bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation on the Time Error of Detonation Acoustic in Process of Formation and Propagation
Authors: Xu Gui-yang , Wang Chun-guang , Hu Shao-qing , Gong Jian-Liang , Deng Zhe 
Published: August 2018

Abstract
The time error of detonation acoustic in process of detonation formation and propagation in a multi-cycle gas-liquid two-phase pulsed detonation engine is experimentally investigated. Results from the tests show that before the detonation wave escapes through the open-end of PDE tube, the maximum average arrival time error of detonation acoustic is achieved in the process of overdriven detonation. After detonation wave exists of PDE tube, arrival time error at 0 deg is greater than the other directivity angles in all distances and increases dramatically first and then almost stays at a certain value. The filling fraction has a major impact on the time error of detonation acoustic. With filling fraction increasing, there are increases in arrival time error and interval time error. Arrival time error with the highest filling fraction at 30 deg is much greater than other filling fraction. The convergent nozzle exhibits a marked suppression in the time error of detonation acoustic, where the maximum reductions of 62.02 percent and 56.13 percent are obtained in arrival time error and interval time error respectively.
Der verheißungsvolle Kontext und seine Leistungen bei der Erschließung von Wortbedeutungen
Authors: Haß Ulrike 
Published: August 2018

Abstract
The paper addresses the problems learners (L1) have to encounter while deducing word meaning from a given (written) context. The first part presents a theoretical model of context for that purpose. The main parts show the results of two approaches: First, a typical text from a schoolbook is examined to point out the principal potential of a text to deduce the meanings of words unknown to the reader. The second approach presents the results of an empirical study with more than 400 students, who were asked to mark unknown words and helpful context elements in a given text. The results of both approaches point at major and minor strategies of readers when looking for explanations of word meanings. Finally, a typical context seems to be much less helpful than teachers lean on.
An Innovative Experimental Setup for Characterizing Friction Fatigue during Cyclic Jacking of Piles in Dense Sand
Authors: Zhang Zitao , Wang Yu-Hsing 
Published: August 2018

AbstractIn this study, an innovative experimental setup for model pile tests was developed to characterize friction fatigue in sand during cyclic jacking. In the experimental setup, a high-performance precision electric linear actuator was used to control jacking of the model piles. P-wave tomographic imaging was used to characterize the associated changes in the distribution of the P-wave velocities in the soil, and tactile pressure sensors were utilized to monitor related variations in stresses in the soil surrounding the pile. Measurements obtained from the experiments allow us to explore the behavior of fiction fatigue from a different perspective, especially from the viewpoint of stress changes in the soil surrounding the pile. It was found that for a soil element surrounding the pile in a jacking cycle, the maximum values of the stationary radial and hoop stresses and the ultimate radial and hoop stresses in that soil element are reached when the pile penetrates to nearly the same depth, which is therefore defined as the transition depth. For the soil elements at the same depth, such a transition depth increases with increasing distance from the pile centerline. When the pile base gradually penetrates through the transition depth, these stresses in the soil elements surrounding the pile will exceed the peak value, which in turn leads to a reduction in the ultimate unit shear resistance (τf), giving rise to friction fatigue. Based on these experimental findings, a simple model is also proposed to explain friction fatigue.
Actitudes e ideologías lingüísticas de docentes de español: entre la corrección y el valor de la diversidad
Authors: Rodríguez Ana Constanza 
Published: August 2018

Este artículo presenta el análisis de los elementos que conforman las ideologías lingüísticas de docentes de español como lengua materna (ELM) recopiladas en ocho entrevistas a profesores de colegios de Bogotá en el marco de la investigación Actitudes e ideologías lingüísticas en el ejercicio docente. A partir de los relatos y entrevistas se presentan las tensiones que se generan en el ejercicio docente derivadas del encuentro entre las orientaciones pluralistas del discurso estatal en educación y las valoraciones que hacen los docentes sobre las variedades lingüísticas basadas en la noción de lengua estándar. Finalmente se retoman los postulados y aportes de la sociolingüística para proponer el fortalecimiento de la consciencia sociolingüística como estrategia de formación de estudiantes y formadores en aras de promover el reconocimiento y valoración de la diversidad lingüística en el aula.
Construcción de un Indice coincidente para la actividad económica Colombiana
Authors: Chudt Nicolás , Nieto Fabio H. 
Published: August 2018

Usando factores comunes de un conjunto de variables macroeconómicas y el enfoque de perfil coincidente para seleccionar uno de ellos, como el más cercano al estado de la economía, se propone en este trabajo un índice coincidente para la actividad económica Colombiana.
Adaptación y validación del cuestionario de motivos de participación para deportistas universitarios colombianos
Authors: Bustos Viviescas Brian Johan , Acevedo Mindiola Andrés Alonso , Barrera Pérez Jesús Fabián , Ramírez Pedraza Rubén Darío 
Published: August 2018

El objetivo del presente estudio fue adaptar y validar el cuestionario de motivos de participación (CMP) para deportistas universitarios colombianos (DUC). Para ello, se realizó un estudio descriptivo-exploratorio con enfoque mixto y una muestra a conveniencia de dieciséis hombres y trece mujeres con una edad comprendida entre los 17 y los 25 años pertenecientes a los grupos deportivos del Campus Villa del Rosario de la Universidad de Pamplona. Se hizo una adaptación del CMP que constó de 26 ítems. El análisis de la consistencia interna del instrumento y de los ítems (α de Cronbach), así como las medias y desviaciones típicas, se realizó mediante el paquete estadístico IBM SPSS V.22®. Los resultados obtenidos en el α de Cronbach manifestaron una alta fiabilidad (α>0,8), por lo cual no se eliminó ningún ítem del cuestionario adaptado. En conclusión, la adaptación del CMP presentó una alta fiabilidad en DUC.
El parkour como práctica cultural, un análisis desde las relaciones de poder
Authors: Gutiérrez Rodríguez Carlos Arturo 
Published: August 2018

Desde hace más de una década, en Colombia ha estado creciendo una comunidadde jóvenes que se dedica a la práctica del parkour, actividad física en la que se utiliza el cuerpo para desplazarse por los espacios urbanos y naturales, desarrollando diferentes tipos de movimientos y acrobacias. El presente artículo se aproxima a este como una nueva práctica cultural, que no ha sido suficientemente explorada por la academia colombiana, sobre la cual se resignifican los espacios y se construyen valores comunes entre los practicantes; quienes rompen con las estructuras de significado hegemónicas que se circunscriben sobre los espacios, para proponer una forma deinteracción diferente entre los sujetos y la ciudad.
Hábitos saludables, motivos y barreras en la realización de actividad física en estudiantes universitarios
Authors: Rodríguez Castellanos Fredy Alexander , Valencia Sandra Carolina , Gaitán Guzmán Erika María , González Rodríguez Sergio Andrés , León Díaz Juan David 
Published: August 2018

El principal objetivo de la investigación fue conocer los motivos, barreras y hábitos saludables asociados a la actividad física en estudiantes de Psicología en una universidad de Bogotá. La muestra final fue de 145 estudiantes seleccionados de forma aleatoria, a los cuales se les aplicó una lista de chequeo de hábitos de saludables, la Escala Revisada de Motivos para la Actividad Física y el Cuestionario de Percepción de Barreras para la Práctica de la Actividad Física. Se realizó un análisis descriptivo y posteriormente una regresión logística de la clasificación de activos e insuficientemente activos en relación con los motivos y barreras estudiadas. Los resultados muestran un mayor porcentaje de estudiantes clasificados como activos físicamente frente a otras investigaciones. Se corrobora la falta de motivación intrínseca y de tiempo como barreras más importantes; sin embargo, en cuanto a la predicción de ser clasificado como físicamente activo, el motivo de apariencia física cobra relevancia.
ANÁLISIS DE LAS CAPTURAS DE TIBURONES Y RAYAS EN LAS PESQUERÍAS ARTESANALES DE TÁRCOLES, PACÍFICO CENTRAL DE COSTA RICA
Authors: López Garro Andrés , Arauz Vargas Rándall , Zanella Ilena , Le Foulgo Loic 
Published: August 2018

Se analizaron las capturas de tiburones y rayas látigo realizadas por pescadores artesanales de Tárcoles en el Pacífico de Costa Rica, desde febrero del 2006 hasta febrero del 2007. Se observaron 415 faenas de pesca (línea de fondo, trasmallo y línea rayera): 340 correspondieron a observaciones de descarga y 75 (18.1%) a observaciones a bordo. Durante las descargas se analizaron 3299 tiburones y rayas látigo: el tiburón mamón enano (Mustelus henlei) dominó en la captura total (63.7%), seguido por el tiburón mamón común (Mustelus lunulatus) (16.7%), el tiburón picudo común (Rhizoprionodon longurio) 6.9% y el tiburón martillo común (Sphyrna lewini) 6.1%. A su vez, la raya látigo (D. longa) y el tiburón picudo fucsia (Nasolamia velox) representaron un 3.5% y 2.6% de la captura total, respectivamente. En los 75 viajes a bordo se capturó un total de 6.458 peces, de los cuales solo el 4.4% (240 individuos) fueron tiburones y rayas látigo. M. henlei fue nuevamente la especie más abundante (50.4%), le siguieron R. longurio (21.7%), D. longa (13.8), N. velox (5.8%), S. lewini (5.8%), y por último, M. lunulatus (2.5%). Debido a la estacionalidad y abundancia de tiburones mamones en la zona de Herradura, se recomienda un cierre técnico en enero-febrero y setiembre-octubre, meses con las mayores capturas. También se recomienda la protección de la zona del Peñón, ya que es utilizada por la raya látigo y por los juveniles del tiburón martillo.From February 2006 to February 2007, we analyzed shark and rays captures by the artisanal fishermen from Tárcoles, in the Pacific of Costa Rica. We observed 415 fishing operations (bottom line, gillnet and ray line): 340 dock landing observations and 75 (18.1%) on board observations. During the landing observations, we analyzed 3299 sharks and rays: the brown smooth hound (Mustelus henlei) was the most common species (63.7%), followed by the common smooth hound (Mustelus lunulatus) (16.7%), the Pacific sharpnose shark (Rhizoprionodon longurio) (6.9%) and the scalloped hammerhead shark (Sphyrna lewini) (6.1%). The longtail stingray (Dasyatis longa) and the whitenose shark (Nasolamia velox) represented the 3.5% and 2.6% of the total catch, respectively. During 75 fishing trips, we analyzed 6.458 fish individuals, of them only 4.4% (240 individuals) were sharks and longtail stingrays. Among these, M. henlei was also the most abundant species (50.4%), followed by R. longurio (21.7%), D. longa (13.8%), N. velox (5.8%), S. lewini (5.8%), and M. lunulatus (2.5%). Considering the seasonality and abundance of smooth hound sharks in Herradura, we recommend a technical closure during the higher catch months (January-February and September-October). Also, we recommend protecting the Peñón, which is inhabited by adults of longtail stingray and juvenile scalloped hammerhead sharks.
E-services evaluation criteria: the case of Azerbaijan
Authors: Yusifov Farhad , Gurbanli Aynur 
Published: August 2018

[full article in English]
The development of evaluation and effective public administration mechanisms are crucial for providing effective e-government services. The article explores the international expertise in the field of the e-service evaluation process. The organization and provision of e-services in government entities, as well as the evaluation regarding the organization and functioning of information systems, are carried out by the “ASAN service” system in Azerbaijan. The evaluation of the organization and functioning of e-services is conducted by considering three determined criteria: the level of digitalization and relevance, the level of information openness and accessibility, and the level of convenience of use. The evaluation process of e-services allows for improving the level of services and the development of feedback mechanisms; currently, much attention is attributed to the development of citizen-centered services.
(Egalitarinė) socializacija vaikystėje kaip sėkmingos moters karjeros biržinėse bendrovėse prielaida
Authors: Šidlauskienė Virginija , Pocevičienė Rasa 
Published: August 2018

[only abstract and keywords in English; full article, abstract and keywords in Lithuanian]
Globally, gender equality in the boards continues on an upward trajectory with slow but positive progress – in 2016, nearly 19% of seats on the boards of the largest companies globally were held by women, up from about 14% in 2012, with 3 percent of this growth coming in just the last two years (Zehnder 2017). A leading country in this matter, Norway, has introduced its quota law in 2007 requiring boards of listed companies to have a gender balance of at least 40/60. The ten years result of this quota happens to be an increase in female board members from 6 percent in 2002 to 42 percent in 2016 (CORE 2017). The EU also tries to push for a quota for women on company boards so as to address the slow progress toward gender equality in the senior ranks of publicly listed businesses. Although 62.7% of new university graduates are women (graduating with Master’s degrees – 66.5%, and 58.9% graduating with doctorates) in 2014, they are outnumbered by men in leadership positions in the corporate sector in the Lithuania. When looking at the top executive positions, there are no women CEOs (Chief Executive Officers) in the listed companies in Lithuania. From December 2013 to September 2014, the share of women on boards (executives) in Lithuania increased by 2.8% (Šidlauskienė, Pocevičienė 2015). Thus, the current moment offers a strategic opportunity to proactively enhance gender equality and prevent any more widening of the gender and skills gaps. This research was aimed to analyze the theoretical aspects of gender balance on the executive boards of the listed companies and to explore childhood socialization predictors that impede (or facilitate) the increase of successful participation of women in decision-making bodies in the listed Lithuanian companies. The successful career women, or the high flyers theory, has been used to argue that childhood socialization, education, personality and motivation indicated personal traits needed for board level roles (White et al. 1992). Second, the individual career capital theory argues that taking up such a role consists of three ways of knowing: knowing-how, knowing-whom and knowing-why. Research results shows that egalitarian childhood socialization influences successful women’s careers in the listed company boards. Certain individual characteristics, such as integrity and honesty, accountability, result-orientation, being a team player, a relationship builder, a good listener and communicator, and genuine commitment and energy, are in demand in such companies as PANDORA A/S, Spencer Stuart, Board Succession etc.
Studentų darbų mokslinio stiliaus trūkumai
Authors: Macienė Jurgita 
Published: August 2018

[only abstract and keywords in English; full article, abstract and keywords in Lithuanian]
The academic writing style tends to have quite clearly described requirements. University students use academic writing when doing course papers and theses. The goal of this article is to analyze the drawbacks of the academic style in examples of students’ works, identify the ways in which they are inappropriate and to suggest options for correcting the drawbacks. When reading the course papers and final theses, one can notice that students do not follow the foundational requirements of academic writing – such as clarity, accuracy, conciseness and the logical approach. Instead, they tend to use lexical ambiguity when forming syntax constructions, confuse the coherent reason-consequence relationship, tend to extensively use language that is not very informative or start a sentence focused on one idea and complete it by empasizing a different one. Language mistakes and typographical errors are also noticeable.
Factors Influencing Access to Reproductive Health Information Services among Young Aged 15-24 in Garissa Municipality, Kenya
Authors: Adan Fatuma I. , Githae Dr. M.N. 
Published: August 2018

Young people face severe threats to their health and general well being. They are vulnerable to sexual assault and prostitution, too-early pregnancy and childbearing, unsafe abortion, malnutrition, female genital cutting, infertility, anemia, and reproductive tract infections (RTIs) including STIs and HIV/AIDS (NCPD, 2006). Close to a half of women aged 15-19 in Kenya are sexually active and by age 20-24 years, almost all (90%) are sexually exposed, and that 84% of the women aged 15-19 are single girls, then a large proportion of never-married girls are in their sexually active period (KDHS,2003).
This study was designed to look into demographic, economic, cultural, health factors and the knowledge, attitude and practices influencing the access to Sexual Reproductive Health (SRH) information services amongst the youth of Garissa. The qualitative and quantitative data were collected through structured face to face interviews, focus group discussions and key informant. Data was analyzed using SPSS (version 17). The data from the qualitative methods were analyzed by using the thematic framework analysis. Independent variables influencing the access to SRH information among the youth were determined using multiple logistic regressions.
In conclusion the overall access to SRH information by the youth in Garissa Municipality was low and was mostly influenced by the economic factors, cultural, religious and societal norms that marginalize the youth and the overall lack of access and programs to address youth friendly SRH information. To address the challenges in the access to youth friendly reproductive health information in this setting it is our recommendation that improve the Clinical services to offer the youths with Contraceptive and STI prevention services, antenatal, perinatal, and postnatal care, STI diagnosis and treatment and lastly empower youths with RH and rights and HIV information and life skills education through community outreach programmes.
Design and Fabrication of Fiber Reinforced Boat in Eritrea
Authors: Mohan Thamizhmani , Araya Zereghaber 
Published: August 2018

Transportation through water body is the cheapest and the most important way of transportation system in human life. Eritrea has a wide range of coastal area along Red Sea and it is obvious that those people who live in the coastal area were used to fishing. Wood is one of the easiest and ancient materials that have been utilized for the construction of boats and it also remains as a favorite one for many professionals, but the boats which were constructed of woods were much heavier in their light weight, therefore they couldn't carry more loads. Scarcity and high price of the timber along with the high annual repair and maintenance cost will reduce the income of the boatmen and also increased consumption of timber will results in faster deforestation.
In this situation, various alternative materials like ferrocement, aluminium, fibre reinforced glass and fibre reinforced concrete has been used as an alternative material for construction of boats. So, our first work in the fabrication of the boat is to choose the alternative material for fabricating a vessel.
Plywood has lots of advantages like they are stiffer than boards of equal thickness of regular lumber. Due to the stiffness of the plywood panels, weight can be saved by replacing the regular lumbar by plywood, which is an important problem faced in both power and sail boats. Fiber glass along with resins has many advantages like thermal insulation, electrical insulation, reinforcement, heat and corrosion resistant and easily recyclable for future purposes.
This technique of fabrication will give good results by reducing the problems with leakage and bio fouling of hull surface due to marine growth such as barnacles and in turn which increases the life span of the hull surface of the boats. So this work will be useful for those communities who are working with the boats for their transportation and fishing activities and it also improves the standard of the fisherman and their activities. By design and constructing a boat with plywood and FRG, the quality and standard of the boat will be improved along with a certain degree of safety. As a student of marine engineering department, this research work increase the knowledge about design software’s like solid works and delft ship, design parameters of a vessel and all the fabrication procedures of the boat by using fiber reinforced glass in combination with plywood.
HETEROGENEOUS ELECTRO FENTON PROCESS FOR TEXTILE WASTEWATER TREATMENT: APPLICATION OF Fe3O4-Mn3O4 AS A CATALYST
Authors: Dat Duc Nguyen Duc 
Published: August 2018

To produce quality textile products, many stable synthetic dyes are invented. However, textile wastewater discharged into the environment contains a large amount of dyes which are bio-recalcitrants and stable to heat and solar radiation. These toxic contaminants impact negatively the environment for a long time and poison plants, animals, and human. In this study, Heterogeneous Electro Fenton process with Fe3O4-Mn3O4 as a catalyst was used for textile wastewater treatment. Graphite electrodes were chosen for their stability and good conductivity. Three operating factors greatly affected the removal efficiency are current density, pH and catalyst dosage. Response surface methodology was applied to find empirical mathematical models for these factors, then find an accordant operating condition for treatment which provides high removal efficiency and low operating cost. Investigated ranges scaled in previous studies were: current density (10 – 20 mA/cm2), pH (3 – 5), and catalyst dosage (0.5 – 1.5 g/l). At current density of 17.03 mA/cm2, pH of 3.77, catalyst dosage of 1.17 g/l, the treatment reached its optimum condition, COD and Color removal efficiencies were 93.3 % and 99.2 %, respectively, where COD and Color values in the effluent are 56 mg/l and 16 Pt-Co.
THE STUDY ON OPTIMIZATION OF COPPER LEACHING FROM WASTE PCBs BY USING RESPONSE SURFACE METHODOLOGY
Authors: Ngoc Mai Tran Thi 
Published: August 2018

Recycling printed circuit boards (PCBs) is an important solution not only to treat hazardous waste but also to recover valuable materials. This research focus on optimizing the leaching copper process from waste PCBs to recycle. This process was performed in Fe2(SO4)3 solution at room temperature and using H2O2 as an oxidant. For optimization, response surface methodology was used to investigate the different parameters, including Fe2(SO4)3 concentration, volume of H2O2 addition and leaching time. Design Expert 10.0 software was applied to design the experiments and calculate the regression equation of the response function. As a result, a model was established which is compatible with the experimental data at the correlation coefficient (R2) of 0.99. The optimal conditions were identified as Fe2(SO4)3 concentration of 0.35 M, volume of H2O2 addition at 10 mL and leaching time of 10 h. Under this condition, leaching efficiency of 90.5 percent was achieved. After leaching, copper was recovered from extract solution by electrochemical technology with the efficiency of 85 percent. The results from this study hence proposed a very promising method for recycling copper in PCBs.