Search results for: externality cost
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5941

Search results for: externality cost

4591 Hybrid Renewable Power Systems

Authors: Salman Al-Alyani

Abstract:

In line with the Kingdom’s Vision 2030, the Saudi Green initiative was announced aimed at reducing carbon emissions by more than 4% of the global contribution. The initiative included plans to generate 50% of its energy from renewables by 2030. The geographical location of Saudi Arabia makes it among the best countries in terms of solar irradiation and has good wind resources in many areas across the Kingdom. Saudi Arabia is a wide country and has many remote locations where it is not economically feasible to connect those loads to the national grid. With the improvement of battery innovation and reduction in cost, different renewable technologies (primarily wind and solar) can be integrated to meet the need for energy in a more effective and cost-effective way. Saudi Arabia is famous for high solar irradiations in which solar power generation can extend up to six (6) hours per day (25% capacity factor) in some locations. However, the net present value (NPV) falls down to negative in some locations due to distance and high installation costs. Wind generation in Saudi Arabia is a promising technology. Hybrid renewable generation will increase the net present value and lower the payback time due to additional energy generated by wind. The infrastructure of the power system can be capitalized to contain solar generation and wind generation feeding the inverter, controller, and load. Storage systems can be added to support the hours that have an absence of wind or solar energy. Also, the smart controller that can help integrate various renewable technologies primarily wind and solar, to meet demand considering load characteristics. It could be scalable for grid or off-grid applications. The objective of this paper is to study the feasibility of introducing a hybrid renewable system in remote locations and the concept for the development of a smart controller.

Keywords: battery storage systems, hybrid power generation, solar energy, wind energy

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4590 Larger Diameter 22 MM-PDC Cutter Greatly Improves Drilling Efficiency of PDC Bit

Authors: Fangyuan Shao, Wei Liu, Deli Gao

Abstract:

With the increasing speed of oil and gas exploration, development and production at home and abroad, the demand for drilling speed up technology is becoming more and more critical to reduce the development cost. Highly efficient and personalized PDC bit is important equipment in the bottom hole assembly (BHA). Therefore, improving the rock-breaking efficiency of PDC bits will help reduce drilling time and drilling cost. Advances in PDC bit technology have resulted in a leapfrogging improvement in the rate of penetration (ROP) of PDC bits over roller cone bits in soft to medium-hard formations. Recently, with the development of PDC technology, the diameter of the PDC tooth can be further expanded. The maximum diameter of the PDC cutter used in this paper is 22 mm. According to the theoretical calculation, under the same depth of cut (DOC), the 22mm-PDC cutter increases the exposure of the cutter, and the increase of PDC cutter diameter helps to increase the cutting area of the PDC cutter. In order to evaluate the cutting performance of the 22 mm-PDC cutter and the existing commonly used cutters, the 16 mm, 19 mm and 22 mm PDC cutter was selected put on a vertical turret lathe (VTL) in the laboratory for cutting tests under different DOCs. The DOCs were 0.5mm, 1.0 mm, 1.5 mm and 2.0 mm, 2.5 mm and 3 mm, respectively. The rock sample used in the experiment was limestone. Results of laboratory tests have shown the new 22 mm-PDC cutter technology greatly improved cutting efficiency. On the one hand, as the DOC increases, the mechanical specific energy (MSE) of all cutters decreases, which means that the cutting efficiency increases. On the other hand, under the same DOC condition, the larger the cutter diameter is, the larger the working area of the cutter is, which leads to higher the cutting efficiency. In view of the high performance of the 22 mm-PDC cutters, which was applied to carry out full-scale bit field experiments. The result shows that the bit with 22mm-PDC cutters achieves a breakthrough improvement of ROP than that with conventional 16mm and 19mm cutters in offset well drilling.

Keywords: polycrystalline diamond compact, 22 mm-PDC cutters, cutting efficiency, mechanical specific energy

Procedia PDF Downloads 186
4589 Additive Weibull Model Using Warranty Claim and Finite Element Analysis Fatigue Analysis

Authors: Kanchan Mondal, Dasharath Koulage, Dattatray Manerikar, Asmita Ghate

Abstract:

This paper presents an additive reliability model using warranty data and Finite Element Analysis (FEA) data. Warranty data for any product gives insight to its underlying issues. This is often used by Reliability Engineers to build prediction model to forecast failure rate of parts. But there is one major limitation in using warranty data for prediction. Warranty periods constitute only a small fraction of total lifetime of a product, most of the time it covers only the infant mortality and useful life zone of a bathtub curve. Predicting with warranty data alone in these cases is not generally provide results with desired accuracy. Failure rate of a mechanical part is driven by random issues initially and wear-out or usage related issues at later stages of the lifetime. For better predictability of failure rate, one need to explore the failure rate behavior at wear out zone of a bathtub curve. Due to cost and time constraints, it is not always possible to test samples till failure, but FEA-Fatigue analysis can provide the failure rate behavior of a part much beyond warranty period in a quicker time and at lesser cost. In this work, the authors proposed an Additive Weibull Model, which make use of both warranty and FEA fatigue analysis data for predicting failure rates. It involves modeling of two data sets of a part, one with existing warranty claims and other with fatigue life data. Hazard rate base Weibull estimation has been used for the modeling the warranty data whereas S-N curved based Weibull parameter estimation is used for FEA data. Two separate Weibull models’ parameters are estimated and combined to form the proposed Additive Weibull Model for prediction.

Keywords: bathtub curve, fatigue, FEA, reliability, warranty, Weibull

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4588 Urgent Care Centres in the United Kingdom

Authors: Mohammad Ansari, Satinder Mann, Ahmed Ismail

Abstract:

Primary care patients in Emergency Departments (ED) have been the topic of discussion since 1998 in the United Kingdom. Numerous studies have analysed attendances in EDs retrospectively and suggest that at least one third to fifty percent patients attending ED with problems which could be managed appropriately in General Practice or minor injuries units. The pattern of ED Usage seems to be International. In Australia and many departments in the United States include walk in facilities staffed by physicians on family practice residency programme. It clearly appears in the United Kingdom that EDs have to accept that such patients with primary care problems will attend the ED and facilities will have to be provided to see and treat such patients. Urgent care centres were introduced in the United Kingdom nearly a decade ago to reduce the pressure on EDs. Most of these were situated near pre-existing EDs. Unfortunately these centres failed to have the desired effect of reducing the number of patients visiting EDs, it has been noticed that when more patients were seen in Urgent Care centres there were increased attendances in ED as well. A new model of Urgent Care centre was started in the ED of George Eliot Hospital, Nuneaton, UK. We looked at the working of the centre by looking at the number of patients seen daily against the number of total attendances in the ED. We studied the number and type of patients seen by the Urgent Care Doctor. All the medical records of the patients were seen and the time patients spent in the Urgent Care centre was recorded. The total number of patients seen during this study were 1532. 219 (14.3% ) were seen within our Urgent Care centre. None of the patients waited over four hours to be seen. It has been recognised that primary care patients in the ED are a major part of attendances of the department and unless these patients are seen in Urgent Care centres, overcrowding and long waits cannot been avoided. It has been shown that employing primary care Physicians in Urgent Care centres reduces overall cost because they do not carry out as many investigations as Junior Doctors. In our study over 14% patients were seen by Urgent Care Physicians and none of the patients waited for more than four hours and we feel that care provided to the patients by Urgent Care centre was highly effective and satisfying for the patient.

Keywords: urgent care centres, primary care physicians, overcrowding, cost

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4587 Experimental Evaluation of Electrocoagulation for Hardness Removal of Bore Well Water

Authors: Pooja Kumbhare

Abstract:

Water is an important resource for the survival of life. The inadequate availability of surface water makes people depend on ground water for fulfilling their needs. However, ground water is generally too hard to satisfy the requirements for domestic as well as industrial applications. Removal of hardness involves various techniques such as lime soda process, ion exchange, reverse osmosis, nano-filtration, distillation, and, evaporation, etc. These techniques have individual problems such as high annual operating cost, sediment formation on membrane, sludge disposal problem, etc. Electrocoagulation (EC) is being explored as modern and cost-effective technology to cope up with the growing demand of high water quality at the consumer end. In general, earlier studies on electrocoagulation for hardness removal are found to deploy batch processes. As batch processes are always inappropriate to deal with large volume of water to be treated, it is essential to develop continuous flow EC process. So, in the present study, an attempt is made to investigate continuous flow EC process for decreasing excessive hardness of bore-well water. The experimental study has been conducted using 12 aluminum electrodes (25cm*10cm, 1cm thick) provided in EC reactor with volume of 8 L. Bore well water sample, collected from a local bore-well (i.e. at – Vishrambag, Sangli; Maharashtra) having average initial hardness of 680 mg/l (Range: 650 – 700 mg/l), was used for the study. Continuous flow electrocoagulation experiments were carried out by varying operating parameters specifically reaction time (Range: 10 – 60 min), voltage (Range: 5 – 20 V), current (Range: 1 – 5A). Based on the experimental study, it is found that hardness removal to the desired extent could be achieved even for continuous flow EC reactor, so the use of it is found promising.

Keywords: hardness, continuous flow EC process, aluminum electrode, optimal operating parameters

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4586 Feasibility of Solar Distillation as Household Water Supply in Saline Zones of Bangladesh

Authors: Md. Rezaul Karim, Md. Ashikur Rahman, Dewan Mahmud Mim

Abstract:

Scarcity of potable water as the result of rapid climate change and saltwater intrusion in groundwater has been a major problem in the coastal regions over the world. In equinoctial countries like Bangladesh, where sunlight is available for more than 10 hours a day, Solar Distillation provides a promising sustainable way for safe drinking water supply in coastal poor households with negligible major cost and difficulty of construction and maintenance. In this paper, two passive type solar stills- a Conventional Single Slope Solar still (CSS) and a Pyramid Solar Sill (PSS) is used and relationship is established between distill water output corresponding to four different factors- temperature, solar intensity, relative humidity and wind speed for Gazipur, Bangladesh. Comparison is analyzed between the two different still outputs for nine months period (January- September) and efficiency is calculated. Later a thermal mathematical model is developed and the distilled water output for Khulna, Bangladesh is computed. Again, difference between the output of the two cities- Gazipur and Khulna is demonstrated and finally an economic analysis is prepared. The distillation output has a positive correlation with temperature and solar intensity, inverse relation with relative humidity and wind speed has nugatory consequence. The maximum output of Conventional Solar Still is obtained 3.8 L/m2/day and Pyramid still is 4.3 L/m2/day for Gazipur and almost 15% more efficiency is found for Pyramid still. Productivity in Khulna is found almost 20% more than Gazipur. Based on economic analysis, taking 10 BDT, per liter, the net profit, benefit cost ratio, payback period all indicates that both stills are feasible but pyramid still is more feasible than Conventional Still. Finally, for a 3-4 member family, area of 4 m2 is suggested for Conventional Still and 3m2 for Pyramid Solar Still.

Keywords: solar distillation, household water supply, saline zones, Bangladesh

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4585 Simulation of Bird Strike on Airplane Wings by Using SPH Methodology

Authors: Tuğçe Kiper Elibol, İbrahim Uslan, Mehmet Ali Guler, Murat Buyuk, Uğur Yolum

Abstract:

According to the FAA report, 142603 bird strikes were reported for a period of 24 years, between 1990 – 2013. Bird strike with aerospace structures not only threaten the flight security but also cause financial loss and puts life in danger. The statistics show that most of the bird strikes are happening with the nose and the leading edge of the wings. Also, a substantial amount of bird strikes is absorbed by the jet engines and causes damage on blades and engine body. Crash proof designs are required to overcome the possibility of catastrophic failure of the airplane. Using computational methods for bird strike analysis during the product development phase has considerable importance in terms of cost saving. Clearly, using simulation techniques to reduce the number of reference tests can dramatically affect the total cost of an aircraft, where for bird strike often full-scale tests are considered. Therefore, development of validated numerical models is required that can replace preliminary tests and accelerate the design cycle. In this study, to verify the simulation parameters for a bird strike analysis, several different numerical options are studied for an impact case against a primitive structure. Then, a representative bird mode is generated with the verified parameters and collided against the leading edge of a training aircraft wing, where each structural member of the wing was explicitly modeled. A nonlinear explicit dynamics finite element code, LS-DYNA was used for the bird impact simulations. SPH methodology was used to model the behavior of the bird. Dynamic behavior of the wing superstructure was observed and will be used for further design optimization purposes.

Keywords: bird impact, bird strike, finite element modeling, smoothed particle hydrodynamics

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4584 Water Management Scheme: Panacea to Development Using Nigeria’s University of Ibadan Water Supply Scheme as a Case Study

Authors: Sunday Olufemi Adesogan

Abstract:

The supply of potable water at least is a very important index in national development. Water tariffs depend on the treatment cost which carries the highest percentage of the total operation cost in any water supply scheme. In order to keep water tariffs as low as possible, treatment costs have to be minimized. The University of Ibadan, Nigeria, water supply scheme consists of a treatment plant with three distribution stations (Amina way, Kurumi and Lander) and two raw water supply sources (Awba dam and Eleyele dam). An operational study of the scheme was carried out to ascertain the efficiency of the supply of potable water on the campus to justify the need for water supply schemes in tertiary institutions. The study involved regular collection, processing and analysis of periodic operational data. Data collected include supply reading (water production on daily basis) and consumers metered reading for a period of 22 months (October 2013 - July 2015), and also collected, were the operating hours of both plants and human beings. Applying the required mathematical equations, total loss was determined for the distribution system, which was translated into monetary terms. Adequacies of the operational functions were also determined. The study revealed that water supply scheme is justified in tertiary institutions. It was also found that approximately 10.7 million Nigerian naira (N) is lost to leakages during the 22-month study period; the system’s storage capacity is no longer adequate, especially for peak water production. The capacity of the system as a whole is insufficient for the present university population and that the existing water supply system is not being operated in an optimal manner especially due to personnel, power and system ageing constraints.

Keywords: development, panacea, supply, water

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4583 Some Issues with Extension of an HPC Cluster

Authors: Pil Seong Park

Abstract:

Homemade HPC clusters are widely used in many small labs, because they are easy to build and cost-effective. Even though incremental growth is an advantage of clusters, it results in heterogeneous systems anyhow. Instead of adding new nodes to the cluster, we can extend clusters to include some other Internet servers working independently on the same LAN, so that we can make use of their idle times, especially during the night. However extension across a firewall raises some security problems with NFS. In this paper, we propose a method to solve such a problem using SSH tunneling, and suggest a modified structure of the cluster that implements it.

Keywords: extension of HPC clusters, security, NFS, SSH tunneling

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4582 Sensing of Cancer DNA Using Resonance Frequency

Authors: Sungsoo Na, Chanho Park

Abstract:

Lung cancer is one of the most common severe diseases driving to the death of a human. Lung cancer can be divided into two cases of small-cell lung cancer (SCLC) and non-SCLC (NSCLC), and about 80% of lung cancers belong to the case of NSCLC. From several studies, the correlation between epidermal growth factor receptor (EGFR) and NSCLCs has been investigated. Therefore, EGFR inhibitor drugs such as gefitinib and erlotinib have been used as lung cancer treatments. However, the treatments result showed low response (10~20%) in clinical trials due to EGFR mutations that cause the drug resistance. Patients with resistance to EGFR inhibitor drugs usually are positive to KRAS mutation. Therefore, assessment of EGFR and KRAS mutation is essential for target therapies of NSCLC patient. In order to overcome the limitation of conventional therapies, overall EGFR and KRAS mutations have to be monitored. In this work, the only detection of EGFR will be presented. A variety of techniques has been presented for the detection of EGFR mutations. The standard detection method of EGFR mutation in ctDNA relies on real-time polymerase chain reaction (PCR). Real-time PCR method provides high sensitive detection performance. However, as the amplification step increases cost effect and complexity increase as well. Other types of technology such as BEAMing, next generation sequencing (NGS), an electrochemical sensor and silicon nanowire field-effect transistor have been presented. However, those technologies have limitations of low sensitivity, high cost and complexity of data analyzation. In this report, we propose a label-free and high-sensitive detection method of lung cancer using quartz crystal microbalance based platform. The proposed platform is able to sense lung cancer mutant DNA with a limit of detection of 1nM.

Keywords: cancer DNA, resonance frequency, quartz crystal microbalance, lung cancer

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4581 Effect of Modification and Expansion on Emergence of Cooperation in Demographic Multi-Level Donor-Recipient Game

Authors: Tsuneyuki Namekata, Yoko Namekata

Abstract:

It is known that the mean investment evolves from a very low initial value to some high level in the Continuous Prisoner's Dilemma. We examine how the cooperation level evolves from a low initial level to a high level in our Demographic Multi-level Donor-Recipient situation. In the Multi-level Donor-Recipient game, one player is selected as a Donor and the other as a Recipient randomly. The Donor has multiple cooperative moves and one defective move. A cooperative move means the Donor pays some cost for the Recipient to receive some benefit. The more cooperative move the Donor takes, the higher cost the Donor pays and the higher benefit the Recipient receives. The defective move has no effect on them. Two consecutive Multi-level Donor-Recipient games, one as a Donor and the other as a Recipient, can be viewed as a discrete version of the Continuous Prisoner's Dilemma. In the Demographic Multi-level Donor-Recipient game, players are initially distributed spatially. In each period, players play multiple Multi-level Donor-Recipient games against other players. He leaves offspring if possible and dies because of negative accumulated payoff of him or his lifespan. Cooperative moves are necessary for the survival of the whole population. There is only a low level of cooperative move besides the defective move initially available in strategies of players. A player may modify and expand his strategy by his recent experiences or practices. We distinguish several types of a player about modification and expansion. We show, by Agent-Based Simulation, that introducing only the modification increases the emergence rate of cooperation and introducing both the modification and the expansion further increases it and a high level of cooperation does emerge in our Demographic Multi-level Donor-Recipient Game.

Keywords: agent-based simulation, donor-recipient game, emergence of cooperation, spatial structure, TFT, TF2T

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4580 QSAR Modeling of Germination Activity of a Series of 5-(4-Substituent-Phenoxy)-3-Methylfuran-2(5H)-One Derivatives with Potential of Strigolactone Mimics toward Striga hermonthica

Authors: Strahinja Kovačević, Sanja Podunavac-Kuzmanović, Lidija Jevrić, Cristina Prandi, Piermichele Kobauri

Abstract:

The present study is based on molecular modeling of a series of twelve 5-(4-substituent-phenoxy)-3-methylfuran-2(5H)-one derivatives which have potential of strigolactones mimics toward Striga hermonthica. The first step of the analysis included the calculation of molecular descriptors which numerically describe the structures of the analyzed compounds. The descriptors ALOGP (lipophilicity), AClogS (water solubility) and BBB (blood-brain barrier penetration), served as the input variables in multiple linear regression (MLR) modeling of germination activity toward S. hermonthica. Two MLR models were obtained. The first MLR model contains ALOGP and AClogS descriptors, while the second one is based on these two descriptors plus BBB descriptor. Despite the braking Topliss-Costello rule in the second MLR model, it has much better statistical and cross-validation characteristics than the first one. The ALOGP and AClogS descriptors are often very suitable predictors of the biological activity of many compounds. They are very important descriptors of the biological behavior and availability of a compound in any biological system (i.e. the ability to pass through the cell membranes). BBB descriptor defines the ability of a molecule to pass through the blood-brain barrier. Besides the lipophilicity of a compound, this descriptor carries the information of the molecular bulkiness (its value strongly depends on molecular bulkiness). According to the obtained results of MLR modeling, these three descriptors are considered as very good predictors of germination activity of the analyzed compounds toward S. hermonthica seeds. This article is based upon work from COST Action (FA1206), supported by COST (European Cooperation in Science and Technology).

Keywords: chemometrics, germination activity, molecular modeling, QSAR analysis, strigolactones

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4579 Evaluation and Analysis of ZigBee-Based Wireless Sensor Network: Home Monitoring as Case Study

Authors: Omojokun G. Aju, Adedayo O. Sule

Abstract:

ZigBee wireless sensor and control network is one of the most popularly deployed wireless technologies in recent years. This is because ZigBee is an open standard lightweight, low-cost, low-speed, low-power protocol that allows true operability between systems. It is built on existing IEEE 802.15.4 protocol and therefore combines the IEEE 802.15.4 features and newly added features to meet required functionalities thereby finding applications in wide variety of wireless networked systems. ZigBee‘s current focus is on embedded applications of general-purpose, inexpensive, self-organising networks which requires low to medium data rates, high number of nodes and very low power consumption such as home/industrial automation, embedded sensing, medical data collection, smart lighting, safety and security sensor networks, and monitoring systems. Although the ZigBee design specification includes security features to protect data communication confidentiality and integrity, however, when simplicity and low-cost are the goals, security is normally traded-off. A lot of researches have been carried out on ZigBee technology in which emphasis has mainly been placed on ZigBee network performance characteristics such as energy efficiency, throughput, robustness, packet delay and delivery ratio in different scenarios and applications. This paper investigate and analyse the data accuracy, network implementation difficulties and security challenges of ZigBee network applications in star-based and mesh-based topologies with emphases on its home monitoring application using the ZigBee ProBee ZE-10 development boards for the network setup. The paper also expose some factors that need to be considered when designing ZigBee network applications and suggest ways in which ZigBee network can be designed to provide more resilient to network attacks.

Keywords: home monitoring, IEEE 802.14.5, topology, wireless security, wireless sensor network (WSN), ZigBee

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4578 Solving LWE by Pregressive Pumps and Its Optimization

Authors: Leizhang Wang, Baocang Wang

Abstract:

General Sieve Kernel (G6K) is considered as currently the fastest algorithm for the shortest vector problem (SVP) and record holder of open SVP challenge. We study the lattice basis quality improvement effects of the Workout proposed in G6K, which is composed of a series of pumps to solve SVP. Firstly, we use a low-dimensional pump output basis to propose a predictor to predict the quality of high-dimensional Pumps output basis. Both theoretical analysis and experimental tests are performed to illustrate that it is more computationally expensive to solve the LWE problems by using a G6K default SVP solving strategy (Workout) than these lattice reduction algorithms (e.g. BKZ 2.0, Progressive BKZ, Pump, and Jump BKZ) with sieving as their SVP oracle. Secondly, the default Workout in G6K is optimized to achieve a stronger reduction and lower computational cost. Thirdly, we combine the optimized Workout and the Pump output basis quality predictor to further reduce the computational cost by optimizing LWE instances selection strategy. In fact, we can solve the TU LWE challenge (n = 65, q = 4225, = 0:005) 13.6 times faster than the G6K default Workout. Fourthly, we consider a combined two-stage (Preprocessing by BKZ- and a big Pump) LWE solving strategy. Both stages use dimension for free technology to give new theoretical security estimations of several LWE-based cryptographic schemes. The security estimations show that the securities of these schemes with the conservative Newhope’s core-SVP model are somewhat overestimated. In addition, in the case of LAC scheme, LWE instances selection strategy can be optimized to further improve the LWE-solving efficiency even by 15% and 57%. Finally, some experiments are implemented to examine the effects of our strategies on the Normal Form LWE problems, and the results demonstrate that the combined strategy is four times faster than that of Newhope.

Keywords: LWE, G6K, pump estimator, LWE instances selection strategy, dimension for free

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4577 Using ANN in Emergency Reconstruction Projects Post Disaster

Authors: Rasha Waheeb, Bjorn Andersen, Rafa Shakir

Abstract:

Purpose The purpose of this study is to avoid delays that occur in emergency reconstruction projects especially in post disaster circumstances whether if they were natural or manmade due to their particular national and humanitarian importance. We presented a theoretical and practical concepts for projects management in the field of construction industry that deal with a range of global and local trails. This study aimed to identify the factors of effective delay in construction projects in Iraq that affect the time and the specific quality cost, and find the best solutions to address delays and solve the problem by setting parameters to restore balance in this study. 30 projects were selected in different areas of construction were selected as a sample for this study. Design/methodology/approach This study discusses the reconstruction strategies and delay in time and cost caused by different delay factors in some selected projects in Iraq (Baghdad as a case study).A case study approach was adopted, with thirty construction projects selected from the Baghdad region, of different types and sizes. Project participants from the case projects provided data about the projects through a data collection instrument distributed through a survey. Mixed approach and methods were applied in this study. Mathematical data analysis was used to construct models to predict delay in time and cost of projects before they started. The artificial neural networks analysis was selected as a mathematical approach. These models were mainly to help decision makers in construction project to find solutions to these delays before they cause any inefficiency in the project being implemented and to strike the obstacles thoroughly to develop this industry in Iraq. This approach was practiced using the data collected through survey and questionnaire data collection as information form. Findings The most important delay factors identified leading to schedule overruns were contractor failure, redesigning of designs/plans and change orders, security issues, selection of low-price bids, weather factors, and owner failures. Some of these are quite in line with findings from similar studies in other countries/regions, but some are unique to the Iraqi project sample, such as security issues and low-price bid selection. Originality/value we selected ANN’s analysis first because ANN’s was rarely used in project management , and never been used in Iraq to finding solutions for problems in construction industry. Also, this methodology can be used in complicated problems when there is no interpretation or solution for a problem. In some cases statistical analysis was conducted and in some cases the problem is not following a linear equation or there was a weak correlation, thus we suggested using the ANN’s because it is used for nonlinear problems to find the relationship between input and output data and that was really supportive.

Keywords: construction projects, delay factors, emergency reconstruction, innovation ANN, post disasters, project management

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4576 Review on the Role of Sustainability Techniques in Development of Green Building

Authors: Ubaid Ur Rahman, Waqar Younas, Sooraj Kumar Chhabira

Abstract:

Environmentally sustainable building construction has experienced significant growth during the past 10 years at international level. This paper shows that the conceptual framework adopts sustainability techniques in construction to develop environment friendly building called green building. Waste occurs during the different construction phases which causes the environmental problems like, deposition of waste on ground surface creates major problems such as bad smell. It also gives birth to different health diseases and produces toxic waste agent which is specifically responsible for making soil infertile. Old recycled building material is used in the construction of new building. Sustainable construction is economical and saves energy sources. Sustainable construction is the major responsibility of designer and project manager. The designer has to fulfil the client demands while keeping the design environment friendly. Project manager has to deliver and execute sustainable construction according to sustainable design. Steel is the most appropriate sustainable construction material. It is more durable and easily recyclable. Steel occupies less area and has more tensile and compressive strength than concrete, making it a better option for sustainable construction as compared to other building materials. New technology like green roof has made the environment pleasant, and has reduced the construction cost. It minimizes economic, social and environmental issues. This paper presents an overview of research related to the material use of green building and by using this research recommendation are made which can be followed in the construction industry. In this paper, we go through detailed analysis on construction material. By making suitable adjustments to project management practices it is shown that a green building improves the cost efficiency of the project, makes it environmental friendly and also meets future generation demands.

Keywords: sustainable construction, green building, recycled waste material, environment

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4575 Pre-Cooling Strategies for the Refueling of Hydrogen Cylinders in Vehicular Transport

Authors: C. Hall, J. Ramos, V. Ramasamy

Abstract:

Hydrocarbon-based fuel vehicles are a major contributor to air pollution due to harmful emissions produced, leading to a demand for cleaner fuel types. A leader in this pursuit is hydrogen, with its application in vehicles producing zero harmful emissions and the only by-product being water. To compete with the performance of conventional vehicles, hydrogen gas must be stored on-board of vehicles in cylinders at high pressures (35–70 MPa) and have a short refueling duration (approximately 3 mins). However, the fast-filling of hydrogen cylinders causes a significant rise in temperature due to the combination of the negative Joule-Thompson effect and the compression of the gas. This can lead to structural failure and therefore, a maximum allowable internal temperature of 85°C has been imposed by the International Standards Organization. The technological solution to tackle the issue of rapid temperature rise during the refueling process is to decrease the temperature of the gas entering the cylinder. Pre-cooling of the gas uses a heat exchanger and requires energy for its operation. Thus, it is imperative to determine the least amount of energy input that is required to lower the gas temperature for cost savings. A validated universal thermodynamic model is used to identify an energy-efficient pre-cooling strategy. The model requires negligible computational time and is applied to previously validated experimental cases to optimize pre-cooling requirements. The pre-cooling characteristics include the location within the refueling timeline and its duration. A constant pressure-ramp rate is imposed to eliminate the effects of rapid changes in mass flow rate. A pre-cooled gas temperature of -40°C is applied, which is the lowest allowable temperature. The heat exchanger is assumed to be ideal with no energy losses. The refueling of the cylinders is modeled with the pre-cooling split in ten percent time intervals. Furthermore, varying burst durations are applied in both the early and late stages of the refueling procedure. The model shows that pre-cooling in the later stages of the refuelling process is more energy-efficient than early pre-cooling. In addition, the efficiency of pre-cooling towards the end of the refueling process is independent of the pressure profile at the inlet. This leads to the hypothesis that pre-cooled gas should be applied as late as possible in the refueling timeline and at very low temperatures. The model had shown a 31% reduction in energy demand whilst achieving the same final gas temperature for a refueling scenario when pre-cooling was applied towards the end of the process. The identification of the most energy-efficient refueling approaches whilst adhering to the safety guidelines is imperative to reducing the operating cost of hydrogen refueling stations. Heat exchangers are energy-intensive and thus, reducing the energy requirement would lead to cost reduction. This investigation shows that pre-cooling should be applied as late as possible and for short durations.

Keywords: cylinder, hydrogen, pre-cooling, refueling, thermodynamic model

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4574 An Investigation on the Need to Provide Environmental Sanitation Facilities to Informal Settlement in Shagari Low-Cost Katsina State for Sustainable Built Environment

Authors: Abdullahi Mannir Rawayau

Abstract:

This paper identifies the problems that have aided the decoy to adequate basic infrastructural amenities, sub-standard housing, over-crowding, poor ventilation in homes and work places, sanitation, and non-compliance with building bye-laws and regulation. The paper also asserts the efficient disposal of solid and liquid waste is one of the challenges in the informal areas due to threats on the environment and public health. Sanitation services in the informal settlements have been found to be much lower compared to the average for unban. Bearing in mind a factor which prevents sustainable sanitation in informal areas which include low incomes, insecure tenure, low education levels, difficulty topography and transitory populations, and this study aim to identify effective strategies for achieving sustainable sanitation with specific reference to the informal settlement. Using the Shanghai Low-Cost as a case study. The primary data collected was through observation and interview method. Similarly, the secondary data used for the study was collected through literature reviews from extent studies with specific reference to informal settlement. A number of strategies towards achieving sustainable sanitation in the study were identified here in classified into three (3):- Advocacy and capacity building, infrastructural provision and institutionalization of systems and processes. The paper concludes with the premise on the need to build alliances between the government and stakeholders concerned with sanitation provision through the creation of sanitation and employ adaptable technology. Provision of sanitation facilities in public areas and to establish a statutory body for timely response to sanitation waste management in Katsina. It is imperative to check and prevent further decay for harmonious living and sustainable development.

Keywords: built environment, sanitation, facilities, settlement

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4573 Disadvantages and Drawbacks of Concrete Blocks and Fix Their Defects

Authors: Ehsan Sadie

Abstract:

Today, the cost of repair and maintenance of structures is very important and by studying the behavior of reinforced concrete structures Will become specified several factors such as : Design and calculation errors, lack of proper implementation of structural changes, the damage caused by the introduction of random loads, concrete corrosion and environmental conditions reduce durability of the structures . Meanwhile building codes alteration also cause changes in the assessment and review of the design and structure rather if necessary will be improved and strengthened in the future.

Keywords: concrete building , expandable cement, honeycombed surface , reinforcement corrosion

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4572 A Comparative Study of the Use of Medicinal Plants and Conventional Medicine for the Treatment of Hepatitis B Virus in Ibadan Metropolis

Authors: Julius Adebayo John

Abstract:

The objective of this study is to compare the use of medicinal plants and Conventional medicine intervention in the management of HBV among Ibadan populace. A purposive sampling technique was used to administer questionnaires at 2 places, namely, the University College Hospital and Total Healthcare Diagnostic Centre, Ibadan, where viral loads are carried out. A EuroQol (EQ – 5D) was adopted to collect data. Descriptive and inferential analyses were performed. Also, ANOVA, Correlation, charts, and tables were used. Findings revealed a high prevalence of HBV among female respondents and sample between ages 26years to 50years. Results showed that the majority discovered their health status through free HBV tests. Analysis indicated that the use of medicinal plant extract is cost-effective in 73% of cases. Rank order utility derived from medicinal plants is higher than other interventions. Correlation analysis performed for the current health status of respondents were significant at P<0.01 against the intervention management adopted (0.046), cost of treatment (0.549), utility (0.407) at P<0.00, duration of the treatment (0.604) at P<0.01; viral load before treatment (-0.142) not significant at P<0.01, the R2 (72.2%) showed the statistical variance in respondents current health status as explained by the independent variables. Respondents gained quality-adjusted life-years (QALYs) of between 1year to 3years. Suggestions were made for a public-private partnership effort against HBV with emphasis on periodic screening, viral load test subsidy, and free vaccination of people with –HBV status. Promoting phytomedicine through intensive research with strong regulation of herbal practitioners will go a long way in alleviating the burdens of the disease in society.

Keywords: medicinal plant, HBV management interventions, utility, QALYs, ibadan metropolis

Procedia PDF Downloads 142
4571 Enhancing Warehousing Operation In Cold Supply Chain Through The Use Of IOT And Lifi Technologies

Authors: Sarah El-Gamal, Passent Hossam, Ahmed Abd El Aziz, Rojina Mahmoud, Ahmed Hassan, Dalia Hilal, Eman Ayman, Hana Haytham, Omar Khamis

Abstract:

Several concerns fall upon the supply chain, especially the cold supply chain. According to the literature, the main challenges in the cold supply chain are the distribution and storage phases. In this research, researchers focused on the storage area, which contains several activities such as the picking activity that faces a lot of obstacles and challenges The implementation of IoT solutions enables businesses to monitor the temperature of food items, which is perhaps the most critical parameter in cold chains. Therefore, researchers proposed a practical solution that would help in eliminating the problems related to ineffective picking for products, especially fish and seafood products, by using IoT technology, most notably LiFi technology. Thus, guaranteeing sufficient picking, reducing waste, and consequently lowering costs. A prototype was specially designed and examined. This research is a single case study research. Two methods of data collection were used; observation and semi-structured interviews. Semi-structured interviews were conducted with managers and decision maker at Carrefour Alexandria to validate the problem and the proposed practical solution using IoTandLiFi technology. A total of three interviews were conducted. As a result, a SWOT analysis was achieved in order to highlight all the strengths and weaknesses of using the recommended Lifi solution in the picking process. According to the investigations, it was found that the use of IoT and LiFi technology is cost effective, efficient, and reduces human errors, minimize the percentage of product waste and thus save money and cost. Thus, increasing customer satisfaction and profits gained.

Keywords: cold supply chain, picking process, temperature control, IOT, warehousing, LIFI

Procedia PDF Downloads 169
4570 Next-Generation Laser-Based Transponder and 3D Switch for Free Space Optics in Nanosatellite

Authors: Nadir Atayev, Mehman Hasanov

Abstract:

Future spacecraft will require a structural change in the way data is transmitted due to the increase in the volume of data required for space communication. Current radio frequency communication systems are already facing a bottleneck in the volume of data sent to the ground segment due to their technological and regulatory characteristics. To overcome these issues, free space optics communication plays an important role in the integrated terrestrial space network due to its advantages such as significantly improved data rate compared to traditional RF technology, low cost, improved security, and inter-satellite free space communication, as well as uses a laser beam, which is an optical signal carrier to establish satellite-ground & ground-to-satellite links. In this approach, there is a need for high-speed and energy-efficient systems as a base platform for sending high-volume video & audio data. Nano Satellite and its branch CubeSat platforms have more technical functionality than large satellites, wheres cover an important part of the space sector, with their Low-Earth-Orbit application area with low-cost design and technical functionality for building networks using different communication topologies. Along the research theme developed in this regard, the output parameter indicators for the FSO of the optical communication transceiver subsystem on the existing CubeSat platforms, and in the direction of improving the mentioned parameters of this communication methodology, 3D optical switch and laser beam controlled optical transponder with 2U CubeSat structural subsystems and application in the Low Earth Orbit satellite network topology, as well as its functional performance and structural parameters, has been studied accordingly.

Keywords: cubesat, free space optics, nano satellite, optical laser communication.

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4569 Analysis of Two-Echelon Supply Chain with Perishable Items under Stochastic Demand

Authors: Saeed Poormoaied

Abstract:

Perishability and developing an intelligent control policy for perishable items are the major concerns of marketing managers in a supply chain. In this study, we address a two-echelon supply chain problem for perishable items with a single vendor and a single buyer. The buyer adopts an aged-based continuous review policy which works by taking both the stock level and the aging process of items into account. The vendor works under the warehouse framework, where its lot size is determined with respect to the batch size of the buyer. The model holds for a positive and fixed lead time for the buyer, and zero lead time for the vendor. The demand follows a Poisson process and any unmet demand is lost. We provide exact analytic expressions for the operational characteristics of the system by using the renewal reward theorem. Items have a fixed lifetime after which they become unusable and are disposed of from the buyer's system. The age of items starts when they are unpacked and ready for the consumption at the buyer. When items are held by the vendor, there is no aging process which results in no perishing at the vendor's site. The model is developed under the centralized framework, which takes the expected profit of both vendor and buyer into consideration. The goal is to determine the optimal policy parameters under the service level constraint at the retailer's site. A sensitivity analysis is performed to investigate the effect of the key input parameters on the expected profit and order quantity in the supply chain. The efficiency of the proposed age-based policy is also evaluated through a numerical study. Our results show that when the unit perishing cost is negligible, a significant cost saving is achieved.

Keywords: two-echelon supply chain, perishable items, age-based policy, renewal reward theorem

Procedia PDF Downloads 130
4568 Optimisation Model for Maximising Social Sustainability in Construction Scheduling

Authors: Laura Florez

Abstract:

The construction industry is labour intensive, and the behaviour and management of workers have a direct impact on the performance of construction projects. One of the issues it currently faces is how to recruit and maintain its workers. Construction is known as an industry where workers face the problem of short employment durations, frequent layoffs, and periods of unemployment between jobs. These challenges not only creates pressures on the workers but also project managers have to constantly train new workers, face skills shortage, and uncertainty on the quality of the workers it will attract. To consider worker’s needs and project managers expectations, one practice that can be implemented is to schedule construction projects to maintain a stable workforce. This paper proposes a mixed integer programming (MIP) model to schedule projects with the objective of maximising social sustainability of construction projects, that is, maximise labour stability. Aside from the social objective, the model accounts for equipment and financial resources required by the projects during the construction phase. To illustrate how the solution strategy works, a construction programme comprised of ten projects is considered. The projects are scheduled to maximise labour stability while simultaneously minimising time and minimising cost. The tradeoff between the values in terms of time, cost, and labour stability allows project managers to consider their preferences and identify which solution best suits their needs. Additionally, the model determines the optimal starting times for each of the projects, working patterns for the workers, and labour costs. This model shows that construction projects can be scheduled to not only benefit the project manager, but also benefit current workers and help attract new workers to the industry. Due to its practicality, it can be a valuable tool to support decision making and assist construction stakeholders when developing schedules that include social sustainability factors.

Keywords: labour stability, mixed-integer programming (MIP), scheduling, workforce management

Procedia PDF Downloads 244
4567 Leveraging Information for Building Supply Chain Competitiveness

Authors: Deepika Joshi

Abstract:

Operations in automotive industry rely greatly on information shared between Supply Chain (SC) partners. This leads to efficient and effective management of SC activity. Automotive sector in India is growing at 14.2 percent per annum and has huge economic importance. We find that no study has been carried out on the role of information sharing in SC management of Indian automotive manufacturers. Considering this research gap, the present study is planned to establish the significance of information sharing in Indian auto-component supply chain activity. An empirical research was conducted for large scale auto component manufacturers from India. Twenty four Supply Chain Performance Indicators (SCPIs) were collected from existing literature. These elements belong to eight diverse but internally related areas of SC management viz., demand management, cost, technology, delivery, quality, flexibility, buyer-supplier relationship, and operational factors. A pair-wise comparison and an open ended questionnaire were designed using these twenty four SCPIs. The questionnaire was then administered among managerial level employees of twenty-five auto-component manufacturing firms. Analytic Network Process (ANP) technique was used to analyze the response of pair-wise questionnaire. Finally, twenty-five priority indexes are developed, one for each respondent. These were averaged to generate an industry specific priority index. The open-ended questions depicted strategies related to information sharing between buyers and suppliers and their influence on supply chain performance. Results show that the impact of information sharing on certain performance indicators is relatively greater than their corresponding variables. For example, flexibility, delivery, demand and cost related elements have massive impact on information sharing. Technology is relatively less influenced by information sharing but it immensely influence the quality of information shared. Responses obtained from managers reveal that timely and accurate information sharing lowers the cost, increases flexibility and on-time delivery of auto parts, therefore, enhancing the competitiveness of Indian automotive industry. Any flaw in dissemination of information can disturb the cycle time of both the parties and thus increases the opportunity cost. Due to supplier’s involvement in decisions related to design of auto parts, quality conformance is found to improve, leading to reduction in rejection rate. Similarly, mutual commitment to share right information at right time between all levels of SC enhances trust level. SC partners share information to perform comprehensive quality planning to ingrain total quality management. This study contributes to operations management literature which faces scarcity of empirical examination on this subject. It views information sharing as a building block which firms can promote and evolve to leverage the operational capability of all SC members. It will provide insights for Indian managers and researchers as every market is unique and suppliers and buyers are driven by local laws, industry status and future vision. While major emphasis in this paper is given to SC operations happening between domestic partners, placing more focus on international SC can bring in distinguished results.

Keywords: Indian auto component industry, information sharing, operations management, supply chain performance indicators

Procedia PDF Downloads 536
4566 Response of Grower Turkeys to Diets Containing Moringa oleifera Leaf Meal in a Tropical Environment

Authors: Augustine O. Ani, Ifeyinwa E. Ezemagu, Eunice A. Akuru

Abstract:

A seven-week study was conducted to evaluate the response of grower turkeys to varying dietary levels of Moringa oleifera leaf meal (MOLM) in a humid tropical environment. A total of 90 twelve weeks old male and female grower turkeys were randomly divided into five groups of 18 birds each in a completely randomized design (CRD) and assigned to five caloric (2.57-2.60 Mcal/kg ME) and isonitrogenous (19.95% crude protein) diets containing five levels (0, 15, 20, 25 and 30%) of MOLM, respectively. Each treatment was replicated three times with 6 birds per replicate housed in a deep litter pen of fresh wood shavings measuring 1.50m x 1.50m. Feed and water were provided to the birds' ad libitum. Parameters measured were: final live weight (FLW) daily weight gain (DWG), daily feed intake (DFI), feed conversion ratio (FCR), protein efficiency ratio (PER), packed cell volume (PCV), haemoglobin concentration (Hb), red blood cell (RBC) count, white blood cell (WBC) count, mean cell volume (MCV), mean cell haemoglobin (MCH) and mean cell haemoglobin concentration (MCHC), feed cost / kg weight gain and apparent nutrient retention. Results showed that grower turkeys fed 20% MOLM diet had significantly (p < 0.05) higher FLW and DWG values (4410.30 g and 34.49 g, respectively) and higher DM and NFE retention values (67.28 and 58.12%, respectively) than turkeys fed other MOLM diets. Feed cost per kg gain decreased significantly (p < 0.05) with increasing levels of MOLM in the diets. The PCV, Hb, WBC, MCV, MCH and MCHC values of grower turkeys fed 20% MOLM diet were significantly (p < 0.05) higher than those of grower turkeys fed other diets. It was concluded that a diet containing 20% MOLM is adequate for the normal growth of grower turkeys in the tropics.

Keywords: Diets, grower turkeys, Moringa oleifera leaf meal, response, tropical environment

Procedia PDF Downloads 130
4565 Multiple-Material Flow Control in Construction Supply Chain with External Storage Site

Authors: Fatmah Almathkour

Abstract:

Managing and controlling the construction supply chain (CSC) are very important components of effective construction project execution. The goals of managing the CSC are to reduce uncertainty and optimize the performance of a construction project by improving efficiency and reducing project costs. The heart of much SC activity is addressing risk, and the CSC is no different. The delivery and consumption of construction materials is highly variable due to the complexity of construction operations, rapidly changing demand for certain components, lead time variability from suppliers, transportation time variability, and disruptions at the job site. Current notions of managing and controlling CSC, involve focusing on one project at a time with a push-based material ordering system based on the initial construction schedule and, then, holding a tremendous amount of inventory. A two-stage methodology was proposed to coordinate the feed-forward control of advanced order placement with a supplier to a feedback local control in the form of adding the ability to transship materials between projects to improve efficiency and reduce costs. It focused on the single supplier integrated production and transshipment problem with multiple products. The methodology is used as a design tool for the CSC because it includes an external storage site not associated with one of the projects. The idea is to add this feature to a highly constrained environment to explore its effectiveness in buffering the impact of variability and maintaining project schedule at low cost. The methodology uses deterministic optimization models with objectives that minimizing the total cost of the CSC. To illustrate how this methodology can be used in practice and the types of information that can be gleaned, it is tested on a number of cases based on the real example of multiple construction projects in Kuwait.

Keywords: construction supply chain, inventory control supply chain, transshipment

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4564 Saving Energy through Scalable Architecture

Authors: John Lamb, Robert Epstein, Vasundhara L. Bhupathi, Sanjeev Kumar Marimekala

Abstract:

In this paper, we focus on the importance of scalable architecture for data centers and buildings in general to help an enterprise achieve environmental sustainability. The scalable architecture helps in many ways, such as adaptability to the business and user requirements, promotes high availability and disaster recovery solutions that are cost effective and low maintenance. The scalable architecture also plays a vital role in three core areas of sustainability: economy, environment, and social, which are also known as the 3 pillars of a sustainability model. If the architecture is scalable, it has many advantages. A few examples are that scalable architecture helps businesses and industries to adapt to changing technology, drive innovation, promote platform independence, and build resilience against natural disasters. Most importantly, having a scalable architecture helps industries bring in cost-effective measures for energy consumption, reduce wastage, increase productivity, and enable a robust environment. It also helps in the reduction of carbon emissions with advanced monitoring and metering capabilities. Scalable architectures help in reducing waste by optimizing the designs to utilize materials efficiently, minimize resources, decrease carbon footprints by using low-impact materials that are environmentally friendly. In this paper we also emphasize the importance of cultural shift towards the reuse and recycling of natural resources for a balanced ecosystem and maintain a circular economy. Also, since all of us are involved in the use of computers, much of the scalable architecture we have studied is related to data centers.

Keywords: scalable architectures, sustainability, application design, disruptive technology, machine learning and natural language processing, AI, social media platform, cloud computing, advanced networking and storage devices, advanced monitoring and metering infrastructure, climate change

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4563 Modeling Socioeconomic and Political Dynamics of Terrorism in Pakistan

Authors: Syed Toqueer, Omer Younus

Abstract:

Terrorism, today, has emerged as a global menace with Pakistan being the most adversely affected state. Therefore, the motive behind this study is to empirically establish the linkage of terrorism with socio-economic (uneven income distribution, poverty and unemployment) and political nexuses so that a policy recommendation can be put forth to better approach this issue in Pakistan. For this purpose, the study employs two competing models, namely, the distributed lag model and OLS, so that findings of the model may be consolidated comprehensively, over the reference period of 1984-2012. The findings of both models are indicative of the fact that uneven income distribution of Pakistan is rather a contributing factor towards terrorism when measured through GDP per capita. This supports the hypothesis that immiserizing modernization theory is applicable for the state of Pakistan where the underprivileged are marginalized. Results also suggest that other socio-economic variables (poverty, unemployment and consumer confidence) can condense the brutality of terrorism once these conditions are catered to and improved. The rational of opportunity cost is at the base of this argument. Poor conditions of employment and poverty reduces the opportunity cost for individuals to be recruited by terrorist organizations as economic returns are considerably low and thus increasing the supply of volunteers and subsequently increasing the intensity of terrorism. The argument of political freedom as a means of lowering terrorism stands true. The more the people are politically repressed the more alternative and illegal means they will find to make their voice heard. Also, the argument that politically transitioning economy faces more terrorism is found applicable for Pakistan. Finally, the study contributes to an ongoing debate on which of the two set of factors are more significant with relation to terrorism by suggesting that socio-economic factors are found to be the primary causes of terrorism for Pakistan.

Keywords: terrorism, socioeconomic conditions, political freedom, distributed lag model, ordinary least square

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4562 An Investigation of the Effects of Gripping Systems in Geosynthetic Shear Testing

Authors: Charles Sikwanda

Abstract:

The use of geosynthetic materials in geotechnical engineering projects has rapidly increased over the past several years. These materials have resulted in improved performance and cost reduction of geotechnical structures as compared to the use of conventional materials. However, working with geosynthetics requires knowledge of interface parameters for design. These parameters are typically determined by the large direct shear device in accordance with ASTM-D5321 and ASTM-D6243 standards. Although these laboratory tests are standardized, the quality of the results can be largely affected by several factors that include; the shearing rate, applied normal stress, gripping mechanism, and type of the geosynthetic specimens tested. Amongst these factors, poor surface gripping of a specimen is the major source of the discrepancy. If the specimen is inadequately secured to the shearing blocks, it experiences progressive failure and shear strength that deviates from the true field performance of the tested material. This leads to inaccurate, unsafe, and cost ineffective designs of projects. Currently, the ASTM-D5321 and ASTM-D6243 standards do not provide a standardized gripping system for geosynthetic shear strength testing. Over the years, researchers have come up with different gripping systems that can be used such as; glue, metal textured surface, sandblasting, and sandpaper. However, these gripping systems are regularly not adequate to sufficiently secure the tested specimens to the shearing device. This has led to large variability in test results and difficulties in results interpretation. Therefore, this study was aimed at determining the effects of gripping systems in geosynthetic interface shear strength testing using a 300 x 300 mm direct shear box. The results of the research will contribute to easy data interpretation and increase result accuracy and reproducibility.

Keywords: geosynthetics, shear strength parameters, gripping systems, gripping

Procedia PDF Downloads 192