Search results for: soil loss

Authors: Medina Kadiri

Abstract:

Nigeria has an extensive coastline of 853 km long between latitude 4°10′ to 6°20′ N and longitude 2°45′ to 8°35′ E and situated in the Gulf of Guinea within the Guinea Current Large Marine Ecosystem. There is a substantial coastal community relying on this region for their livelihood of fishing, aquaculture, mariculture for various sea foods either for consumption or economic sustenance or both. Socio-economic study was conducted, using questionnaires and interview, to investigate the health symptoms of harmful algae experienced by these communities on consumption of sea foods. Eighteen symptoms were recorded. Of the respondents who experienced symptoms after consumption of sea foods, overall, more people (33.5%) experienced vomiting as a symptom, followed by nausea (14.03%) and then diarrhea (13.57%). Others were headache (9.95%), mouth tingling (8.6%) and tiredness (7.24%).The least were muscle pain, rashes, confusion, chills, burning sensation, breathing difficulty and balance difficulty which represented 0.45% each and the rest (dizziness, digestive tract tumors, itching, memory loss, & stomach pain) were less than 3% each. In terms of frequency, the most frequent symptom was diarrhea with 87.5% occurrence, closely followed by vomiting with 81.3%. Tiredness was 75% while nausea was 62.5% and headache 50%. Others such as dizziness, itching, memory loss, mouth tingling and stomach pain had about 40% occurrence or less. The least occurring symptoms were muscle pain, rashes, confusion, chills and balance difficulty and burning sensation occurring only once i.e 6.3%. Breathing difficulty was last but one with 12.5%. Visible symptom from seafood and the particular seafood consumed that prompted the visible symptoms, shows that 3.5% of the entire respondents who ate crab experienced various symptoms ranging from vomiting (2.4%), itching (0.5%) and headache (0.4%). For periwinkle, vomiting had 1.7%, while 1.2% represented diarrhea and nausea symptom comprised 0.8% of all the respondents who ate periwinkle. Some respondents who consumed fish shows that 0.4% of the respondents had Itching. From the respondents who preferred to consume shrimps/crayfish and crab, shrimps/crayfish, crab and periwinkle, the most common illness was tiredness (1.2%), while 0.5% had experienced diarrhea and many others. However, for most respondents who claimed to have no preference for any seafood, with 55.7% affirming this with vomiting being the highest (6.1%), followed closely by mouth tingling/ burning sensation (5.8%). Examining the seasonal influence on visible symptoms revealed that vomiting occurred more in the month of January with 5.5%, while headache and itching were predominant in October with (2.8%). Nausea has 3.1% in January than any season of the year, 2.6% of the entire respondents opined to have experience diarrhea in October than in any other season of the year. Regular evaluation of harmful algal poisoning symptoms is recommended for coastal communities.

Keywords: coastal, harmful algae, human poisoning symptoms, Nigeria, phycotoxins

Procedia PDF Downloads 289

Authors: Tarek Aly

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The shoulder is the most mobile joint whose stability requires the interaction of both dynamic and static stabilizers. Its wide range of movement predisposes to a high susceptibility to dislocation, accounting for nearly 50% of all dislocations. This trauma typically results in ligament injury (e.g., labral tear, capsular strain) or bony fracture (e.g., loss of glenoid or humeral head bone), which frequently causes recurrent instability. Patients with significant glenoid defects may require Latarjet procedure, which involves transferring the coracoid to the antero-inferior glenoid rim. In spite of outstanding results, 15 to 30% of cases suffer complications. In this article, we discuss the diagnosis of recurrent shoulder instability, the surgical technique and various complications of Latarjet procedure.

Keywords: recurrent, anterior gleno-humeral instability, latarjet, unstable shoulder

Procedia PDF Downloads 88

Authors: S. A. Naeini, M. Ghorbani Tochaee

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The aim of this study is to assess the influence of plastic fines content on sand-clay mixtures on maximum shear modulus and liquefaction resistance using a series of resonant column tests. A high plasticity clay called bentonite was added to 161 Firoozkooh sand at the percentages of 10, 15, 20, 25, 30 and 35 by dry weight. The resonant column tests were performed on the remolded specimens at constant confining pressure of 100 KPa and then the values of G_max and liquefaction resistance were investigated. The maximum shear modulus and cyclic resistance ratio (CRR) are examined in terms of fines content. Based on the results, the maximum shear modulus and liquefaction resistance tend to decrease within the increment of fine contents.

Keywords: Gmax, liquefaction, plastic fines, resonant column, sand-clay mixtures, bentonite

Procedia PDF Downloads 149

Authors: Erdal Akyol, Mutlu Alkan

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Multi criteria decision analysis (MDCA) covers both data and experience. It is very common to solve the problems with many parameters and uncertainties. GIS supported solutions improve and speed up the decision process. Weighted grading as a MDCA method is employed for solving the geotechnical problems. In this study, geotechnical parameters namely soil type; SPT (N) blow number, shear wave velocity (Vs) and depth of underground water level (DUWL) have been engaged in MDCA and GIS. In terms of geotechnical aspects, the settlement suitability of the municipal area was analyzed by the method. MDCA results were compatible with the geotechnical observations and experience. The method can be employed in geotechnical oriented microzoning studies if the criteria are well evaluated.

Keywords: GIS, spatial analysis, multi criteria decision analysis, geotechnics

Procedia PDF Downloads 463

Authors: K. K. Saju, A. R. Reghuraj

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High reflectance of surgical instruments under bright light hinders the visual clarity during laparoscopic surgical procedures leading to loss of precision and device control and creates strain and undesired difficulties to surgeons. Majority of the surgical instruments are made of surgical grade steel. Instruments with a non reflective surface can enhance the visual clarity during precision surgeries. A conversion coating of black oxide has been successfully developed 410 grade surgical stainless steel .The characteristics of the developed coating suggests the application of this technique for developing 410 grade surgical instruments with minimal reflectance.

Keywords: conversion coatings, 410 stainless steel, black oxide, reflectance

Procedia PDF Downloads 458

Authors: Enikő Bene

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Our sowing date experiment took place in the Demonstration Garden of Institution of Plant Sciences, Agricultural Center of University of Debrecen, in 2012-2014. The thesis contains data of test year 2014. Our purpose, besides several other examinations, was to observe how sowing date influences leaf area index and activity of photosynthesis of maize hybrids, and how those factors affect fruiting. In the experiment we monitored the change of the leaf area index and the photosynthesis of hybrids with four different growing seasons. The results obtained confirm that not only the environmental and agricultural factors in the growing season have effect on the yield, but also other factors like the leaf area index and the photosynthesis are determinative parameters, and all those factors together, modifying effects of each other, develop average yields

Keywords: sowing date, hybrid, leaf area index, photosynthetic capacity

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Authors: M. A. Sohaly, M. A. Elfouly

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Parkinson's disease (PD) is a heterogeneous movement disorder that often appears in the elderly. PD is induced by a loss of dopamine secretion. Some drugs increase the secretion of dopamine. In this paper, we will simply study the stability of PD models as a nonlinear delay differential equation. After a period of taking drugs, these act as positive feedback and increase the tremors of patients, and then, the differential equation has positive coefficients and the system is unstable under these conditions. We will present a set of suggested modifications to make the system more compatible with the biodynamic system. When giving a set of numerical examples, this research paper is concerned with the mathematical analysis, and no clinical data have been used.

Keywords: Parkinson's disease, stability, simulation, two delay differential equation

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Authors: M. A. Ahmadu, S. S. Rabia

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During the past few decades, energy dissipation in the ionosphere resulting from the geomagnetic activity has caused an increasing number of major disruptions of important power and communication services, malfunctions and loss of expensive facilities. Here, the electron precipitation energy, w(ep) and joule heating energy, w(jh) was used in the computation of this dissipation using Østgaard’s empirical relation from hourly geomagnetic indices of 2012, under the assumption that the magnetosphere does not store any energy, so that at the beginning of the activity t1=0 and end at t2=t, the statistical results obtained show that ionospheric dissipation varies month to month, day to day and hour to hour and estimated with a value ~3.6 w(ep), which is in agreement with experimental result.

Keywords: Ostgaard's, ionospheric dissipation, joule heating, electron precipitation, geomagnetic indices, empirical relation

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Authors: Peng Li, Er-xiang Song

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Numerical analysis of longitudinal tunnel seismic response due to spatial variation of earthquake ground motion is an important issue that cannot be ignored in the design and safety evaluation of tunnel structures. In this paper, numerical methods for analysis of tunnel longitudinal response under asynchronous seismic wave is extensively studied, including the improvement of the 1D time-domain finite element method, three dimensional numerical simulation technique for the site asynchronous earthquake response as well as the 3-D soil-tunnel structure interaction analysis. The study outcome will be beneficial to aid further research on the nonlinear meticulous numerical analysis and seismic response mechanism of tunnel structures under asynchronous earthquake motion.

Keywords: asynchronous input, longitudinal seismic response, tunnel structure, numerical simulation, traveling wave effect

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Authors: Nazli W. Hardy

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A critical component in the Internet of Things (IoT) ecosystem is the need for secure and appropriate transmission, processing, and storage of the data. Our current forms of authentication, and identity and access management do not suffice because they are not designed to service cohesive, integrated, interconnected devices, and service applications. The seemingly endless opportunities of IoT are in fact circumscribed on multiple levels by concerns such as trust, privacy, security, loss of control, and related issues. This paper considers multi-factor authentication (MFA) mechanisms and cohesive identity relationship management (IRM) standards. It also surveys messaging protocols that are appropriate for the IoT ecosystem.

Keywords: identity relation management, multifactor authentication, protocols, survey of internet of things ecosystem

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Authors: Danladi Ali, Abdullahi Mukaila

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In this work, GSM signal strength (power) was monitored in an indoor environment. Samples of the GSM signal strength was measured on mobile equipment (ME). One-dimensional multilevel wavelet is used to predict the fading phenomenon of the GSM signal measured and neural network clustering to determine the average power received in the study area. The wavelet prediction revealed that the GSM signal is attenuated due to the fast fading phenomenon which fades about 7 times faster than the radio wavelength while the neural network clustering determined that -75dBm appeared more frequently followed by -85dBm. The work revealed that significant part of the signal measured is dominated by weak signal and the signal followed more of Rayleigh than Gaussian distribution. This confirmed the wavelet prediction.

Keywords: decomposition, clustering, propagation, model, wavelet, signal strength and spectral efficiency

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Authors: Laila Almulla

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As native plants are better adapted to the local environment, can endure long spells of drought, withstand high soil salinity levels and provide a more natural effect to landscape projects, their use in landscape projects are gaining popularity. Standardization of seed germination methods and raising the hardened plants of selected native plants for their use in landscape projects will both conserve natural resources and produce sustainable greenery. In the present study, Haloxylon salicornicum, a perennial herb with a potential use for urban greenery was selected for seed germination tests as there is an urgent need to mass multiply them for their large-scale use. Among the nine treatments tried with different concentrations of gibberelic acid (GA3) and dry heat, the seeds responded with treatments when the wings were removed. The control as well as 250 GA3 treatments produced the maximum germination of 86%.

Keywords: dormancy, gibberelic acid, germination trays , vigor index

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Authors: Maryam Ehsanpour, Majid Afkhami ‎

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This study investigated the presence of hydrocarbon pollution in industrial waste water sediments found in west coast of Bandar Abass (northern part of Hormoz strait). Therefore, six transects from west of the city were selected. Each transect consists of three stations intervals 100, 600 and 1100 meter from the low tide were sampled in both the summer and winter season (July and January 2009). Physical and chemical parameters of water, concentration of total petroleum hydrocarbons (TPH) and soil tissue deposition were evaluated according to standard procedures of MOOPAM. Average results of dissolved oxygen were 6.42 mg/l, temperature 26.31°C, pH 8.55, EC 54.47 ms/cm and salinity 35.98 g/l respectively. Results indicate that minimum, maximum and average concentration of total petroleum hydrocarbons (TPH) in sediments were, 60.18, 751.83, and 229.21 µg/kg respectively which are less than comparable studies in other parts of Persian Gulf.

Keywords: oil pollution, Bandar Abbas, costal sediments, TPH ‎

Procedia PDF Downloads 719

Authors: Abouamama Sidaoui, Noureddine Karkachi, Mebrouk Kihal

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The characteristics of Fusarium oxysporium f.sp. albedinis (Foa) isolates were investigated using electrophoretic studies of isozymes systems (esterase and phosphatase). All the (F.o.a) isolates were pathogenic to the date palm seedlings cultivar Deglet Nour, but they did not induce any disease symptoms on control plants. Fusarium sp. isolated from soil did not show aggression against these seedlings. The isoenzymes profiles revealed polymorphic bands. The data were subjected to analysis with the JMP method. The isolates were delineated into two main groups A and B which were divided into sub-groups. 19 isolates create the group A, and four isolates (E1, E2, E3 and M15A) formed the group B. Analysis of isozyme banding patterns was found to be a reliable marker technology, efficient, and effective tools to find the genetic variability among isolates isolated in different geographical areas.

Keywords: genetic diversity, Fusarium oxysporium f. sp. albedinis, isozyme analysis, pathogenicity

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Authors: Cheh-Shyh Ting, Jiin-Liang Lin

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This study was conducted at the Wanglung Farm in Pingtung County to test the groundwater seepage influences on the implemented project for artificial groundwater recharge. The study was divided into three phases. The first phase, conducted on natural groundwater that was recharged through the local climate and growing conditions, observed the natural form of vegetation species. The original plants were flooded, and after 60 days it was observed that of the original plants only Goosegrass (Eleusine indica) and Black heart (Polygonum lapathifolium Linn.) remained. Direct infiltration tests were carried out, and calculations for the effect of vegetation on infiltration velocity of the recharge pool were noted. The second phase was an indoor test. Bahia grass and wild amaranth were selected as vegetation roots. After growth, the distribution of different grassroots was observed in order to facilitate a comparison permeability coefficient calculated by the amount of penetration and to explore the relationship between density and the efficiency to groundwater recharge. The third phase was the root tomography analysis, further observation of the development of plant roots using computed tomography technology. Computed Tomography, also known as (CT), is a diagnostic imaging examination, normally used in the medical field. In the first phase of the feasibility study, most non-aquatic plants wilted and died within seven days. In seven days, the remaining plants were used for experimental infiltration analysis. Results showed that in eight hours of infiltration test, Eleusine indica stems averaged 0.466 m/day and wild amaranth averaged 0.014 m/day. The second phase of the experiment was conducted on the remains of the plant a week in it had died and rotted, and the infiltration experiment was performed under these conditions. The results showed eight hours in end of the infiltration test, Eleusine indica stems averaged 0.033 m/day, and wild amaranth averaged 0.098 m/day. Non-aquatic plants died within two weeks, and their rotted remains clogged the pores of bottom soil particles, causing obstruction of recharge pool infiltration. Experiment results showed that eight hours in the test the average infiltration velocity for Eleusine indica stems was 0.0229 m/day and wild amaranth averaged 0.0117 m/day. Since the rotted roots of the plants blocked the pores of the soil in the recharge pool, which resulted in the obstruction of the artificial infiltration pond and showed an immediate impact on recharge efficiency. In order to observe the development of plant roots, the third phase used computed tomography imaging. Iodine developer was injected into the Black heart, allowing its cross-sectional images to be shown on CT and to be used to observe root development.

Keywords: artificial recharge of groundwater, computed tomography, infiltration velocity, vegetation root system

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Authors: Osama Terra, Mariesa Nel, Hatem Hussein

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Calibration of Optical Time Domain Reflectometer (OTDR) has a crucial role for the accurate determination of fault locations and the accurate calculation of loss budget of long-haul optical fibre links during installation and repair. A comparison has been made between the Egyptian National Institute for Standards (NIS-Egypt) and the National Metrology institute of South Africa (NMISA-South Africa) for the calibration of an OTDR. The distance and the attenuation scales of a transfer OTDR have been calibrated by both institutes using their standards according to the standard IEC 61746-1 (2009). The results of this comparison have been compiled in this report.

Keywords: OTDR calibration, recirculating loop, concatenated method, standard fiber

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Authors: Shaina Nagpal, Amit Gupta

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In this work, all optical Stimulated Brillouin Scattering (SBS) generated single sideband with suppressed carrier is presented to provide better efficiency. The generation of single sideband and enhanced carrier power signal using the SBS technique is further used to strengthen the low shifted sideband and to suppress the upshifted sideband. These generated single sideband signals are able to work at high frequency ranges. Also, generated single sideband is validated over 90 km transmission using single mode fiber with acceptable bit error rate. The results for an equivalent are then compared so that the acceptable technique is chosen and also the required quality for the optimum performance of the system is reported.

Keywords: stimulated Brillouin scattering, radio over fiber, upper side band, quality factor

Procedia PDF Downloads 237

Authors: Chebouti-meziou Nadjiba1, And Chebouti Yahia2:

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the cultivation of Pistachios Pistacia vera of rare plants in Algeria and this point to see the lack of knowledge of techniques, which resulted in the proliferation of the tree to obtain a limited benefit does not exceed 0.75 tons / hectare, in addition to the enemy that lead to poor product on the one hand, one of which buds into wood and fruit Chaetoptelius vestitus. Since the tree is the raw sound production, while 25 kg of infected tree produces about 15 kg of any shortage of fact that this insect Chaetoptelius vestitus spend the amount of trouble going in the summer the young twigs of the trees into a sound the product by20% and due to the composition by the problem of spending in the newly formed branches, which lead to this loss in yield

Keywords: chaetoptelius vestitus, pistacia vera, spending, return, poor product.

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Authors: Sharmeelee Subramaniam, Muhd Harris Ramli, Fauziah Ahmad

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The application of vacuum pressure to accelerate ground consolidation has been growing significantly in recent years. This ground improvement technique has its advantages, especially in areas where suitable fill is scarce, as it minimizes the surcharge fill height required for the preloading. A study was carried out to examine the response of soft subsoil subjected to vacuum consolidation in combination with embankment loading, surcharge preloading and PVD with two-way drainage. This paper shall describe a procedure to determine the optimum surcharge height and penetration depth of prefabricated vertical drains (PVD) where vacuum consolidation is combined with the use of PVD in soft clay deposits with two-way drainage.

Keywords: prefabricated vertical drain, soft soil, surcharge preload, vacuum consolidation

Procedia PDF Downloads 85

Authors: Mohan T. Harish, Masson Lauriane, Sreevalsa Kolathayar

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Environmental issues raise alarm in the constructional field which implies a need for exploring new construction materials derived from the waste and residual products. This paper presents a detailed review of the alternatives approaches employed in the construction field using plastic waste in mixture with mixed with fillers. A detailed analysis of the plastic waste used in concrete, with soil, sand, clay and natural residues like sawdust, rice husk etc are presented. The different process carried forward was also discussed along with the scrutiny of the change in mechanical properties. The effect of coupling agents in the proposed mixture has been appraised in detail which gives implications for its future application in the field of plastic waste with viable materials in composite construction blocks.

Keywords: plastic waste, composite materials, construction block, concrete, natural residue, coupling agent

Procedia PDF Downloads 254

Authors: Ambrish Singh

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The corrosion inhibition performance of pyran derivatives (AP) on mild steel in 15% HCl was investigated by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, weight loss, contact angle, and scanning electron microscopy (SEM) measurements, DFT and molecular dynamic simulation. The adsorption of APs on the surface of mild steel obeyed Langmuir isotherm. The potentiodynamic polarization study confirmed that inhibitors are mixed type with cathodic predominance. Molecular dynamic simulation was applied to search for the most stable configuration and adsorption energies for the interaction of the inhibitors with Fe (110) surface. The theoretical data obtained are, in most cases, in agreement with experimental results.

Keywords: acidizing inhibitor, pyran derivatives, DFT, molecular simulation, mild steel, EIS

Procedia PDF Downloads 199

Authors: Tadashi Watanabe, Jinya Katsuyama, Akihiro Mano

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The estimation of leak flow rates through narrow cracks in structures is of importance for nuclear reactor safety, since the leak flow could be detected before occurrence of loss-of-coolant accidents. The two-phase critical leak flow rates are calculated using the system analysis code, and two representative non-homogeneous critical flow models, Henry-Fauske model and Ransom-Trapp model, are compared. The pressure decrease and vapor generation in the crack, and the leak flow rates are found to be larger for the Henry-Fauske model. It is shown that the leak flow rates are not affected by the structural temperature, but affected largely by the roughness of crack surface.

Keywords: crack, critical flow, leak, roughness

Procedia PDF Downloads 182

Authors: Janaina Camile Pasqual Lofhagen, David Savarese, Veronika Vazhnik

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The built environment is considered as a key element in transitioning to clean energy, needed to create resilient buildings and cities, enhance their adaptability to changes, and pursue energy saving. For such energy transition, this paper presents biogas as one of the sustainable sources of energy, as it is produced from organic materials often available in both urban and rural areas and can be converted into electrical and thermal energy, or into vehicular energies fuel. The resilience benefits of this fuel is being a localized alternative energy, and also provides tangible benefits for water, air, and soil quality. Through bibliographic and empirical research, this study analyzed the biogas potential and applications in Brazil and in the U.S. The results indicated that biogas emits 85% less CO2 to the atmosphere compared to diesel and could supply 40% of domestic electricity demand and 70% of diesel consumption in Brazil, with a similar scenario for the U.S.

Keywords: resilience, sustainability, built environment, energy transition, biogas.

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Authors: S. Ravindran, Y.Liu, I. Gratchev, D.Jeng

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Rainfall-induced shallow landslides are more common in the northern New South Wales (NSW), Australia. From 2009 to 2017, around 105 rainfall-induced landslides occurred along the road corridors and caused temporary road closures in the northern NSW. Rainfall causing shallow landslides has different distributions of rainfall varying from uniform, normal, decreasing to increasing rainfall intensity. The duration of rainfall varied from one day to 18 days according to historical data. The objective of this research is to analyse slope instability of some of the sites in the northern NSW by varying cumulative rainfall using SLOPE/W and SEEP/W and compare with field data of rainfall causing shallow landslides. The rainfall data and topographical data from public authorities and soil data obtained from laboratory tests will be used for this modelling. There is a likelihood of shallow landslides if the cumulative rainfall is between 100 mm to 400 mm in accordance with field data.

Keywords: landslides, modelling, rainfall, suction

Procedia PDF Downloads 186

Authors: Yajing Jiang, Jing Wu

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Residential area construction links many problems such as population resources, ecology, social values, public services and transportation in the city. After Chinese housing reform, a large number of residential area development accompanied by the loss of agricultural and ecological land. To explore the future of Chinese urban residential area, this article concentrates on how the 'Compact Settlement' behaves in improving the living environment and saving the resources. Through the research of residential area in Hangzhou, there are some determines that increasing the development intensity of the area can indeed bring some improvement in the overall environment. In conclusion, possible design alternatives are discussed for leading Chinese urban development towards a more sustainable path.

Keywords: compact city development, environmental sustainability, residential area, Hangzhou

Procedia PDF Downloads 319

Authors: Abdulmagid A. Khattabi, Ahmed A. Hablous, Mofied M. Elnemry

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The carbon steel is of one of the most common mineral materials used in engineering and industrial applications in order to have access to the required mechanical properties, especially after the change of carbon ratio, but this may lead to stimulate corrosion. It has been used in models of solids with different carbon ratios such as 0.05% C, 0.2% C, 0.35% C, 0.5% C, and 0.65% C and have been studied using three testing durations which are 4 weeks, 6 weeks, and 8 weeks and among different corrosion environments such as atmosphere, fresh water, and salt water. This research is for the purpose of finding the effect of the carbon content on the corrosion resistance of steels in different corrosion medium by using the weight loss technique as a function of the corrosion resistance. The results that have been obtained through this research shows that a correlation can be made between corrosion rates and steel's carbon content, and the corrosion resistance decreases with the increase in carbon content.

Keywords: proportion of carbon in the steel, corrosion rate, erosion, corrosion resistance in carbon-steel

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Authors: Fekir Youcef, Mederbal Khalladi, M. A. Hamadouche, D. Anteur

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Algeria is one of the countries that are highly affected by desertification which is the consequence of several factors. For this purpose, there is a need to study this problem by quantitative approaches. In this study, we apply the MEDALUS method (Mediterranean Desertification and Land Use) to a watershed located in Saida town in semi-arid environment in the south west of Algeria. The method is based on sensitive areas identification by making use of the different parameters that may affect the desertification process such as vegetation, soil, climate and management. Spatial analyses are strong tools that allow modelization of each indicator. Results show that according to European standards, a large scale of the watershed falls into critical classes. And therefore, the modelization approach can be an effective way to study and understand the desertification showing an example of the project of the green dam that limits the desertification process to affect the north areas off Algeria.

Keywords: Algeria, desertification, MEDALUS, modelization

Procedia PDF Downloads 392

Authors: Seyed Abolhassan Naeini, Maedeh Akhavan Tavakkoli

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Evaluating the shear wave velocity (V_s) and primary wave velocity (Vₚ) is necessary to identify the ground type of the site. Identifying the soil type based on different codes can affect the dynamic analysis of geotechnical properties. This study aims to separate the underground layers at the project site based on the shear wave and primary wave velocity (Sₚ) in different depths and determine dynamic elastic modulus based on the shear wave velocity. Bandar Anzali is located in a tectonically very active area. Several active faults surround the study site. In this case, a field investigation of downhole testing is conducted as a geophysics method to identify the ground type.

Keywords: downhole, geophysics, shear wave velocity, case-study

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Authors: Volkan Isbuga, Joman M. Mahmood, Ali Firat Cabalar

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This study presents the site response analysis of mica-sand mixtures available in certain parts of the world including Izmir, a highly populated city and located in a seismically active region in western part of Turkey. We performed site response analyses by employing SHAKE, an equivalent linear approach, for the micaceous soil deposits consisting of layers with different amount of mica contents and thicknesses. Dynamic behavior of micaceous sands such as shear modulus reduction and damping ratio curves are input for the ground response analyses. Micaceous sands exhibit a unique dynamic response under a scenario earthquake with a magnitude of Mw=6. Results showed that higher amount of mica caused higher spectral accelerations.

Keywords: micaceous sands, site response, equivalent linear approach, SHAKE

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Authors: Kush Kumar, Varun Joshi

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Slope instability is a major problem of the mountainous region, especially in parts of the Indian Himalayan Region (IHR). The on-going tectonic, rugged topography, steep slope, heavy precipitation, toe erosion, structural discontinuities, and deformation are the main triggering factors of landslides in this region. Besides the loss of life, property, and infrastructure caused by a landslide, it also results in various environmental problems, i.e., degradation of slopes, land use, river quality by increased sediments, and loss of well-established vegetation. The Indian state of Uttarakhand, being a part of the active Himalayas, also faces numerous cases of slope instability. Therefore, the vulnerable landslide zones need to be delineated to safeguard various losses. The study area is focused in Garhwal and Tehri -Garhwal district of Uttarakhand state along National Highway 58, which is a strategic road and also connects the four important sacred pilgrims (Char Dham) of India. The lithology of these areas mainly comprises of sandstone, quartzite of Chakrata formation, and phyllites of Chandpur formation. The greywacke and sandstone rock of Saknidhar formation dips northerly and is overlain by phyllite of Chandpur formation. The present research incorporates the lineament density mapping using remote sensing satellite data supplemented by a detailed field study via kinematic analysis. The DEM data of ALOS PALSAR (12.5 m resolution) is resampled to 10 m resolution and used for preparing various thematic maps such as slope, aspect, drainage, hill shade, lineament, and lineament density using ARCGIS 10.6 software. Furthermore, detailed field mapping, including structural mapping, geomorphological mapping, is integrated for kinematic analysis of the slope using Dips 6.0 software of Rockscience. The kinematic analysis of 40 locations was carried out, among which 15 show the planar type of failure, five-show wedge failure, and rest, 20 show no failures. The lineament density map is overlapped with the location of the unstable slope inferred from kinematic analysis to infer the association of the field information and remote sensing derived information, and significant compatibility was observed. With the help of the present study, location-specific mitigation measures could be suggested. The mitigation measures would be helping in minimizing the probability of slope instability, especially during the rainy season, and reducing the hampering of road traffic.

Keywords: Indian Himalayan Region, kinematic analysis, lineament density mapping, slope instability

Procedia PDF Downloads 141