Search results for: effective use
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 9244

Search results for: effective use

4354 Tranexamic Acid in Orthopedic Surgery in Children

Authors: K. Amanzoui, A. Erragh, M. Elharit, A. Afif, K. Elfakhr, S. Kalouch, A. Chlilek

Abstract:

Orthopedic surgery is a provider of pre and postoperative bleeding; patients are exposed to several risks, and different measures are proposed to reduce bleeding during surgery, called the transfusion-sparing method, including tranexamic acid, which has shown its effectiveness in numerous studies. A prospective analytical study in 50 children was carried out in the orthopedic traumatology operating room of the EL HAROUCHI hospital of the CHU IBN ROCHD in Casablanca over a period of six months (April to October 2022). Two groups were randomized: one receiving tranexamic acid (Group A) and a non-receiving control group (Group B). The average age was 10.3 years, of which 58.8% were female. The first type of surgery was thoracolumbar scoliosis (52%). The average preoperative hemoglobin was 12.28 g/dl in group A, against 12.67 g/dl in the control group. There was no significant difference between the two groups (p=0.148). Mean intraoperative bleeding was 396.29 ml in group A versus 412 ml in the control group. No significant difference was observed for this parameter (p=0.632). The average hemoglobin level in the immediate postoperative period in our patients is 10.2 g/dl. In group A, it was 10.95 g/dl versus 10.93 g/dl in group B. At H24 postoperative, the mean hemoglobin value was 10.29 g/dl in group A against 9.5 g/dl in group B. For group A, the blood loss recorded during the first 24 hours was 209.43 ml, against 372 ml in group B, with a significant difference between the two groups (p=0.001). There is no statistically significant difference between the 2 groups in terms of the use of fillers, ephedrine or intraoperative transfusion. While for postoperative transfusion, we note the existence of a statistically significant difference between group A and group B. It is suggested that the use of tranexamic acid is an effective, simple, and low-cost way to limit postoperative blood loss and the need for transfusion.

Keywords: tranexamic acid, blood loss, orthopedic surgery, children

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4353 A Survey of Feature-Based Steganalysis for JPEG Images

Authors: Syeda Mainaaz Unnisa, Deepa Suresh

Abstract:

Due to the increase in usage of public domain channels, such as the internet, and communication technology, there is a concern about the protection of intellectual property and security threats. This interest has led to growth in researching and implementing techniques for information hiding. Steganography is the art and science of hiding information in a private manner such that its existence cannot be recognized. Communication using steganographic techniques makes not only the secret message but also the presence of hidden communication, invisible. Steganalysis is the art of detecting the presence of this hidden communication. Parallel to steganography, steganalysis is also gaining prominence, since the detection of hidden messages can prevent catastrophic security incidents from occurring. Steganalysis can also be incredibly helpful in identifying and revealing holes with the current steganographic techniques, which makes them vulnerable to attacks. Through the formulation of new effective steganalysis methods, further research to improve the resistance of tested steganography techniques can be developed. Feature-based steganalysis method for JPEG images calculates the features of an image using the L1 norm of the difference between a stego image and the calibrated version of the image. This calibration can help retrieve some of the parameters of the cover image, revealing the variations between the cover and stego image and enabling a more accurate detection. Applying this method to various steganographic schemes, experimental results were compared and evaluated to derive conclusions and principles for more protected JPEG steganography.

Keywords: cover image, feature-based steganalysis, information hiding, steganalysis, steganography

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4352 The Implementation of Anti-Circumvention Legislations in Thai Copyright System

Authors: Chuencheewin Yimfuang

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The WIPO copyright treaty (WCT) was established by the World Intellectual Property Organisation (WIPO). This agreement required the contracting nations to provide adequate protection to technological measures to prevent massive copyright infringement in the internet system. Thailand had to implement the anti-circumvention rules into domestic legislation to comply with this international obligation. The purpose of this paper is to critically discuss the legislative standard under the WCT. It also aims to examine the legal development of technological protection measures in Thailand and demonstrate that the scope of prohibitions under the copyright Act 2022 (NO.5) is similar to the Digital Millennium Copyright Act 1998 (DMCA) of the United States (US). It could be found that the anti-circumvention laws of Thailand prohibit the circumvention of access-control technologies, and the regulation on trafficking circumvention devices has been added to the latest version of the Thai Copyright Act. These legislative evolutions have revealed the attempt to reinforce the legal protection of technological measures and copyright holders in order to be in line with global practices. However, the amendment has problems concerning the legal definitions of effective technological measure and the prohibited act of circumvention. The vagueness might affect the scope of protection and the boundary of prohibition. With this aspect, the DMCA will be evaluated and compared to gain guidelines for interpretation and enforcement in Thailand. The lessons and experiences learned from this study might be useful to correct the flaws or at least clarify the ambiguities embodied in Thai copyright legislation.

Keywords: legal development, technological protection measure, circumvention, Thailand

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4351 Flood Disaster Prevention and Mitigation in Nigeria Using Geographic Information System

Authors: Dinebari Akpee, Friday Aabe Gaage, Florence Fred Nwaigwu

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Natural disasters like flood affect many parts of the world including developing countries like Nigeria. As a result, many human lives are lost, properties damaged and so much money is lost in infrastructure damages. These hazards and losses can be mitigated and reduced by providing reliable spatial information to the generality of the people through about flood risks through flood inundation maps. Flood inundation maps are very crucial for emergency action plans, urban planning, ecological studies and insurance rates. Nigeria experience her worst flood in her entire history this year. Many cities were submerged and completely under water due to torrential rainfall. Poor city planning, lack of effective development control among others contributes to the problem too. Geographic information system (GIS) can be used to visualize the extent of flooding, analyze flood maps to produce flood damaged estimation maps and flood risk maps. In this research, the under listed steps were taken in preparation of flood risk maps for the study area: (1) Digitization of topographic data and preparation of digital elevation model using ArcGIS (2) Flood simulation using hydraulic model and integration and (3) Integration of the first two steps to produce flood risk maps. The results shows that GIS can play crucial role in Flood disaster control and mitigation.

Keywords: flood disaster, risk maps, geographic information system, hazards

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4350 Hierarchical Optimization of Composite Deployable Bridge Treadway Using Particle Swarm Optimization

Authors: Ashraf Osman

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Effective deployable bridges that are characterized by an increased capacity to weight ratio are recently needed for post-disaster rapid mobility and military operations. In deployable bridging, replacing metals as the fabricating material with advanced composite laminates as lighter alternatives with higher strength is highly advantageous. This article presents a hierarchical optimization strategy of a composite bridge treadway considering maximum strength design and bridge weight minimization. Shape optimization of a generic deployable bridge beam cross-section is performed to achieve better stress distribution over the bridge treadway hull. The developed cross-section weight is minimized up to reserving the margins of safety of the deployable bridging code provisions. Hence, the strength of composite bridge plates is maximized through varying the plies orientation. Different loading cases are considered of a tracked vehicle patch load. The orthotropic plate properties of a composite sandwich core are used to simulate the bridge deck structural behavior. Whereas, the failure analysis is conducted using Tsai-Wu failure criterion. The naturally inspired particle swarm optimization technique is used in this study. The proposed technique efficiently reduced the weight to capacity ratio of the developed bridge beam.

Keywords: CFRP deployable bridges, disaster relief, military bridging, optimization of composites, particle swarm optimization

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4349 Finite Element Analysis and Design Optimization of Stent and Balloon System

Authors: V. Hashim, P. N. Dileep

Abstract:

Stent implantation is being seen as the most successful method to treat coronary artery diseases. Different types of stents are available in the market these days and the success of a stent implantation greatly depends on the proper selection of a suitable stent for a patient. Computer numerical simulation is the cost effective way to choose the compatible stent. Studies confirm that the design characteristics of stent do have great importance with regards to the pressure it can sustain, the maximum displacement it can produce, the developed stress concentration and so on. In this paper different designs of stent were analyzed together with balloon to optimize the stent and balloon system. Commercially available stent Palmaz-Schatz has been selected for analysis. Abaqus software is used to simulate the system. This work is the finite element analysis of the artery stent implant to find out the design factors affecting the stress and strain. The work consists of two phases. In the first phase, stress distribution of three models were compared - stent without balloon, stent with balloon of equal length and stent with balloon of extra length than stent. In second phase, three different design models of Palmaz-Schatz stent were compared by keeping the balloon length constant. The results obtained from analysis shows that, the design of the strut have strong effect on the stress distribution. A design with chamfered slots found better results. The length of the balloon also has influence on stress concentration of the stent. Increase in length of the balloon will reduce stress, but will increase dog boning effect.

Keywords: coronary stent, finite element analysis, restenosis, stress concentration

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4348 The Study of Thai Consumer Behavior toward Buying Goods on the Internet

Authors: Pichamon Chansuchai

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The study of Thai consumer behavior toward buying goods on the Internet is a survey research. The five-level rating scale and open-ended questionnaire are applied for this research procedure, which has more than 400 random sampling of Thai people aged between 15-40 years old. The summary findings are: The analysis of respondents profile were female 55.3% and male 44.8% , 35.3% aged between 20-30 years old, had been employed 29.5% with average income up to 11,000 baht/month 50.2% and expenditure more than 11,000 baht per month 29.3%. The internet usage behavior of respondents mostly found that objectives of the internet usage are: 1) Communication 93.3% 2) the categories of websites usage was trading 42.8% 3) The marketing mix effected to trading behavior via internet which can be analyzed in term of marketing factor as following: Product focused on product quality was the most influenced factor with average value 4.75. The cheaper price than overview market was the most effect factor to internet shopping with mean value 4.53. The average value 4.67 of the available place that could reduce spending time for shopping. The effective promotion of the buy 1 get 1 was the stimulus factor for internet shopping with mean value 4.60. For hypothesis testing, the different sex has relationship with buying decision. It presented that male and female have vary purchasing decision via internet with value of significant difference 0.05. Furthermore, the variety occupations of respondents related to the use of selected type of website. It also found that the vary of personal occupation effected to the type of website selection dissimilar with value of significant difference 0.05.

Keywords: behavior, internet, consumer, goods

Procedia PDF Downloads 233
4347 Theoretical Model of a Flat Plate Solar Collector Integrated with Phase Change Material

Authors: Mouna Hamed, Ammar B. Brahim

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The objective of this work was to develop a theoretical model to study the dynamic thermal behavior of a flat plate solar collector integrated with a phase change material (PCM). The PCM acted as a heat source for the solar system during low intensity solar radiation and night. The energy balance equations for the various components of the collector as well as for the PCM were formulated and numerically solved using MATLAB computational program. The effect of natural convection on heat during the melting process was taken into account by using an effective thermal conductivity. The model was used to investigate the effect of inlet water temperature, water mass flow rate, and PCM thickness on the outlet water temperature and the melt fraction during charging and discharging modes. A comparison with a collector without PCM was made. Results showed that charging and discharging processes of PCM have six stages. The adding of PCM caused a decrease in temperature during charge and an increase during discharge. The rise was most enhanced for higher inlet water temperature, PCM thickness and for lower mass flow rate. Analysis indicated that the complete melting time was shorter than the solidification time due to the high heat transfer coefficient during melting. The increases in PCM height and mass flow rate were not linear with the melting and solidification times.

Keywords: thermal energy storage, phase change material, melting, solidification

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4346 Evaluation of Zooplankton Community and Saprobi Index of Carps Culture Ponds: Case Study on East of Golestan Province-Gonbade Kavous City

Authors: Mehrdad Kamali-Sanzighi, Maziar Kamali-Sanzighi

Abstract:

The aim of this research was to study zooplankton community density, diversity and Saprobi index in carp ponds at Golestan province, Gonbade Kavous city, Iran. Zooplankton sampling was done monthly in each pond during one carp culture time. Our analysis showed 27 genus from 4 groups (Protozoa 12, Rotatoria 8, Copepoda 4 and Cladocera 3). The highest and lowest frequency of zooplankton groups were belongs to Rotatoria, Copepoda, Cladocera and Protozoa with 46, 28, 23 and 3 percent, respectively. No significant differences between saprobi index of six carp ponds (P>0.05) were observed. Saprobi index indicated Class ßmesosaprob for six analysis ponds. There was a general tendency to decrease and significantly in the saprobi index with the value range of 1.52-1.70 from the beginning to end of the culture season (P<0.05). Also, gradual improvement of water quality observed toward the end of culture period and these reasons are partly a result of natural and management processed such as seasons changes (climate), water exchange (replacement of water) and pause of introduce of fertilizer materials to the ponds. According to the ability of saprobi index in monitoring of water quality condition and health of different water resources, focus to similar kind of effective research is necessary in future time.

Keywords: zooplankton, saprobi pollution index, water quality, fish pond, east of Golestan Province

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4345 Mitigating Acid Mine Drainage Pollution: A Case Study In the Witwatersrand Area of South Africa

Authors: Elkington Sibusiso Mnguni

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In South Africa, mining has been a key economic sector since the discovery of gold in 1886 in the Witwatersrand region, where the city of Johannesburg is located. However, some mines have since been decommissioned, and the continuous pumping of acid mine drainage (AMD) also stopped causing the AMD to rise towards the ground surface. This posed a serious environmental risk to the groundwater resources and river systems in the region. This paper documents the development and extent of the environmental damage as well as the measures implemented by the government to alleviate such damage. The study will add to the body of knowledge on the subject of AMD treatment to prevent environmental degradation. The method used to gather and collate relevant data and information was the desktop study. The key findings include the social and environmental impact of the AMD, which include the pollution of water sources for domestic use leading to skin and other health problems and the loss of biodiversity in some areas. It was also found that the technical intervention of constructing a plant to pump and treat the AMD using the high-density sludge technology was the most effective short-term solution available while a long-term solution was being explored. Some successes and challenges experienced during the implementation of the project are also highlighted. The study will be a useful record of the current status of the AMD treatment interventions in the region.

Keywords: acid mine drainage, groundwater resources, pollution, river systems, technical intervention, high density sludge

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4344 An Analysis of Present Supplier Selection Criteria of State Pharmaceutical Corporation (SPC) Sri Lanka: A Case Study

Authors: Gamalath M. B. P. Abeysekara

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Primary objective of any organization is to enhance the bottom line profit. Strategic procurement is one of the prominent aspects in view of receiving this ultimate objective. Strategic procurement is an activity used in each and every organization in their operations. Pharmaceutical procurement is an especially significant task for any organizations, particularly state sector concerned. The whole pharmaceutical procurement requirement of the country is procured through the State Pharmaceutical Corporation (SPC) of Sri Lanka. They follow Pharmaceutical Procurement Guideline of 2006 as the procurement principle. The main objective of this project is to identify the importance of State Pharmaceutical Corporation supplier selection criteria and critical analysis of pharmaceutical procurement procedure. State Pharmaceutical Corporations applied net price, product quality, past performance, and delivery of suppliers’ as main criteria for the selection suppliers. Data collection for this study was taken place through a questionnaire, given to fifty doctors within the Colombo district attached to five main state hospitals. Data analysis is carried out with mean and standard deviation functions. The ultimate outcomes indicated product quality, net price, and delivery of suppliers’ are the most important criteria behind the selection of suppliers. Critical analysis proved State Pharmaceutical Corporation should focus on net price reduction, improving laboratory testing facilities and effective communication between up and down stream of supply chain.

Keywords: government procurement procedure, pharmaceutical procurement supplier selection criteria, importance of SPC supplier selection criteria

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4343 Reducing Component Stress during Encapsulation of Electronics: A Simulative Examination of Thermoplastic Foam Injection Molding

Authors: Constantin Ott, Dietmar Drummer

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The direct encapsulation of electronic components is an effective way of protecting components against external influences. In addition to achieving a sufficient protective effect, there are two other big challenges for satisfying the increasing demand for encapsulated circuit boards. The encapsulation process should be both suitable for mass production and offer a low component load. Injection molding is a method with good suitability for large series production but also with typically high component stress. In this article, two aims were pursued: first, the development of a calculation model that allows an estimation of the occurring forces based on process variables and material parameters. Second, the evaluation of a new approach for stress reduction by means of thermoplastic foam injection molding. For this purpose, simulation-based process data was generated with the Moldflow simulation tool. Based on this, component stresses were calculated with the calculation model. At the same time, this paper provided a model for estimating the forces occurring during overmolding and derived a solution method for reducing these forces. The suitability of this approach was clearly demonstrated and a significant reduction in shear forces during overmolding was achieved. It was possible to demonstrate a process development that makes it possible to meet the two main requirements of direct encapsulation in addition to a high protective effect.

Keywords: encapsulation, stress reduction, foam-injection-molding, simulation

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4342 Corrosion Resistance Evaluation of Reinforcing Bars: A Comparative Study of Fusion Bonded Epoxy Coated, Cement Polymer Composite Coated and Dual Zinc Epoxy Coated Rebar for Application in Reinforced Concrete Structures

Authors: Harshit Agrawal, Salman Muhammad

Abstract:

Degradation to reinforced concrete (RC), primarily due to corrosion of embedded reinforcement, has been a major cause of concern worldwide. Among several ways to control corrosion, the use of coated reinforcement has gained significant interest in field applications. However, the choice of proper coating material and the effect of damage over coating are yet to be addressed for effective application of coated reinforcements. The present study aims to investigate and compare the performance of three different types of coated reinforcements —Fusion-Bonded Epoxy Coating (FBEC), Cement Polymer Composite Coating (CPCC), and Dual Zinc-Epoxy Coating (DZEC) —in concrete structures. The aim is to assess their corrosion resistance, durability, and overall effectiveness as coated reinforcement materials both in undamaged and simulated damaged conditions. Through accelerated corrosion tests, electrochemical analysis, and exposure to aggressive marine environments, the study evaluates the long-term performance of each coating system. This research serves as a crucial guide for engineers and construction professionals in selecting the most suitable corrosion protection for reinforced concrete, thereby enhancing the durability and sustainability of infrastructure.

Keywords: corrosion, reinforced concrete, coated reinforcement, seawater exposure, electrochemical analysis, service life, corrosion prevention

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4341 Pilot Scale Sub-Surface Constructed Wetland: Evaluation of Performance of Bed Vegetated with Water Hyacinth in the Treatment of Domestic Sewage

Authors: Abdul-Hakeem Olatunji Abiola, A. E. Adeniran, A. O. Ajimo, A. B. Lamilisa

Abstract:

Introduction: Conventional wastewater treatment technology has been found to fail in developing countries because they are expensive to construct, operate and maintain. Constructed wetlands are nowadays considered as a low-cost alternative for effective wastewater treatment, especially where suitable land can be available. This study aims to evaluate the performance of the constructed wetland vegetated with water hyacinth (Eichhornia crassipes) plant for the treatment of wastewater. Methodology: The sub-surface flow wetland used for this study was an experimental scale constructed wetland consisting of four beds A, B, C, and D. Beds A, B, and D were vegetated while bed C which was used as a control was non-vegetated. This present study presents the results from bed B vegetated with water hyacinth (Eichhornia crassipes) and control bed C which was non-vegetated. The influent of the experimental scale wetland has been pre-treated with sedimentation, screening and anaerobic chamber before feeding into the experimental scale wetland. Results: pH and conductivity level were more reduced, colour of effluent was more improved, nitrate, iron, phosphate, and chromium were more removed, and dissolved oxygen was more improved in the water hyacinth bed than the control bed. While manganese, nickel, cyanuric acid, and copper were more removed from the control bed than the water hyacinth bed. Conclusion: The performance of the experimental scale constructed wetland bed planted with water hyacinth (Eichhornia crassipes) is better than that of the control bed. It is therefore recommended that plain bed without any plant should not be encouraged.

Keywords: constructed experimental scale wetland, domestic sewage, treatment, water hyacinth

Procedia PDF Downloads 119
4340 Rural Tourism Entrepreneurship as Strategy for Economic Development in Nigeria

Authors: Salami Ayobami Taofeek, Ajayi Adeola

Abstract:

Rural tourism entrepreurship is a tourist industry which revolutionizes businesses and prompting economic development across the globe. It encompasses huge range activities, natural or man-made attractions, amenities and facilities, transportation, marketing and information systems. It is also an important export for 83% of the developing countries and the main export for one third of them. In 2000, developing countries recorded 142.6 million international arrivals an increase of 95% compared to the figures of 1990. However, only developing countries with effective natural and man-made tourism supporting and enhancing infrastructure have been able to develop their tourism sector and seize the attendance advantages. Rural areas of Nigeria possess some distinctive peculiarities which can be transformed into attractive tourist centers. In spite of all these, rural tourism areas are still faced with myriad problems which include poor finance inadequate awareness and education, lack of progress in developing the rural of progress in developing the rural tourism potentials inadequate legislation, insecurity, entrepreneurial inertness, over-dependent on oil among others. This paper focuses on the impact and challenges of rural tourism entrepreneurship as strategy for economic development in Nigeria. It reviews literature rural tourism, tourism entrepreneurship potentials and classifications of Nigerians tourism potential’s destinations. The paper concludes that Nigeria Government should encourage rural based tourism entrepreneurship development by addressing the challenges facing rural tourism entrepreneurship in the country.

Keywords: entrepreneurship, economic development, rural tourism, tourism destinations tourism potentials

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4339 Ferulic Acid-Grafted Chitosan: Thermal Stability and Feasibility as an Antioxidant for Active Biodegradable Packaging Film

Authors: Sarekha Woranuch, Rangrong Yoksan

Abstract:

Active packaging has been developed based on the incorporation of certain additives, in particular antimicrobial and antioxidant agents, into packaging systems to maintain or extend product quality and shelf-life. Ferulic acid is one of the most effective natural phenolic antioxidants, which has been used in food, pharmaceutical and active packaging film applications. However, most phenolic compounds are sensitive to oxygen, light and heat; its activities are thus lost during product formulation and processing. Grafting ferulic acid onto polymer is an alternative to reduce its loss under thermal processes. Therefore, the objectives of the present research were to study the thermal stability of ferulic acid after grafting onto chitosan, and to investigate the possibility of using ferulic acid-grafted chitosan (FA-g-CTS) as an antioxidant for active biodegradable packaging film. FA-g-CTS was incorporated into biodegradable film via a two-step process, i.e. compounding extrusion at temperature up to 150 °C followed by blown film extrusion at temperature up to 175 °C. Although incorporating FA-g-CTS with a content of 0.02–0.16% (w/w) caused decreased water vapor barrier property and reduced extensibility, the films showed improved oxygen barrier property and antioxidant activity. Radical scavenging activity and reducing power of the film containing FA-g-CTS with a content of 0.04% (w/w) were higher than that of the naked film about 254% and 94%, respectively. Tensile strength and rigidity of the films were not significantly affected by adding FA-g-CTS with a content of 0.02–0.08% (w/w). The results indicated that FA-g-CTS could be potentially used as an antioxidant for active packaging film.

Keywords: active packaging film, antioxidant activity, chitosan, ferulic acid

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4338 The Virtual Container Yard: Identifying the Persuasive Factors in Container Interchange

Authors: L. Edirisinghe, Zhihong Jin, A. W. Wijeratne, R. Mudunkotuwa

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The virtual container yard is an effective solution to the container inventory imbalance problem which is a global issue. It causes substantial cost to carriers, which inadvertently adds to the prices of consumer goods. The virtual container yard is rooted in the fundamentals of container interchange between carriers. If carriers opt to interchange their excess containers with those who are deficit, a substantial part of the empty reposition cost could be eliminated. Unlike in other types of ships, cargo cannot be directly loaded to a container ship. Slots and containers are supplementary components; thus, without containers, a carrier cannot ship cargo if the containers are not available and vice versa. Few decades ago, carriers recognized slot (the unit of space in a container ship) interchange as a viable solution for the imbalance of shipping space. Carriers interchange slots among them and it also increases the advantage of scale of economies in container shipping. Some of these service agreements between mega carriers have provisions to interchange containers too. However, the interchange mechanism is still not popular among carriers for containers. This is the paradox that prevails in the liner shipping industry. At present, carriers reposition their excess empty containers to areas where they are in demand. This research applied factor analysis statistical method. The paper reveals that five major components may influence the virtual container yard namely organisation, practice and culture, legal and environment, international nature, and marketing. There are 12 variables that may impact the virtual container yard, and these are explained in the paper.

Keywords: virtual container yard, shipping, imbalance, management, inventory

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4337 Thermal Conductivity and Optical Absorption of GaAsPN/GaP for Tandem Solar Cells: Effect of Rapid Thermal Annealing

Authors: S. Ilahi, S. Almosni, F. Chouchene, M. Perrin, K. Zelazna, N. Yacoubi, R. Kudraweic, P. Rale, L. Lombez, J. F. Guillemoles, O. Durand, C. Cornet

Abstract:

Great efforts have been dedicated to obtain high quality of GaAsPN. The properties of GaAsPN have played a great part on the development of solar cells devices based in Si substrate. The incorporation of N in GaAsPN that having a band gap around of 1.7 eV is of special interest in view of growing in Si substrate. In fact, post-growth and rapid thermal annealing (RTA) could be an effective way to improve the quality of the layer. Then, the influence of growth conditions and post-growth annealing on optical and thermal parameters is considered. We have used Photothermal deflection spectroscopy PDS to investigate the impact of rapid thermal annealing on thermal and optical properties of GaAsPN. In fact, the principle of the PDS consists to illuminate the sample by a modulated monochromatic light beam. Then, the absorbed energy is converted into heat through the nonradiative recombination process. The generated thermal wave propagates into the sample and surrounding media creating a refractive-index gradient giving rise to the deflection of a laser probe beam skimming the sample surface. The incident light is assumed to be uniform, and only the sample absorbs the light. In conclusion, the results are promising revealing an improvement in absorption coefficient and thermal conductivity.

Keywords: GaAsPN absorber, photothermal defelction technique PDS, photonics on silicon, thermal conductivity

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4336 Laboratory Scale Experimental Studies on CO₂ Based Underground Coal Gasification in Context of Clean Coal Technology

Authors: Geeta Kumari, Prabu Vairakannu

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Coal is the largest fossil fuel. In India, around 37 % of coal resources found at a depth of more than 300 meters. In India, more than 70% of electricity production depends on coal. Coal on combustion produces greenhouse and pollutant gases such as CO₂, SOₓ, NOₓ, and H₂S etc. Underground coal gasification (UCG) technology is an efficient and an economic in-situ clean coal technology, which converts these unmineable coals into valuable calorific gases. The UCG syngas (mainly H₂, CO, CH₄ and some lighter hydrocarbons) which can utilized for the production of electricity and manufacturing of various useful chemical feedstock. It is an inherent clean coal technology as it avoids ash disposal, mining, transportation and storage problems. Gasification of underground coal using steam as a gasifying medium is not an easy process because sending superheated steam to deep underground coal leads to major transportation difficulties and cost effective. Therefore, for reducing this problem, we have used CO₂ as a gasifying medium, which is a major greenhouse gas. This paper focus laboratory scale underground coal gasification experiment on a coal block by using CO₂ as a gasifying medium. In the present experiment, first, we inject oxygen for combustion for 1 hour and when the temperature of the zones reached to more than 1000 ºC, and then we started supplying of CO₂ as a gasifying medium. The gasification experiment was performed at an atmospheric pressure of CO₂, and it was found that the amount of CO produced due to Boudouard reaction (C+CO₂  2CO) is around 35%. The experiment conducted to almost 5 hours. The maximum gas composition observed, 35% CO, 22 % H₂, and 11% CH4 with LHV 248.1 kJ/mol at CO₂/O₂ ratio 0.4 by volume.

Keywords: underground coal gasification, clean coal technology, calorific value, syngas

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4335 Load-Enabled Deployment and Sensing Range Optimization for Lifetime Enhancement of WSNs

Authors: Krishan P. Sharma, T. P. Sharma

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Wireless sensor nodes are resource constrained battery powered devices usually deployed in hostile and ill-disposed areas to cooperatively monitor physical or environmental conditions. Due to their limited power supply, the major challenge for researchers is to utilize their battery power for enhancing the lifetime of whole network. Communication and sensing are two major sources of energy consumption in sensor networks. In this paper, we propose a deployment strategy for enhancing the average lifetime of a sensor network by effectively utilizing communication and sensing energy to provide full coverage. The proposed scheme is based on the fact that due to heavy relaying load, sensor nodes near to the sink drain energy at much faster rate than other nodes in the network and consequently die much earlier. To cover this imbalance, proposed scheme finds optimal communication and sensing ranges according to effective load at each node and uses a non-uniform deployment strategy where there is a comparatively high density of nodes near to the sink. Probable relaying load factor at particular node is calculated and accordingly optimal communication distance and sensing range for each sensor node is adjusted. Thus, sensor nodes are placed at locations that optimize energy during network operation. Formal mathematical analysis for calculating optimized locations is reported in present work.

Keywords: load factor, network lifetime, non-uniform deployment, sensing range

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4334 Reliability-Centered Maintenance Application for the Development of Maintenance Strategy for a Cement Plant

Authors: Nabil Hameed Al-Farsi

Abstract:

This study’s main goal is to develop a model and a maintenance strategy for a cement factory called Arabian Cement Company, Rabigh Plant. The proposed work here depends on Reliability centric maintenance approach to develop a strategy and maintenance schedule that ensures increasing the reliability of the production system components, thus ensuring continuous productivity. The cost-effective maintenance of the plant’s dependability performance is the key goal of durability-based maintenance is. The cement plant consists of 7 important steps, so, developing a maintenance plan based on Reliability centric maintenance (RCM) method is made up of 10 steps accordingly starting from selecting units and data until performing and updating the model. The processing unit chosen for the analysis of this case is the calcinatory unit regarding model’s validation and the Travancore Titanium Products Ltd (TTP) using the claimed data history acquired from the maintenance department maintenance from the mentioned company. After applying the proposed model, the results of the maintenance simulation justified the plant's existing scheduled maintenance policy being reconsidered. Results represent the need for preventive maintenance for all Class A criticality equipment instead of the planned maintenance and the breakdown one for all other equipment depends on its criticality and an FMEA report. Consequently, the additional cost of preventive maintenance would be offset by the cost savings from breakdown maintenance for the remaining equipment.

Keywords: engineering, reliability, strategy, maintenance, failure modes, effects and criticality analysis (FMEA)

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4333 A Literature Review on Bladder Management in Individuals with Spinal Cord Injury

Authors: Elif Ates, Naile Bilgili

Abstract:

Background: One of the most important medical complications that individuals with spinal cord injury (SCI) face are the neurogenic bladder. Objectives: To review methods used for management of neurogenic bladder and their effects. Methods: The study was conducted by searching CINAHL, Ebscohost, MEDLINE, Science Direct, Ovid, ProQuest, Web of Science, and ULAKBİM National Databases for studies published between 2005 and 2015. Key words used during the search included ‘spinal cord injury’, ‘bladder injury’, ‘nursing care’, ‘catheterization’ and ‘intermittent urinary catheter’. After examination of 551 studies, 21 studies which met inclusion criteria were included in the review. Results: Mean age of individuals in all study samples was 42 years. The most commonly used bladder management method was clean intermittent catheterization (CIC). Compliance with CIC was found to be significantly related to spasticity, maximum cystometric capacity, and the person performing catheterization (p < .05). The main reason for changing the existing bladder management method was urinary tract infections (UTI). Individuals who performed CIC by themselves and who voided spontaneously had better life quality. Patient age, occupation status and whether they performed CIC by themselves or not were found to be significantly associated with depression level (p ≤ .05). Conclusion: As the most commonly used method for bladder management, CIC is a reliable and effective method, and reduces the risk of UTI development. Individuals with neurogenic bladder have a higher prevalence of depression symptoms than the normal population.

Keywords: bladder management, catheterization, nursing, spinal cord injury

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4332 Multi-Temporal Cloud Detection and Removal in Satellite Imagery for Land Resources Investigation

Authors: Feng Yin

Abstract:

Clouds are inevitable contaminants in optical satellite imagery, and prevent the satellite imaging systems from acquiring clear view of the earth surface. The presence of clouds in satellite imagery bring negative influences for remote sensing land resources investigation. As a consequence, detecting the locations of clouds in satellite imagery is an essential preprocessing step, and further remove the existing clouds is crucial for the application of imagery. In this paper, a multi-temporal based satellite imagery cloud detection and removal method is proposed, which will be used for large-scale land resource investigation. The proposed method is mainly composed of four steps. First, cloud masks are generated for cloud contaminated images by single temporal cloud detection based on multiple spectral features. Then, a cloud-free reference image of target areas is synthesized by weighted averaging time-series images in which cloud pixels are ignored. Thirdly, the refined cloud detection results are acquired by multi-temporal analysis based on the reference image. Finally, detected clouds are removed via multi-temporal linear regression. The results of a case application in Hubei province indicate that the proposed multi-temporal cloud detection and removal method is effective and promising for large-scale land resource investigation.

Keywords: cloud detection, cloud remove, multi-temporal imagery, land resources investigation

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4331 Potential of Macroalgae Ulva lactuca for Municipal Wastewater Treatment and Fruitfly Food

Authors: Shuang Qiu, Lingfeng Wang, Zhipeng Chen, Shijian Ge

Abstract:

Macroalgae are considered a promising approach for wastewater treatment as well as an alternative animal feed in addition to a biofuel feedstock. Their large size and/or tendency to grow as dense floating mats or substrate-attached turfs lead to lower separation and drying costs than microalgae. In this study, the macroalgae species Ulva lactuca (U. lactuca) were used to investigate their capacity for treating municipal wastewaters, and the feasibility of using the harvested biomass as an alternative food source for the fruitfly Drosophila melanogaster, an animal model for biological research. Results suggested that U. lactuca could successfully grow on three types of wastewaters studied with biomass productivities of 8.12-64.3 g DW (dry weight)/(m²∙d). The secondary wastewater (SW) was demonstrated as the most effective wastewater medium for U. lactuca growth. However, both high nitrogen (92.5-98.9%) and phosphorus (64.5-88.6%) removal efficiencies were observed in all wastewaters, particularly in primary wastewater (PW) and SW, however, in central wastewater (CW), the highest removal rates were obtained (N 24.7 ± 0.97 and P 0.69 ± 0.01 mg/(g DW·d)). Additionally, the inclusion of 20% washed U. lactuca with 80% standard fruitfly food (w/w) resulted in a longer lifespan and more stable body weights in flies. On the other hand, similar results were not obtained for the food treatment with the addition of 20 % unwashed U. lactuca. This study suggests a promising method for the macroalgae-based treatment of municipal wastewater and the biomass for animal feed.

Keywords: animal feed, flies, macroalgae, nutrient recovery, Ulva lactuca, wastewater

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4330 Influence of Nitrogen Doping on the Catalytic Activity of Ni-Incorporated Carbon Nanofibers for Alkaline Direct Methanol Fuel Cells

Authors: Mohamed H. El-Newehy, Badr M. Thamer, Nasser A. M. Barakat, Mohammad A.Abdelkareem, Salem S. Al-Deyab, Hak Y. Kim

Abstract:

In this study, the influence of nitrogen doping on the electrocatalytic activity of carbon nanofibers with nickel nanoparticles toward methanol oxidation is introduced. The modified carbon nanofibers have been synthesized from calcination of electrospun nanofiber mats composed of nickel acetate tetrahydrate, poly(vinyl alcohol) and urea in argon atmosphere at 750oC. The utilized physicochemical characterizations indicated that the proposed strategy leads to form carbon nanofibers having nickel nanoparticles and doped by nitrogen. Moreover, due to the high-applied voltage during the electrospinning process, the utilized urea chemically bonds with the polymer matrix, which leads to form nitrogen-doped CNFs after the calcination process. Investigation of the electrocatalytic activity indicated that nitrogen doping NiCNFs strongly enhances the oxidation process of methanol as the current density increases from 52.5 to 198.5 mA/cm2 when the urea content in the original electrospun solution was 4 wt% urea. Moreover, the nanofibrous morphology exhibits distinct impact on the electrocatalytic activity. Also, nitrogen-doping enhanced the stability of the introduced Ni-based electrocatalyst. Overall, the present study introduces effective and simple strategy to modify the electrocatalytic activity of the nickel-based materials.

Keywords: electrospinning, methanol electrooxidation, fuel cells, nitrogen-doping, nickel

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4329 Numerical Solution of Space Fractional Order Linear/Nonlinear Reaction-Advection Diffusion Equation Using Jacobi Polynomial

Authors: Shubham Jaiswal

Abstract:

During modelling of many physical problems and engineering processes, fractional calculus plays an important role. Those are greatly described by fractional differential equations (FDEs). So a reliable and efficient technique to solve such types of FDEs is needed. In this article, a numerical solution of a class of fractional differential equations namely space fractional order reaction-advection dispersion equations subject to initial and boundary conditions is derived. In the proposed approach shifted Jacobi polynomials are used to approximate the solutions together with shifted Jacobi operational matrix of fractional order and spectral collocation method. The main advantage of this approach is that it converts such problems in the systems of algebraic equations which are easier to be solved. The proposed approach is effective to solve the linear as well as non-linear FDEs. To show the reliability, validity and high accuracy of proposed approach, the numerical results of some illustrative examples are reported, which are compared with the existing analytical results already reported in the literature. The error analysis for each case exhibited through graphs and tables confirms the exponential convergence rate of the proposed method.

Keywords: space fractional order linear/nonlinear reaction-advection diffusion equation, shifted Jacobi polynomials, operational matrix, collocation method, Caputo derivative

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4328 Development of Industry Oriented Undergraduate Research Program

Authors: Sung Ryong Kim, Hyung Sup Han, Jae-Yup Kim

Abstract:

Many engineering students feel uncomfortable in solving the industry related problems. There are many ways to strengthen the engineering student’s ability to solve the assigned problem when they get a job. Korea National University of Transportation has developed an industry-oriented undergraduate research program (URP). An URP program is designed for engineering students to provide an experience of solving a company’s research problem. The URP project is carried out for 6 months. Each URP team consisted of 1 company mentor, 1 professor, and 3-4 engineering students. A team of different majors is strongly encouraged to integrate different perspectives of multidisciplinary background. The corporate research projects proposed by companies are chosen by the major-related student teams. A company mentor gives the detailed technical background of the project to the students, and he/she also provides a basic data, raw materials and so forth. The company allows students to use the company's research equipment. An assigned professor has adjusted the project scope and level to the student’s ability after discussing with a company mentor. Monthly meeting is used to check the progress, to exchange ideas, and to help the students. It is proven as an effective engineering education program not only to provide an experience of company research but also to motivate the students in their course work. This program provides a premier interdisciplinary platform for undergraduate students to perform the practical challenges encountered in their major-related companies and it is especially helpful for students who want to get a job from a company that proposed the project.

Keywords: company mentor, industry oriented, interdisciplinary platform, undergraduate research program

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4327 The Relation between Learning Styles and English Achievement in the Language Training Centre

Authors: Nurul Yusnita

Abstract:

Many studies have been developed to help the students to get good achievement in English learning. They can be from the teaching method or psychological ones. One of the psychological studies in educational research is learning style. In some ways, learning style can affect the achievement of the students. This study aimed to examine 4 (four) learning styles and their relations to English achievement among the students learning English in Language Training Center of Universitas Muhammadiyah Yogyakarta (LTC UMY). The method of this study was descriptive analytical. The sample consisted of 39 Accounting students in LTC UMY. The data was collected through questionnaires with Likert-scale. The achievement was obtained from the grade of the students. To analyze the questionnaires and to see the relation between the learning styles and the student achievement, SPSS statistical software of correlational analysis was used. The result showed that both visual and auditory had the same percentage of 35.9% (14 students). 3 students (7.7%) had kinaesthetic learning style and 8 students (20.5%) had visual and auditory ones. Meanwhile, there were 5 students (12.8%) who had visual learning style could increase their grades. Only 1 student (2.5%) who had visual and auditory could improve his grade. Besides grade increase, there were also grade decrease. Students with visual, auditory, visual and auditory, and kinaesthetic learning styles were 3 students (7.7%), 5 students (12%), 4 students (10.2%) and 1 student (2.5%) respectively. In conclusion, there was no significant relationship between learning style and English achievement. Most of the good achievers were the students with visual and auditory learning styles and most of them preferred visual method. The implication is the teachers and material designers could improve their method through visual things to achieve effective English teaching learning.

Keywords: accounting students, English achievement, language training centre, learning styles

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4326 Effect Analysis of an Improved Adaptive Speech Noise Reduction Algorithm in Online Communication Scenarios

Authors: Xingxing Peng

Abstract:

With the development of society, there are more and more online communication scenarios such as teleconference and online education. In the process of conference communication, the quality of voice communication is a very important part, and noise may cause the communication effect of participants to be greatly reduced. Therefore, voice noise reduction has an important impact on scenarios such as voice calls. This research focuses on the key technologies of the sound transmission process. The purpose is to maintain the audio quality to the maximum so that the listener can hear clearer and smoother sound. Firstly, to solve the problem that the traditional speech enhancement algorithm is not ideal when dealing with non-stationary noise, an adaptive speech noise reduction algorithm is studied in this paper. Traditional noise estimation methods are mainly used to deal with stationary noise. In this chapter, we study the spectral characteristics of different noise types, especially the characteristics of non-stationary Burst noise, and design a noise estimator module to deal with non-stationary noise. Noise features are extracted from non-speech segments, and the noise estimation module is adjusted in real time according to different noise characteristics. This adaptive algorithm can enhance speech according to different noise characteristics, improve the performance of traditional algorithms to deal with non-stationary noise, so as to achieve better enhancement effect. The experimental results show that the algorithm proposed in this chapter is effective and can better adapt to different types of noise, so as to obtain better speech enhancement effect.

Keywords: speech noise reduction, speech enhancement, self-adaptation, Wiener filter algorithm

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4325 A More Sustainable Decellularized Plant Scaffold for Lab Grown Meat with Ocean Water

Authors: Isabella Jabbour

Abstract:

The world's population is expected to reach over 10 billion by 2050, creating a significant demand for food production, particularly in the agricultural industry. Cellular agriculture presents a solution to this challenge by producing meat that resembles traditionally produced meat, but with significantly less land use. Decellularized plant scaffolds, such as spinach leaves, have been shown to be a suitable edible scaffold for growing animal muscle, enabling cultured cells to grow and organize into three-dimensional structures that mimic the texture and flavor of conventionally produced meat. However, the use of freshwater to remove the intact extracellular material from these plants remains a concern, particularly when considering scaling up the production process. In this study, two protocols were used, 1X SDS and Boom Sauce, to decellularize spinach leaves with both distilled water and ocean water. The decellularization process was confirmed by histology, which showed an absence of cell nuclei, DNA and protein quantification. Results showed that spinach decellularized with ocean water contained 9.9 ± 1.4 ng DNA/mg tissue, which is comparable to the 9.2 ± 1.1 ng DNA/mg tissue obtained with DI water. These findings suggest that decellularized spinach leaves using ocean water hold promise as an eco-friendly and cost-effective scaffold for laboratory-grown meat production, which could ultimately transform the meat industry by providing a sustainable alternative to traditional animal farming practices while reducing freshwater use.

Keywords: cellular agriculture, plant scaffold, decellularization, ocean water usage

Procedia PDF Downloads 70