Search results for: Agilent’s Advanced Design System (ADS)
Commenced in January 2007
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Edition: International
Paper Count: 27616

Search results for: Agilent’s Advanced Design System (ADS)

15586 Topic Prominence and Temporal Encoding in Mandarin Chinese

Authors: Tzu-I Chiang

Abstract:

A central question for finite-nonfinite distinction in Mandarin Chinese is how does Mandarin encode temporal information without the grammatical contrast between past and present tense. Moreover, how do L2 learners of Mandarin whose native language is English and whose L1 system has tense morphology, acquire the temporal encoding system in L2 Mandarin? The current study reports preliminary findings on the relationship between topic prominence and the temporal encoding in L1 and L2 Chinese. Oral narratives data from 30 natives and learners of Mandarin Chinese were collected via a film-retell task. In terms of coding, predicates collected from the narratives were transcribed and then coded based on four major verb types: n-degree Statives (quality-STA), point-scale Statives (status-STA), n-atom EVENT (ACT), and point EVENT (resultative-ACT). How native speakers and non-native speakers started retelling the story was calculated. Results of the study show that native speakers of Chinese tend to express Topic Time (TT) syntactically at the topic position; whereas L2 learners of Chinese across levels rely mainly on the default time encoded in the event types. Moreover, as the proficiency level of the learner increases, learners’ appropriate use of the event predicates increased, which supports the argument that L2 development of temporal encoding is affected by lexical aspect.

Keywords: topic prominence, temporal encoding, lexical aspect, L2 acquisition

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15585 La₀.₈Ba₀.₂FeO₃ Perovskite as an Additive in the Three-Way Catalyst (TWCs) for Reduction of PGMs Loading

Authors: Mahshid Davoodpoor, Zahra Shamohammadi Ghahsareh, Saeid Razfar, Alaleh Dabbaghi

Abstract:

Nowadays, air pollution has become a topic of great concern all over the world. One of the main sources of air pollution is automobile exhaust gas, which introduces a large number of toxic gases, including CO, unburned hydrocarbons (HCs), NOx, and non-methane hydrocarbons (NMHCs), into the air. The application of three-way catalysts (TWCs) is still the most effective strategy to mitigate the emission of these pollutants. Due to the stringent environmental regulations which continuously become stricter, studies on the TWCs are ongoing despite several years of research and development. This arises from the washcoat complexity and the several numbers of parameters involved in the redox reactions. The main objectives of these studies are the optimization of washcoat formulation and the investigation of different coating modes. Perovskite (ABO₃), as a promising class of materials, has unique features that make it versatile to use as an alternative to commonly mixed oxides in washcoats. High catalytic activity for oxidation reactions and its relatively high oxygen storage capacity are important properties of perovskites in catalytic applications. Herein, La₀.₈Ba₀.₂FeO₃ perovskite material was synthesized using the co-precipitation method and characterized by XRD, ICP, and BET analysis. The effect of synthesis conditions, including B site metal (Fe and Co), metal precursor concentration, and dopant (Ba), were examined on the phase purity of the products. The selected perovskite sample was used as one of the components in the TWC formulation to evaluate its catalytic performance through Light-off, oxygen storage capacity, and emission analysis. Results showed a remarkable increment in oxygen storage capacity and also revealed that T50 and emission of CO, HC, and NOx reduced in the presence of perovskite structure which approves the enhancement of catalytic performance for the new washcoat formulation. This study shows the brilliant future of advanced oxide structures in the TWCs.

Keywords: Perovskite, three-way catalyst, PGMs, PGMs reduction

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15584 Black-Hole Dimension: A Distinct Methodology of Understanding Time, Space and Data in Architecture

Authors: Alp Arda

Abstract:

Inspired by Nolan's ‘Interstellar’, this paper delves into speculative architecture, asking, ‘What if an architect could traverse time to study a city?’ It unveils the ‘Black-Hole Dimension,’ a groundbreaking concept that redefines urban identities beyond traditional boundaries. Moving past linear time narratives, this approach draws from the gravitational dynamics of black holes to enrich our understanding of urban and architectural progress. By envisioning cities and structures as influenced by black hole-like forces, it enables an in-depth examination of their evolution through time and space. The Black-Hole Dimension promotes a temporal exploration of architecture, treating spaces as narratives of their current state interwoven with historical layers. It advocates for viewing architectural development as a continuous, interconnected journey molded by cultural, economic, and technological shifts. This approach not only deepens our understanding of urban evolution but also empowers architects and urban planners to create designs that are both adaptable and resilient. Echoing themes from popular culture and science fiction, this methodology integrates the captivating dynamics of time and space into architectural analysis, challenging established design conventions. The Black-Hole Dimension champions a philosophy that welcomes unpredictability and complexity, thereby fostering innovation in design. In essence, the Black-Hole Dimension revolutionizes architectural thought by emphasizing space-time as a fundamental dimension. It reimagines our built environments as vibrant, evolving entities shaped by the relentless forces of time, space, and data. This groundbreaking approach heralds a future in architecture where the complexity of reality is acknowledged and embraced, leading to the creation of spaces that are both responsive to their temporal context and resilient against the unfolding tapestry of time.

Keywords: black-hole, timeline, urbanism, space and time, speculative architecture

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15583 Secured Cancer Care and Cloud Services in Internet of Things /Wireless Sensor Network Based Medical Systems

Authors: Adeniyi Onasanya, Maher Elshakankiri

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In recent years, the Internet of Things (IoT) has constituted a driving force of modern technological advancement, and it has become increasingly common as its impacts are seen in a variety of application domains, including healthcare. IoT is characterized by the interconnectivity of smart sensors, objects, devices, data, and applications. With the unprecedented use of IoT in industrial, commercial and domestic, it becomes very imperative to harness the benefits and functionalities associated with the IoT technology in (re)assessing the provision and positioning of healthcare to ensure efficient and improved healthcare delivery. In this research, we are focusing on two important services in healthcare systems, which are cancer care services and business analytics/cloud services. These services incorporate the implementation of an IoT that provides solution and framework for analyzing health data gathered from IoT through various sensor networks and other smart devices in order to improve healthcare delivery and to help health care providers in their decision-making process for enhanced and efficient cancer treatment. In addition, we discuss the wireless sensor network (WSN), WSN routing and data transmission in the healthcare environment. Finally, some operational challenges and security issues with IoT-based healthcare system are discussed.

Keywords: IoT, smart health care system, business analytics, (wireless) sensor network, cancer care services, cloud services

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15582 The Role of Vernacular Radio Stations in Enhancing Agricultural Development in Kenya; A Case of KASS FM

Authors: Thomas Kipkurgat, Silahs Chemwaina

Abstract:

Communication and ICT is a crucial component in realization of vision 2030, radio has played a key role in dissemination of information to mass audience. Since time immemorial, mass media has played a vital role in passing information on agricultural development issues both locally and internationally. This paper aimed at assessing the role of community radio stations in enhancing agricultural development in Kenya. The paper sought to identify the main contributions of KASS FM radio in the agricultural development especially in rural areas, the study also aimed to establish the appropriate adjustments in editorial policies of KASS FM radio in helping to promote agricultural development related programmes in rural areas. Despite some weaknesses in radio programming and the mode of interaction with the rural people, the findings of this study showed that the rural communities are better off today than in the old days when FM radios were non-existent. KASS FM has come up with different developmental programmes that have positively contributed to changing the rural people’s ways of life. These programmes include farming, health, marital values, environment, cultural issues, human rights, democracy, religious teachings, peace and reconciliation. Such programmes feature experts, professionals and opinion leaders who address numerous topics of interest to the community. The local people participate in the production of these programmes through letters to the editor, and phone-ins, among others. Programmes such as political talk shows, which feature in KASS FM, has become one of the most important ways of community participation. The interpretation and conclusions are based on the empirical data analysis and the theories of development advanced by international development communication scholars, as presented in the paper. The study ends with some recommendations on how KASS FM can best serve the interests of the poor people in rural areas, and helps improve their lives.

Keywords: agriculture, development, communication, KASS FM, radio, rural areas, Kenya

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15581 Assessing the Role of Failed-ADR in Civil Litigation

Authors: Masood Ahmed

Abstract:

There is a plethora of literature (including judicial and extra-judicial comments) concerning the virtues of alternative dispute resolution processes within the English civil justice system. Lord Woolf in his Access to Justice Report ushered in a new pro-ADR philosophy and this was reinforced by Sir Rupert Jackson in his review of civil litigation costs. More recently, Briggs LJ, in his review of the Chancery Court, reiterated the significant role played by ADR and the need for better integration of ADR processes within the Chancery Court. His Lordship also noted that ADR which had failed to produce a settlement (i.e. a failed-ADR) continued to play a significant role in contributing to a ‘substantial narrowing of the issues or increased focus on the key issues’ which were ‘capable of assisting both the parties and the court in the economical determination of the dispute at trial.’ With the assistance of empirical data, this paper investigates the nature of failed-ADR and, in particular, assesses the effectiveness of failed-ADR processes as a tool in: (a) narrowing the legal and/or factual issues which may assist the courts in more effective and efficient case management of the dispute; (b) assisting the parties in the future settlement of the matter. This paper will also measure the effectiveness of failed-ADR by considering the views and experiences of legal practitioners who have engaged in failed-ADR.

Keywords: English civil justice system, alternative dispute resolution processes, civil court process, empirical data from legal profession regarding failed ADR

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15580 Mitigation of Risk Management Activities towards Accountability into Microfinance Environment: Malaysian Case Study

Authors: Nor Azlina A. Rahman, Jamaliah Said, Salwana Hassan

Abstract:

Prompt changes in global business environment, such as passionate competition, managerial/operational, changing governmental regulation and innovation in technology have significant impacts on the organizations. At present, global business environment demands for more proactive institutions on microfinance to provide an opportunity for the business success. Microfinance providers in Malaysia still accelerate its activities of funding by cash and cheque. These institutions are at high risk as the paper-based system is deemed to be slow and prone to human error, as well as requiring a major annual reconciliation process. The global transformation of financial services, growing involvement of technology, innovation and new business activities had progressively made risk management profile to be more subjective and diversified. The persistent, complex and dynamic nature of risk management activities in the institutions arise due to highly automated advancements of technology. This may thus manifest in a variety of ways throughout the financial services sector. This study seeks out to examine current operational risks management being experienced by microfinance providers in Malaysia; investigate the process of current practices on facilitator control factor mechanisms, and explore how the adoption of technology, innovation and use of management accounting practices would affect the risk management process of operation system in microfinance providers in Malaysia. A case study method was employed in this study. The case study also need to find that the vital past role of management accounting will be used for mitigation of risk management activities towards accountability as an information or guideline to microfinance provider. An empirical element obtainable with qualitative method is needed in this study, where multipart and in-depth information are essential to understand the issues of these institution phenomena. This study is expected to propose a theoretical model for implementation of technology, innovation and management accounting practices into the system of operation to improve internal control and subsequently lead to mitigation of risk management activities among microfinance providers to be more successful.

Keywords: microfinance, accountability, operational risks, management accounting practices

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15579 Sustainable Development Change within Our Environs

Authors: Akinwale Adeyinka

Abstract:

Critical natural resources such as clean ground water, fertile topsoil, and biodiversity are diminishing at an exponential rate, orders of magnitude above that at which they can be regenerated. Based on news on world population record, over 6 billion people on earth, and almost a quarter million added each day, the scale of human activity and environmental impact is unprecedented. Soaring human population growth over the past century has created a visible challenge to earth’s life support systems. In addition, the world faces an onslaught of other environmental threats including degenerated global climate change, global warming, intensified acid rain, stratospheric ozone depletion and health threatening pollution. Overpopulation and the use of deleterious technologies combine to increase the scale of human activities to a level that underlies these entire problems. These intensifying trends cannot continue indefinitely, hopefully, through increased understanding and valuation of ecosystems and their services, earth’s basic life-support system will be protected for the future.To say the fact, human civilization is now the dominant cause of change in the global environment. Now that our relationship to the earth has change so utterly, we have to see that change and understand its implication. These are actually 2 aspects to the challenges which we should believe. The first is to realize that our power to harm the earth can indeed have global and even permanent effects. Second is to realize that the only way to understand our new role as a co-architect of nature is to see ourselves as part of a complex system that does operate according to the same simple rules of cause and effect we are used to. So understanding the physical/biological dimension of earth system is an important precondition for making sensible policy to protect our environment. Because we believe Sustainable Development Is a matter of reconciling respect for the environment, social equity and economic profitability. Also, we strongly believe that environmental protection is naturally about reducing air and water pollution, but it also includes the improvement of the environmental performance of existing process. That is why we should always have it at the heart of our business that the environmental problem is not our effect on the environment so much as our relationship with the environment. We should always think of being environmental friendly in our operation.

Keywords: Stratospheric ozone depletion ion , Climate Change, global warming, social equity and economic profitability

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15578 Bilingual Experience Influences Different Components of Cognitive Control: Evidence from fMRI Study

Authors: Xun Sun, Le Li, Ce Mo, Lei Mo, Ruiming Wang, Guosheng Ding

Abstract:

Cognitive control plays a central role in information processing, which is comprised of various components including response suppression and inhibitory control. Response suppression is considered to inhibit the irrelevant response during the cognitive process; while inhibitory control to inhibit the irrelevant stimulus in the process of cognition. Both of them undertake distinct functions for the cognitive control, so as to enhance the performances in behavior. Among numerous factors on cognitive control, bilingual experience is a substantial and indispensible factor. It has been reported that bilingual experience can influence the neural activity of cognitive control as whole. However, it still remains unknown how the neural influences specifically present on the components of cognitive control imposed by bilingualism. In order to explore the further issue, the study applied fMRI, used anti-saccade paradigm and compared the cerebral activations between high and low proficient Chinese-English bilinguals. Meanwhile, the study provided experimental evidence for the brain plasticity of language, and offered necessary bases on the interplay between language and cognitive control. The results showed that response suppression recruited the middle frontal gyrus (MFG) in low proficient Chinese-English bilinguals, but the inferior patrietal lobe in high proficient Chinese-English bilinguals. Inhibitory control engaged the superior temporal gyrus (STG) and middle temporal gyrus (MTG) in low proficient Chinese-English bilinguals, yet the right insula cortex was more active in high proficient Chinese-English bilinguals during the process. These findings illustrate insights that bilingual experience has neural influences on different components of cognitive control. Compared with low proficient bilinguals, high proficient bilinguals turn to activate advanced neural areas for the processing of cognitive control. In addition, with the acquisition and accumulation of language, language experience takes effect on the brain plasticity and changes the neural basis of cognitive control.

Keywords: bilingual experience, cognitive control, inhibition control, response suppression

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15577 Comparison of Catalyst Support for High Pressure Reductive Amination

Authors: Tz-Bang Du, Cheng-Han Hsieh, Li-Ping Ju, Hung-Jie Liou

Abstract:

Polyether amines synthesize by secondary hydroxyl polyether diol play an important role in epoxy hardener. The low molecular weight product is used in low viscosity and high transparent polyamine product for the logo, ground cover, especially for wind turbine blade, while the high molecular weight products are used in advanced agricultures such as a high-speed railway. High-pressure reductive amination process is required for producing these amines. In the condition of higher than 150 atm pressure and 200 degrees Celsius temperature, supercritical ammonia is used as a reactant and also a solvent. It would be a great challenge to select a catalyst support for such high-temperature alkaline circumstance. In this study, we have established a six-autoclave-type (SAT) high-pressure reactor for amination catalyst screening, which six experiment conditions with different temperature and pressure could be examined at the same time. We synthesized copper-nickel catalyst on different shaped alumina catalyst support and evaluated the catalyst activity for high-pressure reductive amination of polypropylene glycol (PPG) by SAT reactor. Ball type gamma alumina, ball type activated alumina and pellet type gamma alumina catalyst supports are evaluated in this study. Gamma alumina supports have shown better activity on PPG reductive amination than activated alumina support. In addition, the catalysts are evaluated in fixed bed reactor. The diamine product was successfully synthesized via this catalyst and the strength of the catalysts is measured. The crush strength of blank supports is about 13.5 lb for both gamma alumina and activated alumina. The strength increases to 20.3 lb after synthesized to be copper-nickel catalyst. After test in the fixed bed high-pressure reductive amination process for 100 hours, the crush strength of the used catalyst is 3.7 lb for activated alumina support, 12.0 lb for gamma alumina support. The gamma alumina is better than activated alumina to use as catalyst support in high-pressure reductive amination process.

Keywords: high pressure reductive amination, copper nickel catalyst, polyether amine, alumina

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15576 Process Modeling in an Aeronautics Context

Authors: Sophie Lemoussu, Jean-Charles Chaudemar, Robertus A. Vingerhoeds

Abstract:

Many innovative projects exist in the field of aeronautics, each addressing specific areas so to reduce weight, increase autonomy, reduction of CO2, etc. In many cases, such innovative developments are being carried out by very small enterprises (VSE’s) or small and medium sized-enterprises (SME’s). A good example concerns airships that are being studied as a real alternative to passenger and cargo transportation. Today, no international regulations propose a precise and sufficiently detailed framework for the development and certification of airships. The absence of such a regulatory framework requires a very close contact with regulatory instances. However, VSE’s/SME’s do not always have sufficient resources and internal knowledge to handle this complexity and to discuss these issues. This poses an additional challenge for those VSE’s/SME’s, in particular those that have system integration responsibilities and that must provide all the necessary evidence to demonstrate their ability to design, produce, and operate airships with the expected level of safety and reliability. The main objective of this research is to provide a methodological framework enabling VSE’s/SME’s with limited resources to organize the development of airships while taking into account the constraints of safety, cost, time and performance. This paper proposes to provide a contribution to this problematic by proposing a Model-Based Systems Engineering approach. Through a comprehensive process modeling approach applied to the development processes, the regulatory constraints, existing best practices, etc., a good image can be obtained as to the process landscape that may influence the development of airships. To this effect, not only the necessary regulatory information is taken on board, also other international standards and norms on systems engineering and project management are being modeled and taken into account. In a next step, the model can be used for analysis of the specific situation for given developments, derive critical paths for the development, identify eventual conflicting aspects between the norms, standards, and regulatory expectations, or also identify those areas where not enough information is available. Once critical paths are known, optimization approaches can be used and decision support techniques can be applied so to better support VSE’s/SME’s in their innovative developments. This paper reports on the adopted modeling approach, the retained modeling languages, and how they all fit together.

Keywords: aeronautics, certification, process modeling, project management, regulation, SME, systems engineering, VSE

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15575 An Evaluation of a Prototype System for Harvesting Energy from Pressurized Pipeline Networks

Authors: Nicholas Aerne, John P. Parmigiani

Abstract:

There is an increasing desire for renewable and sustainable energy sources to replace fossil fuels. This desire is the result of several factors. First, is the role of fossil fuels in climate change. Scientific data clearly shows that global warming is occurring. It has also been concluded that it is highly likely human activity; specifically, the combustion of fossil fuels, is a major cause of this warming. Second, despite the current surplus of petroleum, fossil fuels are a finite resource and will eventually become scarce and alternatives, such as clean or renewable energy will be needed. Third, operations to obtain fossil fuels such as fracking, off-shore oil drilling, and strip mining are expensive and harmful to the environment. Given these environmental impacts, there is a need to replace fossil fuels with renewable energy sources as a primary energy source. Various sources of renewable energy exist. Many familiar sources obtain renewable energy from the sun and natural environments of the earth. Common examples include solar, hydropower, geothermal heat, ocean waves and tides, and wind energy. Often obtaining significant energy from these sources requires physically-large, sophisticated, and expensive equipment (e.g., wind turbines, dams, solar panels, etc.). Other sources of renewable energy are from the man-made environment. An example is municipal water distribution systems. The movement of water through the pipelines of these systems typically requires the reduction of hydraulic pressure through the use of pressure reducing valves. These valves are needed to reduce upstream supply-line pressures to levels suitable downstream users. The energy associated with this reduction of pressure is significant but is currently not harvested and is simply lost. While the integrity of municipal water supplies is of paramount importance, one can certainly envision means by which this lost energy source could be safely accessed. This paper provides a technical description and analysis of one such means by the technology company InPipe Energy to generate hydroelectricity by harvesting energy from municipal water distribution pressure reducing valve stations. Specifically, InPipe Energy proposes to install hydropower turbines in parallel with existing pressure reducing valves in municipal water distribution systems. InPipe Energy in partnership with Oregon State University has evaluated this approach and built a prototype system at the O. H. Hinsdale Wave Research Lab. The Oregon State University evaluation showed that the prototype system rapidly and safely initiates, maintains, and ceases power production as directed. The outgoing water pressure remained constant at the specified set point throughout all testing. The system replicates the functionality of the pressure reducing valve and ensures accurate control of down-stream pressure. At a typical water-distribution-system pressure drop of 60 psi the prototype, operating at an efficiency 64%, produced approximately 5 kW of electricity. Based on the results of this study, this proposed method appears to offer a viable means of producing significant amounts of clean renewable energy from existing pressure reducing valves.

Keywords: pressure reducing valve, renewable energy, sustainable energy, water supply

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15574 Design and Development of Engine Valve Train Wear Test Rig for the Assessment of Valve Train Tribochemistry

Authors: V. Manjunath, C. V. Chandrashekara

Abstract:

Ecosystem authority calls for the use of lubricants with less effect on the nature in terms of exhaust emission, while engine user demands more mileage per liter of fuel without any compromise on engine durability. From this viewpoint, engine manufacturers require the optimum combination of materials and lubricant additive package to minimize friction and wear in the engine components like piston, crankshaft and valve train etc. The demands are placed for requirements to operate at higher speeds, loads, temperature and for extended replacement intervals of engine oil. Besides, it is necessary to accurately predict the lubricant life or the replacement interval to prevent lubrication and valve-train components failure. Experimental tribology evaluation of new engine oils requires large amount of time and energy. Hence low cost bench test is necessary for industries and original equipment manufacturing companies (OEM) to study the performance of lubricants. The present work outlines the procedure for the design and development of a valve train wear rig (MCR) to simulate the ASTMD-6891 and to develop new engine test for Indian automobile sector to evaluate lubricants for Indian automobile market. In order to improve the lubrication between cam and follower of internal combustion engine, the influence of materials or oils viscosity and additives on the friction and wear characteristics are examined with test rig by increasing the contact load at two different revolution speed. From the experimentation following results are made obvious. Temperature, Torque, speed and wear plots are used to validate the data obtained from the newly developed multi-cam cam rig (MCR) with follower against a cast iron camshaft. Camshaft lobe wear is measured at seven different locations on cam profile. Tribofilm formed using 5W-30 oil is evaluated and correlated with the standard test results.

Keywords: ASTMD-6891, multi-cam rig (MCR), 5W-30, cam-profile

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15573 Application of a Lighting Design Method Using Mean Room Surface Exitance

Authors: Antonello Durante, James Duff, Kevin Kelly

Abstract:

The visual needs of people in modern work based buildings are changing. Self-illuminated screens of computers, televisions, tablets and smart phones have changed the relationship between people and the lit environment. In the past, lighting design practice was primarily based on providing uniform horizontal illuminance on the working plane, but this has failed to ensure good quality lit environments. Lighting standards of today continue to be set based upon a 100 year old approach that at its core, considers the task illuminance of the utmost importance, with this task typically being located on a horizontal plane. An alternative method focused on appearance has been proposed, as opposed to the traditional performance based approach. Mean Room Surface Exitance (MRSE) and Target-Ambient Illuminance Ratio (TAIR) are two new metrics proposed to assess illumination adequacy in interiors. The hypothesis is that these factors will be superior to the existing metrics used, which are horizontal illuminance led. For the six past years, research has examined this, within the Dublin Institute of Technology, with a view to determining the suitability of this approach for application to general lighting practice. Since the start of this research, a number of key findings have been produced that centered on how occupants will react to various levels of MRSE. This paper provides a broad update on how this research has progressed. More specifically, this paper will: i) Demonstrate how MRSE can be measured using HDR images technology, ii) Illustrate how MRSE can be calculated using scripting and an open source lighting computation engine, iii) Describe experimental results that demonstrate how occupants have reacted to various levels of MRSE within experimental office environments.

Keywords: illumination hierarchy (IH), mean room surface exitance (MRSE), perceived adequacy of illumination (PAI), target-ambient illumination ratio (TAIR)

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15572 Infilling Strategies for Surrogate Model Based Multi-disciplinary Analysis and Applications to Velocity Prediction Programs

Authors: Malo Pocheau-Lesteven, Olivier Le Maître

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Engineering and optimisation of complex systems is often achieved through multi-disciplinary analysis of the system, where each subsystem is modeled and interacts with other subsystems to model the complete system. The coherence of the output of the different sub-systems is achieved through the use of compatibility constraints, which enforce the coupling between the different subsystems. Due to the complexity of some sub-systems and the computational cost of evaluating their respective models, it is often necessary to build surrogate models of these subsystems to allow repeated evaluation these subsystems at a relatively low computational cost. In this paper, gaussian processes are used, as their probabilistic nature is leveraged to evaluate the likelihood of satisfying the compatibility constraints. This paper presents infilling strategies to build accurate surrogate models of the subsystems in areas where they are likely to meet the compatibility constraint. It is shown that these infilling strategies can reduce the computational cost of building surrogate models for a given level of accuracy. An application of these methods to velocity prediction programs used in offshore racing naval architecture further demonstrates these method's applicability in a real engineering context. Also, some examples of the application of uncertainty quantification to field of naval architecture are presented.

Keywords: infilling strategy, gaussian process, multi disciplinary analysis, velocity prediction program

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15571 Reactors with Effective Mixing as a Solutions for Micro-Biogas Plant

Authors: M. Zielinski, M. Debowski, P. Rusanowska, A. Glowacka-Gil, M. Zielinska, A. Cydzik-Kwiatkowska, J. Kazimierowicz

Abstract:

Technologies for the micro-biogas plant with heating and mixing systems are presented as a part of the Research Coordination for a Low-Cost Biomethane Production at Small and Medium Scale Applications (Record Biomap). The main objective of the Record Biomap project is to build a network of operators and scientific institutions interested in cooperation and the development of promising technologies in the sector of small and medium-sized biogas plants. The activities carried out in the project will bridge the gap between research and market and reduce the time of implementation of new, efficient technological and technical solutions. Reactor with simultaneously mixing and heating system is a concrete tank with a rectangular cross-section. In the reactor, heating is integrated with the mixing of substrate and anaerobic sludge. This reactor is solution dedicated for substrates with high solids content, which cannot be introduced to the reactor with pumps, even with positive displacement pumps. Substrates are poured to the reactor and then with a screw pump, they are mixed with anaerobic sludge. The pumped sludge, flowing through the screw pump, is simultaneously heated by a heat exchanger. The level of the fermentation sludge inside the reactor chamber is above the bottom edge of the cover. Cover of the reactor is equipped with the screw pump driver. Inside the reactor, an electric motor is installed that is driving a screw pump. The heated sludge circulates in the digester. The post-fermented sludge is collected using a drain well. The inlet to the drain well is below the level of the sludge in the digester. The biogas is discharged from the reactor by the biogas intake valve located on the cover. The technology is very useful for fermentation of lignocellulosic biomass and substrates with high content of dry mass (organic wastes). The other technology is a reactor for micro-biogas plant with a pressure mixing system. The reactor has a form of plastic or concrete tank with a circular cross-section. The effective mixing of sludge is ensured by profiled at 90° bottom of the tank. Substrates for fermentation are supplied by an inlet well. The inlet well is equipped with a cover that eliminates odour release. The introduction of a new portion of substrates is preceded by pumping of digestate to the disposal well. Optionally, digestate can gravitationally flow to digestate storage tank. The obtained biogas is discharged into the separator. The valve supplies biogas to the blower. The blower presses the biogas from the fermentation chamber in such a way as to facilitate the introduction of a new portion of substrates. Biogas is discharged from the reactor by valve that enables biogas removal but prevents suction from outside the reactor.

Keywords: biogas, digestion, heating system, mixing system

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15570 Trends, Attitude, and Knowledge about the Methods of Labour Pain Management among Polish Women

Authors: Kinga Zebrowska, Maria Falis, Katarzyna Kosinska-Kaczynska, Bartosz Godek, Olga Plaza, Katarzyna Kwiatkowska

Abstract:

Introduction: According to the ministerial decree of 16 August 2018, each woman in Poland during childbirth has the right to the pharmacological and non-pharmacological labour pain management (LPM). Aim: The aim of the study was to assess the knowledge of Polish mothers about pharmacological and non-pharmacological LPM, to investigate which methods they chose and their satisfaction with chosen ones. Material And Methods: A prospective cross-sectional study was performed among women who gave birth between 2015 and 2018. The self-composed questionnaire was distributed via the Internet in October 2018. Results: 13.727 women participated in the study. 75% have learned about LPM from the Internet. 68% of them did not gain any information on LPM from doctors during their prenatal appointments Safety of the newborn (46%), midwife’s advice (40%) and the chance of the immediate pain relief (39%) were the most important issues while choosing LPM. Respondents used a wide range of non-pharmacological methods, such as the assistance of partner during labour (81%), physical activity (58%), immersion in water (37%), relaxation techniques (15%) and others. 11% of mothers did not use any of the LPM methods. 52% of women declared that they wanted to use the pharmacological anaesthesia, while 49% had it performed (28% epidural, 16% inhaled anaesthesia, 5% parenteral opioids). Pharmacological methods were unavailable due to lack of anaesthesiologist in the maternity ward (41%) or inaccessibility of the chosen methods in the hospital (31%) and too advanced labour (43%). 48% of respondents did not decide to use pharmacological methods, because the pain was bearable (29%), anxiety of child’s health (17%), or belief that the pain is natural and it should not be avoided (16%). 83% of respondents believed that epidural analgesia has no influence on the time needed to gain a full cervix dilatation and 81% of them claimed that serious spinal cord injury is a common side effect of epidural. 51% believed that epidural increases the risk of caesarean section. Conclusions: The knowledge about the methods of LPM is not satisfactory. We should focus on well- maintained education guided by doctors, midwives, and media.

Keywords: childbirth, labour pain management, maternity experiences, obstetrics

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15569 Structural, Vibrational, Magnetic, and Electronic Properties of La₂MMnO₆ Double Perovskites with M = Ni, Co, and Zn

Authors: Hamza Ouachtouk, Amine Harbi, Said Azerblou, Youssef Naimi, El Mostafa Tace

Abstract:

This study delves into the structural, vibrational, magnetic, and electronic properties of La₂MMnO₆ double perovskites, where M denotes Ni, Co, and Zn. Recognized for their versatile ionic configurations within the A and B sub-lattices, double perovskite oxides have attracted considerable interest due to their extensive array of physical properties, which include multiferroic behavior, colossal magnetoresistance, and ferroelectric/piezoelectric functionalities. These materials are pivotal for energy-related technologies like solid oxide fuel cells and water-splitting catalysis, attributed to their superior oxygen ion transport and storage capabilities. This research places particular emphasis on La₂NiMnO₆ and La₂CoMnO₆, known for their distinct magnetic, electric, and multiferroic properties, and extends the investigation to La₂ZnMnO₆, synthesized via high-temperature solid-state chemistry. This addition aims to ascertain the impact of zinc substitution on these properties. Structural analysis through X-ray diffraction has confirmed a monoclinic structure within the P2₁/n space group. Comprehensive vibrational studies utilizing infrared and Raman spectroscopy, alongside additional XRD assessments, provide a detailed examination of the dynamic and electronic behaviors of these compounds. The results underscore the significant role of chemical composition in modulating their functional properties. Comparatively, this study highlights that zinc substitution notably alters the electronic and magnetic responses, which could enhance the applicability of these materials in advanced energy technologies. This expanded analysis not only reinforces our understanding of La₂MMnO₆'s physical characteristics but also highlights its potential applications in the next generation of energy solutions.

Keywords: double perovskites, structural analysis, vibrational spectroscopy, magnetic properties, electronic properties, high-temperature solid-state chemistry, La₂MMnO₆, monoclinic structure, x-ray diffraction

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15568 Tribological Aspects of Advanced Roll Material in Cold Rolling of Stainless Steel

Authors: Mohammed Tahir, Jonas Lagergren

Abstract:

Vancron 40, a nitrided powder metallurgical tool Steel, is used in cold work applications where the predominant failure mechanisms are adhesive wear or galling. Typical applications of Vancron 40 are among others fine blanking, cold extrusion, deep drawing and cold work rolls for cluster mills. Vancron 40 positive results for cold work rolls for cluster mills and as a tool for some severe metal forming process makes it competitive compared to other type of work rolls that require higher precision, among others in cold rolling of thin stainless steel, which required high surface finish quality. In this project, three roll materials for cold rolling of stainless steel strip was examined, Vancron 40, Narva 12B (a high-carbon, high-chromium tool steel alloyed with tungsten) and Supra 3 (a Chromium-molybdenum tungsten-vanadium alloyed high speed steel). The purpose of this project was to study the depth profiles of the ironed stainless steel strips, emergence of galling and to study the lubrication performance used by steel industries. Laboratory experiments were conducted to examine scratch of the strip, galling and surface roughness of the roll materials under severe tribological conditions. The critical sliding length for onset of galling was estimated for stainless steel with four different lubricants. Laboratory experiments result of performance evaluation of resistance capability of rolls toward adhesive wear under severe conditions for low and high reductions. Vancron 40 in combination with cold rolling lubricant gave good surface quality, prevents galling of metal surfaces and good bearing capacity.

Keywords: Vancron 40, cold rolling, adhesive wear, galling, surface finish, lubricant, stainless steel

Procedia PDF Downloads 518
15567 A Leadership Approach for the Sake of Organizations: Human-Oriented Leadership

Authors: Eser Bingül

Abstract:

The leadership and leaders, also having been a privileged subject of scientific researches in the last century, have become influential in shaping the destiny of the states since the first examples of the warfare history. The issue of leadership, finding a place in the management science, can also be defined as an integration of function within the aspect of leader. In this description, the relationship has come to the foreground which is established between the development of leadership theories and the elements of function which are leader, followers, and condition. While one reason of this analysis in leadership is to keep a lens to the historical background, the main reason has been a questioning the traits and education of leaders who have still affected the nation’s and organization’s fate. The links and analysis established in the definition of leadership have put forward the necessity of solving the unpredictable structure of human nature and behaviors in the focus of leadership approach. On the other hand becoming a model that meets the today’s needs of any system has given a clue that the leaders should turn towards the people. Being aware of this necessity, human-oriented leadership approach aims to gain both followers and their abilities to the system with giving them a deserved esteem and create the team spirit based on mutual trust. Ultimately this approach, with the determined leadership qualities consisting of charisma, ability of communication and trust, will be able to produce the solutions to the instant and long-term problems and uncertainties, derived from the variables of function, for the sake of systems.

Keywords: human nature, leadership, human-oriented approach, social sciences and humanities

Procedia PDF Downloads 309
15566 Teachers’ Role and Principal’s Administrative Functions as Correlates of Effective Academic Performance of Public Secondary School Students in Imo State, Nigeria

Authors: Caroline Nnokwe, Iheanyi Eneremadu

Abstract:

Teachers and principals are vital and integral parts of the educational system. For educational objectives to be met, the role of teachers and the functions of the principals are not to be overlooked. However, the inability of teachers and principals to carry out their roles effectively has impacted the outcome of the students’ performance. The study, therefore, examined teachers’ roles and principal’s administrative functions as correlates of effective academic performance of public secondary school students in Imo state, Nigeria. Four research questions and two hypotheses guided the study. The study adopted a correlation research design. The sample size was 5,438 respondents via the Yaro-Yamane technique, which consists of 175 teachers, 13 principals and 5,250 students using the proportional stratified random sampling technique. The instruments for data collection were a researcher-made questionnaire titled Teachers’ Role/Principals’ Administrative Functions Questionnaire (TRPAFQ) with a Cronbach Alpha coefficient of .82 and student's internal results obtained from the school authorities. Data collected were analyzed using the Pearson product-moment correlation coefficient and simple linear regression. Research questions were answered using Pearson Product Moment Correlation statistics, while the hypotheses were tested at 0.05 level of significance using regression analysis. The findings of the study showed that the educational qualification of teachers, organizing, and planning correlated student’s academic performance to a great extent, while availability and proper use of instructional materials by teachers correlated the academic performance of students to a very high extent. The findings also revealed that there is a significant relationship between teachers’ role, principals’ administrative functions and student’s academic performance of public secondary schools in Imo State, The study recommended among others that there is the need for government, through the ministry of education, and education authorities to adequately staff their supervisory department in order to carry out proper supervision of secondary school teachers, and also provide adequate instructional materials to ensure greater academic performance among secondary school students of Imo state, Nigeria.

Keywords: instructional materials, principals’ administrative functions, students’ academic performance, teacher role

Procedia PDF Downloads 71
15565 Enhanced Kinetic Solubility Profile of Epiisopiloturine Solid Solution in Hipromellose Phthalate

Authors: Amanda C. Q. M. Vieira, Cybelly M. Melo, Camila B. M. Figueirêdo, Giovanna C. R. M. Schver, Salvana P. M. Costa, Magaly A. M. de Lyra, Ping I. Lee, José L. Soares-Sobrinho, Pedro J. Rolim-Neto, Mônica F. R. Soares

Abstract:

Epiisopiloturine (EPI) is a drug candidate that is extracted from Pilocarpus microphyllus and isolated from the waste of Pilocarpine. EPI has demonstrated promising schistosomicidal, leishmanicide, anti-inflammatory and antinociceptive activities, according to in vitro studies that have been carried out since 2009. However, this molecule shows poor aqueous solubility, which represents a problem for the release of the drug candidate and its absorption by the organism. The purpose of the present study is to investigate the extent of enhancement of kinetic solubility of a solid solution (SS) of EPI in hipromellose phthalate HP-55 (HPMCP), an enteric polymer carrier. SS was obtained by the solvent evaporation methodology, using acetone/methanol (60:40) as solvent system. Both EPI and polymer (drug loading 10%) were dissolved in this solvent until a clear solution was obtained, and then dried in oven at 60ºC during 12 hours, followed by drying in a vacuum oven for 4 h. The results show a considerable modification in the crystalline structure of the drug candidate. For instance, X-ray diffraction (XRD) shows a crystalline behavior for the EPI, which becomes amorphous for the SS. Polarized light microscopy, a more sensitive technique than XRD, also shows completely absence of crystals in SS sample. Differential Scanning Calorimetric (DSC) curves show no signal of EPI melting point in SS curve, indicating, once more, no presence of crystal in this system. Interaction between the drug candidate and the polymer were found in Infrared microscopy, which shows a carbonyl 43.3 cm-1 band shift, indicating a moderate-strong interaction between them, probably one of the reasons to the SS formation. Under sink conditions (pH 6.8), EPI SS had its dissolution performance increased in 2.8 times when compared with the isolated drug candidate. EPI SS sample provided a release of more than 95% of the drug candidate in 15 min, whereas only 45% of EPI (alone) could be dissolved in 15 min and 70% in 90 min. Thus, HPMCP demonstrates to have a good potential to enhance the kinetic solubility profile of EPI. Future studies to evaluate the stability of SS are required to conclude the benefits of this system.

Keywords: epiisopiloturine, hipromellose phthalate HP-55, pharmaceuticaltechnology, solubility

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15564 A Case Study on Performance of Isolated Bridges under Near-Fault Ground Motion

Authors: Daniele Losanno, H. A. Hadad, Giorgio Serino

Abstract:

This paper presents a numerical investigation on the seismic performance of a benchmark bridge with different optimal isolation systems under near fault ground motion. Usually, very large displacements make seismic isolation an unfeasible solution due to boundary conditions, especially in case of existing bridges or high risk seismic regions. Hence, near-fault ground motions are most likely to affect either structures with long natural period range like isolated structures or structures sensitive to velocity content such as viscously damped structures. The work is aimed at analyzing the seismic performance of a three-span continuous bridge designed with different isolation systems having different levels of damping. The case study was analyzed in different configurations including: (a) simply supported, (b) isolated with lead rubber bearings (LRBs), (c) isolated with rubber isolators and 10% classical damping (HDLRBs), and (d) isolated with rubber isolators and 70% supplemental damping ratio. Case (d) represents an alternative control strategy that combines the effect of seismic isolation with additional supplemental damping trying to take advantages from both solutions. The bridge is modeled in SAP2000 and solved by time history direct-integration analyses under a set of six recorded near-fault ground motions. In addition to this, a set of analysis under Italian code provided seismic action is also conducted, in order to evaluate the effectiveness of the suggested optimal control strategies under far field seismic action. Results of the analysis demonstrated that an isolated bridge equipped with HDLRBs and a total equivalent damping ratio of 70% represents a very effective design solution for both mitigation of displacement demand at the isolation level and base shear reduction in the piers also in case of near fault ground motion.

Keywords: isolated bridges, near-fault motion, seismic response, supplemental damping, optimal design

Procedia PDF Downloads 274
15563 Designing a Syllabus for an Academic Writing Course Instruction Based on Students' Needs

Authors: Nuur Insan Tangkelangi

Abstract:

Needs on academic writing competence as the primary focus in higher education encourage the university institutions around the world to provide academic writing courses to support their students dealing with their tasks pertaining to this competence. However, a pilot study conducted previously in one of the universities in Palopo, a city in South Sulawesi, revealed that even though the institution has provided academic writing courses, supported by some workshops related to academic writing and some supporting facilities at campus, the students still face difficulties in completing their assignments related to academic writing, particularly in writing their theses. The present study focuses on investigating the specific needs of the students in the same institution in terms of competences required in academic writing. It is also carried out to examine whether the syllabus exists and accommodates the students’ needs or not. Questionnaire and interview were used to collect data from sixty students of sixth semester and two lecturers of the academic courses. The results reveal that the students need to learn all aspects of linguistic competence (language features, lexical phrases, academic language and vocabulary, and proper language) and some aspects in discourse competence (how to write introduction, search for appropriate literature, design research method, write coherent paragraphs, refer to sources, summarize and display data, and link sentences smoothly). Regarding the syllabus, it is found that the academic writing courses provided in the institution, where this study takes place, do not have syllabus. This condition is different from other institutions which provide syllabi for all courses. However, at the commencement of the course, the students and the lecturers have negotiated their learning goals, topics discussed, learning activities, and assessment criteria for the course. Therefore, even though the syllabus does not exist, but the elements of the syllabus are there. The negotiation between the students and the lecturers contributes to the students’ attitude toward the courses. The students are contented with the course and they feel that their needs in academic writing have been accommodated. However, some suggestions for the next academic writing courses are stated by the students. Considering the results of this study, a syllabus is then proposed which is expected to accommodate the specific needs of students in that institution.

Keywords: Students' needs, academic writing, syllabus design for instruction, case study

Procedia PDF Downloads 196
15562 Behavior of Droplets in Microfluidic System with T-Junction

Authors: A. Guellati, F-M Lounis, N. Guemras, K. Daoud

Abstract:

Micro droplet formation is considered as a growing emerging area of research due to its wide-range application in chemistry as well as biology. The mechanism of micro droplet formation using two immiscible liquids running through a T-junction has been widely studied. We believe that the flow of these two immiscible phases can be of greater important factor that could have an impact on out-flow hydrodynamic behavior, the droplets generated and the size of the droplets. In this study, the type of the capillary tubes used also represents another important factor that can have an impact on the generation of micro droplets. The tygon capillary tubing with hydrophilic inner surface doesn't allow regular out-flows due to the fact that the continuous phase doesn't adhere to the wall of the capillary inner surface. Teflon capillary tubing, presents better wettability than tygon tubing, and allows to obtain steady and regular regimes of out-flow, and the micro droplets are homogeneoussize. The size of the droplets is directly dependent on the flows of the continuous and dispersed phases. Thus, as increasing the flow of the continuous phase, to flow of the dispersed phase stationary, the size of the drops decreases. Inversely, while increasing the flow of the dispersed phase, to flow of the continuous phase stationary, the size of the droplet increases.

Keywords: microfluidic system, micro droplets generation, t-junction, fluids engineering

Procedia PDF Downloads 334
15561 Investigating the Causes of Human Error-Induced Incidents in the Maintenance Operations of Petrochemical Industry by Using Human Factors Analysis and Classification System

Authors: Omid Kalatpour, Mohammadreza Ajdari

Abstract:

This article studied the possible causes of human error-induced incidents in the petrochemical industry maintenance activities by using Human Factors Analysis and Classification System (HFACS). The purpose of the study was anticipating and identifying these causes and proposing corrective and preventive actions. Maintenance department in a petrochemical company was selected for research. A checklist of human error-induced incidents was developed based on four HFACS main levels and nineteen sub-groups. Hierarchical task analysis (HTA) technique was used to identify maintenance activities and tasks. The main causes of possible incidents were identified by checklist and recorded. Corrective and preventive actions were defined depending on priority. Analyzing the worksheets of 444 activities in four levels of HFACS showed 37.6% of the causes were at the level of unsafe actions, 27.5% at the level of unsafe supervision, 20.9% at the level of preconditions for unsafe acts and 14% of the causes were at the level of organizational effects. The HFACS sub-groups showed errors (24.36%) inadequate supervision (14.89%) and violations (13.26%) with the most frequency. According to findings of this study, increasing the training effectiveness of operators and supervision improvement respectively are the most important measures in decreasing the human error-induced incidents in petrochemical industry maintenance.

Keywords: human error, petrochemical industry, maintenance, HFACS

Procedia PDF Downloads 220
15560 Estimating Soil Erosion Using Universal Soil Loss Equation and Gis in Algash Basin

Authors: Issamaldin Mohammed, Ahmed Abdalla, Hatim Elobied

Abstract:

Soil erosion is globally known for adverse effects on social, environmental and economical aspects which directly or indirectly influence the human life. The area under study suffers from problems like water quality, river and agricultural canals bed rise due to high sediment load brought by Algash River from upstream (Eritrea high land), the current study utilized from remote sensing and Geographical Information System (GIS) to estimate the annual soil loss using Universal Soil Loss Equation (USLE). The USLE is widely used over the world which basically relies on rainfall erosivity factor (R), soil erodibility factor (K), topographic factor (LS), cover management factor (C) and support practice factor (P). The result of the study showed high soil loss in the study area, this result was illustrated in a form of map presenting the spatial distribution of soil loss amounts which classified into seven zones ranging from very slight zone (less than 2 ton/ha.year) to very severe (100-500 ton/ha.year), also the total soil loss from the whole study area was found to be 32,916,840.87 ton/ha.year. These kinds of results will help the experts of land management to give a priority for the severely affected zones to be tackled in an appropriate way.

Keywords: Geographical Information System, remote sensing, sedimentation, soil loss

Procedia PDF Downloads 279
15559 Literary Theatre and Embodied Theatre: A Practice-Based Research in Exploring the Authorship of a Performance

Authors: Rahul Bishnoi

Abstract:

Theatre, as Ann Ubersfld calls it, is a paradox. At once, it is both a literary work and a physical representation. Theatre as a text is eternal, reproducible, and identical while as a performance, theatre is momentary and never identical to the previous performances. In this dual existence of theatre, who is the author? Is the author the playwright who writes the dramatic text, or the director who orchestrates the performance, or the actor who embodies the text? From the poststructuralist lens of Barthes, the author is dead. Barthes’ argument of discrete temporality, i.e. the author is the before, and the text is the after, does not hold true for theatre. A published literary work is written, edited, printed, distributed and then gets consumed by the reader. On the other hand, theatrical production is immediate; an actor performs and the audience witnesses it instantaneously. Time, so to speak, does not separate the author, the text, and the reader anymore. The question of authorship gets further complicated in Augusto Boal’s “Theatre of the Oppressed” movement where the audience is a direct participant like the actors in the performance. In this research, through an experimental performance, the duality of theatre is explored with the authorship discourse. And the conventional definition of authorship is subjected to additional complexity by erasing the distinction between an actor and the audience. The design/methodology of the experimental performance is as follows: The audience will be asked to produce a text under an anonymous virtual alias. The text, as it is being produced, will be read and performed by the actor. The audience who are also collectively “authoring” the text, will watch this performance and write further until everyone has contributed with one input each. The cycle of writing, reading, performing, witnessing, and writing will continue until the end. The intention is to create a dynamic system of writing/reading with the embodiment of the text through the actor. The actor is giving up the power to the audience to write the spoken word, stage instruction and direction while still keeping the agency of interpreting that input and performing in the chosen manner. This rapid conversation between the actor and the audience also creates a conversion of authorship. The main conclusion of this study is a perspective on the nature of dynamic authorship of theatre containing a critical enquiry of the collaboratively produced text, an individually performed act, and a collectively witnessed event. Using practice as a methodology, this paper contests the poststructuralist notion of the author as merely a ‘scriptor’ and breaks it further by involving the audience in the authorship as well.

Keywords: practice based research, performance studies, post-humanism, Avant-garde art, theatre

Procedia PDF Downloads 90
15558 Three-Dimensional Fluid-Structure-Thermal Coupling Dynamics Simulation Model of a Gas-Filled Fluid-Resistance Damper and Experimental Verification

Authors: Wenxue Xu

Abstract:

Fluid resistance damper is an important damping element to attenuate vehicle vibration. It converts vibration energy into thermal energy dissipation through oil throttling. It is a typical fluid-solid-heat coupling problem. A complete three-dimensional flow-structure-thermal coupling dynamics simulation model of a gas-filled fluid-resistance damper was established. The flow-condition-based interpolation (FCBI) method and direct coupling calculation method, the unit's FCBI-C fluid numerical analysis method and iterative coupling calculation method are used to achieve the damper dynamic response of the piston rod under sinusoidal excitation; the air chamber inflation pressure, spring compression characteristics, constant flow passage cross-sectional area and oil parameters, etc. The system parameters, excitation frequency, and amplitude and other excitation parameters are analyzed and compared in detail for the effects of differential pressure characteristics, velocity characteristics, flow characteristics and dynamic response of valve opening, floating piston response and piston rod output force characteristics. Experiments were carried out on some simulation analysis conditions. The results show that the node-based FCBI (flow-condition-based interpolation) fluid numerical analysis method and direct coupling calculation method can better guarantee the conservation of flow field calculation, and the calculation step is larger, but the memory is also larger; if the chamber inflation pressure is too low, the damper will become cavitation. The inflation pressure will cause the speed characteristic hysteresis to increase, and the sealing requirements are too strict. The spring compression characteristics have a great influence on the damping characteristics of the damper, and reasonable damping characteristic needs to properly design the spring compression characteristics; the larger the cross-sectional area of the constant flow channel, the smaller the maximum output force, but the more stable when the valve plate is opening.

Keywords: damper, fluid-structure-thermal coupling, heat generation, heat transfer

Procedia PDF Downloads 132
15557 Risk Management for Smart Healthcare System: A Hybrid Multi-Criteria Decision-Making Framework

Authors: Abdullah Ali Salamai

Abstract:

Smart healthcare management systems (SHMS) play a vital role in medical centers. SHMS has various risks and threats that affect patient care. So, risk management is the best choice to identify and mitigate these risks. This study proposed a multi-criteria decision-making (MCDM) framework for identifying risks in SHMS and selecting the best project in SHMS to reduce risks. This study used the MCDM method to deal with conflict criteria. There are two MCDM methods: CRiteria Importance Through Intercriteria Correlation (CRITIC) and Additive Ration Assessment (ARAS). The CRITIC approach is used to compute the criteria weights, and the ARAS algorithm is used to select the appropriate projects in SHMS. The neutrosophic set (NS) was applied with MCDM methods to deal with inconsistent data in the evaluation process. The results show the Health Data Informational System project is the best. Sensitivity analysis was conducted to show the stability of the rank. The comparative study was conducted to show the effectiveness of the proposed methodology. The outcomes demonstrate the rank of projects is stable through all scenarios, and the proposed methodology is effective compared with other MCDM methods.

Keywords: risk management, portfolio management, smart healthcare, neutrosophic set, MCDM

Procedia PDF Downloads 11