Search results for: family led decision making
2175 Early Screening of Risk Ergonomics among Workers at Madura's Batik Industrial: Rapid Entire Body Assessment and Quick Exposure Checklist
Authors: Abdul Kadir, L. Meily Kurniawidjaja
Abstract:
Batik Madura workers are exposed to many Musculoskeletal Disorders risk factors, particularly Low Back Pain (LBP). This study was conducted as an early detection of ergonomic risk level on Workers Industrial Sentra Batik Madura in Dusun Banyumas, Klampar Subdistrict, Proppo Pamekasan, Madura, East Java. This study includes 12 workers who 11 workers had pain in the upper and lower part of the neck, back, wrist right hand, also 10 workers had pain in the right shoulder. This is a descriptive observational study with cross-sectional approach. Qualitative research by observing workers activity such as draw and putting the wax motif, fabric dyeing, fabric painting, discoloration, washing, and drying. The results are workers have identified ergonomic hazards such as awkward postures, twisting movements, repetitive, and static work postures. Using the method of REBA and QEC, the results get a very high-risk level of activity in each of Madura batik making process is the draw and putting the wax motif, coloring, painting, discoloration, washing, and drying. The level of risk can be reduced by improvement of work equipment include the provision of seats, strut fabric, high settings furnaces, drums, coloring basin, and washing tub.Keywords: activities of Madura's batik, ergonomic risk level, equipment, QEC (Quick Exposure Checklist), REBA (Rapid Entire Body Assessment)
Procedia PDF Downloads 1942174 The Use of Microalgae Cultivation for Improving the Effluent Behavior of Anaerobic Digestion of Food Wastes at Psychrophilic Range
Authors: Pedro M. Velasco, Cecilia C. Alday, Oscar C. Avello, Ximena T. Faundez, Luis M. Velasco
Abstract:
Anaerobic digestion (AD) plants of food waste (FW) produced by agro-industry, have been widely developed from last decade to nowadays, because of the advantages over aerobic active sludge systems. Despite several bioreactor configurations and operation modes have been successfully improved and implemented at industrial scale in a wide range of applications, effluent behavior, after AD, does not commonly meet requirements for direct disposal into the environment without further treatments. In addition, literature has rarely shown AD of food waste at psychrophilic range. This temperature range may be of interest for making AD plant operation easier and increasing the stability of digestion. In spite of literature shows several methods for post-treatment, such as the use of microalgae, these have not been cultivated on effluents from AD at psychrophilic range. Hence, with the aim of showing the potential use of AD of FW at the psychrophilic range (25ºC) and the viability of microalgae post-treatment, single batch reactors have been used for methane potential tests at laboratory scale. Afterwards, digestates, derived from this AD of FW sludge, were diluted with fresh water at different ratios (1:0, 1:1; 1:4) and used as culture media for photoautotrophic microalgae. Several parameters, such as pH, biogas production, and chemical oxygen demand, were measured periodically over several months. Results show that methane potential is 150 ml g-1 per volatile solid with up to 57.7 % of methane content. Moreover, microalgae has been successfully cultivated on all tested effluents and in case of 1:1 and 1:4 rates, the resulting effluents meet the quality levels required for irrigation water.Keywords: anaerobic digestion, biogas, food waste, microalgae, psychrophilic range
Procedia PDF Downloads 3042173 Tectono-Thermal Evolution of Ningwu-Jingle Basin in North China Craton: Constraints from Apatite (U–Th-Sm)/He and Fission Track Thermochronology
Authors: Zhibin Lei, Minghui Yang
Abstract:
Ningwu-Jingle basin is a structural syncline which has undergone a complex tectono-thermal history since Cretaceous. It stretches along the strike of the northern Lvliang Mountains which are the most important mountains in the middle and west of North China Craton. The Mesozoic units make up of the core of Ningwu-Jingle Basin, with pre-Mesozoic units making up of its flanks. The available low-temperature thermochronology implies that Ningwu-Jingle Basin has experienced two stages of uplifting: 94±7Ma to 111±8Ma (Albian to Cenomanian) and 62±4 to 75±5Ma (Danian to Maastrichtian). In order to constrain its tectono-thermal history in the Cenozoic, both apatite (U-Th-Sm)/He and fission track dating analysis are applied on 3 Middle Jurassic and 3 Upper Triassic sandstone samples. The central fission track ages range from 74.4±8.8Ma to 66.0±8.0Ma (Campanian to Maastrichtian) which matches well with previous data. The central He ages range from 20.1±1.2Ma to 49.1±3.0Ma (Ypresian to Burdigalian). Inverse thermal modeling is established based on both apatite fission track data and (U-Th-Sm)/He data. The thermal history obtained reveals that all 6 sandstone samples cross the high-temperature limit of fission track partial annealing zone by the uppermost Cretaceous and that of He partial retention zone by the uppermost Eocene to the early Oligocene. The result indicates that the middle and west of North China Craton is not stable in the Cenozoic.Keywords: apatite fission track thermochronology, apatite (u–th)/he thermochronology, Ningwu-Jingle basin, North China craton, tectono-thermal history
Procedia PDF Downloads 2622172 When Digital Innovation Augments Cultural Heritage: An Innovation from Tradition Story
Authors: Danilo Pesce, Emilio Paolucci, Mariolina Affatato
Abstract:
Looking at the future and at the post-digital era, innovations commonly tend to dismiss the old and replace it with the new. The aim of this research is to study the role that digital innovation can play alongside the information chain within the traditional sectors and the subsequent value creation opportunities that actors and stakeholders can exploit. By drawing on a wide body of literature on innovation and strategic management and by conducting a case study on the cultural heritage industry, namely Google Arts & Culture, this study shows that technology augments complements, and amplifies the way people experience their cultural interests and experience. Furthermore, the study shows a process of democratization of art since museums can exploit new digital and virtual ways to distribute art globally. Moreover, new needs arose from the 2020 pandemic that hit and forced the world to a state of cultural fasting and caused a radical transformation of the paradigm online vs. onsite. Finally, the study highlights the capabilities that are emerging at different stages of the value chain, owing to the technological innovation available in the market. In essence, this research underlines the role of Google in allowing museums to reach users worldwide, thus unlocking new mechanisms of value creation in the cultural heritage industry. Likewise, this study points out how Google provides value to users by means of increasing the provision of artworks, improving the audience engagement and virtual experience, and providing new ways to access the online contents. The paper ends with a discussion of managerial and policy-making implications.Keywords: big data, digital platforms, digital transformation, digitization, Google Arts and Culture, stakeholders’ interests
Procedia PDF Downloads 1572171 Influence of CA, SR and BA Substitution on lafeo3Performances During Chemical Looping Processes
Authors: Rong Sun, Laihong Shen
Abstract:
La-based perovskite oxygen carriers, especially the doped-La(M)FeO₃, showed excellent performances during chemical looping processes. However, the mechanisms of the undoped and doped La(M)FeO₃ are not clear at present, making the mechanisms clear may help the development of chemical looping technologies. In this paper, the method based on the density function theory (DFT) was used to analysis the influence of Ca, Sr, and Ba doping of La on the electronic structure, while the CO oxidation mechanisms on the surface of LaFeO₃ and Ca-doped LaFeO₃ oxygen carriers were also analyzed. The results showed that the band gap was decreased by the doping of low valence. While the doping of low valence element Ca, Sr, and Ba at La site simultaneously resulted to the moving of the valence band toward high energy and made the valence band cross the Fermi energy level. This was resulted from the holes generated by divalent ion substitution. The holes can change the total magnetization from antiferromagnet to weakly ferromagnetism. The calculation results about the formation of oxygen vacancy showed that substitutions of Ca, Sr, and Ba caused a large drop in oxygen vacancy formation energy, indicating that the bulk oxygen transport was improved. Based on the optimized bulk of the undoped and Ca-doped LaFeO₃(010) surface, the CO adsorption was analyzed. The results indicated that the adsorption energy increased by divalent ion substitution, meaning that the adsorption stability decreased. The results can provide a certain theoretical basis for the development of perovskite oxides in chemical looping technologies.Keywords: chemical looping technologies, lanthanum ferrate (LaFeO₃), divalent ion substitution, CO oxidation
Procedia PDF Downloads 1022170 Contrasting Infrastructure Sharing and Resource Substitution Synergies Business Models
Authors: Robin Molinier
Abstract:
Industrial symbiosis (I.S) rely on two modes of cooperation that are infrastructure sharing and resource substitution to obtain economic and environmental benefits. The former consists in the intensification of use of an asset while the latter is based on the use of waste, fatal energy (and utilities) as alternatives to standard inputs. Both modes, in fact, rely on the shift from a business-as-usual functioning towards an alternative production system structure so that in a business point of view the distinction is not clear. In order to investigate the way those cooperation modes can be distinguished, we consider the stakeholders' interplay in the business model structure regarding their resources and requirements. For infrastructure sharing (following economic engineering literature) the cost function of capacity induces economies of scale so that demand pooling reduces global expanses. Grassroot investment sizing decision and the ex-post pricing strongly depends on the design optimization phase for capacity sizing whereas ex-post operational cost sharing minimizing budgets are less dependent upon production rates. Value is then mainly design driven. For resource substitution, synergies value stems from availability and is at risk regarding both supplier and user load profiles and market prices of the standard input. Baseline input purchasing cost reduction is thus more driven by the operational phase of the symbiosis and must be analyzed within the whole sourcing policy (including diversification strategies and expensive back-up replacement). Moreover, while resource substitution involves a chain of intermediate processors to match quality requirements, the infrastructure model relies on a single operator whose competencies allow to produce non-rival goods. Transaction costs appear higher in resource substitution synergies due to the high level of customization which induces asset specificity, and non-homogeneity following transaction costs economics arguments.Keywords: business model, capacity, sourcing, synergies
Procedia PDF Downloads 1742169 The Clash Between Sexual Choices and Socio-Culturo-Religious Morality in Ghana: Public Perceptions on the Impact of Anti-LGBTQIs Activities on Communal Peace
Authors: George Hikah Benson
Abstract:
The promotion of lesbian, gay, bisexual, transgender, queer and Intersex (LGBTQIs) rights within the continent of Africa in general and Ghana, in particular, has for some time now, met the fiercest of resistance; premised mainly on socio-cultural-religious factors. This phenomenon contrasts with notions of countries of the Global North where persons within the context of their fundamental freedoms and rights have the right to sexual choices and preferences. A Private Member’s Bill was introduced to the Ghanaian Parliament in 2021, seeking to criminalize the promotion and advocacy of LGBTQIs related activities. This paper in assessing public views on the matter also seeks to ascertain the security implications regarding the passage of the law at the community level. The study also evaluates LGBTQIs rights vis-a-vis the provisions of Chapter 5 of the 1992 Ghana Constitution and global legal jurisprudence on fundamental human rights. To that end, the study adopted a mixed design approach (quantitative and qualitative) to gather data from 1,550 respondents from all ‘walks of life, across all sixteen regions of Ghana. The main findings are that first, over 85% of Ghanaians abhor the practices of LGBTQIs in keeping with the societal, cultural and religious beliefs of Ghanaians, and will go any length to prevent its survival in the country. Further, the time is not ripe for the acceptance of LGBTQ rights in Ghana as the activities will disrupt family values and poison the existing peace that Ghanaians are currently enjoying. However, it is generally believed that when the bill is passed into law, Ghana’s international image will be dented, and 60% of participants and respondents will be unmoved. Against this hostile, intolerant backdrop regarding LGBTQIs rights in the country and in many other African countries, the study foremost recommends that such a law, when passed, should come with a ‘human face’ that will not just seek to be punitive of LGBTQIs persons but corrective. Additionally, the law should be one that offers them support in line with their rights as Ghanaian and African citizens. Moreover, religious and traditional bodies should endeavor to engage LGBTQIs persons in a friendlier, corrective and loving manner rather than in the current hostile environment that society exposes them to.Keywords: Ghanaian parliament, LGBTQIs rights, perceptions, socio-culture-religious
Procedia PDF Downloads 872168 A Morphological Examination of Urban Renewal Processes: The Sample of Konya City
Authors: Muzaffer Ali Yaygın, Mehmet Topçu
Abstract:
This research aims to investigate morphological changes in urban patterns in urban renewal areas by using geographic information systems and to reveal pattern differences that occur before and after urban renewal processes by applying a morphological analysis. The concept of urban morphology is not involved in urban renewal and urban planning practices in Turkey. This situation destroys the structural characteristic of urban space which appears as a consequence of changes at city, street or plot level. Different approaches and renewal interventions to urban settlements, which are formed as a reflection of cultural issues, may have positive and negative results. A morphological analysis has been applied to an urban renewal area that covers 325 ha. in Konya, in which city urban renewal projects have gained speed with the increasing of economic investments in this study. The study mentions urban renewal and urban morphology relationship, varied academic approach on the urban morphology issue, urban morphology components, changes in lots pattern and numerical differences that occur on road, construction and green space ratios that are before and after the renewal project, and the results of the morphological analysis. It is seen that the built-up area has significant differences when compared to the previous situation. The amount of green areas decreased significantly in quantitative terms; the transportation systems has been changed completely; and the property ownership has been reconstructed without taking the previous situation into account. Findings show that urban renewal projects in Turkey are put into practice with a rent-oriented approach without making an in-depth analysis. The paper discusses the morphological dimension of urban renewal projects in Turkey through a case study from Konya city.Keywords: Konya, pattern, urban morphology, urban renewal
Procedia PDF Downloads 3692167 Community Level Vulnerabilities to Climate Change in Cox’s Bazar-Teknaf Coastal Area of Bangladesh
Authors: Pronob Kumar Mozumder, M. Abdur Rob Mollah
Abstract:
This research was conducted in two coastal locations of Bangladesh from February, 2013 to January, 2014.The objective of this research was to assess the potential vulnerabilities of climate change on local ecosystem and people and to identify and recommend local level adaptation strategies to climate change. Focus group discussions, participatory rural appraisal, interviewing local elderly people were conducted. Perceptions about climate change indicate that local people are experiencing impacts of climate change. According to local people, temperature, cyclone, rain, water-logging, siltation, salinity, erosion, and flash flood are increasing. Vulnerability assessment revealed that local people are variously affected by abnormal climate related disasters. This is jeopardizing their livelihoods, risking their lives, health, and their assets. This prevailing climatic situation in the area is also impacting their environmental conditions, biodiversity and natural resources, and their economic activities. The existing adaptation includes using traditional boat and mobile phone while fishing and making house on high land and lower height. Proposed adaptation for fishing boat are using more than 60 feet length with good timber, putting at least 3 longitudinal bar along upper side, using enough vertical side bars. The homestead measures include use of cross bracing of wall frame, roof tying with extra-post by ropes and plantation of timber tree against wind.Keywords: community level vulnerabilities, climate change, Cox’s Bazar-Teknaf Coastal Area, Bangladesh
Procedia PDF Downloads 5372166 Assessing Walkability in New Cities around Cairo
Authors: Lobna Ahmed Galal
Abstract:
Modal integration has given minimal consideration in cities of developing countries, as well as the declining dominance of public transport, and predominance of informal transport, the modal share of informal taxis in greater Cairo has increased from 6% in 1987 to 37% in 2001 and this has since risen even higher, informal and non-motorized modes of transport acting as a gap filler by feeding other modes of transport, not by design or choice, but often by lack of accessible and affordable public transport. Yet non-motorized transport is peripheral, with minimal priority in urban planning and investments, lacking of strong polices to support non-motorized transport, for authorities development is associated with technology and motorized transport, and promotion of non-motorized transport may be considered corresponding to development, as well as social stigma against non-motorized transport, as it is seen a travel mode for the poor. Cairo as a city of a developing country, has poor quality infrastructure for non-motorized transport, suffering from absence of dedicated corridors, and when existing they are often encroached for commercial purposes, widening traffic lanes at the expense of sidewalks, absence of footpaths, or being overcrowded, poor lighting, making walking unsafe and yet, lack of financial supply to such facilities as it is often considered beyond city capabilities. This paper will deal with the objective measuring of the built environment relating to walking, in some neighborhoods of new cities around Cairo, In addition to comparing the results of the objective measures of the built environment with the level of self-reported survey. The first paper's objective is to show how the index ‘walkability of community neighborhoods’ works in the contexts in neighborhoods of new cities around Cairo. The procedure of objective measuring is of a high potential to be carried out by using GIS.Keywords: assessing, built environment, Cairo, walkability
Procedia PDF Downloads 3832165 Influence of the Induction Program on Novice Teacher Retention In One Specialized School in Nur-Sultan
Authors: Almagul Nurgaliyeva
Abstract:
The phenomenon of novice teacher attrition is an urgent issue. The effective mechanisms to increase the retention rate of novice teachers relate to the nature and level of support provided at an employing site. This study considered novice teacher retention as a motivation-based process, which is based on a variety of support activities employed to satisfy novice teachers’ needs at an early career stage. The purpose of the study was to examine novice teachers’ perceptions of the effectiveness of the induction program and other support structure(s) at a secondary school in Nur-Sultan. The study was guided by Abraham Maslow’s (1943) theory of motivation. Maslow’s hierarchy of needs was used as a theoretical framework to identify the novice teachers’ primary needs and the extent to which the induction programs and other support mechanisms provided by the school administrators fulfill those needs. One school supervisor and eight novice teachers (four current and four former novice teachers) with a maximum of four years of teaching experience took part in the study. To investigate the perspectives and experiences of the participants, an online semi-structured interview was utilized. The responses were collected and analyzed. The study revealed four major challenges: educational, personal-psychological, sociological, and structural which are seen as the main constraints during the adaptation period. Four induction activities, as emerged from the data, are being carried out by the school to address novice teachers’ challenges: socialization activities, mentoring programs, professional development, and administrative support. These activities meet novice teachers’ needs and confront the challenges they face. Sufficient and adequate support structures provided to novice teachers during their first years of working experience is essential, as they may influence their decision to remain in the teaching profession, thereby reducing the attrition rate. The study provides recommendations for policymakers and school administrators about the structure and the content of induction program activities.Keywords: beginning teacher induction, induction programme, orientation programmes, adaptation challenges, novice teacher retention
Procedia PDF Downloads 872164 Application of Building Information Modelling In Analysing IGBC® Ratings (Sustainability Analyses)
Authors: Lokesh Harshe
Abstract:
The building construction sector is using 36% of global energy consumption with 39% of CO₂ emission. Professionals in the Built Environment Sector have long been aware of the industry’s contribution towards CO₂ emissions and are now moving towards more sustainable practices. As a result of this, many organizations have introduced rating systems to address the issue of global warming in the construction sector by ranking construction projects based on sustainability parameters. The pre-construction phase of any building project is the most essential time to make decisions for addressing the sustainability aspects. Traditionally, it is very difficult to collect data from different stakeholders and bring it together to form a decision based on factual data to perform sustainability analyses in the pre-construction phase. Building Information Modelling (BIM) is the solution where one single model is the result of the collaborative approach of BIM processes where all the information is shared, extracted, communicated, and stored on a single platform that everyone can access and make decisions based on real-time data. The focus of this research is on the Indian Green Rating System IGBC® with the objective of understanding IGBC® requirements and developing a framework to create the relationship between the rating processes and BIM. A Hypothetical (Architectural) model of a hostel building is developed using AutoCAD 2019 & Revit Arch. 2019, where the framework is applied to generate results on sustainability analysis using Green Building Studio (GBS) and Revit Add-ins. The results of any sustainability analysis are generated within a fraction of a minute, which is very quick in comparison with traditional sustainability analysis. This may save a considerable amount of time as well as cost. The future scope is to integrate Architectural, Structural, and MEP Models to perform accurate sustainability analyses with inputs from industry professionals working on real-life Green BIM projects.Keywords: sustainability analyses, BIM, green rating systems, IGBC®, LEED
Procedia PDF Downloads 542163 The Application of Karonda Friuts (Carissa carandas Linn.) for Ice Cream-Making
Authors: A. Pornpitakdumrong
Abstract:
The aim of this research study was to develop recipe of Karanda ice cream as healthy promoting ice cream by high protein, low fat and naturally raw material, which found in local area. The results were found that appropriate condition for Karanda ice cream including incubation period, temperature and frozen time, which were 8-12 hours, -20 to -25 °C and 2-4 hours, respectively. Small fruit variety Karanda should selected only ripe fruits for Karanda ice cream made. Because of unripe fruits were contained resin and need to be air dried for reducing level of resin. Therefore, large fruit variety Karanda can be use both ripe and unripe fruits for Karanda ice cream made by without any astringent and bitter taste. However, small fruit variety Karanda was proper to made ice cream for trade, because occurring of industry to select the ripe fruits and commercially frozen, which be providing for the whole year compared with large variety fruits were rarely, low harvesting amount and short shelf life. Karanda ice cream produced from flesh part was attractive but was not accepted by consumers. It may due to resin contained with Karanda pulp, which led to be rough texture of ice cream. We were choose only Karanda juice, which was more appropriated and used Karanda juice with water by 1:1 ratio, because undiluted juice was sour taste. Most acceptance recipe of karanda ice cream product was sixth recipe by 91% of consumers, which was contained soy protein to made ice cream was delicate and swell, milk powder (little amount) to made ice cream was greasy, corn powder as stabilizer and undiluted coconut milk (little amount) to improve ice cream odor and similar to apricot odor.Keywords: karonda fruits, Carissa carandas Linn, ice cream, healthy ice cream
Procedia PDF Downloads 4102162 Development of a Miniature and Low-Cost IoT-Based Remote Health Monitoring Device
Authors: Sreejith Jayachandran, Mojtaba Ghods, Morteza Mohammadzaheri
Abstract:
The modern busy world is running behind new embedded technologies based on computers and software; meanwhile, some people forget to do their health condition and regular medical check-ups. Some of them postpone medical check-ups due to a lack of time and convenience, while others skip these regular evaluations and medical examinations due to huge medical bills and hospital expenses. Engineers and medical experts have come together to give birth to a new device in the telemonitoring system capable of monitoring, checking, and evaluating the health status of the human body remotely through the internet for the needs of all kinds of people. The remote health monitoring device is a microcontroller-based embedded unit. Various types of sensors in this device are connected to the human body, and with the help of an Arduino UNO board, the required analogue data is collected from the sensors. The microcontroller on the Arduino board processes the analogue data collected in this way into digital data and transfers that information to the cloud, and stores it there, and the processed digital data is instantly displayed through the LCD attached to the machine. By accessing the cloud storage with a username and password, the concerned person’s health care teams/doctors and other health staff can collect this data for the assessment and follow-up of that patient. Besides that, the family members/guardians can use and evaluate this data for awareness of the patient's current health status. Moreover, the system is connected to a Global Positioning System (GPS) module. In emergencies, the concerned team can position the patient or the person with this device. The setup continuously evaluates and transfers the data to the cloud, and also the user can prefix a normal value range for the evaluation. For example, the blood pressure normal value is universally prefixed between 80/120 mmHg. Similarly, the RHMS is also allowed to fix the range of values referred to as normal coefficients. This IoT-based miniature system (11×10×10) cm³ with a low weight of 500 gr only consumes 10 mW. This smart monitoring system is manufactured with 100 GBP, which can be used not only for health systems, it can be used for numerous other uses including aerospace and transportation sections.Keywords: embedded technology, telemonitoring system, microcontroller, Arduino UNO, cloud storage, global positioning system, remote health monitoring system, alert system
Procedia PDF Downloads 902161 Performance Augmentation of a Combined Cycle Power Plant with Waste Heat Recovery and Solar Energy
Authors: Mohammed A. Elhaj, Jamal S. Yassin
Abstract:
In the present time, energy crises are considered a severe problem across the world. For the protection of global environment and maintain ecological balance, energy saving is considered one of the most vital issues from the view point of fuel consumption. As the industrial sectors everywhere continue efforts to improve their energy efficiency, recovering waste heat losses provides an attractive opportunity for an emission free and less costly energy resource. In the other hand the using of solar energy has become more insistent particularly after the high gross of prices and running off the conventional energy sources. Therefore, it is essential that we should endeavor for waste heat recovery as well as solar energy by making significant and concrete efforts. For these reasons this investigation is carried out to study and analyze the performance of a power plant working by a combined cycle in which Heat Recovery System Generator (HRSG) gets its energy from the waste heat of a gas turbine unit. Evaluation of the performance of the plant is based on different thermal efficiencies of the main components in addition to the second law analysis considering the exergy destructions for the whole components. The contribution factors including the solar as well as the wasted energy are considered in the calculations. The final results have shown that there is significant exergy destruction in solar concentrator and the combustion chamber of the gas turbine unit. Other components such as compressor, gas turbine, steam turbine and heat exchangers having insignificant exergy destruction. Also, solar energy can contribute by about 27% of the input energy to the plant while the energy lost with exhaust gases can contribute by about 64% at maximum cases.Keywords: solar energy, environment, efficiency, waste heat, steam generator, performance, exergy destruction
Procedia PDF Downloads 2982160 Low Temperature Biological Treatment of Chemical Oxygen Demand for Agricultural Water Reuse Application Using Robust Biocatalysts
Authors: Vedansh Gupta, Allyson Lutz, Ameen Razavi, Fatemeh Shirazi
Abstract:
The agriculture industry is especially vulnerable to forecasted water shortages. In the fresh and fresh-cut produce sector, conventional flume-based washing with recirculation exhibits high water demand. This leads to a large water footprint and possible cross-contamination of pathogens. These can be alleviated through advanced water reuse processes, such as membrane technologies including reverse osmosis (RO). Water reuse technologies effectively remove dissolved constituents but can easily foul without pre-treatment. Biological treatment is effective for the removal of organic compounds responsible for fouling, but not at the low temperatures encountered at most produce processing facilities. This study showed that the Microvi MicroNiche Engineering (MNE) technology effectively removes organic compounds (> 80%) at low temperatures (6-8 °C) from wash water. The MNE technology uses synthetic microorganism-material composites with negligible solids production, making it advantageously situated as an effective bio-pretreatment for RO. A preliminary technoeconomic analysis showed 60-80% savings in operation and maintenance costs (OPEX) when using the Microvi MNE technology for organics removal. This study and the accompanying economic analysis indicated that the proposed technology process will substantially reduce the cost barrier for adopting water reuse practices, thereby contributing to increased food safety and furthering sustainable water reuse processes across the agricultural industry.Keywords: biological pre-treatment, innovative technology, vegetable processing, water reuse, agriculture, reverse osmosis, MNE biocatalysts
Procedia PDF Downloads 1292159 Gender Equity in Everyday Lives: A Case Study from New Delhi, India
Authors: Shrutika Lakshmi
Abstract:
Gender inequality has been quite evident particularly in the third world economies in different domains like health, education, marriages and personal freedom. Women’s exercise to personal freedom is driven by their financial standing in third world social milieu. However, even after decades of attempt to achieve a socio-economic standing equal to men, their attempts have failed in registering success.This research has been conducted in the national capital of India New Delhi aiming to reflect upon the gendered relations in society on the category of employed women. This particular category of women have been chosen for the study in order to study the gender relations, subordination of such women in household despite having an economic standing of their own, etc. The methodology used for this study is semi-structured interview along with qualitative analysis. Moreover, with the help of direct interaction with these women, we get insight into the kind of gendered relations prevailing inside the household structure which have their roots in age old customs and stereotype of the social milieu. Most importantly, the highlight of the study remains on the point where the hierarchy remains in the subconscious of these women and they never forget their social standing. It has been interesting to note that how even after contributing to the family income successively, their position remains subjugated in front of their male counterparts and thus, they are not ‘free’ in the real sense of the term. Even after attaining an economically stable position, these women did not enjoy the same comfort and freedom of choice as their male counterparts do, this could be gauged from the fact that when asked about ‘time for one’s own self’ they had no sense of it. This is astonishing in today’s world where every individual works and strives for a better livelihood and quality existence. Such findings reflect upon the reality of our society where women are still subjugated and duty bound towards the household even after having the same economic stand as their male counterparts. The burden of household chores and responsibilities fall solely on the shoulders of a women despite being an employed women even in the present times. Cooperation comes primarily from female members of the household and not from males. And thus, we as a society are far away from gender equity. We still suffer from prejudices and stereotypes which prevent us from giving same respect to women which we keep reserved for the man. Given this scenario, it seems, gender equity is a distant goal which we will have to keep striving for even harder even after decades of feminist struggles all over the world.Keywords: employed women, subjugation in household, gender hierarchy, financial independence,
Procedia PDF Downloads 1562158 Sociology of Muslim Endowments (Waqf) in Indian Kashmir: A Thesis Report
Authors: Adfer Rashid Shah
Abstract:
This study brings an introduction to the concept of waqf and explores the institution of waqf in the valley of Kashmir. Waqfs (pl. Auqaf) are Islamic endowments which can be movable or immovable property by Muslims for the welfare of the poor and the upkeep of the mosques, shrines, imambaras, madrassas, orphanages, etc,. The study was undertaken to venture into the sociology of these endowments and see the dynamics and role of waqf institution in the welfare of masses especially the deserving populace of the state of Jamu and Kashmir. The Jammu and Kashmir Muslim Waqf Board (JKMWB) is a significant religio-social organization for it possesses the largest assets after the State government and has an immense potential and ownership in terms of huge properties besides having rich and perpetual cash and kind donations, gold, silver and other commodities from the believers. It is certainly the perpetual wealth of faith. Therefore this study besides exploring the waqf institution, sociologically probed into the social, religious and philanthropic interventions of the Wakf Board besides studying the waqf of education (both religious and general). Also, a passing reference on personalized Auqaf, local waqf committees particularly shia Auqaf was also made. As far methodology employed, the study was purely a qualitative study using various sociological perspectives like functionalism, grounded theory besides a range other concepts to see the total role of waqf that it has been playing for the people’s welfare in the valley of Kashmir since its establishment in 1940’s. The overall discussion revealed the social dynamics of waqf institution in Kashmir valley is increasing its social interventions and making difference in the lives of many deserving Muslims within its capacities.Keywords: waqf, wakf board, religious waqf, philanthropy and education waqf, religious waqf, Kashmir
Procedia PDF Downloads 3182157 Emigration Improves Life Standard of Families Left Behind: An Evidence from Rural Area of Gujrat-Pakistan
Authors: Shoaib Rasool
Abstract:
Migration trends in rural areas of Gujrat are increasing day by day among illiterate people as they consider it as a source of attraction and charm of destination. It affects the life standard both positive and negative way to their families left behind in the context of poverty, socio-economic status and life standards. It also promotes material items and as well as social indicators of living, housing conditions, schooling of their children’s, health seeking behavior and to some extent their family environment. The nature of the present study is to analyze socio-economic conditions regarding life standard of emigrant families left behind in rural areas of Gujrat district, Pakistan. A survey design was used on 150 families selected from rural areas of Gujrat districts through purposive sampling technique. A well-structured questionnaire was administered by the researcher to explore the nature of the study and for further data collection process. The measurement tool was pretested on 20 families to check the workability and reliability before the actual data collection. Statistical tests were applied to draw results and conclusion. The preliminary findings of the study show that emigration has left deep social-economic impacts on life standards of rural families left behind in Gujrat. They improved their life status and living standard through remittances. Emigration is one of the major sources of development of economy of household and it also alleviate poverty at house household level as well as community and country level. The rationale behind migration varies individually and geographically. There are popular considered attractions in Pakistan includes securing high status, improvement in health condition, coping other, getting married then to acquire nationality, using the unfair means, opting educational visas etc. Emigrants are not only sending remittances but also returning with newly acquired skills and valuable knowledge to their country of origin because emigrants learn new methods of living and working. There are also women migrants who experience social downward mobility by engaging in jobs that are beneath their educational qualifications.Keywords: emigration, life standard, families, left behind, rural area, Gujrat
Procedia PDF Downloads 4432156 The Development of a Nanofiber Membrane for Outdoor and Activity Related Purposes
Authors: Roman Knizek, Denisa Knizkova
Abstract:
This paper describes the development of a nanofiber membrane for sport and outdoor use at the Technical University of Liberec (TUL) and the following cooperation with a private Czech company which launched this product onto the market. For making this membrane, Polyurethan was electrospun on the Nanospider spinning machine, and a wire string electrode was used. The created nanofiber membrane with a nanofiber diameter of 150 nm was subsequently hydrophobisied using a low vacuum plasma and Fluorocarbon monomer C6 type. After this hydrophobic treatment, the nanofiber membrane contact angle was higher than 125o, and its oleophobicity was 6. The last step was a lamination of this nanofiber membrane with a woven or knitted fabric to create a 3-layer laminate. Gravure printing technology and polyurethane hot-melt adhesive were used. The gravure roller has a mesh of 17. The resulting 3-layer laminate has a water vapor permeability Ret of 1.6 [Pa.m2.W-1] (– measured in compliance with ISO 11092), it is 100% windproof (– measured in compliance with ISO 9237), and the water column is above 10 000 mm (– measured in compliance with ISO 20811). This nanofiber membrane which was developed in the laboratories of the Technical University of Liberec was then produced industrially by a private company. A low vacuum plasma line and a lamination line were needed for industrial production, and the process had to be fine-tuned to achieve the same parameters as those achieved in the TUL laboratories. The result of this work is a newly developed nanofiber membrane which offers much better properties, especially water vapor permeability, than other competitive membranes. It is an example of product development and the consequent fine-tuning for industrial production; it is also an example of the cooperation between a Czech state university and a private company.Keywords: nanofiber membrane, start-up, state university, private company, product
Procedia PDF Downloads 1422155 Pragmatism in Adaptive Reuse of Obsolete Industrial Land in China
Authors: Yong Li
Abstract:
Major cities in China has experienced a shift from production based on manufacturing industry to tertiary industry. How to make a better use of existing obsolete industrial land within urban cores has become a difficult problem for many policymakers. City governments regard old manufacturing industrial land as an important source of land to facilitate the development of the cities. Despite the announcement of policies in promoting that, a large portion of industrial land is still not properly redeveloped and most of them became obsolete. The study uses the project of Xinyi International Club as a case to examine the process of adaptive reuse of obsolete industrial space in Guangzhou, China. It attempts to elucidate the underlying mechanisms by identifying the key forces from both the government and the private sectors in influencing the process. The study found that market forces in transforming industrial space are exerting a strong impact on the existing land use planning system in Chinese cities. Pragmatic relaxation of the formal land use the regulatory framework and government supportive land-use intervention have also been crucial towards achieving successful implementation of the restructuring project and making it a showcase. This study questions whether these extraordinary measures, in particular, the use of temporary land use permit, are sustainable in facilitating the transformation of derelict industrial land, and in informing future industrial land-use restructuring policies. It concludes that, while the land use regulatory system in China is becoming increasingly dynamic and flexible, it remains ill-equipped in responding positively to the market, which is characterized by an increasing bargaining power of the private sector. A comprehensive appraisal of the overall impacts of these adaptive re-uses on society is wanting.Keywords: China, land alteration, obsolete industrial properties, urban planning
Procedia PDF Downloads 1462154 A Pilot Study on Integration of Simulation in the Nursing Educational Program: Hybrid Simulation
Authors: Vesile Unver, Tulay Basak, Hatice Ayhan, Ilknur Cinar, Emine Iyigun, Nuran Tosun
Abstract:
The aim of this study is to analyze the effects of the hybrid simulation. In this simulation, types standardized patients and task trainers are employed simultaneously. For instance, in order to teach the IV activities standardized patients and IV arm models are used. The study was designed as a quasi-experimental research. Before the implementation an ethical permission was taken from the local ethical commission and administrative permission was granted from the nursing school. The universe of the study included second-grade nursing students (n=77). The participants were selected through simple random sample technique and total of 39 nursing students were included. The views of the participants were collected through a feedback form with 12 items. The form was developed by the authors and “Patient intervention self-confidence/competence scale”. Participants reported advantages of the hybrid simulation practice. Such advantages include the following: developing connections between the simulated scenario and real life situations in clinical conditions; recognition of the need for learning more about clinical practice. They all stated that the implementation was very useful for them. They also added three major gains; improvement of critical thinking skills (94.7%) and the skill of making decisions (97.3%); and feeling as if a nurse (92.1%). In regard to the mean scores of the participants in the patient intervention self-confidence/competence scale, it was found that the total mean score for the scale was 75.23±7.76. The findings obtained in the study suggest that the hybrid simulation has positive effects on the integration of theoretical and practical activities before clinical activities for the nursing students.Keywords: hybrid simulation, clinical practice, nursing education, nursing students
Procedia PDF Downloads 2932153 Determination of the Thermophysical Characteristics of the Composite Material Clay Cement Paper
Authors: A. Ouargui, N. Belouaggadia, M. Ezzine
Abstract:
In Morocco, the building sector is largely responsible for the evolution of energy consumption. The control of energy in this sector remains a major issue despite the rise of renewable energies. The design of an environmentally friendly building requires mastery and knowledge of energy and bioclimatic aspects. This implies taking into consideration of all the elements making up the building and the way in which energy exchanges take place between these elements. In this context, thermal insulation seems to be an ideal starting point for reducing energy consumption and greenhouse gas emissions. In this context, thermal insulation seems to be an ideal starting point for reducing energy consumption and greenhouse gas emissions. The aim of this work is to provide some solutions to reduce energy consumption while maintaining thermal comfort in the building. The objective of our work is to present an experimental study on the characterization of local materials used in the thermal insulation of buildings. These are paper recycling stabilized with cement and clay. The thermal conductivity of these materials, which were constituted based on sand, clay, cement; water, as well as treated paper, was determined by the guarded-hot-plate method. It involves the design of two materials that will subsequently be subjected to thermal and mechanical tests to determine their thermophysical properties. The results show that the thermal conductivity decreases as well in the case of the paper-cement mixture as that of the paper-clay and seems to stabilize around 40%. Measurements of mechanical properties such as flexural strength have shown that the enrichment of the studied material with paper makes it possible to reduce the flexural strength by 20% while optimizing the conductivity.Keywords: building, composite material, insulation, thermal conductivity, paper residue
Procedia PDF Downloads 1272152 Noise Pollution: An Emerging Threat to Urban Health
Authors: M. Sirajul Islam Molla
Abstract:
Noise pollution has been a continuous and an increasing threat to human health in urban population all over the world. The situation in Bangladesh particularly in major cities has been dangerously aggravating. Despite the government of Bangladesh have laws in its hand to curb the noise pollution the authority’s reluctance in enforcing it, is making the situation worse. We do not see any difference in some other major cities of the South Asian Regional Countries like Delhi and Kathmandu, both of the cities are facing the same situation like Dhaka. With the expansion of technology-based township all over the world, the noise pollution has been an emerging threat to urban health. The information for this review has been derived from websites of GOs, NGOs, peer-reviewed papers, seminars and symposia. The worse situation of noise pollution results in people’s irritation and protest, but in many cases, the protesters are facing the wrath of the polluters. Two such consequences in Bangladesh have resulted in killing the protesters by the polluters – one happened in Dhaka city and the other in a rural town. The law-enforcing agencies proactively do not attempt to impose the law. Noise pollution has been increasing so rapidly that it has become a burden on human health in urban populations. Prolonged exposure to higher noise causes mental stress, sleeplessness, high blood pressure, cardiac failure, respiratory disorder, miscarriage and breaks attention of students to their studies and also irritates their behavior. The noise pollution-caused mortality has also been increasing all over the world. Recommendations from the international conferences such as ICUH should be forwarded to the United Nations. The UN then should pass it on to the concerned countries. The UN should also keenly monitor if the countries have appropriate plan to curb noise pollution to meet the sustainable development goals.Keywords: decibel, environment, noise, pollution
Procedia PDF Downloads 2442151 Effect of Plant Growth Promoting Rhizobacteria on the Germination and Early Growth of Onion (Allium cepa)
Authors: Dragana R. Stamenov, Simonida S. Djuric, Timea Hajnal Jafari
Abstract:
Plant growth promoting rhizobacteria (PGPR) are a heterogeneous group of bacteria that can be found in the rhizosphere, at root surfaces and in association with roots, enhancing the growth of the plant either directly and/or indirectly. Increased crop productivity associated with the presence of PGPR has been observed in a broad range of plant species, such as raspberry, chickpeas, legumes, cucumber, eggplant, pea, pepper, radish, tobacco, tomato, lettuce, carrot, corn, cotton, millet, bean, cocoa, etc. However, until now there has not been much research about influences of the PGPR on the growth and yield of onion. Onion (Allium cepa L.), of the Liliaceae family, is a species of great economic importance, widely cultivated all over the world. The aim of this research was to examine the influence of plant growth promoting bacteria Pseudomonas sp. Dragana, Pseudomonas sp. Kiš, Bacillus subtillis and Azotobacter sp. on the seed germination and early growth of onion (Allium cepa). PGPR Azotobacter sp., Bacillus subtilis, Pseudomonas sp. Dragana, Pseudomonas sp. Kiš, from the collection of the Faculty of Agriculture, Novi Sad, Serbia, were used as inoculants. The number of cells in 1 ml of the inoculum was 10⁸ CFU/ml. The control variant was not inoculated. The effect of PGPR on seed germination and hypocotyls length of Allium cepa was evaluated in controlled conditions, on filter paper in the dark at 22°C, while effect on the plant length and mass in semicontrol conditions, in 10 l volume vegetative pots. Seed treated with fungicide and untreated seed were used. After seven days the percentage of germination was determined. After seven and fourteen days hypocotil length was measured. Fourteen days after germination, length and mass of plants were measured. Application of Pseudomonas sp. Dragana and Kiš and Bacillus subtillis had a negative effect on onion seed germination, while the use of Azotobacter sp. gave positive results. On average, application of all investigated inoculants had a positive effect on the measured parameters of plant growth. Azotobacter sp. had the greatest effect on the hypocotyls length, length and mass of the plant. In average, better results were achieved with untreated seeds in compare with treated. Results of this study have shown that PGPR can be used in the production of onion.Keywords: germination, length, mass, microorganisms, onion
Procedia PDF Downloads 2372150 Youth and Radicalization: Main Causes Who Lead Young People to Radicalize in a Context with Background of Radicalization
Authors: Zineb Emrane
Abstract:
This abstract addresses the issue of radicalization of young people in a context with background of radicalization, in North of Morocco, 5 terrorist of Madrid's Attacts on 11th March, were coming from this context. It were developed a study pilot that describing young people perception about the main causes that lead and motivate for radicalization. Whenever we talk about this topic, we obtain information from studies and investigations by specialists in field, but we don’t give voice to the protagonists who in many cases are victims, specifically, young people at social risk because of social factors. Extremist radicalization is an expanding phenomenon, that affect young people, in north of Morocco. They live in a context with radical background and at risk of social exclusion, their social, economic and familiar needs make them vulnerable. The extremist groups take advantage of this vulnerability to involve them in a process of radicalization, offering them an alternative environment where they can found all they are looking for. This study pilot approaches the main causes that lead and motivates young people to become radicals, analyzing their context with emphasis on influencing factors, and bearing in mind the analysis of young people about how the radical background affect them and their opinion this phenomenon. The pilot study was carried out through the following actions: - Group dynamics with young people to analyze the process of violent radicalization of young people. -A participatory workshop with members of organizations that work directly with young people at risk of radicalization. -Interviews with institutional managers -Participant observation. The implementation of actions has led to the conclusion that young people define violent radicalization as a sequential process, depending on the stage, it can be deconstructed. Young people recognize that they stop feeling belonging to their family, school and neighborhood when they see behavior contrary to what they consider good and evil. The emotional rupture and the search for references outside their circle, push them to sympathize with groups that have an extremist ideology and that offer them what they need. The radicalization is a process with different stages, the main causes and the factors which lead young people to use extremist violence are related their low level of belonging feeling to their context, and lack of critical thinking about important issues. The young people are in a vulnerable stage, searching their identity, a space in which they can be accepted, and when they don't find it they are easily manipulated and susceptible to being attracted by extremist groups.Keywords: exclusion, radicalization, vulnerability, youth
Procedia PDF Downloads 1632149 Accounting for Rice Productivity Heterogeneity in Ghana: The Two-Step Stochastic Metafrontier Approach
Authors: Franklin Nantui Mabe, Samuel A. Donkoh, Seidu Al-Hassan
Abstract:
Rice yields among agro-ecological zones are heterogeneous. Farmers, researchers and policy makers are making frantic efforts to bridge rice yield gaps between agro-ecological zones through the promotion of improved agricultural technologies (IATs). Farmers are also modifying these IATs and blending them with indigenous farming practices (IFPs) to form farmer innovation systems (FISs). Also, different metafrontier models have been used in estimating productivity performances and their drivers. This study used the two-step stochastic metafrontier model to estimate the productivity performances of rice farmers and their determining factors in GSZ, FSTZ and CSZ. The study used both primary and secondary data. Farmers in CSZ are the most technically efficient. Technical inefficiencies of farmers are negatively influenced by age, sex, household size, education years, extension visits, contract farming, access to improved seeds, access to irrigation, high rainfall amount, less lodging of rice, and well-coordinated and synergized adoption of technologies. Albeit farmers in CSZ are doing well in terms of rice yield, they still have the highest potential of increasing rice yield since they had the lowest TGR. It is recommended that government through the ministry of food and agriculture, development partners and individual private companies promote the adoption of IATs as well as educate farmers on how to coordinate and synergize the adoption of the whole package. Contract farming concept and agricultural extension intensification should be vigorously pursued to the latter.Keywords: efficiency, farmer innovation systems, improved agricultural technologies, two-step stochastic metafrontier approach
Procedia PDF Downloads 2672148 Rhizoremediation of Contaminated Soils in Sub-Saharan Africa: Experimental Insights of Microbe Growth and Effects of Paspalum Spp. for Degrading Hydrocarbons in Soils
Authors: David Adade-Boateng, Benard Fei Baffoe, Colin A. Booth, Michael A. Fullen
Abstract:
Remediation of diesel fuel, oil and grease in contaminated soils obtained from a mine site in Ghana are explored using rhizoremediation technology with different levels of nutrient amendments (i.e. N (nitrogen) in Compost (0.2, 0.5 and 0.8%), Urea (0.2, 0.5 and 0.8%) and Topsoil (0.2, 0.5 and 0.8%)) for a native species. A Ghanaian native grass species, Paspalum spp. from the Poaceae family, indicative across Sub-Saharan Africa, was selected following the development of essential and desirable growth criteria. Vegetative parts of the species were subjected to ten treatments in a Randomized Complete Block Design (RCBD) in three replicates. The plant-associated microbial community was examined in Paspalum spp. An assessment of the influence of Paspalum spp on the abundance and activity of micro-organisms in the rhizosphere revealed a build-up of microbial communities over a three month period. This was assessed using the MPN method, which showed rhizospheric samples from the treatments were significantly different (P <0.05). Multiple comparisons showed how microbial populations built-up in the rhizosphere for the different treatments. Treatments G (0.2% compost), H (0.5% compost) and I (0.8% compost) performed significantly better done other treatments, while treatments D (0.2% topsoil) and F (0.8% topsoil) were insignificant. Furthermore, treatment A (0.2% urea), B (0.5% urea), C (0.8% urea) and E (0.5% topsoil) also performed the same. Residual diesel and oil concentrations (as total petroleum hydrocarbons, TPH and oil and grease) were measured using infra-red spectroscopy and gravimetric methods, respectively. The presence of single species successfully enhanced the removal of hydrocarbons from soil. Paspalum spp. subjected to compost levels (0.5% and 0.8%) and topsoil levels (0.5% and 0.8%) showed significantly lower residual hydrocarbon concentrations compared to those treated with Urea. A strong relationship (p<0.001) between the abundance of hydrocarbon degrading micro-organisms in the rhizosphere and hydrocarbon biodegradation was demonstrated for rhizospheric samples with treatment G (0.2% compost), H (0.5% compost) and I (0.8% compost) (P <0.001). The same level of amendment with 0.8% compost (N-level) can improve the application effectiveness. These findings have wide-reaching implications for the environmental management of soils contaminated by hydrocarbons in Sub-Saharan Africa. However, it is necessary to further investigate the in situ rhizoremediation potential of Paspalum spp. at the field scale.Keywords: rhizoremediation, microbial population, rhizospheric sample, treatments
Procedia PDF Downloads 3252147 Biochar Affects Compressive Strength of Portland Cement Composites: A Meta-Analysis
Authors: Zhihao Zhao, Ali El-Nagger, Johnson Kau, Chris Olson, Douglas Tomlinson, Scott X. Chang
Abstract:
One strategy to reduce CO₂ emissions from cement production is to reduce the amount of Portland cement produced by replacing it with supplementary cementitious materials (SCMs). Biochar is a potential SCM that is an eco-friendly and stable porous pyrolytic material. However, the effects of biochar addition on the performances of Portland cement composites are not fully understood. This meta-analysis investigated the impact of biochar addition on the 7- and 28-day compressive strength of Portland cement composites based on 606 paired observations. Biochar feedstock type, pyrolysis conditions, pre-treatments and modifications, biochar dosage, and curing type all influenced the compressive strength of Portland cement composites. Biochars obtained from plant-based feedstocks (except rice and hardwood) improved the 28-day compressive strength of Portland cement composites by 3-13%. Biochars produced at pyrolysis temperatures higher than 450 °C, with a heating rate of around 10 °C/min, increased the 28-day compressive strength more effectively. Furthermore, the addition of biochars with small particle sizes increased the compressive strength of Portland cement composites by 2-7% compared to those without biochar addition. Biochar dosage of < 2.5% of the binder weight enhanced both compressive strengths and common curing methods maintained the effect of biochar addition. However, when mixing the cement, adding fine and coarse aggregates such as sand and gravel affects the concrete and mortar's compressive strength, diminishing the effect of biochar addition and making the biochar effect nonsignificant. We conclude that appropriate biochar addition could maintain or enhance the mechanical performance of Portland cement composites, and future research should explore the mechanisms of biochar effects on the performance of cement composites.Keywords: biochar, Portland cement, constructure, compressive strength, meta-analysis
Procedia PDF Downloads 672146 Vibration Absorption Strategy for Multi-Frequency Excitation
Authors: Der Chyan Lin
Abstract:
Since the early introduction by Ormondroyd and Den Hartog, vibration absorber (VA) has become one of the most commonly used vibration mitigation strategies. The strategy is most effective for a primary plant subjected to a single frequency excitation. For continuous systems, notable advances in vibration absorption in the multi-frequency system were made. However, the efficacy of the VA strategy for systems under multi-frequency excitation is not well understood. For example, for an N degrees-of-freedom (DOF) primary-absorber system, there are N 'peak' frequencies of large amplitude vibration per every new excitation frequency. In general, the usable range for vibration absorption can be greatly reduced as a result. Frequency modulated harmonic excitation is a commonly seen multi-frequency excitation example: f(t) = cos(ϖ(t)t) where ϖ(t)=ω(1+α sin(δt)). It is known that f(t) has a series expansion given by the Bessel function of the first kind, which implies an infinity of forcing frequencies in the frequency modulated harmonic excitation. For an SDOF system of natural frequency ωₙ subjected to f(t), it can be shown that amplitude peaks emerge at ω₍ₚ,ₖ₎=(ωₙ ± 2kδ)/(α ∓ 1),k∈Z; i.e., there is an infinity of resonant frequencies ω₍ₚ,ₖ₎, k∈Z, making the use of VA strategy ineffective. In this work, we propose an absorber frequency placement strategy for SDOF vibration systems subjected to frequency-modulated excitation. An SDOF linear mass-spring system coupled to lateral absorber systems is used to demonstrate the ideas. Although the mechanical components are linear, the governing equations for the coupled system are nonlinear. We show using N identical absorbers, for N ≫ 1, that (a) there is a cluster of N+1 natural frequencies around every natural absorber frequency, and (b) the absorber frequencies can be moved away from the plant's resonance frequency (ω₀) as N increases. Moreover, we also show the bandwidth of the VA performance increases with N. The derivations of the clustering and bandwidth widening effect will be given, and the superiority of the proposed strategy will be demonstrated via numerical experiments.Keywords: Bessel function, bandwidth, frequency modulated excitation, vibration absorber
Procedia PDF Downloads 157