Search results for: intermediate level

Authors: Moumen Abdelhafidh, Stribu Bogdan, Laboureur Delphine, Gallant Johan, Hendrick Patrick

Abstract:

This study is part of an ongoing effort to improve the understanding of phenomena occurring during the intermediate ballistic phase, such as muzzle flows. A thorough comprehension of muzzle flow fields is essential for optimizing muzzle device and projectile design. This flow characterization has heretofore been almost entirely limited to local and intrusive measurement techniques such as pressure measurements using pencil probes. Consequently, the body of quantitative experimental data is limited, so is the number of numerical codes validated in this field. The objective of the work presented here is to demonstrate the applicability of the Particle Image Velocimetry (PIV) technique in the challenging environment of the propellant flow of a .300 blackout weapon to provide accurate velocity measurements. The key points of a successful PIV measurement are the selection of the particle tracer, their seeding technique, and their tracking characteristics. We have experimentally investigated the aforementioned points by evaluating the resistance, gas dispersion, laser light reflection as well as the response to a step change across the Mach disk for five different solid tracers using two seeding methods. To this end, an experimental setup has been performed and consisted of a PIV system, the combustion chamber pressure measurement, classical high-speed schlieren visualization, and an aerosol spectrometer. The latter is used to determine the particle size distribution in the muzzle flow. The experimental results demonstrated the ability of PIV to accurately resolve the salient features of the propellant flow, such as the under the expanded jet and vortex rings, as well as the instantaneous velocity field with maximum centreline velocities of more than 1000 m/s. Besides, naturally present unburned particles in the gas and solid ZrO₂ particles with a nominal size of 100 nm, when coated on the propellant powder, are suitable as tracers. However, the TiO₂ particles intended to act as a tracer, surprisingly not only melted but also functioned as a combustion accelerator and decreased the number of particles in the propellant gas.

Keywords: intermediate ballistic, muzzle flow fields, particle image velocimetry, propellant gas, particle size distribution, under expanded jet, solid particle tracers

Procedia PDF Downloads 138

Authors: Tannistha Dasgupta

Abstract:

This study explores the aspects of second language (L2) spoken fluency that are related to L2 linguistic knowledge and processing skill. It draws on Levelt’s ‘blueprint’ of the L2 speaker which discusses the cognitive issues underlying the act of speaking. However, L2 speaking assessments have largely neglected the underlying mechanism involved in language production; emphasis is given on the relationship between subjective ratings of L2 speech sample and objectively measured aspects of fluency. Hence, in this study, the relation between L2 linguistic knowledge and processing skill i.e. Cognitive Fluency (CF), and objectively measurable aspects of L2 spoken fluency i.e. Utterance Fluency (UF) is examined. The participants of the study are L2 learners of English, studying at high school level in Hyderabad, India. 50 participants with intermediate level of proficiency in English performed several lexical retrieval tasks and attention-shifting tasks to measure CF, and 8 oral tasks to measure UF. Each aspect of UF (speed, pause, and repair) were measured against the scores of CF to find out those aspects of UF which are reliable indicators of CF. Quantitative analysis of the data shows that among the three aspects of UF; speed is the best predictor of CF, and pause is weakly related to CF. The study suggests that including the speed aspect of UF could make L2 fluency assessment more reliable, valid, and objective. Thus, incorporating the assessment of psycholinguistic mechanisms into L2 spoken fluency testing, could result in fairer evaluation.

Keywords: attention-shifting, cognitive fluency, lexical retrieval, utterance fluency

Procedia PDF Downloads 689

Authors: Hui Wang, Huan Zhang

Abstract:

This study uses systematic review and qualitative comparative analysis methods to comprehensively inquire about the recent street-level policy entrepreneurship research, to identify the characteristics and lessons we can learn from 20 years of street-level policy entrepreneurship literature, and the relations between political contexts and street-level policy entrepreneurs’ strategies. Using data from a systematic review of street-level policy entrepreneurship literature, we identify the sub-components of different political contexts and core strategies of street-level policy entrepreneurs and estimate the configurational relations between different political settings and street-level policy entrepreneurs’ strategies. Our results show that street-level policy entrepreneurs display social acuity, define the problem, and build team strategies when policy or political streams dominate. Street-level policy entrepreneurs will use lead-by-example strategies when both policy and political streams dominate. Furthermore, street-level policy entrepreneurs will use bureaucratic strategies, even if no stream dominates in the political context.

Keywords: policy entrepreneurs, qualitative comparative analysis, street-level bureaucracy, systematic review

Procedia PDF Downloads 84

Authors: Rebecca Dunne, Cormac Small, Geraldine O'Boyle, Nazir Ibrahim, Anisha

Abstract:

Prostate cancer is the most common cancer among men, excluding non-melanoma skin cancers. It is estimated that approximately 12% of men will develop prostate cancer during their lifetime. Patients with intermediate, high risk, and very-high risk prostate cancer often undergo a combination of radiation treatments. These treatments include external beam radiotherapy with a low-dose rate or high-dose rate brachytherapy boost, often with concomitant androgen deprivation therapy. The literature on follow-up of patients that receive brachytherapy is scarce, particularly follow-up of patients that undergo high-dose rate brachytherapy. This retrospective study aims to investigate the biochemical failure and toxicities associated with triple therapy and external beam radiotherapy given in combination with brachytherapy. Reported toxicities and prostate specific antigen (PSA) were retrospectively evaluated in eighty patients that previously underwent external beam radiotherapy with a low-dose rate or high dose-rate brachytherapy boost. The severity of toxicities were correlated with intra-operative dosing during brachytherapy on ultrasound and CT scan. The results of this study will provide further information for clinicians and patients when considering treatment options.

Keywords: toxicities, combination, brachytherapy, intra-operative dosing, biochemical failure

Procedia PDF Downloads 209

Authors: Bing-Qing Lu, Hui-Tzu Min

Abstract:

Recent research, supported by sociocultural theory, has shown that collaborative writing in the second language (L2) contexts afford students opportunities to interact with each other to co-construct knowledge during the co-composing process. To date, much research on pair interaction in L2 collaborative writing settings has centered on intermediate and advanced learners by using static categorization of pair interaction patterns. Little is known about the fluid nature of pair interaction during collaborative writing, especially among low-proficiency learners. This study, thus, is aimed to explore the interaction dynamics of low-proficiency L2 learners during collaborative writing via examining the interaction pattern, focus of interaction, and the language related episodes (LREs) of 5 low-proficiency L2 writers from Taiwan. Employing a micro-level functional analytical method to capture the changing nature of pair interaction dynamics, the researchers calculated the number of characters/words produced by each pair member during CW and then classified their utterances into four task related-aspects--content, organization, language use, and task management--to determine each pair member's relative contribution to different dimensions of the evolving text. The LREs were also identified and examined. The results show that, of the five pairs, three pairs changed their interaction patterns when discussing different aspects of writing. Regarding the focus of their interaction, all five pairs paid attention to content most, followed by language use, task management, and organization. They were able to successfully resolve the majority of language issues (75.2%) in LREs and use the correct forms in their writing. These findings lend support to the fluid nature of pairs’ interactions and the changing roles of L2 learners in collaborative writing and highlighted the necessity of examining learners’ interaction patterns from a micro-level perspective. These findings also support previous research that low-proficiency pairs are able to correctly revolve 2/3 of their produced LREs, suggesting that collaborative writing may also be suitable for L2 low-proficiency learners.

Keywords: collaborative writing, low-proficiency L2 learners, micro-level functional analysis, pair interaction pattern

Procedia PDF Downloads 107

Authors: Somchai Buaroong

Abstract:

This research attempted to study information system success in dimensions of the user satisfaction level and to find the association between the independent factors of the user experiences, user knowledge, and user attitude. The study sample was selected using simple random sampling that comprised of 190 users who had used the Bangkok HIS. The data were reported from 165 questionnaires. The results found that the user satisfaction was at a moderate level, user satisfaction on the information quality and system quality was at a moderate level, while satisfaction on service quality was at a high level. The computer knowledge of the user was at a moderate level, and the user attitude was at a positive level. The participation of the user was at a low level and the participation in decision and in evaluation was at a low level; however participation in implementation and in benefit was at a moderate.

Keywords: information system success, hospital information system, user attitude, user satisfaction

Procedia PDF Downloads 295

Authors: Mohd Aftar Abu Bakar, Noratiqah Mohd Ariff, Abdul Aziz Jemain

Abstract:

Storm Event Analysis (SEA) provides a method to define rainfalls events as storms where each storm has its own amount and duration. By modelling daily probability of different types of storms, the onset, offset and cycle of rainfall seasons can be determined and investigated. Furthermore, researchers from the field of meteorology will be able to study the dynamical characteristics of rainfalls and make predictions for future reference. In this study, four categories of storms; short, intermediate, long and very long storms; are introduced based on the length of storm duration. Daily probability models of storms are built for these four categories of storms in Peninsular Malaysia. The models are constructed by using Bernoulli distribution and by applying linear regression on the first Fourier harmonic equation. From the models obtained, it is found that daily probability of storms at the Eastern part of Peninsular Malaysia shows a unimodal pattern with high probability of rain beginning at the end of the year and lasting until early the next year. This is very likely due to the Northeast monsoon season which occurs from November to March every year. Meanwhile, short and intermediate storms at other regions of Peninsular Malaysia experience a bimodal cycle due to the two inter-monsoon seasons. Overall, these models indicate that Peninsular Malaysia can be divided into four distinct regions based on the daily pattern for the probability of various storm events.

Keywords: daily probability model, monsoon seasons, regions, storm events

Procedia PDF Downloads 322

Authors: Kaine Gulozer

Abstract:

A strong methodological conception in the practice of teaching, content, and language integrated learning (CLIL) is adapted to boost efficiency in the second language (L2) instruction with a range of proficiency levels. This study aims to investigate whether the incorporation of two different mediums of meaningful CLIL reading activities (in-school and out-of-school settings) influence L2 students’ development of comprehension skills differently. CLIL based instructional methodology was adopted and total of 50 preparatory year students (N=50, 25 students for each proficiency level) from two distinct language proficiency learners (elementary and intermediate) majoring in engineering faculties were recruited for the study. Both qualitative and quantitative methods through a post-test design were adopted. Data were collected through a questionnaire, a reading comprehension test and a semi-structured interview addressed to the two proficiency groups. The results show that both settings in relation to the development of reading comprehension are beneficial, whereas the impact of the reading activities conducted in school settings was higher at the elementary language level of students than that of the one conducted out-of-class settings based on the reported interview results. This study suggests that the incorporation of meaningful CLIL reading activities in both settings for both proficiency levels could create students’ self-awareness of their language learning process and the sense of ownership in successful improvements of field-specific reading comprehension. Further potential suggestions and implications of the study were discussed.

Keywords: content and language integrated learning, in-school setting, language proficiency, out-of-school setting, reading comprehension

Procedia PDF Downloads 122

Authors: M. Hossain, H. P. Zhu, A. B. Yu

Abstract:

This paper presents a numerical investigation of regime transition of flow of ellipsoidal particles and a comparison with that of spherical particle assembly. Particle assemblies constituting spherical and ellipsoidal particle of 2.5:1 aspect ratio are examined at separate instances in similar flow conditions in a shear cell model that is numerically developed based on the discrete element method. Correlations among elastically scaled stress, kinetically scaled stress, coordination number and volume fraction are investigated, and show important similarities and differences for the spherical and ellipsoidal particle assemblies. In particular, volume fractions at points of regime transition are identified for both types of particles. It is found that compared with spherical particle assembly, ellipsoidal particle assembly has higher volume fraction for the quasistatic to intermediate regime transition and lower volume fraction for the intermediate to inertial regime transition. Finally, the relationship between coordination number and volume fraction shows strikingly distinct features for the two cases, suggesting that different from spherical particles, the effect of the shear rate on the coordination number is not significant for ellipsoidal particles. This work provides a glimpse of currently running work on one of the most attractive scopes of research in this field and has a wide prospect in understanding rheology of more complex shaped particles in light of the strong basis of simpler spherical particle rheology.

Keywords: DEM, granular rheology, non-spherical particles, regime transition

Procedia PDF Downloads 249

Authors: Nam Chol Yu, GyongIl Chu, HoJong Ri

Abstract:

Using DLTS (Deep-level transient spectroscopy) measurement techniques, we determined the dominant recombination center levels (defects of both A and B) in gold and platinum doped n-type silicon. Also, the injection and temperature dependence of the Shockley-Read-Hall (SRH) carrier lifetime was studied under low-level injection and high-level injection. Here measurements show that the dominant level under low-level injection located at EC-0.25 eV (A) correlated to the Pt+G1 and the dominant level under high-level injection located at EC-0.54 eV (B) correlated to the Au+G4. Finally, A and B are the same dominant levels for controlling the lifetime in gold-platinum doped n-silicon.

Keywords: recombination center level, lifetime, carrier lifetime control, Gold, Platinum, Silicon

Procedia PDF Downloads 42

Authors: Gregory Kelly, Gary Chai, Sittampalam Manoharan, Deborah Delaney

Abstract:

A Structural Number (SN) can be calculated for a road pavement from the properties and thicknesses of the surface, base course, sub-base, and subgrade. Historically, the cost of collecting structural data has been very high. Data were initially collected using Benkelman Beams and now by Falling Weight Deflectometer (FWD). The structural strength of pavements weakens over time due to environmental and traffic loading factors, but due to a lack of data, no structural deterioration curve for pavements has been implemented in a Pavement Management System (PMS). International Roughness Index (IRI) is a measure of the road longitudinal profile and has been used as a proxy for a pavement’s structural integrity. This paper offers two conceptual methods to develop Pavement Structural Deterioration Curves (PSDC). Firstly, structural data are grouped in sets by design Equivalent Standard Axles (ESA). An ‘Initial’ SN (ISN), Intermediate SN’s (SNI) and a Terminal SN (TSN), are used to develop the curves. Using FWD data, the ISN is the SN after the pavement is rehabilitated (Financial Accounting ‘Modern Equivalent’). Intermediate SNIs, are SNs other than the ISN and TSN. The TSN was defined as the SN of the pavement when it was approved for pavement rehabilitation. The second method is to use Traffic Speed Deflectometer data (TSD). The road network already divided into road blocks, is grouped by traffic loading. For each traffic loading group, road blocks that have had a recent pavement rehabilitation, are used to calculate the ISN and those planned for pavement rehabilitation to calculate the TSN. The remaining SNs are used to complete the age-based or if available, historical traffic loading-based SNI’s.

Keywords: conceptual, pavement structural number, pavement structural deterioration curve, pavement management system

Procedia PDF Downloads 521

Authors: Han Xiao

Abstract:

The development of nanomedicines has recently achieved several breakthroughs in the field of cancer treatment; however, the biocompatibility and targeted burst release of these medications remain a limitation, which leads to serious side effects and significantly narrows the scope of their applications. The self-assembly of intermediate filament protein (IFP) peptides was triggered by a hydrophobic cation drug 7-amino actinomycin D (7-AAD) to synthesize pH-activatable nanoparticles (NPs) that could simultaneously locate tumors and produce antitumor effects. The designed IFP peptide included a target peptide (arginine–glycine–aspartate), a negatively charged region, and an α-helix sequence. It also possessed the ability to encapsulate 7-AAD molecules through the formation of hydrogen bonds and hydrophobic interactions by a one-step method. 7-AAD molecules with excellent near-infrared fluorescence properties could be target delivered into tumor cells by NPs and released immediately in the acidic environments of tumors and endosome/lysosomes, ultimately inducing cytotoxicity by arresting the tumor cell cycle with inserted DNA. It is noteworthy that the IFP/7-AAD NPs tail vein injection approach demonstrated not only high tumor-targeted imaging potential, but also strong antitumor therapeutic effects in vivo. The proposed strategy may be used in the delivery of cationic antitumor drugs for precise imaging and cancer therapy.

Keywords: 7-amino actinomycin D, intermediate filament protein, nanoparticle, tumor image

Procedia PDF Downloads 122

Authors: Malgorzata Rudnicka, Waldemar Karcz

Abstract:

Introduction: Naphthoquinones are widely occurring organic compounds produced by bacteria, fungi, and plants. They can act as the functional components of biochemical systems (plastoquinone) as well as biologically active substances, which have a negative impact on environmental processes. Naphthoquinones seem to act through two mechanisms: a covalent modification of biological molecules at their nucleophilic sites or by generation of reactive oxygen species (ROS) connected with redox cycling. Investigating the effect of naphthoquinones (1,4-naphthoquinone, lawsone and naphthazarin) on the elongation growth, membrane potential and the level of oxidative stress of maize cells seems to be important due to the possibility of using these substances as herbicides. Methods: All experiments were performed on etiolated maize coleoptile segments. Simultaneous measurements of elongation growth and pH of the incubation medium were carried out using an angular position transducer, allowing a precise record of the growth kinetics. To compare the oxidative stress level induced by all tested naphthoquinones, the changes in malondialdehyde content, as well as superoxide dismutase and catalase activities were measured. In order to measure the membrane potential of parenchymal cells the standard electrophysiology technique was used. Results: Naphthoquinones such as: 1,4-naphthoquinone, lawsone and naphthazarin were studied. It was found that all of the naphthoquinones diminished the growth of the maize coleoptile cells depending on the type of naphthoquinones and their concentration. Interestingly, naphthazarin at the intermediate concentration was less toxic compared to the others. In addition, the effect of naphthoquinones on the oxidative stress was dependent on their concentration as well. Superoxide dismutase and catalase activities were changed in the presence of higher concentrations of naphthoquinones. Similar interrelations were observed for membrane potential changes. Conclusion: It can be concluded that naphthoquinones tested differ in their toxic effect on the growth of maize coleoptile cells. Furthermore, naphthoquinones can be distinguish considering the oxidative stress level and membrane potential changes. The results presented here give new insight into the possible opportunities of practical usage of naphthoquinones for herbicides improvement.

Keywords: growth rate, membrane potential, naphthoquinones, oxidative stress

Procedia PDF Downloads 258

Authors: Hamid Goharnejad, Amir Hossein Eghbali

Abstract:

Recent investigations have demonstrated the global sea level rise due to climate change impacts. In this study climate changes study the effects of increasing water level in the strait of Hormuz. The probable changes of sea level rise should be investigated to employ the adaption strategies. The climatic output data of a GCM (General Circulation Model) named CGCM3 under climate change scenario of A1b and A2 were used. Among different variables simulated by this model, those of maximum correlation with sea level changes in the study region and least redundancy among themselves were selected for sea level rise prediction by using stepwise regression. One models of Discrete Wavelet artificial Neural Network (DWNN) was developed to explore the relationship between climatic variables and sea level changes. In these models, wavelet was used to disaggregate the time series of input and output data into different components and then ANN was used to relate the disaggregated components of predictors and predictands to each other. The results showed in the Shahid Rajae Station for scenario A1B sea level rise is among 64 to 75 cm and for the A2 Scenario sea level rise is among 90 to 105 cm. Furthermore the result showed a significant increase of sea level at the study region under climate change impacts, which should be incorporated in coastal areas management.

Keywords: climate change scenarios, sea-level rise, strait of Hormuz, forecasting

Procedia PDF Downloads 245

Authors: Mohammad Kousara, Françoise Dumas, Rama Ibrahim, Joëlle Dubois, Joël Raingeaud

Abstract:

Suberosanes are a small group of marine natural sesquiterpenes discovered since 1996 by Boyd, Sheu and Qi from three gorgonians. Their skeleton was previously found in quadranes produced by the terrestrial fungus Aspergillus terreus. Up to date, eleven suberosanes are described from which (-)-suberosanone and (-)-suberosenol A are reaching the picomolar cytotoxicity level on human solid tumors cell lines. Due to their impressive cytotoxic properties and their limited availability, we undertook an asymmetric synthesis of the most active members of this family in order to get insight into their absolute configurations and their biological properties. The challenge of their synthesis is the regio- and stereoselective elaboration of the compact bridged tricyclic skeleton with up to five all adjacent asymmetric centers, including a central quaternary carbon one. Our strategy is based on an aza-ene-synthesis key step which is regio-and stereo-controlled by the choice of a chiral amine enantiomer. it approach is concise and flexible, the enantiopur ABC tricyclic intermediate that have been synthesized being the common precursor of suberosanes.

Keywords: suberosanes, asymmetric synthesis, sesquiterpenes, quadranes

Procedia PDF Downloads 64

Authors: Yaru Meng

Abstract:

The study contributes to the small but growing literature around computerized approaches to dynamic assessment (C-DA), wherein individual items are accompanied by mediating prompts. Mediation in the current computerized dynamic listening assessment (CDLA) was informed by an attribute-based mediation model (AMM) that identified the underlying L2 listening cognitive abilities and associated descriptors. The AMM served to focus mediation during C-DA on particular cognitive abilities with a goal of specifying areas of learner difficulty. 86 low-intermediate L2 English learners from a university in China completed three listening assessments, with an experimental group receiving the CLDA system and a control group a non-dynamic assessment. As an assessment, the use of the AMM in C-DA generated detailed diagnoses for each learner. In addition, both within- and between-group repeated ANOVA found greater gains at the level of specific attributes among C-DA learners over the course of a 5-week study. Directions for future research are discussed.

Keywords: computerized dynamic assessment, effectiveness, English as foreign language listening, attribute-based mediation model

Procedia PDF Downloads 187

Authors: Z. W. Zhong, C. Xu, W. K. Choi

Abstract:

To build a thin fan-out wafer-level package, the package had to be ground to a thin level. In this work, the influence of the grinding processes on the strength of the fan-out wafer-level packages was investigated. After different grinding processes, all specimens were placed on a three-point-bending fixture installed on a universal tester for three-point-bending testing, and the strength of the fan-out wafer-level packages was measured. The experiments revealed that the average flexure strength increased with the decreasing surface roughness height of the fan-out wafer-level package tested. The grinding processes had a significant influence on the strength of the fan-out wafer-level packages investigated.

Keywords: FOWLP strength, surface roughness, three-point bending, grinding

Procedia PDF Downloads 258

Authors: Deborah Eric, Abbas Ahmad Khan

Abstract:

Lead halide perovskites quantum dots have attracted immense scientific and technological interest for successful photovoltaic applications because of their remarkable optoelectronic properties. In this paper, we have simulated CsMAPbI3-xBrx based quantum dots to implement their use in intermediate band solar cells (IBSC). These types of materials exhibit optical and electrical properties distinct from their bulk counterparts due to quantum confinement. The conceptual framework provides a route to analyze the electronic properties of quantum dots. This layer of quantum dots optimizes the position and bandwidth of IB that lies in the forbidden region of the conventional bandgap. A three-dimensional MAPbI3 quantum dot (QD) with geometries including spherical, cubic, and conical has been embedded in the CsPbBr3 matrix. Bound energy wavefunction gives rise to miniband, which results in the formation of IB. If there is more than one miniband, then there is a possibility of having more than one IB. The optimization of QD size results in more IBs in the forbidden region. One band time-independent Schrödinger equation using the effective mass approximation with step potential barrier is solved to compute the electronic states. Envelope function approximation with BenDaniel-Duke boundary condition is used in combination with the Schrödinger equation for the calculation of eigen energies and Eigen energies are solved for the quasi-bound states using an eigenvalue study. The transfer matrix method is used to study the quantum tunneling of MAPbI3 QD through neighbor barriers of CsPbI3. Electronic states are computed using Schrödinger equation with effective mass approximation by considering quantum dot and wetting layer assembly. Results have shown the varying the quantum dot size affects the energy pinning of QD. Changes in the ground, first, second state energies have been observed. The QD is non-zero at the center and decays exponentially to zero at boundaries. Quasi-bound states are characterized by envelope functions. It has been observed that conical quantum dots have maximum ground state energy at a small radius. Increasing the wetting layer thickness exhibits energy signatures similar to bulk material for each QD size.

Keywords: perovskite, intermediate bandgap, quantum dots, miniband formation

Procedia PDF Downloads 147

Authors: Hamed Homaei, Iraj Mahdavi, Ali Tajdin

Abstract:

One of the main concerns of miners is to increase the quality level of their products because the mining metals price depends on their quality level; however, increasing the quality level of these products has different costs at different levels of the supply chain. These costs usually increase after extractor level. This paper studies the coordination issue of a decentralized three-level supply chain with one supplier (extractor), one mineral processor and one manufacturer in which the increasing product quality level cost at the processor level is higher than the supplier and at the level of the manufacturer is more than the processor. We identify the optimal product quality level for each supply chain member by designing a revenue sharing contract. Finally, numerical examples show that the designed contract not only increases the final product quality level but also provides a win-win condition for all supply chain members and increases the whole supply chain profit.

Keywords: three-stage supply chain, product quality improvement, channel coordination, revenue sharing

Procedia PDF Downloads 166

Authors: Yi-Hsiu Lai

Abstract:

The present study aimed to elucidate the lexical-semantic processing for Chinese as second language (CSL) learners. Twenty L1 speakers of Chinese and twenty CSL learners in Taiwan participated in a picture naming task and a category fluency task. Based on their Chinese proficiency levels, these CSL learners were further divided into two sub-groups: ten CSL learners of elementary Chinese proficiency level and ten CSL learners of intermediate Chinese proficiency level. Instruments for the naming task were sixty black-and-white pictures: thirty-five object pictures and twenty-five action pictures. Object pictures were divided into two categories: living objects and non-living objects. Action pictures were composed of two categories: action verbs and process verbs. As in the naming task, the category fluency task consisted of two semantic categories – objects (i.e., living and non-living objects) and actions (i.e., action and process verbs). Participants were asked to report as many items within a category as possible in one minute. Oral productions were tape-recorded and transcribed for further analysis. Both error types and error frequency were calculated. Statistical analysis was further conducted to examine these error types and frequency made by CSL learners. Additionally, category effects, pictorial effects and L2 proficiency were discussed. Findings in the present study helped characterize the lexical-semantic process of Chinese naming in CSL learners of different Chinese proficiency levels and made contributions to Chinese vocabulary teaching and learning in the future.

Keywords: lexical-semantic processing, Mandarin Chinese, naming, category effects

Procedia PDF Downloads 442

Authors: Muhammad Mooneeb Ali

Abstract:

Institutions, where religious knowledge is given are known as madrassas. They also give formal education along with religious education. This study will be a pioneer to explore if MALL can be beneficial for madrassa students or not in formal educational situations. For investigation, an experimental study was planned in Punjab where the sample size was 100 students, 10 each from 10 different madrassas of Punjab, who are studying at the intermediate level (i.e., 11th grade). The madrassas were chosen through a convenient sampling method, whereas the learners were chosen by a simple random sampling method. A pretest was conducted, and on the basis of the results, the learners were divided into two equal groups (experimental and controlled). After two months of treatment, a posttest was conducted, and the results of both groups were compared. The results indicated that the performance of the experimental group was significantly better than the control one. This indicates that MALL elevates the performance of Madrassa students.

Keywords: english language learners, madrassa students, formal education, mobile assisted language learning (MALL), Pakistan.

Procedia PDF Downloads 52

Authors: Chandra Gupt Porwal, Preeti C. Porwal

Abstract:

Transient data reveals much about the machine's condition that steady-state data cannot. New technologies make this information much more available for evaluating the mechanical integrity of a machine train. Recent surveys at various stations indicate that simplicity is preferred over completeness in machine audits throughout the power generation industry. This is most clearly shown by the number of rotating machinery predictive maintenance programs in which only steady-state vibration amplitude is trended while important transient vibration data is not even acquired. Efforts have been made to explain what transient data is, its importance, the types of plots used for its display, and its effective utilization for analysis. In order to demonstrate the value of measuring transient data and its practical application in rotating machinery for resolving complex and persistent issues with turbine generators, the author presents a few case studies that highlight the presence of rotor instabilities due to the shaft moving towards the bearing centre in a 100 MM LMZ unit located in the Northern Capital Region (NCR), heavy misalignment noticed—especially after 2993 rpm—caused by loose coupling bolts, which prevented the machine from being synchronized for more than four months in a 250 MW KWU unit in the Western Region (WR), and heavy preload noticed at Intermediate pressure turbine (IPT) bearing near HP- IP coupling, caused by high points on coupling faces at a 500 MW KWU unit in the Northern region (NR), experienced at Indian power plants.

Keywords: transient data, steady-state-data, intermediate -pressure-turbine, high-points

Procedia PDF Downloads 37

Authors: Juliana Shimara Pires Ferrão, Letícia Palmeira Pinto, Francisco Palma Rennó, Francisco Javier Hernandez Blazquez

Abstract:

The ruminant stomach is a complex and multi-chambered organ. Although the true stomach (abomasum) is fully differentiated and functional at birth, the same does not occur with the rumen chamber. At this moment, rumen papillae are small or nonexistent. The papillae only fully develop after weaning and during calf growth. Papillae development and ruminal epithelium specialization during the fetus growth and at birth must be two interdependent processes that will prepare the rumen to adapt to ruminant adult feeding. The microscopic study of rumen epithelium at these early phases of life is important to understand how this structure prepares the rumen to deal with the following weaning processes and its functional activation. Samples of ruminal mucosa of bovine fetuses (110- and 150 day-old) and newborn calves were collected (dorsal and ventral portions) and processed for light and electron microscopy and immunohistochemistry. The basal cell layer of the stratified pavimentous epithelium present in different ruminal portions of the fetuses was thicker than the same portions of newborn calves. The superficial and intermediate epithelial layers of 150 day-old fetuses were thicker than those found in the other 2 studied ages. At this age (150 days), dermal papillae begin to invade the intermediate epithelial layer which gradually disappears in newborn calves. At birth, the ruminal papillae project from the epithelial surface, probably by regression of the epithelial cells (transitory cells) surrounding the dermal papillae. The PCNA cell proliferation index (%) was calculated for all epithelial samples. Fetuses 150 day-old showed increased cell proliferation in basal cell layer (Dorsal Portion: 84.2%; Ventral Portion: 89.8%) compared to other ages studied. Newborn calves showed an intermediate index (Dorsal Portion: 65.1%; Ventral Portion: 48.9%), whereas 110 day-old fetuses had the lowest proliferation index (Dorsal Portion: 57.2%; Ventral Portion: 20.6%). Regarding the transitory epithelium, 110 day-old fetuses showed the lowest proliferation index (Dorsal Portion: 44.6%; Ventral Portion: 20.1%), 150 day-old fetuses showed an intermediate proliferation index (Dorsal Portion: 57.5%; Ventral Portion: 71.1%) and newborn calves presented a higher proliferation index (Dorsal Portion: 75.1%; Ventral Portion: 19.6%). Under TEM, the 110- and 150 day-old fetuses presented thicker and poorly organized basal cell layer, with large nuclei and dense cytoplasm. In newborn calves, the basal cell layer was more organized and with fewer layers, but typically similar in both regions of the rumen. For the transitory epithelium, fetuses displayed larger cells than those found in newborn calves with less electrondense cytoplasm than that found in the basal cells. The ruminal dorsal portion has an overall higher cell proliferation rate than the ventral portion. Thus we can infer that the dorsal portion may have a higher cell activity than the ventral portion during ruminal development. Moreover, the basal cell layer is thicker in the 110- and 150 day-old fetuses than in the newborn calves. The transitory epithelium, which is much reduced, at birth may have a structural support function of the developing dermal papillae. When it regresses or is sheared off, the papillae are “carved out” from the surrounding epithelial layer.

Keywords: bovine, calf, epithelium, fetus, hematoxylin-eosin, immunohistochemistry, TEM, Rumen

Procedia PDF Downloads 358

Authors: Mohammad J. Rezai, Fereshteh Davarpanah

Abstract:

Producing a text in a language which is not one’s mother tongue can be a demanding task for language learners. Examining lexical errors committed by EFL learners is a challenging area of investigation which can shed light on the process of second language acquisition. Despite the considerable number of investigations into grammatical errors, few studies have tackled formal and semantic errors of lexis committed by EFL learners. The current study aimed at examining Persian learners’ formal and semantic errors of lexis in English. To this end, 60 students at three different proficiency levels were asked to write on 10 different topics in 10 separate sessions. Finally, 600 essays written by Persian EFL learners were collected, acting as the corpus of the study. An error taxonomy comprising formal and semantic errors was selected to analyze the corpus. The formal category covered misselection and misformation errors, while the semantic errors were classified into lexical, collocational and lexicogrammatical categories. Each category was further classified into subcategories depending on the identified errors. The results showed that there were 2583 errors in the corpus of 9600 words, among which, 2030 formal errors and 553 semantic errors were identified. The most frequent errors in the corpus included formal error commitment (78.6%), which were more prevalent at the advanced level (42.4%). The semantic errors (21.4%) were more frequent at the low intermediate level (40.5%). Among formal errors of lexis, the highest number of errors was devoted to misformation errors (98%), while misselection errors constituted 2% of the errors. Additionally, no significant differences were observed among the three semantic error subcategories, namely collocational, lexical choice and lexicogrammatical. The results of the study can shed light on the challenges faced by EFL learners in the second language acquisition process.

Keywords: collocational errors, lexical errors, Persian EFL learners, semantic errors

Procedia PDF Downloads 120

Authors: Mohammad Hadi Mahmoodi, Elahe Saedpanah

Abstract:

Since pronunciation is among those factors that can have strong effects on EFL learners’ successful communication, instructional programs with accurate pronunciation purposes seem to be a necessity in any L2 teaching context. The widespread use of smart mobile phones brings with itself various educational applications, which can assist foreign language learners in learning and speaking another language other than their L1. In line with this supportive innovation, the present study investigated the role of LDOCE (Longman Dictionary of Contemporary English), a mobile application, on improving Iranian EFL learners’ pronunciation accuracy. To this aim, 40 EFL learners studying English at the intermediate level participated in the current study. This was an experimental research with two groups of 20 students in an experimental and a control group. The data were collected through the administration of a pronunciation pretest before the instruction and a post-test after the treatment. In addition, the assessment was based on the pupils’ recorded voices while reading the selected words. The results of the independent samples t-test indicated that using LDOCE significantly affected Iranian EFL learners' pronunciation accuracy with those in the experimental group outperforming their control group counterparts.

Keywords: LDOCE, EFL learners, pronunciation accuracy, CALL, MALL

Procedia PDF Downloads 526

Authors: M. Irannezhad, E. H. N. Gashti, U. Moback, B. Kløve

Abstract:

Climate change because of increases in concentration level of greenhouse gases emissions to the atmosphere will result in mean sea level rise about +1 m by 2100. To prevent coastal floods resulted from the sea level rising, different flood control structures have been built, e.g. the Thames barrier on the Thames River in London (UK), with acceptable protection levels at least so far. Gothenburg located on the southwest coast of Sweden, with the River Göta älv running through it, is one of vulnerable cities to the accelerated rises in mean sea level. Developing a water level model by MATLAB, we evaluated using a sea barrage in the Göta älv River as the flood control structure for protecting the Gothenburg city during this century. Considering three operational scenarios for two barriers in upstream and downstream, the highest sea level was estimated to + 2.95 m above the current mean sea level by 2100. To verify flood protection against such high sea levels, both barriers have to be closed. To prevent high water level in the River Göta älv reservoir, the barriers would be open when the sea level is low. The suggested flood control structures would successfully protect the city from flooding events during this century.

Keywords: climate change, flood control structures, gothenburg, sea level rising, water level mode

Procedia PDF Downloads 333

Authors: Siamak Jamshidi

Abstract:

The Caspian Sea is the Earth's largest inland body of water. One of the most important issues related to the sea is water level changes. For measuring and recording Caspian Sea water level, there are at least three gauges and radar equipment in Anzali, Nowshahr and Amirabad Ports along the southern boundary of the Caspian Sea. It seems that evaporation, hotter surface air temperature, and in general climate change is the main reasons for its water level fluctuations. Gorgan Bay in the eastern part of the southern boundary of the Caspian Sea is one of the areas under the effect of water level fluctuation. Based on the results of field measurements near the Gorgan Bay mouth temperature ranged between 24°C–28°C and salinity was about 13.5 PSU in midsummer while temperature changed between 10-11.5°C and salinity mostly was 15-16.5 PSU in mid-winter. The decrease of Caspian Sea water level and rivers outflow are the two most important factors for the increase in water salinity of the Gorgan Bay. Results of field observations showed that, due to atmospheric factors, climate changes and decreasing of precipitation over the southern basin of the Caspian Sea during last decades, the water level of bay was reduced around 0.5 m.

Keywords: Caspian Sea, Gorgan Bay, water level fluctuation, climate changes

Procedia PDF Downloads 152

Authors: H. I. Obadiah, S. N. Wieser, E. A. Omudu, B. O. Atu, O. Byanet, L. Schnittger, M. Florin-Christensen

Abstract:

Sarcocystis sp. are Apicomplexan protozoan parasites with a life cycle that involves a predator and a prey as final and intermediate hosts, respectively. In tissues of the intermediate hosts, the parasites produce sarcocysts that vary in size and morphology according to the species. When a suitable predator ingests sarcocyst-containing meat, the parasites are released in the intestine and undergo sexual reproduction producing infective sporocysts, which are excreted with the feces into the environment. The cycle is closed when a prey ingests sporocyst-contaminated water or pasture; the parasites gain access to the circulation, and eventually invade tissues and reproduce asexually yielding sarcocysts. Pig farming is a common practice in Nigeria as well as in many countries around the world. In addition to its importance as protein source, pork is also a source of several pathogens relevant to humans. In the case of Sarcocystis, three species have been described both in domestic and wild pigs, namely, S. miescheriana, S. porcifelis and S. suihominis. Humans can act both as final and aberrant intermediate hosts of S. suihominis, after ingesting undercooked sarcocyst-infested pork. Infections are usually asymptomatic but can be associated with inappetence, nausea, vomiting and diarrhea, or with muscle pain, fever, eosinophilia and bronchospasm, in humans acting as final or intermediate hosts, respectively. Moreover, excretion of infective forms with human feces leads to further dissemination of the infection. In this study, macroscopic sarcocysts of white color, oval shape and a size range of approximately 3-5 mm were observed in the skeletal muscle of a slaughtered pig in an abattoir in Makurdi, Benue State, Nigeria, destined to human consumption. Sarcocysts were excised and washed in distilled water, and genomic DNA was extracted using a commercial kit. The near-complete length of the 18S rRNA gene was analyzed after PCR amplification of two overlapping fragments, each of which were submitted to direct sequencing. In addition, the mitochondrial cytochrome oxidase (cox-1) gene was PCR-amplified and directly sequenced. Two phylogenetic trees containing the obtained sequences along with available relevant 18S rRNA and cox-1 sequences were constructed by neighbor joining after alignment, using the corresponding sequences of Toxoplasma gondii as outgroup. The results showed in both cases that the analyzed sequences grouped with S. suihominis with high bootstrap value, confirming the identity of this macroscopic sarcocyst-forming parasite as S. suihominis. To the best of our knowledge, these results represent the first demonstration of this parasite in pigs of Nigeria and the largest sarcocysts described so far for S. suihominis. The close proximity between pigs and humans in pig farms, and the frequent poor sanitary conditions in human dwellings strongly suggest that the parasite undergoes the sexual stages of its life cycle in humans as final hosts. These findings provide an important reference for the examination and control of Sarcocystis species in pigs of Nigeria.

Keywords: nigeria, pork, sarcocystis suihominis, zoonotic parasite

Procedia PDF Downloads 66

Authors: Mark Jason E. Arca, Jay Vee R. Linatoc, Rex Francis N. Lupango, Michael Joe A. Ramirez

Abstract:

Participation promises an avenue for citizens to take part in governance, but it does not necessarily mean effective participation. The proper integration of participants in the decision-making process should be properly addressed to ensure effectiveness. This study explores the integration of the participants in the decision-making process to reveal the level of participation in the Solid Waste Management audit done by the Citizen Participatory Audit (CPA), a program under the supervision of the Commission on Audit. Specifically, this study will use the experience of participation to identify emerging themes that will help reveal the level of participation through the integrated ladder of participation. The researchers used key informant interviews to gather necessary data from the actors of the program. The findings revealed that the level of participation present in the CPA is at the Placation level, a level below the program’s targeted level of participation. The study also allowed the researchers to reveal facilitating factors in the program that contributed to a better understanding of the practice of participation.

Keywords: citizen participation, culture of participation, ladder of participation, level of participation

Procedia PDF Downloads 383

Authors: Li Lin Ong, Duc Thinh Khong, Zaher M. A. Judeh

Abstract:

Phenylpropanoid sucrose esters (PSEs) are natural compounds found in various medicinal plants which exhibit important biological activities such as antiproliferation and α- and β-glucosidase inhibitory activities. Despite their potential as new therapeutics, total synthesis of PSEs has been very limited as their inherent structures contain one or more (substituted) cinnamoyl groups randomly allocated on the sucrose core via ester linkage. Since direct acylation of unprotected sucrose would be complex and tedious due to the presence of eight free hydroxyl groups, partially protected 2,1’:4,6-di-O-diisopropylidene sucrose was used as the starting material instead. However, similar reactivity between the remaining four hydroxyl groups still pose a challenge in the total synthesis of PSEs as the lack of selectivity can restrict customisation where acylation at specific OH is desired. To overcome this problem, a 4-step orthogonal protection scheme was developed. In this scheme, the remaining four hydroxyl groups on 2,1’:4,6-di-O-diisopropylidene sucrose, 6’-OH, 3’-OH, 4’-OH, and 3-OH, were protected with different protecting groups with an overall yield of > 40%. This orthogonally protected intermediate would provide a convenient and divergent access to a wider range of natural and synthetic PSEs as (substituted) cinnamoyl groups can be selectively introduced at desired positions. Using this scheme, three different series of monosubstituted PSEs were successfully synthesized where (substituted) cinnamoyl groups were introduced selectively at O-3, O-3’, and O-4’ positions, respectively. The expanded library of PSEs would aid in structural-activity relationship study of PSEs for identifying key components responsible for their biological activities.

Keywords: orthogonal protection, phenylpropanoid sucrose esters, selectivity, sucrose

Procedia PDF Downloads 138