Search results for: dynamic background
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 8264

Search results for: dynamic background

7124 A Cross Cultural Study of Jewish and Arab Listeners: Perception of Harmonic Sequences

Authors: Roni Granot

Abstract:

Musical intervals are the building blocks of melody and harmony. Intervals differ in terms of their size, direction, or quality as consonants or dissonants. In Western music, perceptual dissonance is mostly associated with the sensation of beats or periodicity, whereas cognitive dissonance is associated with rules of harmony and voice leading. These two perceptions can be studied separately in musical cultures which include melodic with little or no harmonic structures. In the Arab musical system, there is a number of different quarter- tone intervals creating various combinations of consonant and dissonant intervals. While traditional Arab music includes only melody, today’s Arab pop music includes harmonization of songs, often using typical Western harmonic sequences. Therefore, the Arab population in Israel presents an interesting case which enables us to examine the distinction between perceptual and cognitive dissonance. In the current study, we compared the responses of 34 Jewish Western listeners and 56 Arab listeners to two types of stimuli and their relationships: Harmonic sequences and isolated harmonic intervals (dyads). Harmonic sequences were presented in synthesized piano tones and represented five levels of Harmonic prototypicality (Tonic ending; Tonic ending with half flattened third; Deceptive cadence; Half cadence; and Dissonant unrelated ending) and were rated on 5-point scales of closure and surprise. Here we report only findings related to the harmonic sequences. One-way repeated measures ANOVA with one within subjects factor with five levels (Type of sequence) and one between- subjects factor (Musical background) indicates a main effect of Type of sequence for surprise ratings F (4, 85) = 51 p<.001, and for closure ratings F (4, 78) 9.54 p < .001, no main effect of Background on either surprise or closure ratings, and a marginally significant Type X Background interaction for surprise F (4, 352) = 6.05 p = .069 and closure ratings F (4, 324) 3.89 p < .01). Planned comparisons show that the interaction of Type of sequence X Background center around surprise and closure ratings of the regular versus the half- flattened third tonic and the deceptive versus the half cadence. The half- flattened third tonic is rated as less surprising and as demanding less continuation than the regular tonic by the Arab listeners as compared to the Western listeners. In addition, the half cadence is rated as more surprising but demanding less continuation than the deceptive cadence in the Arab listeners as compared to the Western listeners. Together, our results suggest that despite the vast exposure of Arab listeners to Western harmony, sensitivity to harmonic rules seems to be partial with preference to oriental sonorities such as half flattened third. In addition, the percept of directionality which demands sensitivity to the level on which closure is obtained and which is strongly entrenched in Western harmony, may not be fully integrated into the Arab listeners’ mental harmonic scheme. Results will be discussed in terms of broad differences between Western and Eastern aesthetic ideals.

Keywords: harmony, cross cultural, Arab music, closure

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7123 Continuous-Time Analysis And Performance Assessment For Digital Control Of High-Frequency Switching Synchronous Dc-Dc Converter

Authors: Rihab Hamdi, Amel Hadri Hamida, Ouafae Bennis, Sakina Zerouali

Abstract:

This paper features a performance analysis and robustness assessment of a digitally controlled DC-DC three-cell buck converter associated in parallel, operating in continuous conduction mode (CCM), facing feeding parameters variation and loads disturbance. The control strategy relies on the continuous-time with an averaged modeling technique for high-frequency switching converter. The methodology is to modulate the complete design procedure, in regard to the existence of an instantaneous current operating point for designing the digital closed-loop, to the same continuous-time domain. Moreover, the adopted approach is to include a digital voltage control (DVC) technique, taking an account for digital control delays and sampling effects, which aims at improving efficiency and dynamic response and preventing generally undesired phenomena. The results obtained under load change, input change, and reference change clearly demonstrates an excellent dynamic response of the proposed technique, also as provide stability in any operating conditions, the effectiveness is fast with a smooth tracking of the specified output voltage. Simulations studies in MATLAB/Simulink environment are performed to verify the concept.

Keywords: continuous conduction mode, digital control, parallel multi-cells converter, performance analysis, power electronics

Procedia PDF Downloads 147
7122 Seismic Assessment of a Pre-Cast Recycled Concrete Block Arch System

Authors: Amaia Martinez Martinez, Martin Turek, Carlos Ventura, Jay Drew

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This study aims to assess the seismic performance of arch and dome structural systems made from easy to assemble precast blocks of recycled concrete. These systems have been developed by Lock Block Ltd. Company from Vancouver, Canada, as an extension of their currently used retaining wall system. The characterization of the seismic behavior of these structures is performed by a combination of experimental static and dynamic testing, and analytical modeling. For the experimental testing, several tilt tests, as well as a program of shake table testing were undertaken using small scale arch models. A suite of earthquakes with different characteristics from important past events are chosen and scaled properly for the dynamic testing. Shake table testing applying the ground motions in just one direction (in the weak direction of the arch) and in the three directions were conducted and compared. The models were tested with increasing intensity until collapse occurred; which determines the failure level for each earthquake. Since the failure intensity varied with type of earthquake, a sensitivity analysis of the different parameters was performed, being impulses the dominant factor. For all cases, the arches exhibited the typical four-hinge failure mechanism, which was also shown in the analytical model. Experimental testing was also performed reinforcing the arches using a steel band over the structures anchored at both ends of the arch. The models were tested with different pretension levels. The bands were instrumented with strain gauges to measure the force produced by the shaking. These forces were used to develop engineering guidelines for the design of the reinforcement needed for these systems. In addition, an analytical discrete element model was created using 3DEC software. The blocks were designed as rigid blocks, assigning all the properties to the joints including also the contribution of the interlocking shear key between blocks. The model is calibrated to the experimental static tests and validated with the obtained results from the dynamic tests. Then the model can be used to scale up the results to the full scale structure and expanding it to different configurations and boundary conditions.

Keywords: arch, discrete element model, seismic assessment, shake-table testing

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7121 Antecedents of Sport Commitment: A Comparison Based on Demographic Factors

Authors: Navodita Mishra, T. J. Kamalanabhan

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Purpose: The primary purpose of this study was to identify the antecedents of sports commitment among cricket players and to understand demographic variables that may impact these factors. Commitment towards one’s sports plays a crucial role in determining discipline and efforts of the player. Moreover, demographic variables would seem to play an important role in determining which factors or predictors have the greatest impact on commitment level. Design /methodology/approach: This study hypothesized the effect of demographic factors on sports commitment among cricket players. It attempts to examine the extent to which demographic factors can differentially motivate players to exhibit commitment towards their respective sport. Questionnaire survey method was adopted using purposive sampling technique. Using Multiple Regression, ANOVA, and t-test, the hypotheses were tested based on a sample of 350 players from Cricket Academy. Findings: Our main results from the multivariate analysis indicated that enjoyment and leadership of coach and peer affect the level of commitment to a greater extent whereas personal investment is a significant predictor of commitment among rural background players Moreover, level of sport commitment among players is positively related to household income, the rural background players participate in sports to a greater extent than the urban players, there is no evidence of regional differentials in commitment but age differences (i.e. U-19 vs. U-25) play an important role in the decision to continue the participation in sports.

Keywords: Individual Sports Commitment, demographic indicators, cricket, player motivation

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7120 Place, Female and Latino Identities in Kali Fajardo-Anstine’s Short Story Collection Sabrina and Corina

Authors: Jaroslav Kusnir

Abstract:

In her short story collection, Sabrina & Corina, Kali Fajardo-Anstine depicts mostly Latina characters of indigenous background living and travelling in the American West and the Southwest. In all the stories, place and the environment plays an important role in the construction of cultural identity of these characters that is influenced by their indigenous background, a specificity of the American West, its culture and environment, as well as a contemporary (modern) American culture, position of women and gender roles in a Latino community in the USA. This paper will analyze Fajardo-Anstine´s depiction of a specificity of place, especially of the American West and its role in a construction of Latino/a cultural identity in a modern American society as manifested especially in Fajardo-Anstine´s stories Any Further West and Sabrina & Corina. At the same time, the paper will point out Fajardo-Anstine´s construction of cultural identity of female characters and their gender roles in both Latino and a contemporary American societies. The research results show that the formation of Latina cultural identity is closely connected with both place, that is the American West and the Soutwest as well as with Latina and contemporary American cultures.

Keywords: American culture, american west, cultural identity, female identity, latina identity, place

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7119 Determination of Tide Height Using Global Navigation Satellite Systems (GNSS)

Authors: Faisal Alsaaq

Abstract:

Hydrographic surveys have traditionally relied on the availability of tide information for the reduction of sounding observations to a common datum. In most cases, tide information is obtained from tide gauge observations and/or tide predictions over space and time using local, regional or global tide models. While the latter often provides a rather crude approximation, the former relies on tide gauge stations that are spatially restricted, and often have sparse and limited distribution. A more recent method that is increasingly being used is Global Navigation Satellite System (GNSS) positioning which can be utilised to monitor height variations of a vessel or buoy, thus providing information on sea level variations during the time of a hydrographic survey. However, GNSS heights obtained under the dynamic environment of a survey vessel are affected by “non-tidal” processes such as wave activity and the attitude of the vessel (roll, pitch, heave and dynamic draft). This research seeks to examine techniques that separate the tide signal from other non-tidal signals that may be contained in GNSS heights. This requires an investigation of the processes involved and their temporal, spectral and stochastic properties in order to apply suitable recovery techniques of tide information. In addition, different post-mission and near real-time GNSS positioning techniques will be investigated with focus on estimation of height at ocean. Furthermore, the study will investigate the possibility to transfer the chart datums at the location of tide gauges.

Keywords: hydrography, GNSS, datum, tide gauge

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7118 A Multidimensional Genetic Algorithm Applicable for Our VRP Variant Dealing with the Problems of Infrastructure Defaults SVRDP-CMTW: “Safety Vehicle Routing Diagnosis Problem with Control and Modified Time Windows”

Authors: Ben Mansour Mouin, Elloumi Abdelkarim

Abstract:

We will discuss the problem of routing a fleet of different vehicles from a central depot to different types of infrastructure-defaults with dynamic maintenance requests, modified time windows, and control of default maintained. For this reason, we propose a modified metaheuristicto to solve our mathematical model. SVRDP-CMTW is a variant VRP of an optimal vehicle plan that facilitates the maintenance task of different types of infrastructure-defaults. This task will be monitored after the maintenance, based on its priorities, the degree of danger associated with each default, and the neighborhood at the black-spots. We will present, in this paper, a multidimensional genetic algorithm “MGA” by detailing its characteristics, proposed mechanisms, and roles in our work. The coding of this algorithm represents the necessary parameters that characterize each infrastructure-default with the objective of minimizing a combination of cost, distance and maintenance times while satisfying the priority levels of the most urgent defaults. The developed algorithm will allow the dynamic integration of newly detected defaults at the execution time. This result will be displayed in our programmed interactive system at the routing time. This multidimensional genetic algorithm replaces N genetic algorithm to solve P different type problems of infrastructure defaults (instead of N algorithm for P problem we can solve in one multidimensional algorithm simultaneously who can solve all these problemsatonce).

Keywords: mathematical model, VRP, multidimensional genetic algorithm, metaheuristics

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7117 Assessment of Households' Food Security and Hunger Level across Communities in Ile-Ife, Southwestern Nigeria

Authors: Adebayo-Victoria Tobi Dada, Dada Emmanuel

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This study assessed households’ food security and hunger levels among different communities with varying educational and economic background in Ile-Ife, Nigeria, and its environment. It also examined the impacts of varying demography on the household food security level in the area. This was with a view to providing information on the food security status of the subjects within the study area. Ten different communities with varying demography (Parakin, Mokuro, Ilare, Obafemi Awolowo University (OAU) Staff Quarters, Ibadan Road, Aba-Iya Gani, Eleweran, Iraye, Boosa, and Eku-Isobo) were identified within the study area. Fieldwork was then carried out from 7th to 14th of March, 2016 in each of these communities through survey of market prices of food stuff, diet, and nutrition, social well-being, food accessibility and affordability as well as price fluctuation and variation in household’s social background. Selection of households for the survey was done using stratified random sampling method. Key informants included community heads, landlords, tenants, and household heads. Similarly, information on food security levels with respect to demographic backgrounds was obtained from the use of modified Food and Hunger Insecurity Module (FHIM) structured questionnaire. The questionnaire was administered to one percent of the households’ population per community. The results showed that communities such as Parakin and OAU Senior Staff Quarters were dominated by civil servants, while community such as Boosa was dominated by artisans. Respondents earning between ₦11,000 and ₦20,000 per month, during the study period, had the highest percentage across the selected communities. The household food security indices showed that about 41% of the investigated respondents could not guarantee their household food for a month, while 18% reduced or skipped meals. There were positive significant relationships between monthly income (F-value = 132.04), educational status (F-value = 102.30), occupation (F-value = 104.05) and food budget (F-value = 122.09), all at p < 0.05. However, there was no significant relationship between the monthly food budget and household sizes (t-value = -1.4074, p > 0.05). Food secured households’ had the household heads with a higher level of educational attainment. The study concluded that large variations which existed between socio-economic and educational background among the communities had significant effects on households’ food security level in the study area.

Keywords: food security, households, hunger level, market prices

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7116 Effects of Robot-Assisted Hand Training on Upper Extremity Performance in Patients with Stroke: A Randomized Crossover Controlled, Assessor-Blinded Study

Authors: Hsin-Chieh Lee, Fen-Ling Kuo, Jui-Chi Lin

Abstract:

Background: Upper extremity functional impairment that occurs after stroke includes hemiplegia, synergy movement, muscle hypertonicity, and somatosensory impairment, which result in inefficient and inaccurate movement. Robot-assisted rehabilitation is an intensive training approach that is effective in sensorimotor and hand function recovery. However, these systems mostly focused on the proximal part of the upper limb rather than the distal part. The device used in our study was Gloreha Sinfonia, which focuses on the distal part of the upper limb and uses a dynamic support system to facilitate the whole limb function. The objective of this study was to investigate the effects of robot-assisted therapy (RT) with Gloreha device on sensorimotor, and ADLs in patients with stroke. Method: Patients with stroke (N=25) participated AB or BA (A = 12 RT sessions and B = 12 conventional therapy (CT) sessions) for 6 weeks (60 min at each session, twice a week), with 1-month break for washout period. The performance of the patients was assessed by a blinded assessor at 4 time points (pretest 1, posttest 1, pretest 2, posttest 2) which including the Fugl–Meyer Assessment-upper extremity (FMA-UE), box and block test, electromyography of the extensor digitorum communis (EDC) and brachioradialis, a grip dynamometer for motor evaluation; Semmes–Weinstein hand monofilament and Revision of the Nottingham Sensory Assessment for sensory evaluation; and the Modified Barthel Index (MBI) for assessing the ADL ability. Result: RT group significantly improved FMA-UE proximal scores (p = 0.038), FMA-UE total scores (p = 0.046), and MBI (p = 0.030). The EDC exhibited higher efficiency during the small block grasping task in the RT group than in the CT group (p = 0.050). Conclusions: RT with the Gloreha device might lead to beneficial effects on arm motor function, ADL ability, and EDC muscle recruitment efficacy in patients with subacute to chronic stroke.

Keywords: activities of daily living, hand function, robotic rehabilitation, stroke

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7115 Buddhism and Society: The History and Contribution of Buddhist Education in Taiwan

Authors: Meilee Shen

Abstract:

Buddhist monks and nuns have changed within the dynamic culture of Taiwan that they find themselves in. The diverse cultures, economic development, and advanced educational levels of the island are all part of this. Buddhist education has become an interesting aspect in the history of Taiwanese Buddhism. In recent years, Buddhists in Taiwan have made significant contributions to both academic and religious studies. This paper will focus on the following questions: What is Buddhist education? How does a Buddhist education change monastic role in Taiwanese Buddhism? Finally, how has Buddhist education benefited Taiwanese society? Research indicates that Buddhist education in Taiwan possesses four features: 1. Master teaching disciple: Buddhist masters teach monastic rules to monastic disciples only. 2. Monastic education: It is mainly focused on Buddhist doctrines and sangha rules. 3. From Buddhist education to secular education: Buddhist studies were introduced into secular educational environments that were the beginning for outsiders to study Buddhism. It also opened a door to recruit young college students to enter the monastery. 4. Academic Buddhist training: Buddhist monks and nuns have begun to study at secular colleges in various programs besides Buddhist studies. In recent years, Buddhist colleges and secular universities’ religious studies programs have begun to admit overseas students due to the low birth-rate in Taiwan. Therefore, the relationship between Buddhism and Taiwanese society is dynamic.

Keywords: Buddhist college and university in Taiwan, Buddhist education, institutionalization in Taiwanese Buddhism, monastic and secular education, Taiwanese Buddhist monks and nuns

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7114 Development of Industry Oriented Undergraduate Research Program

Authors: Sung Ryong Kim, Hyung Sup Han, Jae-Yup Kim

Abstract:

Many engineering students feel uncomfortable in solving the industry related problems. There are many ways to strengthen the engineering student’s ability to solve the assigned problem when they get a job. Korea National University of Transportation has developed an industry-oriented undergraduate research program (URP). An URP program is designed for engineering students to provide an experience of solving a company’s research problem. The URP project is carried out for 6 months. Each URP team consisted of 1 company mentor, 1 professor, and 3-4 engineering students. A team of different majors is strongly encouraged to integrate different perspectives of multidisciplinary background. The corporate research projects proposed by companies are chosen by the major-related student teams. A company mentor gives the detailed technical background of the project to the students, and he/she also provides a basic data, raw materials and so forth. The company allows students to use the company's research equipment. An assigned professor has adjusted the project scope and level to the student’s ability after discussing with a company mentor. Monthly meeting is used to check the progress, to exchange ideas, and to help the students. It is proven as an effective engineering education program not only to provide an experience of company research but also to motivate the students in their course work. This program provides a premier interdisciplinary platform for undergraduate students to perform the practical challenges encountered in their major-related companies and it is especially helpful for students who want to get a job from a company that proposed the project.

Keywords: company mentor, industry oriented, interdisciplinary platform, undergraduate research program

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7113 The Usefulness and Limitations of Manual Aspiration Immediately after Pneumothorax Complicating Percutaneous CT Guided Lung Biopsies: A Retrospective 9-Year Review from a Large Tertiary Centre

Authors: Niall Fennessy, Charlotte Yin, Vineet Gorolay, Michael Chan, Ilias Drivas

Abstract:

Background: The aim of this study was to evaluate the effect of manual aspiration of air from the pleural cavity in mitigating the need for chest drain placement after a CT-guided lung biopsy. Method: This is a single institution retrospective review of CT-guided lung biopsies performed on 799 patients between September 2013 and May 2021 in a major tertiary hospital. Percutaneous manual aspiration of air was performed in 104/306 patients (34%) with pneumothoraxes as a preventative measure. Simple and multivariate analysis was performed to identify independent risk factors (modifiable and nonmodifiable) for the success of manual aspiration in mitigating the need for chest drain insertion. Results: The overall incidence of pneumothorax was 37% (295/799). Chest drains were inserted for 81/295 (27%) of the pneumothoraxes, representing 81/799 (10%) of all CT-guided lung biopsies. Of patients with pneumothoraces, 104 (36%) underwent percutaneous aspiration via either the coaxial guide needle or an 18 or 20G intravenous catheter attached to a three-way stopcock and syringe. Amongst this group, 13 patients (13%) subsequently required chest drain insertion. The success of percutaneous aspiration in avoiding subsequent pleural drain insertion decreased with aspiration volume >500mL, radial pneumothorax depth >3cm, increased subpleural depth of the lesion, and the presence of background emphysema.

Keywords: computed tomography, lung biopsy, pneumothorax, manual aspiration, chest drainage

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7112 Constructivism and Situational Analysis as Background for Researching Complex Phenomena: Example of Inclusion

Authors: Radim Sip, Denisa Denglerova

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It’s impossible to capture complex phenomena, such as inclusion, with reductionism. The most common form of reductionism is the objectivist approach, where processes and relationships are reduced to entities and clearly outlined phases, with a consequent search for relationships between them. Constructivism as a paradigm and situational analysis as a methodological research portfolio represent a way to avoid the dominant objectivist approach. They work with a situation, i.e. with the essential blending of actors and their environment. Primary transactions are taking place between actors and their surroundings. Researchers create constructs based on their need to solve a problem. Concepts therefore do not describe reality, but rather a complex of real needs in relation to the available options how such needs can be met. For examination of a complex problem, corresponding methodological tools and overall design of the research are necessary. Using an original research on inclusion in the Czech Republic as an example, this contribution demonstrates that inclusion is not a substance easily described, but rather a relationship field changing its forms in response to its actors’ behaviour and current circumstances. Inclusion consists of dynamic relationship between an ideal, real circumstances and ways to achieve such ideal under the given circumstances. Such achievement has many shapes and thus cannot be captured by description of objects. It can be expressed in relationships in the situation defined by time and space. Situational analysis offers tools to examine such phenomena. It understands a situation as a complex of dynamically changing aspects and prefers relationships and positions in the given situation over a clear and final definition of actors, entities, etc. Situational analysis assumes creation of constructs as a tool for solving a problem at hand. It emphasizes the meanings that arise in the process of coordinating human actions, and the discourses through which these meanings are negotiated. Finally, it offers “cartographic tools” (situational maps, socials worlds / arenas maps, positional maps) that are able to capture the complexity in other than linear-analytical ways. This approach allows for inclusion to be described as a complex of phenomena taking place with a certain historical preference, a complex that can be overlooked if analyzed with a more traditional approach.

Keywords: constructivism, situational analysis, objective realism, reductionism, inclusion

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7111 Deep Reinforcement Learning for Advanced Pressure Management in Water Distribution Networks

Authors: Ahmed Negm, George Aggidis, Xiandong Ma

Abstract:

With the diverse nature of urban cities, customer demand patterns, landscape topologies or even seasonal weather trends; managing our water distribution networks (WDNs) has proved a complex task. These unpredictable circumstances manifest as pipe failures, intermittent supply and burst events thus adding to water loss, energy waste and increased carbon emissions. Whilst these events are unavoidable, advanced pressure management has proved an effective tool to control and mitigate them. Henceforth, water utilities have struggled with developing a real-time control method that is resilient when confronting the challenges of water distribution. In this paper we use deep reinforcement learning (DRL) algorithms as a novel pressure control strategy to minimise pressure violations and leakage under both burst and background leakage conditions. Agents based on asynchronous actor critic (A2C) and recurrent proximal policy optimisation (Recurrent PPO) were trained and compared to benchmarked optimisation algorithms (differential evolution, particle swarm optimisation. A2C manages to minimise leakage by 32.48% under burst conditions and 67.17% under background conditions which was the highest performance in the DRL algorithms. A2C and Recurrent PPO performed well in comparison to the benchmarks with higher processing speed and lower computational effort.

Keywords: deep reinforcement learning, pressure management, water distribution networks, leakage management

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7110 The Generalized Lemaitre-Tolman-Bondi Solutions in Modeling the Cosmological Black Holes

Authors: Elena M. Kopteva, Pavlina Jaluvkova, Zdenek Stuchlik

Abstract:

In spite of the numerous attempts to close the discussion about the influence of cosmological expansion on local gravitationally bounded systems, this question arises in literature again and again and remains still far from its final resolution. Here one of the main problems is the problem of obtaining a physically adequate model of strongly gravitating object immersed in non-static cosmological background. Such objects are usually called ‘cosmological’ black holes and are of great interest in wide set of cosmological and astrophysical areas. In this work the set of new exact solutions of the Einstein equations is derived for the flat space that generalizes the known Lemaitre-Tolman-Bondi solution for the case of nonzero pressure. The solutions obtained are pretending to describe the black hole immersed in nonstatic cosmological background and give a possibility to investigate the hot problems concerning the effects of the cosmological expansion in gravitationally bounded systems, the structure formation in the early universe, black hole thermodynamics and other related problems. It is shown that each of the solutions obtained contains either the Reissner-Nordstrom or the Schwarzschild black hole in the central region of the space. It is demonstrated that the approach of the mass function use in solving of the Einstein equations allows clear physical interpretation of the resulting solutions, that is of much benefit to any their concrete application.

Keywords: exact solutions of the Einstein equations, cosmological black holes, generalized Lemaitre-Tolman-Bondi solutions, nonzero pressure

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7109 Direct Measurement of Pressure and Temperature Variations During High-Speed Friction Experiments

Authors: Simon Guerin-Marthe, Marie Violay

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Thermal Pressurization (TP) has been proposed as a key mechanism involved in the weakening of faults during dynamic ruptures. Theoretical and numerical studies clearly show how frictional heating can lead to an increase in pore fluid pressure due to the rapid slip along faults occurring during earthquakes. In addition, recent laboratory studies have evidenced local pore pressure or local temperature variation during rotary shear tests, which are consistent with TP theoretical and numerical models. The aim of this study is to complement previous ones by measuring both local pore pressure and local temperature variations in the vicinity of a water-saturated calcite gouge layer subjected to a controlled slip velocity in direct double shear configuration. Laboratory investigation of TP process is crucial in order to understand the conditions at which it is likely to become a dominant mechanism controlling dynamic friction. It is also important in order to understand the timing and magnitude of temperature and pore pressure variations, to help understanding when it is negligible, and how it competes with other rather strengthening-mechanisms such as dilatancy, which can occur during rock failure. Here we present unique direct measurements of temperature and pressure variations during high-speed friction experiments under various load point velocities and show the timing of these variations relatively to the slip event.

Keywords: thermal pressurization, double-shear test, high-speed friction, dilatancy

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7108 An Efficient Traceability Mechanism in the Audited Cloud Data Storage

Authors: Ramya P, Lino Abraham Varghese, S. Bose

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By cloud storage services, the data can be stored in the cloud, and can be shared across multiple users. Due to the unexpected hardware/software failures and human errors, which make the data stored in the cloud be lost or corrupted easily it affected the integrity of data in cloud. Some mechanisms have been designed to allow both data owners and public verifiers to efficiently audit cloud data integrity without retrieving the entire data from the cloud server. But public auditing on the integrity of shared data with the existing mechanisms will unavoidably reveal confidential information such as identity of the person, to public verifiers. Here a privacy-preserving mechanism is proposed to support public auditing on shared data stored in the cloud. It uses group signatures to compute verification metadata needed to audit the correctness of shared data. The identity of the signer on each block in shared data is kept confidential from public verifiers, who are easily verifying shared data integrity without retrieving the entire file. But on demand, the signer of the each block is reveal to the owner alone. Group private key is generated once by the owner in the static group, where as in the dynamic group, the group private key is change when the users revoke from the group. When the users leave from the group the already signed blocks are resigned by cloud service provider instead of owner is efficiently handled by efficient proxy re-signature scheme.

Keywords: data integrity, dynamic group, group signature, public auditing

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7107 Applying the Eye Tracking Technique for the Evaluation of Oculomotor System in Patients Survived after Cerebellar Tumors

Authors: Marina Shurupova, Victor Anisimov, Alexander Latanov

Abstract:

Background: The cerebellar lesions inevitably provoke oculomotor impairments in patients of different age. Symptoms of subtentorial tumors, particularly medulloblastomas, include static and dynamic coordination disorders (ataxia, asynergia, imbalance), hypo-muscle tonus, disruption of the cranial nerves, and within the oculomotor system - nystagmus (fine or gross). Subtentorial tumors can also affect the areas of cerebellum that control the oculomotor system. The noninvasive eye-tracking technology allows obtaining multiple oculomotor characteristics such as the number of fixations and their duration, amplitude, latency and velocity of saccades, trajectory and scan path of gaze during the process of the visual field navigation. Eye tracking could be very useful in clinical studies serving as convenient and effective tool for diagnostics. The aim: We studied the dynamics of oculomotor system functioning in patients undergoing remission from cerebellar tumors removal surgeries and following neurocognitive rehabilitation. Methods: 38 children (23 boys, 15 girls, 9-17 years old) that have recovered from the cerebellar tumor-removal surgeries, radiation therapy and chemotherapy and were undergoing course of neurocognitive rehabilitation participated in the study. Two tests were carried out to evaluate oculomotor performance - gaze stability test and counting test. The monocular eye movements were recorded with eye tracker ArringtonResearch (60 Hz). Two experimental sessions with both tests were conducted before and after rehabilitation courses. Results: Within the final session of both tests we observed remarkable improvement in oculomotor performance: 1) in the gaze stability test the spread of gaze positions significantly declined compared to the first session, and 2) the visual path in counting test significantly shortened both compared to the first session. Thus, neurocognitive rehabilitation improved the functioning of the oculomotor system in patients following the cerebellar tumor removal surgeries and subsequent therapy. Conclusions: The experimental data support the effectiveness of the utilization of the eye tracking technique as diagnostic tool in the field of neurooncology.

Keywords: eye tracking, rehabilitation, cerebellar tumors, oculomotor system

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7106 The Relationship between Characteristics of Nurses and Organizational Commitment of Nurses in Geriatric Intermediate Care Facilities in Japan

Authors: Chiharu Miyata, Hidenori Arai

Abstract:

Background: The quality of care in geriatric intermediate facilities (GIFs) in Japan is not in a satisfied level. To improve it, it is crucial to reconsider nurses’ professionalism. Our goal is to create an organizational system that allows nurses to succeed professionally. To do this, we must first discuss the relationship between nurses’ characteristics and the organization. Objectives: The aim of the present study was to determine the extent to which demographic and work-related factors are related to organizational commitment among nurses in GIFs. Method: A quantitative, cross-sectional method was adopted, using a self-completion questionnaire survey. The questionnaires consisted of 49 items for job satisfaction, the three-dimensional commitment model of organizational commitment and the background information of respondents. Results: A total of 1,189 nurses participated. Of those, 91% (n=1084) were women, and mean age was 48.2 years. Most participants were staff nurses (n=791; 66%). Significant differences in 'affective commitment' (AC) scores were found for age (p < .001), overall work experience (p < .001), and work status (p < .001). For work experience in the current facility, significant differences were found in all organizational commitment scores (p < .001). The group with high job satisfaction scored significantly higher in all types of organizational commitment (p < 0.001). Conclusions: These results led to a conclusion that understanding the expectations of nurses at the workplace to adapt with the organization, and creating a work environment that clarifies contents of tasks, especially allowing for nurses to feel significance and achievement with tasks, would increase AC.

Keywords: geriatric intermediate care facilities, geriatric nursing, job satisfaction, organizational commitment

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7105 Unsteady Three-Dimensional Adaptive Spatial-Temporal Multi-Scale Direct Simulation Monte Carlo Solver to Simulate Rarefied Gas Flows in Micro/Nano Devices

Authors: Mirvat Shamseddine, Issam Lakkis

Abstract:

We present an efficient, three-dimensional parallel multi-scale Direct Simulation Monte Carlo (DSMC) algorithm for the simulation of unsteady rarefied gas flows in micro/nanosystems. The algorithm employs a novel spatiotemporal adaptivity scheme. The scheme performs a fully dynamic multi-level grid adaption based on the gradients of flow macro-parameters and an automatic temporal adaptation. The computational domain consists of a hierarchical octree-based Cartesian grid representation of the flow domain and a triangular mesh for the solid object surfaces. The hybrid mesh, combined with the spatiotemporal adaptivity scheme, allows for increased flexibility and efficient data management, rendering the framework suitable for efficient particle-tracing and dynamic grid refinement and coarsening. The parallel algorithm is optimized to run DSMC simulations of strongly unsteady, non-equilibrium flows over multiple cores. The presented method is validated by comparing with benchmark studies and then employed to improve the design of micro-scale hotwire thermal sensors in rarefied gas flows.

Keywords: DSMC, oct-tree hierarchical grid, ray tracing, spatial-temporal adaptivity scheme, unsteady rarefied gas flows

Procedia PDF Downloads 298
7104 Numerical Simulation of Lifeboat Launching Using Overset Meshing

Authors: Alok Khaware, Vinay Kumar Gupta, Jean Noel Pederzani

Abstract:

Lifeboat launching from marine vessel or offshore platform is one of the important areas of research in offshore applications. With the advancement of computational fluid dynamic simulation (CFD) technology to solve fluid induced motions coupled with Six Degree of Freedom (6DOF), rigid body dynamics solver, it is now possible to predict the motion of the lifeboat precisely in different challenging conditions. Traditionally dynamic remeshing approach is used to solve this kind of problems, but remeshing approach has some bottlenecks to control good quality mesh in transient moving mesh cases. In the present study, an overset method with higher-order interpolation is used to simulate a lifeboat launched from an offshore platform into calm water, and volume of fluid (VOF) method is used to track free surface. Overset mesh consists of a set of overlapping component meshes, which allows complex geometries to be meshed with lesser effort. Good quality mesh with local refinement is generated at the beginning of the simulation and stay unchanged throughout the simulation. Overset mesh accuracy depends on the precise interpolation technique; the present study includes a robust and accurate least square interpolation method and results obtained with overset mesh shows good agreement with experiment.

Keywords: computational fluid dynamics, free surface flow, lifeboat launching, overset mesh, volume of fluid

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7103 Corporate Social Responsibility and Financial Performance Complementarity in Multinational Enterprises of the EU and India: A Socio-Political Approach

Authors: Moses Pinto, Ana Paula Monte

Abstract:

The present research analyses the interactions between various categories of corporate social responsibility (CSR) that mediate the relationship between CSR and financial performance in Multinational Enterprises (MNE) in light of the present socio-political factors prevalent in the countries under observation. In the research it has been hypothesized that the absence of consensus in the empirical literature on the CSR–financial performance relationship may be explained by the existence of synergies (Complementarities) between the different CSR components. Upon investigation about whether such relationships exist, a final unbalanced panel sample of 1000 observations taken from 100 Multinational Enterprises per year functioning in the Schengen countries and one south east Asian country namely: India, over the span of 10 years i.e. from the year 2008 to 2018 has been analyzed. The empirical analysis used in the research methodology employs dynamic Panel Data in time series specifically, the system Generalized Method of Moments (GMM) which had been used to detect the varying degrees of relationships between the CSR and financial performance parameters in the background of the socio-political factors prevailing in the countries at the time and also taking into account the bilateral treaty obligations between the countries under observation. The econometric model has employed the financial ratio namely the Return on Assets (ROA) as an indicator of financial performance in order to gauge the internal performance and valuation of a firm as opposed to the Tobin’s Q that provides for the external evaluation of a firm’s financial performance which may not always be accurate. The various CSR dimensions have demonstrated significant correlations to the ‘ROA’ which include some negatively associated correlations and one positively associated correlation that is highly significant throughout the analysis of the observations, namely the correlation between the ‘ROA’ and the CSR dimension: ‘Environment’. The results provide a deeper insight in the synergistic CSR activities that managers could adapt into their Firm’s CSR strategy in order to enhance the ‘ROA’ and also to understand which interactions between the CSR dimensions can be adapted together due to their positively correlated association with each other and the ROA. The future lines of research would be inclined to investigate the effects of socio-political factors on the ROA of the MNEs through better designed econometric models.

Keywords: CSR, financial performance, complementarity, sociopolitical factors

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7102 Assessment and Mitigation of Slope Stability Hazards Along Kombolcha-Desse Road, Northern Ethiopia

Authors: Biruk Wolde Eremacho

Abstract:

The Kombolcha to Desse road, linking Addis Ababa with Northern Ethiopia towns traverses through one of the most difficult mountainous ranges in Ethiopia. The presence of loose unconsolidated materials (colluvium materials), highly weathered and fractured basalt rocks high relief, steep natural slopes, nature of geologic formations exposed along the road section, poor drainage conditions, occurrence of high seasonal rains, and seismically active nature of the region created favorable condition for slope instability in the area. Thus, keeping in mind all above points the present study was conceived to study in detail the slope stability condition of the area. It was realized that detailed slope stability studies along this road section are very necessary to identify critical slopes and to provide the best remedial measures to minimize the slope instability problems which frequently disrupt and endanger the traffic movement on this important road. For the present study based on the field manifestation of instability two most critical slope sections were identified for detailed slope stability analysis. The deterministic slope stability analysis approach was followed to perform the detailed slope stability analysis of the selected slope sections. Factor of safety for the selected slope sections was determined for the different anticipated conditions (i.e., static and dynamic with varied water saturations) using Slope/W and Slide software. Both static and seismic slope stability analysis were carried out and factor of safety was deduced for each anticipated conditions. In general, detailed slope stability analysis of the two critical slope sections reveals that for only static dry condition both the slopes sections would be stable. However, for the rest anticipated conditions defined by static and dynamic situations with varied water saturations both critical slope sections would be unstable. Moreover, the causes of slope instability in the study area are governed by different factors; therefore integrated approaches of remedial measures are more appropriate to mitigate the possible slope instability in the study area. Depending on site condition and slope stability analysis result four types of suitable preventive and remedial measures are recommended namely; proper managements of drainages, retaining structures, gabions, and managing steeply cut slopes.

Keywords: factor of safety, remedial measures, slope stability analysis, static and dynamic condition

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7101 Analyzing the Impact of Migration on HIV and AIDS Incidence Cases in Malaysia

Authors: Ofosuhene O. Apenteng, Noor Azina Ismail

Abstract:

The human immunodeficiency virus (HIV) that causes acquired immune deficiency syndrome (AIDS) remains a global cause of morbidity and mortality. It has caused panic since its emergence. Relationships between migration and HIV/AIDS have become complex. In the absence of prospectively designed studies, dynamic mathematical models that take into account the migration movement which will give very useful information. We have explored the utility of mathematical models in understanding transmission dynamics of HIV and AIDS and in assessing the magnitude of how migration has impact on the disease. The model was calibrated to HIV and AIDS incidence data from Malaysia Ministry of Health from the period of 1986 to 2011 using Bayesian analysis with combination of Markov chain Monte Carlo method (MCMC) approach to estimate the model parameters. From the estimated parameters, the estimated basic reproduction number was 22.5812. The rate at which the susceptible individual moved to HIV compartment has the highest sensitivity value which is more significant as compared to the remaining parameters. Thus, the disease becomes unstable. This is a big concern and not good indicator from the public health point of view since the aim is to stabilize the epidemic at the disease-free equilibrium. However, these results suggest that the government as a policy maker should make further efforts to curb illegal activities performed by migrants. It is shown that our models reflect considerably the dynamic behavior of the HIV/AIDS epidemic in Malaysia and eventually could be used strategically for other countries.

Keywords: epidemic model, reproduction number, HIV, MCMC, parameter estimation

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7100 Research on Energy Field Intervening in Lost Space Renewal Strategy

Authors: Tianyue Wan

Abstract:

Lost space is the space that has not been used for a long time and is in decline, proposed by Roger Trancik. And in his book Finding Lost Space: Theories of Urban Design, the concept of lost space is defined as those anti-traditional spaces that are unpleasant, need to be redesigned, and have no benefit to the environment and users. They have no defined boundaries and do not connect the various landscape elements in a coherent way. With the rapid development of urbanization in China, the blind areas of urban renewal have become a chaotic lost space that is incompatible with the rapid development of urbanization. Therefore, lost space needs to be reconstructed urgently under the background of infill development and reduction planning in China. The formation of lost space is also an invisible division of social hierarchy. This paper tries to break down the social class division and the estrangement between people through the regeneration of lost space. Ultimately, it will enhance vitality, rebuild a sense of belonging, and create a continuous open public space for local people. Based on the concept of lost space and energy field, this paper clarifies the significance of the energy field in the lost space renovation. Then it introduces the energy field into lost space by using the magnetic field in physics as a prototype. The construction of the energy field is support by space theory, spatial morphology analysis theory, public communication theory, urban diversity theory and city image theory. Taking Wuhan’s Lingjiao Park of China as an example, this paper chooses the lost space on the west side of the park as the research object. According to the current situation of this site, the energy intervention strategies are proposed from four aspects: natural ecology, space rights, intangible cultural heritage and infrastructure configuration. And six specific lost space renewal methods are used in this work, including “riveting”, “breakthrough”, “radiation”, “inheritance”, “connection” and “intersection”. After the renovation, space will be re-introduced into the active crow. The integration of activities and space creates a sense of place, improve the walking experience, restores the vitality of the space, and provides a reference for the reconstruction of lost space in the city.

Keywords: dynamic vitality intervention, lost space, space vitality, sense of place

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7099 Dynamic Conformal Arc versus Intensity Modulated Radiotherapy for Image Guided Stereotactic Radiotherapy of Cranial Lesion

Authors: Chor Yi Ng, Christine Kong, Loretta Teo, Stephen Yau, FC Cheung, TL Poon, Francis Lee

Abstract:

Purpose: Dynamic conformal arc (DCA) and intensity modulated radiotherapy (IMRT) are two treatment techniques commonly used for stereotactic radiosurgery/radiotherapy of cranial lesions. IMRT plans usually give better dose conformity while DCA plans have better dose fall off. Rapid dose fall off is preferred for radiotherapy of cranial lesions, but dose conformity is also important. For certain lesions, DCA plans have good conformity, while for some lesions, the conformity is just unacceptable with DCA plans, and IMRT has to be used. The choice between the two may not be apparent until each plan is prepared and dose indices compared. We described a deviation index (DI) which is a measurement of the deviation of the target shape from a sphere, and test its functionality to choose between the two techniques. Method and Materials: From May 2015 to May 2017, our institute has performed stereotactic radiotherapy for 105 patients treating a total of 115 lesions (64 DCA plans and 51 IMRT plans). Patients were treated with the Varian Clinac iX with HDMLC. Brainlab Exactrac system was used for patient setup. Treatment planning was done with Brainlab iPlan RT Dose (Version 4.5.4). DCA plans were found to give better dose fall off in terms of R50% (R50% (DCA) = 4.75 Vs R50% (IMRT) = 5.242) while IMRT plans have better conformity in terms of treatment volume ratio (TVR) (TVR(DCA) = 1.273 Vs TVR(IMRT) = 1.222). Deviation Index (DI) is proposed to better facilitate the choice between the two techniques. DI is the ratio of the volume of a 1 mm shell of the PTV and the volume of a 1 mm shell of a sphere of identical volume. DI will be close to 1 for a near spherical PTV while a large DI will imply a more irregular PTV. To study the functionality of DI, 23 cases were chosen with PTV volume ranged from 1.149 cc to 29.83 cc, and DI ranged from 1.059 to 3.202. For each case, we did a nine field IMRT plan with one pass optimization and a five arc DCA plan. Then the TVR and R50% of each case were compared and correlated with the DI. Results: For the 23 cases, TVRs and R50% of the DCA and IMRT plans were examined. The conformity for IMRT plans are better than DCA plans, with majority of the TVR(DCA)/TVR(IMRT) ratios > 1, values ranging from 0.877 to1.538. While the dose fall off is better for DCA plans, with majority of the R50%(DCA)/ R50%(IMRT) ratios < 1. Their correlations with DI were also studied. A strong positive correlation was found between the ratio of TVRs and DI (correlation coefficient = 0.839), while the correlation between the ratio of R50%s and DI was insignificant (correlation coefficient = -0.190). Conclusion: The results suggest DI can be used as a guide for choosing the planning technique. For DI greater than a certain value, we can expect the conformity for DCA plans to become unacceptably great, and IMRT will be the technique of choice.

Keywords: cranial lesions, dynamic conformal arc, IMRT, image guided radiotherapy, stereotactic radiotherapy

Procedia PDF Downloads 237
7098 A Descriptive Study of Turkish Straits System on Dynamics of Environmental Factors Causing Maritime Accidents

Authors: Gizem Kodak, Alper Unal, Birsen Koldemir, Tayfun Acarer

Abstract:

Turkish Straits System which consists of Istanbul Strait (Bosphorus), Canakkale Strait (Dardanelles) and the Marmara Sea has a strategical location on international maritime as it is a unique waterway between the Mediterranean Sea, Black Sea and the Aegean Sea. Thus, this area has great importance since it is the only waterway between Black Sea countries and the rest of the World. Turkish Straits System has dangerous environmental factors hosts more vessel every day through developing World trade and this situation results in expanding accident risks day by day. Today, a lot of precautions have been taken to ensure safe navigation and to prevent maritime accidents, and international standards are followed to avoid maritime accidents. Despite this, the environmental factors that affect this area, trigger the maritime accidents and threaten the vessels with new accidents risks in different months with different hazards. This descriptive study consists of temporal and spatial analyses of environmental factors causing maritime accidents. This study also aims at contributing to safety navigation including monthly and regionally characteristics of variables. In this context, two different data sets are created consisting of environmental factors and accidents. This descriptive study on the accidents between 2001 and 2017 the mentioned region also studies the months and places of the accidents with environmental factor variables. Environmental factor variables are categorized as dynamic and static factors. Dynamic factors are appointed as meteorological and oceanographical while static factors are appointed as geological factors that threaten safety navigation with geometrical restricts. The variables that form dynamic factors are approached meteorological as wind direction, wind speed, wave altitude and visibility. The circulations and properties of the water mass on the system are studied as oceanographical properties. At the end of the study, the efficient meteorological and oceanographical parameters on the region are presented monthly and regionally. By this way, we acquired the monthly, seasonal and regional distributions of the accidents. Upon the analyses that are done; The Turkish Straits System that connects the Black Sea countries with the other countries and which is one of the most important parts of the world trade; is analyzed on temporal and spatial dimensions on the reasons of the accidents and have been presented as environmental factor dynamics causing maritime accidents.

Keywords: descriptive study, environmental factors, maritime accidents, statistics

Procedia PDF Downloads 197
7097 A Study of Seismic Design Approaches for Steel Sheet Piles: Hydrodynamic Pressures and Reduction Factors Using CFD and Dynamic Calculations

Authors: Helena Pera, Arcadi Sanmartin, Albert Falques, Rafael Rebolo, Xavier Ametller, Heiko Zillgen, Cecile Prum, Boris Even, Eric Kapornyai

Abstract:

Sheet piles system can be an interesting solution when dealing with harbors or quays designs. However, current design methods lead to conservative approaches due to the lack of specific basis of design. For instance, some design features still deal with pseudo-static approaches, although being a dynamic problem. Under this concern, the study particularly focuses on hydrodynamic water pressure definition and stability analysis of sheet pile system under seismic loads. During a seismic event, seawater produces hydrodynamic pressures on structures. Currently, design methods introduce hydrodynamic forces by means of Westergaard formulation and Eurocodes recommendations. They apply constant hydrodynamic pressure on the front sheet pile during the entire earthquake. As a result, the hydrodynamic load may represent 20% of the total forces produced on the sheet pile. Nonetheless, some studies question that approach. Hence, this study assesses the soil-structure-fluid interaction of sheet piles under seismic action in order to evaluate if current design strategies overestimate hydrodynamic pressures. For that purpose, this study performs various simulations by Plaxis 2D, a well-known geotechnical software, and CFD models, which treat fluid dynamic behaviours. Knowing that neither Plaxis nor CFD can resolve a soil-fluid coupled problem, the investigation imposes sheet pile displacements from Plaxis as input data for the CFD model. Then, it provides hydrodynamic pressures under seismic action, which fit theoretical Westergaard pressures if calculated using the acceleration at each moment of the earthquake. Thus, hydrodynamic pressures fluctuate during seismic action instead of remaining constant, as design recommendations propose. Additionally, these findings detect that hydrodynamic pressure contributes a 5% to the total load applied on sheet pile due to its instantaneous nature. These results are in line with other studies that use added masses methods for hydrodynamic pressures. Another important feature in sheet pile design is the assessment of the geotechnical overall stability. It uses pseudo-static analysis since the dynamic analysis cannot provide a safety calculation. Consequently, it estimates the seismic action. One of its relevant factors is the selection of the seismic reduction factor. A huge amount of studies discusses the importance of it but also about all its uncertainties. Moreover, current European standards do not propose a clear statement on that, and they recommend using a reduction factor equal to 1. This leads to conservative requirements when compared with more advanced methods. Under this situation, the study calibrates seismic reduction factor by fitting results from pseudo-static to dynamic analysis. The investigation concludes that pseudo-static analyses could reduce seismic action by 40-50%. These results are in line with some studies from Japanese and European working groups. In addition, it seems suitable to account for the flexibility of the sheet pile-soil system. Nevertheless, the calibrated reduction factor is subjected to particular conditions of each design case. Further research would contribute to specifying recommendations for selecting reduction factor values in the early stages of the design. In conclusion, sheet pile design still has chances for improving its design methodologies and approaches. Consequently, design could propose better seismic solutions thanks to advanced methods such as findings of this study.

Keywords: computational fluid dynamics, hydrodynamic pressures, pseudo-static analysis, quays, seismic design, steel sheet pile

Procedia PDF Downloads 139
7096 Synthetic Optimizing Control of Wind-Wave Hybrid Energy Conversion System

Authors: Lei Xue, Liye Zhao, Jundong Wang, Yu Xue

Abstract:

A hybrid energy conversion system composed of a floating offshore wind turbine (FOWT) and wave energy converters (WECs) may possibly reduce the levelized cost of energy, improving the platform dynamics and increasing the capacity to harvest energy. This paper investigates the aerodynamic performance and dynamic responses of the combined semi-submersible FOWT and point-absorber WECs in frequency and time domains using synthetic optimizing control under turbulent wind and irregular wave conditions. Individual pitch control is applied to the FOWT part, while spring–damping control is used on the WECs part, as well as the synergistic control effect of both are studied. The effect of the above control optimization is analyzed under several typical working conditions, such as below-rated wind speed, rated wind speed, and above-rated wind speed by OpenFAST and WEC-Sim software. Particularly, the wind-wave misalignment is also comparatively investigated, which has demonstrated the importance of applying proper integrated optimal control in this hybrid energy system. More specifically, the combination of individual pitch control and spring–damping control is able to mitigate the platform pitch motion and improve output power. However, the increase in blade root load needs to be considered which needs further investigations in the future.

Keywords: floating offshore wind turbine, wave energy converters, control optimization, individual pitch control, dynamic response

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7095 Changing Trends and Attitudes towards Online Assessment

Authors: Renáta Nagy, Alexandra Csongor, Jon Marquette, Vilmos Warta

Abstract:

The presentation aims at eliciting insight into the results of ongoing research regarding evolving trends and attitudes towards online assessment of English for Medical Purposes. The focus pinpointsonline as one of the most trending formsavailable during the global pandemic. The study was first initiated in 2019 in which its main target was to reveal the intriguing question of students’ and assessors’ attitudes towards online assessment. The research questions the attitudes towards the latest trends, possible online task types, their advantagesand disadvantages through an in-depth experimental process currently undergoing implementation. Material and methods include surveys, needs and wants analysis, and thorough investigations regarding candidates’ and assessors’ attitudes towards online tests in the field of Medicine. The examined test tasks include various online tests drafted in both English and Hungarian by student volunteers at the Medical School of the University of Pécs, Hungary. Over 400 respondents from more than 28 countries participated in the survey, which gives us an international and intercultural insight into how students with different cultural and educational background deal with the evolving online world. The results show the pandemic’s impact, which brought the slumbering online world of assessing roaring alive, fully operational andnowbearsphenomenalrelevancein today’s global education. Undeniably, the results can be used as a perspective in a vast array of contents. The survey hypothesized the generation of the 21st century expect everything readily available online, however, questions whether they are ready for this challenge are lurking in the background.

Keywords: assessment, changes, english, ESP, online assessment, online, trends

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