Search results for: natural fiber

Authors: Naif A. Haddad

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Greek, Hellenistic and Roman theatre heritage are exposed to multiple risks at varied times or simultaneously. There is no single reason why a theatre building becomes ‘at risk’, as each case has different circumstances which have led to the theatre building decay. There are complicated processes of destruction and distress that show divergence in theatre building materials' decay. Theatre modern use for cultural performances causes much of the risks concerning the physical structure and authenticity of theatre sites. In addition, there are some deterioration and deformations due to previous poor quality restorations and interventions through related excavation and conservation programmes as also risks to authenticity due to new additions. For preventive conservation, theatre natural and anthropogenic risks management can provide a framework for decision making. These risks to ancient theatre heritage may stem from exposure to one or more risk or synergy of many factors. We, therefore, need to link the theatre natural risks to the risks that come from anthropogenic factors associated with social and economic development. However, this requires a holistic approach, and systematic methodology for understanding these risks from various sources while incorporating specific actions, planning and strategies for each specific risk. Elaborating on recent relevant studies, and ERATO and ATHENA EU projects for ancient theaters and odea and general surveys, this paper attempts to discuss the main aspects of the ancient Greek, Hellenistic and Roman theatres risk related issues. Relevant case studies shall also be discussed and investigated to examine frameworks for risk mitigation, and related guidelines and recommendations that provide a systematic approach for sustainable management and planning in relation mainly to ‘compatible use’ of theatre sites.

Keywords: cultural heritage management, European ancient theatres projects, Anthropogenic risks mitigation, sustainable management and planning, preventive conservation, modern use, compatible use

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Authors: Kartikey Gupta

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Global warming and environmental degradation are at their peak today, with the years after 2000A.D. giving way to 15 hottest years in terms of average temperatures. In India, much of the standard temperature measuring equipment are located in ‘developed’ urban areas, hence showing us an incomplete picture in terms of the climate across many rural areas, which comprises most of the landmass. This study showcases data studied by the author since 3 years at Vatsalya’s Children’s village, in outskirts of Jaipur, Rajasthan, India; in the midst of semi-arid topography, where consistently huge temperature differences of up to 15.8 degrees Celsius from local Jaipur weather only 30 kilometers away, are stunning yet scary at the same time, encouraging analysis of where the natural climatic pattern is heading due to rapid unrestricted urbanization. Record-breaking data presented in this project enforces the need to discuss causes and recovery techniques. This research further explores how and to what extent we are causing phenomenal disturbances in the natural meteorological pattern by urban growth. Detailed data observations using a standardized ambient weather station at study site and comparing it with closest airport weather data, evaluating the patterns and differences, show striking differences in temperatures, wind patterns and even rainfall quantity, especially during high-pressure zone days. Winter-time lows dip to 8 degrees below freezing with heavy frost and ice, while only 30 kms away minimum figures barely touch single-digit temperatures. Human activity is having an unprecedented effect on climatic patterns in record-breaking trends, which is a warning of what may follow in the next 15-25 years for the next generation living in cities, and a serious exploration into possible solutions is a must.

Keywords: climate change, meteorology, urban heat island, urbanization

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Authors: Shanlong Lu, Jiming Jin, Xiaochun Wang

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The Tibetan Plateau has the largest number of inland lakes with the highest elevation on the planet. These massive and large lakes are mostly in natural state and are less affected by human activities. Their shrinking or expansion can truly reflect regional climate and environmental changes and are sensitive indicators of global climate change. However, due to the sparsely populated nature of the plateau and the poor natural conditions, it is difficult to effectively obtain the change data of the lake, which has affected people's understanding of the temporal and spatial processes of lake water changes and their influencing factors. By using the MODIS (Moderate Resolution Imaging Spectroradiometer) MOD09Q1 surface reflectance images as basic data, this study produced the 8-day lake water surface data set of the Tibetan Plateau from 2000 to 2012 at 250 m spatial resolution, with a lake water surface extraction method of combined with lake water surface boundary buffer analyzing and lake by lake segmentation threshold determining. Then based on the dataset, the lake water surface variations and their influencing factors were analyzed, by using 4 typical natural geographical zones of Eastern Qinghai and Qilian, Southern Qinghai, Qiangtang, and Southern Tibet, and the watersheds of the top 10 lakes of Qinghai, Siling Co, Namco, Zhari NamCo, Tangra Yumco, Ngoring, UlanUla, Yamdrok Tso, Har and Gyaring as the analysis units. The accuracy analysis indicate that compared with water surface data of the 134 sample lakes extracted from the 30 m Landsat TM (Thematic Mapper ) images, the average overall accuracy of the lake water surface data set is 91.81% with average commission and omission error of 3.26% and 5.38%; the results also show strong linear (R2=0.9991) correlation with the global MODIS water mask dataset with overall accuracy of 86.30%; and the lake area difference between the Second National Lake Survey and this study is only 4.74%, respectively. This study provides reliable dataset for the lake change research of the plateau in the recent decade. The change trends and influencing factors analysis indicate that the total water surface area of lakes in the plateau showed overall increases, but only lakes with areas larger than 10 km2 had statistically significant increases. Furthermore, lakes with area larger than 100 km2 experienced an abrupt change in 2005. In addition, the annual average precipitation of Southern Tibet and Southern Qinghai experienced significant increasing and decreasing trends, and corresponding abrupt changes in 2004 and 2006, respectively. The annual average temperature of Southern Tibet and Qiangtang showed a significant increasing trend with an abrupt change in 2004. The major reason for the lake water surface variation in Eastern Qinghai and Qilian, Southern Qinghai and Southern Tibet is the changes of precipitation, and that for Qiangtang is the temperature variations.

Keywords: lake water surface variation, MODIS MOD09Q1, remote sensing, Tibetan Plateau

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Authors: G. Judakova, M. Bause

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The ability to model and simulate numerically natural gas flow in pipelines has become of high importance for the design of pipeline systems. The understanding of the formation of hydrate particles and their dynamical behavior is of particular interest, since these processes govern the operation properties of the systems and are responsible for system failures by clogging of the pipelines under certain conditions. Mathematically, natural gas flow can be described by multiphase flow models. Using the two-fluid modeling approach, the gas phase is modeled by the compressible Euler equations and the particle phase is modeled by the pressureless Euler equations. The numerical simulation of compressible multiphase flows is an important research topic. It is well known that for nonlinear fluxes, even for smooth initial data, discontinuities in the solution are likely to occur in finite time. They are called shock waves or contact discontinuities. For hyperbolic and singularly perturbed parabolic equations the standard application of the Galerkin finite element method (FEM) leads to spurious oscillations (e.g. Gibb's phenomenon). In our approach, we use stabilized FEM, the streamline upwind Petrov-Galerkin (SUPG) method, where artificial diffusion acting only in the direction of the streamlines and using a special treatment of the boundary conditions in inviscid convective terms, is added. Numerical experiments show that the numerical solution obtained and stabilized by SUPG captures discontinuities or steep gradients of the exact solution in layers. However, within this layer the approximate solution may still exhibit overshoots or undershoots. To suitably reduce these artifacts we add a discontinuity capturing or shock capturing term. The performance properties of our numerical scheme are illustrated for two-phase flow problem.

Keywords: two-phase flow, gas-particle mixture, inviscid two-fluid model, euler equation, finite element method, streamline upwind petrov-galerkin, shock capturing

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Authors: Jaya Bishnu Pradhan

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Weaving mat is one of the common activities performed in different community generally in the rural part of Nepal. Mat weavers’ practice mathematical ideas and concepts implicitly in order to perform their job. This study is intended to uncover the mathematical ideas embedded in mat weaving that can help teachers and students for the teaching and learning of school geometry. The ethnographic methodology was used to uncover and describe the beliefs, values, understanding, perceptions, and attitudes of the mat weavers towards mathematical ideas and concepts in the process of mat weaving. A total of 4 mat weavers, two mathematics teachers and 12 students from grade level 6-8, who are used to participate in weaving, were selected for the study. The whole process of the mat weaving was observed in a natural setting. The classroom observation and in-depth interview were taken with the participants with the help of interview guidelines and observation checklist. The data obtained from the field were categorized according to the themes regarding mathematical ideas embedded in the weaving activities, and its possibilities in teaching learning of school geometry. In this study, the mathematical activities in different sectors of their lives, their ways of understanding the natural phenomena, and their ethnomathematical knowledge were analyzed with the notions of pluralism. From the field data, it was found that the mat weaver exhibited sophisticated geometrical ideas in the process of construction of frame of mat. They used x-test method for confirming if the mat is rectangular. Mat also provides a good opportunity to understand the space geometry. A rectangular form of mat may be rolled up when it is not in use and can be converted to a cylindrical form, which usually can be used as larder so as to reserve food grains. From the observation of the situations, this cultural experience enables students to calculate volume, curved surface area and total surface area of the cylinder. The possibilities of incorporation of these cultural activities and its pedagogical use were observed in mathematics classroom. It is argued that it is possible to use mat weaving activities in the teaching and learning of school geometry.

Keywords: ethnography, ethnomathematics, geometry, mat weaving, school pedagogy

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Authors: Muhammad Arsalan Mahmoo, Allah Rakha, Muhammad Sohail

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The supplementation of wheat flour with high lysine legume flours has positive effects on the nutritional value of bread. In present study, germinated and terminated soya flour blends were prepared and supplemented in bread in variable proportions (10 % and 20 % of each) to check its impact on quality and sensory attributes of bread. The results showed that there was a significant increase in protein, ash and crude fat contents due to increase in the level of germinated and ungerminated soya flour. However, the moisture and crude fiber contents of composite flours containing germinated and ungerminated soya flour decreased with increased level of supplementation. Mean values for physical analysis (loaf volume, specific volume, weight loss and force for texture) were significantly higher in breads prepared with germinated soya bean flour.The scores assigned to sensory parameters of breads like volume, color of crust, symmetry, color of crumb, texture, taste and aroma decreased significantly by increasing the level of germinated and ungerminated soya flour in wheat flour while color of crust and taste slightly improved. The scores given to overall acceptability of bread prepared from composite flour supplemented with 10 % germinated soya flour.

Keywords: composite bread, protein energy malnutrition, supplementation, amino acid profile, grain legumes

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Authors: Pujan Sarkar

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Frictional behavior of glass epoxy and Al particulate glass-epoxy composites sliding against mild steel are investigated experimentally at normal atmospheric condition. Glass epoxy (0 wt% Al) and 5, 10 and 15 wt% Al particulate filled glass-epoxy composites are fabricated in conventional hand lay-up technique followed by light compression moulding process. A pin on disc type friction apparatus is used under dry sliding conditions. Experiments are carried out at a normal load of 5-50 N, and sliding speeds of 0.5-5.0 m/s for a fixed duration. Variations of friction coefficient with sliding time at different loads and speeds for all the samples are considered. Results show that the friction coefficient is influenced by sliding time, normal loads, sliding speeds, and wt% of Al content. In general, with respect to time, friction coefficient increases initially with a lot of fluctuations for a certain duration. After that, it becomes stable for the rest of the experimental time. With the increase of normal load, friction coefficient decreases at all speed levels and for all the samples whereas, friction coefficient increases with the increase of sliding speed at all normal loads for glass epoxy and 5 wt% Al content glass-epoxy composites. But for 10 and 15 wt%, Al content composites at all loads, reverse trend of friction coefficient has been recorded. Under different tribological conditions, the suitability of composites in respect of wt% of Al content is noted, and 5 wt% Al content glass-epoxy composite reports as the lowest frictional material at all loads compared to other samples.

Keywords: Al powder, composite, epoxy, friction, glass fiber

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Authors: Nicolò Vaiana, Giorgio Serino

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In this paper, an advanced Nonlinear Exponential Model (NEM), able to simulate the uniaxial dynamic behavior of seismic isolators having a continuously decreasing tangent stiffness with increasing displacement in the relatively large displacements range and a hardening or softening behavior at large displacements, is presented. The mathematical model is validated by comparing the experimental force-displacement hysteresis loops obtained during cyclic tests, conducted on a helical wire rope isolator and a recycled rubber-fiber reinforced bearing, with those predicted analytically. Good agreement between the experimental and simulated results shows that the proposed model can be an effective numerical tool to predict the force-displacement relationship of seismic isolation devices within the large displacements range. Compared to the widely used Bouc-Wen model, unable to simulate the response of seismic isolators at large displacements, the proposed one allows to avoid the numerical solution of a first order nonlinear ordinary differential equation for each time step of a nonlinear time history analysis, thus reducing the computation effort. Furthermore, the proposed model can simulate the smooth transition of the hysteresis loops from small to large displacements by adopting only one set of five parameters determined from the experimental hysteresis loops having the largest amplitude.

Keywords: base isolation, hardening behavior, nonlinear exponential model, seismic isolators, softening behavior

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Authors: Nadia Allouache, Omar Rahli

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Many promising technologies have been developed to harness the sun's energy. These technologies help in economizing energy and environmental protection. The solar refrigerating systems are one of these important technologies. In addition to environmental benefits and energy saving, adsorption refrigerating systems have many advantages such as lack of moving parts, simplicity of construction and low operating costs. The work aimed to establish the main factors that affect the performances of an adsorption refrigerating system using different geometries of adsorbers and different adsorbent-adsorbate pairs. The numerical modeling of the heat and mass transfer in the system, using various working pairs, such as: activated carbon-ammonia, calcium chlorid-ammonia, activated carbon fiber- methanol and activated carbon AC35-methanol, show that the adsorber design can influence the system performances; The thermal performances of system are better in the annular configuration case. An optimal value of generating temperature is observed in annular adsorber case for which the thermal performance of the cooling system is maximal. While in the plate adsorber, above a certain value of generating temperature, the performance of the system remains almost constant. The environmental conditions such as solar radiation and pressure have a great influence in the system efficiency, and the choice of the working pair depends on the environmental conditions and the geometry of the adsorber.

Keywords: adsorber geometry, numerical modeling, optimal environmental conditions, working pairs.

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Authors: Abir Mohamed Mohamed Ibrahim, Amina Titouche, Mohamed Hazzit

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Phytotherapy is based on use of plant natural products holding the main sources of drugs with healing properties for the treatment of human, animal or vegetable diseases. With these aims, and to replace chemical preservatives in natural products, we are interested to use essential oils from Algerian endemic plants belonging to the Asteraceae family: Artemisia herba alba Asso, which was undergoes a hydro-distillation after its irradiation by Gamma rays at frequencies: 10, 20, and 30 KGray which gave respectively the following essential oil yields: 1.087%, 1.087%, 1.085%, compared with that of the untreated sample giving a yield of 1.27 %. Evaluation of the antioxidant activity in vitro of essential oil for A. herba alba has been assessed by two different methods: inhibition of DPPH radical and measurement of reducing power. The first method has not revealed a very big difference regardless of the dose of irradiation, the IC50 is about 4000 mg/l, the maximum of inhibition was around 49.4%, likewise, the test of reducing power awarded us a maximum reducing capacity was of 0.76%; both of results were registered by the specimen irradiated at 20 KGy, it has a more better antioxidant power than no irradiated sample but slightly. To combat Fusarium culmorum, causing the wilts and rots, we are focused on the antifungal screening of this aromatic plant. The results obtained, followed by measurements of Minimal Inhibitory Concentrations (MIC); showed promising inhibitory effect against pathogen tested. With a yield superior to l%, the essential oil has shown a remarkable efficiency on the stump, mainly for sample irradiate at 30KGray (MICs= 625 µg/ml; MICc= 1250 µg/ml) with MIC of 2%. These results demonstrate a good antifungal activity, to limit and even to stop the development of the pathogenic microorganism and also the positive effect of dose of irradiation to upgrade this capacity as well, to uphold the antioxidant capacity.

Keywords: artemisia herba alba Asso, essential oil yield, gamma ray, antioxidant activity, antifungal activity

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Authors: I. T. Makhubedu, B. A. Letty, P. F. Scogings, P. L. Mafongoya

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Despite their potential importance in recycling dinitrogen (N2) fixed in alley cropping systems, the effects of tree pruning residues on symbiotic N2 fixation are poorly studied. A 2 x 2 x 2 factorial experiment was conducted to evaluate the effects of pruning residue management and pruning date on symbiotic performance and

Keywords: alley cropping, management, N₂ fixed, natural abundance, recycling

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Authors: Chia-Lin Tu

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Towards the end of the 20th century, a reductive picture has dominated in philosophy of science and philosophy of mind. Reductive physicalism claims that all entities and properties in this world are eventually able to be reduced to the physical level. It means that all phenomena in the world are able to be explained by laws of physics. However, quantum physics provides another picture. It says that the world is undergoing change and the energy of change is, in fact, the most important part to constitute world phenomena. Quantum physics provides us another point of view to reconsider the reality of the world. Throughout the history of philosophy of mind, reductive physicalism tries to reduce the conscious phenomena to physical particles as well, meaning that the reality of consciousness is composed by physical particles. However, reductive physicalism is unable to explain conscious phenomena and mind-body causation. Conscious phenomena, e.g., qualia, is not composed by physical particles. The current popular theory for consciousness is emergentism. Emergentism is an ambiguous concept which has not had clear idea of how conscious phenomena are emerged by physical particles. In order to understand the emergence of conscious phenomena, it seems that quantum physics is an appropriate analogy. Quantum physics claims that physical particles and processes together construct the most fundamental field of world phenomena, and thus all natural processes, i.e., wave functions, have occurred within. The traditional space-time description of classical physics is overtaken by the wave-function story. If this methodology of quantum physics works well to explain world phenomena, then it is not necessary to describe the world by the idea of physical particles like classical physics did. Conscious phenomena are one kind of world phenomena. Scientists and philosophers have tried to explain the reality of them, but it has not come out any conclusion. Quantum physics tells us that the fundamental field of the natural world is processed metaphysics. The emergence of conscious phenomena is only possible within this process metaphysics and has clearly occurred. By the framework of quantum physics, we are able to take emergence more seriously, and thus we can account for such emergent phenomena as consciousness. By questioning the particle-mechanistic concept of the world, the new metaphysics offers an opportunity to reconsider the reality of conscious phenomena.

Keywords: quantum physics, reduction, emergence, qualia

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Authors: Iyiola Olusola Oluwaleye, Samson A. Adeleye, Omojola Awogbemi

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This paper reports an investigation of the comparative effects of drying on the quality of some leafy vegetables at three different temperatures namely: 50ᵒC, 60ᵒC and 70ᵒC. The vegetables investigated are spinach (Amaranthus cruentus); water leaf (Talinum triangulare); lettuce (Lactuca satuva); and fluted pumpkin (Telfaria occidentalis). These vegetables are available in abundance during raining season and are commonly consumed by average Nigerians. A convective dryer was used for the drying process at the stipulated temperatures which were maintained with the aid of a thermostat. The vegetable samples after washing was cut into smaller sizes of 0.4 cm-0.5 cm and loaded into the drying cage of the convective dryer. The daily duration of the drying is six hours from 9:00 am to 3:00 pm. The dried samples were thereafter subjected to microbial and proximate analyses. The result of the tests shows that the microbial load decreases as the drying temperature increases. As temperature increases, the moisture content and carbohydrate of all the samples decreases while the crude fiber, ash and protein increases. Percentage fat content decreases as drying temperature increases with the exception of fluted pumpkin. The shelf life of the vegetable samples increase with drying temperature, Spinach has the lowest shelf life followed by Fluted Pumpkin, followed by lettuce while Water Leaf has the highest shelf life at the three drying temperatures of 50ᵒC, 60ᵒC and 70ᵒC respectively.

Keywords: convective drying, leafy vegetables, quality, shelf life

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Authors: Vaishali Joshi

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In the past, companies and buyers operated as if there was infinite availability of natural resources for usage, which has resulted in the loss of our globe's natural ecosystem. People's consciousness of ecological concerns had increased, which showed the way for the evolution of the green revolution with the objective of discontinuing the use of products that are harmful to the ecosystem of the earth. This green revolution has made the consumers head toward those companies which are providing eco-friendly products s/service s through less eco-harmful ways. Studies show that companies started gaining a reputation in the market through their eco-friendly activities in their business. Hence companies should be alert to understand the consumer's environmentally friendly consumption behavior to survive and be in the game of the competition. Green marketing efforts guarantee beneficial exchanges without harmful consequences for current and /or upcoming generations. This hits the green policies of those companies which are claiming environmental concern. This means that these companies not only focus on the impact of their production and products on the ecosystem but also on every small activity in their value chain. One of the most ignored parts of the value chain is the medium through which the marketing of products/services is done. These companies should also take into account to what degree their selection of advertising media affects the ecosystem of the earth. In this study, a hypothetical fashion apparel brand known as "Dolphin" will be studied. In particular, the following objectives are framed: i) to study the brand attitude of the given fashion brand due to its selection of eco-friendly advertising medium ii) to study the advertisement attitude of the given fashion brand due to its selection of eco-friendly advertising medium and iii) to study the purchase intention of the given fashion brand due to its selection of eco-friendly advertising medium. An online experiment will be conducted. Respondents between the ages of 20-and 64 years will be selected randomly from the online consumer panel database. The findings of this study will have a great impact on the companies that are claiming environmental concerns by understanding how the advertising media is affecting the company’s brand image in the long run.

Keywords: eco-friendly advertising media, fashion, attitude, purchase intention

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Authors: Sonia Kudlacik-Kramarczyk, Anna Drabczyk, Dagmara Malina, Bozena Tyliszczak, Agnieszka Sobczak-Kupiec

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Introduction: In the preparation of polymer materials, compounds of natural origin are currently gaining more and more interest. This is particularly noticeable in the case of synthesis of materials considered for biomedical use. Then, selected material has to meet many requirements. It should be characterized by non-toxicity, biodegradability and biocompatibility. Therefore special attention is directed to substances such as polysaccharides, proteins or substances that are the basic building components of proteins, i.e. amino acids. These compounds may be crosslinked with other reagents that leads to the preparation of polymer matrices. Such amino acids as e.g. cysteine or histidine. On the other hand, previously mentioned requirements may be met by polymers obtained as a result of biosynthesis, e.g. polyhydroxybutyrate. This polymer belongs to the group of aliphatic polyesters that is synthesized by microorganisms (selected strain of bacteria) under specific conditions. It is possible to modify matrices based on given polymer with substances of various origin. Such a modification may result in the change of their properties or/and in providing the material with new features desirable in viewpoint of specific application. Described materials are synthesized using UV radiation. Process of photopolymerization is fast, waste-free and enables to obtain final products with favorable properties. Methodology: Polymer matrices have been prepared by means of photopolymerization. First step involved the preparation of solutions of particular reagents and mixing them in the appropriate ratio. Next, crosslinking agent and photoinitiator have been added to the reaction mixture and the whole was poured into the Petri dish and treated with UV radiation. After the synthesis, polymer samples were dried at room temperature and subjected to the numerous analyses aimed at the determining their physicochemical properties. Firstly, sorption properties of obtained polymer matrices have been determined. Next, mechanical properties have been characterized, i.e. tensile strength. The ability to deformation under applied stress of all prepared polymer matrices has been checked. Such a property is important in viewpoint of the application of analyzed materials e.g. as wound dressings. Wound dressings have to be elastic because depending on the location of the wound and its mobility, such a dressing has to adhere properly to the wound. Furthermore, considering the use of the materials for biomedical purposes it is essential to determine its behavior in environments simulating these ones occurring in human body. Therefore incubation studies using selected liquids have also been conducted. Conclusions: As a result of photopolymerization process, polymer matrices based on natural compounds have been prepared. These exhibited favorable mechanical properties and swelling ability. Moreover, biocompatibility in relation to simulated body fluids has been stated. Therefore it can be concluded that analyzed polymer matrices constitute an interesting materials that may be considered for biomedical use and may be subjected to the further more advanced analyses using specific cell lines.

Keywords: photopolymerization, polymer matrices, simulated body fluids, swelling properties

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Authors: Boris Blostotsky, Elia Efraim

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The phenomenon of buckling of structural elements under compression is revealed in many cases of loading and found consideration in many structures and mechanisms. In the present work the method and results of dynamic test for buckling of bar loaded by a compression force directed towards the pole are considered. Experimental determination of critical force for such system has not been made previously. The tested object is a bar with semi-rigid connection to the base at one of its ends, and with a hinge moving along a circle at the other. The test includes measuring the natural frequency of the bar at different values of compression load. The lateral stiffness is calculated based on natural frequency and reduced mass on the bar's movable end. The critical load is determined by extrapolation the values of lateral stiffness up to zero value. For the experimental investigation the special test-bed was created that allows the stability testing at positive and negative curvature of the movable end's trajectory, as well as varying the rotational stiffness of the other end connection. Decreasing a friction at the movable end allows extend the diapason of applied compression force. The testing method includes: - Methodology of the experiment planning, that allows determine the required number of tests under various loads values in the defined range and the type of extrapolating function; - Methodology of experimental determination of reduced mass at the bar's movable end including its own mass; - Methodology of experimental determination of lateral stiffness of uncompressed bar rotational semi-rigid connection at the base. For planning the experiment and for comparison of the experimental results with the theoretical values of critical load, the analytical dependencies of lateral stiffness of the bar with defined end conditions on compression load. In the particular case of perfectly rigid connection of the bar to the base, the critical load value corresponds to solution by S.P. Timoshenko. Correspondence of the calculated and experimental values was obtained.

Keywords: non-destructive test, buckling, dynamic method, semi-rigid connections

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Authors: Taner Izzet Acarer, Ece Ceylan Baba

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This paper examines green building certification systems and their current processes in comparison with anticipatory systems. Rapid growth of human population and depletion of natural resources are causing irreparable damage to urban and natural environment. In this context, the concept of ‘sustainable architecture’ has emerged in the 20th century so as to establish and maintain standards for livable urban spaces, to improve quality of urban life, and to preserve natural resources for future generations. The construction industry is responsible for a large part of the resource consumption and it is believed that the ‘green building’ designs that emerge in construction industry can reduce environmental problems and contribute to sustainable development around the world. A building must meet a specific set of criteria, set forth through various certification systems, in order to be eligible for designation as a green building. It is disputable whether methods used by green building certification systems today truly serve the purposes of creating a sustainable world. Accordingly, this study will investigate the sets of rating systems used by the most popular green building certification programs, including LEED (Leadership in Energy and Environmental Design), BREEAM (Building Research Establishment's Environmental Assessment Methods), DGNB (Deutsche Gesellschaft für Nachhaltiges Bauen System), in terms of ‘Anticipatory Systems’ in accordance with the certification processes and their goals, while discussing their contribution to architecture. The basic methodology of the study is as follows. Firstly analyzes of brief historical and literature review of green buildings and certificate systems will be stated. Secondly, processes of green building certificate systems will be disputed by the help of anticipatory systems. Anticipatory Systems is a set of systems designed to generate action-oriented projections and to forecast potential side effects using the most current data. Anticipatory Systems pull the future into the present and take action based on future predictions. Although they do not have a claim to see into the future, they can provide foresight data. When shaping the foresight data, Anticipatory Systems use feedforward instead of feedback, enabling them to forecast the system’s behavior and potential side effects by establishing a correlation between the system’s present/past behavior and projected results. This study indicates the goals and current status of LEED, BREEAM and DGNB rating systems that created by using the feedback technique will be examined and presented in a chart. In addition, by examining these rating systems with the anticipatory system that using the feedforward method, the negative influences of the potential side effects on the purpose and current status of the rating systems will be shown in another chart. By comparing the two obtained data, the findings will be shown that rating systems are used for different goals than the purposes they are aiming for. In conclusion, the side effects of green building certification systems will be stated by using anticipatory system models.

Keywords: anticipatory systems, BREEAM, certificate systems, DGNB, green buildings, LEED

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Authors: Irfan Turetgen

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Closed-circuit cooling towers are cooling units that operate according to the indirect cooling principle. Unlike the open-loop cooling tower, the filler material includes a closed-loop water-operated heat exchanger. The main purpose of this heat exchanger is to prevent the cooled process water from contacting with the external environment. In order to ensure that the hot water is cooled, the water is cooled by the air flow and the circulation water of the tower as it passes through the pipe. They are now more commonly used than open loop cooling towers that provide cooling with plastic filling material. As with all surfaces in contact with water, there is a biofilm formation on the outer surface of the pipe. Although biofilm has been studied very well on plastic surfaces in open loop cooling towers, studies on biofilm layer formed on the heat exchangers of the closed circuit tower have not been found. In the recent study, natural biofilm formation was observed on the heat exchangers of the closed loop tower for 6 months. At the same time, nano-silica coating, which is known to reduce the formation of the biofilm layer, a comparison was made between the two different surfaces in terms of biofilm formation potential. Test surfaces were placed into biofilm reactor along with the untreated control coupons up to 6-months period for biofilm maturation. Natural bacterial communities were monitored to analyze the impact to mimic the real-life conditions. Surfaces were monthly analyzed in situ for their microbial load using epifluorescence microscopy. Wettability is known to play a key role in biofilm formation on surfaces, because characteristics of surface properties affect the bacterial adhesion. Results showed that surface-conditioning with nano-silica significantly reduce (up to 90%) biofilm formation. Easy coating process is a facile and low-cost method to prepare hydrophobic surface without any kinds of expensive compounds or methods.

Keywords: biofilms, cooling towers, fill material, nano silica

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Authors: Netanel Stern

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Artificial intelligence (AI) algorithms have emerged as powerful tools in the field of psychiatry, offering new possibilities for enhancing diagnosis and treatment outcomes. This article explores the utilization of AI algorithms in psychiatry, highlighting their potential to revolutionize patient care. Various AI algorithms, including machine learning, natural language processing (NLP), reinforcement learning, clustering, and Bayesian networks, are discussed in detail. Moreover, ethical considerations and future directions for research and implementation are addressed.

Keywords: AI, software engineering, psychiatry, neuroimaging

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Authors: Hye-Young Shin, Chan Kee Park

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Background: To compare the thinning patterns of the ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) as measured using Cirrus high-definition optical coherence tomography (HD-OCT) in patients with visual field (VF) defects that respect the vertical meridian. Methods: Twenty eyes of eleven patients with VF defects that respect the vertical meridian were enrolled retrospectively. The thicknesses of the macular GCIPL and pRNFL were measured using Cirrus HD-OCT. The 5% and 1% thinning area index (TAI) was calculated as the proportion of abnormally thin sectors at the 5% and 1% probability level within the area corresponding to the affected VF. The 5% and 1% TAI were compared between the GCIPL and pRNFL measurements. Results: The color-coded GCIPL deviation map showed a characteristic vertical thinning pattern of the GCIPL, which is also seen in the VF of patients with brain lesions. The 5% and 1% TAI were significantly higher in the GCIPL measurements than in the pRNFL measurements (all P < 0.01). Conclusions: Macular GCIPL analysis clearly visualized a characteristic topographic pattern of retinal ganglion cell (RGC) loss in patients with VF defects that respect the vertical meridian, unlike pRNFL measurements. Macular GCIPL measurements provide more valuable information than pRNFL measurements for detecting the loss of RGCs in patients with retrograde degeneration of the optic nerve fibers.

Keywords: brain lesion, macular ganglion cell, inner plexiform layer, spectral-domain optical coherence tomography

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Authors: Mahan Qwamizadeh, Kun Zhou, Zuoqi Zhang, Yong Wei Zhang

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Typical load-bearing biological materials like bone, mineralized tendon and shell, are biocomposites made from both organic (collagen) and inorganic (biomineral) materials. This amazing class of materials with intrinsic internally designed hierarchical structures show superior mechanical properties with regard to their weak components from which they are formed. Extensive investigations concentrating on static loading conditions have been done to study the biological materials failure. However, most of the damage and failure mechanisms in load-bearing biological materials will occur whenever their structures are exposed to dynamic loading conditions. The main question needed to be answered here is: What is the relation between the layout and architecture of the load-bearing biological materials and their dynamic behavior? In this work, a staggered model has been developed based on the structure of natural materials at nanoscale and Finite Element Analysis (FEA) has been used to study the dynamic behavior of the structure of load-bearing biological materials to answer why the staggered arrangement has been selected by nature to make the nanocomposite structure of most of the biological materials. The results showed that the staggered structures will efficiently attenuate the stress wave rather than the layered structure. Furthermore, such staggered architecture is effectively in charge of utilizing the capacity of the biostructure to resist both normal and shear loads. In this work, the geometrical parameters of the model like the thickness and aspect ratio of the mineral inclusions selected from the typical range of the experimentally observed feature sizes and layout dimensions of the biological materials such as bone and mineralized tendon. Furthermore, the numerical results validated with existing theoretical solutions. Findings of the present work emphasize on the significant effects of dynamic behavior on the natural evolution of load-bearing biological materials and can help scientists to design bioinspired materials in the laboratories.

Keywords: load-bearing biological materials, nanostructure, staggered structure, stress wave decay

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Authors: C. Mazilu, D. P. Georgescu, A. Apostu, R. Deju

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Cement mortars and concretes are some of the most used construction materials in the world, global cement production being expected to grow to approx. 5 billion tons, until 2030. But, cement is an energy intensive material, the cement industry being responsible for cca. 7% of the world's CO2 emissions. Also, natural aggregates represent non-renewable resources, exhaustible, which must be used efficiently. A way to reduce the negative impact on the environment is the use of additional hydraulically active materials, as a partial substitute for cement in mortars and concretes and/or the use of recycled concrete aggregates (RCA) for the recovery of construction waste, according to EU Directive 2018/851. One of the most effective active hydraulic admixtures is microsilica and more recently, with the technological development on a nanometric scale, nanosilica. Studies carried out in recent years have shown that the introduction of SiO2 nanoparticles into cement matrix improves the properties, even compared to microsilica. This is due to the very small size of the nanosilica particles (<100nm) and the very large specific surface, which helps to accelerate cement hydration and acts as a nucleating agent to generate even more calcium hydrosilicate which densifies and compacts the structure. The cementitious compositions containing recycled concrete aggregates (RCA) present, in generally, inferior properties compared to those obtained with natural aggregates. Depending on the degree of replacement of natural aggregate, decreases the workability of mortars and concretes with RAC, decrease mechanical resistances and increase drying shrinkage; all being determined, in particular, by the presence to the old mortar attached to the original aggregate from the RAC, which makes its porosity high and the mixture of components to require more water for preparation. The present study aims to use micro and nanosilica for increase the performance of some mortars and concretes obtained with RCA. The research focused on two types of cementitious systems: a special mortar composition used for encapsulating Low Level radioactive Waste (LLW); a composition of structural concrete, class C30/37, with the combination of exposure classes XC4+XF1 and settlement class S4. The mortar was made with 100% recycled aggregate, 0-5 mm sort and in the case of concrete, 30% recycled aggregate was used for 4-8 and 8-16 sorts, according to EN 206, Annex E. The recycled aggregate was obtained from a specially made concrete for this study, which after 28 days was crushed with the help of a Retsch jaw crusher and further separated by sieving on granulometric sorters. The partial replacement of cement was done progressively, in the case of the mortar composition, with microsilica (3, 6, 9, 12, 15% wt.), nanosilica (0.75, 1.5, 2.25% wt.), respectively mixtures of micro and nanosilica. The optimal combination of silica, from the point of view of mechanical resistance, was later used also in the case of the concrete composition. For the chosen cementitious compositions, the influence of micro and/or nanosilica on the properties in the fresh state (workability, rheological characteristics) and hardened state (mechanical resistance, water absorption, freeze-thaw resistance, etc.) is highlighted.

Keywords: cement, recycled concrete aggregates, micro/nanosilica, durability

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Authors: Emely J. Escala, Lolito C. Bestil

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An experiment was conducted to assess the potential of jackfruit by-product concentrate (JBC) in combination with two types of protein sources, soybean meal (SBM) and liquid acid whey (LAW), given at two different ratios as supplement for growing kids fed a basal diet of 70:30 napier grass (Pennisetum purpureum) and kakawate (Gliricidia sepium) soilage ratio. The experiment was set-up in randomized complete block design (RCBD) with sex-age combination as basis for blocking, with the following dietary treatments: T1 = 0.50:0.50% BW, DM basis, JBC:SBM, T2 = 0.75:0.25% BW JBC:SBM, T3 = 0.50:0.50% BW, DM basis, JBC:LAW, and T4 = 0.75:0.25% BW JBC:LAW. Analysis of JBC showed high contents of crude fiber with medium levels of crude protein and nitrogen-free extract, appearing to be fitting for ruminants and a potential energy source. Results showed significantly higher voluntary dry matter intake (VDMI), cumulative weight gain (CWG), and average daily gain (ADG) of growing goats supplemented with JBC in combination with SBM than with LAW. The amount of JBC can range from 0.50% to 0.75% BW with SBM making up the difference, but a JBC:SBM ratio of 0.75:0.25% BW, DM basis, is best in promoting highest voluntary dry matter intake and is, therefore, highly recommended in the light of savings in feed cost. A long-term study on the effects of JBC supplementation on meat qualities of growing kids (aroma, marbling characteristics and taste) is also recommended.

Keywords: jackfruit by-product concentrate, liquid acid whey, soybean meal, grower kids

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Authors: Şevket Evci, Mehmet Akif Karsli

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The aim of this study is to determine nutrient contents, in situ ruminal degradation kinetics and protein fractions of screenings bean (B), chick pea (ChP), red lentil (RL) and green lentil (GL) that is used as residue in grain legume packing industry. For this purpose, four samples of each legumes species-a total of 16 samples, collected from different parts of our country were utilized. Feedstuffs used in the experiment were incubated for 0, 2 4, 8, 12, 24, and 48 hours in the rumen of 3 ruminally cannulated Akkaraman rams as duplicate. The nutrient contents, in situ ruminal dry matter (DM), organic matter (OM) and crude protein (CP) degradabilities and fractions, and escape protein contents were evaluated. The highest OM and CP contents were observed in RL (P<0.05). Chick pea had the highest ether extract (EE) content and EE values were 3.47, 6.72, 2.26, 8.66 % for RL, B, GL and ChP, respectively (P<0.05). Crude fiber (CF), ADF, and NDF contents were the highest in RL and the lowest in ChP. CF values were 24.03, 10.80, 4.09 and 3.57 % for RL, GL, B and ChP (P<0.05). Acid detergent insoluble nitrogen content of samples did not differ. Escape protein content was the highest in RL and the lowest in B (P<0.05). After 48 h incubation, the lowest OM and CP degradabilities were observed in RL. While the highest OM degradability was seen in ChP the highest CP degradability was observed in B (P<0.05). The lowest water soluble OM and CP contents were observed in RL whereas the highest potentially degradable OM and CP contents were seen in B and ChP (P<0.05). Both rate of OM and CP degradations (k-1) did not differ among samples (P>0.05). In conclusion, it was noted that feedstuffs (GL, ChP and B) used in the experiment except RL had a greater ruminal degradibilities of both OM and CP and moreover, had a higher escape protein contents, except B. It was thought that these feedstuffs can be substituted with some of common protein sources used in animal nutrition.

Keywords: in situ, nutrient contents, ruminant, subsieve

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Authors: Azize Serap Tuncer

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Turkey is one of the most outstanding figures among the Mediterranean countries from the natural and historical point at view. It is relatively rich country as regards the flora and vegetation. But at the same time as a result of improper and unplanned usage of the land for centuries, its forests and fertile soils have been exposed to great damages. While rapid and uncontrolled urbanization has important effects on the environment, urban development legislations, have become very unsufficient for the protection of these areas. Some of them have been completely eradicated, and some others have lost their fertility. Besides Turkey has a high main land with a rough surface and its soils areas exposed to heavy erosion. On the other hand as a developing country, it is not willing to endanger the goals of industrialization and avoid foreign direct investment by implementing strict environmental policies. Although this kind of pressure on forestland resources threatens the stability of forest land and land use management, in recent years, there has been an obvious increase in public concern about environmental problems like over global warming, environmental pollution, deforestation and their potential effects on natural resources. To protect the ecological balance and prevention of naturel resources from the unplanned intervention of human-beıng is only possible establishing conservation areas wıth co-operation at the national and the internatıonal levels. This study was carried out to evaluate the relation between urbanization and forestry policies in Turkey. While it elaborates the normative arrangements resulting in power conflicts, it also addresses which shortages and discrepancies are responsible for the said conflicts. The present urban reconstruction and transformation practices and their aesthetic and functional aspects were studied with some examples in a country level and evaluated within the assistance of literature researches, analyses, and observations. Atatürk Forest Farm and ODTU Forest examples were negotiated as two famous cases. Obtained findings were supported by charts and photos.

Keywords: deforestration, environmental policies, metropolitan, pollution, urbanization

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Authors: Abdullah Alenezi, Mane Alsudrawi, Rafat Misak

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Kuwait is faced with a potentially wide and harmful range of both natural and anthropogenic hazardous events such as dust storms, floods, fires, nuclear accidents, earthquakes, oil spills, tsunamis and other disasters. For Kuwait can be highly vulnerable to these complex environmental risks, an up-to-date and in-depth understanding of their typology, genesis, and impact on the Kuwaiti society is needed. Adequate anticipation and management of environmental crises further require a comprehensive system of decision support to the benefit of decision makers to further bridge the gap between (technical) risk understanding and public action. For that purpose, the Kuwait Institute for Scientific Research (KISR), intends to establish a decision support center for management of the environmental crisis in Kuwait. The center will support policy makers, stakeholders and national committees with technical information that helps them efficiently and effectively assess, monitor to manage environmental disasters using decision support tools. These tools will build on state of the art quantification and visualization techniques, such as remote sensing information, Geographical Information Systems (GIS), simulation and prediction models, early warning systems, etc. The center is conceived as a central facility which will be designed, operated and managed by KISR in coordination with national authorities and decision makers of the country. Our vision is that by 2035 the center will be recognized as a leading national source of scientific advice on national risk management in Kuwait and build unity of effort among Kuwaiti’s institutions, government agencies, public and private organizations through provision and sharing of information. The project team now focuses on capacity building through upgrading some KISR facilities manpower development, build strong collaboration with international alliance.

Keywords: decision support, environment, hazard, Kuwait

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Authors: Viriyavudh Sim, SeungHyun Kim, JungKyu Choi, WooYoung Jung

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Glass Fiber Reinforced Polymer (GFRP) is a major evolution for energy dissipation when used as infill material for seismic retrofitting of steel frame, a basic PMC infill wall system consists of two GFRP laminates surrounding an infill of foam core. This paper presents numerical analysis in terms of buckling resistance of GFRP sandwich infill panels system under the influence of environment temperature and stacking sequence of laminate skin. Mode of failure under in-plane compression is studied by means of numerical analysis with ABAQUS platform. Parameters considered in this study are contact length between infill and frame, laminate stacking sequence of GFRP skin and variation of mechanical properties due to increment of temperature. The analysis is done with four cases of simple stacking sequence over a range of temperature. The result showed that both the effect of temperature and stacking sequence alter the performance of entire panel system. The rises of temperature resulted in the decrements of the panel’s strength. This is due to the polymeric nature of this material. Additionally, the contact length also displays the effect on the performance of infill panel. Furthermore, the laminate stiffness can be modified by orientation of laminate, which can increase the infill panel strength. Hence, optimal performance of the entire panel system can be obtained by comparing different cases of stacking sequence.

Keywords: buckling resistance, GFRP infill panel, stacking sequence, temperature dependent

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Authors: Gregor Kosec

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Simple and robust numerical approach for solving flow problems is presented, where involved physical fields are represented through the local approximation functions, i.e., the considered field is approximated over a local support domain. The approximation functions are then used to evaluate the partial differential operators. The type of approximation, the size of support domain, and the type and number of basis function can be general. The solution procedure is formulated completely through local computational operations. Besides local numerical method also the pressure velocity is performed locally with retaining the correct temporal transient. The complete locality of the introduced numerical scheme has several beneficial effects. One of the most attractive is the simplicity since it could be understood as a generalized Finite Differences Method, however, much more powerful. Presented methodology offers many possibilities for treating challenging cases, e.g. nodal adaptivity to address regions with sharp discontinuities or p-adaptivity to treat obscure anomalies in physical field. The stability versus computation complexity and accuracy can be regulated by changing number of support nodes, etc. All these features can be controlled on the fly during the simulation. The presented methodology is relatively simple to understand and implement, which makes it potentially powerful tool for engineering simulations. Besides simplicity and straightforward implementation, there are many opportunities to fully exploit modern computer architectures through different parallel computing strategies. The performance of the method is presented on the lid driven cavity problem, backward facing step problem, de Vahl Davis natural convection test, extended also to low Prandtl fluid and Darcy porous flow. Results are presented in terms of velocity profiles, convergence plots, and stability analyses. Results of all cases are also compared against published data.

Keywords: fluid flow, meshless, low Pr problem, natural convection

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Authors: Hannah S. Elizabeth, D. Gnanasekaran, M. R. Manju Gowda, Antony George

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Phytoremediation a new technology of remediating the contaminated soil, water and air using plants and serves as a green technology with environmental friendly approach. The main aim of this technique is cleansing and detoxifying of organic compounds, organo-phosphorous pesticides, heavy metals like arsenic, iron, cadmium, gold, radioactive elements which cause teratogenic and life threatening diseases to mankind and animal kingdom when consume the food crops, vegetables, fruits, cerals, and millets obtained from the contaminated soil. Also, directly they may damage the genetic materials thereby alters the biosynthetic pathways of secondary metabolites and other phytoconstituents which may have different pharmacological activities which lead to lost their efficacy and potency as well. It would reflect in mutagenicity, drug resistance and affect other antagonistic properties of normal metabolism. Is the technology for real clean-up of contaminated soils and the contaminants which are potentially toxic. It reduces the risks produced by a contaminated soil by decreasing contaminants using plants as a source. The advantages are cost-effectiveness and less ecosystem disruption. Plants may also help to stabilize contaminants by accumulating and precipitating toxic trace elements in the roots. Organic pollutants can potentially be chemically degraded and ultimately mineralized into harmless biological compounds. Hence, the use of plants to revitalize contaminated sites is gaining more attention and preferred for its cost-effective when compared to other chemical methods. The introduction of harmful substances into the environment has been shown to have many adverse effects on human health, agricultural productivity, and natural ecosystems. Because the costs of growing a crop are minimal compared to those of soil removal and replacement, the use of plants to remediate hazardous soils is seen as having great promise.

Keywords: cost effective, eco-friendly, phytoremediation, secondary metabolites

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Authors: Juan José Mesas, Luis Sainz

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The motivation for the development of this paper lies in the need for energy networks to reduce losses, improve performance, optimize their operation and try to benefit from the interconnection capacity with other networks enabled for other energy carriers. These interconnections generate interdependencies between some energy networks and others, which requires suitable models and methods for their analysis. Traditionally, the modeling and study of energy networks have been carried out independently for each energy carrier. Thus, there are well-established models and methods for the steady-state analysis of electrical networks, gas networks, and thermal networks separately. What is intended is to extend and combine them adequately to be able to face in an integrated way the steady-state analysis of networks with multiple energy carriers. Firstly, the added value of multi-energy networks, their operation, and the basic principles that characterize them are explained. In addition, two current aspects of great relevance are exposed: the storage technologies and the coupling elements used to interconnect one energy network with another. Secondly, the characteristic equations of the different energy networks necessary to carry out the steady-state analysis are detailed. The electrical network, the natural gas network, and the thermal network of heat and cold are considered in this paper. After the presentation of the equations, a particular case of the steady-state analysis of a specific multi-energy network is studied. This network is represented graphically, the interconnections between the different energy carriers are described, their technical data are exposed and the equations that have previously been presented theoretically are formulated and developed. Finally, the two iterative numerical resolution methods considered in this paper are presented, as well as the resolution procedure and the results obtained. The pros and cons of the application of both methods are explained. It is verified that the results obtained for the electrical network (voltages in modulus and angle), the natural gas network (pressures), and the thermal network (mass flows and temperatures) are correct since they comply with the distribution, operation, consumption and technical characteristics of the multi-energy network under study.

Keywords: coupling elements, energy carriers, multi-energy networks, steady-state analysis

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