Search results for: quantum transport

Authors: W. Thongkham, K. Sinthiptharakoon, K. Tantisantisom, A. Klamchuen, P. Khanchaitit, K. Jiramitmongkon, C. Lertsatitthanakorn, M. Liangruksa

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Due to demands of sustainable energy, thermoelectricity converting waste heat into electrical energy has become one of the intensive fields of worldwide research. However, such harvesting technology has shown low device performance in the temperature range below 150℃. In this work, a hybrid nanowire of inorganic bismuth telluride (Bi₂Te₃) and organic poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) synthesized using a simple in-situ one-pot synthesis, enhancing efficiency of the nanowire-incorporated PEDOT:PSS-based thermoelectric converter is highlighted. Since the improvement is ascribed to the increased electrical conductivity of the thermoelectric host material, the individual hybrid nanowires are investigated using voltage-dependent conductive atomic force microscopy (CAFM) and spectroscopy (CAFS) considering that the electrical transport measurement can be performed either on insulating or conducting areas of the sample. Correlated with detailed chemical information on the crystalline structure and compositional profile of the nanowire core-shell structure, an electrical transporting pathway through the nanowire and the corresponding electronic-band structure have been determined, in which the native oxide layer on the Bi₂Te₃ surface is not considered, and charge conduction on the topological surface states of Bi₂Te₃ is suggested. Analyzing the core-shell nanowire synthesized using the conventional mixing of as-prepared Bi₂Te₃ nanowire with PEDOT:PSS for comparison, the oxide-removal effect of the in-situ encapsulating polymeric layer is further supported. The finding not only provides a structural information for mechanistic determination of the thermoelectricity, but it also encourages new approach toward more appropriate encapsulation and consequently higher efficiency of the nanowire-based thermoelectric generation.

Keywords: electrical transport measurement, hybrid Bi₂Te₃-PEDOT:PSS nanowire, nanoencapsulation, thermoelectricity, topological insulator

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Authors: Christina Jery, R. K. Anjana, D. N. Arnepalli, R. Sobha

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Modern landfills employ a composite liner consisting of a geomembrane overlying a compacted clay liner (CCL) or a geosynthetic clay liner (GCL) as a barrier system. The primary function of a barrier system is to control the contaminant transport from the leachate (dissolved phase) and landfill gas (vapour phase) out of the landfill thereby minimizing the environmental impact. This study is undertaken to investigate the diffusive migration of VOCs through composite liners. VOCs are known hazardous air pollutants were often existing in both the vapour phase and dissolved phase. These compounds are known to diffuse readily through the polymeric geomembranes. The objective of the research is to develop a comprehensive data set of diffusive parameters involved in the diffusion of VOCs in the composite liner (1.5 mm HDPE geomembrane overlying a 30mm compacted clay layer). For this purpose, the study aims to develop a new experimental setup for determining the diffusion characteristics. The key parameters of diffusion (partitioning, diffusion and permeation coefficients) are examined. The diffusion tests are carried out both in aqueous and vapor phase. Finally, an attempt is also made to study the effect of low temperature on the diffusion characteristics.

Keywords: diffusion, sorption, organic compounds, composite liners, geomembrane

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Authors: Faezeh Eslamian, Zhiming Qi, Michael J. Tate

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Phosphorus losses from agricultural fields through leaching is one of the main contributors to eutrophication of lakes in Quebec as well as North America. The main objective of this study is to evaluate the application of high calcium hydrated lime as a soil amendment in reducing the subsurface transport of phosphorus to water bodies by studying the interactions between phosphorus leaching and lime application in three common agricultural soil textures (sandy loam, loam and clay loam) in Quebec. For this purpose, 6 intact soil columns of 10 cm diameter and 20 cm deep were taken from each of the three different soil textured agricultural fields. Lime (high calcium hydrated lime) was applied to the top 5 cm of half of the intact soil columns while the rest were left as controls. The columns were leached with artificial rainwater in-consecutively at a rate of 3 mm h-1 over a 90-day period. The total amount of water added was equal to the average total rainfall of the region in fall. The leachate samples were collected daily and analyzed for dissolved reactive phosphorus, total dissolved phosphorus, total phosphorus, pH, electrical conductivity, calcium, magnesium, potassium and iron. The results showed that lime was able to significantly reduce dissolved reactive phosphorus concentrations in the leachates by 70 and 40 percent in sandy loam and loam soil columns, respectively, while phosphorus concentration in the clay loam soil leachates were increased by 40 percent. The calcium in lime has P-binding capabilities. Soil chemical properties in sandy and loamy soils can affect phosphorus leaching, whereas, transport mechanisms in clay soils with macropores dominate phosphorus leaching behaviors. The presence of preferential pathways and cracks in the clay soil columns has led to a quick transport of phosphorus through the soil and the less contact time with the soil matrix, therefore, causing less opportunity for P sorption and larger P release. Application of lime to agricultural fields can be considered as a promising measure in mitigating phosphorus loss from sandy loam and loam soils.

Keywords: leaching, lime, phosphorus, soil texture

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Authors: Siti Indati Mustapa, Hussain Ali Bekhet

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Global CO2 emission and increasing fuel consumption to meet energy demand requirement has become a threat in recent decades. Effort to reduce the CO2 emission is now a matter of priority in most countries of the world including Malaysia. Transportation has been identified as the most intensive sector of carbon-based fuels and achievement of the voluntary target to meet 40% carbon intensity reduction set at the 15th Conference of the Parties (COP15) means that the emission from the transport sector must be reduced accordingly. This posed a great challenge to Malaysia and effort has to be made to embrace suitable and appropriate energy policy for sustainable energy and emission reduction of this sector. The focus of this paper is to analyse the trends of Malaysia’s energy consumption and emission of four different transport sub-sectors (road, rail, aviation and maritime). Underlying factors influencing the growth of energy consumption and emission trends are discussed. Besides, technology status towards energy efficiency in transportation sub-sectors is presented. By reviewing the existing policies and trends of energy used, the paper highlights prospective policy options towards achieving emission reduction in the transportation sector.

Keywords: CO2 emissions, transportation sector, fuel consumption, energy policy, Malaysia

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Authors: Tomas Berhanu Bekele

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Traffic congestion is one of the main problems related to transportation in developed as well as developing countries. Traffic control systems are based on the idea of avoiding traffic instabilities and homogenizing traffic flow in such a way that the risk of accidents is minimized and traffic flow is maximized. Lately, Intelligent Transport Systems (ITS) has become an important area of research to solve such road traffic-related issues for making smart decisions. It links people, roads and vehicles together using communication technologies to increase safety and mobility. Moreover, accurate prediction of road traffic is important to manage traffic congestion. The aim of this study is to develop an ANN model for the prediction of traffic flow and to compare the ANN model with the linear regression model of traffic flow predictions. Data extraction was carried out in intervals of 15 minutes from the video player. Video of mixed traffic flow was taken and then counted during office work in order to determine the traffic volume. Vehicles were classified into six categories, namely Car, Motorcycle, Minibus, mid-bus, Bus, and Truck vehicles. The average time taken by each vehicle type to travel the trap length was measured by time displayed on a video screen.

Keywords: intelligent transport system (ITS), traffic flow prediction, artificial neural network (ANN), linear regression

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Authors: S. Jayasinghe, R. B. N. Dissanayake

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Optimization modelling together with the Network models and Linear Programming techniques is a powerful tool in problem solving and decision making in real world applications. This study developed a mathematical model to optimize the net profit by minimizing the transportation cost. This model focuses the transportation among decentralized production plants to a centralized distribution centre and then the distribution among island wide agencies considering the customer satisfaction as a requirement. This company produces basically 9 types of food items with 82 different varieties and 4 types of non-food items with 34 different varieties. Among 6 production plants, 4 were located near the city of Mawanella and the other 2 were located in Galewala and Anuradhapura cities which are 80 km and 150 km away from Mawanella respectively. The warehouse located in the Mawanella was the main production plant and also the only distribution plant. This plant distributes manufactured products to 39 agencies island-wide. The average values and average amount of the goods for 6 consecutive months from May 2013 to October 2013 were collected and then average demand values were calculated. The following constraints are used as the necessary requirement to satisfy the optimum condition of the model; there was one source, 39 destinations and supply and demand for all the agencies are equal. Using transport cost for a kilometer, total transport cost was calculated. Then the model was formulated using distance and flow of the distribution. Network optimization and linear programming techniques were used to originate the model while excel solver is used in solving. Results showed that company requires total transport cost of Rs. 146, 943, 034.50 to fulfil the customers’ requirement for a month. This is very much less when compared with data without using the model. Model also proved that company can reduce their transportation cost by 6% when distributing to island-wide customers. Company generally satisfies their customers’ requirements by 85%. This satisfaction can be increased up to 97% by using this model. Therefore this model can be used by other similar companies in order to reduce the transportation cost.

Keywords: mathematical model, network optimization, linear programming

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Authors: R. Pravin Kumar, L. Roopa

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Enzymes are molecular machines used in various industries such as pharmaceuticals, cosmetics, food and animal feed, paper and leather processing, biofuel, and etc. Nevertheless, this has been possible only by the breath-taking efforts of the chemists and biologists to evolve/engineer these mysterious biomolecules to work the needful. Main agenda of this enzyme engineering project is to derive screening and selection tools to obtain focused libraries of enzyme variants with desired qualities. The methodologies for this research include the well-established directed evolution, rational redesign and relatively less established yet much faster and accurate insilico methods. This concept was initiated as a Receptor Rependent-4Dimensional Quantitative Structure Activity Relationship (RD-4D-QSAR) to predict kinetic properties of enzymes and extended here to study transaminase by a 7D QSAR approach. Induced-fit scenarios were explored using Quantum Mechanics/Molecular Mechanics (QM/MM) simulations which were then placed in a grid that stores interactions energies derived from QM parameters (QMgrid). In this study, the mutated enzymes were immersed completely inside the QMgrid and this was combined with solvation models to predict descriptors. After statistical screening of descriptors, QSAR models showed > 90% specificity and > 85% sensitivity towards the experimental activity. Mapping descriptors on the enzyme structure revealed hotspots important to enhance the enantioselectivity of the enzyme.

Keywords: QMgrid, QM/MM simulations, RD-4D-QSAR, transaminase

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Authors: Mozhgan Aliakbari, Sara Moridpour

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In recent years, much attention has been given to truck drivers’ fatigue management. Long working hours negatively influence truck drivers’ physiology, health, and safety. However, there is little empirical research in the heavy vehicle transport sector in Australia to identify the influence of working hours’ management on drivers’ fatigue and consequently, on the risk of crashes and injuries. There is no national legislation regulating the number of hours or kilometres travelled by truck drivers. Consequently, it is almost impossible to define a standard number of hours or kilometres for truck drivers in a safety management system. This paper reviews the existing studies concerning safe system interventions such as tachographs in relation to fatigue caused by long working hours. This paper also reviews the literature to identify the influence of frequency of rest breaks on the reduction of work-related road transport accidents involving trucks. A framework is presented to manage truck drivers’ fatigue, which may result in the reduction of injuries and fatalities involving heavy vehicles.

Keywords: fatigue, time management, trucks, traffic safety

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Authors: George Mahalu

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The Chua diode has been configured over time in various ways, using electronic structures like operational amplifiers (AOs) or devices with gas or semiconductors. When discussing the use of semiconductor devices, tunnel diodes (Esaki diodes) are most often considered, and more recently, transistorized configurations such as lambda diodes. The paperwork proposed here uses in the modeling a lambda diode type configuration consisting of two junction field effect transistors (JFET). The original scheme is created in the MULTISIM electronic simulation environment and is analyzed in order to identify the conditions for the appearance of evolutionary unpredictability specific to nonlinear dynamic systems with chaos-induced behavior. The chaotic deterministic oscillator is one autonomous type, a fact that places it in the class of Chua’s type oscillators, the only significant and most important difference being the presence of a nonlinear device like the one mentioned structure above. The chaotic behavior is identified both by means of strange attractor-type trajectories and visible during the simulation and by highlighting the hypersensitivity of the system to small variations of one of the input parameters. The results obtained through simulation and the conclusions drawn are useful in the further research of ways to implement such constructive electronic solutions in theoretical and practical applications related to modern small signal amplification structures, to systems for encoding and decoding messages through various modern ways of communication, as well as new structures that can be imagined both in modern neural networks and in those for the physical implementation of some requirements imposed by current research with the aim of obtaining practically usable solutions in quantum computing and quantum computers.

Keywords: chua, diode, memristor, chaos

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Authors: Lonna Mabandla, Godfrey Musvoto

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Transportation is a catalytic feature in cities. Transport and land use activity are interdependent and have a feedback loop between how land is developed and how transportation systems are designed and used. This recursive relationship between land use and transportation is reflected in how public transportation routes internal to the inner-city enhance accessibility, therefore creating spaces that are conducive to business activity, while the business activity also informs public transportation routes. It is for this reason that the focus of this research is on public transportation within inner-city areas where the dynamic is evident. Durban is the chosen case study where the dominating form of public transportation within the central business district (CBD) is minibus taxis. The paradox here is that minibus taxis still form part of the informal economy even though they are the leading form of public transportation in South Africa. There have been many attempts to formalise this industry to follow more regulatory practices, but minibus taxis are privately owned, therefore complicating any proposed intervention. The argument of this study is that the application of collaborative planning through a sustainable partnership between the public and private sectors will improve the social and environmental sustainability of public transportation. One of the major challenges that exist within such collaborative endeavors is power dynamics. As a result, a key focus of the study is on power relations. Practically, power relations should be observed over an extended period, specifically when the different stakeholders engage with each other, to reflect valid data. However, a lengthy data collection process was not possible to observe during the data collection phase of this research. Instead, interviews were conducted focusing on existing procedural planning practices between the inner-city minibus taxi association (South and North Beach Taxi Association), the eThekwini Transport Authority (ETA), and the eThekwini Town Planning Department. Conclusions and recommendations were then generated based on these data.

Keywords: collaborative planning, sustainability, public transport, minibus taxis

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Authors: Jason West

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Low profitability in agriculture production along with increasing scrutiny over environmental effects is limiting food production at scale. In contrast, the mining sector offers access to resources including energy, water, transport and chemicals for food production at low marginal cost. Scalable agricultural production can benefit from the nexus of resources (water, energy, transport) offered by mining activity in remote locations. A decision support bioeconomic model for controlled environment vertical farms was used. Four submodels were used: crop structure, nutrient requirements, resource-crop integration, and economic. They escalate to a macro mathematical model. A demonstrable dynamic systems framework is needed to prove productive outcomes are feasible. We demonstrate a generalized bioeconomic macro model for controlled environment production systems in minesites using systems dynamics modeling methodology. Despite the complexity of bioeconomic modelling of resource-agricultural dynamic processes and interactions, the economic potential greater than general economic models would assume. Scalability of production as an input becomes a key success feature.

Keywords: crop production systems, mathematical model, mining, agriculture, dynamic systems

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Authors: Kasun P. Wijayaratna, Lauren Gardner, Taha Hossein Rashidi

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Undergraduate students entering university across the last 2 to 3 years tend to be born during the middle years of the 1990s. This generation of students has been exposed to the internet and the desire and dependency on technology since childhood. Brains develop based on environmental influences and technology has wired this generation of student to be attuned to sophisticated complex visual imagery, indicating visual forms of learning may be more effective than the traditional lecture or discussion formats. Furthermore, post-millennials perspectives on career are not focused solely on stability and income but are strongly driven by interest, entrepreneurship and innovation. Accordingly, it is important for educators to acknowledge the generational shift and tailor the delivery of learning material to meet the expectations of the students and the needs of industry. In the context of transport engineering, effectively teaching undergraduate students the basic principles of transport planning, traffic engineering and highway design is fundamental to the progression of the profession from a practice and research perspective. Recent developments in technology have transformed the discipline as practitioners and researchers move away from the traditional “pen and paper” approach to methods involving the use of computer programs and simulation. Further, enhanced accessibility of technology for students has changed the way they understand and learn material being delivered at tertiary education institutions. As a consequence, blended learning approaches, which aim to integrate face to face teaching with flexible self-paced learning resources, have become prevalent to provide scalable education that satisfies the expectations of students. This research study involved the development of a series of ‘Blended Learning’ initiatives implemented within an introductory transport planning and geometric design course, CVEN2401: Sustainable Transport and Highway Engineering, taught at the University of New South Wales, Australia. CVEN2401 was modified by conducting interactive polling exercises during lectures, including weekly online quizzes, offering a series of supplementary learning videos, and implementing a realistic design project that students needed to complete using modelling software that is widely used in practice. These activities and resources were aimed to improve the learning environment for a large class size in excess of 450 students and to ensure that practical industry valued skills were introduced. The case study compared the 2016 and 2017 student cohorts based on their performance across assessment tasks as well as their reception to the material revealed through student feedback surveys. The initiatives were well received with a number of students commenting on the ability to complete self-paced learning and an appreciation of the exposure to a realistic design project. From an educator’s perspective, blending the course made it feasible to interact and engage with students. Personalised learning opportunities were made available whilst delivering a considerable volume of complex content essential for all undergraduate Civil and Environmental Engineering students. Overall, this case study highlights the value of blended learning initiatives, especially in the context of large class size university courses.

Keywords: blended learning, highway design, teaching, transport planning

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Authors: Soma Chatterjee, I. Das

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In the present study, we have investigated the structural, electrical and magneto-transport properties of polycrystalline and nanocrystalline Gd0.5Sr0.5MnO3 compounds. The variation of transport properties is modified by tuning the grain size of the material. In the high-temperature semiconducting region, temperature-dependent resistivity data can be well explained by the non-adiabatic small polaron hopping (SPH) mechanism. In addition, the resistivity data for all compounds in the low-temperature paramagnetic region can also be well explained by the variable range hopping (VRH) model. The parameters obtained from SPH and VRH mechanisms are found to be reasonable. In the case of nanocrystalline compounds, there is an overlapping temperature range where both SPH and VRH models are valid simultaneously, and a new conduction mechanism - variable range hopping of small polaron s(VR-SPH) is satisfactorily valid for the whole temperature range of these compounds. However, for the polycrystalline compound, the overlapping temperature region between VRH and SPH models does not exist and the VR-SPH mechanism is not valid here. Thus, polarons play a leading role in selecting different conduction mechanisms in different temperature ranges.

Keywords: electrical resistivity, manganite, small polaron hopping, variable range hopping, variable range of small polaron hopping

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Authors: T. Wejrzanowski, M. Grybczuk, E. Tymicki, K. J. Kurzydlowski

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In the present study numerical simulations silicon carbide single crystal growth process in Physical Vapor Transport reactor are addressed. Silicon Carbide is a perspective material for many applications in modern electronics. One of the main challenges for wider applications of SiC is high price of high quality mono crystals. Improvement of silicon carbide manufacturing process has a significant influence on the product price. Better understanding of crystal growth allows for optimization of the process, and it can be achieved by numerical simulations. In this work Virtual Reactor software was used to simulate the process. Predicted geometrical properties of the final product and information about phenomena occurring inside process reactor were obtained. The latter is especially valuable because reactor chamber is inaccessible during the process due to high temperature inside the reactor (over 2000˚C). Obtained data was used for improvement of the process and reactor geometry. Resultant crystal quality was also predicted basing on crystallization front shape evolution and threading dislocation paths. Obtained results were confronted with experimental data and the results are in good agreement.

Keywords: Finite Volume Method, semiconductors, Physical Vapor Transport, silicon carbide

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Authors: Juanita, B. Kombaitan, Iwan Pratoyo Kusumantoro

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The traditional mode is a non-motorized vehicle powered by human or animal power. The objective of the study was to define the strategy of using traditional modes by the framework of sustainable urban transport in support of urban tourism activities. The study of the traditional mode does not include a modified mode using the engine power as motor tricycles are often called ‘bentor ‘in Indonesia. The use of non-motorized traditional mode in Indonesia has begun to shift, and its use began to be eliminated by the change of propulsion using the machine. In an effort to push back the use of traditional mode one of them with tourism activities. Strategies for the use of traditional modes within the framework of sustainable urban transport are seen from three dimensions: social, economic and environmental. The social dimension related to accessibility and livability, an economic dimension related to traditional modes can promote products and tourist attractions, while the environmental dimension related to the needs of the users/groups with respect to safety, comfort. The traditional mode is rarely noticed by the policy makers, and public opinion in its use needs attention. The involvement of policy-making between stakeholders and the community is needed in the development of sustainable traditional mode strategies in support of urban tourism activities.

Keywords: traditional mode, sustainable, urban, transportation

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Authors: Triem T. Hoang

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Loop heat pipes (LHPs) are two-phase capillary-pumped heat transports. An appropriate working fluid is selected for the intended application temperature range. A closed-loop is evacuated to a high vacuum, back-filled partially with the working fluid, and then hermetically sealed under the fluid own pressure. Heat from a heat source conducts through the evaporator casing to vaporize liquid on the outer surface of the wick structure inside the evaporator. The generated vapor is compelled to vent out of the evaporator and into the vapor line for transport to the condenser assembly. There, heat is removed and rejected to a heat sink to condensed vapor back to liquid. The liquid exits the condenser and travels in the liquid line to return to the evaporator to complete the cycle. The circulation of fluid, and thus the heat transport in the LHP, is accomplished entirely by capillary action. The LHP contains no mechanical moving part to wear out or break down and, therefore possesses, reliability and a long life even without maintenance. In this paper, the author not only attempts to introduce the LHP technology in simplistic terms to those who are not familiar with it but also provides necessary technical information to potential users for the proper design and analysis of the LHP system.

Keywords: two-phase heat transfer, loop heat pipe, capillary pumped technology, thermal-fluid modeling

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Authors: Jaqueline Nichi, Leila Da Costa Ferreira, Fabiana Barbi Seleguim, Gabriela Marques Di Giulio, Mariana Barbieri

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The transport sector is responsible for approximately 55% of global greenhouse gas (GHG) emissions, in addition to pollution and other negative externalities, such as road accidents and congestion, that impact the routine of those who live in large cities. The objective of this article is to discuss the application and use of distinct mobility technologies such as climate adaptation and mitigation measures in the context of smart cities in the Global South. The documentary analysis is associated with 22 semi structured interviews with managers who work with mobility technologies in the public and private sectors and in civil society organizations to explore solutions in multilevel governance for smart and low-carbon mobility based on the case study from the city of São Paulo, Brazil. The hypothesis that innovation and technology to mitigate and adapt to climate impacts are not yet sufficient to make mobility more sustainable has been confirmed. The results indicate four relevant aspects for advancing a climate agenda in smart cities: integrated planning, coproduction of knowledge, experiments in governance, and new means of financing to guarantee the sustainable sociotechnical transition of the sector.

Keywords: urban mobility, climate change, smart cities, multilevel governance

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Authors: Yanan Zhu

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Based on the previous work about the influence mechanism of the mobility difference of phenyl and thienyl substituent semiconductors, we have made further exploration towards to design high-performance organic thin-film transistors. The substituent groups effect plays a significant role in materials properties and device performance as well. For the theoretical study, simulation of materials property and crystal packing can supply scientific guidance for materials synthesis in experiments. This time, we have taken the computational methods to design a new material substituent with furan groups, which are the potential to be used in organic thin-film transistors and organic single-crystal transistors. The reorganization energy has been calculated and much lower than 2,6-diphenyl anthracene (DPAnt), which performs large mobility as more than 30 cm²V⁻¹s⁻¹. Moreover, the other important parameter, charge transfer integral is larger than DPAnt, which suggested the furan substituent material may get a much better charge transport data. On the whole, the mechanism investigation based on phenyl and thienyl assisted in designing novel materials with furan substituent, which is predicted to be an outperformed organic field-effect transistors.

Keywords: theoretical calculation, mechanism, mobility, organic transistors

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Authors: Trieu Anh Ngoc, Nguyen Quang Kim

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Located at the downstream of the Mekong Delta, the Vietnamese Mekong Delta is well-known as 'rice bowl' of Vietnam. The Vietnamese Mekong Delta experiences widespread flooding annually where is habitat for about 17 million people. The economy of this region mainly depends on the agricultural productivities. The suspended sediment load in the Mekong River plays an important role in carrying contaminants and nutrients to the delta and changing the geomorphology of the delta river system. In many past decades, flooding and suspended sediment were considered as indispensable factors in agricultural cultivations. Although flooding in the wet season caused serious inundation in paddy field and affected livelihoods, it is an effective facility for flushing acid and saline to this area - alluvial soil heavily contaminated with acid and salt intrusion. In addition, sediment delivery to this delta contained rich-nutrients distributed and deposited on the fields through flooding process. In recent decades, the changing of flow and sediment transport have been strongly and clearly occurring due to upstream dam development and climate change. However, effects of sediment delivery on agricultural cultivations were less attention. This study investigated the impacts of upstream flow on sediment distribution in the Vietnamese Mekong Delta. Flow fluctuation and sediment distribution were simulated by the Mike 11 model, including hydrodynamics model and advection-dispersion model. Various scenarios were simulated based on anticipated upstream discharges. Our findings indicated that sediment delivery into the Vietnamese Mekong Delta come from not only Tien River but also border of Cambodia floodplains. Sediment distribution in the Vietnamese Mekong Delta is dramatically changed by the distance from the main rivers and the secondary channels. The dam development in the upstream is one of the major factors leading a decrease in sediment discharge as well as sediment deposition. Moreover, sea level rise partially contributed to decrease in sediment transport and change of sediment distribution between upstream and downstream of the Vietnamese Mekong Delta.

Keywords: sediment transport, sea level rise, climate change, Mike Model

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Authors: Hassan Taimoor, Piotr Krajewski, Piotr Gabrielzcak

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Being responsible for the largest source of energy-related emissions, the transportation sector is driven by more than half of global oil demand and total energy consumption, making it a crucial factor in tackling climate change and environmental degradation. The present study empirically tests the effectives of the energy-related tax (TXEN) in curbing transport-related carbon emissions (CO2TRANSP) in Organization for Economic Cooperation and Development (OECD) economies over the period of 1990-2020. Moreover, Green Finance (GF), Technology (TECH), and Gross domestic product (GDP) have also been added as explanatory factors which might affect CO2TRANSP emissions. The study employs the Method of Moment Quantile Regression (MMQR), an advance econometric technique to observe the variations along each quantile. Based on the results of the preliminary test, we confirm the presence of cross-sectional dependence and slope heterogeneity. Whereas the result of the panel unit root test report mixed order of variables’ integration. The findings reveal that rise in income level activates CO2TRANSP, confirming the first stage of Environmental Kuznet Hypothesis. Surprisingly, the present TXEN policies of OECD member states are not mature enough to tackle the CO2TRANSP emissions. However, the findings confirm that GF and TECH are solely responsible for the reduction in the CO2TRANSP. The outcomes of Bootstrap Quantile Regression (BSQR) further validate and support the earlier findings of MMQR. Based on the findings of this study, it is revealed that the current TXEN policies are too moderate, and an incremental and progressive rise in TXEN may help in a transition toward a cleaner and sustainable transportation sector in the study region.

Keywords: transport-related CO2 emissions, energy-related tax, green finance, technological development, oecd member states

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Authors: Sharif Muddsair, Eisels Martin, Giesbrecht Eugenie

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With development of society increase the demand for the movement of people also increases gradually. The various modes of the transport in different extent which expat impacts, which depends on mainly technical-operating conditions. The up-to-date telematics systems provide the transport industry a revolutionary. Appropriate use of these systems can help to substantially improve the efficiency. Vehicle monitoring and fleet tracking are among services used for improving efficiency and effectiveness of utility vehicle. There are many telematics systems which may contribute to eco-driving. Generally, they can be grouped according to their role in driving cycle. • Before driving - eco-route selection, • While driving – Advanced driver assistance, • After driving – remote analysis. Our point of interest is regulated in third point [after driving – remote analysis]. TS [Telematics-system] make it possible to record driving patterns in real time and analysis the data later on, So that driver- classification-specific hints [fast driver, slow driver, aggressive driver…)] are given to imitate eco-friendly driving style. Together with growing number of vehicle and development of information technology, telematics become an ‘active’ research subject in IT and the car industry. Telematics has gone a long way from providing navigation solution/assisting the driver to become an integral part of the vehicle. Today’s telematics ensure safety, comfort and become convenience of the driver.

Keywords: internet of things, iot, connected vehicle, cv, ts, telematics services, ml, machine learning

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Authors: Aidan N. Smallwood, Celestine R. Weegenaar, Jack N. Evans

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The intensive care unit (ICU) is a particularly resource heavy environment, in terms of staff, drugs and equipment required. Whilst many areas of the hospital are attempting to cut down on plastic use and minimise their impact on the environment, this has proven challenging within the confines of intensive care. Concurrently, as globalization has progressed over recent decades, there has been a tendency towards centralised manufacturing with international distribution networks for products, often covering large distances. In this study, we have modelled the standard consumption of plastic single-use items over the course of the first 24-hours of an average individual patient’s stay in a 12 bed ICU in the United Kingdom (UK). We have identified the country of manufacture and calculated the minimum possible distance travelled by each item from factory to patient. We have assumed direct transport via the shortest possible straight line from country of origin to the UK and have not accounted for transport within either country. Assuming an intubated patient with invasive haemodynamic monitoring and central venous access, there are a total of 52 distincts, largely plastic, disposable products which would reasonably be required in the first 24-hours after admission. Each product type has only been counted once to account for multiple items being shipped as one package. Travel distances from origin were summed to give the total distance combined for all 52 products. The minimum possible total distance travelled from country of origin to the UK for all types of product was 273,353 km, equivalent to 6.82 circumnavigations of the globe, or 71% of the way to the moon. The mean distance travelled was 5,256 km, approximately the distance from London to Mecca. With individual packaging for each item, the total weight of consumed products was 4.121 kg. The CO2 produced shipping these items by air freight would equate to 30.1 kg, however doing the same by sea would produce 0.2 kg CO2. Extrapolating these results to the 211,932 UK annual ICU admissions (2018-2019), even with the underestimates of distance and weight of our assumptions, air freight would account for 6586 tons CO2 emitted annually, approximately 130 times that of sea freight. Given the drive towards cost saving within the UK health service, and the decline of the local manufacturing industry, buying from intercontinental manufacturers is inevitable However, transporting all consumables by sea where feasible would be environmentally beneficial, as well as being less costly than air freight. At present, the NHS supply chain purchases from medical device companies, and there is no freely available information as to the transport mode used to deliver the product to the UK. This must be made available to purchasers in order to give a fuller picture of life cycle impact and allow for informed decision making in this regard.

Keywords: CO2, intensive care, plastic, transport

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Authors: Santosh Kumar Biswal, Ramakar Jha

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Soil erosion is a slow and continuous process and one of the prominent problems across the world leading to many serious problems like loss of soil fertility, loss of soil structure, poor internal drainage, sedimentation deposits etc. In this paper remote sensing and GIS based methods have been applied for the determination of soil erosion and sediment yield. Tel River basin which is the second largest tributary of the river Mahanadi laying between latitude 19° 15' 32.4"N and, 20° 45' 0"N and longitude 82° 3' 36"E and 84° 18' 18"E chosen for the present study. The catchment was discretized into approximately homogeneous sub-areas (grid cells) to overcome the catchment heterogeneity. The gross soil erosion in each cell was computed using Universal Soil Loss Equation (USLE). Various parameters for USLE was determined as a function of land topography, soil texture, land use/land cover, rainfall, erosivity and crop management and practice in the watershed. The concept of transport limited accumulation was formulated and the transport capacity maps were generated. The gross soil erosion was routed to the catchment outlet. This study can help in recognizing critical erosion prone areas of the study basin so that suitable control measures can be implemented.

Keywords: Universal Soil Loss Equation (USLE), GIS, land use, sediment yield,

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Authors: Sascha E. Oswald, Jan Busch

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The in-situ dechlorination of contamination by chlorinated solvents in groundwater via zero-valent iron (nZVI) is potentially an efficient and prompt remediation method. A key requirement is that nZVI has to be introduced in the subsurface in a way that substantial quantities of the contaminants are actually brought into direct contact with the nZVI in the aquifer. Thus it could be a more flexible and precise alternative to permeable reactive barrier techniques using granular iron. However, nZVI are often limited by fast agglomeration and sedimentation in colloidal suspensions, even more so in the aquifer sediments, which is a handicap for the application to treat source zones or contaminant plumes. Colloid-supported nZVI show promising characteristics to overcome these limitations and Carbo-Iron Colloids is a newly developed composite material aiming for that. The nZVI is built onto finely ground activated carbon of about a micrometer diameter acting as a carrier for it. The Carbo-Iron Colloids are often suspended with a polyanionic stabilizer, and carboxymethyl cellulose is one with good properties for that. We have investigated the transport behavior of Carbo-Iron Colloids (CIC) on different scales and for different conditions to assess its mobility in aquifer sediments as a key property for making its application feasible. The transport properties were tested in one-dimensional laboratory columns, a two-dimensional model aquifer and also an injection experiment in the field. Those experiments were accompanied by non-invasive tomographic investigations of the transport and filtration processes of CIC suspensions. The laboratory experiments showed that a larger part of the CIC can travel at least scales of meters for favorable but realistic conditions. Partly this is even similar to a dissolved tracer. For less favorable conditions this can be much smaller and in all cases a particular fraction of the CIC injected is retained mainly shortly after entering the porous medium. As field experiment a horizontal flow field was established, between two wells with a distance of 5 meters, in a confined, shallow aquifer at a contaminated site in North German lowlands. First a tracer test was performed and a basic model was set up to define the design of the CIC injection experiment. Then CIC suspension was introduced into the aquifer at the injection well while the second well was pumped and samples taken there to observe the breakthrough of CIC. This was based on direct visual inspection and total particle and iron concentrations of water samples analyzed in the laboratory later. It could be concluded that at least 12% of the CIC amount injected reached the extraction well in due course, some of it traveling distances larger than 10 meters in the non-uniform dipole flow field. This demonstrated that these CIC particles have a substantial mobility for reaching larger volumes of a contaminated aquifer and for interacting there by their reactivity with dissolved contaminants in the pore space. Therefore they seem suited well for groundwater remediation by in-situ formation of reactive barriers for chlorinated solvent plumes or even source removal.

Keywords: carbo-iron colloids, chlorinated solvents, in-situ remediation, particle transport, plume treatment

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Authors: Atcharawan Phenwansuk

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The product design is important to the development of SME towards the global, because it made to the quality product to react the needs of consumers and could reduces cost in the production, making it more profitable. As a results, the business are competition advantage for more marketing. It also enhance image of product and firms to build its own brand products to be acceptable. The product was designed should be shape, size, colorful, and direct of target consumers. This is method to add value products to get popular and effective, because the beauty is first satisfaction which come from main shape and color of the design product, but the product was designed need to hold data and law combination of shape and color between artistic theory and satisfaction of consumers together. The design must consider the safety of life and asset of consumers the most important. From to use of designed products should be to consider the cost savings, convenient distance, transportation, routes (land, water or air) of living space on transport (capacity, volume, width, length of the car, truck and container, etc). The packaging must be can to prevent not damage of the products. If products is more large , maybe to design new packaging, which can easily disassembled for make smaller package such as designing the assembly. Products must be packed in the container for size standard for save costs, as well as the buyer can make transport and assembly of products to fit easily on your own.

Keywords: logistics process , pineapple’s leaves product, product design, satisfaction of consumers

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Authors: Martin Gascón Hove, Ralph Vermeltfoort, Alessandro Fiorini, Erwan Dulaurent, Henning von Perbandt

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Introduction: The outbreak of the COVID-19 pandemic has completely changed the global health situation, with more than 400 million cases published and over 5 million deaths. European Air Transport Command (EATC) is integrated by seven nations, and among its capabilities is that of aeromedical evacuation (AM). Material and methods: Impact of novel coronavirus was analysed based on the number and characteristics of patients and executed missions within EATC and, particularly by Spain, during the biennium 2020-2021. Results: One thousand sixty patients were transported in 186 missions. Neither death nor disease contagion was reported during AM performances. Military cases transferred were 986, mostly routine priority (91,4%), and 74 were civilians, who were transported in 17 missions, and 81,1% of which were categorized as urgent. Niger led the list of original countries, with 191 evacuated patients. 76,1% of requests came from Italy and Germany. Airbus A310 was the most used aircraft (32,2%). Germany transported 222 patients of another nationality, while Spain executed eight missions and repatriated 68 cases, 58 of which were from Mali. Conclusions: COVID-19 has led to a surged number of evacuated patients inside EATC, which has proven to be a safe and effective means of transportation, even in critical cases. Spain has gained prominence since its annexation in 2015.

Keywords: COVID-19, SARS-CoV-2, pandemic, aviation, Spain

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Authors: George Mahalu

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The Chua diode has been configured over time in various ways, using electronic structures like as operational amplifiers (OAs) or devices with gas or semiconductors. When discussing the use of semiconductor devices, tunnel diodes (Esaki diodes) are most often considered, and more recently, transistorized configurations such as lambda diodes. The paper-work proposed here uses in the modeling a lambda diode type configuration consisting of two Junction Field Effect Transistors (JFET). The original scheme is created in the MULTISIM electronic simulation environment and is analyzed in order to identify the conditions for the appearance of evolutionary unpredictability specific to nonlinear dynamic systems with chaos-induced behavior. The chaotic deterministic oscillator is one autonomous type, a fact that places it in the class of Chua’s type oscillators, the only significant and most important difference being the presence of a nonlinear device like the one mentioned structure above. The chaotic behavior is identified both by means of strange attractor-type trajectories and visible during the simulation and by highlighting the hypersensitivity of the system to small variations of one of the input parameters. The results obtained through simulation and the conclusions drawn are useful in the further research of ways to implement such constructive electronic solutions in theoretical and practical applications related to modern small signal amplification structures, to systems for encoding and decoding messages through various modern ways of communication, as well as new structures that can be imagined both in modern neural networks and in those for the physical implementation of some requirements imposed by current research with the aim of obtaining practically usable solutions in quantum computing and quantum computers.

Keywords: chaos, lambda diode, strange attractor, nonlinear system

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Authors: L. Kolatorova, J. Vitku, K. Adamcova, M. Simkova, M. Hill, A. Parizek, M. Duskova

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Endocrine disruptors (EDs) are substances leaching from various industrial products, which are able to interfere with the endocrine system. Their harmful effects on human health are generally well-known, and exposure during fetal development may have lasting effects. Fetal exposure and transplacental transport of bisphenol A (BPA) have been recently studied; however, less is known about alternatives such as bisphenol S (BPS), bisphenol F (BPF) and bisphenol AF (BPAF), which have started to appear in consumer products. The human organism is usually exposed to the mixture of EDs, out of which parabens are otherwise known to transfer placenta. The usage of many cosmetic, pharmaceutical and consumer products during the pregnancy that may contain parabens and bisphenols has led to the need for investigation. The aim of the study was to investigate the transplacental transport of BPA, its alternatives, and parabens, and to study their relation to fetal steroidogenesis. BPA, BPS, BPF, BPAF, methylparaben, ethylparaben, propylparaben, butylparaben, benzylparaben and 15 steroids including estrogens, corticoids, androgens and immunomodulatory ones were determined in 27 maternal (37th week of gestation) and cord plasma samples using liquid chromatography - tandem mass spectrometry methods. The statistical evaluation of the results showed significantly higher levels of BPA (p=0.0455) in cord plasma compared to maternal plasma. The results from multiple regression models investigated that in cord plasma, methylparaben, propylparaben and the sum of all measured parabens were inversely associated with testosterone levels. To our best knowledge, this study is the first attempt to determine the levels of alternative bisphenols in the maternal and cord blood, and also the first study reporting the simultaneous detection of bisphenols, parabens, and steroids in these biological fluids. Our study confirmed the transplacental transport of BPA, with likely accumulation in the fetal compartment. The negative association of cord blood parabens and testosterone levels highlights their possible risks, especially for the development of male fetuses. Acknowledgements: This work was supported by the project MH CR 17-30528 A from the Czech Health Research Council, MH CZ - DRO (Institute of Endocrinology - EÚ, 00023761) and by the MEYS CR (OP RDE, Excellent research - ENDO.CZ).

Keywords: bisphenol, endocrine disruptor, paraben, pregnancy, steroid

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Authors: Xuguo Zhang, Jimmy Fung, Kenneth Leung, Alexis Lau

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Fine particulate matter concentrations have been decreasing in the past few years while the ozone concentrations are posing an increasing trend in the Greater Bay Area (GBA) of China. A series of control policies have been released to mitigate the country-wide air pollution, however, how to effectively evaluate the exercised control measures and efficiently reveal potential projected mitigation pathways are still limited. By refining an enhanced air-quality-modeling system, this study provides an account of the air quality assessments from 2019 to 2025 to appraise the air quality results and improvement under designed scenarios for assessing the optimum scope for tightening the Air Quality Objectives (AQOs). The results show that it is doable to tighten the 24-hour AQO for SO2 from the World Health Objective air quality guidelines Interim Targets Level-1 (IT-1) (125μg/m3) to IT-2 level (50μg/m3) with the current number of exceedance allowed (three) remains unchanged. It is also possible to tighten the annual AQO for PM2.5 from IT-1 (35 μg/m3) to IT 2 (25 μg/m3), and its 24-hr AQO from IT-1 (75 μg/m3) to IT 2 (50 μg/m3) with the number of exceedances allowed increased from current nine to 35. Regional cooperation under the development of the GBA cooperation are still needed to be focused and strengthen due to the cross-boundary transport characteristics of the air pollution.

Keywords: air quality attainment, Hong Kong, mitigation policy, chemical transport modeling, sensitivity analysis

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Authors: Morteza Hamidpour, Kambeez Shahroudi

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The aim of this research was to identify the factors affecting the measurement and management of marketing performance in Iran's airports and air navigation companies (Economics in Air and Airport Transport). This study was exploratory and used a qualitative content analysis technique. The study population consisted of university professors in the field of air transportation and senior airport managers, with 15 individuals selected as samples using snowball technique. Based on the results, 15 main indicators were identified for measuring the marketing performance of Iran's airports and air navigation companies. These indicators include airport staff, general and operational expenses, annual passenger reception capacity, number of counter receptions and passenger dispatches, airport runway length, airline companies' loyalty to using airport space and facilities, regional market share of transit and departure flights, claims and net profit (aviation and non-aviation). By keeping the input indicators constant, the output indicators can be improved, enhancing performance efficiency and consequently increasing the economic situation in air transportation.

Keywords: air transport economics, marketing performance management, marketing performance input factors, marketing performance intermediary factors, marketing performance output factors, content analysis

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