Search results for: project–based organizations

Authors: Alice Robba, Renaud Bouchet, Celine Barchasz, Jean-Francois Colin, Erik Elkaim, Kristina Kvashnina, Gavin Vaughan, Matjaz Kavcic, Fannie Alloin

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With their high theoretical energy density (~2600 Wh.kg-1), lithium/sulfur (Li/S) batteries are highly promising, but these systems are still poorly understood due to the complex mechanisms/equilibria involved. Replacing S8 by Li2S as the active material allows the use of safer negative electrodes, like silicon, instead of lithium metal. S8 and Li2S have different conductivity and solubility properties, resulting in a profoundly changed activation process during the first cycle. Particularly, during the first charge a high polarization and a lack of reproducibility between tests are observed. Differences observed between raw Li2S material (micron-sized) and that electrochemically produced in a battery (nano-sized) may indicate that the electrochemical process depends on the particle size. Then the major focus of the presented work is to deepen the understanding of the Li2S material charge mechanism, and more precisely to characterize the effect of the initial Li2S particle size both on the mechanism and the electrode preparation process. To do so, Li2S nanoparticles were synthetized according to two ways: a liquid path synthesis and a dissolution in ethanol, allowing Li2S nanoparticles/carbon composites to be made. Preliminary chemical and electrochemical tests show that starting with Li2S nanoparticles could effectively suppress the high initial polarization but also influence the electrode slurry preparation. Indeed, it has been shown that classical formulation process - a slurry composed of Polyvinylidone Fluoride polymer dissolved in N-methyle-2-pyrrolidone - cannot be used with Li2S nanoparticles. This reveals a complete different Li2S material behavior regarding polymers and organic solvents when going at the nanometric scale. Then the coupling between two operando characterizations such as X-Ray Diffraction (XRD) and X-Ray Absorption and Emission Spectroscopy (XAS/XES) have been carried out in order to interpret the poorly understood first charge. This study discloses that initial particle size of the active material has a great impact on the working mechanism and particularly on the different equilibria involved during the first charge of the Li2S based Li-ion batteries. These results explain the electrochemical differences and particularly the polarization differences observed during the first charge between micrometric and nanometric Li2S-based electrodes. Finally, this work could lead to a better active material design and so to more efficient Li2S-based batteries.

Keywords: Li-ion/Sulfur batteries, Li2S nanoparticles effect, Operando characterizations, working mechanism

Procedia PDF Downloads 263

Authors: Youlu Huang, Huanjun Jiang

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A large number of old masonry buildings built in the last century still remain in the city. It generates the problems of unsafety, obsolescence, and non-habitability. In recent years, many old buildings have been reconstructed through renovating façade, strengthening, and adding floors. However, most projects only provide a solution for a single problem. It is difficult to comprehensively solve problems of poor safety and lack of building functions. Therefore, a comprehensive functional renovation program of adding reinforced concrete frame story at the bottom via integrally lifting the building and then strengthening the building was put forward. Based on field measurement and YJK calculation software, the seismic performance of an actual three-story masonry structure in Shanghai was identified. The results show that the material strength of masonry is low, and the bearing capacity of some masonry walls could not meet the code requirements. The elastoplastic time history analysis of the structure was carried out by using SAP2000 software. The results show that under the 7 degrees rare earthquake, the seismic performance of the structure reaches 'serious damage' performance level. Based on the code requirements of the stiffness ration of the bottom frame (lateral stiffness ration of the transition masonry story and frame story), the bottom frame story was designed. The integral lifting process of the masonry building was introduced based on many engineering examples. The reinforced methods for the bottom frame structure strengthened by the steel-reinforced mesh mortar surface layer (SRMM) and base isolators, respectively, were proposed. The time history analysis of the two kinds of structures, under the frequent earthquake, the fortification earthquake, and the rare earthquake, was conducted by SAP2000 software. For the bottom frame structure, the results show that the seismic response of the masonry floor is significantly reduced after reinforced by the two methods compared to the masonry structure. The previous earthquake disaster indicated that the bottom frame is vulnerable to serious damage under a strong earthquake. The analysis results showed that under the rare earthquake, the inter-story displacement angle of the bottom frame floor meets the 1/100 limit value of the seismic code. The inter-story drift of the masonry floor for the base isolated structure under different levels of earthquakes is similar to that of structure with SRMM, while the base-isolated program is better to protect the bottom frame. Both reinforced methods could significantly improve the seismic performance of the bottom frame structure.

Keywords: old buildings, adding story, seismic strengthening, seismic performance

Procedia PDF Downloads 118

Authors: Victoria Brennan, Andrea Mallaburn, Linda Seton

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Science outreach programmes connect school pupils with external agencies to provide activities and experiences that enhance their exposure to science. It can be argued that these programmes not only aim to support teachers with curriculum engagement and promote scientific literacy but also provide pivotal opportunities to spark scientific interest in students. In turn, a further objective of these programmes is to increase awareness of career opportunities within this field. Although outreach work is also often described as a fun and satisfying venture, a plethora of researchers express caution to how successful the processes are to increases engagement post-16 in science. When researching the impact of outreach programmes, it is often student feedback regarding the activities or enrolment numbers to particular science courses post-16, which are generated and analysed. Although this is informative, the longevity of the programme’s impact could be better informed by the teacher’s perceptions; the evidence of which is far more limited in the literature. In addition, there are strong suggestions that teachers can have an indirect impact on a student’s own self-concept. These themes shape the focus and importance of this ongoing research project as it presents the rationale that teachers are under-used resources when it comes to considering the design of science outreach programmes. Therefore, the end result of the research will consist of a presentation of an ‘optimum’ model of outreach. The result of which should be of interest to the wider stakeholders such as universities or private or government organisations who design science outreach programmes in the hope to recruit future scientists. During phase one, questionnaires (n=52) and interviews (n=8) have generated both quantitative and qualitative data. These have been analysed using the Wilcoxon non-parametric test to compare teachers’ perceptions of science outreach interventions and thematic analysis for open-ended questions. Both of these research activities provide an opportunity for a cross-section of teacher opinions of science outreach to be obtained across all educational levels. Therefore, an early draft of the ‘optimum’ model of science outreach delivery was generated using both the wealth of literature and primary data. This final (ongoing) phase aims to refine this model using teacher focus groups to provide constructive feedback about the proposed model. The analysis uses principles of modified Grounded Theory to ensure that focus group data is used to further strengthen the model. Therefore, this research uses a pragmatist approach as it aims to focus on the strengths of the different paradigms encountered to ensure the data collected will provide the most suitable information to create an improved model of sustainable outreach. The results discussed will focus on this ‘optimum’ model and teachers’ perceptions of benefits and drawbacks when it comes to engaging with science outreach work. Although the model is still a ‘work in progress’, it provides both insight into how teachers feel outreach delivery can be a sustainable intervention tool within the classroom and what providers of such programmes should consider when designing science outreach activities.

Keywords: educational partnerships, science education, science outreach, teachers

Procedia PDF Downloads 120

Authors: Liliana Villavicencio, Yohn Garcia, Pallavi Singh, Luis Fernando Cruz, Wilfrido Moreno

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Psychophysiological adaptive automation is a concept that combines human physiological data and computer algorithms to create personalized interfaces and experiences for users. This approach aims to enhance human learning by adapting to individual needs and preferences and optimizing the interaction between humans and machines. According to neurosciences, the working memory demand during the student learning process is modified when the student is learning a new subject or topic, managing and/or fulfilling a specific task goal. A sudden increase in working memory demand modifies the level of students’ attention, engagement, and cognitive load. The proposed psychophysiological adaptive automation system will adapt the task requirements to optimize cognitive load, the process output variable, by monitoring the student's brain activity. Cognitive load changes according to the student’s previous knowledge, the type of task, the difficulty level of the task, and the overall psychophysiological state of the student. Scaling the measured cognitive load as low, medium, or high; the system will assign a task difficulty level to the next task according to the ratio between the previous-task difficulty level and student stress. For instance, if a student becomes stressed or overwhelmed during a particular task, the system detects this through signal measurements such as brain waves, heart rate variability, or any other psychophysiological variables analyzed to adjust the task difficulty level. The control of engagement and stress are considered internal variables for the hypermedia system which selects between three different types of instructional material. This work assesses the feasibility of a fuzzy controller to track a student's physiological responses and adjust the learning content and pace accordingly. Using an industrial automation approach, the proposed fuzzy logic controller is based on linguistic rules that complement the instrumentation of the system to monitor and control the delivery of instructional material to the students. From the test results, it can be proved that the implemented fuzzy controller can satisfactorily regulate the delivery of academic content based on the working memory demand without compromising students’ health. This work has a potential application in the instructional design of virtual reality environments for training and education.

Keywords: fuzzy logic controller, hypermedia control system, personalized education, psychophysiological adaptive automation

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Authors: Seyed Mohammad Hashemi, Shahrokh Barati

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The problem of fault-tolerant control (FTC) by accommodation method has been studied in this paper. The fault occurs in any system components such as actuators, sensors or internal structure of the system and leads to loss of performance and instability of the system. When a fault occurs, the purpose of the fault-tolerant control is designate strategy that can keep the control loop stable and system performance as much as possible perform it without shutting down the system. Here, the section of fault detection and isolation (FDI) system has been evaluated with regard to actuator's fault. Designing a fault detection and isolation system for a multi input-multi output (MIMO) is done by an unknown input observer, so the system is divided to several subsystems as the effect of other inputs such as disturbing given system state equations. In this observer design method, the effect of these disturbances will weaken and the only fault is detected on specific input. The results of this approach simulation can confirm the ability of the fault detection and isolation system design. After fault detection and isolation, it is necessary to redesign controller based on a suitable modification. In this regard after the use of unknown input observer theory and obtain residual signal and evaluate it, PID controller parameters redesigned for iterative. Stability of the closed loop system has proved in the presence of this method. Also, In order to soften the volatility caused by Annie variations of the PID controller parameters, modifying Sigma as a way acceptable solution used. Finally, the simulation results of three tank popular example confirm the accuracy of performance.

Keywords: fault tolerant control, fault detection and isolation, actuator fault, unknown input observer

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Authors: Sanjin Kršćanski, Josip Brnić

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Virtual Crack Closure Technique (VCCT) is a method used for calculating stress intensity factor (SIF) of a cracked body that is easily implemented on top of basic finite element (FE) codes and as such can be applied on the various component geometries. It is a relatively simple method that does not require any special finite elements to be used and is usually used for calculating stress intensity factors at the crack tip for components made of brittle materials. This paper studies applicability and accuracy of VCCT applied on standard metal specimens containing trough thickness crack, subjected to an in-plane bending load. Finite element analyses were performed using regular 4-node, regular 8-node and a modified quarter-point 8-node 2D elements. Stress intensity factor was calculated from the FE model results for a given crack length, using data available from FE analysis and a custom programmed algorithm based on virtual crack closure technique. Influence of the finite element size on the accuracy of calculated SIF was also studied. The final part of this paper includes a comparison of calculated stress intensity factors with results obtained from analytical expressions found in available literature and in ASTM standard. Results calculated by this algorithm based on VCCT were found to be in good correlation with results obtained with mentioned analytical expressions.

Keywords: VCCT, stress intensity factor, finite element analysis, 2D finite elements, bending

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Authors: Douglas J. Kube

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At the beginning of the COVID-19 pandemic, the Canadian Red Cross deployed workers into long-term care homes across Canada to support our most vulnerable citizens. It began by recruiting and training small teams of workers to provide non-clinical services for facilities in outbreak. Deployed workers were trained on an approach based on successful Red Cross deployments used with Ebola in which zones were established, levels of protection used, and strict protocols followed to prevent exposure. This paper addresses aspects of human performance through a safety culture lens. The Red Cross deployments highlight valuable insights and are an excellent case study in the principles of human performance and organizational culture. This paper looks at human performance principles, including human fallibility, predictability of error-likely situations, avoiding events by understanding reasons mistakes occur, and the influence on behaviour by organizational factors. This study demonstrates how the Red Cross’s organizational culture and work design positively influenced performance to protect workers and residents/clients. Lastly, this paper shares lessons that can be applied in many workplaces to improve worker health and safety and safety culture. This critical examination is based on the author’s experience as a Senior Occupational Health and Safety Advisor with the Red Cross during the pandemic as part of the team responsible for developing and implementing biological safety practices in long-term care deployments.

Keywords: COVID, human performance, organizational culture, work design

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Authors: Shashank Gahlaut, Chandrashekhar Sharan, J. P. Singh

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Increasing incidence of antibiotic-resistant bacteria is a big concern for the treatment of pathogenic diseases. The effect of treatment of patients with antibiotics often leads to the evolution of antibiotic resistance in the pathogens. The detection of antibiotic or antimicrobial resistant bacteria (microbes) is quite essential as it is becoming one of the big threats globally. Here we propose a novel technique to tackle this problem. We are taking a step forward to prevent the infections and diseases due to drug resistant microbes. This detection is based on some unique features of silver (a noble metal) nanorods (AgNRs) which are fabricated by a physical deposition method called thermal glancing angle deposition (GLAD). Silver nanorods are found to be highly sensitive and selective for hydrogen sulfide (H2S) gas. Color and water wetting (contact angle) of AgNRs are two parameters what are effected in the presence of this gas. H₂S is one of the major gaseous products evolved in the bacterial metabolic process. It is also known as gasotransmitter that transmits some biological singles in living systems. Nitric Oxide (NO) and Carbon mono oxide (CO) are two another members of this family. Orlowski (1895) observed the emission of H₂S by the bacteria for the first time. Most of the microorganism produce these gases. Here we are focusing on H₂S gas evolution to determine live/dead and antibiotic-resistant bacteria. AgNRs array has been used for the detection of H₂S from micro-organisms. A mobile app is also developed to make it easy, portable, user-friendly, and cost-effective.

Keywords: antibiotic resistance, hydrogen sulfide, live and dead bacteria, mobile app

Procedia PDF Downloads 142

Authors: Rohollah Asadian Kohestani, Nazanin Sedghi

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As the number of banks and financial institutions working in Iran has been significantly increased, the attracting and retaining customers and encouraging them to continually use the modern banking services have been important and vital issues. Therefore, there would be a serious competition without a deep perception of consumers and fitness of banking services with their needs in the current economic conditions of Iran. It should be noted that concepts such as 'brand equity' is defined based on the view of consumers; however, it is also focused by shareholders, competitors and other beneficiaries of a firm in addition to bank and its consumers. This study examines the impact of brand equity on the competitive advantage in the banking industry as intensive competition between brands of different banks leads to pay more attention to the brands. This research is based on the Aaker’s model examining the impact of four dimensions of brand equity on the competitive advantage of private banks in Behshahr city. Moreover, conducting an applied research and data analysis has been carried out by a descriptive method. Data collection was done using literature review and questionnaire. A 'simple random' methodology was selected for sampling staff of banks while sampling methodology to select consumers of banks was the distribution of questionnaire between staff and consumers of five private banks including Tejarat, Mellat, Refah K., Ghavamin and, Tose’e Ta’avon banks. Results show that there is a significant relationship between brand equity and their competitive advantage. In this research, software of SPSS 16 and LISREL 8.5, as well as different methods of descriptive inferential statistics for analyzing data and test hypotheses, were employed.

Keywords: brand awareness, brand loyalty, brand equity, competitive advantage

Procedia PDF Downloads 135

Authors: C. Amer, M. Sahin

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The design of an optimised horizontal axis 5-meter-long wind turbine rotor blade in according with IEC 61400-2 standard is a research and development project in order to fulfil the requirements of high efficiency of torque from wind production and to optimise the structural components to the lightest and strongest way possible. For this purpose, a research study is presented here by focusing on the structural characteristics of a composite wind turbine blade via finite element modelling and analysis tools. In this work, first, the required data regarding the general geometrical parts are gathered. Then, the airfoil geometries are created at various sections along the span of the blade by using CATIA software to obtain the two surfaces, namely; the suction and the pressure side of the blade in which there is a hat shaped fibre reinforced plastic spar beam, so-called chassis starting at 0.5m from the root of the blade and extends up to 4 m and filled with a foam core. The root part connecting the blade to the main rotor differential metallic hub having twelve hollow threaded studs is then modelled. The materials are assigned as two different types of glass fabrics, polymeric foam core material and the steel-balsa wood combination for the root connection parts. The glass fabrics are applied using hand wet lay-up lamination with epoxy resin as METYX L600E10C-0, is the unidirectional continuous fibres and METYX XL800E10F having a tri-axial architecture with fibres in the 0,+45,-45 degree orientations in a ratio of 2:1:1. Divinycell H45 is used as the polymeric foam. The finite element modelling of the blade is performed via MSC PATRAN software with various meshes created on each structural part considering shell type for all surface geometries, and lumped mass were added to simulate extra adhesive locations. For the static analysis, the boundary conditions are assigned as fixed at the root through aforementioned bolts, where for dynamic analysis both fixed-free and free-free boundary conditions are made. By also taking the mesh independency into account, MSC NASTRAN is used as a solver for both analyses. The static analysis aims the tip deflection of the blade under its own weight and the dynamic analysis comprises normal mode dynamic analysis performed in order to obtain the natural frequencies and corresponding mode shapes focusing the first five in and out-of-plane bending and the torsional modes of the blade. The analyses results of this study are then used as a benchmark prior to modal testing, where the experiments over the produced wind turbine rotor blade has approved the analytical calculations.

Keywords: dynamic analysis, fiber reinforced composites, horizontal axis wind turbine blade, hand-wet layup, modal testing

Procedia PDF Downloads 420

Authors: Andreas Lind, Aitor Iriondo Pascual, Dan Hogberg, Lars Hanson

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Factory setup lifecycles are most often described and prepared in CAD environments; the preparation is based on experience and inputs from several cross-disciplinary processes. Early in the factory setup preparation, a so-called block layout is created. The intention is to describe a high-level view of the intended factory setup and to claim area reservations and allocations. Factory areas are then blocked, i.e., targeted to be used for specific intended resources and processes, later redefined with detailed factory setup layouts. Each detailed layout is based on the block layout and inputs from cross-disciplinary preparation processes, such as manufacturing sequence, productivity, workers’ workplace requirements, and resource setup preparation. However, this activity is often not carried out with all variables considered simultaneously, which might entail a risk of sub-optimizing the detailed layout based on manual decisions. Therefore, this work aims to realize a digital method for assembly manufacturing layout planning where productivity, area utilization, and ergonomics can be considered simultaneously in a cross-disciplinary manner. The purpose of the digital method is to support engineers in finding optimized designs of detailed layouts for assembly manufacturing factories, thereby facilitating better decisions regarding setups of future factories. Input datasets are company-specific descriptions of required dimensions for specific area reservations, such as defined dimensions of a worker’s workplace, material façades, aisles, and the sequence to realize the product assembly manufacturing process. To test and iteratively develop the digital method, a demonstrator has been developed with an adaptation of existing software that simulates and proposes optimized designs of detailed layouts. Since the method is to consider productivity, ergonomics, area utilization, and constraints from the automatically generated block layout, a multi-objective optimization approach is utilized. In the demonstrator, the input data are sent to the simulation software industrial path solutions (IPS). Based on the input and Lua scripts, the IPS software generates a block layout in compliance with the company’s defined dimensions of area reservations. Communication is then established between the IPS and the software EPP (Ergonomics in Productivity Platform), including intended resource descriptions, assembly manufacturing process, and manikin (digital human) resources. Using multi-objective optimization approaches, the EPP software then calculates layout proposals that are sent iteratively and simulated and rendered in IPS, following the rules and regulations defined in the block layout as well as productivity and ergonomics constraints and objectives. The software demonstrator is promising. The software can handle several parameters to optimize the detailed layout simultaneously and can put forward several proposals. It can optimize multiple parameters or weight the parameters to fine-tune the optimal result of the detailed layout. The intention of the demonstrator is to make the preparation between cross-disciplinary silos transparent and achieve a common preparation of the assembly manufacturing factory setup, thereby facilitating better decisions.

Keywords: factory setup, multi-objective, optimization, simulation

Procedia PDF Downloads 143

Authors: Elbadawy A. Kamoun

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Magnetically responsive hydrogel nanocomposite (NCH) based on composites of superparamagnetic of Fe3O4 nano-particles and temperature responsive hydrogel matrices were developed. The nanocomposite hydrogel system based on the temperature sensitive N-isopropylacrylamide hydrogels crosslinked by poly(ethylene glycol)-400 dimethacrylate (PEG400DMA) incorporating with chitosan derivative, was synthesized and characterized. Likewise, the NCH system was synthesized by visible-light free radical photopolymerization, using carboxylated camphorquinone-amine system to avoid the common risks of the use of UV-light especially in hyperthermia treatment. Superparamagnetic of iron oxide nanoparticles were introduced into the hydrogel system by polymerizing mixture technique and monomer solution. FT-IR with Raman spectroscopy and Wide angle-XRD analysis were utilized to verify the chemical structure of NCH and exfoliation reaction for nanoparticles, respectively. Additionally, morphological structure of NCH was investigated using SEM and TEM photographs. The swelling responsive of the current nanocomposite hydrogel system with different crosslinking conditions, temperature, magnetic field efficiency, and the presence effect of magnetic nanoparticles were evaluated. Notably, hydrolytic degradation of this system was proved in vitro application. While, in-vivo release profile behavior is under investigation nowadays. Moreover, the compatibility and cytotoxicity tests were previously investigated in our studies for photoinitiating system. These systems show promised polymeric material candidate devices and are expected to have a wide applicability in various biomedical applications as mildly.

Keywords: hydrogel nanocomposites, tempretaure-responsive hydrogel, superparamagnetic nanoparticles, hyperthermia therapy

Procedia PDF Downloads 275

Authors: Nunuy Nuraeni, Vera Amalia Lestari, Atri Laranova, Viena Nissa Mien Fadhillah, Mutia, Muhammad Ikhlas Abdian Putra

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Introduction: Obesity is a common disease with high prevalence especially in developing countries including Indonesia. The obesitygenic lifestyle such as excessive intake of food, sedentary lifestyle is the major environmental etiologies of obesity. Obesity is also as one of burden disease with high morbidity due to its complication, such as diabetes mellitus and hypertension. The objective of this literature review is to know how the Epigallocathecin-3-Gallate of Green tea or Camellia sinensis effect as anti-obesity agent and reduce the complication of obesity. Material and Methods: This study based on the secondary data analysis complemented by primary data collection from several journal and textbook. We identified the effect of Epigallocathecin-3-Gallate of Green tea or Camellia sinensis as adjuvant therapy for management obesity and to prevent the complications of obesity. Results: Based on the result, Green tea or Camellia sinensis contain Epigallocathecin-3-Gallate (EGCG) that has anti-obesity effect such as induce apoptosis, inhibit adipogenesis, increasing lipolytic activity, increasing fat oxidation and thermogenesis. Discussion: EGCG are naturally distributed in green tea, that contains a biological activity that has a potential effect to treat obesity. Conclusion: EGCG are capable to treat obesity. By consuming EGCG can prevent obesity in normal health person and prevent complication in patient with obesity.

Keywords: adjuvant therapy, anti-obesity effect, complication, epigallocathecin-3-gallate, obesity

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Authors: Tarek Abdoun, Ricardo Dobry

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This paper is a systematic effort to clarify why field liquefaction charts based on Seed and Idriss’ Simplified Procedure work so well. This is a necessary step toward integrating the states of the art (SOA) and practice (SOP) for evaluating liquefaction and its effects. The SOA relies mostly on laboratory measurements and correlations with void ratio and relative density of the sand. The SOP is based on field measurements of penetration resistance and shear wave velocity coupled with empirical or semi-empirical correlations. This gap slows down further progress in both SOP and SOA. The paper accomplishes its objective through: a literature review of relevant aspects of the SOA including factors influencing threshold shear strain and pore pressure buildup during cyclic strain-controlled tests; a discussion of factors influencing field penetration resistance and shear wave velocity; and a discussion of the meaning of the curves in the liquefaction charts separating liquefaction from no liquefaction, helped by recent full-scale and centrifuge results. It is concluded that the charts are curves of constant cyclic strain at the lower end (Vs1 < 160 m/s), with this strain being about 0.03 to 0.05% for earthquake magnitude, Mw ≈ 7. It is also concluded, in a more speculative way, that the curves at the upper end probably correspond to a variable increasing cyclic strain and Ko, with this upper end controlled by over consolidated and preshaken sands, and with cyclic strains needed to cause liquefaction being as high as 0.1 to 0.3%. These conclusions are validated by application to case histories corresponding to Mw ≈ 7, mostly in the San Francisco Bay Area of California during the 1989 Loma Prieta earthquake.

Keywords: permeability, lateral spreading, liquefaction, centrifuge modeling, shear wave velocity charts

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Authors: Maria Do Carmo Baracho De Alencar

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Back pain is considered a worldwide public health problem and has led to numerous work-related absence from work and public spending on rehabilitation, as well as difficulties in the process of professional rehabilitation and return to work. Also, the rehabilitation of workers is one of the great challenges today and for the field of Workers' Health in Brazil. Aim: To investigate the procedures related to the professional rehabilitation of insured workers affected by chronic low back pain, based on the perceptions of professional counselors. Methods: A list of related professional counselors was obtained from the Professional Rehabilitation Coordination of the Baixada Santista (SP) region, and from the Social Security National Institute of Brazil, and in which cities they worked. Semistructured and individual interview was scheduled, based on a pre-elaborated script, containing questions about procedures, experiences at work and feelings. The interviews were recorded and transcribed in full for content analysis. Results: Ten (10) professional counselors of both genders and from nine (9) cities from the Baixada Santista region participated in the study. Aged between 31 and 64 years, and time in service between 4 and 38 years. Only one of the professionals was graduaded in Psychology. Among the testimonies emerged the high demand of work, the lack of interest of companies, medical authority, the social helplessness after rehabilitation process, difficulty in assessing invisible pain, and suffering, anguish, and frustration at work, between others. Conclusion: The study contributes to reflections about the importance of interdisciplinary actions and the Psychology in the processes of professional rehabilitation and readaptation in the process of return to work.

Keywords: low back pain, rehabilitation, work, occupational health

Procedia PDF Downloads 132

Authors: Cheryl Forchuk, Sandra Fisman, Steve Cordes, Dan Catunto, Katherine Krakowski, Melissa Jeffrey, John D’Oria

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The discharge of youth aged 16-25 from hospital into homelessness is a prevalent issue despite research indicating social, safety, health and economic detriments on both the individual and community. Lack of stable housing for youth discharged into homelessness results in long-term consequences, including exacerbation of health problems and costly health care service use and hospital readmission. People experiencing homelessness are four times more likely to be readmitted within one month of discharge and hospitals must spend $2,559 more per client. Finding safe housing for these individuals is imperative to their recovery and transition back to the community. People discharged from hospital to homelessness experience challenges, including poor health outcomes and increased hospital readmissions. Youth are the fastest-growing subgroup of people experiencing homelessness in Canada. The needs of youth are unique and include supports related to education, employment opportunities, and age-related service barriers. This study aims to identify the needs of youth at risk of homelessness by evaluating the efficacy of the “Preventing Discharge to No Fixed Address – Youth” (NFA-Y) program, which aims to prevent youth from being discharged from hospital into homelessness. The program connects youth aged 16-25 who are inpatients at London Health Sciences Centre and St. Joseph’s Health Care London to housing and financial support. Supports are offered through collaboration with community partners: Youth Opportunities Unlimited, Canadian Mental Health Association Elgin Middlesex, City of London Coordinated Access, Ontario Works, and Salvation Army’s Housing Stability Bank. This study was reviewed and approved by Western University’s Research Ethics Board. A series of interviews are being conducted with approximately ninety-three youth participants at three time points: baseline (pre-discharge), six, and twelve months post-discharge. Focus groups with participants, health care providers, and community partners are being conducted at three-time points. In addition, administrative data from service providers will be collected and analyzed. Since homelessness has a detrimental effect on recovery, client and community safety, and healthcare expenditure, locating safe housing for psychiatric patients has had a positive impact on treatment, rehabilitation, and the system as a whole. If successful, the findings of this project will offer safe policy alternatives for the prevention of homelessness for at-risk youth, help set them up for success in their future years, and mitigate the rise of the homeless youth population in Canada.

Keywords: youth homelessness, no-fixed address, mental health, homelessness prevention, hospital discharge

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Authors: Priyanka Chaudhary, M. Rizwan

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This paper presents a grid synchronization technique based on adaptive notch filter for SPV (Solar Photovoltaic) system along with MPPT (Maximum Power Point Tracking) techniques. An efficient grid synchronization technique offers proficient detection of various components of grid signal like phase and frequency. It also acts as a barrier for harmonics and other disturbances in grid signal. A reference phase signal synchronized with the grid voltage is provided by the grid synchronization technique to standardize the system with grid codes and power quality standards. Hence, grid synchronization unit plays important role for grid connected SPV systems. As the output of the PV array is fluctuating in nature with the meteorological parameters like irradiance, temperature, wind etc. In order to maintain a constant DC voltage at VSC (Voltage Source Converter) input, MPPT control is required to track the maximum power point from PV array. In this work, a variable step size P & O (Perturb and Observe) MPPT technique with DC/DC boost converter has been used at first stage of the system. This algorithm divides the dPpv/dVpv curve of PV panel into three separate zones i.e. zone 0, zone 1 and zone 2. A fine value of tracking step size is used in zone 0 while zone 1 and zone 2 requires a large value of step size in order to obtain a high tracking speed. Further, adaptive notch filter based control technique is proposed for VSC in PV generation system. Adaptive notch filter (ANF) approach is used to synchronize the interfaced PV system with grid to maintain the amplitude, phase and frequency parameters as well as power quality improvement. This technique offers the compensation of harmonics current and reactive power with both linear and nonlinear loads. To maintain constant DC link voltage a PI controller is also implemented and presented in this paper. The complete system has been designed, developed and simulated using SimPower System and Simulink toolbox of MATLAB. The performance analysis of three phase grid connected solar photovoltaic system has been carried out on the basis of various parameters like PV output power, PV voltage, PV current, DC link voltage, PCC (Point of Common Coupling) voltage, grid voltage, grid current, voltage source converter current, power supplied by the voltage source converter etc. The results obtained from the proposed system are found satisfactory.

Keywords: solar photovoltaic systems, MPPT, voltage source converter, grid synchronization technique

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Authors: M. F. Miah, K. M. A. Zinnah, M. J. Raihan, H. Ali, M. N. Naser

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As genetic diversity is most important for existing, breeding and production of any fish; this study was undertaken for investigating genetic diversity of freshwater mud eel, Monopterus cuchia at population level where three ecological populations such as flooded area of Sylhet (P1), open water of Moulvibazar (P2) and open water of Sunamganj (P3) districts of Bangladesh were considered. Four arbitrary RAPD primers (OPB-12, C0-4, B-03 and OPB-08) were screened and RAPD banding patterns were analyzed among the populations considering 15 individuals of each population. In total 174, 138 and 149 bands were detected in the populations of P1, P2 and P3 respectively; however, each primer revealed less number of bands in each population. 100% polymorphic loci were recorded in P2 and P3 whereas only one monomorphic locus was observed in P1, recorded 97.5% polymorphism. Different genetic parameters such as inter-individual pairwise similarity, genetic distance, Nei genetic similarity, linkage distances, cluster analysis and allelic information, etc. were considered for measuring genetic diversity. The average inter-individual pairwise similarity was recorded 2.98, 1.47 and 1.35 in P1, P2 and P3 respectively. Considering genetic distance analysis, the highest distance 1 was recorded in P2 and P3 and the lowest genetic distance 0.444 was found in P2. The average Nei genetic similarity was observed 0.19, 0.16 and 0.13 in P1, P2 and P3, respectively; however, the average linkage distance was recorded 24.92, 17.14 and 15.28 in P1, P3 and P2 respectively. Based on linkage distance, genetic clusters were generated in three populations where 6 clades and 7 clusters were found in P1, 3 clades and 5 clusters were observed in P2 and 4 clades and 7 clusters were detected in P3. In addition, allelic information was observed where the frequency of p and q alleles were observed 0.093 and 0.907 in P1, 0.076 and 0.924 in P2, 0.074 and 0.926 in P3 respectively. The average gene diversity was observed highest in P2 (0.132) followed by P3 (0.131) and P1 (0.121) respectively.

Keywords: genetic diversity, Monopterus cuchia, population, RAPD, Bangladesh

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Authors: Cao Yuping, Li Longfei, Zhao Xingfu, Zhang Yalin

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Purpose: This study examined the effects of exposure to domestic physical violence (DPV) on children’s behavior in a community sample. Method: Ninety-three 12-16 year-old adolescents exposed to DPV were matched with 54 adolescents with no exposure to DPV based on age, gender, family composition and parental age and education level. Participation included assessment with the Childhood Trauma Questionnaire (CTQ-SF) and Child Behavior Checklist (CBCL) by the adolescents and their parents respectively. Results: CBCL total score and anxiety/depression, social interaction problems, attention problems, delinquency, aggression and externalizing scores were significantly higher in adolescents exposed to DPV than those in controls (all ps<0.05).The CBCL total score and scores of anxiety/depression, social interaction problems, attention problems, delinquency, aggression and externalizing behaviors of boys were significantly higher in the research group than in the controls (all ps<0.05). Delinquency scores in abused adolescents were significantly higher than in DPV witnessed (p<0.05), but no other scores of CBCL were significant different. Different subtypes of behavioral problems were associated with different types of abuse. Conclusions: DPV exposure is associated with adverse behaviors in children, especially among boys. Children witness DPV alone have similar behavioral scores as the abused children. We recommend that both abused and DPV witness adolescents in Chinese communities need treatment to mitigate the effects on maladjusted behaviors.

Keywords: domestic violence, child, behavior, community, China

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Authors: Mohamed El Morsy, Gabriela Achtenová

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Condition monitoring is used to increase machinery availability and machinery performance, whilst reducing consequential damage, increasing machine life, reducing spare parts inventories, and reducing breakdown maintenance. An efficient condition monitoring system provides early warning of faults by predicting them at an early stage. When a localized fault occurs in gears, the vibration signals always exhibit non-stationary behavior. The periodic impulsive feature of the vibration signal appears in the time domain and the corresponding gear mesh frequency (GMF) emerges in the frequency domain. However, one limitation of frequency-domain analysis is its inability to handle non-stationary waveform signals, which are very common when machinery faults occur. Particularly at the early stage of gear failure, the GMF contains very little energy and is often overwhelmed by noise and higher-level macro-structural vibrations. An effective signal processing method would be necessary to remove such corrupting noise and interference. In this paper, a new hybrid method based on optimal Morlet wavelet filter and autocorrelation enhancement is presented. First, to eliminate the frequency associated with interferential vibrations, the vibration signal is filtered with a band-pass filter determined by a Morlet wavelet whose parameters are selected or optimized based on maximum Kurtosis. Then, to further reduce the residual in-band noise and highlight the periodic impulsive feature, an autocorrelation enhancement algorithm is applied to the filtered signal. The test stand is equipped with three dynamometers; the input dynamometer serves as the internal combustion engine, the output dynamometers induce a load on the output joint shaft flanges. The pitting defect is manufactured on the tooth side of a gear of the fifth speed on the secondary shaft. The gearbox used for experimental measurements is of the type most commonly used in modern small to mid-sized passenger cars with transversely mounted powertrain and front wheel drive: a five-speed gearbox with final drive gear and front wheel differential. The results obtained from practical experiments prove that the proposed method is very effective for gear fault diagnosis.

Keywords: wavelet analysis, pitted gear, autocorrelation, gear fault diagnosis

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Authors: Eva Filová, Jana Daňková, Věra Sovková, Matej Daniel

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Titanium alloys are biocompatible metals that are widely used in clinical practice as load bearing implants. The chemical modification may influence cell adhesion, proliferation, and differentiation as well as stiffness of the material. The aim of the study was to evaluate the adhesion, growth and differentiation of pig mesenchymal stem cells on the novel beta titanium alloy Ti36Nb6Ta compared to standard medical titanium alloy Ti6Al4V. Discs of Ti36Nb6Ta and Ti6Al4V alloy were sterilized by ethanol, put in 48-well plates, and seeded by pig mesenchymal stem cells at the density of 60×103/cm2 and cultured in Minimum essential medium (Sigma) supplemented with 10% fetal bovine serum and penicillin/streptomycin. Cell viability was evaluated using MTS assay (CellTiter 96® AQueous One Solution Cell Proliferation Assay;Promega), cell proliferation using Quant-iT™ ds DNA Assay Kit (Life Technologies). Cells were stained immunohistochemically using monoclonal antibody beta-actin, and secondary antibody conjugated with AlexaFluor®488 and subsequently the spread area of cells was measured. Cell differentiation was evaluated by alkaline phosphatase assay using p-nitrophenyl phosphate (pNPP) as a substrate; the reaction was stopped by NaOH, and the absorbance was measured at 405 nm. Osteocalcin, specific bone marker was stained immunohistochemically and subsequently visualized using confocal microscopy; the fluorescence intensity was analyzed and quantified. Moreover, gene expression of osteogenic markers osteocalcin and type I collagen was evaluated by real-time reverse transcription-PCR (qRT-PCR). For statistical evaluation, One-way ANOVA followed by Student-Newman-Keuls Method was used. For qRT-PCR, the nonparametric Kruskal-Wallis Test and Dunn's Multiple Comparison Test were used. The absorbance in MTS assay was significantly higher on titanium alloy Ti6Al4V compared to beta titanium alloy Ti36Nb6Ta on days 7 and 14. Mesenchymal stem cells were well spread on both alloys, but no difference in spread area was found. No differences in alkaline phosphatase assay, fluorescence intensity of osteocalcin as well as the expression of type I collagen, and osteocalcin genes were observed. Higher expression of type I collagen compared to osteocalcin was observed for cells on both alloys. Both beta titanium alloy Ti36Nb6Ta and titanium alloy Ti6Al4V Ti36Nb6Ta supported mesenchymal stem cellsˈ adhesion, proliferation and osteogenic differentiation. Novel beta titanium alloys Ti36Nb6Ta is a promising material for bone implantation. The project was supported by the Czech Science Foundation: grant No. 16-14758S, the Grant Agency of the Charles University, grant No. 1246314 and by the Ministry of Education, Youth and Sports NPU I: LO1309.

Keywords: beta titanium, cell growth, mesenchymal stem cells, titanium alloy, implant

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Authors: Ahmed Z. Mazen, Nejat Rahmanian, Iqbal Mujtaba, Ali Hassanpour

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In oil and gas well drilling, the drill bit is an important part of the Bottom Hole Assembly (BHA), which is installed and designed to drill and produce a hole by several mechanisms. The efficiency of the bit depends on many drilling parameters such as weight on bit, rotary speed, and mud properties. When the bit is pulled out of the hole, the evaluation of the bit damage must be recorded very carefully to guide engineers in order to select the bits for further planned wells. Having a worn bit for hole drilling may cause severe damage to bit leading to cutter or cone losses in the bottom of hole, where a fishing job will have to take place, and all of these will increase the operating cost. The main factor to reduce the cost of drilling operation is to maximize the rate of penetration by analyzing real-time data to predict the drill bit wear while drilling. There are numerous models in the literature for prediction of the rate of penetration based on drilling parameters, mostly based on empirical approaches. One of the most commonly used approaches is Bourgoyne and Young model, where the rate of penetration can be estimated by the drilling parameters as well as a wear index using an empirical correlation, provided all the constants and coefficients are accurately determined. This paper introduces a new methodology to estimate the eight coefficients for Bourgoyne and Young model using the gPROMS parameters estimation GPE (Version 4.2.0). Real data collected form similar formations (12 ¼’ sections) in two different fields in Libya are used to estimate the coefficients. The estimated coefficients are then used in the equations and applied to nearby wells in the same field to predict the bit wear.

Keywords: Bourgoyne and Young model, bit wear, gPROMS, rate of penetration

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Authors: C. Park, H. Lee, Y-J. Lee

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Aim: This study presents Interdisciplinary Collaborative Innovation Mechanism as a medium to enable the effective generation of innovations for sustainability challenges facing humanities. Background: Interdisciplinary approach of fusing disparate knowledge and perspectives from diverse expertise and subject areas is one of the key requirements to address the intricate nature of sustainability issues. There is a lack of rigorous empirical study of the systematic structure of interdisciplinary collaborative innovation for sustainability to date. Method: To address this research gap, the action research approach is adopted to develop the Interdisciplinary Collaborative Innovation Mechanism (ICIM) framework based on an empirical study of a total of 28 open innovation competitions in the format of MAKEathons between 2016 to 2023. First, the conceptual framework was formulated based on the literature findings, and the framework was subsequently tested and iterated. Outcomes: The findings provide the ICIM framework composed of five elements: Discipline Diversity Quadruple; Systematic Structure; Inspirational Stimuli; Supportive Collaboration Environment; and Hardware and Intellectual Support. The framework offers a discussion of the key elements when attempting to facilitate interdisciplinary collaboration for sustainability innovation. Contributions: This study contributes to two burgeoning areas of sustainable development and open innovation studies by articulating the concrete structure to bridge the gap. In practice, the framework helps facilitate effective innovation processes and positive social and environmental impact created for real-world sustainability challenges.

Keywords: action research, interdisciplinary collaboration, open innovation, problem-solving, sustainable development, sustainability challenges

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Authors: J. Martin, A. Dannenberg, G. Detrell, R. Ewald, S. Fasoulas

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Microalgae-based photobioreactors (PBR) for Life Support Systems (LSS) are currently being investigated for future space missions such as a crewed base on planets or moons. Biological components may help reducing resupply masses by closing material mass flows with the help of regenerative components. Via photosynthesis, the microalgae use CO₂, water, light and nutrients to provide oxygen and biomass for the astronauts. These capabilities could have synergies with Earth applications that tackle current problems and the developed technologies can be transferred. For example, a current worldwide discussed issue is the increased nitrate and phosphate pollution of ground water from agricultural waste waters. To investigate the potential use of a biological system based on the ability of the microalgae to extract and use nitrate and phosphate for the treatment of polluted ground water from agricultural applications, a scalable test stand is being developed. This test stand investigates the maximization of intake rates of nitrate and quantifies the produced biomass and oxygen. To minimize the required energy, for the uptake of nitrate from artificial waste water (AWW) the Flashing Light Effect (FLE) and the adaption of the illumination spectrum were realized. This paper describes the composition of the AWW, the development of the illumination unit and the possibility of non-invasive process optimization and control via the adaption of the illumination spectrum and illumination cycles. The findings were a doubling of the energy related growth rate by adapting the illumination setting.

Keywords: microalgae, illumination, nitrate uptake, flashing light effect

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Authors: Mustapha Saidu, Bilyaminu Mohammed

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The study was conducted in Udubo Grazing Reserve between July 2019 and October 2019 to assess forage utilization for pasture-based livestock production in reserve. The grazing land was cross-divided into grids, where 15 coordinates were selected as the sample points. Grids of one-kilometer interval were made. The grids were systematically selected 1 grid after 7 grids. 1 × 1-meter quadrat was made at the coordinate of the selected grids for measurement, estimation, and sample collection. The results of the study indicated that Zornia glochidiatah has the highest percent of species composition (42%), while Mitracarpus hirtus has the lowest percent (0.1%). Urochloa mosambicensis has 48 percent of height removed and 27 percent used by weight, Zornia glochidiata 60 percent of height removed and 57 percent used by weight, Alysicapus veginalis has 55 percent of height removed, and 40 percent used by weight, and Cenchrus biflorus has 40 percent of height removed and 28 percent used by weight. The target is 50 percent utilization of forage by weight during a grazing period as well as at the end of the grazing season. The study found that Orochloa mosambicensis, Alysicarpus veginalis, and Cenchrus biflorus had lower percent by weight which is normal, while Zornia glochidiata had a higher percent by weight which is an indication of danger. The study recommends that the identification of key plant species in pasture and rangeland is critical to implementing a successful grazing management plan. There should be collective action and promotion of historically generated grazing knowledge through public and private advocacies.

Keywords: forage, grazing reserve, live stock, pasture, plant species

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Authors: Rafal Stegierski, Krzysztof Dmitruk

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The paper focuses on robotic tele-presence system build around humanoid robot operated with controller-less Wizard of Oz technique. Proposed solution gives possibility to quick start acting as a operator with short, if any, initial training.

Keywords: robotics, motion capture, Wizard of Oz, humanoid robots, human robot interaction

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Authors: C. Q. Geng, Y. K. Hsiao

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We study direct CP-violating asymmetries (CPAs) in the baryonic B decays of B- -> p\bar{p}M and Λb decays of Λb ®pM andΛb -> J/ΨpM with M=π-, K-,ρ-,K*- based on the generalized factorization method in the standard model (SM). In particular, we show that the CPAs in the vector modes of B-®p\bar{p}K* and Λb -> p K*- can be as large as 20%. We also discuss the simplest purely baryonic decays of Λb-> p\bar{p}n, p\bar{p}Λ, Λ\bar{p}Λ, and Λ\bar{Λ}Λ. We point out that some of CPAs are promising to be measured by the current as well as future B facilities.

Keywords: CP violation, B decays, baryonic decays, Λb decays

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Authors: Ratih Fitria Putri, Josaphat Tetuko Sri Sumantyo, Hiroaki Kuze

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Jakarta Metropolitan City is located on the northwest coast of West Java province with geographical location between 106º33’ 00”-107º00’00”E longitude and 5º48’30”-6º24’00”S latitude. Jakarta urban area has been suffered from land subsidence in several land use type as trading, industry and settlement area. Land subsidence hazard is one of the consequences of urban development in Jakarta. This hazard is caused by intensive human activities in groundwater extraction and land use mismanagement. Geologically, the Jakarta urban area is mostly dominated by alluvium fan sediment. The objectives of this research are to make an analysis of Jakarta urban land use type on land subsidence zone areas. The process of producing safer land use and settlements of the land subsidence areas are very important. Spatial distributions of land subsidence detection are necessary tool for land use management planning. For this purpose, Differential Synthetic Aperture Radar Interferometry (DInSAR) method is used. The DInSAR is complementary to ground-based methods such as leveling and global positioning system (GPS) measurements, yielding information in a wide coverage area even when the area is inaccessible. The data were fine tuned by using X-Band image satellite data from 2010 to 2013 and land use mapping data. Our analysis of land use type that land subsidence movement occurred on the northern part Jakarta Metropolitan City varying from 7.5 to 17.5 cm/year as industry and settlement land use type areas.

Keywords: land use analysis, land subsidence mapping, urban area, X-band satellite image

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Authors: Alieh Farshbaf, Tayyeb Bahrami

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Introduction: Cc-chemokine receptor-5 (CCR5) is known as a main co-receptor in human immunodeficiency virus type-1 (HIV-1) infection. Many studies showed 32bp deletion (Δ32) in CCR5 gene, provide natural resistance to HIV-1 infection in homozygous individuals. Inducing the resistance mechanism by CCR5 in HIV-1 infected patients eliminated many problems of highly-active-anti retroviral therapy (HAART) drugs like as low safety, side-effects and virus rebounding from latent reservoirs. New treatments solved some restrictions that are based on gene modification and cell therapy. Literature review: The stories of the “Berlin and Boston patients” showed autologous hematopoietic stem cells transplantation (HSCT) could provide effective cure of HIV-1 infected patients. Furthermore, gene modification by zinc finger nuclease (ZFN) demonstrated another successful result again. Despite the other studies for gene therapy by ∆32 genotype, there is another mutation -CCR5 ∆32/m303- that provides HIV-1 resistant. It is a heterozygote genotype for ∆32 and T→A point mutation at nucleotide 303. These results approved the key role of CCR5 gene. Conclusion: Recent studies showed immune gene therapy and cell therapy could provide effective cure for refractory disease like as HIV. Eradication of HIV-1 from immune system was not observed by HAART, because of reloading virus genome from latent reservoirs after stopping them. It is showed that CCR5 could induce natural resistant to HIV-1 infection by the new approaches based on stem cell transplantation and gene modifying.

Keywords: CCR5, HIV-1, stem cell, immune gene therapy, gene modification

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Authors: T. Scattolin, E. Cavarzerani, F. Visentin, F. Rizzolio

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Organopalladium compounds have recently attracted attention for their high stability even under physiological conditions and, above all, for their remarkable in vitro cytotoxicity towards cisplatin-resistant cell lines. Among the organopalladium derivatives, those bearing at least one N-heterocyclic carbene ligand (NHC) and the Pd(II)-η³-allyl fragment have exhibited IC₅₀ values in the micro and sub-micromolar range towards several cancer cell lines in vitro and in some cases selectivity towards cancerous vs. non-tumorigenic cells. Herein, a selection of allyl and indenyl palladates were synthesized using a solvent-free method consisting of grinding the corresponding palladium precursors with different saturated and unsaturated azolium salts. All compounds have been fully characterized by NMR, XRD and elemental analyses. The intramolecular H, Cl interaction has been elucidated and quantified using the Voronoi Deformation Density scheme. Most of the complexes showed excellent cytotoxicity towards ovarian cancer cell lines, with I₅₀ values comparable to or even lower than cisplatin. Interestingly, the potent anticancer activity was also confirmed in a high-serous ovarian cancer (HGSOC) patient-derived tumoroid, with a clear superiority of this class of compounds over classical platinum-based agents. Finally, preliminary enzyme inhibition studies of the synthesized palladate complexes against the model TrxR show that the compounds have high activity comparable to or even higher than auranofin and classical Au(I) NHC complexes. Based on such promising data, further in vitro and in vivo experiments and in-depth mechanistic studies are ongoing in our laboratories.

Keywords: anticancer activity, palladium complexes, organoids, indenyl and allyl ligands

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