Search results for: performance review discussion
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 18417

Search results for: performance review discussion

13827 Dual-Layer Microporous Layer of Gas Diffusion Layer for Proton Exchange Membrane Fuel Cells under Various RH Conditions

Authors: Grigoria Athanasaki, Veerarajan Vimala, A. M. Kannan, Louis Cindrella

Abstract:

Energy usage has been increased throughout the years, leading to severe environmental impacts. Since the majority of the energy is currently produced from fossil fuels, there is a global need for clean energy solutions. Proton Exchange Membrane Fuel Cells (PEMFCs) offer a very promising solution for transportation applications because of their solid configuration and low temperature operations, which allows them to start quickly. One of the main components of PEMFCs is the Gas Diffusion Layer (GDL), which manages water and gas transport and shows direct influence on the fuel cell performance. In this work, a novel dual-layer GDL with gradient porosity was prepared, using polyethylene glycol (PEG) as pore former, to improve the gas diffusion and water management in the system. The microporous layer (MPL) of the fabricated GDL consists of carbon powder PUREBLACK, sodium dodecyl sulfate as a surfactant, 34% wt. PTFE and the gradient porosity was created by applying one layer using 30% wt. PEG on the carbon substrate, followed by a second layer without using any pore former. The total carbon loading of the microporous layer is ~ 3 mg.cm-2. For the assembly of the catalyst layer, Nafion membrane (Ion Power, Nafion Membrane NR211) and Pt/C electrocatalyst (46.1% wt.) were used. The catalyst ink was deposited on the membrane via microspraying technique. The Pt loading is ~ 0.4 mg.cm-2, and the active area is 5 cm2. The sample was ex-situ characterized via wetting angle measurement, Scanning Electron Microscopy (SEM), and Pore Size Distribution (PSD) to evaluate its characteristics. Furthermore, for the performance evaluation in-situ characterization via Fuel Cell Testing using H2/O2 and H2/air as reactants, under 50, 60, 80, and 100% relative humidity (RH), took place. The results were compared to a single layer GDL, fabricated with the same carbon powder and loading as the dual layer GDL, and a commercially available GDL with MPL (AvCarb2120). The findings reveal high hydrophobic properties of the microporous layer of the GDL for both PUREBLACK based samples, while the commercial GDL demonstrates hydrophilic behavior. The dual layer GDL shows high and stable fuel cell performance under all the RH conditions, whereas the single layer manifests a drop in performance at high RH in both oxygen and air, caused by catalyst flooding. The commercial GDL shows very low and unstable performance, possibly because of its hydrophilic character and thinner microporous layer. In conclusion, the dual layer GDL with PEG appears to have improved gas diffusion and water management in the fuel cell system. Due to its increasing porosity from the catalyst layer to the carbon substrate, it allows easier access of the reactant gases from the flow channels to the catalyst layer, and more efficient water removal from the catalyst layer, leading to higher performance and stability.

Keywords: gas diffusion layer, microporous layer, proton exchange membrane fuel cells, relative humidity

Procedia PDF Downloads 124
13826 The Functional Magnetic Resonance Imaging and the Consumer Behaviour: Reviewing Recent Research

Authors: Mikel Alonso López

Abstract:

In the first decade of the twenty-first century, advanced imaging techniques began to be applied for neuroscience research. The Functional Magnetic Resonance Imaging (fMRI) is one of the most important and most used research techniques for the investigation of emotions, because of its ease to observe the brain areas that oxygenate when performing certain tasks. In this research, we make a review about the main research carried out on the influence of the emotions in the decision-making process that is exposed by using the fMRI.

Keywords: decision making, emotions, fMRI, consumer behaviour

Procedia PDF Downloads 479
13825 Extended Constraint Mask Based One-Bit Transform for Low-Complexity Fast Motion Estimation

Authors: Oğuzhan Urhan

Abstract:

In this paper, an improved motion estimation (ME) approach based on weighted constrained one-bit transform is proposed for block-based ME employed in video encoders. Binary ME approaches utilize low bit-depth representation of the original image frames with a Boolean exclusive-OR based hardware efficient matching criterion to decrease computational burden of the ME stage. Weighted constrained one-bit transform (WC‑1BT) based approach improves the performance of conventional C-1BT based ME employing 2-bit depth constraint mask instead of a 1-bit depth mask. In this work, the range of constraint mask is further extended to increase ME performance of WC-1BT approach. Experiments reveal that the proposed method provides better ME accuracy compared existing similar ME methods in the literature.

Keywords: fast motion estimation; low-complexity motion estimation, video coding

Procedia PDF Downloads 316
13824 Robustness of the Fuzzy Adaptive Speed Control of a Multi-Phase Asynchronous Machine

Authors: Bessaad Taieb, Benbouali Abderrahmen

Abstract:

Fuzzy controllers are a powerful tool for controlling complex processes. However, its robustness capacity remains moderately limited because it loses its property for large ranges of parametric variations. In this paper, the proposed control method is designed, based on a fuzzy adaptive controller used as a remedy for this problem. For increase the robustness of the vector control and to maintain the performance of the five-phase asynchronous machine despite the presence of disturbances (variation of rotor resistance, rotor inertia variations, sudden variations in the load etc.), by applying the method of behaviour model control (BMC). The results of simulation show that the fuzzy adaptive control provides best performance and has a more robustness as the fuzzy (FLC) and as a conventional (PI) controller.

Keywords: fuzzy adaptive control, behaviour model control, vector control, five-phase asynchronous machine

Procedia PDF Downloads 95
13823 A Study on the Effect of Design Factors of Slim Keyboard’s Tactile Feedback

Authors: Kai-Chieh Lin, Chih-Fu Wu, Hsiang Ling Hsu, Yung-Hsiang Tu, Chia-Chen Wu

Abstract:

With the rapid development of computer technology, the design of computers and keyboards moves towards a trend of slimness. The change of mobile input devices directly influences users’ behavior. Although multi-touch applications allow entering texts through a virtual keyboard, the performance, feedback, and comfortableness of the technology is inferior to traditional keyboard, and while manufacturers launch mobile touch keyboards and projection keyboards, the performance has not been satisfying. Therefore, this study discussed the design factors of slim pressure-sensitive keyboards. The factors were evaluated with an objective (accuracy and speed) and a subjective evaluation (operability, recognition, feedback, and difficulty) depending on the shape (circle, rectangle, and L-shaped), thickness (flat, 3mm, and 6mm), and force (35±10g, 60±10g, and 85±10g) of the keyboard. Moreover, MANOVA and Taguchi methods (regarding signal-to-noise ratios) were conducted to find the optimal level of each design factor. The research participants, by their typing speed (30 words/ minute), were divided in two groups. Considering the multitude of variables and levels, the experiments were implemented using the fractional factorial design. A representative model of the research samples were established for input task testing. The findings of this study showed that participants with low typing speed primarily relied on vision to recognize the keys, and those with high typing speed relied on tactile feedback that was affected by the thickness and force of the keys. In the objective and subjective evaluation, a combination of keyboard design factors that might result in higher performance and satisfaction was identified (L-shaped, 3mm, and 60±10g) as the optimal combination. The learning curve was analyzed to make a comparison with a traditional standard keyboard to investigate the influence of user experience on keyboard operation. The research results indicated the optimal combination provided input performance to inferior to a standard keyboard. The results could serve as a reference for the development of related products in industry and for applying comprehensively to touch devices and input interfaces which are interacted with people.

Keywords: input performance, mobile device, slim keyboard, tactile feedback

Procedia PDF Downloads 299
13822 The Effect of Non-Normality on CB-SEM and PLS-SEM Path Estimates

Authors: Z. Jannoo, B. W. Yap, N. Auchoybur, M. A. Lazim

Abstract:

The two common approaches to Structural Equation Modeling (SEM) are the Covariance-Based SEM (CB-SEM) and Partial Least Squares SEM (PLS-SEM). There is much debate on the performance of CB-SEM and PLS-SEM for small sample size and when distributions are non-normal. This study evaluates the performance of CB-SEM and PLS-SEM under normality and non-normality conditions via a simulation. Monte Carlo Simulation in R programming language was employed to generate data based on the theoretical model with one endogenous and four exogenous variables. Each latent variable has three indicators. For normal distributions, CB-SEM estimates were found to be inaccurate for small sample size while PLS-SEM could produce the path estimates. Meanwhile, for a larger sample size, CB-SEM estimates have lower variability compared to PLS-SEM. Under non-normality, CB-SEM path estimates were inaccurate for small sample size. However, CB-SEM estimates are more accurate than those of PLS-SEM for sample size of 50 and above. The PLS-SEM estimates are not accurate unless sample size is very large.

Keywords: CB-SEM, Monte Carlo simulation, normality conditions, non-normality, PLS-SEM

Procedia PDF Downloads 410
13821 Improvement of Heat Pipe Thermal Performance in H-VAC Systems Using CFD Modeling

Authors: H. Shokouhmand, A. Ghanami

Abstract:

Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section. In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity used in the abstract.

Keywords: heat pipe, HVAC system, grooved heat pipe, CFD simulation

Procedia PDF Downloads 425
13820 English Language Acquisition and Flipped Classroom

Authors: Yuqing Sun

Abstract:

Nowadays, English has been taught in many countries as a second language. One of the major ways to learn this language is through the class teaching. As in the field of second language acquisition, there are many factors to affect its acquisition processes, such as the target language itself, a learner’s personality, cognitive factor, language transfer, and the outward factors (teaching method, classroom, environmental factor, teaching policy, social environment and so on). Flipped Classroom as a newly developed classroom model has been widely used in language teaching classroom, which was, to some extent, accepted by teachers and students for its effect. It distinguishes itself from the traditional classroom for its focus on the learner and its great importance attaching to the personal learning process and the application of technology. The class becomes discussion-targeted, and the class order is somewhat inverted since the teaching process is carried out outside the class, while the class is only for knowledge-internalization. This paper will concentrate on the influences of the flipped classroom, as a classroom affecting factor, on the the process of English acquisition by the way of case studies (English teaching class in China), and the analysis of the mechanism of the flipped classroom itself to propose some feasible advice of promoting the the effectiveness of English acquisition.

Keywords: second language acquisition, English, flipped classroom, case

Procedia PDF Downloads 400
13819 Performance Evaluation of Reinforced Concrete Framed Structure with Steel Bracing and Supplemental Energy Dissipation

Authors: Swanand Patil, Pankaj Agarwal

Abstract:

In past few decades, seismic performance objectives have shifted from earthquake resistance to earthquake resilience of the structures, especially for the lifeline buildings. Features such as negligible post-earthquake damage and replaceable damaged components, makes energy dissipating systems a valid choice for a seismically resilient building. In this study, various energy dissipation devices are applied on an eight-storey moment resisting RC building model. The energy dissipating devices include both hysteresis-based and viscous type of devices. The seismic response of the building is obtained for different positioning and mechanical properties of the devices. The investigation is carried forward to the deficiently ductile RC frame also. The performance assessment is done on the basis of drift ratio, mode shapes and displacement response of the model structures. Nonlinear dynamic analysis shows largely improved displacement response. The damping devices improve displacement response more efficiently in the deficient ductile frames than that in the perfectly moment resisting frames. This finding is important considering the number of deficient buildings in India and the world. The placement and mechanical properties of the dampers prove to be a crucial part in modelling, analyzing and designing of the structures with supplemental energy dissipation.

Keywords: earthquake resilient structures, lifeline buildings, retrofitting of structures, supplemental energy dissipation

Procedia PDF Downloads 345
13818 Improvement of Heat Pipes Thermal Performance in H-VAC Systems Using CFD Modeling

Authors: H. Shokouhmand, A. Ghanami

Abstract:

Heat pipe is simple heat transfer device which combines the conduction and phase change phenomena to control the heat transfer without any need for external power source. At hot surface of heat pipe, the liquid phase absorbs heat and changes to vapor phase. The vapor phase flows to condenser region and with the loss of heat changes to liquid phase. Due to gravitational force the liquid phase flows to evaporator section.In HVAC systems the working fluid is chosen based on the operating temperature. The heat pipe has significant capability to reduce the humidity in HVAC systems. Each HVAC system which uses heater, humidifier or dryer is a suitable nominate for the utilization of heat pipes. Generally heat pipes have three main sections: condenser, adiabatic region and evaporator.Performance investigation and optimization of heat pipes operation in order to increase their efficiency is crucial. In present article, a parametric study is performed to improve the heat pipe performance. Therefore, the heat capacity of heat pipe with respect to geometrical and confining parameters is investigated. For the better observation of heat pipe operation in HVAC systems, a CFD simulation in Eulerian- Eulerian multiphase approach is also performed. The results show that heat pipe heat transfer capacity is higher for water as working fluid with the operating temperature of 340 K. It is also showed that the vertical orientation of heat pipe enhances it’s heat transfer capacity used in the abstract.

Keywords: heat pipe, HVAC system, grooved heat pipe, heat pipe limits

Procedia PDF Downloads 364
13817 Performance Analysis of Solar Air Heater with Fins and Perforated Twisted Tape Insert

Authors: Rajesh Kumar, Prabha Chand

Abstract:

The present paper deals with the analytical investigation on the thermal and thermo-hydraulic performance of the solar air collector fitted with fins and perforated twisted tapes (PTT) of twist ratio 2 with different axial pitch ratio. The mathematical models are presented, and the effect of mass flow rate and axial pitch ratios on the thermal and effective efficiency has been discussed. The results obtained are compared with the results of the solar air heater without fins and twisted tapes. Results conveyed that the collectors with fins and perforated twisted tape perform better but at the expense of increased pressure drop. Also, twisted tape with minimum axial pitch ratio is found to be more efficient than others.

Keywords: solar air heater, thermal efficiency, twisted tape, twist ratio

Procedia PDF Downloads 266
13816 Disabled Graduate Students’ Experiences and Vision of Change for Higher Education: A Participatory Action Research Study

Authors: Emily Simone Doffing, Danielle Kohfeldt

Abstract:

Disabled students are underrepresented in graduate-level degree enrollment and completion. There is limited research on disabled students' progression during the pandemic. Disabled graduate students (DGS) face unique interpersonal and institutional barriers, yet, limited research explores these barriers, buffering facilitators, and aids to academic persistence. This study adopts an asset-based, embodied disability approach using the critical pedagogy theoretical framework instead of the deficit research approach. The Participatory Action Research (PAR) paradigm, the critical pedagogy theoretical framework, and emancipatory disability research share the same purpose -creating a socially just world through reciprocal learning. This study is one of few, if not the first, to center solely on DGS’ lived understanding using a Participatory Action Research (PAR) epistemology. With a PAR paradigm, participants and investigators work as a research team democratically at every stage of the research process. PAR has individual and systemic outcomes. PAR lessens the researcher-participant power gap and elevates a marginalized community’s knowledge as expertise for local change. PAR and critical pedagogy work toward enriching everyone involved with empowerment, civic engagement, knowledge proliferation, socio-cultural reflection, skills development, and active meaning-making. The PAR process unveils the tensions between disability and graduate school in policy and practice during the pandemic. Likewise, institutional and ideological tensions influence the PAR process. This project is recruiting 10 DGS until September through purposive and snowball sampling. DGS will collectively practice praxis during four monthly focus groups in the fall 2023 semester. Participant researchers can attend a focus group or an interview, both with field notes. September will be our orientation and first monthly meeting. It will include access needs check-ins, ice breakers, consent form review, a group agreement, PAR introduction, research ethics discussion, research goals, and potential research topics. October and November will be available for meetings for dialogues about lived experiences during our collaborative data collection. Our sessions can be semi-structured with “framing questions,” which would be revised together. Field notes include observations that cannot be captured through audio. December will focus on local social action planning and dissemination. Finally, in January, there will be a post-study focus group for students' reflections on their experiences of PAR. Iterative analysis methods include transcribed audio, reflexivity, memos, thematic coding, analytic triangulation, and member checking. This research follows qualitative rigor and quality criteria: credibility, transferability, confirmability, and psychopolitical validity. Results include potential tension points, social action, individual outcomes, and recommendations for conducting PAR. Tension points have three components: dubious practices, contestable knowledge, and conflict. The dissemination of PAR recommendations will aid and encourage researchers to conduct future PAR projects with the disabled community. Identified stakeholders will be informed of DGS’ insider knowledge to drive social sustainability.

Keywords: participatory action research, graduate school, disability, higher education

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13815 Application of Model Free Adaptive Control in Main Steam Temperature System of Thermal Power Plant

Authors: Khaing Yadana Swe, Lillie Dewan

Abstract:

At present, the cascade PID control is widely used to control the super-heating temperature (main steam temperature). As the main steam temperature has the characteristics of large inertia, large time-delay, and time varying, etc., conventional PID control strategy can not achieve good control performance. In order to overcome the bad performance and deficiencies of main steam temperature control system, Model Free Adaptive Control (MFAC) P cascade control system is proposed in this paper. By substituting MFAC in PID of the main control loop of the main steam temperature control, it can overcome time delays, non-linearity, disturbance and time variation.

Keywords: model-free adaptive control, cascade control, adaptive control, PID

Procedia PDF Downloads 603
13814 Calibration of Residential Buildings Energy Simulations Using Real Data from an Extensive in situ Sensor Network – A Study of Energy Performance Gap

Authors: Mathieu Bourdeau, Philippe Basset, Julien Waeytens, Elyes Nefzaoui

Abstract:

As residential buildings account for a third of the overall energy consumption and greenhouse gas emissions in Europe, building energy modeling is an essential tool to reach energy efficiency goals. In the energy modeling process, calibration is a mandatory step to obtain accurate and reliable energy simulations. Nevertheless, the comparison between simulation results and the actual building energy behavior often highlights a significant performance gap. The literature discusses different origins of energy performance gaps, from building design to building operation. Then, building operation description in energy models, especially energy usages and users’ behavior, plays an important role in the reliability of simulations but is also the most accessible target for post-occupancy energy management and optimization. Therefore, the present study aims to discuss results on the calibration ofresidential building energy models using real operation data. Data are collected through a sensor network of more than 180 sensors and advanced energy meters deployed in three collective residential buildings undergoing major retrofit actions. The sensor network is implemented at building scale and in an eight-apartment sample. Data are collected for over one year and half and coverbuilding energy behavior – thermal and electricity, indoor environment, inhabitants’ comfort, occupancy, occupants behavior and energy uses, and local weather. Building energy simulations are performed using a physics-based building energy modeling software (Pleaides software), where the buildings’features are implemented according to the buildingsthermal regulation code compliance study and the retrofit project technical files. Sensitivity analyses are performed to highlight the most energy-driving building features regarding each end-use. These features are then compared with the collected post-occupancy data. Energy-driving features are progressively replaced with field data for a step-by-step calibration of the energy model. Results of this study provide an analysis of energy performance gap on an existing residential case study under deep retrofit actions. It highlights the impact of the different building features on the energy behavior and the performance gap in this context, such as temperature setpoints, indoor occupancy, the building envelopeproperties but also domestic hot water usage or heat gains from electric appliances. The benefits of inputting field data from an extensive instrumentation campaign instead of standardized scenarios are also described. Finally, the exhaustive instrumentation solution provides useful insights on the needs, advantages, and shortcomings of the implemented sensor network for its replicability on a larger scale and for different use cases.

Keywords: calibration, building energy modeling, performance gap, sensor network

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13813 A Prospective Audit to Look into Antimicrobial Prescribing in the Clinical Setting: In a Teaching Hospital in the UK

Authors: Richa Sinha, Mohammad Irfan Javed, Sanjay Singh

Abstract:

Introduction: Good antimicrobial prescribing reduces length of stay in hospital, risk of adverse events, antimicrobial resistance, and unnecessary hospital expenditure. The aim of this prospective audit was to identify any problems with antimicrobial prescribing including documentation of the relevant aspects as well as appropriateness of antibiotics use. The audit was conducted on the surgical wards in a teaching hospital in the UK. Methods: Standards included the indication, duration, choice, and prescription of antibiotic should be in line with current Regional Guidelines and should be clearly documented on the prescription chart. There should be an entry in each patients’ medical record of the diagnosis and indication for each acute antibiotic prescription issued. All prescriptions should clearly document the route, frequency and dose of antibiotic. Data collection was done for 2 weeks in the month of March 2014. A proforma including all the questions above was completed for all the patients. The results were analysed using Excel. Results: 35 patients in total were selected for the audit. 85.7% of patients had indication of antibiotic documented on the prescription chart and 68.5% of patients had indication documented in the notes. The antibiotic used was in line with hospital guidelines in 45.7% of patients, however, in a further 28.5% of patients the reason for the antibiotic prescription was microbiology approved. Therefore, in total 74.2% of patients had been prescribed appropriate antibiotics. The duration of antibiotic was documented in 68.6% of patients and the antibiotic was reviewed in 37.1% of patients. The dose, frequency and route was documented clearly in 100% of patients. Conclusion: Overall, prescribing can be improved on the surgical wards in this hospital. Only 37.1% of patients had clear documentation of a review of antibiotics. It may be that antibiotics have been reviewed but this should be clearly highlighted on the prescription chart or the notes. Failure to review antibiotics can lead to poor patient care and antimicrobial resistance and therefore it is important to address this. It is also important to address the appropriateness of antibiotics as inappropriate antibiotic prescription can lead to failure of treatment as well as antimicrobial resistance. The good points from the audit was that all patients had clear documentation of dose, route and frequency which is extremely important in the administration of antibiotics. Recommendations from this audit included to emphasize good antimicrobial prescribing at induction (twice yearly), an antimicrobial handbook for junior doctors, and re-audit in 6 months time.

Keywords: prescribing, antimicrobial, indication, duration

Procedia PDF Downloads 303
13812 Entrepreneurship, Institutional Quality, and Macroeconomic Performance: Evidence from Nigeria

Authors: Cleopatra Oluseye Ibukun

Abstract:

Following the endogenous growth theory, entrepreneurship has been considered pivotal to economic growth and development, particularly in developing countries like Nigeria. Meanwhile, efforts to reduce unemployment has yielded minimal result with over 36% of youth unemployment and a dwindling economic growth despite the country’s natural and human resource endowment. This study, therefore, investigates the effects of entrepreneurship and institutional quality on economic growth and unemployment in Nigeria over the period 1996 to 2018. The data is obtained from the National Bureau of Statistics (NBS), World Bank’s World Development Indicators (WDI), and the World Bank’s World Governance Indicators (WGI). The study period is guided by the availability of data, and the study employs both descriptive and econometric techniques of analysis (specifically, the Auto-regressive Distributed Lag Approach). This approach is preferable given that the variables are stationary at the first difference, while the bounds test suggests the existence of co-integration among the variables. By implication, an increase in entrepreneurship significantly improves economic growth, and it reduces unemployment in both the short-run and the long-run. Besides, institutional quality proxied by the control of corruption, political stability, and government effectiveness significantly mediates the interaction between entrepreneurship and macroeconomic performance. This study concludes that improved institutional quality enhances the effect of entrepreneurship on economic growth and unemployment in Nigeria, and it recommends an improvement in Nigeria’s institutional quality because it can jeopardise or augment the effect of entrepreneurship on macroeconomic performance.

Keywords: entrepreneurship, institutional quality, unemployment, gross domestic product, Nigeria

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13811 Single Carrier Frequency Domain Equalization Design to Cope with Narrow Band Jammer

Authors: So-Young Ju, Sung-Mi Jo, Eui-Rim Jeong

Abstract:

In this paper, based on the conventional single carrier frequency domain equalization (SC-FDE) structure, we propose a new SC-FDE structure to cope with narrowband jammer. In the conventional SC-FDE structure, channel estimation is performed in the time domain. When a narrowband jammer exists, time-domain channel estimation is very difficult due to high power jamming interference, which degrades receiver performance. To relieve from this problem, a new SC-FDE frame is proposed to enable channel estimation under narrow band jamming environments. In this paper, we proposed a modified SC-FDE structure that can perform channel estimation in the frequency domain and verified the performance via computer simulation.

Keywords: channel estimation, jammer, pilot, SC-FDE

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13810 Challenging Convections: Rethinking Literature Review Beyond Citations

Authors: Hassan Younis

Abstract:

Purpose: The objective of this study is to review influential papers in the sustainability and supply chain studies domain, leveraging insights from this review to develop a structured framework for academics and researchers. This framework aims to assist scholars in identifying the most impactful publications for their scholarly pursuits. Subsequently, the study will apply and trial the developed framework on selected scholarly articles within the sustainability and supply chain studies domain to evaluate its efficacy, practicality, and reliability. Design/Methodology/Approach: Utilizing the "Publish or Perish" tool, a search was conducted to locate papers incorporating "sustainability" and "supply chain" in their titles. After rigorous filtering steps, a panel of university professors identified five crucial criteria for evaluating research robustness: average yearly citation counts (25%), scholarly contribution (25%), alignment of findings with objectives (15%), methodological rigor (20%), and journal impact factor (15%). These five evaluation criteria are abbreviated as “ACMAJ" framework. Each paper then received a tiered score (1-3) for each criterion, normalized within its category, and summed using weighted averages to calculate a Final Normalized Score (FNS). This systematic approach allows for objective comparison and ranking of the research based on its impact, novelty, rigor, and publication venue. Findings: The study's findings highlight the lack of structured frameworks for assessing influential sustainability research in supply chain management, which often results in a dependence on citation counts. A complete model that incorporates five essential criteria has been suggested as a response. By conducting a methodical trial on specific academic articles in the field of sustainability and supply chain studies, the model demonstrated its effectiveness as a tool for identifying and selecting influential research papers that warrant additional attention. This work aims to fill a significant deficiency in existing techniques by providing a more comprehensive approach to identifying and ranking influential papers in the field. Practical Implications: The developed framework helps scholars identify the most influential sustainability and supply chain publications. Its validation serves the academic community by offering a credible tool and helping researchers, students, and practitioners find and choose influential papers. This approach aids field literature reviews and study suggestions. Analysis of major trends and topics deepens our grasp of this critical study area's changing terrain. Originality/Value: The framework stands as a unique contribution to academia, offering scholars an important and new tool to identify and validate influential publications. Its distinctive capacity to efficiently guide scholars, learners, and professionals in selecting noteworthy publications, coupled with the examination of key patterns and themes, adds depth to our understanding of the evolving landscape in this critical field of study.

Keywords: supply chain management, sustainability, framework, model

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13809 Architectural Design Studio (ADS) as an Operational Synthesis in Architectural Education

Authors: Francisco A. Ribeiro Da Costa

Abstract:

Who is responsible for teaching architecture; consider various ways to participate in learning, manipulating various pedagogical tools to streamline the creative process. The Architectural Design Studio (ADS) should become a holistic, systemic process responding to the complexity of our world. This essay corresponds to a deep reflection developed by the author on the teaching of architecture. The outcomes achieved are the corollary of experimentation; discussion and application of pedagogical methods that allowed consolidate the creativity applied by students. The purpose is to show the conjectures that have been considered effective in creating an intellectual environment that nurtures the subject of Architectural Design Studio (ADS), as an operational synthesis in the final stage of the degree. These assumptions, which are part of the proposed model, displaying theories and teaching methodologies that try to respect the learning process based on student learning styles Kolb, ensuring their latent specificities and formulating the structure of the ASD discipline. In addition, the assessing methods are proposed, which consider the architectural Design Studio as an operational synthesis in the teaching of architecture.

Keywords: teaching-learning, architectural design studio, architecture, education

Procedia PDF Downloads 391
13808 A Theragnostic Approach for Alzheimer’s Disease Focused on Phosphorylated Tau

Authors: Tomás Sobrino, Lara García-Varela, Marta Aramburu-Núñez, Mónica Castro, Noemí Gómez-Lado, Mariña Rodríguez-Arrizabalaga, Antía Custodia, Juan Manuel Pías-Peleteiro, José Manuel Aldrey, Daniel Romaus-Sanjurjo, Ángeles Almeida, Pablo Aguiar, Alberto Ouro

Abstract:

Introduction: Alzheimer’s disease (AD) and other tauopathies are primary causes of dementia, causing progressive cognitive deterioration that entails serious repercussions for the patients' performance of daily tasks. Currently, there is no effective approach for the early diagnosis and treatment of AD and tauopathies. This study suggests a theragnostic approach based on the importance of phosphorylated tau protein (p-Tau) in the early pathophysiological processes of AD. We have developed a novel theragnostic monoclonal antibody (mAb) to provide both diagnostic and therapeutic effects. Methods/Results: We have developed a p-Tau mAb, which was doped with deferoxamine for radiolabeling with Zirconium-89 (89Zr) for PET imaging, as well as fluorescence dies for immunofluorescence assays. The p-Tau mAb was evaluated in vitro for toxicity by MTT assay, LDH activity, propidium iodide/Annexin V assay, caspase-3, and mitochondrial membrane potential (MMP) assay in both mouse endothelial cell line (bEnd.3) and cortical primary neurons cell cultures. Importantly, non-toxic effects (up to concentrations of p-Tau mAb greater than 100 ug/mL) were detected. In vivo experiments in the tauopathy model mice (PS19) show that the 89Zr-pTau-mAb and 89Zr-Fragments-pTau-mAb are stable in circulation for up to 10 days without toxic effects. However, only less than 0.2% reached the brain, so further strategies have to be designed for crossing the Brain-Blood-Barrier (BBB). Moreover, an intraparenchymal treatment strategy was carried out. The PS19 mice were operated to implement osmotic pumps (Alzet 1004) at two different times, at 4 and 7 months, to stimulate the controlled release for one month each of the B6 antibody or the IgG1 control antibody. We demonstrated that B6-treated mice maintained their motor and memory abilities significantly compared with IgG1 treatment. In addition, we observed a significant reduction in p-Tau deposits in the brain. Conclusions /Discussion: A theragnostic pTau-mAb was developed. Moreover, we demonstrated that our p-Tau mAb recognizes very-early pathology forms of p-Tau by non-invasive techniques, such as PET. In addition, p-Tau mAb has non-toxic effects, both in vitro and in vivo. Although the p-Tau mAb is stable in circulation, only 0.2% achieve the brain. However, direct intraventricular treatment significantly reduces cognitive impairment in Alzheimer's animal models, as well as the accumulation of toxic p-Tau species.

Keywords: alzheimer's disease, theragnosis, tau, PET, immunotherapy, tauopathies

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13807 Modeling Discrimination against Gay People: Predictors of Homophobic Behavior against Gay Men among High School Students in Switzerland

Authors: Patrick Weber, Daniel Gredig

Abstract:

Background and Purpose: Research has well documented the impact of discrimination and micro-aggressions on the wellbeing of gay men and, especially, adolescents. For the prevention of homophobic behavior against gay adolescents, however, the focus has to shift on those who discriminate: For the design and tailoring of prevention and intervention, it is important to understand the factors responsible for homophobic behavior such as, for example, verbal abuse. Against this background, the present study aimed to assess homophobic – in terms of verbally abusive – behavior against gay people among high school students. Furthermore, it aimed to establish the predictors of the reported behavior by testing an explanatory model. This model posits that homophobic behavior is determined by negative attitudes and knowledge. These variables are supposed to be predicted by the acceptance of traditional gender roles, religiosity, orientation toward social dominance, contact with gay men, and by the perceived expectations of parents, friends and teachers. These social-cognitive variables in turn are assumed to be determined by students’ gender, age, immigration background, formal school level, and the discussion of gay issues in class. Method: From August to October 2016, we visited 58 high school classes in 22 public schools in a county in Switzerland, and asked the 8th and 9th year students on three formal school levels to participate in survey about gender and gay issues. For data collection, we used an anonymous self-administered questionnaire filled in during class. Data were analyzed using descriptive statistics and structural equation modelling (Generalized Least Square Estimates method). The sample included 897 students, 334 in the 8th and 563 in the 9th year, aged 12–17, 51.2% being female, 48.8% male, 50.3% with immigration background. Results: A proportion of 85.4% participants reported having made homophobic statements in the 12 month before survey, 4.7% often and very often. Analysis showed that respondents’ homophobic behavior was predicted directly by negative attitudes (β=0.20), as well as by the acceptance of traditional gender roles (β=0.06), religiosity (β=–0.07), contact with gay people (β=0.10), expectations of parents (β=–0.14) and friends (β=–0.19), gender (β=–0.22) and having a South-East-European or Western- and Middle-Asian immigration background (β=0.09). These variables were predicted, in turn, by gender, age, immigration background, formal school level, and discussion of gay issues in class (GFI=0.995, AGFI=0.979, SRMR=0.0169, CMIN/df=1.199, p>0.213, adj. R2 =0.384). Conclusion: Findings evidence a high prevalence of homophobic behavior in the responding high school students. The tested explanatory model explained 38.4% of the assessed homophobic behavior. However, data did not found full support of the model. Knowledge did not turn out to be a predictor of behavior. Except for the perceived expectation of teachers and orientation toward social dominance, the social-cognitive variables were not fully mediated by attitudes. Equally, gender and immigration background predicted homophobic behavior directly. These findings demonstrate the importance of prevention and provide also leverage points for interventions against anti-gay bias in adolescents – also in social work settings as, for example, in school social work, open youth work or foster care.

Keywords: discrimination, high school students, gay men, predictors, Switzerland

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13806 The Influence of Meteorological Properties on the Power of Night Radiation Cooling

Authors: Othmane Fahim, Naoual Belouaggadia. Charifa David, Mohamed Ezzine

Abstract:

To make better use of cooling resources, systems have been derived on the basis of the use of night radiator systems for heat pumping. Using the TRNSYS tool we determined the influence of the climatic characteristics of the two zones in Morocco on the temperature of the outer surface of a Photovoltaic Thermal Panel “PVT” made of aluminum. The proposal to improve the performance of the panel allowed us to have little heat absorption during the day and give the same performance of a panel made of aluminum at night. The variation in the granite-based panel temperature recorded a deviation from the other materials of 0.5 °C, 2.5 °C on the first day respectively in Marrakech and Casablanca, and 0.2 °C and 3.2 °C on the second night. Power varied between 110.16 and 32.01 W/m² marked in Marrakech, to be the most suitable area to practice night cooling by night radiation.

Keywords: smart buildings, energy efficiency, Morocco, radiative cooling

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13805 Prompting and Encouraging Community Hydration through Education: A Realist Review and Evaluation Exploring Hydration in a Population at Risk of Frailty

Authors: Mark Davies, Carolyn Wallace, Christina Lloydwin, Tom Powell

Abstract:

Background: Frailty is increasingly recognized as a public health problem within an aging population. It is often characterized as an accumulation of clinical symptoms with progressive decline. We contend that dehydration is potentially the missing link driving the cycle of frailty; it contributes to malnutrition and cognitive decline and is a risk factor for other conditions. Frailty may also impact on fluid intake in cognitively intact older adults, indicating the cyclical nature of dehydration contributing to increasing frailty. Aim: To examine the relationships between fluid, hydration, and frailty in older adults in order to determine what works, for whom, how, why, and in what circumstances. Methods: A Realist Synthesis was first undertaken with n=50 studies, leading to the development of a Refined Programme Theory (RPT) articulating what hydration interventions work, for whom, to what degree, in what contexts, and how & why. Within the subsequent evaluation, the RPT was further confirmed/refuted/refined following semi-structured interviews with n=8 participants (healthcare professionals and patients). The RAMESES Quality Standards were followed throughout the study. Results: The Refined Programme Theory (RPT) highlighted three factors that result in optimized hydration for frail older people, i.e., Developing an Understanding Around Hydration, Empowering Participation, and System Reconfiguration. Our RPT indicates that hydration interventions work by developing an understanding of the importance of hydration, mitigating physical & cognitive barriers, increasing the agency of the patient, using a prompting process to reinforce drinking behavior, and routinizing hydration as a dimension of overall care. Conclusion: The study indicates that a greater understanding of the importance of hydration is required for all parties. Patients also require physical and psychological support if they are to be active agents in meeting their hydration needs. At a wider ‘system’ level, organizations must work in an integrated manner introducing processes that enable continuing professional development (CPD), encourage ongoing holistic assessment, and routinize hydration support.

Keywords: frailty, dehydration, older adults, realist review, realist evaluation

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13804 Influence of Stacking Sequence and Temperature on Buckling Resistance of GFRP Infill Panel

Authors: Viriyavudh Sim, SeungHyun Kim, JungKyu Choi, WooYoung Jung

Abstract:

Glass Fiber Reinforced Polymer (GFRP) is a major evolution for energy dissipation when used as infill material for seismic retrofitting of steel frame, a basic PMC infill wall system consists of two GFRP laminates surrounding an infill of foam core. This paper presents numerical analysis in terms of buckling resistance of GFRP sandwich infill panels system under the influence of environment temperature and stacking sequence of laminate skin. Mode of failure under in-plane compression is studied by means of numerical analysis with ABAQUS platform. Parameters considered in this study are contact length between infill and frame, laminate stacking sequence of GFRP skin and variation of mechanical properties due to increment of temperature. The analysis is done with four cases of simple stacking sequence over a range of temperature. The result showed that both the effect of temperature and stacking sequence alter the performance of entire panel system. The rises of temperature resulted in the decrements of the panel’s strength. This is due to the polymeric nature of this material. Additionally, the contact length also displays the effect on the performance of infill panel. Furthermore, the laminate stiffness can be modified by orientation of laminate, which can increase the infill panel strength. Hence, optimal performance of the entire panel system can be obtained by comparing different cases of stacking sequence.

Keywords: buckling resistance, GFRP infill panel, stacking sequence, temperature dependent

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13803 Forced Immigration to Turkey: The Socio-Spatial Impacts of Syrian Immigrants on Turkish Cities

Authors: Tolga Levent

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Throughout the past few decades, forced immigration has been a significant problem for many developing countries. Turkey is one of those countries, which has experienced lots of forced immigration waves in the Republican era. However, the ongoing forced immigration wave of Syrians started with Syrian Civil War in 2011, is strikingly influential due to its intensity. In six years, approximately 3,4 million Syrians have entered to Turkey and presented high-level spatial concentrations in certain cities proximate to the Syrian border. These concentrations make Syrians and their problems relatively visible, especially in those cities. The problems of Syrians in Turkish cities could be associated with all dimensions of daily lives. Within economical dimension, high rates of Syrian unemployment push them to informal jobs offering very low wages. The financial aids they continuously demand from public authorities trigger anti-Syrian behaviors of local communities. Moreover, their relatively limited social adaptation capacities increase integration problems within social dimension day by day. Even, there are problems related to public health dimension such as the reappearance of certain child's illnesses due to the insufficiency of vaccination of Syrian children. These problems are significant but relatively easy to be prevented by using different types of management strategies and structural policies. However, there are other types of problems -urban problems- emerging with socio-spatial impacts of Syrians on Turkish cities in a very short period of time. There are relatively limited amount of studies about these impacts since they are difficult to be comprehended. The aim of the study, in this respect, is to understand these rapidly-emerging impacts and urban problems resulted from this massive immigration influx and to discuss new qualities of urban planning facing them. In the first part, there is a brief historical consideration of forced immigration waves in Turkey. These waves are important to make comparison with the ongoing immigration wave and to understand its significance. The second part is about quantitative and qualitative analyses of the spatial existence of Syrian immigrants in the city of Mersin, as an example of cities where Syrians are highly concentrated. By using official data from public authorities, quantitative statistical analyses are made to detect spatial concentrations of Syrians at neighborhood level. As methods of qualitative research, observations and in-depth interviews are used to define socio-spatial impacts of Syrians. The main results show that there emerges 'cities in cities' though sharp socio-spatial segregations which change density surfaces; produce unforeseen land-use patterns; result in inadequacies of public services and create degradations/deteriorations of urban environments occupied by Syrians. All these problems are significant; however, Turkish planning system does not have a capacity to cope with them. In the final part, there is a discussion about new qualities of urban planning facing these impacts and urban problems. The main point of discussion is the possibility of resilient urban planning under the conditions of uncertainty and unpredictability fostered by immigration crisis. Such a resilient planning approach might provide an option for countries aiming to cope with negative socio-spatial impacts of massive immigration influxes.

Keywords: cities, forced immigration, Syrians, urban planning

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13802 The Influence of Family of Origin on Children: A Comprehensive Model and Implications for Positive Psychology and Psychotherapy

Authors: Meichen He, Xuan Yang

Abstract:

Background: In the field of psychotherapy, the role of the family of origin is of utmost importance. Over the past few decades, both individual-oriented and family-oriented approaches to child therapy have shown moderate success in reducing children's psychological and behavioral issues. Objective: However, in exploring how the family of origin influences individuals, it has been noted that there is a lack of comprehensive measurement indicators and an absence of an exact model to assess the impact of the family of origin on individual development. Therefore, this study aims to develop a model based on a literature review regarding the influence of the family of origin on children. Specifically, it will examine the effects of factors such as education level, economic status, maternal age, family integration, family violence, marital conflict, parental substance abuse, and alcohol consumption on children's self-confidence and life satisfaction. Through this research, we aim to further investigate the impact of the family of origin on children and provide directions for future research in positive psychology and psychotherapy. Methods: This study will employ a literature review methodology to gather and analyze relevant research articles on the influence of the family of origin on children. Subsequently, we will conduct quantitative analyses to establish a comprehensive model explaining how family of origin factors affect children's psychological and behavioral outcomes. Findings: the research has revealed that family of origin factors, including education level, economic status, maternal age, family integration, family violence, marital conflict, parental drug and alcohol consumption, have an impact on children's self-confidence and life satisfaction. These factors can affect children's psychological well-being and happiness through various pathways. Implications: The results of this study will contribute to a better understanding of the influence of the family of origin on children and provide valuable directions for future research in positive psychology and psychotherapy. This research will enhance awareness of children's psychological well-being and lay the foundation for improving psychotherapeutic methods.

Keywords: family of origion, positive psychology, developmental psychology, family education, social psychology, educational psychology

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13801 The Impact of Bitcoin on Stock Market Performance

Authors: Oliver Takawira, Thembi Hope

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This study will analyse the relationship between Bitcoin price movements and the Johannesburg stock exchange (JSE). The aim is to determine whether Bitcoin price movements affect the stock market performance. As crypto currencies continue to gain prominence as a safe asset during periods of economic distress, this raises the question of whether Bitcoin’s prosperity could affect investment in the stock market. To identify the existence of a short run and long run linear relationship, the study will apply the Autoregressive Distributed Lag Model (ARDL) bounds test and a Vector Error Correction Model (VECM) after testing the data for unit roots and cointegration using the Augmented Dicker Fuller (ADF) and Phillips-Perron (PP). The Non-Linear Auto Regressive Distributed Lag (NARDL) will then be used to check if there is a non-linear relationship between bitcoin prices and stock market prices.

Keywords: bitcoin, stock market, interest rates, ARDL

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13800 Polymer Modification of Fine Grained Concretes Used in Textile Reinforced Cementitious Composites

Authors: Esma Gizem Daskiran, Mehmet Mustafa Daskiran, Mustafa Gencoglu

Abstract:

Textile reinforced cementitious composite (TRCC) is a development of a composite material where textile and fine-grained concrete (matrix) materials are used in combination. These matrices offer high performance properties in many aspects. To achieve high performance, polymer modified fine-grained concretes were used as matrix material which have high flexural strength. In this study, ten latex polymers and ten powder polymers were added to fine-grained concrete mixtures. These latex and powder polymers were added to the mixtures at different rates related to binder weight. Mechanical properties such as compressive and flexural strength were studied. Results showed that latex polymer and redispersible polymer modified fine-grained concretes showed different mechanical performance. A wide range of both latex and redispersible powder polymers were studied. As the addition rate increased compressive strength decreased for all mixtures. Flexural strength increased as the addition rate increased but significant enhancement was not observed through all mixtures.

Keywords: textile reinforced composite, cement, fine grained concrete, latex, redispersible powder

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13799 Performance Analysis of 180 nm Low Voltage Low Power CMOS OTA for High Frequency Application

Authors: D. J. Dahigaonkar, D. G. Wakde

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The performance analysis of low voltage low power CMOS OTA is presented in this paper. The differential input single output OTA is simulated in 180nm CMOS process technology. The simulation results indicate high bandwidth of the order of 7.04GHz with 0.766mW power consumption and transconductance of -71.20dB. The total harmonic distortion for 100mV input at a frequency of 1MHz is found to be 2.3603%. In addition to this, to establish comparative analysis of designed OTA and analyze effect of technology scaling, the differential input single output OTA is further simulated using 350nm CMOS process technology and the comparative analysis is presented in this paper.

Keywords: Operational Transconductance Amplifier, Total Harmonic Distortions, low voltage/low power, power dissipation

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13798 Sustainable Management of Gastronomy Experiences as a Mechanism to Promote the Local Economy

Authors: Marianys Fernandez

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Gastronomic experiences generate a positive impact on the dynamization of the economy when they are managed in a sustainable manner, given that they value the identity of the destination, strengthen cooperation between stakeholders in the sector, contribute to the preservation of gastronomic heritage, and encourage the implementation of competitive and sustainable public policies. Having as its main aim the analysis of sustainable management of gastronomic experiences, this study analyses different elements associated with the promotion of the local economy. For this purpose, a systematic literature review was carried out to identify, select, synthesise, and evaluate the studies that respond to the research objectives in order to select more reliable articles for research and reduce the potential for bias within the review of literature. To obtain reliable, updated and relevant sources for scientific research, the Web of Science and Scopus databases were used, taking into account the following key words: (1) experiential tourism, (2) gastronomy experience, (3) sustainable destination management, (4) sustainable gastronomy, (5) sustainable economy, in which we obtained a final list of 76 articles. The analysis of the literature allowed us to identify the most pertinent elements referring to the objective of the study: (a) need for competitive policies in the gastronomic sector to promote sustainable local economic development, (b) incentive for cooperation between stakeholders in the gastronomic sector, to guarantee the competitiveness of the destination, (c) propose sustainable standards in the gastronomic tourism sector that link the local economy. Gastronomic experiences constitute a dynamic element of the local economy and promote sustainable tourism. We can highlight that sustainability is a mechanism for the preservation of regional identity in the gastronomic sector through the valuation of the attributes of gastronomy, promotion of the local economy, strengthening of strategic alliances between the stakeholders of the gastronomic sector and its relevant contribution to the competitiveness of the destination. The theoretical implications of the study are focused on suggesting planning, management, and policy criteria to promote the sustainable management of gastronomic experiences in order to promote the local economy. In the practical context, research integrates different approaches, tools, and methods to encourage the active participation of local actors in the promotion of the local economy through the sustainable management of gastronomic tourism.

Keywords: experiential tourism, gastronomy experience, sustainable destination management, sustainable economy, sustainable gastronomy

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