Search results for: sediment rating curve
1621 Instability Index Method and Logistic Regression to Assess Landslide Susceptibility in County Route 89, Taiwan
Authors: Y. H. Wu, Ji-Yuan Lin, Yu-Ming Liou
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This study aims to set up the landslide susceptibility map of County Route 89 at Ren-Ai Township in Nantou County using the Instability Index Method and Logistic regression. Seven susceptibility factors including Slope Angle, Aspect, Elevation, Distance to fold, Distance to River, Distance to Road and Accumulated Rainfall were obtained by GIS based on the Typhoon Toraji landslide area identified by Industrial Technology Research Institute in 2001. To calculate the landslide percentage of each factor and acquire the weight and grade the grid by means of Instability Index Method. In this study, landslide susceptibility can be classified into four grades: high, medium high, medium low and low, in order to determine the advantages and disadvantages of the two models. The precision of this model is verified by classification error matrix and SRC curve. These results suggest that the logistic regression model is a preferred method than instability index in the assessment of landslide susceptibility. It is suitable for the landslide prediction and precaution in this area in the future.Keywords: instability index method, logistic regression, landslide susceptibility, SRC curve
Procedia PDF Downloads 2911620 Reducing Uncertainty of Monte Carlo Estimated Fatigue Damage in Offshore Wind Turbines Using FORM
Authors: Jan-Tore H. Horn, Jørgen Juncher Jensen
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Uncertainties related to fatigue damage estimation of non-linear systems are highly dependent on the tail behaviour and extreme values of the stress range distribution. By using a combination of the First Order Reliability Method (FORM) and Monte Carlo simulations (MCS), the accuracy of the fatigue estimations may be improved for the same computational efforts. The method is applied to a bottom-fixed, monopile-supported large offshore wind turbine, which is a non-linear and dynamically sensitive system. Different curve fitting techniques to the fatigue damage distribution have been used depending on the sea-state dependent response characteristics, and the effect of a bi-linear S-N curve is discussed. Finally, analyses are performed on several environmental conditions to investigate the long-term applicability of this multistep method. Wave loads are calculated using state-of-the-art theory, while wind loads are applied with a simplified model based on rotor thrust coefficients.Keywords: fatigue damage, FORM, monopile, Monte Carlo, simulation, wind turbine
Procedia PDF Downloads 2591619 Investigation into Relationship between Spaced Repetitions and Problems Solving Efficiency
Authors: Sidharth Talan, Rajlakshmi G. Majumdar
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Problem-solving skill is one the few skills which is constantly endeavored to improve upon by the professionals and academicians around the world in order to sustain themselves in the ever-growing competitive environment. The given paper focuses on evaluating a hypothesized relationship between the problems solving efficiency of an individual with spaced repetitions, conducted with a time interval of one day over a period of two weeks. The paper has utilized uni-variate regression analysis technique to assess the best fit curve that can explain the significant relationship between the given two variables. The paper has incorporated Anagrams solving as the appropriate testing process for the analysis. Since Anagrams solving involves rearranging a jumbled word to form a correct word, it projects to be an efficient process to observe the attention span, visual- motor coordination and the verbal ability of an individual. Based on the analysis for a sample population of 30, it was observed that problem-solving efficiency of an individual, measured in terms of the score in each test was found to be significantly correlated with time period measured in days.Keywords: Anagrams, histogram plot, moving average curve, spacing effect
Procedia PDF Downloads 1651618 Determining Sources of Sediments at Nkula Dam in the Middle Shire River, Malawi, Using Mineral Magnetic Approach
Authors: M. K. Mzuza, W. Zhang, L. S. Chapola, M. Tembo
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Shire River is the largest and longest river in Malawi emptying its water into the Zambezi River in Mozambique. Siltation is now a major problem in the Shire River due to catchment degradation. This study analysed soil samples from tributaries of the Shire River to determine sources of sediments that cause siltation using the mineral magnetic approach. Bulk sediments and separated particle size fractions of representative samples were collected from tributaries on the western and eastern sides of the Shire River, and Nkula Dam. Eastern tributaries showed relatively higher ferrimagnetic mineral contents and ferrimagnetic to anti ferromagnetic ratios than western tributaries. Sediments from both sides of the Shire River were distinguished by χARM, SIRM versus χlf and S-100 versus SIRM. Findings in this study showed that most of the sediments originated from the western part of the Shire River. Tributaries on the eastern side of the Shire River had higher values for concentration related parameters (χlf, χfd, χARM, SIRM, HIRM, S-100, and χARM/SIRM) than tributaries on the western side. Bulky and detailed magnetic measurements carried out on particle size fractions provided additional confirmation of magnetic contrasts between the two sides of the river suggesting differences in lithology, topography, climate and weather regimes in the catchments. This study demonstrated that the magnetic approach can provide a reliable means of understanding major sediment sources of Nkula Dam and similar situations. It can also help to assess future variations in sediment composition resulting from catchment changesKeywords: ferrimagnetic minerals, Shire River, tributaries rivers, particle size , topography
Procedia PDF Downloads 4681617 Analysis of Causality between Economic Growth and Carbon Emissions: The Case of Mexico 1971-2011
Authors: Mario Gómez, José Carlos Rodríguez
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This paper analyzes the Environmental Kuznets Curve (EKC) hypothesis to test the causality relationship between economic activity, trade openness and carbon dioxide emissions in Mexico (1971-2011). The results achieved in this research show that there are three long-run relationships between production, trade openness, energy consumption and carbon dioxide emissions. The EKC hypothesis was not verified in this research. Indeed, it was found evidence of a short-term unidirectional causality from GDP and GDP squared to carbon dioxide emissions, from GDP, GDP squared and TO to EC, and bidirectional causality between TO and GDP. Finally, it was found evidence of long-term unidirectional causality from all variables to carbon emissions. These results suggest that a reduction in energy consumption, economic activity, or an increase in trade openness would reduce pollution.Keywords: causality, cointegration, energy consumption, economic growth, environmental Kuznets curve
Procedia PDF Downloads 3511616 Damage Cost for Private Property by Extreme Wind over the past 10 Years in Korea
Authors: Gou-Moon Choi, Woo-Young Jung, Chan-Young Yune
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Recently, the natural disaster has increased worldwide. In Korea, the damage to life and property caused by a typhoon, heavy rain, heavy snow, and an extreme wind also increases every year. Among natural disasters, the frequency and the strength of wind have increased because sea surface temperature has risen due to the increase of the average temperature of the Earth. In the case of extreme wind disaster, it is impossible to control or reduce the occurrence, and the recovery cost always exceeds the damage cost. Therefore, quantitative estimation of the damage cost for extreme wind needs to be established beforehand to install proactive countermeasures. In this study, the damage cost for private properties was analyzed based on the data for the past 10 years in Korea. The damage cost curve was also suggested for the metropolitan cities and provinces. The result shows the possibility for the regional application of the damage cost curve because the damage cost of the regional area is estimated based on the cost of cities and provinces.Keywords: damage cost, extreme wind, natural disaster, private property
Procedia PDF Downloads 3051615 Evaluation of SCS-Curve Numbers and Runoff across Varied Tillage Methods
Authors: Umar Javed, Kristen Blann, Philip Adalikwu, Maryam Sahraei, John McMaine
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The soil conservation service curve number (SCS-CN) is a widely used method to assess direct runoff depth based on specific rainfall events. “Actual” estimated runoff depth was estimated by subtracting the change in soil moisture from the depth of precipitation for each discrete rain event during the growing seasons from 2021 to 2023. Fields under investigation were situated in a HUC-12 watershed in southeastern South Dakota selected for a common soil series (Nora-Crofton complex and Moody-Nora complex) to minimize the influence of soil texture on soil moisture. Two soil moisture probes were installed from May 2021 to October 2023, with exceptions during planting and harvest periods. For each field, “Textbook” CN estimates were derived from the TR-55 table based on corresponding mapped land use land cover LULC class and hydrologic soil groups from web soil survey maps. The TR-55 method incorporated HSG and crop rotation within the study area fields. These textbook values were then compared to actual CN values to determine the impact of tillage practices on CN and runoff. Most fields were mapped as having a textbook C or D HSG, but the HSG of actual CNs was that of a B or C hydrologic group. Actual CNs were consistently lower than textbook CNs for all management practices, but actual CNs in conventionally tilled fields were the highest (and closest to textbook CNs), while actual CNs in no-till fields were the lowest. Preliminary results suggest that no-till practice reduces runoff compared to conventional till. This research highlights the need to use CNs that incorporate agricultural management to more accurately estimate runoff at the field and watershed scale.Keywords: curve number hydrology, hydrologic soil groups, runoff, tillage practices
Procedia PDF Downloads 491614 Evaluation of Heavy Metal Contamination and Assessment of the Suitability of Water for Irrigation: A Case Study of the Sand River, Limpopo Province, South Africa
Authors: Ngonidzashe Moyo, Mmaditshaba Rapatsa
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The primary objective of this study was to determine heavy metal contamination in the water, sediment, grass and fish in Sand River, South Africa. This river passes through an urban area and sewage effluent is discharged into it. Water from the Sand river is subsequently used for irrigation downstream of the sewage treatment works. The suitability of this water and the surrounding boreholes for irrigation was determined. This study was undertaken between January, 2014 and January, 2015. Monthly samples were taken from four sites. Sites 1 was upstream of the Polokwane Wastewater Treatment Plant, sites 2, 3 and 4 were downstream. Ten boreholes in the vicinity of the Sand River were randomly selected and the water was tested for heavy metal contamination. The concentration of heavy metals in Sand River water followed the order Mn>Fe>Pb>Cu≥Zn≥Cd. Manganese concentration averaged 0.34 mg/L. Heavy metal concentration in the sediment, grass and fish followed the order Fe>Mn>Zn>Cu>Pb>Cd. The bioaccumulation factor from grass to fish was highest in manganese (19.25), followed by zinc (16.39) and iron (14.14). Soil permeability index (PI) and sodium adsorption ratio (SAR) were used to determine the suitability of Sand River and borehole water for irrigation. The PI index for Sand River water was 75.1% and this indicates that Sand River water is suitable for irrigation of crops. The PI index for the borehole water ranged from 65.8-72.8% and again this indicates suitability of borehole water for crop irrigation. The sodium adsorption ratio also indicated that both Sand River and borehole water were suitable for irrigation. A risk assessment study is recommended to determine the suitability of the fish for human consumption.Keywords: bioaccumulation, bioavailability, heavy metals, sodium adsorption ratio
Procedia PDF Downloads 2231613 An Alternative Method for Computing Clothoids
Authors: Gerardo Casal, Miguel E. Vázquez-Méndez
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The clothoid (also known as Cornu spiral or Euler spiral) is a curve that is characterized because its curvature is proportional to its length. This property makes that it would be widely used as transition curve for designing the layout of roads and railway tracks. In this work, from the geometrical property characterizing the clothoid, its parametric equations are obtained and two algorithms to compute it are compared. The first (classical), is widely used in Surveying Schools and it is based on the use of explicit formulas obtained from Taylor expansions of sine and cosine functions. The second one (alternative) is a very simple algorithm, based on the numerical solution of the initial value problems giving the clothoid parameterization. Both methods are compared in some typical surveying problems. The alternative method does not use complex formulas and so it is conceptually very simple and easy to apply. It gives good results, even if the classical method goes wrong (if the quotient between length and radius of curvature is high), needs no subsequent translations nor rotations and, consequently, it seems an efficient tool for designing the layout of roads and railway tracks.Keywords: transition curves, railroad and highway engineering, Runge-Kutta methods
Procedia PDF Downloads 2821612 Mathematical Modeling to Reach Stability Condition within Rosetta River Mouth, Egypt
Authors: Ali Masria , Abdelazim Negm, Moheb Iskander, Oliver C. Saavedra
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Estuaries play an important role in exchanging water and providing a navigational pathway for ships. These zones are very sensitive and vulnerable to any interventions in coastal dynamics. Almost major of these inlets experience coastal problems such as severe erosion, and accretion. Rosetta promontory, Egypt is an example of this environment. It suffers from many coastal problems as erosion problem along the coastline and siltation problem inside the inlet. It is due to lack of water and sediment resources as a side effect of constructing the Aswan High dam. The shoaling of the inlet leads to hindering the navigation process of fishing boats, negative impacts to estuarine and salt marsh habitat and decrease the efficiency of the cross section to transfer the flow during emergencies to the sea. This paper aims to reach a new condition of stability of Rosetta Promontory by using coastal measures to control the sediment entering, and causes shoaling inside the inlet. These coastal measures include modifying the inlet cross section by using centered jetties, eliminate the coastal dynamic in the entrance using boundary jetties. This target is achieved by using a hydrodynamic model Coastal Modeling System (CMS). Extensive field data collection (hydrographic surveys, wave data, tide data, and bed morphology) is used to build and calibrate the model. About 20 scenarios were tested to reach a suitable solution that mitigate the coastal problems at the inlet. The results show that 360 m jetty in the eastern bank with system of sand bypass from the leeside of the jetty can stabilize the estuary.Keywords: Rosetta promontory, erosion, sedimentation, inlet stability
Procedia PDF Downloads 5871611 Well Log Sequences Stratigraphy and Potential Reservoirs of Wells KF-1and KF-2; Kribi Oil Field, Douala-Kribi-Campo Basin, Cameroon
Authors: Nkwanyang L. Takem, Christopher M. Agyingi
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Background and aim: An integrated interpretation of wireline logs and lithology of two selected wells (KF-1 and KF-2) of Kribi oil field within the southeastern offshore Douala/Kribi Campo Basin was carried out for sequence stratigraphic analysis of sediments penetrated by the wells. Methods: The stratigraphic units within the wells were subdivided into depositional sequences using characteristic well log patterns that were deposited between Tertiary Miocene to lower Cretaceous. Results: Nine (9) and eight (8) depositional sequences were identified respectively for KF-1 and KF-2. The sequences comprise LST (progradational packages), TSTs (retrogradational packages) and HSTs (aggradational packages), which reflect depositional systems deposited during different phases of base-level changes. The (LST) consists of Basin Floor Fans (BFF), Slope Fans and Channel Sands deposited when sea level was low and accommodation space lower than rate of sediment influx. TST consists of retrogradational marine shales deposited during high relative sea levels and when accommodation space was higher than rate of sediment influx. HST consisted of shoreface sands displaying mostly aggradational to progradational stacking patterns. Conclusion: The rapid facies changes between successive systems tracts provide potential stratigraphic traps. Reservoir stratification and continuity vary greatly between systems tracts and this enhanced development of stratigraphic traps in the area. Basin floor fans comprise sandstone of good reservoir quality, thus huge accumulation of HC can be trapped in this reservoirs.Keywords: Douala-Kribi-Campo Basin, reservoirs, sequence strastigraphyy, system tracks
Procedia PDF Downloads 5671610 Developing a Decision-Making Tool for Prioritizing Green Building Initiatives
Authors: Tayyab Ahmad, Gerard Healey
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Sustainability in built environment sector is subject to many development constraints. Building projects are developed under different requirements of deliverables which makes each project unique. For an owner organization, i.e., a higher-education institution, involved in a significant building stock, it is important to prioritize some of the sustainability initiatives over the others in order to align the sustainable building development with organizational goals. The point-based green building rating tools i.e. Green Star, LEED, BREEAM are becoming increasingly popular and are well-acknowledged worldwide for verifying a sustainable development. It is imperative to synthesize a multi-criteria decision-making tool that can capitalize on the point-based methodology of rating systems while customizing the sustainable development of building projects according to the individual requirements and constraints of the client organization. A multi-criteria decision-making tool for the University of Melbourne is developed that builds on the action-learning and experience of implementing Green Buildings at the University of Melbourne. The tool evaluates the different sustainable building initiatives based on the framework of Green Star rating tool of Green Building Council of Australia. For each different sustainability initiative the decision-making tool makes an assessment based on at least five performance criteria including the ease with which a sustainability initiative can be achieved and the potential of a sustainability initiative to enhance project objectives, reduce life-cycle costs, enhance University’s reputation, and increase the confidence in quality construction. The use of a weighted aggregation mathematical model in the proposed tool can have a considerable role in the decision-making process of a Green Building project by indexing the Green Building initiatives in terms of organizational priorities. The index value of each initiative will be based on its alignment with some of the key performance criteria. The usefulness of the decision-making tool is validated by conducting structured interviews with some of the key stakeholders involved in the development of sustainable building projects at the University of Melbourne. The proposed tool is realized to help a client organization in deciding that within limited resources which sustainability initiatives and practices are more important to be pursued than others.Keywords: higher education institution, multi-criteria decision-making tool, organizational values, prioritizing sustainability initiatives, weighted aggregation model
Procedia PDF Downloads 2341609 Rare Earth Doped Alkali Halide Crystals for Thermoluminescence Dosimetry Application
Authors: Pooja Seth, Shruti Aggarwal
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The Europium (Eu) doped (0.02-0.1 wt %) lithium fluoride (LiF) crystal in the form of multicrystalline sheet was gown by the edge defined film fed growth (EFG) technique. Crystals were grown in argon gas atmosphere using graphite crucible and stainless steel die. The systematic incorporation of Eu inside the host LiF lattice was confirmed by X-ray diffractometry. Thermoluminescence (TL) glow curve was recorded on annealed (AN) crystals after irradiation with a gamma dose of 15 Gy. The effect of different concentration of Eu in enhancing the thermoluminescence (TL) intensity of LiF was studied. The normalized peak height of the Eu-doped LiF crystal was nearly 12 times that of the LiF crystals. The optimized concentration of Eu in LiF was found to be 0.05wt% at which maximum TL intensity was observed with main TL peak positioned at 185 °C. At higher concentration TL intensity decreases due to the formation of precipitates in the form of clusters or aggregates. The nature of the energy traps in Eu doped LiF was analysed through glow curve deconvolution. The trap depth was found to be in the range of 0.2 – 0.5 eV. These results showed that doping with Eu enhances the TL intensity by creating more defect sites for capturing of electron and holes during irradiation which might be useful for dosimetry application.Keywords: thermoluminescence, defects, gamma radiation, crystals
Procedia PDF Downloads 3301608 Communication of Expected Survival Time to Cancer Patients: How It Is Done and How It Should Be Done
Authors: Geir Kirkebøen
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Most patients with serious diagnoses want to know their prognosis, in particular their expected survival time. As part of the informed consent process, physicians are legally obligated to communicate such information to patients. However, there is no established (evidence based) ‘best practice’ for how to do this. The two questions explored in this study are: How do physicians communicate expected survival time to patients, and how should it be done? We explored the first, descriptive question in a study with Norwegian oncologists as participants. The study had a scenario and a survey part. In the scenario part, the doctors should imagine that a patient, recently diagnosed with a serious cancer diagnosis, has asked them: ‘How long can I expect to live with such a diagnosis? I want an honest answer from you!’ The doctors should assume that the diagnosis is certain, and that from an extensive recent study they had optimal statistical knowledge, described in detail as a right-skewed survival curve, about how long such patients with this kind of diagnosis could be expected to live. The main finding was that very few of the oncologists would explain to the patient the variation in survival time as described by the survival curve. The majority would not give the patient an answer at all. Of those who gave an answer, the typical answer was that survival time varies a lot, that it is hard to say in a specific case, that we will come back to it later etc. The survey part of the study clearly indicates that the main reason why the oncologists would not deliver the mortality prognosis was discomfort with its uncertainty. The scenario part of the study confirmed this finding. The majority of the oncologists explicitly used the uncertainty, the variation in survival time, as a reason to not give the patient an answer. Many studies show that patients want realistic information about their mortality prognosis, and that they should be given hope. The question then is how to communicate the uncertainty of the prognosis in a realistic and optimistic – hopeful – way. Based on psychological research, our hypothesis is that the best way to do this is by explicitly describing the variation in survival time, the (usually) right skewed survival curve of the prognosis, and emphasize to the patient the (small) possibility of being a ‘lucky outlier’. We tested this hypothesis in two scenario studies with lay people as participants. The data clearly show that people prefer to receive expected survival time as a median value together with explicit information about the survival curve’s right skewedness (e.g., concrete examples of ‘positive outliers’), and that communicating expected survival time this way not only provides people with hope, but also gives them a more realistic understanding compared with the typical way expected survival time is communicated. Our data indicate that it is not the existence of the uncertainty regarding the mortality prognosis that is the problem for patients, but how this uncertainty is, or is not, communicated and explained.Keywords: cancer patients, decision psychology, doctor-patient communication, mortality prognosis
Procedia PDF Downloads 3291607 Texture Characteristics and Depositional Environment of the Lower Mahi River Sediment, Mainland Gujarat, India
Authors: Shazi Farooqui, Anupam Sharma
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The Mahi River (~600km long) is an important west flowing the river of Central India. It originates in Madhya Pradesh and starts flowing in NW direction and enters into the state of Rajasthan. It flows across southern Rajasthan and then enters into Gujarat and finally debouches in the Gulf of Cambay. In Gujarat state, it flows through all four geomorphic zones i.e. eastern upland zone, shallow buried piedmont zone, alluvial zone and coastal zone. In lower reaches and particularly when it is flowing under the coastal regime, it provides an opportunity to study – 1. Land–Sea interaction and role of relative sea level changes, 2. Coastal/estuarine geological process, 3. Landscape evolution in marginal areas and so on. The Late Quaternary deposits of Mainland Gujarat is appreciably studied by Chamyal and his group of MS University of Baroda, and they have established that the 30-35m thick sediment package of the Mainland Gujarat is comprised of marine, fluvial and aeolian sediments. It is also established that in the estuarine zone, the upper few meter thick sediments package is of marine nature. However, its thickness, characters and the depositional environment including the role of climate and tectonics is still not clearly defined. To understand few aspects of the above mentioned, in the present study, a 17m subsurface sediment core has been retrieved from the estuarine zone of Mahi river basin. The Multiproxy studies which include the textural analysis (grain size), Loss on ignition (LOI), Bulk and clay mineralogy and geochemical studies have been carried out. In the entire sedimentary sequence, the grain size largely varies from coarse sand to clay; however, a solitary gravel bed is also noticed. The lower part (depth 9-17m), is mainly comprised of sub equal proportion of sand and silt. The sediments mainly have bimodal and leptokurtic distribution and deposited in alternate sand-silt package, probably indicating flood deposits. Relatively low moisture (1.8%) and organic carbon (2.4%) with increased carbonate values (12%) indicate that conditions must have to remain oxidizing. The middle part (depth 9–6m) has a 1m thick gravel bed at the bottom and overlain by coarse sand to very fine sand showing fining upward sequence. The presence of gravel bed suggests some kind of tectonic activity resulting into change in base level or enhanced precipitation in the catchment region. The upper part (depth 6–0m; top part of sequence) mainly comprised of fine sand to silt size grains (with appreciable clay content). The sediment of this part is Unimodal and very leptokurtic in nature suggesting wave and winnowing process and deposited in low energy suspension environment. This part has relatively high moisture (2.1%) and organic carbon (2.7%) with decreased carbonate content (4.2%) indicating change in the depositional environment probably under estuarine conditions. The presence of chlorite along with smectite clay mineral further supports the significant marine contribution in the formation of upper part of the sequence.Keywords: grain size, statistical analysis, clay minerals, late quaternary, LOI
Procedia PDF Downloads 1811606 Renewable Energy Storage Capacity Rating: A Forecast of Selected Load and Resource Scenario in Nigeria
Authors: Yakubu Adamu, Baba Alfa, Salahudeen Adamu Gene
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As the drive towards clean, renewable and sustainable energy generation is gradually been reshaped by renewable penetration over time, energy storage has thus, become an optimal solution for utilities looking to reduce transmission and capacity cost, therefore the need for capacity resources to be adjusted accordingly such that renewable energy storage may have the opportunity to substitute for retiring conventional energy systems with higher capacity factors. Considering the Nigeria scenario, where Over 80% of the current Nigerian primary energy consumption is met by petroleum, electricity demand is set to more than double by mid-century, relative to 2025 levels. With renewable energy penetration rapidly increasing, in particular biomass, hydro power, solar and wind energy, it is expected to account for the largest share of power output in the coming decades. Despite this rapid growth, the imbalance between load and resources has created a hindrance to the development of energy storage capacity, load and resources, hence forecasting energy storage capacity will therefore play an important role in maintaining the balance between load and resources including supply and demand. Therefore, the degree to which this might occur, its timing and more importantly its sustainability, is the subject matter of the current research. Here, we forecast the future energy storage capacity rating and thus, evaluate the load and resource scenario in Nigeria. In doing so, We used the scenario-based International Energy Agency models, the projected energy demand and supply structure of the country through 2030 are presented and analysed. Overall, this shows that in high renewable (solar) penetration scenarios in Nigeria, energy storage with 4-6h duration can obtain over 86% capacity rating with storage comprising about 24% of peak load capacity. Therefore, the general takeaway from the current study is that most power systems currently used has the potential to support fairly large penetrations of 4-6 hour storage as capacity resources prior to a substantial reduction in capacity ratings. The data presented in this paper is a crucial eye-opener for relevant government agencies towards developing these energy resources in tackling the present energy crisis in Nigeria. However, if the transformation of the Nigeria. power system continues primarily through expansion of renewable generation, then longer duration energy storage will be needed to qualify as capacity resources. Hence, the analytical task from the current survey will help to determine whether and when long-duration storage becomes an integral component of the capacity mix that is expected in Nigeria by 2030.Keywords: capacity, energy, power system, storage
Procedia PDF Downloads 341605 Mechanical Properties of Lithium-Ion Battery at Different Packing Angles Under Impact Loading
Authors: Wei Zhao, Yuxuan Yao, Hao Chen
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In order to find out the mechanical properties and failure behavior of lithium-ion batteries, drop hammer impact experiments and finite element simulations are carried out on batteries with different packed angles. Firstly, a drop hammer impact experiment system, which is based on the DHR-1808 drop hammer and oscilloscope, is established, and then a drop test of individual batteries and packed angles of 180 ° and 120 ° are carried out. The image of battery deformation, force-time curve and voltage-time curve are recorded. Secondly, finite element models of individual batteries and two packed angles are established, and the results of the test and simulation are compared. Finally, the mechanical characteristics and failure behavior of lithium-ion battery modules with the packed arrangement of 6 * 6 and packing angles of 180 °, 120 °, 90 ° and 60 ° are analyzed under the same velocity with different battery packing angles, and the same impact energy with different impact velocity and different packing angles. The result shows that the individual battery is destroyed completely in the drop hammer impact test with an initial impact velocity of 3m/s and drop height of 459mm, and the voltage drops to close to 0V when the test ends. The voltage drops to 12V when packed angle of 180°, and 3.6V when packed angle of 120°. It is found that the trend of the force-time curve between simulation and experiment is generally consistent. The difference in maximum peak value is 3.9kN for a packing angle of 180° and 1.3kN for a packing angle of 120°. Under the same impact velocity and impact energy, the strain rate of the battery module with a packing angle of 180° is the lowest, and the maximum stress can reach 26.7MPa with no battery short-circuited. The research under our experiment and simulation shows that the lithium-ion battery module with a packing angle of 180 ° is the least likely to be damaged, which can sustain the maximum stress under the same impact load.Keywords: battery module, finite element simulation, power battery, packing angle
Procedia PDF Downloads 691604 Comparison of Methods for Detecting and Quantifying Amplitude Modulation of Wind Farm Noise
Authors: Phuc D. Nguyen, Kristy L. Hansen, Branko Zajamsek
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The existence of special characteristics of wind farm noise such as amplitude modulation (AM) contributes significantly to annoyance, which could ultimately result in sleep disturbance and other adverse health effects for residents living near wind farms. In order to detect and quantify this phenomenon, several methods have been developed which can be separated into three types: time-domain, frequency-domain and hybrid methods. However, due to a lack of systematic validation of these methods, it is still difficult to select the best method for identifying AM. Furthermore, previous comparisons between AM methods have been predominantly qualitative or based on synthesised signals, which are not representative of the actual noise. In this study, a comparison between methods for detecting and quantifying AM has been carried out. The results are based on analysis of real noise data which were measured at a wind farm in South Australia. In order to evaluate the performance of these methods in terms of detecting AM, an approach has been developed to select the most successful method of AM detection. This approach uses a receiver operating characteristic (ROC) curve which is based on detection of AM in audio files by experts.Keywords: amplitude modulation, wind farm noise, ROC curve
Procedia PDF Downloads 1451603 Explaining the Impact of Poverty Risk on Frailty Trajectories in Old Age Using Growth Curve Models
Authors: Erwin Stolz, Hannes Mayerl, Anja Waxenegger, Wolfgang Freidl
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Research has often found poverty associated with adverse health outcomes, but it is unclear which (interplay of) mechanisms actually translate low economic resources into poor physical health. The goal of this study was to assess the impact of educational, material, psychosocial and behavioural factors in explaining the poverty-health association in old age. We analysed 28,360 observations from 11,390 community-dwelling respondents (65+) from the Survey of Health, Ageing and Retirement in Europe (SHARE, 2004-2013, 10 countries). We used multilevel growth curve models to assess the impact of combined income- and asset poverty risk on old age frailty index levels and trajectories. In total, 61.8% of the variation of poverty risk on frailty levels could be explained by direct and indirect effects, thereby highlighting the role of material and particularly psychosocial factors, such as perceived control and social isolation. We suggest strengthening social policy and public health efforts in order to fight poverty and its deleterious effects from early age on and to broaden the scope of interventions with regard to psychosocial factors.Keywords: frailty, health inequality, old age, poverty
Procedia PDF Downloads 3331602 Seismic Fragility Functions of RC Moment Frames Using Incremental Dynamic Analyses
Authors: Seung-Won Lee, JongSoo Lee, Won-Jik Yang, Hyung-Joon Kim
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A capacity spectrum method (CSM), one of methodologies to evaluate seismic fragilities of building structures, has been long recognized as the most convenient method, even if it contains several limitations to predict the seismic response of structures of interest. This paper proposes the procedure to estimate seismic fragility curves using an incremental dynamic analysis (IDA) rather than the method adopting a CSM. To achieve the research purpose, this study compares the seismic fragility curves of a 5-story reinforced concrete (RC) moment frame obtained from both methods, an IDA method and a CSM. Both seismic fragility curves are similar in slight and moderate damage states whereas the fragility curve obtained from the IDA method presents less variation (or uncertainties) in extensive and complete damage states. This is due to the fact that the IDA method can properly capture the structural response beyond yielding rather than the CSM and can directly calculate higher mode effects. From these observations, the CSM could overestimate seismic vulnerabilities of the studied structure in extensive or complete damage states.Keywords: seismic fragility curve, incremental dynamic analysis, capacity spectrum method, reinforced concrete moment frame
Procedia PDF Downloads 4221601 Validation of Existing Index Properties-Based Correlations for Estimating the Soil–Water Characteristic Curve of Fine-Grained Soils
Authors: Karim Kootahi, Seyed Abolhasan Naeini
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The soil-water characteristic curve (SWCC), which represents the relationship between suction and water content (or degree of saturation), is an important property of unsaturated soils. The conventional method for determining SWCC is through specialized testing procedures. Since these procedures require specialized unsaturated soil testing apparatus and lengthy testing programs, several index properties-based correlations have been developed for estimating the SWCC of fine-grained soils. There are, however, considerable inconsistencies among the published correlations and there is no validation study on the predictive ability of existing correlations. In the present study, all existing index properties-based correlations are evaluated using a high quality worldwide database. The performances of existing correlations are assessed both graphically and quantitatively using statistical measures. The results of the validation indicate that most of the existing correlations provide unacceptable estimates of degree of saturation but the most recent model appears to be promising.Keywords: SWCC, correlations, index properties, validation
Procedia PDF Downloads 1761600 Capital Accumulation, Technology Diffusion and Economic Growth: An Empirical Application to Tunisian Case
Authors: Ahmed Bellakhdhar
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This paper aims to test the impact of various variables-namely, investment in physical capital, investment in human capital, openness to trade and foreign direct investments, and distance from the technology frontier-on economic growth in the Tunisian context during the period 1976-2010. Empirical results identify that the impact of human capital is significantly positive. This finding confirms the hypothesis that human capital is a main driver of economic performance through its role of improving the internal productive capacity and the absorption of foreign technology especially via foreign direct investments. The effect of FDI is significantly positive in all alternative regressions and the coefficient associated to physical capital variable is positive, but not significant overall. Concerning the import of technologically advanced equipments, our estimates show the absence of a significant direct impact on economic growth in Tunisia. Our empirical results also support the assumption of a non linear relationship between tax and growth and demonstrate the existence of an inverted-U curve between the two variables, in the spirit of the “Laffer curve”.Keywords: Endogenous growth, Human capital, Technology transfer, Absorptive capacity
Procedia PDF Downloads 1321599 Sewer Culvert Installation Method to Accommodate Underground Construction in an Urban Area with Narrow Streets
Authors: Osamu Igawa, Hiroshi Kouchiwa, Yuji Ito
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In recent years, a reconstruction project for sewer pipelines has been progressing in Japan with the aim of renewing old sewer culverts. However, it is difficult to secure a sufficient base area for shafts in an urban area because many streets are narrow with a complex layout. As a result, construction in such urban areas is generally very demanding. In urban areas, there is a strong requirement for a safe, reliable and economical construction method that does not disturb the public’s daily life and urban activities. With this in mind, we developed a new construction method called the 'shield switching type micro-tunneling method' which integrates the micro-tunneling method and shield method. In this method, pipeline is constructed first for sections that are gently curved or straight using the economical micro-tunneling method, and then the method is switched to the shield method for sections with a sharp curve or a series of curves without establishing an intermediate shaft. This paper provides the information, features and construction examples of this newly developed method.Keywords: micro-tunneling method, secondary lining applied RC segment, sharp curve, shield method, switching type
Procedia PDF Downloads 4031598 Effects of Allium Sativum Essential Oil on MIC, MBC and Growth Curve of Vibrio Parahaemolyticus ATCC 43996 and Its Thermostable Direct Hemolysin Production
Authors: Afshin Akhondzadeh Basti, Zohreh Mashak, Ali Khanjari, Mohammad Adel Rezaei, Fatemeh Mohammadkhan
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Vibrio parahaemolyticus is a halophilic bacterium and often causes gastroenteritis because of consumption of raw or inadequately cooked seafood. Studies showed a strong association of thermostable direct hemolysin (TDH) produced by members of this species with its pathogenicity. The effects of garlic (Allium sativum) essential oil at concentrations of 0, 0.005, 0.015, 0.03 and 0.045% on the minimum inhibitiotory concentration (MIC), minimum bactericidal concentration (MBC), growth curve and production of TDH toxin of vibrio parahaemolyticus were studied in BHI model. MIC and MBC of Allium sativum essential oil was estimated 0.03%. The results of this study revealed that the TDH production was significantly affected by Allium sativum EO and titers of TDH production in 0 and 0.005 % were 1/256 whereas this titer in 0.015 % concentration of EO. Concentrations of 0.005 and 0/015 % of garlic essential oil reduced the bacterial growth rate significantly (P < 0.05) compared to the control group. According to the results Allium sativum essential oil showed to be effective against bacterial growth and production of TDH toxin. Its potential application in food systems may be suggested.Keywords: allium sativum essential oil, vibrio parahaemolyticus, TDH, consumption
Procedia PDF Downloads 4271597 Optimal Path Motion of Positional Electric Drive
Authors: M. A. Grigoryev, A. N. Shishkov, N. V. Savosteenko
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The article identifies optimal path motion of positional electric drive, for example, the feed of cold pilgering mill. It is shown that triangle is the optimum shape of the speed curve, and the ratio of its sides depends on the type of load diagram, in particular from the influence of the main drive of pilgering mill, and is not dependent on the presence of backlash and elasticity in the system. This thesis is proved analytically, and confirmed the results are obtained by a mathematical model that take into account the influence of the main drive-to-drive feed. By statistical analysis of oscillograph traces obtained on the real object allowed to give recommendations on the optimal control of the electric drive feed cold pilgering mill 450. Based on the data that the load torque depends on by hit the pipe in rolls of pilgering mill, occurs in the interval (0,6…0,75) tc, the recommended ratio of start time to the braking time is 2:1. Optimized path motion allowed get up to 25% more RMS torque for the cycle that allowed increased the productivity of the mill.Keywords: optimal curve speed, positional electric drive, cold pilgering mill 450, optimal path motion
Procedia PDF Downloads 3171596 The Effects of Music Therapy on Positive Negative Syndrome Scale, Cognitive Function, and Quality of Life in Female Schizophrenic Patients
Authors: Elmeida Effendy, Mustafa M. Amin, Nauli Aulia Lubis, P. J. Sirait
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Music therapy may have an effect on mental illnesses. This is a comparative, quasi-experimental study to examine the effect of music therapy added to standard care on Positive Negative Syndrome Scale, Cognitive Function and Quality of Life in female schizophrenic patients. 50 schizophrenic participants who were diagnosed with semistructured MINI ICD-X, were assigned into two groups received pharmacotherapy. Participants were assigned into each group of therapy by using matched allocation method. Music therapy added on to the first group. They received music therapy, using Mozart Sonata four times a week, over a period of six week. Positive and negative symptoms were measured by using Positive and Negative Syndrome Scale (PANSS). Cognitive function were measured by using Mini Mental State Examination (MMSE) and Montreal Cognitive Assessment (MOCA). All rating scale were administrated by certified skill residents every week after music therapy session. The participants who were received pharmaco-and-music therapy significantly showed greater response than who received pharmacotherapy only. The mean difference of response were -6,6164 (p=0,001) for PANNS, 2,911 (p=0,004) for MMSE, 3,618 (p=0,001) for MOCA, 4,599 (p=0,001) for SF-36. Music therapy have beneficial effects on PANSS, Cognitive Function and Quality of Life in schizophrenic patients.Keywords: music therapy, rating scale, schizophrenia, symptoms
Procedia PDF Downloads 3471595 An Analysis of Non-Elliptic Curve Based Primality Tests
Authors: William Wong, Zakaria Alomari, Hon Ching Lai, Zhida Li
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Modern-day information security depends on implementing Diffie-Hellman, which requires the generation of prime numbers. Because the number of primes is infinite, it is impractical to store prime numbers for use, and therefore, primality tests are indispensable in modern-day information security. A primality test is a test to determine whether a number is prime or composite. There are two types of primality tests, which are deterministic tests and probabilistic tests. Deterministic tests are adopting algorithms that provide a definite answer whether a given number is prime or composite. While in probabilistic tests, a probabilistic result would be provided, there is a degree of uncertainty. In this paper, we review three probabilistic tests: the Fermat Primality Test, the Miller-Rabin Test, and the Baillie-PSW Test, as well as one deterministic test, the Agrawal-Kayal-Saxena (AKS) Test. Furthermore, we do an analysis of these tests. All of the reviews discussed are not based on the Elliptic Curve. The analysis demonstrates that, in the majority of real-world scenarios, the Baillie- PSW test’s favorability stems from its typical operational complexity of O(log 3n) and its capacity to deliver accurate results for numbers below 2^64.Keywords: primality tests, Fermat’s primality test, Miller-Rabin primality test, Baillie-PSW primality test, AKS primality test
Procedia PDF Downloads 881594 Impact Tensile Mechanical Properties of 316L Stainless Steel at Different Strain Rates
Authors: Jiawei Chen, Jia Qu, Dianwei Ju
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316L stainless steel has good mechanical and technological properties, has been widely used in shipbuilding and aerospace manufacturing. In order to understand the effect of strain rate on the yield limit of 316L stainless steel and the constitutive relationship of the materials at different strain rates, this paper used the INSTRON-4505 electronic universal testing machine to study the mechanical properties of the tensile specimen under quasi-static conditions. Meanwhile, the Zwick-Roell RKP450 intelligent oscillometric impact tester was used to test the tensile specimens at different strain rates. Through the above two kinds of experimental researches, the relationship between the true stress-strain and the engineering stress-strain at different strain rates is obtained. The result shows that the tensile yield point of 316L stainless steel increases with the increase of strain rate, and the real stress-strain curve of the 316L stainless steel has a better normalization than that of the engineering stress-strain curve. The real stress-strain curves can be used in the practical engineering of impact stretch to improve its safety.Keywords: impact stretch, 316L stainless steel, strain rate, real stress-strain, normalization
Procedia PDF Downloads 2801593 Quantification of Pollution Loads for the Rehabilitation of Pusu River
Authors: Abdullah Al-Mamun, Md. Nuruzzaman, Md. Noor Salleh, Muhammad Abu Eusuf, Ahmad Jalal Khan Chowdhury, Mohd. Zaki M. Amin, Norlida Mohd. Dom
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Identification of pollution sources and determination of pollution loads from all areas are very important for sustainable rehabilitation of any contaminated river. Pusu is a small river which, flows through the main campus of International Islamic University Malaysia (IIUM) at Gombak. Poor aesthetics of the river, which is flowing through the entrance of the campus, gives negative impression to the local and international visitors. As such, this study is being conducted to find ways to rehabilitate the river in a sustainable manner. The point and non-point pollution sources of the river basin are identified. Upper part of the 12.6 km2 river basin is covered with secondary forest. However, it is the lower-middle reaches of the river basin which is being cleared for residential development and source of high sediment load. Flow and concentrations of the common pollutants, important for a healthy river, such as Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Suspended Solids (SS), Turbidity, pH, Ammoniacal Nitrogen (AN), Total Nitrogen (TN) and Total Phosphorus (TP) are determined. Annual pollution loading to the river was calculated based on the primary and secondary data. Concentrations of SS were high during the rainy day due to contribution from the non-point sources. There are 7 ponds along the river system within the campus, which are severely affected by high sediment load from the land clearing activities. On the other hand, concentrations of other pollutants were high during the non-rainy days. The main sources of point pollution are the hostels, cafeterias, sewage treatment plants located in the campus. Therefore, both pollution sources need to be controlled in order to rehabilitate the river in a sustainable manner.Keywords: river pollution, rehabilitation, point pollution source, non-point pollution sources, pollution loading
Procedia PDF Downloads 3541592 Oral Grammatical Errors of Arabic as Second Language (ASL) Learners: An Applied Linguistic Approach
Authors: Sadeq Al Yaari, Fayza Al Hammadi, Ayman Al Yaari, Adham Al Yaari, Montaha Al Yaari, Aayah Al Yaari, Sajedah Al Yaari, Salah Al Yami
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Background: When we further take Arabic grammatical issues into account in accordance with applied linguistic investigations on Arabic as Second Language (ASL) learners, a fundamental issue arises at this point as to the production of speech in Arabic: Oral grammatical errors committed by ASL learners. Aims: Using manual rating as well as computational analytic methodology to test a corpus of recorded speech by Second Language (ASL) learners of Arabic, this study aims to find the areas of difficulties in learning Arabic grammar. More specifically, it examines how and why ASL learners make grammatical errors in their oral speech. Methods: Tape recordings of four (4) Arabic as Second Language (ASL) learners who ranged in age from 23 to 30 were naturally collected. All participants have completed an intensive Arabic program (two years) and 20 minute-speech was recorded for each participant. Having the collected corpus, the next procedure was to rate them against Arabic standard grammar. The rating includes four processes: Description, analysis and assessment. Conclusions: Outcomes made from the issues addressed in this paper can be summarized in the fact that ASL learners face many grammatical difficulties when studying Arabic word order, tenses and aspects, function words, subject-verb agreement, verb form, active-passive voice, global and local errors, processes-based errors including addition, omission, substitution or a combination of any of them.Keywords: grammar, error, oral, Arabic, second language, learner, applied linguistics.
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