Search results for: open-ended laboratory
1910 Combination of Electrodialysis and Electrodeionization for Treatment of Condensate from Ammonium Nitrate Production
Authors: Lubomir Machuca, Vit Fara
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Ammonium nitrate (AN) is produced by the reaction of ammonia and nitric acid, and a waste condensate is obtained. The condensate contains pure AN in concentration up to 10g/L. The salt content in the condensate is too high to discharge immediately into the river thus it must be treated. This study is concerned with the treatment of condensates from an industrial AN production by combination of electrodialysis (ED) and electrodeionization (EDI). The condensate concentration was in range 1.9–2.5g/L of AN. A pilot ED module with 25 membrane pairs following by a laboratory EDI module with 10 membrane pairs operated continuously during 800 hours. Results confirmed that the combination of ED and EDI is suitable for the condensate treatment.Keywords: desalination, electrodialysis, electrodeionization, fertilizer industry
Procedia PDF Downloads 2401909 In-situ and Laboratory Characterization of Fiji Lateritic Soils
Authors: Faijal Ali, Darga Kumar N., Ravikant Singh, Rajnil Lal
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Fiji has three major landforms such as plains, low mountains, and hills. The low land soils are formed on beach sand. Fiji soils contain high concentration of iron (III), aluminum oxides and hydroxides. The soil possesses reddish or yellowish colour. The characterization of lateritic soils collected from different locations along the national highway in Viti Levu, Fiji Islands. The research has been carried out mainly to understand the physical and strength properties to assess their suitability for the highway and building construction. In this paper, the field tests such as dynamic cone penetrometer test, field vane shear, field density and laboratory tests such as unconfined compression stress, compaction, grain size analysis and Atterberg limits are conducted. The test results are analyzed and presented. From the results, it is revealed that the soils are having more percentage of silt and clay which is more than 80% and 5 to 15% of fine to medium sand is noticed. The dynamic cone penetrometer results up to 3m depth had similar penetration resistance. For the first 1m depth, the rate of penetration is found 300mm per 3 to 4 blows. In all the sites it is further noticed that the rate of penetration at depths beyond 1.5 m is decreasing for the same number of blows as compared to the top soil. From the penetration resistance measured through dynamic cone penetrometer test, the California bearing ratio and allowable bearing capacities are 4 to 5% and 50 to 100 kPa for the top 1m layer and below 1m these values are increasing. The California bearing ratio of these soils for below 1m depth is in the order of 10% to 20%. The safe bearing capacity of these soils below 1m and up to 3m depth is varying from 150 kPa to 250 kPa. The field vane shear was measured within a depth of 1m from the surface and the values were almost similar varying from 60 kPa to 120 kPa. The liquid limit and plastic limits of these soils are in the range of 40 to 60% and 20 to 25%. Overall it is found that the top 1m soil along the national highway in majority places possess a soft to medium stiff behavior with low to medium bearing capacity as well low California bearing ratio values. It is recommended to ascertain these soils behavior in terms of geotechnical parameters before taking up any construction activity.Keywords: California bearing ratio, dynamic cone penetrometer test, field vane shear, unconfined compression stress.
Procedia PDF Downloads 1861908 Developing a Methodology to Examine Psychophysiological Responses during Stress Exposure and Relaxation: An Experimental Paradigm
Authors: M. Velana, G. Rinkenauer
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Nowadays, nurses are facing unprecedented amounts of pressure due to the ongoing global health demands. Work-related stress can cause a high physical and psychological workload, which can lead, in turn, to burnout. On the physiological level, stress triggers an initial activation of the sympathetic nervous and adrenomedullary systems resulting in increases in cardiac activity. Furthermore, activation of the hypothalamus-pituitary-adrenal axis provokes endocrine and immune changes leading to the release of cortisol and cytokines in an effort to re-establish body balance. Based on the current state of the literature, it has been identified that resilience and mindfulness exercises among nurses can effectively decrease stress and improve mood. However, it is still unknown what relaxation techniques would be suitable for and to what extent would be effective to decrease psychophysiological arousal deriving from either a physiological or a psychological stressor. Moreover, although cardiac activity and cortisol are promising candidates to examine the effectiveness of relaxation to reduce stress, it still remains to shed light on the role of cytokines in this process so as to thoroughly understand the body’s response to stress and to relaxation. Therefore, the main aim of the present study is to develop a comprehensive experimental paradigm and assess different relaxation techniques, namely progressive muscle relaxation and a mindfulness exercise originating from cognitive therapy by means of biofeedback, under highly controlled laboratory conditions. An experimental between-subject design will be employed, where 120 participants will be randomized either to a physiological or a psychological stress-related experiment. Particularly, the cold pressor test refers to a procedure in which the participants have to immerse their non-dominant hands into ice water (2-3 °C) for 3 min. The participants are requested to keep their hands in the water throughout the whole duration. However, they can immediately terminate the test in case it would be barely tolerable. A pre-test anticipation phase and a post-stress period of 3 min, respectively, are planned. The Trier Social Stress Test will be employed to induce psychological stress. During this laboratory stressor, the participants are instructed to give a 5-min speech in front of a committee of communication specialists. Before the main task, there is a 10-min anticipation period. Subsequently, participants are requested to perform an unexpected arithmetic task. After stress exposure, the participants will perform one of the relaxation exercises (treatment condition) or watch a neutral video (control condition). Electrocardiography, salivary samples, and self-report will be collected at different time points. The preliminary results deriving from the pilot study showed that the aforementioned paradigm could effectively induce stress reactions and that relaxation might decrease the impact of stress exposure. It is of utmost importance to assess how the human body responds under different stressors and relaxation exercises so that an evidence-based intervention could be transferred in a clinical setting to improve nurses’ general health. Based on suggestive future laboratory findings, the research group plans to conduct a pilot-level randomized study to decrease stress and promote well-being among nurses who work in the stress-riddled environment of a hospital located in Northern Germany.Keywords: nurses, psychophysiology, relaxation, stress
Procedia PDF Downloads 1101907 An Evaluation of Medical Waste in Health Facilities through Data Envelopment Analysis (DEA) Method: Turkey-Amasya Public Hospitals Union Model
Authors: Murat Iskender Aktaş, Sadi Ergin, Rasime Acar Aktaş
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In the light of fast-paced changes and developments in the health sector, the Ministry of Health started a new structuring with decree law numbered 663 within the scope of the Project of Transformation in Health. Accordingly, hospitals should ensure patient satisfaction through more efficient, more effective use of resources and sustainable finance by placing patients in the centre and should operate to increase efficiency to its maximum level while doing these. Within this study, in order to find out how efficient the hospitals were in terms of medical waste management between the years 2011-2014, the data from six hospitals of Amasya Public Hospitals Union were evaluated separately through Data Envelopment Analysis (DEA) method. First of all, input variables were determined. Input variables were the number of patients admitted to polyclinics, the number of inpatients in clinics, the number of patients who were operated and the number of patients who applied to the laboratory. Output variable was the cost of medical wastes in Turkish liras. Each hospital’s total medical waste level before and after public hospitals union; the amounts of average medical waste per patient admitted to polyclinics, per inpatient in clinics, per patient admitted to laboratory and per operated patient were compared within each group. In addition, average medical waste levels and costs were compared for Turkey in general and Europe in general. Paired samples t-test was used to find out whether the changes (increase-decrease) after public hospitals union were statistically significant. The health facilities that were unsuccessful in terms of medical waste management before and after public hospital union and the factors that caused this failure were determined. Based on the results, for each health facility that was ineffective in terms of medical waste management, the level of improvement required for each input was determined. The results of the study showed that there was an improvement in medical waste management applications after the health facilities became a member of public hospitals union; their medical waste levels were lower than the average of Turkey and Europe while the averages of cost of disposal were the highest.Keywords: medical waste management, cost of medical waste, public hospitals, data envelopment analysis
Procedia PDF Downloads 4151906 Analysis of Sentinel Epidemiological Surveillance of Severe Acute Respiratory Infections in the Republic of Kazakhstan during Seasons 2014/2015 - 2015/2016
Authors: Ardak Myrzabekova
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Sentinel epidemiological surveillance (SES) of severe acute respiratory infections (SARI) was introduced in the Republic of Kazakhstan in 2008. The purpose of this study was to analyze SES of flu among SARI patients in the Republic of Kazakhstan during last two flu seasons. Comparative analysis was conducted of SARI morbidity during 40 – 23 weeks of 2014/2015 (season 2014) and 2015/2016 (season 2015) in online base (http:\\ses.dec.kz). In the database during season 2014 were 1,398 SARI patients and 1,985 patients during season 2015. Individual data (clinical, epidemiological and laboratory) of SARI cases were collected based on the questionnaire and were put into the flu electronic system. The studied population was residents of the Republic of Kazakhstan who addressed for medical help in 24 sentinel in-patient clinics in 9 sentinel regions of the country. Swabs from nose and throat were taken for laboratory testing from SARI patients who met the standard case definition. The samples were examined in virology labs of sentinel regions using PCR and 'AmpliSens' test systems made in Russia. The first positive results for flu during season 2014 were obtained on 48 week, during season 2015 – on 46 week. The increase of the number of hospitalized SARI patients was observed during 42 week of 2015 – 01 week of 2016, and during 03 - 06 weeks of 2016, with fluctuating SARI incidence rate from 171 to 444 per 1,000 hospitalized. The highest SARI incidence rate during season 2014 were observed during 01 - 03 weeks of 2015: from 389 to 466 per 1,000 hospitalized. Patients admitted to the ICU during season 2015 were 3.0% (60) SARI patients, compared to 2.7% (38) in 2014 (p=0.3), obtaining oxygen therapy 1.0% (21) compared to 0.3% (5), accordingly, (р=0.009); with shortness of breath 74.8% (1,486) compared to 72.6% (1,015), (р=0.07); with impairment of consciousness 1.0% (21) compared to 0.6% (9), (р=0.11); with muscle pain 19.3% (384) compared to 13.6% (191), (р < 0.001); with joint pain 13.3% (265) compared to 9.3% (131), (p < 0.001). During season 2015 the prevailing subtype of flu А was А/Н1N1-09, it was observed mainly in the age group 30-64: 32.5% (169/520). During season 2014 flu А/Н3N2 was observed mainly in the age group 15-29: 43.6% (106/243). Among children under 14 flu А/Н1N1-09 during season 2015 was 37.3% (194/520), during season 2014 flu А/Н3N2 – 34.9% (85/243). Earlier beginning of the flu season was noted in 2015-2016 and a longer period of hospitalization of SARI patients, with high SARI morbidity rates, unlike season 2014-2015. Season 2015-2016 was characterized by prevailing circulation of virus of flu А/Н1N1-09, mainly in the age group 30-64, and also among children under 14. During season 2014-2015 the virus circulating in the country was А/Н3N2, which was observed mainly in the age group 15-29 and among children under 14.Keywords: flu, electronic system, sentinel epidemiological surveillance, severe acute respiratory infections
Procedia PDF Downloads 2271905 The Existence of Beauveria bassiana in the Third Generation of Corn Seedling
Authors: Itji Diana Daud, Nuniek Widiayani
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The fungus Beauveria bassiana can be endophytic in maize. The fungus was recovered in culture from stems, leaves and roots after a month planting. This phenomenon was shown until the third generation of the corn. The result from laboratory shows that B. bassiana appear in F1, F2 and F3 in order 70, 80 and 90% in the roots, 80% in the stems in all generation, 90, 80 and 70% in leaves. In CFU’s ml-1 of B. bassiana in corn seed, show F1 was 8.9 x 106, F2 was 8.1 x 106 and F3 was 7.8 x 106. The research showed that B. Bassiana as endophyte still remain to the third generation. Innovation to the corn seed which is endophyte seed is essential to protect from the attack of corn borer and to avoid the usage of insecticide.Keywords: endophytic, recovered, third generation, Beauveria bassiana
Procedia PDF Downloads 2831904 Laboratory Diagnostic Testing of Peste des Petits Ruminants in Georgia
Authors: Nino G. Vepkhvadze, Tea Enukidze
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Every year the number of countries around the world face the risk of the spread of infectious diseases that bring significant ecological and social-economic damage. Hence, the importance of food product safety is emphasized that is the issue of interest for many countries. To solve them, it’s necessary to conduct preventive measures against the diseases, have accurate diagnostic results, leadership, and management. The Peste des petits ruminants (PPR) disease is caused by a morbillivirus closely related to the rinderpest virus. PPR is a transboundary disease as it emerges and evolves, considered as one of the top most damaging animal diseases. The disease imposed a serious threat to sheep-breeding when the farms of sheep, goats are significantly growing within the country. In January 2016, PPR was detected in Georgia. Up to present the origin of the virus, the age relationship of affected ruminants and the distribution of PPRV in Georgia remains unclear. Due to the nature of PPR, and breeding practices in the country, reemerging of the disease in Georgia is highly likely. The purpose of the studies is to provide laboratories with efficient tools allowing the early detection of PPR emergence and re-emergences. This study is being accomplished under the Biological Threat Reduction Program project with the support of the Defense Threat Reduction Agency (DTRA). The purpose of the studies is to investigate the samples and identify areas at high risk of the disease. Georgia has a high density of small ruminant herds bred as free-ranging, close to international borders. Kakheti region, Eastern Georgia, will be considered as area of high priority for PPR surveillance. For this reason, in 2019, in Kakheti region investigated n=484 sheep and goat serum and blood samples from the same animals, utilized serology and molecular biology methods. All samples were negative by RT-PCR, and n=6 sheep samples were seropositive by ELISA-Ab. Future efforts will be concentrated in areas where the risk of PPR might be high such as international bordering regions of Georgia. For diagnostics, it is important to integrate the PPRV knowledge with epidemiological data. Based on these diagnostics, the relevant agencies will be able to control the disease surveillance.Keywords: animal disease, especially dangerous pathogen, laboratory diagnostics, virus
Procedia PDF Downloads 1151903 Clinical Risk Score for Mortality and Predictors of Severe Disease in Adult Patients with Dengue
Authors: Siddharth Jain, Abhenil Mittal, Surendra Kumar Sharma
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Background: With its recent emergence and re-emergence, dengue has become a major international public health concern, imposing significant financial burden especially in developing countries. Despite aggressive control measures in place, India experienced one of its largest outbreaks in 2015 with Delhi being most severely affected. There is a lack of reliable predictors of disease severity and mortality in dengue. The present study was carried out to identify these predictors during the 2015 outbreak. Methods: This prospective observational study conducted at an apex tertiary care center in Delhi, India included confirmed adult dengue patients admitted between August-November 2015. Patient demographics, clinical details, and laboratory findings were recorded in a predesigned proforma. Appropriate statistical tests were used to summarize and compare the clinical and laboratory characteristics and derive predictors of mortality and severe disease, while developing a clinical risk score for mortality. Serotype analysis was also done for 75 representative samples to identify the dominant serotypes. Results: Data of 369 patients were analyzed (mean age 30.9 years; 67% males). Of these, 198 (54%) patients had dengue fever, 125 (34%) had dengue hemorrhagic fever (DHF Grade 1,2)and 46 (12%) developed dengue shock syndrome (DSS). Twenty two (6%) patients died. Late presentation to the hospital (≥5 days after onset) and dyspnoea at rest were identified as independent predictors of severe disease. Age ≥ 24 years, dyspnoea at rest and altered sensorium were identified as independent predictors of mortality. A clinical risk score was developed (12*age + 14*sensorium + 10*dyspnoea) which, if ≥ 22, predicted mortality with a high sensitivity (81.8%) and specificity (79.2%). The predominant serotypes in Delhi (2015) were DENV-2 and DENV-4. Conclusion: Age ≥ 24 years, dyspnoea at rest and altered sensorium were identified as independent predictors of mortality. Platelet counts did not determine the outcome in dengue patients. Timely referral/access to health care is important. Development and use of validated predictors of disease severity and simple clinical risk scores, which can be applied in all healthcare settings, can help minimize mortality and morbidity, especially in resource limited settings.Keywords: dengue, mortality, predictors, severity
Procedia PDF Downloads 3071902 Enhancing the Quality of Silage Bales Produced by a Commercial Scale Silage Producer in Northern province, Sri Lanka: A Step Toward Supporting Smallholder Dairy Farmers in the Northern Province Sri Lanka
Authors: Harithas Aruchchunan
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Silage production is an essential aspect of dairy farming, used to provide high-quality feed to ruminants. However, dairy farmers in Northern Province Sri Lanka are facing multiple challenges that compromise the quality and quantity of silage produced. To tackle these challenges, promoting silage feeding has become an essential component of sustainable dairy farming practices. In this study, silage bale samples were collected from a newly started silage baling factory in Jaffna, Northern province and their quality was analysed at the Veterinary Research Institute laboratory in Kandy in March 2023. The results show the nutritional composition of three Napier grass cultivars: Super Napier, CO6, and Indian Red Napier (BH18). The main parameters analysed were dry matter, pH, lactic acid, soluble carbohydrate, ammonia nitrogen, ash, crude protein, NDF, and ADF. The results indicate that Super Napier and CO6 have higher crude protein content and lower ADF levels, making them suitable for producing high-quality silage. The pH levels of all three cultivars were safe, and the ammonia nitrogen levels were considered appropriate. However, laboratory results indicate that the quality of silage bales produced can be further enhanced. Dairy farmers should be encouraged to adopt these cultivars to achieve better yields as they are high in protein and are better suited to Northern Province's soil and climate. Therefore, it is vital to educate small-scale fodder producers, who supply the raw material to silage factories, on the best practices of cultivating these new cultivars. To improve silage bale production and quality in Northern Province Sri Lanka, we recommend increasing public awareness about silage feeding, providing education and training to dairy farmers and small-scale fodder producers on modern silage production techniques and improving the availability of raw materials for silage production. Additionally, Napier grass cultivars need to be promoted among dairy farmers for better production and quality of silage bales. Failing to improve the quality and quantity of silage bale production could not only lead to the decline of dairy farming in Northern Province Sri Lanka but also the negative impact on the economyKeywords: silage bales, dairy farming, economic crisis, Sri Lanka
Procedia PDF Downloads 921901 Utilization of a Telepresence Evaluation Tool for the Implementation of a Distant Education Program
Authors: Theresa Bacon-Baguley, Martina Reinhold
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Introduction: Evaluation and analysis are the cornerstones of any successful program in higher education. When developing a program at a distant campus, it is essential that the process of evaluation and analysis be orchestrated in a timely manner with tools that can identify both the positive and negative components of distant education. We describe the utilization of a newly developed tool used to evaluate and analyze the successful expansion to a distant campus using Telepresence Technology. Like interactive television, Telepresence allows live interactive delivery but utilizes broadband cable. The tool developed is adaptable to any distant campus as the framework for the tool was derived from a systematic review of the literature. Methodology: Because Telepresence is a relatively new delivery system, the evaluation tool was developed based on a systematic review of literature in the area of distant education and ITV. The literature review identified four potential areas of concern: 1) technology, 2) confidence in the system, 3) faculty delivery of the content and, 4) resources at each site. Each of the four areas included multiple sub-components. Benchmark values were determined to be 80% or greater positive responses to each of the four areas and the individual sub-components. The tool was administered each semester during the didactic phase of the curriculum. Results: Data obtained identified site-specific issues (i.e., technology access, student engagement, laboratory access, and resources), as well as issues common at both sites (i.e., projection screen size). More specifically, students at the parent location did not have adequate access to printers or laboratory space, and students at the distant campus did not have adequate access to library resources. The evaluation tool identified that both sites requested larger screens for visualization of the faculty. The deficiencies were addressed by replacing printers, including additional orientation for students on library resources and increasing the screen size of the Telepresence system. When analyzed over time, the issues identified in the tool as deficiencies were resolved. Conclusions: Utilizing the tool allowed adjustments of the Telepresence delivery system in a timely manner resulting in successful implementation of an entire curriculum at a distant campus.Keywords: physician assistant, telepresence technology, distant education, assessment
Procedia PDF Downloads 1241900 Training of Sensors for Early Warning System of Rainfall Induced Landslides
Authors: M. Naresh, Pratik Chaturvedi, Srishti Yadav, Varun Dutt, K. V. Uday
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Changes in the Earth’s climate are likely to increase natural hazards such as drought, floods, earthquakes, landslides, etc. The present study focusing on to early warning systems (EWS) of landslides, major issues in Himalayan region without prominence to deforestation, encroachments and un-engineered cutting of slopes and reforming for infrastructural purposes. EWS can be depicted by conducting a series of flume tests using micro-electro mechanical systems sensors data after reaching threshold values under controlled laboratory conditions. Based on the threshold value database, an alert will be sent via SMS.Keywords: slope-instability, flume test, sensors, early warning system
Procedia PDF Downloads 2661899 Corrosion Inhibition of Mild Steel in 20% Sulfuric Acid
Authors: M. Dekmouche, M. Hadjada, Z. Rahmani, M. Saidi
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The effect of iodide ions on the corrosion inhibition of mild steel in 20% sulfuric acid in the presence of 3-méthylthio-5-p-méthoxyphényl-1,2-dithiolylium against anion (I-) A1 synthesized in our laboratory,was studied by different electrochemical techniques such as electrochemical impedance spectroscopy, potentiodynamic polarization. The obtained results showed that A1 effectively reduces the corrosion rate of steel. The adsorption of 3-méthylthio-5-p-méthoxyphényl-1,2-dithiolylium against anion (I-) followed Langmuir and temkin adsorption isotherm.Keywords: steel XC52, corrosion, inhibition, 3-méthylthio-5-p-méthoxyphényl-1, 2-dithiolylium against anion (I-) , sulfuric acid
Procedia PDF Downloads 3281898 Characteristics of Clinical and Diagnostic Aspects of Benign Diseases of Cervi̇x in Women
Authors: Gurbanova J., Majidova N., Ali-Zade S., Hasanova A., Mikailzade P.
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Currently, the problem of oncogynecological diseases is widespread and remains relevant in terms of quantitative growth. It is known that due to the increase in the number of benign diseases of the cervix, the development of precancerous conditions occurs. Benign diseases of the cervix represent the most common gynecological problem, which are often precursors of malignant neoplasms, especially cervical cancer. According to statistics, benign diseases of the cervix cover 25-45% of all gynecological diseases. Among women's oncogynecological diseases, cervical cancer ranks second in the world after breast cancer and ranks first in the mortality rate among oncological diseases in economically underdeveloped countries. We performed a comprehensive clinical and laboratory examination of 130 women aged 18 to 73 with benign cervical diseases. 59 (38.5%) women of reproductive age, as well as 39 (30%) premenopausal and 41 (31.5%) menopausal patients, participated in the study. Detailed anamnesis was collected from all patients, objective and gynecological examination was performed, laboratory and instrumental examinations (USM, IPV DNA, smear microscopy, and PCR bacteriological examination of sexually transmitted infections), simple and extended colposcopy, liquid-based РАР-smear smear and РАР-classic smear examinations were conducted. As a result of the research, the following nosological forms were found in women with benign diseases of the cervix: non-specific vaginitis in 10 (7.7%) cases; ectopia, endocervicitis - 60(46.2%); cervical ectropion - 7(5.4%); cervical polyp - 9(6.9%); cervical leukoplakia - 15(11.5%); atrophic vaginitis - 7(5.4%); condyloma - 12(9.2%); cervical stenosis - 2(1.5%); endometriosis of the cervix - was noted in 8 (6.2%) cases (p<0.001), respectively. Characteristics of the menstrual cycle among the examined women: normal cycle in 97 (74.6%) cases; oligomenorrhea – 23 (17.7%); polymenorrhea – 4(3.1%); algomenorrhea – noted in 6 (4.6%) cases (p<0.001). Cytological examination showed that: the specificity of liquid-based cytology was 76.2%, and the traditional PAP test was set at 70.6%. The overall diagnostic value was calculated to be 86% in liquid-based cytology and 78.5% in conventional PAP tests. Treatment of women with benign diseases of the cervix was carried out by diathermocoagulation method and "FOTEK EA 141M" device. It should be noted that 6 months after the treatment, after treatment with the "FOTEK EA 141M" device, there was no relapse in any patient. Recurrence was found in 23.7% of patients after diathermoelectrocoagulation. Thus, it is clear from the above that the study of cervical pathologies, the determination of optimal examinations, and effective treatment methods is one of the urgent problems facing obstetrics and gynecology.Keywords: cervical cancer, cytological examination, PAP-smear, non-specific vaginitis
Procedia PDF Downloads 1171897 Characterization, Replication and Testing of Designed Micro-Textures, Inspired by the Brill Fish, Scophthalmus rhombus, for the Development of Bioinspired Antifouling Materials
Authors: Chloe Richards, Adrian Delgado Ollero, Yan Delaure, Fiona Regan
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Growing concern about the natural environment has accelerated the search for non-toxic, but at the same time, economically reasonable, antifouling materials. Bioinspired surfaces, due to their nano and micro topographical antifouling capabilities, provide a hopeful approach to the design of novel antifouling surfaces. Biological organisms are known to have highly evolved and complex topographies, demonstrating antifouling potential, i.e. shark skin. Previous studies have examined the antifouling ability of topographic patterns, textures and roughness scales found on natural organisms. One of the mechanisms used to explain the adhesion of cells to a substrate is called attachment point theory. Here, the fouling organism experiences increased attachment where there are multiple attachment points and reduced attachment, where the number of attachment points are decreased. In this study, an attempt to characterize the microtopography of the common brill fish, Scophthalmus rhombus, was undertaken. Scophthalmus rhombus is a small flatfish of the family Scophthalmidae, inhabiting regions from Norway to the Mediterranean and the Black Sea. They reside in shallow sandy and muddy coastal areas at depths of around 70 – 80 meters. Six engineered surfaces (inspired by the Brill fish scale) produced by a 2-photon polymerization (2PP) process were evaluated for their potential as an antifouling solution for incorporation onto tidal energy blades. The micro-textures were analyzed for their AF potential under both static and dynamic laboratory conditions using two laboratory grown diatom species, Amphora coffeaeformis and Nitzschia ovalis. The incorporation of a surface topography was observed to cause a disruption in the growth of A. coffeaeformis and N. ovalis cells on the surface in comparison to control surfaces. This work has demonstrated the importance of understanding cell-surface interaction, in particular, topography for the design of novel antifouling technology. The study concluded that biofouling can be controlled by physical modification, and has contributed significant knowledge to the use of a successful novel bioinspired AF technology, based on Brill, for the first time.Keywords: attachment point theory, biofouling, Scophthalmus rhombus, topography
Procedia PDF Downloads 1071896 Description of a Structural Health Monitoring and Control System Using Open Building Information Modeling
Authors: Wahhaj Ahmed Farooqi, Bilal Ahmad, Sandra Maritza Zambrano Bernal
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In view of structural engineering, monitoring of structural responses over time is of great importance with respect to recent developments of construction technologies. Recently, developments of advanced computing tools have enabled researcher’s better execution of structural health monitoring (SHM) and control systems. In the last decade, building information modeling (BIM) has substantially enhanced the workflow of planning and operating engineering structures. Typically, building information can be stored and exchanged via model files that are based on the Industry Foundation Classes (IFC) standard. In this study a modeling approach for semantic modeling of SHM and control systems is integrated into the BIM methodology using the IFC standard. For validation of the modeling approach, a laboratory test structure, a four-story shear frame structure, is modeled using a conventional BIM software tool. An IFC schema extension is applied to describe information related to monitoring and control of a prototype SHM and control system installed on the laboratory test structure. The SHM and control system is described by a semantic model applying Unified Modeling Language (UML). Subsequently, the semantic model is mapped into the IFC schema. The test structure is composed of four aluminum slabs and plate-to-column connections are fully fixed. In the center of the top story, semi-active tuned liquid column damper (TLCD) is installed. The TLCD is used to reduce effects of structural responses in context of dynamic vibration and displacement. The wireless prototype SHM and control system is composed of wireless sensor nodes. For testing the SHM and control system, acceleration response is automatically recorded by the sensor nodes equipped with accelerometers and analyzed using embedded computing. As a result, SHM and control systems can be described within open BIM, dynamic responses and information of damages can be stored, documented, and exchanged on the formal basis of the IFC standard.Keywords: structural health monitoring, open building information modeling, industry foundation classes, unified modeling language, semi-active tuned liquid column damper, nondestructive testing
Procedia PDF Downloads 1511895 Research Cooperation between of Ukraine in Terms of Food Chain Safety Control in the Frame of MICRORISK Project
Authors: Kinga Wieczorek, Elzbieta Kukier, Remigiusz Pomykala, Beata Lachtara, Renata Szewczyk, Krzysztof Kwiatek, Jacek Osek
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The MICRORISK project (Research cooperation in assessment of microbiological hazard and risk in the food chain) was funded by the European Commission under the FP7 PEOPLE 2012 IRSES call within the International Research Staff Exchange Scheme of Marie Curie Action and realized during years from 2014 to 2015. The main aim of the project was to establish a cooperation between the European Union (EU) and the third State in the area important from the public health point of view. The following organizations have been engaged in the activity: National Veterinary Research Institute (NVRI) in Pulawy, Poland (coordinator), French Agency for Food, Environmental and Occupational Health & Safety (ANSES) in Maisons Alfort, France, National Scientific Center Institute of Experimental and Clinical Veterinary Medicine (NSC IECVM), Kharkov and State Scientific and Research Institute of Laboratory Diagnostics and Veterinary and Sanitary Expertise (SSRILDVSE) Kijev Ukraine. The results of the project showed that Ukraine used microbiological criteria in accordance with Commission Regulation (EC) No 2073/2005 of 15 November 2005 on microbiological criteria for foodstuffs. Compliance concerns both the criteria applicable at the stage of food safety (retail trade), as well as evaluation criteria and process hygiene in food production. In this case, the Ukrainian legislation also provides application of the criteria that do not have counterparts in the food law of the European Union, and are based on the provisions of Ukrainian law. Partial coherence of the Ukrainian and EU legal requirements in terms of microbiological criteria for food and feed concerns microbiological parameters such as total plate count, coliforms, coagulase-positive Staphylococcus spp., including S. aureus. Analysis of laboratory methods used for microbiological hazards control in food production chain has shown that most methods used in the EU are well-known by Ukrainian partners, and many of them are routinely applied as the only standards in the laboratory practice or simultaneously used with Ukrainian methods. The area without any legislation, where the EU regulation and analytical methods should be implemented is the area of Shiga toxin producing E. coli, including E. coli O157 and staphylococcal enterotoxin detection. During the project, the analysis of the existing Ukrainian and EU data concerning the prevalence of the most important food-borne pathogens on different stages of food production chain was performed. Particularly, prevalence of Salmonella spp., Campylobacter spp., L. monocytogenes as well as clostridia was examined. The analysis showed that poultry meat still appears to be the most important food-borne source of Campylobacter and Salmonella in the UE. On the other hand, L. monocytogenes were seldom detected above the legal safety limit (100 cfu/g) among the EU countries. Moreover, the analysis revealed the lack of comprehensive data regarding the prevalence of the most important food-borne pathogens in Ukraine. The results of the MICRORISK project are networking activities among researches originations participating in the tasks will help with a better recognition of each other regarding very important, from the public health point of view areas such as microbiological hazards in the food production chain and finally will help to improve food quality and safety for consumers.Keywords: cooperation, European Union, food chain safety, food law, microbiological risk, Microrisk, Poland, Ukraine
Procedia PDF Downloads 3741894 Embryotoxicity of Nano-Iron Oxide (Fe2O3) to Bio-Indicator of Pollution of Land Helix Aspersa
Authors: S. Besnaci, S. Bensoltane, H. Locif, S. Saadi
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To validate an ecotoxicological approach to assessing toxicological effects caused by the oxide powder of nano-iron Fe2O3, we searched in the ecotoxicology laboratory cell bodies bio accumulators and bio-indicators of soil pollution the snail Helix aspersa. In this study, we evaluated the toxicity of nano Fe2O3 during a very sensitive phase of development H.aspersa (embryonic stage). During embryonic development, we observed in treated with various concentrations of nano Fe2O3 (1.25 g/l, 1.5 g/l, and 2 g/l) compared to control, the deformation of the membrane of the egg and accumulation of this molecule at the rear of the egg proven by the photographs, as with the influence on the hatching percentage.Keywords: eggs, embryotoxicity, Fe2O3, Helix aspersa, nanoparticles
Procedia PDF Downloads 3761893 Oviposition Responses of the Malaria Mosquito Anopheles gambiae sensu stricto to Hay Infusion Volatiles in Laboratory Bioassays and Investigation of Volatile Detection Methods
Authors: Lynda K. Eneh, Okal N. Mike, Anna-Karin Borg-Karlson, Ulrike Fillinger, Jenny M. Lindh
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The responses of individual gravid Anopheles gambiae sensu stricto (s.s.) to hay infusion volatiles were evaluated under laboratory conditions. Such infusions have long been known to be effective baits for monitoring mosquitoes that vector arboviral and filarial diseases but have previously not been tested for malaria vectors. Hay infusions were prepared by adding sun-dried Bermuda grass to lake water and leaving the mixture in a covered bucket for three days. The proportions of eggs laid by gravid An. gambiae s.s. in diluted (10%) and concentrated infusions ( ≥ 25%) was compared to that laid in lake water in two-choice egg-count bioassays. Furthermore, with the aim to develop a method that can be used to collect volatiles that influence the egg-laying behavior of malaria mosquitoes, different volatile trapping methods were investigated. Two different polymer-traps eluted using two different desorption methods and three parameters were investigated. Porapak®-Q traps and solvent desorption was compared to Tenax®-TA traps and thermal desorption. The parameters investigated were: collection time (1h vs. 20h), addition of salt (0.15 g/ml sodium chloride (NaCl) vs. no NaCl), and stirring the infusion (0 vs. 300 rpm). Sample analysis was with gas chromatography-mass spectrometry (GC-MS). An. gambiae s.s was ten times less likely to lay eggs in concentrated hay infusion than in lake water. The volatiles were best characterized by thermally desorbed Tenax traps, collected for 20 hours from infusion aliquots with sodium chloride added. Ten volatiles identified from headspace and previously indicated as putative oviposition semiochemicals for An. gambiae s.s. or confirmed semiochemicals for other mosquito species were tested in egg-count bioassays. Six of these (3-methylbutanol, phenol, 4-methylphenol, nonanal, indole and 3-methylindole), when added to lake water, were avoided for egg-laying when lake water was offered as the alternative in dual-choice egg count bioassays. These compounds likely contribute to the unfavorable oviposition responses towards hay infusions. This difference in oviposition response of different mosquito species should be considered when designing control measures.Keywords: Anopheles gambiae, oviposition behaviour, egg-count cage bioassays, hay infusions, volatile detection, semiochemicals
Procedia PDF Downloads 3501892 Nonlinear Control of Mobile Inverted Pendulum: Theory and Experiment
Authors: V. Sankaranarayanan, V. Amrita Sundari, Sunit P. Gopal
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This paper presents the design and implementation of a nonlinear controller for the point to point control of a mobile inverted pendulum (MIP). The controller is designed based on the kinematic model of the MIP to stabilize all the four coordinates. The stability of the closed-loop system is proved using Lyapunov stability theory. The proposed controller is validated through numerical simulations and also implemented in a laboratory prototype. The results are presented to evaluate the performance of the proposed closed loop system.Keywords: mobile inverted pendulum, switched control, nonlinear systems, lyapunov stability
Procedia PDF Downloads 3281891 A Review on Geomembrane Characteristics and Application in Geotechnical Engineering
Authors: Sandra Ghavam Shirazi, Komeil Valipourian, Mohammad Reza Golhashem
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This paper represents the basic idea and mechanisms associated with the durability of geomembranes and discusses the factors influencing the service life and temperature of geomembrane liners. Geomembrane durability is stated as field performance and laboratory test outcomes under various conditions. Due to the high demand of geomembranes as landfill barriers and their crucial role in sensitive projects, sufficient service life of geomembranes is very important, therefore in this paper, the durability, the effect of temperature on geomembrane and the role of this type of reinforcement in different types of soil will be discussed. Also, the role of geomembrane in the earthquake will be considered in the last part of the paper.Keywords: geomembrane, durability temperature soil mechanic, soil
Procedia PDF Downloads 3091890 Quantum Graph Approach for Energy and Information Transfer through Networks of Cables
Authors: Mubarack Ahmed, Gabriele Gradoni, Stephen C. Creagh, Gregor Tanner
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High-frequency cables commonly connect modern devices and sensors. Interestingly, the proportion of electric components is rising fast in an attempt to achieve lighter and greener devices. Modelling the propagation of signals through these cable networks in the presence of parameter uncertainty is a daunting task. In this work, we study the response of high-frequency cable networks using both Transmission Line and Quantum Graph (QG) theories. We have successfully compared the two theories in terms of reflection spectra using measurements on real, lossy cables. We have derived a generalisation of the vertex scattering matrix to include non-uniform networks – networks of cables with different characteristic impedances and propagation constants. The QG model implicitly takes into account the pseudo-chaotic behavior, at the vertices, of the propagating electric signal. We have successfully compared the asymptotic growth of eigenvalues of the Laplacian with the predictions of Weyl law. We investigate the nearest-neighbour level-spacing distribution of the resonances and compare our results with the predictions of Random Matrix Theory (RMT). To achieve this, we will compare our graphs with the generalisation of Wigner distribution for open systems. The problem of scattering from networks of cables can also provide an analogue model for wireless communication in highly reverberant environments. In this context, we provide a preliminary analysis of the statistics of communication capacity for communication across cable networks, whose eventual aim is to enable detailed laboratory testing of information transfer rates using software defined radio. We specialise this analysis in particular for the case of MIMO (Multiple-Input Multiple-Output) protocols. We have successfully validated our QG model with both TL model and laboratory measurements. The growth of Eigenvalues compares well with Weyl’s law and the level-spacing distribution agrees so well RMT predictions. The results we achieved in the MIMO application compares favourably with the prediction of a parallel on-going research (sponsored by NEMF21.)Keywords: eigenvalues, multiple-input multiple-output, quantum graph, random matrix theory, transmission line
Procedia PDF Downloads 1731889 The Use of Venous Glucose, Serum Lactate and Base Deficit as Biochemical Predictors of Mortality in Polytraumatized Patients: Acomparative with Trauma and Injury Severity Score and Acute Physiology and Chronic Health Evalution IV
Authors: Osama Moustafa Zayed
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Aim of the work: To evaluate the effectiveness of venous glucose, levels of serum lactate and base deficit in polytraumatized patients as simple parameters to predict the mortality in these patients. Compared to the predictive value of Trauma and injury severity (TRISS) and Acute Physiology And Chronic Health Evaluation IV (APACHE IV). Introduction: Trauma is a serious global health problem, accounting for approximately one in 10 deaths worldwide. Trauma accounts for 5 million deaths per year. Prediction of mortality in trauma patients is an important part of trauma care. Several trauma scores have been devised to predict injury severity and risk of mortality. The trauma and injury severity score (TRISS) was most common used. Regardless of the accuracy of trauma scores, is based on an anatomical description of every injury and cannot be assigned to the patients until a full diagnostic procedure has been performed. So we hypothesized that alterations in admission glucose, lactate levels and base deficit would be an early and easy rapid predictor of mortality. Patient and Method: a comparative cross-sectional study. 282 Polytraumatized patients attended to the Emergency Department(ED) of the Suez Canal university Hospital constituted. The period from 1/1/2012 to 1/4/2013 was included. Results: We found that the best cut off value of TRISS probability of survival score for prediction of mortality among poly-traumatized patients is = 90, with 77% sensitivity and 89% specificity using area under the ROC curve (0.89) at (95%CI). APACHE IV demonstrated 67% sensitivity and 95% specificity at 95% CI at cut off point 99. The best cutoff value of Random Blood Sugar (RBS) for prediction of mortality was>140 mg/dl, with 89%, sensitivity, 49% specificity. The best cut off value of base deficit for prediction of mortality was less than -5.6 with 64% sensitivity, 93% specificity. The best cutoff point of lactate for prediction of mortality was > 2.6 mmol/L with 92%, sensitivity, 42% specificity. Conclusion: According to our results from all evaluated predictors of mortality (laboratory and scores) and mortality based on the estimated cutoff values using ROC curves analysis, the highest risk of mortality was found using a cutoff value of 90 in TRISS score while with laboratory parameters the highest risk of mortality was with serum lactate > 2.6 . Although that all of the three parameter are accurate in predicting mortality in poly-traumatized patients and near with each other, as in serum lactate the area under the curve 0.82, in BD 0.79 and 0.77 in RBS.Keywords: APACHE IV, emergency department, polytraumatized patients, serum lactate
Procedia PDF Downloads 2941888 Contribution to Experiments of a Free Surface Supercritical Flow over an Uneven Bottom
Authors: M. Bougamouza, M. Bouhadef, T. Zitoun
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The aim of this study is to examine, through experimentation in the laboratory, the supercritical flow in the presence of an obstacle in a rectangular channel. The supercritical regime in the whole hydraulic channel is achieved by adding a convergent. We will observe the influence of the obstacle shape and dimension on the characteristics of the supercritical flow, mainly the free-surface elevation and the velocity profile. The velocity measurements have been conducted with the one dimension laser anemometry technique.Keywords: experiments, free-surface flow, hydraulic channel, uneven bottom, laser anemometry, supercritical regime
Procedia PDF Downloads 2511887 Induced Bone Tissue Temperature in Drilling Procedures: A Comparative Laboratory Study with and without Lubrication
Authors: L. Roseiro, C. Veiga, V. Maranha, A. Neto, N. Laraqi, A. Baïri, N. Alilat
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In orthopedic surgery there are various situations in which the surgeon needs to implement methods of cutting and drilling the bone. With this type of procedure the generated friction leads to a localized increase in temperature, which may lead to the bone necrosis. Recognizing the importance of studying this phenomenon, an experimental evaluation of the temperatures developed during the procedure of drilling bone has been done. Additionally the influence of the use of the procedure with / without additional lubrication during drilling of bone has also been done. The obtained results are presented and discussed and suggests an advantage in using additional lubrication as a way to minimize the appearance of bone tissue necrosis during bone drilling procedures.Keywords: bone necrosis, bone drilling, thermography, surgery
Procedia PDF Downloads 5971886 Laboratory and Numerical Hydraulic Modelling of Annular Pipe Electrocoagulation Reactors
Authors: Alejandra Martin-Dominguez, Javier Canto-Rios, Velitchko Tzatchkov
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Electrocoagulation is a water treatment technology that consists of generating coagulant species in situ by electrolytic oxidation of sacrificial anode materials triggered by electric current. It removes suspended solids, heavy metals, emulsified oils, bacteria, colloidal solids and particles, soluble inorganic pollutants and other contaminants from water, offering an alternative to the use of metal salts or polymers and polyelectrolyte addition for breaking stable emulsions and suspensions. The method essentially consists of passing the water being treated through pairs of consumable conductive metal plates in parallel, which act as monopolar electrodes, commonly known as ‘sacrificial electrodes’. Physicochemical, electrochemical and hydraulic processes are involved in the efficiency of this type of treatment. While the physicochemical and electrochemical aspects of the technology have been extensively studied, little is known about the influence of the hydraulics. However, the hydraulic process is fundamental for the reactions that take place at the electrode boundary layers and for the coagulant mixing. Electrocoagulation reactors can be open (with free water surface) and closed (pressurized). Independently of the type of rector, hydraulic head loss is an important factor for its design. The present work focuses on the study of the total hydraulic head loss and flow velocity and pressure distribution in electrocoagulation reactors with single or multiple concentric annular cross sections. An analysis of the head loss produced by hydraulic wall shear friction and accessories (minor head losses) is presented, and compared to the head loss measured on a semi-pilot scale laboratory model for different flow rates through the reactor. The tests included laminar, transitional and turbulent flow. The observed head loss was compared also to the head loss predicted by several known conceptual theoretical and empirical equations, specific for flow in concentric annular pipes. Four single concentric annular cross section and one multiple concentric annular cross section reactor configuration were studied. The theoretical head loss resulted higher than the observed in the laboratory model in some of the tests, and lower in others of them, depending also on the assumed value for the wall roughness. Most of the theoretical models assume that the fluid elements in all annular sections have the same velocity, and that flow is steady, uniform and one-dimensional, with the same pressure and velocity profiles in all reactor sections. To check the validity of such assumptions, a computational fluid dynamics (CFD) model of the concentric annular pipe reactor was implemented using the ANSYS Fluent software, demonstrating that pressure and flow velocity distribution inside the reactor actually is not uniform. Based on the analysis, the equations that predict better the head loss in single and multiple annular sections were obtained. Other factors that may impact the head loss, such as the generation of coagulants and gases during the electrochemical reaction, the accumulation of hydroxides inside the reactor, and the change of the electrode material with time, are also discussed. The results can be used as tools for design and scale-up of electrocoagulation reactors, to be integrated into new or existing water treatment plants.Keywords: electrocoagulation reactors, hydraulic head loss, concentric annular pipes, computational fluid dynamics model
Procedia PDF Downloads 2181885 Corpora in Secondary Schools Training Courses for English as a Foreign Language Teachers
Authors: Francesca Perri
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This paper describes a proposal for a teachers’ training course, focused on the introduction of corpora in the EFL didactics (English as a foreign language) of some Italian secondary schools. The training course is conceived as a part of a TEDD participant’s five months internship. TEDD (Technologies for Education: diversity and devices) is an advanced course held by the Department of Engineering and Information Technology at the University of Trento, Italy. Its main aim is to train a selected, heterogeneous group of graduates to engage with the complex interdependence between education and technology in modern society. The educational approach draws on a plural coexistence of various theories as well as socio-constructivism, constructionism, project-based learning and connectivism. TEDD educational model stands as the main reference source to the design of a formative course for EFL teachers, drawing on the digitalization of didactics and creation of learning interactive materials for L2 intermediate students. The training course lasts ten hours, organized into five sessions. In the first part (first and second session) a series of guided and semi-guided activities drive participants to familiarize with corpora through the use of a digital tools kit. Then, during the second part, participants are specifically involved in the realization of a ML (Mistakes Laboratory) where they create, develop and share digital activities according to their teaching goals with the use of corpora, supported by the digital facilitator. The training course takes place into an ICT laboratory where the teachers work either individually or in pairs, with a computer connected to a wi-fi connection, while the digital facilitator shares inputs, materials and digital assistance simultaneously on a whiteboard and on a digital platform where participants interact and work together both synchronically and diachronically. The adoption of good ICT practices is a fundamental step to promote the introduction and use of Corpus Linguistics in EFL teaching and learning processes, in fact dealing with corpora not only promotes L2 learners’ critical thinking and orienteering versus wild browsing when they are looking for ready-made translations or language usage samples, but it also entails becoming confident with digital tools and activities. The paper will explain reasons, limits and resources of the pedagogical approach adopted to engage EFL teachers with the use of corpora in their didactics through the promotion of digital practices.Keywords: digital didactics, education, language learning, teacher training
Procedia PDF Downloads 1541884 A Survey of Some Technology Enhanced Teaching and Learning Techniques: Implication to Educational Development in Nigeria
Authors: Abdullahi Bn Umar
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Over the years curriculum planners and researchers in education have continued to seek for ways to improve teaching and learning by way of varying approaches to curriculum and instruction in line with dynamic nature of knowledge. In this regards various innovative strategies to teaching and learning have been adopted to match with the technological advancement in education particularly in the aspect of instructional delivery through Information Communication Technology (ICT) as a tools. This paper reviews some innovative strategies and how they impact on learner’s achievement and educational development in Nigeria. The paper concludes by recommending innovative approach appropriate for use in Nigerian context.Keywords: innovation, instructional delivery, virtual laboratory, educational design
Procedia PDF Downloads 4831883 Fracture Toughness Characterizations of Single Edge Notch (SENB) Testing Using DIC System
Authors: Amr Mohamadien, Ali Imanpour, Sylvester Agbo, Nader Yoosef-Ghodsi, Samer Adeeb
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The fracture toughness resistance curve (e.g., J-R curve and crack tip opening displacement (CTOD) or δ-R curve) is important in facilitating strain-based design and integrity assessment of oil and gas pipelines. This paper aims to present laboratory experimental data to characterize the fracture behavior of pipeline steel. The influential parameters associated with the fracture of API 5L X52 pipeline steel, including different initial crack sizes, were experimentally investigated for a single notch edge bend (SENB). A total of 9 small-scale specimens with different crack length to specimen depth ratios were conducted and tested using single edge notch bending (SENB). ASTM E1820 and BS7448 provide testing procedures to construct the fracture resistance curve (Load-CTOD, CTOD-R, or J-R) from test results. However, these procedures are limited by standard specimens’ dimensions, displacement gauges, and calibration curves. To overcome these limitations, this paper presents the use of small-scale specimens and a 3D-digital image correlation (DIC) system to extract the parameters required for fracture toughness estimation. Fracture resistance curve parameters in terms of crack mouth open displacement (CMOD), crack tip opening displacement (CTOD), and crack growth length (∆a) were carried out from test results by utilizing the DIC system, and an improved regression fitting resistance function (CTOD Vs. crack growth), or (J-integral Vs. crack growth) that is dependent on a variety of initial crack sizes was constructed and presented. The obtained results were compared to the available results of the classical physical measurement techniques, and acceptable matchings were observed. Moreover, a case study was implemented to estimate the maximum strain value that initiates the stable crack growth. This might be of interest to developing more accurate strain-based damage models. The results of laboratory testing in this study offer a valuable database to develop and validate damage models that are able to predict crack propagation of pipeline steel, accounting for the influential parameters associated with fracture toughness.Keywords: fracture toughness, crack propagation in pipeline steels, CTOD-R, strain-based damage model
Procedia PDF Downloads 631882 Practices in Planning, Design and Construction of Head Race Tunnel of a Hydroelectric Project
Authors: M. S. Thakur, Mohit Shukla
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A channel/tunnel, which carries the water to the penstock/pressure shaft is called headrace tunnel (HRT). It is necessary to know the general topography, geology of the area, state of stress and other mechanical properties of the strata. For this certain topographical and geological investigations, in-situ and laboratory tests, and observations are required to be done. These investigations play an important role in a tunnel design as these help in deciding the optimum layout, shape and size and support requirements of the tunnel. The paper includes inputs from Nathpa Jhakri Hydeoelectric project which is India’s highest capacity (1500 MW) operating hydroelectric project. The paper would help the design engineers with various new concepts and preparedness against geological surprises.Keywords: tunnelling, geology, HRT, rockmass
Procedia PDF Downloads 2551881 Pioneer Synthesis and Characterization of Boron Containing Hard Materials
Authors: Gülşah Çelik Gül, Figen Kurtuluş
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The first laboratory synthesis of hard materials such as diamond proceeded to attack of developing materials with high hardness to compete diamond. Boron rich solids are good candidates owing to their short interatomic bond lengths and strong covalent character. Boron containing hard material was synthesized by modified-microwave method under nitrogen atmosphere by using a fuel (glycine or urea), amorphous boron and/or boric acid in appropriate molar ratio. Characterizations were done by x-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy/energy dispersive analyze (SEM/EDS), thermo gravimetric/differantial thermal analysis (TG/DTA).Keywords: boron containing materials, hard materials, microwave synthesis, powder X-ray diffraction
Procedia PDF Downloads 593