Search results for: modern code
1094 Raman, Atomic Force Microscopy and Mass Spectrometry for Isotopic Ratios Methods Used to Investigate Human Dentine and Enamel
Authors: Nicoleta Simona Vedeanu, Rares Stiufiuc, Dana Alina Magdas
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A detailed knowledge of the teeth structure is mandatory to understand and explain the defects and the dental pathology, but especially to take a correct decision regarding dental prophylaxis and treatment. The present work is an alternative study to the traditional investigation methods used in dentistry, a study based on the use of modern, sensitive physical methods to investigate human enamel and dentin. For the present study, several teeth collected from patients of different ages were used for structural and dietary investigation. The samples were investigated by Raman spectroscopy for the molecular structure analysis of dentin and enamel, atomic force microscopy (AFM) to view the dental topography at the micrometric size and mass spectrometry for isotopic ratios as a fingerprint of patients’ personal diet. The obtained Raman spectra and their interpretation are in good correlation with the literature and may give medical information by comparing affected dental structures with healthy ones. AFM technique gave us the possibility to study in details the dentin and enamel surface to collect information about dental hardness or dental structural changes. δ¹³C values obtained for the studied samples can be classified in C4 category specific to young people and children diet (sweets, cereals, juices, pastry). The methods used in this attempt furnished important information about dentin and enamel structure and dietary habits and each of the three proposed methods can be extended at a larger level in the study of the teeth structure.Keywords: AFM, dentine, enamel, Raman spectroscopy
Procedia PDF Downloads 1451093 Atom Probe Study of Early Stage of Precipitation on Binary Al-Li, Al-Cu Alloys and Ternary Al-Li-Cu Alloys
Authors: Muna Khushaim
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Aluminum-based alloys play a key role in modern engineering, especially in the aerospace industry. Introduction of solute atoms such as Li and Cu is the main approach to improve the strength in age-hardenable Al alloys via the precipitation hardening phenomenon. Knowledge of the decomposition process of the microstructure during the precipitation reaction is particularly important for future technical developments. The objective of this study is to investigate the nano-scale chemical composition in the Al-Cu, Al-Li and Al-Li-Cu during the early stage of the precipitation sequence and to describe whether this compositional difference correlates with variations in the observed precipitation kinetics. Comparing the random binomial frequency distribution and the experimental frequency distribution of concentrations in atom probe tomography data was used to investigate the early stage of decomposition in the different binary and ternary alloys which were experienced different heat treatments. The results show that an Al-1.7 at.% Cu alloy requires a long ageing time of approximately 8 h at 160 °C to allow the diffusion of Cu atoms into Al matrix. For the Al-8.2 at.% Li alloy, a combination of both the natural ageing condition (48 h at room temperature) and a short artificial ageing condition (5 min at 160 °C) induces increasing on the number density of the Li clusters and hence increase number of precipitated δ' particles. Applying this combination of natural ageing and short artificial ageing conditions onto the ternary Al-4 at.% Li-1.7 at.% Cu alloy induces the formation of a Cu-rich phase. Increasing the Li content in the ternary alloy up to 8 at.% and increasing the ageing time to 30 min resulted in the precipitation processes ending with δ' particles. Thus, the results contribute to the understanding of Al-alloy design.Keywords: aluminum alloy, atom probe tomography, early stage, decomposition
Procedia PDF Downloads 3431092 Women's Employment Issues in Georgia and Solutions Based on European Experience
Authors: N. Damenia, E. Kharaishvili, N. Sagareishvili, M. Saghareishvili
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Women's Employment is one of the most important issues in the global economy. The article discusses the stated topic in Georgia, through historical content, Soviet experience, and modern perspectives. The paper discusses segmentation insa terms of employment and related problems. Based on statistical analysis, women's unemployment rate and its factors are analyzed. The level of employment of women in Transcaucasia (Georgia, Armenia, and Azerbaijan) is discussed and is compared with Baltic countries (Lithuania, Latvia, and Estonia). The study analyzes women’s level of development, according to the average age of marriage and migration level. The focus is on Georgia's Association Agreement with the EU in 2014, which includes economic, social, trade and political issues. One part of it is gender equality at workplaces. According to the research, the average monthly remuneration of women managers in the financial and insurance sector equaled to 1044.6 Georgian Lari, while in overall business sector average monthly remuneration equaled to 961.1 GEL. Average salaries are increasing; however, the employment rate remains problematic. For example, in 2017, 74.6% of men and 50.8% of women were employed from a total workforce. It is also interesting that the proportion of men and women at managerial positions is 29% (women) to 71% (men). Based on the results, the main recommendation for government and civil society is to consider women as a part of the country’s economic development. In this aspect, the experience of developed countries should be considered. It is important to create additional jobs in urban or rural areas and help migrant women return and use their working resources properly.Keywords: employment of women, segregation in terms of employment, women's employment level in Transcaucasia, migration level
Procedia PDF Downloads 1171091 Solar PV System for Automatic Guideway Transit (AGT) System in BPSU Main Campus
Authors: Nelson S. Andres, Robert O. Aguilar, Mar O. Tapia, Meeko C. Masangcap, John Denver Catapang, Greg C. Mallari
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This study focuses on exploring the possibility of using solar PV as an alternative for generating electricity to electrify the AGT System installed in BPSU Main Campus instead of using the power grid. The output of this study gives BPSU the option to invest on solar PV system to pro-actively respond to one of UN’s Sustainable Development Goals of having reliable, sustainable and modern energy sources to reduce energy pollution and climate change impact in the long run. Thus, this study covers the technical as well as the financial studies, which BPSU can also be used to outsource funding from different government agencies. For this study, the electrical design and requirements of the on-going DOST AGT system project are carefully considered. In the proposed design, the AGT station has installed with a rechargeable battery system where the energy harnessed by the solar PV panels installed on the rooftop of the station/NCEA building shall be directed to. The solar energy is then directly supplied to the electric double-layer capacitors (EDLC's) batteries and thus transmitted to other types of equipment in need. When the AGT is not in use, the harnessed energy may be used by NCEA building, thus, lessening the energy consumption of the building from the grid. The use of solar PV system with EDLC is compared with the use of an electric grid for the purpose of electrifying the AGT or the NCEA building (when AGT is not in use). This is to figure how much solar energy are accumulated by the solar PV to accommodate the need for coaches’ motors, lighting, air-conditioning units, door sensor, panel display, etc. The proposed PV Solar design, as well as the data regarding the charging and discharging of batteries and the power consumption of all AGT components, are simulated for optimization, analysis and validation through the use of PVSyst software.Keywords: AGT, Solar PV, railway, EDLC
Procedia PDF Downloads 821090 Computational Investigation of Secondary Flow Losses in Linear Turbine Cascade by Modified Leading Edge Fence
Authors: K. N. Kiran, S. Anish
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It is well known that secondary flow loses account about one third of the total loss in any axial turbine. Modern gas turbine height is smaller and have longer chord length, which might lead to increase in secondary flow. In order to improve the efficiency of the turbine, it is important to understand the behavior of secondary flow and device mechanisms to curtail these losses. The objective of the present work is to understand the effect of a stream wise end-wall fence on the aerodynamics of a linear turbine cascade. The study is carried out computationally by using commercial software ANSYS CFX. The effect of end-wall on the flow field are calculated based on RANS simulation by using SST transition turbulence model. Durham cascade which is similar to high-pressure axial flow turbine for simulation is used. The aim of fencing in blade passage is to get the maximum benefit from flow deviation and destroying the passage vortex in terms of loss reduction. It is observed that, for the present analysis, fence in the blade passage helps reducing the strength of horseshoe vortex and is capable of restraining the flow along the blade passage. Fence in the blade passage helps in reducing the under turning by 70 in comparison with base case. Fence on end-wall is effective in preventing the movement of pressure side leg of horseshoe vortex and helps in breaking the passage vortex. Computations are carried for different fence height whose curvature is different from the blade camber. The optimum fence geometry and location reduces the loss coefficient by 15.6% in comparison with base case.Keywords: boundary layer fence, horseshoe vortex, linear cascade, passage vortex, secondary flow
Procedia PDF Downloads 3491089 Endoscopic Treatment of Esophageal Injuries Using Vacuum Therapy
Authors: Murad Gasanov, Shagen Danielyan, Ali Gasanov, Yuri Teterin, Peter Yartsev
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Background: Despite the advances made in modern surgery, the treatment of patients with esophageal injuries remains one of the most topical and complex issues. In recent years, high-technology minimally invasive methods, such as endoscopic vacuum therapy (EVT) in the treatment of esophageal injuries. The effectiveness of EVT has been sufficiently studied in case of failure of esophageal anastomoses, however the application of this method in case of mechanical esophageal injuries is limited by a small series of observations, indicating the necessity of additional study. Aim: The aim was to аnalyzed of own experience in the use of endoscopic vacuum therapy (EVT) in a comprehensive examination of patients with esophageal injuries. Methods: We analyzed the results of treatment of 24 patients with mechanical injuries of the esophagus for the period 2019-2021. Complex treatment of patients included the use of minimally invasive technologies, including percutaneous endoscopic gastrostomy (PEG), EVT and video-assisted thoracoscopic debridement. Evaluation of the effectiveness of treatment was carried out using multislice computed tomography (MSCT), endoscopy and laboratory tests. The duration of inpatient treatment and the duration of EVT, the number of system replacements, complications and mortality were taken into account. Result: EVT in patients with mechanical injuries of the esophagus allowed to achieve epithelialization of the esophageal defect in 21 patients (87.5%) in the form of linear scar on the site of perforation or pseudodiverticulum. Complications were noted in 4 patients (16.6%), including bleeding (2) and and esophageal stenosis in the perforation area (2). Lethal outcome was in one observation (4.2%). Conclusion. EVT may be the method of choice in complex treatment in patients with esophageal lesions.Keywords: esophagus injuries, damage to the esophagus, perforation of the esophagus, spontaneous perforation of the esophagus, mediastinitis, endoscopic vacuum therapy
Procedia PDF Downloads 1071088 An Extended Domain-Specific Modeling Language for Marine Observatory Relying on Enterprise Architecture
Authors: Charbel Aoun, Loic Lagadec
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A Sensor Network (SN) is considered as an operation of two phases: (1) the observation/measuring, which means the accumulation of the gathered data at each sensor node; (2) transferring the collected data to some processing center (e.g., Fusion Servers) within the SN. Therefore, an underwater sensor network can be defined as a sensor network deployed underwater that monitors underwater activity. The deployed sensors, such as Hydrophones, are responsible for registering underwater activity and transferring it to more advanced components. The process of data exchange between the aforementioned components perfectly defines the Marine Observatory (MO) concept which provides information on ocean state, phenomena and processes. The first step towards the implementation of this concept is defining the environmental constraints and the required tools and components (Marine Cables, Smart Sensors, Data Fusion Server, etc). The logical and physical components that are used in these observatories perform some critical functions such as the localization of underwater moving objects. These functions can be orchestrated with other services (e.g. military or civilian reaction). In this paper, we present an extension to our MO meta-model that is used to generate a design tool (ArchiMO). We propose new constraints to be taken into consideration at design time. We illustrate our proposal with an example from the MO domain. Additionally, we generate the corresponding simulation code using our self-developed domain-specific model compiler. On the one hand, this illustrates our approach in relying on Enterprise Architecture (EA) framework that respects: multiple views, perspectives of stakeholders, and domain specificity. On the other hand, it helps reducing both complexity and time spent in design activity, while preventing from design modeling errors during porting this activity in the MO domain. As conclusion, this work aims to demonstrate that we can improve the design activity of complex system based on the use of MDE technologies and a domain-specific modeling language with the associated tooling. The major improvement is to provide an early validation step via models and simulation approach to consolidate the system design.Keywords: smart sensors, data fusion, distributed fusion architecture, sensor networks, domain specific modeling language, enterprise architecture, underwater moving object, localization, marine observatory, NS-3, IMS
Procedia PDF Downloads 1771087 The Effect of Shredded Polyurethane Foams on Shear Modulus and Damping Ratio of Sand
Authors: Javad Saeidaskari, Nader Khalafian
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The undesirable impact of vibrations induced by road and railway traffic is an important concern in modern world. These vibrations are transmitted through soil and cause disturbances to the residence area and high-tech production facilities alongside the train/traffic lines. In this paper for the first time a new method of soil improvement with vibration absorber material, is used to increase the damping factor, in other word, to reduce the ability of wave transitions in sand. In this study standard Firoozkooh No. 161 sand is used as the host sand. The semi rigid polyurethane (PU) foam which used in this research is one of the common materials for vibration absorbing purposes. Series of cyclic triaxial tests were conducted on remolded samples with identical relative density of 70% of maximum dry density for different volume percentage of shredded PU foam. The frequency of tests was 0.1 Htz with shear strain of 0.37% and 0.75% and also the effective confining pressures during the tests were 100 kPa and 350 kPa. In order to find out the best soil-PU foam mixture, different volume percent of PU foam varying from 10% to 30% were examined. The results show that adding PU foam up to 20%, as its optimum content, causes notable enhancement in damping ratio for both shear strains of 0.37% (52.19% and 69% increase for effective confining pressures of 100 kPa and 350 kPa, respectively) and 0.75% (59.56% and 59.11% increase for effective confining pressures of 100 kPa and 350 kPa, respectively). The results related to shear modulus present significant reduction for both shear strains of 0.37% (82.22% and 56.03% decrease for effective confining pressures of 100 kPa and 350 kPa, respectively) and 0.75% (89.32% and 39.9% decrease for effective confining pressures of 100 kPa and 350 kPa, respectively). In conclusion, shredded PU foams effectively affect the dynamic properties of sand and act as vibration absorber in soil.Keywords: polyurethane foam, sand, damping ratio, shear modulus
Procedia PDF Downloads 4491086 A City Adapting to the Mobile Government and Hybrid Culture Established by Khitan-Liao (907-1125): Up-Capital (Shangjing) and its Special Tent Zone
Authors: Robin Ruowei Yang
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The Khitan-Liao dynasty (907-1125) was founded by the nomadic Khitan people and showed its peculiarities. This regime not only effectively ruled their own nomads, but also ruled the farming ethnic groups of the Han (漢) and others. It also controlled vast territories that included the northern border domains of China, East Asia, and even Central Asia. Different from the practice of other nomadic people, Khitan-Liao built settlement towns and cities on the Mongolia steppe from beginning of the dynasty, which made the politics, economy and culture of the steppe area develop significantly. In the process of cities’ construction, Khitan-Liao set up five capitals respectively. Except three of them were rebuilt or expanded based on existing cities in agricultural areas, two new capitals were built, namely up-capital (Shangjing) and middle-capital (Zhongjing) in the steppe area. This article takes the up-capital (Shangjing) as an example to investigate a special zone in the capital for settling movable tents which adapted Khitan nomads, especially its nomadic government officials to live in. By using primary Chinese historical records and newly archaeological excavations, this article examines how the special tent zone used by the Khitan rulers, discusses how the Khitan-Liao manifested its hybrid cultural characteristics in urban planning, and its implications in studying the history of Khitan-Liao. The information, discussion and argument presented in this article are also worth considering the influence of urbanization of Khitan-Liao’s urbaization on subsequent dynasties in pre-modern China and Inner Asia.Keywords: cities on Steppe, special tent zone in cities, Khitan-Liao, hybrid culture
Procedia PDF Downloads 801085 An Investigation into the Impacts of High-Frequency Electromagnetic Fields Utilized in the 5G Technology on Insects
Authors: Veriko Jeladze, Besarion Partsvania, Levan Shoshiashvili
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This paper addresses a very topical issue today. The frequency range 2.5-100 GHz contains frequencies that have already been used or will be used in modern 5G technologies. The wavelengths used in 5G systems will be close to the body dimensions of small size biological objects, particularly insects. Because the body and body parts dimensions of insects at these frequencies are comparable with the wavelength, the high absorption of EMF energy in the body tissues can occur(body resonance) and therefore can cause harmful effects, possibly the extinction of some of them. An investigation into the impact of radio-frequency nonionizing electromagnetic field (EMF) utilized in the future 5G on insects is of great importance as a very high number of 5G network components will increase the total EMF exposure in the environment. All ecosystems of the earth are interconnected. If one component of an ecosystem is disrupted, the whole system will be affected (which could cause cascading effects). The study of these problems is an important challenge for scientists today because the existing studies are incomplete and insufficient. Consequently, the purpose of this proposed research is to investigate the possible hazardous impact of RF-EMFs (including 5G EMFs) on insects. The project will study the effects of these EMFs on various insects that have different body sizes through computer modeling at frequencies from 2.5 to 100 GHz. The selected insects are honey bee, wasp, and ladybug. For this purpose, the detailed 3D discrete models of insects are created for EM and thermal modeling through FDTD and will be evaluated whole-body Specific Absorption Rates (SAR) at selected frequencies. All these studies represent a novelty. The proposed study will promote new investigations about the bio-effects of 5G-EMFs and will contribute to the harmonization of safe exposure levels and frequencies of 5G-EMFs'.Keywords: electromagnetic field, insect, FDTD, specific absorption rate (SAR)
Procedia PDF Downloads 911084 Entrepreneurship in Pakistan: Opportunities and Challenges
Authors: Bushra Jamil, Nudrat Baqri, Muhammad Hassan Saeed
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Entrepreneurship is creating or setting up a business not only for the purpose of generating profit but also for providing job opportunities. Entrepreneurs are problem solvers and product developers. They use their financial asset for hiring a professional team and combine the innovation, knowledge, and leadership leads to a successful startup or a business. To be a successful entrepreneur, one should be people-oriented and have perseverance. One must have the ability to take risk, believe in his/her potential, and have the courage to move forward in all circumstances. Most importantly, have the ability to take risk and can assess the risk. For STEM students, entrepreneurship is of specific importance and relevance as it helps them not just to be able to solve real life existing complications but to be able to recognize and identify emerging needs and glitches. It is becoming increasingly apparent that in today’s world, there is a need as well as a desire for STEM and entrepreneurship to work together. In Pakistan, entrepreneurship is slowly emerging, yet we are far behind. It is high time that we should introduce modern teaching methods and inculcate entrepreneurial initiative in students. A course on entrepreneurship can be included in the syllabus, and we must invite businessmen and policy makers to motivate young minds for entrepreneurship. This must be pitching competitions, opportunities to win seed funding, and facilities of incubation centers. In Pakistan, there are many good public sector research institutes, yet there is a void gap in the private sector. Only few research institute are meant for research and development. BJ Micro Lab is one of them. It is SECP registered company and is working in academia to promote and facilitate research in STEM. BJ Micro Lab is a women led initiative, and we are trying to promote research as a passion, not as an arduous burden. For this, we are continuously arranging training workshops and sessions. More than 100 students have been trained in ten different workshops arranged at BJ Micro Lab.Keywords: entrepreneurship, STEM, challenges, oppurtunties
Procedia PDF Downloads 1291083 Sustainable Housing in Steel: Prospects for Future World of Developing Countries
Authors: Poorva Kulkarni
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Developing countries are having significant additions to existing population of urban areas with loads of migrants from rural areas. There is a tremendous need to provide accommodation facility to cater to rapidly growing urban population. This leads to unprecedented growth in urban areas since the temporary shelters are constructed with any available material. Architecture in a broader sense serves to humanity in terms of making life of people happy and comfortable by providing comfortable shelters. It is also the need of the time for an architect to be extremely sensitive towards nature by providing design solution of human shelters with minimum impact on the environment. The sensitive approach towards designing of housing units and provision of comfortable and affordable housing units should go hand in hand for future growth of developing countries. Steel has proved itself a versatile material in terms of strength, uniformity and ease of operation and many such other advantages. Steel can be used as the most promising material for modern construction practices. The current research paper focuses on how effectively steel can be used probably in combination with other construction material to achieve the mentioned objectives for sustainable housing. The research available on sustainable housing in steel is studied along with few case studies of buildings with the efficient use of steel providing a solution with affordability and minimum harm to the environment. The research will conclude the effective solutions exploring possibilities of use of steel for sustainable housing units. The researcher shows how the use of steel in combination with other materials for human shelters can promote sustainable housing for community living which is the need of the time.Keywords: community living, steel, sustainable housing, urban area
Procedia PDF Downloads 2271082 Organic Matter Removal in Urban and Agroindustry Wastewater by Chemical Precipitation Process
Authors: Karina Santos Silvério, Fátima Carvalho, Maria Adelaide Almeida
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The impacts caused by anthropogenic actions on the water environment have been one of the main challenges of modern society. Population growth, added to water scarcity and climate change, points to a need to increase the resilience of production systems to increase efficiency regarding the management of wastewater generated in the different processes. Based on this context, the study developed under the NETA project (New Strategies in Wastewater Treatment) aimed to evaluate the efficiency of the Chemical Precipitation Process (CPP), using the hydrated lime (Ca(OH )₂) as a reagent in wastewater from the agroindustry sector, namely swine wastewater, slaughterhouse and urban wastewater, in order to make the productive means 100% circular, causing a direct positive impact on the environment. The purpose of CPP is to innovate in the field of effluent treatment technologies, as it allows rapid application and is economically profitable. In summary, the study was divided into four main stages: 1) Application of the reagent in a single step, raising the pH to 12.5 2) Obtaining sludge and treated effluent. 3) Natural neutralization of the effluent through Carbonation using atmospheric CO₂. 4) Characterization and evaluation of the feasibility of the chemical precipitation technique in the treatment of different wastewaters through the technique of determining the chemical oxygen demand (COD) and other supporting physical-chemical parameters. The results showed an approximate average removal efficiency above 80% for all effluents, highlighting the swine effluent with 90% removal, followed by urban effluent with 88% and slaughterhouse with 81% on average. Significant improvement was also obtained with regard to color and odor removal after Carbonation to pH 8.00.Keywords: agroindustry wastewater, urban wastewater, natural carbonatation, chemical precipitation technique
Procedia PDF Downloads 821081 Exploring the Role of Data Mining in Crime Classification: A Systematic Literature Review
Authors: Faisal Muhibuddin, Ani Dijah Rahajoe
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This in-depth exploration, through a systematic literature review, scrutinizes the nuanced role of data mining in the classification of criminal activities. The research focuses on investigating various methodological aspects and recent developments in leveraging data mining techniques to enhance the effectiveness and precision of crime categorization. Commencing with an exposition of the foundational concepts of crime classification and its evolutionary dynamics, this study details the paradigm shift from conventional methods towards approaches supported by data mining, addressing the challenges and complexities inherent in the modern crime landscape. Specifically, the research delves into various data mining techniques, including K-means clustering, Naïve Bayes, K-nearest neighbour, and clustering methods. A comprehensive review of the strengths and limitations of each technique provides insights into their respective contributions to improving crime classification models. The integration of diverse data sources takes centre stage in this research. A detailed analysis explores how the amalgamation of structured data (such as criminal records) and unstructured data (such as social media) can offer a holistic understanding of crime, enriching classification models with more profound insights. Furthermore, the study explores the temporal implications in crime classification, emphasizing the significance of considering temporal factors to comprehend long-term trends and seasonality. The availability of real-time data is also elucidated as a crucial element in enhancing responsiveness and accuracy in crime classification.Keywords: data mining, classification algorithm, naïve bayes, k-means clustering, k-nearest neigbhor, crime, data analysis, sistematic literature review
Procedia PDF Downloads 661080 Application of Electro-Optical Hybrid Cables in Horizontal Well Production Logging
Authors: Daofan Guo, Dong Yang
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For decades, well logging with coiled tubing has relied solely on surface data such as pump pressure, wellhead pressure, depth counter, and weight indicator readings. While this data serves the oil industry well, modern smart logging utilizes real-time downhole information, which automatically increases operational efficiency and optimizes intervention qualities. For example, downhole pressure, temperature, and depth measurement data can be transmitted through the electro-optical hybrid cable in the coiled tubing to surface operators on a real-time base. This paper mainly introduces the unique structural features and various applications of the electro-optical hybrid cables which were deployed into downhole with the help of coiled tubing technology. Fiber optic elements in the cable enable optical communications and distributed measurements, such as distributed temperature and acoustic sensing. The electrical elements provide continuous surface power for downhole tools, eliminating the limitations of traditional batteries, such as temperature, operating time, and safety concerns. The electrical elements also enable cable telemetry operation of cable tools. Both power supply and signal transmission were integrated into an electro-optical hybrid cable, and the downhole information can be captured by downhole electrical sensors and distributed optical sensing technologies, then travels up through an optical fiber to the surface, which greatly improves the accuracy of measurement data transmission.Keywords: electro-optical hybrid cable, underground photoelectric composite cable, seismic cable, coiled tubing, real-time monitoring
Procedia PDF Downloads 1421079 Investigating the performance of machine learning models on PM2.5 forecasts: A case study in the city of Thessaloniki
Authors: Alexandros Pournaras, Anastasia Papadopoulou, Serafim Kontos, Anastasios Karakostas
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The air quality of modern cities is an important concern, as poor air quality contributes to human health and environmental issues. Reliable air quality forecasting has, thus, gained scientific and governmental attention as an essential tool that enables authorities to take proactive measures for public safety. In this study, the potential of Machine Learning (ML) models to forecast PM2.5 at local scale is investigated in the city of Thessaloniki, the second largest city in Greece, which has been struggling with the persistent issue of air pollution. ML models, with proven ability to address timeseries forecasting, are employed to predict the PM2.5 concentrations and the respective Air Quality Index 5-days ahead by learning from daily historical air quality and meteorological data from 2014 to 2016 and gathered from two stations with different land use characteristics in the urban fabric of Thessaloniki. The performance of the ML models on PM2.5 concentrations is evaluated with common statistical methods, such as R squared (r²) and Root Mean Squared Error (RMSE), utilizing a portion of the stations’ measurements as test set. A multi-categorical evaluation is utilized for the assessment of their performance on respective AQIs. Several conclusions were made from the experiments conducted. Experimenting on MLs’ configuration revealed a moderate effect of various parameters and training schemas on the model’s predictions. Their performance of all these models were found to produce satisfactory results on PM2.5 concentrations. In addition, their application on untrained stations showed that these models can perform well, indicating a generalized behavior. Moreover, their performance on AQI was even better, showing that the MLs can be used as predictors for AQI, which is the direct information provided to the general public.Keywords: Air Quality, AQ Forecasting, AQI, Machine Learning, PM2.5
Procedia PDF Downloads 771078 Chemical Study of Volatile Organic Compounds (VOCS) from Xylopia aromatica (LAM.) Mart (Annonaceae)
Authors: Vanessa G. P. Severino, JOÃO Gabriel M. Junqueira, Michelle N. G. do Nascimento, Francisco W. B. Aquino, João B. Fernandes, Ana P. Terezan
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The scientific interest in analyzing VOCs represents a significant modern research field as a result of importance in most branches of the present life and industry. Therefore it is extremely important to investigate, identify and isolate volatile substances, since they can be used in different areas, such as food, medicine, cosmetics, perfumery, aromatherapy, pesticides, repellents and other household products through methods for extracting volatile constituents, such as solid phase microextraction (SPME), hydrodistillation (HD), solvent extraction (SE), Soxhlet extraction, supercritical fluid extraction (SFE), stream distillation (SD) and vacuum distillation (VD). The Chemometrics is an area of chemistry that uses statistical and mathematical tools for the planning and optimization of the experimental conditions, and to extract relevant chemical information multivariate chemical data. In this context, the focus of this work was the study of the chemical VOCs by SPME of the specie X. aromatica, in search of constituents that can be used in the industrial sector as well as in food, cosmetics and perfumery, since these areas industrial has a considerable role. In addition, by chemometric analysis, we sought to maximize the answers of this research, in order to search for the largest number of compounds. The investigation of flowers from X. aromatica in vitro and in alive mode proved consistent, but certain factors supposed influence the composition of metabolites, and the chemometric analysis strengthened the analysis. Thus, the study of the chemical composition of X. aromatica contributed to the VOCs knowledge of the species and a possible application.Keywords: chemometrics, flowers, HS-SPME, Xylopia aromatica
Procedia PDF Downloads 3621077 In-Flight Radiometric Performances Analysis of an Airborne Optical Payload
Authors: Caixia Gao, Chuanrong Li, Lingli Tang, Lingling Ma, Yaokai Liu, Xinhong Wang, Yongsheng Zhou
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Performances analysis of remote sensing sensor is required to pursue a range of scientific research and application objectives. Laboratory analysis of any remote sensing instrument is essential, but not sufficient to establish a valid inflight one. In this study, with the aid of the in situ measurements and corresponding image of three-gray scale permanent artificial target, the in-flight radiometric performances analyses (in-flight radiometric calibration, dynamic range and response linearity, signal-noise-ratio (SNR), radiometric resolution) of self-developed short-wave infrared (SWIR) camera are performed. To acquire the inflight calibration coefficients of the SWIR camera, the at-sensor radiances (Li) for the artificial targets are firstly simulated with in situ measurements (atmosphere parameter and spectral reflectance of the target) and viewing geometries using MODTRAN model. With these radiances and the corresponding digital numbers (DN) in the image, a straight line with a formulation of L = G × DN + B is fitted by a minimization regression method, and the fitted coefficients, G and B, are inflight calibration coefficients. And then the high point (LH) and the low point (LL) of dynamic range can be described as LH= (G × DNH + B) and LL= B, respectively, where DNH is equal to 2n − 1 (n is the quantization number of the payload). Meanwhile, the sensor’s response linearity (δ) is described as the correlation coefficient of the regressed line. The results show that the calibration coefficients (G and B) are 0.0083 W·sr−1m−2µm−1 and −3.5 W·sr−1m−2µm−1; the low point of dynamic range is −3.5 W·sr−1m−2µm−1 and the high point is 30.5 W·sr−1m−2µm−1; the response linearity is approximately 99%. Furthermore, a SNR normalization method is used to assess the sensor’s SNR, and the normalized SNR is about 59.6 when the mean value of radiance is equal to 11.0 W·sr−1m−2µm−1; subsequently, the radiometric resolution is calculated about 0.1845 W•sr-1m-2μm-1. Moreover, in order to validate the result, a comparison of the measured radiance with a radiative-transfer-code-predicted over four portable artificial targets with reflectance of 20%, 30%, 40%, 50% respectively, is performed. It is noted that relative error for the calibration is within 6.6%.Keywords: calibration and validation site, SWIR camera, in-flight radiometric calibration, dynamic range, response linearity
Procedia PDF Downloads 2711076 Nonlinear Estimation Model for Rail Track Deterioration
Authors: M. Karimpour, L. Hitihamillage, N. Elkhoury, S. Moridpour, R. Hesami
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Rail transport authorities around the world have been facing a significant challenge when predicting rail infrastructure maintenance work for a long period of time. Generally, maintenance monitoring and prediction is conducted manually. With the restrictions in economy, the rail transport authorities are in pursuit of improved modern methods, which can provide precise prediction of rail maintenance time and location. The expectation from such a method is to develop models to minimize the human error that is strongly related to manual prediction. Such models will help them in understanding how the track degradation occurs overtime under the change in different conditions (e.g. rail load, rail type, rail profile). They need a well-structured technique to identify the precise time that rail tracks fail in order to minimize the maintenance cost/time and secure the vehicles. The rail track characteristics that have been collected over the years will be used in developing rail track degradation prediction models. Since these data have been collected in large volumes and the data collection is done both electronically and manually, it is possible to have some errors. Sometimes these errors make it impossible to use them in prediction model development. This is one of the major drawbacks in rail track degradation prediction. An accurate model can play a key role in the estimation of the long-term behavior of rail tracks. Accurate models increase the track safety and decrease the cost of maintenance in long term. In this research, a short review of rail track degradation prediction models has been discussed before estimating rail track degradation for the curve sections of Melbourne tram track system using Adaptive Network-based Fuzzy Inference System (ANFIS) model.Keywords: ANFIS, MGT, prediction modeling, rail track degradation
Procedia PDF Downloads 3361075 The Influence of Architectural-Planning Structure of Cities on Their Sustainable Development
Authors: M. Kashiripoor
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Existing indicators for sustainable urban development do not identify the features of cities’ planning structures and their architecture. Iranian city has special relevance problem of assessing the conformity of their planning and development of the concept of sustainable development. Based on theoretical sources, the author concludes that, despite the existence of common indicators for sustainable development of settlements, specialized evaluation criteria city structure planning has not been developed. He is trying to fill this gap and put forward a system of indicators characterizing the level of development of the architectural-planning structure of the city. The proposed system of indicators is designed based on technical and economic urban standard indicators from different countries. Alternative designing systems and requirements of modern rating systems like LEED-ND comprise a criterion for evaluation of urban structures in accordance with principles of "Green" building and New Urbanism. Urban development trends are close in spirit of sustainable development and developed under its influence. The study allowed concluding that a system of indicators to identify the relevant architectural-planning structure of the city, requirements of sustainable development, should be adapted to the conditions of each country, particularly in Iran. The article attempts typology proposed indicators, which are presented in tabular form and are divided into two types: planning and spatial. This article discusses the known indicators of sustainable development and proposed specific system of indicators characterizing the level of development of architectural-planning structure of the city. This article examines indicators for evaluating level of city' planning structure development. The proposed system of indicators is derived from the urban planning standards and rating systems such as LEED-ND, BREEAM Community and CASBEE-UD.Keywords: architectural-planning structure of cities, urban planning indicators, urban space indicators, urban development
Procedia PDF Downloads 6361074 A Corporate Social Responsibility Project to Improve the Democratization of Scientific Education in Brazil
Authors: Denise Levy
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Nuclear technology is part of our everyday life and its beneficial applications help to improve the quality of our lives. Nevertheless, in Brazil, most often the media and social networks tend to associate radiation to nuclear weapons and major accidents, and there is still great misunderstanding about the peaceful applications of nuclear science. The Educational Portal Radioatividades (Radioactivities) is a corporate social responsibility initiative that takes advantage of the growing impact of Internet to offer high quality scientific information for teachers and students throughout Brazil. This web-based initiative focusses on the positive applications of nuclear technology, presenting the several contributions of ionizing radiation in different contexts, such as nuclear medicine, agriculture techniques, food safety and electric power generation, proving nuclear technology as part of modern life and a must to improve the quality of our lifestyle. This educational project aims to contribute for democratization of scientific education and social inclusion, approaching society to scientific knowledge, promoting critical thinking and inspiring further reflections. The website offers a wide variety of ludic activities such as curiosities, interactive exercises and short courses. Moreover, teachers are offered free web-based material with full instructions to be developed in class. Since year 2013, the project has been developed and improved according to a comprehensive study about the realistic scenario of ICTs infrastructure in Brazilian schools and in full compliance with the best e-learning national and international recommendations.Keywords: information and communication technologies, nuclear technology, science communication, society and education
Procedia PDF Downloads 3261073 Perspective for the Creation of Molecular Imprinted Polymers from Coal Waste
Authors: Alma Khasenovna Zhakina, Arnt Oxana Vasilievna, Vasilets Evgeny Petrovich
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The aim of this project is to develop methods for obtaining new molecularly imprinted polymers from coal waste to study their structure, structural and morphological features and properties. Recently, the development of molecularly imprinted polymers has become one of the hot topics for researchers. Modern research indicates the broad prospects of rapidly developing molecular imprinting technologies for creating a new generation of sorption materials. The attractiveness of this area of research lies in the fact that the use of imprinted polymers is not limited to scientific research; they are already being introduced in the chemical, pharmaceutical and biotechnological industries, primarily at the stages of purification of the final product. For the use of molecularly imprinted polymers in the development of sorption material, their ability to selectively remove pollutants, including trace concentrations, is of fundamental importance, and the exceptional stability of polymeric materials under harsh conditions makes it possible to simplify the process of water purification as a whole. The scientific and technical effect is associated with the development of technologies for the production of new molecularly imprinted polymers, the establishment of optimal conditions for their production and the creation of effective imprinted sorbents on their basis for wastewater treatment from heavy metals. The social effect is due to the fact that the use of coal waste as a feedstock for the production of imprinted sorbents will make it possible in the future to create new industries with additional jobs and obtain competitive multi-purpose products. The economic and multiplier effect is associated with the low cost of the final product due to the involvement of local coal waste in the production, reduction of transport, customs and other costs.Keywords: imprinted polymers, coal waste, polymerization, template, customized sorbents
Procedia PDF Downloads 661072 Chance One’s Arm: Critical Evaluation on Laws of Sports Gambling in India
Authors: Archen Sara Vincent
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Gambling is the practice or act of betting or wagering on uncertain events with the hope of winning money or any other valuable assets. Nowadays, the practice of gambling can be seen in almost all grounds of events, especially in sports. In sports, this is commonly known among people as sports betting. The history of gambling can be traced about 2,000 years back. It originated from Greeks, from Greeks to the Romans, then to England, where betting on horse races was much popular among the elites. The evolution of gambling in sports has made a greater impact in the modern era. In India, the legality of gambling in sports is regulated by The Public Gambling Act 1867, which prohibits gambling activities in public places. The major draw of this statute is that it does not have specific laws regarding online sports gambling. Section 30 of The Indian Contract Act 1872 considers wagering agreements void. However, there are certain exceptions for this section, that is, (1) state-owned lotteries and (2) wagering on horse races with a sum of Rupees 500 or upward. As per the Indian Constitution, the rules regarding sports gambling are within the powers of the state legislatures. Some of the states have enacted their own laws which explicitly permit or prohibit gambling within their jurisdiction. Recently in Tamilnadu, The Tamilnadu Gaming Act was amended in 2021 to completely ban online gambling and betting. Moreover, the Central Government has introduced the Online Gaming and Prevention of Fraud Bill, 2018, to legalize and regulate sports betting in India. However, this bill has not yet been passed as law. Now as the Indian legal system does not have a specific rule regarding online sports gambling, sports betting companies use this major drawback and attract people to use the gambling and betting apps by advertising with well-known sports players and other celebrities. This paper aims to critically evaluate gambling in sports and the laws relating to it in India.Keywords: history of gambling, The Public Gambling Act 1862, state legislations, gambling in India
Procedia PDF Downloads 791071 Medical Ethics in the Hospital: Towards Quality Ethics Consultation
Authors: Dina Siniora, Jasia Baig
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During the past few decades, the healthcare system has undergone profound changes in their healthcare decision-making competencies and moral aptitudes due to the vast advancement in technology, clinical skills, and scientific knowledge. Healthcare decision-making deals with morally contentious dilemmas ranging from illness, life and death judgments that require sensitivity and awareness towards the patient’s preferences while taking into consideration medicine’s abilities and boundaries. As the ever-evolving field of medicine continues to become more scientifically and morally multifarious; physicians and the hospital administrators increasingly rely on ethics committees to resolve problems that arise in everyday patient care. The role and latitude of responsibilities of ethics committees which includes being dispute intermediaries, moral analysts, policy educators, counselors, advocates, and reviewers; suggest the importance and effectiveness of a fully integrated committee. Despite achievements on Integrated Ethics and progress in standards and competencies, there is an imminent necessity for further improvement in quality within ethics consultation services in areas of credentialing, professionalism and standards of quality, as well as the quality of healthcare throughout the system. These concerns can be resolved first by collecting data about particular quality gaps and comprehend the level to which ethics committees are consistent with newly published ASBH quality standards. Policymakers should pursue improvement strategies that target both academic bioethics community and major stakeholders at hospitals, who directly influence ethics committees. This broader approach oriented towards education and intervention outcome in conjunction with preventive ethics to address disparities in quality on a systematic level. Adopting tools for improving competencies and processes within ethics consultation by implementing a credentialing process, upholding normative significance for the ASBH core competencies, advocating for professional Code of Ethics, and further clarifying the internal structures will improve productivity, patient satisfaction, and institutional integrity. This cannot be systemically achieved without a written certification exam for HCEC practitioners, credentialing and privileging HCEC practitioners at the hospital level, and accrediting HCEC services at the institutional level.Keywords: ethics consultation, hospital, medical ethics, quality
Procedia PDF Downloads 1891070 Investigating Effects of Vehicle Speed and Road PSDs on Response of a 35-Ton Heavy Commercial Vehicle (HCV) Using Mathematical Modelling
Authors: Amal G. Kurian
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The use of mathematical modeling has seen a considerable boost in recent times with the development of many advanced algorithms and mathematical modeling capabilities. The advantages this method has over other methods are that they are much closer to standard physics theories and thus represent a better theoretical model. They take lesser solving time and have the ability to change various parameters for optimization, which is a big advantage, especially in automotive industry. This thesis work focuses on a thorough investigation of the effects of vehicle speed and road roughness on a heavy commercial vehicle ride and structural dynamic responses. Since commercial vehicles are kept in operation continuously for longer periods of time, it is important to study effects of various physical conditions on the vehicle and its user. For this purpose, various experimental as well as simulation methodologies, are adopted ranging from experimental transfer path analysis to various road scenario simulations. To effectively investigate and eliminate several causes of unwanted responses, an efficient and robust technique is needed. Carrying forward this motivation, the present work focuses on the development of a mathematical model of a 4-axle configuration heavy commercial vehicle (HCV) capable of calculating responses of the vehicle on different road PSD inputs and vehicle speeds. Outputs from the model will include response transfer functions and PSDs and wheel forces experienced. A MATLAB code will be developed to implement the objectives in a robust and flexible manner which can be exploited further in a study of responses due to various suspension parameters, loading conditions as well as vehicle dimensions. The thesis work resulted in quantifying the effect of various physical conditions on ride comfort of the vehicle. An increase in discomfort is seen with velocity increase; also the effect of road profiles has a considerable effect on comfort of the driver. Details of dominant modes at each frequency are analysed and mentioned in work. The reduction in ride height or deflection of tire and suspension with loading along with load on each axle is analysed and it is seen that the front axle supports a greater portion of vehicle weight while more of payload weight comes on fourth and third axles. The deflection of the vehicle is seen to be well inside acceptable limits.Keywords: mathematical modeling, HCV, suspension, ride analysis
Procedia PDF Downloads 2591069 Determining the Collaboration and Challenges of Public Employment Service with Stakeholders, Employers and Job Seekers: In Case of Amhara National Regional State, Ethiopia
Authors: Redie Bezabih Hailu
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Unemployment is a problem of nations that needs a continuous research. This study aimed to determine the collaborations and challenges of public employment service (PES) with special emphasis of stakeholders, employers and job seekers. The researcher used pragmatic philosophy, exploratory design and inductive approach to collect data from the respondents using interview and focused group discussion techniques. PES provides job market information, vocational counseling, and training. As PES is not fully furnished with man power, budget, modern technologies, it is providing less adequate services to the employers and job seekers. Matching job seekers with job vacancies is the major challenge for the center and using paper-based data management system too. There is also a number of job seekers in spite of very limited number of vacancies that the service provision is poor due to the fact that there is low level of vacancies and high level of job seekers. The center has collaboration with AFE, AYA, BoTVED, BoWCY, and CETU. The major challenges with this collaborations was the absence of operational guidelines to evaluate effectiveness and performance, lottery method of selecting candidates for vacancies and nepotism or favoritism were challenges for job seekers. On the other hand, (COVID-19) pandemic, inability to get skilled labor, absence of standardized payment, expectation of job seekers and less educational quality and mass graduation were another challenges for employment services. The study recommended quality education and training, operational guideline for collaboration, technology based labor market information system and suggested further studies on quality of PES.Keywords: public employment service, collaborations, stakeholders, employers, job seekers
Procedia PDF Downloads 501068 Using Game Engines in Lightning Shielding: The Application of the Rolling Spheres Method on Virtual As-Built Power Substations
Authors: Yuri A. Gruber, Matheus Rosendo, Ulisses G. A. Casemiro, Klaus de Geus, Rafael T. Bee
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Lightning strikes can cause severe negative impacts to the electrical sector causing direct damage to equipment as well as shutdowns, especially when occurring in power substations. In order to mitigate this problem, a meticulous planning of the power substation protection system is of vital importance. A critical part of this is the distribution of shielding wires through the substation, which creates a 3D imaginary protection mesh similar to a circus tarpaulin. Equipment enclosed in the volume defined by that 3D mesh is considered protected against lightning strikes. The use of traditional methods of longitudinal cutting analysis based on 2D CAD tools makes the process laborious and the results obtained may not guarantee satisfactory protection of electrical equipment. This work describes the application of a Game Engine to the problem of lightning protection of power substations providing the visualization of the 3D protection mesh, the amount of protected components and the highlight of equipment which remain unprotected. In addition, aspects regarding the implementation and the advantages of approaching the problem using Unreal® Engine 4 are described. In order to validate results, a comparison with traditional 2D methods is applied to the same case study to which the proposed technique has been applied. Finally, a comparative study involving different levels of protection using the technique developed in this work is presented, showing that modern game engines can be a powerful accessory for simulations in several areas of engineering.Keywords: game engine, rolling spheres method, substation protection, UE4, Unreal Engine 4
Procedia PDF Downloads 5271067 A Reflection: Looking the Pattern of Political Party (Gerindra Party) Campaign by Social Media in Indonesia General Election 2014
Authors: Clara Stella Anugerah
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This study actually is a reflection of the general election in 2014. The researcher was interested in this case as the assessment of several phenomenons that happened recently. One of them is the use of social media for the campaign. By this modern era, social media becomes closer with society. It gains the communication process, and by the time being communicating others also becomes easier than before. Furthermore, social media can minimize the cost of communication with many people as a far distance that often comes to be an obstacle of communication does not become a big problem anymore. In Indonesia, the advantages of social media were used by a political party, Gerindra, to face the election that was held on 2014. Actually Gerindra is a newly formed political party that was established in 2008. In spite of Gerindra is the new comer in the election, according to the General Election Committee’s data in Indonesia, Gerindra has the biggest budget than others to cost campaign in social media. Because of that, this research wants to look “how is the pattern of Gerindra party’s campaign to face the general election in 2014? To ask that question, the theory used for this research is campaign method based on ICT (Information Communication Technology) by Rummele. According to the rummele, Gerindra was a party that used a product of social media massively, mainly facebook and twitter. According to that observation, this research focus on campaign that had been done by Gerindra in both of those social media by the time window given by KPU (General Election Committee) on Maret 16th until April 5th, 2014. The conclusion was derived by content analysis method that was used in the methodology. In this context, that method was used while interpreting the content uploaded by Gerindra to facebook or twitter, such as picture and writing. Finally, by that method and reflecting the rummele theory, this research inferred that the patern used for Gerindra’s campaign in social media tends to be top-down. It means: Gerindra showed uncommunicative tendency in social media and only want to catch much mass without mentioned a mission and vision clearly.Keywords: Gerindra party, political party, social media, campaign, general election on 2014
Procedia PDF Downloads 4851066 The Effect of Transparent Oil Wood Stain on the Colour Stability of Spruce Wood during Weathering
Authors: Eliska Oberhofnerova, Milos Panek, Stepan Hysek, Martin Lexa
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Nowadays the use of wood, both indoors and outdoors, is constantly increasing. However wood is a natural organic material and in the exterior is subjected to a degradation process caused by abiotic factors (solar radiation, rain, moisture, wind, dust etc.). This process affects only surface layers of wood but neglecting some of the basic rules of wood protection leads to increased possibility of biological agents attack and thereby influences a function of the wood element. The process of wood degradation can be decreased by proper surface treatment, especially in the case of less naturally durable wood species, as spruce. Modern coating systems are subjected to many requirements such as colour stability, hydrophobicity, low volatile organic compound (VOC) content, long service life or easy maintenance. The aim of this study is to evaluate the colour stability of spruce wood (Picea abies), as the basic parameter indicating the coating durability, treated with two layers of transparent natural oil wood stain and exposed to outdoor conditions. The test specimens were exposed for 2 years to natural weathering and 2000 hours to artificial weathering in UV-chamber. The colour parameters were measured before and during exposure to weathering by the spectrophotometer according to CIELab colour space. The comparison between untreated and treated wood and both testing procedures was carried out. The results showed a significant effect of coating on the colour stability of wood, as expected. Nevertheless, increasing colour changes of wood observed during the exposure to weathering differed according to applied testing procedure - natural and artificial.Keywords: colour stability, natural and artificial weathering, spruce wood, transparent coating
Procedia PDF Downloads 2201065 Peculiarities of Internal Friction and Shear Modulus in 60Co γ-Rays Irradiated Monocrystalline SiGe Alloys
Authors: I. Kurashvili, G. Darsavelidze, T. Kimeridze, G. Chubinidze, I. Tabatadze
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At present, a number of modern semiconductor devices based on SiGe alloys have been created in which the latest achievements of high technologies are used. These devices might cause significant changes to networking, computing, and space technology. In the nearest future new materials based on SiGe will be able to restrict the A3B5 and Si technologies and firmly establish themselves in medium frequency electronics. Effective realization of these prospects requires the solution of prediction and controlling of structural state and dynamical physical –mechanical properties of new SiGe materials. Based on these circumstances, a complex investigation of structural defects and structural-sensitive dynamic mechanical characteristics of SiGe alloys under different external impacts (deformation, radiation, thermal cycling) acquires great importance. Internal friction (IF) and shear modulus temperature and amplitude dependences of the monocrystalline boron-doped Si1-xGex(x≤0.05) alloys grown by Czochralski technique is studied in initial and 60Co gamma-irradiated states. In the initial samples, a set of dislocation origin relaxation processes and accompanying modulus defects are revealed in a temperature interval of 400-800 ⁰C. It is shown that after gamma-irradiation intensity of relaxation internal friction in the vicinity of 280 ⁰C increases and simultaneously activation parameters of high temperature relaxation processes reveal clear rising. It is proposed that these changes of dynamical mechanical characteristics might be caused by a decrease of the dislocation mobility in the Cottrell atmosphere enriched by the radiation defects.Keywords: internal friction, shear modulus, gamma-irradiation, SiGe alloys
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