Search results for: board structure

Authors: Ahmadreza Ebadati, Asaad Y. Shamseldin, Amin Ghadirian

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Seawall geometry plays a crucial role in mitigating wave impacts, though detailed exploration of its manipulation is limited. This study delves into the effects of varying cross-shore seawall geometry on the dynamics of wave impacts, with a particular focus on vertical seawalls. Inspired by foundational insights linking seawall shape to hydraulic efficiency, this investigation centres on how alterations in seawall geometry can influence wave energy dissipation and subsequent wave impacts. The study investigates the 2D interaction of regular waves with a period of 2.1s with a vertical seawall and berm featuring small-scale cross-shore protrusions and recesses. Utilising OpenFOAM® simulations and a k-ω SST turbulence model, this investigation compares results to a base case simulation, which is partially calibrated with experimental data from a flume study. The analysis evaluates various geometric modifications, specifically interchanged protrusions and recesses at different heights and orientations along the seawall. Findings suggest that specific configurations, such as interchanged protrusions and recesses, can mitigate initial impact forces, while certain arrangements may intensify subsequent impacts. Key insights include the identification of geometry configurations that can effectively reduce the force impulse of slamming waves on coastal structures and potentially decrease the frequency and cost of seawall maintenance. This research contributes to the field by advancing the understanding of how seawall geometry influences wave forces and by providing actionable insights for the design of more resilient seawall structures. Further exploration of seawall geometry variation is recommended, advocating additional case studies to optimise designs tailored to specific coastal environments.

Keywords: seawall geometry, wave impact loads, numerical simulation, coastal engineering, wave-structure interaction

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Authors: M. F. Wu, F. T. Cheng, C. S. Wu, M. C. Tan

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It is a critical time to upgrade technology and increase value added with manufacturing skills developing and management strategies that will highly satisfy the customers need in the precision machinery global market. In recent years, the supply side, each precision machinery manufacturers in each country are facing the pressures of price reducing from the demand side voices that pushes the high-end precision machinery manufacturers adopts low-cost and high-quality strategy to retrieve the market. Because of the trend of the global market, the manufacturers must take price reducing strategies and upgrade technology of low-end machinery for differentiations to consolidate the market. By using six key success factors (KSFs), customer perceived value, customer satisfaction, customer service, product design, product effectiveness and machine structure quality are causal conditions to explore the impact of competitive advantage of the enterprise, such as overall profitability and product pricing power. This research uses key success paths (KSPs) approach and f/s QCA software to explore various combinations of causal relationships, so as to fully understand the performance level of KSFs and business objectives in order to achieve competitive advantage. In this study, the combination of a causal relationships, are called Key Success Paths (KSPs). The key success paths guide the enterprise to achieve the specific outcomes of business. The findings of this study indicate that there are thirteen KSPs to achieve the overall profitability, sixteen KSPs to achieve the product pricing power and seventeen KSPs to achieve both overall profitability and pricing power of the enterprise. The KSPs provide the directions of resources integration and allocation, improve utilization efficiency of limited resources to realize the continuous vision of the enterprise.

Keywords: precision machinery industry, key success factors (KSFs), key success paths (KSPs), overall profitability, product pricing power, competitive advantages

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Authors: Armand Okende, Benjamin Beaumont

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Introduction: Deforestation is a change in the structure and composition of flora and fauna, which leads to a loss of biodiversity, production of goods and services and an increase in fires. It concerns vast territories in tropical zones particularly; this is the case of the territory of Bolobo in the current province of Maï- Ndombe in the Democratic Republic of Congo. Indeed, through this study between 2001 and 2018, we believe that it was important to show and analyze quantitatively the important forests changes and analyze quantitatively. It’s the overall objective of this study because, in this area, we are witnessing significant deforestation. Methodology: Mapping and quantification are the methodological approaches that we have put forward to assess the deforestation or forest changes through satellite images or raster layers. These satellites data from Global Forest Watch are integrated into the GIS software (GRASS GIS and Quantum GIS) to represent the loss of forest cover that has occurred and the various changes recorded (e.g., forest gain) in the territory of Bolobo. Results: The results obtained show, in terms of quantifying deforestation for the periods 2001-2006, 2007-2012 and 2013-2018, the loss of forest area in hectares each year. The different change maps produced during different study periods mentioned above show that the loss of forest areas is gradually increasing. Conclusion: With this study, knowledge of forest management and protection is a challenge to ensure good management of forest resources. To do this, it is wise to carry out more studies that would optimize the monitoring of forests to guarantee the ecological and economic functions they provide in the Congo Basin, particularly in the Democratic Republic of Congo. In addition, the cartographic approach, coupled with the geographic information system and remote sensing proposed by Global Forest Watch using raster layers, provides interesting information to explain the loss of forest areas.

Keywords: deforestation, loss year, forest change, remote sensing, drivers of deforestation

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Authors: A. Camões, M. Ferreira Dias, M. Amorim

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In recent years, the social economy is increasingly seen as a viable means to address social problems. Social enterprises, as well as public projects and initiatives targeted to meet social purposes, offer organizational models that assume heterogeneity, flexibility and adaptability to the ‘real world and real problems’. Despite the growing popularity of social initiatives, decision makers still face a paucity in what concerns the available models and tools to adequately assess its sustainability, and its impacts, notably the nature of its contribution to economic growth. This study was carried out at the local level, by analyzing the social impact initiatives and projects promoted by the Municipality of Albergaria-a-Velha (Câmara Municipal de Albergaria-a-Velha -CMA), a municipality of 25,000 inhabitants in the central region of Portugal. This work focuses on the challenges related to the qualifications and employability of citizens, which stands out as one of the key concerns in the Portuguese economy, particularly expressive in the context of small-scale cities and inland territories. The study offers a characterization of the Municipality, its socio-economic structure and challenges, followed by an exploratory analysis of multiple sourced data, collected from the CMA's documental sources as well as from privileged informants. The purpose is to conduct detailed analysis of the CMA's social projects, aimed at characterizing its potential impact for the model of qualifications and employability of the citizens of the Municipality. The study encompasses a discussion of the socio-economic profile of the municipality, notably its asymmetries, the analysis of the social projects and initiatives, as well as of data derived from inquiry actors involved in the implementation of the social projects and its beneficiaries. Finally, the results obtained with the Better Life Index will be included. This study makes it possible to ascertain if what is implicit in the literature goes to the encounter of what one experiences in reality.

Keywords: measurement, municipalities, social economy, social impact

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Authors: Lizelle Ramaccio Calvino

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Article 3 of the United Nations Convention on the Rights of Child states that 'The best interests of the child must be a top priority in all decisions and actions that affect children.' This stance is also echoed in terms of article 20 of the African Charter on the Rights and Welfare of the Child. South Africa, as a signatory of the aforesaid international and national conventions, constitutionalised the best interest of the child in terms of section 28(2) of the Republic of South Africa, 1996. Section 28(2) provides that '[A] child’s best interests are of paramount importance in every matter concerning the child.' The application of 'the best interests of the child' principle is consequently applicable in all fields of South African law, including matrimonial law. Two separate but equal Acts regulate civil marriages in South Africa, namely the Marriage Act 25 of 1961 and the Civil Union Act 17 of 2006. Customary marriages are regulated by the Recognition of Customary Marriages Act 120 of 1998. In terms of the Marriage Act and the Recognition of Customary Marriages Act, a minor may (provided he/she obtains the required consent) enter into a marriage. Despite the aforesaid, section 1 of the Civil Union Act categorically prohibits a minor from entering into a civil union. The article will first determine whether the ban of minors from entering into a civil union undermines the 'the best interests of the child' principle, and if so, whether it is in violation of the Constitution as well as international and national conventions. In addition, the article will critically analyse whether the application of the Marriage Act and the Civil Union Act (dual Acts) result in disparity within the South African marriage law framework, and if so, whether such discrepancy violates same-sex couples’ right (in particular a same-sex minor) to equality before the law and to have their dignity protected. The article intends, through the application of a qualitative research methodology and by way of a comparative analyses of international and domestic laws, consider whether a single well-defined structure such as the Dutch marriage law system would not be an improved alternative to address the existing paradox resulting from the application of an Act that undermines 'the best interest of the child' principle. Ultimately the article proposes recommendations for matrimonial law reform.

Keywords: best interests of the child, civil marriage, civil union, minor

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Authors: Heiko Weiß, Andreas Meister, Christoph Ament, Nils Dreifke

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Linear actuators are deployed in a wide range of applications. This paper presents the modeling and system identification of a variable excited linear direct drive (LDD). The LDD is designed based on linear hybrid stepper technology exhibiting the characteristic tooth structure of mover and stator. A three-phase topology provides the thrust force caused by alternating strengthening and weakening of the flux of the legs. To achieve best possible synchronous operation, the phases are commutated sinusoidal. Despite the fact that these LDDs provide high dynamics and drive forces, noise emission limits their operation in calm workspaces. To overcome this drawback an additional excitation of the magnetic circuit is introduced to LDD using additional enabling coils instead of permanent magnets. The new degree of freedom can be used to reduce force variations and related noise by varying the excitation flux that is usually generated by permanent magnets. Hence, an identified simulation model is necessary to analyze the effects of this modification. Especially the force variations must be modeled well in order to reduce them sufficiently. The model can be divided into three parts: the current dynamics, the mechanics and the force functions. These subsystems are described with differential equations or nonlinear analytic functions, respectively. Ordinary nonlinear differential equations are derived and transformed into state space representation. Experiments have been carried out on a test rig to identify the system parameters of the complete model. Static and dynamic simulation based optimizations are utilized for identification. The results are verified in time and frequency domain. Finally, the identified model provides a basis for later design of control strategies to reduce existing force variations.

Keywords: force variations, linear direct drive, modeling and system identification, variable excitation flux

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Authors: Vladimir Klepikov

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Countries of Central and Southern Europe have a typical feature: oil consumption in the region exceeds own commodity production capacity by far. So crude oil import prevails in the region’s crude oil consumption structure. Transportation using marine and pipeline transport is a common method of the imported oil delivery in the region. For certain refineries, in addition to possible transportation by oil pipelines from seaports, oil is delivered from Russian oil fields. With the view to these specific features and geographic location of the region’s refineries, three ways of imported oil delivery can be singled out: oil delivery by tankers to the port and subsequent transportation by pipeline transport of the port and the refinery; oil delivery by tanker fleet to the port and subsequent transportation by oil trunk pipeline transport; oil delivery from the fields by oil trunk pipelines to refineries. Oil is also delivered by road, internal water, and rail transport. However, the volumes transported this way are negligible in comparison to the three above transportation means. Multimodal oil transportation to refineries using the pipeline and marine transport is one of the biggest cargo flows worldwide. However, in scientific publications this problem is considered mainly for certain modes of transport. Therefore, this study is topical. To elaborate an efficient transportation policy of crude oil supply to Central and Southern Europe, in this paper the geographic concentration of oil refineries was determined and the capacities of the region’s refineries were assessed. The quantitative analysis method is used as a tool. The port infrastructure and the oil trunk pipeline system capacity were assessed in terms of delivery of raw materials to the refineries. The main groups of oil consuming countries were determined. The trends of crude oil production in the region were reviewed. The changes in production capacities and volumes at refineries in the last decade were shown. Based on the revealed refining trends, the scope of possible crude oil supplies to the refineries of the region under review was forecast. The existing transport infrastructure is able to handle the increased oil flow.

Keywords: European region, infrastructure, oil terminal capacity, pipeline capacity, refinery capacity, tanker draft

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Authors: Othman E. Othman, Hassan R. Darwish, Amira M. Nowier

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Lactoferrin (LF) is a multifunctional protein involved in economically production traits like milk protein composition and skeletal structure in small ruminants including sheep and goat. So, LF gene - with its genetic polymorphisms associated with production traits - is considered a candidate genetic marker used in marker-assisted selection in goats. This study aimed to identify the different alleles and genotypes of this gene in three Egyptian goat breeds using PCR-SSCP (polymerase chain reaction-single-strand conformation polymorphism) and DNA sequencing. Genomic DNA was extracted from 120 animals belonging to Barki, Zaraibi, and Damascus goat breeds. Using specific primers, PCR amplified 247-bp fragments from exon 2 of LF goat gene. The PCR products were subjected to Single-Strand Conformation Polymorphism (SSCP) technique. The results showed the presence of two genotypes GG and AG in the tested animals. The frequencies of both genotypes varied among the three tested breeds with the highest frequencies of GG genotype in all tested goat breeds. The sequence analysis of PCR products representing these two detected genotypes declared the presence of an SNP (single nucleotide polymorphisms) substitution (G/A) among G and A alleles of this gene. The association between different LF genotypes and milk composition as well as body measurement was estimated. The comparison showed that the animals possess AG genotypes are superior over those with GG genotypes for different parameters of milk protein compositions and skeletal structures. This finding declared that allele A of LF gene is considered the promising marker for the productive traits in goat. In conclusion, the Egyptian goat breeds will be needed to enhance their milk protein composition and growth trait parameters through the increasing of allele A frequency in their herds depending on the superior production traits of this allele in goats.

Keywords: lLactoferrin gene, PCR-SSCP, SNPs, Egyptian goat

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Authors: Tansa Nisan Gunerhan

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Dementia comes in different forms, including Alzheimer's disease. The most common dementia diagnosis among elderly individuals is Alzheimer's disease. On average, for patients with Alzheimer’s, life expectancy is around 4-8 years after the diagnosis; however, expectancy can go as high as twenty years or more, depending on the shrinkage of the brain. Normally, along with aging, the brain shrinks at some level but doesn’t lose a vast amount of neurons. However, Alzheimer's patients' neurons are destroyed rapidly; hence problems with loss of memory, communication, and other metabolic activities begin. The toxic changes in the brain affect the stability of the neurons. Beta-amyloid and tau are two proteins that are believed to play a role in the development of Alzheimer's disease through their toxic changes. Beta-amyloid is a protein that is produced in the brain and is normally broken down and removed from the body. However, in people with Alzheimer's disease, the production of beta-amyloid increases, and it begins to accumulate in the brain. These plaques are thought to disrupt communication between nerve cells and may contribute to the death of brain cells. Tau is a protein that helps to stabilize microtubules, which are essential for the transportation of nutrients and other substances within brain cells. In people with Alzheimer's disease, tau becomes abnormal and begins to accumulate inside brain cells, forming neurofibrillary tangles. These tangles disrupt the normal functioning of brain cells and may contribute to their death, forming amyloid plaques which are deposits of a protein called amyloid-beta that build up between nerve cells in the brain. The accumulation of amyloid plaques and neurofibrillary tangles in the brain is thought to contribute to the shrinkage of brain tissue. As the brain shrinks, the size of the brain may decrease, leading to a reduction in brain volume. Brain atrophy in Alzheimer's disease is often accompanied by changes in the structure and function of brain cells and the connections between them, leading to a decline in brain function. These toxic changes that accumulate can cause symptoms such as memory loss, difficulty with thinking and problem-solving, and changes in behavior and personality.

Keywords: Alzheimer, amyloid-beta, brain atrophy, neuron, shrinkage

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Authors: Mahshid Davoodpoor, Zahra Shamohammadi Ghahsareh, Saeid Razfar, Alaleh Dabbaghi

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Nowadays, air pollution has become a topic of great concern all over the world. One of the main sources of air pollution is automobile exhaust gas, which introduces a large number of toxic gases, including CO, unburned hydrocarbons (HCs), NOx, and non-methane hydrocarbons (NMHCs), into the air. The application of three-way catalysts (TWCs) is still the most effective strategy to mitigate the emission of these pollutants. Due to the stringent environmental regulations which continuously become stricter, studies on the TWCs are ongoing despite several years of research and development. This arises from the washcoat complexity and the several numbers of parameters involved in the redox reactions. The main objectives of these studies are the optimization of washcoat formulation and the investigation of different coating modes. Perovskite (ABO₃), as a promising class of materials, has unique features that make it versatile to use as an alternative to commonly mixed oxides in washcoats. High catalytic activity for oxidation reactions and its relatively high oxygen storage capacity are important properties of perovskites in catalytic applications. Herein, La₀.₈Ba₀.₂FeO₃ perovskite material was synthesized using the co-precipitation method and characterized by XRD, ICP, and BET analysis. The effect of synthesis conditions, including B site metal (Fe and Co), metal precursor concentration, and dopant (Ba), were examined on the phase purity of the products. The selected perovskite sample was used as one of the components in the TWC formulation to evaluate its catalytic performance through Light-off, oxygen storage capacity, and emission analysis. Results showed a remarkable increment in oxygen storage capacity and also revealed that T50 and emission of CO, HC, and NOx reduced in the presence of perovskite structure which approves the enhancement of catalytic performance for the new washcoat formulation. This study shows the brilliant future of advanced oxide structures in the TWCs.

Keywords: Perovskite, three-way catalyst, PGMs, PGMs reduction

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Authors: Naif A. Haddad

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Greek, Hellenistic and Roman theatre heritage are exposed to multiple risks at varied times or simultaneously. There is no single reason why a theatre building becomes ‘at risk’, as each case has different circumstances which have led to the theatre building decay. There are complicated processes of destruction and distress that show divergence in theatre building materials' decay. Theatre modern use for cultural performances causes much of the risks concerning the physical structure and authenticity of theatre sites. In addition, there are some deterioration and deformations due to previous poor quality restorations and interventions through related excavation and conservation programmes as also risks to authenticity due to new additions. For preventive conservation, theatre natural and anthropogenic risks management can provide a framework for decision making. These risks to ancient theatre heritage may stem from exposure to one or more risk or synergy of many factors. We, therefore, need to link the theatre natural risks to the risks that come from anthropogenic factors associated with social and economic development. However, this requires a holistic approach, and systematic methodology for understanding these risks from various sources while incorporating specific actions, planning and strategies for each specific risk. Elaborating on recent relevant studies, and ERATO and ATHENA EU projects for ancient theaters and odea and general surveys, this paper attempts to discuss the main aspects of the ancient Greek, Hellenistic and Roman theatres risk related issues. Relevant case studies shall also be discussed and investigated to examine frameworks for risk mitigation, and related guidelines and recommendations that provide a systematic approach for sustainable management and planning in relation mainly to ‘compatible use’ of theatre sites.

Keywords: cultural heritage management, European ancient theatres projects, Anthropogenic risks mitigation, sustainable management and planning, preventive conservation, modern use, compatible use

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Authors: Tarali Kalita, Karabi Dutta

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The North Eastern Region of India, with diverse climatic conditions and a wide range of ecological habitats, makes an ideal natural abode for a good number of silk-producing insects. Cocoon is the economically important life stage from where silk of economic importance is obtained. In recent years, silk-based biomaterials have gained considerable attention, which is dependent on the structure and properties of the silkworm cocoons as well as silk yarn. The present investigation deals with the morphological study of cocoons, including cocoon color, cocoon size, shell weight and shell ratio of eleven different species of silk insects collected from different regions of North East India. The Scanning Electron Microscopic study and X-ray photoelectron spectroscopy were performed to know the arrangement of silk threads in cocoons and the atomic elemental analysis, respectively. Further, collected cocoons were degummed and reeled/spun on a reeling machine or spinning wheel to know the filament length, linear density and tensile strength by using Universal Testing Machine. The study showed significant variation in terms of cocoon color, cocoon shape, cocoon weight and filament packaging. XPS analysis revealed the presence of elements (Mass %) C, N, O, Si and Ca in varying amounts. The wild cocoons showed the presence of Calcium oxalate crystals which makes the cocoons hard and needs further treatment to reel. In the present investigation, the highest percentage of strain (%) and toughness (g/den) were observed in Antheraea assamensis, which implies that the muga silk is a more compact packing of molecules. It is expected that this study will be the basis for further biomimetic studies to design and manufacture artificial fiber composites with novel morphologies and associated material properties.

Keywords: cocoon characterization, north-east India, prospects, silk characterization

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Authors: Arpita Mondal, Aurobinda Routray, Sreeraj Puravankara, Rajashree Biswas

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The most difficult part of designing a battery management system (BMS) is battery modeling. A good battery model can capture the dynamics which helps in energy management, by accurate model-based state estimation algorithms. So far the most suitable and fruitful model is the equivalent circuit model (ECM). However, in real-time applications, the model parameters are time-varying, changes with current, temperature, state of charge (SOC), and aging of the battery and this make a great impact on the performance of the model. Therefore, to increase the equivalent circuit model performance, the parameter estimation has been carried out in the frequency domain. The battery is a very complex system, which is associated with various chemical reactions and heat generation. Therefore, it’s very difficult to select the optimal model structure. As we know, if the model order is increased, the model accuracy will be improved automatically. However, the higher order model will face the tendency of over-parameterization and unfavorable prediction capability, while the model complexity will increase enormously. In the time domain, it becomes difficult to solve higher order differential equations as the model order increases. This problem can be resolved by frequency domain analysis, where the overall computational problems due to ill-conditioning reduce. In the frequency domain, several dominating frequencies can be found in the input as well as output data. The selective frequency domain estimation has been carried out, first by estimating the frequencies of the input and output by subspace decomposition, then by choosing the specific bands from the most dominating to the least, while carrying out the least-square, recursive least square and Kalman Filter based parameter estimation. In this paper, a second order battery model consisting of three resistors, two capacitors, and one SOC controlled voltage source has been chosen. For model identification and validation hybrid pulse power characterization (HPPC) tests have been carried out on a 2.6 Ah LiFePO₄ battery.

Keywords: equivalent circuit model, frequency estimation, parameter estimation, subspace decomposition

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Authors: Kristel Faye Tandog

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The State Owned Enterprise (SOE) or also called Public Enterprise (PE) has been playing a vital role in a country’s social and economic development. Following this idea, this study focused on the Factor Structures of Financial Performance of the Local Economic Enterprises (LEEs) namely: Food Court, Market, Slaughterhouse, and Terminal in Matalam, Cotabato. It aimed to determine the profile of the LEEs in terms of organizational structure, manner of creation, years in operation, source of initial operating requirements, annual operating budget, geographical location, and size or description of the facility. This study also included the different financial ratios of LEE that covered a five year period from Calendar Year 2009 to 2013. Primary data using survey questionnaire was administered to 468 respondents and secondary data were sourced out from the government archives and financial documents of the said LGU. There were 12 dominant factors identified namely: “management”, “enforcement of laws”, “strategic location”, “existence of non-formal competitors”, “proper maintenance”, “pricing”, “customer service”, “collection process”, “rentals and services”, “efficient use of resources”, “staffing”, and “timeliness and accuracy”. On the other hand, the financial performance of the LEE of Matalam, Cotabato using financial ratios needs reformatting. This denotes that refinement as to the following ratios: Cash Flow Indicator, Activity, Profitability and Growth is necessary. The cash flow indicator ratio showed difficulty in covering its debts in successive years. Likewise, the activity ratios showed that the LEE had not been effective in putting its investment at work. Moreover, profitability ratios revealed that it had operated in minimum capacity and had incurred net losses and thus, it had a weak profit performance. Furthermore, growth ratios showed that LEE had a declining growth trend particularly in net income.

Keywords: factor structures, financial performance, financial ratios, state owned enterprises

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Authors: Manish Madappa, Madhavi Gayathri Raman

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The primary vehicle of human communication is language. A breakdown occurring in any aspect of communication may lead to frustration and isolation among the learners and the teachers. Over seven percent of the population in the world currently experience limitations and those children who exhibit a deviant/deficient language acquisition curve even when being in a language rich environment as their peers may be at risk of having a language disorder or language impairment. The difficulty may be in the word level [vocabulary/word knowledge] and/or the sentence level [syntax/morphology) Children with SLI appear to be developing normally in all aspects except for their receptive and/or expressive language skills. Thus, it is utmost importance to identify children with or at risk of SLI so that an early intervention can foster language and social growth, provide the best possible learning environment with special support for language to be explicitly taught and a step in providing continuous and ongoing support. The present study looks at Kannada English bilingual children and works towards identifying children at risk of “specific language impairment”. The study was conducted through an exploratory study which systematically enquired into the narratives of young Kannada-English bilinguals and to investigate the data for story structure in their narrative formulations. Oral narrative offers a rich source of data about a child’s language use in a relatively natural context. The fundamental objective is to ensure comparability and to be more universal and thus allows for the evaluation narrative text competence. The data was collected from 10 class three students at a primary school in Mysore, Karnataka and analyzed for macrostructure component reflecting the goal directed behavior of a protagonist who is motivated to carry out some kind of action with the intention of attaining a goal. The results show that the children exhibiting a deviation of -1.25 SD are at risk of SLI. Two learners were identified to be at risk of Specific Language Impairment with a standard deviation of more the 1.25 below the mean score.

Keywords: bilingual, oral narratives, SLI, macrostructure

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Authors: Carolina Payares-Asprino

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Dual-phase duplex stainless steel comprised of ferrite and austenite has shown high strength and corrosion resistance in many aggressive environments. Joining duplex alloys is challenging due to several embrittling precipitates and metallurgical changes during the welding process. The welding parameters strongly influence the quality of a weld joint. Therefore, it is necessary to quantify the weld bead’s integral properties as a function of welding parameters, especially when part of the weld bead is removed through a machining process due to aesthetic reasons or to couple the elements in the in-service structure. The present study uses the existing stress-strain model to predict the stress-strain curves for duplex stainless-steel welds under different welding conditions. Having mathematical expressions that predict the shape of the stress-strain curve is advantageous since it reduces the experimental work in obtaining the tensile test. In analysis and design, such stress-strain modeling simplifies the time of operations by being integrated into calculation tools, such as the finite element program codes. The elastic zone and the plastic zone of the curve can be defined by specific parameters, generating expressions that simulate the curve with great precision. There are empirical equations that describe the stress-strain curves. However, they only refer to the stress-strain curve for the stainless steel, but not when the material is under the welding process. It is a significant contribution to the applications of duplex stainless steel welds. For this study, a 3x3 matrix with a low, medium, and high level for each of the welding parameters were applied, giving a total of 27 weld bead plates. Two tensile specimens were manufactured from each welded plate, resulting in 54 tensile specimens for testing. When evaluating the four models used to predict the stress-strain curve in the welded specimens, only one model (Rasmussen) presented a good correlation in predicting the strain stress curve.

Keywords: duplex stainless steels, modeling, stress-stress curve, tensile test, welding

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Authors: Orod Zarrin, Mohesn Ramezan Shirazi, Hassan Moniri

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The use of pile foundations technique is developed to support structures and buildings on soft soil. The most important dynamic load that can affect the pile structure is earthquake vibrations. From the 1960s the comprehensive investigation of pile foundations during earthquake excitation indicate that, piles are subject to damage by affecting the superstructure integrity and serviceability. The main part of these research has been focused on the behavior of liquefiable soil and lateral spreading load on piles. During an earthquake, two types of stresses can damage the pile head, inertial load that is caused by superstructure and deformation which caused by the surrounding soil. Soil deformation and inertial load are associated with the acceleration developed in an earthquake. The acceleration amplitude at the ground surface depends on the magnitude of earthquakes, soil properties and seismic source distance. According to the investigation, the damage is between the liquefiable and non-liquefiable layers and also soft and stiff layers. This damage crushes the pile head by increasing the inertial load which is applied by the superstructure. On the other hand, the cracks on the piles due to the surrounding soil are directly related to the soil profile and causes cracks from small to large. And researchers have been listed the large cracks reason such as liquefaction, lateral spreading and inertial load. In the field of designing, elastic response of piles are always a challenge for designer in liquefaction soil, by allowing deflection at top of piles. Moreover, absence of plastic hinges in piles should be insured, because the damage in the piles is not observed directly. In this study, the performance and behavior of pile foundations during liquefaction and lateral spreading are investigated. And emphasize on the soil behavior in the liquefiable and non-liquefiable layers by different aspect of piles damage such as ranking, location and degree of damage are going to discuss.

Keywords: self-compacting concrete, fiber, tensile strength, post-cracking, direct and inverse technique

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Authors: Siah Koka, Rony Swennen

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Arumeru district is located in Arusha region in Upper Pangani basin in Tanzania. Economically it is dominated with agricultural activities. Banana, coffee, maize, beans, tomatoes, and cassava are the most important food and cash crops. This paper characterized the banana-based farming system of Arumeru district, evaluates its sustainability as well as research needs. The household questionnaire was performed on-site and on farm observation. Transect walk also involved to identify different agro- ecological zones. Results show that farm holdings (home gardens) are smaller than a hectare (0.7 ha) and continue to fragment as population continues to grow. Banana cultivation is the backbone of the farming systems present both in the upland and plains. In the upper belt banana found their place in the forest, which form the home garden structure typical to East African highland banana production systems. However, in the plains, cultivation is done in monoculture and depends heavily on irrigation. We found slightly less cultivars present and hypothetically more pest and disease pressure. This was mainly seen for Fusarium oxysporum species, which eradicates susceptible cultivars such as Mchare cultivars rapidly given the method of irrigation. The smaller permanent upland home garden plots provide thus a more suitable environment where banana perform better. It should be noted that findings indicated good performance to occur in the less suitable plains too. Good management is believed to be the most influencing factor, although our survey failed in identifying them. Population pressure is currently pushing the sustainable system in the uplands to its boundaries. Nutrient mining, deforestation and changing rain patterns threat production not only on Mt. Meru but on a global scale.

Keywords: Arumeru district, banana-based farming system, Tanzania, Arumeru district

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Authors: Indu ray

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In today’s digital world the internet is already flooded with information on how to master grammar in a foreign language. It is well known that one cannot master a language without grammar. Grammar is the backbone of any language. Without grammar there would be no structure to help you speak/write or listen/read. Successful communication is only possible if the form and function of linguistic utterances are firmly related to one another. Grammar has its own rules of use to formulate an easier-to-understand language. Like a tool, grammar formulates our thoughts and knowledge in a meaningful way. Every language has its own grammar. With grammar, we can quickly analyze whether there is any action in this text: (Present, past, future). Knowledge of grammar is an important prerequisite for mastering a foreign language. What’s most important is how teachers can make grammar lessons more interesting for students and thus promote grammar skills more successfully. Through this paper, we discuss a few important methods like (Interactive Grammar Exercises between students, Interactive Grammar Exercise between student to teacher, Grammar translation method, Audio -Visual Method, Deductive Method, Inductive Method). This paper is divided into two sections. In the first part, brief definitions and principles of these approaches will be provided. Then the possibility and the case of combination of this approach will be analyzed. In the last section of the paper, I would like to present a survey result conducted at my university on a few methods to quickly learn grammar in Foreign Language. We divided the Grammatical Skills in six Parts. 1.Grammatical Competence 2. Speaking Skills 3. Phonology 4. The syntax and the Semantics 5. Rule 6. Cognitive Function and conducted a survey among students. From our survey results, we can observe that phonology, speaking ability, syntax and semantics can be improved by inductive method, Audio-visual Method, and grammatical translation method, for grammar rules and cognitive functions we should choose IGE (teacher-student) method. and the IGE method (pupil-pupil). The study’s findings revealed, that the teacher delivery Methods should be blend or fusion based on the content of the Grammar.

Keywords: innovative method, grammatical skills, audio-visual, translation

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Authors: Sellidj Abdelaziz, Lebaili Soltane

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A cobalt-based alloy type Co-Cr-Ni-WC was deposited by plasma transferred arc projection (PTA) on a stainless steel valve. The alloy is characterized at the equilibrium by a solid solution Co (γ) mainly dendritic, and eutectic carbides M₇C₃ and ηM₆C. At the deposit/substrate interface, this microstructure is modified by the fast cooling mode of the alloy when applied in the liquid state on the relatively cold steel substrate. The structure formed in this case is heterogeneous and metastable phases can occur and evolve over temperature service. Coating properties and reliability are directly related to microstructures formed during deposition. We were interested more particularly in this microstructure formed during the solidification of the deposit in the region of the interface joining the soldered couple and its evolution during cyclic heat treatments at temperatures similar to those of the thermal environment of the valve. The characterization was carried out by SEM-EDS microprobe CAMECA, XRD, and micro hardness profiles. The deposit obtained has a linear and regular appearance that is free of cracks and with little porosity. The morphology of the microstructure represents solidification stages that are relatively fast with a temperature gradient high at the beginning of the interface by forming a plane front solid solution Co (γ). It gradually changes with the decreasing temperature gradient by getting farther from the junction towards the outer limit of the deposit. The matrix takes the forms: cellular, mixed (cells and dendrites) and dendritic. Dendritic growth is done according to primary ramifications in the direction of the heat removal which takes place in the direction perpendicular to the interface, towards the external surface of the deposit, following secondary and tertiary undeveloped arms. The eutectic carbides M₇C₃ and ηM₆C formed are very thin and are located in the intercellular and interdendritic spaces of the solid solution Co (γ).

Keywords: Co-Ni-Cr-W-C alloy, solid deposit, microstructure, carbides, cyclic heat treatment

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Authors: Ali Akbar Jabbari

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The present study assessed the acquisition of L3 French direct objects by Persian speakers who had already learned English as their L2. The ultimate goal of this paper is to extend the current knowledge about the CLI phenomenon in the realm of third language acquisition by examining the role of Persian and English as background languages and learners’ English level of proficiency in their performance on French direct object. To fulfill this, the assumptions of three L3 hypotheses, namely L1 Transfer, L2 Status Factor, and Cumulative Enhancement Model, were examined. The research sample was comprised of 40 undergraduate students in the fields of English language and literature and translation studies at Birjand University in Iran. According to the English proficiency level of learners revealed by the Quick Oxford English Placement test, the participants were grouped as upper intermediate and lower intermediate. A grammaticality judgment and a translation test were administered to gather the required data on learners' comprehension and production of the desired structure in French. It was demonstrated that the rate of positive transfer from previously learned languages was more potent than the rate of negative transfer. A Comparison of groups' performances revealed a significant difference between upper and lower intermediate groups in positing French direct objects correctly. However, the upper intermediate group did not significantly differ from the lower intermediate group in negative transfer. It can be said that by increasing the L2 proficiency of the learners, they could use their previous linguistic knowledge more efficiently. Although further examinations are needed, the current study contributed to a better characterization of cross-linguistic influence in third language acquisition. The findings help French teachers and learners to positively exploit the prior knowledge of Persian and English and apply it in in the multilingual context of French direct object's teaching and learning process.

Keywords: Cross-Linguistic Influence, Persian, French & English Direct Object, Third Language Acquisition, Language Transfer

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Authors: Intesar Ibrahim

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Large-scale Libyan emigration is a relatively new phenomenon. Most of the Libyan families in the UK are new immigrants, unlike the other neighbouring countries of Egypt, Tunisia, Algeria and even Sudan. Libyans have no particular history of large-scale migration. On the other hand, many Libyan families live in modest homes located in large Muslim communities of Pakistanis and Yemenis. In the UK as a whole, there are currently 16 Libyan schools most of which are run during the weekend for children of school age. There are three such weekend schools in Sheffield that teach a Libyan school curriculum, and Libyan women and men run these schools. Further, there is also a Masjid (mosque) that is operated by Libyans, beside the other Masjids in the city, which most of the Libyan community attend for prayer and for other activities such as writing marriage contracts. The presence of this Masjid increases the attraction for Libyans to reside in the Sheffield area. This paper studies how Libyan immigrants in the UK make their decisions on their housing and living environment in the UK. Libyan residents in the UK come from different Libyan regions, social classes and lifestyles; this may have an impact on their choices in the interior designs of their houses in the UK. A number of case studies were chosen from Libyan immigrants who came from different types of dwellings in Libya, in order to compare with their homes and their community lifestyle in the UK and those in Libya. This study explores the meaning and the ways of using living rooms in Libyan emigrants’ houses in the UK and compares those with those in their houses back in their home country. For example, the way they set up furniture in rooms acts as an indicator of the hierarchical structure of society. The design of furniture for Libyan sitting rooms for floor-seating is different from that of the traditional English sitting room. The paper explores the identity and cultural differences that affected the style and design of the living rooms for Libyan immigrants in the UK. The study is carried out based on the "production of space" theory that any culture has its needs, style of living and way of thinking. I argue that the study found more than 70% of Libyan immigrants in the UK still furnish the living room in their traditional way (flooring seating).

Keywords: place, identity, culture, immigrants

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Authors: Emile Niringiyimana, LI Ji Qing, Giovanni Dushimimana, Virginie Umwere

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The development and utilization of renewable energy (RE) can not only effectively reduce carbon dioxide (CO2) emissions, but also became a solution to electricity shortage mitigation in rural areas. Hybrid RE systems are promising ways to provide consistent and continuous power for isolated areas. This work investigated the prospect and cost effectiveness of hybrid system complementarity between a 100kW solar PV system and a small-scale 200kW hydropower station in the South of Rwanda. In order to establish the optimal size of a RE system with adequate sizing of system components, electricity demand, solar radiation, hydrology, climate data are utilized as system input. The average daily solar radiation in Rukarara is 5.6 kWh/m2 and average wind speed is 3.5 m/s. The ideal integrated RE system, according to Homer optimization, consists of 91.21kW PV, 146kW hydropower, 12 x 24V li-ion batteries with a 20kW converter. The method of enhancing such hybrid systems control, sizing and choice of components is to reduce the Net present cost (NPC) of the system, unmet load, the cost of energy and reduction of CO2. The power consumption varies according to dominant source of energy in the system by controlling the energy compensation depending on the generation capacity of each power source. The initial investment of the RE system is $977,689.25, and its operation and maintenance expenses is $142,769.39 over a 25-year period. Although the investment is very high, the targeted profits in future are huge, taking into consideration of high investment in rural electrification structure implementations, tied with an increase of electricity cost and the 5 years payback period. The study outcomes suggest that the standalone hybrid PV-Hydropower system is feasible with zero pollution in Rukara community.

Keywords: HOMER optimization, hybrid power system, renewable energy, NPC and solar pv systems

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Authors: Shengxin Yu

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Earthquakes can cause varying degrees of damage to building and bridge structures. Traditional laminated natural rubber bearings (NRB) exhibit inadequate energy dissipation and restraint, particularly under near-fault ground motions, resulting in excessive displacements in the superstructure. This paper presents a composite natural rubber bearing (NFUD-NRB) incorporating two types of shape memory alloy (SMA) U-shaped dampers (UD). The bearing exhibits adjustable features, predominantly characterized by partial self-centering and multi-level energy dissipation, facilitated by nickel-titanium-based SMA (NiTi-SMA) and iron-based SMA (Fe-SMA) UDs. The hysteresis characteristics of NFUD-NRB can be tailored by manipulating the configuration of NiTi-SMA and Fe-SMA UDs. Firstly, the proposed bearing's geometric configuration and working principle are introduced. The rationality of the modeling strategy for the bearing is validated through existing experimental results. Parameterized numerical simulations are subsequently performed to investigate the partially self-centering behavior of NFUD-NRB. The findings indicate that NFUD-NRB can attain the anticipated nonlinear behavior and deliver adequate energy dissipation. Finally, the impact of NFUD-NRB on improving the seismic resilience of highway bridges is examined using the OpenSees software, with particular emphasis on the seismic performance of NFUD-NRB under near-fault ground motions. System-level analysis reveals that bridge systems equipped with NFUD-NRBs exhibit satisfactory residual deformations and higher energy dissipation than those equipped with traditional NRBs. Moreover, NFUD-NRB markedly mitigates the detrimental impacts of near-fault ground motions on the main structure of bridges.

Keywords: partially self-centering behavior, energy dissipation, natural rubber bearing, shape memory alloy, U-shaped damper, numerical investigation, near-fault ground motion

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Authors: Hubert Feiglstorfer

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The technique of making terrazzo has been known since ancient times. During the Roman Empire, known as opus signinum, at the time of the Renaissance, known as composto terrazzo marmorino or at the turn of the 19th and 20th centuries, the use of terrazzo experienced a common use in Europe. In Asia, especially in the Himalayas and the Tibetan highlands, a particular floor and roof manufacturing technique is commonly used for about 1500 years, known as arga. The research question in this contribution asks for technical and cultural-historical synergies of these floor-making techniques. The making process of an arga floor shows constructive parallels to the European terrazzo. Surface processing by grinding, burnishing and sealing, in particular, reveals technological similarities. The floor structure itself, on the other hand, shows differences, for example in the use of hydraulic aggregate in the terrazzo, while the arga floor is used without hydraulic material, but the result of both techniques is a tight, water-repellent and shiny surface. As part of this comparative study, the materials, processing techniques and quality features of the two techniques are compared and parallels and differences are analysed. In addition to text and archive research, the methods used are results of material analyses and ethnographic research such as participant observation. Major findings of the study are the investigation of the mineralogical composition of arga floors and its comparison with terrazzo floors. The study of the cultural-historical context in which both techniques are embedded will give insight into technical developments in Europe and Asia, parallels and differences. Synergies from this comparison let possible technological developments in the production, conservation and renovation of European terrazzo floors appear in a new light. By making arga floors without cement-based aggregates, the renovation of historical floors from purely natural products and without using energy by means of a burning process can be considered.

Keywords: European and Asian crafts, material culture, floor making technology, terrazzo, arga, Tibetan building traditions

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Authors: Wei-Ting Hung

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Inbound tourist expenditure might not only have influenced by individual tourist characteristics but may also be affected by nationality characteristics. The cross national distance effects on tourist consumption behavior should be incorporated in the analytical framework. Additionally, the often used factor analysis, cluster analysis and regression analysis overlook the hierarchical tourist consumption data structure and may lead to misleading results. The objectives of the present study were twofold. First, we propose a multilevel model that takes individual and cross-national differences into account under a hierarchical framework. Second, we further sought to determine the types of cross-national differences affecting tourist expenditure. Thus, this study incorporates the individual tourist effects and cross national distance effects simultaneously, uses the data of 2010 Annual Survey Report on Visitors’ Expenditure and Trends in Taiwan to investigate the determinants of inbound tourist expenditure. Multilevel analysis was used to investigate the influence of individual tourist effects and cross national distance effects on inbound tourist expenditure. The empirical results show that cross national distance plays a crucial role in tourist consumption behavior. Our findings also indicate age and income have positive influence on tourism expenditure., whereas education and gender do not have significant impact. Regarding macro-level factors, geographic and cultural differences exhibited significant positive relationships on tourism expenditure, while economic differences did not. Based on the above empirical results, it is suggested that tour operators should take tourists’ individual attributes, particularly their income and age, into consideration when arranging tours. In addition, nationality holds sway over tourists’ consumption behavior, of which geographic and cultural differences are the two major factors at play. The empirical results of this study serve as practical suggestions for tourism marketing strategies and policy implications for government policies.

Keywords: cross national distance, inbound tourist, multilevel analysis, tourist expenditure

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Authors: Mohamed M. A. Abumandour

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The red swamp freshwater crayfish breathe through three types of feather-like trichobranchiate gills; podobranchiae, arthrobranchiae and pleurobranchiae. All gills have the same general structure and appearance; plume-like with single broad setiferous, and single axis. The gill consists of axis with numerous finger-like filaments, having three morphological types; round, pointed and somewhat hooked shaped. The direction of filaments vary according their position; in middle region were nearly perpendicular to gill axis while in the apex were nearly parallel to axis. There were characteristic system of gill spines on; central axis (two types were distinguishable by presence of socket), basal plate, setobranch (long non-branched and short multidenticulate) and on the bilobed epipodal plate. There are four shape of spinated-like distal region of setobranch seta; two pointed processes (longitudinal arrangement and irregular arranged) and two broad processes (transverse triangular and multidenticulate). The bilobed epipodal plate devoid from any filaments and extended from outer side of podobranchiae as triangular basal part then extended between the gills as cord-like middle part then pass under the gill to lies against the thoracic body wall. By SEM, the apical part of bilobed epipodal plate have serrated free border and corrugated surface while the middle part have none serrated free border. There are two methods of gill cleaning mechanism in crayfish; passive and active method. The passive method occurred by; setae of setobranch, branchiostegite, bilobed epipodal plate, setiferous arthrodial lamellae and reversing the respiratory water through a narrow spaced branchial chamber.

Keywords: crayfis, gill spines, setobranch, gill setae, cleaning mechanisms

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Authors: Xiaoyang Zhao, Kaiying Wang

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The choice of stocking density in poultry farming is a potential way for determining welfare level of poultry. However, it is difficult to measure stocking densities in poultry farming because of a lot of variables such as species, age and weight, feeding way, house structure and geographical location in different broiler houses. A method was proposed in this paper to measure the differences of young broilers reared under different stocking densities by sound analysis. Vocalisations of broilers were recorded and analysed under different stocking densities to identify the relationship between sounds and stocking densities. Recordings were made continuously for three-week-old chickens in order to evaluate the variation of sounds emitted by the animals at the beginning. The experimental trial was carried out in an indoor reared broiler farm; the audio recording procedures lasted for 5 days. Broilers were divided into 5 groups, stocking density treatments were 8/m², 10/m², 12/m² (96birds/pen), 14/m² and 16/m², all conditions including ventilation and feed conditions were kept same except from stocking densities in every group. The recordings and analysis of sounds of chickens were made noninvasively. Sound recordings were manually analysed and labelled using sound analysis software: GoldWave Digital Audio Editor. After sound acquisition process, the Mel Frequency Cepstrum Coefficients (MFCC) was extracted from sound data, and the Support Vector Machine (SVM) was used as an early detector and classifier. This preliminary study, conducted in an indoor reared broiler farm shows that this method can be used to classify sounds of chickens under different densities economically (only a cheap microphone and recorder can be used), the classification accuracy is 85.7%. This method can predict the optimum stocking density of broilers with the complement of animal welfare indicators, animal productive indicators and so on.

Keywords: broiler, stocking density, poultry farming, sound monitoring, Mel Frequency Cepstrum Coefficients (MFCC), Support Vector Machine (SVM)

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Authors: Nam-Hee Kim, Jang-Hoon Ko, Kwon-Hee Lee

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A relief valve is a mechanical element to keep safety by controlling high pressure. Usually, the high pressure is relieved by using the spring force and letting the fluid to flow from another way out of system. When its normal pressure is reached, the relief valve can return to initial state. The relief valve in this study has been applied for pressure vessel, evaporator, piping line, etc. The relief valve should be designed for smooth operation and should satisfy the structural safety requirement under operating condition. In general, the structural analysis is performed by following fluid flow analysis. In this process, the FSI (Fluid-Structure Interaction) is required to input the force obtained from the output of the flow analysis. Firstly, this study predicts the velocity profile and the pressure distribution in the given system. In this study, the assumptions for flow analysis are as follows: • The flow is steady-state and three-dimensional. • The fluid is Newtonian and incompressible. • The walls of the pipe and valve are smooth. The flow characteristics in this relief valve does not induce any problem. The commercial software ANSYS/CFX is utilized for flow analysis. On the contrary, very high pressure may cause structural problem due to severe stress. The relief valve is made of body, bonnet, guide, piston and nozzle, and its material is stainless steel. To investigate its structural safety, the worst case loading is considered as the pressure of 700 bar. The load is applied to inside the valve, which is greater than the load obtained from FSI. The maximum stress is calculated as 378 MPa by performing the finite element analysis. However, the value is greater than its allowable value. Thus, an alternative design is suggested to improve the structural performance through case study. We found that the sensitive design variable to the strength is the shape of the nozzle. The case study is to vary the size of the nozzle. Finally, it can be seen that the suggested design satisfy the structural design requirement. The FE analysis is performed by using the commercial software ANSYS/Workbench.

Keywords: relief valve, structural analysis, structural design, strength, safety factor

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Authors: Seungho Shin, Keunwoo Choi, Ali Akbar, Sukkee Um

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In this study, the nanoscale transport properties and catalyst utilization of vertically aligned carbon nanotube (VACNT) catalyst layers are computationally predicted by the three-dimensional lattice Boltzmann simulation based on the quasi-random nanostructural model in pursuance of fuel cell catalyst performance improvement. A series of catalyst layers are randomly generated with statistical significance at the 95% confidence level to reflect the heterogeneity of the catalyst layer nanostructures. The nanoscale gas transport phenomena inside the catalyst layers are simulated by the D3Q19 (i.e., three-dimensional, 19 velocities) lattice Boltzmann method, and the corresponding mass transport characteristics are mathematically modeled in terms of structural properties. Considering the nanoscale reactant transport phenomena, a transport-based effective catalyst utilization factor is defined and statistically analyzed to determine the structure-transport influence on catalyst utilization. The tortuosity of the reactant mass transport path of VACNT catalyst layers is directly calculated from the streaklines. Subsequently, the corresponding effective mass diffusion coefficient is statistically predicted by applying the pre-estimated tortuosity factors to the Knudsen diffusion coefficient in the VACNT catalyst layers. The statistical estimation results clearly indicate that the morphological structures of VACNT catalyst layers reduce the tortuosity of reactant mass transport path when compared to conventional catalyst layer and significantly improve consequential effective mass diffusion coefficient of VACNT catalyst layer. Furthermore, catalyst utilization of the VACNT catalyst layer is substantially improved by enhanced mass diffusion and electric current paths despite the relatively poor interconnections of the ion transport paths.

Keywords: Lattice Boltzmann method, nano transport phenomena, polymer electrolyte fuel cells, vertically aligned carbon nanotube

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