Search results for: fundamental frequency of soil stratum

Authors: A. Yanik, U. Aldemir

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This study investigates the benefits of implementing the semi-active devices in relation to passive viscous damping in the context of seismically isolated bridge structures. Since the intrinsically nonlinear nature of semi-active devices prevents the direct evaluation of Laplace transforms, frequency response functions are compiled from the computed time history response to sinusoidal and pulse-like seismic excitation. A simple semi-active control policy is used in regard to passive linear viscous damping and an optimal non-causal semi-active control strategy. The control strategy requires optimization. Euler-Lagrange equations are solved numerically during this procedure. The optimal closed-loop performance is evaluated for an idealized controllable dash-pot. A simplified single-degree-of-freedom model of an isolated bridge is used as numerical example. Two bridge cases are investigated. These cases are; bridge deck without the isolation bearing and bridge deck with the isolation bearing. To compare the performances of the passive and semi-active control cases, frequency dependent acceleration, velocity and displacement response transmissibility ratios T_a(w), T_v(w), and T_d(w) are defined. To fully investigate the behavior of the structure subjected to the sinusoidal and pulse type excitations, different damping levels are considered. Numerical results showed that, under the effect of external excitation, bridge deck with semi-active control showed better structural performance than the passive bridge deck case.

Keywords: bridge structures, passive control, seismic, semi-active control, viscous damping

Procedia PDF Downloads 242

Authors: Rachel Ashwell, Sally Millett

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Introduction: Adequate post-operative pain relief is a key priority in the delivery of caesarean sections. This improves patient experience, reduces morbidity and enables optimal mother-infant interaction. Recommendations outlined in the NICE guidelines for caesarean section (CS) include offering peri-operative intrathecal/epidural diamorphine and post-operative opioid analgesics; offering non-steroidal anti-inflammatory drugs (NSAIDs) unless contraindicated and taking hourly observations for 12 hours following intrathecal diamorphine. Method: This audit assessed the provision of post-CS analgesia in 29 women over a two-week period. Indicators used were the use of intrathecal/epidural opioids, use of post-operative opioids and NSAIDs, frequency of observations and patient satisfaction with pain management on post-operative days 1 and 2. Results: All women received intrathecal/epidural diamorphine, 97% were prescribed post-operative opioids and all were prescribed NSAIDs unless contraindicated. Hourly observations were not maintained for 12 hours following intrathecal diamorphine. 97% of women were satisfied with their pain management on post-operative day 1 whereas only 75% were satisfied on day 2. Discussion: This service meets the proposed standards for the provision of post-operative analgesia, achieving high levels of patient satisfaction 1 day after CS. However, patient satisfaction levels are significantly lower on post-operative day 2, which may be due to reduced frequency of observations. The lack of an official audit standard for patient satisfaction on postoperative day 2 may result in reduced incentive to prioritise pain management at this stage.

Keywords: Caesarean section, analgesia, postoperative care, patient satisfaction

Procedia PDF Downloads 387

Authors: Azadeh Mottaghi, Reyhaneh Yousefi, Saeed Safari

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Background: Bariatric surgery is widely proposed as the most effective approach to mitigate the growing pace of morbid obesity. As bariatric surgery candidates suffer from pre-existing nutritional deficiencies, it is of great importance to assess nutritional status of candidates before surgery in order to establish appropriate nutritional interventions. Objectives: The present study assessed and represented baseline data according to the nutritional status among candidates for bariatric surgery. Methods: A cross-sectional analysis of pre-surgery data was collected on 170 morbidly obese patients undergoing bariatric surgery between October 2017 and February 2018. Dietary intake data (evaluated through 147-item food frequency questionnaire), anthropometric measures and biochemical parameters were assessed. Results: Participants included 145 females (25 males) with average age of 37.3 ± 10.2 years, BMI of 45.7 ± 6.4 kg/m² and reported to have a total of 72.3 ± 22.2 kg excess body weight. The most common nutritional deficiencies referred to iron, ferritin, transferrin, albumin, vitamin B12, and vitamin D, the prevalence of which in the study population were as followed; 6.5, 6.5, 3, 2, 17.6 and 66%, respectively. Mean energy, protein, fat, and carbohydrate intake were 3887.3 ± 1748.32 kcal/day, 121.6 ± 57.1, 144.1 ± 83.05, and 552.4 ± 240.5 gr/day, respectively. The study population consumed lower levels of iron, calcium, folic acid, and vitamin B12 compared to the Dietary Reference Intake (DRI) recommendations (2, 26, 2.5, and 13%, respectively). Conclusion: According to the poor dietary quality of bariatric surgery candidates, leading to nutritional deficiencies pre-operatively, close monitoring and tailored supplementation pre- and post-bariatric surgery are required.

Keywords: bariatric surgery, food frequency questionnaire, obesity, nutritional status

Procedia PDF Downloads 172

Authors: Rammah Abdlbagi, Similoluwa Biyi, Aakash Pai

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Introduction: Short-term ureteric stents are commonly placed after ureteroscopy procedures. The removal usually entails having a flexible cystoscopy, which entails a further invasive procedure. There are often delays in removing the stent as departments have limited cystoscopy availability. However, if stents with extraction strings are used, the patient or a clinician can remove them. The aim of the study is to assess the safety and effectiveness of the use of a stent with a string. Method: A retrospective, single-institution study was conducted over a three-month period. Twenty consecutive patients had ureteric stents with string insertion. Ten of the patients had a stent removal procedure previously with flexible cystoscopy. A validated questionnaire was used to assess outcomes. Primary outcomes included: dysuria, hematuria, urinary frequency, and disturbance of the patient’s daily activities. Secondary outcomes included pain experience during the stent removal. Result: Fifteen patients (75%) experienced hematuria and frequency. Two patients experienced pain and discomfort during the stent removal (10%). Two patients had experienced a disturbance in their daily activity (10%). All patients who had stent removal before using flexible cystoscopy preferred the removal of the stent using a string. None of the patients had stent displacement. The median stent dwell time was five days. Conclusion: Patient reported outcomes measures for the indwelling period of a stent with extraction string are equivalent to the published data on stents. Extraction strings mean that the stent dwell time can be reduced. The removal of the stent on extraction strings is more tolerable than the conventional stent.

Keywords: ureteric stent, string flexible cystoscopy, stent symptoms, validated questionnaire

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Authors: Nada Al-Qallaf, Aisha Al-Barood, Djamel Lekmine, Srinivasan Vedhapuri

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Kuwait Oil Company (KOC) under the supervision of Kuwait National Focal Point (KNFP) is planning to remediate 26 million (M) m3 of oil-contaminated soil in oil fields of Kuwait as a direct and indirect fallout of the Gulf War during 1990-1991. This project is funded by the United Nations Compensation Commission (UNCC) under the Kuwait Environmental Remediation Program (KERP). Oil-contamination of the soil occurred due to the destruction of the oil wells and spilled crude oil across the land surface and created ‘oil lakes’ in low lying land. Aerial fall-out from oil spray and combustion products from oil fires combined with the sand and gravel on the ground surface to form a layer of hardened ‘Tarcrete’. The unique fresh groundwater lenses present in the Raudhatain and Sabriya subsurface areas had been impacted by the discharge and/or spills of dissolved petroleum constituents. These fresh groundwater aquifers were used for drinking water purposes until 1990, prior to invasion. This has significantly damages altered the landscape, ecology and habitat of the flora and fauna and in Kuwait Desert. Under KERP, KOC is fully responsible for the planning and execution of the remediation and restoration projects in KOC oil fields. After the initial recommendation of UNCC to construct engineered landfills for containment and disposal of heavily contaminated soils, two landfills were constructed, one in North Kuwait and another in South East Kuwait of capacity 1.7 million m3 and 0.5 million m3 respectively. KOC further developed the Total Remediation Strategy in conjunction with KNFP and has obtained UNCC approval. The TRS comprises of elements such as Risk Based Approach (RBA), Bioremediation of low Contaminated Soil levels, Remediation Treatment Technologies, Sludge Disposal via Beneficial Recycling or Re-use and Engineered landfills for Containment of untreatable materials. Risk Based Assessment as a key component to avoid any unnecessary remedial works, where it can be demonstrated that human health and the environment are sufficiently protected in the absence of active remediation. This study demonstrates on the risks of tarcrete materials spread over areas 20 Km2 on the fresh Ground water lenses/catchment located beneath the Sabriyah and Raudhatain oil fields in North Kuwait. KOC’s primary objective is to provide justification of using RBA, to support a case with the Kuwait regulators to leave the tarcrete material in place, rather than seek to undertake large-scale removal and remediation. The large-scale coverage of the tarcrete in the oil fields and perception that the residual contamination associated with this source is present in an environmentally sensitive area essentially in ground water resource. As part of this assessment, conceptual site model (CSM) and complete risk-based and fate and transport modelling was carried out which includes derivation of site-specific assessment criteria (SSAC) and quantification of risk to identified waters resource receptors posed by tarcrete impacted areas. The outcome of this assessment was determined that the residual tarcrete deposits across the site area shall not create risks to fresh groundwater resources and the remedial action to remove and remediate the surficial tarcrete deposits is not warranted.

Keywords: conceptual site model, fresh groundwater, oil-contaminated soil, tarcrete, risk based assessment

Procedia PDF Downloads 174

Authors: Jacqueline M. Dias, Amina A Khowaja

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Clinical education is one of the most important components of a nursing curriculum as it develops the students’ cognitive, psychomotor and affective skills. Clinical teaching ensures the integration of knowledge into practice. As the numbers of students increase in the field of nursing coupled with the faculty shortage, clinical preceptors are the best choice to ensure student learning in the clinical settings. The clinical preceptor role has been introduced in the undergraduate nursing programme. In Pakistan, this role emerged due to a faculty shortage. Initially, two clinical preceptors were hired. This study will explore clinical preceptors views and experiences of precepting Bachelor of Science in Nursing (BScN) students in an undergraduate program. A case study design was used. As case studies explore a single unit of study such as a person or very small number of subjects; the two clinical preceptors were fundamental to the study and served as a single case. Qualitative data were obtained through an iterative process using in depth interviews and written accounts from reflective journals that were kept by the clinical preceptors. The findings revealed that the clinical preceptors were dedicated to their roles and responsibilities. Another, key finding was that clinical preceptors’ prior knowledge and clinical experience were valuable assets to perform their role effectively. The clinical preceptors found their new role innovative and challenging; it was stressful at the same time. Findings also revealed that in the clinical agencies there were unclear expectations and role ambiguity. Furthermore, clinical preceptors had difficulty integrating theory into practice in the clinical area and they had difficulty in giving feedback to the students. Although this study is localized to one university, generalizations can be drawn from the results. The key findings indicate that the role of a clinical preceptor is demanding and stressful. Clinical preceptors need preparation prior to precepting students on clinicals. Also, institutional support is fundamental for their acceptance. This paper focuses on the views and experiences of clinical preceptors undertaking a newly established role and resonates with the literature. The following recommendations are drawn to strengthen the role of the clinical preceptors: A structured program for clinical preceptors is needed along with mentorship. Clinical preceptors should be provided with formal training in teaching and learning with emphasis on clinical teaching and giving feedback to students. Additionally, for improving integration of theory into practice, clinical modules should be provided ahead of the clinical. In spite of all the challenges, ten more clinical preceptors have been hired as the faculty shortage continues to persist.

Keywords: baccalaureate nursing education, clinical education, clinical preceptors, nursing curriculum

Procedia PDF Downloads 174

Authors: Ratneev Kaur, Tajinder Kaur, Anupam Kaur

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Introduction: Polycystic Ovary Syndrome (PCOS) is a heterogenous disorder of endocrine system among women of reproductive age. PCOS is characterized by hyperandrogenism, anovulation, polycystic ovaries, hirsutism, obesity, and hyperinsulinemia. Several pathways are implicated in its etiology including the metabolic pathway of steroid hormone synthesis regulatory pathways. PCOS is an androgen excess disorder, genes operating in steroidogenesis may alter pathogenesis of PCOS. The cytochrome P450scc is a cholesterol side chain cleavage enzyme coded by CYP11A1 gene and catalyzes conversion of cholesterol to pregnenolone, the initial and rate-limiting step in steroid hormone synthesis. It is postulated that polymorphisms in this gene may play an important role in the regulation of CYP11A1 expression and leading to increased or decreased androgen production. The present study will be the first study from north India to best of our knowledge, to analyse the association of CYP11A1 (rs11632698) polymorphism in women suffering from PCOS. Methodology: The present study was approved by ethical committee of Guru Nanak Dev University in consistent with declaration of Helsinki. A total of 300 samples (150 PCOS cases and 150 controls) were recruited from Hartej hospital, for the present study. Venous blood sample (3ml) was withdrawn from women diagnosed with PCOS by doctor, according to Rotterdam 2003 criteria and from healthy age matched controls only after informed consent and detailed filled proforma. For molecular genetics analysis, blood was stored in EDTA vials. After DNA isolation by organic method, PCR-RFLP approach was used for genotyping and association analysis of rs11632698 polymorphism. Statistical analysis was done to check for significance of selected polymorphism with PCOS. Results: In 150 PCOS cases, the frequency of AA, AG and GG genotype was found to be 48%, 35%, and 13% compared to 62%, 27% and 8% in 150 controls. The major allele (A) and minor allele (G) frequency was 68% and 32% in cases and 78% and 22% in controls. Minor allele frequency was higher in cases as compared to controls, as well as the distribution of genotype was observed to be statistically significant (ᵡ²=6.525, p=0.038). Odds ratio in dominant, co-dominant and recessive models observed was 1.81 (p=0.013), 1.54 (p=0.012) and 1.77 (p=0.132) respectively. Conclusion: The present study showed statistically significant association of rs11632698 with PCOS (p=0.038) in North Indian women.

Keywords: polycystic ovary syndrome, CYP11A1, rs11632698, hyperandrogenism

Procedia PDF Downloads 143

Authors: Babatunde Olatujoye, Binbin Yang

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Microwave imaging is a portable, noninvasive, and non-ionizing imaging technique that employs low-power microwave signals to reveal objects in the microwave frequency range. This technique has immense potential for adoption in commercial and scientific applications such as security scanning, material characterization, and nondestructive testing. This work presents a monostatic microwave imaging setup using an Ultra-Wideband (UWB), low-cost, miniaturized Vivaldi antenna with a bandwidth of 1 – 6 GHz. The backscattered signals (S-parameters) of the Vivaldi antenna used for scanning targets were measured in the lab using a VNA. An automated two-dimensional (2-D) scanner was employed for the 2-D movement of the transceiver to collect the measured scattering data from different positions. The targets consist of four metallic objects, each with a distinct shape. Similar setup was also simulated in Ansys HFSS. A high-resolution Back Propagation Algorithm (BPA) was applied to both the simulated and experimental backscattered signals. The BPA utilizes the phase and amplitude information recorded over a two-dimensional aperture of 50 cm × 50 cm with a discreet step size of 2 cm to reconstruct a focused image of the targets. The adoption of BPA was demonstrated by coherently resolving and reconstructing reflection signals from conventional time-of-flight profiles. For both the simulation and experimental data, BPA accurately reconstructed a high resolution 2D image of the targets in terms of shape and location. An improvement of the BPA, in terms of target resolution, was achieved by applying the filtering method in frequency domain.

Keywords: back propagation, microwave imaging, monostatic, vivialdi antenna, ultra wideband

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Authors: Doaa M. Elghannam, Nashwa Khayrat Abousamra, Doaa A. Shahin, Enas F. Goda, Hanan Azzam, Emad Azmy, Manal Salah El-Din

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Background: The pathogenesis of acute myeloid leukemia (AML) involves the cooperation of mutations promoting proliferation/survival and those impairing differentiation. Point mutations of the NRAS gene are the most frequent somatic mutations causing aberrant signal-transduction in acute myeloid leukemia (AML). Aim: The present work was conducted to study the frequency and prognostic significance of NRAS gene mutations (NRASmut) in de novo Egyptian adult AML. Material and methods: Bone marrow specimens from 150 patients with de novo acute myeloid leukemia and controls were analyzed by genomic PCR-SSCP at codons 12, 13 (exon 1), and 61 (exon 2) for NRAS mutations. Results: NRAS gene mutations was found in 19/150 (12.7%) AML cases, represented more frequently in the FAB subtype M4eo (P = 0.028), and at codon 12, 13 (14of 19; 73.7%). Patients with NRASmut had a significant lower peripheral marrow blasts (P = 0.004, P=0.03) and non significant improved clinical outcome than patients without the mutation. Complete remission rate was (63.2% vs 56.5%; p=0.46), resistant disease (15.8% vs 23.6%; p=0.51), three years overall survival (44% vs 42%; P = 0.85) and disease free survival (42.1% vs 38.9%, P = 0.74). Multivariate analysis showed that age was the strongest unfavorable factor for overall survival (relative risk [RR], 1.9; P = .002), followed by cytogenetics (P = .004). FAB types, NRAS mutation, and leukocytosis were less important. Conclusions: NRAS gene mutation frequency and spectrum differ between biologically distinct subtypes of AML but do not significantly influence prognosis and clinical outcome.

Keywords: NRAS Gene, egyptian adult, acute myeloid leukemia, cytogenetics

Procedia PDF Downloads 99

Authors: Zhuanfang Fred Zhang, Tim C. Johnson, Yilin Fang, Chris E. Strickland

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A variety of geophysical techniques are available to image the opaque subsurface with little or no contact with the soil. It is common to conduct time-lapse surveys of different types for a given site for improved results of subsurface imaging. Regardless of the chosen survey methods, it is often a challenge to process the massive amount of survey data. The currently available software applications are generally based on the one-dimensional assumption for a desktop personal computer. Hence, they are usually incapable of imaging the three-dimensional (3D) processes/variables in the subsurface of reasonable spatial scales; the maximum amount of data that can be inverted simultaneously is often very small due to the capability limitation of personal computers. Presently, high-performance or integrating software that enables real-time integration of multi-process geophysical methods is needed. E4D-MP enables the integration and inversion of time-lapsed large-scale data surveys from geophysical methods. Using the supercomputing capability and parallel computation algorithm, E4D-MP is capable of processing data across vast spatiotemporal scales and in near real time. The main code and the modules of E4D-MP for inverting individual or combined data sets of time-lapse 3D electrical resistivity, spectral induced polarization, and gravity surveys have been developed and demonstrated for sub-surface imaging. E4D-MP provides capability of imaging the processes (e.g., liquid or gas flow, solute transport, cavity development) and subsurface properties (e.g., rock/soil density, conductivity) critical for successful control of environmental engineering related efforts such as environmental remediation, carbon sequestration, geothermal exploration, and mine land reclamation, among others.

Keywords: gravity survey, high-performance computing, sub-surface monitoring, electrical resistivity tomography

Procedia PDF Downloads 157

Authors: Mahmoud Roushdy, Mohamed El Naggar, Ahmed Yehia Abdelaziz

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Anchored sheet pile has been used worldwide as front quay walls for decades. With the increase in vessel drafts and weights, those sheet pile walls need to be upgraded by increasing the depth of the dredging line in front of the wall. A system has recently been used to increase the depth in front of the wall by installing a separated platform supported on a deep foundation (so called Relieving Platform) behind the sheet pile wall. The platform is structurally separated from the front wall. This paper presents a numerical investigation utilizing finite element analysis on the behavior of separated relieve platforms installed within existing anchored sheet pile quay walls. The investigation was done in two steps: a verification step followed by a parametric study. In the verification step, the numerical model was verified based on field measurements performed by others. The validated model was extended within the parametric study to a series of models with different backfill soils, separation gap width, and number of pile rows supporting the platform. The results of the numerical investigation show that using stiff clay as backfill soil (neglecting consolidation) gives better performance for the front wall and the first pile row adjacent to sandy backfills. The degree of compaction of the sandy backfill slightly increases lateral deformations but reduces bending moment acting on pile rows, while the effect is minor on the front wall. In addition, the increase in the separation gap width gradually increases bending moments on the front wall regardless of the backfill soil type, while this effect is reversed on pile rows (gradually decrease). Finally, the paper studies the possibility of reducing the number of pile rows along with the separation to take advantage of the positive separation effect on piles.

Keywords: anchored sheet pile, relieving platform, separation gap, upgrade quay wall

Procedia PDF Downloads 85

Authors: Sudson Sirivaidyapong, Ratthanan Sathienbumrungkit, Nongnapas Ruangpet, Nattanun Uaprayoon, Chawisa Wejjakul

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Many factors initiate mammary gland tumor in female dogs such as age, breed, sex, estrous cycle, birth control and pseudopregnancy. Those factors are mostly associated with canine sex hormone. In this study, questionnaires and direct interviews were used to collect information from owners of female dogs that had been diagnosed as mammary tumors at our veterinary teaching hospital, during January 2015 to October 2016 to compare the prevalence of mammary tumor between nulliparous and multiparous female dogs. 200 dogs (from all 212 mammary tumor patients, some were excluded because of inadequate information) were included in the study, 72.5% were nulliparous and 27.5% were multiparous. The results revealed that breed, age, birth control age and birth control methods were not different in both groups; most dogs in both groups were various purebreds, geriatric age, and low incidence of hormonal contraception while 100% of multiparous dogs and 83.7% of nulliparous dogs had been neutered at over two years old. The significant differences between two groups were the frequency of pseudopregnancy and estrus which were much higher in nulliparous female dogs. It can be concluded from our study that nulliparous dogs may be more likely at higher risk of mammary tumor compared to multiparous dogs from various factors especially, the frequency of estrus and the occurrence of pseudopregnancy which related to more times of sex hormonal contact. This study was a preliminary data for further studies to determine the other risk factors of mammary gland tumors in dogs, and to our knowledge, it is the first report on a significantly higher prevalence of mammary tumor in nulliparous female dogs than that in multiparous dogs. This finding corresponds with the study of breast cancer in women but may be from different causes and factors due to the differences in estrous physiology.

Keywords: canine, female dogs, nulliparous, multiparous, mammary tumor, prevalence

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Authors: Vladyslav Povoroznyuk, Larysa Martynyuk, Iryna Syzonenko, Liliya Martynyuk

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Osteoporosis is one of the important problems in postmenopausal women due to an increased risk of sudden and unexpected fractures. This study is aimed to determine the connection between bone mineral density (BMD) and trabecular bone score (TBS) in Ukrainian women suffering from metabolic syndrome. Participating in the study, 566 menopausal women aged 50-79 year-old were examined and divided into two groups: Group A included 336 women with no obesity (BMI ≤ 29.9 kg/m²), and Group B – 230 women with metabolic syndrome (diagnosis according to IDF criteria, 2005). Dual-energy X-ray absorptiometry was used for measuring of lumbar spine (L1-L4), femoral neck, total body and forearm BMD and bone quality indexes (last according to Med-Imaps installation). Data were analyzed using Statistical Package 6.0. A significant increase of lumbar spine (L1-L4), femoral neck, total body and ultradistal radius BMD was found in women with metabolic syndrome compared to those without obesity (p < 0.001) both in their totality and in groups of 50-59 years, 60-69 years, and 70-79 years. TBS was significantly higher in non-obese women compared to metabolic syndrome patients of 50-59 years and in the general sample (p < 0.05). Analysis showed significant positive correlation between body mass index (BMI) and BMD at all levels. Significant negative correlation between BMI and TBS (L1-L4) was established. Despite the fact that BMD indexes were significantly higher in women with metabolic syndrome, the frequency of vertebral and non-vertebral fractures did not differ significantly in the groups of patients.

Keywords: bone mineral density, trabecular bone score, metabolic syndrome, fracture

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Authors: Boonyarat Chaleephay

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The purpose of this research paper was to describe the relationship of acupressure points on the anterior surface of the upper limb in accordance with Applied Thai Traditional Massage (ATTM) and the deep structures located at those acupressure points. There were 2 population groups; normal subjects and cadaver specimens. Eighteen males with age ranging from 20-40 years old and seventeen females with ages ranging from 30-97 years old were studies. This study was able to obtain a fundamental knowledge concerning acupressure point and the deep structures that related to those acupressure points. It might be used as the basic knowledge for clinically applying and planning treatment as well as teaching in ATTM.

Keywords: acupressure point (AP), applie Thai traditional medicine (ATTM), paresthesia, numbness

Procedia PDF Downloads 240

Authors: A. Majeed, M.K. Abbasi, S. Hameed, A. Imran, T. Naqqash, M. K. Hanif

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Plant growth-promoting rhizobacteria (PGPR) are free-living soil bacteria that aggressively colonize the rhizosphere/plant roots, and enhance the growth and yield of plants when applied to seed or crops. Root associated (endophytic and rhizospheric) PGPR were isolated from Sunflower (Helianthus anus) grown in soils collected from 16 different sites of sub division Dhirkot, Poonch, Azad Jammu & Kashmir, Pakistan. A total of 150 bacterial isolates were isolated, purified, screened in vitro for their plant growth promoting (PGP) characteristics. 11 most effective isolates were selected on the basis of biochemical assays (nitrogen fixation, phosphate solubilization, growth hormone production, biocontrol assay, and carbon substrates utilization assay through gas chromatography (GCMS), spectrophotometry, high performance liquid chromatography HPLC, fungal and bacterial dual plate assay and BIOLOG GN2/GP2 microplate assay respectively) and were tested on the crop under controlled and field conditions. From the inoculation assay, the most promising 4 strains (on the basis of increased root/shoot weight, root/shoot length, seed oil content, and seed yield) were than selected for colonization studies through confocal laser scanning and transmission electron microscope. 16Sr RNA gene analysis showed that these bacterial isolates belong to Pseudononas, Enterobacter, Azospirrilum, and Citobacter genera. This study is the clear evident that such isolates have the potential for application as inoculants adapted to poor soils and local crops to minimize the chemical fertilizers harmful for soil and environment

Keywords: PGPR, nitrogen fixation, phosphate solubilization, colonization

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Authors: Selva Georgena D., Videcoq Etienne, Caner Julien, Benselama Adel, Girault Manu

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A Two-Phase Thermosyphon Loop (TPTL) is a passive cooling system which does not require a pump to function. Therefore, TPTL is a simple and robust device and its physics is complex to describe because of the coupled phenomena: heat flux, nucleation, fluid dynamics and gravitational effects. Moreover, the dynamic behavior of TPTL shows some physical instabilities and the actual occurrence of such a behavior remains unknown. The aim of this study is to propose a thermal balance of the TPTL to better identify the fundamental reasons for the appearance of the instabilities.

Keywords: Two-phase flow, passive cooling system, thermal reliability, thermal experimental study, liquid-vapor phase change

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Authors: Jakub Czyżycki, Paweł Twardowski

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Thin-walled components made of aluminum alloys are increasingly found in many fields of industry, and they dominate the aerospace industry. The machining of thinwalled structures encounters many difficulties related to the high susceptibility of the workpiece, which causes vibrations including the most unfavorable ones called chatter. The effect of these phenomena is the difficulty in obtaining the required geometric dimensions and surface quality. The purpose of this study is to analyze vibrations arising during machining of thin-walled workpieces made of aluminum alloy EN AW-7075. Samples representing actual thin-walled workpieces were examined in a different range of dimensions characterizing thin-walled workpieces. The tests were carried out in HSM high-speed machining (cutting speed vc = 1400 m/min) using a monolithic solid carbide endmill. Measurement of vibration was realized using a singlecomponent piezoelectric accelerometer 4508C from Brüel&Kjær which was mounted directly on the sample before machining, the measurement was made in the normal feed direction AfN. In addition, the natural frequency of the tested thin-walled components was investigated using a laser vibrometer for an broader analysis of the tested samples. The effect of vibrations on machining accuracy was presented in the form of surface images taken with an optical measuring device from Alicona. A classification of the vibrations produced during the test was carried out, and were analyzed in both the time and frequency domains. Observed significant influence of the thickness of the thin-walled component on the course of vibrations during machining.

Keywords: high-speed machining, thin-walled elements, thin-walled components, milling, vibrations

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Authors: P. G. S. Madushani, L. D. Illeperuma

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Abstract Noise is one of the most common physical hazards in industrial settings. The prevalence of Noise Induced Hearing Loss (NIHL) is on the rise with increasedduration of exposure and the increase in the severity of hearing loss. The purpose of the study was to determine auditory effects among textile workers and to establish associations between the degree of hearing loss and exposure duration, degree of hearing loss and noise level and the proportion of hearing related complaints. A cross sectional descriptive study using purposive sampling was carried out. An interviewer administered questionnaire and Distortion Product Oto Acoustic Emission (DPOAE) hearing screening on 127 (72 female and 55 male) textile workers of the selected textile plant in Seeduwa, Sri Lanka was done (Age: M= 31.16, SD=7.75). Noise measurements were done in six sections of the factory and average noise levels were obtained. Diagnostic hearing evaluations were done for 60 (57.75%) subjects, referred from the DPOAE hearing screening test. The degree of hearing loss and the exposure duration had a significant association in the high frequency region of 4 kHz to 8 kHz (p < 0.05). Noise levels fluctuated between 90.3±0.8 dBA and 50.6. ±0.52 dBA. 30.83% of workers reported having NIHL. Most of the workers (33.9%) complained difficulty in conversing in noisy backgrounds. Other complaints as tinnitus, dizziness, ear fullness and headache were reported in less than 30%. workers who were exposed to noise for more than 15 years were affected with NIHL in the high frequency region. Administrative controls and engineering controls need to be implemented to manage hazardous noise levels in industrial settings. Hearing Conservation Programs should be initiated and implemented for textile workers.

Keywords: textile industry, NIHL, degree of hearing loss, noise levels, auditory effects

Procedia PDF Downloads 141

Authors: Shereif. H. Mahmoud

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Egypt has limited water resources, and it will be under water stress by the year 2030. Therefore, Egypt should consider natural and non-conventional water resources to overcome such a problem. Rain harvesting is one solution. This Paper presents a geographic information system (GIS) methodology - based on decision support system (DSS) that uses remote sensing data, filed survey, and GIS to identify potential RWH areas. The input into the DSS includes a map of rainfall surplus, slope, potential runoff coefficient (PRC), land cover/use, soil texture. In addition, the outputs are map showing potential sites for RWH. Identifying suitable RWH sites implemented in the ArcGIS model environment using the model builder of ArcGIS 10.1. Based on Analytical hierarchy process (AHP) analysis taking into account five layers, the spatial extents of RWH suitability areas identified using Multi-Criteria Evaluation (MCE). The suitability model generated a suitability map for RWH with four suitability classes, i.e. Excellent, Moderate, Poor, and unsuitable. The spatial distribution of the suitability map showed that the excellent suitable areas for RWH concentrated in the northern part of Egypt. According to their averages, 3.24% of the total area have excellent and good suitability for RWH, while 45.04 % and 51.48 % of the total area are moderate and unsuitable suitability, respectively. The majority of the areas with excellent suitability have slopes between 2 and 8% and with an intensively cultivated area. The major soil type in the excellent suitable area is loam and the rainfall range from 100 up to 200 mm. Validation of the used technique depends on comparing existing RWH structures locations with the generated suitability map using proximity analysis tool of ArcGIS 10.1. The result shows that most of exiting RWH structures categorized as successful.

Keywords: rainwater harvesting (RWH), geographic information system (GIS), analytical hierarchy process (AHP), multi-criteria evaluation (MCE), decision support system (DSS)

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Authors: Erwan Negre, Ewan J. O'Connor, Juha Toivonen

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The need for CO2 monitoring technologies grows simultaneously with the worldwide concerns regarding environmental challenges. To that purpose, we developed a compact coherent all-fiber ranged-resolved Differential Absorption Lidar (RR-DIAL). It has been designed along a tunable 2x1fiber optic switch set to a frequency of 1 Hz between two Distributed FeedBack (DFB) lasers emitting in the continuous-wave mode at 1571.41 nm (absorption line of CO2) and 1571.25 nm (CO2 absorption-free line), with linewidth and tuning range of respectively 1 MHz and 3 nm over operating wavelength. A three stages amplification through Erbium and Erbium-Ytterbium doped fibers coupled to a Radio Frequency (RF) driven Acousto-Optic Modulator (AOM) generates 100 ns pulses at a repetition rate from 10 to 30 kHz with a peak power up to 2.5 kW and a spatial resolution of 15 m, allowing fast and highly resolved CO2 profiles. The same afocal collection system is used for the output of the laser source and the backscattered light which is then directed to a circulator before being mixed with the local oscillator for heterodyne detection. Packaged in an easily transportable box which also includes a server and a Field Programmable Gate Array (FPGA) card for on-line data processing and storing, our setup allows an effective and quick deployment for versatile in-situ analysis, whether it be vertical atmospheric monitoring, large field mapping or sequestration site continuous oversight. Setup operation and results from initial field measurements will be discussed.

Keywords: CO2 profiles, coherent DIAL, in-situ atmospheric sensing, near infrared fiber source

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Authors: Sadi Ali, Yaser Kishawi

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As part of Palestine, Gaza Strip (365 km2 and 1.8 million habitants) is considered a semi-arid zone relies solely on the Coastal Aquifer. The coastal aquifer is only source of water with only 5-10% suitable for human use. This barely cover the domestic and agricultural needs of Gaza Strip. Palestinian Water Authority Strategy is to find non-conventional water resource from treated wastewater to irrigate 1500 hectares and serves over 100,000 inhabitants. A new WWTP project is to replace the old-overloaded Biet Lahia WWTP. The project consists of three parts; phase A (pressure line & 9 infiltration basins - IBs), phase B (a new WWTP) and phase C (Recovery and Reuse Scheme – RRS – to capture the spreading plume). Currently, phase A is functioning since Apr 2009. Since Apr 2009, a monitoring plan is conducted to monitor the infiltration rate (I.R.) of the 9 basins. Nearly 23 million m3 of partially treated wastewater were infiltrated up to Jun 2014. It is important to maintain an acceptable rate to allow the basins to handle the coming quantities (currently 10,000 m3 are pumped an infiltrated daily). The methodology applied was to review and analysis the collected data including the I.R.s, the WW quality and the drying-wetting schedule of the basins. One of the main findings is the relation between the Total Suspended Solids (TSS) at BLWWTP and the I.R. at the basins. Since April 2009, the basins scored an average I.R. of about 2.5 m/day. Since then the records showed a decreasing pattern of the average rate until it reached the lower value of 0.42 m/day in Jun 2013. This was accompanied with an increase of TSS (mg/L) concentration at the source reaching above 200 mg/L. The reducing of TSS concentration directly improved the I.R. (by cleaning the WW source ponds at Biet Lahia WWTP site). This was reflected in an improvement in I.R. in last 6 months from 0.42 m/day to 0.66 m/day then to nearly 1.0 m/day as the average of the last 3 months of 2013. The wetting-drying scheme of the basins was observed (3 days wetting and 7 days drying) besides the rainfall rates. Despite the difficulty to apply this scheme accurately a control of flow to each basin was applied to improve the I.R. The drying-wetting system affected the I.R. of individual basins, thus affected the overall system rate which was recorded and assessed. Also the ploughing activities at the infiltration basins as well were recommended at certain times to retain a certain infiltration level. This breaks the confined clogging layer which prevents the infiltration. It is recommended to maintain proper quality of WW infiltrated to ensure an acceptable performance of IBs. The continual maintenance of settling ponds at BLWWTP, continual ploughing of basins and applying soil treatment techniques at the IBs will improve the I.R.s. When the new WWTP functions a high standard effluent quality (TSS 20mg, BOD 20 mg/l and TN 15 mg/l) will be infiltrated, thus will enhance I.R.s of IBs due to lower organic load.

Keywords: SAT, wastewater quality, soil remediation, North Gaza

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Authors: Hui-Chen Tsai, Chien-Jen Ho, Bo-Wei Power Liang, Ying Shen, Yi-Hsin Lai

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Former Taiwan Metal Mining Corporation and its associated 3 wasted flue gas tunnels, hereinafter referred to as 'TMMC', was contaminated with heavy metals, Polychlorinated biphenyls (PCBs) and Total Petroleum Hydrocarbons (TPHs) in soil. Since the contamination had been exposed and unmanaged in the environment for more than 40 years, the extent of the contamination area is estimated to be more than 25 acres. Additionally, TMMC is located in a remote, mountainous area where almost no residents are residing in the 1-km radius area. Thus, it was deemed necessary to conduct an ecological risk assessment in order to evaluate the details of future contaminated site management plan. According to the winter and summer, ecological investigation results, one type of endangered, multiple vulnerable and near threaten plant was discovered, as well as numerous other protected species, such as Crested Serpent Eagle, Crested Goshawk, Black Kite, Brown Shrike, Taiwan Blue Magpie were observed. Ecological soil screening level (Eco-SSLs) developed by USEPA was adopted as a reference to conduct screening assessment. Since all the protected species observed surrounding TMMC site were birds, screening ecological risk assessment was conducted on birds only. The assessment was assessed mainly based on the chemical evaluation, which the contamination in different environmental media was compared directly with the ecological impact levels (EIL) of each evaluation endpoints and the respective hazard quotient (HQ) and hazard index (HI) could be obtained. The preliminary ecological risk assessment results indicated HI is greater than 1. In other words, the biological stressors (birds) were exposed to the contamination, which was already exceeded the dosage that could cause unacceptable impacts to the ecological system. This result was mainly due to the high concentration of arsenic, metal and lead; thus it was suggested the above mention contaminants should be remediated as soon as possible or proper risk management measures should be taken.

Keywords: screening, ecological risk assessment, ecological impact levels, risk management

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Authors: Naima Umar

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Mid-1960’s has been landmark in the history of Indian agriculture. It was in 1966-67 when a New Agricultural Strategy was put into practice to tide over chronic shortages of food grains in the country. This strategy adopted was the use High-Yielding Varieties (HYV) of seeds (wheat and rice), which was popularly known as the Green Revolution. This phase of agricultural development has saved us from hunger and starvation and made the peasants more confident than ever before, but it has also created a number of socio-economic and environmental implications such as the reduction in area under forest, salinization, waterlogging, soil erosion, lowering of underground water table, soil, water and air pollution, decline in soil fertility, silting of rivers and emergence of several diseases and health hazards. The state of Uttar Pradesh in the north is bounded by the country of Nepal, the states of Uttrakhand on the northwest, Haryana on the west, Rajasthan on the southwest, Madhya Pradesh on the south and southwest, and Bihar on the east. It is situated between 23052´N and 31028´N latitudes and 7703´ and 84039´E longitudes. It is the fifth largest state of the country in terms of area, and first in terms of population. Forming the part of Ganga plain the state is crossed by a number of rivers which originate from the snowy peaks of Himalayas. The fertile plain of the Ganga has led to a high concentration of population with high density and the dominance of agriculture as an economic activity. Present paper highlights the negative impact of new agricultural technology on health of the people and environment and will attempt to find out factors which are responsible for these implications. Karl Pearson’s Correlation coefficient technique has been applied by selecting 1 dependent variable (i.e. Productivity Index) and some independent variables which may impact crop productivity in the districts of the state. These variables have categorized as: X1 (Cropping Intensity), X2 (Net irrigated area), X3 (Canal Irrigated area), X4 (Tube-well Irrigated area), X5 (Irrigated area by other sources), X6 (Consumption of chemical fertilizers (NPK) Kg. /ha.), X7 (Number of wooden plough), X8 (Number of iron plough), X9 (Number of harrows and cultivators), X10 (Number of thresher machines), X11(Number of sprayers), X12 (Number of sowing instruments), X13 (Number of tractors) and X14 (Consumption of insecticides and pesticides (in Kg. /000 ha.). The entire data during 2001-2005 and 2006- 2010 have been taken and 5 years average value is taken into consideration, based on secondary sources obtained from various government, organizations, master plan report, economic abstracts, district census handbooks and village and town directories etc,. put on a standard computer programmed SPSS and the results obtained have been properly tabulated.

Keywords: agricultural technology, environmental implications, health hazards, socio-economic problems

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Authors: Khalid Alshallash

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Small fragments of the roots of some Rumex species including R. obtusifolius and R. crispus have been found to regenerate readily, contributing to the severity of infestations by these very common, widespread and difficult to control perennial weeds of agricultural crops and grasslands. Their root fragments are usually created during routine agricultural practices. We found that fresh root fragments of both species containing 65-70 % of moisture, progressively lose their moisture content when desiccated under controlled growth room conditions matching summer weather of southeast England, with the greatest reduction occurring in the first 48 hours. Probability of shoot emergence and the time taken for emergence in glasshouse conditions were also reduced significantly by desiccation, with R. obtusifolius least affected up to 48-hour. However, the effects converged after 120 hours. In contrast, R. obtusifolius was significantly slower to emerge after up to 48 hours desiccation, again effects converging after longer periods, R. crispus entirely failed to emerge at 120 hours. The dry weight of emerged shoots was not significantly different between the species, until desiccated for 96 hours when R. obtusifolius was significantly reduced. At 120 hours, R. obtusifolius did not emerge. In outdoor trials, desiccation for 24 or 48 hours had less effect on emergence when planted at the soil surface or up to 10 cm of depth, compared to deeper plantings. In both species, emergence was significantly lower when desiccated fragments were planted at 15 or 20 cm. Time taken for emergence was not significantly different between the species until planted at 15 or 20 cm when R. obtusifolius was slower than R. crispus and reduced further by increasing desiccation. Similar variation in effects of increasing soil depth interacting with increasing desiccation was found in reductions in dry weight, the number of tillers and leaf area, with R obtusifolius generally but not exclusively better able to withstand more extreme trial conditions. Our findings suggest that infestations of these highly troublesome weeds may be partly controlled by appropriate agricultural practices, notably exposing cut fragments to drying environmental conditions followed by deep burial.

Keywords: regeneration, root fragment, rumex crispus, rumex obtusifolius

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Authors: S. Srinivasan, E. Cretu

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The information flow (e.g. block-diagram or signal flow graph) paradigm for the design and simulation of Microelectromechanical (MEMS)-based systems allows to model MEMS devices using causal transfer functions easily, and interface them with electronic subsystems for fast system-level explorations of design alternatives and optimization. Nevertheless, the physical bi-directional coupling between different energy domains is not easily captured in causal signal flow modeling. Moreover, models of fundamental components acting as building blocks (e.g. gap-varying MEMS capacitor structures) depend not only on the component, but also on the specific excitation mode (e.g. voltage or charge-actuation). In contrast, the energy flow modeling paradigm in terms of generalized across-through variables offers an acausal perspective, separating clearly the physical model from the boundary conditions. This promotes reusability and the use of primitive physical models for assembling MEMS devices from primitive structures, based on the interconnection topology in generalized circuits. The physical modeling capabilities of Simscape have been used in the present work in order to develop a MEMS library containing parameterized fundamental building blocks (area and gap-varying MEMS capacitors, nonlinear springs, displacement stoppers, etc.) for the design, simulation and optimization of MEMS inertial sensors. The models capture both the nonlinear electromechanical interactions and geometrical nonlinearities and can be used for both small and large signal analyses, including the numerical computation of pull-in voltages (stability loss). Simscape behavioral modeling language was used for the implementation of reduced-order macro models, that present the advantage of a seamless interface with Simulink blocks, for creating hybrid information/energy flow system models. Test bench simulations of the library models compare favorably with both analytical results and with more in-depth finite element simulations performed in ANSYS. Separate MEMS-electronic integration tests were done on closed-loop MEMS accelerometers, where Simscape was used for modeling the MEMS device and Simulink for the electronic subsystem.

Keywords: across-through variables, electromechanical coupling, energy flow, information flow, Matlab/Simulink, MEMS, nonlinear, pull-in instability, reduced order macro models, Simscape

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Authors: Teklay Tesfay, Gebreyesus Brhane Tesfahunegn, Abadi Berhane, Selemawit Girmay

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Adjusting the proper sowing date of a crop at a particular location with a changing climate is an essential management option to maximize crop yield. However, determining the optimum sowing date for rainfed maize production through field experimentation requires repeated trials for many years in different weather conditions and crop management. To avoid such long-term experimentation to determine the optimum sowing date, crop models such as AquaCrop are useful. Therefore, the overall objective of this study was to evaluate the performance of AquaCrop model in simulating maize productivity under varying sowing dates. A field experiment was conducted for two consecutive cropping seasons by deploying four maize seed sowing dates in a randomized complete block design with three replications. Input data required to run this model are stored as climate, crop, soil, and management files in the AquaCrop database and adjusted through the user interface. Observed data from separate field experiments was used to calibrate and validate the model. AquaCrop model was validated for its performance in simulating the green canopy and aboveground biomass of maize for the varying sowing dates based on the calibrated parameters. Results of the present study showed that there was a good agreement (an overall R2 =, Ef= d= RMSE =) between measured and simulated values of the canopy cover and biomass yields. Considering the overall values of the statistical test indicators, the performance of the model to predict maize growth and biomass yield was successful, and so this is a valuable tool help for decision-making. Hence, this calibrated and validated model is suggested to use for determining optimum maize crop sowing date for similar climate and soil conditions to the study area, instead of conducting long-term experimentation.

Keywords: AquaCrop model, calibration, validation, simulation

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Authors: Beata Zima, Octavio A. Márquez Reyes, Masoud Mohammadgholiha, Jochen Moll, Luca de Marchi

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This document presents the approach of using compressed sensing in signal encoding and information transferring within a guided wave sensor network, comprised of specially designed frequency steerable acoustic transducers (FSATs). Wave propagation in a damaged plate was simulated using commercial FEM-based software COMSOL. Guided waves were excited by means of FSATs, characterized by the special shape of its electrodes, and modeled using PIC255 piezoelectric material. The special shape of the FSAT, allows for focusing wave energy in a certain direction, accordingly to the frequency components of its actuation signal, which makes available a larger monitored area. The process begins when a FSAT detects and records reflection from damage in the structure, this signal is then encoded and prepared for transmission, using a combined approach, based on Compressed Sensing Matching Pursuit and Quadrature Amplitude Modulation (QAM). After codification of the signal is in binary chars the information is transmitted between the nodes in the network. The message reaches the last node, where it is finally decoded and processed, to be used for damage detection and localization purposes. The main aim of the investigation is to determine the location of detected damage using reconstructed signals. The study demonstrates that the special steerable capabilities of FSATs, not only facilitate the detection of damage but also permit transmitting the damage information to a chosen area in a specific direction of the investigated structure.

Keywords: data compression, ultrasonic communication, guided waves, FEM analysis

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Authors: Maaly Jarrah

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Oral fluency in the target language is what many second language learners hope to achieve by living abroad. Research in the past has demonstrated the role informal environments play in improving L2 learners' oral fluency. However, living in the target country and being part of its community does not ensure the development of oral fluency skills. L2 learners' desire to communicate and access to speaking opportunities in the host community are key in achieving oral fluency in the target language. This study attempts to identify differences in oral fluency, specifically speech rate, between learners who communicate in the L2 outside the classroom and those who do not. In addition, as the desire to communicate is a crucial factor in developing oral fluency, this study investigates whether or not learners' desire to speak the L2 outside the classroom plays a role in their frequency of L2 use outside the classroom. Finally, given the importance of the availability of speaking opportunities for L2 learners in order to practice their speaking skills, this study reports on the participants' perceptions of the speaking opportunities accessible to them in the target community while probing whether or not their perceptions differed based on their oral fluency level and their desire to communicate. The results suggest that exposure to the target language and daily communication with the native speakers is strongly related to the development of learners' oral fluency. Moreover, the findings suggest that learners' desire to communicate affects their frequency of communication in their L2 outside the classroom. At the same time, all participants, regardless of their oral fluency level and their desire to communicate, asserted that speaking opportunities beyond the classroom are very limited. Finally, the study finds there are marked differences in the perceptions learners have regarding opportunities for learning offered by the same language program. After reporting these results, the study concludes with recommendations for ESL programs that serve international students.

Keywords: ESL programs, L2 Learners, oral fluency, second language

Procedia PDF Downloads 477

Authors: Jaypraksh Show, Pooja Rawat

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Experiences are the fundamental aspects of understanding of ourslves and the world around, leading to wisdom. In the path of wisdom, explorative reflection is the process through which we integrate our experiences, weave them into autobiographical narratives. Further, Neisser, a psychologist, and philosopher, thinks ‘ourselves’ is the wide web of different concepts which help us to understand the world, he called it the conceptual self. The conceptual self, as the storehouse of experiences and different concepts, develops a wiser individual narrative. Thus, Wisdom can be conceived as the expression of the Self. Drawing from this, the current work explores the autobiographies of young adults, focusing on their narrative self and foundations of wisdom through narrative analysis. Using the corresponding interview data, we will shed light on the way they exploratively reflect on challenging situations and use their narrative experiences and conceptual understanding. The aim of this study is to understand the ‘conceptual wiser-self’.

Keywords: wisdom, self, conceptual self, narrative self, autobiography, narrative analysis

Procedia PDF Downloads 141

Authors: Yi-Hsiu Lai

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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 462