Search results for: guided construction
3243 CFD Simulation Research on a Double Diffuser for Wind Turbines
Authors: Krzysztof Skiba, Zdzislaw Kaminski
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Wind power is based on a variety of construction solutions to convert wind energy into electrical energy. These constructions are constrained by the correlation between their energy conversion efficiency and the area they occupy. Their energy conversion efficiency can be improved by wind tunnel tests of a rotor as a diffuser to optimize shapes of aerodynamic elements, to adapt these elements to changing conditions and to increase airflow intensity. This paper discusses the results of computer simulations and aerodynamic analyzes of this innovative diffuser design. The research aims at determining the aerodynamic phenomena triggered by the airflow inside this construction, and developing a design to improve the efficiency of the wind turbine. The research results enable us to design a diffuser with a double Venturi nozzle and specially shaped blades. The design of this type uses Bernoulli’s law on the behavior of the flowing medium in the tunnel of a decreasing diameter. The air flowing along the tunnel changes its velocity so the rotor inside such a decreased tunnel diameter rotates faster in this airflow than does the wind outside this tunnel, which makes the turbine more efficient. Additionally, airflow velocity is improved by applying aerodynamic rings with extended trailing edges to achieve controlled turbulent vortices.Keywords: wind turbine, renewable energy, cfd, numerical analysis
Procedia PDF Downloads 3103242 Resilience in Patients with Chronic Kidney Disease in Hemodialysis
Authors: Gomes C. C. Izabel, Lanzotti B. Rafaela, Orlandi S. Fabiana
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Chronic Kidney Disease is considered a serious public health problem. The exploitation of resilience has been guided by studies conducted in various contexts, especially in hemodialysis, since the impact of diagnosis and restrictions produced during the treatment process because, despite advances in treatment, remains the stigma of the disease and the feeling of pain, hopelessness, low self-esteem and disability. The objective was to evaluate the level of resilience of patients in chronic renal dialysis. This is a descriptive, correlational, cross and quantitative research. The sample consisted of 100 patients from a Renal Replacement Therapy Unit in the countryside of São Paulo. For data collection were used the characterization instrument of Participants and the Resilience Scale. There was a predominance of males (70.0%) were Caucasian (45.0%) and had completed elementary education (34.0%). The average score obtained through the Resilience Scale was 131.3 (± 20.06) points. The resiliency level submitted may be considered satisfactory. It is expected that this study will assist in the preparation of programs and actions in order to avoid possible situations of crises faced by chronic renal patients.Keywords: hemodialysis units, renal dialysis, renal insufficiency chronic, resilience psychological
Procedia PDF Downloads 2823241 Design and Construction of an Intelligent Multiplication Table for Enhanced Education and Increased Student Engagement
Authors: Zahra Alikhani Koopaei
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In the fifth lesson of the third-grade mathematics book, students are introduced to the concept of multiplication. However, some students showed a lack of interest in learning this topic. To address this, a simple electronic multiplication table was designed with the aim of making the concept of multiplication entertaining and engaging for students. It provides them with moments of excitement during the learning process. To achieve this goal, a device was created that produced a bell sound when two wire ends were connected. Each wire end was connected to a specific number in the multiplication table, and the other end was linked to the corresponding answer. Consequently, if the answer is correct, the bell will ring. This study employs interactive and engaging methods to teach mathematics, particularly to students who have previously shown little interest in the subject. By integrating game-based learning and critical thinking, we observed an increase in understanding and interest in learning multiplication compared to before using this method. This further motivated the students. As a result, the intelligent multiplication table was successfully designed. Students, under the instructor's supervision, could easily construct the device during the lesson. Through the implementation of these operations, the concept of multiplication was firmly established in the students' minds. Engaging multiple intelligences in each student enhances a more stable and improved understanding of the concept of multiplication.Keywords: intelligent multiplication table, design, construction, education, increased interest, students
Procedia PDF Downloads 693240 Analyses of Copper Nanoparticles Impregnated Wood and Its Fungal Degradation Performance
Authors: María Graciela Aguayo, Laura Reyes, Claudia Oviedo, José Navarrete, Liset Gómez, Hugo Torres
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Most wood species used in construction deteriorate when exposed to environmental conditions that favor wood-degrading organisms’ growth. Therefore, chemical protection by impregnation allows more efficient use of forest resources extending the wood useful life. A wood protection treatment which has attracted considerable interest in the scientific community during the last decade is wood impregnation with nano compounds. Radiata pine is the main wood species used in the Chilean construction industry, with total availability of 8 million m³ sawn timber. According to the requirements of the American Wood Protection Association (AWPA) and the Chilean Standards (NCh) radiata pine timber used in construction must be protected due to its low natural durability. In this work, the impregnation with copper nanoparticles (CuNP) was studied in terms of penetration and its protective effect against wood rot fungi. Two concentrations: 1 and 3 g/L of NPCu were applied by impregnation on radiata pine sapwood. Test penetration under AWPA A3-91 standard was carried out, and wood decay tests were performed according to EN 113, with slight modifications. The results of penetration for 1 g/L CuNP showed an irregular total penetration, and the samples impregnated with 3 g/L showed a total penetration with uniform concentration (blue color in all cross sections). The impregnation wood mass losses due to fungal exposure were significantly reduced, regardless of the concentration of the solution or the fungus. In impregnated wood samples, exposure to G. trabeum resulted ML values of 2.70% and 1.19% for 1 g/L and 3 g/L CuNP, respectively, and exposure to P. placenta resulted in 4.02% and 0.70%-ML values for 1 g/L and 3 g/L CuNP, respectively. In this study, the penetration analysis confirmed a uniform distribution inside the wood, and both concentrations were effective against the tested fungi, giving mass loss values lower than 5%. Therefore, future research in wood preservatives should focus on new nanomaterials that are more efficient and environmentally friendly. Acknowledgments: CONICYT FONDEF IDeA I+D 2019, grant number ID19I10122.Keywords: copper nanoparticles, fungal degradation, radiata pine wood, wood preservation
Procedia PDF Downloads 1993239 Gypsum Composites with CDW as Raw Material
Authors: R. Santos Jiménez, A. San-Antonio-González, M. del Río Merino, M. González Cortina, C. Viñas Arrebola
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On average, Europe generates around 890 million tons of construction and demolition waste (CDW) per year and only 50% of these CDW are recycled. This is far from the objectives determined in the European Directive for 2020 and aware of this situation, the European Countries are implementing national policies to prevent the waste that can be avoidable and to promote measures to increase recycling and recovering. In Spain, one of these measures has been the development of a CDW recycling guide for the manufacture of mortar, concrete, bricks and lightweight aggregates. However, there is still not enough information on the possibility of incorporating CDW materials in the manufacture of gypsum products. In view of the foregoing, the Universidad Politécnica de Madrid is creating a database with information on the possibility of incorporating CDW materials in the manufacture of gypsum products. The objective of this study is to improve this database by analysing the feasibility of incorporating two different CDW in a gypsum matrix: ceramic waste bricks (perforated brick and double hollow brick), and extruded polystyrene (XPS) waste. Results show that it is possible to incorporate up to 25% of ceramic waste and 4% of XPS waste over the weight of gypsum in a gypsum matrix. Furhtermore, with the addition of ceramic waste an 8% of surface hardness increase and a 25% of capillary water absorption reduction can be obtained. On the other hand, with the addition of XPS, a 26% reduction of density and a 37% improvement of thermal conductivity can be obtained.Keywords: CDW, waste materials, ceramic waste, XPS, construction materials, gypsum
Procedia PDF Downloads 5103238 Challenging the Theory of Mind: Autism Spectrum Disorder, Social Construction, and Biochemical Explanation
Authors: Caroline Kim
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The designation autism spectrum disorder (ASD) groups complex disorders in the development of the brain. Autism is defined essentially as a condition in which an individual lacks a theory of mind. The theory of mind, in this sense, explains the ability of an individual to attribute feelings, emotions, or thoughts to another person. An autistic patient is characteristically unable to determine what an interlocutor is feeling, or to understand the beliefs of others. However, it is possible that autism cannot plausibly characterized as the lack of theory of mind in an individual. Genes, the bran, and its interplay with environmental factors may also cause autism. A mutation in a gene may be hereditary, or instigated by diseases such as mumps. Though an autistic patient may experience abnormalities in the cerebellum and the cortical regions, these are in fact only possible theories as to a biochemical explanation behind the disability. The prevailing theory identifying autism with lacking the theory of mind is supported by behavioral observation, but this form of observation is itself determined by socially constructed standards, limiting the possibility for empirical verification. The theory of mind infers that the beliefs and emotions of people are causally based on their behavior. This paper demonstrates the fallacy of this inference, critiquing its basis in socially constructed values, and arguing instead for a biochemical approach free from the conceptual apparatus of language and social expectation.Keywords: autism spectrum disorder, sociology of psychology, social construction, the theory of mind
Procedia PDF Downloads 4033237 Students’ Assessment of Teachers’ Attitude in Universities in Ondo State, Nigeria
Authors: Omoniyi A. Olubunmi, Omoniyi Olayide M.
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This study was designed to assess the attitudes of Nigerian university teachers by their students in terms of teachers’ attitude to work, teaching and students. The study was a survey, and made use of the researcher’s designed questionnaire tagged Students’ Assessment Teachers Inventory (SATI), comprising 20 items, was used to collect data. The respondents were 300 students which were randomly selected from three universities in Ondo State. The SATI elicited information on different aspects of teachers’ attitude to work, teaching and students. The study was guided by two hypotheses. Data collected were analyzed using Pearson-r. The result showed that there was a significant relationship between teachers’ attitude to work (r = 0.343, p<0.01), teaching (r = 0.594, p<0.01) and students (r = 0.487, p<0.01). The study concluded that teachers’ attitudes to teaching profession in higher institutions in Ondo State were not favorable and this could be improved through capacity building for effective pedagogical skills, conducive environment, well equipped libraries and laboratories, and provision of incentives for university teachers.Keywords: capacity building, pedagogical skills, teachers’ attitude, students’ assessment
Procedia PDF Downloads 2923236 Influence of Procurement Methods on Cost Performance of Building Projects in Gombe State, Nigeria
Authors: S. U. Kunya, S. Abdulkadir, M. A. Anas, L. Z. Adam
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Procurement methods is described as systems of contractual arrangements used by the contractor in order to secure the design and construction services based on the stipulated cost and within the required time and quality. Despite that, major projects in the Nigerian construction industry failed because of wrong procurement methods with major consequences leads to cost overrun which needs to find lasting solution. The aim of the study is to evaluate the influence of procurement methods on cost performance of building projects in Gombe State, Nigeria. Study adopts descriptive and explorative design approach. Data were collected through administering of one hundred questionnaire using convenient sampling techniques. Data analyses using percentages, mean value and Anova analysis. Major finding show that more than fifty percent (50%) of procurement methods available are mainly utilized in the study area and the top procurement methods that have high impacts on cost performance as compare with the other methods is project management and direct labour procurement methods. The results of hypothesis’ tests with pvalue 0.12 and 0.07 validated that there was no significant variation in the perception of stakeholders’ on the impacts of procurements methods on cost performance. Therefore, the study concluded that projects management and direct labour are the most appropriate procurement methods that will ensure successful completion of project at stipulated cost in building projects.Keywords: cost, effects, performance, procurement, projects
Procedia PDF Downloads 2243235 Study of Ultrasonic Waves in Unidirectional Fiber-Reinforced Composite Plates for the Aerospace Applications
Authors: DucTho Le, Duy Kien Dao, Quoc Tinh Bui, Haidang Phan
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The article is concerned with the motion of ultrasonic guided waves in a unidirectional fiber-reinforced composite plate under acoustic sources. Such unidirectional composite material has orthotropic elastic properties as it is very stiff along the fibers and rather compliant across the fibers. The dispersion equations of free Lamb waves propagating in an orthotropic layer are derived that results in the dispersion curves. The connection of these equations to the Rayleigh-Lamb frequency relations of isotropic plates is discussed. By the use of reciprocity in elastodynamics, closed-form solutions of elastic wave motions subjected to time-harmonic loads in the layer are computed in a simple manner. We also consider the problem of Lamb waves generated by a set of time-harmonic sources. The obtained computations can be very useful for developing ultrasound-based methods for nondestructive evaluation of composite structures.Keywords: lamb waves, fiber-reinforced composite plates, dispersion equations, nondestructive evaluation, reciprocity theorems
Procedia PDF Downloads 1493234 Lines for a Different Approach in Music Education: A Review of the Concept of Musicality
Authors: Emmanuel Carlos De Mata Castrejón
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Music education has shown to be connected to many areas of sciences and arts, it has also been associated with several facets of human life. The many aspects around the study of music and education, make very difficult for the music educator to find a way through, even though there are lots of methods of teaching music to young children, they are different between one another and so are the students. For the music to help improve children’s development, it is necessary for the children to explore their musicality as they explore their creativity; it must be a challenging, playful, and enjoyable activity. The purpose of this investigation is to focus the music education not in the music, nor the teaching, but the children to be guided through their own musicality. The first approach to this kind of music education comes from the Active learning methods during the nineteenth century, most of which are still used around the world, sometimes with modifications to fit a certain place or type of students. This approach on children’s musicality requires some knowledge of music, pedagogy, and developmental psychology at least, but more important than the theory or the method used for music education, the focus should be on developing the student’s musicality, considering the complexity of this concept. To get this, it is needed, indeed, far more research in the topic, so this is a call for collaborative research and for interdisciplinary teams to emerge. This is a review of authors and methods in music education trying to trace a line pointing to transdisciplinary work and pursuing the development of children’s musicality.Keywords: children, methods, music education, musicality
Procedia PDF Downloads 3323233 Comparative Analysis of Three Types of Recycled Aggregates and its Use in Masonry Mortar Fabrication
Authors: Mariano Gonzalez Cortina, Pablo Saiz Martinez, Francisco Fernandez Martinez, Antonio Rodriguez Sanchez
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Construction sector incessant activity of the last years preceding the crisis has originated a high waste generation and an increased use of raw materials. The main aim of this research is to compare three types of recycled aggregates and the feasibility to incorporate them into masonry mortar fabrication. The tests were developed using two types of binders: CEM II/B-L 32.5 N and CEM IV/B (V) 32.5 N. 50%, 75% and 100% of natural sand were replaced with three types of recycled aggregates. Cement-to-aggregate by dry weight proportions were 1:3 and 1:4. Physical and chemical characterization of recycled aggregates showed continues particle size distribution curve, lower density and higher absorption, which was the reason to use additive to obtain required mortar consistency. Main crystalline phases determined in the X-Ray diffraction test were calcite, quartz, and gypsum. Performed tests show that cement-based mortars fabricated with CEM IV/B (V) 32. 5 N can incorporate recycled aggregates coming from ceramic, concrete and mixed recycling processes, using 1:3 and 1:4 cement-to-aggregate proportions, complying with the limits established by the Spanish standards. It was concluded that recycled mortar coming from concrete recycling process is the one which presents better characteristics.Keywords: construction and demolition waste, masonry mortar, mechanical properties, recycled aggregate, waste treatment
Procedia PDF Downloads 4233232 Thermal Behavior of a Ventilated Façade Using Perforated Ceramic Bricks
Authors: Helena López-Moreno, Antoni Rodríguez-Sánchez, Carmen Viñas-Arrebola, Cesar Porras-Amores
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The ventilated façade has great advantages when compared to traditional façades as it reduces the air conditioning thermal loads due to the stack effect induced by solar radiation in the air chamber. Optimizing energy consumption by using a ventilated façade can be used not only in newly built buildings but also it can be implemented in existing buildings, opening the field of implementation to energy building retrofitting works. In this sense, the following three prototypes of façade where designed, built and further analyzed in this research: non-ventilated façade (NVF); slightly ventilated façade (SLVF) and strongly ventilated façade (STVF). The construction characteristics of the three facades are based on the Spanish regulation of building construction “Technical Building Code”. The façades have been monitored by type-k thermocouples in a representative day of the summer season in Madrid (Spain). Moreover, an analysis of variance (ANOVA) with repeated measures, studying the thermal lag in the ventilated and no-ventilated façades has been designed. Results show that STVF façade presents higher levels of thermal inertia as the thermal lag reduces up to 100% (daily mean) compared to the non-ventilated façade. In addition, the statistical analysis proves that an increase of the ventilation holes size in STVF façades does not improve the thermal lag significantly (p > 0.05) when compared to the SLVF façade.Keywords: ventilated façade, energy efficiency, thermal behavior, statistical analysis
Procedia PDF Downloads 4913231 Using the Delphi Method to Determine the Change in Knowledge and Skills of Professional Quantity Surveyors as a Result of COVID-19 Pandemic
Authors: Veronica Kah Jo Wong, Yoke Mui Lim, Nurul Sakina Mokhtar Azizi
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The impact on the construction industry in Malaysia is unprecedented, as the government implemented a lockdown to restrict human movement in an effort to stop COVID-19 from spreading. Quantity surveyor (QS), as one of the key construction professionals, found that the working practices and environments for quantity surveyors today have changed due to the current pandemic. The QS profession must deal not only with changes in project issues but also with a different working environment in which most people are required to work from home and follow the standard operating procedures. Therefore, QS should be flexible, agile, and have the capability to adapt to the current working practices by strengthening their competencies. Adapting to the current and recovering environment of COVID-19 may result in the emergence of a new competence such as skill and knowledge for QS in order to maintain the quality of performance in the delivery of their professional services. Thus, this paper's objective is to investigate the changes in knowledge and skills in quantity surveyors. The data will be collected through interviews with registered professional QS to gain better insights that are specific in this industry, and the findings will be verified using the Delphi method. It is hoped that new knowledge and skill will be found from the study and will not only contribute to the betterment of the professional QS but also in guiding higher learning institutions to incorporate the new competencies into their curriculum.Keywords: competency, COVID-19 pandemic, Malaysia, quantity surveying
Procedia PDF Downloads 1293230 Numerical Analysis of Rainfall-Induced Roadside Slope Failures and Their Stabilizing Solution
Authors: Muhammad Suradi, Sugiarto, Abdullah Latip
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Many roadside slope failures occur during the rainy season, particularly in the period of extreme rainfall along Connecting National Road of Salubatu-Mambi, West Sulawesi, Indonesia. These occurrences cause traffic obstacles and endanger people along and around the road. Research collaboration between P2JN (National Road Construction Board) West Sulawesi Province, who authorize to supervise the road condition, and Ujung Pandang State Polytechnic (Applied University) was established to cope with the landslide problem. This research aims to determine factors triggering roadside slope failures and their optimum stabilizing solution. To achieve this objective, site observation and soil investigation were carried out to obtain parameters for analyses of rainfall-induced slope instability and reinforcement design using the SV Flux and SV Slope software. The result of this analysis will be taken into account for the next analysis to get an optimum design of the slope reinforcement. The result indicates some factors such as steep slopes, sandy soils, and unvegetated slope surface mainly contribute to the slope failures during intense rainfall. With respect to the contributing factors as well as construction material and technology, cantilever/butressing retaining wall becomes the optimum solution for the roadside slope reinforcement.Keywords: roadside slope, failure, rainfall, slope reinforcement, optimum solution
Procedia PDF Downloads 1063229 Taking Sides: The Frames of Online Media on the Bilateral Relationship between Moslem Countries (Malaysia and Indonesia)
Authors: Gatut Priyowidodo, I. I. Indrayani
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The relations between Indonesia and Malaysia are always full of colors. Indonesia is always known as old brother of Malaysia since it has similar history, religion also socio culturally. Some decades show that the declination of relationship the both countries. Another time, as ASEAN members the two countries devotes their nationalities to purify their collective identities as Eastern. The objective of the research is to extricate the construction of Kompas online and Utusan online toward news coverage of the borders dispute between Indonesia-Malaysia in 2010. This research is proposed to examine central issues which reported by Kompas online and Utusan online consistently. As a media industry, Kompas coverage dominates circulation nationally. Kompas.com was the pioneer of online news in Indonesia and born in reformation era. Utusan is prominent media industry in Malaysia that conducted by UMNO as the ruling party in Malaysia for some periods. The method used in this research is framing method by Robert N. Entman’s which consists of four steps identification: defining problem, diagnosing causes, moral judgment and a treatment recommendation. This research found that Kompas news covered the border dispute must be negotiated as recognition of Indonesia dignity. In contrary, Utusan’s spectacle focused on the Indonesia demonstrans anarchism during the dispute.Keywords: online media, media construction, the border dispute, Indonesia-Malaysia’s bilateral relations
Procedia PDF Downloads 3413228 Design, Analysis and Construction of a 250vac 8amps Arc Welding Machine
Authors: Anthony Okechukwu Ifediniru, Austin Ikechukwu Gbasouzor, Isidore Uche Uju
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This article is centered on the design, analysis, construction, and test of a locally made arc welding machine that operates on 250vac with 8 amp output taps ranging from 60vac to 250vac at a fixed frequency, which is of benefit to urban areas; while considering its cost-effectiveness, strength, portability, and mobility. The welding machine uses a power supply to create an electric arc between an electrode and the metal at the welding point. A current selector coil needed for current selection is connected to the primary winding. Electric power is supplied to the primary winding of its transformer and is transferred to the secondary winding by induction. The voltage and current output of the secondary winding are connected to the output terminal, which is used to carry out welding work. The output current of the machine ranges from 110amps for low current welding to 250amps for high current welding. The machine uses a step-down transformer configuration for stepping down the voltage in order to obtain a high current level for effective welding. The welder can adjust the output current within a certain range. This allows the welder to properly set the output current for the type of welding that is being performed. The constructed arc welding machine was tested by connecting the work piece to it. Since there was no shock or spark from the transformer’s laminated core and was successfully used to join metals, it confirmed and validated the design.Keywords: AC current, arc welding machine, DC current, transformer, welds
Procedia PDF Downloads 1813227 Passivization: as Syntactic Argument Decreasing Parameter in Boro
Authors: Ganga Brahma
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Boro employs verbs hooked up with morphemes which lead verbs to adjust with their arguments and hence, affecting the whole of sentence structures. This paper is based on few such syntactic parameters which are usually considered as argument decreasing parameters in linguistic works. Passivizing of few transitive clauses which are usually construed from the verbs occurring with certain morphemes and representation in middle constructions are few of such strategies which lead to conceptualizing of decreasing of syntactic arguments from a sentence. This paper focuses on the mentioned linguistic strategies and attempts to describe the linguistic processes as for how these parameters work in languages especially by concentrating on a particular Tibeto-Burman language i.e. Boro. Boro is a Tibeto-Burman language widely spoken in parts of the north-eastern regions of India. It has an agglutinative nature in forming words as well as clauses. There is a morpheme ‘za’ which means ‘to happen, become’ in Boro whose appearances with verb roots denotes an idea of the subject being passivized. Passivization, usually has notions that it is a reversed representation of its active sentence forms in the terms of argument placements. (However, it is not accountably true as passives and actives have some distinct features of their own and independent of one and the other.) This particular work will concentrate on the semantics of passivization at the same time along with its syntactic reality. The verb khɑo meaning ‘to steal’ offers a sense of passivization with the appearance of the morpheme zɑ which means ‘to happen, become’ (e.g Zunu-ɑ lama-ɑo phɯisɑ khɑo-zɑ-bɑi; Junu-NOM road-LOC money steal-PASS-PRES: Junu got her money stolen on the road). The focus, here, is more on the argument placed at the subject position (i.e. Zunu) and the event taken place. The semantics of such construction asks for the agent because without an agent the event could not have taken place. However, the syntactic elements fill the slots of relegated or temporarily deleted agent which, infact, is the actual subject cum agent in its active representation. Due to the event marker ‘zɑ’ in this presentation it affords to reduce one participant from such a situation which in actual is made up of three participants. Hence, the structure of di-transitive construction here reduces to mono-transitive structure. Unlike passivization, middle construction does not allow relegation of the agents. It permanently deletes agents. However, it also focuses on the fore-grounded subject and highlighting on the changed states on the subjects which happens to be the underlying objects of their respective transitive structures (with agents). This work intends to describe how these two parameters which are different at their semantic realization can meet together at a syntactic level in order to create a linguistic parameter that decreases participants from their actual structures which are with more than one participant.Keywords: argument-decrease, middle-construction, passivization, transitivity-intransitivity
Procedia PDF Downloads 2373226 Alkali Silica Reaction Mitigation and Prevention Measures for Arkansas Local Aggregates
Authors: Amin Kamal Akhnoukh, Lois Zaki Kamel, Magued Mourad Barsoum
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The objective of this research is to mitigate and prevent the alkali silica reactivity (ASR) in highway construction projects. ASR is a deleterious reaction initiated when the silica content of the aggregate reacts with alkali hydroxides in cement in the presence of relatively high moisture content. The ASR results in the formation of an expansive white colored gel-like material which forms the destructive tensile stresses inside hardened concrete. In this research, different types of local aggregates available in the State of Arkansas were mixed and mortar bars were poured according to the ASTM specifications. Mortar bars expansion was measured versus time and aggregates with potential ASR problems were detected. Different types of supplementary cementitious materials (SCMs) were used in remixing mortar bars with highly reactive aggregates. Length changes for remixed bars proved that different types of SCMs can be successfully used in reducing the expansive effect of ASR. SCMs percentage by weight is highly dependent on the SCM type. The result of this study will help avoiding future losses due to ASR cracking in construction project and reduce the maintenance, repair, and replacement budgets required for highways network.Keywords: alkali silica reaction, aggregates, misture, cracks, Mortar Bar Test, supplementary cementitious materials
Procedia PDF Downloads 3343225 Relative Clause Attachment Ambiguity Resolution in L2: the Role of Semantics
Authors: Hamideh Marefat, Eskandar Samadi
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This study examined the effect of semantics on processing ambiguous sentences containing Relative Clauses (RCs) preceded by a complex Determiner Phrase (DP) by Persian-speaking learners of L2 English with different proficiency and Working Memory Capacities (WMCs). The semantic relationship studied was one between the subject of the main clause and one of the DPs in the complex DP to see if, as predicted by Spreading Activation Model, priming one of the DPs through this semantic manipulation affects the L2ers’ preference. The results of a task using Rapid Serial Visual Processing (time-controlled paradigm) showed that manipulation of the relationship between the subject of the main clause and one of the DPs in the complex DP preceding RC has no effect on the choice of the antecedent; rather, the L2ers' processing is guided by the phrase structure information. Moreover, while proficiency did not have any effect on the participants’ preferences, WMC brought about a difference in their preferences, with a DP1 preference by those with a low WMC. This finding supports the chunking hypothesis and the predicate proximity principle, which is the strategy also used by monolingual Persian speakers.Keywords: semantics, relative clause processing, ambiguity resolution, proficiency, working memory capacity
Procedia PDF Downloads 6233224 Mitigation of Offshore Piling Noise Effects on Marine Mammals
Authors: Waled A. Dawoud, Abdelazim M. Negm, Nasser M. Saleh
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Offshore piling generates underwater sound at level high enough to cause physical damage or hearing impairment to the marine mammals. Several methods can be used to mitigate the effect of underwater noise from offshore pile driving on marine mammals which can be divided into three main approaches. The first approach is to keep the mammal out of the high-risk area by using aversive sound waves produced by acoustic mitigation devices such as playing-back of mammal's natural predator vocalization, alarm or distress sounds, and anthropogenic sound. The second approach is to reduce the amount of underwater noise from pile driving using noise mitigation techniques such as bubble curtains, isolation casing, and hydro-sound dampers. The third approach is to eliminate the overlap of underwater waves by using prolonged construction process. To investigate the effectiveness of different noise mitigation methods; a pile driven with 235 kJ rated energy diesel hammer near Jeddah Coast, Kingdom of Saudi Arabia was used. Using empirical sound exposure model based on Red Sea characteristics and limits of National Oceanic and Atmospheric Administration; it was found that the aversive sound waves should extend to 1.8 km around the pile location. Bubble curtains can reduce the behavioral disturbance area up to 28%; temporary threshold shift up to 36%; permanent threshold shift up to 50%; and physical injury up to 70%. Isolation casing can reduce the behavioral disturbance range up to 12%; temporary threshold shift up to 21%; permanent threshold shift up to 29%; and physical injury up to 46%. Hydro-sound dampers efficiency depends mainly on the used technology and it can reduce the behavioral disturbance range from 10% to 33%; temporary threshold shift from 18% to 25%; permanent threshold shift from 32% to 50%; and physical injury from 46% to 60%. To prolong the construction process, it was found that the single pile construction, use of soft start, and keep time between two successive hammer strikes more than 3 seconds are the most effective techniques.Keywords: offshore pile driving, sound propagation models, noise effects on marine mammals, Underwater noise mitigation
Procedia PDF Downloads 5453223 Green Materials for Hot Mixed Asphalt Production
Authors: Salisu Dahiru, Jibrin M. Kaura, Abubakar I. Jumare, Sulaiman M. Mahmood
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Reclaimed asphalt, used automobile tires and rice husk, were regarded as waste. These materials could be used in construction of new roads and for roads rehabilitation. Investigation into the production of a Green Hot Mixed Asphalt (GHMA) pavement using Reclaimed Asphalt Pavement (RAP) as partial replacement for coarse aggregate, Crumb Rubber (CR) from waste automobile tires as modifier for bitumen binder and Rice Husk Ash (RHA) as partial replacement of ordinary portland cement (OPC) filler, for roads construction and rehabilitation was presented. 30% Reclaimed asphalt of total aggregate, 15% Crumb Rubber of total binder content, 5% Rice Husk Ash of total mix, and 5.2% Crumb Rubber Modified Bitumen content were recommended for optimum performance. Loss of marshal stability was investigated on mix with the recommended optimum CRMB. The mix revealed good performance with only about 13% loss of stability after 24 hours of immersion in hot water bath, as against about 24% marshal stability lost reported in previous studies for conventional Hot Mixed Asphalt (HMA).Keywords: rice husk, reclaimed asphalt, filler, crumb rubber, bitumen content green hot mix asphalt
Procedia PDF Downloads 3353222 Regained Oral Tradition and Identity Construction in House Made of Dawn
Authors: Yi Hu
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House Made of Dawn is famous novelist N. Scott Momaday’s Pulitzer-winning novel in 1968. The novel tells a story of the struggling life of an Indian named Abel, following the pattern of leaving home, coming home, leaving again, and returning home at the closure of the story. It touches upon the theme of the relationship between Indianness, identity, and tradition. Abel’s confusion over his identity and his constant struggle and exploration of his identity are pivoted on the tradition of oral literature in the form of story-telling. Therefore, this paper aims to analyze the important role of oral tradition in constructing Abel’s Indian cultural identity. The significance of the research lies in two aspects: first of all, the research aims to provide an enlightening perspective for Momaday’s House Made of Dawn in order to gain a better understanding of the novel. Secondly, by emphasizing the importance of traditional culture in identity construction, the research hopes to provide some referential value for people who suffer from identity predicament in modern society. Finally, the paper draws a conclusion that alienation from traditional tribal culture will result in a serious physical and psychological crisis for Indian people. Indian people should adhere to their traditional culture in order to construct their unique cultural identity.Keywords: House Made of Dawn, identity, N.Scott.Momaday, oral tradition
Procedia PDF Downloads 2253221 Design Development of Floating Performance Structure for Coastal Areas in the Maltese Islands
Authors: Rebecca E. Dalli Gonzi, Joseph Falzon
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Background: Islands in the Mediterranean region offer opportunities for various industries to take advantage of the facilitation and use of versatile floating structures in coastal areas. In the context of dense land use, marine structures can contribute to ensure both terrestrial and marine resource sustainability. Objective: The aim of this paper is to present and critically discuss an array of issues that characterize the design process of a floating structure for coastal areas and to present the challenges and opportunities of providing such multifunctional and versatile structures around the Maltese coastline. Research Design: A three-tier research design commenced with a systematic literature review. Semi-structured interviews with stakeholders including a naval architect, a marine engineer and civil designers were conducted. A second stage preceded a focus group with stakeholders in design and construction of marine lightweight structures. The three tier research design ensured triangulation of issues. All phases of the study were governed by research ethics. Findings: Findings were grouped into three main themes: excellence, impact and implementation. These included design considerations, applications and potential impacts on local industry. Literature for the design and construction of marine structures in the Maltese Islands presented multiple gaps in the application of marine structures for local industries. Weather conditions, depth of sea bed and wave actions presented limitations on the design capabilities of the structure. Conclusion: Water structures offer great potential and conclusions demonstrate the applicability of such designs for Maltese waters. There is still no such provision within Maltese coastal areas for multi-purpose use. The introduction of such facilities presents a range of benefits for visiting tourists and locals thereby offering wide range of services to tourism and marine industry. Costs for construction and adverse weather conditions were amongst the main limitations that shaped design capacities of the water structures.Keywords: coastal areas, lightweight, marine structure, multi purpose, versatile, floating device
Procedia PDF Downloads 1613220 Design, Construction and Evaluation of a Mechanical Vapor Compression Distillation System for Wastewater Treatment in a Poultry Company
Authors: Juan S. Vera, Miguel A. Gomez, Omar Gelvez
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Water is Earth's most valuable resource, and the lack of it is currently a critical problem in today’s society. Non-treated wastewaters contribute to this situation, especially those coming from industrial activities, as they reduce the quality of the water bodies, annihilating all kind of life and bringing disease to people in contact with them. An effective solution for this problem is distillation, which removes most contaminants. However, this approach must also be energetically efficient in order to appeal to the industry. In this endeavour, most water distillation treatments fail, with the exception of the Mechanical Vapor Compression (MVC) distillation system, which has a great efficiency due to energy input by a compressor and the latent heat exchange. This paper presents the process of design, construction, and evaluation of a Mechanical Vapor Compression (MVC) distillation system for the main Colombian poultry company Avidesa Macpollo SA. The system will be located in the principal slaughterhouse in the state of Santander, and it will work along with the Gas Energy Mixing system (GEM) to treat the wastewaters from the plant. The main goal of the MVC distiller, rarely used in this type of application, is to reduce the chlorides, Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD) levels according to the state regulations since the GEM cannot decrease them enough. The MVC distillation system works with three components, the evaporator/condenser heat exchanger where the distillation takes place, a low-pressure compressor which gives the energy to create the temperature differential between the evaporator and condenser cavities and a preheater to save the remaining energy in the distillate. The model equations used to describe how the compressor power consumption, heat exchange area and distilled water are related is based on a thermodynamic balance and heat transfer analysis, with correlations taken from the literature. Finally, the design calculations and the measurements of the installation are compared, showing accordance with the predictions in distillate production and power consumption, changing the temperature difference of the evaporator/condenser.Keywords: mechanical vapor compression, distillation, wastewater, design, construction, evaluation
Procedia PDF Downloads 1593219 Data and Model-based Metamodels for Prediction of Performance of Extended Hollo-Bolt Connections
Authors: M. Cabrera, W. Tizani, J. Ninic, F. Wang
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Open section beam to concrete-filled tubular column structures has been increasingly utilized in construction over the past few decades due to their enhanced structural performance, as well as economic and architectural advantages. However, the use of this configuration in construction is limited due to the difficulties in connecting the structural members as there is no access to the inner part of the tube to install standard bolts. Blind-bolted systems are a relatively new approach to overcome this limitation as they only require access to one side of the tubular section to tighten the bolt. The performance of these connections in concrete-filled steel tubular sections remains uncharacterized due to the complex interactions between concrete, bolt, and steel section. Over the last years, research in structural performance has moved to a more sophisticated and efficient approach consisting of machine learning algorithms to generate metamodels. This method reduces the need for developing complex, and computationally expensive finite element models, optimizing the search for desirable design variables. Metamodels generated by a data fusion approach use numerical and experimental results by combining multiple models to capture the dependency between the simulation design variables and connection performance, learning the relations between different design parameters and predicting a given output. Fully characterizing this connection will transform high-rise and multistorey construction by means of the introduction of design guidance for moment-resisting blind-bolted connections, which is currently unavailable. This paper presents a review of the steps taken to develop metamodels generated by means of artificial neural network algorithms which predict the connection stress and stiffness based on the design parameters when using Extended Hollo-Bolt blind bolts. It also provides consideration of the failure modes and mechanisms that contribute to the deformability as well as the feasibility of achieving blind-bolted rigid connections when using the blind fastener.Keywords: blind-bolted connections, concrete-filled tubular structures, finite element analysis, metamodeling
Procedia PDF Downloads 1583218 Evaluating the Implementation of Machine Learning Techniques in the South African Built Environment
Authors: Peter Adekunle, Clinton Aigbavboa, Matthew Ikuabe, Opeoluwa Akinradewo
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The future of machine learning (ML) in building may seem like a distant idea that will take decades to materialize, but it is actually far closer than previously believed. In reality, the built environment has been progressively increasing interest in machine learning. Although it could appear to be a very technical, impersonal approach, it can really make things more personable. Instead of eliminating humans out of the equation, machine learning allows people do their real work more efficiently. It is therefore vital to evaluate the factors influencing the implementation and challenges of implementing machine learning techniques in the South African built environment. The study's design was one of a survey. In South Africa, construction workers and professionals were given a total of one hundred fifty (150) questionnaires, of which one hundred and twenty-four (124) were returned and deemed eligible for study. Utilizing percentage, mean item scores, standard deviation, and Kruskal-Wallis, the collected data was analyzed. The results demonstrate that the top factors influencing the adoption of machine learning are knowledge level and a lack of understanding of its potential benefits. While lack of collaboration among stakeholders and lack of tools and services are the key hurdles to the deployment of machine learning within the South African built environment. The study came to the conclusion that ML adoption should be promoted in order to increase safety, productivity, and service quality within the built environment.Keywords: machine learning, implementation, built environment, construction stakeholders
Procedia PDF Downloads 1323217 Building Information Modeling-Based Information Exchange to Support Facilities Management Systems
Authors: Sandra T. Matarneh, Mark Danso-Amoako, Salam Al-Bizri, Mark Gaterell
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Today’s facilities are ever more sophisticated and the need for available and reliable information for operation and maintenance activities is vital. The key challenge for facilities managers is to have real-time accurate and complete information to perform their day-to-day activities and to provide their senior management with accurate information for decision-making process. Currently, there are various technology platforms, data repositories, or database systems such as Computer-Aided Facility Management (CAFM) that are used for these purposes in different facilities. In most current practices, the data is extracted from paper construction documents and is re-entered manually in one of these computerized information systems. Construction Operations Building information exchange (COBie), is a non-proprietary data format that contains the asset non-geometric data which was captured and collected during the design and construction phases for owners and facility managers use. Recently software vendors developed add-in applications to generate COBie spreadsheet automatically. However, most of these add-in applications are capable of generating a limited amount of COBie data, in which considerable time is still required to enter the remaining data manually to complete the COBie spreadsheet. Some of the data which cannot be generated by these COBie add-ins is essential for facilities manager’s day-to-day activities such as job sheet which includes preventive maintenance schedules. To facilitate a seamless data transfer between BIM models and facilities management systems, we developed a framework that enables automated data generation using the data extracted directly from BIM models to external web database, and then enabling different stakeholders to access to the external web database to enter the required asset data directly to generate a rich COBie spreadsheet that contains most of the required asset data for efficient facilities management operations. The proposed framework is a part of ongoing research and will be demonstrated and validated on a typical university building. Moreover, the proposed framework supplements the existing body of knowledge in facilities management domain by providing a novel framework that facilitates seamless data transfer between BIM models and facilities management systems.Keywords: building information modeling, BIM, facilities management systems, interoperability, information management
Procedia PDF Downloads 1153216 A Comparative Analysis of Thermal Performance of Building Envelope Types over Time
Authors: Aram Yeretzian, Yaser Abunnasr, Zahraa Makki, Betina Abi Habib
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Developments in architectural building typologies that are informed by prevalent construction techniques and socio-cultural practices generate different adaptations in the building envelope. While different building envelope types exhibit different climate responsive passive strategies, the individual and comparative thermal performance analysis resulting from these technologies is yet to be understood. This research aims to develop this analysis by selecting three building envelope types from three distinct building traditions by measuring the heat transmission in the city of Beirut. The three typical residential buildings are selected from the 1920s, 1940s, and 1990s within the same street to ensure similar climatic and urban conditions. Climatic data loggers are installed inside and outside of the three locations to measure indoor and outdoor temperatures, relative humidity, and heat flow. The analysis of the thermal measurements is complemented by site surveys on window opening, lighting, and occupancy in the three selected locations and research on building technology from the three periods. Apart from defining the U-value of the building envelopes, the collected data will help evaluate the indoor environments with respect to the thermal comfort zone. This research, thus, validates and contextualizes the role of building technologies in relation to climate responsive design.Keywords: architecture, wall construction, envelope performance, thermal comfort
Procedia PDF Downloads 2343215 Diversity in the Community - The Disability Perspective
Authors: Sarah Reker, Christiane H. Kellner
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From the perspective of people with disabilities, inequalities can also emerge from spatial segregation, the lack of social contacts or limited economic resources. In order to reduce or even eliminate these disadvantages and increase general well-being, community-based participation as well as decentralisation efforts within exclusively residential homes is essential. Therefore, the new research project “Index for participation development and quality of life for persons with disabilities”(TeLe-Index, 2014-2016), which is anchored at the Technische Universität München in Munich and at a large residential complex and service provider for persons with disabilities in the outskirts of Munich aims to assist the development of community-based living environments. People with disabilities should be able to participate in social life beyond the confines of the institution. Since a diverse society is a society in which different individual needs and wishes can emerge and be catered to, the ultimate goal of the project is to create an environment for all citizens–regardless of disability, age or ethnic background–that accommodates their daily activities and requirements. The UN-Convention on the Rights of Persons with Disabilities, which Germany also ratified, postulates the necessity of user-centered design, especially when it comes to evaluating the individual needs and wishes of all citizens. Therefore, a multidimensional approach is required. Based on this insight, the structure of the town-like center will be remodeled to open up the community to all people. This strategy should lead to more equal opportunities and open the way for a much more diverse community. Therefore, macro-level research questions were inspired by quality of life theory and were formulated as follows for different dimensions: •The user dimension: what needs and necessities can we identify? Are needs person-related? Are there any options to choose from? What type of quality of life can we identify? The economic dimension: what resources (both material and staff-related) are available in the region? (How) are they used? What costs (can) arise and what effects do they entail? •The environment dimension: what “environmental factors” such as access (mobility and absence of barriers) prove beneficial or impedimental? In this context, we have provided academic supervision and support for three projects (the construction of a new school, inclusive housing for children and teenagers with disabilities and the professionalization of employees with person-centered thinking). Since we cannot present all the issues of the umbrella-project within the conference framework, we will be focusing on one project more in-depth, namely “Outpatient Housing Options for Children and Teenagers with Disabilities”. The insights we have obtained until now will enable us to present the intermediary results of our evaluation. The most central questions pertaining to this part of the research were the following: •How have the existing network relations been designed? •What meaning (or significance) does the existing service offers and structures have for the everyday life of an external residential group? These issues underpinned the environmental analyses as well as the qualitative guided interviews and qualitative network analyses we carried out.Keywords: decentralisation, environmental analyses, outpatient housing options for children and teenagers with disabilities, qualitative network analyses
Procedia PDF Downloads 3653214 The Social Enterprise Model And Its Beneficiaries
Authors: Lorryn Williams
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This study will explore how the introduction of the for-profit social enterprise model affects the real lives of the individuals and communities that this model aims to help in South Africa. The congruence between organisational need construction and the real needs of beneficiaries, and whether the adoption of a profit driven model, such as social entrepreneurship, supports or discards these needs is key to answering the former question. By making use of qualitative methods, the study aims to collect empirical evidence that either supports the social entrepreneurship approach when compared to other programs such as vocational training programs or rejects it as less beneficial. It is the objective of this research to provide an answer to the question of whether the social enterprise model of conducting charity leaves the beneficiaries of non-profit organisations in a generally better or worse off position. The study will specifically explore the underlying assumptions the social entrepreneurship model makes, since the assumptions made concerning the uplifting effects it has on its beneficiaries may produce either real or assumed change for beneficiaries. The meaning of social cohesion and social capital for these organisations, the construction of beneficiary dependence and independence, the consideration of formal and informal economies beneficiaries engage in, and the extent to which sustainability is used as a brand, will be investigated. Through engaging the relevant literature, experts in the field of non-profit donorship and need implementation, organisations who have both adopted social enterprise programs and not, and most importantly, the beneficiaries themselves, it will be possible to provide answers to questions this study aims to answer.Keywords: social enterprise, beneficiaries, profit driven model, non-profit organizations
Procedia PDF Downloads 140