2018. Por intermédio da análise de informações tecnológicas existentes sobre registros de patentes, pesquisou-se como palavra-chave “andiroba”. A pesquisa foi realizada nos bancos de dados do Instituto Nacional de Produção Intelectual (INPI), Escritório Europeu Espacenet (EP) e United States Patent and Trademark Office’s (USPTO). Resultados: Quando selecionado o critério “propriedades anti-inflamatórias”, foram encontradas 1 patente no INPI, 3 patentes no EP e 2 patentes no USPTO. Conclusão: Constatou-se que a andiroba apresentou um amplo campo de aplicabilidade no mercado sendo utilizada com objetivos de repelência, estética, ação anti-inflamatória como principal utilização. Assim, os dados coletados nos mostram, na necessidade de novos estudos desta planta medicinal, a possibilidade de gerar mais patentes de invenção no Brasil.