Search results for: dynamic function
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8502

Search results for: dynamic function

2112 Experimental Investigation of Mechanical Friction Influence in Semi-Hydraulic Clutch Actuation System Over Mileage

Authors: Abdul Azarrudin M. A., Pothiraj K., Kandasamy Satish

Abstract:

In the current automobile scenario, there comes a demand on more sophistication and comfort drive feel on passenger segments. The clutch pedal effort is one such customer touch feels in manual transmission vehicles, where the driver continuous to operate the clutch pedal in his entire the driving maneuvers. Hence optimum pedal efforts at green condition and over mileage to be ensured for fatigue free the driving. As friction is one the predominant factor and its tendency to challenge the technicality by causing the function degradation. One such semi-hydraulic systems shows load efficiency of about 70-75% over lifetime only due to the increase in friction which leads to the increase in pedal effort and cause fatigue to the vehicle driver. This work deals with the study of friction with different interfaces and its influence in the fulcrum points over mileage, with the objective of understanding the trend over mileage and determining the alternative ways of resolving it. In that one way of methodology is the reduction of friction by experimental investigation of various friction reduction interfaces like metal-to-metal interface and it has been tried out and is detailed further. Also, the specific attention has been put up considering the fulcrum load and its contact interfaces to move on with this study. The main results of the experimental data with the influence of three different contact interfaces are being presented with an ultimate intention of ending up into less fatigue with longer consistent pedal effort, thus smoothens the operation of the end user. The Experimental validation also has been done through rig-level test setup to depict the performance at static condition and in-parallel vehicle level test has also been performed to record the additional influences if any.

Keywords: automobile, clutch, friction, fork

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2111 Biophysical Characterization of Archaeal Cyclophilin Like Chaperone Protein

Authors: Vineeta Kaushik, Manisha Goel

Abstract:

Chaperones are proteins that help other proteins fold correctly, and are found in all domains of life i.e., prokaryotes, eukaryotes and archaea. Various comparative genomic studies have suggested that the archaeal protein folding machinery appears to be highly similar to that found in eukaryotes. In case of protein folding; slow rotation of peptide prolyl-imide bond is often the rate limiting step. Formation of the prolyl-imide bond during the folding of a protein requires the assistance of other proteins, termed as peptide prolyl cis-trans isomerases (PPIases). Cyclophilins constitute the class of peptide prolyl isomerases with a wide range of biological function like protein folding, signaling and chaperoning. Most of the cyclophilins exhibit PPIase enzymatic activity and play active role in substrate protein folding which classifies them as a category of molecular chaperones. Till date, there is not very much data available in the literature on archaeal cyclophilins. We aim to compare the structural and biochemical features of the cyclophilin protein from within the three domains to elucidate the features affecting their stability and enzyme activity. In the present study, we carry out in-silico analysis of the cyclophilin proteins to predict their conserved residues, sites under positive selection and compare these proteins to their bacterial and eukaryotic counterparts to predict functional divergence. We also aim to clone and express these proteins in heterologous system and study their biophysical characteristics in detail using techniques like CD and fluorescence spectroscopy. Overall we aim to understand the features contributing to the folding, stability and dynamics of the archaeal cyclophilin proteins.

Keywords: biophysical characterization, x-ray crystallography, chaperone-like activity, cyclophilin, PPIase activity

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2110 Determination and Distribution of Formation Thickness Using Seismic and Well Data in Baga/Lake Sub-basin, Chad Basin Nigeria

Authors: Gabriel Efomeh Omolaiye, Olatunji Seminu, Jimoh Ajadi, Yusuf Ayoola Jimoh

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The Nigerian part of the Chad Basin till date has been one of the few critically studied basins, with few published scholarly works, compared to other basins such as Niger Delta, Dahomey, etc. This work was undertaken by the integration of 3D seismic interpretations and the well data analysis of eight wells fairly distributed in block A, Baga/Lake sub-basin in Borno basin with the aim of determining the thickness of Chad, Kerri-Kerri, Fika, and Gongila Formations in the sub-basin. Da-1 well (type-well) used in this study was subdivided into stratigraphic units based on the regional stratigraphic subdivision of the Chad basin and was later correlated with other wells using similarity of observed log responses. The combined density and sonic logs were used to generate synthetic seismograms for seismic to well ties. Five horizons were mapped, representing the tops of the formations on the 3D seismic data covering the block; average velocity function with maximum error/residual of 0.48% was adopted in the time to depth conversion of all the generated maps. There is a general thickening of sediments from the west to the east, and the estimated thicknesses of the various formations in the Baga/Lake sub-basin are Chad Formation (400-750 m), Kerri-Kerri Formation (300-1200 m), Fika Formation (300-2200 m) and Gongila Formation (100-1300 m). The thickness of the Bima Formation could not be established because the deepest well (Da-1) terminates within the formation. This is a modification to the previous and widely referenced studies of over forty decades that based the estimation of formation thickness within the study area on the observed outcrops at different locations and the use of few well data.

Keywords: Baga/Lake sub-basin, Chad basin, formation thickness, seismic, velocity

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2109 Toward Discovering an Architectural Typology Based on the Theory of Affordance

Authors: Falntina Ahmad Alata, Natheer Abu Obeid

Abstract:

This paper revolves around the concept of affordance. It aims to discover and develop an architectural typology based on the ecological concept of affordance. In order to achieve this aim, an analytical study is conducted and two sources were taken into account: 1- Gibson's definition of the concept of affordance and 2- The researches that are concerned on the affordance categorisation. As a result, this paper concluded 16 typologies of affordances, including the possibilities of mixing them based on both sources. To clarify these typologies and provide further understanding, a wide range of architectural examples are presented and proposed in the paper. To prove this vocabulary’s capability to diagnose and evaluate the affordance of different environments, an experimental study with two processes have been adapted: 1. Diagnostic process: the interpretation of the environments with regards to its affordance by using the new vocabulary (the developed typologies). 2. Evaluating process: the evaluation of the environments that have been interpreted and classified with regards to their affordances. By using the measures of emotional experience (the positive affect ‘PA’ and the negative affect ‘NA’) and the architectural evaluation criteria (beauty, economy and function). The experimental study proves that the typologies are capable of reading the affordance within different environments. Additionally, it explains how these different typologies reflect different interactions based on the previous processes. The data which are concluded from the evaluation of measures explain how different typologies of affordance that have already reflected different environments had different evaluations. In fact, some of them are recommended while the others are not. In other words, the paper draws a roadmap for designers to diagnose, evaluate and analyse the affordance into different architectural environments. After that, it guides them through adapting the best interaction (affordance category), which they intend to adapt into their proposed designs.

Keywords: Affordance theory, Affordance categories, Architectural environments, Architectural Evaluation Criteria (AEC), emotional experience (PA, NA)

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2108 Pelvic Floor Electrophysiology Patterns Associated with Obstructed Defecation

Authors: Emmanuel Kamal Aziz Saba, Gihan Abd El-Lateif Younis El-Tantawi, Mohammed Hamdy Zahran, Ibrahim Khalil Ibrahim, Mohammed Abd El-Salam Shehata, Hussein Al-Moghazy Sultan, Medhat

Abstract:

Pelvic floor electrophysiological tests are essential for assessment of patients with obstructed defecation. The present study was conducted to determine the different patterns of pelvic floor electrophysiology that are associated with obstructed defecation. The present cross sectional study included 25 patients with obstructed defecation. A control group of 20 apparently healthy subjects were included. All patients were subjected to history taking, clinical examination, proctosigmoidoscopy, lateral proctography (evacuation proctography), dynamic pelvic magnetic resonance imaging, anal manometry and electrophysiological studies. Electrophysiological studies were including pudendal nerve motor conduction study, pudendo-anal reflex, needle electromyography of external anal sphincter and puborectalis muscles, pudendal somatosensory evoked potential and tibial somatosensory evoked potential. The control group was subjected to electrophysiological studies which included pudendal nerve motor conduction study, pudendo-anal reflex, pudendal somatosensory evoked potential and tibial somatosensory evoked potential. The most common pelvic floor electrodiagnostic pattern characteristics of obstructed defecation was pudendal neuropathy, denervation and anismus of external anal sphincter and puborectalis with complete interference pattern of external anal sphincter and puborectalis at squeezing and cough and no localized defect in external anal sphincter. In conclusion, there were characteristic pelvic floor electrodiagnostic patterns associated with obstructed defecation.

Keywords: obstructed defecation, pudendal nerve terminal motor latency, pudendoanal reflex, sphincter electromyography

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2107 Plasmonic Nanoshells Based Metabolite Detection for in-vitro Metabolic Diagnostics and Therapeutic Evaluation

Authors: Deepanjali Gurav, Kun Qian

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In-vitro metabolic diagnosis relies on designed materials-based analytical platforms for detection of selected metabolites in biological samples, which has a key role in disease detection and therapeutic evaluation in clinics. However, the basic challenge deals with developing a simple approach for metabolic analysis in bio-samples with high sample complexity and low molecular abundance. In this work, we report a designer plasmonic nanoshells based platform for direct detection of small metabolites in clinical samples for in-vitro metabolic diagnostics. We first synthesized a series of plasmonic core-shell particles with tunable nanoshell structures. The optimized plasmonic nanoshells as new matrices allowed fast, multiplex, sensitive, and selective LDI MS (Laser desorption/ionization mass spectrometry) detection of small metabolites in 0.5 μL of bio-fluids without enrichment or purification. Furthermore, coupling with isotopic quantification of selected metabolites, we demonstrated the use of these plasmonic nanoshells for disease detection and therapeutic evaluation in clinics. For disease detection, we identified patients with postoperative brain infection through glucose quantitation and daily monitoring by cerebrospinal fluid (CSF) analysis. For therapeutic evaluation, we investigated drug distribution in blood and CSF systems and validated the function and permeability of blood-brain/CSF-barriers, during therapeutic treatment of patients with cerebral edema for pharmacokinetic study. Our work sheds light on the design of materials for high-performance metabolic analysis and precision diagnostics in real cases.

Keywords: plasmonic nanoparticles, metabolites, fingerprinting, mass spectrometry, in-vitro diagnostics

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2106 Pain Management Program in Helping Community-Dwelling Older Adults and Their Informal Caregivers to Manage Pain and Related Situations

Authors: Mimi My Tse

Abstract:

The prevalence of chronic non-cancer pain is high among community-dwelling older adults. Pain affects physical and psychosocial abilities. Older adults tend to be less mobile and have a high tendency to fall risk. In addition, older adults with pain are depressed, anxious, and not too willing to join social activities. This will make them feel very lonely and social isolation. Instead of giving pain management education and programs to older adults/clients, both older adults and their caregivers, it is sad to find that the majority of existing services are given to older adults only. Given the importance of family members in increasing compliance with health-promoting programs, we proposed to offer pain management programs to both older adults with his/her caregiver as a “dyad.” We used the Health Promotion Model and implemented a dyadic pain management program (DPM). The DPM is an 8-week group-based program. The DPM comprises 4 weeks of center-based, face-to-face activities and 4 weeks of digital-based activities delivered via a WhatsApp group. There were 30 dyads (15 in the experimental group with DPM and 15 in the control group with pain education pamphlets). Upon the completion of DPM, pain intensity and pain interference were significantly lower in the intervention group as compared to the control group. At the same time, physical function showed significant improvement and lower depression scores in the intervention group. In conclusion, the study highlights the potential benefits of involving caregivers in the management of chronic pain for older adults. This approach should be widely promoted in managing chronic pain situations for community-dwelling older adults and their caregivers.

Keywords: pain, older adults, dyadic approach, education

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2105 Public Debt Shocks and Public Goods Provisioning in Nigeria: Implication for National Development

Authors: Amenawo I. Offiong, Hodo B. Riman

Abstract:

Public debt profile of Nigeria has continuously been on the increase over the years. The drop in international crude oil prices has further worsened revenue position of the country, thus, necessitating further acquisition of public debt to bridge the gap in revenue deficit. Yet, when we look back at the increasing public sector spending, there are concerns that the government spending do not amount to increase in public goods provided for the country. Using data from 1980 to 2014 the study therefore seeks to investigate the factors responsible for the poor provision of public goods in the face of increasing public debt profile. Using the unrestricted VAR model Governance and Tax revenue were introduced into the model as structural variables. The result suggested that governance and tax revenue were structural determinants of the effectiveness of public goods provisioning in Nigeria. The study therefore identified weak governance as the major reason for the non-provision of public goods in Nigeria. While tax revenue exerted positive influence on the provisions of public goods, weak/poor governance was observed to crowd the benefits from increase tax revenue. The study therefore recommends reappraisal of the governance system in Nigeria. Elected officers in governance should be more transparent and accountable to the electorates they represent. Furthermore, the study advocates for an annual auditing of all government MDAs accounts by external auditors to ensure (a) accountability of public debts utilization, (b) transparent in implementation of program support funds, (c) integrity of agencies responsible for program management, and (d) measuring program effectiveness with amount of funds expended.

Keywords: impulse response function, public debt shocks, governance, public goods, tax revenue, vector auto-regression

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2104 Comparison of Steel and Composite Analysis of a Multi-Storey Building

Authors: Çiğdem Avcı Karataş

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Mitigation of structural damage caused by earthquake and reduction of fatality is one of the main concerns of engineers in seismic prone zones of the world. To achieve this aim many technologies have been developed in the last decades and applied in construction and retrofit of structures. On the one hand Turkey is well-known a country of high level of seismicity; on the other hand steel-composite structures appear competitive today in this country by comparison with other types of structures, for example only-steel or concrete structures. Composite construction is the dominant form of construction for the multi-storey building sector. The reason why composite construction is often so good can be expressed in one simple way - concrete is good in compression and steel is good in tension. By joining the two materials together structurally these strengths can be exploited to result in a highly efficient design. The reduced self-weight of composite elements has a knock-on effect by reducing the forces in those elements supporting them, including the foundations. The floor depth reductions that can be achieved using composite construction can also provide significant benefits in terms of the costs of services and the building envelope. The scope of this paper covers analysis, materials take-off, cost analysis and economic comparisons of a multi-storey building with composite and steel frames. The aim of this work is to show that designing load carrying systems as composite is more economical than designing as steel. Design of the nine stories building which is under consideration is done according to the regulation of the 2007, Turkish Earthquake Code and by using static and dynamic analysis methods. For the analyses of the steel and composite systems, plastic analysis methods have been used and whereas steel system analyses have been checked in compliance with EC3 and composite system analyses have been checked in compliance with EC4. At the end of the comparisons, it is revealed that composite load carrying systems analysis is more economical than the steel load carrying systems analysis considering the materials to be used in the load carrying system and the workmanship to be spent for this job.

Keywords: composite analysis, earthquake, steel, multi-storey building

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2103 Serum Potassium Before, During and After Exercise at 70% Maximal Heart Rate: The Safe Exercise Dosage Across Different Parameters of Health and Fitness Level

Authors: Omar bin Mihat

Abstract:

The number of sudden deaths is increasing over the past years. These deaths occur not during physical activities but upon cessation. Post-mortem confirms these deaths as cardiac arrest non-specifically. Congenital heart disease is a condition undiagnosed whereby only surface upon physical exertion leading to sudden death is unavoidable. Channelopathy, a condition that refers to any disease from the defect in iron-channel function, particularly the sodium-potassium pump, during the cessation of the exercise can be controlled. The derivation of heart rate return (HRrtn) is a procedure of a control cooling down process according to the heart rate (HR). Empirically, potassium rises linearly with intensity and falls sharply upon abrupt cessation of exertion, resulting in fatal arrhythmia due to hypokalaemia. It is vital that the flux of potassium should be maintained within the normal range during physical activities. To achieve this, the dosage of physical exertion (exercise) should be identified. Various percentages of the intensity of maximum heart rate (MHR) will precipitate different adaptations and remodeling of various organs. 70% of MHR will surface physiological adaptations, including enhancement of endurance, fitness level, and general health, and there was no significant rise of serum potassium (K+) during the entire phase of the treadmill brisk walk at a different rate of perceived exertion (RPE) from the subject of various fitness background. There was also no significant rise in blood pressure (BP) during the entire phase of the treadmill brisk walk, substantiating 70% MHR is the safe dosage across different parameters of health and fitness level.

Keywords: potassium, maximal heart rate, exercise dosage, fitness level

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2102 Multidisciplinary Approach for a Tsunami Reconstruction Plan in Coquimbo, Chile

Authors: Ileen Van den Berg, Reinier J. Daals, Chris E. M. Heuberger, Sven P. Hildering, Bob E. Van Maris, Carla M. Smulders, Rafael Aránguiz

Abstract:

Chile is located along the subduction zone of the Nazca plate beneath the South American plate, where large earthquakes and tsunamis have taken place throughout history. The last significant earthquake (Mw 8.2) occurred in September 2015 and generated a destructive tsunami, which mainly affected the city of Coquimbo (71.33°W, 29.96°S). The inundation area consisted of a beach, damaged seawall, damaged railway, wetland and old neighborhood; therefore, local authorities started a reconstruction process immediately after the event. Moreover, a seismic gap has been identified in the same area, and another large event could take place in the near future. The present work proposed an integrated tsunami reconstruction plan for the city of Coquimbo that considered several variables such as safety, nature & recreation, neighborhood welfare, visual obstruction, infrastructure, construction process, and durability & maintenance. Possible future tsunami scenarios are simulated by means of the Non-hydrostatic Evolution of Ocean WAVEs (NEOWAVE) model with 5 nested grids and a higher grid resolution of ~10 m. Based on the score from a multi-criteria analysis, the costs of the alternatives and a preference for a multifunctional solution, the alternative that includes an elevated coastal road with floodgates to reduce tsunami overtopping and control the return flow of a tsunami was selected as the best solution. It was also observed that the wetlands are significantly restored to their former configuration; moreover, the dynamic behavior of the wetlands is stimulated. The numerical simulation showed that the new coastal protection decreases damage and the probability of loss of life by delaying tsunami arrival time. In addition, new evacuation routes and a smaller inundation zone in the city increase safety for the area.

Keywords: tsunami, Coquimbo, Chile, reconstruction, numerical simulation

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2101 The Fracture Resistance of Zirconia Based Dental Crowns from Cyclic Loading: A Function of Relative Wear Depth

Authors: T. Qasim, B. El Masoud, D. Ailabouni

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This in vitro study focused on investigating the fatigue resistance of veneered zirconia molar crowns with different veneering ceramic thicknesses, simulating the relative wear depths under simulated cyclic loading. A mandibular first molar was prepared and then scanned using computer-aided design/computer-aided manufacturing (CAD/CAM) technology to fabricate 32 zirconia copings of uniform 0.5 mm thickness. The manufactured copings then veneered with 1.5 mm, 1.0 mm, 0.5 mm, and 0.0 mm representing 0%, 33%, 66%, and 100% relative wear of a normal ceramic thickness of 1.5 mm. All samples were thermally aged to 6000 thermo-cycles for 2 minutes with distilled water between 5 ˚C and 55 ˚C. The samples subjected to cyclic fatigue and fracture testing using SD Mechatronik chewing simulator. These samples are loaded up to 1.25x10⁶ cycles or until they fail. During fatigue, testing, extensive cracks were observed in samples with 0.5 mm veneering layer thickness. Veneering layer thickness 1.5-mm group and 1.0-mm group were not different in terms of resisting loads necessary to cause an initial crack or final failure. All ceramic zirconia-based crown restorations with varying occlusal veneering layer thicknesses appeared to be fatigue resistant. Fracture load measurement for all tested groups before and after fatigue loading exceeded the clinical chewing forces in the posterior region. In general, the fracture loads increased after fatigue loading and with the increase in the thickness of the occlusal layering ceramic.

Keywords: all ceramic, cyclic loading, chewing simulator, dental crowns, relative wear, thermally ageing

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2100 Altered Expression of Ubiquitin Editing Complex in Ulcerative Colitis

Authors: Ishani Majumdar, Jaishree Paul

Abstract:

Introduction: Ulcerative Colitis (UC) is an inflammatory disease of the colon resulting from an autoimmune response towards individual’s own microbiota. Excessive inflammation is characterized by hyper-activation of NFkB, a transcription factor regulating expression of various pro-inflammatory genes. The ubiquitin editing complex consisting of TNFAIP3, ITCH, RNF11 and TAX1BP1 maintains homeostatic levels of active NFkB through feedback inhibition and assembles in response to various stimuli that activate NFkB. TNFAIP3 deubiquitinates key signaling molecules involved in NFkB activation pathway. ITCH, RNF11 and TAX1BP1 provide substrate specificity, acting as adaptors for TNFAIP3 function. Aim: This study aimed to find expression of members of the ubiquitin editing complex at the transcript level in inflamed colon tissues of UC patients. Materials and Methods: Colonic biopsy samples were collected from 30 UC patients recruited at Department of Gastroenterology, AIIMS (New Delhi). Control group (n= 10) consisted of individuals undergoing examination for functional disorders. Real Time PCR was used to determine relative expression with GAPDH as housekeeping gene. Results: Expression of members of the ubiquitin editing complex was significantly altered during active disease. Expression of TNFAIP3 was upregulated while concomitant decrease in expression of ITCH, RNF11, TAX1BP1 was seen in UC patients. Discussion: This study reveals that increase in expression of TNFAIP3 was unable to control inflammation during active UC. Further, insufficient upregulation of ITCH, RNF11, TAX1BP1 may limit the formation of the ubiquitin complex and contribute to pathogenesis of UC.

Keywords: altered expression, inflammation, ubiquitin editing complex, ulcerative colitis

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2099 Characterization and Degradation of 3D Printed Polycaprolactone-Freeze Dried Bone Matrix Constructs for Use in Critical Sized Bone Defects

Authors: Samantha Meyr, Eman Mirdamadi, Martha Wang, Tao Lowe, Ryan Smith, Quinn Burke

Abstract:

Critical-sized bone defects (CSD) treatment options remain a major clinical orthopedic challenge. They are uniquely contoured diseased or damaged bones and can be defined as those that will not heal spontaneously and require surgical intervention. Autografts are the current gold standard CSD treatment, which are histocompatible and provoke a minimal immunogenic response; however, they can cause donor site morbidity and will not suffice for the size required for replacement. As an alternative to traditional surgical methods, bone tissue engineering will be implemented via 3D printing methods. A freeze-dried bone matrix (FDBM) is a type of graft material available but will only function as desired when in the presence of bone growth factors. Polycaprolactone (PCL) is a known biodegradable material with good biocompatibility that has been proven manageable in 3D printing as a medical device. A 3D-extrusion printing strategy is introduced to print these materials into scaffolds for bone grafting purposes, which could be more accessible and rapid than the current standard. Mechanical, thermal, cytotoxic, and physical properties were investigated throughout a degradation period of 6 months using fibroblasts and dental pulp stem cells. PCL-FDBM scaffolds were successfully printed with high print fidelity in their respective pore sizes and allograft content. Additionally, we have created a method for evaluating PCL using differential scanning calorimetry (DSC) and have evaluated PCL degradation over roughly 6 months.

Keywords: 3D printing, bone tissue engineering, cytotoxicity, degradation, scaffolds

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2098 Automated Fact-Checking by Incorporating Contextual Knowledge and Multi-Faceted Search

Authors: Wenbo Wang, Yi-Fang Brook Wu

Abstract:

The spread of misinformation and disinformation has become a major concern, particularly with the rise of social media as a primary source of information for many people. As a means to address this phenomenon, automated fact-checking has emerged as a safeguard against the spread of misinformation and disinformation. Existing fact-checking approaches aim to determine whether a news claim is true or false, and they have achieved decent veracity prediction accuracy. However, the state-of-the-art methods rely on manually verified external information to assist the checking model in making judgments, which requires significant human resources. This study introduces a framework, SAC, which focuses on 1) augmenting the representation of a claim by incorporating additional context using general-purpose, comprehensive, and authoritative data; 2) developing a search function to automatically select relevant, new, and credible references; 3) focusing on the important parts of the representations of a claim and its reference that are most relevant to the fact-checking task. The experimental results demonstrate that 1) Augmenting the representations of claims and references through the use of a knowledge base, combined with the multi-head attention technique, contributes to improved performance of fact-checking. 2) SAC with auto-selected references outperforms existing fact-checking approaches with manual selected references. Future directions of this study include I) exploring knowledge graphs in Wikidata to dynamically augment the representations of claims and references without introducing too much noise, II) exploring semantic relations in claims and references to further enhance fact-checking.

Keywords: fact checking, claim verification, deep learning, natural language processing

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2097 Impact of Cd and Pb Impregnation on the Health of an Adult Population Neighbouring a Landfill

Authors: M. Cabral, A. Verdin, G. Garçon, A. Touré, C. Diop, M. Fall, S. Bouhsina, D. Dewaele, F.Cazier, A. Tall Dia, P. Shirali, A. Diouf

Abstract:

This case-control study dealt with the health adverse effects within the population neighboring the Mbeubeuss waste dump, which is located near the district of Malika (Diamalaye II) in Dakar (Senegal). All the household and industrial waste arising from Dakar are stored in this open landfill without being covered and are therefore possible sources of Pb and Cd contaminated air emissions and lixiviates. The objective of this study is part of improving the health of the population neighboring Mbeubeuss by determining Pb and Cd concentrations both in environment and humans, and studying possible renal function alterations within the adults. Soil and air samples were collected in the control site (Darou Salam) and the waste dump neighboring site (Diamalaye II). Control and exposed adults were recruited as living in Darou Salam (n = 52) and in Diamalaye II (n = 77). Pb and Cd concentrations in soil, air and biological samples were determined. Moreover, we were interested in analyzing some impregnation (zinc protoporphyrin, d-aminolevulinic acid dehydratase) and oxidative stress biomarkers (malonedialdehyde, gluthatione status), in addition to several nephrotoxicity parameters (creatinuria, proteinuria, lactate dehydrogenase, CC16 protein, glutathione S-transferase-alpha and retinol binding protein) in blood and/or urine. The results showed the significant Pb and Cd contamination of the soil and air samples derived from the landfill, and therefore of the neighboring population of adults. This critical exposure to environmental Pb and Cd had some harmful consequences for their health, as shown by the reported oxidative stress and nephrotoxicity signs.

Keywords: Pb and Cd environmental exposure, impregnation markers, landfill, nephrotoxicity markers

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2096 An Increase in Glucose Uptake per se is Insufficient to Induce Oxidative Stress and Vascular Endothelial Cell Dysfunction

Authors: Heba Khader, Victor Solodushko, Brian Fouty

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Hyperglycemia is a hallmark of uncontrolled diabetes and causes vascular endothelial dysfunction. An increase in glucose uptake and metabolism by vascular endothelial cells is the presumed trigger for this hyperglycemia-induced dysfunction. Glucose uptake into vascular endothelial cells is mediated largely by Glut-1. Glut-1 is an equilibrative glucose transporter with a Km value of 2 mM. At physiologic glucose concentrations, Glut-1 is almost saturated and, therefore, increasing glucose concentration does not increase glucose uptake unless Glut-1 is upregulated. However, hyperglycemia downregulates Glut-1 and decreases rather than increases glucose uptake in vascular endothelial cells. This apparent discrepancy necessitates further study on the effect of increasing glucose uptake on the oxidative state and function of vascular endothelial cells. To test this, a Tet-on system was generated to conditionally regulate Glut-1 expression in endothelial cells by the addition and removal of doxycycline. Glut-1 overexpression was confirmed by Western blot and radiolabeled glucose uptake measurements. Upregulation of Glut-1 resulted in a 4-fold increase in glucose uptake into endothelial cells as determined by 3H deoxy-D-glucose uptake. Increased glucose uptake through Glut-1 did not induce an oxidative stress nor did it cause endothelial dysfunction in rat pulmonary microvascular endothelial cells determined by monolayer resistance, cell proliferation or advanced glycation end product formation. Increased glucose uptake through Glut-1did not lead to an increase in glucose metabolism, due in part to inhibition of hexokinase in Glut-1 overexpressing cells. In summary, this study demonstrates that increasing glucose uptake and intracellular glucose by overexpression of Glut-1 does not alter the oxidative state of rat pulmonary microvascular endothelial cells or cause endothelial cell dysfunction. These results conflict with the current paradigm that hyperglycemia leads to oxidative stress and endothelial dysfunction in vascular endothelial cells through an increase in glucose uptake.

Keywords: endothelial cells, glucose uptake, Glut1, hyperglycemia

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2095 Urban Block Design's Impact on the Indoor Daylight Quality, Heating and Cooling Loads of Buildings in the Semi-Arid Regions: Duhok City in Kurdistan Region-Iraq as a Case Study

Authors: Kawar Salih

Abstract:

It has been proven that designing sustainable buildings starts from early stages of urban design. The design of urban blocks specifically, is considered as one of the pragmatic strategies of sustainable urbanism. There have been previous studies that focused on the impact of urban block design and regulation on the outdoor thermal comfort in the semi-arid regions. However, no studies have been found that concentrated on that impact on the internal behavior of buildings of those regions specifically the daylight quality and energy performance. Further, most studies on semi-arid regions are focusing only on the cooling load reduction, neglecting the heating load. The study has focused on two parameters of urban block distribution which are the block orientation and the surface-to-volume ratio with the consideration of both heating and cooling loads of buildings. In Duhok (a semi-arid city in Kurdistan region of Iraq), energy consumption and daylight quality of different types of residential blocks have been examined using dynamic simulation. The findings suggest that there is a considerable higher energy load for heating than cooling, contradicting many previous studies about these regions. The results also highlight that the orientation of urban blocks can vary the energy consumption to 8%. Regarding the surface-to-volume ratio (S/V), it was observed that after the twice enlargement of the S/V, the energy consumption increased 15%. Though, the study demonstrates as well that there are opportunities for reducing energy consumption with the increase of the S/V which contradicts many previous research on S/V impacts on energy consumption. These results can help to design urban blocks with the bigger S/V than existing blocks in the city which it can provide better indoor daylight and relatively similar energy consumption.

Keywords: blocke orienation, building energy consumption, urban block design, semi-arid regions, surfacet-to-volume ratio

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2094 Exploring the Intersection of Accounting, Business, and Economics: Bridging Theory and Practice for Sustainable Growth

Authors: Stephen Acheampong Amoafoh

Abstract:

In today's dynamic economic landscape, businesses face multifaceted challenges that demand strategic foresight and informed decision-making. This abstract explores the pivotal role of financial analytics in driving business performance amidst evolving market conditions. By integrating accounting principles with economic insights, organizations can harness the power of data-driven strategies to optimize resource allocation, mitigate risks, and capitalize on emerging opportunities. This presentation will delve into the practical applications of financial analytics across various sectors, highlighting case studies and empirical evidence to underscore its efficacy in enhancing operational efficiency and fostering sustainable growth. From predictive modeling to performance benchmarking, attendees will gain invaluable insights into leveraging advanced analytics tools to drive profitability, streamline processes, and adapt to changing market dynamics. Moreover, this abstract will address the ethical considerations inherent in financial analytics, emphasizing the importance of transparency, integrity, and accountability in data-driven decision-making. By fostering a culture of ethical conduct and responsible stewardship, organizations can build trust with stakeholders and safeguard their long-term viability in an increasingly interconnected global economy. Ultimately, this abstract aims to stimulate dialogue and collaboration among scholars, practitioners, and policymakers, fostering knowledge exchange and innovation in the realms of accounting, business, and economics. Through interdisciplinary insights and actionable recommendations, participants will be equipped to navigate the complexities of today's business environment and seize opportunities for sustainable success.

Keywords: financial analytics, business performance, data-driven strategies, sustainable growth

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2093 Surface Induced Alteration of Nanosized Amorphous Alumina

Authors: A. Katsman, L. Bloch, Y. Etinger, Y. Kauffmann, B. Pokroy

Abstract:

Various nanosized amorphous alumina thin films in the range of (2.4 - 63.1) nm were deposited onto amorphous carbon and amorphous Si3N4 membrane grids. Transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), X-ray photoelectron spectroscopy (XPS) and differential scanning calorimetry (DSC) techniques were used to probe the size effect on the short range order and the amorphous to crystalline phase transition temperature. It was found that the short-range order changes as a function of size: the fraction of tetrahedral Al sites is greater in thinner amorphous films. This result correlates with the change of amorphous alumina density with the film thickness demonstrated by the reflectivity experiments: the thinner amorphous films have the less density. These effects are discussed in terms of surface reconstruction of the amorphous alumina films. The average atomic binding energy in the thin film layer decreases with decease of the thickness, while the average O-Al interatomic distance increases. The reconstruction of amorphous alumina is induced by the surface reconstruction, and the short range order changes being dependent on the density. Decrease of the surface energy during reconstruction is the driving force of the alumina reconstruction (density change) followed by relaxation process (short range order change). The amorphous to crystalline phase transition temperature measured by DSC rises with the decrease in thickness from 997.6°C for 13.9 nm to 1020.4 °C for 2.7 nm thick. This effect was attributed to the different film densities: formation of nanovoids preceding and accompanying crystallization process influences the crystallization rate, and by these means, the temperature of crystallization peak.

Keywords: amorphous alumina, density, short range order, size effect

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2092 Optimizing Organizational Performance: The Critical Role of Headcount Budgeting in Strategic Alignment and Financial Stability

Authors: Shobhit Mittal

Abstract:

Headcount budgeting stands as a pivotal element in organizational financial management, extending beyond traditional budgeting to encompass strategic resource allocation for workforce-related expenses. This process is integral to maintaining financial stability and fostering a productive workforce, requiring a comprehensive analysis of factors such as market trends, business growth projections, and evolving workforce skill requirements. It demands a collaborative approach, primarily involving Human Resources (HR) and finance departments, to align workforce planning with an organization's financial capabilities and strategic objectives. The dynamic nature of headcount budgeting necessitates continuous monitoring and adjustment in response to economic fluctuations, business strategy shifts, technological advancements, and market dynamics. Its significance in talent management is also highlighted, aligning financial planning with talent acquisition and retention strategies to ensure a competitive edge in the market. The consequences of incorrect headcount budgeting are explored, showing how it can lead to financial strain, operational inefficiencies, and hindered strategic objectives. Examining case studies like IBM's strategic workforce rebalancing and Microsoft's shift for long-term success, the importance of aligning headcount budgeting with organizational goals is underscored. These examples illustrate that effective headcount budgeting transcends its role as a financial tool, emerging as a strategic element crucial for an organization's success. This necessitates continuous refinement and adaptation to align with evolving business goals and market conditions, highlighting its role as a key driver in organizational success and sustainability.

Keywords: strategic planning, fiscal budget, headcount planning, resource allocation, financial management, decision-making, operational efficiency, risk management, headcount budget

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2091 Shaking the Iceberg: Metaphoric Shifting and Loss in the German Translations of 'The Sun Also Rises'

Authors: Christopher Dick

Abstract:

While the translation of 'literal language' poses numerous challenges for the translator, the translation of 'figurative language' creates even more complicated issues. It has been only in the last several decades that scholars have attempted to propose theories of figurative language translation, including metaphor translation. Even less work has applied these theories to metaphoric translation in literary texts. And almost no work has linked an analysis of metaphors in translation with the recent scholarship on conceptual metaphors. A study of literature in translation must not only examine the inevitable shifts that occur as specific metaphors move from source language to target language but also analyze the ways in which these shifts impact conceptual metaphors and, ultimately, the text as a whole. Doing so contributes to on-going efforts to bridge the sometimes wide gulf between considerations of content and form in literary studies. This paper attempts to add to the body of scholarly literature on metaphor translation and the function of metaphor in a literary text. Specifically, the study examines the metaphoric expressions in Hemingway’s The Sun Also Rises. First, the issue of Hemingway and metaphor is addressed. Next, the study examines the specific metaphors in the original novel in English and the German translations, first in Annemarie Horschitz’s 1928 German version and then in the recent Werner Schmitz 2013 translation. Hemingway’s metaphors, far from being random occurrences of figurative language, are linguistic manifestations of deeper conceptual metaphors that are central to an interpretation of the text. By examining the modifications that are made to these original metaphoric expressions as they are translated into German, one can begin to appreciate the shifts involved with metaphor translation. The translation of Hemingway’s metaphors into German represents significant metaphoric loss and shifting that subsequently shakes the important conceptual metaphors in the novel.

Keywords: Hemingway, Conceptual Metaphor, Translation, Stylistics

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2090 An Analytical Study on the Effect of Chronic Liver Disease Severity and Etiology on Lipid Profiles

Authors: Thinakar Mani Balusamy, Venkateswaran A. R., Bharat Narasimhan, Ratnakar Kini S., Kani Sheikh M., Prem Kumar K., Pugazhendi Thangavelu, Arun Murugan, Sibi Thooran Karmegam, Radhakrishnan N., Mohammed Noufal, Amit Soni

Abstract:

Background and Aims: The liver is integral to lipid metabolism, and a compromise in its function leads to perturbations in these pathways. In this study, we hope to determine the correlation between CLD severity and its effect on lipid parameters. We also look at the etiology-specific effects on lipid levels. Materials and Methods: This is a retrospective cross-sectional analysis of 250 patients with cirrhosis compared to 250 healthy age and sex-matched controls. Severity assessment of CLD using MELD and Child-Pugh scores was performed and etiological details collected. A questionnaire was used to obtain patient demographic details and lastly, a fasting lipid profile (Total, LDL, HDL cholesterol, Triglycerides and VLDL) was obtained. Results: All components of the lipid profile declined linearly with increasing severity of CLD as determined by MELD and Child-Pugh scores. Lipid levels were clearly lower in CLD patients as compared to healthy controls. Interestingly, preliminary analysis indicated that CLD of different etiologies had differential effects on Lipid profiles. This aspect is under further analysis. Conclusion: All components of the lipid profile were definitely lower in CLD patients as compared to controls and demonstrated an inverse correlation with increasing severity. The utilization of this parameter as a prognosticating aid requires further study. Additionally, preliminary analysis indicates that various CLD etiologies appear to have specific effects on the lipid profile – a finding under further analysis.

Keywords: CLD, cholesterol, HDL, LDL, lipid profile, triglycerides, VLDL

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2089 Tourism and Marketing: An Exploration Study to the Strategic Market Analysis of Moses Mabhida Stadium as a Major Tourism Destination in Kwazulu-Natal

Authors: Nduduzo Andrias Ngxongo, Nsizwazikhona Simon Chili

Abstract:

This analytical exploration illustrates how the non-existence of a proper marketing strategy for a tourism destination may have resulted in a radical decline in both financial outputs and visitor arrivals. The marketing strategy is considered as the foundation for any tourism destination’s marketing tactics. Tourism destinations are ought to have dynamic and adaptive marketing strategies that will develop a promotional approach to help the destination to gain market share, identify its target markets, stay relevant to its existing clients, attract new visitors, and increase profits-earned. Accordingly, the Moses Mabhida Stadium (MMS), one of the prominent tourist attractions in KwaZulu-Natal; boasting a world-class architectural design, several international prestigious awards, and vibrant, adventurous activities, has in recent years suffered a gradual slump in both visitors and profits. Therefore, the basis of this paper was to thoroughly establish precisely how the existing MMS marketing strategy may be a basis for a decline in the number of visitors and profits-earned in recent years. The study adopted mixed method research strategy, with 380 participants. The outcome of the study suggests some costly disparities in the marketing strategy of MMS which has led to poor performance and a loss in tourism market share. In consequence, the outcome further suggests that the non-existence of market research analysis and destination marketing tools contributed vastly to the in-progress dilemma. This fact-finding exploration provides a birds-eye outlook of MMS marketing strategy, and based on the results, the study recommends for the introduction of a more far-reaching and revitalising marketing strategy through; constant and persistent market research initiatives, minimal political interference in the administration of state-funded organisations, reassessment of the feasibility study, vigorous, and sourcing of proficient personnel.

Keywords: tourism, destination, marketing , marketing strategy

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2088 Valorization of Sargassum: Use of Twin-Screw Extrusion to Produce Biomolecules and Biomaterials

Authors: Bauta J., Raynaud C., Vaca-Medina G., Simon V., Roully A., Vandenbossche V.

Abstract:

Sargassum is a brown algae, originally found in the Sargasso Sea, located in the Caribbean region and the Gulf of Mexico. The flow of Sargassum is becoming a critical environmental problem all over the Caribbean islands particularly. In Guadeloupe alone, around 80,000 tons of seaweed are stranded during the season. Since the appearance of the first waves of Sargassum algae, several measures have been taken to collect them to keep the beaches clean. Nevertheless, 90% of the collected algae are currently stored without recovery. The lack of research initiative demands a more in-depth exploration of Sargassum algae chemistry, targeted towards added value applications and their development. In this context, the aim of the study was to develop a biorefinery process to valorize Sargassum as a source of bioactive natural substances and as raw material to produce biomaterials simultaneously. The technology used was the twin-screw extrusion, which allows to achieve continuously in the same machine different unit fractionation operations. After the identification of the molecules of interest in Sargassum algae, different operating conditions of thermo-mechanical treatment were applied in a twin-screw extruder. The nature of the solvent, the configuration of the extruder, the screw profile, and the temperature profile were studied in order to fractionate the algal biomass and to allow the recovery of a bioactive liquid fraction of interest and a solid residue suitable for the production of biomaterials. Each bioactive liquid fraction was characterized and strategic ways of adding value were proposed. In parallel, the possibility of using the solid residue to produce biomaterials was studied by setting up Dynamic Vapour Sorption (DVS) and basic Pressure-Volume-Temperature (PVT) analyses. The solid residue was molded by compression cooking. The obtained materials were finally characterized mechanically. The results obtained were very comforting and gave some perspectives to find an interesting valorization for the Sargassum algae.

Keywords: seaweeds, twin-screw extrusion, fractionation, bioactive compounds, biomaterials, biomass

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2087 Single-Molecule Optical Study of Cholesterol-Mediated Dimerization Process of EGFRs in Different Cell Lines

Authors: Chien Y. Lin, Jung Y. Huang, Leu-Wei Lo

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A growing body of data reveals that the membrane cholesterol molecules can alter the signaling pathways of living cells. However, the understanding about how membrane cholesterol modulates receptor proteins is still lacking. Single-molecule tracking can effectively probe into the microscopic environments and thermal fluctuations of receptor proteins in a living cell. In this study we applies single-molecule optical tracking on ligand-induced dimerization process of EGFRs in the plasma membranes of two cancer cell lines (HeLa and A431) and one normal endothelial cell line (MCF12A). We tracked individual EGFR and dual receptors, diffusing in a correlated manner in the plasma membranes of live cells. We developed an energetic model by integrating the generalized Langevin equation with the Cahn-Hilliard equation to help extracting important information from single-molecule trajectories. From the study, we discovered that ligand-bound EGFRs move from non-raft areas into lipid raft domains. This ligand-induced motion is a common behavior in both cancer and normal cells. By manipulating the total amount of membrane cholesterol with methyl-β-cyclodextrin and the local concentration of membrane cholesterol with nystatin, we further found that the amount of cholesterol can affect the stability of EGFR dimers. The EGFR dimers in the plasma membrane of normal cells are more sensitive to the local concentration changes of cholesterol than EGFR dimers in the cancer cells. Our method successfully captures dynamic interactions of receptors at the single-molecule level and provides insight into the functional architecture of both the diffusing EGFR molecules and their local cellular environment.

Keywords: membrane proteins, single-molecule tracking, Cahn-Hilliard equation, EGFR dimers

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2086 The Effect of Iconic and Beat Gestures on Memory Recall in Greek’s First and Second Language

Authors: Eleni Ioanna Levantinou

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Gestures play a major role in comprehension and memory recall due to the fact that aid the efficient channel of the meaning and support listeners’ comprehension and memory. In the present study, the assistance of two kinds of gestures (iconic and beat gestures) is tested in regards to memory and recall. The hypothesis investigated here is whether or not iconic and beat gestures provide assistance in memory and recall in Greek and in Greek speakers’ second language. Two groups of participants were formed, one comprising Greeks that reside in Athens and one with Greeks that reside in Copenhagen. Three kinds of stimuli were used: A video with words accompanied with iconic gestures, a video with words accompanied with beat gestures and a video with words alone. The languages used are Greek and English. The words in the English videos were spoken by a native English speaker and by a Greek speaker talking English. The reason for this is that when it comes to beat gestures that serve a meta-cognitive function and are generated according to the intonation of a language, prosody plays a major role. Thus, participants that have different influences in prosody may generate different results from rhythmic gestures. Memory recall was assessed by asking the participants to try to remember as many words as they could after viewing each video. Results show that iconic gestures provide significant assistance in memory and recall in Greek and in English whether they are produced by a native or a second language speaker. In the case of beat gestures though, the findings indicate that beat gestures may not play such a significant role in Greek language. As far as intonation is concerned, a significant difference was not found in the case of beat gestures produced by a native English speaker and by a Greek speaker talking English.

Keywords: first language, gestures, memory, second language acquisition

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2085 Rare-Earth Ions Doped Lithium Niobate Crystals: Luminescence and Raman Spectroscopy

Authors: Ninel Kokanyan, Edvard Kokanyan, Anush Movsesyan, Marc D. Fontana

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Lithium Niobate (LN) is one of the widely used ferroelectrics having a wide number of applications such as phase-conjugation, holographic storage, frequency doubling, SAW sensors. Furthermore, the possibility of doping with rare-earth ions leads to new laser applications. Ho and Tm dopants seem interesting due to laser emission obtained at around 2 µm. Raman spectroscopy is a powerful spectroscopic technique providing a possibility to obtain a number of information about physicochemical and also optical properties of a given material. Polarized Raman measurements were carried out on Ho and Tm doped LN crystals with excitation wavelengths of 532nm and 785nm. In obtained Raman anti-Stokes spectra, we detect expected modes according to Raman selection rules. In contrast, Raman Stokes spectra are significantly different compared to what is expected by selection rules. Additional forbidden lines are detected. These lines have quite high intensity and are well defined. Moreover, the intensity of mentioned additional lines increases with an increase of Ho or Tm concentrations in the crystal. These additional lines are attributed to emission lines reflecting the photoluminescence spectra of these crystals. It means that in our case we were able to detect, within a very good resolution, in the same Stokes spectrum, the transitions between the electronic states, and the vibrational states as well. The analysis of these data is reported as a function of Ho and Tm content, for different polarizations and wavelengths, of the incident laser beam. Results also highlight additional information about π and σ polarizations of crystals under study.

Keywords: lithium niobate, Raman spectroscopy, luminescence, rare-earth ions doped lithium niobate

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2084 I Look Powerful So You Will Yield to Me: The Effects of Embodied Power and the Perception of Power on Conflict Management

Authors: Fai-Ho E. Choi, Wing-Tung Au

Abstract:

This study investigated the effects of embodiment on conflict management. As shown in the research literature, the physiological (i.e. bodily postures) can affect the emotional and cognitive proceedings of human beings, but little has been shown on whether such effects would have ramifications in decision-making related to other individuals. In this study, conflict is defined as when two parties have seemingly incompatible goals, and the two have to deal with each other in order to maximize one’s own gain. In a matched-gender experiment, university undergraduate students were randomly assigned to either the high power condition or the low power condition, with participants in each condition instructed to perform a fix set of bodily postures that would either embody them with a high sense of power or a low sense of power. One high-power participant would pair up with a low-power participant to engage in an integrative bargaining task and a dictator game. Participants also filled out a pre-trial questionnaire and a post-trial questionnaire measuring general sense of power, self-esteem and self-efficacy. Personality was controlled for. Results are expected to support our hypotheses that people who are embodied with power will be more unyielding in a conflict management situation, and that people who are dealing with another person embodied with power will be more yielding in a conflict management situation. As conflicts arise frequently both within and between organizations, a better understanding of how human beings function in conflicts is important. This study should provide evidence that bodily postures can influence the perceived sense of power of the parties involved and hence influence the conflict outcomes. Future research needs to be conducted to investigate further how people perceive themselves and how they perceive their opponents in conflicts, such that we can come up with a behavioral theory of conflict management.

Keywords: conflict management, embodiment, negotiation, perception

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2083 Modeling and System Identification of a Variable Excited Linear Direct Drive

Authors: Heiko Weiß, Andreas Meister, Christoph Ament, Nils Dreifke

Abstract:

Linear actuators are deployed in a wide range of applications. This paper presents the modeling and system identification of a variable excited linear direct drive (LDD). The LDD is designed based on linear hybrid stepper technology exhibiting the characteristic tooth structure of mover and stator. A three-phase topology provides the thrust force caused by alternating strengthening and weakening of the flux of the legs. To achieve best possible synchronous operation, the phases are commutated sinusoidal. Despite the fact that these LDDs provide high dynamics and drive forces, noise emission limits their operation in calm workspaces. To overcome this drawback an additional excitation of the magnetic circuit is introduced to LDD using additional enabling coils instead of permanent magnets. The new degree of freedom can be used to reduce force variations and related noise by varying the excitation flux that is usually generated by permanent magnets. Hence, an identified simulation model is necessary to analyze the effects of this modification. Especially the force variations must be modeled well in order to reduce them sufficiently. The model can be divided into three parts: the current dynamics, the mechanics and the force functions. These subsystems are described with differential equations or nonlinear analytic functions, respectively. Ordinary nonlinear differential equations are derived and transformed into state space representation. Experiments have been carried out on a test rig to identify the system parameters of the complete model. Static and dynamic simulation based optimizations are utilized for identification. The results are verified in time and frequency domain. Finally, the identified model provides a basis for later design of control strategies to reduce existing force variations.

Keywords: force variations, linear direct drive, modeling and system identification, variable excitation flux

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