Search results for: semi-discretization method
13366 Competency Model as a Key Tool for Managing People in Organizations: Presentation of a Model
Authors: Andrea ČopíKová
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Competency Based Management is a new approach to management, which solves organization’s challenges with complexity and with the aim to find and solve organization’s problems and learn how to avoid these in future. They teach the organizations to create, apart from the state of stability – that is temporary, vital organization, which is permanently able to utilize and profit from internal and external opportunities. The aim of this paper is to propose a process of competency model design, based on which a competency model for a financial department manager in a production company will be created. Competency models are very useful tool in many personnel processes in any organization. They are used for acquiring and selection of employees, designing training and development activities, employees’ evaluation, and they can be used as a guide for a career planning and as a tool for succession planning especially for managerial positions. When creating a competency model the method AHP (Analytic Hierarchy Process) and quantitative pair-wise comparison (Saaty’s method) will be used; these methods belong among the most used methods for the determination of weights, and it is used in the AHP procedure. The introduction part of the paper consists of the research results pertaining to the use of competency model in practice and then the issue of competency and competency models is explained. The application part describes in detail proposed methodology for the creation of competency models, based on which the competency model for the position of financial department manager in a foreign manufacturing company, will be created. In the conclusion of the paper, the final competency model will be shown for above mentioned position. The competency model divides selected competencies into three groups that are managerial, interpersonal and functional. The model describes in detail individual levels of competencies, their target value (required level) and the level of importance.Keywords: analytic hierarchy process, competency, competency model, quantitative pairwise comparison
Procedia PDF Downloads 23613365 Seismic Reinforcement of Existing Japanese Wooden Houses Using Folded Exterior Thin Steel Plates
Authors: Jiro Takagi
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Approximately 90 percent of the casualties in the near-fault-type Kobe earthquake in 1995 resulted from the collapse of wooden houses, although a limited number of collapses of this type of building were reported in the more recent off-shore-type Tohoku Earthquake in 2011 (excluding direct damage by the Tsunami). Kumamoto earthquake in 2016 also revealed the vulnerability of old wooden houses in Japan. There are approximately 24.5 million wooden houses in Japan and roughly 40 percent of them are considered to have the inadequate seismic-resisting capacity. Therefore, seismic strengthening of these wooden houses is an urgent task. However, it has not been quickly done for various reasons, including cost and inconvenience during the reinforcing work. Residents typically spend their money on improvements that more directly affect their daily housing environment (such as interior renovation, equipment renewal, and placement of thermal insulation) rather than on strengthening against extremely rare events such as large earthquakes. Considering this tendency of residents, a new approach to developing a seismic strengthening method for wooden houses is needed. The seismic reinforcement method developed in this research uses folded galvanized thin steel plates as both shear walls and the new exterior architectural finish. The existing finish is not removed. Because galvanized steel plates are aesthetic and durable, they are commonly used in modern Japanese buildings on roofs and walls. Residents could feel a physical change through the reinforcement, covering existing exterior walls with steel plates. Also, this exterior reinforcement can be installed with only outdoor work, thereby reducing inconvenience for residents since they would not be required to move out temporarily during construction. The Durability of the exterior is enhanced, and the reinforcing work can be done efficiently since perfect water protection is not required for the new finish. In this method, the entire exterior surface would function as shear walls and thus the pull-out force induced by seismic lateral load would be significantly reduced as compared with a typical reinforcement scheme of adding braces in selected frames. Consequently, reinforcing details of anchors to the foundations would be less difficult. In order to attach the exterior galvanized thin steel plates to the houses, new wooden beams are placed next to the existing beams. In this research, steel connections between the existing and new beams are developed, which contain a gap for the existing finish between the two beams. The thin steel plates are screwed to the new beams and the connecting vertical members. The seismic-resisting performance of the shear walls with thin steel plates is experimentally verified both for the frames and connections. It is confirmed that the performance is high enough for bracing general wooden houses.Keywords: experiment, seismic reinforcement, thin steel plates, wooden houses
Procedia PDF Downloads 22213364 Furniture Embodied Carbon Calculator for Interior Design Projects
Authors: Javkhlan Nyamjav, Simona Fischer, Lauren Garner, Veronica McCracken
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Current whole building life cycle assessments (LCA) primarily focus on structural and major architectural elements to measure building embodied carbon. Most of the interior finishes and fixtures are available on digital tools (such as Tally); however, furniture is still left unaccounted for. Due to its repeated refreshments and its complexity, furniture embodied carbon can accumulate over time, becoming comparable to structure and envelope numbers. This paper presents a method to calculate the Global Warming Potential (GWP) of furniture elements in commercial buildings. The calculator uses the quantity takeoff method with GWP averages gathered from environmental product declarations (EPD). The data was collected from EPD databases and furniture manufacturers from North America to Europe. A total of 48 GWP numbers were collected, with 16 GWP coming from alternative EPD. The finalized calculator shows the average GWP of typical commercial furniture and helps the decision-making process to reduce embodied carbon. The calculator was tested on MSR Design projects and showed furniture can account for more than half of the interior embodied carbon. The calculator highlights the importance of adding furniture to the overall conversation. However, the data collection process showed a) acquiring furniture EPD is not straightforward as other building materials; b) there are very limited furniture EPD, which can be explained from many perspectives, including the EPD price; c) the EPD themselves vary in terms of units, LCA scopes, and timeframes, which makes it hard to compare the products. Even though there are current limitations, the emerging focus on interior embodied carbon will create more demand for furniture EPD. It will allow manufacturers to represent all their efforts on reducing embodied carbon. In addition, the study concludes with recommendations on how designers can reduce furniture-embodied carbon through reuse and closed-loop systems.Keywords: furniture, embodied carbon, calculator, tenant improvement, interior design
Procedia PDF Downloads 20613363 Preparation Static Dissipative Nanocomposites of Alkaline Earth Metal Doped Aluminium Oxide and Methyl Vinyl Silicone Polymer
Authors: Aparna M. Joshi
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Methyl vinyl silicone polymer (VMQ) - alkaline earth metal doped aluminium oxide composites are prepared by conventional two rolls open mill mixing method. Doped aluminium oxides (DAO) using silvery white coloured alkaline earth metals such as Mg and Ca as dopants in the concentration of 0.4 % are synthesized by microwave combustion method and referred as MA ( Mg doped aluminium oxide) and CA ( Ca doped aluminium oxide). The as-synthesized materials are characterized for the electrical resistance, X–ray diffraction, FE-SEM, TEM and FTIR. The electrical resistances of the DAOs are observed to be ~ 8-20 MΩ. This means that the resistance of aluminium oxide (Corundum) α-Al2O3 which is ~ 1010Ω is reduced by the order of ~ 103 to 104 Ω after doping. XRD studies reveal the doping of Mg and Ca in aluminium oxide. The microstructural study using FE-SEM shows the flaky clusterous structures with the thickness of the flakes between 10 and 20 nm. TEM images depict the rod-shaped morphological geometry of the particles with the diameter of ~50-70 nm. The nanocomposites are synthesized by incorporating the DAOs in the concentration of 75 phr (parts per hundred parts of rubber) into VMQ polymer. The electrical resistance of VMQ polymer, which is ~ 1015Ω, drops by the order of 108Ω. There is a retention of the electrical resistance of ~ 30-50 MΩ for the nanocomposites which is a static dissipative range of electricity. In this work white coloured electrically conductive VMQ polymer-DAO nanocomposites (MAVMQ for Mg doping and CAVMQ for Ca doping) have been synthesized. The physical and mechanical properties of the composites such as specific gravity, hardness, tensile strength and rebound resilience are measured. Hardness and tensile strength are found to increase, with the negligible alteration in the other properties.Keywords: doped aluminium oxide, methyl vinyl silicone polymer, microwave synthesis, static dissipation
Procedia PDF Downloads 54913362 Analytical Method for Seismic Analysis of Shaft-Tunnel Junction under Longitudinal Excitations
Authors: Jinghua Zhang
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Shaft-tunnel junction is a typical case of the structural nonuniformity in underground structures. The shaft and the tunnel possess greatly different structural features. Even under uniform excitations, they tend to behave discrepantly. Studies on shaft-tunnel junctions are mainly performed numerically. Shaking table tests are also conducted. Although many numerical and experimental data are obtained, an analytical solution still has great merits of gaining more insights into the shaft-tunnel problem. This paper will try to remedy the situation. Since the seismic responses of shaft-tunnel junctions are very related to directions of the excitations, they are studied in two scenarios: the longitudinal-excitation scenario and the transverse-excitation scenario. The former scenario will be addressed in this paper. Given that responses of the tunnel are highly dependent on the shaft, the analytical solutions would be developed firstly for the vertical shaft. Then, the seismic responses of the tunnel would be discussed. Since vertical shafts bear a resemblance to rigid caissons, the solution proposed in this paper is derived by introducing terms of shaft-tunnel and soil-tunnel interactions into equations originally developed for rigid caissons. The validity of the solution is examined by a validation model computed by finite element method. The mutual influence between the shaft and the tunnel is introduced. The soil-structure interactions are discussed parametrically based on the proposed equations. The shaft-tunnel relative displacement and the soil-tunnel relative stiffness are found to be the most important parameters affecting the magnitudes and distributions of the internal forces of the tunnel. A hinge-joint at the shaft-tunnel junction could significantly reduce the degree of stress concentration compared with a rigid joint.Keywords: analytical solution, longitudinal excitation, numerical validation , shaft-tunnel junction
Procedia PDF Downloads 15313361 Improving Electrical Safety through Enhanced Work Permits
Authors: Nuwan Karunarathna, Hemali Seneviratne
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Distribution Utilities inherently present electrical hazards for their workers in addition to the general public especially due to bare overhead lines spreading out over a large geographical area. Therefore, certain procedures such as; de-energization, verification of de-energization, isolation, lock-out tag-out and earthing are carried out to ensure safe working conditions when conducting maintenance work on de-energized overhead lines. However, measures must be taken to coordinate the above procedures and to ensure successful and accurate execution of those procedures. Issuing of 'Work Permits' is such a measure that is used by the Distribution Utility considered in this paper. Unfortunately, the Work Permit method adopted by the Distribution Utility concerned here has not been successful in creating the safe working conditions as expected which was evidenced by four (4) number of fatalities of workers due to electrocution occurred in the Distribution Utility from 2016 to 2018. Therefore, this paper attempts to identify deficiencies in the Work Permit method and related contributing factors through careful analysis of the four (4) fatalities and work place practices to rectify the short comings to prevent future incidents. The analysis shows that the present level of coordination between the 'Authorized Person' who issues the work permit and the 'Competent Person' who performs the actual work is grossly inadequate to achieve the intended safe working conditions. The paper identifies the need of active participation of a 'Control Person' who oversees the whole operation from a bird’s eye perspective and recommends further measures that are derived through the analysis of the fatalities to address the identified lapses in the current work permit system.Keywords: authorized person, competent person, control person, de-energization, distribution utility, isolation, lock-out tag-out, overhead lines, work permit
Procedia PDF Downloads 12513360 Blueprinting of a Normalized Supply Chain Processes: Results in Implementing Normalized Software Systems
Authors: Bassam Istanbouli
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With the technology evolving every day and with the increase in global competition, industries are always under the pressure to be the best. They need to provide good quality products at competitive prices, when and how the customer wants them. In order to achieve this level of service, products and their respective supply chain processes need to be flexible and evolvable; otherwise changes will be extremely expensive, slow and with many combinatorial effects. Those combinatorial effects impact the whole organizational structure, from a management, financial, documentation, logistics and specially the information system Enterprise Requirement Planning (ERP) perspective. By applying the normalized system concept/theory to segments of the supply chain, we believe minimal effects, especially at the time of launching an organization global software project. The purpose of this paper is to point out that if an organization wants to develop a software from scratch or implement an existing ERP software for their business needs and if their business processes are normalized and modular then most probably this will yield to a normalized and modular software system that can be easily modified when the business evolves. Another important goal of this paper is to increase the awareness regarding the design of the business processes in a software implementation project. If the blueprints created are normalized then the software developers and configurators will use those modular blueprints to map them into modular software. This paper only prepares the ground for further studies; the above concept will be supported by going through the steps of developing, configuring and/or implementing a software system for an organization by using two methods: The Software Development Lifecycle method (SDLC) and the Accelerated SAP implementation method (ASAP). Both methods start with the customer requirements, then blue printing of its business processes and finally mapping those processes into a software system. Since those requirements and processes are the starting point of the implementation process, then normalizing those processes will end up in a normalizing software.Keywords: blueprint, ERP, modular, normalized
Procedia PDF Downloads 13113359 Diffuse CO₂ Degassing to Study Blind Geothermal Systems: The Acoculco, Puebla (Mexico) Case Study
Authors: Mirna Guevara, Edgar Santoyo, Daniel Perez-Zarate, Erika Almirudis
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The Acoculco caldera located in Puebla (Mexico) has been preliminary identified as a blind hot-dry rock geothermal system. Two drilled wells suggest the existence of high temperatures >300°C and non-conventional tools are been applied to study this system. A comprehensive survey of soil-gas (CO₂) flux measurements (1,500 sites) was carried out during the dry seasons over almost two years (2015 and 2016). Isotopic analyses of δ¹³CCO₂ were performed to discriminate the origin source of the CO2 fluxes. The soil CO2 flux measurements were made in situ by the accumulation chamber method, whereas gas samples for δ13CCO2 were selectively collected from the accumulation chamber with evacuated gas vials via a septum. Two anomalous geothermal zones were identified as a result of these campaigns: Los Azufres (19°55'29.4'' N; 98°08'39.9'' W; 2,839 masl) and Alcaparrosa (19°55'20.6'' N; 98°08'38.3'' W; 2,845 masl). To elucidate the origin of the C in soil CO₂ fluxes, the isotopic signature of δ¹³C was used. Graphical Statistical Analysis (GSA) and a three end-member mixing diagram were used to corroborate the presence of distinctive statistical samples, and trends for the diffuse gas fluxes. Spatial and temporal distributions of the CO₂ fluxes were studied. High CO₂ emission rates up to 38,217 g/m2/d and 33,706 g/m2/d were measured for the Los Azufres and Alcaparrosa respectively; whereas the δ¹³C signatures showed values ranging from -3.4 to -5.5 o/oo for both zones, confirming their magmatic origin. This study has provided a valuable framework to set the direction of further exploration campaigns in the Acoculco caldera. Acknowledgements: The authors acknowledge the funding received from CeMIE-Geo P09 project (SENER-CONACyT).Keywords: accumulation chamber method, carbon dioxide, diffusive degassing, geothermal exploration
Procedia PDF Downloads 25713358 An Exploratory Study on 'Sub-Region Life Circle' in Chinese Big Cities Based on Human High-Probability Daily Activity: Characteristic and Formation Mechanism as a Case of Wuhan
Authors: Zhuoran Shan, Li Wan, Xianchun Zhang
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With an increasing trend of regionalization and polycentricity in Chinese contemporary big cities, “sub-region life circle” turns to be an effective method on rational organization of urban function and spatial structure. By the method of questionnaire, network big data, route inversion on internet map, GIS spatial analysis and logistic regression, this article makes research on characteristic and formation mechanism of “sub-region life circle” based on human high-probability daily activity in Chinese big cities. Firstly, it shows that “sub-region life circle” has been a new general spatial sphere of residents' high-probability daily activity and mobility in China. Unlike the former analysis of the whole metropolitan or the micro community, “sub-region life circle” has its own characteristic on geographical sphere, functional element, spatial morphology and land distribution. Secondly, according to the analysis result with Binary Logistic Regression Model, the research also shows that seven factors including land-use mixed degree and bus station density impact the formation of “sub-region life circle” most, and then analyzes the index critical value of each factor. Finally, to establish a smarter “sub-region life circle”, this paper indicates that several strategies including jobs-housing fit, service cohesion and space reconstruction are the keys for its spatial organization optimization. This study expands the further understanding of cities' inner sub-region spatial structure based on human daily activity, and contributes to the theory of “life circle” in urban's meso-scale.Keywords: sub-region life circle, characteristic, formation mechanism, human activity, spatial structure
Procedia PDF Downloads 29213357 Computational Homogenization of Thin Walled Structures: On the Influence of the Global vs Local Applied Plane Stress Condition
Authors: M. Beusink, E. W. C. Coenen
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The increased application of novel structural materials, such as high grade asphalt, concrete and laminated composites, has sparked the need for a better understanding of the often complex, non-linear mechanical behavior of such materials. The effective macroscopic mechanical response is generally dependent on the applied load path. Moreover, it is also significantly influenced by the microstructure of the material, e.g. embedded fibers, voids and/or grain morphology. At present, multiscale techniques are widely adopted to assess micro-macro interactions in a numerically efficient way. Computational homogenization techniques have been successfully applied over a wide range of engineering cases, e.g. cases involving first order and second order continua, thin shells and cohesive zone models. Most of these homogenization methods rely on Representative Volume Elements (RVE), which model the relevant microstructural details in a confined volume. Imposed through kinematical constraints or boundary conditions, a RVE can be subjected to a microscopic load sequence. This provides the RVE's effective stress-strain response, which can serve as constitutive input for macroscale analyses. Simultaneously, such a study of a RVE gives insight into fine scale phenomena such as microstructural damage and its evolution. It has been reported by several authors that the type of boundary conditions applied to the RVE affect the resulting homogenized stress-strain response. As a consequence, dedicated boundary conditions have been proposed to appropriately deal with this concern. For the specific case of a planar assumption for the analyzed structure, e.g. plane strain, axisymmetric or plane stress, this assumption needs to be addressed consistently in all considered scales. Although in many multiscale studies a planar condition has been employed, the related impact on the multiscale solution has not been explicitly investigated. This work therefore focuses on the influence of the planar assumption for multiscale modeling. In particular the plane stress case is highlighted, by proposing three different implementation strategies which are compatible with a first-order computational homogenization framework. The first method consists of applying classical plane stress theory at the microscale, whereas with the second method a generalized plane stress condition is assumed at the RVE level. For the third method, the plane stress condition is applied at the macroscale by requiring that the resulting macroscopic out-of-plane forces are equal to zero. These strategies are assessed through a numerical study of a thin walled structure and the resulting effective macroscale stress-strain response is compared. It is shown that there is a clear influence of the length scale at which the planar condition is applied.Keywords: first-order computational homogenization, planar analysis, multiscale, microstrucutures
Procedia PDF Downloads 22913356 A Case Study on Quantitatively and Qualitatively Increasing Student Output by Using Available Word Processing Applications to Teach Reluctant Elementary School-Age Writers
Authors: Vivienne Cameron
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Background: Between 2010 and 2017, teachers in a suburban public school district struggled to get students to consistently produce adequate writing samples as measured by the Pennsylvania state writing rubric for measuring focus, content, organization, style, and conventions. A common thread in all of the data was the need to develop stamina in the student writers. Method: All of the teachers used the traditional writing process model (prewrite, draft, revise, edit, final copy) during writing instruction. One teacher taught the writing process using word processing and incentivizing with publication instead of the traditional pencil/paper/grading method. Students did not have instruction in typing/keyboarding. The teacher submitted resulting student work to real-life contests, magazines, and publishers. Results: Students in the test group increased both the quantity and quality of their writing over a seven month period as measured by the Pennsylvania state writing rubric. Reluctant writers, as well as students with autism spectrum disorder, benefited from this approach. This outcome was repeated consistently over a five-year period. Interpretation: Removing the burden of pencil and paper allowed students to participate in the writing process more fully. Writing with pencil and paper is physically tiring. Students are discouraged when they submit a draft and are instructed to use the Add, Remove, Move, Substitute (ARMS) method to revise their papers. Each successive version becomes shorter. Allowing students to type their papers frees them to quickly and easily make changes. The result is longer writing pieces in shorter time frames, allowing the teacher to spend more time working on individual needs. With this additional time, the teacher can concentrate on teaching focus, content, organization, style, conventions, and audience. S/he also has a larger body of works from which to work on whole group instruction such as developing effective leads. The teacher submitted the resulting student work to contests, magazines, and publishers. Although time-consuming, the submission process was an invaluable lesson for teaching about audience and tone. All students in the test sample had work accepted for publication. Students became highly motivated to succeed when their work was accepted for publication. This motivation applied to special needs students, regular education students, and gifted students.Keywords: elementary-age students, reluctant writers, teaching strategies, writing process
Procedia PDF Downloads 16913355 Study of a Cross-Flow Membrane to a Kidney Encapsulation Engineering Structures for Immunosuppression Filter
Authors: Sihyun Chae, Ryoto Arai, Waldo Concepcion, Paula Popescu
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The kidneys perform an important role in the human hormones that regulate the blood pressure, produce an active form of vitamin D and control the production of red blood cells. Kidney disease can cause health problems, such as heart disease. Also, increase the chance of having a stroke or heart attack. There are mainly to types of treatments for kidney disease, dialysis, and kidney transplant. For a better quality of life, the kidney transplant is desirable. However, kidney transplant can cause antibody reaction and patients’ body would be attacked by immune system of their own. For solving that issue, patients with transplanted kidney always take immunosuppressive drugs which can hurt kidney as side effects. Patients willing to do a kidney transplant have a waiting time of 3.6 years in average searching to find an appropriate kidney, considering there are almost 96,380 patients waiting for kidney transplant. There is a promising method to solve these issues: bioartificial kidney. Our membrane is specially designed with unique perforations capable to filter the blood cells separating the white blood cells from red blood cells. White blood cells will not pass through the encapsulated kidney preventing the immune system to attack the new organ and eliminating the need of a matching donor. It is possible to construct life-time long encapsulation without needing pumps or a power supply on the cell’s separation method preventing futures surgeries due the Cross-Channel Flow inside the device. This technology allows the possibility to use an animal kidney, prevent cancer cells to spread through the body, arm and leg transplants in the future. This project aims to improve the quality of life of patients with kidney disease.Keywords: kidney encapsulation, immunosuppression filter, leukocyte filter, leukocyte
Procedia PDF Downloads 19513354 Evaluation of the Biological Activity of New Antimicrobial and Biodegradable Textile Materials for Protective Equipment
Authors: Safa Ladhari, Alireza Saidi, Phuong Nguyen-Tri
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During health crises, such as COVID-19, using disposable protective equipment (PEs) (masks, gowns, etc.) causes long-term problems, increasing the volume of hazardous waste that must be handled safely and expensively. Therefore, producing textiles for antimicrobial and reusable materials is highly desirable to decrease the use of disposable PEs that should be treated as hazardous waste. In addition, if these items are used regularly in the workplace or for daily activities by the public, they will most likely end up in household waste. Furthermore, they may pose a high risk of contagion to waste collection workers if contaminated. Therefore, to protect the whole population in times of sanitary crisis, it is necessary to equip these materials with tools that make them resilient to the challenges of carrying out daily activities without compromising public health and the environment and without depending on them external technologies and producers. In addition, the materials frequently used for EPs are plastics of petrochemical origin. The subject of the present work is replacing petroplastics with bioplastic since it offers better biodegradability. The chosen polymer is polyhydroxybutyrate (PHB), a family of polyhydroxyalkanoates synthesized by different bacteria. It has similar properties to conventional plastics. However, it is renewable, biocompatible, and has attractive barrier properties compared to other polyesters. These characteristics make it ideal for EP protection applications. The current research topic focuses on the preparation and rapid evaluation of the biological activity of nanotechnology-based antimicrobial agents to treat textile surfaces used for PE. This work will be carried out to provide antibacterial solutions that can be transferred to a workplace application in the fight against short-term biological risks. Three main objectives are proposed during this research topic: 1) the development of suitable methods for the deposition of antibacterial agents on the surface of textiles; 2) the development of a method for measuring the antibacterial activity of the prepared textiles and 3) the study of the biodegradability of the prepared textiles. The studied textile is a non-woven fabric based on a biodegradable polymer manufactured by the electrospinning method. Indeed, nanofibers are increasingly studied due to their unique characteristics, such as high surface-to-volume ratio, improved thermal, mechanical, and electrical properties, and confinement effects. The electrospun film will be surface modified by plasma treatment and then loaded with hybrid antibacterial silver and titanium dioxide nanoparticles by the dip-coating method. This work uses simple methods with emerging technologies to fabricate nanofibers with suitable size and morphology to be used as components for protective equipment. The antibacterial agents generally used are based on silver, zinc, copper, etc. However, to our knowledge, few researchers have used hybrid nanoparticles to ensure antibacterial activity with biodegradable polymers. Also, we will exploit visible light to improve the antibacterial effectiveness of the fabric, which differs from the traditional contact mode of killing bacteria and presents an innovation of active protective equipment. Finally, this work will allow for the innovation of new antibacterial textile materials through a simple and ecological method.Keywords: protective equipment, antibacterial textile materials, biodegradable polymer, electrospinning, hybrid antibacterial nanoparticles
Procedia PDF Downloads 7513353 Affect of Reservoir Fluctuations on an Active Landslide in the Xiangjiaba Reservoir Area, Southwest China
Authors: Javed Iqbal
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Filling of Xiangjiaba Reservoir Lake in Southwest China triggered and re-activated numerous landslides due to water fluctuation. In order to understand the relationship between reservoirs and slope instability, a typical reservoir landslide (Dasha landslide) at right bank of Jinsha River was selected as a case study for in-depth investigations. The detailed field investigations were carried out in order to identify the landslide with respect to its surroundings and to find out the slip-surface. Boreholes were drilled in order to find out the subsurface lithology and the depth of failure of Dasha landslide. The in-situ geotechnical tests were performed, and the soil samples from exposed slip surface were retrieved for geotechnical laboratory analysis. Finally, stability analysis was done using 3D strength reduction method under different conditions of reservoir water level fluctuations and rainfall conditions. The in-depth investigations show that the Dasha landslide is a bedding rockslide which was once activated in 1986. The topography of Dasha landslide is relatively flat, while the back scarp and local terrain are relatively steep. The landslide area is about 29 × 104 m², and the maximum thickness of the landslide deposits revealed by drilling is about 40 m with the average thickness being about 20 m, and the volume is thus estimated being about 580 × 10⁴ m³. Bedrock in the landslide area is composed of Suining Formation of Jurassic age. The main rock type is silty mudstone with sandstone, and bedding orientation is 300~310° ∠ 7~22°. The factor of safety (FOS) of Dasha landslide obtained by 3D strength reduction cannot meet the minimum safety requirement under the working condition of reservoir level fluctuation as designed, with effect of rainfall and rapid drawdown.Keywords: Dasha landslide, Xiangjiaba reservoir, strength reduction method, bedding rockslide
Procedia PDF Downloads 15913352 Effect of Slope Angle on Gougerd Landslide Stability in Northwest of Iran
Authors: Akbar Khodavirdizadeh
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Gougerd village landslide with area about 150 hectares is located in southwest of Khoy city in northwest of the Iran. This Landslide was commenced more than 21 years and caused some damages in houses like some fissures on walls and some cracks on ground and foundations. The main mechanism of landslide is rotational with the high different of top and foot is about 230 m. The thickness of slide mass based on geoelectrical investigation is about 16m obtained. The upper layer of slope is silty sand and the lower layer of clayey gravel. In this paper, the stability of landslide are analyzed based in static analysis under different groundwater surface conditions and at slope angle changes with limit eqlibrium method and the simplified Bishop method. The results of the 72 stability analysis showed that the slope stability of Gougerd landslide increased with increasing of the groundwater surface depth of slope crown. And especially when decreased of slope angle, the safety facter more than in previous state is increased. The required of safety factor for stability in groundwater surface depth from slope crown equal 14 m and with decreased of slope angle to 3 degree at decrease of groundwater surface depth from slope crown equal 6.5 m obtained. The safety factor in critical conditions under groundwater surface depth from slope crown equal 3.5 m and at decreased of slope angle to 3 degree equal 0.5 m obtained. At groudwater surface depth from slope crown of 3 m, 7 m and 10 m respectively equal to 0.97, 1.19 and 1.33 obtained. At groudwater surface depth from slope crown of 3 m, 7 m and 10 m with decreased of slope angle to 3 degree, respectively equal to 1.27, 1.54 and 1.72 obtained. According to the results of this study, for 1 m of groundwater level decrease, the safety factor increased by 5%, and for 1 degree of reduction of the slope angle, safety factor increased by 15%. And the effect of slope angle on Gougerd landslide stability was felt more than groundwater effect.Keywords: Gougerd landslide, stability analysis, slope angle, groundwater, Khoy
Procedia PDF Downloads 16213351 Digital Transformation of Lean Production: Systematic Approach for the Determination of Digitally Pervasive Value Chains
Authors: Peter Burggräf, Matthias Dannapfel, Hanno Voet, Patrick-Benjamin Bök, Jérôme Uelpenich, Julian Hoppe
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The increasing digitalization of value chains can help companies to handle rising complexity in their processes and thereby reduce the steadily increasing planning and control effort in order to raise performance limits. Due to technological advances, companies face the challenge of smart value chains for the purpose of improvements in productivity, handling the increasing time and cost pressure and the need of individualized production. Therefore, companies need to ensure quick and flexible decisions to create self-optimizing processes and, consequently, to make their production more efficient. Lean production, as the most commonly used paradigm for complexity reduction, reaches its limits when it comes to variant flexible production and constantly changing market and environmental conditions. To lift performance limits, which are inbuilt in current value chains, new methods and tools must be applied. Digitalization provides the potential to derive these new methods and tools. However, companies lack the experience to harmonize different digital technologies. There is no practicable framework, which instructs the transformation of current value chains into digital pervasive value chains. Current research shows that a connection between lean production and digitalization exists. This link is based on factors such as people, technology and organization. In this paper, the introduced method for the determination of digitally pervasive value chains takes the factors people, technology and organization into account and extends existing approaches by a new dimension. It is the first systematic approach for the digital transformation of lean production and consists of four steps: The first step of ‘target definition’ describes the target situation and defines the depth of the analysis with regards to the inspection area and the level of detail. The second step of ‘analysis of the value chain’ verifies the lean-ability of processes and lies in a special focus on the integration capacity of digital technologies in order to raise the limits of lean production. Furthermore, the ‘digital evaluation process’ ensures the usefulness of digital adaptions regarding their practicability and their integrability into the existing production system. Finally, the method defines actions to be performed based on the evaluation process and in accordance with the target situation. As a result, the validation and optimization of the proposed method in a German company from the electronics industry shows that the digital transformation of current value chains based on lean production achieves a raise of their inbuilt performance limits.Keywords: digitalization, digital transformation, Industrie 4.0, lean production, value chain
Procedia PDF Downloads 30513350 Investigation Studies of WNbMoVTa and WNbMoVTaCr₀.₅Al Refractory High Entropy Alloys as Plasma-Facing Materials
Authors: Burçak Boztemur, Yue Xu, Laima Luo, M. Lütfi Öveçoğlu, Duygu Ağaoğulları
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Tungsten (W) is used chiefly as plasma-facing material. However, it has some problems, such as brittleness after plasma exposure. High-entropy alloys (RHEAs) are a new opportunity for this deficiency. So, the neutron shielding behavior of WNbMoVTa and WNbMoVTaCr₀.₅Al compositions were examined against He⁺ irradiation in this study. The mechanical and irradiation properties of the WNbMoVTa base composition were investigated by adding the Al and Cr elements. The mechanical alloying (MA) for 6 hours was applied to obtain RHEA powders. According to the X-ray diffraction (XRD) method, the body-centered cubic (BCC) phase and NbTa phase with a small amount of WC impurity that comes from vials and balls were determined after 6 h MA. Also, RHEA powders were consolidated with the spark plasma sintering (SPS) method (1500 ºC, 30 MPa, and 10 min). After the SPS method, (Nb,Ta)C and W₂C₀.₈₅ phases were obtained with the decomposition of WC and stearic acid that is added during MA based on XRD results. Also, the BCC phase was obtained for both samples. While the Al₂O₃ phase with a small intensity was seen for the WNbMoVTaCr₀.₅Al sample, the Ta₂VO₆ phase was determined for the base sample. These phases were observed as three different regions according to scanning electron microscopy (SEM). All elements were distributed homogeneously on the white region by measuring an electron probe micro-analyzer (EPMA) coupled with a wavelength dispersive spectroscope (WDS). Also, the grey region of the WNbMoVTa sample was rich in Ta, V, and O elements. However, the amount of Al and O elements was higher for the grey region of the WNbMoVTaCr₀.₅Al sample. The high amount of Nb, Ta, and C elements were determined for both samples. Archimedes’ densities that were measured with alcohol media were closer to the theoretical densities of RHEAs. These values were important for the microhardness and irradiation resistance of compositions. While the Vickers microhardness value of the WNbMoVTa sample was measured as ~11 GPa, this value increased to nearly 13 GPa with the WNbMoVTaCr₀.₅Al sample. These values were compatible with the wear behavior. The wear volume loss was decreased to 0.16×10⁻⁴ from 1.25×10⁻⁴ mm³ by the addition of Al and Cr elements to the WNbMoVTa. The He⁺ irradiation was conducted on the samples to observe surface damage. After irradiation, the XRD patterns were shifted to the left because of defects and dislocations. He⁺ ions were infused under the surface, so they created the lattice expansion. The peak shifting of the WNbMoVTaCr₀.₅Al sample was less than the WNbMoVTa base sample, thanks to less impact. A small amount of fuzz was observed for the base sample. This structure was removed and transformed into a wavy structure with the addition of Cr and Al elements. Also, the deformation hardening was actualized after irradiation. A lower amount of hardening was obtained with the WNbMoVTaCr₀.₅Al sample based on the changing microhardness values. The surface deformation was decreased in the WNbMoVTaCr₀.₅Al sample.Keywords: refractory high entropy alloy, microhardness, wear resistance, He⁺ irradiation
Procedia PDF Downloads 6413349 Characterization of Tailings From Traditional Panning of Alluvial Gold Ore (A Case Study of Ilesa - Southwestern Nigeria Goldfield Tailings Dumps)
Authors: Olaniyi Awe, Adelana R. Adetunji, Abraham Adeleke
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Field observation revealed a lot of artisanal gold mining activities in Ilesa gold belt of southwestern Nigeria. The possibility of alluvial and lode gold deposits in commercial quantities around this location is very high, as there are many resident artisanal gold miners who have been mining and trading alluvial gold ore for decades and to date in the area. Their major process of solid gold recovery from its ore is by gravity concentration using the convectional panning method. This method is simple to learn and fast to recover gold from its alluvial ore, but its effectiveness is based on rules of thumb and the artisanal miners' experience in handling gold ore panning tool while processing the ore. Research samples from five alluvial gold ore tailings dumps were collected and studied. Samples were subjected to particle size analysis and mineralogical and elemental characterization using X-Ray Diffraction (XRD) and Particle-Induced X-ray Emission (PIXE) methods, respectively. The results showed that the tailings were of major quartz in association with albite, plagioclase, mica, gold, calcite and sulphide minerals. The elemental composition analysis revealed a 15ppm of gold concentration in particle size fraction of -90 microns in one of the tailings dumps investigated. These results are significant. It is recommended that heaps of panning tailings should be further reprocessed using other gold recovery methods such as shaking tables, flotation and controlled cyanidation that can efficiently recover fine gold particles that were previously lost into the gold panning tailings. The tailings site should also be well controlled and monitored so that these heavy minerals do not find their way into surrounding water streams and rivers, thereby causing health hazards.Keywords: gold ore, panning, PIXE, tailings, XRD
Procedia PDF Downloads 8413348 Vibration Control of a Horizontally Supported Rotor System by Using a Radial Active Magnetic Bearing
Authors: Vishnu A., Ashesh Saha
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The operation of high-speed rotating machinery in industries is accompanied by rotor vibrations due to many factors. One of the primary instability mechanisms in a rotor system is the centrifugal force induced due to the eccentricity of the center of mass away from the center of rotation. These unwanted vibrations may lead to catastrophic fatigue failure. So, there is a need to control these rotor vibrations. In this work, control of rotor vibrations by using a 4-pole Radial Active Magnetic Bearing (RAMB) as an actuator is analysed. A continuous rotor system model is considered for the analysis. Several important factors, like the gyroscopic effect and rotary inertia of the shaft and disc, are incorporated into this model. The large deflection of the shaft and the restriction to axial motion of the shaft at the bearings result in nonlinearities in the system governing equation. The rotor system is modeled in such a way that the system dynamics can be related to the geometric and material properties of the shaft and disc. The mathematical model of the rotor system is developed by incorporating the control forces generated by the RAMB. A simple PD controller is used for the attenuation of system vibrations. An analytical expression for the amplitude and phase equations is derived using the Method of Multiple Scales (MMS). Analytical results are verified with the numerical results obtained using an ‘ode’ solver in-built into MATLAB Software. The control force is found to be effective in attenuating the system vibrations. The multi-valued solutions leading to the jump phenomenon are also eliminated with a proper choice of control gains. Most interestingly, the shape of the backbone curves can also be altered for certain values of control parameters.Keywords: rotor dynamics, continuous rotor system model, active magnetic bearing, PD controller, method of multiple scales, backbone curve
Procedia PDF Downloads 7513347 Studies on the Use of Sewage Sludge in Agriculture or in Incinerators
Authors: Catalina Iticescu, Lucian Georgescu, Mihaela Timofti, Dumitru Dima, Gabriel Murariu
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The amounts of sludge resulting from the treatment of domestic and industrial wastewater can create serious environmental problems if no solutions are found to eliminate them. At present, the predominant method of sewage sludge disposal is to store and use them in agricultural applications. The sewage sludge has fertilizer properties and can be used to enrich agricultural soils due to the nutrient content. In addition to plant growth (nitrogen and phosphorus), the sludge also contains heavy metals in varying amounts. An increasingly used method is the incineration of sludge. Thermal processes can be used to convert large amounts of sludge into useful energy. The sewage sludge analyzed for the present paper was extracted from the Wastewater Treatment Station (WWTP) Galati, Romania. The physico-chemical parameters determined were: pH (upH), nutrients and heavy metals. The determination methods were electrochemical, spectrophotometric and energy dispersive X–ray analyses (EDX). The results of the tests made on the content of nutrients in the sewage sludge have shown that existing nutrients can be used to increase the fertility of agricultural soils. The conclusion reached was that these sludge can be safely used on agricultural land and with good agricultural productivity results. To be able to use sewage sludge as a fuel, we need to know its calorific values. For wet sludge, the caloric power is low, while for dry sludge it is high. Higher calorific value and lower calorific value are determined only for dry solids. The apparatus used to determine the calorific power was a Parr 6755 Solution Calorimeter Calorimeter (Parr Instrument Company USA 2010 model). The calorific capacities for the studied sludge indicate that they can be used successfully in incinerators. Mixed with coal, they can also be used to produce electricity. The advantages are: it reduces the cost of obtaining electricity and considerably reduces the amount of sewage sludge.Keywords: agriculture, incinerators, properties, sewage sludge
Procedia PDF Downloads 16613346 Religion and Democracy: Assessing Tolerance in the Diversity of Indonesia
Authors: Harsi Nastiti, Haidar Fikri
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Indonesia has been known for its diversity of cultures, ethnics, religions, and races. This diversity signs as the uniqueness of the country, so tolerance becomes vital point here. As a unitary state, tolerance value is established strongly as the foundation of democracy implementation but recently this tolerance condition facing up some problems after regional election. In this case, religion issue takes a main role for the Indonesian political system which is managed into tolerance breaker especially for local democracy. The election of Jakarta’s Governor 2017 can be said as the momentum for the people to rethink the democracy and tolerance meaning. It begins from one of the governor candidates who makes statement about the majority religion and unfortunately the candidate comes from the minority. The statement emerges into a new social movement based on religiosity. Basically, the social movement which is coordinated by Islamic Defender Front (Front Pembela Islam or FPI) and National Movement to Safeguard the Fatwa-Indonesian Ulama Council (GNPF-MUI) want to demand the justice in the name of blasphemy. The action continuously happens in different names (Action 411, 212, etc.). So, this article analyzes the new phenomenon and how does the impact for the tolerance and democracy life in Indonesia. The method is using qualitative method by review of literature and media content analysis. Results show this phenomenon potentially spreading new conflicts far beyond the goal of the action itself; justice. It makes the conflicts more complex after there are actions such as; Parade Kebhinekaan and Aksi Lilin which contrary reacts to the actions before. These actions and reactions rise up the sensitive issues for Indonesia like religions, Pancasila, unity in diversity, ethnics, and races. At the same time raising skepticism; will it be over after the candidate is getting sentenced or becomes the dangerous latent conflict that will threaten tolerance and democracy in Indonesia.Keywords: conflict, democracy, religion, tolerance
Procedia PDF Downloads 28413345 Duplex Real-Time Loop-Mediated Isothermal Amplification Assay for Simultaneous Detection of Beef and Pork
Authors: Mi-Ju Kim, Hae-Yeong Kim
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Product mislabeling and adulteration have been increasing the concerns in processed meat products. Relatively inexpensive pork meat compared to meat such as beef was adulterated for economic benefit. These food fraud incidents related to pork were concerned due to economic, religious and health reasons. In this study, a rapid on-site detection method using loop-mediated isothermal amplification (LAMP) was developed for the simultaneous identification of beef and pork. Each specific LAMP primer for beef and pork was designed targeting on mitochondrial D-loop region. The LAMP assay reaction was performed at 65 ℃ for 40 min. The specificity of each primer for beef and pork was evaluated using DNAs extracted from 13 animal species including beef and pork. The sensitivity of duplex LAMP assay was examined by serial dilution of beef and pork DNAs, and reference binary mixtures. This assay was applied to processed meat products including beef and pork meat for monitoring. Each set of primers amplified only the targeted species with no cross-reactivity with animal species. The limit of detection of duplex real-time LAMP was 1 pg for each DNA of beef and pork and 1% pork in a beef-meat mixture. Commercial meat products that declared the presence of beef and/or pork meat on the label showed positive results for those species. This method was successfully applied to detect simultaneous beef and pork meats in processed meat products. The optimized duplex LAMP assay can identify simultaneously beef and pork meat within less than 40 min. A portable real-time fluorescence device used in this study is applicable for on-site detection of beef and pork in processed meat products. Thus, this developed assay was considered to be an efficient tool for monitoring meat products.Keywords: beef, duplex real-time LAMP, meat identification, pork
Procedia PDF Downloads 21513344 Impacts of Oil Palm Plantation on Mammal and Herpetofauna Diversity: A Case Study in Riau Province, Indonesia
Authors: Yanto Santosa, Yohanna Dalimunthe, Intan Purnamasari
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Expansion of Indonesia oil palm plantations has contributed significantly to the national revenue annually and has been able to absorb millions of workers. Behind all these positive contributions, such expansion was accused as the cause of the decline in wildlife populations such as mammal and herpetofauna. Research was carried out in 8 oil palm plantations in Riau Province of Indonesia from March to April 2016, to determine the impacts of oil palm plantations on mammal and herpetofauna biodiversity. Direct observation was conducted simultaneously equipped with camera traps placed (for mammal) on various land cover types. For mammals' survey, line transect method was used, and for herpetofauna, Visual Encounter Survey (VES) method was used. Landsat imagery was used to interpret land cover types 3 years prior to the establishment of the oil palm plantations. The study revealed that one year before the oil palm plantations was established, most the land covers were comprised of 49.96% rubber plantations, 35.99% secondary forest, 10.17% bare land, 3.03% shrubs and 0.84% mixed dryland farming-shrubs. Based on the number of species found, it was identified that on the average, mammal diversity in 4 of 8 oil palm plantations, showed a decrease by 14.29%-100%, whereas 2 plantations did not experienced any changes in the number of species and one plantation showed an increased in the number of mammal species. The plantations that experienced a reduction in the number of mammal’s diversity were previously dominated covered by secondary forest (40%) and rubber plantation (40%), while those experiencing no changes in the number of species were also dominated by secondary forest. The area with an increased number of mammal species was historically dominated by rubber plantation. On the contrary, significant results were shown for herpetofauna, where all study sites showed a sharp increase in the number of herpetofauna species, by 100%-225.00%.Keywords: herpetofauna, impact, mammal, oil palm plantations
Procedia PDF Downloads 23013343 Probiotic Antibacterial Test of Pediococcus pentosaceus Isolated from Dadih in Inhibiting Periodontitis Bacteria: In Vitro Study on Bacteria Aggregatibacter actinomycetemcomitans
Authors: Nurlaili Syafar Wulan, Almurdi, Suprianto Kosno
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Introduction: Periodontitis defined as an inflammatory disease of teeth supporting tissue with irritation of specific pathogens as the main aetiology. Periodontitis can be cured by giving medical action accompanied by administration of an antibiotic, but the use of antibiotic has a side effect that can cause bacterial resistance. This side effect can be corrected by probiotic, which has antibiotic-like substance but do not have bacterial resistance effect; it makes probiotic became a promising future periodontitis medication. West Sumatran people has their own typical traditional food product made from fermented buffalo’s milk called dadih, and it contained probiotics. Objectives: The aim of this study was to determine the ability of probiotic Pediococcus pentosaceus isolated from dadih in inhibiting the growth of bacteria Aggregatibacter actinomycetemcomitans. Material and Method: This was a true experimental study with post-test and control group design. This study was conducted on 36 samples of 2 treatment groups, the test group with probiotic Pediococcus pentosacesus isolated from dadih and the negative control group with sterile aquadest. The antibacterial effect was tested using the Kirby-Bauer disk diffusion method and calculated by measuring the zone of inhibition on MHA around paper disk using a sliding caliper with 0.5 mm accuracy. Result: The result of bivariate analysis using Independent t-test was p=0.00 where p < 0.05 means that there is a significant difference between the tested group and negative control group. Conclusion: Probiotic Pediococcus pentosaceus isolated from dadih are able to inhibit the growth of Aggregatibacter actinomycetemcomitans.Keywords: aggregatibacter actinomycetemcomitans, antibacterial activities, periodontitis, probiotic Pediococcus pentosaceus
Procedia PDF Downloads 12813342 Development of an Autonomous Automated Guided Vehicle with Robot Manipulator under Robot Operation System Architecture
Authors: Jinsiang Shaw, Sheng-Xiang Xu
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This paper presents the development of an autonomous automated guided vehicle (AGV) with a robot arm attached on top of it within the framework of robot operation system (ROS). ROS can provide libraries and tools, including hardware abstraction, device drivers, libraries, visualizers, message-passing, package management, etc. For this reason, this AGV can provide automatic navigation and parts transportation and pick-and-place task using robot arm for typical industrial production line use. More specifically, this AGV will be controlled by an on-board host computer running ROS software. Command signals for vehicle and robot arm control and measurement signals from various sensors are transferred to respective microcontrollers. Users can operate the AGV remotely through the TCP / IP protocol and perform SLAM (Simultaneous Localization and Mapping). An RGBD camera and LIDAR sensors are installed on the AGV, using these data to perceive the environment. For SLAM, Gmapping is used to construct the environment map by Rao-Blackwellized particle filter; and AMCL method (Adaptive Monte Carlo localization) is employed for mobile robot localization. In addition, current AGV position and orientation can be visualized by ROS toolkit. As for robot navigation and obstacle avoidance, A* for global path planning and dynamic window approach for local planning are implemented. The developed ROS AGV with a robot arm on it has been experimented in the university factory. A 2-D and 3-D map of the factory were successfully constructed by the SLAM method. Base on this map, robot navigation through the factory with and without dynamic obstacles are shown to perform well. Finally, pick-and-place of parts using robot arm and ensuing delivery in the factory by the mobile robot are also accomplished.Keywords: automated guided vehicle, navigation, robot operation system, Simultaneous Localization and Mapping
Procedia PDF Downloads 14013341 Canopy Temperature Acquired from Daytime and Nighttime Aerial Data as an Indicator of Trees’ Health Status
Authors: Agata Zakrzewska, Dominik Kopeć, Adrian Ochtyra
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The growing number of new cameras, sensors, and research methods allow for a broader application of thermal data in remote sensing vegetation studies. The aim of this research was to check whether it is possible to use thermal infrared data with a spectral range (3.6-4.9 μm) obtained during the day and the night to assess the health condition of selected species of deciduous trees in an urban environment. For this purpose, research was carried out in the city center of Warsaw (Poland) in 2020. During the airborne data acquisition, thermal data, laser scanning, and orthophoto map images were collected. Synchronously with airborne data, ground reference data were obtained for 617 studied species (Acer platanoides, Acer pseudoplatanus, Aesculus hippocastanum, Tilia cordata, and Tilia × euchlora) in different health condition states. The results were as follows: (i) healthy trees are cooler than trees in poor condition and dying both in the daytime and nighttime data; (ii) the difference in the canopy temperatures between healthy and dying trees was 1.06oC of mean value on the nighttime data and 3.28oC of mean value on the daytime data; (iii) condition classes significantly differentiate on both daytime and nighttime thermal data, but only on daytime data all condition classes differed statistically significantly from each other. In conclusion, the aerial thermal data can be considered as an alternative to hyperspectral data, a method of assessing the health condition of trees in an urban environment. Especially data obtained during the day, which can differentiate condition classes better than data obtained at night. The method based on thermal infrared and laser scanning data fusion could be a quick and efficient solution for identifying trees in poor health that should be visually checked in the field.Keywords: middle wave infrared, thermal imagery, tree discoloration, urban trees
Procedia PDF Downloads 10913340 Analysis of the Behavior of the Structure Under Internal Anfo Explosion
Authors: Seung-Min Ko, Seung-Jai Choi, Gun Jung, Jang-Ho Jay Kim
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Although extensive explosion-related research has been performed in the past several decades, almost no research has focused on internal blasts. However, internal blast research is needed to understand about the behavior of a containment structure or building under internal blast loading, as in the case of the Chornobyl and Fukushima nuclear accidents. Therefore, the internal blast study concentrated on RC and PSC structures is performed. The test data obtained from reinforced concrete (RC) and prestressed concrete (PSC) tubular structures applied with an internal explosion using ammonium nitrate/fuel oil (ANFO) charge are used to assess their deformation resistance and ultimate failure load based on the structural stiffness change under various charge weight. For the internal blast charge weight, ANFO explosive charge weights of 15.88, 20.41, 22.68 and 24.95 kg were selected for the RC tubular structures, and 22.68, 24.95, 27.22, 29.48, and 31.75 kg were selected for PSC tubular structures, which were detonated at the center of cross section at the mid-span with a standoff distance of 1,000mm to the inner wall surface. Then, the test data were used to predict the internal charge weight required to fail a real scale reinforced concrete containment vessels (RCCV) and prestressed concrete containment vessel (PCCV). Then, the analytical results based on the experimental data were derived using the simple assumptions of the models, and another approach using the stiffness, deformation and explosion weight relationship was used to formulate a general method for analyzing internal blasted tubular structures. A model of the internal explosion of a steel tube was used as an example for validation. The proposed method can be used generically, using factors according to the material characteristics of the target structures. The results of the study are discussed in detail in the paper.Keywords: internal blast, reinforced concrete, RCCV, PCCV, stiffness, blast safety
Procedia PDF Downloads 6813339 An Active Subsurface Geological Structure Pattern of Mud Volcano Phenomenon as an Environmental Impact of Petroleum Withdrawal in Sidoarjo, East Java, Indonesia
Authors: M. M. S. Prahastomi, M. Muhajir Saputra, Axel Derian
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Lapindo mud (LUSI ) phenomenon which occurred in Sidoarjo 2006 is a national scale of the geological phenomenon. This mudflow forms a mud volcano that spreads by time is in the need of serious treatment. Some further research has been conducted either by the application method of geodesy, geophysics, and subsurface geology, but still remains a mystery to this phenomenon. Sidoarjo Physiographic regions are included in the Kendeng zone flanked by Rembang zones in northern and Solo zones in southern. In this region revealed Kabuh formation, Jombang formation, and alluvium. In general, in the northern part of the area is composed of sedimentary rocks Sidoarjo klastika, epiklastic, pyroclastics, and older alluvium of the Early Pleistocene to Resen. The study was conducted with the literature study of the stratigraphy and regional geology as well as secondary data from observations coupled gravity method (Anomaly Bouger). The aim of the study is to reveal the subsurface geology structure pattern and the changes in mass flow. Gravity anomaly data were obtained from the calculation of the value of gravity and altitude, then processed into gravity anomaly contours which reflect changes in density of each group observed gravity. The gravity data could indicate a bottom surface which deformation occur the stronger or more intense to the south. Deformation in the form of gravity impairment was associated with a decrease in future density which is indicated by the presence of gas, water and gas bursts. Sectional analysis of changes in the measured value of gravity at different times indicates a change in the value of gravity caused by the presence of subsurface subsidence. While the gravity anomaly section describes the fault zone causes the zone to be unstable.Keywords: mud volcano, Lumpur Sidoarjo, Bouger anomaly, Indonesia
Procedia PDF Downloads 46313338 Elastic Collisions of Electrons with DNA and Water From 10 eV to 100 KeV: Scar Macro Investigation
Authors: Aouina Nabila Yasmina, Zine El Abidine Chaoui
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Recently, understanding the interactions of electrons with the DNA molecule and its components has attracted considerable interest because DNA is the main site damaged by ionizing radiation. The interactions of radiation with DNA induce a variety of molecular damage such as single-strand breaks, double-strand breaks, basic damage, cross-links between proteins and DNA, and others, or the formation of free radicals, which, by chemical reactions with DNA, can also lead to breakage of the strand. One factor that can contribute significantly to these processes is the effect of water hydration on the formation and reaction of radiation induced by these radicals in and / or around DNA. B-DNA requires about 30% by weight of water to maintain its native conformation in the crystalline state. The transformation depends on various factors such as sequence, ion composition, concentration and water activity. Partial dehydration converts it to DNA-A. The present study shows the results of theoretical calculations for positrons and electrons elastic scattering with DNA medium and water over a broad energy range from 10 eV to 100 keV. Indeed, electron elastic cross sections and elastic mean free paths are calculated using a corrected form of the independent atom method, taking into account the geometry of the biomolecule (SCAR macro). Moreover, the elastic scattering of electrons and positrons by atoms of the biomolecule was evaluated by means of relativistic (Dirac) partial wave analysis. Our calculated results are compared with theoretical data available in the literature in the absence of experimental data, in particular for positron. As a central result, our electron elastic cross sections are in good agreement with existing theoretical data in the range of 10 eV to 1 keV.Keywords: elastic cross scrion, elastic mean free path, scar macro method, electron collision
Procedia PDF Downloads 5713337 Designing an Exhaust Gas Energy Recovery Module Following Measurements Performed under Real Operating Conditions
Authors: Jerzy Merkisz, Pawel Fuc, Piotr Lijewski, Andrzej Ziolkowski, Pawel Czarkowski
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The paper presents preliminary results of the development of an automotive exhaust gas energy recovery module. The aim of the performed analyses was to select the geometry of the heat exchanger that would ensure the highest possible transfer of heat at minimum heat flow losses. The starting point for the analyses was a straight portion of a pipe, from which the exhaust system of the tested vehicle was made. The design of the heat exchanger had a cylindrical cross-section, was 300 mm long and was fitted with a diffuser and a confusor. The model works were performed for the mentioned geometry utilizing the finite volume method based on the Ansys CFX v12.1 and v14 software. This method consisted in dividing of the system into small control volumes for which the exhaust gas velocity and pressure calculations were performed using the Navier-Stockes equations. The heat exchange in the system was modeled based on the enthalpy balance. The temperature growth resulting from the acting viscosity was not taken into account. The heat transfer on the fluid/solid boundary in the wall layer with the turbulent flow was done based on an arbitrarily adopted dimensionless temperature. The boundary conditions adopted in the analyses included the convective condition of heat transfer on the outer surface of the heat exchanger and the mass flow and temperature of the exhaust gas at the inlet. The mass flow and temperature of the exhaust gas were assumed based on the measurements performed in actual traffic using portable PEMS analyzers. The research object was a passenger vehicle fitted with a 1.9 dm3 85 kW diesel engine. The tests were performed in city traffic conditions.Keywords: waste heat recovery, heat exchanger, CFD simulation, pems
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