Search results for: cooling of matter

Authors: Armando Cartenì

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Within the design of sustainable transportation engineering, the problem of reducing particulate matter (PM) concentrations in railways metro system was not much discussed. It is well known that PM levels in railways metro system are mainly produced by mechanical friction at the rail-wheel-brake interactions and by the PM re-suspension caused by the turbulence generated by the train passage, which causes dangerous problems for passenger health. Starting from these considerations, the aim of this research was twofold: i) to investigate the particulate matter concentrations in a ‘traditional’ railways metro system; ii) to investigate the particulate matter concentrations of a ‘high quality’ metro system equipped with design devices useful for reducing PM concentrations: platform screen doors, rubber-tyred and an advanced ventilation system. Two measurement surveys were performed: one in the ‘traditional’ metro system of Naples (Italy) and onother in the ‘high quality’ rubber-tyred metro system of Turin (Italy). Experimental results regarding the ‘traditional’ metro system of Naples, show that the average PM10 concentrations measured in the underground station platforms are very high and range between 172 and 262 µg/m3 whilst the average PM2,5 concentrations range between 45 and 60 µg/m3, with dangerous problems for passenger health. By contrast the measurements results regarding the ‘high quality’ metro system of Turin show that: i) the average PM10 (PM2.5) concentrations measured in the underground station platform is 22.7 µg/m3 (16.0 µg/m3) with a standard deviation of 9.6 µg/m3 (7.6 µg/m3); ii) the indoor concentrations (both for PM10 and for PM2.5) are statistically lower from those measured in outdoors (with a ratio equal to 0.9-0.8), meaning that the indoor air quality is greater than those in urban ambient; iii) that PM concentrations in underground stations are correlated to the trains passage; iv) the inside trains concentrations (both for PM10 and for PM2.5) are statistically lower from those measured at station platform (with a ratio equal to 0.7-0.8), meaning that inside trains the use of air conditioning system could promote a greater circulation that clean the air. The comparison among the two case studies allow to conclude that the metro system designed with PM reduction devices allow to reduce PM concentration up to 11 times against a ‘traditional’ one. From these results, it is possible to conclude that PM concentrations measured in a ‘high quality’ metro system are significantly lower than the ones measured in a ‘traditional’ railway metro systems. This result allows possessing the bases for the design of useful devices for retrofitting metro systems all around the world.

Keywords: air quality, pollutant emission, quality in public transport, underground railway, external cost reduction, transportation planning

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Authors: Emrah Yaliniz, Ali Kalkanli

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ZE41A magnesium alloy has been extensively used in aerospace industry, especially for use in rotorcraft transmission casings. Due to the improved mechanical properties, the latest generation of magnesium casting alloy EV31A-T6 (Elektron 21® specified in AMS 4429) is seen as a potential replacement for ZE41A in terms of strength. Therefore, the necessity of enhancement has been arisen for ZE41A in order to avoid fully replacement. The main element affecting the strength of ZE41A is Zirconium (Zr), which acts as a grain refiner. The specified range of Zr element for ZE41A alloy is between 0.4 wt % and 1.0 wt % (unless otherwise stated by weight percentage after this point) as stated in AMS 4439. This paper investigates the effects of Zr amount on tensile and metallurgical properties of ZE41A magnesium alloy. The Zr alloying amount for the research has been chosen as 0.5 % and 1 %, which are standard amounts in a commercial alloy (average of 0.4-0.6%) and maximum percent in the standard, separately. 1 % Zr amount has been achieved via Zirmax (66.7 Mg-33.3 Zr) master alloy addition. The ultimate tensile strength of ZE41A with 1% Zr has been increased up to about 220-225 MPa in comparison to 200 MPa given in AMS 4439. The reason for the increase in strength with the addition of Zirmax is based on the decrease in grain size, which was measured about 30 µm. Optical microscope, scanning electron microscopy (SEM) and X-ray Diffraction (XRD) were used to detect the change in the microstructural futures via alloying. The zirconium rich coring at the center of the grains was observed in addition to the grain boundary intermetallic phases and bulk Mg-rich matrix. The solidification characteristics were also identified by using the cooling curve obtained from the sand casting mold during cooling of the alloys.

Keywords: aerospace, grain refinement, magnesium, sand casting, ZE41A

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Authors: Erinetta P. Anjani, Karina Mariz, Rifqi K. Fathianto

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While Islam teaches its’ followers to be mindful of God’s creation, including the environment, Indonesia as one of the world’s largest Muslim country, is now also world’s second-largest plastic waste contributor. The problem of waste is a complicated matter in Indonesia and is worsening because many landfills are now on verge of overcapacity. The causes of this problem are at least due to two things. First is Indonesia’s bad waste management. Second, people’s low of eco-literacy, as can be seen in massive use of non-degradable materials, low rate of waste separation, low rate of recycling and up cycling, whereas households are the largest source of waste in Indonesia. Mostly dealing with patriarchal culture, women in Indonesia play big and important role in their households, from family matter to household management (including waste management), to economic matter. Uniquely, the majority of Muslim women in Indonesia are engaged in -arisan- women social gathering or in -majelis ta’lim- women community in Islamic prayer, which serves as a social mechanism. As many NGOs are working on tackling environmental issues by raising awareness in order for the people to adapt a more environmentally-friendly household management practices, the problem of waste in Indonesia is meeting a bright light. Using qualitative data and descriptive analysis, the following is a proposal for a program intended to spread eco-literacy for waste management to women in Indonesia through their social gathering in order for them to gain awareness and start implementing eco-actions in their households. We attempt Waste4Change, a social company which provides environmentally-friendly waste management services, to reach women with modules that consist of environmental education, trainings, and workshops. We will then monitor and counsel the women to make sure if the lesson is going to be fully applied in their houses. The program will take place nearby University of Indonesia, Depok, West Java.

Keywords: eco-literacy, environmental education, household waste management, Muslim women social gathering, Waste4Change

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Authors: Yang Xiao-Jun, Yu Tian-Hao, Hu Ying-Qi

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Breathing in foreign objects during the operation of the aircraft engine, impurities in the aircraft fuel and products of incomplete combustion can produce deposits on the surface of the turbine blades. These deposits reduce not only the turbine's operating efficiency but also the life of the turbine blades. Based on the small open wind tunnel, the simulation of deposits on the leading edge of the turbine has been carried out in this work. The effect of film cooling on particulate deposition was investigated. Based on the analysis, the adhesive mechanism for the molten pollutants’ reaching to the turbine surface was simulated by matching the Stokes number, TSP (a dimensionless number characterizing particle phase transition) and Biot number of the test facility and that of the real engine. The thickness distribution and growth trend of the deposits have been observed by high power microscope and infrared camera under different temperature of the main flow, the solidification temperature of the particulate objects, and the blowing ratio. The experimental results from the leading edge particulate deposition demonstrate that the thickness of the deposition increases with time until a quasi-stable thickness is reached, showing a striking effect of the blowing ratio on the deposition. Under different blowing ratios, there exists a large difference in the thickness distribution of the deposition, and the deposition is minimal at the specific blow ratio. In addition, the temperature of main flow and the solidification temperature of the particulate have a great influence on the deposition.

Keywords: deposition, experiment, film cooling, leading edge, paraffin particles

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Authors: Luiz Carlos Wrobel, Matjaz Hribersek, Jure Marn, Jurij Iljaz

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Dynamic thermography has been clinically proven to be a valuable diagnostic technique for skin tumor detection as well as for other medical applications such as breast cancer diagnostics, diagnostics of vascular diseases, fever screening, dermatological and other applications. Thermography for medical screening can be done in two different ways, observing the temperature response under steady-state conditions (passive or static thermography), and by inducing thermal stresses by cooling or heating the observed tissue and measuring the thermal response during the recovery phase (active or dynamic thermography). The numerical modelling of heat transfer phenomena in biological tissue during dynamic thermography can aid the technique by improving process parameters or by estimating unknown tissue parameters based on measured data. This paper presents a nonlinear numerical model of multilayer skin tissue containing a skin tumor, together with the thermoregulation response of the tissue during the cooling-rewarming processes of dynamic thermography. The model is based on the Pennes bioheat equation and solved numerically by using a subdomain boundary element method which treats the problem as axisymmetric. The paper includes computational tests and numerical results for Clark II and Clark IV tumors, comparing the models using constant and temperature-dependent thermophysical properties, which showed noticeable differences and highlighted the importance of using a local thermoregulation model.

Keywords: boundary element method, dynamic thermography, static thermography, skin tumor diagnostic

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Authors: Ernesto A. Lagarda-Leyva, Manuel A. Valenzuela L., José G. Oshima C., Arnulfo A. Naranjo-Flores

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From August to December of 2016, a diagnostic and strategic planning study was carried out on the supply chain of the company Agropecuaria GABO S.A. de C.V. The final product of the study was the development of the strategic plan and a project portfolio to meet the demands of the three links in the supply chain of the Roma tomato exported annually to the United States of America. In this project, the strategic objective of ensuring the proper handling of the product was selected and one of the goals associated with this was the employment of quantitative methods to support decision making. Considering the antecedents, the objective of this case study was to develop a model to analyze the behavioral dynamics in the distribution chain, from the logistics of storage and shipment of Roma tomato in 81-case pallets (11.5 kg per case), to the two pre-cooling rooms and eventual loading onto transports, seeking to reduce the bottleneck and the associated costs by means of a dynamic interface. The methodology used was that of system dynamics, considering four phases that were adapted to the purpose of the study: 1) the conceptualization phase; 2) the formulation phase; 3) the evaluation phase; and 4) the communication phase. The main practical conclusions lead to the possibility of reducing both the bottlenecks in the cooling rooms and the costs by simulating scenarios and modifying certain policies. Furthermore, the creation of the dynamic interface between the model and the stakeholders was achieved by generating interaction with buttons and simple instructions that allow making modifications and observing diverse behaviors.

Keywords: agrilogistics, distribution, scenarios, system dynamics

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Authors: Esmaeil Asadzadeh, Mehtab Alam

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Well documented records of the past failures of the structures reveals that the progressive collapse of structures is one of the major reasons for dramatic human loss and economical consequences. Progressive collapse is the failure mechanism in which the structure fails gradually due to the sudden removal of the structural elements. The sudden removal of some structural elements results in the excessive redistributed loads on the others. This sudden removal may be caused by any sudden loading resulted from local explosion, impact loading and terrorist attacks. Hyperbolic thin walled concrete shell structures being an important part of nuclear and thermal power plants are always prone to such terrorist attacks. In concrete structures, the gradual failure would take place by generation of initial cracks and its propagation in the supporting columns along with the tower shell leading to the collapse of the entire structure. In this study the mechanism of progressive collapse for such high raised towers would be simulated employing the finite element method. The aim of this study would be providing clear conceptual step-by-step descriptions of various procedures for progressive collapse analysis using commercially available finite element structural analysis software’s, with the aim that the explanations would be clear enough that they will be readily understandable and will be used by practicing engineers. The study would be carried out in the following procedures: 1. Provide explanations of modeling, simulation and analysis procedures including input screen snapshots; 2. Interpretation of the results and discussions; 3. Conclusions and recommendations.

Keywords: progressive collapse, cooling towers, finite element analysis, crack generation, reinforced concrete

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Authors: Mardiati Zain, Elihasridas, Yolani Utami, Bima Bagaskara, Muhammad Taufic

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The purpose of this study is to formulated a ration that can increased concentration of bioactive compounds in the form of conjugated linoleic acid (CLA) and polyunsaturated fatty acids acid (PUFA) in milk to produce functional milk that is beneficial for health. It has been proven that forage-based feeds (grass and legumes) are able to increased the presence of polyunsaturated fatty acids and in particular conjugated linoleic acid CLA in milk. Presence of bioactive compounds in product fat of ruminant origin these have generated great interest because they are associated with their potential as anti carcinogenic, anti diabetogenic and stimulant of the immune response. PUFA and CLA and especially n-3 fatty acids, only 4% of the fatty acids present in milk. For that, efforts need to be made to change the fatty acid composition of milk to increase the nutritional value for consumers through increasing the concentration of PUFA and CLA This is very important in the midst of the covid pandemic 19 which is increasing, it is necessary to drink and food that can improve the system body immunity. . The study was conducted in vivo using a randomized block design with 4 treatments and 4 replications. This experiment used 16 heads of 40-55 kg lactating goats. Goat were fed a basal diet containing (dry matter basis) 60% native grass and 40% concentrate. The treatment was A. 60% native grass + 40% concentrate, B. 60% native grass + 30% concentrate + 10% I. zollengeriana C. 60% native grass + 20% concentrate + 20% I. zollengeriana, D, 60% native grass + 10% concentrate + 30% I. zollengeriana.The results showed that the using of I. zollengeriana until 30% in ration gave the same result with using concentrate of nutrien intake, and milk production but increased the CLA dan PUFA content in milk. The results of this study concluded that I. zollengeriana can increased the content of CLA and PUFA at the use of 75% substitute concentrate in the diet of lactating goats.

Keywords: Indigofera zollengeriana, lactation goat, milk production, CLA, PUFA

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Authors: Kimutai Joan Jepkorir, Moturi Wilkister Nyaora

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The practice of open defecation can be devastating for human health as well as the environment, and this practice persistence could be due to ingrained habits that individuals continue to engage in despite having a better alternative. Safe disposal of human excreta is essential for public health protection. This study sought to find if open defecation relates to fecal-oral infections in Burat and Ngaremara Wards in Isiolo County. This was achieved through conducting a cross-sectional study. Simple random sampling technique was used to select 385 households that were used in the study. Data collection was done by use of questionnaires and observation checklists. The result show that 66% of the respondents disposed-off fecal matter in a safe manner, whereas 34% disposed-off fecal matter in unsafe manner through open defecation. The prevalence proportions per 1000 of diarrhea and intestinal worms among children under-5 years of age were 142 and 21, respectively. The prevalence proportions per 1000 of diarrhea and typhoid among children over-5 years of age were 20 and 20, respectively.

Keywords: faecal-oral infections, open defecation, prevalence proportion, sanitation

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Authors: Sedat Cereci

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This study investigates character of communication, evaluates communication and information need of people, handles relation between communication and contemporary technology, and emphasizes technological lack on communication education in many societies. To get information and communication are of main needs of people and people developed different instruments and technics to learn and to communicate in the past. Because of social need, communication became social matter and governments contributed facilities of communication and set communication places for people to meet and to communicate. Industrial Revolution and technological developments also contributed communication technics and proved numerous technological facilities for communication. Education in the world also use developed technology in any department and communication education especially necessities high technological facilities in schools. Many high schools and universities have communication departments and most of them use contemporary technological facilities, but they are not sufficient. Communication departments in educational organizations in Turkey have computer classrooms, monitors, cameras, microphones, telephones, different softwares, and others. However, despite all this, technological facilities and teaching methods are not sufficient because of contemporary developments. Technology develops rapidly due to hopes of people and technological facilities in education cannot catch developments and people always hope more.

Keywords: information, communication education, technology, technological lack, contemporary conditions, technics

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Authors: D. Díaz Fernández, I. Csízi, K. Pető, G. Nagy

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An outstanding part of the animal products are based on the grasslands, due to the fact that the grassland ecosystems can be found all over the globe. In places where economical and successful crop production cannot be managed, the grassland based animal husbandry can be an efficient way of food production. In addition, these ecosystems have an important role in carbon sequestration, and with their rich flora – and fauna connected to it – in conservation of biodiversity. The protection of nature, and the sustainable agriculture is getting more and more attention in the European Union, but, looking at the consumers’ needs, the production of healthy food cannot be neglected either. Because of these facts, the effects of two specific composts - which are officially authorized in organic farming, in Agri-environment Schemes and Natura 2000 programs – on grass yields and sward compositions were investigated in a field trial. The investigation took place in Hungary, on a natural grassland based on solonetz soil. Three rates of compost (10 t/ha, 20 t/ha, 30 t/ha) were tested on 3 m X 10 m experimental plots. Every treatment had four replications and both type of compost had four-four control plots too, this way 32 experimental plots were included in the investigations. The yield of the pasture was harvested two-times (in May and in September) and before cutting the plots, measurements on botanical compositions were made. Samples for laboratory analysis were also taken. Dry matter yield of pasture showed positive responses to the rates of composts. The increase in dry matter yield was partly due to some positive changes in sward composition. It means that the proportions of grass species with higher yield potential increased in ground cover of the sward without depressing out valuable native species of diverse natural grasslands. The research results indicate that the use of organic compost can be an efficient way to increase grass yields in a sustainable way.

Keywords: compost application, dry matter yield, native grassland, sward composition

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Authors: Christian Doppler, Gernot Hirschl, Gerhard Zsiga

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Starting from 2020, an EU-wide CO2-limitation of 95g/km is scheduled for the average of an OEMs passenger car fleet. Considering that, further measures of optimization on the diesel cycle will be necessary in order to reduce fuel consumption and emissions while keeping performance values adequate at the least. The present article deals with charge air cooling (CAC) on the basis of a diesel passenger car model in a 0D/1D-working process calculation environment. The considered engine is a 2.4 litre EURO VI diesel engine with variable geometry turbocharger (VGT) and low-pressure exhaust gas recirculation (LP EGR). The object of study was the impact of charge air cooling on the engine working process at constant boundary conditions which could have been conducted with an available and validated engine model in AVL BOOST. Part load was realized with constant power and NOx-emissions, whereas full load was accomplished with a lambda control in order to obtain maximum engine performance. The informative results were used to implement a simulation model in Matlab/Simulink which is further integrated into a full vehicle simulation environment via coupling with ICOS (Independent Co-Simulation Platform). Next, the dynamic engine behavior was validated and modified with load steps taken from the engine test bed. Due to the modular setup in the Co-Simulation, different CAC-models have been simulated quickly with their different influences on the working process. In doing so, a new cooler variation isn’t needed to be reproduced and implemented into the primary simulation model environment, but is implemented quickly and easily as an independent component into the simulation entity. By means of the association of the engine model, longitudinal dynamics vehicle model and different CAC models (air/air & water/air variants) in both steady state and transient operational modes, statements are gained regarding fuel consumption, NOx-emissions and power behavior. The fact that there is no more need of a complex engine model is very advantageous for the overall simulation volume. Beside of the simulation with the mentioned demonstrator engine, there have also been conducted several experimental investigations on the engine test bench. Here the comparison of a standard CAC with an intake-manifold-integrated CAC was executed in particular. Simulative as well as experimental tests showed benefits for the water/air CAC variant (on test bed especially the intake manifold integrated variant). The benefits are illustrated by a reduced pressure loss and a gain in air efficiency and CAC efficiency, those who all lead to minimized emission and fuel consumption for stationary and transient operation.

Keywords: air/water-charge air cooler, co-simulation, diesel working process, EURO VI fuel consumption

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Authors: C. Gopi Jinimole, A. Harsha

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For detecting strokes, Computed Tomography (CT) scan is preferred for imaging the abnormalities or infarction in the brain. Because of the problems in the window settings used to evaluate brain CT images, they are very poor in the early stage infarction detection. This paper presents an automatic estimation method for the window settings of the CT images for proper contrast of the hyper infarction present in the brain. In the proposed work the window width is estimated automatically for each slice and the window centre is changed to a new value of 31HU, which is the average of the HU values of the grey matter and white matter in the brain. The automatic window width estimation is based on the average of median of statistical central moments. Thus with the new suggested window centre and estimated window width, the hyper infarction or post-stroke regions in CT brain images are properly detected. The proposed approach assists the radiologists in CT evaluation for early quantitative signs of delayed stroke, which leads to severe hemorrhage in the future can be prevented by providing timely medication to the patients.

Keywords: computed tomography (CT), hyper infarction or post stroke region, Hounsefield Unit (HU), window centre (WC), window width (WW)

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Authors: Gabriel Adesina, Ruixue Cheng, Geetika Aggarwal, Michael Short

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With the global shift towards sustainability and technological advancements, electric Hybrid vehicles (EHVs) are increasingly considered viable alternatives to traditional internal combustion (IC) engine vehicles, which also require efficient cooling systems. The electric Automotive Water Pump (AWP) has been introduced as an alternative to IC engine belt-driven pump systems. However, current control methods for AWPs typically employ fixed gain settings, which are not ideal for the varying conditions of dynamic vehicle environments, potentially leading to overheating issues. To overcome the limitations of fixed gain control, this paper proposes the implementation of an artificial neural network (ANN) for managing the AWP in EHVs. The proposed ANN provides an intelligent, adaptive control strategy that enhances the performance of the AWP, supported through simulation work in MATLAB illustrated in this paper. The comparative analysis demonstrates that while the PID controller provides a fast response of 0.1sec, it has an overshoot of 51.4%. The FLC offers stability and zero overshoot but at the expense of a slower response of 6.7secs. The ANN controller outperforms both, delivering a rapid response of 0.1secs, zero overshoot, 0.0696 IAE, and high precision, making it the most effective control method for AWPs. The ANN’s adaptive learning capabilities allow it to manage the complexities and non-linearity of automotive systems more effectively than traditional control methods.

Keywords: automotive water pump, cooling system, electric hybrid vehicles, artificial neural networks, PID control, fuzzy logic control, IAE, MATLAB

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Authors: Tatsuya Otoshi, Masayuki Murata

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With the development and diversification of applications on the Internet, applications that require high responsiveness, such as video streaming, are becoming mainstream. Application responsiveness is not only a matter of communication delay but also a matter of time required to grasp changes in network conditions. The tradeoff between accuracy and measurement time is a challenge in network control. We people make countless decisions all the time, and our decisions seem to resolve tradeoffs between time and accuracy. When making decisions, people are known to make appropriate choices based on relatively small samples. Although there have been various studies on models of human decision-making, a model that integrates various cognitive biases, called ”quantum decision-making,” has recently attracted much attention. However, the modeling of small samples has not been examined much so far. In this paper, we extend the model of quantum decision-making to model decision-making with a small sample. In the proposed model, the state is updated by value-based probability amplitude amplification. By analytically obtaining a lower bound on the number of samples required for decision-making, we show that decision-making with a small number of samples is feasible.

Keywords: quantum decision making, small sample, MPEG-DASH, Grover's algorithm

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Authors: Radu Deju, Carmen Mustata

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The VVR-S nuclear research reactor owned by Horia Hubulei National Institute of Physics and Nuclear Engineering (IFIN-HH) was designed for research and radioisotope production, being permanently shut-down in 2002, after 40 years of operation. All amount of the nuclear spent fuel S-36 and EK-10 type was returned to Russian Federation (first in 2009 and last in 2012), and the radioactive waste resulted from the reprocessing of it will remain permanently in the Russian Federation. The decommissioning strategy chosen is immediate dismantling. At this moment, the radionuclides with half-life shorter than 1 year have a minor contribution to the contamination of materials and equipment used in reactor department. The decommissioning of the reactor has started in 2010 and is planned to be finalized in 2020, being the first nuclear research reactor that has started the decommissioning project from the South-East of Europe. The management system applied in the decommissioning of the VVR-S research reactor integrates all common elements of management: nuclear safety, occupational health and safety, environment, quality- compliance with the requirements for decommissioning activities, physical protection and economic elements. This paper presents the application of integrated management system in decommissioning of systems, structures, equipment and components (SSEC) from pumps room, including the management of the resulted radioactive waste. The primary cooling system of this type of reactor includes circulation pumps, heat exchangers, degasser, filter ion exchangers, piping connection, drainage system and radioactive leaks. All the decommissioning activities of primary circuit were performed in stage 2 (year 2014), and they were developed and recorded according to the applicable documents, within the requirements of the Regulatory Body Licenses. In the presentation there will be emphasized how the integrated management system provisions are applied in the dismantling of the primary cooling system, for elaboration, approval, application of necessary documentation, records keeping before, during and after the dismantling activities. Radiation protection and economics are the key factors for the selection of the proper technology. Dedicated and advanced technologies were chosen to perform specific tasks. Safety aspects have been taken into consideration. Resource constraints have also been an important issue considered in defining the decommissioning strategy. Important aspects like radiological monitoring of the personnel and areas, decontamination, waste management and final characterization of the released site are demonstrated and documented.

Keywords: decommissioning, integrated management system, nuclear reactor, waste management

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Authors: Vladimir Vinnikov

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The paper proposes a model of an inhomogeneous rock mass with initially random distribution of microcracks on mineral grain boundaries. It describes the behavior of cracks in a medium under the effect of thermal field, the medium heated instantaneously to a predetermined temperature. Crack growth occurs according to the concept of fracture mechanics provided that the stress intensity factor K exceeds the critical value of Kc. The modeling of thermally induced acoustic emission memory effects is based on the assumption that every event of crack nucleation or crack growth caused by heating is accompanied with a single acoustic emission event. Parameters of the thermally induced acoustic emission memory effect produced by cyclic heating and cooling (with the temperature amplitude increasing from cycle to cycle) were calculated for several rock texture types (massive, banded, and disseminated). The study substantiates the adaptation of the proposed model to humidity interference with the thermally induced acoustic emission memory effect. The influence of humidity on the thermally induced acoustic emission memory effect in quasi-homogeneous and banded rocks is estimated. It is shown that such modeling allows the structure and texture of rocks to be taken into account and the influence of interference factors on the distinctness of the thermally induced acoustic emission memory effect to be estimated. The numerical modeling can be used to obtain information about the thermal impacts on rocks in the past and determine the degree of rock disturbance by means of non-destructive testing.

Keywords: crack growth, cyclic heating and cooling, rock texture, thermo acoustic emission memory effect

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Authors: Hammadi Larbi

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The treatment of wastewater in sewage plants usually results in the formation of a large amount of sludge. These appear at the outlet of the treatment plant as a viscous fluid loaded with a high concentration of dry matter. This sludge production presents environmental, ecological, and economic risks. That is why it is necessary to find many solutions for minimizing these risks. In the present article, the effect of hydrogen peroxide, thermal treatment, and quicklime on the characteristics of the activated sludge produced in urban wastewater plant were evaluated in order to avoid any risk in the plants. The study shows increasing of the dose of H2O2 from 0 to 0.4 g causes an increase in the solubilization rate of COD from 12% to 45% and a reduction in the organic matter content of sludge (VM/SM) from 74% to 36% . The results also show that the optimum efficiency of the heat treatment corresponds to a temperature of 80 ° C for a treatment time of 40 min is 47% and 51.82% for a temperature equal to 100 ° C and 76.30 % for a temperature of 120 ° C, and 79.38% for a temperature of 140 ° C. The treatment of sludge by quicklime gives the optimum efficiency of 70.62 %. It was shown the increasing of the temperature from 80°C to 140°C, the pH of sludge was increased from 7.12 to 9.59. The obtained results showed that with increasing the dose of quicklime from 0 g/l to 1g/l in activated sludge led to an increase of their pH from 7.12 to 12.06. The study shows the increasing the dose of quicklime from 0 g/l to 1g/l causes also an increase in the solubilization of COD from 0% to 70.62 %

Keywords: activated sludge, hydrogen peroxide, thermal treatment, quicklime

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Authors: Noor-ul-Ain, Muhammad Tahir Khan, Kashif Khan, Adeela Ajmal, Hamid Mustafa

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The objective of this study was to evaluate the preservative and upgrading potential of urea (70g/kg DM) added to high moisture oat silage at laboratory scale trial and urea was hydrolysed 95%. Microbial activity measured by pH and volatile fatty acids (VFA) and lactate production was reduced (p<0.001) by the urea addition. The pH of oat silage (without treated) was measured 5.7 and increased up to 8.00 on average while; volatile fatty acids (VFA) concentration was decreased. Relative proportions of fermentation acids changed after urea addition, increasing the acetate and butyrate and decreasing the propionate and lactate proportions. The addition of urea to oat silages increased (P<0.001) water soluble and ammonium nitrogen of the forage. These nitrogen fractions represented more than 40% of total nitrogen. After urea addition, total nitrogen content of oat silages increased from 21.0 g/kg DM to 28 g/kg DM. Application of urea at a rate of 70 g/kg DM significantly increased (P<0.001) the in situ degradation of neutral-detergent fibre after 48h of rumen incubation (NDF-situ). The NDF-situ was 200 g/kg NDF higher on oat forages ensiled with urea than on oat forages ensiled without urea. Oat silages can be effectively preserved and upgraded by ensiling with 70 g urea/kg dry matter. Further studies are required to evaluate voluntary intake of this forage.

Keywords: oat, silage, urea, pH, forage

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Authors: Wium de Villiers

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Section 106(1)(h) of the South African Criminal Procedure Act 51 of 1977 provides that an accused may enter a special plea that the prosecutor does not have title to prosecute. In a seminal matter (S v Mousa 2021 2 SACR 378 (GJ)) regarding section 106(1)(h), certain interesting legal aspects emerged. The first aspect concerned the meaning of the term “prosecutor”. More specifically, the question arose whether the term included a prosecutor who was previously involved with the matter, as well as the relevant Deputy Director of Public Prosecutions (DDPP) who instituted the prosecution and oversaw the prosecution on behalf of the state. The meaning of the term “title”, and with regard to the conduct of the “prosecutor”, the term “abuse of process,” were also raised and decided. In the paper, the facts, and the arguments in, and the decisions of the court, are discussed critically. The author argue that the intended objection in section 106(1)(h) is not to cure the abuse inflicted by a previous prosecutor or by the DDPP. I point out that the term “title” includes a lack of authority, non-compliance with jurisdictional requirements or absence of locus standi. I also point out that an abuse of process takes place if the process is used for an improper, ulterior or collateral purpose. I also argue that the accused should, instead of relying on section 106(1)(h), have relied on the prior agreement and applied for a permanent stay of prosecution.

Keywords: special plea, prosecutor, title, abuse of process

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Authors: Roslina Che Soh

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Best interest of the child has been the prevailing principle of the custody legislations of most nations in the world. The tremendous shift from parental rights to parental responsibilities throughout the centuries had made the principle of best interests of the child as the utmost matter which parents must uphold in child upbringing. Despite the commitment to this principle is significantly enshrined in the United Nation Convention on Rights of the Child, the content and application of the principle differs across borders. Differences persist notwithstanding many countries have experienced a substantial shift over the last several decades in the types of custodial arrangements that are thought to best serve children’s interests. The laws in Malaysia similarly uphold this principle but do not provide further deliberation on the principle itself. The principle is entirely developed by the courts through decided cases. Thus, this paper seeks to discuss the extent of the application of best interest of the child principle in custody disputes. In doing so, it attempts to provide an overview of the current laws and the approach of the Civil and the Shariah courts in Malaysia in applying the principle in determining custody disputes. For purposes of comparison, it briefly examines the legislations and the courts practices in Australia and England on this matter. The purpose is to determine the best standard to be adopted by Malaysia and to propose improvement to the laws whenever appropriate.

Keywords: child custody, best interest, Malaysian law, bioinformatics, biomedicine

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Authors: Rahmat Ali, Inamullah Khan, Amjad Naseer, Abid A. Shah

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Hydronic Heating and Cooling systems in concrete slab based buildings are increasingly becoming a popular substitute to conventional heating and cooling systems. In exploring the materials, techniques employed, and their relative performance measures, a fair bit of uncertainty exists. This research has identified the simplest method of determining the thermal field of a single hydronic pipe when acting as a part of a concrete slab, based on which the spacing and positioning of pipes for a best thermal performance and surface temperature control are determined. The pipe material chosen is the commonly used PEX pipe, which has an all-around performance and thermal characteristics with a thermal conductivity of 0.5W/mK. Concrete Test samples were constructed and their thermal fields tested under varying input conditions. Temperature sensing devices were embedded into the wet concrete at fixed distances from the pipe and other touch sensing temperature devices were employed for determining the extent of the thermal field and validation studies. In the first stage, it was found that the temperature along a specific distance was the same and that heat dissipation occurred in well-defined layers. The temperature obtained in concrete was then related to the different control parameters including water supply temperature. From the results, the temperature of water required for a specific temperature rise in concrete is determined. The thermally effective area is also determined which is then used to calculate the pipe spacing and positioning for the desired level of thermal comfort.

Keywords: thermally activated building systems, concrete slab temperature, thermal field, energy efficiency, thermal comfort, pipe spacing

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Authors: Kanika Taneja, V. K. Soni, Kafeel Ahmad, Shamshad Ahmad

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A severe dust storm generated from a western disturbance over north Pakistan and adjoining Afghanistan affected the north-west region of India between May 28 and 31, 2014, resulting in significant reductions in air quality and visibility. The air quality of the affected region degraded drastically. PM10 concentration peaked at a very high value of around 1018 μgm-3 during dust storm hours of May 30, 2014 at New Delhi. The present study depicts aerosol optical properties monitored during the dust days using ground based multi-wavelength Sky radiometer over the National Capital Region of India. High Aerosol Optical Depth (AOD) at 500 nm was observed as 1.356 ± 0.19 at New Delhi while Angstrom exponent (Alpha) dropped to 0.287 on May 30, 2014. The variation in the Single Scattering Albedo (SSA) and real n(λ) and imaginary k(λ) parts of the refractive index indicated that the dust event influences the optical state to be more absorbing. The single scattering albedo, refractive index, volume size distribution and asymmetry parameter (ASY) values suggested that dust aerosols were predominant over the anthropogenic aerosols in the urban environment of New Delhi. The large reduction in the radiative flux at the surface level caused significant cooling at the surface. Direct Aerosol Radiative Forcing (DARF) was calculated using a radiative transfer model during the dust period. A consistent increase in surface cooling was evident, ranging from -31 Wm-2 to -82 Wm-2 and an increase in heating of the atmosphere from 15 Wm-2 to 92 Wm-2 and -2 Wm-2 to 10 Wm-2 at top of the atmosphere.

Keywords: aerosol optical properties, dust storm, radiative transfer model, sky radiometer

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Authors: Y. Vásquez, F. Reyes, P. Oyola, M. Rubio, J. Muñoz, E. Lissi

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In several cities in Chile, there is significant urban pollution, particularly in Santiago and in cities in the south where biomass is used as fuel in heating and cooking in a large proportion of homes. This has generated interest in knowing what factors can be modulated to control the level of pollution. In this project was conditioned and set up a photochemical chamber (14m3) equipped with gas monitors e.g. CO, NOX, O3, others and PM monitors e.g. dustrack, DMPS, Harvard impactors, etc. This volume could be exposed to UVA lamps, producing a spectrum similar to that generated by the sun. In this chamber, PM and gas emissions associated with biomass burning were studied in the presence and absence of radiation. From the comparative analysis of wood stove (eucalyptus globulus) and pellet (radiata pine), it can be concluded that, in the first approximation, 9-nitroanthracene, 4-nitropyrene, levoglucosan, water soluble potassium and CO present characteristics of the tracers. However, some of them show properties that interfere with this possibility. For example, levoglucosan is decomposed by radiation. The 9-nitroanthracene, 4-nitropyrene are emitted and formed under radiation. The 9-nitroanthracene has a vapor pressure that involves a partition involving the gas phase and particulate matter. From this analysis, it can be concluded that K+ is compound that meets the properties known to be tracer. The PM2.5 emission measured in the automatic pellet stove that was used in this thesis project was two orders of magnitude smaller than that registered by the manual wood stove. This has led to encouraging the use of pellet stoves in indoor heating, particularly in south-central Chile. However, it should be considered, while the use of pellet is not without problems, due to pellet stove generate high concentrations of Nitro-HAP's (secondary organic contaminants). In particular, 4-nitropyrene, compound of high toxicity, also primary and secondary particulate matter, associated with pellet burning produce a decrease in the size distribution of the PM, which leads to a depth penetration of the particles and their toxic components in the respiratory system.

Keywords: biomass burning, photochemical chamber, particulate matter, tracers

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Authors: Lucero Luciano, Cesar Celis, Jose Ramos

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Polygeneration improves energy efficiency and reduce both energy consumption and pollutant emissions compared to conventional generation technologies. A polygeneration system is a variation of a cogeneration one, in which more than two outputs, i.e., heat, power, cooling, water, energy or fuels, are accounted for. In particular, polygeneration systems integrating solar energy and water desalination represent promising technologies for energy production and water supply. They are therefore interesting options for coastal regions with a high solar potential, such as those located in southern Peru and northern Chile. Notice that most of the Peruvian and Chilean mining industry operations intensive in electricity and water consumption are located in these particular regions. Accordingly, this work focus on the design and integration of a polygeneration system producing industrial heating, cooling, electrical power and water for an industrial plant. The design procedure followed in this work involves integer linear programming modeling (MILP), operational planning and dynamic operating conditions. The technical and economic feasibility of integrating renewable energy technologies (photovoltaic and solar thermal, PV+CPS), thermal energy store, power and thermal exchange, absorption chillers, cogeneration heat engines and desalination technologies is particularly assessed. The polygeneration system integration carried out seek to minimize the system total annual cost subject to CO2 emissions restrictions. Particular economic aspects accounted for include investment, maintenance and operating costs.

Keywords: desalination, design and integration, polygeneration systems, renewable energy

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Authors: Michael Graz, Natasha Hurril, Andrew Shearer

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Research on feed supplementation with natural compounds is currently being intensively pursued with a view to improving energy utilisation in ruminants and mitigating the production of methane by these animals. Towards this end, a novel combination of extracts from garlic and bitter orange was therefore selected for trials on the basis of their previously published in vitro anti-methanogenic potential. Three separate in vitro experiments were conducted to determine energy utilisation and greenhouse gas production. These included use of rumen fluid from fistulated cows and sheep in batch culture, the Hohenheim gas test, and the Rusitec technique. Experimental and control arms were utilised, with 5g extracts per kilogram of total dietary dry matter (0.05g/kg active compounds) being used to supplement or not supplement the in vitro systems. Respiratory measurements were conducted on experimental day 1 for the batch culture and Hohenheim gas test and on day 14-21 for the Rusitec Technique (in a 21-day trial). Measurements included methane (CH4) production, total volatile fatty acid (VFA) concentration, molar proportions of acetate, propionate and butyrate and degradation of organic matter (Rusitec). CH4 production was reduced by 82% (±16%), 68% (±11%) and 37% (±4%) in the batch culture, Hohenheim gas test and Rusitec, respectively. Total VFA production was reduced by 13% (±2%) and 2% (±0.1%) in the batch culture and Hohenheim gas test whilst it was increased by 8% (±2%) in the Rusitec. Total VFA production was reduced in all tests between 2 and 10%, whilst acetate production was reduced between 10% and 29%. Propionate production which is an indicator of weight gain was increased in all cases between 16% and 30%. Butyrate production which is considered an indicator of potential milk yield was increased by between 6 and 11%. Degradation of organic matter in the Rusitec experiments was improved by 10% (±0.1%). In conclusion, the study demonstrated the potential of the combination of garlic and citrus extracts to improve digestion, enhance body energy retention and limit CH4 formation in relation to feed intake.

Keywords: citrus, garlic, methane, ruminants

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Authors: Zouhaier Nasr, Mohamed Nouri

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The increase in greenhouse gases since the pre-industrial period is a real threat to disrupting the balance of marine and terrestrial ecosystems. Along with the oceans, forest soils are considered to be the planet's second-largest carbon sink. North African forests have been subject to alarming degradation for several decades. The objective of this investigation is to determine and quantify the effect of thinning practiced in pine forests in northern Tunisia on the storage of organic carbon in the trees and in the soil. The plot planted in 1989 underwent thinning in 2005 on to plots; the density is therefore 1600 trees/ha in control and 400 trees/ha in thinning. Direct dendrometric measurements (diameter, height, branches, stem) were taken. In the soil part, six profiles of 1m / 1m / 1m were used for soil and root samples and biomass and organic matter measurements. The measurements obtained were statistically processed by appropriate software. The results clearly indicate that thinning improves tree growth, so the diameter increased from 24.3 cm to 30.1 cm. Carbon storage in the trunks was 35% more and 25% for the whole tree. At ground level, the thinned plot shows a slight increase in soil organic matter and quantity of carbon per tree, exceeding the control by 10 to 25%.

Keywords: forest, soil, carbon, climate change, Tunisia

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Authors: Nicholas Sehube, Rosemary Kelebemang, Pogisego Dinake

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The extent of Pb contamination of shooting range soils has never been ascertained in Botswana, this was the first attempt in evaluating the deposition of Pb into the soils emanating from munitions. A total of 8 military shooting ranges were used for this study. Soil samples were collected at each of the 8 shooting ranges at the berm (stop butt), target line, 50 and 100 m from the berm. In all of the shooting ranges investigated the highest concentrations were found in the berm soils. The highest Pb concentrations of 38 406.87 mg/Kg were found in the berm soils of Thebephatshwa shooting range which is enclosed within a military camp with staff residential dwelling only a kilometre away. Most of the shooting ranges soils contained elevated levels of Pb in the ranges above 2000 mg/kg far exceeding the United States Environmental Protection Agency (USEPA) critical value of 400 mg/Kg. Mobilization of lead at high pH is attributed to low organic matter and such was the case with Thebephatshwa shooting range with a percept organic matter of 0.35±0.08. The predominant weathering products in these shooting ranges were cerussite (PbCO3), hydrocerussite (Pb(CO3)2(OH)2 and massicot (PbO). The detailed examination and characterization of the extent of pollution will help in the development and implementation of scientifically sound remediation and restoration of shooting ranges soils.

Keywords: ammunition, Botswana, Pb, pollution, soil

Procedia PDF Downloads 226

Authors: M. Fertouna Bellakhal, M. Bellakhal, A. Dhib, A. Fathalli, S. Turki, L. Aleya

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Study of dinoflagellate cysts is a precious tool to get information about environment and water quality in many aquatic ecosystems. The distribution of Alexandrium pacificum cysts, in Bizerta lagoon located in North of Tunisia, was made based on sediment samples analysis from 123 equidistant stations delimiting 125 km² surfaces. Sediment characteristics such as percentage of water, organic matter, and particle size were analyzed to determine the factors that influence the distribution of this dinoflagellate. In addition, morphological examination and ribotyping of vegetative forms from microalgal cultures made from cyst germination confirmed the identity of the species attributed to A. pacificum. A correlation between the abundance of A. pacificum cysts and the percentage of water and sediment organic matter was recorded. In addition, the sedimentary fraction < 63μm was found to be potentially favorable for the installation and initiation of the Alexandrium pacificum efflorescence at the Bizerte lagoon. The mapping of cysts in this aquatic ecosystem has also allowed us to define distinct areas with specific abundance with closed relationship with shellfish aquaculture stations located within the lagoon.

Keywords: Alexandrium pacificum, cysts, Dinoflagellate, microalgal culture

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Authors: Sandeep Bandarwadkar, Tadas Zdankus

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To maintain a comfortable indoor temperature for its residents in the colder season, heating a building is necessary. Due to the expansion in the construction sectors, the consumption of heating energy is increasing. According to Eurostat data, in the European Union, the share of energy consumption of heating energy for space and cooling in residential buildings was around 63% in 2019. These figures indicate that heating energy still accounts for a significant portion of total energy consumption in Europe. Innovation is crucial to reduce energy consumption in buildings and achieve greater energy efficiency and sustainability. It can bring about new solutions that are smarter and more natural energy generation to reduce greenhouse gas emissions. The ground can serve as an effective and sustainable heat accumulator for heating and cooling. The temperature of the ground is higher than that of the ambient air in the colder period and lower in the warmer period. The building deep in the soil could use less thermal energy compared to the above-ground buildings that provide the same amount of thermal comfort. The temperature difference between the soil and the air inside the building decreases as the temperature of the soil increases. In progress, this process generates the condition that acts against heat loss. However, heat dissipates further to the consecutive layers and reaches thermal equilibrium. The charging of the ground by heat and its dissipation through the adjacent soil layers was investigated experimentally. The results of this research showed that 9% of the energy savings in partially underground buildings and 44.4% in completely underground buildings were derived from heating the space. Heat loss to the ground is treated as a charge of the soil by thermal energy. The dependence of the intensity of the charge on time was analysed and presented.

Keywords: heat transfer, accumulation of heat, underground building, soil charge

Procedia PDF Downloads 65