Search results for: partial order theory
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 18174

Search results for: partial order theory

4404 Assessment of Airtightness Through a Standardized Procedure in a Nearly-Zero Energy Demand House

Authors: Mar Cañada Soriano, Rafael Royo-Pastor, Carolina Aparicio-Fernández, Jose-Luis Vivancos

Abstract:

The lack of insulation, along with the existence of air leakages, constitute a meaningful impact on the energy performance of buildings. Both of them lead to increases in the energy demand through additional heating and/or cooling loads. Additionally, they cause thermal discomfort. In order to quantify these uncontrolled air currents, pressurization and depressurization tests can be performed. Among them, the Blower Door test is a standardized procedure to determine the airtightness of a space which characterizes the rate of air leakages through the envelope surface, calculating to this purpose an air flow rate indicator. In this sense, the low-energy buildings complying with the Passive House design criteria are required to achieve high levels of airtightness. Due to the invisible nature of air leakages, additional tools are often considered to identify where the infiltrations take place. Among them, the infrared thermography entails a valuable technique to this purpose since it enables their detection. The aim of this study is to assess the airtightness of a typical Mediterranean dwelling house located in the Valencian orchad (Spain) restored under the Passive House standard using to this purpose the blower-door test. Moreover, the building energy performance modelling tools TRNSYS (TRaNsient System Simulation program) and TRNFlow (TRaNsient Flow) have been used to determine its energy performance, and the infiltrations’ identification was carried out by means of infrared thermography. The low levels of infiltrations obtained suggest that this house may comply with the Passive House standard.

Keywords: airtightness, blower door, trnflow, infrared thermography

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4403 Synthesis and Characterization of Cellulose-Based Halloysite-Carbon Adsorbent

Authors: Laura Frydel, Piotr M. Slomkiewicz, Beata Szczepanik

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Triclosan has been used as a disinfectant in many medical products, such as: hand disinfectant soaps, creams, mouthwashes, pastes and household cleaners. Due to its strong antimicrobial activity, triclosan is becoming more and more popular and the consumption of disinfectants with triclosan in it is increasing. As a result, this compound increasingly finds its way into waters and soils in an unchanged form, pollutes the environment and may have a negative effect on organisms. The aim of this study was to investigate the synthesis of cellulose-based halloysite-carbon adsorbent and perform its characterization. The template in the halloysite-carbon adsorbent was halloysite nanotubes and the carbon precursor was microcrystalline cellulose. Scanning electron microscope (SEM) images were obtained and the elementary composition (qualitative and quantitative) of the sample was determined by energy dispersion spectroscopy (EDS). The identification of the crystallographic composition of the halloysite nanotubes and the sample of the halloysite-carbon composite was carried out using the X-ray powder diffraction (XRPD) method. The FTIR spectra were acquired before and after the adsorption process in order to determine the functional groups on the adsorbent surface and confirm the interactions between adsorbent and adsorbate molecules. The parameters of the porous structure of the adsorbent, such as the specific surface area (Brunauer-Emmett-Teller method), the total pore volume and the volume of mesopores and micropores were determined. Total carbon and total organic carbon were also determined in the samples. A cellulose-based halloysite-carbon adsorbent was used to remove triclosan from water. The degree of removal of triclosan from water was approximately 90%. The results indicate that the halloysite-carbon composite can be successfully used as an effective adsorbent for removing triclosan from water.

Keywords: Adsorption, cellulose, halloysite, triclosan

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4402 The Social Aspects of Mental Illness among Orthodox Christians of the Tigrinya Ethnic Group in Eritrea

Authors: Erimias Firre

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This study is situated within the religio-cultural milieu of Coptic Orthodox Christians of the Tigrinya ethnic group in Eritrea. With this ethnic group being conservative and traditionally bound, extended family structures dissected along various clans and expansive community networks are the distinguishing mark of its members. Notably, Coptic Tigrinya constitutes the largest percentage of all Christian denominations in Eritrea. As religious, cultural beliefs, rituals and teachings permeate in all aspects of social life, a distinct worldview and traditionalized health and illness conceptualization are common. Accordingly, this study argues that religio-culturally bound illness ideologies immensely determine the perception, help seeking behavior and healing preference of Coptic Tigrinya in Eritrea. The study bears significance in the sense that it bridges an important knowledge gap, given that it is ethno-linguistically (within the Tigrinya ethnic group), spatially (central region of Eritrea) and religiously (Coptic Christianity) specific. The conceptual framework guiding this research centered on the social determinants of mental health, and explores through the lens of critical theory how existing systems generate social vulnerability and structural inequality, providing a platform to reveal how the psychosocial model has the capacity to emancipate and empower those with mental disorders to live productive and meaningful lives. A case study approach was employed to explore the interrelationship between religio-cultural beliefs and practices and perception of common mental disorders of depression, anxiety, bipolar affective, schizophrenia and post-traumatic stress disorders and the impact of these perceptions on people with those mental disorders. Purposive sampling was used to recruit 41 participants representing seven diverse cohorts; people with common mental disorders, family caregivers, general community members, ex-fighters , priests, staff at St. Mary’s and Biet-Mekae Community Health Center; resulting in rich data for thematic analysis. Findings highlighted current religio-cultural perceptions, causes and treatment of mental disorders among Coptic Tigrinya result in widespread labelling, stigma and discrimination, both of those with mental disorders and their families. Traditional healing sources are almost exclusively tried, sometimes for many years, before families and sufferers seek formal medical assessment and treatment, resulting difficult to treat illness chronicity. Service gaps in the formal medical system result in the inability to meet the principles enshrined in the WHO Mental Health Action Plan 2013-2020 to which the Eritrean Government is a signatory. However, the study found that across all participant cohorts, there was a desire for change that will create a culture whereby those with mental disorders will have restored hope, connectedness, healing and self-determination.

Keywords: Coptic Tigrinya, mental disorders, psychosocial model social integration and recovery, traditional healing

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4401 Perceptions of Students toward ODL Services Quality in Facilitating Their Study: Experience of Universitas Terbuka in Managing ODL in Cultural Diversity Areas

Authors: Ribut Alam Malau, Durri Andriani, C. B. Supartomo

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Universitas Terbuka (UT) as a higher education institution implements open and distance education is responsible to provide higher education to all Indonesian citizen wherever they live, including those reside in cultural diversity aras. Operate from Jakarta Head Office and 37 regional centers (ROs), UT is accustomed to the challenge. UT-Kupang and UT-Ambon which oversee East Nusa Tenggara and Maluku have successfully provided quality educational services for students. The two ROs have provided educational facilities which could assist the students to cope with their study in spite of the diversity situations. In order to analyze the effectiveness of the facilities provided, questionnaires focusing on tutorial services were sent to 90 students in the two ROs asking them to assess the facilities which best fulfills students’ needs in terms of their culture diversity. The results showed that UT-Kupang and UT-Ambon have successful in providing education for students in their areas as reflected in more than 80% of respondents aware of the facilities concerning tutorial service except for tutorial mechanism where only 34,5% of respondents aware of. However, despite lower rate of awareness in tutorial mechanism, majority of respondent 90.8% of respondents registered in tutorials and 95.4% will register in tutorials next semester. The majority of respondents showed appreciation for the ROs efforts to provide tutorials on weekdays which could accommodate their beliefs. In addition, conducting tutorials in all islands also perceived highly since students did not have to commute between islands. Efforts done by UT-Kupang and UT-Ambon have proven to be appreciated by students.

Keywords: archipelago, cultural diversity, ODL, service quality, Universitas Terbuka

Procedia PDF Downloads 459
4400 Methodologies for Crack Initiation in Welded Joints Applied to Inspection Planning

Authors: Guang Zou, Kian Banisoleiman, Arturo González

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Crack initiation and propagation threatens structural integrity of welded joints and normally inspections are assigned based on crack propagation models. However, the approach based on crack propagation models may not be applicable for some high-quality welded joints, because the initial flaws in them may be so small that it may take long time for the flaws to develop into a detectable size. This raises a concern regarding the inspection planning of high-quality welded joins, as there is no generally acceptable approach for modeling the whole fatigue process that includes the crack initiation period. In order to address the issue, this paper reviews treatment methods for crack initiation period and initial crack size in crack propagation models applied to inspection planning. Generally, there are four approaches, by: 1) Neglecting the crack initiation period and fitting a probabilistic distribution for initial crack size based on statistical data; 2) Extrapolating the crack propagation stage to a very small fictitious initial crack size, so that the whole fatigue process can be modeled by crack propagation models; 3) Assuming a fixed detectable initial crack size and fitting a probabilistic distribution for crack initiation time based on specimen tests; and, 4) Modeling the crack initiation and propagation stage separately using small crack growth theories and Paris law or similar models. The conclusion is that in view of trade-off between accuracy and computation efforts, calibration of a small fictitious initial crack size to S-N curves is the most efficient approach.

Keywords: crack initiation, fatigue reliability, inspection planning, welded joints

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4399 Optimal Management of Forest Stands under Wind Risk in Czech Republic

Authors: Zohreh Mohammadi, Jan Kaspar, Peter Lohmander, Robert Marusak, Harald Vacik, Ljusk Ola Eriksson

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Storms are important damaging agents in European forest ecosystems. In the latest decades, significant economic losses in European forestry occurred due to storms. This study investigates the problem of optimal harvest planning when forest stands risk to be felled by storms. One of the most applicable mathematical methods which are being used to optimize forest management is stochastic dynamic programming (SDP). This method belongs to the adaptive optimization class. Sequential decisions, such as harvest decisions, can be optimized based on sequential information about events that cannot be perfectly predicted, such as the future storms and the future states of wind protection from other forest stands. In this paper, stochastic dynamic programming is used to maximize the expected present value of the profits from an area consisting of several forest stands. The region of analysis is the Czech Republic. The harvest decisions, in a particular time period, should be simultaneously taken in all neighbor stands. The reason is that different stands protect each other from possible winds. The optimal harvest age of a particular stand is a function of wind speed and different wind protection effects. The optimal harvest age often decreases with wind speed, but it cannot be determined for one stand at a time. When we consider a particular stand, this stand also protects other stands. Furthermore, the particular stand is protected by neighbor stands. In some forest stands, it may even be rational to increase the harvest age under the influence of stronger winds, in order to protect more valuable stands in the neighborhood. It is important to integrate wind risk in forestry decision-making.

Keywords: Czech republic, forest stands, stochastic dynamic programming, wind risk

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4398 Implications on the Training Program for Clinical Psychologists in South Korea

Authors: Chorom Baek, Sungwon Choi

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The purpose of this study is to analyze the supervision system, and the training and continuing education of mental health professionals in USA, UK, Australia (New Zealand), Japan, and so on, and to deduce the implications of Korean mental health service system. In order to accomplish the purpose of this study, following methodologies were adopted: review on the related literatures, statistical data, the related manuals, online materials, and previous studies concerning issues in those countries for the past five years. The training program in Korea was compared with the others’ through this literature analysis. The induced matters were divided with some parts such as training program, continuing education, educational procedure, and curriculum. Based on the analysis, discussion and implications, the conclusion and further suggestion of this study are as follows: First, Korean Clinical Psychology of Association (KCPA) should become more powerful health main training agency for quality control. Second, actual authority of health main training agency should be a grant to training centers. Third, quality control of mental health professionals should be through standardization and systemization of promotion and qualification management. Fourth, education and training about work of supervisors and unification of criteria for supervision should be held. Fifth, the training program for mental health license should be offered by graduate schools. Sixth, legitimated system to protect the right of mental health trainees is needed. Seventh, regularly continuing education after licensed should be compulsory to keep the certification. Eighth, the training program in training centers should meet KCPA requirement. If not, KCPA can cancel the certification of the centers.

Keywords: clinical psychology, Korea, mental health system, training program

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4397 Understanding Mathematics Achievements among U. S. Middle School Students: A Bayesian Multilevel Modeling Analysis with Informative Priors

Authors: Jing Yuan, Hongwei Yang

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This paper aims to understand U.S. middle school students’ mathematics achievements by examining relevant student and school-level predictors. Through a variance component analysis, the study first identifies evidence supporting the use of multilevel modeling. Then, a multilevel analysis is performed under Bayesian statistical inference where prior information is incorporated into the modeling process. During the analysis, independent variables are entered sequentially in the order of theoretical importance to create a hierarchy of models. By evaluating each model using Bayesian fit indices, a best-fit and most parsimonious model is selected where Bayesian statistical inference is performed for the purpose of result interpretation and discussion. The primary dataset for Bayesian modeling is derived from the Program for International Student Assessment (PISA) in 2012 with a secondary PISA dataset from 2003 analyzed under the traditional ordinary least squares method to provide the information needed to specify informative priors for a subset of the model parameters. The dependent variable is a composite measure of mathematics literacy, calculated from an exploratory factor analysis of all five PISA 2012 mathematics achievement plausible values for which multiple evidences are found supporting data unidimensionality. The independent variables include demographics variables and content-specific variables: mathematics efficacy, teacher-student ratio, proportion of girls in the school, etc. Finally, the entire analysis is performed using the MCMCpack and MCMCglmm packages in R.

Keywords: Bayesian multilevel modeling, mathematics education, PISA, multilevel

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4396 High Performance Wood Shear Walls and Dissipative Anchors for Damage Limitation

Authors: Vera Wilden, Benno Hoffmeister, Georgios Balaskas, Lukas Rauber, Burkhard Walter

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Light-weight timber frame elements represent an efficient structural solution for wooden multistory buildings. The wall elements of such buildings – which act as shear diaphragms- provide lateral stiffness and resistance to wind and seismic loads. The tendency towards multi-story structures leads to challenges regarding the prediction of stiffness, strength and ductility of the buildings. Lightweight timber frame elements are built up of several structural parts (sheeting, fasteners, frame, support and anchorages); each of them contributing to the dynamic response of the structure. This contribution describes the experimental and numerical investigation and development of enhanced lightweight timber frame buildings. These developments comprise high-performance timber frame walls with the variable arrangements of sheathing planes and dissipative anchors at the base of the timber buildings, which reduce damages to the timber structure and can be exchanged after significant earthquakes. In order to prove the performance of the developed elements in the context of a real building a full-scale two-story building core was designed and erected in the laboratory and tested experimentally for its seismic performance. The results of the tests and a comparison of the test results to the predicted behavior are presented. Observation during the test also reveals some aspects of the design and details which need to consider in the application of the timber walls in the context of the complete building.

Keywords: dissipative anchoring, full scale test, push-over-test, wood shear walls

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4395 Genomic Identification of Anisakis Simplex Larvae by PCR-RAPD

Authors: Fumiko Kojima, Shuji Fujimoto

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Anisakiasis is a disease caused by infection with an anisakid larvae, mostly Anisakis simplex. The larvae commonly infect in marine fish and the disease is frequently reported in areas of the world where fish is consumed raw, lightly pickled or salted. In Japan, people have the habit of eating raw fish such as ‘sushi’ or ‘sashimi’, so they have more chance of infection with larvae of anisakid nematodes. There are three sibling species in A. simplex larvae, namely, A. simplex sensu stricto (Asss), A. pegreffii (Ap) and A. simplex C. It was revealed that Ap is dominant among the larvae from fish (Scomber japonics) in the Japan Sea side and Asss is dominant among those of the Pacific Ocean side conversely. Although anisakiasis has happened in Japan among both the Japan Sea side area and the Pacific Ocean side area. The aim of this study was to investigate genetic variations between the siblings (Asss and Ap) and within the same sibling species by random amplified polymorphic DNA (RAPD) technique. In order to investigate the genetic difference among the each A. simplex larvae, we used RAPD technique to differentiate individuals of A. simplex obtained from Scomber japonics fish those were caught in the Japan sea (Goto Islands in Nagasaki Prefecture) and the cost of Pacific Ocean (Kanagawa Prefecture). The RAPD patterns of the control DNA (Genus Raphidascaris) were markedly different from those of the A. simplex. There were differences in amplification patterns between Asss and Ap. The RAPD patterns for larvae obtained from fish of the same sea were somewhat different and variations were detected even among larvae from the same fish. These results suggest the considerable high genetic variability between Asss and Ap and the possible existence of genetic variation within the sibling species.

Keywords: Anisakiasis in Japan, Anisakis simplex, genomic identification, PCR-RAPD

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4394 The Documentation of Modernisation Processes in Spain Based on the Residential Architecture of the 1960s. A Patrimonial Perspective on El Plantinar Neighbourhood in Seville

Authors: Julia Rey-Pérez, Julia Díaz Borrego

Abstract:

The modernisation process of the city of Sevilla in Spain and the transformation of the city took place through national and local government initiatives from the 1960s onwards. Part of these actions was the execution of numerous residential neighbourhoodsthat prepared Sevilla for the change of era. This process was possible thanks to the implementation of public policies that showed the imminent need for new architectural programmes, as well as for high-rise architecture built in reinforced concrete. However, very little is known to this day about the modernisation process in Sevilla and the development of these neighbourhoods, which were designed to house a large number of people and are today a key reference point in the Historic Urban Landscape of the city of Seville. Therefore, the present research aims to learn and reflect upon the urban transformation of the city at this time andto deepen the heritage uniqueness of these neighbourhoods, as is the case of ElPlantinarneighbourhood.The methodology proposed for this research is structured in three phases, where in the first stage, a general study of the El Plantinarneighbourhood was carried out on three scales: urban, object-typological and perceptive. In the second stage, the cultural attributes and values of the urban complex in question were identified in order to determine whether the case study is truly representative of the beginnings of modernity in Spain and whether it needs a heritage approach. Finally, a third phase is proposed in which criteria will be defined on how to intervene in this neighbourhood to guarantee its presence in the urban landscape of the city of Seville. The expected results will help to understand the process of modernisation that the city has undergone, as well as the heritage value of this architecture in the construction of the collective memory.

Keywords: modern heritage, urban obsolescence, methodology, develop

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4393 Hybrid Recovery of Copper and Silver from Photovoltaic Ribbon and Ag finger of End-Of-Life Solar Panels

Authors: T. Patcharawit, C. Kansomket, N. Wongnaree, W. Kritsrikan, T. Yingnakorn, S. Khumkoa

Abstract:

Recovery of pure copper and silver from end-of-life photovoltaic panels was investigated in this paper using an effective hybrid pyro-hydrometallurgical process. In the first step of waste treatment, solar panel waste was first dismantled to obtain a PV sheet to be cut and calcined at 500°C, to separate out PV ribbon from glass cullet, ash, and volatile while the silicon wafer containing silver finger was collected for recovery. In the second step of metal recovery, copper recovery from photovoltaic ribbon was via 1-3 M HCl leaching with SnCl₂ and H₂O₂ additions in order to remove the tin-lead coating on the ribbon. The leached copper band was cleaned and subsequently melted as an anode for the next step of electrorefining. Stainless steel was set as the cathode with CuSO₄ as an electrolyte, and at a potential of 0.2 V, high purity copper of 99.93% was obtained at 96.11% recovery after 24 hours. For silver recovery, the silicon wafer containing silver finger was leached using HNO₃ at 1-4 M in an ultrasonic bath. In the next step of precipitation, silver chloride was then obtained and subsequently reduced by sucrose and NaOH to give silver powder prior to oxy-acetylene melting to finally obtain pure silver metal. The integrated recycling process is considered to be economical, providing effective recovery of high purity metals such as copper and silver while other materials such as aluminum, copper wire, glass cullet can also be recovered to be reused commercially. Compounds such as PbCl₂ and SnO₂ obtained can also be recovered to enter the market.

Keywords: electrorefining, leaching, calcination, PV ribbon, silver finger, solar panel

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4392 Characteristing Aquifer Layers of Karstic Springs in Nahavand Plain Using Geoelectrical and Electromagnetic Methods

Authors: A. Taheri Tizro, Rojin Fasihi

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Geoelectrical method is one of the most effective tools in determining subsurface lithological layers. The electromagnetic method is also a newer method that can play an important role in determining and separating subsurface layers with acceptable accuracy. In the present research, 10 electromagnetic soundings were collected in the upstream of 5 karstic springs of Famaseb, Faresban, Ghale Baroodab, Gian and Gonbad kabood in Nahavand plain of Hamadan province. By using the emerging data, the belectromagnetic logs were prepared at different depths and compared with 5 logs of the geoelectric method. The comparison showed that the value of NRMSE in the geoelectric method for the 5 springs of Famaseb, Faresban, Ghale Baroodab, Gian and Gonbad kabood were 7.11, 7.50, respectively. It is 44.93, 3.99, and 2.99, and in the electromagnetic method, the value of this coefficient for the investigated springs is about 1.4, 1.1, 1.2, 1.5, and 1.3, respectively. In addition to the similarity of the results of the two methods, it is found that, the accuracy of the electromagnetic method based on the NRMSE value is higher than the geoelectric method. The advantage of the electromagnetic method compared to geoelectric is on less time consuming and its cost prohibitive. The depth to water table is the final result of this research work , which showed that in the springs of Famaseb, Faresban, Ghale Baroodab, Gian and Gonbad kabood, having depth of about 6, 20, 10, 2 36 meters respectively. The maximum thickness of the aquifer layer was estimated in Gonbad kabood spring (36 meters) and the lowest in Gian spring (2 meters). These results can be used to identify the water potential of the region in order to better manage water resources.

Keywords: karst spring, geoelectric, aquifer layers, nahavand

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4391 Urban Transport Demand Management Multi-Criteria Decision Using AHP and SERVQUAL Models: Case Study of Nigerian Cities

Authors: Suleiman Hassan Otuoze, Dexter Vernon Lloyd Hunt, Ian Jefferson

Abstract:

Urbanization has continued to widen the gap between demand and resources available to provide resilient and sustainable transport services in many fast-growing developing countries' cities. Transport demand management is a decision-based optimization concept for both benchmarking and ensuring efficient use of transport resources. This study assesses the service quality of infrastructure and mobility services in the Nigerian cities of Kano and Lagos through five dimensions of quality (i.e., Tangibility, Reliability, Responsibility, Safety Assurance and Empathy). The methodology adopts a hybrid AHP-SERVQUAL model applied on questionnaire surveys to gauge the quality of satisfaction and the views of experts in the field. The AHP results prioritize tangibility, which defines the state of transportation infrastructure and services in terms of satisfaction qualities and intervention decision weights in the two cities. The results recorded ‘unsatisfactory’ indices of quality of performance and satisfaction rating values of 48% and 49% for Kano and Lagos, respectively. The satisfaction indices are identified as indicators of low performances of transportation demand management (TDM) measures and the necessity to re-order priorities and take proactive steps towards infrastructure. The findings pilot a framework for comparative assessment of recognizable standards in transport services, best ethics of management and a necessity of quality infrastructure to guarantee both resilient and sustainable urban mobility.

Keywords: transportation demand management, multi-criteria decision support, transport infrastructure, service quality, sustainable transport

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4390 Osteogenesis in Thermo-Sensitive Hydrogel Using Mesenchymal Stem Cell Derived from Human Turbinate

Authors: A. Reum Son, Jin Seon Kwon, Seung Hun Park, Hai Bang Lee, Moon Suk Kim

Abstract:

These days, stem cell therapy is focused on for promising source of treatment in clinical human disease. As a supporter of stem cells, in situ-forming hydrogels with growth factors and cells appear to be a promising approach in tissue engineering. To examine osteogenic differentiation of hTMSCs which is one of mesenchymal stem cells in vivo in an injectable hydrogel, we use a methoxy polyethylene glycol-polycaprolactone blockcopolymer (MPEG-PCL) solution with osteogenic factors. We synthesized MPEG-PCL hydrogel and measured viscosity to check sol-gel transition. In order to demonstrate osteogenic ability of hTMSCs, we conducted in vitro osteogenesis experiment. Then, to confirm the cell cytotoxicity, we performed WST-1 with hTMSCs and MPEG-PCL. As the result of in vitro experiment, we implanted cell and hydrogel mixture into animal model and checked degree of osteogenesis with histological analysis and amount of expression genes. Through these experimental data, MPEG-PCL hydrogel has sol-gel transition in temperature change and is biocompatible with stem cells. In histological analysis and gene expression, hTMSCs are very good source of osteogenesis with hydrogel and will use it to tissue engineering as important treatment method. hTMSCs could be a good adult stem cell source for usability of isolation and high proliferation. When hTMSCs are used as cell therapy method with in situ-formed hydrogel, they may provide various benefits like a noninvasive alternative for bone tissue engineering applications.

Keywords: injectable hydrogel, stem cell, osteogenic differentiation, tissue engineering

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4389 Effects of Whole-Body Vibration Training on Fibrinolytic and Coagulative Factors in Healthy Young Man

Authors: Farshad Ghazalian, Seyed Hossein Alavi

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Background: Use of whole body vibration (WBV) as an exercise method has rapidly increased over the last decade. The aim of this study was to evaluate effects of five week whole-body vibration training with different amplitudes and progressive frequencies on fibrinolytic and coagulative factors. Methods: Twenty five healthy male students were divided randomly in three groups: high amplitude vibration group (n=10), low amplitude vibration group (n=10), and control group (n=5). The vibration training consisted of 5 week whole-body vibration 3 times a week with amplitudes 4 and 2 mm and progressive frequencies from 25Hz with increments of 5Hz weekly. Concentrations of fibrinogen, plasminogen, tPA, and PAI-1 before and after 5 weeks of training were measured in plasma samples. Statistical analysis was done using one way analysis of variance. In order to compare pre-test with post test we used Wilcoxon signed ranked test .P<0.05 was considered statistically significant. Results: The 5 week high amplitude vibration training caused a significant improvement in tissue plasminogen activator (tPA) (p=0.028), and PAI-1 (p=0.033), fibrinogen showed decrease albeit not significantly (p=0.052). Plasminogen showed decrease not significantly (p=0.508). Low-amplitude vibration training caused a significant improvement in tissue plasminogen activator (tPA) (p=0.006) and and PAI-1 showed decrease not significantly (p=0.907). Fibrinogen showed decrease albeit not significantly (p=0.19). Plasminogen showed decrease not significantly (p=0.095). However, between groups there was no significant effect on tissue plasminogen activator (tPA) (p = 0.50), PAI-1 (p=0.249), Plasminogen (p=0.742), and fibrinogen (p=0.299). Conclusion: Amplitude of vibrations training is a important variable that effect on fibrino lytic factors.

Keywords: vibration, fibrinolysis, blood coagulation, plasminogen

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4388 Metallurgy of Friction Welding of Porous Stainless Steel-Solid Iron Billets

Authors: S. D. El Wakil

Abstract:

The research work reported here was aimed at investigating the feasibility of joining high-porosity stainless steel discs and wrought iron bars by friction welding. The sound friction-welded joints were then subjected to a metallurgical investigation and an analysis of failure resulting from tensile loading. Discs having 50 mm diameter and 10 mm thickness were produced by loose sintering of stainless steel powder at a temperature of 1350 oC in an argon atmosphere for one hour. Minor machining was then carried out to control the dimensions of the discs, and the density of each disc could then be determined. The level of porosity was calculated and was found to be about 40% in all of those discs. Solid wrought iron bars were also machined to facilitate tensile testing of the joints produced by friction welding. Using our previously gained experience, the porous stainless steel disc and the wrought iron tube were successfully friction welded. SEM was employed to examine the fracture surface after a tensile test of the joint in order to determine the type of failure. It revealed that the failure did not occur in the joint, but rather in the in the porous metal in the area adjacent to the joint. The load carrying capacity was actually determined by the strength of the porous metal and not by that of the welded joint. Macroscopic and microscopic metallographic examinations were also performed and showed that the welded joint involved a dense heat-affected zone where the porous metal underwent densification at elevated temperature, explaining and supporting the findings of the SEM study.

Keywords: fracture of friction-welded joints, metallurgy of friction welding, solid-porous structures, strength of joints

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4387 Impacts and Management of Oil Spill Pollution along the Chabahar Bay by ESI Mapping, Iran

Authors: M. Sanjarani, A. Danehkar, A. Mashincheyan, A. H. Javid, S. M. R. Fatemi

Abstract:

The oil spill in marine water has direct impact on coastal resources and community. Environmental Sensitivity Index (ESI) map is the first step to assess the potential impact of an oil spill and minimize the damage of coastal resources. In order to create Environmental Sensitivity Maps for the Chabahar bay (Iran), information has been collected in three different layers (Shoreline Classification, Biological and Human- uses resources) by means of field observations and measurements of beach morphology, personal interviews with professionals of different areas and the collection of bibliographic information. In this paper an attempt made to prepare an ESI map for sensitivity to oil spills of Chabahar bay coast. The Chabahar bay is subjected to high threaten to oil spill because of port, dense mangrove forest,only coral spot in Oman Sea and many industrial activities. Mapping the coastal resources, shoreline and coastal structures was carried out using Satellite images and GIS technology. The coastal features classified into three major categories as: Shoreline Classification, Biological and Human uses resources. The important resources classified into mangrove, Exposed tidal flats, sandy beach, etc. The sensitivity of shore was ranked as low to high (1 = low sensitivity,10 = high sensitivity) based on geomorphology of Chabahar bay coast using NOAA standards (sensitivity to oil, ease of clean up, etc). Eight ESI types were found in the area namely; ESI 1A, 1C, 3A, 6B, 7, 8B,9A and 10D. Therefore, in the study area, 50% were defined as High sensitivity, less than 1% as Medium, and 49% as low sensitivity areas. The ESI maps are useful to the oil spill responders, coastal managers and contingency planners. The overall ESI mapping product can provide a valuable management tool not only for oil spill response but for better integrated coastal zone management.

Keywords: ESI, oil spill, GIS, Chabahar Bay, Iran

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4386 Simplified Stress Gradient Method for Stress-Intensity Factor Determination

Authors: Jeries J. Abou-Hanna

Abstract:

Several techniques exist for determining stress-intensity factors in linear elastic fracture mechanics analysis. These techniques are based on analytical, numerical, and empirical approaches that have been well documented in literature and engineering handbooks. However, not all techniques share the same merit. In addition to overly-conservative results, the numerical methods that require extensive computational effort, and those requiring copious user parameters hinder practicing engineers from efficiently evaluating stress-intensity factors. This paper investigates the prospects of reducing the complexity and required variables to determine stress-intensity factors through the utilization of the stress gradient and a weighting function. The heart of this work resides in the understanding that fracture emanating from stress concentration locations cannot be explained by a single maximum stress value approach, but requires use of a critical volume in which the crack exists. In order to understand the effectiveness of this technique, this study investigated components of different notch geometry and varying levels of stress gradients. Two forms of weighting functions were employed to determine stress-intensity factors and results were compared to analytical exact methods. The results indicated that the “exponential” weighting function was superior to the “absolute” weighting function. An error band +/- 10% was met for cases ranging from a steep stress gradient in a sharp v-notch to the less severe stress transitions of a large circular notch. The incorporation of the proposed method has shown to be a worthwhile consideration.

Keywords: fracture mechanics, finite element method, stress intensity factor, stress gradient

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4385 Investor Psychology, Housing Prices, and Stock Market Response to Policy Decisions During the Covid-19 Recession in the United States

Authors: Ly Nguyen, Vidit Munshi

Abstract:

During the Covid-19 recession, the United States government has implemented several instruments to mitigate the impacts and revitalize the economy. This paper explores the effects of the various government policy decisions on stock returns, housing prices, and investor psychology during the pandemic in the United States. A numerous previous literature studies on this subject, yet very few focus on the context similar to what we are currently experiencing. Our monthly data covering the period from January 2019 through July 2021 were collected from Datastream. Utilizing the VAR model, we document a dynamic relationship between the market and policy actions throughout the period. In particular, the movements of Unemployment, Stock returns, and Housing prices are strongly sensitive to changes in government policies. Our results also indicate that changes in production level, stock returns, and interest rates decisions influence how investors perceived future market risk and expectations. We do not find any significant nexus between monetary and fiscal policy. Our findings imply that information on government policy and stock market performance provide useful feedback to one another in order to make better decisions in the current and future pandemic. Understanding how the market responds to a shift in government practices has important implications for authorities in implementing policy to avoid assets bubbles and market overreactions. The paper also provides useful implications for investors in evaluating the effectiveness of different policies and diversifying portfolios to minimize systematic risk and maximize returns.

Keywords: Covid-19 recession, United States, government policies, investor psychology, housing prices, stock market returns

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4384 Self-Healing Phenomenon Evaluation in Cementitious Matrix with Different Water/Cement Ratios and Crack Opening Age

Authors: V. G. Cappellesso, D. M. G. da Silva, J. A. Arndt, N. dos Santos Petry, A. B. Masuero, D. C. C. Dal Molin

Abstract:

Concrete elements are subject to cracking, which can be an access point for deleterious agents that can trigger pathological manifestations reducing the service life of these structures. Finding ways to minimize or eliminate the effects of this aggressive agents’ penetration, such as the sealing of these cracks, is a manner of contributing to the durability of these structures. The cementitious self-healing phenomenon can be classified in two different processes. The autogenous self-healing that can be defined as a natural process in which the sealing of this cracks occurs without the stimulation of external agents, meaning, without different materials being added to the mixture, while on the other hand, the autonomous seal-healing phenomenon depends on the insertion of a specific engineered material added to the cement matrix in order to promote its recovery. This work aims to evaluate the autogenous self-healing of concretes produced with different water/cement ratios and exposed to wet/dry cycles, considering two ages of crack openings, 3 days and 28 days. The self-healing phenomenon was evaluated using two techniques: crack healing measurement using ultrasonic waves and image analysis performed with an optical microscope. It is possible to observe that by both methods, it possible to observe the self-healing phenomenon of the cracks. For young ages of crack openings and lower water/cement ratios, the self-healing capacity is higher when compared to advanced ages of crack openings and higher water/cement ratios. Regardless of the crack opening age, these concretes were found to stabilize the self-healing processes after 80 days or 90 days.

Keywords: sealf-healing, autogenous, water/cement ratio, curing cycles, test methods

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4383 Influence of Physicochemical Water Quality Parameters on Abundance of Aquatic Insects in Rivers of Perak, Malaysia

Authors: Nur Atirah Hasmi, Nadia Nisha Musa, Hasnun Nita Ismail, Zulfadli Mahfodz

Abstract:

The effect of water quality parameters on the abundance of aquatic insects has been studied in Batu Berangkai, Dipang, Kuala Woh and Lata Kinjang Rivers, Perak, northern peninsular Malaysia. The focuses are to compare the abundance of aquatic insects in each sampling areas and to investigate the physical and chemical factors (water temperature, depth of water, canopy, water velocity, pH value, and dissolved oxygen) on the abundance of aquatic insects. The samples and data were collected by using aquatic net and multi-probe parameter. Physical parameters; water velocity, water temperature, depth, canopy cover, and two chemical parameters; pH value and dissolved oxygen have been measured in situ and recorded. A total of 631 individuals classified into 6 orders and 18 families of aquatic insects were identified from four sampling sites. The largest percentage of samples collected is from order Plecoptera 35.8%, followed by Ephemeroptera 32.6%, Trichoptera 17.0%, Hemiptera 8.1%, Coleoptera 4.8%, and the least is Odonata 1.7%. The aquatic insects collected from Dipang River have the highest abundance of 273 individuals from 6 orders and 13 families and the least insects trapped at Lata Kinjang which only have 64 individuals from 5 orders and 6 families. There is significant association between different sampling areas and abundance of aquatic insects (p<0.05). High abundance of aquatic insects was found in higher water temperature, low water velocity, deeper water, low pH, high amount of dissolved oxygen, and the area that is not covered by canopy.

Keywords: aquatic insect, physicochemical parameter, river, water quality

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4382 Reliability Based Analysis of Multi-Lane Reinforced Concrete Slab Bridges

Authors: Ali Mahmoud, Shadi Najjar, Mounir Mabsout, Kassim Tarhini

Abstract:

Empirical expressions for estimating the wheel load distribution and live-load bending moment are typically specified in highway bridge codes such as the AASHTO procedures. The purpose of this paper is to analyze the reliability levels that are inherent in reinforced concrete slab bridges that are designed based on the simplified empirical live load equations in the AASHTO LRFD procedures. To achieve this objective, bridges with multi-lanes (three and four lanes) and different spans are modeled using finite-element analysis (FEA) subjected to HS20 truck loading, tandem loading, and standard lane loading per AASHTO LRFD procedures. The FEA results are compared with the AASHTO LRFD moments in order to quantify the biases that might result from the simplifying assumptions adopted in AASHTO. A reliability analysis is conducted to quantify the reliability index for bridges designed using AASHTO procedures. To reach a consistent level of safety for three- and four-lane bridges, following a previous study restricted to one- and two-lane bridges, the live load factor in the design equation proposed by AASHTO LRFD will be assessed and revised if needed by alternating the live load factor for these lanes. The results will provide structural engineers with more consistent provisions to design concrete slab bridges or evaluate the load-carrying capacity of existing bridges.

Keywords: reliability analysis of concrete bridges, finite element modeling, reliability analysis, reinforced concrete bridge design, load carrying capacity

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4381 Optimization Technique for the Contractor’s Portfolio in the Bidding Process

Authors: Taha Anjamrooz, Sareh Rajabi, Salwa Bheiry

Abstract:

Selection between the available projects in bidding processes for the contractor is one of the essential areas to concentrate on. It is important for the contractor to choose the right projects within its portfolio during the tendering stage based on certain criteria. It should align the bidding process with its origination strategies and goals as a screening process to have the right portfolio pool to start with. Secondly, it should set the proper framework and use a suitable technique in order to optimize its selection process for concertation purpose and higher efforts during the tender stage with goals of success and winning. In this research paper, a two steps framework proposed to increase the efficiency of the contractor’s bidding process and the winning chance of getting the new projects awarded. In this framework, initially, all the projects pass through the first stage screening process, in which the portfolio basket will be evaluated and adjusted in accordance with the organization strategies to the reduced version of the portfolio pool, which is in line with organization activities. In the second stage, the contractor uses linear programming to optimize the portfolio pool based on available resources such as manpower, light equipment, heavy equipment, financial capability, return on investment, and success rate of winning the bid. Therefore, this optimization model will assist the contractor in utilizing its internal resource to its maximum and increase its winning chance for the new project considering past experience with clients, built-relation between two parties, and complexity in the exertion of the projects. The objective of this research will be to increase the contractor's winning chance in the bidding process based on the success rate and expected return on investment.

Keywords: bidding process, internal resources, optimization, contracting portfolio management

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4380 Under-Reporting and Under-Recording of Hate Crimes against Muslim Women in Italy

Authors: Broccolo Cinzia, Grigaliunaite Ruta, Saint-Nom Cloé, Savasta Guido

Abstract:

The present article analyses the root causes of under-reporting and under-recording of hate crimes against Muslim women in Italy. The main findings emerged from the survey conducted between May and September 2022 within the framework of the TRUST project (co-funded by the CERV programme (CERV-2021-EQUAL) of the European Union) with relevant practitioners and members of the Muslim community, including first-generation and second-generation Muslim women residing in Italy. The findings reveal that multiple factors contribute to the low reporting rate as well as to the flaws in recording episodes of intolerance and hatred against the above-mentioned group. Lack of trust in the judiciary or the police may represent one of the main causes of under-reporting; however, the phenomenon is not limited to such aspects, and additional factors and sources of discrimination paving the way to under-recording have been identified during the survey. The significant “tendency” to not report a case of intolerance as the difficulties in identifying the discriminatory nature of the crime are two faces of the same coin and are particularly intertwined; despite this, at first, both issues need to be assessed and analysed separately in order to take their own specificities into duly consideration. By contrast, the potential solution to low recording and reporting trends should be found collectively, namely by involving all the relevant parties and bodies facing the above-mentioned issues. In this regard, a participatory and multi-agency approach may curb the root causes leading Muslim women not to report and, besides this, support law enforcement officials as well as public authorities in providing a more effective service to the victims of hatred, whether offline or online.

Keywords: hate crime, under-reporting, under-recording, Islamophobia, Muslim women

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4379 Molecular Simulation of NO, NH3 Adsorption in MFI and H-ZSM5

Authors: Z. Jamalzadeh, A. Niaei, H. Erfannia, S. G. Hosseini, A. S. Razmgir

Abstract:

Due to developing the industries, the emission of pollutants such as NOx, SOx, and CO2 are rapidly increased. Generally, NOx is attributed to the mono nitrogen oxides of NO and NO2 that is one of the most important atmospheric contaminants. Hence, controlling the emission of nitrogen oxides is urgent environmentally. Selective Catalytic Reduction of NOx is one of the most common techniques for NOx removal in which Zeolites have wide application due to their high performance. In zeolitic processes, the catalytic reaction occurs mostly in the pores. Therefore, investigation the adsorption phenomena of the molecules in order to gain an insight and understand the catalytic cycle is of important. Hence, in current study, molecular simulations is applied for studying the adsorption phenomena in nanocatalysts applied for SCR of NOx process. The effect of cation addition to the support in the catalysts’ behavior through adsorption step was explored by Mont Carlo (MC). Simulation time of 1 Ns accompanying 1 fs time step, COMPASS27 Force Field and the cut off radios of 12.5 Ȧ was applied for performed runs. It was observed that the adsorption capacity increases in the presence of cations. The sorption isotherms demonstrated the behavior of type I isotherm categories and sorption capacity diminished with increase in temperature whereas an increase was observed at high pressures. Besides, NO sorption showed higher sorption capacity than NH3 in H–ZSM5. In this respect, the Energy distributions signified that the molecules could adsorb in just one sorption site at the catalyst and the sorption energy of NO was stronger than the NH3 in H-ZSM5. Furthermore, the isosteric heat of sorption data showed nearly same values for the molecules; however, it indicated stronger interactions of NO molecules with H-ZSM5 Zeolite compared to the isosteric heat of NH3 which was low in value.

Keywords: Monte Carlo simulation, adsorption, NOx, ZSM5

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4378 Preventing Neurodegenerative Diseases by Stabilization of Superoxide Dismutase by Natural Polyphenolic Compounds

Authors: Danish Idrees, Vijay Kumar, Samudrala Gourinath

Abstract:

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease caused by misfolding and aggregation of Cu, Zn superoxide dismutase (SOD1). The use of small molecules has been shown to stabilize the SOD1 dimer and preventing its dissociation and aggregation. In this study, we employed molecular docking, molecular dynamics simulation and surface plasmon resonance (SPR) to study the interactions between SOD1 and natural polyphenolic compounds. In order to explore the noncovalent interaction between SOD1 and natural polyphenolic compounds, molecular docking and molecular dynamic (MD) simulations were employed to gain insights into the binding modes and free energies of SOD1-polyphenolic compounds. MM/PBSA methods were used to calculate free energies from obtained MD trajectories. The compounds, Hesperidin, Ergosterol, and Rutin showed the excellent binding affinity in micromolar range with SOD1. Ergosterol and Hesperidin have the strongest binding affinity to SOD1 and was subjected to further characterization. Biophysical experiments using Circular Dichroism and Thioflavin T fluorescence spectroscopy results show that the binding of these two compounds can stabilize SOD1 dimer and inhibit the aggregation of SOD1. Molecular simulation results also suggest that these compounds reduce the dissociation of SOD1 dimers through direct interaction with the dimer interface. This study will be helpful to develop other drug-like molecules which may have the effect to reduce the aggregation of SOD1.

Keywords: amyotrophic lateral sclerosis, molecular dynamics simulation, surface plasmon resonance, superoxide dismutase

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4377 Evaluating the Effects of an Educational Video on Running Shoe Selection and Subjective Perceptions

Authors: Andrew Fife, Jean-Francois Esculier, Codi Ramsey, Kim Hebert-Losier

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Objectives: We aimed to identify how an evidence-based educational video influences how runners select shoes, and perceive shoe comfort, satisfaction, and performance over three months in comparison with a control video. Design: Two groups participated in a double-blind randomised controlled trial. Method: Fifty-six runners were randomly assigned to view one of two video presentations prior to purchasing new shoes for road running in speciality stores. Runners completed a survey with regards to their own shoes and one in reference to the new shoes purchased at three timepoints: before first use, onemonth post-purchase, and three-months post-purchase. Perceived shoe comfort, satisfaction, and performance were assessed using 100 mm visual analogue scales. Factors that influenced their shoe purchase were ranked in order of importance. Results: Comfort and satisfaction were not significantly different between groups and timepoints. The perceived performance of new shoes (75.6 mm) was significantly greater than own shoes (mean: 67.6 mm) before first use, but ratings returned to own-shoe levels one month later in both groups. The group receiving the evidence-based presentation reported their purchased shoes as being influenced more by the video (55.4 mm) than the control group (21.8 mm), although both chose the same brand and model as previously worn over half of the time. Runners in both groups prioritised fit, comfort, and choosing similar shoes to the ones they previously used. Conclusions: In contrast to expectations, the evidence-based educational video did not appear to influence running shoe selection, or overall perceived shoe comfort, satisfaction, or performance.

Keywords: comfort, consumer behaviour, consciousness, education, running, shoes

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4376 Synaesthetic Metaphors in Persian: a Cognitive Corpus Based and Comparative Perspective

Authors: A. Afrashi

Abstract:

Introduction: Synaesthesia is a term denoting the perception or description of the perception of one sense modality in terms of another. In literature, synaesthesia refers to a technique adopted by writers to present ideas, characters or places in such a manner that they appeal to more than one sense like hearing, seeing, smell etc. at a given time. In everyday language too we find many examples of synaesthesia. We commonly hear phrases like ‘loud colors’, ‘frozen silence’ and ‘warm colors’, ‘bitter cold’ etc. Empirical cognitive studies have proved that synaesthetic representations both in literature and everyday languages are constrained ie. they do not map randomly among sensory domains. From the beginning of the 20th century Synaesthesia has been a research domain both in literature and structural linguistics. However the exploration of cognitive mechanisms motivating synaesthesia, have made it an important topic in 21st century cognitive linguistics and literary studies. Synaesthetic metaphors are linguistic representations of those mental mechanisms, the study of which reveals invaluable facts about perception, cognition and conceptualization. According to the main tenets of cognitive approach to language and literature, unified and similar cognitive mechanisms are active both in everyday language and literature, and synaesthesia is one of those cognitive mechanisms. Main objective of the present research is to answer the following questions: What types of sense transfers are accessible in Persian synaesthetic metaphors. How are these types of sense transfers cognitively explained. What are the results of cross-linguistic comparative study of synaestetic metaphors based on the existing observations? Methodology: The present research employs a cognitive - corpus based method, and the theoretical framework adopted to analyze linguistic synaesthesia is the contemporary theory of metaphor, where conceptual metaphor is the result of systemic mappings across cognitive domains. Persian Language Data- base (PLDB) in the Institute for Humanities and Cultural Studies which consists mainly of Persian modern prose, is searched for synaesthetic metaphors. Then for each metaphorical structure, the source and target domains are determined. Then sense transfers are identified and the types of synaesthetic metaphors recognized. Findings: Persian synaesthetic metaphors conform to the hierarchical distribution principle, according to which transfers tend to go from touch to taste to smell to sound and to sight, not vice versa. In other words mapping from more accessible or basic concepts onto less accessible or less basic ones seems more natural. Furthermore the most frequent target domain in Persian synaesthetic metaphors is sound. Certain characteristics of Persian synaesthetic metaphors are comparable with existing related researches carried on English, French, Hungarian and Chinese synaesthetic metaphors. Conclusion: Cognitive corpus based approaches to linguistic synaesthesia, are applicable to stylistics and literary criticism and this recent research domain is an efficient approach to study cross linguistic variations to find out which of the five senses is dominant cross linguistically and cross culturally as the target domain in metaphorical mappings , and so forth receiving dominance in conceptualizations.

Keywords: cognitive semantics, conceptual metaphor, synaesthesia, corpus based approach

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4375 Harmonic Distortion Analysis in Low Voltage Grid with Grid-Connected Photovoltaic

Authors: Hedi Dghim, Ahmed El-Naggar, Istvan Erlich

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Power electronic converters are being introduced in low voltage (LV) grids at an increasingly rapid rate due to the growing adoption of power electronic-based home appliances in residential grid. Photovoltaic (PV) systems are considered one of the potential installed renewable energy sources in distribution power systems. This trend has led to high distortion in the supply voltage which consequently produces harmonic currents in the network and causes an inherent voltage unbalance. In order to investigate the effect of harmonic distortions, a case study of a typical LV grid configuration with high penetration of 3-phase and 1-phase rooftop mounted PV from southern Germany was first considered. Electromagnetic transient (EMT) simulations were then carried out under the MATLAB/Simulink environment which contain detailed models for power electronic-based loads, ohmic-based loads as well as 1- and 3-phase PV. Note that, the switching patterns of the power electronic circuits were considered in this study. Measurements were eventually performed to analyze the distortion levels when PV operating under different solar irradiance. The characteristics of the load-side harmonic impedances were analyzed, and their harmonic contributions were evaluated for different distortion levels. The effect of the high penetration of PV on the harmonic distortion of both positive and negative sequences was also investigated. The simulation results are presented based on case studies. The current distortion levels are in agreement with relevant standards, otherwise the Total Harmonic Distortion (THD) increases under low PV power generation due to its inverse relation with the fundamental current.

Keywords: harmonic distortion analysis, power quality, PV systems, residential distribution system

Procedia PDF Downloads 250