Search results for: long term evolution

Authors: Soheila Sadeghi

Abstract:

In construction projects, predicting project performance metrics accurately is essential for effective management and successful delivery. However, conventional methods often depend on fixed baseline plans, disregarding the evolving nature of project progress and external influences. To address this issue, we introduce a distinct approach based on machine learning to forecast key performance indicators, such as cost variance and earned value, for each Work Breakdown Structure (WBS) category within an urban road reconstruction project. Our proposed model leverages time series forecasting techniques, namely Autoregressive Integrated Moving Average (ARIMA) and Long Short-Term Memory (LSTM) networks, to predict future performance by analyzing historical data and project progress. Additionally, the model incorporates external factors, including weather patterns and resource availability, as features to improve forecast accuracy. By harnessing the predictive capabilities of machine learning, our performance forecasting model enables project managers to proactively identify potential deviations from the baseline plan and take timely corrective measures. To validate the effectiveness of the proposed approach, we conduct a case study on an urban road reconstruction project, comparing the model's predictions with actual project performance data. The outcomes of this research contribute to the advancement of project management practices in the construction industry by providing a data-driven solution for enhancing project performance monitoring and control.

Keywords: project performance forecasting, machine learning, time series forecasting, cost variance, schedule variance, earned value management

Procedia PDF Downloads 39

Authors: Sandrieli Afornali, Adriano Keijiro Maeda, Renato Fedatto Beraldo, Carlos Alberto Mattozo, Ricardo Nascimento Brito

Abstract:

BACKGROUND: The most used variety in hydrocephalus treatment is the ventriculoperitoneal shunt (VPS). However, it may fails in 20 to 70% of cases. It makes necessary to have alternative cavities for the implantation of the distal catheter. Ventriculo-atrial shunting (VAS) is described as the second option. To our knowledge, there are 121 reported cases of VGB shunt in children until 2020 and a highly variable success rate, from 25 to 100%, with an average of 63% of patients presenting good long-term results. Our goal is to evaluate the epidemiological profile of patients submitted to ventriculo-gallbladder (VGB) shunt and, through a review of literature, to compare our results with others series. METHODS: a retrospective cross-sectional observational study of a case series of nine patients. The medical records of all patients were reviewed, who underwent VGB shunt at the Hospital Pequeno Príncipe from Curitiba, Paraná, Brazil, from January 2014 to October 2022. The inclusion criteria were: patients under 17 years of age with hydrocephalus of any etiology, currently using or prior to VGB shunt. RESULTS: There were 6 (66,7%) male and 3 (33,3%) female. The average age of 73.6 months or 6.1 years at the time of surgery. They were submitted on average 5.1 VPS reviews previous to VGB shunt. Five (55,5%) had complications of VGB shunt: infection (11.1%), atony (11.1%), hypodrainage due to kinking the distal catheter in the solution (11.1%) and ventriculoenteric fistula (22.2%); all these patients were cured at surgical reapproach, and in 2 of them the VGB shunt was reimplanted. Two patients died (22.2%), and five (55,5%) patients maintained the use of VGB shunt in the follow-up period; and in 4 (44.4%) there was never need for review. CONCLUSION: VGB shunt tends to be underestimated because it is still unconventional and little publicized in literature. Our article shows a lower risk of death and similar risk of complications when compared to others altenatives shunts. We emphasize VGB shunt as a safe procedure to be the second option when VPS fails or has contraindications.

Keywords: hydrocephalus, ventricular-gallbladder shunt, VGB shunt, VPS, ventriculoperitoneal shunt, ventriculoatrial shunt

Procedia PDF Downloads 72

Authors: Fadwa Chtioui

Abstract:

Vital Pulp Therapy (VPT) is nowadays challenging the deep-rooted dogma of root canal treatment, being the only therapeutic option for permanent teeth diagnosed with irreversible pulpitis or carious pulp exposure. Histologic and clinical research has shown that compromised dental pulp can be treated without the full removal or excavation of all healthy pulp, and the outcome of the partial or full pulpotomy followed by a Tricalcium-Silicate-based dressing seems to show promising results in maintaining pulp vitality and preserving affected teeth in the long term. By reviewing recent advances in the techniques of VPT and their clinical effectiveness and safety in permanent teeth with irreversible Pulpitis, this work provides a new understanding of pulp pathophysiology and defense mechanisms and will reform dental practitioners' decision-making in treating irreversible pulpits from root canal therapy to vital pulp therapy by taking advantage of the biological effects of Tricalcium Silicate materials. Biography of presenting author: Fadwa Chitoui graduated from the school of Dental Medicine of Monastir, Tunisia, in 2015. After getting her DDS degree with honors, she earned her Postgraduate master's Degree in Endodontics and Restorative Dentistry from her Faculty. Since 2021, she has Started her own private and specialized practice based in the capital Tunis. She enjoys the sphere of associative life, worked with national and international associations, and got engaged in scientific dental research, whereby she tailored her passion for her field of specialty towards broadening her knowledge and ambitions, holding conferences and workshops nationally and internationally and publishing scientific articles in several journals.

Keywords: irreversible pulpitis, permanenet teeth, vital pulp therapy, pulpotomy

Procedia PDF Downloads 68

Authors: Azaz Zaman, Mirazur Rahman

Abstract:

Capital market is a crucial financial market place where companies and the government can raise long-term funds and, at the same time, investors get the opportunity to invest in the listed companies. Capital markets play a vital role not only in shifting the funds from surplus entity to deficit for investment, but also in the overall economic development of any developing country like Bangladesh. Being the first and biggest capital market of Bangladesh, Dhaka Stock Exchange (DSE) is the prime bourse of the country. The differences in the investment preference— among three broad categories of investors in DSE including individual investors, institutional investors, and government— are easily observed. Authors of this article have used five categories of investors such as sponsors or directors of the company, institutional investors, foreign investors, government, and the general public in order to present a comparative analysis of their investment patterns. Obtaining data on the percentage of investment by these five types of investors in different sectors from the DSE website, this study aims to analyze the sector-wise investment preference of these investors using August 2018 data. The study has found that the sponsors or directors of the company have the highest percentage of investment in the textile industry which is close to 16%. The Bangladesh government, as an investor, has the highest percentage of investment in the fuel & power sector, approximately 32%. It has also found that the mutual funds' sector is mostly financed by institutional investors, nearly 28%. Foreign investors have their most investments in the banking sector, which is close to 22%. It has also revealed that the textile sector is mostly financed by the general public, close to 17%. Nevertheless, general public, surprisingly, has the lowest percentage of investment in the telecommunication sector, which is 0.10%.

Keywords: stock market investment, Dhaka stock exchange, capital market, Bangladesh

Procedia PDF Downloads 119

Authors: Farrah Anne Robert, Robert McClelland, Seng Kiat Kok

Abstract:

Higher education service quality is widely regarded as key factors in the long term success of a higher education institution in attracting and retaining students. This research attempted to establish the impact of service quality on recruiting and retaining students in private higher education institutions (PHEI’s). 501 local and international students responded to a 49 item educational service measure questionnaire from PHEIs in Kuala Lumpur and Selangor, two states in Malaysia which together account for 60% of private colleges in Malaysia. Results from this research revealed that, inter-alia, facilities, employability, management and administration services, academic staff competence, curriculum and student overall experiences were key driving factors in attracting and retaining students. Lack of “campus-like building” facilities and lecturer’s effectiveness in delivering lectures were keys concerns in the provision of service quality by PHEI’s in Malaysia. Over the last decade, the Government of Malaysia has set a target of recruiting 200,000 international students to study in Malaysia by PHEI’s and PHEI’s have failed to achieve this target. This research suggests that service quality issues identified above are impacting efforts to recruit and retain both local and international students by PHEIs. The researcher recommends that further and detailed research be carried on these factors and its impact on recruitment and retention. PHEI administrators can benefit from this research by conducting an evaluation of service measures delivered in their institutions and take corrective measures. Prospective students can benefit from this study by including in their choice factors the “service quality delivery” of PHEI’s when deciding to enroll in a particular PHEI.

Keywords: higher education, recruitment, retention, service quality

Procedia PDF Downloads 378

Authors: Nivatha Elangovan, Lakshman Neelakantan, Murugaiyan Amirthalingam

Abstract:

Magnesium and its alloys are widely used for various lightweight engineering and biomedical applications as they render high strength to low weight ratio and excellent corrosion resistance. These alloys possess good bio-compatibility and similar mechanical properties to natural bone. However, manufacturing magnesium alloy components by conventional formative and subtractive methods is challenging due to their poor castability, oxidation potential, and machinability. Therefore, efforts are made to produce complex-design containing magnesium alloy components by additive manufacturing (AM). Arc-wire directed energy deposition (AW-DED), also known as wire arc additive manufacturing (WAAM), is more attractive to produce large volume components with increased productivity than any other AM technique. In this research work, efforts were made to optimise the deposition parameters to build thick-walled (about 10 mm) AZ31 magnesium alloy components by a gas metal arc (GMA) based AW-DED process. By using controlled dip short-circuiting metal transfer in a GMA process, depositions were carried out without defects and spatter formation. Current and voltage waveforms were suitably modified to achieve stable metal transfer. Moreover, the droplet transfer behaviour was analysed using high-speed image analysis and correlated with arc energy. Optical and scanning electron microscopy analyses were carried out to correlate the influence of deposition parameters with the microstructural evolution during deposition. The investigation reveals that by carefully controlling the current-voltage waveform and droplet transfer behaviour, it is possible to stabilise equiaxed grain microstructures in the deposited AZ31 components. The printed component exhibited an improved mechanical property as equiaxed grains improve the ductility and enhance the toughness. The equiaxed grains in the component improved the corrosion-resistant behaviour of other conventionally manufactured components.

Keywords: arc wire directed energy deposition, AZ31 magnesium alloy, equiaxed grain, corrosion

Procedia PDF Downloads 124

Authors: Xiaoya Yi, Yi He, Zhao Lu, Yang Zhang

Abstract:

In the process of rapid urbanization, many historical cities have undergone excessive demolition and construction under the protection and renewal mechanism. The original pattern of the city has been changed, the urban context has been cut off, and historical features have gradually been lost. The historical city gradually changed into the form of decentralization and fragmentation. The understanding of the ancient city includes two levels. The first one refers to the ancient city on the physical space, which defined an ancient city by its historic walls. The second refers to the public perception of the image, which is derived from people's spatial identification of the ancient city. In ancient China, people draw maps to show their way of understanding the city. Starting from ancient maps and exploring the spatial characteristics of traditional Chinese cities from the perspective of urban imagery is a key clue to understanding the spatial characteristics of historical cities on an overall level. The spatial characteristics of the urban image presented by the ancient map are summarized into two levels by typology. The first is the spatial pattern composed of the center, axis and boundary. The second is the space element that contains the city, street, and sign system. Taking the ancient city of Shipu as a typical case, the "city image" in the ancient map is analyzed as a prototype, and it is projected into the current urban space. The research found that after a long period of evolution, the historical spatial pattern of the ancient city has changed from “dominant” to “recessive control”, and the historical spatial elements are non-centralized and fragmented. The wall that serves as the boundary of the ancient city is transformed into “fragmentary remains”, the streets and lanes that serve as the axis of the ancient city are transformed into “structural remains”, and the symbols of the ancient city center are transformed into “site remains”. Based on this, the paper proposed the methods of controlling the protection of land boundaries, the protecting of the streets and lanes, and the selective restoring of the city wall system and the sign system by accurate assessment. In addition, this paper emphasizes the continuity of the ancient city's traditional spatial pattern and attempts to explore a holistic conservation method of the ancient city in the modern context.

Keywords: ancient city protection, ancient maps, Shipu ancient city, urban intention

Procedia PDF Downloads 128

Authors: Arsalan Salahi

Abstract:

Today, the number of changes in the construction industry and urban mass house building is increasing, which makes you need to pay more attention to targeted planning for human resource management and training. The human resources working in the construction industry have various problems and deficiencies, and in order to solve these problems, there is a need for basic management and training of these people in order to lower the construction costs and increase the quality of the projects, especially in mass house building projects. The success of any project in reaching short and long-term professional goals depends on the efficient combination of work tools, financial resources, raw materials, and most importantly, human resources. Today, due to the complexity and diversity of each project, specialized management fields have emerged to maximize the potential benefits of each component of that project. Human power is known as the most important resource in construction projects for its successful implementation, but unfortunately, due to the low cost of human power compared to other resources, such as materials and machinery, little attention is paid to it. With the correct management and training of human resources, which depends on its correct planning and development, it is possible to improve the performance of construction projects. In this article, the training and motivation of construction industry workers and their effects on the effectiveness of projects in this industry have been researched. In this regard, some barriers to the training and motivation of construction workers and personnel have been identified and solutions have been provided for construction companies. Also, the impact of workers and unskilled people on the efficiency of construction projects is investigated. The results of the above research show that by increasing the use of correct and basic training for human resources, we will see positive results and effects on the performance of construction projects.

Keywords: human resources, construction industry, principled training, skilled and unskilled workers

Procedia PDF Downloads 95

Authors: Said Algarni

Abstract:

The purpose of this study was to investigate selected numerical methods that demonstrate good performance in solving PDEs. We adapted alternative method that involve rational polynomials. Padé time stepping (PTS) method, which is highly stable for the purposes of the present application and is associated with lower computational costs, was applied. Furthermore, PTS was modified for our study which focused on diffusion equations. Numerical runs were conducted to obtain the optimal local error control threshold.

Keywords: Padé time stepping, finite difference, reaction diffusion equation, PDEs

Procedia PDF Downloads 299

Authors: Heide Imai

Abstract:

Contemporary cities, especially in Japan, have reached an indescribable complexity and excessive, global investments blur formal, rooted structures. Modern urban agglomerations blindly trust a macro understanding, whereas everyday activities which portray the human degree of living space are being suppressed and erased. The paper will draw upon the approach ‘Micro-Urbanism’ which focus on the sensitive and indigenous side of contemporary cities, which in fact can hold the authentic qualities of a city. Related to this approach is the term ‘Micro-Culture’ which is used to clarify the inner realities of the everyday living space on the example of the Japanese urban backstreet. The paper identifies an example of a ‘micro-zone’ in terms of ‘street space’, originally embedded in the landscape of the Japanese city. And although the approach ‘Micro-Urbanism’ is more complex, the understanding of the term can be tackled by a social analysis of the street, as shown on the backstreet called roji and closely linked examples of ‘situated’ urban rituals like (1) urban festivities, (2) local markets/ street vendors and (3) artistic, intellectual tactics. Likewise, the paper offers insights in a ‘community of streets’ which boundaries are specially shaped by cultural activity and social networks.

Keywords: urban rituals, community, streets as micro-zone, everyday space

Procedia PDF Downloads 311

Authors: Stephanie Nihan, Jayson M. Fadrigalan, Pyay P. San, Steven M. Santos, Weihui Li

Abstract:

People of all ages who use wheelchairs are left with the inconvenience of not having an easy way to take their vital signs. Typically, patients are required to visit the hospital in order to take the vital signs. VitalGO is a wheel chair system that equipped with medical devices to take vital signs and then transmit data to a mobile application for convenient, long term health monitoring. The vital signs include oxygen saturation, heart rate, and blood pressure, breathing rate and body temperature. Oxygen saturation and heart rate are monitored through pulse oximeter. Blood pressure is taken through a radar sensor. Breathing rate is derived through thoracic impedance while body temperature is measured through an infrared thermometer. The application receives data through bluetooth and stores in a database for review in a simple graphical interface. The application will have the ability to display this data over various time intervals such as a day, week, month, 3 months, 6 months and a year. The final system for the mobile app can also provide an interface for both the user and their physician(s) to record notes or keep record of daily symptoms that a patient might be having. The user’s doctor will be granted access by the user to view the patient information for assistance with a more accurate diagnosis. Also, this wheelchair accessory conveniently includes a foldable table/desk as somewhere to place an electronic device that may be used to access the app. The foldable table will overall contribute to the wheelchair user’s increased comfort and will give them somewhere to place food, a book, or any other form of entertainment that would normally be hard to juggle on their lap.

Keywords: wheel chair, vital sign, mobile application, telemedicine

Procedia PDF Downloads 331

Authors: Wei-Jing Li, Ren-Xuan Yang, Kui-Hao Chuang, Ming-Yen Wey

Abstract:

Nowadays, plastic product and utilization are extensive and have greatly improved our life. Yet, plastic wastes are stable and non-biodegradable challenging issues to the environment. Waste-to-energy strategies emerge a promising way for waste management. This work investigated the co-production of hydrogen and carbon nanotubes from the syngas which was from the gasification of polypropylene. A nickel-silica core-shell catalyst was applied for syngas reaction from plastic waste gasification in a fixed-bed reactor. SiO2 were prepared through various synthesis solvents by Stöber process. Ni plays a role as modified SiO2 support, which were synthesized by deposition-precipitation method. Core-shell catalysts have strong interaction between active phase and support, in order to avoid catalyst sintering. Moreover, Fe or Co metal acts as promoter to enhance catalytic activity. The effects of calcined atmosphere, second metal addition, and reaction temperature on hydrogen production and carbon yield were examined. In this study, the catalytic activity and carbon yield results revealed that the Ni/SiO2 catalyst calcined under H2 atmosphere exhibited the best performance. Furthermore, Co promoted Ni/SiO2 catalyst produced 3 times more than Ni/SiO2 on carbon yield at long-term operation. The structure and morphological nature of the calcined and spent catalysts were examined using different characterization techniques including scanning electron microscopy, transmission electron microscopy, X-ray diffraction. In addition, the quality and thermal stability of the nano-carbon materials were also evaluated by Raman spectroscopy and thermogravimetric analysis.

Keywords: plastic wastes, hydrogen, carbon nanotube, core-shell catalysts

Procedia PDF Downloads 319

Authors: Abdulmalik Altuwayjiri, Milad Pirhadi, Sina Taghvaee, Constantinos Sioutas

Abstract:

A significant portion of PM₂.₅ mass concentration is carbonaceous matter (CM), which majorly exists in the form of organic carbon (OC). Ambient OC originates from a multitude of sources and plays an important role in global climate effects, visibility degradation, and human health. In this study, positive matrix factorization (PMF) was utilized to identify and quantify the long-term contribution of PM₂.₅ sources to total OC mass concentration in central Los Angeles (CELA) and Riverside (i.e., receptor site), using the chemical speciation network (CSN) database between 2005 and 2015, a period during which several state and local regulations on tailpipe emissions were implemented in the area. Our PMF resolved five different factors, including tailpipe emissions, non-tailpipe emissions, biomass burning, secondary organic aerosol (SOA), and local industrial activities for both sampling sites. The contribution of vehicular exhaust emissions to the OC mass concentrations significantly decreased from 3.5 µg/m³ in 2005 to 1.5 µg/m³ in 2015 (by about 58%) at CELA, and from 3.3 µg/m³ in 2005 to 1.2 µg/m³ in 2015 (by nearly 62%) at Riverside. Additionally, SOA contribution to the total OC mass, showing higher levels at the receptor site, increased from 23% in 2005 to 33% and 29% in 2010 and 2015, respectively, in Riverside, whereas the corresponding contribution at the CELA site was 16%, 21% and 19% during the same period. The biomass burning maintained an almost constant relative contribution over the whole period. Moreover, while the adopted regulations and policies were very effective at reducing the contribution of tailpipe emissions, they have led to an overall increase in the fractional contributions of non-tailpipe emissions to total OC in CELA (about 14%, 28%, and 28% in 2005, 2010 and 2015, respectively) and Riverside (22%, 27% and 26% in 2005, 2010 and 2015), underscoring the necessity to develop equally effective mitigation policies targeting non-tailpipe PM emissions.

Keywords: PM₂.₅, organic carbon, Los Angeles megacity, PMF, source apportionment, non-tailpipe emissions

Procedia PDF Downloads 198

Authors: Abiodun Musbau Lawal, Benjamin Oladapo Olley

Abstract:

Long Distance Truck Drivers (LDTDs) have been found to be a high-risk group in the spread of HIV/AIDS globally; perhaps, due to their high Sexual Risk Behaviours (SRBs). Interventions for reducing SRBs in trucking population have not been fully exploited. A quasi-experimental control group pretest-posttest design was used to assess the efficacy of psycho-education and behavioural skills training in reducing SRBs among LDTDs. Sixteen drivers rivers were randomly assigned into either experimental or control groups using balloting technique. A questionnaire was used as an instrument for data collection. Repeated measures t-test and independent t-test were used to test hypotheses. The intervention had a significant effect on the SRBs among LDTDs at post-test(t{7}=6.01, p<.01) and at followup (t{7}=6.42, p<.01). No significant difference in sexual risk behaviour of LDTDs at post-test and at follow-up stage. Similarly, intervention had significant effects on sexual risk behaviour at post-test (t {14}=- 4.69, p<.05) and at follow-up (t {14}= -9.56, p < .05) respectively. At post-test and follow-up stages, drivers in experimental group reported reduced SRBs than those in the control group. Drivers in an experimental group reported lower sexual risk behaviour a week after intervention as well as at three months follow-up than those in the control group. It is concluded that HIV/AIDS preventive intervention that provides the necessary informational and behavioural skills content can significantly impact long distance truck drivers sexual risk behaviours.

Keywords: HIV/AIDS interventions, long distance truck drivers, Nigeria, sexual risk behaviours

Procedia PDF Downloads 476

Authors: Saniye Çeşmecioğlu

Abstract:

The importance of project sustainability and success has become increasingly significant due to the proliferation of external environmental factors that have decreased project resistance in contemporary times. The primary approach to forestall the failure of projects is to ensure their long-term viability through the strategic selection of projects as creating judicious project selection framework within the organization. Decision-makers require precise decision contexts (models) that conform to the company's business objectives and sustainability expectations during the project selection process. The establishment of a rational model for project selection enables organizations to create a distinctive and objective framework for the selection process. Additionally, for the optimal implementation of this decision-making model, it is crucial to establish a Project Management Office (PMO) team and Project Steering Committee within the organizational structure to oversee the framework. These teams enable updating project selection criteria and weights in response to changing conditions, ensuring alignment with the company's business goals, and facilitating the selection of potentially viable projects. This paper presents a multi-criteria decision model for selecting project sustainability and project success criteria that ensures timely project completion and retention. The model was developed using MACBETH (Measuring Attractiveness by a Categorical Based Evaluation Technique) and was based on broadcaster companies’ expectations. The ultimate results of this study provide a model that endorses the process of selecting the appropriate project objectively by utilizing project selection and sustainability criteria along with their respective weights for organizations. Additionally, the study offers suggestions that may ascertain helpful in future endeavors.

Keywords: project portfolio management, project selection, multi-criteria decision making, project sustainability and success criteria, MACBETH

Procedia PDF Downloads 62

Authors: Saleh Alotaibi, Mohammed Quddus, Craig Morton, Jobair Bin Alam

Abstract:

This paper explores the role of large-scale investment in transport sectors and the impact of increased railway accessibility on the efficiency of the regional economic productivity in the Kingdom of Saudi Arabia (KSA). There are considerable differences among the KSA regions in terms of their levels of investment and productivity due to their geographical scale and location, which in turn greatly affect their relative efficiency. The study used a non-parametric linear programming technique - Data Envelopment Analysis (DEA) - to measure the regional efficiency change over time and determine the drivers of inefficiency and their scope of improvement. In addition, Window DEA analysis is carried out to compare the efficiency performance change for various time periods. Malmquist index (MI) is also analyzed to identify the sources of productivity change between two subsequent years. The analysis involves spatial and temporal panel data collected from 1999 to 2018 for the 13 regions of the country. Outcomes reveal that transport investment and improved railway accessibility, in general, have significantly contributed to regional economic development. Moreover, the endowment of the new railway stations has spill-over effects. The DEA Window analysis confirmed the dynamic improvement in the average regional efficiency over the study periods. MI showed that the technical efficiency change was the main source of regional productivity improvement. However, there is evidence of investment allocation discrepancy among regions which could limit the achievement of development goals in the long term. These relevant findings will assist the Saudi government in developing better strategic decisions for future transport investments and their allocation at the regional level.

Keywords: data envelopment analysis, transport investment, railway accessibility, efficiency

Procedia PDF Downloads 149

Authors: Zeinab Gharibi, B. Stoevesandt, J. Peinke

Abstract:

Long term surface erosion of wind turbine blades, especially at the leading edge, impairs aerodynamic performance; therefore, lowers efficiency of the blades mostly in the high-speed rotor tip regions. Blade protection provides significant improvements in annual energy production, reduces costly downtime, and protects the integrity of the blades. However, this protection still influences the aerodynamic behavior, and broadband noise caused by interaction between the impinging turbulence and blade’s leading edge. This paper presents an extensive numerical aeroacoustics approach by investigating the sound power spectra of the eroded and coated NACA 64-618 wind turbine airfoil and evaluates aeroacoustics improvements after the protection procedure. Using computational fluid dynamics (CFD), different quasi 2D numerical grids were implemented and special attention was paid to the refinement of the boundary layers. The noise sources were captured and decoupled with acoustic propagation via the derived formulation of Curle’s analogy implemented in OpenFOAM. Therefore, the noise spectra were compared for clean, coated and eroded profiles in the range of chord-based Reynolds number (1.6e6 ≤ Re ≤ 11.5e6). Angle of attack was zero in all cases. Verifications were conducted for the clean profile using available experimental data. Sensitivity studies for the far-field were done on different observational positions. Furthermore, beamforming studies were done simulating an Archimedean spiral microphone array for far-field noise directivity patterns. Comparing the noise spectra of the coated and eroded geometries, results show that, coating clearly improves aerodynamic and acoustic performance of the eroded airfoil.

Keywords: computational fluid dynamics, computational aeroacoustics, leading edge, OpenFOAM

Procedia PDF Downloads 223

Authors: Oghenetega Ogodo

Abstract:

In recent years, as the nature of work and employment relations continue to evolve, the gig economy has experienced rapid growth in various parts of the world. A notable example is ride-hailing services, which offer new sources of livelihood and work for drivers and transform urban mobility. While Kate Meagher contributes to the global discourse on the need to review the social contracts of digital works in Lagos State, it is essential to investigate the influence on urban livelihoods as more organizations, governments, and policymakers integrate this as a tool for economic development. Using the snowball sampling method, this exploratory study provides data on the factors that influence the transition of workers to digital platforms (like Uber and Taxify (Bolt)), satisfaction with working conditions, and the perception as a long-term source of livelihood or a means to an end from fifty respondents in Lagos State. Although the results show the beneficial factors of operating on the platforms, the ripple effects on the livelihoods of digital and traditional transport workers are also evident in the study. A mall intercept survey also shows the level of patronage amongst users/commuters across five (5) shopping malls in Lagos State. The results indicate the role of technology in influencing the choice of commuters to use either the public transportation system or digital platforms. It is essential to promote development policies that support productive activities, decent job creation, entrepreneurship, and innovation, encourage the formalization and growth of all enterprises, ensure access to financial services, and achieve full and productive employment and decent work for all.

Keywords: informal economies, digital technology, transportation policy, economic development

Procedia PDF Downloads 9

Authors: Hsi-Chuan Wang, Hongxi Yin

Abstract:

Compactness has been proposed as a type of sustainable urban form globally. However, the meanings and the measurements might diverse in regarding to the varying interpretation; moreover, since compactness was proposed to eliminate auto culture and urban sprawl in the developed countries, voices have emerged asking to rethink the suitability of compactness in the developing countries – based upon such understanding, Quality of Life (QOL) has been suggested as a good way to show the overall benefit of compactness. In regarding to such background, two subjects were targeted for discussion in this paper: (I) the meaning and feasibility of compactness between the developing and developed countries, and (II) the interaction between compactness and QOL. This paper argues that compactness should not be considered a universal principle for cities of all kind, but rather an ideal concept for urban designer and planner to consider throughout local practices. It firstly reviewed the benefits of both compactness and sprawl to uncover the features behind these urban forms, and later addressed the meaning and difficulty of adopting compactness in both the developing and developed countries. Secondly, arguing compactness to be positioned as a ‘process’ along the transition from the developing countries to the developed ones, this paper applied both cross-sectional and longitudinal analysis to uncover (I) the relationship between compactness and QOL in regarding to 30 American cities and (II) the impact of ‘becoming compact’ on QOL in regarding to 8 identified American Urbanized Areas (UZAs). The findings indicated that higher compactness could link to lower QOL among the compact cities, but with higher QOL among the sprawl cities. In addition, based upon the comparison between 2000 and 2010 on 8 UZAs, their QOL have escalated during the transition from the sprawl areas into the compact ones, but the extent of improvement in QOL could differ greatly among areas. In regarding to our findings, compact development should be proposed as a general guideline leading the contemporary sprawl cities in transition with sustainable urbanism; however, to prevent the externalities from damaging QOL with over-compactness, the compact policy should be flexible to adjust a long-term roadmap for sustainable development.

Keywords: compactness, quality of life, sprawl, sustainable urbanism

Procedia PDF Downloads 164

Authors: Shiliang Wu, Huanxin Zhang

Abstract:

Mercury has been well-known for its negative effects on wildlife, public health as well as the ecosystem. Once emitted into atmosphere, mercury can be transformed into different forms or enter the ecosystem through dry deposition or wet deposition. Some fraction of the mercury will be reemitted back into the atmosphere and be subject to the same cycle. In addition, the relatively long lifetime of elemental mercury in the atmosphere enables it to be transported long distances from source regions to receptor regions. Global change such as climate change and land use/land cover change impose significant challenges for mercury pollution control besides the efforts to regulate mercury anthropogenic emissions. In this study, we use a global chemical transport model (GEOS-Chem) to examine the potential impacts from changes in climate and land use/land cover on the global budget of mercury as well as its atmospheric transport, chemical transformation, and deposition. We carry out a suite of sensitivity model simulations to separate the impacts on atmospheric mercury associated with changes in climate and land use/land cover. Both climate change and land use/land cover change are found to have significant impacts on global mercury budget but through different pathways. Land use/land cover change primarily increase mercury dry deposition in northern mid-latitudes over continental regions and central Africa. Climate change enhances the mobilization of mercury from soil and ocean reservoir to the atmosphere. Also, dry deposition is enhanced over most continental areas while a change in future precipitation dominates the change in mercury wet deposition. We find that 2000-2050 climate change could increase the global atmospheric burden of mercury by 5% and mercury deposition by up to 40% in some regions. Changes in land use and land cover also increase mercury deposition over some continental regions, by up to 40%. The change in the lifetime of atmospheric mercury has important implications for long-range transport of mercury. Our case study shows that changes in climate and land use and cover could significantly affect the source-receptor relationships for mercury.

Keywords: mercury, toxic pollutant, atmospheric transport, deposition, climate change

Procedia PDF Downloads 489

Authors: Ying-Ming Su, Mei-Shu Huang

Abstract:

To mitigate the urban heat island effect has become a global issue facing the challenge of climate change. Through literature reviews, plant photosynthesis can reduce the carbon dioxide and mitigate the urban heat island effect relatively. Because there are not enough open space and park, green roof has become an important policy in Taiwan. We selected elementary school buildings in northern New Taipei City as research subjects since elementary school is asked priority to build green roof and important educational place to promote green roof concept. Testo 175-H1 recording device was used to record the temperature and humidity difference between roof surface and interior space below roof with and without green roof for the long-term. We also use questionnaire to investigate the awareness of comfort level of green roof and sensation of teachers and students of the elementary school. The results indicated the temperature of roof without greening was higher than that with greening about 2°C. But sometimes during noontime, the temperature of green roof was higher than that of non-green roof related to the character of the accumulation and dissipation of heat of greening probably. The temperature of interior space below green roof was normally lower than that without green roof about 1°C showed that green roof could lower the temperature. The humidity of the green roof was higher than the one without greening also indicated that green roof retained water better. Teachers liked to combine green roof concept in the curriculum, students wished all classes can take turns to maintain the green roof. Teachers and students that school had integrated green roof concept in the curriculum were more willing to participate in the maintenance work of green roof. Teachers and students who may access and touch the green roof can be more aware of the green roof benefit. We suggest architect to increase the accessibility and visibility of green roof, such as a part of the activity space. This idea can be a reference of the green roof curriculum design.

Keywords: comfort level, elementary school, green roof, heat island effect

Procedia PDF Downloads 416

Authors: Amany Haridy, Ahmed Elseragy, Fahd Omar

Abstract:

The issue of temperature increase in the urban microclimate has been at the center of attention recently, especially in dense urban areas, such as the City of Alexandria in Egypt, where building surfaces have become the dominant element (more than green areas and streets). Temperatures have been rising during daytime as well as nighttime, however, the research focused on the rise of air temperature at night, a phenomenon known as the urban heat island. This phenomenon has many effects on ecological life, as well as human health. This study provided evidence of the possibility of reducing the urban heat island by using a green building envelope (green wall and green roof) in Alexandria, Egypt. This City has witnessed a boom in growth in its urban fabric and population. A simulation analysis using the Envi-met software to find the ratio of air temperature reduction was performed. The simulation depended on the orientation of the green areas and their density, which was defined through a process of climatic analysis made by the Diva plugin using the Grasshopper software. Results showed that the reduction in air temperature varies from 0.8–2.0 °C, increasing with the increasing density of green areas. Many systems of green wall and green roof can be found in the local market. However, treating an existing building requires a careful choice of system to fit the building construction load and the surrounding nature. Among the systems of choice, there was the ‘geometric system’ of vertical greening that can be fixed on a light aluminum structure for walls and the extensive green system for roofs. Finally, native plants were the best choice in the long term because they fare well in the local climate.

Keywords: envi-met, green building envelope, urban heat island, urban microclimate

Procedia PDF Downloads 208

Authors: Szymon Szemik, Małgorzata Kowalska

Abstract:

Objective: Medical students experience numerous demands during the education process, determining their quality of life (QoL) and health status. POLLEK (POLski LEKarz, eng. Polish Physician) study aims to identify and evaluate the quality of life, mental health status, and ever-recognized chronic diseases by simultaneously assessing their determinants in Polish medical students during long-term observation. Material and Methods: The POLLEK is the follow-up cohort study conducted among medical students at the Medical University of Silesia in Katowice. Students were followed during two observation periods: in their first year of studies, the academic year 2021/2022 (T1), and in their second year, the academic year 2022/2023 (T2). Results: The total number of participants in the first year of observation (T1) was 427 while in the second year (T2) was 335. Obtained results confirmed that the QoL score significantly decreased in their second year of studies mainly in the somatic and psychological domains. Moreover, we observed a significant increase in self-declared scoring of somatic symptoms year by year (from M=4.75 at T1 to M=8.06 at T2, p<0.001) in the GHQ-28 questionnaire survey. The determinants of QoL domains common to T1 and T2 remained self-declared health status, frequency of physical activity, and current financial situation. In the first year of evaluation, 56 students (13.10%) were overweight or obese, and 52 (15.8%) in the second. Regardless of the academic year, the increased risk of being overweight or obese was significantly associated with dissatisfaction with personal health, financial deficiencies, and a diet abundant in meat consumption. Conclusions: The QoL in medical students and selected determinants of their health status deteriorated during the observation period. Our findings suggest that medical schools should actively promote the activity needed to achieve a balance between schoolwork and the personal life of medical students from the beginning of university study.

Keywords: quality of life, mental health, medical students, follow-up study

Procedia PDF Downloads 40

Authors: Yasemin Kaya, Ahmet N. Eraslan

Abstract:

In this study, the thermoelastic behavior of a long tube is studied by taking into account the temperature dependency of all mechanical and thermal properties. As the tube is heated slowly, an uncoupled solution procedure is adopted under free and radially constrained boundary conditions. The nonlinear heat conduction equation is solved by a finite element collocation procedure and the corresponding distributions of stress and strain are computed by shooting iterations. The computational model is verified in comparison to the analytical solution by shutting down the temperature dependency of physical properties. In the analysis, experimental data available in the literature is used to describe the coefficient of thermal expansion $\alpha$, the thermal conductivity $k$, the modulus of rigidity $G$, the yield strength $\sigma_{0}$, and the Poisson's ratio $\nu$ of Nickel. Results of the analysis are presented in comparison to those having constant physical properties. As a result of the calculations, the temperature dependency of the material properties should be taken into account at higher temperature ranges.

Keywords: thermoelasticity, long tube, temperature-dependent properties, internal heating

Procedia PDF Downloads 613

Authors: Laszlo Dorner

Abstract:

Background: In the last few decades there has been a significant discussion within the researchers of prosocial behavior about to what extent personality characteristics matter in determining the quality and frequency of helping behaviors. Of these community activities the most important is formal volunteering which mainly realises in civil services and organizations. Recently many researches have been showed up regarding the personality factors and motivations behind volunteering). Most of these researches found strong correlation between Agreeableness and Extraversion as global traits and the time spent on volunteering and its frequency as well. Aims of research: In this research we investigate the relation between formal volunteer activities and global traits in a Hungarian volunteer sample. We hypothetise that the results appeared in the previous researches show the same pattern in Hungary as well: volunteering would be related to Agreeableness and Extraversion. We also assume that the time spent on volunteering is related to these traits, since these traits would serve as an indicator of long-term volunteering. Methods: We applied the Hungarian adaptation of Big Five Questionnaire created by Caprara, Barbaranelli és Borgogni. This self-reported questionnaire contains 132 items, and explore 5 main traits examining the person’s most important emotional and motivational features regarding its personality. This research took into account the most important socio-economical factors (age, gender, religiosity, income) which can determine volunteer activities per se. The data is evaluated by SPSS 19.0 Statistical Software. Sample: 92 volunteer (formal, mainly the volunteers of Hungarian Red Cross and Hospice Organizations)and 92 non volunteer person, with matched subsamples by the factors of age, gender and qualification. Results: The volunteer subsample shows higher values of Energy and significantly higher values of Agreeableness and Openness, however, regarding Conscientiousness and Emotional Stability the differences are not significant between the volunteer and non-volunteer subsamples.

Keywords: Big Five, comparative analysis, global traits, volunteering

Procedia PDF Downloads 350

Authors: Yotaro Natani

Abstract:

In his recent works, Frankfurt School theorist Axel Honneth elucidates an intersubjective notion of social freedom and outlines a vision of socialism as the realization of social freedom in the family, market economy, and public sphere. These arguments are part of his broader project of defending the tradition of immanent critique and normative reconstruction. In contrast, American Marxist sociologist Erik Olin Wright spells out a vision of socialism in terms of building real utopias -democratic, egalitarian, alternative institutions- through the exercise of civil society’s social power over the economy and state. Wright identifies ‘eroding capitalism’ as the framework for thinking about the strategic logics of gradually diminishing the dominance of capitalism. Both thinkers envision the transition toward socialism in terms of democratic experimentation; Honneth is more attentive to the immanent norms of social life, whereas Wright is better aware of the power of antagonistic structures. This paper attempts to synthesize the ideas of Honneth and Wright. It will show that Honneth’s critique of capitalism suffers from certain ambiguities because he attributes normative legitimacy to existing institutions, resulting in arguments that do not problematize aspects of capitalist structures. This paper will argue that incorporating the notion of power and thematizing the erosion of capitalism as a long-term goal for socialist change will allow Honneth to think more precisely about the conditions for realizing social freedom, in a manner that is still consistent with the immanent critique tradition. Such reformulation will result in a concept of social freedom that is less static and rooted in functional teleology and more oriented toward creative agency and experimental democracy.

Keywords: Axel Honneth, immanent critique, real utopias, social freedom, socialism

Procedia PDF Downloads 145

Authors: Keivan Amirbagheri, Ana Nuñez-Carballosa, Laura Guitart-Tarrés

Abstract:

Over the last couple of decades, enterprises have begun to accept the need for environmental management and have started to implement environmental management programs to compete in the markets. The implementation of green supply chain management (GSCM) practices can provide valuable opportunities to improve firm performance. Through the prior investigations, the ascending tendency of the numbers of published papers in the field of green supply chain management practices has been reported and it shows the high interest level of the authors to work in this area. Besides, there is still a gap to study more about the relationship of GSCM to the organizational performance (OP). So, the purpose of this research is to study the practices related to green supply chain management that influence the results of the company as an organizational performance. Based on our previous works, from one part we have collected these GSCM practices (planning, operational, and communication practices) and classified them through conducting some literature reviews to analyze their effects on the OP’s factors (balanced scorecard’s perspectives). To do so we design a case study methodology through semi-structured interviews and secondary data from some multinational well-known companies based in Spain. The cases have been selected with the criterion of trying to collect members of the entire supply chain to have a vision as global as possible. The results report the considerable influence of green supply chain management practices on the organizational performance of the companies of the study. In addition, they represent that the implementation of green supply chain management practices especially in a long-term perspective can be economically justified. From the point of view of the personal, they feel better about being a member of this type of company that has been structured on environmental issues. Also, for these companies, the image that has been created by the implementation of these practices helps them to facilitate their marketing program.

Keywords: green supply chain management, organizational performance, case study, Spain

Procedia PDF Downloads 190

Authors: Nadia Allouache, Mohamed Belmedani

Abstract:

Energy source is a sustainable, totally inexhaustible and environmentally friendly alternative to the fossil fuels available. It is a renewable and economical energy that can be harnessed sustainably over the long term and thus stabilizes energy costs. Solar cooling technologies have been developed to decrease the augmentation electricity consumption for air conditioning and to displace the peak load during hot summer days. A numerical analysis of thermal and solar performances of an annular finned adsorber, which is the most important component of the adsorption solar refrigerating system, is considered in this work. Different adsorbent/adsorbate pairs, such as activated carbon AC35/methanol, activated carbon AC35/ethanol, and activated carbon BPL/Ammoniac, are undertaken in this study. The modeling of the adsorption cooling machine requires the resolution of the equation describing the energy and mass transfer in the tubular finned adsorber. The Wilson and Dubinin- Astakhov models of the solid-adsorbate equilibrium are used to calculate the adsorbed quantity. The porous medium and the fins are contained in the annular space, and the adsorber is heated by solar energy. Effects of key parameters on the adsorbed quantity and on the thermal and solar performances are analysed and discussed. The AC35/methanol pair is the best pair compared to BPL/Ammoniac and AC35/ethanol pairs in terms of system performance. The system performances are sensitive to the fin geometry. For the considered data measured for clear type days of July 2023 in Algeria and Morocco, the performances of the cooling system are very significant in Algeria.

Keywords: activated carbon AC35-methanol pair, activated carbon AC35-ethanol pair, activated carbon BPL-ammoniac pair, annular finned adsorber, performance coefficients, numerical analysis, solar cooling system

Procedia PDF Downloads 55

Authors: Eric Lai, Sarah Lorger, David Eisinger, Richard Waugh

Abstract:

Introduction: Percutaneous embolization of varicoceles has shown similar outcomes to surgery. However, there are advantages of radiological intervention as patients are not exposed to general anaesthesia, experience a quicker recovery and face a lower risk of major complications. Radiological interventions are also preferable after a failed surgical approach. We evaluate clinical outcomes of percutaneous embolization at a tertiary hospital in Sydney, Australia. Methods: Retrospective case series without a control group from a single site (Royal Prince Alfred Hospital, Sydney, Australia). A data search was performed on the interventional radiology database with the word “varicocele” between February 2017 and March 2022. 62 patients were identified. Each patient file was reviewed and included in the study if they met the inclusion criteria. Results: A total of 56 patients were included. 6 patients were excluded as they did not receive intervention after the initial diagnostic venography. Technical success was 100%. Complications were seen in 3 patients (5.3%). The complications included post-procedural pain and fever, venous perforation with no clinical adverse outcome, and a mild allergic reaction to contrast. Recurrence occurred in 3 patients (5.6%), all of whom received a successful second procedure. DISCUSSION: This study demonstrates comparable rates of technical success, complication rate and recurrence to other studies in the literature. When compared to surgical outcomes, the results were also similar. The main limitation is multiple patients lack long-term follow-up beyond 1 year, resulting in potential underestimation of the recurrence rate. Conclusion: Percutaneous embolization of varicocele is a safe alternative to surgical intervention.

Keywords: varicocele, interventional radiology, urology, radiology

Procedia PDF Downloads 71

Authors: Kuan-Hao Tsui, Li-Te Lin, Chia-Jung Li

Abstract:

The combination of Y-27632 and Vitamin C significantly enhances the quality of aging germ cells by reducing reactive oxygen species (ROS) production, restoring mitochondrial membrane potential balance, and promoting mitochondrial fusion. The age-related decline in oocyte quality contributes to reduced fertility, increased aneuploidy, and diminished embryo quality, with mitochondrial dysfunction in both oocytes and granulosa cells being a key factor in this decline. Experiments on aging germ cells investigated the effects of the Y-27632 and Vitamin C combination. In vivo studies involved aged mice to assess oocyte maturation and ROS accumulation during culture. The assessment included mitochondrial activity, ROS levels, mitochondrial membrane potential, and mitochondrial dynamics. Cellular energy metabolism and ATP production were also measured. The combination treatment effectively addressed mitochondrial dysfunction and regulated cellular energy metabolism, promoting oxygen respiration and increasing ATP production. In aged mice, this supplement treatment enhanced in vitro oocyte maturation and prevented ROS accumulation in aging oocytes during culture. While these findings are promising, further research is needed to explore the long-term effects and potential side effects of the Y-27632 and Vitamin C combination. Additionally, translating these findings to human subjects requires careful consideration. Overall, the study suggests that the Y-27632 and Vitamin C combination could be a promising intervention to mitigate aging-related dysfunction in germ cells, potentially enhancing oocyte quality, particularly in the context of in vitro fertilization.

Keywords: ovarian aging, supplements, ROS, mitochondria

Procedia PDF Downloads 40