Search results for: black box testing
2813 Biomechanical Assessment of Esophageal Elongation
Authors: Marta Kozuń, Krystian Toczewski, Sylwester Gerus, Justyna Wolicka, Kamila Boberek, Jarosław Filipiak, Dariusz Patkowski
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Long gap esophageal atresia is a congenital defect and is a challenge for pediatric surgeons all over the world. There are different surgical techniques in use to treat atresia. One of them is esophageal elongation but the optimal suture placement technique to achieve maximum elongation with low-risk complications is still unknown. The aim of the study was to characterize the process of esophageal elongation from the biomechanical point of view. Esophagi of white Pekin Duck was used as a model based on the size of this animal which is similar to a newborn (2.5-4kg). The specimens were divided into two groups: the control group (CG) and the group with sutures (SG). The esophagi of the control group were mounted in the grips of the MTS Tytron 250 testing machine and tensile test until rupture was performed. The loading speed during the test was 10mm/min. Then the SG group was tested. Each esophagus was cut into two equal parts and that were fused together using surgical sutures. The distance between both esophagus parts was 20mm. Ten both ends were mounted on the same testing machine and the tensile test with the same parameters was conducted. For all specimens, force and elongation were recorded. The biomechanical properties, i.e., the maximal force and maximal elongation, were determined on the basis of force-elongation curves. The maximal elongation was determined at the point of maximal force. The force achieved with the suture group was 10.1N±1.9N and 50.3N±11.6N for the control group. The highest elongation was also obtained for the control group: 18mm±3mm vs. 13.5mm ±2.4mm for the suture group. The presented study expands the knowledge of elongation of esophagi. It is worth emphasizing that the duck esophagus differs from the esophagus of a newborn, i.e., its wall lacks striated muscle cells. This is why the parts of animal esophagi used in the research are may characterized by different biomechanical properties in comparison with newborn tissue.Keywords: long gap atresia treatment, esophageal elongation, biomechanical properties, soft tissue
Procedia PDF Downloads 922812 Application of a Model-Free Artificial Neural Networks Approach for Structural Health Monitoring of the Old Lidingö Bridge
Authors: Ana Neves, John Leander, Ignacio Gonzalez, Raid Karoumi
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Systematic monitoring and inspection are needed to assess the present state of a structure and predict its future condition. If an irregularity is noticed, repair actions may take place and the adequate intervention will most probably reduce the future costs with maintenance, minimize downtime and increase safety by avoiding the failure of the structure as a whole or of one of its structural parts. For this to be possible decisions must be made at the right time, which implies using systems that can detect abnormalities in their early stage. In this sense, Structural Health Monitoring (SHM) is seen as an effective tool for improving the safety and reliability of infrastructures. This paper explores the decision-making problem in SHM regarding the maintenance of civil engineering structures. The aim is to assess the present condition of a bridge based exclusively on measurements using the suggested method in this paper, such that action is taken coherently with the information made available by the monitoring system. Artificial Neural Networks are trained and their ability to predict structural behavior is evaluated in the light of a case study where acceleration measurements are acquired from a bridge located in Stockholm, Sweden. This relatively old bridge is presently still in operation despite experiencing obvious problems already reported in previous inspections. The prediction errors provide a measure of the accuracy of the algorithm and are subjected to further investigation, which comprises concepts like clustering analysis and statistical hypothesis testing. These enable to interpret the obtained prediction errors, draw conclusions about the state of the structure and thus support decision making regarding its maintenance.Keywords: artificial neural networks, clustering analysis, model-free damage detection, statistical hypothesis testing, structural health monitoring
Procedia PDF Downloads 1962811 Static Application Security Testing Approach for Non-Standard Smart Contracts
Authors: Antonio Horta, Renato Marinho, Raimir Holanda
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Considered as an evolution of the Blockchain, the Ethereum platform, besides allowing transactions of its cryptocurrency named Ether, it allows the programming of decentralised applications (DApps) and smart contracts. However, this functionality into blockchains has raised other types of threats, and the exploitation of smart contracts vulnerabilities has taken companies to experience big losses. This research intends to figure out the number of contracts that are under risk of being drained. Through a deep investigation, more than two hundred thousand smart contracts currently available in the Ethereum platform were scanned and estimated how much money is at risk. The experiment was based in a query run on Google Big Query in July 2022 and returned 50,707,133 contracts published on the Ethereum platform. After applying the filtering criteria, the experimentgot 430,584 smart contracts to download and analyse. The filtering criteria consisted of filtering out: ERC20 and ERC721 contracts, contracts without transactions, and contracts without balance. From this amount of 430,584 smart contracts selected, only 268,103 had source codes published on Etherscan, however, we discovered, using a hashing process, that there were contracts duplication. Removing the duplicated contracts, the process ended up with 20,417 source codes, which were analysed using the open source SAST tool smartbugswith oyente and securify algorithms. In the end, there was nearly $100,000 at risk of being drained from the potentially vulnerable smart contracts. It is important to note that the tools used in this study may generate false positives, which may interfere with the number of vulnerable contracts. To address this point, our next step in this research is to develop an application to test the contract in a parallel environment to verify the vulnerability. Finally, this study aims to alert users and companies about the risk on not properly creating and analysing their smart contracts before publishing them into the platform. As any other application, smart contracts are at risk of having vulnerabilities which, in this case, may result in direct financial losses.Keywords: blockchain, reentrancy, static application security testing, smart contracts
Procedia PDF Downloads 812810 Dynamic Test for Stability of Columns in Sway Mode
Authors: Elia Efraim, Boris Blostotsky
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Testing of columns in sway mode is performed in order to determine the maximal allowable load limited by plastic deformations or their end connections and a critical load limited by columns stability. Motivation to determine accurate value of critical force is caused by its using as follow: - critical load is maximal allowable load for given column configuration and can be used as criterion of perfection; - it is used in calculation prescribed by standards for design of structural elements under combined action of compression and bending; - it is used for verification of theoretical analysis of stability at various end conditions of columns. In the present work a new non-destructive method for determination of columns critical buckling load in sway mode is proposed. The method allows performing measurements during the tests under loads that exceeds the columns critical load without losing its stability. The possibility of such loading is achieved by structure of the loading system. The system is performed as frame with rigid girder, one of the columns is the tested column and the other is additional two-hinged strut. Loading of the frame is carried out by the flexible traction element attached to the girder. The load applied on the tested column can achieve values that exceed the critical load by choice of parameters of the traction element and the additional strut. The system lateral stiffness and the column critical load are obtained by the dynamic method. The experiment planning and the comparison between the experimental and theoretical values were performed based on the developed dependency of lateral stiffness of the system on vertical load, taking into account semi-rigid connections of the column's ends. The agreement between the obtained results was established. The method can be used for testing of real full-size columns in industrial conditions.Keywords: buckling, columns, dynamic method, end-fixity factor, sway mode
Procedia PDF Downloads 3442809 Evaluation of the Improve Vacuum Blood Collection Tube for Laboratory Tests
Authors: Yoon Kyung Song, Seung Won Han, Sang Hyun Hwang, Do Hoon Lee
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Laboratory tests is a significant part for the diagnosis, prognosis, treatment of diseases. Blood collection is a simple process, but can be a potential cause of pre-analytical errors. Vacuum blood collection tubes used to collect and store the blood specimens is necessary for accurate test results. The purpose of this study was to validate Improve serum separator tube(SST) (Guanzhou Improve Medical Instruments Co., Ltd, China) for routine clinical chemistry laboratory testing. Blood specimens were collected from 100 volunteers in three different serum vacuum tubes (Greiner SST , Becton Dickinson SST , Improve SST). The specimens were evaluated for 16 routine chemistry tests using TBA-200FR NEO (Toshiba Medical Co. JAPAN). The results were statistically analyzed by paired t-test and Bland-Altman plot. For stability test, the initial results for each tube were compared with results of 72 hours preserved specimens. Their clinical availability was evaluated by biological Variation of Ricos data bank. Paired t-test analysis revealed that AST, ALT, K, Cl showed statistically same results but calcium (CA), phosphorus(PHOS), glucose(GLU), BUN, uric acid(UA), cholesterol(CHOL), total protein(TP), albumin(ALB), total bilirubin(TB), ALP, creatinine(CRE), sodium(NA) were different(P < 0.05) between Improve SST and Greiner SST. Also, CA, PHOS, TP, TB, AST, ALT, NA, K, Cl showed statistically the same results but GLU, BUN, UA, CHOL, ALB, ALP, CRE were different between Improve SST and Becton Dickinson SST. All statistically different cases were clinically acceptable by biological Variation of Ricos data bank. Improve SST tubes showed satisfactory results compared with Greiner SST and Becton Dickinson SST. We concluded that the tubes are acceptable for routine clinical chemistry laboratory testing.Keywords: blood collection, Guanzhou Improve, SST, vacuum tube
Procedia PDF Downloads 2342808 Fe Modified Tin Oxide Thin Film Based Matrix for Reagentless Uric Acid Biosensing
Authors: Kashima Arora, Monika Tomar, Vinay Gupta
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Biosensors have found potential applications ranging from environmental testing and biowarfare agent detection to clinical testing, health care, and cell analysis. This is driven in part by the desire to decrease the cost of health care and to obtain precise information more quickly about the health status of patient by the development of various biosensors, which has become increasingly prevalent in clinical testing and point of care testing for a wide range of biological elements. Uric acid is an important byproduct in human body and a number of pathological disorders are related to its high concentration in human body. In past few years, rapid growth in the development of new materials and improvements in sensing techniques have led to the evolution of advanced biosensors. In this context, metal oxide thin film based matrices due to their bio compatible nature, strong adsorption ability, high isoelectric point (IEP) and abundance in nature have become the materials of choice for recent technological advances in biotechnology. In the past few years, wide band-gap metal oxide semiconductors including ZnO, SnO₂ and CeO₂ have gained much attention as a matrix for immobilization of various biomolecules. Tin oxide (SnO₂), wide band gap semiconductor (Eg =3.87 eV), despite having multifunctional properties for broad range of applications including transparent electronics, gas sensors, acoustic devices, UV photodetectors, etc., it has not been explored much for biosensing purpose. To realize a high performance miniaturized biomolecular electronic device, rf sputtering technique is considered to be the most promising for the reproducible growth of good quality thin films, controlled surface morphology and desired film crystallization with improved electron transfer property. Recently, iron oxide and its composites have been widely used as matrix for biosensing application which exploits the electron communication feature of Fe, for the detection of various analytes using urea, hemoglobin, glucose, phenol, L-lactate, H₂O₂, etc. However, to the authors’ knowledge, no work is being reported on modifying the electronic properties of SnO₂ by implanting with suitable metal (Fe) to induce the redox couple in it and utilizing it for reagentless detection of uric acid. In present study, Fe implanted SnO₂ based matrix has been utilized for reagentless uric acid biosensor. Implantation of Fe into SnO₂ matrix is confirmed by energy-dispersive X-Ray spectroscopy (EDX) analysis. Electrochemical techniques have been used to study the response characteristics of Fe modified SnO₂ matrix before and after uricase immobilization. The developed uric acid biosensor exhibits a high sensitivity to about 0.21 mA/mM and a linear variation in current response over concentration range from 0.05 to 1.0 mM of uric acid besides high shelf life (~20 weeks). The Michaelis-Menten kinetic parameter (Km) is found to be relatively very low (0.23 mM), which indicates high affinity of the fabricated bioelectrode towards uric acid (analyte). Also, the presence of other interferents present in human serum has negligible effect on the performance of biosensor. Hence, obtained results highlight the importance of implanted Fe:SnO₂ thin film as an attractive matrix for realization of reagentless biosensors towards uric acid.Keywords: Fe implanted tin oxide, reagentless uric acid biosensor, rf sputtering, thin film
Procedia PDF Downloads 1712807 Role of Physical Appearance in Associating People with a Group Identity
Authors: Gurleen Kaur
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Being tall-short, fat-thin, black-white, etc. is an inevitable part of how people perceive you. This association of people with your external appearance carves out an identity for you. This paper will look at the reasons why people relate a person to a particular categorization on the basis of his/her physical appearance. The paper delves into reasons for this categorization into groups: Subconscious grouping, personal gain, ease of relating to the group, and social acceptance. Development of certain unique physical features also leads to a person relating himself to a collective identity. Thus, this paper will support the fact that physical appearance plays a crucial role in categorization of people into groups and hence forming a group identity for them. This paper is divided into three parts. The first part will discuss what physical appearance is and how is it linked to our daily lives. The second part will talk about why it works i.e. why this factor of external appearance is important in formation of identity. The last part will talk about the factors which lead to categorization of identity because of physical appearance.Keywords: group identity, physical appearance, subconscious grouping, collective identity
Procedia PDF Downloads 4132806 Homosexuality and Inclusion: Experiences of Learners and Teachers within South African School's Contex
Authors: Tsediso Makoelle
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South Africa like in other parts of the world has acknowledged the prevalence of the phenomenon of homosexuality in the society. Due to the number of homosexuality cases in the South African society, questions have been asked about the impact of homosexuality in schools and how teachers and learners deal with homosexuality within the context of an emerging inclusive education system. This qualitative study analysis the experiences of teachers and learners in selected secondary schools in relation to prevalence of transgender in schools. Interviews were conducted with principals, teachers and focus group of learners in schools were cases homosexuality have been reported. Data was analysed using an inductive analysis framework. Among the findings was that homosexuality is still viewed as a taboo in Black-African dominated school communities and that the need to create all-embracing and inclusive environment was evident. The study suggests a needs to open communications in communities about homosexuality in order to develop an all-inclusive environment for all learners regardless of their sexual orientation.Keywords: homosexuality, inclusive education, sexual orientation, transgender
Procedia PDF Downloads 2382805 Testing for Endogeneity of Foreign Direct Investment: Implications for Economic Policy
Authors: Liwiusz Wojciechowski
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Research background: The current knowledge does not give a clear answer to the question of the impact of FDI on productivity. Results of the empirical studies are still inconclusive, no matter how extensive and diverse in terms of research approaches or groups of countries analyzed they are. It should also take into account the possibility that FDI and productivity are linked and that there is a bidirectional relationship between them. This issue is particularly important because on one hand FDI can contribute to changes in productivity in the host country, but on the other hand its level and dynamics may imply that FDI should be undertaken in a given country. As already mentioned, a two-way relationship between the presence of foreign capital and productivity in the host country should be assumed, taking into consideration the endogenous nature of FDI. Purpose of the article: The overall objective of this study is to determine the causality between foreign direct investment and total factor productivity in host county in terms of different relative absorptive capacity across countries. In the classic sense causality among variables is not always obvious and requires for testing, which would facilitate proper specification of FDI models. The aim of this article is to study endogeneity of selected macroeconomic variables commonly being used in FDI models in case of Visegrad countries: main recipients of FDI in CEE. The findings may be helpful in determining the structure of the actual relationship between variables, in appropriate models estimation and in forecasting as well as economic policymaking. Methodology/methods: Panel and time-series data techniques including GMM estimator, VEC models and causality tests were utilized in this study. Findings & Value added: The obtained results allow to confirm the hypothesis states the bi-directional causality between FDI and total factor productivity. Although results differ from among countries and data level of aggregation implications may be useful for policymakers in case of providing foreign capital attracting policy.Keywords: endogeneity, foreign direct investment, multi-equation models, total factor productivity
Procedia PDF Downloads 1912804 [Keynote] Implementation of Quality Control Procedures in Radiotherapy CT Simulator
Authors: B. Petrović, L. Rutonjski, M. Baucal, M. Teodorović, O. Čudić, B. Basarić
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Purpose/Objective: Radiotherapy treatment planning requires use of CT simulator, in order to acquire CT images. The overall performance of CT simulator determines the quality of radiotherapy treatment plan, and at the end, the outcome of treatment for every single patient. Therefore, it is strongly advised by international recommendations, to set up a quality control procedures for every machine involved in radiotherapy treatment planning process, including the CT scanner/ simulator. The overall process requires number of tests, which are used on daily, weekly, monthly or yearly basis, depending on the feature tested. Materials/Methods: Two phantoms were used: a dedicated phantom CIRS 062QA, and a QA phantom obtained with the CT simulator. The examined CT simulator was Siemens Somatom Definition as Open, dedicated for radiation therapy treatment planning. The CT simulator has a built in software, which enables fast and simple evaluation of CT QA parameters, using the phantom provided with the CT simulator. On the other hand, recommendations contain additional test, which were done with the CIRS phantom. Also, legislation on ionizing radiation protection requires CT testing in defined periods of time. Taking into account the requirements of law, built in tests of a CT simulator, and international recommendations, the intitutional QC programme for CT imulator is defined, and implemented. Results: The CT simulator parameters evaluated through the study were following: CT number accuracy, field uniformity, complete CT to ED conversion curve, spatial and contrast resolution, image noise, slice thickness, and patient table stability.The following limits are established and implemented: CT number accuracy limits are +/- 5 HU of the value at the comissioning. Field uniformity: +/- 10 HU in selected ROIs. Complete CT to ED curve for each tube voltage must comply with the curve obtained at comissioning, with deviations of not more than 5%. Spatial and contrast resultion tests must comply with the tests obtained at comissioning, otherwise machine requires service. Result of image noise test must fall within the limit of 20% difference of the base value. Slice thickness must meet manufacturer specifications, and patient stability with longitudinal transfer of loaded table must not differ of more than 2mm vertical deviation. Conclusion: The implemented QA tests gave overall basic understanding of CT simulator functionality and its clinical effectiveness in radiation treatment planning. The legal requirement to the clinic is to set up it’s own QA programme, with minimum testing, but it remains user’s decision whether additional testing, as recommended by international organizations, will be implemented, so to improve the overall quality of radiation treatment planning procedure, as the CT image quality used for radiation treatment planning, influences the delineation of a tumor and calculation accuracy of treatment planning system, and finally delivery of radiation treatment to a patient.Keywords: CT simulator, radiotherapy, quality control, QA programme
Procedia PDF Downloads 5212803 Investigation of Self-Assembling of Maghemite Nanoparticles into Chain–Like Structures Using Birefringence Measurements
Authors: C. R. Stein; K. Skeff Neto, K. L. C. Miranda, P. P. C. Sartoratto, M. E. Xavier, Z. G. M. Lacava, S. M. De Freita, P. C. Morais
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In this study, static magnetic birefringence (SMB) and transmission electron microscopy (TEM) were used to investigate the self-assembling of maghemite nanoparticles suspended as biocompatible magnetic fluid (BMF) while incubated or not with the Black Eyed–Pea Trypsin Chymotripsin Inhibitor–BTCI protein. The stock samples herein studied are dextran coated maghemite nanoparticles (average core diameter of 7.1 nm, diameter dispersion of 0.26, and containing 4.6×1016 particle/mL) and the dextran coated maghemite nanoparticles associated with the BTCI protein. Several samples were prepared by diluting the stock samples with deionized water while following their colloidal stability. The diluted samples were investigated using SMB measurements to assess the average sizes of the self-assembled and suspended mesoscopic structures whereas the TEM micrographs provide the morphology of the as-suspended units. The SMB data were analyzed using a model that includes the particle-particle interaction within the mean field model picture.Keywords: biocompatible magnetic fluid, maghemite nanoparticles, self-assembling
Procedia PDF Downloads 4712802 Supporting a Moral Growth Mindset Among College Students
Authors: Kate Allman, Heather Maranges, Elise Dykhuis
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Moral Growth Mindset (MGM) is the belief that one has the capacity to become a more moral person, as opposed to a fixed conception of one’s moral ability and capacity (Han et al., 2018). Building from Dweck’s work in incremental implicit theories of intelligence (2008), Moral Growth Mindset (Han et al., 2020) extends growth mindsets into the moral dimension. The concept of MGM has the potential to help researchers understand how both mindsets and interventions can impact character development, and it has even been shown to have connections to voluntary service engagement (Han et al., 2018). Understanding the contexts in which MGM might be cultivated could help to promote the further cultivation of character, in addition to prosocial behaviors like service engagement, which may, in turn, promote larger scale engagement in social justice-oriented thoughts, feelings, and behaviors. In particular, college may be a place to intentionally cultivate a growth mindset toward moral capacities, given the unique developmental and maturational components of the college experience, including contextual opportunity (Lapsley & Narvaez, 2006) and independence requiring the constant consideration, revision, and internalization of personal values (Lapsley & Woodbury, 2016). In a semester-long, quasi-experimental study, we examined the impact of a pedagogical approach designed to cultivate college student character development on participants’ MGM. With an intervention (n=69) and a control group (n=97; Pre-course: 27% Men; 66% Women; 68% White; 18% Asian; 2% Black; <1% Hispanic/Latino), we investigated whether college courses that intentionally incorporate character education pedagogy (Lamb, Brant, Brooks, 2021) affect a variety of psychosocial variables associated with moral thoughts, feelings, identity, and behavior (e.g. moral growth mindset, honesty, compassion, etc.). The intervention group consisted of 69 undergraduate students (Pre-course: 40% Men; 52% Women; 68% White; 10.5% Black; 7.4% Asian; 4.2% Hispanic/Latino) that voluntarily enrolled in five undergraduate courses that encouraged students to engage with key concepts and methods of character development through the application of research-based strategies and personal reflection on goals and experiences. Moral Growth Mindset was measured using the four-item Moral Growth Mindset scale (Han et al., 2020), with items such as You can improve your basic morals and character considerably on a six-point Likert scale from 1 (strongly disagree) to 6 (strongly agree). Higher scores of MGM indicate a stronger belief that one can become a more moral person with personal effort. Reliability at Time 1 was Cronbach’s ɑ= .833, and at Time 2 Cronbach’s ɑ= .772. An Analysis of Covariance (ANCOVA) was conducted to explore whether post-course MGM scores were different between the intervention and control when controlling for pre-course MGM scores. The ANCOVA indicated significant differences in MGM between groups post-course, F(1,163) = 8.073, p = .005, R² = .11, where descriptive statistics indicate that intervention scores were higher than the control group at post-course. Results indicate that intentional character development pedagogy can be leveraged to support the development of Moral Growth Mindset and related capacities in undergraduate settings.Keywords: moral personality, character education, incremental theories of personality, growth mindset
Procedia PDF Downloads 1352801 The Acceptable Roles of Artificial Intelligence in the Judicial Reasoning Process
Authors: Sonia Anand Knowlton
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There are some cases where we as a society feel deeply uncomfortable with the use of Artificial Intelligence (AI) tools in the judicial decision-making process, and justifiably so. A perfect example is COMPAS, an algorithmic model that predicts recidivism rates of offenders to assist in the determination of their bail conditions. COMPAS turned out to be extremely racist: it massively overpredicted recidivism rates of Black offenders and underpredicted recidivism rates of white offenders. At the same time, there are certain uses of AI in the judicial decision-making process that many would feel more comfortable with and even support. Take, for example, a “super-breathalyzer,” an (albeit imaginary) tool that uses AI to deliver highly detailed information about the subject of the breathalyzer test to the legal decision-makers analyzing their drunk-driving case. This article evaluates the point at which a judge’s use of AI tools begins to undermine the public’s trust in the administration of justice. It argues that the answer to this question depends on whether the AI tool is in a role in which it must perform a moral evaluation of a human being.Keywords: artificial intelligence, judicial reasoning, morality, technology, algorithm
Procedia PDF Downloads 682800 A Thermal Analysis Based Approach to Obtain High Carbonaceous Fibers from Chicken Feathers
Authors: Y. Okumuş, A. Tuna, A. T. Seyhan, H. Çelebi
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Useful carbon fibers were derived from chicken feathers (PCFs) based on a two-step pyrolysis method. The collected PCFs were cleaned and categorized as black, white and brown. Differential scanning calorimeter (DSC) and thermo-gravimetric analyzer (TGA) were systemically used to design the pyrolysis steps. Depending on colors, feathers exhibit different glass transition (Tg) temperatures. Long-time heat treatment applied to the feathers emerged influential on the surface quality of the resulting carbon fibers. Fourier Transformation Infrared (FTIR) examination revealed that the extent of disulfide bond cleavage is highly associated with the feather melting stability. Scanning electron microscopy (SEM) examinations were employed to evaluate the morphological changes of feathers after pyrolysis. Of all, brown feathers were found to be the most promising to turn into useful carbon fibers without any trace of melting and shape distortion when pyrolysis was carried out at 230°C for 24 hours and at 450°C for 1 hour.Keywords: poultry chicken feather, keratin protein fiber, pyrolysis, high carbonaceous fibers
Procedia PDF Downloads 3192799 Dynamic Test for Sway-Mode Buckling of Columns
Authors: Boris Blostotsky, Elia Efraim
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Testing of columns in sway mode is performed in order to determine the maximal allowable load limited by plastic deformations or their end connections and a critical load limited by columns stability. Motivation to determine accurate value of critical force is caused by its using as follow: - critical load is maximal allowable load for given column configuration and can be used as criterion of perfection; - it is used in calculation prescribed by standards for design of structural elements under combined action of compression and bending; - it is used for verification of theoretical analysis of stability at various end conditions of columns. In the present work a new non-destructive method for determination of columns critical buckling load in sway mode is proposed. The method allows performing measurements during the tests under loads that exceeds the columns critical load without losing its stability. The possibility of such loading is achieved by structure of the loading system. The system is performed as frame with rigid girder, one of the columns is the tested column and the other is additional two-hinged strut. Loading of the frame is carried out by the flexible traction element attached to the girder. The load applied on the tested column can achieve a values that exceed the critical load by choice of parameters of the traction element and the additional strut. The system lateral stiffness and the column critical load are obtained by the dynamic method. The experiment planning and the comparison between the experimental and theoretical values were performed based on the developed dependency of lateral stiffness of the system on vertical load, taking into account a semi-rigid connections of the column's ends. The agreement between the obtained results was established. The method can be used for testing of real full-size columns in industrial conditions.Keywords: buckling, columns, dynamic method, semi-rigid connections, sway mode
Procedia PDF Downloads 3052798 Proximate and Amino Acid Composition of Amaranthus hybridus (Spinach), Celosia argentea (Cock's Comb) and Solanum nigrum (Black nightshade)
Authors: S. O. Oladeji, I. Saleh, A. U. Adamu, S. A. Fowotade
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The proximate composition, trace metal level and amino acid composition of Amaranthus hybridus, Celosia argentea and Solanum nigrum were determined. These vegetables were high in their ash contents. Twelve elements were determined: calcium, chromium, copper, iron, lead, magnesium, nickel, phosphorous, potassium, sodium and zinc using flame photometer, atomic absorption and UV-Visible spectrophotometers. Calcium levels were highest ranged between 145.28±0.38 to 235.62±0.41mg/100g in all the samples followed by phosphorus. Quantitative chromatographic analysis of the vegetables hydrolysates revealed seventeen amino acids with concentration of leucine (6.51 to 6.66±0.21g/16gN) doubling that of isoleucine (2.99 to 3.33±0.21g/16gN) in all the samples while the limiting amino acids were cystine and methionine. The result showed that these vegetables were of high nutritive values and could be adequate used as supplement in diet.Keywords: proximate, amino acids, Amaranthus hybridus, Celosia argentea, Solanum nigrum
Procedia PDF Downloads 3922797 The Effectiveness of the South African Government Theory of Expanded Public Works Program: Infrastructure
Authors: Siziwe Monica Zuma
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The Expanded Public Works Program (EPWP) is an instrument that the South African Government uses to reduce unemployment and poverty and also stimulate economic growth. However, due to the limited budget and programs in the EPWP, the program has had challenges in reducing unemployment, poverty and stimulating economic growth. The EPWP Vuk’uphile program had positive outcomes in developing Black emerging contractors, in order for them to participate in the main stream economy far better than when the EPWP program was not introduced. The Skills component of the program particularly the EPWP Infrastructure, which is the most funded program under EPWP has had limited success in transferring appropriate skills to ensure labour participants can penetrate the labour market after participating in the EPWP. Education and skills are important attributes that can contribute to labour absorption, however, the EPWP particularly the infrastructure program needs to strengthen skills development over a longer period of time suggested a year with multi skills relevant to the labour market. Longer and more sustained employment provides a safety net and reduces poverty better that short term employment. The EPWP program can be expanded in the infrastructure sector, focusing on rural infrastructure, agricultural infrastructure, infrastructure related components like property, ownership, management, and other services. These can stimulate the Economic sector Infrastructure of EPWP, offer longer term and more sustained employment and rural enterprise development and further employment. The Expanded Public Works Program (EPWP) is an instrument that the South African Government uses to reduce unemployment and poverty and also stimulate economic growth. However, due to the limited budget and programs in the EPWP, the program has had challenges in reducing unemployment, poverty and stimulating economic growth. The EPWP Vuk’uphile program has had positive outcomes in developing Black emerging contractors, in order for them to participate in the main stream economy far better than when the EPWP program was not introduced. The Skills component of the program particularly the EPWP Infrastructure, which is the most funded program under EPWP has had limited success in transferring appropriate skills to ensure labour participants are able to penetrate the labour market after participating in the EPWP. Education and skills are important attributes that can contribute to labour absorption, however, the EPWP particularly the infrastructure program needs to strengthen skills development over a longer period of time suggested a year with multi skills relevant to the labour market. Longer and more sustained employment provides a safety net and reduces poverty better that short term employment. The EPWP program can be expanded in the infrastructure sector, focusing on rural infrastructure, agricultural infrastructure, infrastructure related components like property, ownership, management, and other services. These can stimulate the Economic sector Infrastructure of EPWP, offer longer term and more sustained employment and rural enterprise development and further employment.Keywords: Expanded Public Works Program (EPWP), VUKÚPHILE, youth, Public Works Programs (PWP), Infrastructure Sector of EPWP (EPWP Infrastructure)
Procedia PDF Downloads 2082796 Characterization of Shorebird Populations in the Algerian Coast
Authors: Imad Eddine Rezouani, Khalil Draidi, Badis bakhouche, Selman Anes Chabani
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The Algerian coast is an important site for wintering and migratory birds. Four species of shorebirds were surveyed, including Kentish plover Charadrius alexandrinus, Little ringed plover Charadrius dubius, Common ringed plover Charadrius hiaticula, and black-winged stilt Himantopus hilarious in three different sites, two important wetlands: Reghaia lake and Macta and a small area Sublette promenade to provide a new data about time activity budget. The study found a higher frequency of abundance in April during the study period (February to May), with a mean of 49. Estimating the temporal activity budget of these coastal birds, it was found that there were three main activities in different proportions between males and females: Pecking (29.51 %) for males, (26.59%) for females, Looking above (28.01%) for males, (19.54 %) for females And Away (9.95%) for males, (11.75%), contrarily the two previous one. Differences between study areas revealed differences in species behavior and distribution.Keywords: wetland, behavioral, algerian coast, shorebirds, time budget activity
Procedia PDF Downloads 522795 Reactivation of Hydrated Cement and Recycled Concrete Powder by Thermal Treatment for Partial Replacement of Virgin Cement
Authors: Gustave Semugaza, Anne Zora Gierth, Tommy Mielke, Marianela Escobar Castillo, Nat Doru C. Lupascu
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The generation of Construction and Demolition Waste (CDW) has globally increased enormously due to the enhanced need in construction, renovation, and demolition of construction structures. Several studies investigated the use of CDW materials in the production of new concrete and indicated the lower mechanical properties of the resulting concrete. Many other researchers considered the possibility of using the Hydrated Cement Powder (HCP) to replace a part of Ordinary Portland Cement (OPC), but only very few investigated the use of Recycled Concrete Powder (RCP) from CDW. The partial replacement of OPC for making new concrete intends to decrease the CO₂ emissions associated with OPC production. However, the RCP and HCP need treatment to produce the new concrete of required mechanical properties. The thermal treatment method has proven to improve HCP properties before their use. Previous research has stated that for using HCP in concrete, the optimum results are achievable by heating HCP between 400°C and 800°C. The optimum heating temperature depends on the type of cement used to make the Hydrated Cement Specimens (HCS), the crushing and heating method of HCP, and the curing method of the Rehydrated Cement Specimens (RCS). This research assessed the quality of recycled materials by using different techniques such as X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC) and thermogravimetry (TG), Scanning electron Microscopy (SEM), and X-ray Fluorescence (XRF). These recycled materials were thermally pretreated at different temperatures from 200°C to 1000°C. Additionally, the research investigated to what extent the thermally treated recycled cement could partially replace the OPC and if the new concrete produced would achieve the required mechanical properties. The mechanical properties were evaluated on the RCS, obtained by mixing the Dehydrated Cement Powder and Recycled Powder (DCP and DRP) with water (w/c = 0.6 and w/c = 0.45). The research used the compressive testing machine for compressive strength testing, and the three-point bending test was used to assess the flexural strength.Keywords: hydrated cement powder, dehydrated cement powder, recycled concrete powder, thermal treatment, reactivation, mechanical performance
Procedia PDF Downloads 1402794 Computational Material Modeling for Mechanical Properties Prediction of Nanoscale Carbon Based Cementitious Materials
Authors: Maryam Kiani, Abdul Basit Kiani
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At larger scales, the performance of cementitious materials is impacted by processes occurring at the nanometer scale. These materials boast intricate hierarchical structures with random features that span from the nanometer to millimeter scale. It is fascinating to observe how the nanoscale processes influence the overall behavior and characteristics of these materials. By delving into and manipulating these processes, scientists and engineers can unlock the potential to create more durable and sustainable infrastructure and construction materials. It's like unraveling a hidden tapestry of secrets that hold the key to building stronger and more resilient structures. The present work employs simulations as the computational modeling methodology to predict mechanical properties for carbon/silica based cementitious materials at the molecular/nano scale level. Studies focused on understanding the effect of higher mechanical properties of cementitious materials with carbon silica nanoparticles via Material Studio materials modeling.Keywords: nanomaterials, SiO₂, carbon black, mechanical properties
Procedia PDF Downloads 1272793 Prediction Study of a Corroded Pressure Vessel Using Evaluation Measurements and Finite Element Analysis
Authors: Ganbat Danaa, Chuluundorj Puntsag
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The steel structures of the Oyu-Tolgoi mining Concentrator plant are corroded during operation, which raises doubts about the continued use of some important structures of the plant, which is one of the problems facing the plant's regular operation. As a part of the main operation of the plant, the bottom part of the pressure vessel, which plays an important role in the reliable operation of the concentrate filter-drying unit, was heavily corroded, so it was necessary to study by engineering calculations, modeling, and simulation using modern advanced engineering programs and methods. The purpose of this research is to investigate whether the corroded part of the pressure vessel can be used normally in the future using advanced engineering software and to predetermine the remaining life of the time of the pressure vessel based on engineering calculations. When the thickness of the bottom part of the pressure vessel was thinned by 0.5mm due to corrosion detected by non-destructive testing, finite element analysis using ANSYS WorkBench software was used to determine the mechanical stress, strain and safety factor in the wall and bottom of the pressure vessel operating under 2.2 MPa working pressure, made conclusions on whether it can be used in the future. According to the recommendations, by using sand-blast cleaning and anti-corrosion paint, the normal, continuous and reliable operation of the Concentrator plant can be ensured, such as ordering new pressure vessels and reducing the installation period. By completing this research work, it will be used as a benchmark for assessing the corrosion condition of steel parts of pressure vessels and other metallic and non-metallic structures operating under severe conditions of corrosion, static and dynamic loads, and other deformed steels to make analysis of the structures and make it possible to evaluate and control the integrity and reliable operation of the structures.Keywords: corrosion, non-destructive testing, finite element analysis, safety factor, structural reliability
Procedia PDF Downloads 512792 Using Industrial Service Quality to Assess Service Quality Perception in Television Advertisement: A Case Study
Authors: Ana L. Martins, Rita S. Saraiva, João C. Ferreira
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Much effort has been placed on the assessment of perceived service quality. Several models can be found in literature, but these are mainly focused on business-to-consumer (B2C) relationships. Literature on how to assess perceived quality in business-to-business (B2B) contexts is scarce both conceptually and in terms of its application. This research aims at filling this gap in literature by applying INDSERV to a case study situation. Under this scope, this research aims at analyzing the adequacy of the proposed assessment tool to other context besides the one where it was developed and by doing so analyzing the perceive quality of the advertisement service provided by a specific television network to its B2B customers. The INDSERV scale was adopted and applied to a sample of 33 clients, via questionnaires adapted to interviews. Data was collected in person or phone. Both quantitative and qualitative data collection was performed. Qualitative data analysis followed content analysis protocol. Quantitative analysis used hypotheses testing. Findings allowed to conclude that the perceived quality of the television service provided by television network is very positive, being the Soft Process Quality the parameter that reveals the highest perceived quality of the service as opposed to Potential Quality. To this end, some comments and suggestions were made by the clients regarding each one of these service quality parameters. Based on the hypotheses testing, it was noticed that only advertisement clients that maintain a connection to the television network from 5 to 10 years do show a significant different perception of the TV advertisement service provided by the company in what the Hard Process Quality parameter is concerned. Through the collected data content analysis, it was possible to obtain the percentage of clients which share the same opinions and suggestions for improvement. Finally, based on one of the four service quality parameter in a B2B context, managerial suggestions were developed aiming at improving the television network advertisement perceived quality service.Keywords: B2B, case study, INDSERV, perceived service quality
Procedia PDF Downloads 2012791 The Use of Hearing Protection Devices and Hearing Loss in Steel Industry Workers in Samut Prakan Province, Thailand
Authors: Petcharat Kerdonfag, Surasak Taneepanichskul, Winai Wadwongtham
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Background: Although there have not been effective treatments for Noise Induced Hearing Loss (NIHL), it can be definitely preventable with promoting the use of Hearing Protection devices (HPDs) among workers who have been exposed to excessive noise for a long period. Objectives: The objectives of this study were to explore the use of HPDs among steel industrial workers in the high noise level zone in Samut Prakan province, Thailand and to examine the relationships of the HPDs use and hearing loss. Materials and Methods: In this cross-sectional study, eligible ninety-three participants were recruited in the designated zone of higher noise (> 85dBA) of two factories, using simple random sampling. The use of HPDs was gathered by the self-record form, examined and confirmed by the researcher team. Hearing loss was assessed by the audiometric screening at the regional Samut Prakan hospital. If an average threshold level exceeds 25 dBA at high frequency (4 and 6 Hz) in each ear, participants would be lost of hearing. Data were collected from October to December, 2016. All participants were examined by the same examiners for the validity. An Audiometric testing was performed with the participants who have been exposed to high noise levels at least 14 hours from workplace. Results: Sixty participants (64.5%) had secondary level of education. The average mean score of percent time of using HPDs was 60.5% (SD = 25.34). Sixty-seven participants (72.0%) had abnormal hearing which they have still needed to increase lower percent time of using HPDs (Mean = 37.01, SD = 23.81) than those having normal hearing (Mean = 45.77, SD = 28.44). However, there was no difference in the mean average of percent time of using HPDs between these two groups.Conclusion: The findings of this study have confirmed that the steel industrial workers still need to be motivated to use HPDs regularly. Future research should pay more attentions for creating a meaningful innovation to steel industrial workers.Keywords: hearing protection devices, noise induced hearing loss, audiometric testing, steel industry
Procedia PDF Downloads 2422790 Consumers’ Responses to Non-Traditional Marketing Communication Strategies for Advertising Herbal Products
Authors: Chioma Ifeoma Agbasimelo, Stephen Afam Kenechukwu
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The study examined consumers’ responses to non-traditional marketing communication strategies in advertising herbal products. The study identified the following non-traditional marketing communication strategies: (a) trado-instrumental marketing strategy, (b) trado-demonstrative marketing strategy, and (c) trado-iconographic marketing strategy. Anchored on the Black Box Theory, it adopted the survey design of three metropolises (Awka, Onitsha, and Nnewi) in Anambra State, Nigeria. Major findings indicated that among the identified strategies, the trado-instrumental marketing strategy is the most dominant strategy. Other strategies: (b) trado-demonstrative marketing strategy and (c) trado-iconographic marketing strategy are sparingly used in semi-urban cities. It also found that consumers’ preferences and adoption of non-traditional marketing communication were minimal. Based on the findings, there is a need to create a unified system of integration of both traditional and non-traditional marketing communication strategies due to technology interfaces.Keywords: advertising, consumers’ responses, herbal products, non-traditional marketing communication strategies
Procedia PDF Downloads 862789 Determination of Natural Gamma Radioactivity in Sand along the Black Sea Coastal Region of Giresun, North Turkey
Authors: A. Karadeniz, Belgin Kucukomeroglu
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In this study natural gamma radioactivity levels are determined on sands along the coastal regions of Giresun/Turkey. The coast of Giresun about 290 km long in investigated to collect 101 sand samples. Natural and artificial radioactivity concentrations of sand samples were measured by using HPGe gamma spectrometry. The average activity concentrations of 238U, 232Th, 40K and 137Cs on sand samples of Giresun were found to be 10.83±2.92 Bq/kg, 21.28±3.22 Bq/kg, 6.42±1.06 Bq/kg, 230.94±10.67 Bq/kg respectively. The average activity concentrations for these radionuclides were compared with the reported data of other parts of Turkey and other countries. The average absorbed dose rate for Giresun was calculated to be 38.68 nGy/h respectively. This value is significantly lower than the World averaged value of 60 nGy/h. The external annual effective dose rate concentration in Giresun was found to be 0.047 mSv/y respectively. This result is much lower than the recommeded limit of 5 mSv/y. The external hazard dose rate for Giresun weas calculated to be 0.21 respectively. This result is much lower than the recommended limit of 1.0.Keywords: concentration, radioactivity, Giresun, natural gamma radioactivity
Procedia PDF Downloads 3832788 In Silico Modeling of Drugs Milk/Plasma Ratio in Human Breast Milk Using Structures Descriptors
Authors: Navid Kaboudi, Ali Shayanfar
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Introduction: Feeding infants with safe milk from the beginning of their life is an important issue. Drugs which are used by mothers can affect the composition of milk in a way that is not only unsuitable, but also toxic for infants. Consuming permeable drugs during that sensitive period by mother could lead to serious side effects to the infant. Due to the ethical restrictions of drug testing on humans, especially women, during their lactation period, computational approaches based on structural parameters could be useful. The aim of this study is to develop mechanistic models to predict the M/P ratio of drugs during breastfeeding period based on their structural descriptors. Methods: Two hundred and nine different chemicals with their M/P ratio were used in this study. All drugs were categorized into two groups based on their M/P value as Malone classification: 1: Drugs with M/P>1, which are considered as high risk 2: Drugs with M/P>1, which are considered as low risk Thirty eight chemical descriptors were calculated by ACD/labs 6.00 and Data warrior software in order to assess the penetration during breastfeeding period. Later on, four specific models based on the number of hydrogen bond acceptors, polar surface area, total surface area, and number of acidic oxygen were established for the prediction. The mentioned descriptors can predict the penetration with an acceptable accuracy. For the remaining compounds (N= 147, 158, 160, and 174 for models 1 to 4, respectively) of each model binary regression with SPSS 21 was done in order to give us a model to predict the penetration ratio of compounds. Only structural descriptors with p-value<0.1 remained in the final model. Results and discussion: Four different models based on the number of hydrogen bond acceptors, polar surface area, and total surface area were obtained in order to predict the penetration of drugs into human milk during breastfeeding period About 3-4% of milk consists of lipids, and the amount of lipid after parturition increases. Lipid soluble drugs diffuse alongside with fats from plasma to mammary glands. lipophilicity plays a vital role in predicting the penetration class of drugs during lactation period. It was shown in the logistic regression models that compounds with number of hydrogen bond acceptors, PSA and TSA above 5, 90 and 25 respectively, are less permeable to milk because they are less soluble in the amount of fats in milk. The pH of milk is acidic and due to that, basic compounds tend to be concentrated in milk than plasma while acidic compounds may consist lower concentrations in milk than plasma. Conclusion: In this study, we developed four regression-based models to predict the penetration class of drugs during the lactation period. The obtained models can lead to a higher speed in drug development process, saving energy, and costs. Milk/plasma ratio assessment of drugs requires multiple steps of animal testing, which has its own ethical issues. QSAR modeling could help scientist to reduce the amount of animal testing, and our models are also eligible to do that.Keywords: logistic regression, breastfeeding, descriptors, penetration
Procedia PDF Downloads 622787 Bacteriophages for Sustainable Wastewater Treatment: Application in Black Water Decontamination with an Emphasis to DRDO Biotoilet
Authors: Sonika Sharma, Mohan G. Vairale, Sibnarayan Datta, Soumya Chatterjee, Dharmendra Dubey, Rajesh Prasad, Raghvendra Budhauliya, Bidisha Das, Vijay Veer
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Bacteriophages are viruses that parasitize specific bacteria and multiply in metabolising host bacteria. Bacteriophages hunt for a single or a subset of bacterial species, making them potential antibacterial agents. Utilizing the ability of phages to control bacterial populations has several applications from medical to the fields of agriculture, aquaculture and the food industry. However, harnessing phage based techniques in wastewater treatments to improve quality of effluent and sludge release into the environment is a potential area for R&D application. Phage mediated bactericidal effect in any wastewater treatment process has many controlling factors that lead to treatment performance. In laboratory conditions, titer of bacteriophages (coliphages) isolated from effluent water of a specially designed anaerobic digester of human night soil (DRDO Biotoilet) was successfully increased with a modified protocol of the classical double layer agar technique. Enrichment of the same was carried out and efficacy of the phage enriched medium was evaluated at different conditions (specific media, temperature, storage conditions). Growth optimization study was carried out on different media like soybean casein digest medium (Tryptone soya medium), Luria-Bertani medium, phage deca broth medium and MNA medium (Modified nutrient medium). Further, temperature-phage yield relationship was also observed at three different temperatures 27˚C, 37˚C and 44˚C at laboratory condition. Results showed the higher activity of coliphage 27˚C and at 37˚C. Further, addition of divalent ions (10mM MgCl2, 5mM CaCl2) and 5% glycerol resulted in a significant increase in phage titer. Besides this, effect of antibiotics addition like ampicillin and kanamycin at different concentration on plaque formation was analysed and reported that ampicillin at a concentration of 1mg/ml ampicillin stimulates phage infection and results in more number of plaques. Experiments to test viability of phage showed that it can remain active for 6 months at 4˚C in fresh tryptone soya broth supplemented with fresh culture of coliforms (early log phase). The application of bacteriophages (especially coliphages) for treatment of effluent of human faecal matter contaminated effluent water is unique. This environment-friendly treatment system not only reduces the pathogenic coliforms, but also decreases the competition between nuisance bacteria and functionally important microbial populations. Therefore, the phage based cocktail to treat fecal pathogenic bacteria present in black water has many implication in wastewater treatment processes including ‘DRDO Biotoilet’, which is an ecofriendly appropriate and affordable human faecal matter treatment technology for different climates and situations.Keywords: wastewater, microbes, virus, biotoilet, phage viability
Procedia PDF Downloads 4292786 Towards Safety-Oriented System Design: Preventing Operator Errors by Scenario-Based Models
Authors: Avi Harel
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Most accidents are commonly attributed in hindsight to human errors, yet most methodologies for safety focus on technical issues. According to the Black Swan theory, this paradox is due to insufficient data about the ways systems fail. The article presents a study of the sources of errors, and proposes a methodology for utility-oriented design, comprising methods for coping with each of the sources identified. Accident analysis indicates that errors typically result from difficulties of operating in exceptional conditions. Therefore, following STAMP, the focus should be on preventing exceptions. Exception analysis indicates that typically they involve an improper account of the operational scenario, due to deficiencies in the system integration. The methodology proposes a model, which is a formal definition of the system operation, as well as principles and guidelines for safety-oriented system integration. The article calls to develop and integrate tools for recording and analysis of the system activity during the operation, required to implement validate the model.Keywords: accidents, complexity, errors, exceptions, interaction, modeling, resilience, risks
Procedia PDF Downloads 1912785 Modeling of Building a Conceptual Scheme for Multimodal Freight Transportation Information System
Authors: Gia Surguladze, Nino Topuria, Lily Petriashvili, Giorgi Surguladze
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Modeling of building processes of a multimodal freight transportation support information system is discussed based on modern CASE technologies. Functional efficiencies of ports in the eastern part of the Black Sea are analyzed taking into account their ecological, seasonal, resource usage parameters. By resources, we mean capacities of berths, cranes, automotive transport, as well as work crews and neighbouring airports. For the purpose of designing database of computer support system for Managerial (Logistics) function, using Object-Role Modeling (ORM) tool (NORMA – Natural ORM Architecture) is proposed, after which Entity Relationship Model (ERM) is generated in automated process. The software is developed based on Process-Oriented and Service-Oriented architecture, in Visual Studio.NET environment.Keywords: seaport resources, business-processes, multimodal transportation, CASE technology, object-role model, entity relationship model, SOA
Procedia PDF Downloads 4172784 Stability of Pump Station Cavern in Chagrin Shale with Time
Authors: Mohammad Moridzadeh, Mohammad Djavid, Barry Doyle
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An assessment of the long-term stability of a cavern in Chagrin shale excavated by the sequential excavation method was performed during and after construction. During the excavation of the cavern, deformations of rock mass were measured at the surface of excavation and within the rock mass by surface and deep measurement instruments. Rock deformations were measured during construction which appeared to result from the as-built excavation sequence that had potentially disturbed the rock and its behavior. Also some additional time dependent rock deformations were observed during and post excavation. Several opinions have been expressed to explain this time dependent deformation including stress changes induced by excavation, strain softening (or creep) in the beddings with and without clay and creep of the shaley rock under compressive stresses. In order to analyze and replicate rock behavior observed during excavation, including current and post excavation elastic, plastic, and time dependent deformation, Finite Element Analysis (FEA) was performed. The analysis was also intended to estimate long term deformation of the rock mass around the excavation. Rock mass behavior including time dependent deformation was measured by means of rock surface convergence points, MPBXs, extended creep testing on the long anchors, and load history data from load cells attached to several long anchors. Direct creep testing of Chagrin Shale was performed on core samples from the wall of the Pump Room. Results of these measurements were used to calibrate the FEA of the excavation. These analyses incorporate time dependent constitutive modeling for the rock to evaluate the potential long term movement in the roof, walls, and invert of the cavern. The modeling was performed due to the concerns regarding the unanticipated behavior of the rock mass as well as the forecast of long term deformation and stability of rock around the excavation.Keywords: Cavern, Chagrin shale, creep, finite element.
Procedia PDF Downloads 342