Search results for: OBMI (oil base mud imager)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2098

Search results for: OBMI (oil base mud imager)

1618 A Broadband Tri-Cantilever Vibration Energy Harvester with Magnetic Oscillator

Authors: Xiaobo Rui, Zhoumo Zeng, Yibo Li

Abstract:

A novel tri-cantilever energy harvester with magnetic oscillator was presented, which could convert the ambient vibration into electrical energy to power the low-power devices such as wireless sensor networks. The most common way to harvest vibration energy is based on the use of linear resonant devices such as cantilever beam, since this structure creates the highest strain for a given force. The highest efficiency will be achieved when the resonance frequency of the harvester matches the vibration frequency. The limitation of the structure is the narrow effective bandwidth. To overcome this limitation, this article introduces a broadband tri-cantilever harvester with nonlinear stiffness. This energy harvester typically consists of three thin cantilever beams vertically arranged with Neodymium Magnets ( NdFeB)magnetics at its free end and a fixed base at the other end. The three cantilevers have different resonant frequencies by designed in different thicknesses. It is obviously that a similar advantage of multiple resonant frequencies as piezoelectric cantilevers array structure is built. To achieve broadband energy harvesting, magnetic interaction is used to introduce the nonlinear system stiffness to tune the resonant frequency to match the excitation. Since the three cantilever tips are all free and the magnetic force is distance dependent, the resonant frequencies will be complexly changed with the vertical vibration of the free end. Both model and experiment are built. The electromechanically coupled lumped-parameter model is presented. An electromechanical formulation and analytical expressions for the coupled nonlinear vibration response and voltage response are given. The entire structure is fabricated and mechanically attached to a electromagnetic shaker as a vibrating body via the fixed base, in order to couple the vibrations to the cantilever. The cantilevers are bonded with piezoelectric macro-fiber composite (MFC) materials (Model: M8514P2). The size of the cantilevers is 120*20mm2 and the thicknesses are separately 1mm, 0.8mm, 0.6mm. The prototype generator has a measured performance of 160.98 mW effective electrical power and 7.93 DC output voltage via the excitation level of 10m/s2. The 130% increase in the operating bandwidth is achieved. This device is promising to support low-power devices, peer-to-peer wireless nodes, and small-scale wireless sensor networks in ambient vibration environment.

Keywords: tri-cantilever, ambient vibration, energy harvesting, magnetic oscillator

Procedia PDF Downloads 154
1617 Development and Range Testing of a LoRaWAN System in an Urban Environment

Authors: N. R. Harris, J. Curry

Abstract:

This paper describes the construction and operation of an experimental LoRaWAN network surrounding the University of Southampton in the United Kingdom. Following successful installation, an experimental node design is built and characterised, with particular emphasis on radio range. Several configurations are investigated, including different data rates, and varying heights of node. It is concluded that although range can be great (over 8 km in this case), environmental topology is critical. However, shorter range implementations, up to about 2 km in an urban environment, are relatively insensitive although care is still needed. The example node and the relatively simple base station reported demonstrate that LoraWan can be a very low cost and practical solution to Internet of Things type applications for distributed monitoring systems with sensors spread over distances of several km.

Keywords: long-range, wireless, sensor, network

Procedia PDF Downloads 137
1616 A Low Profile Dual Polarized Slot Coupled Patch Antenna

Authors: Mingde Du, Dong Han

Abstract:

A low profile, dual polarized, slot coupled patch antenna is designed and developed in this paper. The antenna has a measured bandwidth of 17.2% for return loss > 15 dB and pair ports isolation >23 dB. The gain of the antenna is over 10 dBi and the half power beam widths (HPBW) of the antenna are 80±3o in the horizontal plane and 39±2o in the vertical plane. The cross polarization discrimination (XPD) is less than 20 dB in HPBW. Within the operating band, the performances of good impedance match, high ports isolation, low cross polarization, and stable radiation patterns are achieved.

Keywords: dual polarized, patch antenna, slot coupled, base station antenna

Procedia PDF Downloads 462
1615 Top-K Shortest Distance as a Similarity Measure

Authors: Andrey Lebedev, Ilya Dmitrenok, JooYoung Lee, Leonard Johard

Abstract:

Top-k shortest path routing problem is an extension of finding the shortest path in a given network. Shortest path is one of the most essential measures as it reveals the relations between two nodes in a network. However, in many real world networks, whose diameters are small, top-k shortest path is more interesting as it contains more information about the network topology. Many variations to compute top-k shortest paths have been studied. In this paper, we apply an efficient top-k shortest distance routing algorithm to the link prediction problem and test its efficacy. We compare the results with other base line and state-of-the-art methods as well as with the shortest path. Then, we also propose a top-k distance based graph matching algorithm.

Keywords: graph matching, link prediction, shortest path, similarity

Procedia PDF Downloads 358
1614 SFO-ECRSEP: Sensor Field Optimızation Based Ecrsep For Heterogeneous WSNS

Authors: Gagandeep Singh

Abstract:

The sensor field optimization is a serious issue in WSNs and has been ignored by many researchers. As in numerous real-time sensing fields the sensor nodes on the corners i.e. on the segment boundaries will become lifeless early because no extraordinary safety is presented for them. Accordingly, in this research work the central objective is on the segment based optimization by separating the sensor field between advance and normal segments. The inspiration at the back this sensor field optimization is to extend the time spam when the first sensor node dies. For the reason that in normal sensor nodes which were exist on the borders may become lifeless early because the space among them and the base station is more so they consume more power so at last will become lifeless soon.

Keywords: WSNs, ECRSEP, SEP, field optimization, energy

Procedia PDF Downloads 300
1613 A Long Tail Study of eWOM Communities

Authors: M. Olmedilla, M. R. Martinez-Torres, S. L. Toral

Abstract:

Electronic Word-Of-Mouth (eWOM) communities represent today an important source of information in which more and more customers base their purchasing decisions. They include thousands of reviews concerning very different products and services posted by many individuals geographically distributed all over the world. Due to their massive audience, eWOM communities can help users to find the product they are looking for even if they are less popular or rare. This is known as the long tail effect, which leads to a larger number of lower-selling niche products. This paper analyzes the long tail effect in a well-known eWOM community and defines a tool for finding niche products unavailable through conventional channels.

Keywords: eWOM, online user reviews, long tail theory, product categorization, social network analysis

Procedia PDF Downloads 421
1612 An Enhanced Room Temperature Magnetic Refrigerator Based on Nanofluid: From Theoretical Study to Design

Authors: Moulay Youssef El Hafidi

Abstract:

In this research, an enhanced room-temperature magnetic refrigerator based on nanofluid, consisting of permanent magnets as a magnetism source, gadolinium as magnetocaloric material, water as base liquid, and carbon nanotubes (CNT) as nanoparticles, has been designed. The magnetic field is supplied by NdFeB permanent magnets and is about 1.3 Tesla. Two similar heat exchangers are employed to absorb and expel heat. The cycle performance of this self-designed device is analyzed theoretically. The results provide useful data for future optimization of room-temperature magnetic refrigeration using nanofluids.

Keywords: magnetic cooling, nanofluid, gadolinium, permanent magnets, heat exchange

Procedia PDF Downloads 82
1611 Real-Time Aerial Marine Surveillance System for Safe Navigation

Authors: Vinesh Thiruchelvam, Umar Mumtaz Chowdry, Sathish Kumar Selvaperumal

Abstract:

The prime purpose of the project is to provide a sophisticated system for surveillance specialized for the Port Authorities in the Maritime Industry. The current aerial surveillance does not have a wide dimensioning view. The channels of communication is shared and not exclusive allowing for communications errors or disturbance mainly due to traffic. The scope is to analyze the various aspects as real-time aerial and marine surveillance is one of the most important methods which could ensure the domain security of the sailors. The system will improve real time data as obtained for the controller base station. The key implementation will be based on camera speed, angle and adherence to a sustainable power utilization module.

Keywords: SMS, real time, GUI, maritime industry

Procedia PDF Downloads 498
1610 Bamboo Fibre Extraction and Its Reinforced Polymer Composite Material

Authors: P. Zakikhani, R. Zahari, M. T. H. Sultan, D. L. Majid

Abstract:

Natural plant fibres reinforced polymeric composite materials have been used in many fields of our lives to save the environment. Especially, bamboo fibres due to its environmental sustainability, mechanical properties, and recyclability have been utilized as reinforced polymer matrix composite in construction industries. In this review study bamboo structure and three different methods such as mechanical, chemical and combination of mechanical and chemical to extract fibres from bamboo are summarized. Each extraction method has been done base on the application of bamboo. In addition Bamboo fibre is compared with glass fibre from various aspects and in some parts it has advantages over the glass fibre.

Keywords: bamboo fibres, natural fibres, bio composite, mechanical extraction, glass fibres

Procedia PDF Downloads 490
1609 Comparative Study of Scheduling Algorithms for LTE Networks

Authors: Samia Dardouri, Ridha Bouallegue

Abstract:

Scheduling is the process of dynamically allocating physical resources to User Equipment (UE) based on scheduling algorithms implemented at the LTE base station. Various algorithms have been proposed by network researchers as the implementation of scheduling algorithm which represents an open issue in Long Term Evolution (LTE) standard. This paper makes an attempt to study and compare the performance of PF, MLWDF and EXP/PF scheduling algorithms. The evaluation is considered for a single cell with interference scenario for different flows such as Best effort, Video and VoIP in a pedestrian and vehicular environment using the LTE-Sim network simulator. The comparative study is conducted in terms of system throughput, fairness index, delay, packet loss ratio (PLR) and total cell spectral efficiency.

Keywords: LTE, multimedia flows, scheduling algorithms, mobile computing

Procedia PDF Downloads 383
1608 COVID-19 Teaches Probability Risk Assessment

Authors: Sean Sloan

Abstract:

Probability Risk Assessments (PRA) can be a difficult concept for students to grasp. So in searching for different ways to describe PRA to relate it to their lives; COVID-19 came up. The parallels are amazing. Soon students began analyzing acceptable risk with the virus. This helped them to quantify just how dangerous is dangerous. The original lesson was dismissed and for the remainder of the period, the probability of risk, and the lethality of risk became the topic. Spreading events such as a COVID carrier on an airline became analogous to single fault casualties such as a Tsunami. Odds of spreading became odds of backup-diesel-generator failure – like with Fukashima Daiichi. Fatalities of the disease became expected fatalities due to radiation spread. Quantification from this discussion took it from hyperbole and emotion into one where we could rationally base guidelines. It has been one of the most effective educational devices observed.

Keywords: COVID, education, probability, risk

Procedia PDF Downloads 152
1607 Investigation of Fusion Zone Microstructures in Plasma Arc Welding of Austenitic Stainless Steel (SS-304L) with Low Carbon Steel (A-36) with or without Filler Alloy

Authors: Shan-e-Fatima, Mushtaq Khan, Syed Imran Hussian

Abstract:

Plasma arc welding technology is used for welding SS-304L with A-36. Two different optimize butt welded joints were produced by using austenitic filler alloy E-309L and with direct fusion at 45 A, 2mm/sec by keeping plasma gas flow rate at 0.5LPM. Microstructure analysis of the weld bead was carried out. The results reveal complex heterogeneous microstructure in austenitic base filler alloy sample where as full martensite was found in directly fused sample.

Keywords: fusion zone microstructure, stainless steel, low carbon steel, plasma arc welding

Procedia PDF Downloads 575
1606 Efficient Broadcasting in Wireless Sensor Networks

Authors: Min Kyung An, Hyuk Cho

Abstract:

In this paper, we study the Minimum Latency Broadcast Scheduling (MLBS) problem in wireless sensor networks (WSNs). The main issue of the MLBS problem is to compute schedules with the minimum number of timeslots such that a base station can broadcast data to all other sensor nodes with no collisions. Unlike existing works that utilize the traditional omni-directional WSNs, we target the directional WSNs where nodes can collaboratively determine and orientate their antenna directions. We first develop a 7-approximation algorithm, adopting directional WSNs. Our ratio is currently the best, to the best of our knowledge. We then validate the performance of the proposed algorithm through simulation.

Keywords: broadcast, collision-free, directional antenna, approximation, wireless sensor networks

Procedia PDF Downloads 346
1605 A Framework for Embedding Industry 4.0 in the UAE Defence Manufacturing Industry

Authors: Khalifa Al Baloushi, Hongwei Zhang, Terrence Perera

Abstract:

Over the last few decades, the government of the UAE has been taking actions to consolidate defense manufacturing entities with the view to build a coherent and modern defense manufacturing base. Whilst these actions have significantly improved the overall capabilities of defense manufacturing; further opportunities exist to radically transform the sector. A comprehensive literature review and data collected from a survey identified three potential areas of improvements, (a) integration of Industry 4.0 technologies and other smart technologies, (b) stronger engagement of small and Medium-sized defense manufacturing companies and (c) Enhancing the national defense policies by embedding best practices from other nations. This research paper presents the design and development of a conceptual framework for the UAE defense industrial ecosystem.

Keywords: industry 4.0, defense manufacturing, eco-systems, integration

Procedia PDF Downloads 207
1604 Tuning the Surface Roughness of Patterned Nanocellulose Films: An Alternative to Plastic Based Substrates for Circuit Priniting in High-Performance Electronics

Authors: Kunal Bhardwaj, Christine Browne

Abstract:

With the increase in global awareness of the environmental impacts of plastic-based products, there has been a massive drive to reduce our use of these products. Use of plastic-based substrates in electronic circuits has been a matter of concern recently. Plastics provide a very smooth and cheap surface for printing high-performance electronics due to their non-permeability to ink and easy mouldability. In this research, we explore the use of nano cellulose (NC) films in electronics as they provide an advantage of being 100% recyclable and eco-friendly. The main hindrance in the mass adoption of NC film as a substitute for plastic is its higher surface roughness which leads to ink penetration, and dispersion in the channels on the film. This research was conducted to tune the RMS roughness of NC films to a range where they can replace plastics in electronics(310-470nm). We studied the dependence of the surface roughness of the NC film on the following tunable aspects: 1) composition by weight of the NC suspension that is sprayed on a silicon wafer 2) the width and the depth of the channels on the silicon wafer used as a base. Various silicon wafers with channel depths ranging from 6 to 18 um and channel widths ranging from 5 to 500um were used as a base. Spray coating method for NC film production was used and two solutions namely, 1.5wt% NC and a 50-50 NC-CNC (cellulose nanocrystal) mixture in distilled water, were sprayed through a Wagner sprayer system model 117 at an angle of 90 degrees. The silicon wafer was kept on a conveyor moving at a velocity of 1.3+-0.1 cm/sec. Once the suspension was uniformly sprayed, the mould was left to dry in an oven at 50°C overnight. The images of the films were taken with the help of an optical profilometer, Olympus OLS 5000. These images were converted into a ‘.lext’ format and analyzed using Gwyddion, a data and image analysis software. Lowest measured RMS roughness of 291nm was with a 50-50 CNC-NC mixture, sprayed on a silicon wafer with a channel width of 5 µm and a channel depth of 12 µm. Surface roughness values of 320+-17nm were achieved at lower (5 to 10 µm) channel widths on a silicon wafer. This research opened the possibility of the usage of 100% recyclable NC films with an additive (50% CNC) in high-performance electronics. Possibility of using additives like Carboxymethyl Cellulose (CMC) is also being explored due to the hypothesis that CMC would reduce friction amongst fibers, which in turn would lead to better conformations amongst the NC fibers. CMC addition would thus be able to help tune the surface roughness of the NC film to an even greater extent in future.

Keywords: nano cellulose films, electronic circuits, nanocrystals and surface roughness

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1603 Applications of Social Marketing in Road Safety of Georgia

Authors: Charita Jashi

Abstract:

The aim of the paper is to explore the role of social marketing in changing the behavior of consumers on road safety, identify critical aspects and priority needs which impede the implementation of road safety program in Georgia. Given the goals of the study, a quantitative method was used to carry out interviews for primary data collection. This research identified the awareness level of road safety, legislation base, and marketing interventions to change behavior of drivers and pedestrians. During several years the non-governmental sector together with the local authorities and media have been very intensively working on the road safety issue in Georgia, but only seat-belts campaign should be considered rather successful. Despite achievements in this field, efficiency of road safety programs far from fulfillment and needs strong empowering.

Keywords: road safety, social marketing interventions, behavior change, well-being

Procedia PDF Downloads 201
1602 The Effect of Styrene-Butadiene-Rubber (SBR) Polymer Modifier on Properties of Bitumen

Authors: Seyed Abbas Tabatabaei, Alireza Kiasat, Ferdows Karimi Alkouhi

Abstract:

In order to use bitumen in hot mix asphalt, it must have specific characteristics. There are some methods to reach these properties. Using polymer modifiers are one of the methods to modify the bitumen properties. In this paper, the effect of Styrene-Butadiene-Rubber that is one of the bitumen polymer modifiers on rheology properties of bitumen is studied. In this regard, the rheological properties of base bitumen and the modified bitumen with 3, 4, and 5 percent of Styrene-Butadiene-Rubber (SBR) were analysed. The results show that bitumen modified with 5 percent of SBR has the best performance than the other samples.

Keywords: bitumen, polymer modifier, styrene-butadiene-rubber, rheological properties

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1601 Corrosion Analysis of a 3-1/2” Production Tubing of an Offshore Oil and Gas Well

Authors: Suraj Makkar, Asis Isor, Jeetendra Gupta, Simran Bareja, Maushumi K. Talukdar

Abstract:

During the exploratory testing phase of an offshore oil and gas well, when the tubing string was pulled out after production testing, it was observed that there was visible corrosion/pitting in a few of the 3-1/2” API 5 CT L-80 Grade tubing. The area of corrosion was at the same location in all the tubing, i.e., just above the pin end. Since the corrosion was observed in the tubing within two months of their installation, it was a matter of concern, as it could lead to premature failures resulting in leakages and production loss and thus affecting the integrity of the asset. Therefore, the tubing was analysed to ascertain the mechanism of the corrosion occurring on its surface. During the visual inspection, it was observed that the corrosion was totally external, which was near the pin end, and no significant internal corrosion was observed. The chemical compositional analysis and mechanical properties (tensile and impact) show that the pipeline material was conforming to API 5 CT L-80 specifications. The metallographic analysis of the tubing revealed tempered martensitic microstructure. The grain size was observed to be different at the pin end as compared to the microstructure at base metal. The microstructures of the corroded area near threads reveal an oriented microstructure. The clearly oriented microstructure of the cold-worked zone near threads and the difference in microstructure represents inappropriate heat treatment after cold work. This was substantiated by hardness test results as well, which show higher hardness at the pin end in comparison to hardness at base metal. Scanning Electron Microscope (SEM) analysis revealed the presence of round and deep pits and cracks on the corroded surface of the tubing. The cracks were stress corrosion cracks in a corrosive environment arising out of the residual stress, which was not relieved after cold working, as mentioned above. Energy Dispersive Spectroscopy (EDS) analysis indicates the presence of mainly Fe₂O₃, Chlorides, Sulphides, and Silica in the corroded part indicating the interaction of the tubing with the well completion fluid and well bore environment. Thus it was concluded that residual stress after the cold working of male pins during threading and the corrosive environment acted in synergy to cause this pitting corrosion attack on the highly stressed zone along the circumference of the tubing just below the threaded area. Accordingly, the following suitable recommendations were given to avoid the recurrence of such corrosion problems in the wells. (i) After any kind of hot work/cold work, tubing should be normalized at full length to achieve uniform microstructure throughout its length. (ii) Heat treatment requirements (as per API 5 CT) should be part of technical specifications while at the procurement stage.

Keywords: pin end, microstructure, grain size, stress corrosion cracks

Procedia PDF Downloads 80
1600 Heat Transfer Performance of a Small Cold Plate with Uni-Directional Porous Copper for Cooling Power Electronics

Authors: K. Yuki, R. Tsuji, K. Takai, S. Aramaki, R. Kibushi, N. Unno, K. Suzuki

Abstract:

A small cold plate with uni-directional porous copper is proposed for cooling power electronics such as an on-vehicle inverter with the heat generation of approximately 500 W/cm2. The uni-directional porous copper with the pore perpendicularly orienting the heat transfer surface is soldered to a grooved heat transfer surface. This structure enables the cooling liquid to evaporate in the pore of the porous copper and then the vapor to discharge through the grooves. In order to minimize the cold plate, a double flow channel concept is introduced for the design of the cold plate. The cold plate consists of a base plate, a spacer, and a vapor discharging plate, totally 12 mm in thickness. The base plate has multiple nozzles of 1.0 mm in diameter for the liquid supply and 4 slits of 2.0 mm in width for vapor discharging, and is attached onto the top surface of the porous copper plate of 20 mm in diameter and 5.0 mm in thickness. The pore size is 0.36 mm and the porosity is 36 %. The cooling liquid flows into the porous copper as an impinging jet flow from the multiple nozzles, and then the vapor, which is generated in the pore, is discharged through the grooves and the vapor slits outside the cold plate. A heated test section consists of the cold plate, which was explained above, and a heat transfer copper block with 6 cartridge heaters. The cross section of the heat transfer block is reduced in order to increase the heat flux. The top surface of the block is the grooved heat transfer surface of 10 mm in diameter at which the porous copper is soldered. The grooves are fabricated like latticework, and the width and depth are 1.0 mm and 0.5 mm, respectively. By embedding three thermocouples in the cylindrical part of the heat transfer block, the temperature of the heat transfer surface ant the heat flux are extrapolated in a steady state. In this experiment, the flow rate is 0.5 L/min and the flow velocity at each nozzle is 0.27 m/s. The liquid inlet temperature is 60 °C. The experimental results prove that, in a single-phase heat transfer regime, the heat transfer performance of the cold plate with the uni-directional porous copper is 2.1 times higher than that without the porous copper, though the pressure loss with the porous copper also becomes higher than that without the porous copper. As to the two-phase heat transfer regime, the critical heat flux increases by approximately 35% by introducing the uni-directional porous copper, compared with the CHF of the multiple impinging jet flow. In addition, we confirmed that these heat transfer data was much higher than that of the ordinary single impinging jet flow. These heat transfer data prove high potential of the cold plate with the uni-directional porous copper from the view point of not only the heat transfer performance but also energy saving.

Keywords: cooling, cold plate, uni-porous media, heat transfer

Procedia PDF Downloads 295
1599 A Review on Applications of Experts Systems in Medical Sciences

Authors: D. K. Sreekantha, T. M. Girish, R. H. Fattepur

Abstract:

In this article, we have given an overview of medical expert systems, which can be used for the developed of physicians in making decisions such as appropriate, prognostic, and therapeutic decisions which help to organize, store, and gives appropriate medical knowledge needed by physicians and practitioners during medical operations or further treatment. If they support the studies by using these systems, advanced tools in medicine will be developed in the future. New trends in the methodology of development of medical expert systems have also been discussed in this paper. So Authors would like to develop an innovative IT based solution to help doctors in rural areas to gain expertise in Medical Science for treating patients. This paper aims to survey the Soft Computing techniques in treating patient’s problems used throughout the world.

Keywords: expert system, fuzzy logic, knowledge base, soft computing, epilepsy

Procedia PDF Downloads 254
1598 Study on Media Literacy and Its Role in Iranian Society (Case Study: Students of Mahmoudabad City)

Authors: Enayat Davoudi

Abstract:

This paper is about the study of media literacy and its role in Iranian society. Determine the research hypothesis by the use of James Patter theory and us stratification and also culture theory. By the use of traversal method and by the aim of the survey on 375 students in Mahmoudabad which was selected randomly, the data was gathered and analyzed by SPSS software. Coefficient alpha for Crohn Bach is used in order to reach to the justifiability of indexes. The research findings show that the variable like duration, rate and type of media use, the realization of media content, audience goal and motivation, economical and social base and the rate of education has a meaningful relation with media literacy.

Keywords: media, media literacy, Iranian society, Mahmoudabad students

Procedia PDF Downloads 297
1597 An intelligent Troubleshooting System and Performance Evaluator for Computer Network

Authors: Iliya Musa Adamu

Abstract:

This paper seeks to develop an expert system that would troubleshoot computer network and evaluate the network system performance so as to reduce the workload on technicians and increase the efficiency and effectiveness of solutions proffered to computer network problems. The platform of the system was developed using ASP.NET, whereas the codes are implemented in Visual Basic and integrated with SQL Server 2005. The knowledge base was represented using production rule, whereas the searching method that was used in developing the network troubleshooting expert system is the forward-chaining-rule-based-system. This software tool offers the advantage of providing an immediate solution to most computer network problems encountered by computer users.

Keywords: expert system, forward chaining rule based system, network, troubleshooting

Procedia PDF Downloads 647
1596 The Relationship between the Social Entrepreneur and the Social Dimension of Sustainability: A Bibliometric Survey of the Last Twelve Years

Authors: Leticia Lengler, Jefferson Oliveira, Vania Estivalete, Jordana Marques Kneipp, Lucia Regina Da Rosa Gama Madruga

Abstract:

The way social entrepreneurs act and can positively impact on our society engages the interest of academics, companies and governments, who seek solutions to solve or alleviate issues related to the abuse of natural resources, as well as the increase of poverty (social aspects). Studies on social entrepreneurship have been characterized by diverse ramifications and their transdisciplinary character, permeating various disciplines and approaches. Different bibliometric studies were conducted within the theme of social entrepreneurship. In this context, because it is a topic in development and multifaceted, the aim of this article is to present the main interfaces of the studies on the Social Entrepreneur figure in relation to the social concern of sustainability, highlighting the relevant researches and their trends, as well as their relationship with the organizations. Aiming to achieve this purpose, the specific goals are: to identify the most cited authors and articles, to verify the authors and journals with the greatest number of publications and their approaches and to point out their affiliations, countries, and languages of publications. It is still a secondary objective to identify the emerging trends in relation to the social entrepreneur and his social concern stemming from the discussions on sustainability. This way, we analyzed articles from two international databases (Scopus and Web of Science), from 2004 to 2016. The main results were the increase in the number of publications, with most of them in English language, coming mainly from the United States institutions (such as Indiana University and Harvard University) and the United Kingdom (whose main institutions are University of London and Robert Gordon University). Although publications in Spanish and Portuguese are the least expressive in quantity, some tendencies point to publications that discuss the social entrepreneur in terms of gender (that relates to female entrepreneurship) and social class (that relates to the need of building communities that contemplate the Social entrepreneur at the base of the pyramid). It should be noted that the trends of the themes emerged from the analysis of the publication titles only in Portuguese, since this is the native language of the authors who carry out their studies mainly in Brazil. When considering articles in Portuguese (57 indicated by WOS and 9 by Scopus), a previous analysis of the titles was carried out to identify how researchers were approaching the theme social entrepreneur in a joint way to the social dimension of sustainability. However, the analysis of the titles themselves brought a limitation to our study, since it was felt a need to carry out a qualitative study, in which it could be possible to consider the abstracts of the available articles.

Keywords: base of pyramid, social dimension, social entrepreneur, sustainability

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1595 The Theory of Relativity (K)

Authors: Igor Vladimirovich Kuzminov

Abstract:

The proposed article is an alternative version of the Theory of Relativity. The version is based on the concepts of classical Newtonian physics and does not deny the existing calculation base. The proposed theory completely denies Einstein's existing Theory of Relativity. The only thing that connects these theories is that the proposed theory is also built on postulates. The proposed theory is intended to establish the foundation of classical Newtonian physics. The proposed theory is intended to establish continuity in the development of the fundamentals of physics and is intended to eliminate all kinds of speculation in explanations of physical phenomena. An example of such speculation is Einstein's Theory of Relativity (E).

Keywords: the theory of relativity, postulates of the theory of relativity, criticism of Einstein's theory, classical physics

Procedia PDF Downloads 50
1594 A Proof of the Fact that a Finite Morphism is Proper

Authors: Ying Yi Wu

Abstract:

In this paper, we present a proof of the fact that a finite morphism is proper. We show that a finite morphism is universally closed and of finite type, which are the conditions for properness. Our proof is based on the theory of schemes and involves the use of the projection formula and the base change theorem. We first show that a finite morphism is of finite type and then proceed to show that it is universally closed. We use the fact that a finite morphism is also an affine morphism, which allows us to use the theory of coherent sheaves and their modules. We then show that the map induced by a finite morphism is flat and that the module it induces is of finite type. We use these facts to show that a finite morphism is universally closed. Our proof is constructive, and we provide details for each step of the argument.

Keywords: finite, morphism, schemes, projection.

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1593 Entrepreneurship the Bed Rock and Mainstram of World Economy

Authors: Njeze Anthony

Abstract:

In the world economy, entrepreneurship is an outstanding venture. Failures in the businesses of over 70% of Entrepreneurs can be attributed to lack of proper planning. For an entrepreneur to succeed, there are some vital planning strategies that will come into play such as organizational, operational, financial and marketing plans. When an entrepreneur lacks the above mentioned, such an entrepreneur is bound to encounter a catastrophic failure. An entrepreneur with an adequate plan will examine his/her own goals, know why he is in business, look at the venture resource base, have a sound knowledge of his proposed venture and identify obstacles that will be surmounted to achieve the desired goals. This work is aimed at identifying the organizational, operational, financial and marketing impact of entrepreneurship in the world economy and as well the important issues in global entrepreneurship, possible obstacles, and solutions.

Keywords: economy, entrepreneurship, business, operation

Procedia PDF Downloads 456
1592 Realization of a Temperature Based Automatic Controlled Domestic Electric Boiling System

Authors: Shengqi Yu, Jinwei Zhao

Abstract:

This paper presents a kind of analog circuit based temperature control system, which is mainly composed by threshold control signal circuit, synchronization signal circuit and trigger pulse circuit. Firstly, the temperature feedback signal function is realized by temperature sensor TS503F3950E. Secondly, the main control circuit forms the cycle controlled pulse signal to control the thyristor switching model. Finally two reverse paralleled thyristors regulate the output power by their switching state. In the consequence, this is a modernized and energy-saving domestic electric heating system.

Keywords: time base circuit, automatic control, zero-crossing trigger, temperature control

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1591 Airborne Molecular Contamination in Clean Room Environment

Authors: T. Rajamäki

Abstract:

In clean room environment molecular contamination in very small concentrations can cause significant harm for the components and processes. This is commonly referred as airborne molecular contamination (AMC). There is a shortage of high sensitivity continuous measurement data for existence and behavior of several of these contaminants. Accordingly, in most cases correlation between concentration of harmful molecules and their effect on processes is not known. In addition, the formation and distribution of contaminating molecules are unclear. In this work sensitive optical techniques are applied in clean room facilities for investigation of concentrations, forming mechanisms and effects of contaminating molecules. Special emphasis is on reactive acid and base gases ammonia (NH3) and hydrogen fluoride (HF). They are the key chemicals in several operations taking place in clean room processes.

Keywords: AMC, clean room, concentration, reactive gas

Procedia PDF Downloads 281
1590 Ruminal VFA of Beef Fed Different Protein

Authors: P. Paengkoum, S. C. Chen, S. Paengkoum

Abstract:

Six male growing Thai-indigenous beef cattle with body weight (BW) of 154±13.2 kg were randomly assigned in replicated 3×3 Latin square design, and fed with different levels of crude protein (CP) in total mixed ration (TMR) diets. CP levels in diets were 4.3%, 7.3% and 10.3% base on dry matter (DM). Ruminal ammonia nitrogen (NH3-N) and blood urea nitrogen (BUN) concentrations increased (P<0.01) with increasing CP levels. Moreover, there is a positive relationship between BUN and ruminal NH3-N. Rumen pH, total volatile fatty acid (VFA), molar proportions of acetate, propionate and butyrate were not affected by CP levels (P>0.05).

Keywords: Thai-indigenous beef cattle, crude protein, volatile fatty acid (VFA), total mixed ration (TMR) diets

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1589 Numerical Simulation of Seismic Process Accompanying the Formation of Shear-Type Fault Zone in Chuya-Kuray Depressions

Authors: Mikhail O. Eremin

Abstract:

Seismic activity around the world is clearly a threat to people's lives, as well as infrastructure and capital construction. It is the instability of the latter to powerful earthquakes that most often causes human casualties. Therefore, during construction it is necessary to take into account the risks of large-scale natural disasters. The task of assessing the risks of natural disasters is one of the most urgent at the present time. The final goal of any study of earthquakes is forecasting. This is especially important for seismically active regions of the planet where earthquakes occur frequently. Gorni Altai is one of such regions. In work, we developed the physical-mathematical model of stress-strain state evolution of loaded geomedium with the purpose of numerical simulation of seismic process accompanying the formation of Chuya-Kuray fault zone Gorni Altay, Russia. We build a structural model on the base of seismotectonic and paleoseismogeological investigations, as well as SRTM-data. Base of mathematical model is the system of equations of solid mechanics which includes the fundamental conservation laws and constitutive equations for elastic (Hooke's law) and inelastic deformation (modified model of Drucker-Prager-Nikolaevskii). An initial stress state of the model correspond to gravitational. Then we simulate an activation of a buried dextral strike-slip paleo-fault located in the basement of the model. We obtain the stages of formation and the structure of Chuya-Kuray fault zone. It is shown that results of numerical simulation are in good agreement with field observations in statistical sense. Simulated seismic process is strongly bound to the faults - lineaments with high degree of inelastic strain localization. Fault zone represents en-echelon system of dextral strike-slips according to the Riedel model. The system of surface lineaments is represented with R-, R'-shear bands, X- and Y-shears, T-fractures. Simulated seismic process obeys the laws of Gutenberg-Richter and Omori. Thus, the model describes a self-similar character of deformation and fracture of rocks and geomedia. We also modified the algorithm of determination of separate slip events in the model due to the features of strain rates dependence vs time.

Keywords: Drucker-Prager model, fault zone, numerical simulation, Riedel bands, seismic process, strike-slip fault

Procedia PDF Downloads 140