Search results for: control area network (CAN)
Commenced in January 2007
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Edition: International
Paper Count: 22417

Search results for: control area network (CAN)

15397 Low-Voltage Multiphase Brushless DC Motor for Electric Vehicle Application

Authors: Mengesha Mamo Wogari

Abstract:

In this paper, low voltage multiphase brushless DC motor with square wave air-gap flux distribution for electric vehicle application is proposed. Ten-phase, 5 kW motor, has been designed and simulated by finite element methods demonstrating the desired high torque capability at low speed and flux weakening operation for high-speed operations. The motor torque is proportional to number of phases for a constant phase current and air-gap flux. The concept of vector control and simple space vector modulation technique is used on MATLAB to control the motor demonstrating simple switching pattern for selected number of phases. The low voltage DC and inverter output AC are desired characteristics to avoid any electric shock in the vehicle, accidentally and during abnormal conditions. The switching devices for inverter are of low-voltage rating and cost effective though their number is equal to twice the number of phases.

Keywords: brushless DC motors, electric Vehicle, finite element methods, Low-voltage inverter, multiphase

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15396 The Effect of Early Skin-To-Skin Contact with Fathers on Their Supporting Breastfeeding

Authors: Shu-Ling Wang

Abstract:

Background: Multiple studies showed early skin-to-skin contact (SSC) with mothers was beneficial to newborns such as breastfeeding and maternal childcare. In cases of newborns unable to have early SSC with mothers, fathers’ involvement could let early SSC continue without interruption. However, few studies had explored the effects of early SSC by fathers in comparison to early SSC with mothers. Paternal involvement of early SSC should be equally important in term of childcare and breastfeeding. The purpose of this study was to evaluate the efficacy of early SSC by fathers in particular in their support of breastfeeding. Methods: A quasi-experimental design was employed by the study. One hundred and forty-four father-infant pairs had participated the study, in which infants were assigned either to SSC with their fathers (n = 72) or to routine care (n = 72) as the control group. The study was conducted at a regional hospital in northern Taiwan. Participants included parents of both vaginal delivery (VD) and caesarean section birth (CS) infants. To be eligible for inclusion, infants must be over 37-week gestational ages. Data were collected twice: as pretest upon admission and as posttest with online questionnaire during first, second, and third postpartum months. The questionnaire included items for Breastfeeding Social Support, methods of feeding, and the mother-infant 24-hour rooming-in rate. The efficacy of early SSC with fathers was evaluated using the generalized estimating equation (GEE) modeling. Research Result: The primary finding was that SSC with fathers had positive impact on fathers’ support of breastfeeding. Analysis of the online questionnaire indicated that early SSC with fathers improved the support of breastfeeding than the control group (VD: t = -4.98, p < .001; CS: t = -2.37, p = .02). Analysis of mother-infant 24-hour rooming-in rate showed that SSC with fathers after CS had a positive impact on the rooming-in rate (χ² = 5.79, p = .02); however, with VD the difference between early SSC with fathers and the control group was insignificant (χ² = .23, p = .63). Analysis of the rate of exclusive breastfeeding indicated that early SSC with fathers had a higher rate than the control group during first three postpartum months for both delivery methods (VD: χ² = 12.51, p < .001 on 1st postpartum month, χ² = 8.13, p < .05 on 2nd postpartum month, χ² = 4.43, p < .05 on 3rd postpartum month; CS: χ² = 6.92, p < .05 on 1st postpartum month, χ² = 7.41, p < .05 on 2nd postpartum month, χ² = 6.24, p < .05 on 3rd postpartum month). No significant difference was found on the rate of exclusive breastfeeding with both methods of delivery between two groups during hospitalization. (VD: χ² =2 .00, p = .16; CS: χ² = .73, p = .39). Conclusion: Implementing early SSC with fathers has many benefits to both parents. The result of this study showed increasing fathers’ support of breastfeeding. This encourages our nursing personnel to focus the needs of father during breastfeeding, therefore further enhancing the quality of parental care, the rate and duration of breastfeeding.

Keywords: breastfeeding, skin-to-skin contact, support of breastfeeding, rooming-in

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15395 Sea Level Rise and Implications for Low-lying areas: Coastal Evolution and Impact of Future Sea Level Rise Scenarios in Mirabello Gulf - NE Crete

Authors: Maria Kazantzaki, Evangelos Tsakalos, Eleni Filippaki, Yannis Bassiakos

Abstract:

Mediterranean areas are characterized by intense seismic and volcanic activity as well as eustatic changes, the result of which is the creation of particularly vulnerable coastal zones. The most vulnerable are low-lying coastal areas, the geomorphological evolution of which are highly affected by natural processes and anthropogenic interventions. Therefore, assessing changes that take place along coastal zones is of great importance in order to enable the development of integrated coastal management plans. A characteristic case is the gulf of Mirabello in N.E Crete, where intense coastal erosion, in combination with the tectonic subsidence of the area, threatens a large part of the coastal zone, resulting in direct socio-economic impacts. The present study assesses the temporal geomorphological changes that have taken place in the coastal zone of Mirabello gulf to provide a clear frame of the coastal zone evolution over time and performs a vulnerability assessment based on the coastal vulnerability index (CVI) methodology by Thieler and Hammar-Klose, considering geological features, coastal slope, relative sea-level change, shoreline erosion/accretion rates and mean significant wave height as well as mean tide range in the area. In light of this, an impact assessment, based on three different sea level rise scenarios, is also performed and presented.

Keywords: coastal vulnerability index, coastal erosion, GIS, sea level rise

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15394 Municipal Solid Waste Management Characteristics and Management Challenges in Bauchi Metropolitan Area, Nigeria

Authors: Haruna Abdu Usman, Bashir Usman Mohammed, Mohammed Umar Jamil

Abstract:

Municipal solid waste management constitutes a serious problem bedeviling environmental protection agencies in many cities of developing countries. Most agencies do not collect the totality of the waste generated in their cities. This study presents the current solid waste management practices and problems in Bauchi metropolis, Bauchi state Nigeria. The general feature is characterized by inefficient, insufficient and irrational collection and improper disposal alternatives. The consequent environmental effects of these problems depict clogged city drains, uncollected heap of waste on road sides of residential areas, vacant plots and uncompleted buildings and highways. This contributes immensely to flooding in the city. The major challenges facing the state environmental protection agency includes; lack of collection and disposal points, technical and institutional arrangements, financial resources and general attitude of the serving public among others. The study suggested a comprehensive and integrated approach to the solid waste management which recognizes and incorporates the interventionist role of the state government, the private formal and informal waste management operators and the serving public.

Keywords: municipal solid waste, bauchi metropolitan area, environmental protection agency, solid waste management, waste disposal

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15393 Collagen Hydrogels Cross-Linked by Squaric Acid

Authors: Joanna Skopinska-Wisniewska, Anna Bajek, Marta Ziegler-Borowska, Alina Sionkowska

Abstract:

Hydrogels are a class of materials widely used in medicine for many years. Proteins, such as collagen, due to the presence of a large number of functional groups are easily wettable by polar solvents and can create hydrogels. The supramolecular network capable to swelling is created by cross-linking of the biopolymers using various reagents. Many cross-linking agents has been tested for last years, however, researchers still are looking for a new, more secure reactants. Squaric acid, 3,4-dihydroxy 3-cyclobutene 1,2- dione, is a very strong acid, which possess flat and rigid structure. Due to the presence of two carboxyl groups the squaric acid willingly reacts with amino groups of collagen. The main purpose of this study was to investigate the influence of addition of squaric acid on the chemical, physical and biological properties of collagen materials. The collagen type I was extracted from rat tail tendons and 1% solution in 0.1M acetic acid was prepared. The samples were cross-linked by the addition of 5%, 10% and 20% of squaric acid. The mixtures of all reagents were incubated 30 min on magnetic stirrer and then dialyzed against deionized water. The FTIR spectra show that the collagen structure is not changed by cross-linking by squaric acid. Although the mechanical properties of the collagen material deteriorate, the temperature of thermal denaturation of collagen increases after cross-linking, what indicates that the protein network was created. The lyophilized collagen gels exhibit porous structure and the pore size decreases with the higher addition of squaric acid. Also the swelling ability is lower after the cross-linking. The in vitro study demonstrates that the materials are attractive for 3T3 cells. The addition of squaric acid causes formation of cross-ling bonds in the collagen materials and the transparent, stiff hydrogels are obtained. The changes of physicochemical properties of the material are typical for cross-linking process, except mechanical properties – it requires further experiments. However, the results let us to conclude that squaric acid is a suitable cross-linker for protein materials for medicine and tissue engineering.

Keywords: collagen, squaric acid, cross-linking, hydrogel

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15392 Design of an Automatic Saw Cutting Machine for Wood and Aluminum

Authors: Jawad Ul Haq, Evan Mazur, Ahmed Qureshi, Mohamed Al-Hussein

Abstract:

The uses of wood in furniture, building, bridges and aluminum in transportation and construction, make aluminum and forest economy a prominent matter in North America. Machines available to date to cut the aforementioned materials are mostly industry oriented with complex structure and operations which require special training and skill. Furthermore, requirements such as pneumatics, 3-phase supply are associated with cost, maintenance, and safety hazards. Power saws are very useful tools used to cut and shape materials; however, they can cause serious hand injuries. Operator’s hands in table saw are vulnerable as they are used to guide pieces into the saw. Apart from hands, saw operator is also prone to material being kicked back out of the saw or sustain eye or respiratory injuries due to rapidly flying sawdust and other debris. In this paper, design of an automatic saw cutting machine has been proposed to ensure safety, portability, usage at domestic level and capability to cut both aluminum and wood. This paper demonstrates detailed Mechanical design in SOLIDWORKS and Control Systems using Programmable Logic Controller (PLC), based on the aforementioned design objectives.

Keywords: programmable logic controller, saw cutting, control, automation

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15391 Urban Park Green Space Planning and Construction under the Theory of Environmental Justice

Authors: Ma Chaoyang

Abstract:

This article starts from the perspective of environmental justice theory and analyzes the accessibility and regional equity of park green spaces in the central urban area of Chengdu in 2022 based on the improved Gaussian 2SFCA analysis method and Gini coefficient method. Then, according to the relevant analysis model, it further explores the correlation between the spatial distribution of park green spaces and the socio-economic conditions of residents in order to provide a reference for the construction and research of Chengdu's park city under the guidance of fairness and justice. The results show that: (1) Overall, the spatial distribution of parks and green spaces in Chengdu shows a significantly uneven distribution of extreme core edge, with a certain degree of unfairness; that is, there is an environmental injustice pattern. (2) The spatial layout of urban parks and green spaces is subject to strong guiding interference from the socio-economic level; that is, there is a high correlation between housing prices and the tendency of parks. (3) Green space resources Gini coefficient analysis shows that residents of the three modes of transportation in the study area have unequal opportunities to enjoy park and green space services, and the degree of unfairness in walking is much greater than that in cycling and cycling.

Keywords: parks and green spaces, environmental justice, two step mobile search method, Gini coefficient, spatial distribution

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15390 Non-Contact Human Movement Monitoring Technique for Security Control System Based 2n Electrostatic Induction

Authors: Koichi Kurita

Abstract:

In this study, an effective non-contact technique for the detection of human physical activity is proposed. The technique is based on detecting the electrostatic induction current generated by the walking motion under non-contact and non-attached conditions. A theoretical model for the electrostatic induction current generated because of a change in the electric potential of the human body is proposed. By comparing the obtained electrostatic induction current with the theoretical model, it becomes obvious that this model effectively explains the behavior of the waveform of the electrostatic induction current. The normal walking motions are recorded using a portable sensor measurement located in a passageway of office building. The obtained results show that detailed information regarding physical activity such as a walking cycle can be estimated using our proposed technique. This suggests that the proposed technique which is based on the detection of the walking signal, can be successfully applied to the detection of human walking motion in a secured building.

Keywords: human walking motion, access control, electrostatic induction, alarm monitoring

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15389 Analysis of High Resolution Seismic Reflection Data to Identify Different Regional Lithologies of the Zaria Batholith Located in the Basement Complex of North Central Nigeria

Authors: Collins C. Chiemeke, A. Onugba, P. Sule

Abstract:

High resolution seismic reflection has recently been carried out on Zaria batholith, with the aim of characterizing the granitic Zaria batholiths in terms of its lithology. The geology of the area has revealed that the older granite outcrops in the vicinity of Zaria are exposures of a syntectonics to late-tectonic granite batholiths which intruded a crystalline gneissic basement during the Pan-African Orogeny. During the data acquisition the geophone were placed at interval of 1 m, variable offset of 1 and 10 m was used. The common midpoint (CMP) method with 12 fold coverage was employed for the survey. Analysis of the generated 3D surface of the p wave velocities from different profiles for densities and bulk modulus revealed that the rock material is more consolidated in South East part of the batholith and less consolidated in the North Western part. This was in conformity with earlier identified geology of the area, with the South Eastern part majorly of granitic outcrop, while the North Western part is characterized with the exposure of gneisses and thick overburden cover. The difference in lithology was also confirmed by the difference in seismic sections and Arial satellite photograph. Hence two major lithologies were identified, the granitic and gneisses complex which are characterized by gradational boundaries.

Keywords: basement complex, batholith, high resolution, lithologies, seismic reflection

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15388 Effect of Endurance Exercise Training on Blood Pressure in Elderly Female Patients with Hypertension

Authors: Elham Ahmadi

Abstract:

This study is conducted with the aim of investigating the effect of moderate physical activity (60% of maximal heart rate-MHR) on blood pressure in an elderly female with hypertension. Hypertension is considered a modifiable risk factor for cardiovascular disease through physical activity. The purpose and significance of this study were to investigate the role of exercise as an alternative therapy since some patients exhibit sensitivity/intolerance to some drugs. Initially, 65 hypertensive females (average age = 49.7 years) (systolic blood pressure, SBP >140 mmHg and/or diastolic blood pressure, DBP>85 mmHg) and 25 hypertensive females as a control group (average age = 50.3 years and systolic blood pressure, SBP >140 mmHg and/or diastolic blood pressure, DBP>85 mmHg) were selected. The subjects were divided based on their age, duration of disease, physical activity, and drug consumption. Then, blood pressure and heart rate (HR) were measured in all of the patients using a sphygmomanometer (pre-test). The exercise sessions consisted of warm-up, aerobic activity, and cooling down (total duration of 20 minutes for the first session up to 55 minutes in the last session). At the end of the 12th session (mid-test) and final session (24th session), blood pressure was measured for the last time (post-test). The control group was without any exercise during the study. The results were analyzed using a t-test. Our results indicated that moderate physical activity was effective in lowering blood pressure by 6.4/5.6–mm Hg for SBP and 2.4/4.3mm Hg for DBP in hypertensive patients, irrespective of age, duration of disease, and drug consumption ( P<.005). The control group indicates no changes in BP. Physical activity programs with moderate intensity (approximately at 60% MHR), three days per week, can be used not only as a preventive measure for diastolic hypertension (DBP>90 mmHg high blood pressure) but also as an alternative to drug therapy in the treatment of hypertension, as well.

Keywords: endurance exercise, elderly female, hypertension, physical activity

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15387 Probing Extensive Air Shower Primaries and Their Interactions by Combining Individual Muon Tracks and Shower Depth

Authors: Moon Moon Devi, Ran Budnik

Abstract:

The current large area cosmic ray detector surface arrays typically measure only the net flux and arrival-time of the charged particles produced in an extensive air shower (EAS). Measurement of the individual charged particles at a surface array will provide additional distinguishing parameters to identify the primary and to map the very high energy interactions in the upper layers of the atmosphere. In turn, these may probe anomalies in QCD interactions at energies beyond the reach of current accelerators. The recent attempts of studying the individual muon tracks are limited in their expandability to larger arrays and can only probe primary particles with energy up to about 10^15.5 eV. New developments in detector technology allow for a realistic cost of large area detectors, however with limitations on energy resolutions, directional information, and dynamic range. In this study, we perform a simulation study using CORSIKA to combine the energy spectrum and lateral spread of the muons with the longitudinal depth (Xmax) of an EAS initiated by a primary at ultra high energies (10¹⁶ – 10¹⁹) eV. Using proton and iron as the shower primaries, we show that the muon observables and Xmax together can be used to distinguish the primary. This study can be used to design a future detector for the surface array, which will be able to enhance our knowledge of primaries and QCD interactions.

Keywords: ultra high energy extensive air shower, muon tracking, air shower primaries, QCD interactions

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15386 Macular Ganglion Cell Inner Plexiform Layer Thinning

Authors: Hye-Young Shin, Chan Kee Park

Abstract:

Background: To compare the thinning patterns of the ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) as measured using Cirrus high-definition optical coherence tomography (HD-OCT) in patients with visual field (VF) defects that respect the vertical meridian. Methods: Twenty eyes of eleven patients with VF defects that respect the vertical meridian were enrolled retrospectively. The thicknesses of the macular GCIPL and pRNFL were measured using Cirrus HD-OCT. The 5% and 1% thinning area index (TAI) was calculated as the proportion of abnormally thin sectors at the 5% and 1% probability level within the area corresponding to the affected VF. The 5% and 1% TAI were compared between the GCIPL and pRNFL measurements. Results: The color-coded GCIPL deviation map showed a characteristic vertical thinning pattern of the GCIPL, which is also seen in the VF of patients with brain lesions. The 5% and 1% TAI were significantly higher in the GCIPL measurements than in the pRNFL measurements (all P < 0.01). Conclusions: Macular GCIPL analysis clearly visualized a characteristic topographic pattern of retinal ganglion cell (RGC) loss in patients with VF defects that respect the vertical meridian, unlike pRNFL measurements. Macular GCIPL measurements provide more valuable information than pRNFL measurements for detecting the loss of RGCs in patients with retrograde degeneration of the optic nerve fibers.

Keywords: brain lesion, macular ganglion cell, inner plexiform layer, spectral-domain optical coherence tomography

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15385 Identifying a Drug Addict Person Using Artificial Neural Networks

Authors: Mustafa Al Sukar, Azzam Sleit, Abdullatif Abu-Dalhoum, Bassam Al-Kasasbeh

Abstract:

Use and abuse of drugs by teens is very common and can have dangerous consequences. The drugs contribute to physical and sexual aggression such as assault or rape. Some teenagers regularly use drugs to compensate for depression, anxiety or a lack of positive social skills. Teen resort to smoking should not be minimized because it can be "gateway drugs" for other drugs (marijuana, cocaine, hallucinogens, inhalants, and heroin). The combination of teenagers' curiosity, risk taking behavior, and social pressure make it very difficult to say no. This leads most teenagers to the questions: "Will it hurt to try once?" Nowadays, technological advances are changing our lives very rapidly and adding a lot of technologies that help us to track the risk of drug abuse such as smart phones, Wireless Sensor Networks (WSNs), Internet of Things (IoT), etc. This technique may help us to early discovery of drug abuse in order to prevent an aggravation of the influence of drugs on the abuser. In this paper, we have developed a Decision Support System (DSS) for detecting the drug abuse using Artificial Neural Network (ANN); we used a Multilayer Perceptron (MLP) feed-forward neural network in developing the system. The input layer includes 50 variables while the output layer contains one neuron which indicates whether the person is a drug addict. An iterative process is used to determine the number of hidden layers and the number of neurons in each one. We used multiple experiment models that have been completed with Log-Sigmoid transfer function. Particularly, 10-fold cross validation schemes are used to access the generalization of the proposed system. The experiment results have obtained 98.42% classification accuracy for correct diagnosis in our system. The data had been taken from 184 cases in Jordan according to a set of questions compiled from Specialists, and data have been obtained through the families of drug abusers.

Keywords: drug addiction, artificial neural networks, multilayer perceptron (MLP), decision support system

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15384 Immediate Effect of Transcutaneous Electrical Nerves Stimulation on Flexibility and Health Status in Patients with Chronic Nonspecific Low Back Pain (A Pilot Study)

Authors: Narupon Kunbootsri, Patpiya Sirasaporn

Abstract:

Low back pain is the most common of chief complaints in chronic pain. Low back pain directly affect to activities daily living and also has high socioeconomic costs. The prevalence of low back pain is high in both genders in all populations. The symptoms of low back pain including, pain at low back area, muscle spasm, tenderness points and stiff back. Trancutanous Electrical Nerve Stimulation (TENS) is one of modalities mainly use for control pain. There was indicated that TENS is wildly use in low back pain, but no scientific data about the flexibility of muscle after TENS in low back pain. Thus the aim of this study was to investigate immediate effect of TENS on flexibility and health status in patients with chronic nonspecific low back pain. Eight chronic nonspecific low back pain patients 1 male and 7 female employed in this study. Participants were diagnosed by a doctor based on history and physical examination. Each participant received treatment at physiotherapy unit. Participants completed Roland Morris Disability Questionnaire (RMDQ), numeric rating scale (NRS) and trunk flexibility before treatment. Each participant received low frequency TENS set at asymmetrical, 10 Hz, 20 minutes per point. Immediately after treatment, participants completed RNS, RMDQ and trunk flexibility again. All participants were treated by only one physiotherapist. There was a statistically significant increased in flexibility immediately after low frequency TENS [mean difference -6.37 with 95%CI were (-8.35)-(-4.39)]. There was a statistically significant decreased in numeric rating scale [mean difference 2.13 with 95%CI were 1.08-3.16]. Roland Morris Disability Questionnaire showed improvement of health status average 44.8% immediately after treatment. In conclusion, the results of the present study indicate that immediately effect after low frequency TENS can decrease pain and improve flexibility of back muscle in chronic nonspecific low back pain patients.

Keywords: low back pain, flexibility, TENS, chronic

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15383 Mineral Deposits in Spatial Planning Systems – Review of European Practices

Authors: Alicja Kot-Niewiadomska

Abstract:

Securing sustainable access to raw materials is vital for the growth of the European economy and for the goals laid down in Strategy Europe 2020. One of the most important sources of mineral raw materials are primary deposits. The efficient management of them, including extraction, will ensure competitiveness of the European economy. A critical element of this approach is mineral deposits safeguarding and the most important tool - spatial planning. The safeguarding of deposits should be understood as safeguarding of land access, and safeguarding of area against development, which may (potential) prevent the use of the deposit and the necessary mining activities. Many European Union countries successfully integrated their mineral policy and spatial policy, which has ensured the proper place of mineral deposits in their spatial planning systems. These, in turn, are widely recognized as the most important mineral deposit safeguarding tool, the essence of which is to ensure long-term access to its resources. The examples of Austria, Portugal, Slovakia, Czech Republic, Sweden, and the United Kingdom, discussed in the paper, are often mentioned as examples of good practices in this area. Although none of these countries managed to avoid cases of social and environmental conflicts related to mining activities, the solutions they implement certainly deserve special attention. And for many countries, including Poland, they can be a potential source of solutions aimed at improving the protection of mineral deposits.

Keywords: mineral deposits, land use planning, mineral deposit safeguarding, European practices

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15382 Changes in Physical Soil Properties and Crop Status on Soil Enriched With Treated Manure

Authors: Vaclav Novak, Katerina Krizova, Petr Sarec

Abstract:

Modern agriculture has to face many issues from which soil degradation and lack of organic matter in the soil are only a few of them. Apart from Climate Change, human utilization of landscape is the cause of a majority part of these problems. Cattle production in Czechia has been reduced by more than half in recent 30 years. However, cattle manure is considered as staple organic fertilizer, and its role in attempts for sustainable agriculture is irreplaceable. This study aims to describe the impact of so-called activators of biological manure transformation (Z´fix, Olmix Group) mainly on physical soil properties but also on crop status. The experiment has been established in 2017; nevertheless, initial measurements of implement draft have been performed before the treated manure application. In 2018, the physical soil properties and crop status (sugar beet) has been determined and compared with the untreated manure and control variant. Significant results have been observed already in the first year, where the implement draft decreased by 9.2 % within the treated manure variant in comparison with the control variant.

Keywords: field experiment, implement draft, vegetation index, sugar beet

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15381 Heat Treatment on Malaysian Hardwood Timbers: The Effect of Heat Exposure at Different Levels of Temperature on Bending Strength Properties

Authors: Nur Ilya Farhana Md Noh, Zakiah Ahmad

Abstract:

Heat treatment on timbers is a process of applying heat to modify and equip the timbers with new improvised characteristics. It is environmental friendly compared to the common practice of treating timber by chemical preservatives. Malaysian hardwood timbers; Pauh Kijang and Kapur in green condition were heat treated at 150°C, 170°C, 190°C and 210°C in a specially design electronic furnace in one hour duration. The objectives were to determine the effect of heat treatment on bending strength properties of heat treated Pauh Kijang and Kapur in term of Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) and to examine the significance changes at each temperature levels applied. Untreated samples for each species were used as a control sample. The results indicated that the bending strength properties for both species of timbers were affected by the heat exposure. Both MOE and MOR values for heat treated Pauh Kijang were increased when subjected to the specified temperature levels except at 210°C. The values were dropped compared to the control sample and sample treated at 190°C. Heat treated Kapur shows the same pattern of increment on its MOE and MOR values after exposure to heat at three temperature levels used and the values dropped at 210°C. However, differ to Pauh Kijang, even though there were decrement occurred at 210°C but the value is still higher compared to the control sample. The increments of MOE and MOR values are an indicator that heat treatment had successfully improvised the bending strength properties of these two species of hardwood timber. As the good strength of Malaysian timbers used as structural material is limited in numbers and expensive, heat treating timber with low strength properties is an alternative way to overcome this issue. Heat treatment is an alternative method need to be explored and made available in Malaysia as this country is still practicing chemical preservative treatment on the timbers.

Keywords: bending strength, hardwood timber, heat treatment, modulus of elasticity (MOE), modulus of rupture (MOR)

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15380 Geochemical Characterization of the Fahdene Formation in the Kef-Tedjerouine Area (Northwestern Tunisia)

Authors: Tahani Hallek, Dhaou Akrout, Riadh Ahmadi, Mabrouk Montacer

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The present work is an organo-geochemical study of the Fahdene Formation outcrops at the Mahjouba region belonging to the Eastern part of the Kalaat Senan structure in northwestern Tunisia (the Kef-Tedjerouine area). The analytical study of the organic content of the samples collected, allowed us to point out that the Formation in question is characterized by an average to good oil potential. This fossilized organic matter has a planktonic marine origin (type II), as indicated by the relatively high values of hydrogen index. Tmax values are in the range 440°C and attest a thermal stage of the oil window beginning. Mineralogical study found the existence of macro and micro fractures that are parallel to rock stratification or oblique with a high density. Fill standpoint, the major component of the mineralized veins is the fibrous calcite with bitumen traces. The composition of these fractures is mainly due to the availability of chemical elements scattered in the surrounding rock. As for the origin of these fractures, we assume that fluid pressure processes are heavily involved, together with the regional compressional tectonic stress regime. The Fahdene Formation has a great importance in conventional oil development as a potential source rock, and even in terms of unconventional oil exploitation through the intense fracturing allowing the percolation of gas shale and facilitating its exploitation.

Keywords: fluid pressure, fracturation, oil exploration, organic matter

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15379 Controlled Mobile Platform for Service Based Humanoid Robot System

Authors: Shrikant V. Sangludkar, Dilip I. Sangotra, Sachin T. Bagde, Abhijeet A. Khandagale

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The paper discloses a controlled tracked humanoid robot moving platform. A driving and driven wheel are controlled by a control module to drive a robot body to move according to data signals of a monitoring module, in addition, remote transmission can be achieved, and a certain remote control function can be realized. A power management module circuit board looks after in used for providing electric drive for moving of the robot body and distribution of separate power source to be used in internal of robot system. An external port circuit board is arranged, the tracked robot moving platform can be used immediately for any data acquisition. The moving platform is simple and compact in structure, strong in adaptation performance, stable in operation and suitable for being operated in severe environments. Meanwhile, a layered modular installation structure is adopted, and therefore the moving platform is convenient to assemble and disassemble.

Keywords: moving platform, humanoid robot, embedded controlled drive, mobile robot, museum robots, self-localization, obstacle avoidance, communication

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15378 Effect of Silver Diamine Fluoride on Reducing Fungal Adhesion on Dentin

Authors: Rima Zakzouk, Noriko Hiraishi, Mohamed Mahdi Alshahni, Koichi Makimura, Junji Tagami

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Background and Purpose: Silver diamine fluoride (SDF) is used to prevent and arrest dental caries. The aim of this study is to evaluate the effect of SDF on reducing Candida albicans adhesion on dentin. Materials and Methods: Bovine dentin disks (6×6 mm) were cut by Isomet and polished using grit silicon carbide papers down to 2000 in order to obtain flat dentin surfaces. Samples were divided into two groups. The first group (SDF group) was treated with 38% SDF for 3 min, while the other group (control group) did not undergo SDF treatment. All samples were exposed to C. albicans suspension, washed after 6 hours incubation at 30 °C before to be tested using XTT (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide) and real time PCR approaches. Statistical analyses of the results were performed at the significance level α = 0.05. Results: SDF inhibited C. albicans adhesion onto dentin. A significant difference was found between the SDF and control groups in both XTT and real time PCR tests. Conclusion: Using SDF to arrest the caries, could inhibit the Candida growth on dentin.

Keywords: silver diamine fluoride, dentin, real time PCR, XTT

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15377 Information and Communication Technology (ICT) Education Improvement for Enhancing Learning Performance and Social Equality

Authors: Heichia Wang, Yalan Chao

Abstract:

Social inequality is a persistent problem. One of the ways to solve this problem is through education. At present, vulnerable groups are often less geographically accessible to educational resources. However, compared with educational resources, communication equipment is easier for vulnerable groups. Now that information and communication technology (ICT) has entered the field of education, today we can accept the convenience that ICT provides in education, and the mobility that it brings makes learning independent of time and place. With mobile learning, teachers and students can start discussions in an online chat room without the limitations of time or place. However, because liquidity learning is quite convenient, people tend to solve problems in short online texts with lack of detailed information in a lack of convenient online environment to express ideas. Therefore, the ICT education environment may cause misunderstanding between teachers and students. Therefore, in order to better understand each other's views between teachers and students, this study aims to clarify the essays of the analysts and classify the students into several types of learning questions to clarify the views of teachers and students. In addition, this study attempts to extend the description of possible omissions in short texts by using external resources prior to classification. In short, by applying a short text classification, this study can point out each student's learning problems and inform the instructor where the main focus of the future course is, thus improving the ICT education environment. In order to achieve the goals, this research uses convolutional neural network (CNN) method to analyze short discussion content between teachers and students in an ICT education environment. Divide students into several main types of learning problem groups to facilitate answering student problems. In addition, this study will further cluster sub-categories of each major learning type to indicate specific problems for each student. Unlike most neural network programs, this study attempts to extend short texts with external resources before classifying them to improve classification performance. In short, by applying the classification of short texts, we can point out the learning problems of each student and inform the instructors where the main focus of future courses will improve the ICT education environment. The data of the empirical process will be used to pre-process the chat records between teachers and students and the course materials. An action system will be set up to compare the most similar parts of the teaching material with each student's chat history to improve future classification performance. Later, the function of short text classification uses CNN to classify rich chat records into several major learning problems based on theory-driven titles. By applying these modules, this research hopes to clarify the main learning problems of students and inform teachers that they should focus on future teaching.

Keywords: ICT education improvement, social equality, short text analysis, convolutional neural network

Procedia PDF Downloads 132
15376 The Use of a Rabbit Model to Evaluate the Influence of Age on Excision Wound Healing

Authors: S. Bilal, S. A. Bhat, I. Hussain, J. D. Parrah, S. P. Ahmad, M. R. Mir

Abstract:

Background: The wound healing involves a highly coordinated cascade of cellular and immunological response over a period including coagulation, inflammation, granulation tissue formation, epithelialization, collagen synthesis and tissue remodeling. Wounds in aged heal more slowly than those in younger, mainly because of comorbidities that occur as one age. The present study is about the influence of age on wound healing. 1x1cm^2 (100 mm) wounds were created on the back of the animal. The animals were divided into two groups; one group had animals in the age group of 3-9 months while another group had animals in the age group of 15-21 months. Materials and Methods: 24 clinically healthy rabbits in the age group of 3-21 months were used as experimental animals and divided into two groups viz A and B. All experimental parameters, i.e., Excision wound model, Measurement of wound area, Protein extraction and estimation, Protein extraction and estimation and DNA extraction and estimation were done by standard methods. Results: The parameters studied were wound contraction, hydroxyproline, glucosamine, protein, and DNA. A significant increase (p<0.005) in the hydroxyproline, glucosamine, protein and DNA and a significant decrease in wound area (p<0.005) was observed in the age group of 3-9 months when compared to animals of an age group of 15-21 months. Wound contraction together with hydroxyproline, glucosamine, protein and DNA estimations suggest that advanced age results in retarded wound healing. Conclusion: The decrease wound contraction and accumulation of hydroxyproline, glucosamine, protein and DNA in group B animals may be associated with the reduction or delay in growth factors because of the advancing age.

Keywords: age, wound healing, excision wound, hydroxyproline, glucosamine

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15375 Comparison of Surface Hardness of Filling Material Glass Ionomer Cement Which Soaked in Alcohol Containing Mouthwash and Alcohol-Free Mouthwash

Authors: Farid Yuristiawan, Aulina R. Rahmi, Detty Iryani, Gunawan

Abstract:

Glass ionomer cement is one of the filling material that often used in the field of dentistry because it is relatively less expensive and mostly available. Surface hardness is one of the most important properties of restoration material; it is the ability of material to stand against indentation, which is directly connected to the material compressive strength and its ability to withstand abrasion. The higher surface hardness of a material means it is better to withstand abrasion. The existence of glass ionomer cement in the mouth makes it susceptible to any substance that comes into mouth, one of them is mouthwash which is a solution that used for many purposes such as antiseptic, astringent, to prevent caries, and bad breath. The presence of alcohol in mouthwash could affect the properties of glass ionomer cement, surface hardness. Objective: To determine the comparison of surface hardness of glass ionomer cement which soaked in alcohol containing mouthwash and alcohol-free mouthwash. Methods: This research is a laboratory experimental type study. There were 30 samples made from GC FUJI IX GP EXTRA and then soaked in artificial saliva for the first 24 hours inside incubator which temperature and humidity were controlled. Samples then divided into three groups. The first group will be soaked in alcohol-containing mouthwash; second group will be soaked alcohol-free mouthwash and control group will be soaked in artificial saliva for 6 hours inside incubator. Listerine is the mouthwash that was used on this research and surface hardness was examined using Vickers Hardness Tester. The result of this research shows mean value for surface hardness of the first group is 16.36 VHN, 24.04 VHN for second group, and 43.60 VHN for control group. The result one way ANOVA with post hoc Bonferroni comparing test show significant results p = 0.00. Conclusions: The data showed there were statistically significant differences of surface hardness between each group, which surface hardness of the first group is lower than the second group, and both surface hardness of the first (alcohol mouthwash) and second group (alcohol-free mouthwash) are lowered than control group (p = 0.00).

Keywords: glass ionomer cement, mouthwash, surface hardness, Vickers hardness tester

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15374 Allometric Models for Biomass Estimation in Savanna Woodland Area, Niger State, Nigeria

Authors: Abdullahi Jibrin, Aishetu Abdulkadir

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The development of allometric models is crucial to accurate forest biomass/carbon stock assessment. The aim of this study was to develop a set of biomass prediction models that will enable the determination of total tree aboveground biomass for savannah woodland area in Niger State, Nigeria. Based on the data collected through biometric measurements of 1816 trees and destructive sampling of 36 trees, five species specific and one site specific models were developed. The sample size was distributed equally between the five most dominant species in the study site (Vitellaria paradoxa, Irvingia gabonensis, Parkia biglobosa, Anogeissus leiocarpus, Pterocarpus erinaceous). Firstly, the equations were developed for five individual species. Secondly these five species were mixed and were used to develop an allometric equation of mixed species. Overall, there was a strong positive relationship between total tree biomass and the stem diameter. The coefficient of determination (R2 values) ranging from 0.93 to 0.99 P < 0.001 were realised for the models; with considerable low standard error of the estimates (SEE) which confirms that the total tree above ground biomass has a significant relationship with the dbh. The F-test value for the biomass prediction models were also significant at p < 0.001 which indicates that the biomass prediction models are valid. This study recommends that for improved biomass estimates in the study site, the site specific biomass models should preferably be used instead of using generic models.

Keywords: allometriy, biomass, carbon stock , model, regression equation, woodland, inventory

Procedia PDF Downloads 451
15373 Impact of Sunflower Oil Supplemented Diet on Performance and Hematological Stress Indicators of Growing-Finishing Pigs Exposed to Hot Environment

Authors: Angela Cristina Da F. De Oliveira, Salma E. Asmar, Norbert P. Battlori, Yaz Vera, Uriel R. Valencia, Tâmara Duarte Borges, Antoni D. Bueno, Leandro Batista Costa

Abstract:

As homeothermic animals, pigs manifest maximum performance when kept at comfortable temperature levels, represented by a limit where thermoregulatory processes are minimal (18 - 20°C). In a stress situation where it will have a higher energy demand for thermal maintenance, the energy contribution to the productive functions will be reduced, generating health imbalances, drop in productive rates and welfare problems. The hypothesis of this project is that 5% starch replacement per 5% sunflower oil (SO), in growing and finishing pig’s diet (Iberic x Duroc), is effective as a nutritional strategy to reduce the negative impacts of thermal stress on performance and animal welfare. Seventy-two crossbred males (51± 6,29 kg body weight- BW) were housed according to the initial BW, in climate-controlled rooms, in collective pens, and exposed to heat stress conditions (30 - 32°C; 35% to 50% humidity). The experiment lasted 90 days, and it was carried out in a randomized block design, in a 2 x 2 factorial, composed of two diets (starch or sunflower oil (with or without) and two feed intake management (ad libitum and restriction). The treatments studied were: 1) control diet (5% starch x 0% SO) with ad libitum intake (n = 18); 2) SO diet (replacement of 5% of starch per 5% SO) with ad libitum intake (n = 18); 3) control diet with restriction feed intake (n = 18); or 4) SO diet with restriction feed intake (n = 18). Feed was provided in two phases, 50–100 Kg BW for growing and 100-140 Kg BW for finishing period, respectively. Hematological, biochemical and growth performance parameters were evaluated on all animals at the beginning of the environmental treatment, on the transition of feed (growing to finishing) and in the final of experiment. After the experimental period, when animals reached a live weight of 130-140 kg, they were slaughtered by carbon dioxide (CO2) stunning. Data have shown for the growing phase no statistical interaction between diet (control x SO) and management feed intake (ad libitum x restriction) on animal performance. At finishing phase, pigs fed with SO diet with restriction feed intake had the same average daily gain (ADG) compared with pigs in control diet with ad libitum feed intake. Furthermore, animals fed with the same diet (SO), presented a better feed gain (p < 0,05) due to feed intake reduce (p < 0,05) when compared with control group. To hematological and biochemical parameters, animals under heat stress had an increase in hematocrit, corpuscular volume, urea concentration, creatinine, calcium, alanine aminotransferase and aspartate aminotransferase (p < 0,05) when compared with the beginning of experiment. These parameters were efficient to characterize the heat stress, although the experimental treatments were not able to reduce the hematological and biochemical stress indicators. In addition, the inclusion of SO on pig diets improve feed gain in pigs at finishing phase, even with restriction feed intake.

Keywords: hematological, performance, pigs, welfare

Procedia PDF Downloads 284
15372 Randomized Controlled Trial of Ultrasound Guided Bilateral Intermediate Cervical Plexus Block in Thyroid Surgery

Authors: Neerja Bharti, Drishya P.

Abstract:

Introduction: Thyroidectomies are extensive surgeries involving a significant degree of tissue handling and dissection and are associated with considerable postoperative pain. Regional anaesthesia techniques have immerged as possible inexpensive and safe alternatives to opioids in the management of pain after thyroidectomy. The front of the neck is innervated by branches from the cervical plexus, and hence, several approaches for superficial and deep cervical plexus block (CPB) have been described to provide postoperative analgesia after neck surgery. However, very few studies have explored the analgesic efficacy of intermediate CPB for thyroid surgery. In this study, we have evaluated the effects of ultrasound-guided bilateral intermediate CPB on perioperative opioid consumption in patients undergoing thyroidectomy under general anesthesia. Methods: In this prospective randomized controlled study, fifty ASA grade I-II adult patients undergoing thyroidectomy were randomly divided into two groups: the study group received ultrasound-guided bilateral intermediate CPB with 10 ml 0.5% ropivacaine on each side, while the control group received the same block with 10 ml normal saline on each side just after induction of anesthesia. Anesthesia was induced with propofol, fentanyl, and vecuronium and maintained with propofol infusion titrated to maintain the BIS between 40 and 60. During the postoperative period, rescue analgesia was provided with PCA fentanyl, and the pain scores, total fentanyl consumption, and incidence of nausea and vomiting during 24 hours were recorded, and overall patient satisfaction was assessed. Results: The groups were well-matched with respect to age, gender, BMI, and duration of surgery. The difference in intraoperative propofol and fentanyl consumption was not statistically significant between groups. However, the intraoperative haemodynamic parameters were better maintained in the study group than in the control group. The postoperative pain scores, as measured by VAS at rest and during movement, were lower, and the total fentanyl consumption during 24 hours was significantly less in the study group as compared to the control group. Patients in the study group reported better satisfaction scores than those in the control group. No adverse effects of ultrasound-guided intermediate CPB block were reported. Conclusion: We concluded that ultrasound-guided intermediate cervical plexus block is a safe and effective method for providing perioperative analgesia during thyroid surgery.

Keywords: thyroidectomy, cervical plexus block, pain relief, opioid consumption

Procedia PDF Downloads 102
15371 Honey: A Remedy Rediscovered in the Treatment of Oral Diseases

Authors: Muhammad Mansoor Majeed, Imtiaz Ahmed

Abstract:

For centuries, honey has been used for the management and cure of different diseases for the treatment of wound, ulcers, burns, cough, and sore throat, etc. It has also been proved to decrease inflammation, edema, and exudates in different body tissues. This study is performed to find out the effectiveness of honey in the treatment and prevention of gingivitis, gingival bleeding, and accumulation of plaque. Randomized control trial was performed on two subject groups. Honey provided to one subject group to apply on their gums and tooth and then gargle with water and drink. Frequency of the procedure is thrice a day for a month. Another group was given a placebo. Before and after, readings were taken according to Loe and Silness Plaque and Gingival Index. Initially, the mean plaque index, Gingival index and the percentage of sites which were bleeding in the honey group was 0.910, 0.800 and 58.71% respectively which has reduced to 0.313, 0.296 and 27.6% in 30 ± 3 days whereas the control group did not show signs of improvement. Visible changed has observed in the honey group from 0.910 to 0.313 in mean plaque index, 0.800 to 0.296 in Gingival Index, and the percentage of bleeding sited decreased from 58.71% to 27.6%. No significant changes observed in another group. We can conclude that honey reduces the formation/accumulation of plaque and decreases gingival bleeding as well as it has therapeutic effects.

Keywords: honey, gingivitis, Pakistan, bleeding gums

Procedia PDF Downloads 139
15370 Development of Three-Dimensional Groundwater Model for Al-Corridor Well Field, Amman–Zarqa Basin

Authors: Moayyad Shawaqfah, Ibtehal Alqdah, Amjad Adaileh

Abstract:

Coridoor area (400 km2) lies to the north – east of Amman (60 km). It lies between 285-305 E longitude and 165-185 N latitude (according to Palestine Grid). It been subjected to exploitation of groundwater from new eleven wells since the 1999 with a total discharge of 11 MCM in addition to the previous discharge rate from the well field 14.7 MCM. Consequently, the aquifer balance is disturbed and a major decline in water level. Therefore, suitable groundwater resources management is required to overcome the problems of over pumping and its effect on groundwater quality. Three–dimensional groundwater flow model Processing Modeflow for Windows Pro (PMWIN PRO, 2003) has been used in order to calculate the groundwater budget, aquifer characteristics, and to predict the aquifer response under different stresses for the next 20 years (2035). The model was calibrated for steady state conditions by trial and error calibration. The calibration was performed by matching observed and calculated initial heads for year 2001. Drawdown data for period 2001-2010 were used to calibrate transient model by matching calculated with observed one, after that, the transient model was validated by using the drawdown data for the period 2011-2014. The hydraulic conductivities of the Basalt- A7/B2 aquifer System are ranging between 1.0 and 8.0 m/day. The low conductivity value was found at the north-west and south-western parts of the study area, the high conductivity value was found at north-western corner of the study area and the average storage coefficient is about 0.025. The water balance for the Basalt and B2/A7 formation at steady state condition with a discrepancy of 0.003%. The major inflows come from Jebal Al Arab through the basalt and through the limestone aquifer (B2/A7 12.28 MCMY aquifer and from excess rainfall is about 0.68 MCM/a. While the major outflows from the Basalt-B2/A7 aquifer system are toward Azraq basin with about 5.03 MCMY and leakage to A1/6 aquitard with 7.89 MCMY. Four scenarios have been performed to predict aquifer system responses under different conditions. Scenario no.2 was found to be the best one which indicates that the reduction the abstraction rates by 50% of current withdrawal rate (25.08 MCMY) to 12.54 MCMY. The maximum drawdowns were decreased to reach about, 7.67 and 8.38m in the years 2025 and 2035 respectively.

Keywords: Amman/Zarqa Basin, Jordan, groundwater management, groundwater modeling, modflow

Procedia PDF Downloads 218
15369 Outbreak of Cholera, Jalgaon District, Maharastra, 2013

Authors: Yogita Tulsian, A. Yadav

Abstract:

Background: India reports 3,600 cholera cases annually. In August 2013, a cholera outbreak was reported in Jalgaon district, Maharashtra state. We sought to describe the epidemiological characteristics,identify risk factors, and recommend control measures. Methods: We collected existing stool and water testing laboratory results, and conducted a1: 1 matched case-control study. A cholera case was defined as a resident of Vishnapur or Malapur villagewith onset of acute watery diarrhea on/ after 1-July-2013. Controls were matched by age, gender and village and had not experienced any diarrhea for 3 months. We collected socio-demographic characteristics, clinical presentation, and food/travel/water exposure history and conducted conditional logistic regression. Results: Of 50 people who met the cholera case definition, 40 (80%) were from Vishnapur village and 30 (60%) were female. The median age was 8.5 years (range; 0.3-75). Twenty (45%) cases were hospitalized, twelve (60%) with severe dehydration. Three of five stool samples revealed Vibrio cholerae 01 El Tor, Ogawa and samples from 7 of 14 Vishnapur water sources contained fecal coliforms. Cases from Vishnapur were significantly more likely to drink from identified contaminated water sources (matched odds ratio (MOR) 3.5; 95% confidence interval (CI): 1-13), or from a river/canal (MOR=18.4;95%CI: 2-504). Cases from Malapur were more likely to drink from a river/canal (MOR=6.2; 95%CI: 0.6-196). Cases from both villages were significantly more likely to visit the forest (MOR 6.3; 95%CI: 2-30) or another village (MOR 3.5; 95%CI; 0.9-17). Conclusions: This outbreak was caused by Vibrio cholerae, likely through contamination of water in Vishnapur village and/or through drinking river/canal water. We recommended safe drinking water for forest visitors and all residents of these villages and use of regular water testing.

Keywords: cholera, case control study, contaminated water, river

Procedia PDF Downloads 362
15368 Effect of Volcanic Ash and Recycled Aggregates in Concrete

Authors: Viviana Letelier, Ester Tarela, Giacomo Moriconi

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The cement industry is responsible for around a 5% of the CO2 emissions worldwide and considering that concrete is one of the most used materials in construction its total effect is important. An alternative to reduce the environmental impact of concrete production is to incorporate certain amount of residuals in the dosing, limiting the replacement percentages to avoid significant losses in the mechanical properties of the final material. This study analyses the variation in the mechanical properties of structural concretes with recycled aggregates and volcanic ash as cement replacement to test the effect of the simultaneous use of different residuals in the same material. Analyzed concretes are dosed for a compressive strength of 30MPa. The recycled aggregates are obtained from prefabricated pipe debris with a compressive strength of 20MPa. The volcanic ash was obtained from the Ensenada (Chile) area after the Calbuco eruption in April 2015. The percentages of natural course aggregates that are replaced by recycled aggregates are of 0% and 30% and the percentages of cement replaced by volcanic ash are of 0%, 5%, 10% and 15%. The combined effect of both residuals in the mechanical properties of the concrete is evaluated through compressive strength tests after, 28 curing days, flexural strength tests after 28 days, and the elasticity modulus after 28 curing days. Results show that increasing the amount of volcanic ash used increases the losses in compressive strength. However, the use of up to a 5% of volcanic ash allows obtaining concretes with similar compressive strength to the control concrete, whether recycled aggregates are used or not. Furthermore, the pozzolanic reaction that occurs between the amorphous silica and the calcium hydroxide (Ca(OH)2) provokes an increase of a 10% in the compressive strength when a 5% of volcanic ash is combined with a 30% of recycled aggregates. Flexural strength does not show significant changes with neither of the residues. On the other hand, decreases between a 14% and a 25% in the elasticity modulus have been found. Concretes with up to a 30% of recycled aggregates and a 5% of volcanic ash as cement replacement can be produced without significant losses in their mechanical properties, reducing considerably the environmental impact of the final material.

Keywords: compressive strength of recycled concrete, mechanical properties of recycled concrete, recycled aggregates, volcanic ash as cement replacement

Procedia PDF Downloads 304