Search results for: sloping ground

Authors: Mankour Mohamed, Miloudi Mohamed

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A thorough and accurate simulation is necessary for the study of a High Voltage Direct Current (HVDC) link system during various types of disturbances, including internal faults on both converters, either on the rectifier or on the inverter, as well as external faults, such as AC or DC faults on both converter sides inside the DC link party. In this study, we examine how an HVDC inverter responds to three different types of failures, including faults at the inverter valve, system control faults, and single-phase-to-ground AC faults at the sending end of the inverter side. As this phenomenon represents the most frequent problem that may affect inverter valves, particularly those based on thyristor valves (LCC (line-Commutated converter)), it is more precise to explore which circumstance generates and raises the commutation failure on inverter valves. Because of the techniques used to accelerate the simulation, digital real-time simulators are now the most potent tools that provide simulation results. The real-time-lab RT-LAB platform HYPERSIM OP-5600 is used to implement the Simulation in the Loop (SIL) technique, which is used to validate the results. It is demonstrated how to recover from both the internal faults and the AC problem. The simulation findings show how crucial a role the control system plays in fault recovery.

Keywords: hypersim simulator, HVDC systems, mono-polar link, AC faults, misfiring faults

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Authors: Femy M. Makkar, S. Chandrakaran, N. Sankar

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The concept of reinforced earth has been used in the field of geotechnical engineering since 1960s, for many applications such as, construction of road and rail embankments, pavements, retaining walls, shallow foundations, soft ground improvement and so on. Conventionally, planar geosynthetic materials such as geotextiles and geogrids were used as the reinforcing elements. Recently, the use of three dimensional reinforcements becomes one of the emerging trends in this field. So, in the present investigation, three dimensional geogrid is proposed as a reinforcing material. Laboratory scaled plate load tests are conducted on a model square footing resting on 3D geogrid reinforced sand bed. The performance of 3D geogrids in triangular and square pattern was compared with conventional geogrids and the improvement in bearing capacity and reduction in settlement and heave are evaluated. When single layer of reinforcement was placed at an optimum depth of 0.25B from the bottom of the footing, the bearing capacity of conventional geogrid reinforced soil improved by 1.85 times compared to unreinforced soil, where as 3D geogrid reinforced soil with triangular pattern and square pattern shows 2.69 and 3.05 times improvement respectively compared to unreinforced soil. Also, 3D geogrids performs better than conventional geogrids in reducing the settlement and heave of sand bed around the model footing.

Keywords: 3D reinforcing elements, bearing capacity, heavy, settlement

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Authors: Hamd Ahmed

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During the Persian Gulf War in 1991s, The confederation forces were surprised when they were being shot at by friendly forces in Iraqi desert. As obvious was the fact that they were mislead due to the lack of proper guidance and technology resulting in unnecessary loss of life and bloodshed. This unforeseen incident along with many others led the US department of defense to open the doors of GPS. In the very beginning, this technology was for military use, but now it is being widely used and increasingly popular among the public due to its high accuracy and immeasurable significance. The GPS system simply consists of three segments, the space segment (the satellite), the control segment (ground control) and the user segment (receiver). This project work is about designing a 1.57GHZ mixer for triple conversion GPS receiver .The GPS Front-End receiver based on super heterodyne receiver which improves selectivity and image frequency. However the main principle of the super heterodyne receiver depends on the mixer. Many different types of mixers (single balanced mixer, Single Ended mixer, Double balanced mixer) can be used with GPS receiver, it depends on the required specifications. This research project will provide an overview of the GPS system and details about the basic architecture of the GPS receiver. The basic emphasis of this report in on investigating general concept of the mixer circuit some terms related to the mixer along with their definitions and present the types of mixer, then gives some advantages of using singly balanced mixer and its application. The focus of this report is on how to design mixer for GPS receiver and discussing the simulation results.

Keywords: GPS , RF filter, heterodyne, mixer

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Authors: Ayesha Hasan

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This study offers unique perspectives and analyses of peace and conflict journalism through interpretative repertoire, media frames, and critical discourse analyses. Two major English publications in Pakistan, representing both long and short-form journalism, are investigated to uncover how the Afghan refugee repatriation from Pakistan in 2016-17 has been framed in Pakistani English media. Peace journalism focuses on concepts such as peace initiatives and peace building, finding common ground, and preventing further conflict. This study applies Jake Lynch’s Coding Criteria to guide the critical discourse analysis and Lee and Maslog’s Peace Journalism Quotient to examine the extent of peace journalism in each text. This study finds that peace journalism is missing in Pakistani English press, but represented, to an extent, in long-form print and online coverage. Two new alternative frames are also proposed. This study gives an in-depth understanding of if and how journalists in Pakistan are covering conflicts and framing stories that can be identified as peace journalism. This study represents significant contributions to the remarkably limited scholarship on peace and conflict journalism in Pakistan and extends Shabbir Hussain’s work on critical pragmatic perspectives on peace journalism in Pakistan.

Keywords: Afghan refugee repatriation, Critical discourse analysis, Media framing , Peace and conflict journalism

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Authors: Emmanuel Sachikumba, Micheal Msoni, Westone Mafuleka

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Zambia has a good climate with favourable rainfall pattern; this provides sufficient recharge for the surface and groundwater resources. In spite of the sufficient surface and ground water resources, accessibility to water at household levels is problematic both in quality and quantity. The study examined water accessibility as well as water quality at the household level. The research looked at the sources of water for the households and considered the complications of accessibility to water and the available opportunities therein. The investigation involved fifty households and the data was collected by the use of questionnaires (to assess accessibility) and laboratory tests (for ascertaining water quality). In addition to this, government departments such as the health, agriculture, forestry and education as well as the municipal council were interviewed on the topic under study. The study was descriptive in nature where clustered sampling procedures using simple random methods were utilised to select the households which were to participate in the study. The key findings were that; accessibility to water household levels is still a challenge in the settlement as most of the point sources (shallow wells, the stream and the river) were found to be contaminated. In addition to this, it was found that there was no direct relationship between the economic performance of a household and the accessibility to water. The study also observed that there were opportunities for the people in the settlement as they were increasingly getting into the education system, and adult literacy was being encouraged in the settlement. Furthermore, the settlement has groundwater resources which indicate that there can be sufficient water provision for the settlers.

Keywords: accessibility, household, water, settlement

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Authors: Xuan Ban, Li Pengsheng, Pengcheng Li, Ming Zhang, ChuYang Zheng, Qingjing Wu, Hao Du

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Assessing habitat quality is essential for habitat restoration and conservation, especially for critically endangered species such as the Chinese sturgeon, a 1.4-million-year-old anadromous fish known as a ‘living fossil’. This species faces significant threats to its habitat in the Yangtze River, where it has ceased to reproduce naturally and the wild population is close to extinction. Our study provides a nuanced understanding of habitat degradation by integrating ecohydraulics and landscape ecology, focusing on the mechanisms behind the degradation of the sturgeon's spawning grounds. Using the Geographic Detector Model and physical habitat simulation, we analyze how ecohydraulic parameters, in particular those related to turbulent kinetic energy, affect sturgeon spawning. We also assess habitat fragmentation and patch size, which are key determinants of habitat quality and connectivity. Our results link the decline in habitat quality to the loss of spawning habitat due to dam construction and changes in water flow. To address this, we propose interventions such as flow optimization during the spawning season and topography rehabilitation to improve spawning conditions and support sturgeon recovery. This work contributes to the development of a comprehensive approach to assessing habitat quality and provides a scientific basis for conservation strategies for threatened fish species.

Keywords: Chinese sturgeon, spawning ground, eco-hydraulics, landscape index, habitat suitability, habitat quality

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Authors: V. Revathi, J. Thaarrini, M. Venkob Rao

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This paper presents a study on use of alkali activated bottom ash (BA) and ground granulated blast furnace slag (GGBS) blend in paver blocks. A preliminary effort on alkali-activated bottom ash, blast furnace slag based geopolymer (BA-GGBS-GP) mortar with river sand was carried out to identify the suitable mix for paver block. Several mixes were proposed based on the combination of BA-GGBS. The percentage ratio of BA:GGBS was selected as 100:0, 75:25, 50:50, 25:75 and 0:100 for the source material. Sodium based alkaline activators were used for activation. The molarity of NaOH was considered as 8M. The molar ratio of SiO2 to Na2O was varied from 1 to 4. Two curing mode such as ambient and steam curing 60°C for 24 hours were selected. The properties of paver block such as compressive strength split tensile strength, flexural strength and water absorption were evaluated as per IS15658:2006. Based on the preliminary study on BA-GGBS-GP mortar, the combinations of 25% BA with 75% GGBS mix for M30 and 75% BA with 25% GGBS mix for M35 grade were identified for paver block. Test results shows that the combination of BA-GGBS geopolymer paver blocks attained remarkable compressive strength under steam curing as well as in ambient mode at 3 days. It is noteworthy to know BA-GGBS-GP has promising future in the construction industry.

Keywords: bottom ash, GGBS, alkali activation, paver block

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Authors: Krishna Raj Regmi

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A “Climate change adaptation and disaster risk management for sustainable agriculture” project was implemented in Nepal, a Himalayan country during 2008 to 2013 sponsored jointly by Food and Agriculture Organization (FAO) and United Nations Development Programme (UNDP), Nepal. The paper is based on the results and findings of this joint pilot project. The climate change events such as increased intensity of erratic rains in short spells, trend of prolonged drought, gradual rise in temperature in the higher elevations and occurrence of cold and hot waves in Terai (lower plains) has led to flash floods, massive erosion in the hills particularly in Churia range and drying of water sources. These recurring natural and climate-induced disasters are causing heavy damages through sedimentation and inundation of agricultural lands, crops, livestock, infrastructures and rural settlements in the downstream plains and thus reducing agriculture productivity and food security in the country. About 65% of the cultivated land in Nepal is rainfed with drought-prone characteristics and stabilization of agricultural production and productivity in these tracts will be possible through adoption of rainfed and drought-tolerant technologies as well as efficient soil-water management by the local communities. The adaptation and mitigation technologies and options identified by the project for soil erosion, flash floods and landslide control are on-farm watershed management, sloping land agriculture technologies (SALT), agro-forestry practices, agri-silvi-pastoral management, hedge-row contour planting, bio-engineering along slopes and river banks, plantation of multi-purpose trees and management of degraded waste land including sandy river-bed flood plains. The stress tolerant technologies with respect to drought, floods and temperature stress for efficient utilization of nutrient, soil, water and other resources for increased productivity are adoption of stress tolerant crop varieties and breeds of animals, indigenous proven technologies, mixed and inter-cropping systems, system of rice/wheat intensification (SRI), direct rice seeding, double transplanting of rice, off-season vegetable production and regular management of nurseries, orchards and animal sheds. The alternate energy use options and resource conservation practices for use by local communities are installation of bio-gas plants and clean stoves (Chulla range) for mitigation of green house gas (GHG) emissions, use of organic manures and bio-pesticides, jatropha cultivation, green manuring in rice fields and minimum/zero tillage practices for marshy lands. The efficient water management practices for increasing productivity of crops and livestock are use of micro-irrigation practices, construction of water conservation and water harvesting ponds, use of overhead water tanks and Thai jars for rain water harvesting and rehabilitation of on-farm irrigation systems. Initiation of some works on community-based early warning system, strengthening of met stations and disaster database management has made genuine efforts in providing disaster-tailored early warning, meteorological and insurance services to the local communities. Contingent planning is recommended to develop coping strategies and capacities of local communities to adopt necessary changes in the cropping patterns and practices in relation to adverse climatic and disaster risk conditions. At the end, adoption of awareness raising and capacity development activities (technical and institutional) and networking on climate-induced disaster and risks through training, visits and knowledge sharing workshops, dissemination of technical know-how and technologies, conduct of farmers' field schools, development of extension materials and their displays are being promoted. However, there is still need of strong coordination and linkage between agriculture, environment, forestry, meteorology, irrigation, climate-induced pro-active disaster preparedness and research at the ministry, department and district level for up-scaling, implementation and institutionalization of climate change and disaster risk management activities and adaptation mitigation options in agriculture for sustainable livelihoods of the communities.

Keywords: climate change adaptation, disaster risk management, soil-water management practices, sustainable agriculture

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Authors: Neslinur Hizli, Berrak Kirbaş Akyürek

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Beşiktaş, one of the historical coastal district of İstanbul, is on the very edge of the radical transformation because of an approaching ‘Beşiktaş Public Square Project’. At this juncture, due its location, presence on the coast, population density and distance to the other centers of the city, the decisions to be taken are critical to whole Istanbul that will be majorly affected from this transformation. As the new project aims to pedestrianize the area by placing the vehicular traffic under the ground, Beşiktaş and its square will change from top to bottom. Among those considerations, through the advantages and disadvantages the perception of the existing conditions of the Beşiktaş play significant role. The motive of this paper is the lack of determination and clarity on the cognition of the Square. After brief analysis on the historical transformation of the area, prominent studies on the criteria of public square are revised. Through cognitive mapping methodology, characteristics of the Square and the public space in general find a place to discuss from individual views. This study aims to discuss and review Beşiktaş Public Square from perspective, mind and behavior of the users. Cognitive map study with thirty subjects (30) is evaluated and categorized upon the five elements that Kevin Lynch defined as the images of the city. The results obtained digitized and represented with tables and graphs. Findings of the research underline the crucial issues on the approaching change in Beşiktaş. Thus, this study may help to develop comprehensive ideas and new suggestions on the Square.

Keywords: Beşiktaş public square, cognitive map, perception, public space

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Authors: S. Lekhavat, T. Kajsongkram, S. Sang-han

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Dried ginger was extracted and investigated the effect of ethanol concentration and enzyme pre-treatment on its bioactive compounds in solvent extraction process. Sliced fresh gingers were dried by oven dryer at 70 °C for 24 hours and ground to powder using grinder which their size were controlled by passing through a 20-mesh sieve. In enzyme pre-treatment process, ginger powder was sprayed with 1 % (w/w) cellulase and then was incubated at 45 °C for 2 hours following by extraction process using ethanol at concentration of 0, 20, 40, 60 and 80 % (v/v), respectively. The ratio of ginger powder and ethanol are 1:9 and extracting conditions were controlled at 80 °C for 2 hours. Bioactive compounds extracted from ginger, either enzyme-treated or non enzyme-treated samples, such as total phenolic content (TPC), 6-Gingerol (6 G), 6-Shogaols (6 S) and antioxidant activity (IC50 using DPPH assay), were examined. Regardless of enzyme treatment, the results showed that 60 % ethanol provided the highest TPC (20.36 GAE mg /g. dried ginger), 6G (0.77%), 6S (0.036 %) and the lowest IC50 (625 μg/ml) compared to other ratios of ethanol. Considering the effect of enzyme on bioactive compounds and antioxidant activity, it was found that enzyme-treated sample has more 6G (0.17-0.77 %) and 6S (0.020-0.036 %) than non enzyme-treated samples (0.13-0.77 % 6G, 0.015-0.036 % 6S). However, the results showed that non enzyme-treated extracts provided higher TPC (6.76-20.36 GAE mg /g. dried ginger) and Lowest IC50 (625-1494 μg/ml ) than enzyme-treated extracts (TPC 5.36-17.50 GAE mg /g. dried ginger, IC50 793-2146 μg/ml).

Keywords: antioxidant activity, enzyme, extraction, ginger

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Authors: Zehai Yu, Hui Zhu, Linglong Lin, Huawei Liang, Biao Yu, Weixin Huang

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With the development of intelligent vehicle systems, a high-precision road map is increasingly needed in many aspects. The automatic lane lines extraction and modeling are the most essential steps for the generation of a precise lane-level road map. In this paper, an automatic lane-level road map generation system is proposed. To extract the road markings on the ground, the multi-region Otsu thresholding method is applied, which calculates the intensity value of laser data that maximizes the variance between background and road markings. The extracted road marking points are then projected to the raster image and clustered using a two-stage clustering algorithm. Lane lines are subsequently recognized from these clusters by the shape features of their minimum bounding rectangle. To ensure the storage efficiency of the map, the lane lines are approximated to cubic polynomial curves using a Bayesian estimation approach. The proposed lane-level road map generation system has been tested on urban and expressway conditions in Hefei, China. The experimental results on the datasets show that our method can achieve excellent extraction and clustering effect, and the fitted lines can reach a high position accuracy with an error of less than 10 cm.

Keywords: curve fitting, lane-level road map, line recognition, multi-thresholding, two-stage clustering

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Authors: M. A. Meslem

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For precise geoid determination, we use a reference field to subtract long and medium wavelength of the gravity field from observations data when we use the remove-compute-restore technique. Therefore, a comparison study between considered models should be made in order to select the optimal reference gravity field to be used. In this context, two recent global geopotential models have been selected to perform this comparison study over Northern Algeria. The Earth Gravitational Model (EGM2008) and the Global Gravity Model (GECO) conceived with a combination of the first model with anomalous potential derived from a GOCE satellite-only global model. Free air gravity anomalies in the area under study have been used to compute residual data using both gravity field models and a Digital Terrain Model (DTM) to subtract the residual terrain effect from the gravity observations. Residual data were used to generate local empirical covariance functions and their fitting to the closed form in order to compare their statistical behaviors according to both cases. Finally, height anomalies were computed from both geopotential models and compared to a set of GPS levelled points on benchmarks using least squares adjustment. The result described in details in this paper regarding these two models has pointed out a slight advantage of GECO global model globally through error degree variances comparison and ground-truth evaluation.

Keywords: quasigeoid, gravity aomalies, covariance, GGM

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Authors: Wilmer Esteban Vallejo Narváez, Serguei Fomine

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The theoretical investigation of Si-doped graphene nanoflakes (NFs) was conducted to understand their catalytic impact on CO₂ reduction using molecular hydrogen at the Density Functional Theory (DFT) level. The introduction of silicon by substituting carbon induces defects in the NF structure, resulting in a polyradical ground state. This silicon defect significantly boosts reactivity towards substrates, making Si-doped graphene NFs more catalytically active in CO₂ reduction to formic acid compared to silicene. Notably, Si-doped graphene demonstrates a preference for formic acid over carbon monoxide, mirroring the behavior of silicene. Furthermore, investigations into formic acid-to-formaldehyde and formaldehyde-to-methanol conversions reveal instances where Si-doped graphene outperforms silicene in terms of efficacy. In the final reduction step, the methanol-to-methane reaction unfolds in four stages, with the rate-determining step involving hydrogen transfer from silicon to methyl. Notably, the activation energy for this step is lower in Si-doped graphene compared to silicene. Consequently, Si-doped graphene NFs emerge as superior catalysts with lower activation energies overall. Remarkably, throughout these catalytic processes, Si-doped graphene maintains environmental stability, further highlighting its enhanced catalytic activity without compromising graphene's inherent stability.

Keywords: silicon-doped graphene, CO₂ reduction, DFT, catalysis

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Authors: Philippa Anne French

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This paper presents a case study of 3000acres, a for-purpose organisation established in 2013 to improve the health of Melbournians by enabling them to grow more of their own food. Over the past four years, the organisation has encountered a number of barriers, both obvious and less obvious, which discourage communities from beginning their own food-growing projects. These include soil contamination, planning policies, public perception and access to land. 3000acres has been working to remove these barriers if possible, or otherwise to find ways around them. Strategies have included the use of removable planter boxes on temporarily vacant land, separating the site soil from above-ground garden beds, writing planning exemptions, developing relationships with land management authorities and recording both the quantitative and qualitative products of food gardens in Melbourne. While creating change in policy and legal requirements will be a gradual process, discernable progress has been made in the attitudes of land management authorities and the establishment of new food gardens is becoming easier. Over the past four years, 3000acres has supported the establishment of 14 food gardens in and around Melbourne, including public community gardens, fenced community gardens and urban farms supplying food to a food relief organisation.

Keywords: case study, community gardens, land access, land contamination, urban agriculture

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Authors: Ellen Nhedzi Gozo

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Unavailability of adequate hydro-meteorological data has always limited the analysis and understanding of hydrological behaviour of several dam catchments including Mazowe Dam in Zimbabwe. The problem of insufficient data for Mazowe Dam catchment analysis was solved by extracting catchment characteristics and aerial hydro-meteorological data from ASTER, LANDSAT, Shuttle Radar Topographic Mission SRTM remote sensing (RS) images using ILWIS, ArcGIS and ERDAS Imagine geographic information systems (GIS) software. Available observed hydrological as well as meteorological data complemented the use of the remotely sensed information. Ground truth land cover was mapped using a Garmin Etrex global positioning system (GPS) system. This information was then used to validate land cover classification detail that was obtained from remote sensing images. A bathymetry survey was conducted using a SONAR system connected to GPS. Hydrological modelling using the HBV model was then performed to simulate the hydrological process of the catchment in an effort to verify the reliability of the derived parameters. The model output shows a high Nash-Sutcliffe Coefficient that is close to 1 indicating that the parameters derived from remote sensing and GIS can be applied with confidence in the analysis of Mazowe Dam catchment.

Keywords: geographic information systems, hydrological modelling, remote sensing, water resources management

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Authors: Galih Permana, Yuskar Lase

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In recent years, damping device has been experimentally studied to replace diagonally reinforced coupling beams, to mitigate rebar congestion problem. This study focuses on evaluating the effectiveness of various damping devices in a high-rise building. The type of damping devices evaluated is Viscoelastic Damper (VCD) and Rotational Friction Damper (RFD), with study case of a 15-story reinforced concrete apartment building with a dual system (column-beam and shear walls). The analysis used is a nonlinear time history analysis with 11 pairs of ground motions matched to the Indonesian response spectrum based on ASCE 41-17 and ASCE 7-16. In this analysis, each damper will be varied with a different position, namely the first model, the damper will be installed on the entire floor and in the second model, the damper will be installed on the 5th floor to the 9th floor, which is the floor with the largest drift. The results show that the model using both dampers increases the level of structural performance both globally and locally in the building, which will reduce the level of damage to the structural elements. But between the two dampers, the coupling beam that uses RFD is more effective than using VCD in improving building performance. The damper on the coupling beam has a good role in dissipating earthquakes and also in terms of ease of installation.

Keywords: building, coupling beam, damper, nonlinear time history analysis

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Authors: Nazakat Ismailzada, Carol Jones

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Tomato drilling moth Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae) is the main pest of tomato plants in many countries. The larvae of tomato leaves, the stems inside, in the end buds, they opened the gallery in green and ripe fruit. In this way the harmful products can be fed with all parts of the tomato plant can cause damage to 80-100%. Pest harms all above ground parts of the tomato plant. After the seedlings are planted in areas and during blossoming holder traps with tomato moth’s rubber capsule inside should be placed in the area by using five-tomato moth’s feremon per ha. Then there should be carried out observations in the fields in every three days regularly. During the researches, it was showed that in field condition Carogen 20 SC besides high-level biological efficiency also has low ecological load for environment, and should be used against tomato moth in farms. Therefore it was showed that in field condition Carogen 20 SC besides high-level biological efficiency also has low ecological load for environment, and should be used against tomato moth in farms with insecticide expenditure norm 320 qr\ha. In farms should be used plant rotation, plant fields should be plowed on the 25-30 sm depth, before sowing seeds should be proceeded by insecticides. As element of integrated plant protection activities, should be used pheromones trap. In tomato plant fields as an insecticide should be used AGROSAN 240 SC and Carogen 20 SP.

Keywords: lepidoptera, Tuta absoluta, chemical control, integrated pest management

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Authors: Steven D. P. Moore

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An electrical discharge in the air induces an electromagnetic (EM) wave capable of wireless transfer, reception, and conversion back into electrical discharge at a distant location. Following Norton’s ground wave principles, EM wave radiation (EMR) runs parallel to the Earth’s surface. Energy in an EMR wave can move through the air and be focused to create a spark at a distant location, focused by a receiver to generate a local electrical discharge. This local discharge can be amplified and stored but also has the propensity to initiate another EMR wave. In addition to typical EM waves, lightning is also associated with atmospheric events, trans-ionospheric pulse pairs, the most powerful natural EMR signal on the planet. With each lightning strike, regardless of global position, it generates naturally occurring pulse-pairs that are emitted towards space within a narrow cone. An EMR wave can self-propagate, travel at the speed of light, and, if polarized, contain vector properties. If this reflective pulse could be directed by design through structures that have increased probabilities for lighting strikes, it could theoretically travel near the surface of the Earth at light speed towards a selected receiver for local transformation into electrical energy. Through research, there are several influencing parameters that could be modified to model, test, and increase the potential for adopting this technology towards the goal of developing a global grid that utilizes natural sources of energy.

Keywords: electricity, sparkgap, wireless, electromagnetic

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Authors: Mark K. Johnson

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Arvo Pärt has composed over 80 text-based compositions based on nine different languages. But prior to 2015, it was not publicly known what texts the composer used in composing a number of his non-vocal works, nor the language of those texts. Because of this lack of information, few if any musical scholars have illustrated in any detail how textual structure applies to any of Pärt’s instrumental compositions. However, in early 2015, the Arvo Pärt Centre in Estonia published In Principio, a compendium of the texts Pärt has used to derive many of the parameters of his text-based compositions. This paper provides the first detailed analysis of the relationship between structural aspects of the Church Slavonic Eastern Orthodox text of Psalm 112 and the musical parameters that Pärt used when composing the string orchestral work Psalom. It demonstrates that Pärt’s text-based compositions are carefully crafted works, and that evidence of the presence of the ‘invisible’ hand of the composer can be found within every aspect of the underpinning structures, at the more elaborate middle ground level, and even within surface aspects of these works. Based on the analysis of Psalom, it is evident that the text Pärt selected for Psalom informed many of his decisions regarding the musical structures, parameters and processes that he deployed in composing this non-vocal text-based work. Many of these composerly decisions in relation to these various aspects cannot be fathomed without access to, and an understanding of, the text associated with the work.

Keywords: Arvo Pärt, minimalism, psalom, text-based process music

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Authors: Azadeh Jafari, Mohammad Taghi Karimi, Azadeh Nadi

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Background: Scoliosis is the lateral curvature of the spine which may influence the abilities of the subjects during standing and walking. Most of the scoliotic subjects use orthosis to reduce the curve and to decrease the risk of curve progression. There was lack of information regarding the effects of orthosis on kinematic and joint contact force. Therefore, this research was done to highlight the effects of orthosis on the aforementioned parameters. Method: 5 scoliotic subjects were recruited in this study, with single curve less than 40 (females with age 13.2 ± 1.7). They were asked to walk with and without orthosis. The kinematic of the joints, force applied on the legs, moments transmitted through the joints and joint contact forces were evaluated in this study. Moreover, the lengths of muscles were determined by use of computer muscle control approach in OpenSim. Results: There was a significant difference between the second peak of vertical ground reaction force while walking with and without orthosis (p-value < 0.05). There was no difference between spatiotemporal gait parameters while walking with and without orthosis (P-value > 0.05). The mean values of joint contact forces (vertical component) increased by the use of orthosis, but the difference was not significant (p-value > 0.05). Conclusion: Although the kinematic of most of the body joints was not influenced by the use of orthosis, the joint contact force may be increased by orthosis. The increase in joint contact force may be due to the performance of orthosis which restricts the motions of pelvic and increases compensatory mechanism used by the subjects to decrease the side effects of the orthosis.

Keywords: scoliosis, joint contact force, kinetic, kinematic

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Authors: Ankur P. Sati, Manju Mohan

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The hazardous combination of smoke and pollutant gases, smog, is harmful for health. There are strong evidences that the Agricultural waste burning (AWB) in the Northern India leads to adverse air quality in Delhi and its surrounding regions. A severe smog episode was observed over Delhi, India during November 2012 which resulted in very low visibility and various respiratory problems. Very high values of pollutants (PM10 as high as 989 µg m-3, PM2.5 as high as 585 µg m-3 an NO2 as high as 540 µg m-3) were measured all over Delhi during the smog episode. Ultra Violet Aerosol Index (UVAI) from Aura satellite and Aerosol Optical Depth (AOD) are used in the present study along with the output trajectories from HYSPLIT model and the in-situ data. Satellite data also reveal that AOD, UVAI are always at its highest during the farmfires duration in Punjab region of India and the extent of these farmfires may be increasing. It is observed that during the smog episode all the AOD, UVAI, PM2.5 and PM10 values surpassed those of the Diwali period (one of the most polluted events in the city) by a considerable amount at all stations across Delhi. The parameters used from the remote sensing data and the ground based observations at various stations across Delhi are very well in agreement about the intensity of Smog episode. The analysis clearly shows that regional pollution can have greater contributions in deteriorating the air quality than the local under adverse meteorological conditions.

Keywords: smog, farmfires, AOD, remote sensing

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Authors: Bao Shu-Feng, Lou Yan, Dong Zhi-Liang, Mo Hai-Hong, Chen Ping-Shan

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For soft foundation filled by newly dredged mud, after improved by Vacuum Preloading Technology (VPT), the soil strength was increased only a little, the effective improved depth was small, and the ground bearing capacity is still low. To analyze the causes in depth, it was conducted in laboratory of several comparative single well model experiments of VPT. It was concluded: (1) it mainly caused serious clogging problem and poor drainage performance in vertical drains of high content of fine soil particles and strong hydrophilic minerals in dredged mud, too fast loading rate at the early stage of vacuum preloading (namely rapidly reaching-80kPa) and too small characteristic opening size of the filter of the existed vertical drains; (2) it commonly reduced the drainage efficiency of drainage system, in turn weaken vacuum pressure in soils and soil improvement effect of the greater partial loss and friction loss of vacuum pressure caused by larger curvature of vertical drains and larger transfer resistance of vacuum pressure in horizontal drain.

Keywords: newly dredged mud, single well model experiments of vacuum preloading technology, poor drainage performance of vertical drains, poor soil improvement effect, causes analysis

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Authors: P. Priya Madhuri, J. Kamini, S. C. Jayanthi

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Assessment of land use and transportation networks is essential for sustainable urban growth, urban planning, efficient public transportation systems, and reducing traffic congestion. The study focuses on land use, population density, and their correlation with the road network for future development. The scope of the study covers inventory and assessment of the road network dataset (line) at the city, zonal, or ward level, which is extracted from very high-resolution satellite data (spatial resolution < 0.5 m) at 1:4000 map scale and ground truth verification. Road network assessment is carried out by computing various indices that measure road coverage and connectivity. In this study, an assessment of the road network is carried out for the study region at the municipal and ward levels. In order to identify gaps, road coverage and connectivity were associated with urban land use, built-up area, and population density in the study area. Ward-wise road connectivity and coverage maps have been prepared. To assess the relationship between road network metrics, correlation analysis is applied. The study's conclusions are extremely beneficial for effective road network planning and detecting gaps in the road network at the ward level in association with urban land use, existing built-up, and population.

Keywords: road connectivity, road coverage, road network, urban land use, transportation analysis

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Authors: Musoke Ivan, Birungi Racheal

Abstract:

The construction trend is characterized by increased use of modern methods yet traditional methods are cheaper in terms of costs, in addition to the benefits it offers to the construction sector, like providing more jobs that could have been worked with the intensive machines. The purpose of this research was to assess the influence of using Traditional methods of construction (TMC) on the costs and quality of building structures and determine the different ways. Traditional methods of construction (TMC) can be applicable and integrated into the construction trend, and propose ways how this can be a success. The study adopted a quantitative method approach targeting various construction professionals like Architects, Quantity surveyors, Engineers, and Construction Managers. Questionnaires and analyses of literature were used to obtain research data and findings. Simple random sampling was used to select 40 construction professionals to which questionnaires were administered. The data was then analyzed using Microsoft Excel. The findings of the research indicate that Traditional methods of construction (TMCs) in Uganda are cheaper in terms of costs, but the quality is still low. This is attributed to a lack of skilled labour and efficient supervision while undertaking tasks leading to low quality. The study identifies strategies that would improve Traditional methods of construction (TMC), which include the employment of skilled manpower and effective supervision. It also identifies the need by stakeholders like the government, clients, and professionals to appreciate Traditional methods of construction (TMCs) and allow for a levelled ground for Traditional Methods of Construction and Modern methods of construction (MMCs).

Keywords: traditional methods of construction, integration, cost, quality

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Authors: Joshi Manisha, Shivaram, Anand Vinekar, Tanya Susan Mathews, Yeshaswini Nagaraj

Abstract:

Retinopathy of prematurity (ROP) is abnormal blood vessel development in the retina of the eye in a premature infant. The principal object of the invention is to provide a technique for detecting demarcation line and ridge detection for a given ROP image that facilitates early detection of ROP in stage 1 and stage 2. The demarcation line is an indicator of Stage 1 of the ROP and the ridge is the hallmark of typically Stage 2 ROP. Thirty Retcam images of Asian Indian infants obtained during routine ROP screening have been used for the analysis. A graphical user interface has been developed to detect demarcation line/ridge and to extract ground truth. This novel algorithm uses multilevel vessel enhancement to enhance tubular structures in the digital ROP images. It has been observed that the orientation of the demarcation line/ridge is normal to the direction of the blood vessels, which is used for the identification of the ridge/ demarcation line. Quantitative analysis has been presented based on gold standard images marked by expert ophthalmologist. Image based analysis has been based on the length and the position of the detected ridge. In image based evaluation, average sensitivity and positive predictive value was found to be 92.30% and 85.71% respectively. In pixel based evaluation, average sensitivity, specificity, positive predictive value and negative predictive value achieved were 60.38%, 99.66%, 52.77% and 99.75% respectively.

Keywords: ROP, ridge, multilevel vessel enhancement, biomedical

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Authors: Ehsan Gholamalizadeh, Jae Dong Chung

Abstract:

Solar chimney power plant is a feasible solar thermal system which produces electricity from the Sun. The objective of this study is to investigate buoyancy-driven flow and heat transfer through a built pilot solar chimney system called 'Kerman Project'. The system has a chimney with the height and diameter of 60 m and 3 m, respectively, and the average radius of its solar collector is about 20 m, and also its average collector height is about 2 m. A three-dimensional simulation was conducted to analyze the system, using computational fluid dynamics (CFD). In this model, radiative transfer equation was solved using the discrete ordinates (DO) radiation model taking into account a non-gray radiation behavior. In order to modelling solar irradiation from the sun’s rays, the solar ray tracing algorithm was coupled to the computation via a source term in the energy equation. The model was validated with comparing to the experimental data of the Manzanares prototype and also the performance of the built pilot system. Then, based on the numerical simulations, velocity and temperature distributions through the system, the temperature profile of the ground surface and the system performance were presented. The analysis accurately shows the flow and heat transfer characteristics through the pilot system and predicts its performance.

Keywords: buoyancy-driven flow, computational fluid dynamics, heat transfer, renewable energy, solar chimney power plant

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Authors: ِAbdallah A. A. Shaheen

Abstract:

Gaza Strip faces economic and political issues such as conflict, siege and urbanization; all these have led to an increase in the air pollution over Gaza Strip. In this study, Particulate matter 10 (PM10) concentration over Gaza Strip has been estimated by Landsat Thematic Mapper (TM) and Landsat Enhanced Thematic Mapper Plus (ETM+) data, based on a multispectral algorithm. Simultaneously, in-situ measurements for the corresponding particulate are acquired for selected time period. Landsat and ground data for eleven years are used to develop the algorithm while four years data (2002, 2006, 2010 and 2014) have been used to validate the results of algorithm. The developed algorithm gives highest regression, R coefficient value i.e. 0.86; RMSE value as 9.71 µg/m³; P values as 0. Average validation of algorithm show that calculated PM10 strongly correlates with measured PM10, indicating high efficiency of algorithm for the mapping of PM10 concentration during the years 2000 to 2014. Overall results show increase in minimum, maximum and average yearly PM10 concentrations, also presents similar trend over urban area. The rate of urbanization has been evaluated by supervised classification of the Landsat image. Urban sprawl from year 2000 to 2014 results in a high concentration of PM10 in the study area.

Keywords: PM10, landsat, atmospheric reflectance, Gaza strip, urbanization

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Authors: Maryam Rasool, Farhan Munir, Fahad Nawaz, Saad Ahmad

Abstract:

A patch antenna operating in the Ultra-Wide Band of frequency (3.1 GHz – 10.6 GHz) is designed with enhanced security from interference from other applications by incorporating the notching technique. Patch antennas in the Ultra-Wide Band are becoming widely famous due to their low power, light weight and high data rate capability. Micro strip patch antenna’s patch can be altered to increase its bandwidth and introduce UWB character in it. The designed antenna is a patch antenna consisting of a conductive sheet of metal mounted over a large sheet of metal called the ground plane with a substrate separating the two. Notched bands are public safety WLAN, WLAN and FSS. Different techniques used to implement the UWB antenna were individually implemented and there results were examined. V shaped patch was then chosen and modified to an arrow shaped patch to give the optimized results operating on the entire UWB region with considerable return loss. The frequency notch prevents the operation of the antenna at a particular range of frequency, hence minimizing interference from other systems. There are countless techniques for introducing the notch but we have used inverted C-shaped slots in the UWB patch to get the notch characteristics as output and also wavelength resonators to introduce notch in UWB band. The designed antenna is simulated in High Frequency Structural Simulator (HFSS) 13.0 by Ansoft.

Keywords: HFSS, Notch, UWB, WLAN

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Authors: S. Pooja Pragati, B. Sudarsan, S. Rajkumar

Abstract:

Silver nanoparticles (AgNP) are known for their excellent antimicrobial agents, and thus can be used as alternative disinfectant agents. However, released silver nanoparticles is a threat to naturally occurring microorganisms. This paper exhibits information on the environmental fate, toxicological effects, and application of AgNP and the current estimate on the physicochemical and antimicrobial properties of AgNP in different aqueous solutions, as well as their application as alternative disinfectants in water-treatment systems. It also gives a better approximation and experimental data of AgNP’s antimicrobial properties at different water chemistry conditions. A saturation-type fitting curve was established, showing the survival of bacteria under different water chemistry conditions as a function of the size of the nanoparticles. The results obtained show that silver nanoparticles in surface water, ground water, and brackish water are stable. The paper demonstrates the comparative study of AgNP-impregnated point-of-use ceramic water filters and ceramic filters impregnated with silver nitrate. It is observed that AgNP-impregnated ceramic water filters are more appropriate for this application due to the lesser amount of silver desorbed. Experimental data of the comparison of a polymer-based quaternary amine functionalized silsesquioxanes compound and AgNP are also tabulated and conclusions are analysed with the goal of optimizing. The simplicity of synthesis and application of Silver nanoparticles enables us to consider its effective modified version for the purification of water.

Keywords: disinfectant agent, purification of water, nano particles, water treatment

Procedia PDF Downloads 337

Authors: Ali Ait Boughrous, Said Benyoussef, Hossain El Ouarghi, Moulay Abdelazize Aboulhassan, Samah Aitbnichou, Said Benguamra

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The Rhiss-Nekor aquifer represents a primary water source for the central Rif region. Many operating structures were built for irrigation and drinking water supply. Because of the vulnerability of this aquifer, a thorough knowledge of the environment is needed to evaluate and protect resources. This work aims at the quality assessment of the water table of the plain Ghiss-Nekor and determination of pollution sources in order to establish a map of the web. The plain-Rhiss Nekor, with an area of 100 km2, is located on the Mediterranean coast of Morocco. It has a particular geological structure resulting from the opening of a graben at the end of the Tertiary, which is filled by the accumulation of hundreds of meters of sediment, generating considerable heterogeneity in deposits. This heterogeneity gives various hydrodynamic properties within the aquifer of the plain. The analysis of the water quality of twenty water points, well distributed over the plain, showed high natural salinity linked to the geological nature of the area. This salinity increases in the littoral area by the seawater intrusion phenomenon. This is accentuated by overexploitation of the ground water due to the growing demand. Some wells, located inland, are characterized by organic pollution caused by wastewater seepage from septic tanks and lost wells widespread in the region.

Keywords: anthropogenic factors, groundwater quality, marine intrusion, Rhiss-Nekor aquifer

Procedia PDF Downloads 142