Search results for: HyperText Transfer Protocol
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 3784

Search results for: HyperText Transfer Protocol

3724 Survey on Securing the Optimized Link State Routing (OLSR) Protocol in Mobile Ad-hoc Network

Authors: Kimaya Subhash Gaikwad, S. B. Waykar

Abstract:

The mobile ad-hoc network (MANET) is collection of various types of nodes. In MANET various protocols are used for communication. In OLSR protocol, a node is selected as multipoint relay (MPR) node which broadcast the messages. As the MANET is open kind of network any malicious node can easily enter into the network and affect the performance of the network. The performance of network mainly depends on the components which are taking part into the communication. If the proper nodes are not selected for the communication then the probability of network being attacked is more. Therefore, it is important to select the more reliable and secure components in the network. MANET does not have any filtering so that only selected nodes can be used for communication. The openness of the MANET makes it easier to attack the communication. The most of the attack are on the Quality of service (QoS) of the network. This paper gives the overview of the various attacks that are possible on OLSR protocol and some solutions. The papers focus mainly on the OLSR protocol.

Keywords: communication, MANET, OLSR, QoS

Procedia PDF Downloads 421
3723 Wireless Sensor Networks Optimization by Using 2-Stage Algorithm Based on Imperialist Competitive Algorithm

Authors: Hamid R. Lashgarian Azad, Seyed N. Shetab Boushehri

Abstract:

Wireless sensor networks (WSN) have become progressively popular due to their wide range of applications. Wireless Sensor Network is made of numerous tiny sensor nodes that are battery-powered. It is a very significant problem to maximize the lifetime of wireless sensor networks. In this paper, we propose a two-stage protocol based on an imperialist competitive algorithm (2S-ICA) to solve a sensor network optimization problem. The energy of the sensors can be greatly reduced and the lifetime of the network reduced by long communication distances between the sensors and the sink. We can minimize the overall communication distance considerably, thereby extending the lifetime of the network lifetime through connecting sensors into a series of independent clusters using 2SICA. Comparison results of the proposed protocol and LEACH protocol, which is common to solving WSN problems, show that our protocol has a better performance in terms of improving network life and increasing the number of transmitted data.

Keywords: wireless sensor network, imperialist competitive algorithm, LEACH protocol, k-means clustering

Procedia PDF Downloads 57
3722 Key Issues in Transfer Stage of BOT Project: Experience from China

Authors: Wang Liguang, Zhang Xueqing

Abstract:

The build-operate-transfer (BOT) project delivery system has provided effective routes to mobilize private sector funds, innovative technologies, management skills and operational efficiencies for public infrastructure development and have been widely used in China during the last 20 years. Many BOT projects in China will be smoothly transferred to the government soon and the transfer stage, which is considered as the last stage, must be studied carefully and handled well to achieve the overall success of BOT projects. There will be many issues faced by both the public sector and private sector in the transfer stage of BOT projects, including project post-assessment, technology and documents transfer, personal training and staff transition, etc. and sometimes additional legislation is needed for future operation and management of facilities. However, most previous studies focused on the bidding, financing, and building and operation stages instead of transfer stage. This research identifies nine key issues in the transfer stage of BOT projects through a comprehensive study on three cases in China, and the expert interview and expert discussion meetings are held to validate the key issues and give detail analysis. A proposed framework of transfer management is prepared based on the experiences derived and lessons drawn from the case studies and expert interview and discussions, which is expected to improve the transfer management of BOT projects in practice.

Keywords: BOT project, key issues, transfer management, transfer stage

Procedia PDF Downloads 218
3721 Analytical Validity Of A Tech Transfer Solution To Internalize Genetic Testing

Authors: Lesley Northrop, Justin DeGrazia, Jessica Greenwood

Abstract:

ASPIRA Labs now offers an en-suit and ready-to-implement technology transfer solution to enable labs and hospitals that lack the resources to build it themselves to offer in-house genetic testing. This unique platform employs a patented Molecular Inversion Probe (MIP) technology that combines the specificity of a hybrid capture protocol with the ease of an amplicon-based protocol and utilizes an advanced bioinformatics analysis pipeline based on machine learning. To demonstrate its efficacy, two independent genetic tests were validated on this technology transfer platform: expanded carrier screening (ECS) and hereditary cancer testing (HC). The analytical performance of ECS and HC was validated separately in a blinded manner for calling three different types of variants: SNVs, short indels (typically, <50 bp), and large indels/CNVs defined as multi-exonic del/dup events. The reference set was constructed using samples from Coriell Institute, an external clinical genetic testing laboratory, Maine Molecular Quality Controls Inc. (MMQCI), SeraCare and GIAB Consortium. Overall, the analytical performance showed a sensitivity and specificity of >99.4% for both ECS and HC in detecting SNVs. For indels, both tests reported specificity of 100%, and ECS demonstrated a sensitivity of 100%, whereas HC exhibited a sensitivity of 96.5%. The bioinformatics pipeline also correctly called all reference CNV events resulting in a sensitivity of 100% for both tests. No additional calls were made in the HC panel, leading to a perfect performance (specificity and F-measure of 100%). In the carrier panel, however, three additional positive calls were made outside the reference set. Two of these calls were confirmed using an orthogonal method and were re-classified as true positives leaving only one false positive. The pipeline also correctly identified all challenging carrier statuses, such as positive cases for spinal muscular atrophy and alpha-thalassemia, resulting in 100% sensitivity. After confirmation of additional positive calls via long-range PCR and MLPA, specificity for such cases was estimated at 99%. These performance metrics demonstrate that this tech-transfer solution can be confidently internalized by clinical labs and hospitals to offer mainstream ECS and HC as part of their test catalog, substantially increasing access to quality germline genetic testing for labs of all sizes and resources levels.

Keywords: clinical genetics, genetic testing, molecular genetics, technology transfer

Procedia PDF Downloads 153
3720 Performance Analysis of Deterministic Stable Election Protocol Using Fuzzy Logic in Wireless Sensor Network

Authors: Sumanpreet Kaur, Harjit Pal Singh, Vikas Khullar

Abstract:

In Wireless Sensor Network (WSN), the sensor containing motes (nodes) incorporate batteries that can lament at some extent. To upgrade the energy utilization, clustering is one of the prototypical approaches for split sensor motes into a number of clusters where one mote (also called as node) proceeds as a Cluster Head (CH). CH selection is one of the optimization techniques for enlarging stability and network lifespan. Deterministic Stable Election Protocol (DSEP) is an effectual clustering protocol that makes use of three kinds of nodes with dissimilar residual energy for CH election. Fuzzy Logic technology is used to expand energy level of DSEP protocol by using fuzzy inference system. This paper presents protocol DSEP using Fuzzy Logic (DSEP-FL) CH by taking into account four linguistic variables such as energy, concentration, centrality and distance to base station. Simulation results show that our proposed method gives more effective results in term of a lifespan of network and stability as compared to the performance of other clustering protocols.

Keywords: DSEP, fuzzy logic, energy model, WSN

Procedia PDF Downloads 172
3719 Developing a Cloud Intelligence-Based Energy Management Architecture Facilitated with Embedded Edge Analytics for Energy Conservation in Demand-Side Management

Authors: Yu-Hsiu Lin, Wen-Chun Lin, Yen-Chang Cheng, Chia-Ju Yeh, Yu-Chuan Chen, Tai-You Li

Abstract:

Demand-Side Management (DSM) has the potential to reduce electricity costs and carbon emission, which are associated with electricity used in the modern society. A home Energy Management System (EMS) commonly used by residential consumers in a down-stream sector of a smart grid to monitor, control, and optimize energy efficiency to domestic appliances is a system of computer-aided functionalities as an energy audit for residential DSM. Implementing fault detection and classification to domestic appliances monitored, controlled, and optimized is one of the most important steps to realize preventive maintenance, such as residential air conditioning and heating preventative maintenance in residential/industrial DSM. In this study, a cloud intelligence-based green EMS that comes up with an Internet of Things (IoT) technology stack for residential DSM is developed. In the EMS, Arduino MEGA Ethernet communication-based smart sockets that module a Real Time Clock chip to keep track of current time as timestamps via Network Time Protocol are designed and implemented for readings of load phenomena reflecting on voltage and current signals sensed. Also, a Network-Attached Storage providing data access to a heterogeneous group of IoT clients via Hypertext Transfer Protocol (HTTP) methods is configured to data stores of parsed sensor readings. Lastly, a desktop computer with a WAMP software bundle (the Microsoft® Windows operating system, Apache HTTP Server, MySQL relational database management system, and PHP programming language) serves as a data science analytics engine for dynamic Web APP/REpresentational State Transfer-ful web service of the residential DSM having globally-Advanced Internet of Artificial Intelligence (AI)/Computational Intelligence. Where, an abstract computing machine, Java Virtual Machine, enables the desktop computer to run Java programs, and a mash-up of Java, R language, and Python is well-suited and -configured for AI in this study. Having the ability of sending real-time push notifications to IoT clients, the desktop computer implements Google-maintained Firebase Cloud Messaging to engage IoT clients across Android/iOS devices and provide mobile notification service to residential/industrial DSM. In this study, in order to realize edge intelligence that edge devices avoiding network latency and much-needed connectivity of Internet connections for Internet of Services can support secure access to data stores and provide immediate analytical and real-time actionable insights at the edge of the network, we upgrade the designed and implemented smart sockets to be embedded AI Arduino ones (called embedded AIduino). With the realization of edge analytics by the proposed embedded AIduino for data analytics, an Arduino Ethernet shield WizNet W5100 having a micro SD card connector is conducted and used. The SD library is included for reading parsed data from and writing parsed data to an SD card. And, an Artificial Neural Network library, ArduinoANN, for Arduino MEGA is imported and used for locally-embedded AI implementation. The embedded AIduino in this study can be developed for further applications in manufacturing industry energy management and sustainable energy management, wherein in sustainable energy management rotating machinery diagnostics works to identify energy loss from gross misalignment and unbalance of rotating machines in power plants as an example.

Keywords: demand-side management, edge intelligence, energy management system, fault detection and classification

Procedia PDF Downloads 225
3718 Development of Medical Intelligent Process Model Using Ontology Based Technique

Authors: Emmanuel Chibuogu Asogwa, Tochukwu Sunday Belonwu

Abstract:

An urgent demand for creative solutions has been created by the rapid expansion of medical knowledge, the complexity of patient care, and the requirement for more precise decision-making. As a solution to this problem, the creation of a Medical Intelligent Process Model (MIPM) utilizing ontology-based appears as a promising way to overcome this obstacle and unleash the full potential of healthcare systems. The development of a Medical Intelligent Process Model (MIPM) using ontology-based techniques is motivated by a lack of quick access to relevant medical information and advanced tools for treatment planning and clinical decision-making, which ontology-based techniques can provide. The aim of this work is to develop a structured and knowledge-driven framework that leverages ontology, a formal representation of domain knowledge, to enhance various aspects of healthcare. Object-Oriented Analysis and Design Methodology (OOADM) were adopted in the design of the system as we desired to build a usable and evolvable application. For effective implementation of this work, we used the following materials/methods/tools: the medical dataset for the test of our model in this work was obtained from Kaggle. The ontology-based technique was used with Confusion Matrix, MySQL, Python, Hypertext Markup Language (HTML), Hypertext Preprocessor (PHP), Cascaded Style Sheet (CSS), JavaScript, Dreamweaver, and Fireworks. According to test results on the new system using Confusion Matrix, both the accuracy and overall effectiveness of the medical intelligent process significantly improved by 20% compared to the previous system. Therefore, using the model is recommended for healthcare professionals.

Keywords: ontology-based, model, database, OOADM, healthcare

Procedia PDF Downloads 44
3717 Development of a Nurse Led Tranexamic Acid Administration Protocol for Trauma Patients in Rural South Africa

Authors: Christopher Wearmouth, Jacob Smith

Abstract:

Administration of tranexamic acid (TXA) reduces all-cause mortality in trauma patients when given within 3 hours of injury. Due to geographical distance and lack of emergency medical services patients often present late, following trauma, to our emergency department. Additionally, we found patients that may have benefited from TXA did not receive it, often due to lack of staff awareness, staff shortages out of hours and lack of equipment for delivering infusions. Our objective was to develop a protocol for nurse-led administration of TXA in the emergency department. We developed a protocol using physiological observations along with criteria from the South African Triage Scale to allow nursing staff to identify patients with, or at risk of, significant haemorrhage. We will monitor the use of the protocol to ensure appropriate compliance and for any adverse events reported.

Keywords: emergency department, emergency nursing, rural healthcare, tranexamic acid, trauma, triage

Procedia PDF Downloads 203
3716 [Keynote Talk]: Formal Specification and Description Language and Message Sequence Chart to Model and Validate Session Initiation Protocol Services

Authors: Sa’ed Abed, Mohammad H. Al Shayeji, Ovais Ahmed, Sahel Alouneh

Abstract:

Session Initiation Protocol (SIP) is a signaling layer protocol for building, adjusting and ending sessions among participants including Internet conferences, telephone calls and multimedia distribution. SIP facilitates user movement by proxying and forwarding requests to the present location of the user. In this paper, we provide a formal Specification and Description Language (SDL) and Message Sequence Chart (MSC) to model and define the Internet Engineering Task Force (IETF) SIP protocol and its sample services resulted from informal SIP specification. We create an “Abstract User Interface” using case analysis so that can be applied to identify SIP services more explicitly. The issued sample SIP features are then used as case scenarios; they are revised in MSCs format and validated to their corresponding SDL models.

Keywords: modeling, MSC, SDL, SIP, validating

Procedia PDF Downloads 183
3715 Reactive Analysis of Different Protocol in Mobile Ad Hoc Network

Authors: Manoj Kumar

Abstract:

Routing protocols have a central role in any mobile ad hoc network (MANET). There are many routing protocols that exhibit different performance levels in different scenarios. In this paper, we compare AODV, DSDV, DSR, and ZRP routing protocol in mobile ad hoc networks to determine the best operational conditions for each protocol. We analyze these routing protocols by extensive simulations in OPNET simulator and show how to pause time and the number of nodes affect their performance. In this study, performance is measured in terms of control traffic received, control traffic sent, data traffic received, sent data traffic, throughput, retransmission attempts.

Keywords: AODV, DSDV, DSR, ZRP

Procedia PDF Downloads 487
3714 Heat Transfer Studies on CNT Nanofluids in a Turbulent Flow Heat Exchanger

Authors: W. Rashmi, M. Khalid, O. Seiksan, R. Saidur, A. F. Ismail

Abstract:

Nanofluids have received much more attention since its discovery. They are believed to be promising coolants in heat transfer applications due to their enhanced thermal conductivity and heat transfer characteristics. In this study, the enhancement in heat transfer of CNT-nanofluids under turbulent flow conditions is investigated experimentally. Carbon nanotube (CNTs) concentration was varied between 0.051-0.085 wt%. The nanofluid suspension was stabilized by gum arabic (GA) through a process of homogenisation and sonication. The flow rates of cold fluid (water) is varied from 1.7-3 L/min and flow rates of the hot fluid is varied between 2-3.5 L/min. Thermal conductivity, density and viscosity of the nanofluids were also measured as a function of temperature and CNT concentration. The experimental results are validated with theoretical correlations for turbulent flow available in the literature. Results showed an enhancement in heat transfer range between 9-67% as a function of temperature and CNT concentration.

Keywords: nanofluids, carbon nanotubes (CNT), heat transfer enhancement, heat transfer

Procedia PDF Downloads 471
3713 Orphan Node Inclusion Protocol for Wireless Sensor Network

Authors: Sandeep Singh Waraich

Abstract:

Wireless sensor network (WSN ) consists of a large number of sensor nodes. The disparity in their energy consumption usually lead to the loss of equilibrium in wireless sensor network which may further results in an energy hole problem in wireless network. In this paper, we have considered the inclusion of orphan nodes which usually remain unutilized as intermediate nodes in multi-hop routing. The Orphan Node Inclusion (ONI) Protocol lets the cluster member to bring the orphan nodes into their clusters, thereby saving important resources and increasing network lifetime in critical applications of WSN.

Keywords: wireless sensor network, orphan node, clustering, ONI protocol

Procedia PDF Downloads 388
3712 A Low Power Consumption Routing Protocol Based on a Meta-Heuristics

Authors: Kaddi Mohammed, Benahmed Khelifa D. Benatiallah

Abstract:

A sensor network consists of a large number of sensors deployed in areas to monitor and communicate with each other through a wireless medium. The collected routing data in the network consumes most of the energy of the sensor nodes. For this purpose, multiple routing approaches have been proposed to conserve energy resource at the sensors and to overcome the challenges of its limitation. In this work, we propose a new low energy consumption routing protocol for wireless sensor networks based on a meta-heuristic methods. Our protocol is to operate more fairly energy when routing captured data to the base station.

Keywords: WSN, routing, energy, heuristic

Procedia PDF Downloads 314
3711 CFD Simulation of Forced Convection Nanofluid Heat Transfer in the Automotive Radiator

Authors: Sina Movafagh, Younes Bakhshan

Abstract:

Heat transfer of coolant flow through the automobile radiators is of great importance for the optimization of fuel consumption. In this study, the heat transfer performance of the automobile radiator is evaluated numerically. Different concentrations of nanofluids have been investigated by the addition of Al2O3 nano-particles into the water. Also, the effect of the inlet temperature of nanofluid on the performance of radiator is studied. Results show that with an increase of inlet temperature the outlet temperature and pressure drop along the radiator increase. Also, it has been observed that increase of nono-particle concentration will result in an increase in heat transfer rate within the radiator.

Keywords: heat transfer, nanofluid, car radiator, CFD simulation

Procedia PDF Downloads 276
3710 A Transfer Function Representation of Thermo-Acoustic Dynamics for Combustors

Authors: Myunggon Yoon, Jung-Ho Moon

Abstract:

In this paper, we present a transfer function representation of a general one-dimensional combustor. The input of the transfer function is a heat rate perturbation of a burner and the output is a flow velocity perturbation at the burner. This paper considers a general combustor model composed of multiple cans with different cross sectional areas, along with a non-zero flow rate.

Keywords: combustor, dynamics, thermoacoustics, transfer function

Procedia PDF Downloads 354
3709 A Novel Comparison Scheme for Thermal Conductivity Enhancement of Heat Transfer

Authors: Islam Tarek, Moataz Soliman

Abstract:

With the amazing development of nanoscience’s and the discovery of the unique properties of nanometric materials, the ideas of scientists and researchers headed to take advantage of this progress in various fields, and one of the most important of these areas is the field of heat transfer and benefit from it in saving energy used for heat transfer, so nanometric materials were used to improve the properties of heat transfer fluids and increase the efficiency of the liquid. In this paper, we will compare two types of heat transfer fluid, one industrial type (the base fluid is a mix of ethylene glycol and deionized water ) and another natural oils(the base fluid is a mix of jatropha oil and expired olive oil), explaining the method of preparing each of them, starting from the method of preparing CNT, collecting and sorting jatropha seeds, and the most appropriate method for extracting oil from them, and characterization the both of two fluids and when to use both.

Keywords: nanoscience, heat transfer, thermal conductivity, jatropha oil

Procedia PDF Downloads 186
3708 On Virtual Coordination Protocol towards 5G Interference Mitigation: Modelling and Performance Analysis

Authors: Bohli Afef

Abstract:

The fifth-generation (5G) wireless systems is featured by extreme densities of cell stations to overcome the higher future demand. Hence, interference management is a crucial challenge in 5G ultra-dense cellular networks. In contrast to the classical inter-cell interference coordination approach, which is no longer fit for the high density of cell-tiers, this paper proposes a novel virtual coordination based on the dynamic common cognitive monitor channel protocol to deal with the inter-cell interference issue. A tractable and flexible model for the coverage probability of a typical user is developed through the use of the stochastic geometry model. The analyses of the performance of the suggested protocol are illustrated both analytically and numerically in terms of coverage probability.

Keywords: ultra dense heterogeneous networks, dynamic common channel protocol, cognitive radio, stochastic geometry, coverage probability

Procedia PDF Downloads 297
3707 Mask-Prompt-Rerank: An Unsupervised Method for Text Sentiment Transfer

Authors: Yufen Qin

Abstract:

Text sentiment transfer is an important branch of text style transfer. The goal is to generate text with another sentiment attribute based on a text with a specific sentiment attribute while maintaining the content and semantic information unrelated to sentiment unchanged in the process. There are currently two main challenges in this field: no parallel corpus and text attribute entanglement. In response to the above problems, this paper proposed a novel solution: Mask-Prompt-Rerank. Use the method of masking the sentiment words and then using prompt regeneration to transfer the sentence sentiment. Experiments on two sentiment benchmark datasets and one formality transfer benchmark dataset show that this approach makes the performance of small pre-trained language models comparable to that of the most advanced large models, while consuming two orders of magnitude less computing and memory.

Keywords: language model, natural language processing, prompt, text sentiment transfer

Procedia PDF Downloads 48
3706 A Novel Unconditionally Secure and Lightweight Bipartite Key Agreement Protocol

Authors: Jun Liu

Abstract:

This paper introduces a new bipartite key agreement (2PKA) protocol which provides unconditionally security and lightweight. The unconditional security is stemmed from the known impossibility of distinguishing a particular solution from all possible solutions of an underdetermined system of equations. The indistinguishability prevents an adversary from inferring to the common secret-key even with the access to an unlimited amount of computing capability. This new 2PKA protocol is also lightweight because that the calculation of a common secret-key only makes use of simple modular arithmetic. This information-theoretic 2PKA scheme provides the desired features of Key Confirmation (KC), Session Key (SK) security, Know-Key (KK) security, protection of individual privacy, and uniformly distributed value of a common key under prime modulus.

Keywords: bipartite key agreement, information-theoretic cryptography, perfect security, lightweight

Procedia PDF Downloads 28
3705 Investigation of Heat Transfer of Nanofluids in Circular Microchannels

Authors: Bayram Sahin, Hourieh Bayramian, Emre Mandev, Murat Ceylan

Abstract:

In industrial applications, the demand for the enhancement of heat transfer is a common engineering problem. The use of additives to heat transfer fluid is a technique applied to enhance the heat transfer performance of base fluids. In this study, the thermal performance of nanofluids consisting of SiO2 particles and deionized water in circular microchannels was investigated experimentally. SiO2 nanoparticles with diameter of 15 nm were added to water to prepare nanofluids with 0.2% and 0.4% volume fractions. Heat transfer characteristics were calculated by using temperature, flow and pressure measurements. The thermal conductivity and viscosity values required for the calculations are measured separately. It is observed that the Nusselt number increases at the all volume fraction of particles, by increasing the Reynolds number and the volumetric ratios of the particles. The highest heat transfer enhancement is obtained at Re = 2160 and 0.4 % vol. by 14% under the condition of a constant pumping power.

Keywords: nanofluid, microchannel, heat transfer, SiO2-water nanofluid

Procedia PDF Downloads 357
3704 Mixed Convection Heat Transfer of Copper Oxide-Heat Transfer Oil Nanofluid in Vertical Tube

Authors: Farhad Hekmatipour, M. A. Akhavan-Behabadi, Farzad Hekmatipour

Abstract:

In this paper, experiments were conducted to investigate the heat transfer of Copper Oxide-Heat Transfer Oil (CuO-HTO) nanofluid laminar flow in vertical smooth and microfin tubes as the surface temperature is constant. The effect of adding the nanoparticle to base fluid and Richardson number on the heat transfer enhancement is investigated as Richardson number increases from 0.1 to 0.7. The experimental results demonstrate that the combined forced-natural convection heat transfer rate may be improved significantly with an increment of mass nanoparticle concentration from 0% to 1.5%. In this experiment, a correlation is also proposed to predict the mixed convection heat transfer rate of CuO-HTO nanofluid flow. The maximum deviation of both correlations is less than 14%. Moreover, a correlation is presented to estimate the Nusselt number inside vertical smooth and microfin tubes as Rayleigh number is between 2´105 and 6.8´106 with the maximum deviation of 12%.

Keywords: mixed convection, heat transfer, nanofluid, vertical tube, microfin tube

Procedia PDF Downloads 353
3703 Heat Transfer from a Cylinder in Cross-Flow of Single and Multiphase Flows

Authors: F. A. Hamad, S. He

Abstract:

In this paper, the average heat transfer characteristics for a cross flow cylinder of 16 mm diameter in a vertical pipe has been studied for single-phase flow (water/oil) and multicomponent (non-boiling) flow (water-air, water-oil, oil-air and water-oil-air). The cylinder is uniformly heated by electrical heater placed at the centre of the element. The results show that the values of average heat transfer coefficients for water are around four times the values for oil flow. Introducing air as a second phase with water has very little effect on heat transfer rate, while the heat transfer increased by 70% in case of oil. For water–oil flow, the heat transfer coefficient values are reflecting the percentage of water up to 50%, but increasing the water more than 50% leads to a sharp increase in the heat transfer coefficients to become close to the values of pure water. The enhancement of heat transfer by mixing two phases may be attributed to the changes in flow structure near to cylinder surface which lead to thinner boundary layer and higher turbulence. For three-phase flow, the heat transfer coefficients for all cases fall within the limit of single-phase flow of water and oil and are very close to pure water values. The net effect of the turbulence augmentation due to the introduction of air and the attenuation due to the introduction of oil leads to a thinner boundary layer of oil over the cylinder surface covered by a mixture of water and air bubbles.

Keywords: circular cylinder, cross flow, hear transfer, multicomponent multiphase flow

Procedia PDF Downloads 362
3702 An Improved Heat Transfer Prediction Model for Film Condensation inside a Tube with Interphacial Shear Effect

Authors: V. G. Rifert, V. V. Gorin, V. V. Sereda, V. V. Treputnev

Abstract:

The analysis of heat transfer design methods in condensing inside plain tubes under existing influence of shear stress is presented in this paper. The existing discrepancy in more than 30-50% between rating heat transfer coefficients and experimental data has been noted. The analysis of existing theoretical and semi-empirical methods of heat transfer prediction is given. The influence of a precise definition concerning boundaries of phase flow (it is especially important in condensing inside horizontal tubes), shear stress (friction coefficient) and heat flux on design of heat transfer is shown. The substantiation of boundary conditions of the values of parameters, influencing accuracy of rated relationships, is given. More correct relationships for heat transfer prediction, which showed good convergence with experiments made by different authors, are substantiated in this work.

Keywords: film condensation, heat transfer, plain tube, shear stress

Procedia PDF Downloads 219
3701 Patent License of Transfer Technology: Challenges and Opportunities in Indonesia

Authors: Agung Sujatmiko

Abstract:

One of the purposes of patent licensing was to transfer technology from developed countries to developing countries. For this reason, the role of the patent license agreement was very important and had a function as a tool to achieve technological development. This goal was very good, but in fact, many problems and obstacles arose in its implementation, so the technology transfer that had been implemented had not given good results. For this reason, it was necessary to find a solution so that technology could switch properly. The problem approach used the statutory and conceptual approaches. The analysis used was deductive by analyzing general laws and regulations and then concluding. Several regulations related to technology transfer were the main source to find answers to why technology transfer was difficult to achieve and what caused it. Once the cause was known, a solution would be sought.

Keywords: license, patent, technology, tie in clause

Procedia PDF Downloads 62
3700 The Study of Sintered Wick Structure of Heat Pipes with Excellent Heat Transfer Capabilities

Authors: Im-Nam Jang, Yong-Sik Ahn

Abstract:

In this study sintered wick was formed in a heat pipe through the process of sintering a mixture of copper powder with particle sizes of 100μm and 200μm, mixed with a pore-forming agent. The heat pipe's thermal resistance, which affects its heat transfer efficiency, is determined during manufacturing according to powder type, thickness of the sintered wick, and filling rate of the working fluid. Heat transfer efficiency was then tested at various inclination angles (0°, 45°, 90°) to evaluate the performance of heat pipes. Regardless of the filling amount and test angle, the 200μm copper powder type exhibited superior heat transfer efficiency compared to the 100μm type. After analyzing heat transfer performance at various filling rates between 20% and 50%, it was determined that the heat pipe's optimal heat transfer capability occurred at a working fluid filling rate of 30%. The width of the wick was directly related to the heat transfer performance.

Keywords: heat pipe, heat transfer performance, effective pore size, capillary force, sintered wick

Procedia PDF Downloads 27
3699 Diversity and Intensity of International Technology Transfer and their Impacts on Organizational Performance

Authors: Seongryong Kang, Woonjin Kim, Sungjoo Lee

Abstract:

Under the environment of fierce competition and globalized economy, international technology collaboration has gained increasing attention as a way to improve innovation efficiency. While international technology transfer helps a firm to acquire necessary technology in a short period of time, it also has a risk; embedding external technology from overseas partners may cause a transaction cost due to the regional, cultural and language barriers, which tend to offset the benefits of such transfer. Though a number of previous studies have focused on the effects of technology in-transfer on firm performance, few have conducted in the context of international technology transfer. To fill this gap, this study aims to investigate the impact of international technology in-transfer on firm performance – both innovation and financial performance, with a particular emphasis on the diversity and intensity of such transfer. To do this, we adopted technology balance payment (TBP) data of Korean firms from 2010 to 2011, where an intermediate regression analysis was used to identify the intermediate effects of absorptive capacity. The analysis results indicate that i) the diversity and intensity of international technology transfer influence innovation performance by improving R&D capability positively; and ii) the diversity has a positive impact but the intensity has a negative impact on financial performance through the intermediation of R&D intensity. The research findings are expected to provide meaningful implications for establishing global technology strategy and developing policy programs to facilitate technology transfer.

Keywords: diversity, intensity, international technology acquisition, performance, technology transfer

Procedia PDF Downloads 333
3698 System Detecting Border Gateway Protocol Anomalies Using Local and Remote Data

Authors: Alicja Starczewska, Aleksander Nawrat, Krzysztof Daniec, Jarosław Homa, Kacper Hołda

Abstract:

Border Gateway Protocol is the main routing protocol that enables routing establishment between all autonomous systems, which are the basic administrative units of the internet. Due to the poor protection of BGP, it is important to use additional BGP security systems. Many solutions to this problem have been proposed over the years, but none of them have been implemented on a global scale. This article describes a system capable of building images of real-time BGP network topology in order to detect BGP anomalies. Our proposal performs a detailed analysis of BGP messages that come into local network cards supplemented by information collected by remote collectors in different localizations.

Keywords: BGP, BGP hijacking, cybersecurity, detection

Procedia PDF Downloads 50
3697 Comparison of Particle Size for ɑ(Alpha) Fe2O3 and ɤ(Gamma)Fe2O3 on Heat Transfer Performance in an Copper Oscillating Heat Pipe

Authors: Hamid Reza Goshayeshi

Abstract:

The effect of ɑ(alpha) Fe2O3 and ɤ(gamma)Fe2O3 particles on the heat transfer performance of an oscillating heat pipe was investigated experimentally. Kerosene was used as the base fluid for the OHP. Six size particles with average diameters of 10 nm, 20 nm, and 30 nm ɑFe2O3 and ɤFe2O3 were investigated, respectively. Experimental results show that the ɤFe2O3 particles added in the OHP significantly affect the heat transfer performance. When the OHP was charged with kerosene and 20 nm ɤ Fe2O3 particles, the OHP can achieve the best heat transfer performance among six particles investigated in this research.

Keywords: copper oscillating heat pipe, heat transfer, flow, comparison of ɑ(alpha)Fe2O3 and ɤ(gamma)Fe2O3, increase heat transfer

Procedia PDF Downloads 289
3696 Signal Strength Based Multipath Routing for Mobile Ad Hoc Networks

Authors: Chothmal

Abstract:

In this paper, we present a route discovery process which uses the signal strength on a link as a parameter of its inclusion in the route discovery method. The proposed signal-to-interference and noise ratio (SINR) based multipath reactive routing protocol is named as SINR-MP protocol. The proposed SINR-MP routing protocols has two following two features: a) SINR-MP protocol selects routes based on the SINR of the links during the route discovery process therefore it select the routes which has long lifetime and low frame error rate for data transmission, and b) SINR-MP protocols route discovery process is multipath which discovers more than one SINR based route between a given source destination pair. The multiple routes selected by our SINR-MP protocol are node-disjoint in nature which increases their robustness against link failures, as failure of one route will not affect the other route. The secondary route is very useful in situations where the primary route is broken because we can now use the secondary route without causing a new route discovery process. Due to this, the network overhead caused by a route discovery process is avoided. This increases the network performance greatly. The proposed SINR-MP routing protocol is implemented in the trail version of network simulator called Qualnet.

Keywords: ad hoc networks, quality of service, video streaming, H.264/SVC, multiple routes, video traces

Procedia PDF Downloads 219
3695 Out of Hospital Cardiac Arrest in Kuala Lumpur: A Mixed Method Study on Incidence, Adherence to Protocol, and Issues

Authors: Mohd Said Nurumal, Sarah Sheikh Abdul Karim

Abstract:

Information regarding out of hospital cardiac arrest incidence include outcome in Malaysia is limited and fragmented. This study aims to identify incidence and adherence to protocol of out of hospital cardiac arrest and also to explore the issues faced by the pre-hospital personnel in regards managing cardiac arrest victim in Kuala Lumpur, Malaysia. A mixed method approach combining the qualitative and quantitative study design was used. The 285 pre-hospital care data sheet of out of hospital cardiac arrest during the year of 2011 were examined by using checklists for identify the incidence and adherence to protocol. Nine semi-structured interviews and two focus group discussions were performed. For the incidence based on the overall out of hospital cardiac arrest cases that occurred in 2011 (n=285), the survival rates were 16.8%. For adherence to protocol, only 89 (41.8%) of the cases adhered to the given protocol and 124 did not adhere to such protocol. The qualitative information provided insight about the issues related to out of hospital cardiac arrest in every aspect. All the relevant qualitative data were merged into few categories relating issues that could affect the management of out of hospital cardiac arrest performed by pre-hospital care team. One of the essential elements in the out of hospital cardiac arrest handling by pre-hospital care is to ensure increase of survival rates and excellent outcomes by adhering to given protocols based on international standard benchmarks. Measures are needed to strengthen the quick activation of the pre-hospital care service, prompt bystander cardiopulmonary resuscitation, early defibrillation and timely advanced cardiac life support and also to tackle all the issues highlighted in qualitative results.

Keywords: pre-hospital care, out of hospital cardiac arrest, incidence, protocol, mixed method research

Procedia PDF Downloads 389