Search results for: high gain
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 21386

Search results for: high gain

19856 The Effective Use of the Network in the Distributed Storage

Authors: Mamouni Mohammed Dhiya Eddine

Abstract:

This work aims at studying the exploitation of high-speed networks of clusters for distributed storage. Parallel applications running on clusters require both high-performance communications between nodes and efficient access to the storage system. Many studies on network technologies led to the design of dedicated architectures for clusters with very fast communications between computing nodes. Efficient distributed storage in clusters has been essentially developed by adding parallelization mechanisms so that the server(s) may sustain an increased workload. In this work, we propose to improve the performance of distributed storage systems in clusters by efficiently using the underlying high-performance network to access distant storage systems. The main question we are addressing is: do high-speed networks of clusters fit the requirements of a transparent, efficient and high-performance access to remote storage? We show that storage requirements are very different from those of parallel computation. High-speed networks of clusters were designed to optimize communications between different nodes of a parallel application. We study their utilization in a very different context, storage in clusters, where client-server models are generally used to access remote storage (for instance NFS, PVFS or LUSTRE). Our experimental study based on the usage of the GM programming interface of MYRINET high-speed networks for distributed storage raised several interesting problems. Firstly, the specific memory utilization in the storage access system layers does not easily fit the traditional memory model of high-speed networks. Secondly, client-server models that are used for distributed storage have specific requirements on message control and event processing, which are not handled by existing interfaces. We propose different solutions to solve communication control problems at the filesystem level. We show that a modification of the network programming interface is required. Data transfer issues need an adaptation of the operating system. We detail several propositions for network programming interfaces which make their utilization easier in the context of distributed storage. The integration of a flexible processing of data transfer in the new programming interface MYRINET/MX is finally presented. Performance evaluations show that its usage in the context of both storage and other types of applications is easy and efficient.

Keywords: distributed storage, remote file access, cluster, high-speed network, MYRINET, zero-copy, memory registration, communication control, event notification, application programming interface

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19855 Clarifications on the Damping Mechanism Related to the Hunting Motion of the Wheel Axle of a High-Speed Railway Vehicle

Authors: Barenten Suciu

Abstract:

In order to explain the damping mechanism, related to the hunting motion of the wheel axle of a high-speed railway vehicle, a generalized dynamic model is proposed. Based on such model, analytic expressions for the damping coefficient and damped natural frequency are derived, without imposing restrictions on the ratio between the lateral and vertical creep coefficients. Influence of the travelling speed, wheel conicity, dimensionless mass of the wheel axle, ratio of the creep coefficients, ratio of the track span to the yawing diameter, etc. on the damping coefficient and damped natural frequency, is clarified.

Keywords: high-speed railway vehicle, hunting motion, wheel axle, damping, creep, vibration model, analysis.

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19854 Confidence in Practice of Debate at Senior High School Student in Jakarta, Indonesia

Authors: Arista Mayang Sari Slamet

Abstract:

This study was conducted to see the shape or behavior that shows the attitude of confidence in the practice of debate on science program students in Senior High School. This research is a descriptive qualitative study by explaining the forms of behavior of each indicator (there are ten indicators) confidence of Santrock. Data collection using interviews with Indonesian language teachers, direct observation, and documents. In this study, it was found that there is one item that is not visible indicator of the high school students of class X, which is the fourth item ‘Sitting with others in social activities’. This is caused by the forum examined are debating forum, so there is a social activity can’t be seen. The result of this study there are two students who do not show the behavior of confidence, their name is Dea and Audria (from the pro team). This indicates that the head of a pro team dominated the debate. The time for the debate is 45 minutes. Therefore all students in both of team can’t demonstrate their debate skill. In each team is only dominated by one student. The most common forms of confidence behavior are expressing opinion, look at the other person (speaker), and keeping eye contact with the other person. This indicates that the attitude of confidence by looking at the other person makes them more confident about their opinion. The most uncommon indicators is to direct or instruct to the other person. This shows that the attitude of self-confidence shown by the students isn’t lead.

Keywords: confidence, debate, senior high school, Jakarta

Procedia PDF Downloads 161
19853 Low Enrollment in Civil Engineering Departments: Challenges and Opportunities

Authors: Alaa Yehia, Ayatollah Yehia, Sherif Yehia

Abstract:

There is a recurring issue of low enrollments across many civil engineering departments in postsecondary institutions. While there have been moments where enrollments begin to increase, civil engineering departments find themselves facing low enrollments at around 60% over the last five years across the Middle East. There are many reasons that could be attributed to this decline, such as low entry-level salaries, over-saturation of civil engineering graduates in the job market, and a lack of construction projects due to the impending or current recession. However, this recurring problem alludes to an intrinsic issue of the curriculum. The societal shift to the usage of high technology such as machine learning (ML) and artificial intelligence (AI) demands individuals who are proficient at utilizing it. Therefore, existing curriculums must adapt to this change in order to provide an education that is suitable for potential and current students. In this paper, In order to provide potential solutions for this issue, the analysis considers two possible implementations of high technology into the civil engineering curriculum. The first approach is to implement a course that introduces applications of high technology in Civil Engineering contexts. While the other approach is to intertwine applications of high technology throughout the degree. Both approaches, however, should meet requirements of accreditation agencies. In addition to the proposed improvement in civil engineering curriculum, a different pedagogical practice must be adapted as well. The passive learning approach might not be appropriate for Gen Z students; current students, now more than ever, need to be introduced to engineering topics and practice following different learning methods to ensure they will have the necessary skills for the job market. Different learning methods that incorporate high technology applications, like AI, must be integrated throughout the curriculum to make the civil engineering degree more attractive to prospective students. Moreover, the paper provides insight on the importance and approach of adapting the Civil Engineering curriculum to address the current low enrollment crisis that civil engineering departments globally, but specifically in the Middle East, are facing.

Keywords: artificial intelligence (AI), civil engineering curriculum, high technology, low enrollment, pedagogy

Procedia PDF Downloads 166
19852 Economical Analysis of Optimum Insulation Thickness for HVAC Duct

Authors: D. Kumar, S. Kumar, A. G. Memon, R. A. Memon, K. Harijan

Abstract:

A considerable amount of energy is usually lost due to compression of insulation in Heating, ventilation, and air conditioning (HVAC) duct. In this paper, the economic impact of compression of insulation is estimated. Relevant mathematical models were used to estimate the optimal thickness at the points of compression. Furthermore, the payback period is calculated for the optimal thickness at the critical parts of supply air duct (SAD) and return air duct (RAD) considering natural gas (NG) and liquefied petroleum gas (LPG) as fuels for chillier operation. The mathematical model is developed using preliminary data obtained for an HVAC system of a pharmaceutical company. The higher heat gain and cooling loss, due to compression of thermal insulation, is estimated using relevant heat transfer equations. The results reveal that maximum energy savings (ES) in SAD is 34.5 and 40%, while in RAD is 22.9% and 29% for NG and LPG, respectively. Moreover, the minimum payback period (PP) for SAD is 2 and 1.6years, while in RAD is 4.3 and 2.7years for NG and LPG, respectively. The optimum insulation thickness (OIT) corresponding to maximum ES and minimum PP is estimated to be 35 and 42mm for SAD, while 30 and 38mm for RAD in case of NG and LPG, respectively.

Keywords: optimum insulation thickness, life cycle cost analysis, payback period, HVAC system

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19851 Offline High Voltage Diagnostic Test Findings on 15MVA Generator of Basochhu Hydropower Plant

Authors: Suprit Pradhan, Tshering Yangzom

Abstract:

Even with availability of the modern day online insulation diagnostic technologies like partial discharge monitoring, the measurements like Dissipation Factor (tanδ), DC High Voltage Insulation Currents, Polarization Index (PI) and Insulation Resistance Measurements are still widely used as a diagnostic tools to assess the condition of stator insulation in hydro power plants. To evaluate the condition of stator winding insulation in one of the generators that have been operated since 1999, diagnostic tests were performed on the stator bars of 15 MVA generators of Basochhu Hydropower Plant. This paper presents diagnostic study done on the data gathered from the measurements which were performed in 2015 and 2016 as part of regular maintenance as since its commissioning no proper aging data were maintained. Measurement results of Dissipation Factor, DC High Potential tests and Polarization Index are discussed with regard to their effectiveness in assessing the ageing condition of the stator insulation. After a brief review of the theoretical background, the strengths of each diagnostic method in detecting symptoms of insulation deterioration are identified. The interesting results observed from Basochhu Hydropower Plant is taken into consideration to conclude that Polarization Index and DC High Voltage Insulation current measurements are best suited for the detection of humidity and contamination problems and Dissipation Factor measurement is a robust indicator of long-term ageing caused by oxidative degradation.

Keywords: dissipation Factor (tanδ), polarization Index (PI), DC High Voltage Insulation Current, insulation resistance (IR), Tan Delta Tip-Up, dielectric absorption ratio

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19850 Cultural and Natural Heritage Conservation by GIS Tourism Inventory System Project

Authors: Gamze Safak, Umut Arslanoglu

Abstract:

Cultural and tourism conservation and development zones and tourism centers are the boundaries declared for the purpose of protecting, using, and evaluating the sectoral development and planned development in areas where historical and cultural values are heavily involved and/or where tourism potential is high. The most rapidly changing regions in Turkey are tourism areas, especially the coastal areas. Planning these regions is not about only an economic gain but also a natural and physical environment and refers to a complex process. If the tourism sector is not well controlled, excessive use of natural resources and wrong location choices may cause damage to natural areas, historical values, and socio-cultural structure. Since the strategic decisions taken in the environmental order and zoning plans, which are the means of guiding the physical environment of the Ministry of Culture and Tourism, which have the authority to make plans in tourism centers, are transformed into plan decisions that find the spatial expression, comprehensive evaluation of all kinds of data, following the historical development and based on the correct and current data is required. In addition, the authority has a number of competences in tourism promotion as well as the authority to plan, leading to the necessity of taking part in the applications requiring complex analysis such as the management and integration of the country's economic, political, social and cultural resources. For this purpose, Tourism Inventory System (TES) project, which consists of a series of subsystems, has been developed in order to solve complex planning and method problems in the management of site-related information. The scope of the project is based on the integration of numerical and verbal data in the regions within the jurisdiction of the authority, and the monitoring of the historical development of urban planning studies, making the spatial data of the institution easily accessible, shared, questionable and traceable in international standards. A dynamic and continuous system design has been put into practice by utilizing the advantage of the use of Geographical Information Systems in the planning process to play a role in making the right decisions, revealing the tools of social, economic, cultural development, and preservation of natural and cultural values. This paper, which is prepared by the project team members in TES (Tourism Inventory System), will present a study regarding the applicability of GIS in cultural and natural heritage conservation.

Keywords: cultural conservation, GIS, geographic information system, tourism inventory system, urban planning

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19849 Lessons Learned from Ransomware-as-a-Service (RaaS) Organized Campaigns

Authors: Vitali Kremez

Abstract:

The researcher monitored an organized ransomware campaign in order to gain significant visibility into the tactics, techniques, and procedures employed by a campaign boss operating a ransomware scheme out of Russia. As the Russian hacking community lowered the access requirements for unsophisticated Russian cybercriminals to engage in ransomware campaigns, corporations and individuals face a commensurately greater challenge of effectively protecting their data and operations from being held ransom. This report discusses two notorious ransomware campaigns. Though the loss of data can be devastating, the findings demonstrate that sending ransom payments does not always help obtain data. Key learnings: 1. From the ransomware affiliate perspective, such campaigns have significantly lowered the barriers for entry for low-tier cybercriminals. 2. Ransomware revenue amounts are not as glamorous and fruitful as they are often publicly reported. Average ransomware crime bosses make only $90K per year on average. 3. Data gathered indicates that sending ransom payments does not always help obtain data. 4. The talk provides the complete payout structure and Bitcoin laundering operation related to the ransomware-as-a-service campaign.

Keywords: bitcoin, cybercrime, ransomware, Russia

Procedia PDF Downloads 195
19848 A Simulation of Land Market through Agent-Based Modeling

Authors: Zilin Zhang

Abstract:

Agent-based simulation has become a popular method of exploring the behavior of all kinds of urban systems. The city clearly is viewed as such a system. Many urban evolution processes, such as the development or the transaction of a piece of land, can be modeled with a set of rules. Such modeling approaches can be used to gain insight into urban-development and land market transactions in the real world. Our work contributes to such type of research by modeling the transactions of lands in a city and its surrounding suburbs. By replicating the demand and supply needs in the land market, we are able to demonstrate the different transaction patterns in three types of residential areas - downtown, city-suburban, and further suburban areas. In addition, we are also able to compare the vital roles of different activation conditions play in generating the various transaction patterns of the land market at the macro level. We use this simulation to loosely test our hypotheses about the nature of activation regimes by the replication of the Zi traders’ model. In the end, we hope our analytical results can be useful for city planners and policymakers to develop rational city plans and policies for shaping sustainable urban development.

Keywords: simulation, agent-based modeling, housing market, city

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19847 Black-Box-Optimization Approach for High Precision Multi-Axes Forward-Feed Design

Authors: Sebastian Kehne, Alexander Epple, Werner Herfs

Abstract:

A new method for optimal selection of components for multi-axes forward-feed drive systems is proposed in which the choice of motors, gear boxes and ball screw drives is optimized. Essential is here the synchronization of electrical and mechanical frequency behavior of all axes because even advanced controls (like H∞-controls) can only control a small part of the mechanical modes – namely only those of observable and controllable states whose value can be derived from the positions of extern linear length measurement systems and/or rotary encoders on the motor or gear box shafts. Further problems are the unknown processing forces like cutting forces in machine tools during normal operation which make the estimation and control via an observer even more difficult. To start with, the open source Modelica Feed Drive Library which was developed at the Laboratory for Machine Tools, and Production Engineering (WZL) is extended from one axis design to the multi axes design. It is capable to simulate the mechanical, electrical and thermal behavior of permanent magnet synchronous machines with inverters, different gear boxes and ball screw drives in a mechanical system. To keep the calculation time down analytical equations are used for field and torque producing equivalent circuit, heat dissipation and mechanical torque at the shaft. As a first step, a small machine tool with a working area of 635 x 315 x 420 mm is taken apart, and the mechanical transfer behavior is measured with an impulse hammer and acceleration sensors. With the frequency transfer functions, a mechanical finite element model is built up which is reduced with substructure coupling to a mass-damper system which models the most important modes of the axes. The model is modelled with Modelica Feed Drive Library and validated by further relative measurements between machine table and spindle holder with a piezo actor and acceleration sensors. In a next step, the choice of possible components in motor catalogues is limited by derived analytical formulas which are based on well-known metrics to gain effective power and torque of the components. The simulation in Modelica is run with different permanent magnet synchronous motors, gear boxes and ball screw drives from different suppliers. To speed up the optimization different black-box optimization methods (Surrogate-based, gradient-based and evolutionary) are tested on the case. The objective that was chosen is to minimize the integral of the deviations if a step is given on the position controls of the different axes. Small values are good measures for a high dynamic axes. In each iteration (evaluation of one set of components) the control variables are adjusted automatically to have an overshoot less than 1%. It is obtained that the order of the components in optimization problem has a deep impact on the speed of the black-box optimization. An approach to do efficient black-box optimization for multi-axes design is presented in the last part. The authors would like to thank the German Research Foundation DFG for financial support of the project “Optimierung des mechatronischen Entwurfs von mehrachsigen Antriebssystemen (HE 5386/14-1 | 6954/4-1)” (English: Optimization of the Mechatronic Design of Multi-Axes Drive Systems).

Keywords: ball screw drive design, discrete optimization, forward feed drives, gear box design, linear drives, machine tools, motor design, multi-axes design

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19846 Effects of Microbiological and Physicochemical Processes on the Quality of Complementary Foods Based on Maize (Zea mays) Fortification with Bambara Groundnut (Vigna subterranea)

Authors: T. I. Mbata, M. J. Ikenebomeh

Abstract:

Background: The study was aim at formulating a complementary foods based on maize and bambara groundnut with a view of reducing malnutrition in low income families. Protein-energy malnutrition is a major health challenge attributed to the inappropriate complementary feeding practices, low nutritional quality of traditional complementary foods and high cost of quality protein-based complementary foods. Methods: The blends 70% maize, 30% bambara groundnut were evaluated for proximate analyses, minerals, amino acids profile, and antinutritional factors, using proprietary formula (‘Nutrend’) as standard. Antinutritional factors, amino acids, microbiological properties and sensory attributes were determined using standard methods. Results; For Protein, the results were 15.0% for roasted bambara groundnut maize germinated flour (RBMGF), 13.80% for cooked bambara groundnut maize germinated flour (CBMGF), 15.18% for soaked bambara groundnut maize germinated flour (SBMGF); values for maize flour and nutrend had 10.4% and 23.21% respectively. With respect to energy value, RBMGF, CBMGF, SBMGF, maize flour and nutrend had 494.9, 327.58, 356.49, 366.8 and 467.2 kcal respectively. The percentages of total essential amino acids in the composition of the blends were 36.9%, 40.7% and 38.9% for CBMGF, SBMGF and RBMGF, respectively, non-essential amino acids contents were 63.1%, 59.3% and 61.1% for CBMGF, SBMGF and RBMGF respectively. The mineral content, that is, calcium, potassium, magnesium and sodium, of formulated samples were higher than those obtained for maize flour and Nutrend. The antinutrient composition of RBMGF and CBMGF were lower than of SBMGF. The rats fed with the control diet exhibited better growth performance such as feed intake (1527 g) and body weight gain (93.8 g). For the microbial status, microflora gradually changed from gram negative enteric bacteria, molds, lactic acid bacteria and yeast to be dominated by gram positive lactic acid bacteria (LAB) and yeasts. Yeasts and LAB growth counts in the complementary food varied between 4.44 and 7.36 log cfu/ml. LAB number increased from 5.40 to 7.36 log cfu/ml during fermentation. Yeasts increased from 4.44 to 5.60 log cfu/ml. Organoleptic evaluation revealed that the foods were well accepted. Conclusion: Based on the findings the application of bambara groundnut fortification to traditional foods can promote the nutritional quality of African maize - based traditional foods with acceptable rheological and cooking qualities.

Keywords: bambara groundnut, maize, fortification, complementary food

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19845 The Triple Nexus: Key Challenges in Shifting from Conceptualization to Operationalization of the Humanitarian-Development-Peacebuilding Nexus

Authors: Sarah M. Bolger

Abstract:

There is a clear recognition that humanitarian and development workers are operating more and more frequently in situations of protracted crises, with conflict and violence undermining long-term development efforts. First coined at the World Humanitarian Summit in 2016, the humanitarian-development-peacebuilding nexus – or 'Triple Nexus' - seeks to promote greater cooperation and policy and program coherence amongst organizations working within and across the nexus. However, despite the clear need for such an approach, the Triple Nexus has failed to gain much traction. This is largely due to the lack of conceptual clarity for actors on the ground and the disconnect between the theory of the Triple Nexus and what that means in practice. This paper seeks to identify the key challenges in shifting from the conceptual definition of the Triple Nexus and what that can look like, particularly for multi-mandated organizations, to the operationalization of the Triple Nexus approach. It adopts a case study approach, examining a selection of organizations and programs and their approaches to the Triple Nexus in order to extract key challenges and lessons learned. Finally, key recommendations are provided on how these challenges can be overcome, allowing for the operationalization of the Triple Nexus and ultimately for a more integrated and sustainable approach to humanitarian, development, and peacebuilding work.

Keywords: development, humanitarian, peacebuilding, triple nexus

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19844 Effectiveness of Geogebra Training Activities through Teams for Junior High School Teachers

Authors: Idha Novianti, Suci Nurhayati, Puryati, Elang Krisnadi

Abstract:

Community service activities are activities of the academic community in practicing and cultivating science, knowledge, and technology to advance the general welfare and educate the nation's life as described in the Higher Education Law. Training activities on the use of GeoGebra software are an option because GeoGebra software is software that is easy to operate and complete in the presentation of graphic design. The training activity was held for 3 hours online via teams and 3 hours offline. Involving 15 junior high school mathematics teachers located around south Tangerang. As a result, all teachers were satisfied with the activity, and they had additional new knowledge and skills to teach mathematics in the topic of geometry and algebra. The existence of new knowledge made the participants increase their confidence in developing mathematical science for students at school.

Keywords: geogebra, Ms. teams, junior high school teacher, mathematics

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19843 Coping Orientation of Academic Community in the Time of COVID-19 Pandemic: A Pilot Survey Study

Authors: Fereshteh Ahmadi, Önver Cetrez, Said Zandi, Sharareh Akhavan

Abstract:

In this paper, we have mapped the coping methods used to address the coronavirus pandemic by members of the academic community. We conducted an anonymous survey of a convenient sample of 674 faculty/staff members and students from September to December 2020. A modified version of the RCOPE scale was used for data collection. The results indicate that both religious and existential coping methods were used by respondents. The study also indicates that even though 71% of in-formants believed in God or another religious figure, 61% reported that they had tried to gain control of the situation directly without the help of God or another religious figure. The ranking of the coping strategies used indicates that the first five methods used by informants were all non-religious coping methods (i.e., secular existential coping methods): regarding life as a part of a greater whole, regarding nature as an important resource, listening to the sound of surrounding nature, being alone and con-templating, and walking/engaging in any activities outdoors giving a spiritual feeling. Our results contribute to the new area of research on academic community’s coping with pandemic-related stress and challenges.

Keywords: academic staff, academics, coping strategies, coronavirus epidemic, higher education.

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19842 Graphical Modeling of High Dimension Processes with an Environmental Application

Authors: Ali S. Gargoum

Abstract:

Graphical modeling plays an important role in providing efficient probability calculations in high dimensional problems (computational efficiency). In this paper, we address one of such problems where we discuss fragmenting puff models and some distributional assumptions concerning models for the instantaneous, emission readings and for the fragmenting process. A graphical representation in terms of a junction tree of the conditional probability breakdown of puffs and puff fragments is proposed.

Keywords: graphical models, influence diagrams, junction trees, Bayesian nets

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19841 Countering the Bullwhip Effect by Absorbing It Downstream in the Supply Chain

Authors: Geng Cui, Naoto Imura, Katsuhiro Nishinari, Takahiro Ezaki

Abstract:

The bullwhip effect, which refers to the amplification of demand variance as one moves up the supply chain, has been observed in various industries and extensively studied through analytic approaches. Existing methods to mitigate the bullwhip effect, such as decentralized demand information, vendor-managed inventory, and the Collaborative Planning, Forecasting, and Replenishment System, rely on the willingness and ability of supply chain participants to share their information. However, in practice, information sharing is often difficult to realize due to privacy concerns. The purpose of this study is to explore new ways to mitigate the bullwhip effect without the need for information sharing. This paper proposes a 'bullwhip absorption strategy' (BAS) to alleviate the bullwhip effect by absorbing it downstream in the supply chain. To achieve this, a two-stage supply chain system was employed, consisting of a single retailer and a single manufacturer. In each time period, the retailer receives an order generated according to an autoregressive process. Upon receiving the order, the retailer depletes the ordered amount, forecasts future demand based on past records, and places an order with the manufacturer using the order-up-to replenishment policy. The manufacturer follows a similar process. In essence, the mechanism of the model is similar to that of the beer game. The BAS is implemented at the retailer's level to counteract the bullwhip effect. This strategy requires the retailer to reduce the uncertainty in its orders, thereby absorbing the bullwhip effect downstream in the supply chain. The advantage of the BAS is that upstream participants can benefit from a reduced bullwhip effect. Although the retailer may incur additional costs, if the gain in the upstream segment can compensate for the retailer's loss, the entire supply chain will be better off. Two indicators, order variance and inventory variance, were used to quantify the bullwhip effect in relation to the strength of absorption. It was found that implementing the BAS at the retailer's level results in a reduction in both the retailer's and the manufacturer's order variances. However, when examining the impact on inventory variances, a trade-off relationship was observed. The manufacturer's inventory variance monotonically decreases with an increase in absorption strength, while the retailer's inventory variance does not always decrease as the absorption strength grows. This is especially true when the autoregression coefficient has a high value, causing the retailer's inventory variance to become a monotonically increasing function of the absorption strength. Finally, numerical simulations were conducted for verification, and the results were consistent with our theoretical analysis.

Keywords: bullwhip effect, supply chain management, inventory management, demand forecasting, order-to-up policy

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19840 Effects of Probiotic Pseudomonas fluorescens on the Growth Performance, Immune Modulation, and Histopathology of African Catfish (Clarias gariepinus)

Authors: Nelson R. Osungbemiro, O. A. Bello-Olusoji, M. Oladipupo

Abstract:

This study was carried out to determine the effects of probiotics Pseudomonas fluorescens on the growth performance, histology examination and immune modulation of African Catfish, (Clarias gariepinus) challenged with Clostridium botulinum. P. fluorescens, and C. botulinum isolates were removed from the gut, gill and skin organs of procured adult samples of Clarias gariepinus from commercial fish farms in Akure, Ondo State, Nigeria. The physical and biochemical tests were performed on the bacterial isolates using standard microbiological techniques for their identification. Antibacterial activity tests on P. fluorescens showed inhibition zone with mean value of 3.7 mm which indicates high level of antagonism. The experimental diets were prepared at different probiotics bacterial concentration comprises of five treatments of different bacterial suspension, including the control (T1), T2 (10³), T3 (10⁵), T4 (10⁷) and T5 (10⁹). Three replicates for each treatment type were prepared. Growth performance and nutrients utilization indices were calculated. The proximate analysis of fish carcass and experimental diet was carried out using standard methods. After feeding for 70 days, haematological values and histological test were done following standard methods; also a subgroup from each experimental treatment was challenged by inoculating Intraperitonieally (I/P) with different concentration of pathogenic C. botulinum. Statistically, there were significant differences (P < 0.05) in the growth performance and nutrient utilization of C. gariepinus. Best weight gain and feed conversion ratio were recorded in fish fed T4 (10⁷) and poorest value obtained in the control. Haematological analyses of C. gariepinus fed the experimental diets indicated that all the fish fed diets with P. fluorescens had marked significantly (p < 0.05) higher White Blood Cell than the control diet. The results of the challenge test showed that fish fed the control diet had the highest mortality rate. Histological examination of the gill, intestine, and liver of fish in this study showed several histopathological alterations in fish fed the control diets compared with those fed the P. fluorescens diets. The study indicated that the optimum level of P. fluorescens required for C. gariepinus growth and white blood cells formation is 10⁷ CFU g⁻¹, while carcass protein deposition required 10⁵ CFU g⁻¹ of P. fluorescens concentration. The study also confirmed P. fluorescens as efficient probiotics that is capable of improving the immune response of C. gariepinus against the attack of a virulent fish pathogen, C. botulinum.

Keywords: Clarias gariepinus, Clostridium botulinum, probiotics, Pseudomonas fluorescens

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19839 Social and Economic Impact of Home Sharing in Metro Manila: Hosts' Perspective

Authors: Ma. Karen Jimeno, Erika Kate Co, Ma. Claudia Alexis Frani, Shane Rosshel Guzman, Marie Jaye Constance Selga

Abstract:

Home sharing continues to gain traction in the Philippines at the expense of traditional lodging options, to which the hospitality industry has reacted in stages. This study aims to describe the social and economic impact of home sharing in Metro Manila from the perspective of hosts. A cross-sectional survey questionnaire consisting of five-point Likert items was administered to 120 hosts in Metro Manila. Kruskal-Wallis test, together with Dunn’s pairwise comparison, was used in the analysis of data. Results show that there is a significant difference in the median scores between increased awareness of Filipino food/heritage and the pursuit of enjoyable life in terms of social impact. Economic-wise, the respondents, did not perceive that their businesses as an additional source of income for the local government. These findings can be used for further exploratory studies and formulation of sustainable business policies conducive for the entrepreneurs and the hospitality industry alike.

Keywords: bed-and-breakfast, home sharing, marketing, tourism

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19838 A Multiple Beam LTE Base Station Antenna with Simultaneous Vertical and Horizontal Sectorization

Authors: Mohamed Sanad, Noha Hassan

Abstract:

A low wind-load light-weight broad-band multi-beam base station antenna has been developed. It can generate any required number of beams with the required beamwidths. It can have horizontal and vertical sectorization at the same time. Vertical sectorization doubles the overall number of beams. It will be very valuable in LTE-A and 5G. It can be used to serve vertically split inner and outer cells, which improves system performance. The intersection between the beams of the proposed multi-beam antenna can be controlled by optimizing the design parameters of the antenna. The gain at the points of intersection between the beams, the null filling and the overlap between the beams can all be modified. The proposed multi-beam base station antenna can cover an unlimited number of wireless applications, regardless of their frequency bands. It can simultaneously cover all, current and future, wireless technology generations such as 2G, 3G, 4G (LTE), --- etc. For example, in LTE, it covers the bands 450-470 MHz, 690-960 MHz, 1.4-2.7 GHz and 3.3-3.8 GHz. It has at least 2 ports for each band in each beam for ±45° polarizations. It can include up to 72 ports or even more, which could facilitate any further needed capacity expansions.

Keywords: base station antenna, multi-beam antenna, smart antenna, vertical sectorization

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19837 A Study on Weight-Reduction of Double Deck High-Speed Train Using Size Optimization Method

Authors: Jong-Yeon Kim, Kwang-Bok Shin, Tae-Hwan Ko

Abstract:

The purpose of this paper is to suggest a weight-reduction design method for the aluminum extrusion carbody structure of a double deck high-speed train using size optimization method. The size optimization method was used to optimize thicknesses of skin and rib of the aluminum extrusion for the carbody structure. Thicknesses of 1st underframe, 2nd underframe, solebar and roof frame were selected by design variables in order to conduct size optimization. The results of the size optimization analysis showed that the weight of the aluminum extrusion could be reduced by 0.61 tons (5.60%) compared to the weight of the original carbody structure.

Keywords: double deck high-speed train, size optimization, weigh-reduction, aluminum extrusion

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19836 Recrystallization Microstructure Studies of Cold-Rolled Ta0.5Nb0.5Hf0.5ZrTi1.5 Non-Equiatomic Refractory High Entropy Alloy

Authors: Veeresham Mokali

Abstract:

Recrystallization microstructure and grain growth studies of Ta₀.₅Nb₀.₅Hf₀.₅ZrTi₁.₅ refractory high entropy alloy have been explored in the present work. The as-cast Ta₀.₅Nb₀.₅Hf₀.₅ZrTi₁.₅ alloy was cold-rolled to 90% in several passes at room temperature and further subjected to annealing treatment for recrystallization at 800°C, 1000°C, 1250°C, and 1400°C temperatures for one hour. However, the characterization of heavily cold-rolled and annealed condition specimens was done using scanning electron microscopy (SEM-EBSD). The cold-rolled specimens showed the development of an inhomogeneous microstructure. Upon annealing, recrystallized microstructures were achieved; in addition to that, the coarsening of microstructure with raising annealing temperature noticed in the range of 800°C – 1400°C annealed temperatures.

Keywords: refractory high entropy alloys, cold-rolling, recrystallization, microstructure

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19835 Investigating the Application of Social Sustainability: A Case Study in the Egyptian Retailing Sector

Authors: Lobna Hafez, Eman Elakkad

Abstract:

Sustainability is no longer a choice for firms. To achieve sustainable supply chain, all three dimensions of sustainability should be considered. Unlike the economic and environmental aspects, social sustainability has been rarely given attention. The problem surrounding social sustainability and employees’ welfare in Egypt is complex and remains unsolved. The aim of this study is to qualitatively assess the current level of application of social sustainability in the retailing sector in Egypt through using the social sustainability indicators identified in the literature. The purpose of this investigation is to gain knowledge about the complexity of the system involved. A case study is conducted on one of the largest retailers in Egypt. Data were collected through semi-structured interviews with managers and employees to determine the level of application and identify the major obstacles affecting the social sustainability in the retailing context. The work developed gives insights about the details and complexities of the application of social sustainability in developing countries, from the retailing perspective. The outcomes of this study will help managers to understand the enablers of social sustainability and will direct them to methods of sound implementation.

Keywords: developing countries, Egyptian retailing sector, sustainability, social sustainability

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19834 Date Palm Compreg: A High Quality Bio-Composite of Date Palm Wood

Authors: Mojtaba Soltani, Edi Suhaimi Bakar, Hamid Reza Naji

Abstract:

Date Palm Wood (D.P.W) specimens were impregnated with Phenol formaldehyde (PF) resin at 15% level, using vacuum/pressure method. Three levels of moisture content (MC) (50%, 60%, and 70% ) before pressing stage and three hot pressing times (15, 20, and 30 minutes) were the variables. The boards were prepared at 20% compression rate. The physical properties of specimens such as spring back, thickness swelling and water absorption, and mechanical properties including MOR, MOE were studied and compared between variables. The results indicated that the percentage of MC levels before compression set was the main factor on the properties of the Date Palm Compreg. Also, the results showed that this compregnation method can be used as a good method for making high-quality bio-composite from Date Palm Wood.

Keywords: Date palm, phenol formaldehyde resin, high-quality bio-composite, physical and mechanical properties

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19833 Assessing the Factors Mediating the Attitude-Behaviour Gap in Sustainable Fashion Consumerism

Authors: A. Bardey, P. James

Abstract:

With the rise of fast-fashion, over consumerism and overproduction, the fashion industry is believed to be one of the most polluting industry. It is a matter of importance today to further understand the factors involved in green consumerism to enhance sustainable fashion. One of the critical issues in also evaluating green consumerism, particularly in fashion, is the attitude-behaviour gap. Indeed, many consumers report a positive attitude towards sustainable fashion consumerism, but this attitude is not always actioned into behaviour. This study aims to further investigate the attitude-behaviour gap in sustainable fashion consumerism. S triangulation of qualitative and quantitative methods was used. Focus groups were used to gain opinions and understanding of the barriers to sustainable fashion consumption. A quantitative online questionnaire was then used to quantify the barriers identified in Study 1 and measure their influence on the attitude-behaviour gap. The results suggest that knowledge about sustainable fashion is the key factor in the attitude-behaviour gap in sustainable fashion consumerism. Accessibility was also identified as a factor, but this relationship is more complex. It is suggested that knowledge is the main factor in the attitude-behaviour gap and that once knowledge is controlled for, accessibility will become a main factor. The present study is the first one to identify the factors involved in sustainable fashion consumerism.

Keywords: fashion, consumer behaviour, sustainable consumerism, attitude-behavioural gap

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19832 The Potentials of Online Learning and the Challenges towards Its Adoption in Nigeria's Higher Institutions of Learning

Authors: Kuliya Muhammed

Abstract:

This paper examines the potentials of online learning and the challenges to its adoption in Nigeria’s higher institutions of learning. The research would assist in tackling the challenges of online learning adoption and enlighten institutions on the numerous benefits of online learning in Nigeria. The researcher used survey method for the study and questionnaires were used to obtain the needed data from 230 respondents cut across 20 higher institutions in the country. The findings revealed that online learning has the prospect to boost access to learning tools, assist students’ to learn from the comfort of their offices or homes, reduce the cost of learning, and enable individuals to gain self-knowledge. The major challenges in the adoption of e-learning are poor Information and Communication Technology infrastructures, poor internet connectivity where available, lack of Information and Communication Technology background, problem of power supply, lack of commitment by institutions, poor maintenance of Information and Communication Technology tools, inadequate facilities, lack of government funding and fraud. Recommendations were also made at the end of the research work.

Keywords: electronic, ICT, institution, internet, learning, technology

Procedia PDF Downloads 388
19831 Finite Element Analysis of High Performance Synchronous Reluctance Machines

Authors: T. Mohanarajah, J. Rizk, M. Nagrial, A. Hellany

Abstract:

This paper analyses numerous features of the synchronous Reluctance Motor (Syn-RM) and propose a rotor for high electrical torque, power factor & efficiency using Finite Element Method (FEM). A comprehensive analysis completed on solid rotor structure while the total thickness of the flux guide kept constant. A number of tests carried out for nine different studies to find out optimum location of the flux guide, the optimum location of multiple flux guides & optimum wall thickness between flux guides for high-performance reluctance machines. The results are concluded with the aid of FEM simulation results, the saliency ratio and machine characteristics (location, a number of barriers & wall width) analysed.

Keywords: electrical machines, finite element method, synchronous reluctance machines, variable reluctance machines

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19830 Consumer Market of Agricultural Products and Agricultural Policy in Georgia

Authors: G. Erkomaishvili, M. Kobalava, T. Lazariashvili, M. Saghareishvili

Abstract:

The article discusses the consumer market of agricultural products and agricultural policy in Georgia. It is noted that development of the strategic areas of the agricultural sector needs a special support. These strategic areas should create the country's major export potential. It is important to develop strategies to access to the international markets, form extensive marketing network etc., which will become the basis for the promotion and revenue growth of the country. The Georgian agricultural sector, with the right state policy and support, can achieve success and gain access to the world market with competitive agricultural products. The paper discusses the current condition of agriculture, export and import of agricultural products and agricultural policy in Georgia. The conducted research concludes the information that there is an increasing demand on the green goods in the world market. Natural and climatic conditions of Georgia give a serious possibility of implementing it. The research presents an agricultural development strategy in Georgia and the findings and based on them recommendations are proposed.

Keywords: agriculture, export-import of agricultural products, agricultural cooperative society, agricultural policy, agricultural insurance

Procedia PDF Downloads 319
19829 Comprehensive Experimental Study to Determine Energy Dissipation of Nappe Flows on Stepped Chutes

Authors: Abdollah Ghasempour, Mohammad Reza Kavianpour, Majid Galoie

Abstract:

This study has investigated the fundamental parameters which have effective role on energy dissipation of nappe flows on stepped chutes in order to estimate an empirical relationship using dimensional analysis. To gain this goal, comprehensive experimental study on some large-scale physical models with various step geometries, slopes, discharges, etc. were carried out. For all models, hydraulic parameters such as velocity, pressure, water depth, flow regime and etc. were measured precisely. The effective parameters, then, could be determined by analysis of experimental data. Finally, a dimensional analysis was done in order to estimate an empirical relationship for evaluation of energy dissipation of nappe flows on stepped chutes. Because of using the large-scale physical models in this study, the empirical relationship is in very good agreement with the experimental results.

Keywords: nappe flow, energy dissipation, stepped chute, dimensional analysis

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19828 Computer-Based versus Paper-Based Tests: A Comparative Study of Two Types of Indonesian National Examination for Senior High School Students

Authors: Faizal Mansyur

Abstract:

The objective of this research is to find out whether there is a significant difference in the English language scores of senior high school students in the Indonesia National Examination for students tested by using computer-based and paper-based tests. The population of this research is senior high school students in South Sulawesi Province who sat the Indonesian National Examination for 2015/2016 academic year. The samples of this research are 800 students’ scores from 8 schools taken by employing the multistage random sampling technique. The data of this research is a secondary data since it is obtained from the education office for South Sulawesi. In analyzing the collected data, the researcher employed the independent samples T-Test with the help of SPSS v.24 program. The finding of this research reveals that there is a significant difference in the English language scores of senior high school students in the Indonesia National Examination for students tested by using computer-based and paper-based Tests (p < .05). Moreover, students tested by using PBT (Mean = 63.13, SD = 13.63) achieve higher score than those tested by using CBT (Mean = 46.33, SD = 14.68).

Keywords: computer-based test, paper-based test, Indonesian national examination, testing

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19827 An International Analysis of Career Development and Management Programs for High-Performance Athletes: A Perspective of Organizational Support

Authors: H. J. Hong

Abstract:

Sporting organizations are arguably responsible for encouraging high-performance athletes to balance their life and identity during their sporting career; sporting organizations can establish the motivational climate for high-performance athletes using athlete career development and management programs. The purpose of this article to provide an overview of career development and management programs in 20 countries and to examine the following seven features of the programs: (1) Which government-funded sporting organizations provide career development and management programs? (2) Which athletes are eligible to access the programs? (3) What are the aims and objectives of the programs? (4) What are the activities and content of the programs? (5) Who is responsible for the delivery of the programs within organizations (e.g., advisors, coordinators, service providers, counsellors, etc.)? (6) Do the sporting organizations have training and development programs for support services providers? and (7) Do the sporting organizations assess the programs in terms of the programs’ impact on high-performance athletes’ career development and management skills? Web-based data collection was conducted first. The author contacted the sporting organizations to clarify information as required by requesting further information via emails, international calls, video calls on Skype, and by visiting the sporting organizations and meeting with the practitioners (Fiji, Ireland, Korea, Scotland, Singapore, and Spain). By selecting comparable career development and management programs, the present study reviews programs across the world, identifying similarities, differences, and difficulties, so that sporting organizations and practitioners may enhance the quality of their programs. Since international comparisons of career development and management programs remain scarce, the findings deepen the knowledge of high-performance athletes’ career development, management, and transitions in the areas of organizational support programs.

Keywords: athletes' career development and management, athletes' psychological preparation, organizational support, sport career transition

Procedia PDF Downloads 125