bluuebunny/crossref_metadata_2025 huggingface dataset:
L'oral dans les séances de résolution de problèmes de mathématiques à l'école primaire : des exemples de débats au CE1
Authors: Favrat Jean-François
Published: April 2018

Oral practices in sessions of solving mathematical problems in primary school : examples of discussions of CE1 pupils (7 year old).

Jean-François FAVRAT, IUFM de l'académie de Montpellier, Site de Nimes.

With the object of examining the place, the nature and the role of oral discourse in solving written problems, we wondered if CE1 pupils could discuss their solutions. For this we built a canvas of sessions for the solving of problems during which a collective communication phase on the strategies is foreseen with the aim of bringing out a discussion between the pupils. In this article, we present and analyse the very contrasting observations made during this phase in three CE1 classes where the same problem had been proposed. On the one hand, we noted that moments of debate are possible but do not necessarily appear and we looked for the reasons. On the other hand, we show that, thanks to the debate, the pupils grasp the essential questions for the real practice of mathematics in the class.
Activité littéraire et émergence d'élèves «écrivains » à l'école
Authors: Rebière Maryse , Jaubert Martine
Published: April 2018

Dans le cadre des théories socio-historiques relatives à l'activité humaine, écrire un texte, c'est agir langagièrement dans une communauté dont on s'est approprié les us et coutumes. L'écriture narrative repose ainsi sur la mise en œuvre des pratiques qui caractérisent l'activité des écrivains : apprendre à écrire des récits, c'est s'approprier les contrats de communication spécifiques à la sphère littéraire et ce faisant, s'y inscrire en tant qu'acteur.

C'est pourquoi devenir «romancier » à l'école, c'est, d'une part, construire une représentation des pratiques «lettrées » de l'écrivain et de ses destinataires, et, d'autre part, s'essayer à une nouvelle activité, régulée par un certain nombre de textes et de débats critiques sur ces textes, qui favorisent l'émergence d'une position énonciative nouvelle. On peut donc faire l'hypothèse que le sujet apprenti -romancier se construit au fur et à mesure de l'évolution de sa représentation de l'activité de l'écrivain et de son lectorat ainsi que de l'ajustement de ses pratiques au sein d'un groupe classe qui se constitue en communauté littéraire à la mesure de l'école.

L'étude de la genèse de textes fantastiques, produits par des enfants de CE2, permet de montrer comment, au travers des multiples réécritures qui font l'objet d'évaluations successives de la part des pairs, se négocie et se stabilise ce qui est de l'ordre d'une narration fantastique efficace. Au cours de ces déplacements de genres premiers à genres seconds (pour reprendre la distinction de Bakhtine) se construisent des positions énonciatives nouvelles qui témoignent de la construction du sujet «écrivain ».
Tofacitinib y la necesidad de vigilancia de potenciales efectos adversos en pacientes con artritis reumatoide
Authors: Zegarra Mondragon Sixto
Published: April 2018

Tofacitinib es un inhibidor de JAK-quinasa indicado en el tratamiento de la artritis reumatoide (AR), pudiendo administrarse en monoterapia cuando se ha producido fallo o intolerancia a FAMEs y/o anti-TNF. Por otro lado se debe tener en cuenta un balance entre beneficios y riesgos que podría presentar, especialmente el riesgo de infecciones como aparición de herpes zóster, riesgo de activación de VHB latente y de candidiasis, la relación con neoplasias y linfomas; así como el posible rebrote de actividad articular tras su suspensión una vez alcanzada la remisión; motivos por los que exponemos en este texto dichos aspectos concernientes a la utilización de esta nueva diana terapéutica en AR.
Chemical Abundances of New Member Stars in the Tucana II Dwarf Galaxy∗
Authors: Chiti Anirudh , Frebel Anna , Ji Alexander P. , Jerjen Helmut , Kim Dongwon , Norris John E.
Published: April 2018

We present chemical abundance measurements for seven stars with metallicities ranging from Fe/H] = −3.3 to [Fe/H] = −2.4 in the Tucana II ultra-faint dwarf galaxy (UFD), based on high-resolution spectra obtained with the MIKE spectrograph on the 6.5 m Magellan-Clay Telescope. For three stars, we present detailed chemical abundances for the first time. Of those, two stars are newly discovered members of Tucana II and were selected as probable members from deep narrowband photometry of the Tucana II UFD taken with the SkyMapper telescope. This result demonstrates the potential for photometrically identifying members of dwarf galaxy systems based on chemical composition. One new star was selected from the membership catalog of Walker et al. The other four stars in our sample have been reanalyzed, following additional observations. Overall, six stars have chemical abundances that are characteristic of the UFD stellar population. The seventh star shows chemical abundances that are discrepant from the other Tucana II members and an atypical, higher strontium abundance than what is expected for typical UFD stars. While unlikely, its strontium abundance raises the possibility that it may be a foreground metal-poor halo star with the same systemic velocity as Tucana II. If we were to exclude this star, Tucana II would satisfy the criteria to be a surviving first galaxy. Otherwise, this star implies that Tucana II has likely experienced somewhat extended chemical evolution.
On the Nature of Ultra-faint Dwarf Galaxy Candidates. II. The Case of Cetus II
Authors: Conn Blair C. , Jerjen Helmut , Kim Dongwon , Schirmer Mischa
Published: April 2018

We obtained deep Gemini GMOS-S g, r photometry of the ultra-faint dwarf galaxy candidate Cetus II with the aim of providing stronger constraints on its size, luminosity, and stellar population. Cetus II is an important object in the size–luminosity plane, as it occupies the transition zone between dwarf galaxies and star clusters. All known objects smaller than Cetus II (r

h
 ∼ 20 pc) are reported to be star clusters, while most larger objects are likely dwarf galaxies. We found a prominent excess of main-sequence stars in the color–magnitude diagram of Cetus II, best described by a single stellar population with an age of 11.2 Gyr, metallicity of [Fe/H] = −1.28 dex, an [α/Fe] = 0.0 dex at a heliocentric distance of 26.3 ± 1.2 kpc. As well as being spatially located within the Sagittarius dwarf tidal stream, these properties are well matched to the Sagittarius galaxy’s Population B stars. Interestingly, like our recent findings on the ultra-faint dwarf galaxy candidate Tucana V, the stellar field in the direction of Cetus II shows no evidence of a concentrated overdensity despite tracing the main sequence for over six magnitudes. These results strongly support the picture that Cetus II is not an ultra-faint stellar system in the Milky Way halo, but made up of stars from the Sagittarius tidal stream.
A Survey of CH3CN and HC3N in Protoplanetary Disks
Authors: Bergner Jennifer B. , Guzmán Viviana G. , Öberg Karin I. , Loomis Ryan A. , Pegues Jamila
Published: April 2018

The organic content of protoplanetary disks sets the initial compositions of planets and comets, thereby influencing subsequent chemistry that is possible in nascent planetary systems. We present observations of the complex nitrile-bearing species CH3CN and HC3N toward the disks around the T Tauri stars AS 209, IM Lup, LkCa 15, and V4046 Sgr as well as the Herbig Ae stars MWC 480 and HD 163296. HC3N is detected toward all disks except IM Lup, and CH3CN is detected toward V4046 Sgr, MWC 480, and HD 163296. Rotational temperatures derived for disks with multiple detected lines range from 29 to 73 K, indicating emission from the temperate molecular layer of the disk. V4046 Sgr and MWC 480 radial abundance profiles are constrained using a parametric model; the gas-phase CH3CN and HC3N abundances with respect to HCN are a few to tens of percent in the inner 100 au of the disk, signifying a rich nitrile chemistry at planet- and comet-forming disk radii. We find consistent relative abundances of CH3CN, HC3N, and HCN between our disk sample, protostellar envelopes, and solar system comets; this is suggestive of a robust nitrile chemistry with similar outcomes under a wide range of physical conditions.
Outflowing OH+ in Markarian 231: The Ionization Rate of the Molecular Gas
Authors: González-Alfonso E. , Fischer J. , Bruderer S. , Ashby M. L. N. , Smith H. A. , Veilleux S. , Müller H. S. P. , Stewart K. P. , Sturm E.
Published: April 2018

The oxygen-bearing molecular ions OH+, H2O+, and H3O+ are key species that probe the ionization rate of (partially) molecular gas that is ionized by X-rays and cosmic-rays permeating the interstellar medium. We report Herschel far-infrared and submillimeter spectroscopic observations of OH+ in Mrk 231, showing both ground-state P-Cygni profiles, and excited line profiles with blueshifted absorption wings extending up to ≈1000 km s−1. In addition, OH+ probes an excited component peaking at central velocities, likely arising from the torus probed by the OH centimeter-wave megamaser. Four lines of H2O+ are also detected at systemic velocities, but H3O+ is undetected. Based on our earlier OH studies, we estimate an abundance ratio of

for the outflowing components and ≈20 for the torus, and an OH+ abundance relative to H nuclei of ≳10−7. We also find high OH+/H2O+ and OH+/H3O+ ratios; both are ≳4 in the torus and ≳10–20 in the outflowing gas components. Chemical models indicate that these high OH+ abundances relative to OH, H2O+, and H3O+ are characteristic of gas with a high ionization rate per unit density,

cm3 s−1 and ∼(1–2) × 10−16 cm3 s−1 for the above components, respectively, an ionization rate of ζ ∼ (0.5–2) × 10−12 s−1, and a low molecular fraction,

. X-rays appear to be unable to explain the inferred ionization rate, and thus we suggest that low-energy (10–400 MeV) cosmic-rays are primarily responsible for the ionization, with

M
⊙ yr−1 and

erg s−1; the latter corresponds to ∼1% of the luminosity of the active galactic nucleus and is similar to the energetics of the molecular outflow. We suggest that cosmic-rays accelerated in the forward shock associated with the molecular outflow are responsible for the ionization, as they diffuse through the outflowing molecular phase downstream.
Ecology of the snake Atractus paraguayensis (Dipsadidae) in southern Brazil
Authors: Zanella Noeli , D'Agostini Fernanda
Published: April 2018

Knowledge of snake ecology is important to support conservation strategies.AtractusparaguayensisWerner, 1924 is a dipsadidae with semi fossorial habits distributed throughout southern Brazil. We analyzed the morphology, seasonality and reproductive biology of this species in a subtropical area in southern Brazil by combining material from scientific collections and field data. We found that females have a larger body size than males and that the reproductive cycle of females is seasonal, with vitellogenesis occurring in the warmer months of the year. Males exhibited no differences in testicle volume throughout the year; however, mating likely occurs in the spring when males are more active. Recruitment of newborns occurs in late summer. The number of individuals collected during the hottest months (September through February) was significantly higher than the number of individuals collected during the colder months. Our results, which reveal sexual dimorphism in the species and seasonal breeding restricted to warm months, contribute important information about this species’ biology.
Vertical distribution and structure of copepod (Arthropoda: Copepoda) assemblages in two different seasons down to 1,200 m in the tropical Southwestern Atlantic
Authors: de Oliveira Dias Cristina , de Araujo Adriana Valente , Bonecker Sérgio Luiz Costa
Published: April 2018

The vertical distribution of copepod assemblages, ascertained from the surface down to 1,200 m, was investigated during two sampling periods (rainy and dry seasons), at four depths, in the oligotrophic waters of the southwestern Atlantic Ocean. Total density, diversity, and richness differed among sampling depths. Copepod density decreased with depth in the two sampling periods, with a maximum at 1 m and a slight decrease at 800 m. Higher diversities were observed at 250 m and 1,200 m during the rainy season and at 1 m and 1,200 m during the dry season. The maximum number of species was found at 1,200 m during the rainy season and at 1 m during the dry season. Various copepod assemblages were delimited in the water column in the two sampling periods. The deeper copepod assemblages occupied a wider range of depths. Salinity and temperature influenced the structure of copepod assemblages and reflected the hydrographic characteristics of the water masses in the region. Candaciapachydactyla (Dana, 1849), Scolecithrixdanae (Lubbock, 1856), and Agetuslimbatus (Brady, 1883) were the indicator species found at 1 m. The effects of different environmental factors on the copepod assemblages suggest that these consortia occupy distinct niches in the ocean.
Current Trends in the Use of Shoulder Arthroplasty in the United States
Authors: Palsis John A. , Simpson Kit N. , Matthews J. Hunter , Traven Sophia , Eichinger Josef K. , Friedman Richard J.
Published: April 2018

Reverse total shoulder arthroplasty (rTSA) has become increasingly popular since its introduction to the United States. The purpose of this study was to assess the current trends and use of rTSA, anatomic total shoulder arthroplasty (aTSA), and hemiarthroplasty (HA) from 2011 to 2014. Shoulder arthroplasty data from the National (Nationwide) Inpatient Sample database were analyzed for the years 2011 to 2014 using
International Classification of Diseases, Ninth Revision, Clinical Modification
procedure codes. For each procedure, use and patient and hospital characteristics were identified. Shoulder arthroplasties increased by 24% between 2011 and 2014, to 79,105 procedures. The proportion of arthroplasties that were aTSA did not change substantially (44% for both years;
P
=.0585), while the proportion that were rTSA surpassed aTSA in 2014, increasing from 33% to 46% (
P
<.0001). Use of rTSA topped use of aTSA by 2013 for Medicare patients. The proportion that were HA procedures declined from 23% to 11% (
P
<.0001). The use of rTSA for fracture increased from 26% to 58% (
P
<.0001) of all arthroplasties for this indication, while the use of HA for fracture decreased from 69% to 40% (
P
<.0001). Orthopedists performed rTSA more often than aTSA for Medicare patients by 2013 and the general population by 2014. The use of rTSA for fracture has grown significantly, with rTSA being performed more frequently than HA for this indication. [
Orthopedics
. 2018; 41(3):e416–e423.]
¿Hubo un 68 científico? Su repercusión en action research y mixing methods
Authors: Andrés-Gallego José
Published: April 2018

El autor se plantea si hubo un “68 científico” y se centra en dos aspectos que corresponden a dos propuestas metodológicas definidas en los años cuarenta y cincuenta del siglo XX con las expresiones “action research” y “mixing methods”, aplicadas especialmente en las ciencias sociales. En la primera, el clima creado en torno a los sucesos de 1968 contribuyó a acentuar el sentido participativo que tenía, por definición, la “action research”; es decir: la importancia de que las personas investigadas participen en la elaboración, ejecución y aplicación de esa misma investigación que se hace sobre ellas. Se apelaba ante todo al fondo democrático y antiautoritario que latía en esa propuesta y que se había convertido en parte del clima general dominante en aquellos días. La repercusión del propio 68 en “mixing methods” se centró, por su parte, en el estudio de lo ocurrido (el estudio del 68 por tanto), sobre todo desde el punto de vista sociológico y desde el de la psicología social planteada sobre la base de “mixing methods”. El autor se detiene en la propuesta de Norman Denzin; pero, tanto en el caso del “mixing methods” como en el de la “action research”, se remonta a sus respectivos orígenes inmediatos y, por tanto, a las propuestas que partieron principalmente de Kurt Lewin y la escuela de Chicago.
Historiar la globalización desde el presente. La aportación de los historiadores a los estudios sobre la globalización
Authors: Montero Jiménez José Antonio
Published: April 2018

El presente artículo repasa la contribución de distintos historiadores a los debates sobre el significado, los orígenes y el contenido del término globalización. Este concepto ha sido desvirtuado y cuestionado como consecuencia de su uso sistemático, tanto en ámbitos académicos como entre el público en general. La historiografía se ha ido adaptando a los cambios semánticos sufridos por el término, hasta el punto de que la globalización ha servido para recuperar perspectivas de larga duración, así como enfoques monocausales e incluso deterministas. Sin embargo, algunas de las aportaciones más recientes permiten no solo integrar la globalización en los relatos históricos, sino perfilar su verdadero alcance y significado.
Développer les capabilités des patients pour coproduire un soin sûr et efficace
Authors: Pernet Adeline , Mollo Vanina , Falzon Pierre
Published: April 2018

Cet article cherche à comprendre la dynamique constructive des capabilités des patients en radiothérapie. Dans cette étude, les capabilités des patients renvoient à ce qu’ils sont réellement en mesure de faire en termes de sécurité et d’efficacité des soins. Plus particulièrement, nous allons mettre en évidence les facteurs de conversion qui favorisent ou entravent le développement des capabilités des patients, c’est-à-dire les facteurs qui permettent leur coopération. La méthodologie a combiné des observations de séances de traitement ainsi que des entretiens auprès de professionnels de radiothérapie et de patients. Les principaux résultats soulignent le rôle majeur de la connaissance des risques associés aux soins, de la motivation personnelle, de la relation de confiance, de l’encouragement et du renforcement positif dans le développement des capabilités des patients. De plus, ils permettent de voir comment le contexte et plus précisément les conditions de travail peuvent impacter sur le développement des capabilités des patients et donc sur la coopération soignant-soigné. La discussion met l’accent sur le fait que le développement des capabilités des professionnels est le point de départ au développement des capabilités des patients.
Travail de nuit en 12 heures : un « scénario de travail » élaboré par les infirmiers dans un service de réanimation
Authors: Cheyrouze Marlène , Barthe Béatrice
Published: April 2018

Les 2 x 12 se déploient massivement en milieu hospitalier mais ne sont pas sans risques pour la qualité des soins. Pour à la fois gérer les variations de leur vigilance et atteindre leurs objectifs de soin, les infirmiers emploient dans leur activité des stratégies de régulation. Il s’agit d’étudier la qualité des soins du point de vue des infirmiers et de comprendre en quoi leurs stratégies peuvent contribuer à sa stabilité. L’étude porte sur le travail des infirmiers d’un service de réanimation médicale en poste de nuit de 12 heures. Une observation globale de 18 infirmiers est d’abord menée. Douze infirmiers sont ensuite interrogés en entretiens exploratoires sur leur conception de la qualité des soins et leurs stratégies de régulation. De ces entretiens sont construits trois questionnaires. À quatre moments du poste de nuit, 24 infirmiers évaluent leur vigilance, la qualité des soins et indiquent leurs stratégies de régulation. Ils sont également observés en continu. Après chacune des quatre passations, nous les invitons à commenter leurs réponses en entretien individuel. D’après les résultats, les infirmiers s’estiment de moins en moins vigilants au fil du poste alors que leur perception de la qualité des soins reste très positive. C’est grâce à leur « scénario de travail » élaboré en début de nuit qu’ils la maintiennent à un niveau satisfaisant. Ce scénario leur permet d’anticiper les imprévus, de fiabiliser les soins et d’aménager des temps de repos.
Introduction au dossier “Mettre en scène l’activité : les nouvelles figures de la simulation”
Authors: Ughetto Pascal , Haradji Yvon , Belleghem Laurent Van
Published: April 2018

La simulation de l’activité se présente comme un ensemble varié de méthodes qui prétendent entrer de manière utile dans la conception de nouveaux environnements sociotechniques aussi bien dans les organisations que dans d’autres univers de la vie quotidienne. Issu d’une journée d’étude qui s’est tenue sur le même thème, ce dossier cherche à donner des illustrations variées de ces démarches et tente de prouver la possibilité et l’intérêt de conforter, par ce moyen, le point de vue de l’activité au sein des processus de conception.
County Socioeconomic Deprivation and Preterm Birth Risk Between White and Black Mothers in Georgia, USA
Authors: Tu Wei
Published: April 2018

Past studies have reported the association between living in a socioeconomically deprived neighborhood and elevated preterm births (PtB) risk after adjusting certain individual level confounders. This article examined the association between county-level deprivation and PtB risk of three stratified racial groups, white, black, and the others. The author built two level random intercept logistic regression models using 112,589 single live births retrieved from vital statistics record in Georgia, USA in 2010. Although county level deprivation was found to be insignificant for PtB risk for the entire study population, it had a significant yet modest effect on magnifying the PtB risk of black women (The odds ratio (OR) = 1.063,95% CI = 1.02, 1.12). In addition, the Median Odds Ratio (MOR) (1.229) indicated a weak neighborhood effect on PtB risk and the Interval Odds Ratio (IOR)-80% (0.68-1.49) suggested large unaccounted county-level heterogeneity. Future research will include more confounders at both levels in analysis as well as addressing the uncertain geographic context problem (UGCoP).
Application of Data Fusion for Uncertainty and Sensitivity Analysis of Water Quality in the Shenandoah River
Authors: Mbuh Mbongowo Joseph
Published: April 2018

This article is aimed at demonstrating the feasibility of combining water quality observations with modeling using data fusion techniques for efficient nutrients monitoring in the Shenandoah River (SR). It explores the hypothesis; “Sensitivity and uncertainty from water quality modeling and field observation can be improved through data fusion for a better prediction of water quality.” It models water quality using water quality simulation programs and combines the results with field observation, using a Kalman filter (KF). The results show that the analysis can be improved by using more observations in watersheds where minor variations to the analysis result in large differences in the subsequent forecast. Analyses also show that while data fusion was an invaluable tool to reduce uncertainty, an improvement in the temporal scales would also enhance results and reduce uncertainty. To examine how changes in the field observation affects the final KF analysis, the fusion and lab analysis cross-validation showed some improvement in the results with a very high coefficient of determination.
Community of Inquiry
Authors: Brass Benjamin , de Boer Heike
Published: April 2018

This article establishes a connection between research-based learning and the development of inclusive practices in teacher education with a special focus on pre-service teachers' ways of talking in philosophical dialogues with children. Adopting an interactionist point of view on learning as a co-constructive process and a processual understanding of inclusion and exclusion on the classroom level, the fundamental importance of conversational practices to learning is carved out and then exemplified using transcripts from a teacher education project. Building on this analysis, inclusive conversational practices are identified. Moreover, it is shown how joint reflection and peer feedback in teacher education courses lead to changes in pre-service teachers' conversational practices. These findings lead to reflections on how research-based learning in teacher education can contribute to inclusive education by looking at habitual ways of talking in class.
Democracy as Othering Within Finnish Education
Authors: Simpson Ashley
Published: April 2018

The word democracy is frequently uttered by academics, politicians, and, generally within society. Phrases such as ‘democratic education', ‘democracy education' and ‘(student) participation' are often referred to within national curricula, policy briefings, and, teacher education/training and resources. Little critical attention has been given to the word within the context of Finnish education. In recent years the educational system of Finland has been described as a ‘miracle' and commentators have noted its ‘successes.' This article offers a deeper gaze within Finnish education by looking at the ways democracy discourses are uttered by practitioners. For the purposes of this article the author analyses two in-depth conversation extracts, one was from a youth participation conference in Helsinki in 2015, the other is a conversation from a conference held in February 2016. This article focuses on the uses and functions of discourse to uncover cultural stereotyping and othering in terms of how democracy is discussed and expressed within the context of Finland.
Challenges and Opportunities of Health Information Exchange (HIE) From Health Consumers' Perspective
Authors: Esmaeilzadeh Pouyan
Published: April 2018

The implementation of HIE depends on a number of entities and one of the key participants is health consumers. All potential gains of HIE cannot be achieved without consumers' favorable beliefs and support. However, little is known about the factors affecting consumers to endorse electronic information exchange between healthcare organizations. The primary objective of this article is to identify how and why patients would support HIE used by healthcare providers. The author has conducted an online questionnaire-based survey in the U.S. This study has shown that perceived value of HIE is significantly related to consumers HIE supportive intention. Moreover, perceived value fully mediates the effects of perceived benefit and cost of HIE implementation on consumer tendency to endorse HIE. The findings also provide evidence to highlight that consumers' attitude toward exchange model moderates the relationship between value perception and intention to support HIE. Relying on the results, this study offers several practical and theoretical contributions.
Data Analysis in Radiotherapy Treatments
Authors: Anacleto Ana , Dias Joana
Published: April 2018

Radiotherapy is one of the main cancer treatments available today, together with chemotherapy and surgery. Radiotherapy treatments have to be planned for each patient in an individualized manner. The knowledge acquired from one single treatment can be used to improve the treatment planning and outcome of several other patients. In the last years, attention has been drawn to the added value of using data analysis for radiotherapy treatment planning, prediction of treatment outcomes, survival analysis and quality assurance. In this article, existing literature is reviewed.
Advertising-Cities Face to Smart-Cities
Authors: Jácomo Leticia
Published: April 2018

As much as the content, the strategy for transforming large urban agglomerations into smart cities are not yet clearly defined or even approved among researchers and all the agents involved. Only the general understanding of “smartness” is agreed as a desirable label or beneficial goal for most urban stakeholders. That is why it is essential to study concrete results and exemplary cases that allow the diagnosis of applications and strategies to be truly implemented. In this sense, the actions carried out in the Gran Vía de Madrid, converted into the vanguard of transformation of the capital into a “smart city,” are evaluated in this article as an example of smart urban redevelopment. Urban screens, in their diverse sizes and formats, and surveillance cameras are essential components of this process.
A Systematic Study of Feature Selection Methods for Learning to Rank Algorithms
Authors: Shirzad Mehrnoush Barani , Keyvanpour Mohammad Reza
Published: April 2018

This article describes how feature selection for learning to rank algorithms has become an interesting issue. While noisy and irrelevant features influence performance, and result in an overfitting problem in ranking systems, reducing the number of features by illuminating irrelevant and noisy features is a solution. Several studies have applied feature selection for learning to rank, which promote efficiency and effectiveness of ranking models. As the number of features and consequently the number of irrelevant and noisy features is increasing, systematic a review of Feature selection for learning to rank methods is required. In this article, a framework to examine research on feature selection for learning to rank (FSLR) is proposed. Under this framework, the authors review the most state-of-the-art methods and suggest several criteria to analyze them. FSLR offers a structured classification of current algorithms for future research to: a) properly select strategies from existing algorithms using certain criteria or b) to find ways to develop existing methodologies.
A Novel Delay-Based GFSK Demodulator in 65 nm CMOS for Low Power Biomedical Applications
Authors: Fu Meng , Skafidas Stan , Mareels Iven
Published: April 2018

This article describes how, in recent years, with the development of microelectronics, implantable electronic devices have been playing a significant role in modem medicine. Examples of such electronic implant devices are, for instance, retinal prosthesis and brain implants. It brings great challenges in low power radio frequency (RF) and analog designs. This article presents a low power Gaussian frequency shift keying (GFSK) demodulator designed for Medical Implant Communications Service (MICS) band Receiver. This demodulator utilizes a novel structure that a wide IF range can be handled and presents the smallest Δf/f ratio in any published GFSK demodulators. In theory the demodulation method can be applied to any RF frequency. The demodulator draws 550uA from a 1 V power supply. A maximum data rate of 400 Kbits/s can be achieved within the 300 KHz channel bandwidth defined by MICS. A simulated signal-to-noise ratio (SNR) of 15.2dB at AWGN channel is obtained to achieve 10-3 bit error rate (BER). This demodulator is fabricated on 65-nm CMOS and occupies 0.12mm2 silicon area.
A Study of Forensic Imaging to Evaluate “Unsanitized” Destination Storage Media
Authors: Carlton Gregory H. , Kessler Gary C.
Published: April 2018

Best practices in digital forensics include a procedure to sanitize media on which forensic images will be stored, thus eliminating potential challenges that contamination of the evidence may occur due to data that exist on the media prior to storing forensic images. This article describes a research project to empirically evaluate the extent to which wiping destination storage media affects evidence. The authors specifically address whether the contents of forensic images differ in any way when written to a freshly wiped and formatted medium when compared to the images being written to a similar medium that had been populated with data and not wiped. They performed these experiments on different types of storage devices.
Disconnects of Specialized Mobile Digital Forensics within the Generalized Field of Digital Forensic Science
Authors: Carlton Gregory H. , Kessler Gary C.
Published: April 2018

The study and practice of forensic science comprises many distinct areas that range from behavioral to biological to physical and to digital matters, and in each area forensic science is utilized to obtain evidence that will be admissible within the legal framework. This article focuses on inconsistencies within the accepted methodology of digital forensics when comparing the current best practices of mobile digital devices and traditional computer devices. Here the authors raise the awareness of this disconnect in methodology, and they posit that some specific tasks within the traditional best practices of digital forensic science are artifacts of ritual rather than based on scientific requirements.
Modeling Uncertainty with Interval Valued Fuzzy Numbers
Authors: Dutta Palash
Published: April 2018

This article describes how risk assessment is a significant aid in decision-making process. It is usually performed using models and a ‘model' is a function of some parameters which are usually affected by uncertainty due to lack of data, imprecision, vagueness, and a small sample size.. Fuzzy set is a well-established mathematical tool to handle this type of uncertainty. Normally, triangular fuzzy numbers (TFNs) or trapezoidal fuzzy numbers (TrFNs) are extensively deliberated to embody this type of uncertainty. However, in real world situations, bell-shaped fuzzy numbers may occur to characterize uncertainty. It is pragmatic that type-I fuzzy set may not always dispense single value from [0,1] and on the other hand, assigning a precise value to expert's judgment is excessively restrictive, therefore, the assignment of an interval value is more practical. Thus, interval valued fuzzy set (IVFS) comes into picture. It can be observed that representation of some model parameters of the risk assessment models are triangular interval valued fuzzy numbers (TIVFNs) while representation of some other parameters are bell-shaped IVFNs. In such circumstances, it is most important to devise a technique to combine TIVFNs and bell shaped IVFNs, as they are non-comparable. For this purpose, this article presents a technique to combine both types of incomparable IVFNs within the same framework and finally, a case study is carried out in risk assessment under this setting.
An Efficient Complex Event Processing Algorithm Based on NFA-HTBTS for Massive RFID Event Stream
Authors: Wang Jianhua , Lu Shilei , Lan Yubin , Cheng Lianglun
Published: April 2018

This article describes how quickly picking up some valuable information from massive RFID event stream often faces with the problem of long detection time, high memory consumption and low detection efficiency due to its stream characteristics of volume, velocity, variety, value and veracity. Aim to solving the problems above, an efficient complex event processing method based on NFA-HTBTS (Nondeterministic Finite Automaton-Hash Table B+ Tree Structure) is presented in this article. The achievement of this article lies in that we successfully use the union of NFA and HTBTS to realize the detection of complex event in massive RFID event stream. Specially, in our scheme, after using NFA to match related primitive events from massive RFID event stream, we use hash table and B+ tree structure to successfully realize the detection of complex event from large matched results above, as a result, these problems existed in current methods above can be effectively solved by our scheme. The simulation results show that our proposed scheme outperforms some general methods for massive RFID event stream.
Analysis of Existing Software Cognitive Complexity Measures
Authors: Misra Sanjay , Adewumi Adewole , Damasevicius Robertas , Maskeliunas Rytis
Published: April 2018

In order to maintain the quality of software, it is important to measure it complexity. This provides an insight into the degree of comprehensibility and maintainability of the software. Measurement can be carried out using cognitive measures which are based on cognitive informatics. A number of such measures have been proposed in literature. The goal of this article is to identify the features and advantages of the existing measures. In addition, a comparative analysis is done based on some selected criteria. The results show that there is a similar trend in the output obtained from the different measures when they are applied to different examples. This makes it easy for adopting organisations to readily choose from the options based on the availability of tool support.
Optimized Routing for Efficient Data Dissemination in MANET to Meet the Fast-Changing Technology
Authors: Prakash Deo , Kumar Neeraj , Garg M.L.
Published: April 2018

Mobile Adhoc Network (MANET) is a dynamic network without any centralized control. Due to frequent topological change, routing has been always a challenging task in these networks. This article presents optimized routing for efficient data dissemination in MANETs to meet the fast-changing technology of today's world. A novel metric for such optimized routing in MANET is proposed. The main parameters considered to evaluate this metric are the energy consumed during the communication, link stability, Packet Delivery Ratio (PDR) and traffic. The concept is based on a scenario in which a mobile node (source) sends data packets to another mobile node (destination) through its dynamically connected neighboring nodes. The path which consumes the lowest energy and also shows highest link stability is selected for consideration. In case the paths consume the same amount of energy, the highest stable path is chosen. In this manner, the most optimized path is selected. The authors' routing approach shows more efficiency than earlier in dissemination of data and information over the Mobile Ad-Hoc Networks.
Mobile Sink as Checkpoints for Fault Detection Towards Fault Tolerance in Wireless Sensor Networks
Authors: Parwekar Pritee , Rodda Sireesha , Kaur Parmeet
Published: April 2018

A WSN consists of a large number of limited computation and storage capability wireless sensor nodes, which communicate wirelessly. These sensor nodes typical communicate in short range and collaborate to accomplish the network function. To increase the range of sensing and with the advent of MEMS, mobile sensors and sinks is the technology the world is moving to. This paper presents a network of mobile sensors and a sink. A mobile sink is selected as check-point to have the recoverability of the network. A Fuzzy Rule based system (FRS) is used to construct and select efficient static sensor nodes having adequate resources as Check Point Storage Nodes (CPSNs). The objective of FRS is to increase the probability of recovery of check-pointed data subsequent to a failure, thereby allowing a distributed application to complete its execution successfully. Simulations show FRS's better recovery probabilities in comparison to a random check-pointing arrangement.
Porous Alumina Processing Using the Direct Foaming Technique Based on Slurry Boiling
Authors: Somton Kritkaew , Rodchom Mana , Laoratanakul Pitak , McCuiston Ryan C.
Published: April 2018

The effect of slurry solids content was studied for a novel direct foaming method based on slurry boiling to produce porous alumina ceramics. Slurries with solids contents of 30 to 45 wt. % were produced by conventional processing methods. The physical properties of slurry density and surface tension were measured, as well as thermal properties such as specific heat and latent heat, which were obtained using differential scanning calorimetry (DSC). Samples were fabricated by boiling the slurries on a hot plate until the liquid was completely evaporated. The resultant porous samples were presintered at 1000 °C and were examined to determine the pore size and structure. The measured pore diameter of samples obtained from this experiment were compared with theoretical calculations of departing bubble diameter from a heated surface proposed by Fritz, and Cole & Rohsenow. It was found that the pore size had a relationship with slurry solids content depending on the thermal gradient. The pore size, at a position away from the heated surface, increased as the solids content increased. However, the pore size at the heated surface did not vary significantly with solids content. The results showed that a direct foaming method based on slurry boiling is capable of producing porous alumina and that solids content of the slurry may be utilized to somewhat control pore size and structure.
Synthesis of Zeolite from Water Treatment Sludge and its Application to the Removal of Brilliant Green
Authors: Gomonsirisuk Khemmakorn , Yotyiamkrae Kotchakorn , Prajuabsuk Malee , Lumlong Saisamorn , Kamsri Pharit , Pungpo Pornpan , Thavorniti Parjaree
Published: April 2018

In this work, water treatment sludge from the water treatment plant was used to synthesize zeolite material. In the synthesis, the washed sludge was mixed with sodium hydroxide and then heated at 600ºC for 6 h. After agitation, the aged material was heated in a water bath at 80ºC for different period of aging times. Based on XRD and SEM analyses, Faujasite zeolite was obtained. Then, the feasibility of employing the obtained zeolite as adsorbent for Brilliant Green (BG) removal was investigated. The effect of adsorbent dosage and contact time were examined. Adsorption kinetics and isotherm were also evaluated. The results showed that the obtained zeolite has potential for applying as low-cost adsorbent for the removal of BG from wastewater with higher than 97% adsorption efficiency.
Preparation of Near-Infrared (NIR) Reflective Pigment by Solid State Reaction between Fe2O3 and Al2O3
Authors: Busabok Chumphol , Khongwong Wasana , Somwongsa Phunthinee , Ngernchuklin Piyalak , Saensing Arunrat , Kanchanasutha Sittichai
Published: April 2018

Reflective pigment was prepared by using Fe2O3 and Al2O3 as starting materials. Fe2O3 and Al2O3 powders were mixed at 0.8:2, 1:2 and 1.2:2 mole ratio using ball milling. The mixed powders were dried and calcined at temperature of 1500°C, 1600°C and 1700°C for various soaking time at 2, 8 and 20 h. Phase data were analyzed by x-ray diffractometry. It was found that (Al1-x, Fex)2O3 presented as a new phase in calcined powders at temperature of 1500°C to 1700°C for 2 h. The other new phase such as FeAl2O4 was detected in calcined powders at temperature of 1700°C for 8 and 20 h. From the experimental results indicated that complete reaction was occurred when higher calcination temperature and longer soaking time were used, resulting in spinel structure (FeAl2O4) generated. Then, the synthesized powders were mixed with exterior paint by mass ratio of 0:100, 10:90, 20:80, 30:70 and 40:60, respectively. The mixed paints were sprayed on metal sheets. Then the coated metal sheets were exposed under 200 watts lamb and measured the temperature difference between the exposed side and opposite side. The result showed that at the ratio of 30:70 exhibited the highest temperature difference of 14°C approximately. From the result, we concluded that spinel structure (FeAl2O4) is a candidate for near-infrared (NIR) reflective pigment of exterior paint.
Mechanical Properties and Microstructure of Li2O-SiO2-P2O5-Al2O3-K2O-CaO Glass-Ceramics
Authors: Kamnoy Manlika , Intatha Uraiwan , Munpakdee Anocha , Eitssayeam Sukum , Tunkasiri Tawee
Published: April 2018

In this study, the mechanical properties and microstructure of lithium disilicate glass–ceramics in the Li2O-SiO2-Al2O3-K2O-P2O5-ZrO2-CaO glass system were investigated. The glass-ceramics were prepared from the glass melt by casting into mold on hotplate. After that the glass was heat treated at 650-800 °C for 2 h. The heat treatment temperatures were determined from the differential thermal analysis (DTA). The phase formation and microstructure of the glass–ceramics were characterized by X-ray diffraction (XRD) technique and the scanning electron microscopy (SEM). Moreover, the mechanical properties was investigated by Vickers hardness testing. The results indicated that the samples confirmed the occurrence of Li2SiO3, Li2Si2O5, Li3PO4, and LiAlSi2O6 phases in the prepared glass ceramics. The optimum heat treatment temperature results in the physical properties with a high Vickers hardness values in the range of 5.4-5.8 GPa.
Evaluation of Thermal Shock Resistance for Ceramic Materials by Young’s Modulus
Authors: Arikawa Jun , Shiono Takeshi
Published: April 2018

When a sudden temperature difference is applied to a brittle material such as ceramics, some cracks will occur in the material and it may fracture in some case. The generated cracks as a fracture origin may cause the strength reduction, so the evaluation of thermal shock resistance is very important for ceramic materials. In the conventional evaluation of the thermal shock resistance (thermal shock fracture temperature, ΔTC), the fracture stress is measured after thermal shock test as a function of temperature difference. For this method, however, many specimens are required to estimate fracture stress by bending test and the variation of the stress is large. In the present study, we tried to specify the temperature of crack initiation by measuring Young's modulus and fracture stress before and after a thermal shock test with different temperature difference. Polycrystalline alumina with high purity was used for evaluation of thermal shock resistance. The Young's modulus of all specimens was measured by resonance method. The specimen at the prescribed temperature between 200°C and 600°C, it was quickly put into water to apply thermal shock. The Young's modulus of specimens after the test was measured and the change in Young's modulus before and after thermal shock test was evaluated. Further, the specimen after the evaluation was measured the fracture strength. As a result, it was found that Young's modulus is possible to estimate thermal shock resistance. Further it is also possible to evaluate thermal shock behaviors using only one specimen.
A Novel Radiation Shielding Material for Gamma-Ray: The Development of Lutetium Lithium Borate Glasses
Authors: Glumglomchit Punsak , Rajagukguk Juniastel , Kaewkhao Jakrapong , Kirdsiri Keerati
Published: April 2018

This work, gamma-ray shielding properties of the lutetium lithium borate glasses in the system Lu2O3 - Li2O - B2O3 have been evaluated as a shielding material at 662 keV photon energy. While the experimental mass attenuation coefficients (μm) have been determined by using the narrow beam transmission method, the theoretical data were calculated using WinXCom program. The good agreements between experimental and theoretical values have been obtained. Both experimental and computational mass attenuation coefficients data were used to obtain the effective atomic number (Zeff), and the effective electron density (Nel). Based on the obtained data, the Lu-based glasses have good shielding properties, the improved glasses could be used as gamma-rays shielding material.
Dielectric Properties and Microstructural Studies of Er2O3 Doped Potassium Sodium Niobate Silicate Glass-Ceramics
Authors: Yongsiri Ploypailin , Senanon Wipada , Intawin Pratthana , Pengpat Kamonpan
Published: April 2018

In this work, electrical and structural properties of ferroelectric glasses and glass-ceramics from K0.5Na0.5NbO3-SiO2 doped with 0.5-1.0 mol%Er2O3 system have been investigated. The influent of Er2O3 dopant was also compared with the original glass. The K0.5Na0.5NbO3 (KNN) powder was mixed with SiO2 in composition of 75KNN-25SiO2 and doped with Er2O3. Well-mixed powder was subsequently melted at 1300°C for 15 min in a platinum crucible using an electric furnace. The quenched glasses were then subjected to heat treatment at various temperatures for 4 h. From the study, KNN single phase in transparent glass was successfully prepared via incorporation method. The maximum Ԑr of about 360 at 10 kHz with a low tanδ of 0.07 could be obtained from the glass-ceramic sample of 75KNN–25SiO2 doped 0.5 mol% Er2O3 and heat treated at 600°C. It can be seen that the higher percent of Er2O3 can lower the dielectric loss of KNN glass-ceramics. This interesting value suggesting the opportunity of using them in electronic applications in the future.