Search results for: limited location storytelling
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6331

Search results for: limited location storytelling

2491 Low-Cost Reusable Thermal Energy Storage Particle for Concentrating Solar Power

Authors: Kyu Bum Han, Eunjin Jeon, Kimberly Watts, Brenda Payan Medina

Abstract:

Gen3 Concentrating Solar Power (CSP) high-temperature thermal systems have the potential to lower the cost of a CSP system. When compared to the other systems (chloride salt blends and supercritical fluids), the particle transport system can avoid many of the issues associated with high fluid temperature systems at high temperature because of its ability to operate at ambient pressure with limited corrosion or thermal stability risk. Furthermore, identifying and demonstrating low-cost particles that have excellent optical properties and durability can significantly reduce the levelized cost of electricity (LCOE) of particle receivers. The currently available thermal transfer particle in the study and market is oxidized at about 700oC, which reduces its durability, generates particle loss by high friction loads, and causes the color change. To meet the CSP SunShot goal, the durability of particles must be improved by identifying particles that are less abrasive to other structural materials. Furthermore, the particles must be economically affordable and the solar absorptance of the particles must be increased while minimizing thermal emittance. We are studying a novel thermal transfer particle, which has low cost, high durability, and high solar absorptance at high temperatures. The particle minimizes thermal emittance and will be less abrasive to other structural materials. Additionally, the particle demonstrates reusability, which significantly lowers the LCOE. This study will contribute to two principal disciplines of energy science: materials synthesis and manufacturing. Developing this particle for thermal transfer will have a positive impact on the ceramic study and industry as well as the society.

Keywords: concentrating solar power, thermal energy storage, particle, reusability, economics

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2490 Social Movements of Central-Eastern Europe: Examining Trends of Cooperation and Antagonism by Using Big Data

Authors: Reka Zsuzsanna Mathe

Abstract:

The globalization and the Europeanization have significantly contributed to a change in the role of the nation-states. The global economic crisis, the climate changes, and the recent refugee crisis, are just a few among many challenges that cannot be effectively addressed by the traditional role of the nation-states. One of the main roles of the states is to solve collective action problems, however due to their changing roles; apparently this is getting more and more difficult. Depending on political culture, collective action problems are solved either through cooperation or conflict. The political culture of Central and Eastern European (CEE) countries is marked by low civic participation and by a weak civil society. In this type of culture collective action problems are likely to be induced through conflict, rather than the democratic process of dialogue and any type of social change is probably to be introduced by social movements. Several studies have been conducted on the social movements of the CEE countries, yet, it is still not clear if the most significant social movements of the region tend to choose rather the cooperative or the conflictual way as action strategy. This study differentiates between a national and a European action field, having different social orders. The actors of the two fields are the broadly understood civil society members, conceptualized as social movements. This research tries to answer the following questions: a) What are the norms that best characterize the CEE countries’ social order? b) What type of actors would prefer a change and in which areas? c) Is there a significant difference between the main actors active in the national versus the European field? The main hypotheses are that there are conflicting norms defining the national and the European action field, and there is a significant difference between the action strategies adopted by social movements acting in the two different fields. In mapping the social order, the study uses data provided by the European Social Survey. Big data of the Global Data on Events, Location and Tone (GDELT) database offers information regarding the main social movements and their preferred type of action. The unit of the analysis is the so called ‘Visegrad 4’ countries: Poland, Czech Republic, Slovakia and Hungary and the research uses data starting from 2005 (after the European accession of these four countries) until May, 2017. According to the data, the main hypotheses were confirmed.

Keywords: big data, Central and Eastern Europe, civil society, GDELT, social movements

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2489 In-Vitro Dextran Synthesis and Characterization of an Intracellular Glucosyltransferase from Leuconostoc Mesenteroides AA1

Authors: Afsheen Aman, Shah Ali Ul Qader

Abstract:

Dextransucrase [EC 2.4.1.5] is a glucosyltransferase that catalysis the biosynthesis of a natural biopolymer called dextran. It can catalyze the transfer of D-glucopyranosyl residues from sucrose to the main chain of dextran. This unique biopolymer has multiple applications in several industries and the key utilization of dextran lies on its molecular weight and the type of branching. Extracellular dextransucrase from Leuconostoc mesenteroides is most extensively studied and characterized. Limited data is available regarding cell-bound or intracellular dextransucrase and on the characterization of dextran produced by in-vitro reaction of intracellular dextransucrase. L. mesenteroides AA1 is reported to produce extracellular dextransucrase that catalyzes biosynthesis of a high molecular weight dextran with only α-(1→6) linkage. Current study deals with the characterization of an intracellular dextransucrase and in vitro biosynthesis of low molecular weight dextran from L. mesenteroides AA1. Intracellular dextransucrase was extracted from cytoplasm and purified to homogeneity for characterization. Kinetic constants, molecular weight and N-terminal sequence analysis of intracellular dextransucrase reveal unique variation with previously reported extracellular dextransucrase from the same strain. In vitro synthesized biopolymer was characterized using NMR spectroscopic techniques. Intracellular dextransucrase exhibited Vmax and Km values of 130.8 DSU ml-1 hr-1 and 221.3 mM, respectively. Optimum catalytic activity was detected at 35°C in 0.15 M citrate phosphate buffer (pH-5.5) in 05 minutes. Molecular mass of purified intracellular dextransucrase is approximately 220.0 kDa on SDS-PAGE. N-terminal sequence of the intracellular enzyme is: GLPGYFGVN that showed no homology with previously reported sequence for the extracellular dextransucrase. This intracellular dextransucrase is capable of in vitro synthesis of dextran under specific conditions. This intracellular dextransucrase is capable of in vitro synthesis of dextran under specific conditions and this biopolymer can be hydrolyzed into different molecular weight fractions for various applications.

Keywords: characterization, dextran, dextransucrase, leuconostoc mesenteroides

Procedia PDF Downloads 384
2488 Identification of Accumulated Hydrocarbon Based on Heat Propagation Analysis in Order to Develop Mature Field: Case Study in South Sumatra Basin, Indonesia

Authors: Kukuh Suprayogi, Muhamad Natsir, Olif Kurniawan, Hot Parulian, Bayu Fitriana, Fery Mustofa

Abstract:

The new approach by utilizing the heat propagation analysis carried out by studying and evaluating the effect of the presence of hydrocarbons to the flow of heat that goes from the bottom surface to surface. Heat propagation is determined by the thermal conductivity of rocks. The thermal conductivity of rock itself is a quantity that describes the ability of a rock to deliver heat. This quantity depends on the constituent rock lithology, large porosity, and pore fluid filler. The higher the thermal conductivity of a rock, the more easily the flow of heat passing through these rocks. With the same sense, the heat flow will more easily pass through the rock when the rock is filled with water than hydrocarbons, given the nature of the hydrocarbons having more insulator against heat. The main objective of this research is to try to make the model the heat propagation calculations in degrees Celsius from the subsurface to the surface which is then compared with the surface temperature is measured directly at the point of location. In calculating the propagation of heat, we need to first determine the thermal conductivity of rocks, where the rocks at the point calculation are not composed of homogeneous but consist of strata. Therefore, we need to determine the mineral constituent and porosity values of each stratum. As for the parameters of pore fluid filler, we assume that all the pores filled with water. Once we get a thermal conductivity value of each unit of the rock, then we begin to model the propagation of heat profile from the bottom to the surface. The initial value of the temperature that we use comes from the data bottom hole temperature (BHT) is obtained from drilling results. Results of calculations per depths the temperature is displayed in plotting temperature versus depth profiles that describe the propagation of heat from the bottom of the well to the surface, note that pore fluid is water. In the technical implementation, we can identify the magnitude of the effect of hydrocarbons in reducing the amount of heat that crept to the surface based on the calculation of propagation of heat at a certain point and compared with measurements of surface temperature at that point, assuming that the surface temperature measured is the temperature that comes from the asthenosphere. This publication proves that the accumulation of hydrocarbon can be identified by analysis of heat propagation profile which could be a method for identifying the presence of hydrocarbons.

Keywords: thermal conductivity, rock, pore fluid, heat propagation

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2487 Processes of Identity Construction for Generation 1.5 Students in Canada

Authors: Timothy Mossman

Abstract:

The number of adolescent children accompanying their immigrant parents to Canada has steadily increased since the 1990s. Much of the applied linguistics literature on these so-called ‘Generation 1.5’ youth has focused on their deficiencies as academic writers in US Rhetoric and Composition and ESL contexts in higher education and the stigma of ESL in US K-12 contexts. However, the literature on Generation 1.5 students and identity in Canadian higher education is limited. This qualitative study investigates the processes of identity construction of three Generation 1.5 students studying at a university in Metro Vancouver to find out what types of identities and representations of self and other they make relevant, the meanings they attribute to their identities, and what motivates them to construct these identities. The study analyzes the accounts and experiences of the participants in interviews, focus groups, and texts and as ‘culture-in-action,’ positing that they constructed identities as social categories associated with the languages and social practices of their countries of birth, in liminal spaces among a continuum between Canada and their countries of birth, and a spectrum of related cultural representations. Ideas and beliefs associated with broader ‘macro’ social structures in Canadian society related to language, culture, legitimacy, immigration, power, distinction, and racism were shown to be transcended in and through their representations of themselves and others. Data suggest that moving to Canada caused participants to experience discontinuities between their cultures, languages, and social practices, and in some cases a conflicting sense of self. The study brings implications for finding ways to understand the complexity of immigrant students, avoid reifying and generalizing about them, and not see them as stuck-in-between or lacking.

Keywords: culture-in-action, generation 1.5, identity, membership categorization analysis

Procedia PDF Downloads 142
2486 Key Success Factors and Enterprise Resource Planning Implementation in Higher Education Institutions: Multiple Case Studies of Jordanian Universities

Authors: Abdallah Abu Madi, Dongmei Cao, Alexeis Garcia-Perez, Qile He

Abstract:

The failure of Enterprise Resource Planning (ERP) implementation in higher education institutions (HEIs) worldwide is much higher in comparison to other sectors, such as banking or manufacturing, to our knowledge limited research has been conducted on this issue. To date, prior literature has identified some key success factors (KSFs) mostly either in the domain of information and system (IS) or in the industrial context. However, evidence of ERP implementation in the higher education sector has had little attention in the extant literature. Hence, this paper identifies and categories KSFs of ERP implementation in HEIs. Semi-structured face-to-face interviews were conducted with technicians and managers from three Jordanian HEIs. From these case studies, three new sector- and context-specific KSFs were identified and categorized according to two dimensions: organizational and technical. The first new KSF is the selection of the ERP system, which is an influential factor in the organizational dimension. Results show that an ERP solution that is suitable to one context may be disastrous in another. The second new KSF, which falls under the technical dimension, is the relationship between vendors and HEIs. This must be fair and impartial to enable successful decision-making and thus the achievement of pre-defined goals. Also within the technical dimension is the third factor: in-house maintenance. Once an appropriate system is selected and a strong relationship is established, the ERP system requires continuous maintenance for effective operation. HEIs should ensure that qualified IT support is in place and in-house to avoid excessive running expenses.

Keywords: Enterprise Resource Planning (ERP)implementation, key success factors, higher education institutions, Jordanian higher education

Procedia PDF Downloads 198
2485 A Geo DataBase to Investigate the Maximum Distance Error in Quality of Life Studies

Authors: Paolino Di Felice

Abstract:

The background and significance of this study come from papers already appeared in the literature which measured the impact of public services (e.g., hospitals, schools, ...) on the citizens’ needs satisfaction (one of the dimensions of QOL studies) by calculating the distance between the place where they live and the location on the territory of the services. Those studies assume that the citizens' dwelling coincides with the centroid of the polygon that expresses the boundary of the administrative district, within the city, they belong to. Such an assumption “introduces a maximum measurement error equal to the greatest distance between the centroid and the border of the administrative district.”. The case study, this abstract reports about, investigates the implications descending from the adoption of such an approach but at geographical scales greater than the urban one, namely at the three levels of nesting of the Italian administrative units: the (20) regions, the (110) provinces, and the 8,094 municipalities. To carry out this study, it needs to be decided: a) how to store the huge amount of (spatial and descriptive) input data and b) how to process them. The latter aspect involves: b.1) the design of algorithms to investigate the geometry of the boundary of the Italian administrative units; b.2) their coding in a programming language; b.3) their execution and, eventually, b.4) archiving the results in a permanent support. The IT solution we implemented is centered around a (PostgreSQL/PostGIS) Geo DataBase structured in terms of three tables that fit well to the hierarchy of nesting of the Italian administrative units: municipality(id, name, provinceId, istatCode, regionId, geometry) province(id, name, regionId, geometry) region(id, name, geometry). The adoption of the DBMS technology allows us to implement the steps "a)" and "b)" easily. In particular, step "b)" is simplified dramatically by calling spatial operators and spatial built-in User Defined Functions within SQL queries against the Geo DB. The major findings coming from our experiments can be summarized as follows. The approximation that, on the average, descends from assimilating the residence of the citizens with the centroid of the administrative unit of reference is of few kilometers (4.9) at the municipalities level, while it becomes conspicuous at the other two levels (28.9 and 36.1, respectively). Therefore, studies such as those mentioned above can be extended up to the municipal level without affecting the correctness of the interpretation of the results, but not further. The IT framework implemented to carry out the experiments can be replicated for studies referring to the territory of other countries all over the world.

Keywords: quality of life, distance measurement error, Italian administrative units, spatial database

Procedia PDF Downloads 364
2484 Physics-Informed Convolutional Neural Networks for Reservoir Simulation

Authors: Jiangxia Han, Liang Xue, Keda Chen

Abstract:

Despite the significant progress over the last decades in reservoir simulation using numerical discretization, meshing is complex. Moreover, the high degree of freedom of the space-time flow field makes the solution process very time-consuming. Therefore, we present Physics-Informed Convolutional Neural Networks(PICNN) as a hybrid scientific theory and data method for reservoir modeling. Besides labeled data, the model is driven by the scientific theories of the underlying problem, such as governing equations, boundary conditions, and initial conditions. PICNN integrates governing equations and boundary conditions into the network architecture in the form of a customized convolution kernel. The loss function is composed of data matching, initial conditions, and other measurable prior knowledge. By customizing the convolution kernel and minimizing the loss function, the neural network parameters not only fit the data but also honor the governing equation. The PICNN provides a methodology to model and history-match flow and transport problems in porous media. Numerical results demonstrate that the proposed PICNN can provide an accurate physical solution from a limited dataset. We show how this method can be applied in the context of a forward simulation for continuous problems. Furthermore, several complex scenarios are tested, including the existence of data noise, different work schedules, and different good patterns.

Keywords: convolutional neural networks, deep learning, flow and transport in porous media, physics-informed neural networks, reservoir simulation

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2483 The Moving and Special Ability Influence Player Preference in the Dual Protagonist Game

Authors: Shih-Chieh Liao, Jen-Ying Ma

Abstract:

Dual protagonists game always bring a unique experience compared to the other games. This research wants to discuss whether the dual protagonists have the moving ability and special ability or not; it will affect the preference of the players. This research will focus on the single-player dual protagonists game. After the observation, we found that when players control the dual protagonists, the moving ability and special ability are a great point defining the preference of players. When players control the character, which is lack of moving ability, they often feel impatient with the inconvenient mechanism and then reduce the will to play with the character or even the game. Furthermore, the special ability is also important in the situation that there is another character to compare with. When the character is too powerful, players tend not to use the weaker one. In addition, gender is a big deal in the games. It surprisingly controls the will of play occasionally. In view of these, this research makes a single-player dual protagonists game and the dual protagonists are limited to male and female. The experiment content detected with Electrodermal Activity (EDA) includes seven different situations. (1) male and females both have the moving ability and special ability. (2) male and female both have a special ability, but female does not have the moving ability. (3) male and females both have a special ability, but the male does not have the moving ability. (4) male and female both have the moving ability, but the male does not have special ability (5) male and female both have the moving ability, but female does not have a special ability (6) male-only has the moving ability and female-only has a special ability (7) male-only has a special ability and female only has the moving ability. The experiment will evaluate the emotional changes of the subjects in those situations. The result sorted by the significance of player preference is (6)>(4)>(1)>(2)>(5)>(3)>(7). The result demonstrates that players prefer females with special abilities or males with moving abilities. The game developer could design the ability of dual protagonists based on this research. Therefore, players may have a better experience.

Keywords: biofeedback, dual protagonists, emotional responses, psychology, user experience

Procedia PDF Downloads 179
2482 Fabrication of Drug-Loaded Halloysite Nanotubes Containing Sodium Alginate/Gelatin Composite Scaffolds

Authors: Masoumeh Haghbin Nazarpak, Hamidreza Tolabi, Aryan Ekhlasi

Abstract:

Bone defects are mentioned as one of the most challenging clinical conditions, affecting millions of people each year. A fracture, osteoporosis, tumor, or infection usually causes these defects. At present, autologous and allogeneic grafts are used to correct bone defects, but these grafts have some difficulties, such as limited access, infection, disease transmission, and immune rejection. Bone tissue engineering is considered a new strategy for repairing bone defects. However, problems with scaffolds’ design with unique structures limit their clinical applications. In addition, numerous in-vitro studies have been performed on the behavior of bone cells in two-dimensional environments. Still, cells grow in physiological situations in the human body in a three-dimensional environment. As a result, the controlled design of porous structures with high structural complexity and providing the necessary flexibility to meet specific needs in bone tissue repair is beneficial. For this purpose, a three-dimensional composite scaffold based on gelatin and sodium alginate hydrogels is used in this research. In addition, the antibacterial drug-loaded halloysite nanotubes were introduced into the hydrogel scaffold structure to provide a suitable substrate for controlled drug release. The presence of halloysite nanotubes improved hydrogel’s properties, while the drug eliminated infection and disease transmission. Finally, it can be acknowledged that the composite scaffold prepared in this study for bone tissue engineering seems promising.

Keywords: halloysite nanotubes, bone tissue engineering, composite scaffold, controlled drug release

Procedia PDF Downloads 56
2481 The Effect of Oil Pollution on Marine Microbial Populations in Israeli Coastal Waters

Authors: Yael Shai, Dror L. Angel, Dror Zurel, Peleg Astrahan, Maxim Rubin-Blum, Eyal Rahav

Abstract:

The high demand for oil and its by-products is symptomatic of the 21st century and occasionally leads to oil spills and pollution of coastal waters. Marine oil pollution may originate from a variety of sources -urban runoff, tanker cleaning, drilling activities, and oil spills. These events may release large amounts of highly toxic polycyclic aromatic hydrocarbons (PAHs) and other pollutants to coastal water, thereby threatening local marine life. Here, we investigated the effects of crude oil on the temporal dynamics of phytoplankton and heterotrophic bacteria in Israeli coastal waters. To this end, we added crude oil (500 µm thick layer, with and without additional nutrients; NO₃ and PO₄) to mesocosms (1m³ bags) containing oligotrophic surface coastal water collected near Haifa during summer and winter. Changes in phytoplankton biomass, activity and diversity were monitored daily for 5-6 days. Our results demonstrate that crude oil addition resulted in a pronounced decrease in phytoplankton biomass and production rates, while heterotrophic bacterial production increased significantly. Importantly, a few days post addition we found that the oil-degrading bacteria, Oleibacter sp. and Oleispira sp. appeared in the mesocosms and that the addition of nutrients (along with the crude oil) further increased this trend. This suggests that oil-degrading bacteria may be NO₃ and PO₄ limited in Israeli coastal waters. The results of this study should enable us to establish improved science-based environmental policy with respect to handling crude oil pollution in this region.

Keywords: heterotrophic bacteria, nutrients, mesocosm, oil pollution, oligotrophic, phytoplankton

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2480 A Sub-Conjunctiva Injection of Rosiglitazone for Anti-Fibrosis Treatment after Glaucoma Filtration Surgery

Authors: Yang Zhao, Feng Zhang, Xuanchu Duan

Abstract:

Trans-differentiation of human Tenon fibroblasts (HTFs) to myo-fibroblasts and fibrosis of episcleral tissue are the most common reasons for the failure of glaucoma filtration surgery, with limited treatment options like antimetabolites which always have side-effects such as leakage of filter bulb, infection, hypotony, and endophthalmitis. Rosiglitazone, a specific thiazolidinedione is a synthetic high-affinity ligand for PPAR-r, which has been used in the treatment of type2 diabetes, and found to have pleiotropic functions against inflammatory response, cell proliferation and tissue fibrosis and to benefit to a variety of diseases in animal myocardium models, steatohepatitis models, etc. Here, in vitro we cultured primary HTFs and stimulated with TGF- β to induced myofibrogenic, then treated cells with Rosiglitazone to assess for fibrogenic response. In vivo, we used rabbit glaucoma model to establish the formation of post- trabeculectomy scarring. Then we administered subconjunctival injection with Rosiglitazone beside the filtering bleb, later protein, mRNA and immunofluorescence of fibrogenic markers are checked, and filtering bleb condition was measured. In vitro, we found Rosiglitazone could suppressed proliferation and migration of fibroblasts through macroautophagy via TGF- β /Smad signaling pathway. In vivo, on postoperative day 28, the mean number of fibroblasts in Rosiglitazone injection group was significantly the lowest and had the least collagen content and connective tissue growth factor. Rosiglitazone effectively controlled human and rabbit fibroblasts in vivo and in vitro. Its subconjunctiiva application may represent an effective, new avenue for the prevention of scarring after glaucoma surgery.

Keywords: fibrosis, glaucoma, macroautophagy, rosiglitazone

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2479 On the Existence of Homotopic Mapping Between Knowledge Graphs and Graph Embeddings

Authors: Jude K. Safo

Abstract:

Knowledge Graphs KG) and their relation to Graph Embeddings (GE) represent a unique data structure in the landscape of machine learning (relative to image, text and acoustic data). Unlike the latter, GEs are the only data structure sufficient for representing hierarchically dense, semantic information needed for use-cases like supply chain data and protein folding where the search space exceeds the limits traditional search methods (e.g. page-rank, Dijkstra, etc.). While GEs are effective for compressing low rank tensor data, at scale, they begin to introduce a new problem of ’data retreival’ which we observe in Large Language Models. Notable attempts by transE, TransR and other prominent industry standards have shown a peak performance just north of 57% on WN18 and FB15K benchmarks, insufficient practical industry applications. They’re also limited, in scope, to next node/link predictions. Traditional linear methods like Tucker, CP, PARAFAC and CANDECOMP quickly hit memory limits on tensors exceeding 6.4 million nodes. This paper outlines a topological framework for linear mapping between concepts in KG space and GE space that preserve cardinality. Most importantly we introduce a traceable framework for composing dense linguistic strcutures. We demonstrate performance on WN18 benchmark this model hits. This model does not rely on Large Langauge Models (LLM) though the applications are certainy relevant here as well.

Keywords: representation theory, large language models, graph embeddings, applied algebraic topology, applied knot theory, combinatorics

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2478 Mapping Soils from Terrain Features: The Case of Nech SAR National Park of Ethiopia

Authors: Shetie Gatew

Abstract:

Current soil maps of Ethiopia do not represent accurately the soils of Nech Sar National Park. In the framework of studies on the ecology of the park, we prepared a soil map based on field observations and a digital terrain model derived from SRTM data with a 30-m resolution. The landscape comprises volcanic cones, lava and basalt outflows, undulating plains, horsts, alluvial plains and river deltas. SOTER-like terrain mapping units were identified. First, the DTM was classified into 128 terrain classes defined by slope gradient (4 classes), relief intensity (4 classes), potential drainage density (2 classes), and hypsometry (4 classes). A soil-landscape relation between the terrain mapping units and WRB soil units was established based on 34 soil profile pits. Based on this relation, the terrain mapping units were either merged or split to represent a comprehensive soil and terrain map. The soil map indicates that Leptosols (30 %), Cambisols (26%), Andosols (21%), Fluvisols (12 %), and Vertisols (9%) are the most widespread Reference Soil Groups of the park. In contrast, the harmonized soil map of Africa derived from the FAO soil map of the world indicates that Luvisols (70%), Vertisols (14%) and Fluvisols (16%) would be the most common Reference Soil Groups. However, these latter mapping units are not consistent with the topography, nor did we find such extensive areas occupied by Luvisols during the field survey. This case study shows that with the now freely available SRTM data, it is possible to improve current soil information layers with relatively limited resources, even in a complex terrain like Nech Sar National Park.

Keywords: andosols, cambisols, digital elevation model, leptosols, soil-landscaps relation

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2477 Validity of Clinical Disease Activity Index (CDAI) to Evaluate the Disease Activity of Rheumatoid Arthritis Patients in Sri Lanka: A Prospective Follow up Study Based on Newly Diagnosed Patients

Authors: Keerthie Dissanayake, Chandrika Jayasinghe, Priyani Wanigasekara, Jayampathy Dissanayake, Ajith Sominanda

Abstract:

The routine use of Disease Activity Score-28 (DAS28) to assess the disease activity in rheumatoid arthritis (RA) is limited due to its dependency on laboratory investigations and the complex calculations involved. In contrast, the clinical disease activity index (CDAI) is simple to calculate, which makes the "treat to target" strategy for the management of RA more practical. We aimed to assess the validity of CDAI compared to DAS28 in RA patients in Sri Lanka. A total of 103 newly diagnosed RA patients were recruited, and their disease activity was calculated using DAS 28 and CDAI during the first visit to the clinic (0 months) and re-assessed at 4 and 9 months of the follow-up visits. The validity of the CDAI, compared to DAS 28, was evaluated. Patients had a female preponderance (6:1) and a short symptom duration (mean = 6.33 months). The construct validity of CDAI, as assessed by Cronbach's α test, was 0.868. Convergent validity was assessed by correlation and Kappa statistics. Strong positive correlations were observed between CDAI and DAS 28 at the baseline (0 months), 4, and 9 months of evaluation (Spearman's r = 0.9357, 0.9354, 0.9106, respectively). Moderate-good inter-rater agreements between the DAS-28 and CDAI were observed (Weighted kappa of 0.660, 0.519, and 0.741 at 0, 4, and 9 months respectively). Discriminant validity, as assessed by ROC curves at 0, 4th, and 9th months of the evaluation, showed the area under the curve (AUC) of 0.958, 0.985, and 0.914, respectively. The suggested cut-off points for different CDAI disease activity categories according to ROC curves were ≤ 2 (Remission), >2 to ≤ 5 (low), >5 to ≤ 18 (moderate), > 18 (high). These findings indicate that the CDAI has good concordance with DAS 28 in assessing the disease activity in RA patients in this study sample.

Keywords: rheumatoid arthritis, CDAI, disease activity, Sri Lanka, validation

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2476 Understanding Retail Benefits Trade-offs of Dynamic Expiration Dates (DED) Associated with Food Waste

Authors: Junzhang Wu, Yifeng Zou, Alessandro Manzardo, Antonio Scipioni

Abstract:

Dynamic expiration dates (DEDs) play an essential role in reducing food waste in the context of the sustainable cold chain and food system. However, it is unknown for the trades-off in retail benefits when setting an expiration date on fresh food products. This study aims to develop a multi-dimensional decision-making model that integrates DEDs with food waste based on wireless sensor network technology. The model considers the initial quality of fresh food and the change rate of food quality with the storage temperature as cross-independent variables to identify the potential impacts of food waste in retail by applying s DEDs system. The results show that retail benefits from the DEDs system depend on each scenario despite its advanced technology. In the DEDs, the storage temperature of the retail shelf leads to the food waste rate, followed by the change rate of food quality and the initial quality of food products. We found that the DEDs system could reduce food waste when food products are stored at lower temperature areas. Besides, the potential of food savings in an extended replenishment cycle is significantly more advantageous than the fixed expiration dates (FEDs). On the other hand, the information-sharing approach of the DEDs system is relatively limited in improving sustainable assessment performance of food waste in retail and even misleads consumers’ choices. The research provides a comprehensive understanding to support the techno-economic choice of the DEDs associated with food waste in retail.

Keywords: dynamic expiry dates (DEDs), food waste, retail benefits, fixed expiration dates (FEDs)

Procedia PDF Downloads 102
2475 Flood Devastation Assessment Through Mapping in Nigeria-2022 using Geospatial Techniques

Authors: Hafiz Muhammad Tayyab Bhatti, Munazza Usmani

Abstract:

One of nature's most destructive occurrences, floods do immense damage to communities and economic losses. Nigeria country, specifically southern Nigeria, is known for being prone to flooding. Even though periodic flooding occurs in Nigeria frequently, the floods of 2022 were the worst since those in 2012. Flood vulnerability analysis and mapping are still lacking in this region due to the very limited historical hydrological measurements and surveys on the effects of floods, which makes it difficult to develop and put into practice efficient flood protection measures. Remote sensing and Geographic Information Systems (GIS) are useful approaches to detecting, determining, and estimating the flood extent and its impacts. In this study, NOAA VIIR has been used to extract the flood extent using the flood water fraction data and afterward fused with GIS data for some zonal statistical analysis. The estimated possible flooding areas are validated using satellite imagery from the Moderate Resolution Imaging Spectroradiometer (MODIS). The goal is to map and studied flood extent, flood hazards, and their effects on the population, schools, and health facilities for each state of Nigeria. The resulting flood hazard maps show areas with high-risk levels clearly and serve as an important reference for planning and implementing future flood mitigation and control strategies. Overall, the study demonstrated the viability of using the chosen GIS and remote sensing approaches to detect possible risk regions to secure local populations and enhance disaster response capabilities during natural disasters.

Keywords: flood hazards, remote sensing, damage assessment, GIS, geospatial analysis

Procedia PDF Downloads 115
2474 Effects of a Head Mounted Display Adaptation on Reaching Behaviour: Implications for a Therapeutic Approach in Unilateral Neglect

Authors: Taku Numao, Kazu Amimoto, Tomoko Shimada, Kyohei Ichikawa

Abstract:

Background: Unilateral spatial neglect (USN) is a common syndrome following damage to one hemisphere of the brain (usually the right side), in which a patient fails to report or respond to stimulation from the contralesional side. These symptoms are not due to primary sensory or motor deficits, but instead, reflect an inability to process input from that side of their environment. Prism adaptation (PA) is a therapeutic treatment for USN, wherein a patient’s visual field is artificially shifted laterally, resulting in a sensory-motor adaptation. However, patients with USN also tend to perceive a left-leaning subjective vertical in the frontal plane. The traditional PA cannot be used to correct a tilt in the subjective vertical, because a prism can only polarize, not twist, the surroundings. However, this can be accomplished using a head mounted display (HMD) and a web-camera. Therefore, this study investigated whether an HMD system could be used to correct the spatial perception of USN patients in the frontal as well as the horizontal plane. We recruited healthy subjects in order to collect data for the refinement of USN patient therapy. Methods: Eight healthy subjects sat on a chair wearing a HMD (Oculus rift DK2), with a web-camera (Ovrvision) displaying a 10 degree leftward rotation and a 10 degree counter-clockwise rotation along the frontal plane. Subjects attempted to point a finger at one of four targets, assigned randomly, a total of 48 times. Before and after the intervention, each subject’s body-centre judgment (BCJ) was tested by asking them to point a finger at a touch panel straight in front of their xiphisternum, 10 times sight unseen. Results: Intervention caused the location pointed to during the BCJ to shift 35 ± 17 mm (Ave ± SD) leftward in the horizontal plane, and 46 ± 29 mm downward in the frontal plane. The results in both planes were significant by paired-t-test (p<.01). Conclusions: The results in the horizontal plane are consistent with those observed following PA. Furthermore, the HMD and web-camera were able to elicit 3D effects, including in both the horizontal and frontal planes. Future work will focus on applying this method to patients with and without USN, and investigating whether subject posture is also affected by the HMD system.

Keywords: head mounted display, posture, prism adaptation, unilateral spatial neglect

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2473 Environmental Analysis of Urban Communities: A Case Study of Air Pollutant Distribution in Smouha Arteries, Alexandria Egypt

Authors: Sammar Zain Allam

Abstract:

Smart Growth, intelligent cities, and healthy cities cited by WHO world health organization; they all call for clean air and minimizing air pollutants considering human health. Air quality is a thriving matter to achieve ecological cities; towards sustainable environmental development of urban fabric design. Selection criteria depends on the strategic location of our area as it is located at the entry of the city of Alexandria from its agricultural road. Besides, it represents the city center for retail, business, and educational amenities. Our study is analyzing readings of definite factors affecting air quality in a centric area in Alexandria. Our readings will be compared to standard measures of carbon dioxide, carbon monoxide, suspended particles, and air velocity or air flow. Carbon emissions are pondered in our study, in addition to suspended particles and the air velocity or air flow. Carbon dioxide and carbon monoxide crystalize the main elements to necessitate environmental and sustainable studies with the appearance of global warming and the glass house effect. Nevertheless, particulate matters are increasing causing breath issues especially to children and elder people; still threatening future generations to meet their own needs; sustainable development definition. Analysis of carbon dioxide, carbon monoxide, suspended particles together with air velocity or air flow has taken place in our area of study to manifest the relationship between these elements and the urban fabric design and land use distribution. For conclusion, dense urban fabric affecting air flow, and thus result in the concentration of air pollutants in certain zones. The appearance of open space with green areas allow the fading of air pollutants and help in their absorption. Along with dense urban fabric, high rise buildings trap air carriers which contribute to high readings of our elements. Also, street design may facilitate the circulation of air which helps carrying these pollutant away and distribute it to a wider space which decreases its harms and effects.

Keywords: carbon emissions, air quality measurements, arteries air quality, airflow or air velocity, particulate matter, clean air, urban density

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2472 Omni-Modeler: Dynamic Learning for Pedestrian Redetection

Authors: Michael Karnes, Alper Yilmaz

Abstract:

This paper presents the application of the omni-modeler towards pedestrian redetection. The pedestrian redetection task creates several challenges when applying deep neural networks (DNN) due to the variety of pedestrian appearance with camera position, the variety of environmental conditions, and the specificity required to recognize one pedestrian from another. DNNs require significant training sets and are not easily adapted for changes in class appearances or changes in the set of classes held in its knowledge domain. Pedestrian redetection requires an algorithm that can actively manage its knowledge domain as individuals move in and out of the scene, as well as learn individual appearances from a few frames of a video. The Omni-Modeler is a dynamically learning few-shot visual recognition algorithm developed for tasks with limited training data availability. The Omni-Modeler adapts the knowledge domain of pre-trained deep neural networks to novel concepts with a calculated localized language encoder. The Omni-Modeler knowledge domain is generated by creating a dynamic dictionary of concept definitions, which are directly updatable as new information becomes available. Query images are identified through nearest neighbor comparison to the learned object definitions. The study presented in this paper evaluates its performance in re-identifying individuals as they move through a scene in both single-camera and multi-camera tracking applications. The results demonstrate that the Omni-Modeler shows potential for across-camera view pedestrian redetection and is highly effective for single-camera redetection with a 93% accuracy across 30 individuals using 64 example images for each individual.

Keywords: dynamic learning, few-shot learning, pedestrian redetection, visual recognition

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2471 Demonstration of Logical Inconsistency in the Discussion of the Problem of Evil

Authors: Mohammad Soltani Renani

Abstract:

The problem of evil is one of the heated battlegrounds of the idea of theism and its critics. Since time immemorial and in various philosophical schools and religions, the belief in an Omniscient, Omnipotent, and Absolutely Good God has been considered inconsistent with the existence of the evil in the universe. The theist thinkers have generally adopted one of the following four ways for answering this problem: denial of the existence of evil or considering it to be relative, privation theory of evil, attribution of evil to something other than God, and depiction of an alternative picture of God. Defense or criticism of these alternative answers have given rise to an extensive and unending dispute. However, evaluation of the presupposition and context upon/in which a question is raised precedes offering an answer to it. This point in the discussion of the problem of evil is of paramount importance for both parties, i.e., questioners and answerers, that the attributes of knowledge, power, love, good-will, among others, can be supposed to be infinite only in the essence of the attributed and the domain of potentiality but what can be realized in the domain of actuality is always finite. Therefore, infinite nature of Divine Attributes and realization of evil belong to two spheres. Divine Attributes are infinite (absolute) in Divine Essence, but when they are created, each one becomes bounded by the other. This boundedness is a result of the state of being surrounded of the attributes by each other in finite world of possibility. Evil also appears in this limited world. This inconsistency leads to the collapse of the problem of evil from within: the place of infinity of the Divine Attributes, in the words of Muslim mystics, lies in the Holiest Manifestation [Feyze Aqdas] while evil emerges in the Holy Manifestation where the Divine Attributes become bounded by each other. This idea is neither a new answer to the problem of evil nor a defense of theism; rather it reveals a logical inconsistency in the discussion of the problem of evil.

Keywords: problem of evil, infinity of divine attributes, boundedness of divine attributes, holiest manifestation, holy manifestation

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2470 Evaluating the Satisfaction of Chinese Consumers toward Influencers at TikTok

Authors: Noriyuki Suyama

Abstract:

The progress and spread of digitalization have led to the provision of a variety of new services. The recent progress in digitization can be attributed to rapid developments in science and technology. First, the research and diffusion of artificial intelligence (AI) has made dramatic progress. Around 2000, the third wave of AI research, which had been underway for about 50 years, arrived. Specifically, machine learning and deep learning were made possible in AI, and the ability of AI to acquire knowledge, define the knowledge, and update its own knowledge in a quantitative manner made the use of big data practical even for commercial PCs. On the other hand, with the spread of social media, information exchange has become more common in our daily lives, and the lending and borrowing of goods and services, in other words, the sharing economy, has become widespread. The scope of this trend is not limited to any industry, and its momentum is growing as the SDGs take root. In addition, the Social Network Service (SNS), a part of social media, has brought about the evolution of the retail business. In the past few years, social network services (SNS) involving users or companies have especially flourished. The People's Republic of China (hereinafter referred to as "China") is a country that is stimulating enormous consumption through its own unique SNS, which is different from the SNS used in developed countries around the world. This paper focuses on the effectiveness and challenges of influencer marketing by focusing on the influence of influencers on users' behavior and satisfaction with Chinese SNSs. Specifically, Conducted was the quantitative survey of Tik Tok users living in China, with the aim of gaining new insights from the analysis and discussions. As a result, we found several important findings and knowledge.

Keywords: customer satisfaction, social networking services, influencer marketing, Chinese consumers’ behavior

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2469 Modelling and Simulating CO2 Electro-Reduction to Formic Acid Using Microfluidic Electrolytic Cells: The Influence of Bi-Sn Catalyst and 1-Ethyl-3-Methyl Imidazolium Tetra-Fluoroborate Electrolyte on Cell Performance

Authors: Akan C. Offong, E. J. Anthony, Vasilije Manovic

Abstract:

A modified steady-state numerical model is developed for the electrochemical reduction of CO2 to formic acid. The numerical model achieves a CD (current density) (~60 mA/cm2), FE-faradaic efficiency (~98%) and conversion (~80%) for CO2 electro-reduction to formic acid in a microfluidic cell. The model integrates charge and species transport, mass conservation, and momentum with electrochemistry. Specifically, the influences of Bi-Sn based nanoparticle catalyst (on the cathode surface) at different mole fractions and 1-ethyl-3-methyl imidazolium tetra-fluoroborate ([EMIM][BF4]) electrolyte, on CD, FE and CO2 conversion to formic acid is studied. The reaction is carried out at a constant concentration of electrolyte (85% v/v., [EMIM][BF4]). Based on the mass transfer characteristics analysis (concentration contours), mole ratio 0.5:0.5 Bi-Sn catalyst displays the highest CO2 mole consumption in the cathode gas channel. After validating with experimental data (polarisation curves) from literature, extensive simulations reveal performance measure: CD, FE and CO2 conversion. Increasing the negative cathode potential increases the current densities for both formic acid and H2 formations. However, H2 formations are minimal as a result of insufficient hydrogen ions in the ionic liquid electrolyte. Moreover, the limited hydrogen ions have a negative effect on formic acid CD. As CO2 flow rate increases, CD, FE and CO2 conversion increases.

Keywords: carbon dioxide, electro-chemical reduction, ionic liquids, microfluidics, modelling

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2468 Review of Sulfur Unit Capacity Expansion Options

Authors: Avinashkumar Karre

Abstract:

Sulfur recovery unit, most commonly called as Claus process, is very significant gas desulfurization process unit in refinery and gas industries. Explorations of new natural gas fields, refining of high-sulfur crude oils, and recent crude expansion projects are needing capacity expansion of Claus unit for many companies around the world. In refineries, the sulphur recovery units take acid gas from amine regeneration units and sour water strippers, converting hydrogen sulfide to elemental sulfur using the Claus process. The Claus process is hydraulically limited by mass flow rate. Reducing the pressure drop across control valves, flow meters, lines, knock-out drums, and packing improves the capacity. Oxygen enrichment helps improve the capacity by removing nitrogen, this is more commonly done on all capacity expansion projects. Typical upgrades required due to oxygen enrichment are new burners, new refractory in thermal reactor, resizing of 1st condenser, instrumentation changes, and steam/condensate heat integration. Some other capacity expansion options typically considered are tail gas compressor, replacing air blower with higher head, hydrocarbon minimization in the feed, water removal, and ammonia removal. Increased capacity related upgrades in sulfur recovery unit also need changes in the tail gas treatment unit, typical changes include improvement to quench tower duty, packing area upgrades in quench and absorber towers and increased amine circulation flow rates.

Keywords: Claus process, oxygen enrichment, sulfur recovery unit, tail gas treatment unit

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2467 Challenging Heteronormativity and Mononormativity in Academia: Incorporating Consensual Non-Monogamy into Psychological Romantic Relationship Research

Authors: Jessica Wood, Serge Desmarais

Abstract:

There has been recent resurgence in the popular and academic interest of consensual non-monogamous (CNM) relationships- an umbrella term that defines relationships in which each partner has openly agreed to engage in additional romantic and/or sexual relationships outside of their primary partnership. Despite an increase in the academic study of CNM, little psychological attention has been paid to the study of CNM, with the consideration of these relationships commonly occurring within related social science disciplines such as sociology or anthropology. As a discipline, psychology has a history of conducting research in the area of intimate relationships, and psychologists have amassed a wealth of theoretical knowledge in this field. However, historically individuals who engage in "alternative" sexual and romantic behaviours, such as non-heterosexual sex or sex with multiple partners have been pathologized within psychological research. Individuals in CNM relationships or individuals identifying as lesbian, gay, bisexual, trans or queer have often been excluded from research or “othered” in psychological interpretations of what healthy relationships entail. Thus, our current theoretical understandings of romantic relationships are limited to heterosexual, monogamous relationships. The goal of this presentation is to examine commonly cited components of relationship satisfaction (e.g., commitment, communication) and to critically assess how CNM experiences are presented in, or missing from, the psychological literature on romantic relationships. Additionally, the presentation will also consider how CNM relationships may add to our understanding or enhancement of traditional psychological theories and address issues related to heteronormativity and mononormativity within the discipline. Finally, we will close with a consideration of additional theoretical perspectives that may aid in our understanding of CNM relationships and suggest directions for future research.

Keywords: heteronormativity, mononormativity, psychological research, diverse relationships, gender, sexuality, feminism, queer theory

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2466 Integrating Knowledge Distillation of Multiple Strategies

Authors: Min Jindong, Wang Mingxia

Abstract:

With the widespread use of artificial intelligence in life, computer vision, especially deep convolutional neural network models, has developed rapidly. With the increase of the complexity of the real visual target detection task and the improvement of the recognition accuracy, the target detection network model is also very large. The huge deep neural network model is not conducive to deployment on edge devices with limited resources, and the timeliness of network model inference is poor. In this paper, knowledge distillation is used to compress the huge and complex deep neural network model, and the knowledge contained in the complex network model is comprehensively transferred to another lightweight network model. Different from traditional knowledge distillation methods, we propose a novel knowledge distillation that incorporates multi-faceted features, called M-KD. In this paper, when training and optimizing the deep neural network model for target detection, the knowledge of the soft target output of the teacher network in knowledge distillation, the relationship between the layers of the teacher network and the feature attention map of the hidden layer of the teacher network are transferred to the student network as all knowledge. in the model. At the same time, we also introduce an intermediate transition layer, that is, an intermediate guidance layer, between the teacher network and the student network to make up for the huge difference between the teacher network and the student network. Finally, this paper adds an exploration module to the traditional knowledge distillation teacher-student network model. The student network model not only inherits the knowledge of the teacher network but also explores some new knowledge and characteristics. Comprehensive experiments in this paper using different distillation parameter configurations across multiple datasets and convolutional neural network models demonstrate that our proposed new network model achieves substantial improvements in speed and accuracy performance.

Keywords: object detection, knowledge distillation, convolutional network, model compression

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2465 Self-Management among the Ethnic Groups with Type 2 Diabetes Mellitus in Thailand

Authors: Siwarak Kitchanapaibul, Warren Gillibrand, Rob Burton

Abstract:

The prevalence of diabetes mellitus has been rising all over the world. Self-management is required for diabetes mellitus patients. The objective of this study is to explore the self-management among the ethnic groups with type 2 diabetes mellitus in Thailand, an upper middle-income country which is located in South East Asia. The ethnic groups in Thailand are a minority group which has limited education and a different culture, language, costume and lifestyle from Thai people. The qualitative exploratory study was used in this study. In-depth interviews with semi-structured open questions were conducted by 20 participants from purposive sampling. These participants were the ethnic groups who have type 2 diabetes mellitus, received the services from a region hospital, understood Thai and were willing to participate. Content analysis was adopted for the study. The results showed that all of the participants controlled their diet before the appointment day and never miss their appointment. Only 3 participants did their exercise while 2 participants stated that they occasionally forgot to take medicine. 10 participants use the herbs for reducing the sugar level. 12 participants drank a lot of water after a lapse in the diet because they believed that water could dilute the sugar. The findings identified 5 themes; ‘controlling diet before appointment day’; ‘drinking water after a lapse in diet’; ‘medication being a vital importance’; ‘exercise is unimportant’; and ‘taking herbs for sugar reduction’. The results of this study are important to the health professionals to understand the self-management of Ethnic groups and use the data to create the appropriate intervention for promoting health among the ethnic groups with type 2 diabetes mellitus in Thailand. The findings will lead to the revision of health policy and the procedure for promoting health in this special ethnic groups.

Keywords: self-management, diabetes, ethnic groups, Thailand

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2464 The Impact of Preference-Based Employee Deployment toward Employee Satisfaction and Organizational Performance: Case Study in Directorate General of State Asset Management, Ministry of Finance of the Republic of Indonesia

Authors: Rahmat Irawan, Mundhir Hanifsyam Harahap, Andar Ristabet Hesda

Abstract:

As a public sector organization in Indonesia, Directorate General of State Asset Management (DGSAM) which is a unit under the Ministry of Finance of The Republic of Indonesia, has many constraints in managing its employees. While private organizations are able to conduct a human resource management as the best practice, DGSAM is limited by many regulations, especially about punishment and lay off policy for under-performance employees. Therefore, since 2015, DGSAM tries to implement a new and uncommon approach considering employees’ preference to encourage the motivation and performance of employees. DGSAM’s employees may propose the job places, and DGSAM considers them in deciding employees deployment. This study tries to determine the impact of preference-based approach toward employees’ satisfaction and organizational performance. This study uses quantitative approaches by regression analysis to measure the impact of deployment toward satisfaction of deployed employees and performance change of related units in DGSAM. The result of this study shows that preference-based approach significantly improves employees’ satisfaction and performance of related units as well. Based on the results of this study, it can be suggested that the approach is able to be implemented in the wider scope of the Ministry of Finance of The Republic of Indonesia and whole public sector organization in Indonesia. However, this study only focuses on short term measurement, so it is suggested to do further study to analyze the long-term impact.

Keywords: employee deployment, employee satisfaction, human resource management, organizational performance, preference-based approach

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2463 Decoding Wallstreetbets: Daily Disagreements Among Retail Investors Echo in Trading Volumes

Authors: Farzaneh Ghandehari, Helen Lu, Lina El-Jahel, Dulani Jayasuriya

Abstract:

Disagreement among investors is a fundamental aspect of financial markets, significantly influencing market dynamics. Previous research highlights the challenges of effectively measuring investor disagreement, often relying on traditional proxies like analyst forecast dispersion, which are limited by biases and infrequent updates. Recent movements in social media indicate that retail investors actively seek financial advice online and can influence the stock market. The evolution of the investing landscape, particularly the rise of social media as a hub for financial advice, provides a novel avenue for real-time measurement of investor sentiment and disagreement. Platforms like Reddit offer rich, community-driven discussions that reflect genuine investor opinions. This research explores how social media empowers retail investors and the potential of leveraging textual analysis of social media content to capture daily fluctuations in investor disagreement. This study investigates the relationship between daily investor disagreement and trading volume, focusing on the role of social media platforms in shaping market dynamics, specifically using data from WallStreetBets (WSB) on Reddit. This paper uses data from 2020 to 2023 from WSB and analyses 4,896 firms with enough social media activity in WSB to define stock-day level disagreement measures. Consistent with traditional theories that disagreement induces trading volume, the results show significant evidence supporting this claim through different disagreement measures derived from WSB discussions.

Keywords: retail investor, social media, disagreement, social finance, reddit, fintech

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2462 Modified Clusterwise Regression for Pavement Management

Authors: Mukesh Khadka, Alexander Paz, Hanns de la Fuente-Mella

Abstract:

Typically, pavement performance models are developed in two steps: (i) pavement segments with similar characteristics are grouped together to form a cluster, and (ii) the corresponding performance models are developed using statistical techniques. A challenge is to select the characteristics that define clusters and the segments associated with them. If inappropriate characteristics are used, clusters may include homogeneous segments with different performance behavior or heterogeneous segments with similar performance behavior. Prediction accuracy of performance models can be improved by grouping the pavement segments into more uniform clusters by including both characteristics and a performance measure. This grouping is not always possible due to limited information. It is impractical to include all the potential significant factors because some of them are potentially unobserved or difficult to measure. Historical performance of pavement segments could be used as a proxy to incorporate the effect of the missing potential significant factors in clustering process. The current state-of-the-art proposes Clusterwise Linear Regression (CLR) to determine the pavement clusters and the associated performance models simultaneously. CLR incorporates the effect of significant factors as well as a performance measure. In this study, a mathematical program was formulated for CLR models including multiple explanatory variables. Pavement data collected recently over the entire state of Nevada were used. International Roughness Index (IRI) was used as a pavement performance measure because it serves as a unified standard that is widely accepted for evaluating pavement performance, especially in terms of riding quality. Results illustrate the advantage of the using CLR. Previous studies have used CLR along with experimental data. This study uses actual field data collected across a variety of environmental, traffic, design, and construction and maintenance conditions.

Keywords: clusterwise regression, pavement management system, performance model, optimization

Procedia PDF Downloads 239