Search results for: building materials industry
10660 Investigation on Mechanical Properties of a Composite Material of Olive Flour Wood with a Polymer Matrix
Authors: Slim Souissi, Mohamed Ben Amar, Nesrine Bouhamed, Pierre Marechal
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The bio-composites development from biodegradable materials and natural fibers has a growing interest in the science of composite materials. The present work was conducted as part of a cooperation project between the Sfax University and the Havre University. This work consists in developing and monitoring the properties of a composite material of olive flour wood with a polymer matrix (urea formaldehyde). For this, ultrasonic non-destructive and destructive methods of characterization were used to optimize the mechanical and acoustic properties of the studied material based on the elaboration parameters.Keywords: bio-composite, olive flour wood, polymer matrix, ultrasonic methods, mechanical properties
Procedia PDF Downloads 49910659 Establishing a Change Management Model for Precision Machinery Industry in Taiwan
Authors: Feng-Tsung Cheng, Shu-Li Wang, Mei-Fang Wu, , Hui-Yu Chuang
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Due to the rapid development of modern technology, the widespread usage of the Internet makes business environment changing quickly. In order to be a leader in the global competitive market and to pursuit survive, “changing” becomes an unspoken rules need to follow for the company survival. The purpose of this paper is to build change model by using SWOT, strategy map, and balance scorecard, KPI and change management theory. The research findings indicate that organizational change plan formulated by the case company should require the employee to resist change factors and performance management system issues into consideration and must be set organizational change related programs, such as performance appraisal reward system, consulting and counseling mechanisms programs to improve motivation and reduce staff negative emotions. Then according to the model revised strategy maps and performance indicators proposed in this paper, such as strategy maps add and modify corporate culture, improve internal processes management, increase the growth rate of net income and other strategies. The performance indicators are based on strategy maps new and modified by adding net income growth rate, to achieve target production rate, manpower training achievement rates and other indicators, through amendments to achieve the company’s goal, be a leading brand of precision machinery industry.Keywords: organizational change, SWOT analysis, strategy maps, performance indicators
Procedia PDF Downloads 28610658 Development of Hybrid Materials Combining Biomass as Fique Fibers with Metal-Organic Frameworks, and Their Potential as Mercury Adsorbents
Authors: Karen G. Bastidas Gomez, Hugo R. Zea Ramirez, Manuel F. Ribeiro Pereira, Cesar A. Sierra Avila, Juan A. Clavijo Morales
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The contamination of water sources with heavy metals such as mercury has been an environmental problem; it has generated a high impact on the environment and human health. In countries such as Colombia, mercury contamination due to mining has reached levels much higher than the world average. This work proposes the use of fique fibers as adsorbent in mercury removal. The evaluation of the material was carried out under five different conditions (raw, pretreated by organosolv, functionalized by TEMPO oxidation, fiber functionalized plus MOF-199 and fiber functionalized plus MOF-199-SH). All the materials were characterized using FTIR, SEM, EDX, XRD, and TGA. Regarding the mercury removal, it was done under room pressure and temperature, also pH = 7 for all materials presentations, followed by Atomic Absorption Spectroscopy. The high cellulose content in fique is the main particularity of this lignocellulosic biomass since the degree of oxidation depends on the number of hydroxyl groups on the surface capable of oxidizing into carboxylic acids, a functional group capable of increasing ion exchange with mercury in solution. It was also expected that the impregnation of the MOF would increase the mercury removal; however, it was found that the functionalized fique achieved a greater percentage of removal, resulting in 81.33% of removal, 44% for the fique with the MOF-199 and 72% for the MOF-199-SH with. The pretreated fiber and raw also showed 74% and 56%, respectively, which indicates that fique does not require considerable modifications in its structure to achieve good performances. Even so, the functionalized fiber increases the percentage of removal considerably compared to the pretreated fique, which suggests that the functionalization process is a feasible procedure to apply with the purpose of improving the removal percentage. In addition, this is a procedure that follows a green approach since the reagents involved have low environmental impact, and the contribution to the remediation of natural resources is high.Keywords: biomass, nanotechnology, science materials, wastewater treatment
Procedia PDF Downloads 12010657 Building Transparent Supply Chains through Digital Tracing
Authors: Penina Orenstein
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In today’s world, particularly with COVID-19 a constant worldwide threat, organizations need greater visibility over their supply chains more than ever before, in order to find areas for improvement and greater efficiency, reduce the chances of disruption and stay competitive. The concept of supply chain mapping is one where every process and route is mapped in detail between each vendor and supplier. The simplest method of mapping involves sourcing publicly available data including news and financial information concerning relationships between suppliers. An additional layer of information would be disclosed by large, direct suppliers about their production and logistics sites. While this method has the advantage of not requiring any input from suppliers, it also doesn’t allow for much transparency beyond the first supplier tier and may generate irrelevant data—noise—that must be filtered out to find the actionable data. The primary goal of this research is to build data maps of supply chains by focusing on a layered approach. Using these maps, the secondary goal is to address the question as to whether the supply chain is re-engineered to make improvements, for example, to lower the carbon footprint. Using a drill-down approach, the end result is a comprehensive map detailing the linkages between tier-one, tier-two, and tier-three suppliers super-imposed on a geographical map. The driving force behind this idea is to be able to trace individual parts to the exact site where they’re manufactured. In this way, companies can ensure sustainability practices from the production of raw materials through the finished goods. The approach allows companies to identify and anticipate vulnerabilities in their supply chain. It unlocks predictive analytics capabilities and enables them to act proactively. The research is particularly compelling because it unites network science theory with empirical data and presents the results in a visual, intuitive manner.Keywords: data mining, supply chain, empirical research, data mapping
Procedia PDF Downloads 18010656 Design of Composite Joints from Carbon Fibre for Automotive Parts
Authors: G. Hemath Kumar, H. Mohit, K. Karthick
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One of the most important issues in the composite technology is the repairing of parts of aircraft structures which is manufactured from composite materials. In such applications and also for joining various composite parts together, they are fastened together either using adhesives or mechanical fasteners. The tensile strength of these joints was carried out using Universal Testing Machine (UTM). A parametric study was also conducted to compare the performance of the hybrid joint with varying adherent thickness, adhesive thickness and overlap length. The composition of the material is combination of epoxy resin and carbon fibre under the method of reinforcement. To utilize the full potential of composite materials as structural elements, the strength and stress distribution of these joints must be understood. The study of tensile strength in the members involved under various design conditions and various joints were took place.Keywords: carbon fiber, FRP composite, MMC, automotive
Procedia PDF Downloads 41310655 Biodegradation Study of a Biocomposite Material Based on Sunflower Oil and Alfa Fibers as Natural Resources
Authors: Sihem Kadem, Ratiba Irinislimane, Naima Belhaneche
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The natural resistance to biodegradation of polymeric materials prepared from petroleum-based source and the management of their wastes in the environment are the driving forces to replace them by other biodegradable materials from renewable resources. For that, in this work new biocomposites materials have been synthesis from sunflower oil (Helianthus annuus) and alfa plants (Stipatenacissima) as natural based resources. The sunflower oil (SFO) was chemically modified via epoxidation then acrylation reactions to obtain acrylated epoxidized sunflower oil resin (AESFO). The AESFO resin was then copolymerized with styrene as co-monomer in the presence of boron trifluoride (BF3) as cationic initiator and cobalt octoate (Co) as catalyst. The alfa fibers were treated with alkali treatment (5% NaOH) before been used as bio-reinforcement. Biocomposites were prepared by mixing the resin with untreated and treated alfa fibers at different percentages. A biodegradation study was carried out for the synthesized biocomposites in a solid medium (burial in the soil) by evaluated, first, the loss of mass, the results obtained were reached between 7.8% and 11% during one year. Then an observation under an optical microscope was carried out, after one year of burial in the soil, microcracks, brown and black spots were appeared on the samples surface. This results shows that the synthesized biocomposites have a great aptitude for biodegradation.Keywords: alfa fiber, biocomposite, biodegradation, soil, sunflower oil
Procedia PDF Downloads 16610654 Effect of Filler Metal Diameter on Weld Joint of Carbon Steel SA516 Gr 70 and Filler Metal SFA 5.17 in Submerged Arc Welding SAW
Authors: A. Nait Salah, M. Kaddami
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This work describes an investigation on the effect of filler metals diameter to weld joint, and low alloy carbon steel A516 Grade 70 is the base metal. Commercially SA516 Grade70 is frequently used for the manufacturing of pressure vessels, boilers and storage tank, etc. In fabrication industry, the hardness of the weld joint is between the important parameters to check, after heat treatment of the weld. Submerged arc welding (SAW) is used with two filler metal diameters, and this solid wire electrode is used for SAW non-alloy and for fine grain steels (SFA 5.17). The different diameters were selected (Ø = 2.4 mm and Ø = 4 mm) to weld two specimens. Both specimens were subjected to the same preparation conditions, heat treatment, macrograph, metallurgy micrograph, and micro-hardness test. Samples show almost similar structure with highest hardness. It is important to indicate that the thickness used in the base metal is 22 mm, and all specifications, preparation and controls were according to the ASME section IX. It was observed that two different filler metal diameters performed on two similar specimens demonstrated that the mechanical property (hardness) increases with decreasing diameter. It means that even the heat treatment has the same effect with the same conditions, the filler metal diameter insures a depth weld penetration and better homogenization. Hence, the SAW welding technique mentioned in the present study is favorable to implicate for the industry using the small filler metal diameter.Keywords: ASME, base metal, micro-hardness test, submerged arc welding
Procedia PDF Downloads 15610653 Characteristics of Acute Poisoning in Emergency Departments: Multicenter Study in Korea
Authors: Hyuk-Hoon Kim, Young Gi Min
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Background: Acute poisoning is the common cause of morbidity and mortality. Characteristics of acute poisoning differ between countries. While other countries operate the database system for poisoning, Korea has not collected the database for acute poisoning. Distribution of incidence of acute poisoning depending on the types of materials have also not studied in Korea. Our aims are to evaluate the etiologic and demographic characteristics of acute poisoning cases and to obtain up-to-date information on acute poisonings. Method: We retrospectively recorded cases of acute poisoning from eight emergency departments of second level or university hospitals from different cities in Gyeonggi province in Korea from April 2006 and March 2015. The distributions of incidence of acute poisoning depending on the types of materials are mapped by geographic information system. Result: A total of 3,449 poisoned cases were analyzed. Mean estimated age of patients was 39.56 ± 22.40 years. Mean male to female ratio of patients was 1:1.4. Mean proportion of intentional poisoning was 57.9%. Common materials are benzodiazepine (16.6%), carbon monoxide (10.5%), pesticide (8.1%) and zolpidem (7.1%) Common route of exposure is ingestion (79.5%) and followed by inhalation (16.5%). Common treatment methods are gastric lavage (20%) and activated charcoal (30%). Most cases had uneventful recovery; 61.4% were treated as outpatients and 0.1% of the poisoning resulted in death in ER. Conclusion: Even though the cases enrolled in our study is not the overall cases of acute poisoning in Korea, our study could be the basis of countermeasures for analysis and prevention of acute poisoning in Korea.Keywords: acute poisoning, emergency department, epidemiology, Korea
Procedia PDF Downloads 41110652 Healthcare Learning From Near Misses in Aviation Safety
Authors: Nick Woodier, Paul Sampson, Iain Moppett
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Background: For years, healthcare across the world has recognised that patients are coming to harm from the very processes meant to help them. In response, healthcare tells itself that it needs to ‘be more like aviation.’ Aviation safety is highly regarded by those in healthcare and is seen as an exemplar. Specifically, healthcare is keen to learn from how aviation uses near misses to make their industry safer. Healthcare is rife with near misses; however, there has been little progress addressing them, with most research having focused on reporting. Addressing the factors that contribute to near misses will potentially help reduce the number of significant, harm patientsafety incidents. While the healthcare literature states the need to learn from aviation’s use of near misses, there is nothing that describes how best to do this. The authors, as part of a larger study of near-miss management in healthcare, sought to learn from aviation to develop principles for how healthcare can identify, report, and learn from near misses to improve patient safety. Methods: A Grounded Theory (GT) methodology, augmented by a scoping review, was used. Data collection included interviews, field notes, and the literature. The review protocol is accessible online. The GT aimed to develop theories about how aviation, amongst other safety-critical industries, manages near misses. Results: Twelve aviation interviews contributed to the GT across passenger airlines, air traffic control, and bodies involved in policy, regulation, and investigation. The scoping review identified 83 articles across a range of safety-critical industries, but only seven focused on aviation. The GT identified that aviation interprets the term ‘near miss’ in different ways, commonly using it to specifically refer to near-miss air collisions, also known as Airproxes. Other types of near misses exist, such as health and safety, but the reporting of these and the safety climate associated with them is not as mature. Safety culture in aviation was regularly discussed, with evidence that culture varies depending on which part of the industry is being considered (e.g., civil vs. business aviation). Near misses are seen as just one part of an extensive safety management system, but processes to support their reporting and their analysis are not consistent. Their value alone is also questionable, with the challenge to long-held beliefs originating from the ‘common cause hypothesis.’ Conclusions: There is learning that healthcare can take from how parts of aviation manage and learn from near misses. For example, healthcare would benefit from a formal safety management system that currently does not exist. However, it may not be as simple as ‘healthcare should learn from aviation’ due to variation in safety maturity across the industry. Healthcare needs to clarify how to incorporate near misses into learning and whether allocating resources to them is of value; it was heard that catastrophes have led to greater improvements in safety in aviation.Keywords: aviation safety, patient safety, near miss, safety management systems
Procedia PDF Downloads 15610651 Stress Corrosion Crackings Test of Candidate Materials in Support of the Development of the European Small Modular Supercritical Water Cooled Rector Concept
Authors: Radek Novotny, Michal Novak, Daniela Marusakova, Monika Sipova, Hugo Fuentes, Peter Borst
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This research has been conducted within the European HORIZON 2020 project ECC-SMART. The main objective is to assess whether it is feasible to design and develop a small modular reactor (SMR) that would be cooled by supercritical water (SCW). One of the main objectives for material research concerns the corrosion of the candidate cladding materials. The experimental part has been conducted in support of the qualification procedure of the future SCW-SMR constructional materials. The last objective was to identify the gaps in current norms and guidelines. Apart from corrosion, resistance testing of candidate materials stresses corrosion cracking susceptibility tests have been performed in supercritical water. This paper describes part of these tests, in particular, those slow strain rate tensile loading applied for tangential ring shape specimens of two candidate materials, Alloy 800H and 310S stainless steel. These ring tensile tests are one the methods used for tensile testing of nuclear cladding. Here full circular heads with dimensions roughly equal to the inner diameter of the sample and the gage sections are placed in the parallel direction to the applied load. Slow strain rate tensile tests have been conducted in 380 or 500oC supercritical water applying two different elongation rates, 1x10-6 and 1x10-7 s-1. The effect of temperature and dissolved oxygen content on the SCC susceptibility of Alloy 800H and 310S stainless steel was investigated when two different temperatures and concentrations of dissolved oxygen were applied in supercritical water. The post-fracture analysis includes fractographic analysis of the fracture surfaces using SEM as well as cross-sectional analysis on the occurrence of secondary cracks. Assessment of the effect of environment and dissolved oxygen content was by comparing to the results of the reference tests performed in air and N2 gas overpressure. The effect of high temperature on creep and its role in the initiation of SCC was assessed as well. It has been concluded that the applied test method could be very useful for the investigation of stress corrosion cracking susceptibility of candidate cladding materials in supercritical water.Keywords: stress corrosion cracking, ring tensile tests, super-critical water, alloy 800H, 310S stainless steel
Procedia PDF Downloads 8910650 Decoupling Evaluation of Resource Consumption and Economic Development of Urban Industries under the View of Sustainable Development: The Case of Secondary and Tertiary Industries in Jiangsu Province, China
Authors: Jianghua Chen
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Sustainable urban development requires the coordination of economic growth and resource environment, and industrial transformation and upgrading is the key link. Based on the decoupling theory and the improved decoupling decomposition model, the quantitative evaluation and comprehensive analysis of the degree of decoupling between resource consumption and economic development in Jiangsu Province are conducted using the data related to the resource consumption and economic growth of the secondary and tertiary industries in Jiangsu Province from 2013 to 2018, as a way of exploring the sustainable development path of industrial transformation in Jiangsu Province. The results show that from the decoupling status, the degree of decoupling of economic development of the secondary industry to the required coke resources, water resources, and human resources is gradually deepening, and the decoupling index of economic development of the tertiary industry to the required water resources is fluctuating; from the perspective of the driving factors, the technological effect is the main driving factor to decouple the economic growth of Jiangsu Province to the resources, and the structural effect has a significant impact on the driving index of the decoupling of economic growth of the secondary and tertiary industries to the consumption of resources in Jiangsu Province. Finally, we discuss the difficulties of industrial transformation and layout faced by Jiangsu Province at present.Keywords: resource consumption, economic growth, industrial transformation, decoupling theory
Procedia PDF Downloads 3010649 Membrane Technologies for Obtaining Bioactive Fractions from Blood Main Protein: An Exploratory Study for Industrial Application
Authors: Fatima Arrutia, Francisco Amador Riera
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The meat industry generates large volumes of blood as a result of meat processing. Several industrial procedures have been implemented in order to treat this by-product, but are focused on the production of low-value products, and in many cases, blood is simply discarded as waste. Besides, in addition to economic interests, there is an environmental concern due to bloodborne pathogens and other chemical contaminants found in blood. Consequently, there is a dire need to find extensive uses for blood that can be both applicable to industrial scale and able to yield high value-added products. Blood has been recognized as an important source of protein. The main blood serum protein in mammals is serum albumin. One of the top trends in food market is functional foods. Among them, bioactive peptides can be obtained from protein sources by microbiological fermentation or enzymatic and chemical hydrolysis. Bioactive peptides are short amino acid sequences that can have a positive impact on health when administered. The main drawback for bioactive peptide production is the high cost of the isolation, purification and characterization techniques (such as chromatography and mass spectrometry) that make unaffordable the scale-up. On the other hand, membrane technologies are very suitable to apply to the industry because they offer a very easy scale-up and are low-cost technologies, compared to other traditional separation methods. In this work, the possibility of obtaining bioactive peptide fractions from serum albumin by means of a simple procedure of only 2 steps (hydrolysis and membrane filtration) was evaluated, as an exploratory study for possible industrial application. The methodology used in this work was, firstly, a tryptic hydrolysis of serum albumin in order to release the peptides from the protein. The protein was previously subjected to a thermal treatment in order to enhance the enzyme cleavage and thus the peptide yield. Then, the obtained hydrolysate was filtered through a nanofiltration/ultrafiltration flat rig at three different pH values with two different membrane materials, so as to compare membrane performance. The corresponding permeates were analyzed by liquid chromatography-tandem mass spectrometry technology in order to obtain the peptide sequences present in each permeate. Finally, different concentrations of every permeate were evaluated for their in vitro antihypertensive and antioxidant activities though ACE-inhibition and DPPH radical scavenging tests. The hydrolysis process with the previous thermal treatment allowed achieving a degree of hydrolysis of the 49.66% of the maximum possible. It was found that peptides were best transmitted to the permeate stream at pH values that corresponded to their isoelectric points. Best selectivity between peptide groups was achieved at basic pH values. Differences in peptide content were found between membranes and also between pH values for the same membrane. The antioxidant activity of all permeates was high compared with the control only for the highest dose. However, antihypertensive activity was best for intermediate concentrations, rather than higher or lower doses. Therefore, although differences between them, all permeates were promising regarding antihypertensive and antioxidant properties.Keywords: bioactive peptides, bovine serum albumin, hydrolysis, membrane filtration
Procedia PDF Downloads 20310648 Effect of Water Absorption on the Fatigue Behavior of Glass/Polyester Composite
Authors: Djamel Djeghader, Bachir Redjel
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The composite materials of glass fibers can be used as a repair material for damage elements under repeated stresses, and in various environments. A cyclic bending characterization of a glass/polyester composite material was carried out with consideration of the period of immersion in water. These tests describe the behavior of materials and identify the mechanical fatigue characteristics using the Wohler Curve for different immersion time: 0, 90, 180 and 270 days in water. These curves are characterized by a dispersion in the lifetimes were modeled by straight whose intercepts are very similar and comparable to the static strength. This material deteriorates fatigue at a constant rate, which increases with increasing immersion time in water at a constant speed. The endurance limit seems to be independent of the immersion time in the water.Keywords: fatigue, composite, glass, polyester, immersion, wohler
Procedia PDF Downloads 31810647 The Development of the Kamakhya Temple as a Historical Landmark in the Present State of Assam, India
Authors: Priyanka Tamta, Sukanya Sharma
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The Kamakhya Temple in Assam plays a very important role in the development of Assam as not only a historical place but also as an archaeologically important site. Temple building activity on the site began in 5th century AD when a cave temple dedicated to Lord Balabhadraswami was constructed here by King Maharajadhiraja Sri Surendra Varman. In the history of Assam, the name of this king is not found and neither the name of this form of Vishnu is known in this region. But this inscription sanctified the place as it recorded the first ever temple building activity in this region. The fifteen hundred years habitation history of the Kamakhya temple sites shows a gradual progression of the site from a religious site to an archaeological site and finally as a historical landmark. Here, in this paper, our main objective is to understand the evolution of Kamakhya temple site as a historical landscape and as an important landmark in the history of Assam. The central theme of the paper is the gradual development of the religious site to a historical landmark. From epigraphical records, it is known that the site received patronage from all ruling dynasties of Assam and its adjoining regions. Royal households of Kashmir, Nepal, Bengal, Orissa, Bihar, etc. have left their footprints on the site. According to records they donated wealth, constructed or renovated temples and participated in the overall maintenance of the deity. This made Kamakhya temple a ground of interaction of faiths, communities, and royalties of the region. Since the 5th century AD, there was a continuous struggle between different beliefs, faiths, and power on the site to become the dominant authority of the site. In the process, powerful beliefs system subsumed minor ones into a larger doctrine of beliefs. This can be seen in the case of the evolution of the Kamakhya temple site as one of the important Shakta temples in India. Today, it is cultural identity marker of the state of Assam within which it is located. Its diverse faiths and beliefs have been appropriated by powerful legends to the dominant faith of the land. The temple has evolved from a cave temple to a complex of seventeen temples. The faith has evolved from the worship of water, an element of nature to the worship of the ten different forms of the goddess with their five male consorts or Bhairavas. Today, it represents and symbolizes the relationship of power and control out of which it has emerged. During different periods of occupation certain architectural and iconographical characters developed which indicated diffusion and cultural adaptation. Using this as sources and the epigraphical records this paper will analyze the interactive and dynamic processes which operated in the building of this cultural marker, the archaeological site of Kamakhya.Keywords: cultural adaptation and diffusion, cultural and historical landscape, Kamakhya, Saktism, temple art and architecture, historiography
Procedia PDF Downloads 25310646 Study of Parking Demand for Offices – Case Study: Kolkata
Authors: Sanghamitra Roy
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In recent times, India has experienced the phenomenal rise in the number of registered vehicles and vehicular trips, particularly intra-city trips in most of its urban areas. The increase in vehicle ownership and use have increased parking demand immensely and accommodating the same is now a matter of big concern. Most cities do not have adequate off-street parking facilities thus forcing people to park on the streets. This has resulted in decreased carrying capacity, decreased traffic speed, increased congestion, and increased environmental problems. While integrated multi-modal transportation system is the answer to such problems, parking issues will continue to exist. In Kolkata, only 6.4% land is devoted for roads. The consequences of this huge crunch in road spaces coupled with increased parking demand are severe particularly in the CBD and major commercial areas, making the role of off-street parking facilities in Kolkata even more critical. To meaningfully address parking issues, it is important to identify the factors that influence parking demand so that it can be assessed and comprehensive parking policies and plans for the city can be formulated. This paper aims at identifying the factors that contribute towards parking demand for offices in Kolkata and their degree of correlation with parking demand. The study is limited to home-to-work trips located within Kolkata Municipal Corporation (KMC) where parking related issues are most pronounced. The data for the study is collected through personal interviews, questionnaires and direct observations from offices across the wards of KMC. SPSS is used for classification of the data and analyses of the same. The findings of this study will help in re-assessment of the parking requirements specified in The Kolkata Municipal Corporation Building Rules as a step towards alleviating parking related issues in the city.Keywords: building rules, office spaces, parking demand, urbanization
Procedia PDF Downloads 31810645 'Sex, Work and Sex-Work': The Clandestine Tale of a Tabooed Industry in Bangladesh
Authors: Parvez Sattar
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There are around 150,000 female sex workers in Bangladesh, and the country hosts one of the largest brothels in the world. There are 20 brothel-villages in the country, of which 14 are recognized to be ‘official’, and at least 11 are currently operational. Although the national Constitution adopts a preventive policy against prostitution, law does not, as such, prohibit commercial sex work by an adult woman working in a brothel having made an affidavit in this regard. But, at the same time, the law renders at least some forms of floating and hotel based sex work illegal, while sex between males has been termed as sodomy and made culpable offence even on its own. All forms of sex works by MSM and Hijra are thus branded as criminal acts. Observations and findings drawn in this article are based on both primary and secondary sources collecting data from a series of field-based empirical studies conducted by the author through questionnaire survey, FGDs, key informant consultations and other PRA/PLA tools. General and specific conclusions have been based on analysis guided by international standards of human and labour rights approaches. It has been noted that neither the community attitudes nor the cultural mind-sets, or the State's institutional set up is supportive of the causes of sex workers engaged in the most exploitative forms of labour. Lack of respect for fundamental rights continues to diminish any chances of sex workers' reintegration to the mainstream of the society, perpetuates poverty, and increases their vulnerability to HIV/AIDS. To aggravate the scenario, the endemic practice of a complex debt-bondage masked by the so-called 'entry-cost' and ‘legal license’ to the industry is considered to be a somewhat accepted 'open secret' and that the police and administration keep their eyes off from such practices treating these as 'their internal affairs'. Often these practices are used by the Sardarni/Khala (landlady) and other 'managing' actors as the tool for further exploitation of the sex workers as well as a 'control strategy'. The paper concludes with the observation that the tabooed truths of commercial sex and sex workers are inherently embedded in the very factors that compel them into this endemically ostracised profession itself. While denial of both recognition and enjoyment of the fundamental human rights of sex workers is widespread, it is the same cycle of social vulnerability and economic exclusion that often confines these people within a continuous process of servitude and modern day slavery.Keywords: commercial sex work and human rights, Labor protection in sex industry, Prostitution Law in Bangladesh, Sex work as modern day slavery
Procedia PDF Downloads 11210644 The Effect of Rice Husk Ash on the Mechanical and Durability Properties of Concrete
Authors: Binyamien Rasoul
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Portland cement is one of the most widely used construction materials in the world today; however, manufacture of ordinary Portland cement (OPC) emission significant amount of CO2 resulting environmental impact. On the other hand, rice husk ash (RHA), which is produce as by product material is generally considered to be an environmental issue as a waste material. This material (RHA) consists of non-crystalline silicon dioxide with high specific surface area and high pozzolanic reactivity. These RHA properties can demonstrate a significant influence in improving the mechanical and durability properties of mortar and concrete. Furthermore, rice husk ash can provide a cost effective and give concrete more sustainability. In this paper, chemical composition, reactive silica and fineness effect was assessed by examining five different types of RHA. Mortars and concrete specimens were molded with 5% to 50% of ash, replacing the Portland cement, and measured their compressive and tensile strength behavior. Beyond it, another two parameters had been considered: the durability of concrete blended RHA, and effect of temperature on the transformed of amorphous structure to crystalline form. To obtain the rice husk ash properties, these different types were subjected to X-Ray fluorescence to determine the chemical composition, while pozzolanic activity obtained by using X-Ray diffraction test. On the other hand, finesses and specific surface area were obtained by used Malvern Mastersizer 2000 test. The measured parameters properties of fresh mortar and concrete obtained by used flow table and slump test. While, for hardened mortar and concrete the compressive and tensile strength determined pulse the chloride ions penetration for concrete using NT Build 492 (Nord Test) – non-steady state migration test (RMT Test). The obtained test results indicated that RHA can be used as a cement replacement material in concrete with considerable proportion up to 50% percentages without compromising concrete strength. The use of RHA in the concrete as blending materials improved the different characteristics of the concrete product. The paper concludes that to exhibits a good compressive strength of OPC mortar or concrete with increase RHA replacement ratio rice husk ash should be consist of high silica content with high pozzolanic activity. Furthermore, with high amount of carbon content (12%) could be improve the strength of concrete when the silica structure is totally amorphous. As well RHA with high amount of crystalline form (25%) can be used as cement replacement when the silica content over 90%. The workability and strength of concrete increased by used of superplasticizer and it depends on the silica structure and carbon content. This study therefore is an investigation of the effect of partially replacing Ordinary Portland cement (OPC) with Rice hush Ash (RHA) on the mechanical properties and durability of concrete. This paper gives satisfactory results to use RHA in sustainable construction in order to reduce the carbon footprint associated with cement industry.Keywords: OPC, ordinary Portland cement, RHA rice husk ash, W/B water to binder ratio, CO2, carbon dioxide
Procedia PDF Downloads 19510643 Specific Earthquake Ground Motion Levels That Would Affect Medium-To-High Rise Buildings
Authors: Rhommel Grutas, Ishmael Narag, Harley Lacbawan
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Construction of high-rise buildings is a means to address the increasing population in Metro Manila, Philippines. The existence of the Valley Fault System within the metropolis and other nearby active faults poses threats to a densely populated city. The distant, shallow and large magnitude earthquakes have the potential to generate slow and long-period vibrations that would affect medium-to-high rise buildings. Heavy damage and building collapse are consequences of prolonged shaking of the structure. If the ground and the building have almost the same period, there would be a resonance effect which would cause the prolonged shaking of the building. Microzoning the long-period ground response would aid in the seismic design of medium to high-rise structures. The shear-wave velocity structure of the subsurface is an important parameter in order to evaluate ground response. Borehole drilling is one of the conventional methods of determining shear-wave velocity structure however, it is an expensive approach. As an alternative geophysical exploration, microtremor array measurements can be used to infer the structure of the subsurface. Microtremor array measurement system was used to survey fifty sites around Metro Manila including some municipalities of Rizal and Cavite. Measurements were carried out during the day under good weather conditions. The team was composed of six persons for the deployment and simultaneous recording of the microtremor array sensors. The instruments were laid down on the ground away from sewage systems and leveled using the adjustment legs and bubble level. A total of four sensors were deployed for each site, three at the vertices of an equilateral triangle with one sensor at the centre. The circular arrays were set up with a maximum side length of approximately four kilometers and the shortest side length for the smallest array is approximately at 700 meters. Each recording lasted twenty to sixty minutes. From the recorded data, f-k analysis was applied to obtain phase velocity curves. Inversion technique is applied to construct the shear-wave velocity structure. This project provided a microzonation map of the metropolis and a profile showing the long-period response of the deep sedimentary basin underlying Metro Manila which would be suitable for local administrators in their land use planning and earthquake resistant design of medium to high-rise buildings.Keywords: earthquake, ground motion, microtremor, seismic microzonation
Procedia PDF Downloads 46910642 Research on the Planning Spatial Mode of China's Overseas Industrial Park
Authors: Sidong Zhao, Xingping Wang
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Recently, the government of China has provided strong support the developments of overseas industrial parks. The global distribution of China overseas industrial parks has gradually moved from the 'sparks of fire' to the 'prairie fires.' The support and distribution have promoted developing overseas industrial parks to a strategy of constructing a China's new open economic system and a typical representative of the 'Chinese wisdom' and the 'China's plans' that China has contributed to the globalization of the new era under the initiative of the Belt and Road. As the industrial parks are the basis of 'work/employment', a basic function of a city (Athens Constitution), planning for developments of industrial parks has become a long-term focus of urban planning. Based on the research of the planning and the analysis of the present developments of some typical China overseas industrial parks, we found some interesting rules: First, large numbers of the China overseas industrial parks are located in less developed countries. These industrial parks have become significant drives of the developments of the host cities and even the regions in those countries, especially in investment, employment and paid tax fee for the local, etc. so, the planning and development of overseas industrial parks have received extensive attention. Second, there are some problems in the small part of the overseas Park, such as the planning of the park not following the planning of the host city and lack of implementation of the park planning, etc. These problems have led to the difficulties of the implementation of the planning and the sustainable developments of the parks. Third, a unique pattern of space development has been formed. in the dimension of the patterns of regional spatial distribution, there are five characteristics - along with the coast, along the river, along with the main traffic lines and hubs, along with the central urban area and along the connections of regions economic. In the dimension of the spatial relationships between the industrial park and the city, there is a growing and evolving trend as 'separation – integration - union'. In the dimension of spatial mode of the industrial parks, there are different patterns of development, such as a specialized industrial park, complex industrial park, characteristic town and new urban area of industry, etc. From the perspective of the trends of the developments and spatial modes, in the future, the planning of China overseas industrial parks should emphasize the idea of 'building a city based on the industrial park'. In other words, it's making the developments of China overseas industrial parks move from 'driven by policy' to 'driven by the functions of the city', accelerating forming the system of China overseas industrial parks and integrating the industrial parks and the cities.Keywords: overseas industrial park, spatial mode, planning, China
Procedia PDF Downloads 20610641 A Study of the Relationship among the Hotel Staff's Work Stress, Perceived Organizational Support, and Work Efficacy: A Case Study of Macao
Authors: Zhang Tao, Si Tang, Zhang Yufeng, Jin Jiahua
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Work pressure is an emerging research of organizational behavior. Many factors associated with this study also attracted the interest of scholars. Macao is surrounding by open micro-capitalist economy which has a high internationalization level and Mature operation system. And there is no doubt that tourism and hotel service industry is the pillar of the Macao economy with the developing of the mainland individual tourist visa. More and more cities are willing to inclusive culture diversity which lead to the amount of inbound tourists present high-speed up trend cause the hotel industry has a strong customer base and development space. At the same time, the hotel staff is an important role in the service. However, affected by some adverse factors, the hotel staff face a variety of pressures. This study combs the concept and theory of pressures relevant influencing factors and puts forward the purpose of this research. The focus of this study will be organizational supported by work efficiency and work pressure, using qualitative and quantitative research methods. Through questionnaires and interviews, 10 hotels in Macao were selected and 500 questionnaires were distributed to the employees. Statistical analysis software SPSS was used for descriptive statistics. By exploratory factor analysis and confirmatory factor analysis, effect. And the relevant practitioners on behalf of the interview content analysis. The innovation of this research lies in the empirical study of the relationship between the working pressure, organizational support and working efficiency of Macau hotel practitioners, and constructs and validates the structural model of the relationship among them. This model will be helpful for people to use more research methods to study hotel practitioners pressure in the future. At the same time, we can draw the following conclusions: 1. There is a significant negative correlation between salary level and job stress; 2. There is a significant negative correlation between job stress and performance; 3. Different organizational support can interfere the relationship between job stress and performance; 4. Put forward the strategy of relevance adjustment, which provides a reference value for the hotel industry in human resource management. It would be helpful to improve their service standard by training their practitioners more scientifically and rationally.Keywords: Macau, perceived organizational support, work stress, work efficiency
Procedia PDF Downloads 25010640 Analyzing the Effects of Bio-fibers on the Stiffness and Strength of Adhesively Bonded Thermoplastic Bio-fiber Reinforced Composites by a Mixed Experimental-Numerical Approach
Authors: Sofie Verstraete, Stijn Debruyne, Frederik Desplentere
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Considering environmental issues, the interest to apply sustainable materials in industry increases. Specifically for composites, there is an emerging need for suitable materials and bonding techniques. As an alternative to traditional composites, short bio-fiber (cellulose-based flax) reinforced Polylactic Acid (PLA) is gaining popularity. However, these thermoplastic based composites show issues in adhesive bonding. This research focusses on analyzing the effects of the fibers near the bonding interphase. The research applies injection molded plate structures. A first important parameter concerns the fiber volume fraction, which directly affects adhesion characteristics of the surface. This parameter is varied between 0 (pure PLA) and 30%. Next to fiber volume fraction, the orientation of fibers near the bonding surface governs the adhesion characteristics of the injection molded parts. This parameter is not directly controlled in this work, but its effects are analyzed. Surface roughness also greatly determines surface wettability, thus adhesion. Therefore, this research work considers three different roughness conditions. Different mechanical treatments yield values up to 0.5 mm. In this preliminary research, only one adhesive type is considered. This is a two-part epoxy which is cured at 23 °C for 48 hours. In order to assure a dedicated parametric study, simple and reproduceable adhesive bonds are manufactured. Both single lap (substrate width 25 mm, thickness 3 mm, overlap length 10 mm) and double lap tests are considered since these are well documented and quite straightforward to conduct. These tests are conducted for the different substrate and surface conditions. Dog bone tensile testing is applied to retrieve the stiffness and strength characteristics of the substrates (with different fiber volume fractions). Numerical modelling (non-linear FEA) relates the effects of the considered parameters on the stiffness and strength of the different joints, obtained through the abovementioned tests. Ongoing work deals with developing dedicated numerical models, incorporating the different considered adhesion parameters. Although this work is the start of an extensive research project on the bonding characteristics of thermoplastic bio-fiber reinforced composites, some interesting results are already prominent. Firstly, a clear correlation between the surface roughness and the wettability of the substrates is observed. Given the adhesive type (and viscosity), it is noticed that an increase in surface energy is proportional to the surface roughness, to some extent. This becomes more pronounced when fiber volume fraction increases. Secondly, ultimate bond strength (single lap) also increases with increasing fiber volume fraction. On a macroscopic level, this confirms the positive effect of fibers near the adhesive bond line.Keywords: adhesive bonding, bio-fiber reinforced composite, flax fibers, lap joint
Procedia PDF Downloads 13010639 Loading and Unloading Scheduling Problem in a Multiple-Multiple Logistics Network: Modelling and Solving
Authors: Yasin Tadayonrad
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Most of the supply chain networks have many nodes starting from the suppliers’ side up to the customers’ side that each node sends/receives the raw materials/products from/to the other nodes. One of the major concerns in this kind of supply chain network is finding the best schedule for loading /unloading the shipments through the whole network by which all the constraints in the source and destination nodes are met and all the shipments are delivered on time. One of the main constraints in this problem is loading/unloading capacity in each source/ destination node at each time slot (e.g., per week/day/hour). Because of the different characteristics of different products/groups of products, the capacity of each node might differ based on each group of products. In most supply chain networks (especially in the Fast-moving consumer goods industry), there are different planners/planning teams working separately in different nodes to determine the loading/unloading timeslots in source/destination nodes to send/receive the shipments. In this paper, a mathematical problem has been proposed to find the best timeslots for loading/unloading the shipments minimizing the overall delays subject to respecting the capacity of loading/unloading of each node, the required delivery date of each shipment (considering the lead-times), and working-days of each node. This model was implemented on python and solved using Python-MIP on a sample data set. Finally, the idea of a heuristic algorithm has been proposed as a way of improving the solution method that helps to implement the model on larger data sets in real business cases, including more nodes and shipments.Keywords: supply chain management, transportation, multiple-multiple network, timeslots management, mathematical modeling, mixed integer programming
Procedia PDF Downloads 9810638 UV Resistibility of a Carbon Nanofiber Reinforced Polymer Composite
Authors: A. Evcin, N. Çiçek Bezir, R. Duman, N. Duman
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Nowadays, a great concern is placed on the harmfulness of ultraviolet radiation (UVR) which attacks human bodies. Nanocarbon materials, such as carbon nanotubes (CNTs), carbon nanofibers (CNFs) and graphene, have been considered promising alternatives to shielding materials because of their excellent electrical conductivities, very high surface areas and low densities. In the present work, carbon nanofibers have been synthesized from solutions of Polyacrylonitrile (PAN)/ N,N-dimethylformamide (DMF) by electrospinning method. The carbon nanofibers have been stabilized by oxidation at 250 °C for 2 h in air and carbonized at 750 °C for 1 h in H2/N2. We present the fabrication and characterization of transparent and ultraviolet (UV) shielding CNF/polymer composites. The content of CNF filler has been varied from 0.2% to 0.6 % by weight. UV Spectroscopy has been performed to study the effect of composition on the transmittance of polymer composites.Keywords: electrospinning, carbon nanofiber, characterization, composites, nanofiber, ultraviolet radiation
Procedia PDF Downloads 23010637 3D Numerical Study of Tsunami Loading and Inundation in a Model Urban Area
Authors: A. Bahmanpour, I. Eames, C. Klettner, A. Dimakopoulos
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We develop a new set of diagnostic tools to analyze inundation into a model district using three-dimensional CFD simulations, with a view to generating a database against which to test simpler models. A three-dimensional model of Oregon city with different-sized groups of building next to the coastline is used to run calculations of the movement of a long period wave on the shore. The initial and boundary conditions of the off-shore water are set using a nonlinear inverse method based on Eulerian spatial information matching experimental Eulerian time series measurements of water height. The water movement is followed in time, and this enables the pressure distribution on every surface of each building to be followed in a temporal manner. The three-dimensional numerical data set is validated against published experimental work. In the first instance, we use the dataset as a basis to understand the success of reduced models - including 2D shallow water model and reduced 1D models - to predict water heights, flow velocity and forces. This is because models based on the shallow water equations are known to underestimate drag forces after the initial surge of water. The second component is to identify critical flow features, such as hydraulic jumps and choked states, which are flow regions where dissipation occurs and drag forces are large. Finally, we describe how future tsunami inundation models should be modified to account for the complex effects of buildings through drag and blocking.Financial support from UCL and HR Wallingford is greatly appreciated. The authors would like to thank Professor Daniel Cox and Dr. Hyoungsu Park for providing the data on the Seaside Oregon experiment.Keywords: computational fluid dynamics, extreme events, loading, tsunami
Procedia PDF Downloads 11810636 Investigation of Compressive Strength of Slag-Based Geopolymer Concrete Incorporated with Rice Husk Ash Using 12M Alkaline Activator
Authors: Festus A. Olutoge, Ahmed A. Akintunde, Anuoluwapo S. Kolade, Aaron A. Chadee, Jovanca Smith
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Geopolymer concrete's (GPC) compressive strength was investigated. The GPC was incorporated with rice husk ash (RHA) and ground granulated blast furnace slag (GGBFS), which may have potential in the construction industry to replace Portland limestone cement (PLC) concrete. The sustainable construction binders used were GGBFS and RHA, and a solution of sodium hydroxide (NaOH) and sodium silicate gel (Na₂SiO₃) was used as the 12-molar alkaline activator. Five GPC mixes comprising fine aggregates, coarse aggregates, GGBS, and RHA, and the alkaline solution in the ratio 2: 2.5: 1: 0.5, respectively, were prepared to achieve grade 40 concrete, and PLC was wholly substituted with GGBFS and RHA in the ratios of 0:100, 25:75, 50:50, 75:25, and 100:0. A control mix was also prepared which comprised of 100% water and 100% PLC as the cementitious material. The GPC mixes were thermally cured at 60-80ºC in an oven for approximately 24hrs. After curing for 7 and 28 days, the compressive strength test results of the hardened GPC samples showed that GPC-Mix #3, comprising 50% GGBFS and 50% RHA, was the most efficient geopolymer mix. The mix had compressive strengths of 35.71MPa and 47.26MPa, 19.87% and 8.69% higher than the PLC concrete samples, which had 29.79MPa and 43.48MPa after 7 and 28 days, respectively. Therefore, geopolymer concrete containing GGBFS incorporated with RHA is an efficient method of decreasing the use of PLC in conventional concrete production and reducing the high amounts of CO₂ emitted into the atmosphere in the construction industry.Keywords: alkaline solution, cementitious material, geopolymer concrete, ground granulated blast furnace slag, rice husk ash
Procedia PDF Downloads 11710635 The Role of Semi Open Spaces on Exploitation of Wind-Driven Ventilation
Authors: Paria Saadatjoo
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Given that HVAC systems are the main sources of carbon dioxide producers, developing ways to reduce dependence on these systems and making use of natural resources is too important to achieve environmentally friendly buildings. A major part of building potential in terms of using natural energy resources depends on its physical features. So architectural decisions at the first step of the design process can influence the building's energy efficiency significantly. Implementation of semi-open spaces into solid apartment blocks inspired by the concept of courtyard in ancient buildings as a passive cooling strategy is currently enjoying great popularity. However, the analysis of these features and their effect on wind behavior at initial design steps is a difficult task for architects. The main objective of this research was to investigate the influence of semi-open to closed space ratio on airflow patterns in and around midrise buildings and introduce the best ratio in terms of harnessing natural ventilation. The main strategy of this paper was semi-experimental, and the research methodology was descriptive statistics. At the first step, by changing the terrace area, 6 models with various open to closed space ratios were created. These forms were then transferred to CFD software to calculate the primary indicators of natural ventilation potentials such as wind force coefficient, air flow rate, age of air distribution, etc. Investigations indicated that modifying the terrace area and, in other words, the open to closed space ratio influenced the wind force coefficient, airflow rate, and age of air distribution.Keywords: natural ventilation, wind, midrise, open space, energy
Procedia PDF Downloads 17310634 Numerical Investigation of Thermal Energy Storage System with Phase Change Materials
Authors: Mrityunjay Kumar Sinha, Mayank Srivastava
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The position of interface and temperature variation of phase change thermal energy storage system under constant heat injection and radiative heat injection is analysed during charging/discharging process by Heat balance integral method. The charging/discharging process is solely governed by conduction. Phase change material is kept inside a rectangular cavity. Time-dependent fixed temperature and radiative boundary condition applied on one wall, all other walls are thermally insulated. Interface location and temperature variation are analysed by using MATLAB.Keywords: conduction, melting/solidification, phase change materials, Stefan’s number
Procedia PDF Downloads 39710633 Supply Chain Optimization for Silica Sand in a Glass Manufacturing Company
Authors: Ramon Erasmo Verdin Rodriguez
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Many has been the ways that historically the managers and gurus has been trying to get closer to the perfect supply chain, but since this topic is so vast and very complex the bigger the companies are, the duty has not been certainly easy. On this research, you are going to see thru the entrails of the logistics that happens at a glass manufacturing company with the number one raw material of the process that is the silica sand. After a very quick passage thru the supply chain, this document is going to focus on the way that raw materials flow thru the system, so after that, an analysis and research can take place to improve the logistics. Thru Operations Research techniques, it will be analyzed the current scheme of distribution and inventories of raw materials at a glass company’s plants, so after a mathematical conceptualization process, the supply chain could be optimized with the purpose of reducing the uncertainty of supply and obtaining an economic benefit at the very end of this research.Keywords: inventory management, operations research, optimization, supply chain
Procedia PDF Downloads 32910632 A Study on the Effectiveness of Alternative Commercial Ventilation Inlets That Improve Energy Efficiency of Building Ventilation Systems
Authors: Brian Considine, Aonghus McNabola, John Gallagher, Prashant Kumar
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Passive air pollution control devices known as aspiration efficiency reducers (AER) have been developed using aspiration efficiency (AE) concepts. Their purpose is to reduce the concentration of particulate matter (PM) drawn into a building air handling unit (AHU) through alterations in the inlet design improving energy consumption. In this paper an examination is conducted into the effect of installing a deflector system around an AER-AHU inlet for both a forward and rear-facing orientations relative to the wind. The results of the study found that these deflectors are an effective passive control method for reducing AE at various ambient wind speeds over a range of microparticles of varying diameter. The deflector system was found to induce a large wake zone at low ambient wind speeds for a rear-facing AER-AHU, resulting in significantly lower AE in comparison to without. As the wind speed increased, both contained a wake zone but have much lower concentration gradients with the deflectors. For the forward-facing models, the deflector system at low ambient wind speed was preferred at higher Stokes numbers but there was negligible difference as the Stokes number decreased. Similarly, there was no significant difference at higher wind speeds across the Stokes number range tested. The results demonstrate that a deflector system is a viable passive control method for the reduction of ventilation energy consumption.Keywords: air handling unit, air pollution, aspiration efficiency, energy efficiency, particulate matter, ventilation
Procedia PDF Downloads 12310631 Numerical Study of Bubbling Fluidized Beds Operating at Sub-atmospheric Conditions
Authors: Lanka Dinushke Weerasiri, Subrat Das, Daniel Fabijanic, William Yang
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Fluidization at vacuum pressure has been a topic that is of growing research interest. Several industrial applications (such as drying, extractive metallurgy, and chemical vapor deposition (CVD)) can potentially take advantage of vacuum pressure fluidization. Particularly, the fine chemical industry requires processing under safe conditions for thermolabile substances, and reduced pressure fluidized beds offer an alternative. Fluidized beds under vacuum conditions provide optimal conditions for treatment of granular materials where the reduced gas pressure maintains an operational environment outside of flammability conditions. The fluidization at low-pressure is markedly different from the usual gas flow patterns of atmospheric fluidization. The different flow regimes can be characterized by the dimensionless Knudsen number. Nevertheless, hydrodynamics of bubbling vacuum fluidized beds has not been investigated to author’s best knowledge. In this work, the two-fluid numerical method was used to determine the impact of reduced pressure on the fundamental properties of a fluidized bed. The slip flow model implemented by Ansys Fluent User Defined Functions (UDF) was used to determine the interphase momentum exchange coefficient. A wide range of operating pressures was investigated (1.01, 0.5, 0.25, 0.1 and 0.03 Bar). The gas was supplied by a uniform inlet at 1.5Umf and 2Umf. The predicted minimum fluidization velocity (Umf) shows excellent agreement with the experimental data. The results show that the operating pressure has a notable impact on the bed properties and its hydrodynamics. Furthermore, it also shows that the existing Gorosko correlation that predicts bed expansion is not applicable under reduced pressure conditions.Keywords: computational fluid dynamics, fluidized bed, gas-solid flow, vacuum pressure, slip flow, minimum fluidization velocity
Procedia PDF Downloads 143