Search results for: long range order
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 23594

Search results for: long range order

18254 Study on the Role of Positive Emotions in Developmental Psychology

Authors: Hee Soo Kim, Ha Young Kyung

Abstract:

This paper examines the role of positive emotions in human psychology. By understanding Fredrickson and Lyubomirsky et al.’s on positive emotions, one can better understand people’s intuitive understanding, mental health and well-being. Fredrickson asserts that positive emotions create positive affects and personal resources, and Lyubomirsky et al. relate such positive resources to the creation of happiness and personal development. This paper finds that positive emotions play a significant role in the learning process, and they are instrumental in creating a long-lasting repertoire of personal resources and play an essential role in the development of the intuitive understanding of life variables, resilience in coping with life challenges, and ability to build more successful lives.

Keywords: Positive emotions, positive affects, personal resources, negative emotions, development

Procedia PDF Downloads 302
18253 Use of Progressive Feedback for Improving Team Skills and Fair Marking of Group Tasks

Authors: Shaleeza Sohail

Abstract:

Self, and peer evaluations are some of the main components in almost all group assignments and projects in higher education institutes. These evaluations provide students an opportunity to better understand the learning outcomes of the assignment and/or project. A number of online systems have been developed for this purpose that provides automated assessment and feedback of students’ contribution in a group environment based on self and peer evaluations. All these systems lack a progressive aspect of these assessments and feedbacks which is the most crucial factor for ongoing improvement and life-long learning. In addition, a number of assignments and projects are designed in a manner that smaller or initial assessment components lead to a final assignment or project. In such cases, the evaluation and feedback may provide students an insight into their performance as a group member for a particular component after the submission. Ideally, it should also create an opportunity to improve for next assessment component as well. Self and Peer Progressive Assessment and Feedback System encourages students to perform better in the next assessment by providing a comparative analysis of the individual’s contribution score on an ongoing basis. Hence, the student sees the change in their own contribution scores during the complete project based on smaller assessment components. Self-Assessment Factor is calculated as an indicator of how close the self-perception of the student’s own contribution is to the perceived contribution of that student by other members of the group. Peer-Assessment Factor is calculated to compare the perception of one student’s contribution as compared to the average value of the group. Our system also provides a Group Coherence Factor which shows collectively how group members contribute to the final submission. This feedback is provided for students and teachers to visualize the consistency of members’ contribution perceived by its group members. Teachers can use these factors to judge the individual contributions of the group members in the combined tasks and allocate marks/grades accordingly. This factor is shown to students for all groups undertaking same assessment, so the group members can comparatively analyze the efficiency of their group as compared to other groups. Our System provides flexibility to the instructors for generating their own customized criteria for self and peer evaluations based on the requirements of the assignment. Students evaluate their own and other group members’ contributions on the scale from significantly higher to significantly lower. The preliminary testing of the prototype system is done with a set of predefined cases to explicitly show the relation of system feedback factors to the case studies. The results show that such progressive feedback to students can be used to motivate self-improvement and enhanced team skills. The comparative group coherence can promote a better understanding of the group dynamics in order to improve team unity and fair division of team tasks.

Keywords: effective group work, improvement of team skills, progressive feedback, self and peer assessment system

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18252 Transient Current Investigations in Liquid Crystalline Polyurethane

Authors: Jitendra Kumar Quamara, Sohan Lal, Pushkar Raj

Abstract:

Electrical conduction behavior of liquid crystalline polyurethane (LCPU) has been investigated under transient conditions in the operating temperature range 50-220°C at various electric fields of 4.35-43.45 kV/cm. The transient currents show the hyperbolic decay character and the decay exponent ∆t (one tenth decay time) dependent on field as well as on temperature. The increase in I0/Is values (where I0 represents the current observed immediately after applying the voltage and Is represents the steady state current) and the variation of mobility at high operating temperatures shows the appearance of mesophase. The origin of transient currents has been attributed to the dipolar nature of carbonyl (C=O) groups in the main chain of LCPU and the trapping charge carriers.

Keywords: electrical conduction, transient current, liquid crystalline polymers, mesophase

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18251 Predicting Survival in Cancer: How Cox Regression Model Compares to Artifial Neural Networks?

Authors: Dalia Rimawi, Walid Salameh, Amal Al-Omari, Hadeel AbdelKhaleq

Abstract:

Predication of Survival time of patients with cancer, is a core factor that influences oncologist decisions in different aspects; such as offered treatment plans, patients’ quality of life and medications development. For a long time proportional hazards Cox regression (ph. Cox) was and still the most well-known statistical method to predict survival outcome. But due to the revolution of data sciences; new predication models were employed and proved to be more flexible and provided higher accuracy in that type of studies. Artificial neural network is one of those models that is suitable to handle time to event predication. In this study we aim to compare ph Cox regression with artificial neural network method according to data handling and Accuracy of each model.

Keywords: Cox regression, neural networks, survival, cancer.

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18250 Kinetic Study of the Esterification of Unsaturated Fatty Acids from Salmon Oil (Salmosalar L.)

Authors: André Luis Lima de Oliveira, Vera Lúcia Viana do Nascimento, Victória Maura Silva Bermudez, Mauricio Nunes Kleinberg, João Carlos da Costa Assunção, José Osvaldo Beserra Carioca

Abstract:

The objective of this study was to synthesize a triglyceride with high content of unsaturated fatty acids from salmon oil (Salmo salar L.) by esterification with glycerol catalyzed dealuminized zeolite. A kinetic study was conducted to determine the reaction order and the activation energy. A statistical study was conducted to determine optimal reaction conditions. Initially, the crude oil was refined salmon physically and chemically. The crude oil was hydrolyzed and unsaturated free fatty acids were separated by urea complexation method. An experimental project to verify the parameters (temperature, glycerin and catalyst) with the greatest impact on the reaction was developed. In experiments aliquots were taken at predetermined times to measure the amount of free fatty acids. Pareto, surface, contour and hub graphs were used to determine the factors that maximized the reaction. According to the graphs the best reaction conditions were: temperature 80 ° C, the proportion glycerine/oil 5: 1 and 1% of catalyst. The kinetic data showed that the system was compatible with a second-order reaction. After analyzing the rate constant versus temperature charts a value of 85.31 kJ/mol was obtained for the reaction activation energy.

Keywords: esterification, kinect, oil, salmon

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18249 Recurrent Anterior Gleno-Humeral Instability Management by Modified Latarjet Procedure

Authors: Tarek Aly

Abstract:

The shoulder is the most mobile joint whose stability requires the interaction of both dynamic and static stabilizers. Its wide range of movement predisposes to a high susceptibility to dislocation, accounting for nearly 50% of all dislocations. This trauma typically results in ligament injury (e.g., labral tear, capsular strain) or bony fracture (e.g., loss of glenoid or humeral head bone), which frequently causes recurrent instability. Patients with significant glenoid defects may require Latarjet procedure, which involves transferring the coracoid to the antero-inferior glenoid rim. In spite of outstanding results, 15 to 30% of cases suffer complications. In this article, we discuss the diagnosis of recurrent shoulder instability, the surgical technique and various complications of Latarjet procedure.

Keywords: recurrent, anterior gleno-humeral instability, latarjet, unstable shoulder

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18248 Design and Modelling of Ge/GaAs Hetero-structure Bipolar Transistor

Authors: Samson Mil'shtein, Dhawal N. Asthana

Abstract:

The presented heterostructure n-p-n bipolar transistor is comprised of Ge/GaAs heterojunctions consisting of 0.15µm thick emitter and 0.65µm collector junctions. High diffusivity of carriers in GaAs base was major motivation of current design. We avoided grading of the base which is common in heterojunction bipolar transistors, in order to keep the electron diffusivity as high as possible. The electrons injected into the 0.25µm thick p-type GaAs base with not very high doping (1017cm-3). The designed HBT enables cut off frequency on the order of 150GHz. The Ge/GaAs heterojunctions presented in our paper have proved to work better than comparable HBTs having GaAs bases and emitter/collector junctions made, for example, of AlGaAs/GaAs or other III-V compound semiconductors. The difference in lattice constants between Ge and GaAs is less than 2%. Therefore, there is no need of transition layers between Ge emitter and GaAs base. Significant difference in energy gap of these two materials presents new scope for improving performance of the emitter. With the complete structure being modelled and simulated using TCAD SILVACO, the collector/ emitter offset voltage of the device has been limited to a reasonable value of 63 millivolts by the dint of low energy band gap value associated with Ge emitter. The efficiency of the emitter in our HBT is 86%. Use of Germanium in the emitter and collector regions presents new opportunities for integration of this vertical device structure into silicon substrate.

Keywords: Germanium, Gallium Arsenide, heterojunction bipolar transistor, high cut-off frequency

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18247 Coupled Flexural-Lateral-Torsional of Shear Deformable Thin-Walled Beams with Asymmetric Cross-Section–Closed Form Exact Solution

Authors: Mohammed Ali Hjaji, Magdi Mohareb

Abstract:

This paper develops the exact solutions for coupled flexural-lateral-torsional static response of thin-walled asymmetric open members subjected to general loading. Using the principle of stationary total potential energy, the governing differential equations of equilibrium are formulated as well as the associated boundary conditions. The formulation is based on a generalized Timoshenko-Vlasov beam theory and accounts for the effects of shear deformation due to bending and warping, and captures the effects of flexural–torsional coupling due to cross-section asymmetry. Closed-form solutions are developed for cantilever and simply supported beams under various forces. In order to demonstrate the validity and the accuracy of this solution, numerical examples are presented and compared with well-established ABAQUS finite element solutions and other numerical results available in the literature. In addition, the results are compared against non-shear deformable beam theories in order to demonstrate the shear deformation effects.

Keywords: asymmetric cross-section, flexural-lateral-torsional response, Vlasov-Timoshenko beam theory, closed form solution

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18246 Pre-Analytical Laboratory Performance Evaluation Utilizing Quality Indicators between Private and Government-Owned Hospitals Affiliated to University of Santo Tomas

Authors: A. J. Francisco, K. C. Gallosa, R. J. Gasacao, J. R. Ros, B. J. Viado

Abstract:

The study focuses on the use of quality indicators (QI)s based on the standards made by the (IFCC), that could effectively identify and minimize errors occurring throughout the total testing process (TTP), in order to improve patient safety. The study was conducted through a survey questionnaire that was given to a random sample of 19 respondents (eight privately-owned and eleven government-owned hospitals), mainly CMTs, MTs, and Supervisors from UST-affiliated hospitals. The pre-analytical laboratory errors, which include misidentification errors, transcription errors, sample collection errors and sample handling and transportation errors, were considered as variables according to the IFCC WG-LEPS. Data gathered were analyzed using the Mann-Whitney U test, Percentile, Linear Regression, Percentage, and Frequency. The laboratory performance of both hospitals is High level. There is no significant difference between the laboratory performance between the two stated variables. Moreover, among the four QIs, sample handling and transportation errors contributed most to the difference between the two variables. Outcomes indicate satisfactory performance between both variables. However, in order to ensure high-quality and efficient laboratory operation, constant vigilance and improvements in pre-analytical QI are still needed. Expanding the coverage of the study, the inclusion of other phases, utilization of parametric tests are recommended.

Keywords: pre-analytical phase, quality indicators, laboratory performance, pre-analytical error

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18245 A Fault Analysis Cracked-Rotor-to-Stator Rub and Unbalance by Vibration Analysis Technique

Authors: B. X. Tchomeni, A. A. Alugongo, L. M. Masu

Abstract:

An analytical 4-DOF nonlinear model of a de Laval rotor-stator system based on Energy Principles has been used theoretically and experimentally to investigate fault symptoms in a rotating system. The faults, namely rotor-stator-rub, crack and unbalance are modelled as excitations on the rotor shaft. Mayes steering function is used to simulate the breathing behaviour of the crack. The fault analysis technique is based on waveform signal, orbits and Fast Fourier Transform (FFT) derived from simulated and real measured signals. Simulated and experimental results manifest considerable mutual resemblance of elliptic-shaped orbits and FFT for a same range of test data.

Keywords: a breathing crack, fault, FFT, nonlinear, orbit, rotor-stator rub, vibration analysis

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18244 Urban Park Characteristics Defining Avian Community Structure

Authors: Deepti Kumari, Upamanyu Hore

Abstract:

Cities are an example of a human-modified environment with few fragments of urban green spaces, which are widely considered for urban biodiversity. The study aims to address the avifaunal diversity in urban parks based on the park size and their urbanization intensity. Also, understanding the key factors affecting species composition and structure as birds are a good indicator of a healthy ecosystem, and they are sensitive to changes in the environment. A 50 m-long line-transect method is used to survey birds in 39 urban parks in Delhi, India. Habitat variables, including vegetation (percentage of non-native trees, percentage of native trees, top canopy cover, sub-canopy cover, diameter at breast height, ground vegetation cover, shrub height) were measured using the quadrat method along the transect, and disturbance variables (distance from water, distance from road, distance from settlement, park area, visitor rate, and urbanization intensity) were measured using ArcGIS and google earth. We analyzed species data for diversity and richness. We explored the relation of species diversity and richness to habitat variables using the multi-model inference approach. Diversity and richness are found significant in different park sizes and their urbanization intensity. Medium size park supports more diversity, whereas large size park has more richness. However, diversity and richness both declined with increasing urbanization intensity. The result of CCA revealed that species composition in urban parks was positively associated with tree diameter at breast height and distance from the settlement. On the model selection approach, disturbance variables, especially distance from road, urbanization intensity, and visitors are the best predictors for the species richness of birds in urban parks. In comparison, multiple regression analysis between habitat variables and bird diversity suggested that native tree species in the park may explain the diversity pattern of birds in urban parks. Feeding guilds such as insectivores, omnivores, carnivores, granivores, and frugivores showed a significant relation with vegetation variables, while carnivores and scavenger bird species mainly responded with disturbance variables. The study highlights the importance of park size in urban areas and their urbanization intensity. It also indicates that distance from the settlement, distance from the road, urbanization intensity, visitors, diameter at breast height, and native tree species can be important determining factors for bird richness and diversity in urban parks. The study also concludes that the response of feeding guilds to vegetation and disturbance in urban parks varies. Therefore, we recommend that park size and surrounding urban matrix should be considered in order to increase bird diversity and richness in urban areas for designing and planning.

Keywords: diversity, feeding guild, urban park, urbanization intensity

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18243 The Impact of Artificial Intelligence on Human Developments Obligations and Theories

Authors: Seham Elia Moussa Shenouda

Abstract:

The relationship between development and human rights has long been the subject of academic debate. To understand the dynamics between these two concepts, various principles are adopted, from the right to development to development-based human rights. Despite the initiatives taken, the relationship between development and human rights remains unclear. However, the overlap between these two views and the idea that efforts should be made in the field of human rights have increased in recent years. It is then evaluated whether the right to sustainable development is acceptable or not. The article concludes that the principles of sustainable development are directly or indirectly recognized in various human rights instruments, which is a good answer to the question posed above. This book therefore cites regional and international human rights agreements such as , as well as the jurisprudence and interpretative guidelines of human rights institutions, to prove this hypothesis.

Keywords: sustainable development, human rights, the right to development, the human rights-based approach to development, environmental rights, economic development, social sustainability human rights protection, human rights violations, workers’ rights, justice, security

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18242 Stochastic Simulation of Random Numbers Using Linear Congruential Method

Authors: Melvin Ballera, Aldrich Olivar, Mary Soriano

Abstract:

Digital computers nowadays must be able to have a utility that is capable of generating random numbers. Usually, computer-generated random numbers are not random given predefined values such as starting point and end points, making the sequence almost predictable. There are many applications of random numbers such business simulation, manufacturing, services domain, entertainment sector and other equally areas making worthwhile to design a unique method and to allow unpredictable random numbers. Applying stochastic simulation using linear congruential algorithm, it shows that as it increases the numbers of the seed and range the number randomly produced or selected by the computer becomes unique. If this implemented in an environment where random numbers are very much needed, the reliability of the random number is guaranteed.

Keywords: stochastic simulation, random numbers, linear congruential algorithm, pseudorandomness

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18241 The Effects of Architectural Anatomy on Improving the Quality of Place Identity: Case Study of Shiraz Opera Hall

Authors: Hamid Reza Zeraatpisheh, Shamsoddin Hashemi, Farshad Negintaji

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This study has examined the effects of the architectural anatomy of opera hall on improving the quality of place identity. By measuring the effects of place identity on the inner aspects of human which are influenced by the physical and social environments it has investigated the results of a balance between internal and external environment. To assess the anatomical effects of urban landscape, two components of subjective landscape including perception and diversity and the component of objective landscape including form and order have been measured. The current survey is descriptive and the statistical population has been Shiraz which is a city in Iran. To analyze the data the SPSS software has been used. The results have been investigated in two levels of descriptive and inferential statistics. In the inferential statistics, Pearson correlation coefficient has been used to evaluate the research hypotheses. The results of this study indicate that between the dimensions of landscape, the component of the subjective landscape has the highest impact on the place identity and in the second place, an objective landscape has the impact on the place identity. Anatomical effects have an important role on improving the quality of place identity of Shiraz citizens and in order to enhance the place identity in the urban landscape it is also required that they will be inspired and operated.

Keywords: architectural anatomy, identity, place identity, urban landscape, perception

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18240 Farm Bank: The Leveraging of Capital on a Limpopo Citrus Farm

Authors: Gabriella Vermeulen

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This paper applies a Bourdieusian lens to a Limpopo Citrus farm referred to as Malapeng in order to understand how conflict and authority are reproduced in Malapeng in the larger context of the South African agricultural industry. The South African citrus industry is an export industry, with South Africa being the second largest exporter of citrus in the world. Agriculture in South Africa has undergone extensive liberalisation since 1994, and many historical patterns, such as the racial divide in agriculture and the exploitation of black workers, are still continuously reproduced on farms in South Africa. This chapter looks at the institution of the ‘farm bank’ on Malapeng, which provides loans to workers whose livelihood strategies have been otherwise limited both by the larger agricultural context they are a part of and by the owner of Malapeng. By discussing the role of farm banks in a conflict between two permanent workers, the chapter illustrates how various oppositional discourses are strategically emphasised or de-emphasised at different times by the actors on Malapeng depending on their immediate goals. Farm bank proves to be a nexus of various discourses on Malapeng as the actors on Malapeng all construct farm bank in different (and often contradictory) terms in order to explain their influence and responsibility on Malapeng. The findings of the paper are based on data collected during fieldwork for an MA dissertation and are based on observation and semi-structured interviews conducted in 2021.

Keywords: agriculture, South Africa, capital, labour

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18239 Multi-Source Data Fusion for Urban Comprehensive Management

Authors: Bolin Hua

Abstract:

In city governance, various data are involved, including city component data, demographic data, housing data and all kinds of business data. These data reflects different aspects of people, events and activities. Data generated from various systems are different in form and data source are different because they may come from different sectors. In order to reflect one or several facets of an event or rule, data from multiple sources need fusion together. Data from different sources using different ways of collection raised several issues which need to be resolved. Problem of data fusion include data update and synchronization, data exchange and sharing, file parsing and entry, duplicate data and its comparison, resource catalogue construction. Governments adopt statistical analysis, time series analysis, extrapolation, monitoring analysis, value mining, scenario prediction in order to achieve pattern discovery, law verification, root cause analysis and public opinion monitoring. The result of Multi-source data fusion is to form a uniform central database, which includes people data, location data, object data, and institution data, business data and space data. We need to use meta data to be referred to and read when application needs to access, manipulate and display the data. A uniform meta data management ensures effectiveness and consistency of data in the process of data exchange, data modeling, data cleansing, data loading, data storing, data analysis, data search and data delivery.

Keywords: multi-source data fusion, urban comprehensive management, information fusion, government data

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18238 Viability of Permaculture Principles to Sustainable Agriculture Enterprises in Malta

Authors: Byron Baron

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Malta is a Mediterranean archipelago presenting a combination of environmental conditions which are less suitable for agriculture. This has resulted in a heavy dependence on agricultural chemicals, as well as over-extraction of groundwater, compounded by concomitant destruction of natural habitat surrounding the land areas used for agriculture. Such prolonged intensive land use has resulted in even greater degradation of Maltese soils. This study was thus designed with the goal of assessing the viability of implementing a sustainable agricultural system based on permaculture practices compared to the traditional local practices applied for intensive farming. The permaculture model was implemented over a period of two years for a number of locally-grown staple crops. The tangible targets included improved soil health, reduced water consumption, increased reliance on renewable energy, increased wild plant and insect diversity, and sustained crop yield. To achieve this in the permaculture test area, numerous practices were introduced. In line with permaculture principles land, tillage was reduced, only natural fertilisers were used, no herbicides or pesticides were used, irrigation was linked to a desalination system with sensors for monitoring soil parameters, mulching was practiced, and a photovoltaic system was installed. Furthermore, areas for wild plants were increased and controlled only by trimming, not mowing. A variety of environmental parameters were measured at regular intervals as well as crop yield (in kilos of produce) in order to quantify if any improvements in crop output and environmental conditions were obtained. The results obtained show a very slight improvement in overall soil health due to the brevity of the test period. Water consumption was reduced by over 50% with no apparent losses or ill effects on the crops. Renewable energy was sufficient to provide all electric power on-site, so apart from the initial investment costs, there were no limitations. Moreover, surrounding the commercial crops with borders of wild plants whilst only taking up less than 15% of the total land area assisted pollination, increased animal visitors, and did not give rise to any pest infestations. The conclusion from this study was that whilst results are promising, more detailed and long-term studies are required to understand the full extent of the implications brought about by such a transition, which hints towards the untapped potential of investing in the available resources on the island with the goal of improving the balance between economic prosperity and ecological sustainability.

Keywords: agronomic measures, ecological amplification, sustainability, permaculture

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18237 Environment Patterns and Mental Health of Older Adults in Long-Term Care Facilities: The Role of Activity Profiles

Authors: Shiau-Fang Chao, Yu-Chih Chen

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Owing to physical limitations and restrained lifestyle, older long-term care (LTC) residents are more likely to be affected by their environment than their community-dwelling counterparts. They also participate fewer activities and experience worse mental health than healthy older adults. This study adopts the ICF model to determine the extent to which the clustered patterns of LTC environment and activity participation are associated with older residents’ mental health. Method: Data were collected from a stratified equal probability sample of 634 older residents in 155 LTC institutions in Taiwan. Latent profile analysis (LPA) and latent class analysis (LCA) were conducted to explore the profiles for environment and activity participation. Multilevel modeling was performed to elucidate the relationships among environment profiles, activity profiles, and mental health. Results: LPA identified three mutually exclusive environment profiles (Low-, Moderate-, and High-Support Environment) based on the physical, social, and attitudinal environmental domains, consolidated from 12 environmental measures. LCA constructed two distinct activity profiles (Low- and High-Activity Participation) across seven activity domains (outdoor, volunteer-led leisure, spiritual, household chores, interpersonal exchange, social, and sedentary activity) that were factored from 20 activities. Compared to the Low-Support Environment class, older adults in the Moderate- and High-Support Environment classes had better mental health. Older residents in the Moderate- and High-Support Environment classes were more likely to be in the “High Activity” class, which in turn, exhibited better mental health. Conclusion: This study advances the current knowledge through rigorous methods and study design. The study findings lead to several conclusions. First, this study supports the use of ICF framework to institutionalized older individuals with functional limitations and demonstrates that both measures of environment and activity participation can be refined from multiple indicators. Second, environmental measures that encompass the physical, social, and attitudinal domains would provide a more comprehensive assessment on the place where an older individual embeds. Third, simply counting activities in which an older individual participates or considering a certain type of activity may not capture his or her way of life. Practitioners should not only focus on group or leisure activities within the institutions; rather, more efforts should be made to consider residents’ preferences for everyday life and support their remaining ability by encouraging continuous participation in activities they still willing and capable to perform. Fourth, environment and activity participation are modifiable factors which have greater potential to strengthen older LTC residents’ mental health, and activity participation should be considered in the link between environment and mental health. A combination of enhanced physical, social, and attitudinal environments, and continual engagement in various activities may optimize older LTC residents’ mental health.

Keywords: activity, environment, mental health, older LTC residents

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18236 An Active Rectifier with Time-Domain Delay Compensation to Enhance the Power Conversion Efficiency

Authors: Shao-Ku Kao

Abstract:

This paper presents an active rectifier with time-domain delay compensation to enhance the efficiency. A delay calibration circuit is designed to convert delay time to voltage and adaptive control on/off delay in variable input voltage. This circuit is designed in 0.18 mm CMOS process. The input voltage range is from 2 V to 3.6 V with the output voltage from 1.8 V to 3.4 V. The efficiency can maintain more than 85% when the load from 50 Ω ~ 1500 Ω for 3.6 V input voltage. The maximum efficiency is 92.4 % at output power to be 38.6 mW for 3.6 V input voltage.

Keywords: wireless power transfer, active diode, delay compensation, time to voltage converter, PCE

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18235 Narrating Irish Identity: Retrieving ‘Irishness’ in the Works of William Butler Yeats and Seamus Heaney

Authors: Rafik Massoudi

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Irish identity continues to be discussed in various fields including social science, culture, literary humanities as well as political debates. In this context, Irishness had been usurped for a long time by the hegemonic power of the British Empire. That is why, Irish writers, in general, and Seamus Heaney along with William Butler Yeats, in particular, endeavored to retrieve this lost identity by shedding light on Irish history, folklore, communal traditions, landscape, indigenous people, language as well as culture. In this context, we may speak of a decolonizing attempt that allowed these writers to represent the autonomous Irish subjectivity by establishing an ethical relationship based on an extraordinary approach to the represented alterity. This article, indeed, places itself within the arena of postmodern, postcolonial discussions of the issue of identity and, particularly, of Irishness.

Keywords: identity, Irishess, narration, postcolonialism

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18234 Viability Analysis of a Centralized Hydrogen Generation Plant for Use in Oil Refining Industry

Authors: C. Fúnez Guerra, B. Nieto Calderón, M. Jaén Caparrós, L. Reyes-Bozo, A. Godoy-Faúndez, E. Vyhmeister

Abstract:

The global energy system is experiencing a change of scenery. Unstable energy markets, an increasing focus on climate change and its sustainable development is forcing businesses to pursue new solutions in order to ensure future economic growth. This has led to the interest in using hydrogen as an energy carrier in transportation and industrial applications. As an energy carrier, hydrogen is accessible and holds a high gravimetric energy density. Abundant in hydrocarbons, hydrogen can play an important role in the shift towards low-emission fossil value chains. By combining hydrogen production by natural gas reforming with carbon capture and storage, the overall CO2 emissions are significantly reduced. In addition, the flexibility of hydrogen as an energy storage makes it applicable as a stabilizer in the renewable energy mix. The recent development in hydrogen fuel cells is also raising the expectations for a hydrogen powered transportation sector. Hydrogen value chains exist to a large extent in the industry today. The global hydrogen consumption was approximately 50 million tonnes (7.2 EJ) in 2013, where refineries, ammonia, methanol production and metal processing were main consumers. Natural gas reforming produced 48% of this hydrogen, but without carbon capture and storage (CCS). The total emissions from the production reached 500 million tonnes of CO2, hence alternative production methods with lower emissions will be necessary in future value chains. Hydrogen from electrolysis is used for a wide range of industrial chemical reactions for many years. Possibly, the earliest use was for the production of ammonia-based fertilisers by Norsk Hydro, with a test reactor set up in Notodden, Norway, in 1927. This application also claims one of the world’s largest electrolyser installations, at Sable Chemicals in Zimbabwe. Its array of 28 electrolysers consumes 80 MW per hour, producing around 21,000 Nm3/h of hydrogen. These electrolysers can compete if cheap sources of electricity are available and natural gas for steam reforming is relatively expensive. Because electrolysis of water produces oxygen as a by-product, a system of Autothermal Reforming (ATR) utilizing this oxygen has been analyzed. Replacing the air separation unit with electrolysers produces the required amount of oxygen to the ATR as well as additional hydrogen. The aim of this paper is to evaluate the technical and economic potential of large-scale production of hydrogen for oil refining industry. Sensitivity analysis of parameters such as investment costs, plant operating hours, electricity price and sale price of hydrogen and oxygen are performed.

Keywords: autothermal reforming, electrolyser, hydrogen, natural gas, steam methane reforming

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18233 Performance Evaluation of a Spouted Bed Bioreactor (SBBR) for the Biodegradation of 2, 4 Dichlorophenol

Authors: Taghreed Al-Khalid, Muftah El-Naas

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As an economical and environmentally friendly technology, biological treatment has been shown to be one of the most promising approaches for the removal of numerous types of organic water pollutants such as Chlorophenols, which are hazardous pollutants commonly encountered in wastewater generated by the petroleum and petrochemical industries. This study aimed at evaluating the performance of a spouted bed bioreactor (SBBR) for aerobic biodegradation of 2, 4 dichlorophenol (DCP) by a commercial strain of Pseudomonas putida immobilized in polyvinyl alcohol (PVA) gel particles. The SBBR is characterized by systematic intense mixing, resulting in improvement of the biodegradation rates through reducing the mass transfer limitations. The reactor was evaluated in both batch and continuous mode in order to evaluate its hydrodynamics in terms of stability and response to shock loads. The SBBR was able to maintain a stable operation and recovered quickly to its normal operating mode once the shock load had been removed. In comparison to a packed bed reactor bioreactor, the SBBR proved to be more efficient and more stable, achieving a removal percentage and throughput of 80% and 1414 g/m3day, respectively. In addition, the biodegradation of chlorophenols was mathematically modeled using a dynamic modeling approach in order to assess reaction and mass transfer limitations. The results confirmed the effectiveness of the use of the PVA immobilization technique for the biodegradation of phenols.

Keywords: biodegradation, 2, 4 dichlorophenol, immobilization, polyvinyl alcohol (PVA) gel

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18232 Obtaining Composite Cotton Fabric by Cyclodextrin Grafting

Authors: U. K. Sahin, N. Erdumlu, C. Saricam, I. Gocek, M. H. Arslan, H. Acikgoz-Tufan, B. Kalav

Abstract:

Finishing is an important part of fabric processing with which a wide range of features are imparted to greige or colored fabrics for various end-uses. Especially, by the addition or impartation of nano-scaled particles to the fabric structure composite fabrics, a kind of composite materials can be acquired. Composite materials, generally shortened as composites or in other words composition materials, are engineered or naturally occurring materials made from two or more component materials with significantly different physical, mechanical or chemical characteristics remaining separate and distinctive at the macroscopic or microscopic scale within the end product structure. Therefore, the technique finishing which is one of the fundamental methods to be applied on fabrics for obtainment of composite fabrics with many functionalities was used in the current study with the same purpose. However, regardless of the finishing materials applied, the efficient life of finished product on offering desired feature is low, since the durability of finishes on the material is limited. Any increase in durability of these finishes on textiles would enhance the life of use for textiles, which will result in happier users. Therefore, in this study, since higher durability was desired for the finishing materials fixed on the fabrics, nano-scaled hollow structured cyclodextrins were chemically imparted by grafting to the structure of conventional cotton fabrics by the help of finishing technique in order to be fixed permanently. By this way, a processed and functionalized base fabric having potential to be treated in the subsequent processes with many different finishing agents and nanomaterials could be obtained. Henceforth, this fabric can be used as a multi-functional fabric due to the encapturing ability of cyclodextrins to molecules/particles via physical/chemical means. In this study, scoured and rinsed woven bleached plain weave 100% cotton fabrics were utilized because textiles made of cotton are the most demanded textile products in the textile market by the textile consumers in daily life. Cotton fabric samples were immersed in treating baths containing β-cyclodextrin and 1,2,3,4-butanetetracarboxylic acid and to reduce the curing temperature the catalyst sodium hypophosphite monohydrate was used. All impregnated fabric samples were pre-dried. The reaction of grafting was performed in dry state. The treated and cured fabric samples were rinsed with warm distilled water and dried. The samples were dried for 4 h and weighed before and after finishing and rinsing. Stability and durability of β-cyclodextrins on fabric surface against external factors such as washing as well as strength of functionalized fabric in terms of tensile and tear strength were tested. Presence and homogeneity of distribution of β-cyclodextrins on fabric surface were characterized.

Keywords: cotton fabric, cyclodextrine, improved durability, multifunctional composite textile

Procedia PDF Downloads 294
18231 Evaluation Method for Fouling Risk Using Quartz Crystal Microbalance

Authors: Natsuki Kishizawa, Keiko Nakano, Hussam Organji, Amer Shaiban, Mohammad Albeirutty

Abstract:

One of the most important tasks in operating desalination plants using a reverse osmosis (RO) method is preventing RO membrane fouling caused by foulants found in seawater. Optimal design of the pre-treatment process of RO process for plants enables the reduction of foulants. Therefore, a quantitative evaluation of the fouling risk in pre-treated water, which is fed to RO, is required for optimal design. Some measurement methods for water quality such as silt density index (SDI) and total organic carbon (TOC) have been conservatively applied for evaluations. However, these methods have not been effective in some situations for evaluating the fouling risk of RO feed water. Furthermore, stable management of plants will be possible by alerts and appropriate control of the pre-treatment process by using the method if it can be applied to the inline monitoring system for the fouling risk of RO feed water. The purpose of this study is to develop a method to evaluate the fouling risk of RO feed water. We applied a quartz crystal microbalance (QCM) to measure the amount of foulants found in seawater using a sensor whose surface is coated with polyamide thin film, which is the main material of a RO membrane. The increase of the weight of the sensor after a certain length of time in which the sample water passes indicates the fouling risk of the sample directly. We classified the values as “FP: Fouling Potential”. The characteristics of the method are to measure the very small amount of substances in seawater in a short time: < 2h, and from a small volume of the sample water: < 50mL. Using some RO cell filtration units, a higher correlation between the pressure increase given by RO fouling and the FP from the method than SDI and TOC was confirmed in the laboratory-scale test. Then, to establish the correlation in the actual bench-scale RO membrane module, and to confirm the feasibility of the monitoring system as a control tool for the pre-treatment process, we have started a long-term test at an experimental desalination site by the Red Sea in Jeddah, Kingdom of Saudi Arabia. Implementing inline equipment for the method made it possible to measure FP intermittently (4 times per day) and automatically. Moreover, for two 3-month long operations, the RO operation pressure among feed water samples of different qualities was compared. The pressure increase through a RO membrane module was observed at a high FP RO unit in which feed water was treated by a cartridge filter only. On the other hand, the pressure increase was not observed at a low FP RO unit in which feed water was treated by an ultra-filter during the operation. Therefore, the correlation in an actual scale RO membrane was established in two runs of two types of feed water. The result suggested that the FP method enables the evaluation of the fouling risk of RO feed water.

Keywords: fouling, monitoring, QCM, water quality

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18230 Movement of Metallic Inclusions in the Volume of Synthetic Diamonds at High Pressure and High Temperature in the Temperature Gradient Field

Authors: P. I. Yachevskaya, S. A. Terentiev, M. S. Kuznetsov

Abstract:

Several synthetic HPHT diamonds with metal inclusions have been studied. To have possibility of investigate the movement and transformation of the inclusions in the volume of the diamond the samples parallele-piped like shape has been made out of diamond crystals. The calculated value of temperature gradient in the samples of diamond which was placed in high-pressure cell was about 5-10 grad/mm. Duration of the experiments was in range 2-16 hours. All samples were treated several times. It has been found that the volume (dimensions) of inclusions, temperature, temperature gradient and the crystallographic orientation of the samples in the temperature field affects the movement speed of inclusions. Maximum speed of inclusions’ movement reached a value 150 µm/h.

Keywords: diamond, inclusions, temperature gradient, HPHT

Procedia PDF Downloads 507
18229 Relationship between Food Inflation and Agriculture Lending Rate in Ghana: A Vector Autoregressive Approach

Authors: Raymond K. Dziwornu

Abstract:

Lending rate of agriculture loan has persistently been high and attributed to risk in the sector. This study examined how food inflation and agriculture lending rate react to each other in Ghana using vector autoregressive approach. Quarterly data from 2006 to 2018 was obtained from the Bank of Ghana quarterly bulletin and the Ghana Statistical Service reports. The study found that a positive standard deviation shock to food inflation causes lending rate of agriculture loan to react negatively in the short run, but positively and steadily in the long run. This suggests the need to direct appropriate policy measures to reduce food inflation and consequently, the cost of credit to the agricultural sector for its growth.

Keywords: food inflation, agriculture, lending rate, vector autoregressive, Ghana

Procedia PDF Downloads 144
18228 A Review: Recycled Materials Used in Construction

Authors: Oghenerukome Akponovo, Lynda I. Onyebuchukwu

Abstract:

Construction waste, along with that of many other industries, contributes significantly to the world's annual solid waste totals. Most of these materials, such as ash from rice hulls, slags, cement kiln dust, tire ash, plastic waste (PW), and silica fumes, end up in landfills or waterways. Some of them might even end up polluting the air from high in the atmosphere. It's sustainable, cheap, and environmentally friendly to recycle these items into new building supplies. When constructing a "Green" structure, the materials employed have the potential to either exacerbate environmental imbalance or maintain a stable ecosystem. The purpose of this research is to take stock of what is already known about recycling's potential in the construction industry and to identify its deficiencies. Therefore, this study systematically reviews the wide range of recycled materials that go into building construction. Recognizing that the construction industry's use of recycled materials has an influence on the environment and that investigating these materials may have a substantial economic impact if they were discovered

Keywords: building, construction, recycled materials, waste management

Procedia PDF Downloads 99
18227 Adapting Cyber Physical Production Systems to Small and Mid-Size Manufacturing Companies

Authors: Yohannes Haile, Dipo Onipede, Jr., Omar Ashour

Abstract:

The main thrust of our research is to determine Industry 4.0 readiness of small and mid-size manufacturing companies in our region and assist them to implement Cyber Physical Production System (CPPS) capabilities. Adopting CPPS capabilities will help organizations realize improved quality, order delivery, throughput, new value creation, and reduced idle time of machines and work centers of their manufacturing operations. The key metrics for the assessment include the level of intelligence, internal and external connections, responsiveness to internal and external environmental changes, capabilities for customization of products with reference to cost, level of additive manufacturing, automation, and robotics integration, and capabilities to manufacture hybrid products in the near term, where near term is defined as 0 to 18 months. In our initial evaluation of several manufacturing firms which are profitable and successful in what they do, we found low level of Physical-Digital-Physical (PDP) loop in their manufacturing operations, whereas 100% of the firms included in this research have specialized manufacturing core competencies that have differentiated them from their competitors. The level of automation and robotics integration is low to medium range, where low is defined as less than 30%, and medium is defined as 30 to 70% of manufacturing operation to include automation and robotics. However, there is a significant drive to include these capabilities at the present time. As it pertains to intelligence and connection of manufacturing systems, it is observed to be low with significant variance in tying manufacturing operations management to Enterprise Resource Planning (ERP). Furthermore, it is observed that the integration of additive manufacturing in general, 3D printing, in particular, to be low, but with significant upside of integrating it in their manufacturing operations in the near future. To hasten the readiness of the local and regional manufacturing companies to Industry 4.0 and transitions towards CPPS capabilities, our working group (ADMAR Working Group) in partnership with our university have been engaged with the local and regional manufacturing companies. The goal is to increase awareness, share know-how and capabilities, initiate joint projects, and investigate the possibility of establishing the Center for Cyber Physical Production Systems Innovation (C2P2SI). The center is intended to support the local and regional university-industry research of implementing intelligent factories, enhance new value creation through disruptive innovations, the development of hybrid and data enhanced products, and the creation of digital manufacturing enterprises. All these efforts will enhance local and regional economic development and educate students that have well developed knowledge and applications of cyber physical manufacturing systems and Industry 4.0.

Keywords: automation, cyber-physical production system, digital manufacturing enterprises, disruptive innovation, new value creation, physical-digital-physical loop

Procedia PDF Downloads 136
18226 Investigating Sediment-Bound Chemical Transport in an Eastern Mediterranean Perennial Stream to Identify Priority Pollution Sources on a Catchment Scale

Authors: Felicia Orah Rein Moshe

Abstract:

Soil erosion has become a priority global concern, impairing water quality and degrading ecosystem services. In Mediterranean climates, following a long dry period, the onset of rain occurs when agricultural soils are often bare and most vulnerable to erosion. Early storms transport sediments and sediment-bound pollutants into streams, along with dissolved chemicals. This results in loss of valuable topsoil, water quality degradation, and potentially expensive dredged-material disposal costs. Information on the provenance of fine sediment and priority sources of adsorbed pollutants represents a critical need for developing effective control strategies aimed at source reduction. Modifying sediment traps designed for marine systems, this study tested a cost-effective method to collect suspended sediments on a catchment scale to characterize stream water quality during first-flush storm events in a flashy Eastern Mediterranean coastal perennial stream. This study investigated the Kishon Basin, deploying sediment traps in 23 locations, including 4 in the mainstream and one downstream in each of 19 tributaries, enabling the characterization of sediment as a vehicle for transporting chemicals. Further, it enabled direct comparison of sediment-bound pollutants transported during the first-flush winter storms of 2020 from each of 19 tributaries, allowing subsequent ecotoxicity ranking. Sediment samples were successfully captured in 22 locations. Pesticides, pharmaceuticals, nutrients, and metal concentrations were quantified, identifying a total of 50 pesticides, 15 pharmaceuticals, and 22 metals, with 16 pesticides and 3 pharmaceuticals found in all 23 locations, demonstrating the importance of this transport pathway. Heavy metals were detected in only one tributary, identifying an important watershed pollution source with immediate potential influence on long-term dredging costs. Simultaneous sediment sampling at first flush storms enabled clear identification of priority tributaries and their chemical contributions, advancing a new national watershed monitoring approach, facilitating strategic plan development based on source reduction, and advancing the goal of improving the farm-stream interface, conserving soil resources, and protecting water quality.

Keywords: adsorbed pollution, dredged material, heavy metals, suspended sediment, water quality monitoring

Procedia PDF Downloads 102
18225 Insights into the Perception of Sustainable Technology Adoption among Malaysian Small and Medium-Sized Enterprises

Authors: Majharul Talukder, Ali Quazi

Abstract:

The use of sustainable technology is being increasingly driven by the demand for saving resources, long-term cost savings, and protecting the environment. A transitional economy such as Malaysia is an example where traditional technologies are being replaced by sustainable ones. The antecedents that are driving Malaysian SMEs to integrate sustainable technology into their business operations have not been well researched. This paper addresses this gap in our knowledge through an examination of attitudes and ethics as antecedents of acceptance of sustainable technology among Malaysian SMEs. The database comprised 322 responses that were analysed using the PLS-SEM path algorithm. Results indicated that effective and altruism attitudes have high predictive ability for the usage of sustainable technology in Malaysian SMEs. This paper identifies the implications of the findings, along with the major limitations of the research and explores future areas of research in this field.

Keywords: sustainable technology, innovation management, Malaysian SMEs, organizational attitudes and ethical belief

Procedia PDF Downloads 327