bluuebunny/crossref_metadata_2025 huggingface dataset:
Deterministic and probabilistic failure analysis of simple geosynthetic reinforced soil slopes
Authors: Javankhoshdel S. , Bathurst R. J.
Published: July 2016

Reinforced slopes with horizontal layers of geosynthetic reinforcement can have different mechanisms of failure. In this paper two major mechanisms of failure of reinforced slopes are investigated. External mechanisms occur when the critical slip surface passes beyond the reinforced zone. Internal mechanisms are characterised by failure surfaces that intersect all of the reinforcement layers. For a target value of the factor of safety and a specific value of the reinforcement length, there is a minimum value of the reinforcement tensile strength that will generate only external mechanism types. For greater reinforcement strength values, there is no change in the mechanism of failure and the value of the factor of safety. On the other hand, increasing the minimum reinforcement length, while keeping the reinforcement tensile strength equal to or less than the minimum value obtained for an external failure mechanism, will generate an internal mechanism type with the same mean value of factor of safety. In this study, probabilistic slope stability analysis of these two mechanisms is carried out using Monte Carlo simulation of slopes with different purely frictional and cohesive-frictional (c − ϕ) soils and different slope angles. Margins of safety are expressed in terms of a conventional factor of safety and in terms of maximum probability of failure. Cross correlation between soil strength parameters is also considered in this paper. It is shown that considering practical values of cross correlation coefficient reduces the maximum probability of failure for both internal and external failure mechanisms.
A probabilistic approach for estimating the theoretical net drilling rate for offshore bored piles
Authors: Bosco C. , Spagnoli G. , Oreste P.
Published: July 2016

Driven piles, installed by using hammers, are the most common offshore foundation type. However, in certain cases driven piles can incur in a premature refusal (due to plug formations, hard layers, presences of rock and boulders or soil set-up). Drilled piles are therefore used as a back-up solution. However, the technology is not always preferred as time is a key factor for offshore operations and a pile drillability analysis is generally more complex and less reliable than a drivability assessment. This paper extends the results of previous researches, which considered a theoretical drilling rate model based on the estimation of the specific excavation energy, applying a probabilistic approach. To consider the uncertainty of the geotechnical parameters of soil/rock used in drilling pile projects, a statistical method – that is, the Monte-Carlo method, has been applied to two cases of weak rock/cemented soil. It was possible to obtain the theoretical drilling rate values as a probabilistic distribution in order to assess the reliability of the estimation. It is important to understand that the drilling rates are based on a theoretical approach and they have to be considered as such.
Stormwater pond metals and solids removal efficiency determination with the effluent probability method: A novel classification system
Authors: Brink I , Kamish W
Published: July 2016

This technical note contains findings from a larger research project into the design of stormwater detention and retention ponds for removal of metals and solids. The project required a standard system with which case studies obtained from the International Stormwater BMP Database could be compared in terms of efficiency. A novel classification system for use with the Effluent Probability Method, designed for this purpose, was developed and is presented here.
Professional Development and Training for Young Teachers in Russia
Authors: Pinskaya Мarina , Ponomareva Alena , Kosaretsky Sergey
Published: July 2016

Based on TALIS‑2013 results, we analyze professional competencies of young teachers in Russia, their employment patterns, introduction into the profession, professional development, the challenges the meet in teaching, and their satisfaction with the feedback they get from school administrators and colleagues. We show that the corpus of Russian teachers is not homogeneous, as assessments made by teachers of different age differ greatly in all areas. Young teachers have difficulties with professional communication and face barriers in accessing professional development. Meanwhile, they are not ready to solve practical teaching problems and have insufficient knowledge of modern teaching techniques. We come to the conclusion that young teachers need their professional growth opportunities to be extended, primarily through active group-based training. Their chances for successful adaptation to school practice requirements could be increased by establishing an introduction to the profession period to support their basic motivation and prevent the flight of young teachers from school due to low job satisfaction.
Foreword to the Russian edition of Philip W. Jackson’s “Life in Classrooms”
Authors: Froumin Isak
Published: July 2016

In 2016, Voprosy obrazovaniya Library was enriched with another book, the Russian edition of Philip W. Jackson’s classic book on school education, which was first published in 1968 and has become a bestseller for Western teachers and researchers. We introduce the reader to the foreword to this book written by professor Isak Froumin, who was lucky to know the author personally and who is discussing the relevance Jackson’s lessons maintain even nowadays.
"Likes" for Peace: Can Facebook Promote Dialogue in the Israeli-Palestinian Conflict?
Authors: Mor Yifat , Ron Yiftach , Maoz Ifat
Published: July 2016

This study examines the ways in which social media is used to promote intergroup dialogue and reconciliation in the context of the protracted, ethnopolitical conflict between Israeli-Jews and Palestinians. We focus on content analysis of posts and comments on a Facebook page named "Tweeting Arabs", which states that its' main goal is to publicize opinions, thoughts and beliefs of Israeli-Arabs, enabling the moderate voice to be heard and encouraging dialogue between Israeli Jews and Palestinians. The analysis is based on a data set containing posts and comments collected from "Tweeting Arabs" since the page was founded in November 8th 2014 and until December 4th of the same year. This data set contains 85 posts which gained total of 9657 "likes", and 461 "shares", as well as 3565 comments and replies to these posts. Our findings reveal that while posts that presented the narrative of  Palestinian suffering were mostly followed by negative comments from Israeli-Jews, posts that brought up the Palestinian moderate and peace seeking voice elicited higher Jewish-Israeli acceptance and sympathy. The research adds to our understanding of Facebook as a dialogue provoking platform that enables users from different ethnopolitical groups, in divided and conflicted societies to perform peacebuilding actions.
Sleep duration and school performance in Korean adolescents (Duración del sueño y desempeño escolar en adolescentes coreanos)
Authors: Seo Dong-il , So Wi-Young
Published: July 2016

Antecedentes. En este estudio se investigo la relación entre la duración del sueño y el desempeño escolar en adolescentes coreanos. Métodos. En 2012, 63 688 adolescentes participaron en el octavo proyecto de Estudio de Conducta de Riesgo Juvenil Basado en la Red (KYRBWS-VIII, por sus siglas en ingles). La relación entre la duración del sueño y el desempeño escolar se evalúo mediante un análisis de regresión logística multivariada tras ajustar para las variables covariadas, incluyendo índice de masa corporal, edad, nivel educativo de los padres, posición económica, estrés mental, consumo de tabaco, consumo de alcohol, patrones en el desayuno y tres mediciones de actividad física. Resultados. En el caso de los chicos, pero no así en el de las chicas, de cinco a seis horas de sueño por noche se relacionaron con un desempeño académico promedio o mejor que el promedio (R.M.: 1.094, 95% CI [1.011-1.182], p=0.025) en comparación con = cuatro horas/noche. Tanto para los chicos como para las chicas, nueve o mas horas/noche se relacionaron de forma negativa con el desempeño académico (chicos: 0.657 [0.554-0.779; p<0.001]; chicas =9 horas/noche, 0.664 [0.572-0.771], p<0.001) en comparación con =4 horas/noche. Conclusión. Para los chicos, de cinco a seis horas de sueño son necesarias para mantener un desempeño escolar promedio o mejor que el promedio, en tanto que nueve o más horas son perjudiciales para el desempeño escolar de tanto los chicos como las chicas. Otras variables del sueño, como la calidad del sueño y la somnolencia, deben investigarse para obtener una mejor comprensión de estos resultados.
Evaluación de la depresión en pacientes con cáncer terminal y su aplicación en el contexto mexicano: Una revisión
Authors: Landa-Ramírez Edgar , Cárdenas-López Georgina , Andrew Greer Joseph , Sánchez-Román Sofía , Riveros-Rosas Angélica
Published: July 2016

La depresión es uno de los problemas emocionales más frecuentes en pacientes con cáncer terminal. Debido a la evolución de la enfermedad, varios síntomas físicos presentes en los pacientes se pueden yuxtaponer y confundir con los síntomas que permiten identificar de manera taxonómica la depresión, lo cual dificulta la evaluación del problema. El objetivo de este artículo es realizar una revisión de los principales instrumentos utilizados para evaluar la depresión en pacientes con cáncer terminal, junto con sus implicaciones en el contexto mexicano. Con base en la información recabada se puede decir que es más pertinente realizar una evaluación de la depresión enfocada en los aspectos emocionales que en los somáticos. Actualmente existe una gran cantidad de instrumentos para evaluar la depresión que dan mayor énfasis a los aspectos de la anhedonia y las emociones que a los aspectos somáticos de la depresión. En México existe un enorme rezago en el desarrollo de instrumentos que permitan identificar estos síntomas. Se concluye señalando instrumentos alternativos para evaluar la depresión en pacientes con cáncer terminal, estos instrumentos podrían ser evaluados y considerados en un futuro en el contexto de la medicina paliativa.
Adversidad social y trastornos psiquiátricos: Estudio comparativo entre estudiantes de secundarias públicas y privadas
Authors: De la Peña Olvera Francisco R. , Gómez Castro Cecilia , Heinze Martin Gerhard , Palacios-Cruz Lino
Published: July 2016

Los trastornos psiquiátricos en la adolescencia se vinculan con algunas adversidades sociales como la disfunción familiar y el abuso. En la Ciudad de México, hasta el 68% de los adolescentes ha sufrido al menos una adversidad crónica y los problemas de salud mental, como la depresión y el trastorno por déficit de atención con hiperactividad, son frecuentes y ocasionan problemas académicos. Las diferencias sociales y económicas de los alumnos de secundarias públicas y privadas son bien conocidas, sin embargo no se ha establecido cuáles son las diferencias entre la adversidad social y los trastornos psiquiátricos entre estas poblaciones. El objetivo de esta investigación fue diagnosticar, en un procedimiento clínico de dos pasos, y comparar estas características en los adolescentes de secundarias del sur de la Ciudad de México. Método. Se realizó un acuerdo por conveniencia con siete secundarias del sur de la Ciudad de México, cuatro públicas y tres privadas. Previo consentimiento de los padres y asentimiento de los adolescentes, se aplicó un tamizaje clínico que evaluó sintomatología internalizada y externalizada en 1 474 alumnos. El tamizaje positivo a probable psicopatología se encontró en 419 alumnos, de los cuales 319 aceptaron la entrevista clínica y se presentaron a la misma 117. Resultados. De los 117 adolescentes entrevistados, 83.8% fueron casos, más frecuentes en los alumnos de escuelas públicas que en las privadas: 64 (91%) vs. 34 (71%), (?2=7.85; P=0.005). La edad promedio fue de 13.39 años (DE=0.98). La disfunción familiar se encontró en 57 (48.71%) de los 117 adolescentes. El funcionamiento general fue evaluado mediante el GAF, la puntuación media de todos los alumnos fue de 65.48 (DE=11.68). El trastorno depresivo mayor y el trastorno por déficit de atención con hiperactividad fueron los diagnósticos más frecuentes: 48.7% y 59.8%, respectivamente. El abuso psicológico y físico, la disfunción familiar y el trastorno depresivo mayor se presentaron significativamente más en los alumnos de las escuelas públicas. Conclusiones. La adversidad social y la depresión se presentan y se asocian más frecuentemente en alumnos de secundarias públicas que en las privadas. Esto representa un reto para los servicios educativos y de salud mental para el reconocimiento temprano y la atención oportuna, ya que existe una vinculación entre el bienestar social y la salud mental.
The transformation of scientific style in the changing communication environment. Features of the modern scientific article
Authors: Ivanitskaya E.V.
Published: July 2016

Understanding the specifics of scientific style is required for successful communication with the world scientific community. The paper studies the development of scientific style in Russia, its main tasks and genres, as well as the structure and specifics of modern scientific articles as the effective means of international communication. Being the main genre of scientific style, scientific article is a vivid illustration of its development and constant transformation. Today, not only the relevance and novelty of the research are required for recognition and interaction with the international scientific community, but also the observance of a number of formal principles of the scientific article writing.
Surgical techniques for the treatment of tongue tie in children: a comparative study
Authors: Gujrathi Atishkumar , Ambulgekar Vijayalaxmi , Handal Ashwini
Published: July 2016

Background: Ankyloglossia is another name for tongue tie which in mild form is characterized by mucous membrane bands to complete ankyloglossia whereby the tongue is tethered to the floor of the mouth. It can affect feeding, speech, and oral hygiene as well as have mechanical/social effects. Ankyloglossia can also prevent the tongue from contacting the anterior palate.

Methods: The study aimed to find out best possible surgical modality of frenectomy by comparing scalpel, electro-cautery and CO2 laser in the treatment of tongue tie. This is a prospective randomized clinical trial conducted in the department of ENT, Dr. Shankarrao Chavan Government Medical College, Nanded, Maharashtra. All patients were categorized in to three groups randomly as group A, group B and group C. Each group contains 18 patients and among group A, B and C, frenectomy was done by conventional scalpel technique, by bipolar cautery and CO2 laser respectively. Then patients were assessed on post op day 1 for symptomatology and inflammatory signs, on post op day 7 for wound healing and any complications and also after 1 month post-op for scar and contracture of wound.  

Results: In our study, about 61% of population is of male child and female child were remaining 39% (ratio 1.6:1) which is matching with the previous studies. Amongst all patients most common age group is between 1-4 years of age group. Most of the patients were in Kotlow’s class III having severe ankyloglossia (3‑7 mm) followed by class I having Mild ankyloglossia (12‑16 mm).

Conclusions: Laser and electro-cautery treatment used for frenectomy operations provides better patient perception in terms of postoperative pain and function than that obtained by the scalpel technique.
Development of word lists in Telugu for assessing speech recognition threshold: alternative forms to existing word lists
Authors: Rathna Kumar S. B. , Sudharshan Reddy. B Madhu , Kranthi Sale
Published: July 2016

Background: The present study aimed to develop word lists in Telugu for assessing speech recognition threshold which might serve as equivalent and alternative forms to the existing word lists.

Methods: A total of two word lists were developed using compound words with each list consisting of 25 words. Equivalence analysis and performance-intensity function testing was carried out using two word lists on a total of 75 native speakers of Telugu who were equally divided into three groups.  

Results: The results revealed that there was no statistically significant difference (p>0.05) in the speech recognition performance between three groups for each word list, and between two word lists for each group. Hence, the two word lists developed were found to be equally difficult for all the groups and can be used interchangeably. The performance-intensity (PI) function curve showed semi-linear function, and the subjects reached the beginning of the plateau at 3 dBSL where they reached more than 90% speech recognition score for two word lists, and reached 100% speech recognition score at 6 dBSL. The 50% speech recognition score which corresponds to SRT was obtained at less than 1.5 dBSL for two word lists suggesting good agreement between PTA and SRT.

Conclusions: The findings of the study are similar to the findings of existing word lists in Telugu. Thus the developed word lists in the present study can be considered equivalent and alternative forms to existing word lists in Telugu.
"When you follow your heart, you provide that path for others": Indigenous Models of Youth Leadership in HIV Prevention
Authors: Monchalin Renee , Flicker Sarah , Wilson Ciann , Prentice Tracey , Oliver Vanessa , Jackson Randy , Larkin June , Mitchell Claudia , Restoule Jean-Paul , Network Native Youth Sexual Health
Published: July 2016

Cultivating and supporting Indigenous peer youth leaders should be an important part of Canada’s response to HIV. This paper examines how a group of Indigenous youth leaders took up the notion of leadership in the context of HIV prevention. Taking Action II was a community-based participatory action research project. Eighteen Indigenous youth leaders from across Canada were invited to share narratives about their passion for HIV prevention through digital storytelling. One-on-one semi-structured interviews were conducted with participants after they developed their digital stories, and then again several months later. A thematic analysis of the interviews was conducted to identify major themes. Youth identified qualities of an Indigenous youth leader as being confident, trustworthy, willing to listen, humble, patient, dedicated, resilient, and healthy. A number of key examples and challenges of youth leadership were also discussed. In contrast to individualized mainstream ideals, Indigenous youth in our study viewed leadership as deeply connected to relationships with family, community, history, legacies, and communal health.
EMERGÊNCIA DE RELAÇÕES ORDINAIS SOB CONTROLE CONTEXTUAL EM SURDOS
Authors: Souza Ruth Daisy Capistrano de , Magalhães Priscila Giselli Silva , Assis Grauben , Goulart Paulo Roney Kilpp
Published: July 2016

O presente estudo visou a ampliar a investigação de procedimentos computadorizados de ensino com controle contextual sobre relações ordinais. Participaram cinco crianças surdas com história experimental em discriminações simples e condicional. A tela do computador era dividida em “área de escolha” (parte inferior), na qual os estímulos eram apresentados de forma aleatória, e “área de construção” (parte superior), para a qual os estímulos se deslocavam. Dois estímulos eram apresentados simultaneamente, e os participantes deviam selecioná-los sequencialmente (p. ex., A1?A2, na presença do círculo e da cor “verde”; ou A2?A1, na presença do triângulo e da cor “vermelha”). O delineamento experimental envolveu as seguintes fases: pré-testes, treinos, sondas, testes de transitividade, revisões de linha de base e testes de substitutibilidade. O critério de acerto era de três tentativas corretas consecutivas. Todos os participantes alcançaram o critério de acerto e responderam aos testes de transitividade e conectividade. Os resultados mostram evidências de controle contextual sobre as relações emergentes, sugerindo que o estabelecimento de controle discriminativo simples e condicional foi fundamental para a emergência de classes ordinais sob controle contextual. Palavras-chave: controle de estímulos, estímulo contextual, relações ordinais, crianças surdas.
Composição e distribuição de crustáceos decápodes associados í­Â pesca do camarão-sete-barbas Xiphopenaeus kroyeri (Heller, 1862) no litoral norte do Estado de São Paulo
Authors: MANTELATTO Fernando L. , BERNARDO Camila H. , SILVA Thiago E. , BERNARDES Verônica P. , COBO Valter J. , FRANSOZO Adilson
Published: July 2016

O objetivo deste estudo foi identificar, espacial e temporalmente, a composição e a diversidade de crustáceos decápodes capturados na pesca do camarão Xyphopenaeus kroyeri na enseada de Ubatuba. As coletas foram realizadas mensalmente, com barco de pesca camaroeiro, de setembro de 1995 a agosto de 1996 em oito transectos permanentes. No total, foram coletados 233.094 indiví­­duos pertencentes a 85 espécies. As maiores riquezas foram para os grupos Brachyura (49 espécies) e Anomura (16 espécies). Nos transectos IV e V foram encontrados os maiores valores de diversidade e o menor número de indiví­­duos do camarão X. kroyeri. Com relação í­Â  similaridade, os transectos IV e V apresentam baixa similaridade em relação aos demais transectos devido í­Â s suas caracterí­­sticas, como localização na enseada e tipo de substrato. Estudos sobre a diversidade de fauna acompanhante de camarões de interesse comercial são imperativos para planos de manejo e conservação dos recursos naturais renováveis.
Biologia populacional e dieta de Callinectes sapidus (Decapoda, Portunidae) no Saco da Fazenda, Itajaí­­, Santa Catarina, Brasil
Authors: PORT Dagoberto , FISCH Fabiane , BRANCO Joaquim Olinto
Published: July 2016

O gênero Callinectes tem presença constante nas atividades extrativistas praticadas por comunidades litorí­¢neas. O objetivo do trabalho é fornecer informações básicas sobre a biologia populacional e a dieta do siri-azul, C. sapidus, no Saco da Fazenda (Itajaí­­/SC). O tamanho da primeira maturação foi estimado em 10,8 cm (fêmeas) e 8,8 cm (machos) de largura total de carapaça. A CPUE apresentou os valores mais baixos na primavera e os mais elevados no outono. Para o perí­­odo 2002-2003, a diferença entre o número de machos e o de fêmeas não foi significativa, com uma razão de 0,84. Entretanto, para os perí­­odos 2003-2004 (razão=0,75) e 2004-2005 (razão=1,37), a diferença entre o número de machos e o de fêmeas foi significativa. As maiores taxas mensais de biomassa foram registradas nos meses de abril, maio, junho e julho. Para a análise da dieta foram analisados 254 indiví­­duos (120 machos e 134 fêmeas). A análise do teste X2 aplicada í­Â  proporção dos sexos não demonstrou diferença significativa. A maioria dos machos (80%) e das fêmeas (78,36%) apresentava o estômago com conteúdo. Foi possí­­vel identificar 12 itens alimentares na dieta, sendo que os de maior importí­¢ncia foram os de origem animal. Os itens de origem vegetal representam um papel secundário na dieta da espécie.
Efeito da proporção sexual sobre o desempenho reprodutivo do camarão-rosa Farfantepenaeus brasiliensis (Decapoda: Penaeoidea)
Authors: FLOR Helaine dos Reis , OSHIRO Lidia Miyako Yoshii , COSTA Tiago Viana da , FUGIMURA Michelle Midori Sena , RODRIGES Felipe Nolasco Gomes , MATTOS Luciana Antunes de
Published: July 2016

Farfantepenaeus brasiliensis é uma espécie de camarão nativa da costa brasileira, sendo um dos recursos pesqueiros mais explorados. Com o intuito de colaborar no desenvolvimento de técnicas para promover o cultivo da espécie, o objetivo deste trabalho foi avaliar seu desempenho reprodutivo em cativeiro, submetida a diferentes proporções sexuais. Os reprodutores foram capturados na Baí­­a de Sepetiba/Brasil e mantidos em tanques de maturação. Os animais, num total de 108, foram distribuí­­dos aleatoriamente em 18 tanques nas proporções 1:1 e 1:2 (M:F). As fêmeas foram abladas unilateralmente e identificadas mediante marcações em seus urópodos. A avaliação do desempenho reprodutivo foi realizada através do número de desovas, fecundidade, fertilidade e taxa de eclosão, sendo determinados o tamanho (32,00 mm de CC) e o peso (24,00 g PV) mí­­nimos ideais para a reprodução em fêmeas. As melhores taxas de fertilidade e eclosão indicam que a proporção sexual de 1:2 é a mais adequada para esta espécie.
Crescimento relativo e tamanho na maturidade sexual do lagostim Metanephrops rubellus (Moreira, 1903) desembarcado no litoral do Estado de São Paulo, Brasil
Authors: SEVERINO-RODRIGUES Evandro , FURQUIM Ligia Gomes , GRAÇA-LOPES Roberto da , ALVES Pedro Mestre Ferreira
Published: July 2016

A estatí­­stica pesqueira paulista mostra considerável oscilação anual na quantidade de lagostim desembarcado, a princí­­pio devido a altos e baixos no interesse do setor pesqueiro. No entanto, fatores biológicos também podem estar influenciando, já que pouco se conhece da biologia de M. rubellus, pois as principais referências disponí­­veis sobre nefropí­­deos referem-se ao lagostim norueguês (Nephrops norvegicus), espécie europeia similar morfológica e comportamentalmente. As relações morfométricas encontradas caracterizam o crescimento relativo de M. rubellus como alométrico positivo, exceto para Ct x Cc e Pt x Pa, que mostraram isometria. O comprimento de iní­­cio da fase de maturidade (L50) e a distribuição de comprimentos dos exemplares capturados indicam que a pesca incidiu preferencialmente sobre indiví­­duos aptos í­Â  reprodução. Devido a isto e í­Â  similitude biológica e comportamental entre N. norvegicus e M. rubellus não são indicados o defeso ou o tamanho mí­­nimo de captura como instrumentos de gestão da pescaria, propondo-se a realização de pesquisas para definir a área de distribuição e densidade da população, visando estabelecer áreas de exclusão de pesca que funcionem como reservatórios para a reposição dos estoques. É essencial ainda monitorar o comportamento dos parí­¢metros de diní­¢mica populacional, visando ao controle do esforço de pesca.
Biologia populacional de Callinectes ornatus associada í­Â pesca do camarão-sete-barbas, rio São Francisco (Alagoas e Sergipe, Brasil)
Authors: SANTOS Maria do Carmo Ferrão , PORT Dagoberto , FISCH Fabiane , BARBIERI Edison , BRANCO Joaquim Olinto
Published: July 2016

A carcinofauna que acompanha a pesca artesanal do camarão Xiphopenaeus kroyeri (Heller, 1862) é bastante diversificada, com destaque í­Â  captura do siri Callinectes ornatus (Ordway, 1863). Neste estudo, o material biológico foi coletado mensalmente durante um ano (janeiro a dezembro/2011), proveniente de embarcação motorizada da frota camaroeira de arrasto. C. ornatus totalizou 891 indiví­­duos, dos quais 57,9% eram machos. A média de largura do cefalotórax (LC) foi maior nos machos (29,2 mm) do que nas fêmeas (24,8 mm); para os machos, as capturas concentraram-se em indiví­­duos com LC entre 8 e 44 mm, e fêmeas entre 10 a 42 mm; o recrutamento, levando-se em consideração os menores tamanhos (LC), foi registrado em um perí­­odo contí­­nuo de seis meses para os machos (dezembro a maio), similar aos sete meses constatados para as fêmeas (novembro a maio). A relação peso-tamanho dos espécimes foi alométrica positiva para os machos (b=3,17) e fêmeas (b=3,04). Os dados obtidos fornecem informação básica, indispensável como subsí­­dios ao ordenamento e manejo pesqueiro do siri, particularmente na região de abrangência da pluma estuarina do Rio São Francisco (Alagoas e Sergipe, Brasil).
Caracterização da pesca e dos pescadores artesanais de camarões Penaeidae em salina no municí­­pio de Macau - Rio Grande do Norte
Authors: SANTOS Maria do Carmo Ferrão , SANTOS Caio Floriano dos , BRANCO Joaquim Olinto , BARBIERI Edison
Published: July 2016

A pescaria de camarões peneí­­deos em bacias de captação (evaporadores) de água que abastecem as salinas do litoral setentrional do estado do Rio Grande do Norte é bastante comum. Foram aplicados 40 questionários semi-estruturados, de março a outubro de 2011, entre os pescadores com atividade na SALINOR, em Macau. Temas relacionados a extração de sal e atividade petrolí­­fera nos manguezais e no seu entorno, as informações foram obtidas por levantamento bibliográfico. A pesca artesanal de peneí­­deos é noturna, com mais de 100 pescadores que exercem sua atividade em dupla e utilizam a tarrafa e luz artificial. A produção média anual de camarão, é em torno de 4kg de camarão/noite/tarrafa, porém, durante a safra, geralmente no último quadrimestre do ano, a produção média é de aproximadamente 20kg de camarão/noite/tarrafa. A espécie com maior participação é Farfantepenaeus brasiliensis (61%), seguida de Farfantepenaeus subtilis (24%). Todos os pescadores entrevistados afirmam não estimular seus filhos e netos a exercer a atividade de pesca. É recomendável a continuação desta modalidade de pesca, devido a sua importí­¢ncia  socioeconômica, além, da salina funcionar como uma armadilha, não oferecendo aos peneí­­deos, seu retorno para o mar e, consequentemente, a conclusão do seu ciclo biológico.
Triangular Prism and Slit Electrode Pair for ECF Jetting Fabricated by Thick Micromold and Electroforming as Micro Hydraulic Pressure Source for Soft Microrobots
Authors: Kim Joon-Wan ,   Precision and Intelligence Laboratory, Tokyo Institute of Technology, Nguyen Thanh V. X. , Edamura Kazuya , Yokota Shinichi ,   ,,   Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Yokohama, Japan,   New Technology Management Co., Ltd., Tokyo, Japan
Published: July 2016

In this paper, we propose a triangular prism and slit electrode pair (TPSE) and its micromechanical systems (MEMS) fabrication process for a novel micropump using electro-conjugate fluid (ECF), which is based on a thick photoresist (KMPR) micromold (≥ 500 μm) and nickel electroforming. ECF is a kind of functional and dielectric fluid. The strong and active jet flow of an ECF is generated between two electrodes surrounded by the ECF when a high direct-current voltage is applied to the electrode pair. The micropumps generated by the ECF jetting can be used as micro hydraulic pressure sources for soft microrobots. By substituting these ECF micropumps for bulky air compressors or hydraulic pumps utilized in soft robots, we can realize advanced soft microrobots in which the driving sources are embedded. An MEMS-based TPSE for an ECF micropump was successfully fabricated by using the proposed MEMS fabrication process. The maximum output pressure without a flow and the flow rate without a load were 24.6 kPa and 27.5 mm3/s, respectively, at an applied voltage of 2 kV. The experimental results show that the MEMS-fabricated TPSE is a good candidate for electrode-type ECF micropumps utilized in various applications of soft microrobots whose pressure sources are embedded inside.
Modeling and Force Control of Thin Soft McKibben Actuator
Authors: Faudzi Ahmad Athif Mohd ,   Center for Artificial Intelligence and Robotics (CAIRO), Universiti Teknologi Malaysia, Lazim Noor Hanis Izzuddin Mat , Suzumori Koichi ,   ,,   Universiti Sains Islam Malaysia, Negeri Sembilan, Malaysia,   Department of Mechanical and Aerospace Engineering, Tokyo Institute of Technology, Tokyo, Japan
Published: July 2016

This paper presents the modeling of a thin soft McKibben actuator using the system identification (SI) method and its force control. Procedures from the system identification method are used to create a mathematical model (transfer function) from the test data. The autoregressive with exogenous input (ARX) model was chosen as the model structure of the system. Next, a PSO-PID controller was proposed for the force control of the actuator. The simulation data were verified against the test data for the force control using PSO-PID and conventional PID. Results showed that the developed model represents the actual system by giving the same characteristics in the force control analysis in step, multi-step, and sinusoidal input.
Omnidirectional Soft Robot Platform with Flexible Actuators for Medical Assistive Device
Authors: Ribuan Mohamed Najib ,   Graduate School of Natural Science and Technology, Okayama University, Wakimoto Shuichi , Suzumori Koichi , Kanda Takefumi ,   ,,   Department of Mechanical and Aerospace Engineering, Graduate School of Science and Engineering, Tokyo Institute of Technology
Published: July 2016

This manuscript explains the employment of flexible actuators to act as a soft robot and transporting agent to assist medical X-ray examinations. Although soft robots from silicone material can be transparence and a human compliance used as medical assistive devices, soft robots have some problems: they tend to be sluggish, have long and imprecise gait trajectories, and need their control parameters to be adjusted for motion diversion. A soft robot with omnidirectional locomotion has been created, one that has a combination of pneumatic rubber legs that form a soft robot platform and an associated hardware setup. Tests have confirmed its omnidirectional locomotion ability; it has a maximum speed of 6.90 mm/s in forward locomotion and a maximum payload of 70 g. These features indicate that the robot can be used as a medical assistive device for fluoroscopy examinations.
Development of a Rubber Soft Actuator Driven with Gas/Liquid Phase Change
Authors: Matsuoka Hiroki ,   Okayama University, Kanda Takefumi , Wakimoto Shuichi , Suzumori Koichi , Lambert Pierre ,   ,,   Tokyo Institute of Technology, Tokyo, Japan,   Université libre de Bruxelles, Bruxelles, Belgium
Published: July 2016

Soft rubber actuators are very useful in applications involving humans, such as in medicine and reflexology. Additionally, they are useful in industrial devices because of their softness. However, many soft rubber actuators are driven by pneumatic power, and the power source is usually bulky. This makes the application of soft rubber actuators difficult. In this study, we propose a novel small power source for soft rubber actuators, which uses the gas/liquid phase change phenomenon of the actuator working fluid. When fluids change their phase between liquid and vapor, a large volume change occurs. We assume that this volume change is sufficient to drive a single soft rubber actuator. We fabricated a prototype of an actuator comprised entirely of silicone rubber via a molding process. Using the first prototype, we confirmed that the actuator can be driven by the gas/liquid phase change of the actuator fluid. Then, we fabricated a second prototype that includes a cartridge heater inside its body. We applied an electronics coolant fluid to this actuator. From the results of several experiments, we confirmed that the actuator produced a maximum output force of 405 mN. When the actuator was driven by the gas/liquid phase change, its trajectory was almost the same as that when driven by air pressure. Hence, the proposed pressure source maintained the characteristics and advantages of the soft rubber actuator. We believe that a pressure source using the gas/liquid phase change phenomenon of a working fluid will mitigate the problems of the driving system of soft rubber actuators.
Specialized Mixing Spool to Increase The Efficiency of Chemical Mixing with Crude Oil
Authors: Rodulfo Hernandez J. L. , Audah N. T. , Al-Ajmi S. M.
Published: July 2016

Chemical consumption and wash water usage has risen in the past few years due to oil production having increasing water cut and emulsions. Saudi Aramco has installed and tested a new chemical injection spool that enhances the mixture of the injected chemicals and the incoming multiphase flow. The test consisted of two chemical injection spools: 24 in. and 30 in. units.

The injection mixing spool has no moving parts and is installed upstream of the separator at the gas-oil separation plant (GOSP). The mixer incorporates specialized injection ports that channel the chemicals into grooves that ring the pipe and provide 360 degree injection. In addition, the internal geometry of the mixer generates turbulent eddies that enhance mixing. This static mixing spool has three injection ports: demulsifier, corrosion inhibitor, and scale inhibitor.

The first system (24 in.) was installed and commissioned during the plant's maintenance in April 2013. The trial test of the chemical injection mixing spool spanned the summer months, which typically see a lower chemical consumption, as well as the winter months. Since being set on stream, the system has achieved a 48% reduction of demulsifier injection, which is a costly chemical. In addition, the wash water consumption was reduced by 31%, which supports the reduction of overall ground water consumption. These improvements were achieved while maintaining process integrity and desalting train efficiency.

The second system (30 in.) was installed and commissioned similarly in May 2014. This unit achieved a 17% reduction in demulsifier dosage. Also, the reduction in wash water consumption was estimated at 12%.

This paper describes the background to conventional chemical injection and mixing, specialized mixing spool design and working principles, implementation, and impact of the installation of the chemical injection mixing spool.
New Multiphase Flow Measurement Technologies for Wet Gas Application: Qualification and Field-Testing in Saudi Aramco Fields
Authors: Faraj Ali , Benlizidia Imed , Ruwaili Essa , Anazi Mohammad , Dabbous Mohammad
Published: July 2016

The purpose of this paper is to present and discuss the results of a qualification test of four Multiphase Flow Meter (MPFM) technologies in wet gas environment against a reliable and fully auditable test separator used with redundant measuring devices as a reference measurement. It will also clearly set procedures, and evaluation criteria used to qualify MPFM in Saudi Aramco gas condensate/wet gas fields in Saudi Arabia.

This trial test was designed to ensure that clear conclusions are reached and that a purely objective evaluation of the results can be performed. The implementation of this new procedure has improved the confidence level of the reference measurement and eliminated any doubts on the performance of the test separator. In this challenging environment of wet gas, this has enabled a clear mapping of each MPFM technology performances and limitations versus operating and fluid conditions.

It is the first time in Saudi Aramco to conduct a field trial test using a test separator where secondary measurements are used to enhance the reliability of the reference measurements, which resulted in a very accurate performance mapping of the four MPFM technologies. This trial test has set a standard procedure that can be used to qualify any future MPFM technologies in Saudi Aramco fields.
Application of DCS Design Modification to Eliminate Structure Impact on Offshore Platforms and Avoid Collision Risk in GOS. Case Study: First Time 37 Ft 30"X15" DCS Window
Authors: Eissa Amr , Moris Maged , Mohamed Hesham , Elmaati Lotfi Abou , Hussein Ahmed
Published: July 2016

Gulf of Suez "GOS" in Egypt is a mature oil field where platforms are crowded with wells. Drilling new wells from empty slots or as a slot recovery is a challenging due to collision risk with neighbor wellbores. Deflecting Conductor Sleeve "DCS" is a known tool typically used to control the placement of the conductor away of the old conductor stump. The DCS window length ranges from 70 to 90 ft and usually requires platform modification (cutting of slot guides & members) to accommodate the big diameter of the DCS and conductor pipe protruding from the DCS window.

Modifying the DCS design by reducing the width of the DCS's deflecting surface gives the chance to decrease the window length greatly while keeping the same conductor angle at the seabed, acceptable range of dogleg severity and bending stresses. This approach has been used successfully in one of Gupco wells and resulted in mitigating serious collision risk and eliminating the need for platform modification or slot extension. This paper presents conventional techniques used in GOS to avoid collisions in the conductor phase in addition to a new approach of using Conductor Deflecting Sleeve "DCS" design modification and a case study on the first time usage of 37 ft 30″×15″ DCS window.
Wellbore Temperature Prediction and Control Through State Space Model
Authors: Minghui Wei , Gensheng Li
Published: July 2016

The present trend of drilling deeper wells has increased the importance of estimating the wellbore temperature distribution and its variation with time. The need arises because it has a number of applications, such as: Cementing program design, drilling fluid rheology and design, drill tools planning, estimating mud properties and so on. The current wellbore temperature calculation method is through solving partial differential equation that obtaining the well temperature distribution. This method could obtain the well temperature distribution in different time and position, but the inherent characteristics could not be revealed. We plan to establish the well temperature state space model, and analyze the dynamic characteristics of well temperature according to this method and control theory.

This work presents a study of the thermal behavior of drilling fluid during circulation and shut-in stages. A state space model is developed to calculate wellbore temperature distribution instead of solving partial differential equation. This model is based on wellbore heat transfer mechanism model and control theory. We analyze the dynamic characteristics of well temperature according to the state space model and control theory. Then we analyze how to adjust and control the bottom-hole temperature through operating surface parameters. The performance of the method is illustrated via the simulation of Holmes test well data.

Wellbore temperature distribution profile and its variation with time are obtained according to the state space model. The calculation results shows that the maximum temperature is not appeared in the bottom-hole but appeared in some distance from the bottom-hole. The wellbore temperature will reach steady state in a few of circulation hours, the time to steady state is determined by fluid density, flow rate, specific heat. The bottom-hole temperature decreases as the flow rate or fluid density improving. Besides, we analyze the stability of wellbore heat transfer system according to Lyapunov theorem. The wellbore heat transfer system is steady system without large disturbance. This study can provide theoretical basis for automatic control of wellbore temperature in the future.
Novel Slim-Matrix PDC Construction Boosts Drilling Efficiency: A Field Study
Authors: El Oufy Mamdouh , Ragheb Ahmed , Sherif Mohamed , Hanafy Omar , El Sherif Omar , Aguib Karim
Published: July 2016

One of the perceived drawbacks of matrix polycrystalline diamond compact (PDC) bits compared with steel PDC bits is their restricted open-face volume and smaller blade standoff, which is primarily caused by the matrix PDC bits' brittle nature. Increased blade standoff gives steel PDC bits a more hydraulically efficient body type, which directly affects ROP. In many drilling applications, operators switch to steel PDC to take advantage of their hydraulic efficiency, and recent developments in hardfacing material has expanded the range of applications of such bits. However, there are applications that are still dominated by matrix PDC bits, and a need arose for matrix material that can allow the molding of slim, hydraulically efficient matrix bodies.

A new matrix material with enhanced toughness allows for the design of a slim-body matrix construction. This innovative concept has been validated for structural integrity, which was the main perceived risk. The technology was rolled out for 8½-in and 12¼-in hole sections and deployed in a field test campaign in all of Egypt's different rock columns.

The effect and value of faster ROP increases with application complexity and depth and is directly proportional to rig spread rate. Hence, realizing the application limits of slim-body matrix technology was the main intent of this study. Success was measured by observing the effect of hydraulic efficiency across different fields in terms of ROP and cost savings. Further, to isolate the effect of slim-body construction, several tests were conducted between standard matrix and slim-body matrix construction using the same cutting structure layout and PDC cutter grade.

The slim-body matrix construction demonstrates significant improvement in cost per foot for applications and is directly proportional to UCS. This feature is advantageous in interbedded applications, where formations fluctuate from hard to soft and vice versa along the drilled column. This new feature has since been standardized in matrix bits and is being rolled out across various applications with the intent of tackling more expensive drilling operations to show a greater reduction in cost per foot.
Crosslinked Polymeric Gels as Loss Circulation Materials: An Experimental Study
Authors: Hashmat M. D. , Sultan Abdullah S. , Rahman Saifur , Hussain S. M.
Published: July 2016

In an oil/gas well drilling operation, loss circulation of the drilling fluid in a thief zone is a major problem without a unique solution. This problem is mitigated by using Loss Circulation Materials (LCM). One method to counter this problem could be the use of gel forming polymer systems; that would gel and seal the undesired zones and prevent losses.

In this work interaction of a commercial grade hydrolyzed polyacrylamide (HPAM) and a HPAM derivative with polyethleneimine (PEI) was studied, for the possible use of these polymeric systems as a loss preventive and sealing agent. These studies involved the identification of the optimum polymer/crosslinker concentration followed by their thermal stability testing. Dynamic rheology tests were conducted on the systems in order to examine their pre and post-gelation behavior. Differential Scanning Calorimetry (DSC) was used to study the gelation kinetics of the systems. Selected systems were then tested on a see through flow system to observe their performance in a porous media.

It was observed that attaining an optimum polymer/crosslinker identification is an essential first step towards attaining a rigid and stable gel. At optimum concentrations stable gels were obtained. Gel strengths were greatly enhanced by increasing temperature and aging time. This was reflected in both the rheology and the DSC tests. The DSC experiments provided great insight into the gelation mechanics of the polymeric LCM systems. For the best two systems, 100% solution to gel conversion was attained in nearly three and a half hours of total ageing time at 100°C isothermal condition. The same gelants when tested on the see-through flow setup were able to successfully prevent mud loss in a zone having 36% porosity and 300 D permeability at room temperature and moderately high pressure conditions.

This paper will build on and substantiate the idea of utilizing cross-linked polymer gels as LCM. It will introduce the findings of a self-fabricated see through experimental setup that related the cross-linked polymeric LCM's behavior with differential pressure, in a porous media.