Search results for: joint confinement
677 Human Posture Estimation Based on Multiple Viewpoints
Authors: Jiahe Liu, HongyangYu, Feng Qian, Miao Luo
Abstract:
This study aimed to address the problem of improving the confidence of key points by fusing multi-view information, thereby estimating human posture more accurately. We first obtained multi-view image information and then used the MvP algorithm to fuse this multi-view information together to obtain a set of high-confidence human key points. We used these as the input for the Spatio-Temporal Graph Convolution (ST-GCN). ST-GCN is a deep learning model used for processing spatio-temporal data, which can effectively capture spatio-temporal relationships in video sequences. By using the MvP algorithm to fuse multi-view information and inputting it into the spatio-temporal graph convolution model, this study provides an effective method to improve the accuracy of human posture estimation and provides strong support for further research and application in related fields.Keywords: multi-view, pose estimation, ST-GCN, joint fusion
Procedia PDF Downloads 61676 Joint Discrete Hartley Transform-Clipping for Peak to Average Power Ratio Reduction in Orthogonal Frequency Division Multiplexing System
Authors: Selcuk Comlekci, Mohammed Aboajmaa
Abstract:
Orthogonal frequency division multiplexing (OFDM) is promising technique for the modern wireless communications systems due to its robustness against multipath environment. The high peak to average power ratio (PAPR) of the transmitted signal is one of the major drawbacks of OFDM system, PAPR degrade the performance of bit error rate (BER) and effect on the linear characteristics of high power amplifier (HPA). In this paper, we proposed DHT-Clipping reduction technique to reduce the high PAPR by the combination between discrete Hartley transform (DHT) and Clipping techniques. From the simulation results, we notified that DHT-Clipping technique offers better PAPR reduction than DHT and Clipping, as well as DHT-Clipping introduce improved BER performance better than clipping.Keywords: ISI, cyclic prefix, BER, PAPR, HPA, DHT, subcarrier
Procedia PDF Downloads 435675 Dynamic Modeling of a Robot for Playing a Curved 3D Percussion Instrument Utilizing a Finite Element Method
Authors: Prakash Persad, Kelvin Loutan, Trichelle Seepersad
Abstract:
The Finite Element Method is commonly used in the analysis of flexible manipulators to predict elastic displacements and develop joint control schemes for reducing positioning error. In order to preserve simplicity, regular geometries, ideal joints and connections are assumed. This paper presents the dynamic FE analysis of a 4- degrees of freedom open chain manipulator, intended for striking a curved 3D surface percussion musical instrument. This was done utilizing the new MultiBody Dynamics Module in COMSOL, capable of modeling the elastic behavior of a body undergoing rigid body type motion.Keywords: dynamic modeling, entertainment robots, finite element method, flexible robot manipulators, multibody dynamics, musical robots
Procedia PDF Downloads 333674 The International Labor Organization and the Formulation of International Labor Standards
Authors: Tahraoui Boualem
Abstract:
The International Labor Organization is one of the specialized agencies of the United Nations, and it is the only organization within the United Nations system that is distinguished by its tripartite legitimacy and which simultaneously includes governments, workers' and employers' organizations of its member states in a joint effort to set standards and policies Work to promote decent work in various parts of the world, and the expression of international labor standards basically means two types of documents, namely international labor agreements and international labor recommendations, and so far its general conference, which is held annually, has set a number of standards, the number of which has reached 184 agreements and 192 recommendations so far. For this reason, it is decided to clarify the International Labor Organization and the formulation of international labor standards within two sections. In the first topic, the researcher discusses the concept of the International Labor Organization, and in the second topic, it highlights the legal basis for the authority of the International Labor Organization in protecting the rights of workers.Keywords: international labor, international labor standards, rights of workers, nation’s system
Procedia PDF Downloads 65673 Prevalence of Dens Evaginatus in Adolescent Population of Melaka: A Retrospective Study
Authors: Preethy Mary Donald, Renjith George Pallivathukal
Abstract:
Dens evaginatus (DE) is a rare developmental anomaly characterized by a slender enamel-covered tubercle which projects from the occlusal surface of an otherwise normal premolar. DE can often interfere normal occlusion and can lead to complications like sensitivity, pulpal exposure and temporo mandibular joint problems. The orthopantomographs (OPGs) and dental records of patients under the age of 20 who attended the faculty of dentistry, Melaka-Manipal Medical College were examined for DE. Results: The prevalence of DE was 23% among the study group. Males presented with a higher prevalence of 67% and females with 33%. The prevalence of Dens evaginatus was distributed as 28% in maxillary central incisor, 52% in maxillary lateral incisors, 12% in mandibular second premolars. Prevalence in permanent dentitions appeared to be higher than deciduous dentition. The bilateral occurrence of Dens evaginatus is an interesting phenomenon. 57% of the cases of the DE were bilateral.Keywords: deciduous dentition, dens evaginatus, permanent dentition, prevalence
Procedia PDF Downloads 300672 Science and Monitoring Underpinning River Restoration: A Case Study
Authors: Geoffrey Gilfillan, Peter Barham, Lisa Smallwood, David Harper
Abstract:
The ‘Welland for People and Wildlife’ project aimed to improve the River Welland’s ecology and water quality, and to make it more accessible to the community of Market Harborough. A joint monitoring project by the Welland Rivers Trust & University of Leicester was incorporated into the design. The techniques that have been used to measure its success are hydrological, geomorphological, and water quality monitoring, species and habitat surveys, and community engagement. Early results show improvements to flow and habitat diversity, water quality and biodiversity of the river environment. Barrier removal has increased stickleback mating activity, and decreased parasitically infected fish in sample catches. The habitats provided by the berms now boast over 25 native plant species, and the river is clearer, cleaner and with better-oxygenated water.Keywords: community engagement, ecological monitoring, river restoration, water quality
Procedia PDF Downloads 226671 The Professionalisation of British Intelligence Analysts
Authors: Michael S. Goodman
Abstract:
The Joint Intelligence Committee (JIC) has been the senior most analytical body in the UK since its creation in 1936. At various points in its history, most notably and recently in 2004, in the wake of the Iraq war, questions have been asked about its analytical process. In 1968 the British intelligence community saw one of its biggest transformations: the creation of an independent, central cadre of analysts. The ‘Assessments Staff’ was a novel attempt to improve the quality of analysis by fostering independence from departmental biases that had long plagued British intelligence. Seconded into the Cabinet Office, staff were allocated a ‘desk,’ and their role was to produce high level assessments for the most senior readers in the land. At the same time, efforts were made to ‘professionalise’ the analysts. This paper is based on a detailed archival examination of the JIC’s documentary files. It will recount the reasons behind this organisational reform, what the changes entailed, and whether they were a success. The changes were immediately brought to bear with the intelligence assessments prior to the Soviet invasion of Czechoslovakia, something that the JIC failed to appreciate.Keywords: intelligence, cold war history, analysis, united kingdom
Procedia PDF Downloads 68670 The Cross-cultural Adaptation Experience of Foreign Scholars in China
Authors: Jiexiu Chen
Abstract:
This research aims to examine several vital issues relating to the foreign scholars’ cross-cultural adaptation in China, including how they perceive about the adaptation process, what the affecting factors are in the adaptation, and which strategies they will apply to deal with perceived cultural differences. The target population of this research is academics regularly working or long-term visiting in these joint colleges, and semi-structured interviews are used in data collection. Moreover, the theoretical perspectives mainly include Ward’s sociocultural and psychological adaptation theory, Berry’s adaptation strategies and Black and his colleague’s expatriate’s adjustment model. This research offers an in-depth profile as well as theory-based analysis about this unique group, and the results of this research are profound in offering directory suggestions for foreign scholars to facilitate their adaptation in China better and for the Chinese universities to eliminate intercultural obstacles, and optimize the international cooperation programs in China.Keywords: cross-cultural adaptation, foreign scholars, expatriates
Procedia PDF Downloads 416669 Comparison between Open and Closed System for Dewatering with Geotextile: Field and Comparative Study
Authors: Matheus Müller, Delma Vidal
Abstract:
The present paper aims to expose two techniques of dewatering for sludge, analyzing its operations and dewatering processes, aiming at improving the conditions of disposal of residues with high liquid content. It describes the field tests performed on two geotextile systems, a closed geotextile tube and an open geotextile drying bed, both of which are submitted to two filling cycles. The sludge used in the filling cycles for the field trials is from the water treatment plant of the Technological Center of Aeronautics – CTA, in São José dos Campos, Brazil. Data about volume and height abatement due to the dewatering and consolidation were collected per time, until it was observed constancy. With the laboratory analysis of the sludge allied to the data collected in the field, it was possible to perform a critical comparative study between the observed and the scientific literature, in this way, this paper expresses the data obtained and compares them with the bibliography. The tests were carried out on three fronts: field tests, including the filling cycles of the systems with the sludge from CTA, taking measurements of filling time per cycle and maximum filling height per cycle, heights against the abatement by dewatering of the systems over time; tests carried out in the laboratory, including the characterization of the sludge and removal of material samples from the systems to ascertain the solids content within the systems per time and; comparing the data obtained in the field and laboratory tests with the scientific literature. Through the study, it was possible to perceive that the process of densification of the material inside a closed system, such as the geotextile tube, occurs faster than the observed in the drying bed system. This process of accelerated densification can be brought about by the pumping pressure of the sludge in its filling and by the confinement of the residue through the permeable geotextile membrane (allowing water to pass through), accelerating the process of densification and dewatering by its own weight after the filling with sludge.Keywords: consolidation, dewatering, geotextile drying bed, geotextile tube
Procedia PDF Downloads 120668 Developing Three-Dimensional Digital Image Correlation Method to Detect the Crack Variation at the Joint of Weld Steel Plate
Authors: Ming-Hsiang Shih, Wen-Pei Sung, Shih-Heng Tung
Abstract:
The purposes of hydraulic gate are to maintain the functions of storing and draining water. It bears long-term hydraulic pressure and earthquake force and is very important for reservoir and waterpower plant. The high tensile strength of steel plate is used as constructional material of hydraulic gate. The cracks and rusts, induced by the defects of material, bad construction and seismic excitation and under water respectively, thus, the mechanics phenomena of gate with crack are probing into the cause of stress concentration, induced high crack increase rate, affect the safety and usage of hydroelectric power plant. Stress distribution analysis is a very important and essential surveying technique to analyze bi-material and singular point problems. The finite difference infinitely small element method has been demonstrated, suitable for analyzing the buckling phenomena of welding seam and steel plate with crack. Especially, this method can easily analyze the singularity of kink crack. Nevertheless, the construction form and deformation shape of some gates are three-dimensional system. Therefore, the three-dimensional Digital Image Correlation (DIC) has been developed and applied to analyze the strain variation of steel plate with crack at weld joint. The proposed Digital image correlation (DIC) technique is an only non-contact method for measuring the variation of test object. According to rapid development of digital camera, the cost of this digital image correlation technique has been reduced. Otherwise, this DIC method provides with the advantages of widely practical application of indoor test and field test without the restriction on the size of test object. Thus, the research purpose of this research is to develop and apply this technique to monitor mechanics crack variations of weld steel hydraulic gate and its conformation under action of loading. The imagines can be picked from real time monitoring process to analyze the strain change of each loading stage. The proposed 3-Dimensional digital image correlation method, developed in the study, is applied to analyze the post-buckling phenomenon and buckling tendency of welded steel plate with crack. Then, the stress intensity of 3-dimensional analysis of different materials and enhanced materials in steel plate has been analyzed in this paper. The test results show that this proposed three-dimensional DIC method can precisely detect the crack variation of welded steel plate under different loading stages. Especially, this proposed DIC method can detect and identify the crack position and the other flaws of the welded steel plate that the traditional test methods hardly detect these kind phenomena. Therefore, this proposed three-dimensional DIC method can apply to observe the mechanics phenomena of composite materials subjected to loading and operating.Keywords: welded steel plate, crack variation, three-dimensional digital image correlation (DIC), crack stel plate
Procedia PDF Downloads 517667 Nonlinear Flow Behavior and Validity of the Cubic Law in a Rough Fracture
Authors: Kunwar Mrityunjai Sharma, Trilok Nath Singh
Abstract:
The Navier-Stokes equation is used to study nonlinear fluid flow in rough 2D fractures. The major goal is to investigate the influence of inertial flow owing to fracture wall roughness on nonlinear flow behavior. Roughness profiles are developed using Barton's Joint Roughness Coefficient (JRC) and used as fracture walls to assess wall roughness. Four JRC profiles (5, 11, 15, and 19) are employed in the study, where a higher number indicates higher roughness. A parametric study has been performed using varying pressure gradients, and the corresponding Forchheimer number is calculated to observe the nonlinear behavior. The results indicate that the fracture roughness has a significant effect on the onset of nonlinearity. Additionally, the validity of the cubic law is evaluated and observed that it overestimates the flow in rough fractures and should be used with utmost care.Keywords: fracture flow, nonlinear flow, cubic law, Navier-stokes equation
Procedia PDF Downloads 102666 Mobile Phone Banking Applies and Customer Intention: A Case Study in Libya
Authors: Iman E. Bouthahab, Badea B. Geador
Abstract:
Aim of this paper is to explore the prospect of a new approach of mobile phone banking in Libya. This study evaluates customer knowledge on commercial mobile banking in Libya. To examine the relationship between age, occupation and intention for using mobile banking for commercial purpose, a survey was conducted to gather information from one hundred Libyan bank clients. The results indicate that Libyan customers have accepted the new technology and they are ready to use it. There is no significant joint relationship between age and occupation found in intention to use mobile banking in Libya. On the other hand, the customers’ knowledge about mobile banking has a greater relationship with the intention. This study has implications for demographic researches and consumer behaviour disciplines. It also has profitable implications for banks and managers in Libya, as it will assist in better understanding of the Libyan consumers and their activities, when they develop their market strategies and new service.Keywords: mobile banking, intention, customer knowledge, banks in Libya
Procedia PDF Downloads 427665 Experimental Investigation on the Effect of Bond Thickness on the Interface Behaviour of Fibre Reinforced Polymer Sheet Bonded to Timber
Authors: Abbas Vahedian, Rijun Shrestha, Keith Crews
Abstract:
The bond mechanism between timber and fibre reinforced polymer (FRP) is relatively complex and is influenced by a number of variables including bond thickness, bond width, bond length, material properties, and geometries. This study investigates the influence of bond thickness on the behaviour of interface, failure mode, and bond strength of externally bonded FRP-to-timber interface. In the present study, 106 single shear joint specimens have been investigated. Experiment results showed that higher layers of FRP increase the ultimate load carrying capacity of interface; conversely, such increase led to decrease the slip of interface. Moreover, samples with more layers of FRPs may fail in a brittle manner without noticeable warning that collapse is imminent.Keywords: fibre reinforced polymer, FRP, single shear test, bond thickness, bond strength
Procedia PDF Downloads 220664 ISME: Integrated Style Motion Editor for 3D Humanoid Character
Authors: Ismahafezi Ismail, Mohd Shahrizal Sunar
Abstract:
The motion of a realistic 3D humanoid character is very important especially for the industries developing computer animations and games. However, this type of motion is seen with a very complex dimensional data as well as body position, orientation, and joint rotation. Integrated Style Motion Editor (ISME), on the other hand, is a method used to alter the 3D humanoid motion capture data utilised in computer animation and games development. Therefore, this study was carried out with the purpose of demonstrating a method that is able to manipulate and deform different motion styles by integrating Key Pose Deformation Technique and Trajectory Control Technique. This motion editing method allows the user to generate new motions from the original motion capture data using a simple interface control. Unlike the previous method, our method produces a realistic humanoid motion style in real time.Keywords: computer animation, humanoid motion, motion capture, motion editing
Procedia PDF Downloads 377663 Scheduling Nodes Activity and Data Communication for Target Tracking in Wireless Sensor Networks
Authors: AmirHossein Mohajerzadeh, Mohammad Alishahi, Saeed Aslishahi, Mohsen Zabihi
Abstract:
In this paper, we consider sensor nodes with the capability of measuring the bearings (relative angle to the target). We use geometric methods to select a set of observer nodes which are responsible for collecting data from the target. Considering the characteristics of target tracking applications, it is clear that significant numbers of sensor nodes are usually inactive. Therefore, in order to minimize the total network energy consumption, a set of sensor nodes, called sentinel, is periodically selected for monitoring, controlling the environment and transmitting data through the network. The other nodes are inactive. Furthermore, the proposed algorithm provides a joint scheduling and routing algorithm to transmit data between network nodes and the fusion center (FC) in which not only provides an efficient way to estimate the target position but also provides an efficient target tracking. Performance evaluation confirms the superiority of the proposed algorithm.Keywords: coverage, routing, scheduling, target tracking, wireless sensor networks
Procedia PDF Downloads 372662 Issues and Challenges of Tribals in India: A Case of Andhra Pradesh
Authors: P. Lalitha
Abstract:
Economic and social empowerment and educational upliftment of socially disadvantaged groups and marginalized sections of society is necessary for achieving faster and more inclusive development. Programmes are being implemented through states, government’s apex corporations, and NGOs for the up-liftment of disadvantaged and marginalized sections of society. As per the primary data collected, a majority of tribal land holdings (60%) are below 2 hectare and only 5% are above 10 hectares. However, the ownership of large holdings does not give a distinct advantage unless the land is of good quality. There are areas in which even large holdings beyond 5 hectares are not sufficient to meet the food necessity of the tribal families all-round the year. Some initiatives e.g. grain-golas, jhum cultivation, wadi project, Joint Forest Management(JFM), enhancing Livelihood and Health through Traditional Knowledge Management, Associating Individual Rural Volunteers (IRVs) in SHG Bank Linkage Programme have been taken in various tribal areas of the country.Keywords: tribals, unemployment, health, food
Procedia PDF Downloads 284661 Benefits of The ALIAmide Palmitoyl-Glucosamine Co-Micronized with Curcumin for Osteoarthritis Pain: A Preclinical Study
Authors: Enrico Gugliandolo, Salvatore Cuzzocrea, Rosalia Crupi
Abstract:
Osteoarthritis (OA) is one of the most common chronic pain conditions in dogs and cats. OA pain is currently viewed as a mixed phenomenon involving both inflammatory and neuropathic mechanisms at the peripheral (joint) and central (spinal and supraspinal) levels. Oxidative stress has been implicated in OA pain. Although nonsteroidal anti-inflammatory drugs are commonly prescribed for OA pain, they should be used with caution in pets because of adverse effects in the long term and controversial efficacy on neuropathic pain. An unmet need remains for safe and effective long-term treatments for OA pain. Palmitoyl-glucosamine (PGA) is an analogue of the ALIAamide palmitoylethanolamide, i.e., a body’s own endocannabinoid-like compound playing a sentinel role in nociception. PGA, especially in the micronized formulation, was shown safe and effective in OA pain. The aim of this study was to investigate the effect of a co-micronized formulation of PGA with the natural antioxidant curcumin (PGA-cur) on OA pain. Ten Sprague-Dawley male rats were used for each treatment group. The University of Messina Review Board for the care and use of animals authorized the study. On day 0, rats were anesthetized (5.0% isoflurane in 100% O2) and received intra-articular injection of MIA (3 mg in 25 μl saline) in the right knee joint, with the left being injected an equal volume of saline. Starting the third day after MIA injection, treatments were administered orally three times per week for 21 days, at the following doses: PGA 20 mg/kg, curcumin 10 mg/kg, PGA-cur (2:1 ratio) 30 mg/kg. On day 0 and 3, 7, 14 and 21 days post-injection, mechanical allodynia was measured using a dynamic plantar Von Frey hair aesthesiometer and expressed as paw withdrawal threshold (PWT) and latency (PWL). Motor functional recovery of the rear limb was evaluated on the same time points by walking track analysis using the sciatic functional index. On day 21 post-MIA injection, the concentration of the following inflammatory and nociceptive mediators was measured in serum using commercial ELISA kits: tumor necrosis factor alpha (TNF-α), interleukin-1 beta (IL-1β), nerve growth factor (NGF) and matrix metalloproteinase-1-3-9 (MMP-1, MMP-3, MMP-9). The results were analyzed by ANOVA followed by Bonferroni post-hoc test for multiple comparisons. Micronized PGA reduced neuropathic pain, as shown by the significant higher PWT and PWL values compared to vehicle group (p < 0.0001 for all the evaluated time points). The effect of PGA-cur was superior at all time points (p < 0.005). PGA-cur restored motor function already on day 14 (p < 0.005), while micronized PGA was effective a week later (D21). MIA-induced increase in the serum levels of all the investigated mediators was inhibited by PGA-cur (p < 0.01). PGA was also effective, except on IL-1 and MMP-3. Curcumin alone was inactive in all the experiments at any time point. The encouraging results suggest that PGA-cur may represent a valuable option in OA pain management and warrant further confirmation in well-powered clinical trials.Keywords: ALIAmides, curcumin, osteoarthritis, palmitoyl-glucosamine
Procedia PDF Downloads 108660 Platform Virtual for Joint Amplitude Measurement Based in MEMS
Authors: Mauro Callejas-Cuervo, Andrea C. Alarcon-Aldana, Andres F. Ruiz-Olaya, Juan C. Alvarez
Abstract:
Motion capture (MC) is the construction of a precise and accurate digital representation of a real motion. Systems have been used in the last years in a wide range of applications, from films special effects and animation, interactive entertainment, medicine, to high competitive sport where a maximum performance and low injury risk during training and competition is seeking. This paper presents an inertial and magnetic sensor based technological platform, intended for particular amplitude monitoring and telerehabilitation processes considering an efficient cost/technical considerations compromise. Our platform particularities offer high social impact possibilities by making telerehabilitation accessible to large population sectors in marginal socio-economic sector, especially in underdeveloped countries that in opposition to developed countries specialist are scarce, and high technology is not available or inexistent. This platform integrates high-resolution low-cost inertial and magnetic sensors with adequate user interfaces and communication protocols to perform a web or other communication networks available diagnosis service. The amplitude information is generated by sensors then transferred to a computing device with adequate interfaces to make it accessible to inexperienced personnel, providing a high social value. Amplitude measurements of the platform virtual system presented a good fit to its respective reference system. Analyzing the robotic arm results (estimation error RMSE 1=2.12° and estimation error RMSE 2=2.28°), it can be observed that during arm motion in any sense, the estimation error is negligible; in fact, error appears only during sense inversion what can easily be explained by the nature of inertial sensors and its relation to acceleration. Inertial sensors present a time constant delay which acts as a first order filter attenuating signals at large acceleration values as is the case for a change of sense in motion. It can be seen a damped response of platform virtual in other images where error analysis show that at maximum amplitude an underestimation of amplitude is present whereas at minimum amplitude estimations an overestimation of amplitude is observed. This work presents and describes the platform virtual as a motion capture system suitable for telerehabilitation with the cost - quality and precision - accessibility relations optimized. These particular characteristics achieved by efficiently using the state of the art of accessible generic technology in sensors and hardware, and adequate software for capture, transmission analysis and visualization, provides the capacity to offer good telerehabilitation services, reaching large more or less marginal populations where technologies and specialists are not available but accessible with basic communication networks.Keywords: inertial sensors, joint amplitude measurement, MEMS, telerehabilitation
Procedia PDF Downloads 256659 The Outcome of the Discontinuation of Cheques on Bank Reconciliation
Authors: Estelle Abrahams, Tania Pretorius
Abstract:
A joint media statement by the South African Reserve Bank, the Banking Association of South Africa, the Financial Sector Conduct Authority, and the Payments Association of South Africa was recently published, stating that the receipt or acceptance of cheques will terminate effectively on 31 December 2020. All stakeholders are urged to cease accepting or issuing cheques as a payment method. The purpose of the study is to examine the effect that the discontinuation of the usage of cheques has on bank reconciliations for the subject: economic and management sciences. A literature study was performed to gain insight into the bank reconciliation process to be able to draw conclusions on the outcome of the discontinuation of cheques on the bank reconciliation. The study found that the teaching of the bank reconciliation process will change to introduce new replacement source documents for digital payments, and this impacts the teaching of reconciling differences.Keywords: bank reconciliation, internal control, accounting education, source documents
Procedia PDF Downloads 99658 Non-Linear Vibration and Stability Analysis of an Axially Moving Beam with Rotating-Prismatic Joint
Authors: M. Najafi, F. Rahimi Dehgolan
Abstract:
In this paper, the dynamic modeling of a single-link flexible beam with a tip mass is given by using Hamilton's principle. The link has been rotational and translational motion and it was assumed that the beam is moving with a harmonic velocity about a constant mean velocity. Non-linearity has been introduced by including the non-linear strain to the analysis. Dynamic model is obtained by Euler-Bernoulli beam assumption and modal expansion method. Also, the effects of rotary inertia, axial force, and associated boundary conditions of the dynamic model were analyzed. Since the complex boundary value problem cannot be solved analytically, the multiple scale method is utilized to obtain an approximate solution. Finally, the effects of several conditions on the differences among the behavior of the non-linear term, mean velocity on natural frequencies and the system stability are discussed.Keywords: non-linear vibration, stability, axially moving beam, bifurcation, multiple scales method
Procedia PDF Downloads 360657 Measuring Environmental Efficiency of Energy in OPEC Countries
Authors: Bahram Fathi, Seyedhossein Sajadifar, Naser Khiabani
Abstract:
Data envelopment analysis (DEA) has recently gained popularity in energy efficiency analysis. A common feature of the previously proposed DEA models for measuring energy efficiency performance is that they treat energy consumption as an input within a production framework without considering undesirable outputs. However, energy use results in the generation of undesirable outputs as byproducts of producing desirable outputs. Within a joint production framework of both desirable and undesirable outputs, this paper presents several DEA-type linear programming models for measuring energy efficiency performance. In addition to considering undesirable outputs, our models treat different energy sources as different inputs so that changes in energy mix could be accounted for in evaluating energy efficiency. The proposed models are applied to measure the energy efficiency performances of 12 OPEC countries and the results obtained are presented.Keywords: energy efficiency, undesirable outputs, data envelopment analysis
Procedia PDF Downloads 730656 A Comparison of Two and Three Dimensional Motion Capture Methodologies in the Analysis of Underwater Fly Kicking Kinematics
Authors: Isobel M. Thompson, Dorian Audot, Dominic Hudson, Martin Warner, Joseph Banks
Abstract:
Underwater fly kick is an essential skill in swimming, which can have a considerable impact upon overall race performance in competition, especially in sprint events. Reduced wave drags acting upon the body under the surface means that the underwater fly kick will potentially be the fastest the swimmer is travelling throughout the race. It is therefore critical to understand fly kicking techniques and determining biomechanical factors involved in the performance. Most previous studies assessing fly kick kinematics have focused on two-dimensional analysis; therefore, the three-dimensional elements of the underwater fly kick techniques are not well understood. Those studies that have investigated fly kicking techniques using three-dimensional methodologies have not reported full three-dimensional kinematics for the techniques observed, choosing to focus on one or two joints. There has not been a direct comparison completed on the results obtained using two-dimensional and three-dimensional analysis, and how these different approaches might affect the interpretation of subsequent results. The aim of this research is to quantify the differences in kinematics observed in underwater fly kicks obtained from both two and three-dimensional analyses of the same test conditions. In order to achieve this, a six-camera underwater Qualisys system was used to develop an experimental methodology suitable for assessing the kinematics of swimmer’s starts and turns. The cameras, capturing at a frequency of 100Hz, were arranged along the side of the pool spaced equally up to 20m creating a capture volume of 7m x 2m x 1.5m. Within the measurement volume, error levels were estimated at 0.8%. Prior to pool trials, participants completed a landside calibration in order to define joint center locations, as certain markers became occluded once the swimmer assumed the underwater fly kick position in the pool. Thirty-four reflective markers were placed on key anatomical landmarks, 9 of which were then removed for the pool-based trials. The fly-kick swimming conditions included in the analysis are as follows: maximum effort prone, 100m pace prone, 200m pace prone, 400m pace prone, and maximum pace supine. All trials were completed from a push start to 15m to ensure consistent kick cycles were captured. Both two-dimensional and three-dimensional kinematics are calculated from joint locations, and the results are compared. Key variables reported include kick frequency and kick amplitude, as well as full angular kinematics of the lower body. Key differences in these variables obtained from two-dimensional and three-dimensional analysis are identified. Internal rotation (up to 15º) and external rotation (up to -28º) were observed using three-dimensional methods. Abduction (5º) and adduction (15º) were also reported. These motions are not observed in the two-dimensional analysis. Results also give an indication of different techniques adopted by swimmers at various paces and orientations. The results of this research provide evidence of the strengths of both two dimensional and three dimensional motion capture methods in underwater fly kick, highlighting limitations which could affect the interpretation of results from both methods.Keywords: swimming, underwater fly kick, performance, motion capture
Procedia PDF Downloads 128655 Presidential Interactions with Faculty Senates: Expectations and Practices
Authors: Michael T. Miller, G. David Gearhart
Abstract:
Shared governance is an important element in higher education decision making. Through the joint decision making process, faculty members are provided an opportunity to help shape the future of an institution while increasing support for decisions that are made. Presidents, those leaders who are legally bound to guide their institutions, must find ways to collaborate effectively with faculty members in making decisions, and the first step in this process is understanding when and how presidents and faculty leaders interact. In the current study, a national sample of college presidents reported their preparation for the presidency, their perceptions of the functions of a faculty senate, and ultimately, the locations for important interactions between presidents and faculty senates. Results indicated that presidents, regardless of their preparation, found official functions to be the most important for communicating, although, those presidents with academic backgrounds were more likely to perceive faculty senates as having a role in all aspects of an institutions management.Keywords: college faculty, college president, faculty senate, leadership
Procedia PDF Downloads 119654 Parametric Study for Obtaining the Structural Response of Segmental Tunnels in Soft Soil by Using No-Linear Numerical Models
Authors: Arturo Galván, Jatziri Y. Moreno-Martínez, Israel Enrique Herrera Díaz, José Ramón Gasca Tirado
Abstract:
In recent years, one of the methods most used for the construction of tunnels in soft soil is the shield-driven tunneling. The advantage of this construction technique is that it allows excavating the tunnel while at the same time a primary lining is placed, which consists of precast segments. There are joints between segments, also called longitudinal joints, and joints between rings (called as circumferential joints). This is the reason because of this type of constructions cannot be considered as a continuous structure. The effect of these joints influences in the rigidity of the segmental lining and therefore in its structural response. A parametric study was performed to take into account the effect of different parameters in the structural response of typical segmental tunnels built in soft soil by using non-linear numerical models based on Finite Element Method by means of the software package ANSYS v. 11.0. In the first part of this study, two types of numerical models were performed. In the first one, the segments were modeled by using beam elements based on Timoshenko beam theory whilst the segment joints were modeled by using inelastic rotational springs considering the constitutive moment-rotation relation proposed by Gladwell. In this way, the mechanical behavior of longitudinal joints was simulated. On the other hand for simulating the mechanical behavior of circumferential joints elastic springs were considered. As well as, the stability given by the soil was modeled by means of elastic-linear springs. In the second type of models, the segments were modeled by means of three-dimensional solid elements and the joints with contact elements. In these models, the zone of the joints is modeled as a discontinuous (increasing the computational effort) therefore a discrete model is obtained. With these contact elements the mechanical behavior of joints is simulated considering that when the joint is closed, there is transmission of compressive and shear stresses but not of tensile stresses and when the joint is opened, there is no transmission of stresses. This type of models can detect changes in the geometry because of the relative movement of the elements that form the joints. A comparison between the numerical results with two types of models was carried out. In this way, the hypothesis considered in the simplified models were validated. In addition, the numerical models were calibrated with (Lab-based) experimental results obtained from the literature of a typical tunnel built in Europe. In the second part of this work, a parametric study was performed by using the simplified models due to less used computational effort compared to complex models. In the parametric study, the effect of material properties, the geometry of the tunnel, the arrangement of the longitudinal joints and the coupling of the rings were studied. Finally, it was concluded that the mechanical behavior of segment and ring joints and the arrangement of the segment joints affect the global behavior of the lining. As well as, the effect of the coupling between rings modifies the structural capacity of the lining.Keywords: numerical models, parametric study, segmental tunnels, structural response
Procedia PDF Downloads 224653 An Integral Sustainable Design Evaluation of the 15-Minute City and the Processes of Transferability to Cities of the Global South
Authors: Chitsanzo Isaac
Abstract:
Across the world, the ongoing Covid-19 pandemic has challenged urban systems and policy frameworks, highlighting societal vulnerabilities and systemic inequities among many communities. Measures of confinement and social distancing to contain the Covid-19 virus have fragmented the physical and social fabric of cities. This has caused urban dwellers to reassess how they engage with their urban surroundings and maintain social ties. Urbanists have presented strategies that would allow communities to survive and even thrive, in extraordinary times of crisis like the pandemic. Tactical Urbanism, particularly the 15-Minute City, has gained popularity. It is considered a resilient approach in the global north, however, it’s transferability to the global south has been called into question. To this end, this paper poses the question: to what extent is the 15-Minute City framework integral sustainable design, and are there processes that make it adoptable by cities in the global south? This paper explores four issues using secondary quantitative data analysis and convergence analysis in the Paris and Blantyre urban regions. First, it questions how the 15-Minute City has been defined and measured, and how it impacts urban dwellers. Second, it examines the extent to which the 15-minute city performs under the lens of frameworks such as Wilber’s integral theory and Fleming’s integral sustainable design theory. Thirdly this work examines the processes that can be transferred to developing cities which foster community resilience through the perspectives of experience, behaviors, cultures, and systems. Finally, it reviews the principal ways in which a multi-perspective reality can be the basis for resilient community design and sustainable urban development. This work will shed a light on the importance of a multi-perspective reality as a means of achieving sustainable urban design goals in developing urban areas.Keywords: 15-minute city, developing cities, global south, community resilience, integral sustainable design, systems thinking, complexity, tactical urbanism
Procedia PDF Downloads 140652 Mean Shift-Based Preprocessing Methodology for Improved 3D Buildings Reconstruction
Authors: Nikolaos Vassilas, Theocharis Tsenoglou, Djamchid Ghazanfarpour
Abstract:
In this work we explore the capability of the mean shift algorithm as a powerful preprocessing tool for improving the quality of spatial data, acquired from airborne scanners, from densely built urban areas. On one hand, high resolution image data corrupted by noise caused by lossy compression techniques are appropriately smoothed while at the same time preserving the optical edges and, on the other, low resolution LiDAR data in the form of normalized Digital Surface Map (nDSM) is upsampled through the joint mean shift algorithm. Experiments on both the edge-preserving smoothing and upsampling capabilities using synthetic RGB-z data show that the mean shift algorithm is superior to bilateral filtering as well as to other classical smoothing and upsampling algorithms. Application of the proposed methodology for 3D reconstruction of buildings of a pilot region of Athens, Greece results in a significant visual improvement of the 3D building block model.Keywords: 3D buildings reconstruction, data fusion, data upsampling, mean shift
Procedia PDF Downloads 311651 Austenite Transformation in Duplex Stainless Steels under Fast Cooling Rates
Authors: L. O. Luengas, E. V. Morales, L. F. G. De Souza, I. S. Bott
Abstract:
Duplex Stainless Steels are well known for its good mechanical properties, and corrosion resistance. However, when submitted to heating, these features can be lost since the good properties are strongly dependent on the austenite-ferrite phase ratio which has to be approximately 1:1 to keep the phase balance. In a welded joint, the transformation kinetics at the heat affected zone (HAZ) is a function of the cooling rates applied which in turn are dependent on the heat input. The HAZ is usually ferritized at these temperatures, and it has been argued that small variations of the chemical composition can play a role in the solid state transformation sequence of ferrite to austenite during cooling. The δ → γ transformation has been reported to be massive and diffusionless due to the fast cooling rate, but it is also considered a diffusion controlled transformation. The aim of this work is to evaluate the effect of different heat inputs on the HAZ of two duplex stainless steels UNS S32304 and S32750, obtained by physical simulation.Keywords: duplex stainless steels, HAZ, microstructural characterization, physical simulation
Procedia PDF Downloads 272650 Performance Analysis of the First-Order Characteristics of Polling System Based on Parallel Limited (K=1) Services Mode
Authors: Liu Yi, Bao Liyong
Abstract:
Aiming at the problem of low efficiency of pipelined scheduling in periodic query-qualified service, this paper proposes a system service resource scheduling strategy with parallel optimized qualified service polling control. The paper constructs the polling queuing system and its mathematical model; firstly, the first-order and second-order characteristic parameter equations are obtained by partial derivation of the probability mother function of the system state variables, and the complete mathematical, analytical expressions of each system parameter are deduced after the joint solution. The simulation experimental results are consistent with the theoretical calculated values. The system performance analysis shows that the average captain and average period of the system have been greatly improved, which can better adapt to the service demand of delay-sensitive data in the dense data environment.Keywords: polling, parallel scheduling, mean queue length, average cycle time
Procedia PDF Downloads 33649 Development of Orbital TIG Welding Robot System for the Pipe
Authors: Dongho Kim, Sung Choi, Kyowoong Pee, Youngsik Cho, Seungwoo Jeong, Soo-Ho Kim
Abstract:
This study is about the orbital TIG welding robot system which travels on the guide rail installed on the pipe, and welds and tracks the pipe seam using the LVS (Laser Vision Sensor) joint profile data. The orbital welding robot system consists of the robot, welder, controller, and LVS. Moreover we can define the relationship between welding travel speed and wire feed speed, and we can make the linear equation using the maximum and minimum amount of weld metal. Using the linear equation we can determine the welding travel speed and the wire feed speed accurately corresponding to the area of weld captured by LVS. We applied this orbital TIG welding robot system to the stainless steel or duplex pipe on DSME (Daewoo Shipbuilding and Marine Engineering Co. Ltd.,) shipyard and the result of radiographic test is almost perfect. (Defect rate: 0.033%).Keywords: adaptive welding, automatic welding, pipe welding, orbital welding, laser vision sensor, LVS, welding D/B
Procedia PDF Downloads 676648 The Influence of Fiber Fillers on the Bonding Safety of Structural Adhesives: A Fracture Analytical Evaluation
Authors: Brandtner-Hafner Martin
Abstract:
Adhesives have established themselves as an innovative joining technology in the industry. Their strengths lie in joining different materials, avoiding structural weakening as in welding or screwing, and enabling lightweight construction methods. Now there are a variety of ways to improve the efficiency and effectiveness of bonded joints. One way is to add fiber fillers. This leads to an improvement in adhesion and cohesion (structural integrity). In this study, the effectiveness of fiber-modified adhesives for bonding different construction materials is reviewed. A series of experimental tests were performed using the fracture analytical GF principle to study the adhesive bonding safety and performance of the joint. Three different structural adhesive systems based on epoxy, CA/A hybrid, and PUR were modified with different fiber materials on different substrates. The results show that significant performance improvements can be achieved and that bonding reliability can be sustainably increased.Keywords: fiber-modified adhesives, bonding safety, GF-principle, fracture analysis
Procedia PDF Downloads 165