Search results for: weak ground
1822 Fluidized-Bed Combustion of Biomass with Elevated Alkali Content: A Comparative Study between Two Alternative Bed Materials
Authors: P. Ninduangdee, V. I. Kuprianov
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Palm kernel shell is an important bioenergy resource in Thailand. However, due to elevated alkali content in biomass ash, this oil palm residue shows high tendency to bed agglomeration in a fluidized-bed combustion system using conventional bed material (silica sand). In this study, palm kernel shell was burned in the conical fluidized-bed combustor (FBC) using alumina and dolomite as alternative bed materials to prevent bed agglomeration. For each bed material, the combustion tests were performed at 45kg/h fuel feed rate with excess air within 20–80%. Experimental results revealed rather weak effects of the bed material type but substantial influence of excess air on the behaviour of temperature, O2, CO, CxHy, and NO inside the reactor, as well as on the combustion efficiency and major gaseous emissions of the conical FBC. The optimal level of excess air ensuring high combustion efficiency (about 98.5%) and acceptable level of the emissions was found to be about 40% when using alumina and 60% with dolomite. By using these alternative bed materials, bed agglomeration can be prevented when burning the shell in the proposed conical FBC. However, both bed materials exhibited significant changes in their morphological, physical and chemical properties in the course of the time.Keywords: palm kernel shell, fluidized-bed combustion, alternative bed materials, combustion and emission performance, bed agglomeration prevention
Procedia PDF Downloads 2431821 New Opportunities in Business as a Result of the Corona Virus
Authors: Lasha Kamashidze
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COVID19 has already become one of the biggest challenges in the modern world. The virus has also had a significant impact on the world economy, which has faced a major crisis. Each crisis and challenge creates new opportunities. Changes in the world have allowed us to see business in a new light. The aim of the article is to explore new opportunities in the business that have arisen as a result of the Corona virus. Now, organizations with a service profile are working to meet the rapidly changing needs of their staff and customers. Due to the situation created by the pandemic, it became necessary to make some changes in people's daily lives. It became necessary to adapt to the new reality. The changes caused by Coronavirus require in-depth research and analysis in the world economy, as the current situation is not ruled out to be repeated in the future. Many companies have resorted to remote work methods, which require organizational changes. The form of remote work is not new to the Georgian reality. In Georgia, as well as in the rest of the world, the business sector has undergone changes. It will be beneficial for many Georgian companies to make organizational changes that will allow them to work remotely. The current situation has shown the managers of both Georgian and other companies to have "weak points" in organizing modern business. A survey was conducted (online survey), as a result of which it received important information about the problems of remote work in Georgia.Keywords: organizational change, coronomics, remote work, management
Procedia PDF Downloads 781820 A General Strategy for Noise Assessment in Open Mining Industries
Authors: Diego Mauricio Murillo Gomez, Enney Leon Gonzalez Ramirez, Hugo Piedrahita, Jairo Yate
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This paper proposes a methodology for the management of noise in open mining industries based on an integral concept, which takes into consideration occupational and environmental noise as a whole. The approach relies on the characterization of sources, the combination of several measurements’ techniques and the use of acoustic prediction software. A discussion about the difference between frequently used acoustic indicators such as Leq and LAV is carried out, aiming to establish common ground for homologation. The results show that the correct integration of this data not only allows for a more robust technical analysis but also for a more strategic route of intervention as several departments of the company are working together. Noise control measurements can be designed to provide a healthy acoustic surrounding in which the exposure workers but also the outdoor community is benefited.Keywords: environmental noise, noise control, occupational noise, open mining
Procedia PDF Downloads 2561819 White Clover Trifolium repens L. Genetic Diversity and Salt Tolerance in Urban Area of Riga
Authors: Dace Grauda, Gunta Cekstere, Inta Belogrudova, Andis Karlsons, Isaak Rashal
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Trifolium repens L. (white or Dutch clover) is a perennial herb, belongs to legume family (Leguminosae Juss.), spread extensively by stolons and seeds. The species is cultivated worldwide and was naturalized in many countries in meadows, yards, gardens, along roads and streets etc., especially in temperate regions. It is widespread also in grasslands throughout Riga, the capital of Latvia. The goal of this study was to investigate genetic structure of white clover population in Riga and to evaluate influence of different salt concentration on plants. For this purpose universal retrotranspozone based IRAP (Inter-Retrotransposon Amplified Polymorphism) method was used. The plant material was collected in different regions of Riga and in several urban areas of Latvia. Plant DNA was isolated from in silicogel dried leaves of using 1% CTAB (cetyltrimet-ammonium bromide) buffer DNA extraction procedure. Genetic structure of city population and wild populations were compared. Soil salinization is an important issue associated with low water resources and highly urbanized areas in aride and semi-aride climate conditions, as well as de-icing salt application to prevent ice formation on roads in winter. The T. repens variety ‘Daile’ (form giganteum), one of the often used component of urban greeneries, was studied in this investigation. Plants were grown from seeds and cultivated in the light conditions (18-25 C, 16h/8h of day/night, light intensity 3000 lx) in plastic pots (200 ml), filled with commercial neutralized (pH 5.9 ± 0.3) peat substrate with mineral nutrients. To analyse the impact of increased soil salinity treatments with gradually rising NaCl (0; 20; 40; 60; 80; 100 mM) levels were arranged. Plants were watered when necessary with deionised water to provide optimum substrate moisture 60-70%. The experiment was terminated six weeks after establishment. For analysis of mineral nutrients, dry plant material (above ground part and roots) was used. Decrease of Na content can be significant under elevated salinity till 20 mM NaCl. High NaCl concentrations in the substrate increase Na, Cl, Cu, Fe, and Mn accumulation, but reduce S, Mg, K content in the plant above ground parts. Abiotic stresses generally changes the levels of DNA metilation. Several candidate gene for salt tolerance will be analysed for DNA metilation level using Pyromark-Q24 advanced.Keywords: DNA metilation, IRAP, soil salinization, white clover
Procedia PDF Downloads 3581818 Detentions in Kashmir: A Review of Impact of J&K PSA, 1978
Authors: Naseer Ahmad Bhat
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Jammu and Kashmir Public Safety Act, 1978 provides for administrative detention in Jammu and Kashmir, a disputed region between India & Pakistan, since 1947. This paper shall critically analyse the working of PSA (Public Safety Act) in this J&K since 1978, since its inception. Detentions under this Act traverse between the security of the State and Liberty of citizens but over decades, has this Act served its purpose in Kashmir or not shall be analysed in this paper. J&K PSA is used to detain political workers, Over-Ground Workers and Stone Pelters who pose a direct threat to the ‘security of the State.’ Detentions under J&K PSA are a good measure in the hands of Security agencies to bring calm during periods of turmoil, but it has socio-economic consequences for detainees as well as families. This paper shall highlight the Socio-Economic impact of detentions under J&K PSA on individuals and families.Keywords: detentions, Kashmir, public safety act, liberty, security
Procedia PDF Downloads 2201817 ELD79-LGD2006 Transformation Techniques Implementation and Accuracy Comparison in Tripoli Area, Libya
Authors: Jamal A. Gledan, Othman A. Azzeidani
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During the last decade, Libya established a new Geodetic Datum called Libyan Geodetic Datum 2006 (LGD 2006) by using GPS, whereas the ground traversing method was used to establish the last Libyan datum which was called the Europe Libyan Datum 79 (ELD79). The current research paper introduces ELD79 to LGD2006 coordinate transformation technique, the accurate comparison of transformation between multiple regression equations and the three-parameters model (Bursa-Wolf). The results had been obtained show that the overall accuracy of stepwise multi regression equations is better than that can be determined by using Bursa-Wolf transformation model.Keywords: geodetic datum, horizontal control points, traditional similarity transformation model, unconventional transformation techniques
Procedia PDF Downloads 2981816 Explanation of the Electron Transfer Mechanism from β-Carotene to N-Pentyl Peroxyl Radical by Density Functional Theory Method
Authors: E. Esra Kasapbaşı, Büşra Yıldırım
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Weak oxidizing radicals, such as alkyl peroxyl derivatives, react with carotenoids through hydrogen atom transfer to form neutral carotenoid radicals. Using the DFT method, it has been observed that s-cis-β-carotene is more stable than all-transforms. In the context of this study, an attempt is made to explain the reaction mechanism of the isomers of β-carotene, which exhibits antioxidant properties, with n-pentyl peroxide, one of the alkyl peroxyl molecules, using the Density Functional Theory (DFT) method. The cis and transforms of β-carotene are used in the study to determine which form is more reactive. For this purpose, Natural Bond Orbital (NBO) charges of all optimized structures are calculated, and electron transfer is determined by examining electron transitions between Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO). Additionally, the radical character and reaction mechanism of β-carotene in a radical environment are attempted to be explained based on the calculations. The theoretical inclination of whether β-carotene in cis or transforms is more active in reaction is also discussed. All these calculations are performed in the gas phase using the Integral Equation Formalism Polarizable Continuum Model IEFPCM method with dichloromethane as the solvent.Keywords: β-carotene, n-pentyl peroxyl radical, DFT, TD-DFT
Procedia PDF Downloads 721815 The Grinding Influence on the Strength of Fan-Out Wafer-Level Packages
Authors: Z. W. Zhong, C. Xu, W. K. Choi
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To build a thin fan-out wafer-level package, the package had to be ground to a thin level. In this work, the influence of the grinding processes on the strength of the fan-out wafer-level packages was investigated. After different grinding processes, all specimens were placed on a three-point-bending fixture installed on a universal tester for three-point-bending testing, and the strength of the fan-out wafer-level packages was measured. The experiments revealed that the average flexure strength increased with the decreasing surface roughness height of the fan-out wafer-level package tested. The grinding processes had a significant influence on the strength of the fan-out wafer-level packages investigated.Keywords: FOWLP strength, surface roughness, three-point bending, grinding
Procedia PDF Downloads 2741814 Analysis of Reinforced Granular Pile in Soft Soil
Authors: G. Nitesh
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Stone column or granular pile is a proven technique to mitigate settlement in soft soil. Granular pile increases both rate of consolidation and stiffness of the ground. In this paper, a method to analyze further reduction in settlement of granular column reinforced with lime pile is presented treating the system as a unit cell and considering one-dimensional compression approach. The core of the granular pile is stiffened with a steel rod or lime column. Influence of a wide range of parameters such as area ratio of granular pile-soft soil, area ratio of lime pile-granular pile, modular ratio of granular pile and modular ratio of lime pile with respect to granular pile on settlement reduction factor, etc. are obtained and presented.Keywords: lime pile, granular pile, soft soil, settlement
Procedia PDF Downloads 3991813 Coping with Geological Hazards during Construction of Hydroelectric Projects in Himalaya
Authors: B. D. Patni, Ashwani Jain, Arindom Chakraborty
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The world’s highest mountain range has been forming since the collision of Indian Plate with Asian Plate 40-50 million years ago. The Indian subcontinent has been deeper and deeper in to the rest of Asia resulting upliftment of Himalaya & Tibetan Plateau. The complex domain has become a major challenge for construction of hydro electric projects. The Himalayas are geologically complex & seismically active. Shifting of Indian Plate northwardly and increasing the amount of stresses in the fragile domain which leads to deformation in the form of several fold, faults and upliftment. It is difficult to undergo extensive geological investigation to ascertain the geological problems to be encountered during construction. Inaccessibility of the terrain, high rock cover, unpredictable ground water condition etc. are the main constraints. The hydroelectric projects located in Himalayas have faced many geological and geo-hydrological problems while construction of surface and subsurface works. Based on the experience, efforts have been made to identify the expected geological problems during and after construction of the projects. These have been classified into surface and subsurface problems which include existence of inhomogeneous deep overburden in the river bed or buried valley, abrupt change in bed rock profile, Occurrences of fault zones/shear zones/fractured rock in dam foundation and slope instability in the abutments. The tunneling difficulties are many such as squeezing ground condition, popping, rock bursting, high temperature gradient, heavy ingress of water, existence of shear seams/shear zones and emission of obnoxious gases. However, these problems were mitigated by adopting suitable remedial measures as per site requirement. The support system includes shotcrete, wire mesh, rock bolts, steel ribs, fore-poling, pre-grouting, pipe-roofing, MAI anchors, toe wall, retaining walls, reinforced concrete dowels, drainage drifts, anchorage cum drainage shafts, soil nails, concrete cladding and shear keys. Controlled drilling & blasting, heading & benching, proper drainage network and ventilation system are other remedial measures adopted to overcome such adverse situations. The paper highlights the geological uncertainties and its remedial measures in Himalaya, based on the analysis and evaluation of 20 hydroelectric projects during construction.Keywords: geological problems, shear seams, slope, drilling & blasting, shear zones
Procedia PDF Downloads 3981812 Support of Syrian Refugees: The Roles of Descriptive and Injunctive Norms, Perception of Threat, and Negative Emotions
Authors: Senay Yitmen
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This research investigated individual’s support and helping intentions towards Syrian refugees in Turkey. This is examined in relation to perceived threat and negative emotions, and also to the perceptions of whether one’s intimate social network (family and friends) considers Syrians a threat (descriptive network norm) and whether this network morally supports Syrian refugees (injunctive norms). A questionnaire study was conducted among Turkish participants (n= 565) and the results showed that perception of threat was associated with negative emotions which, in turn, were related to less support of Syrian refugees. Additionally, descriptive norms moderated the relationship between perceived threat and negative emotions towards Syrian refugees. Furthermore, injunctive norms moderated the relationship between negative emotions and support to Syrian refugees. Specifically, the findings indicate that perceived threat is associated with less support of Syrian refugees through negative emotions when descriptive norms are weak and injunctive norms are strong. Injunctive norms appear to trigger a dilemma over the decision to conform or not to conform: when one has negative emotions as a result of perceived threat, it becomes more difficult to conform to the moral obligation of injunctive norms which is associated with less support of Syrian refugees. Hence, these findings demonstrate that both descriptive and injunctive norms are important and play different roles in individual’s support of Syrian refugees.Keywords: descriptive norms, emotions, injunctive norms, the perception of threat
Procedia PDF Downloads 1831811 Pharmacognostical and Phytochemical Investigation of the Endemic Medicinal Plant Tekchebilium arvensis Linn
Authors: K. Bengango, H. Mesahsah, F. Haseb-Reho, J. M. Tafrate
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This present work was conducted to explore the micro-morphology and phytochemical characterization of the endemic medicinal plant Tekchebilium arvensis Linn (Asteraceae). Macroscopy, microscopy, physicochemical analysis and WHO recommended parameters for standardizations were performed. Microscopic evaluation revealed the presence of abaxial epidermis with paracytic stomata. Petiole showed epidermis, vascular strands, ground tissue and secretary cavities. Physico-chemical tests like ash values, loss on drying, extractive values were determined. Preliminary phytochemical screening showed the presence of sterols, tannins, flavonoids, glycosides, volatile oil, terpenoids, saponin and alkaloids.Keywords: Tekchebilium arvensis Linn, Asteraceae, microscopical evaluation, phytochemical, powder microscopy, standardization
Procedia PDF Downloads 4321810 A Study on the Influence of Aswan High Dam Reservoir Loading on Earthquake Activity
Authors: Sayed Abdallah Mohamed Dahy
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Aswan High Dam Reservoir extends for 500 km along the Nile River; it is a vast reservoir in southern Egypt and northern Sudan. It was created as a result of the construction of the Aswan High Dam between 1958 and 1970; about 95% of the main water resources for Egypt are from it. The purpose of this study is to discuss and understand the effect of the fluctuation of the water level in the reservoir on natural and human-induced environmental like earthquakes in the Aswan area, Egypt. In summary, the correlation between the temporal variations of earthquake activity and water level changes in the Aswan reservoir from 1982 to 2014 are investigated and analyzed. This analysis confirms a weak relation between the fluctuation of the water level and earthquake activity in the area around Aswan reservoir. The result suggests that the seismicity in the area becomes active during a period when the water level is decreasing from the maximum to the minimum. Behavior of the water level in this reservoir characterized by a special manner that is the unloading season extends to July or August, and the loading season starts to reach its maximum in October or November every year. Finally, daily rate of change in the water level did not show any direct relation with the size of the earthquakes, hence, it is not possible to be used as a single tool for prediction.Keywords: Aswan high dam reservoir, earthquake activity, environmental, Egypt
Procedia PDF Downloads 3721809 Transient Signal Generator For Fault Indicator Testing
Authors: Mohamed Shaban, Ali Alfallah
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This paper describes an application for testing of a fault indicator but it could be used for other network protection testing. The application is created in the LabVIEW environment and consists of three parts. The first part of the application is determined for transient phenomenon generation and imitates voltage and current transient signal at ground fault originate. The second part allows to set sequences of trend for each current and voltage output signal, up to six trends for each phase. The last part of the application generates harmonic signal with continuously controllable amplitude of current or voltage output signal and phase shift of each signal can be changed there. Further any sub-harmonics and upper harmonics can be added to selected current output signalKeywords: signal generator-fault indicator, harmonic signal generator, voltage output
Procedia PDF Downloads 4861808 Challenges Caused by the Integration of Technology as a Pedagogy in One of the Historically Disadvantaged Higher Education Institutions
Authors: Rachel Gugu Mkhasibe
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Incorporation of technology as a pedagogy has many benefits. For instance, improvement of pedagogy, increased information access, increased cooperation, and collaboration. However, as good as it may be, this integration of technology as a pedagogy has not been widely adopted in most historically Black higher education institutions especially those in developing countries. For example, the socioeconomic background of students in historically black universities, the weak financial support available from these universities, as well as a large population of students struggle to access the recommended modern physical resources such as iPads, laptops, mobile phones, to name a few. This contributes to an increase in the increase of educational inequalities. The qualitative research approach was utilized in this work to gather detailed data about the obstacles created by the integration of technology as a pedagogy. Interviews were conducted to generate data from 20 academics from 10 Leve two students from one of the historically disadvantaged higher education Institutions in South Africa. The findings revealed that although both students and academics had overwhelming support of the integration of technology as a pedagogy in their institution, the environment which they found themselves in compromise the incorporation of technology as a pedagogy. Therefore, this paper recommends that Department of Higher Education and University Management should intervene and budget for technology to be provided in all the institutions of higher education regardless of where the institutions are situated.Keywords: collaboration, integration, pedagogy, technology
Procedia PDF Downloads 751807 Sustainable Water Resource Management and Challenges in Indian Agriculture
Authors: Rajendra Kumar Isaac, Monisha Isaac
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India, having a vast cultivable area and regional climatic variability, encounters water Resource Management Problems at various levels. The agricultural production of India needs to be increased to meet out projected population growth. Sustainable water resource is the only option to ensure food security, especially in northern Indian states, where the ground and surface water resources are fast depleting. Various tools and technologies available for management of scarce water resources have been discussed. It was concluded that multiple use of water, adopting latest water management options, identification of climate adoptable cropping and farming systems, can enhance water productivity and would encounter the fast growing water management and water shortage problems in Indian agriculture.Keywords: water resource management, sustainable, water management technologies, water productivity, agriculture
Procedia PDF Downloads 3931806 Ground Water Sustainable Management in Ethiopia, Africa
Authors: Ebissa Gadissa Kedir
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This paper presents the potential groundwater assessment and sustainable management in the selected study area. It is the most preferred water source in all climatic zones for its convenient availability, drought dependability, excellent quality, and low development cost. The rural areas, which account for more than 85% of the country's population, are encountered a shortage of potable water supply which can be solved by proper groundwater utilization. For the present study area, the groundwater potential is assessed and analysed. Thus, the study area falls in four potential groundwater zones ranging from poor to high. However, the current groundwater management practices in the study area are poor. Despite the pervasive and devastating challenges, immediate and proper responses have not yet been given to the problem. Thus, such frustrating threats and challenges have initiated the researcher to work in the project area.Keywords: GW potential, GW management, GW sustainability, South gonder, Ethiopia
Procedia PDF Downloads 561805 Application of Japanese Origami Ball for Floating Multirotor Aerial Robot
Authors: P. H. Le, J. Molina, S. Hirai
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In this work, we propose the application of Japanese “Origami” art for a floating function of a small aerial vehicle such as a hexarotor. A preliminary experiment was conducted using Origami magic balls mounted under a hexarotor. This magic ball can expand and shrink using an air pump during free flying. Using this interesting and functional concept, it promises to reduce the resistance of wind as well as reduce the energy consumption when the Origami balls are deflated. This approach can be particularly useful in rescue emergency situations. Furthermore, there are many unexpected reasons that may cause the multi-rotor has to land on the surface of water due to problems with the communication between the aircraft and the ground station. In addition, a complementary experiment was designed to prove that the hexarotor can fly maintaining the stability and also, takes off and lands on the surface of water using air balloons.Keywords: helicopter, Japanese origami ball, floating, aerial robots, rescue
Procedia PDF Downloads 3831804 The Concept of Equal Pay: Analyzing the Presence of Inequality in the Hospitality Sector with the Perspective of Employees in Gujarat, India
Authors: Vedi Goenka
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Inequality refers to unequal treatment or perceptions of individuals based on any particular trait. It arises from differences in socially constructed roles. Women are usually characterized as inferior and weak, who are dependent on their male counterparts. Even though it is claimed that both the genders have been given equal rights, inequality has always been prevalent in the Indian society, from personal to the professional front. There are different types of inequality that persist in the corporate world such as age inequality, gender inequality, tenure inequality and so on. Consequently, wage inequality occurs when employees are equally qualified and perform the same task but, one group of employees is paid more than the other. The hospitality sector is one of the emerging sectors in Gujarat which also experiences a lot of organizational dynamics. The proposed paper focuses on the concept of equal pay which states that pay should be based on the kind and quality of work done and not according to any other aspects. An exploratory attempt to understand the existence of inequality in the Hospitality sector on the basis of income is made in this research. The myth that wage discrimination has always favored men over similarly qualified women is analyzed in this research paper. A structured survey of a sample, representative of the employees of the Hospitality sector is being carried out in this study. An attempt to keep the effects of the environmental factors to a minimum level is made.Keywords: equal pay, human resources, hospitality sector, inequality, perspective, wage structure
Procedia PDF Downloads 1791803 A Critical Analysis of the Concept of Unconscionable Abuse under the South African Company Law
Authors: Siphethile Phiri
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Although a company is a legal entity with separate legal personality, the courts are empowered to review and set aside the personality of a company on the ground of ‘an unconscionable abuse’. The process is called piercing of the corporate veil. Of interesting note however, it is controversial as to what the concept of ‘unconscionable abuse’ entails. The purpose of this study is to explore this concept in an attempt to understand its proper meaning and how it bears on the powers of the company director to take decision on behalf of the company as a juristic entity. Given the confounding provision, an attempt is made to identify the circumstances in which the courts may pierce the corporate veil and also to investigate the extent to which the courts can do so. The results of this study show that the term unconscionable abuse is a legislative innovation to justify the court’s interference with the separate legal personality functions of a company.Keywords: company law, unconscionable abuse, director, companies act
Procedia PDF Downloads 2871802 Identifying the Structural Components of Old Buildings from Floor Plans
Authors: Shi-Yu Xu
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The top three risk factors that have contributed to building collapses during past earthquake events in Taiwan are: "irregular floor plans or elevations," "insufficient columns in single-bay buildings," and the "weak-story problem." Fortunately, these unsound structural characteristics can be directly identified from the floor plans. However, due to the vast number of old buildings, conducting manual inspections to identify these compromised structural features in all existing structures would be time-consuming and prone to human errors. This study aims to develop an algorithm that utilizes artificial intelligence techniques to automatically pinpoint the structural components within a building's floor plans. The obtained spatial information will be utilized to construct a digital structural model of the building. This information, particularly regarding the distribution of columns in the floor plan, can then be used to conduct preliminary seismic assessments of the building. The study employs various image processing and pattern recognition techniques to enhance detection efficiency and accuracy. The study enables a large-scale evaluation of structural vulnerability for numerous old buildings, providing ample time to arrange for structural retrofitting in those buildings that are at risk of significant damage or collapse during earthquakes.Keywords: structural vulnerability detection, object recognition, seismic capacity assessment, old buildings, artificial intelligence
Procedia PDF Downloads 791801 Required SNR for PPM in Downlink Gamma-Gamma Turbulence Channel
Authors: Selami Şahin
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In this paper, in order to achieve sufficient bit error rate (BER) according to zenith angle of the satellite to ground station, SNR requirement is investigated utilizing pulse position modulation (PPM). To realize explicit results, all parameters such as link distance, Rytov variance, scintillation index, wavelength, aperture diameter of the receiver, Fried's parameter and zenith angle have been taken into account. Results indicate that after some parameters are determined since the constraints of the system, to achieve desired BER, required SNR values are in wide range while zenith angle changes from small to large values. Therefore, in order not to utilize high link margin, either SNR should adjust according to zenith angle or link should establish with predetermined intervals of the zenith angle.Keywords: Free-space optical communication, optical downlink channel, atmospheric turbulence, wireless optical communication
Procedia PDF Downloads 3901800 Concrete-Wall-Climbing Testing Robot
Authors: S. Tokuomi, K. Mori, Y. Tsuruzono
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A concrete-wall-climbing testing robot, has been developed. This robot adheres and climbs concrete walls using two sets of suction cups, as well as being able to rotate by the use of the alternating motion of the suction cups. The maximum climbing speed is about 60 cm/min. Each suction cup has a pressure sensor, which monitors the adhesion of each suction cup. The impact acoustic method is used in testing concrete walls. This robot has an impact acoustic device and four microphones for the acquisition of the impact sound. The effectiveness of the impact acoustic system was tested by applying it to an inspection of specimens with artificial circular void defects. A circular void defect with a diameter of 200 mm at a depth of 50 mm was able to be detected. The weight and the dimensions of the robot are about 17 kg and 1.0 m by 1.3 m, respectively. The upper limit of testing is about 10 m above the ground due to the length of the power cable.Keywords: concrete wall, nondestructive testing, climbing robot, impact acoustic method
Procedia PDF Downloads 6521799 Half Metallic Antiferromagnetic of Doped TiO2 Rutile with Doubles Impurities (Os, Mo) from Ab Initio Calculations
Authors: M. Fakhim Lamrani, M. Ouchri, M. Belaiche, El Kenz, M. Loulidi, A. Benyoussef
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Electronic and magnetic calculations based on density functional theory within the generalized gradient approximation for II-VI compound semiconductor TiO2 doped with single impurity Os and Mo; these compounds are a half metallic ferromagnet in their ground state with a total magnetic moment of 2 μB for both systems. Then, TiO2 doped with double impurities Os and Mo have been performed. As result, Ti1-2xOsxMoxO2 with x=0.065 is half-metallic antiferromagnets with 100% spin polarization of the conduction electrons crossing the Fermi level, without showing a net magnetization. Moreover, Ti14OsMoO32 compound is stable energetically than Ti1-xMoxO2 and Ti1-xOsxO2. The antiferromagnetic interaction in Ti1-2xOsxMoxO2 system is attributed to the double exchange mechanism, and the latter could also be the origin of their half metallic.Keywords: diluted magnetic semiconductor, half-metallic antiferromagnetic, augmented spherical wave method
Procedia PDF Downloads 4151798 Estimation of Foliar Nitrogen in Selected Vegetation Communities of Uttrakhand Himalayas Using Hyperspectral Satellite Remote Sensing
Authors: Yogita Mishra, Arijit Roy, Dhruval Bhavsar
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The study estimates the nitrogen concentration in selected vegetation community’s i.e. chir pine (pinusroxburghii) by using hyperspectral satellite data and also identified the appropriate spectral bands and nitrogen indices. The Short Wave InfraRed reflectance spectrum at 1790 nm and 1680 nm shows the maximum possible absorption by nitrogen in selected species. Among the nitrogen indices, log normalized nitrogen index performed positively and negatively too. The strong positive correlation is taken out from 1510 nm and 760 nm for the pinusroxburghii for leaf nitrogen concentration and leaf nitrogen mass while using NDNI. The regression value of R² developed by using linear equation achieved maximum at 0.7525 for the analysis of satellite image data and R² is maximum at 0.547 for ground truth data for pinusroxburghii respectively.Keywords: hyperspectral, NDNI, nitrogen concentration, regression value
Procedia PDF Downloads 2901797 Students' Perceptions and Gender Relationships towards the Mobile Learning in Polytechnic Mukah Sarawak (Malaysia)
Authors: Habsah Mohamad Sabli, Mohammad Fardillah Wahi
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The main aim of this research study is to better understand and measure students' perceptions towards the effectiveness of mobile learning. This paper reports on the results of a survey of three hundred nineteen students at Polytechnic Mukah Sarawak (PMU) about their perception to the use of mobile technology in education. An analysis of the quantitative survey findings is presented focusing on the ramification for mobile-learning (m-learning) practices in higher learning and teaching environments. In this paper we present our research findings about the level of perception and gender correlations with perceived ease of use and perceived usefulness using M-Learning in learning activities among students in Polytechnic Mukah (PMU). Based on gender respondent, were 150 female (47.0%) and 169 male (53.0%). The survey findings further revealed that perception of students are in moderately high and agree for using m-learning. The perceived ease of use and perceived usefulness is significant with weak correlations between students to adapt m-learning for active learning activities. The outcome of this research can benefit the decision makers of higher institution in Mukah Sarawak regard to way to enhance m-learning and promote effective teaching and learning activities as well as strengthening the quality of learning delivery.Keywords: M-learning, student attitudes, student perception, mobile technology
Procedia PDF Downloads 4961796 Investigating the Influence of Roof Fairing on Aerodynamic Drag of a Bluff Body
Authors: Kushal Kumar Chode
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Increase in demand for fuel saving and demand for faster vehicles with decent fuel economy, researchers around the world started investigating in various passive flow control devices to improve the fuel efficiency of vehicles. In this paper, A roof fairing was investigated for reducing the aerodynamic drag of a bluff body. The bluff body considered for this work is Ahmed model with a rake angle of 25deg was and subjected to flow with a velocity of 40m/s having Reynolds number of 2.68million was analysed using a commercial Computational Fluid Dynamic (CFD) code Star CCM+. It was evident that pressure drag is the main source of drag on an Ahmed body from the initial study. Adding a roof fairing has delayed the flow separation and resulted in delaying wake formation, thus improving the pressure in near weak and reducing the wake region. Adding a roof fairing of height and length equal to 1/7H and 1/3L respectively has shown a drag reduction by 9%. However, an optimised fairing, which was obtained by changing height, length and width by 5% increase, recorded a drag reduction close 12%.Keywords: Ahmed model, aerodynamic drag, passive flow control, roof fairing, wake formation
Procedia PDF Downloads 4291795 Spectroscopic Study of a Eu-Complex Containing Hybrid Material
Authors: Y. A. R. Oliveira, M. A. Couto dos Santos, N. B. C. Júnior, S. J. L. Ribeiro, L. D. Carlos
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The Eu(TTA)3(H2O)2 complex (TTA = thenoyltrifluoroacetone) pure (EuTTA) and incorporated in an organicinorganic hybrid material (EuTTA-hyb) are revisited, this time from the crystal field parameters (CFP) and Judd-Ofelt intensity parameters (Ωλ) point of view. A detailed analysis of the emission spectra revealed that the EuTTA phase still remains in the hybrid phase. Sparkle Model calculations of the EuTTA ground state geometry have been performed and satisfactorily compared to the X-ray structure. The observed weaker crystal field strength of the phase generated by the incorporation is promptly interpreted through the existing EXAFS results of the EuTTA-hyb structure. Satisfactory predictions of the CFP, of the 7F1 level splitting and of the Ωλ in all cases were obtained by using the charge factors and polarizabilities as degrees of freedom of non-parametric models.Keywords: crystal field parameters, europium complexes, Judd-Ofelt intensity parameters
Procedia PDF Downloads 4011794 Ground Water Monitoring Using High-Resolution Fiber Optics Cable Sensors (FOCS)
Authors: Sayed Isahaq Hossain, K. T. Chang, Moustapha Ndour
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Inference of the phreatic line through earth dams is of paramount importance because it could be directly associated with piping phenomena which may lead to the dam failure. Normally in the field, the instrumentations such as ‘diver’ and ‘standpipe’ are to be used to identify the seepage conditions which only provide point data with a fair amount of interpolation or assumption. Here in this paper, we employed high-resolution fiber optic cable sensors (FOCS) based on Raman Scattering in order to obtain a very accurate phreatic line and seepage profile. Unlike the above-mention devices which pinpoint the water level location, this kind of Distributed Fiber Optics Sensing gives us more reliable information due to its inherent characteristics of continuous measurement.Keywords: standpipe, diver, FOCS, monitoring, Raman scattering
Procedia PDF Downloads 3461793 Seismic Fragility for Sliding Failure of Weir Structure Considering the Process of Concrete Aging
Authors: HoYoung Son, Ki Young Kim, Woo Young Jung
Abstract:
This study investigated the change of weir structure performances when durability of concrete, which is the main material of weir structure, decreased due to their aging by mean of seismic fragility analysis. In the analysis, it was assumed that the elastic modulus of concrete was reduced by 10% in order to account for their aged deterioration. Additionally, the analysis of seismic fragility was based on Monte Carlo Simulation method combined with a 2D nonlinear finite element in ABAQUS platform with the consideration of deterioration of concrete. Finally, the comparison of seismic fragility of model pre- and post-deterioration was made to study the performance of weir. Results show that the probability of failure in moderate damage for deteriorated model was found to be larger than pre-deterioration model when peak ground acceleration (PGA) passed 0.4 g.Keywords: weir, FEM, concrete, fragility, aging
Procedia PDF Downloads 423