Search results for: 3d finite element model

Authors: Khadidja Rahmani, Nahla Bouaziz

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The climate change and the economic crisis, which are currently running, are the origin of the emergence of many issues and problems, which are related to the domain of energy and environment in à direct or indirect manner. Since the urban space is the core element and the key to solve the current problem, particular attention is given to it in this study. For this reason, we rented to the later a very particular attention; this is for the opportunities that it provides and that can be invested to attenuate a little this situation, which is disastrous and worried, especially in the face of the requirements of sustainable development. Indeed, the purpose of this work is to develop a method, which will allow us to guide designers towards projects with a certain degree of thermo-aeraulic comfort while requiring a minimum energy consumption. In this context, the architects, the urban planners and the engineers (energeticians) have to collaborate jointly to establish a method based on indicators for the improvement of the urban environmental quality (aeraulic-thermo comfort), correlated with a reduction in the energy demand of the entities that make up this environment, in areas with a sub-humid climate. In order to test the feasibility and to validate the method developed in this work, we carried out a series of simulations using computer-based simulation. This research allows us to evaluate the impact of the use of the indicators in the design of the urban sets, on the economic and ecological plan. Using this method, we prove that an urban design, which carefully considered energetically, can contribute significantly to the preservation of the environment and the reduction of the consumption of energy.

Keywords: comfort, energy consumption, energy mastery, morpho-energetic indicators, simulation, sub-humid climate, urban sets

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Authors: Shantha Kumari Muniyandi, Johan Sohaili, Siti Suhaila Mohamad

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The aim of this study was to investigate the suitability of reusing nonmetallic printed circuit boards (PCBs) waste in recycled HDPE (rHDPE) in terms of toxicity and mechanical properties. A series of X-ray Fluorescence Spectrometry (XRF) analysis tests have been conducted on raw nonmetallic PCBs waste to determine the chemical compositions. It can be seen that the nonmetallic PCBs approximately 72% of glass fiber reinforced epoxy resin materials such as SiO2, Al2O3, CaO, MgO, BaO, Na2O, and SrO, 9.4% of metallic materials such as CuO, SnO2, and Fe2O3, and 6.53% of Br. Total Threshold Limit Concentration (TTLC) and Toxicity Characteristic Leaching Procedure (TCLP) tests also have been done to study the toxicity characteristics of raw nonmetallic PCB powders, rHDPE/PCB and virgin HDPE for comparison purposes. For both of the testing, Cu was identified as the highest metal element contained in raw PCBs with the concentration of 905 mg/kg and 59.09 mg/L for TTLC and TCLP, respectively. However, once the nonmetallic PCB was filled in rHDPE composites, the concentrations of Cu were reduced to 134 mg/kg for TTLC and to 3 mg/L for TCLP testing. For mechanical properties testing, incorporation of 40 wt% nonmetallic PCB into rHDPE has increased the flexural modulus and flexural strength by 140% and 36%, respectively. While, Izod Impact strength decreased steadily with incorporation of 10 – 40 wt% nonmetallic PCBs.

Keywords: nonmetallic printed circuit board, recycled HDPE, composites, mechanical properties, total threshold limit concentration, toxicity characteristic leaching procedure

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Authors: Riccardo Fratini, Riccardo Santini, Jacopo Serafini, Massimo Gennaretti, Stefano Panzieri

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This paper presents a nonlinear differential model, for a three-bladed horizontal axis wind turbine (HAWT) suited for control applications. It is based on a 8-dofs, lumped parameters structural dynamics coupled with a quasi-steady sectional aerodynamics. In particular, using the Euler-Lagrange Equation (Energetic Variation approach), the authors derive, and successively validate, such model. For the derivation of the aerodynamic model, the Greenbergs theory, an extension of the theory proposed by Theodorsen to the case of thin airfoils undergoing pulsating flows, is used. Specifically, in this work, the authors restricted that theory under the hypothesis of low perturbation reduced frequency k, which causes the lift deficiency function C(k) to be real and equal to 1. Furthermore, the expressions of the aerodynamic loads are obtained using the quasi-steady strip theory (Hodges and Ormiston), as a function of the chordwise and normal components of relative velocity between flow and airfoil Ut, Up, their derivatives, and section angular velocity ε˙. For the validation of the proposed model, the authors carried out open and closed-loop simulations of a 5 MW HAWT, characterized by radius R =61.5 m and by mean chord c = 3 m, with a nominal angular velocity Ωn = 1.266rad/sec. The first analysis performed is the steady state solution, where a uniform wind Vw = 11.4 m/s is considered and a collective pitch angle θ = 0.88◦ is imposed. During this step, the authors noticed that the proposed model is intrinsically periodic due to the effect of the wind and of the gravitational force. In order to reject this periodic trend in the model dynamics, the authors propose a collective repetitive control algorithm coupled with a PD controller. In particular, when the reference command to be tracked and/or the disturbance to be rejected are periodic signals with a fixed period, the repetitive control strategies can be applied due to their high precision, simple implementation and little performance dependency on system parameters. The functional scheme of a repetitive controller is quite simple and, given a periodic reference command, is composed of a control block Crc(s) usually added to an existing feedback control system. The control block contains and a free time-delay system eτs in a positive feedback loop, and a low-pass filter q(s). It should be noticed that, while the time delay term reduces the stability margin, on the other hand the low pass filter is added to ensure stability. It is worth noting that, in this work, the authors propose a phase shifting for the controller and the delay system has been modified as e^(−(T−γk)), where T is the period of the signal and γk is a phase shifting of k samples of the same periodic signal. It should be noticed that, the phase shifting technique is particularly useful in non-minimum phase systems, such as flexible structures. In fact, using the phase shifting, the iterative algorithm could reach the convergence also at high frequencies. Notice that, in our case study, the shifting of k samples depends both on the rotor angular velocity Ω and on the rotor azimuth angle Ψ: we refer to this controller as a spatial repetitive controller. The collective repetitive controller has also been coupled with a C(s) = PD(s), in order to dampen oscillations of the blades. The performance of the spatial repetitive controller is compared with an industrial PI controller. In particular, starting from wind speed velocity Vw = 11.4 m/s the controller is asked to maintain the nominal angular velocity Ωn = 1.266rad/s after an instantaneous increase of wind speed (Vw = 15 m/s). Then, a purely periodic external disturbance is introduced in order to stress the capabilities of the repetitive controller. The results of the simulations show that, contrary to a simple PI controller, the spatial repetitive-PD controller has the capability to reject both external disturbances and periodic trend in the model dynamics. Finally, the nominal value of the angular velocity is reached, in accordance with results obtained with commercial software for a turbine of the same type.

Keywords: wind turbines, aeroelasticity, repetitive control, periodic systems

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Authors: Samhani Ismail, Tahamina Begum, Faruque Reza, Zamzuri Idris, Hafizan Juahir, Jafri Malin Abdullah

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Holy Quran, a rhymed prosed scripture has a complete literary structure that exemplifies the peak of literary beauty. Memorizing of its verses could enhance one’s memory capacity and cognition while those who are listening to its recitation it is also believed that the Holy Quran alter brainwave producing neuronal excitation engaging with cognitive processes. 28 normal healthy subjects (male =14 & female = 14) were recruited and EEG recording was done using 128-electrode sensor net (Electrical Geosics, Inc.) with the impedance of ≤ 50kΩ. They listened to Sura Fatiha recited by Sheikh Qari Abdul Basit bin Abdus Samad. Arabic news and no sound were chosen as positive and negative control, respectively. The waveform was analysed by Fast Fourier Transform (FFT) to get the power in frequency bands. Bilateral frontal (F7, F8) and temporal region (T7, T8) showed decreased power significantly in alpha wave band in respondent stimulated by Sura Fatihah recitation reflects acoustic attention processing. However, decreased in alpha power in selective attention to memorized, and in familial but not memorized language, reveals the memorial processing in long-term memory. As a conclusion, Quranic recitation relates both cognitive element of memory and language in its listeners and memorizers.

Keywords: auditory stimulation, cognition, EEG, linguistic, memory, Quranic recitation

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Authors: Aklima Jesmin, Ubaidur Rob, M. Ashrafur Rahman

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Rohingya population of Arakan state in Myanmar are one the most persecuted ethnic minorities in this 21st century. According to the Universal Declaration of Human Rights (UDHR), all human beings are born free, equal in dignity and rights. However, these populations are systematically excluded from this universal proclamation of human rights as they are Rohingya, which signify ‘other’. Based on the accessible and available literatures about Rohingya issue, this study firstly found there are chronological pattern of human rights violations against the ethnic Rohingya which follows the pathology of the Holocaust in this 21st century of human civilization. These violations have been possible due to modern technology, bureaucracy which has been performed through authorization, routinization and dehumanization; not only in formal institutions but in the society as a whole. This kind of apparently never-ending situation poses any author with the problem of available many scientific articles. The most important sources are, therefore the international daily newspapers, social media and official webpage of the non-state actors for nitty-gritty day to day update. Although it challenges the validity and objectivity of the information, but to address the critical ongoing human rights violations against Rohingya population can become a base for further work on this issue. One of the aspects of this paper is to accommodate all the social movements since August 2017 to date. The findings of this paper is that even though it seemed only human rights violations occurred against Rohingya historically but, simultaneously the process of social movements had also started, can be traced more after the military campaign in 2017. Therefore, the Rohingya crisis can be conceptualized within one ‘campaign’ movement for justice, not as episodic events, especially within the Political Process Model than any other social movement theories. This model identifies that the role of international political movements as well as the role of non-state actors are more powerful than any other episodes of violence conducted against Rohinyga in reframing issue, blaming and shaming to Myanmar government and creating the strategic opportunities for social changes. The lack of empowerment of the affected Rohingya population has been found as the loop to utilize this strategic opportunity. Their lack of empowerment can also affect their capacity to reframe their rights and to manage the campaign for their justice. Therefore, this should be placed at the heart of the international policy agenda within the broader socio-political movement for the justice of Rohingya population. Without ensuring human rights of Rohingya population, achieving the promise of the united nation’s sustainable development goals - no one would be excluded – will be impossible.

Keywords: civilization, holocaust, human rights violation, military campaign, political process model, Rohingya population, sustainable development goal, social justice, social movement, strategic opportunity

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Authors: Muhammad Yahaya Ubale

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Substantial rate of urbanization as well as economic growth is the tasks and prospects of sustainability. Objectives of the paper are: to ascertain the fate of sustainability in urbanized cities and; to identify the challenges of land use array in urbanized cities. Methodology engaged in this paper employed the use of secondary data where articles, conference proceedings, seminar papers and literature materials were effectively used. The paper established the fact that while one thinks globally, it is reciprocal to act locally if at all sustainability should be achieved. The speed and scale of urbanization must be equal to natural and cost-effective deliberations. It also discovered a podium that allows a city to work together as an ideal conglomerate, engaging all city departments as a source of services, engaging residents, businesses, and contractors. It also revealed that city should act as a leader and partner within an urban region, engaging senior government officials, utilities, rural settlements, private sector stakeholders, NGOs, and academia. Cities should assimilate infrastructure system design and management to enhance efficiency of resource flows in an urban area. They should also coordinate spatial development; integrate urban forms and urban flows, combine land use, urban design, urban density, and other spatial attributes with infrastructural development. Finally, by 2050, urbanized cities alone could be consuming 140 billion tons of minerals, ores, fossil fuels and biomass annually (three times its current rate of consumption), sustainability can be accomplished through land use control, limited access to finite resources, facilities, utilities and services as well as property right and user charge.

Keywords: sustainability, land use array, urbanized cities, fate of sustainability and perseverance

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Authors: M. Kumpugdee-Vollrath, M. Tabatabaeifar, M. Helmis

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Shellac is a natural polyester resin secreted by insects. Pectins are natural, non-toxic and water-soluble polysaccharides extracted from the peels of citrus fruits or the leftovers of apples. Both polymers are allowed for the use in the pharmaceutical industry and as a food additive. SSB Aquagold® is the aqueous solution of shellac and can be used for a coating process as an enteric or controlled drug release polymer. In this study, tablets containing 10 mg methylene blue as a model drug were prepared with a rotary press. Those tablets were coated with mixtures of shellac and one of the pectin different types (i.e. CU 201, CU 501, CU 701 and CU 020) mostly in a 2:1 ratio or with pure shellac in a small scale fluidized bed apparatus. A stable, simple and reproducible three-stage coating process was successfully developed. The drug contents of the coated tablets were determined using UV-VIS spectrophotometer. The characterization of the surface and the film thickness were performed with the scanning electron microscopy (SEM) and the light microscopy. Release studies were performed in a dissolution apparatus with a basket. Most of the formulations were enteric coated. The dissolution profiles showed a delayed or sustained release with a lagtime of at least 4 h. Dissolution profiles of coated tablets with pure shellac had a very long lagtime ranging from 13 to 17.5 h and the slopes were quite high. The duration of the lagtime and the slope of the dissolution profiles could be adjusted by adding the proper type of pectin to the shellac formulation and by variation of the coating amount. In order to apply a coating formulation as a colon delivery system, the prepared film should be resistant against gastric fluid for at least 2 h and against intestinal fluid for 4-6 h. The required delay time was gained with most of the shellac-pectin polymer mixtures. The release profiles were fitted with the modified model of the Korsmeyer-Peppas equation and the Hixson-Crowell model. A correlation coefficient (R²) > 0.99 was obtained by Korsmeyer-Peppas equation.

Keywords: shellac, pectin, coating, fluidized bed, release, colon delivery system, kinetic, SEM, methylene blue

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Authors: D. Suman, M. Venkateshwara Rao

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Cancer is a disease caused by an uncontrolled division of abnormal cells in a part of the body, which is affecting millions of people leading to death. Even though there have been tremendous developments taken place over the last few decades the effective therapy for cancer is still not a reality. The existing techniques of cancer therapy are chemotherapy and radio therapy which are having their limitations in terms of the side effects, patient discomfort, radiation hazards and the localization of treatment. This paper describes a novel method for cancer therapy by using RF-hyperthermia application of nanoparticles. We have synthesized ferromagnetic nanoparticles and characterized by using XRD and TEM. These nanoparticles after the biocompatibility studies will be injected in to the body with a suitable tracer element having affinity to the specific tumor site. When RF energy is applied to the nanoparticles at the tumor site it produces heat of excess room temperature and nearly 41-45°C is sufficient to kill the tumor cells. We have designed a RF source generator provided with a temperature feedback controller to control the radiation induced temperature of the tumor site. The temperature control is achieved through a negative feedback mechanism of the thermocouple and a relay connected to the power source of the RF generator. This method has advantages in terms of its effect like localized therapy, less radiation, and no side effects. It has several challenges in designing the RF source provided with coils suitable for the tumour site, biocompatibility of the nanomaterials, cooling system design for the RF coil. If we can overcome these challenges this method will be a huge benefit for the society.

Keywords: hyperthermia, cancer therapy, RF source generator, nanoparticles

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Authors: Mark Pizzato

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How do ideas, images, and emotions in stage-plays and videos affect us? Do they evoke a greater awareness (or cognitive reappraisal of emotions) through possible shifts between left-cortical, right-cortical, and subcortical networks? To address these questions, this presentation summarizes the research of various neuroscientists, especially Bernard Baars and others involved in Global Workspace Theory, Matthew Lieberman in social neuroscience, Iain McGilchrist on left and right cortical functions, and Jaak Panksepp on the subcortical circuits of primal emotions. Through such research, this presentation offers an ‘inner theatre’ model of the brain, regarding major hubs of neural networks and our animal ancestry. It also considers recent experiments, by Mario Beauregard, on the cognitive reappraisal of sad, erotic, and aversive film clips. Finally, it applies the inner-theatre model and related research to survey results of theatre students who read and then watched the ‘To be or not to be’ speech in 8 different video versions (from stage and screen productions) of William Shakespeare’s Hamlet. Findings show that students become aware of left-cortical, right-cortical, and subcortical brain functions—and shifts between them—through staging and movie-making choices in each of the different videos.

Keywords: cognitive reappraisal, Hamlet, neuroscience, Shakespeare, theatre

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Authors: Zhang Qingzhong

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Though there exists an increasing number of research studies on the headquarters-subsidiary relationship, and within this context, there is a focus on subsidiaries' contributory role to multinational corporations (MNC), subsidiary autonomy, and the conditions under which autonomy exerts an effect on subsidiary performance still constitute a subject of debate in the literature. The objective of this research is to study the MNC subsidiary autonomy and performance relationship and the effect of subsidiary entrepreneurial orientation and trust on subsidiary autonomy in the China environment, a phenomenon that has not yet been studied. The research addresses the following three questions: (i) Is subsidiary autonomy associated with MNC subsidiary performance in the China environment? (ii) How do subsidiary entrepreneurship and its trust in headquarters affect the level of subsidiary autonomy and its relationship with subsidiary performance? (iii) Does subsidiary autonomy have a mediating effect on subsidiary performance with subsidiary’s entrepreneurship and trust in headquarters? In the present study, we have reviewed literature and conducted semi-structured interviews with multinational corporation (MNC) subsidiary senior executives in China. Building on our insights from the interviews and taking perspectives from four theories, namely the resource-based view (RBV), resource dependency theory, integration-responsiveness framework, and social exchange theory, as well as the extant articles on subsidiary autonomy, entrepreneurial orientation, trust, and subsidiary performance, we have developed a model and have explored the direct and mediating effects of subsidiary autonomy on subsidiary performance within the framework of the MNC. To test the model, we collected and analyzed data based on cross-industry two waves of an online survey from 102 subsidiaries of MNCs in China. We used structural equation modeling to test measurement, direct effect model, and conceptual framework with hypotheses. Our findings confirm that (a) subsidiary autonomy is positively related to subsidiary performance; (b) subsidiary entrepreneurial orientation is positively related to subsidiary autonomy; (c) subsidiary’s trust in headquarters has a positive effect on subsidiary autonomy; (d) subsidiary autonomy mediates the relationship between entrepreneurial orientation and subsidiary performance; (e) subsidiary autonomy mediates the relationship between trust and subsidiary performance. Our study highlights the important role of subsidiary autonomy in leveraging the resource of subsidiary entrepreneurial orientation and its trust relationship with headquarters to achieve high performance. We discuss the theoretical and managerial implications of the findings and propose directions for future research.

Keywords: subsidiary entrepreneurial orientation, trust, subsidiary autonomy, subsidiary performance

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Authors: Y. Long, L. Liu, K. V. Branin

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One challenge faced by procurement decision-maker during the acquisition process is how to compare similar products from different suppliers and allocate orders among different products or services. This work focuses on allocating orders among multiple suppliers considering rebate. The objective function is to minimize the total acquisition cost including purchasing cost and rebate benefit. Rebate benefit is complex and difficult to estimate at the ordering step. Rebate rules vary for different suppliers and usually change over time. In this work, we developed a system to collect the rebate policies, standardized the rebate policies and developed two-stage optimization models for ordering allocation. Rebate policy with multi-tiers is considered in modeling. The discontinuous cost function of rebate benefit is formulated for different scenarios. A piecewise linear function is used to approximate the discontinuous cost function of rebate benefit. And a Mixed Integer Programing (MIP) model is built for order allocation problem with multi-tier rebate. A case study is presented and it shows that our optimization model can reduce the total acquisition cost by considering rebate rules.

Keywords: discontinuous cost function, mixed integer programming, optimization, procurement, rebate

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Authors: Jiawen Wang, Qijun Chen

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The performance of most machine-learning methods for image inpainting depends on the quantity and quality of the training samples. However, it is very expensive or even impossible to obtain a great number of training samples in many scenarios. In this paper, an image inpainting model based on a generative adversary network (GAN) is constructed for the cases when the number of training samples is small. Firstly, a feature extraction network (F-net) is incorporated into the GAN network to utilize the available information of the inpainting image. The weighted sum of the extracted feature and the random noise acts as the input to the generative network (G-net). The proposed network can be trained well even when the sample size is very small. Secondly, in the phase of the completion for each damaged image, a genetic algorithm is designed to search an optimized noise input for G-net; based on this optimized input, the parameters of the G-net and F-net are further learned (Once the completion for a certain damaged image ends, the parameters restore to its original values obtained in the training phase) to generate an image patch that not only can fill the missing part of the damaged image smoothly but also has visual semantics.

Keywords: image inpainting, generative adversary nets, genetic algorithm, small-sample size

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Authors: Tofigh Hamidavi, Sepehr Abrishami, Pasquale Ponterosso, David Begg

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Structural design and analysis is an important and time-consuming process, particularly at the conceptual design stage. Decisions made at this stage can have an enormous effect on the entire project, as it becomes ever costlier and more difficult to alter the choices made early on in the construction process. Hence, optimisation of the early stages of structural design can provide important efficiencies in terms of cost and time. This paper suggests a structural design optimisation (SDO) framework in which Genetic Algorithms (GAs) may be used to semi-automate the production and optimisation of early structural design alternatives. This framework has the potential to leverage conceptual structural design innovation in Architecture, Engineering and Construction (AEC) projects. Moreover, this framework improves the collaboration between the architectural stage and the structural stage. It will be shown that this SDO framework can make this achievable by generating the structural model based on the extracted data from the architectural model. At the moment, the proposed SDO framework is in the process of validation, involving the distribution of an online questionnaire among structural engineers in the UK.

Keywords: building information, modelling, BIM, genetic algorithm, GA, architecture-engineering-construction, AEC, optimisation, structure, design, population, generation, selection, mutation, crossover, offspring

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Authors: Medina Muñoz Lina Rocio

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The purpose of this paper is to examine the debates related to the harmonization of intellectual property rights on plant material, the corporate governance of the seed market in Colombia and the political economy of seeds defended by indigenous communities. In recent years, the commodification of seeds through genetic engineering and political intellectual property, codified as a result of the implementation of the Free Trade Agreement with the United States, has come into conflict with the traditional production of seeds carried out by small farmers and indigenous populations. Agricultural and food practices. In order to understand the ontological dimension of conflicts over seeds, it is necessary to analyze the conceptions that indigenous communities have about good, which they consider a common element of their social organization and define them as sentient beings. Therefore, through a multiple approach, in which the intellectual property policy, the ecological aspects of seed production and the political ontology of indigenous communities are interwoven, I intend to present the discussions held by the actors involved and present the strategies of small producers to protect their interests. It demonstrates that communities have begun to organize social movements to protect such interests and have questioned the philosophy of GM corporate agriculture as a pro-life movement. Finally, it is argued that the conservation of 'traditional' seeds of the communities is an effective strategy to support their struggles for territory, identity, food sovereignty and self-determination.

Keywords: intellectual property rights, intellectual property, traditional knowledge, food safety

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Authors: Dheyaa Wajid Abbood, Mohanad Salih Farhan, Awadh E. Ajeel

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The basic goal of this study is the production of cheap building elements from plastic waste. environmentally friendly and of good thermal insulation. The study depends on the addition of plastic waste as aggregates to the mixes of concrete at different percentages by weight (12 percentages) to produce lightweight aggregate concrete the density (1095 - 1892) kg/m3.The experimental work includes 120 specimens of concrete 72 cubes (150*150*150)mm, 48 cylinder (150*300) mm. The results obtained for concrete were for local raw materials without any additional materials or treatment. The mechanical and thermal properties determined were (compressive strength, static modulus of elasticity, density, thermal conductivity (k), specific heat capacity (Cp), thermal expansion (α) after (7) days of curing at 20 0C. The increase in amount of plastic waste decreases the density of concrete which leads to decrease in the mechanical and to improvement in thermal properties. The average measured static modulus of elasticity are found less than the predicted static modulus of elasticity and splitting tensile strength (ACI 318-2008 and ACI 213R-2003). All cubes specimens when exposed to heat at (200, 400, 600 0C), the compressive strength of all mixes decreases gradually at 600 0C, the strength of lightweight aggregate concrete were disintegrated. Lightweight aggregate concrete is about 25% lighter than normal concrete in dead load, and to the improve the properties of thermal insulation of building blocks.

Keywords: LWAC, plastic waste, thermal property, thermal insulation

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Authors: Yiğit Gürler, Berkay Türkcan İmrağ, Taylan Güçkıran, İbrahim Şimşek, Alper Taşdemirci

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Paper honeycombs, which is a sandwich structure, consists of two liner faces and one paper honeycomb core. These materials are widely used in the packaging industry due to their low cost, low weight, good energy absorption capabilities and easy recycling properties. However, to provide maximum protection to the products in cases such as the drop of the packaged products, the mechanical behavior of these materials should be well known at the packaging design stage. In this study, the necessary input parameters for the modeling study were obtained by performing compression tests in the through-thickness and in-plane directions of paper-based honeycomb sandwich structures. With the obtained parameters, homogeneous and micro-mechanical numerical models were developed in the Ls-Dyna environment. The material card used for the homogeneous model is MAT_MODIFIED_HONEYCOMB, and the material card used for the micromechanical model is MAT_PIECEWISE_LINEAR_PLASTICITY. As a result, the effectiveness of homogeneous and micromechanical modeling approaches for paper-based honeycomb sandwich structure was investigated using force-displacement curves. Densification points and peak points on these curves will be compared.

Keywords: environmental packaging, mechanical characterization, Ls-Dyna, sandwich structure

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Authors: Napasri Suwanajote

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The purposes of this research were to analyse and evaluate successful factors in OTOP production process for the developing of learning centre on OTOP production process based on Sufficiency Economic Philosophy for sustainable life quality. The research has been designed as a qualitative study to gather information from 30 OTOP producers in Bangkontee District, Samudsongkram Province. They were all interviewed on 3 main parts. Part 1 was about the production process including 1) production 2) product development 3) the community strength 4) marketing possibility and 5) product quality. Part 2 evaluated appropriate successful factors including 1) the analysis of the successful factors 2) evaluate the strategy based on Sufficiency Economic Philosophy and 3) the model of learning centre on OTOP production process based on Sufficiency Economic Philosophy for sustainable life quality. The results showed that the production did not affect the environment with potential in continuing standard quality production. They used the raw materials in the country. On the aspect of product and community strength in the past 1 year, it was found that there was no appropriate packaging showing product identity according to global market standard. They needed the training on packaging especially for food and drink products. On the aspect of product quality and product specification, it was found that the products were certified by the local OTOP standard. There should be a responsible organization to help the uncertified producers pass the standard. However, there was a problem on food contamination which was hazardous to the consumers. The producers should cooperate with the government sector or educational institutes involving with food processing to reach FDA standard. The results from small group discussion showed that the community expected high education and better standard living. Some problems reported by the community included informal debt and drugs in the community. There were 8 steps in developing the model of learning centre on OTOP production process based on Sufficiency Economic Philosophy for sustainable life quality.

Keywords: production process, OTOP, sufficiency economic philosophy, marketing management

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Authors: Bahare Askarian, Suchithra Rajendran

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Maintaining the freshness and quality of perishable goods during distribution is a critical challenge for logistics companies. This study presents a comprehensive framework aimed at optimizing the distribution of perishable goods through a mathematical model of the Transportation Inventory Location Routing Problem (TILRP). The model incorporates the impact of product age on customer demand, addressing the complexities associated with inventory management and routing. To tackle this problem, we develop both simple and hybrid metaheuristic algorithms designed for small- and medium-scale scenarios. The hybrid algorithm combines Biogeographical Based Optimization (BBO) algorithms with local search techniques to enhance performance in small- and medium-scale scenarios, extending our approach to larger-scale challenges. Through extensive numerical simulations and sensitivity analyses across various scenarios, the performance of the proposed algorithms is evaluated, assessing their effectiveness in achieving optimal solutions. The results demonstrate that our algorithms significantly enhance distribution efficiency, offering valuable insights for logistics companies striving to improve their perishable goods supply chains.

Keywords: perishable goods, meta-heuristic algorithm, vehicle problem, inventory models

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Authors: R. Hasterok, A. Betekhtin, N. Borowska, A. Braszewska-Zalewska, E. Breda, K. Chwialkowska, R. Gorkiewicz, D. Idziak, J. Kwasniewska, M. Kwasniewski, D. Siwinska, A. Wiszynska, E. Wolny

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In contrast to animals, the organisation of plant genomes at the cytomolecular level is still relatively poorly studied and understood. However, the Brachypodium genus in general and B. distachyon in particular represent exceptionally good model systems for such study. This is due not only to their highly desirable ‘model’ biological features, such as small nuclear genome, low chromosome number and complex phylogenetic relations, but also to the rapidly and continuously growing repertoire of experimental tools, such as large collections of accessions, WGS information, large insert (BAC) libraries of genomic DNA, etc. Advanced cytomolecular techniques, such as fluorescence in situ hybridisation (FISH) with evermore sophisticated probes, empowered by cutting-edge microscope and digital image acquisition and processing systems, offer unprecedented insight into chromatin organisation at various phases of the cell cycle. A good example is chromosome painting which uses pools of chromosome-specific BAC clones, and enables the tracking of individual chromosomes not only during cell division but also during interphase. This presentation outlines the present status of molecular cytogenetic analyses of plant genome structure, dynamics and evolution using B. distachyon and some of its relatives. The current projects focus on important scientific questions, such as: What mechanisms shape the karyotypes? Is the distribution of individual chromosomes within an interphase nucleus determined? Are there hot spots of structural rearrangement in Brachypodium chromosomes? Which epigenetic processes play a crucial role in B. distachyon embryo development and selective silencing of rRNA genes in Brachypodium allopolyploids? The authors acknowledge financial support from the Polish National Science Centre (grants no. 2012/04/A/NZ3/00572 and 2011/01/B/NZ3/00177)

Keywords: Brachypodium, B. distachyon, chromosome, FISH, molecular cytogenetics, nucleus, plant genome organisation

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Authors: Rosa Christodoulaki, Irene Koronaki, Panagiotis Tsekouras

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The aim of this study is to analyze the energy performance of a spherical Stationary Reflector / Tracking Absorber (SRTA) solar concentrator. This type of collector consists of a segment of a spherical mirror placed in a stationary position facing the sun and a cylindrical absorber that tracks the sun by a simple pivoting motion about the center of curvature of the reflector. The energy analysis is performed through the development of a dynamic simulation model in TRNSYS software that calculates the annual heat production and the efficiency of the SRTA solar concentrator. The effect of solar concentrator design features and characteristics, such the reflector material, the reflector diameter, the receiver type, the solar radiation level and the concentration ratio, are discussed in details. Moreover, the energy performance curve of the SRTA solar concentrator, for various temperature differences between the mean fluid temperature and the ambient temperature and radiation intensities is drawn. The results are shown in diagrams, visualizing the effect of solar, optical and thermal parameters to the overall performance of the SRTA solar concentrator throughout the year. The analysis indicates that the SRTA solar concentrator can operate efficiently under a wide range of operating conditions.

Keywords: concentrating solar collector, energy analysis , stationary reflector, tracking absorber

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Authors: Jaeseung Lee, Muhammad Faizan Chinannai, Mohamed Hassan Gundu, Hyunchul Ju

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In this paper, we numerically investigated the effect of metal foams on a real scale 242.57cm2 (19.1 cm × 12.7 cm) polymer electrolyte membrane fuel cell (PEFCs) using a three-dimensional two-phase PEFC model to substantiate design approach for PEFCs using metal foam as the flow distributor. The simulations were conducted under the practical low humidity hydrogen, and air gases conditions in order to observe the detailed operation result in the PEFCs using the serpentine flow channel in the anode and metal foam design in the cathode. The three-dimensional contours of flow distribution in the channel, current density distribution in the membrane and hydrogen and oxygen concentration distribution are provided. The simulation results revealed that the use of highly porous and permeable metal foam can be beneficial to achieve a more uniform current density distribution and better hydration in the membrane under low inlet humidity conditions. This study offers basic directions to design channel for optimal water management of PEFCs.

Keywords: polymer electrolyte fuel cells, metal foam, real-scale, numerical model

Procedia PDF Downloads 245

Authors: Zikra Faiz, Zaheer Asghar, Nisar Abid

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Information and Communication Technologies (ICTs) includes computers, the Internet, and electronic delivery systems such as televisions, radios, multimedia, and overhead projectors etc. In the modern world, ICTs is considered as an essential element of the teaching-learning process. The study was aimed to discover the usage of ICTs in Special Education Institutions for Visually Impaired students, Lahore, Pakistan. Objectives of the study were to explore the problems faced by teachers while using ICT in the classroom. The study was phenomenology in nature; a qualitative survey method was used through a semi-structured interview protocol developed by the researchers. The sample comprised of eighty faculty members selected through a purposive sampling technique. Data were analyzed through thematic analysis technique with the help of open coding. The study findings revealed that multimedia, projectors, computers, laptops and LEDs are used in special education institutes to enhance the teaching-learning process. Teachers believed that ICTs could enhance the knowledge of visually impaired students and every student should use these technologies in the classroom. It was concluded that multimedia, projectors and laptops are used in classroom by teachers and students. ICTs can promote effectively through the training of teachers and students. It was suggested that the government should take steps to enhance ICTs in teacher training and other institutions by pre-service and in-service training of teachers.

Keywords: information and communication technologies, in-services teachers, special education institutions

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Authors: Khanh To Duc, Monica Chiogna, Gianfranco Adimari

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With three diagnostic categories, assessment of the performance of diagnostic tests is achieved by the analysis of the receiver operating characteristic (ROC) surface, which generalizes the ROC curve for binary diagnostic outcomes. The volume under the ROC surface (VUS) is a summary index usually employed for measuring the overall diagnostic accuracy. When the true disease status can be exactly assessed by means of a gold standard (GS) test, unbiased nonparametric estimators of the ROC surface and VUS are easily obtained. In practice, unfortunately, disease status verification via the GS test could be unavailable for all study subjects, due to the expensiveness or invasiveness of the GS test. Thus, often only a subset of patients undergoes disease verification. Statistical evaluations of diagnostic accuracy based only on data from subjects with verified disease status are typically biased. This bias is known as verification bias. Here, we consider the problem of correcting for verification bias when continuous diagnostic tests for three-class disease status are considered. We assume that selection for disease verification does not depend on disease status, given test results and other observed covariates, i.e., we assume that the true disease status, when missing, is missing at random. Under this assumption, we discuss several solutions for ROC surface analysis based on imputation and re-weighting methods. In particular, verification bias-corrected estimators of the ROC surface and of VUS are proposed, namely, full imputation, mean score imputation, inverse probability weighting and semiparametric efficient estimators. Consistency and asymptotic normality of the proposed estimators are established, and their finite sample behavior is investigated by means of Monte Carlo simulation studies. Two illustrations using real datasets are also given.

Keywords: imputation, missing at random, inverse probability weighting, ROC surface analysis

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Authors: Samba Lamine Cisse, Cheick Oumar Tangara, Seynabou Sissoko, Mahamadou Diakite, Seydou Doumbia

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Background: Financial management of a scientific research center is a crucial element in achieving ambitious scientific goals. It can be a driving force for research success, but it also has shortcomings that are important to understand. This study focuses on the crucial aspects of financial management in the context of scientific research centers, more specifically the USTTB (UCRC) in Mali in terms of strengths and weaknesses. Methodology: This study concerns the case of the UCRC, one of the USTTB's research centers. It is a qualitative study based on years of experience in project management at the USTTB, and on analyses and interpretations of everyday activities. Result: It offers practical recommendations for improving the financial stability of research institutions, thereby contributing to their mission of promoting scientific research and innovation. Scientific research centers play a crucial role in the development of knowledge, and their effective operation largely depends on the appropriate management of their financial resources. It begins with an in-depth analysis of UCRC's typical financial structure, highlighting its types and sources of funding, followed by an analysis of the strengths and weaknesses of its current financial management system. Conclusion: Financial management of a scientific research center is essential to ensure the continuity of research activities, the development of innovative projects and the achievement of scientific objectives. Adaptive financial management focused on efficiency, diversification of funding and risk control. They are essential to meeting these challenges and fostering excellence in scientific research.

Keywords: financial, management, strengths, weaknesses, recommendations

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Authors: Haitao Yang, Jianming Lv, Fei Xu, Xintong Wang, Yilin Huang, Lanting Xia, Xuewu Zhu

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Given a fixed fund, purchasing fewer hosts of higher capability or inversely more of lower capability is a must-be-made trade-off in practices for building a Hadoop big data platform. An exploratory study is presented for a Housing Big Data Platform project (HBDP), where typical big data computing is with SQL queries of aggregate, join, and space-time condition selections executed upon massive data from more than 10 million housing units. In HBDP, an empirical formula was introduced to predict the performance of host clusters potential for the intended typical big data computing, and it was shaped via a regression approach. With this empirical formula, it is easy to suggest an optimal cluster configuration. The investigation was based on a typical Hadoop computing ecosystem HDFS+Hive+Spark. A proper metric was raised to measure the performance of Hadoop clusters in HBDP, which was tested and compared with its predicted counterpart, on executing three kinds of typical SQL query tasks. Tests were conducted with respect to factors of CPU benchmark, memory size, virtual host division, and the number of element physical host in cluster. The research has been applied to practical cluster procurement for housing big data computing.

Keywords: Hadoop platform planning, optimal cluster scheme at fixed-fund, performance predicting formula, typical SQL query tasks

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Authors: Yu Song, Yuefei Jin

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Urban public transportation can be integrated when there is an efficient connection between urban rail lines, however, there are currently no effective or quick solutions being investigated for this connection. This paper analyzes the space-time distribution and travel demand of passenger connection travel based on taxi track data and data from the road network, excavates potential bus connection stations based on potential connection demand data, and introduces the link growth probability model in the complex network to solve the basic connection bus lines in order to ascertain the direction of the bus lines that are the most connected given the demand characteristics. Then, a tree view exhaustive approach based on constraints is suggested based on graph theory, which can hasten the convergence of findings while doing chain calculations. This study uses WEI QU NAN Station, the Xi'an Metro Line 2 terminal station in Shaanxi Province, as an illustration, to evaluate the model's and the solution method's efficacy. According to the findings, 153 prospective stations have been dug up in total, the feeder bus network for the entire line has been laid out, and the best route adjustment strategy has been found.

Keywords: feeder bus, route optimization, link growth probability, the graph theory

Procedia PDF Downloads 81

Authors: Kushal Kumar Chode

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Increase in demand for fuel saving and demand for faster vehicles with decent fuel economy, researchers around the world started investigating in various passive flow control devices to improve the fuel efficiency of vehicles. In this paper, A roof fairing was investigated for reducing the aerodynamic drag of a bluff body. The bluff body considered for this work is Ahmed model with a rake angle of 25deg was and subjected to flow with a velocity of 40m/s having Reynolds number of 2.68million was analysed using a commercial Computational Fluid Dynamic (CFD) code Star CCM+. It was evident that pressure drag is the main source of drag on an Ahmed body from the initial study. Adding a roof fairing has delayed the flow separation and resulted in delaying wake formation, thus improving the pressure in near weak and reducing the wake region. Adding a roof fairing of height and length equal to 1/7H and 1/3L respectively has shown a drag reduction by 9%. However, an optimised fairing, which was obtained by changing height, length and width by 5% increase, recorded a drag reduction close 12%.

Keywords: Ahmed model, aerodynamic drag, passive flow control, roof fairing, wake formation

Procedia PDF Downloads 446

Authors: Hammad Khan, Wookeun Bae

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The objective of this study was to achieve, optimize and control the highly loaded and efficient nitrite production having suitability for autotrophic and heterotrophic denitritation. A lab scale CSTR for partial and full nitritation was operated to treat the livestock manure digester liquor having an ammonium concentration of ~2000 mg-NH4+-N/L and biodegradable contents of ~0.8 g-COD/L. The experiments were performed at 30°C, pH: 8.0, DO: 1.5 mg/L and SRT ranging from 7-20 days. After 125 days operation, >95% nitrite buildup having the ammonium loading rate of ~3.2 kg-NH4+-N/m3-day was seen with almost complete ammonium conversion. On increasing the loading rate further (i-e, from 3.2-6.2 kg-NH4+-N/m3-day), stability of the system remained unaffected. On decreasing the pH from 8 to 7.5 and further 7.2, removal rate can be easily controlled as 95%, 75% and even 50%. Results demonstrated that nitritation stability and desired removal rates are controlled by a balance of simultaneous inhibition by FA & FNA, pH affect and DO limitation. These parameters proved to be effective even to produce an appropriate influent for anammox. In addition, a mathematical model, identified through the occurring biological reactions, is proposed to optimize the full and partial nitritation process. The proposed model present relationship between pH, ammonium and produced nitrite for full and partial nitritation under the varying concentrations of DO, and simultaneous inhibition by FA and FNA.

Keywords: stable nitritation, high loading, autrophic denitritation, hetrotrophic denitritation

Procedia PDF Downloads 278

Authors: Mahdi Allaoua Seklab, Süleyman BaşTürk

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In the quest to enhance coastal environmental health, this study introduces a fully autonomous beach cleaning machine, a breakthrough in leveraging green energy and advanced artificial intelligence for ecological preservation. Designed to operate independently, the machine is propelled by a solar-powered system, underscoring a commitment to sustainability and the use of renewable energy in autonomous robotics. The vehicle's autonomous navigation is achieved through a sophisticated integration of LIDAR and a camera system, utilizing an SSD MobileNet V2 object detection model for accurate and real-time trash identification. The SSD framework, renowned for its efficiency in detecting objects in various scenarios, is coupled with the lightweight and precise highly MobileNet V2 architecture, making it particularly suited for the computational constraints of on-board processing in mobile robotics. Training of the SSD MobileNet V2 model was conducted on Google Colab, harnessing cloud-based GPU resources to facilitate a rapid and cost-effective learning process. The model was refined with an extensive dataset of annotated beach debris, optimizing the parameters using the Adam optimizer and a cross-entropy loss function to achieve high-precision trash detection. This capability allows the machine to intelligently categorize and target waste, leading to more effective cleaning operations. This paper details the design and functionality of the beach cleaning machine, emphasizing its autonomous operational capabilities and the novel application of AI in environmental robotics. The results showcase the potential of such technology to fill existing gaps in beach maintenance, offering a scalable and eco-friendly solution to the growing problem of coastal pollution. The deployment of this machine represents a significant advancement in the field, setting a new standard for the integration of autonomous systems in the service of environmental stewardship.

Keywords: autonomous beach cleaning machine, renewable energy systems, coastal management, environmental robotics

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Authors: Syafinatul Fitri

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Cakrawala Baca is one of social organization in Indonesia that realize to transform its organization into social enterprise to create more sustainable organization that result more sustainable social impact. Cakrawala Baca implements voluntary system for its organization and it has passive social target. It funds its program by several fund rising activities that depend on donors or sponsor. Therefore social activity that held does not create sustainable social impact. It is different with social enterprise that usually more independent in funding its activity through social business and implement active social target and professional work for organization member. Therefore social enterprise can sustain its organization and then able to create sustainable social impact. Developing transformation model from social movement into social enterprise is the focus of this study. To achieve the aim of study, benchmark approach from successful social enterprise in Indonesia that has previously formed as social movement is employed. The benchmark is conducted through internal and external scanning that result the understanding of how they transformed into social enterprise. After understanding SAM and Agritektur transformation, transformation pattern is formulated based on their transformation similarities. This transformation pattern will be implemented to formulate the transformation plan for Cakrawala Baca to be a social enterprise.

Keywords: social movement/social organization, non-profit organization (NPO), social enterprise, transformation, Benchmarks approach

Procedia PDF Downloads 515