Search results for: cache timing attack
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 917

Search results for: cache timing attack

707 An MrPPG Method for Face Anti-Spoofing

Authors: Lan Zhang, Cailing Zhang

Abstract:

In recent years, many face anti-spoofing algorithms have high detection accuracy when detecting 2D face anti-spoofing or 3D mask face anti-spoofing alone in the field of face anti-spoofing, but their detection performance is greatly reduced in multidimensional and cross-datasets tests. The rPPG method used for face anti-spoofing uses the unique vital information of real face to judge real faces and face anti-spoofing, so rPPG method has strong stability compared with other methods, but its detection rate of 2D face anti-spoofing needs to be improved. Therefore, in this paper, we improve an rPPG(Remote Photoplethysmography) method(MrPPG) for face anti-spoofing which through color space fusion, using the correlation of pulse signals between real face regions and background regions, and introducing the cyclic neural network (LSTM) method to improve accuracy in 2D face anti-spoofing. Meanwhile, the MrPPG also has high accuracy and good stability in face anti-spoofing of multi-dimensional and cross-data datasets. The improved method was validated on Replay-Attack, CASIA-FASD, Siw and HKBU_MARs_V2 datasets, the experimental results show that the performance and stability of the improved algorithm proposed in this paper is superior to many advanced algorithms.

Keywords: face anti-spoofing, face presentation attack detection, remote photoplethysmography, MrPPG

Procedia PDF Downloads 143
706 The Health Impact of Intensive Case Management on Women with an Opioid Use Disorder and Their Infants

Authors: Shannon Rappe, Elizabeth Morse, David Phillippi

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Postpartum women with an opioid use disorder (OUD) are at high risk for treatment disengagement, leaving them vulnerable to overdose and death between seven and twelve months postpartum. Intensive case management programs have been proposed as an effective strategy to reduce barriers and increase treatment engagement among postpartum women. The purpose of this project is to determine the effects of early engagement in an intensive case management program on postpartum engagement and infant health outcomes among postpartum women with opioid use. This retrospective review of secondary data was collected on 225 infants, and 221 postpartum women enrolled in an intensive case management program in Tennessee between May 1, 2019, and May 5, 2020. Chi-squares were computed to examine the timing of engagement during pregnancy, maternal treatment outcomes, and infant health outcomes, including neonatal abstinence syndrome (NAS), birth weight, gestational age, and length of stay. The mean prenatal program engagement was 109 days (SD = 67.6); 16.7% (n = 37) enrolled during the first trimester, 37.6% (n = 83) in the second trimester, and 45.7% (n = 101) in the third trimester. Of the 221 women engaged, 45.2% (n = 100) remained engaged in the case of management at the time of data collection, and 40% (n = 89) remained engaged in MAT at the time of data collection. Twenty- five percent (n = 25) of mothers who graduated sustained engagement in MAT. Of 225 infants 28.9% (n = 65) had a positive NAS status, mean birth weight was 6.5 lbs. (SD = 19.3); mean gestational age was 38.3 weeks (SD = 19.3) and mean length of stay was 8.19 days (SD = 9.8). This study's findings identified that engaging mothers during pregnancy in a program designed to meet their unique challenges positively impacts both the mother and infant outcomes, regardless of their timing.

Keywords: intensive case management, neonatal abstinence syndrome, opioid addiction, opioid crisis, opioid use in pregnant women, postpartum addiction

Procedia PDF Downloads 176
705 Jagiellonian-PET: A Novel TOF-PET Detector Based on Plastic Scintillators

Authors: P. Moskal, T. Bednarski, P. Bialas, E. Czerwinski, A. Gajos, A. Gruntowski, D. Kaminska, L. Kaplon, G. Korcyl, P. Kowalski, T. Kozik, W. Krzemien, E. Kubicz, Sz. Niedzwiecki, M. Palka, L. Raczynski, Z. Rudy, P. Salabura, N. G. Sharma, M. Silarski, A. Slomski, J. Smyrski, A. Strzelecki, A. Wieczorek, W. Wislicki, M. Zielinski, N. Zon

Abstract:

A new concept and results of the performance tests of the TOF-PET detection system developed at the Jagiellonian University will be presented. The novelty of the concept lies in employing long strips of polymer scintillators instead of crystals as detectors of annihilation quanta, and in using predominantly the timing of signals instead of their amplitudes for the reconstruction of Lines-of-Response. The diagnostic chamber consists of plastic scintillator strips readout by pairs of photo multipliers arranged axially around a cylindrical surface. To take advantage of the superior timing properties of plastic scintillators the signals are probed in the voltage domain with the accuracy of 20 ps by a newly developed electronics, and the data are collected by the novel trigger-less and reconfigurable data acquisition system. The hit-position and hit-time are reconstructed by the dedicated reconstruction methods based on the compressing sensing theory and the library of synchronized model signals. The solutions are subject to twelve patent applications. So far a time-of-flight resolution of ~120 ps (sigma) was achieved for a double-strip prototype with 30 cm field-of-view (FOV). It is by more than a factor of two better than TOF resolution achievable in current TOF-PET modalities and at the same time the FOV of 30 cm long prototype is significantly larger with respect to typical commercial PET devices. The Jagiellonian PET (J-PET) detector with plastic scintillators arranged axially possesses also another advantage. Its diagnostic chamber is free of any electronic devices and magnetic materials thus giving unique possibilities of combining J-PET with CT and J-PET with MRI for scanning the same part of a patient at the same time with both methods.

Keywords: PET-CT, PET-MRI, TOF-PET, scintillator

Procedia PDF Downloads 461
704 The Role of Social Media in the Rise of Islamic State in India: An Analytical Overview

Authors: Yasmeen Cheema, Parvinder Singh

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The evolution of Islamic State (acronym IS) has an ultimate goal of restoring the caliphate. IS threat to the global security is main concern of international community but has also raised a factual concern for India about the regular radicalization of IS ideology among Indian youth. The incident of joining Arif Ejaz Majeed, an Indian as ‘jihadist’ in IS has set strident alarm in law & enforcement agencies. On 07.03.2017, many people were injured in an Improvised Explosive Device (IED) blast on-board of Bhopal Ujjain Express. One perpetrator of this incident was killed in encounter with police. But, the biggest shock is that the conspiracy was pre-planned and the assailants who carried out the blast were influenced by the ideology perpetrated by the Islamic State. This is the first time name of IS has cropped up in a terror attack in India. It is a red indicator of violent presence of IS in India, which is spreading through social media. The IS have the capacity to influence the younger Muslim generation in India through its brutal and aggressive propaganda videos, social media apps and hatred speeches. It is a well known fact that India is on the radar of IS, as well on its ‘Caliphate Map’. IS uses Twitter, Facebook and other social media platforms constantly. Islamic State has used enticing videos, graphics, and articles on social media and try to influence persons from India & globally that their jihad is worthy. According to arrested perpetrator of IS in different cases in India, the most of Indian youths are victims to the daydreams which are fondly shown by IS. The dreams that the Muslim empire as it was before 1920 can come back with all its power and also that the Caliph and its caliphate can be re-established are shown by the IS. Indian Muslim Youth gets attracted towards these euphemistic ideologies. Islamic State has used social media for disseminating its poisonous ideology, recruitment, operational activities and for future direction of attacks. IS through social media inspired its recruits & lone wolfs to continue to rely on local networks to identify targets and access weaponry and explosives. Recently, a pro-IS media group on its Telegram platform shows Taj Mahal as the target and suggested mode of attack as a Vehicle Born Improvised Explosive Attack (VBIED). Islamic State definitely has the potential to destroy the Indian national security & peace, if timely steps are not taken. No doubt, IS has used social media as a critical mechanism for recruitment, planning and executing of terror attacks. This paper will therefore examine the specific characteristics of social media that have made it such a successful weapon for Islamic State. The rise of IS in India should be viewed as a national crisis and handled at the central level with efficient use of modern technology.

Keywords: ideology, India, Islamic State, national security, recruitment, social media, terror attack

Procedia PDF Downloads 201
703 Detecting Venomous Files in IDS Using an Approach Based on Data Mining Algorithm

Authors: Sukhleen Kaur

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In security groundwork, Intrusion Detection System (IDS) has become an important component. The IDS has received increasing attention in recent years. IDS is one of the effective way to detect different kinds of attacks and malicious codes in a network and help us to secure the network. Data mining techniques can be implemented to IDS, which analyses the large amount of data and gives better results. Data mining can contribute to improving intrusion detection by adding a level of focus to anomaly detection. So far the study has been carried out on finding the attacks but this paper detects the malicious files. Some intruders do not attack directly, but they hide some harmful code inside the files or may corrupt those file and attack the system. These files are detected according to some defined parameters which will form two lists of files as normal files and harmful files. After that data mining will be performed. In this paper a hybrid classifier has been used via Naive Bayes and Ripper classification methods. The results show how the uploaded file in the database will be tested against the parameters and then it is characterised as either normal or harmful file and after that the mining is performed. Moreover, when a user tries to mine on harmful file it will generate an exception that mining cannot be made on corrupted or harmful files.

Keywords: data mining, association, classification, clustering, decision tree, intrusion detection system, misuse detection, anomaly detection, naive Bayes, ripper

Procedia PDF Downloads 391
702 Parental Perceptions and Practices toward Childhood Asthma

Authors: Amani K. Abu-Shaheen, Abdullah Nofal, Humariya Heena

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Introduction: Parental perceptions and practices are important for improving the asthma outcomes in children; indeed, evidence shows that parents of asthmatic children harbor considerable misperceptions of the disease. Objective: To identify the prevalence of asthma and to investigate the perceptions and practices of parents toward asthma and its management in Saudi children. Methods: A two-stage cross-sectional survey of 2000 parents of children aged 3–15 years from schools located in all five districts of Riyadh province located in central Saudi Arabia, was conducted. Data collection was accomplished using a self-administered questionnaire based on information obtained from the literature. Results: Of 1450 children whose parents participated in the study, 600 had asthma, dyspnea, or chest allergy. The overall number of children with parental reports of ever having been diagnosed with asthma was 478 (32.9%). The majority of parents (321, 53.5%) believed that asthma was a hereditary disease. Of these parents, 361 (60.3%) were concerned about side effects of inhaled steroids, and 192 (32%) about development of dependency on asthma medications. Three hundred sixty seven (61.2%) parents reported that they could treat the asthma attack at home and almost 76% of parents went to pediatric emergency department during asthma attack. Conclusions: In this study, the overall prevalence of children whose parents reported that they were diagnosed with asthma was high (32.9%). Furthermore, parents of children with asthma had misperceptions regarding asthma and exhibited ineffective practices in its management. To improve asthma care and compliance, adequate education should be provided to parents.

Keywords: asthma, management, parents, quality of life

Procedia PDF Downloads 250
701 In-Cylinder Exhaust Heat Recovery of an I. C. Engine Using Water Injection

Authors: Jayakrishnan U.

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A concept of adding two strokes to a four stroke Otto or Diesel engine cycle presented here for the waste heat recovery in a four stroke internal combustion engine. Four stroke Diesel cycle and Otto cycle engines have very low thermal efficiency due to high amount of energy loss in exhaust and also on the cooling of the engine. It is estimated about 35 percent of fuel energy is lost in exhaust of engine and 30 percent in cooling of engine. So by modifying a four-stroke Otto or Diesel engine by adding two-stroke heat recovery steam cycle is presented here. Water injection is used to get an additional power stroke by partial compression of the exhaust gases at the end of third stroke in a four stroke I.C.Engine. It is the conversion of a four-stroke cycle to a six-stroke cycle. By taking a four stroke petrol engine of known dimensions, an ideal thermodynamic model is used to analyse and calculate the events of exhaust gas compression and following two strokes of water injection. By changing the exhaust valve closing timing during exhaust stroke and analysing it on various points, an optimum amount of exhaust gas re-compression and amount of water injection can be found for maximizing efficiency and fuel economy. It is achieved by changing the exhaust valve timing and finding an optimum amount of exhaust re-compression, maximizing the net mean effective pressure of the steam expansion stroke (MEPsteam). Specific fuel consumption of the engine also decreases increasing the fuel economy. The valve closing timings for maximum MEPsteam is limited by either 1 bar or dew point temperature of expansion gas or moisture mixture to avoid moisture formation. By modifying the four-stroke Otto or Diesel cycle by adding two water injection stroke has the potential to significantly increase the engine efficiency and fuel economy.

Keywords: internal combustion engine, engine efficiency, six-stroke cycle, water injection, specific fuel consumption

Procedia PDF Downloads 275
700 USBware: A Trusted and Multidisciplinary Framework for Enhanced Detection of USB-Based Attacks

Authors: Nir Nissim, Ran Yahalom, Tomer Lancewiki, Yuval Elovici, Boaz Lerner

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Background: Attackers increasingly take advantage of innocent users who tend to use USB devices casually, assuming these devices benign when in fact they may carry an embedded malicious behavior or hidden malware. USB devices have many properties and capabilities that have become the subject of malicious operations. Many of the recent attacks targeting individuals, and especially organizations, utilize popular and widely used USB devices, such as mice, keyboards, flash drives, printers, and smartphones. However, current detection tools, techniques, and solutions generally fail to detect both the known and unknown attacks launched via USB devices. Significance: We propose USBWARE, a project that focuses on the vulnerabilities of USB devices and centers on the development of a comprehensive detection framework that relies upon a crucial attack repository. USBWARE will allow researchers and companies to better understand the vulnerabilities and attacks associated with USB devices as well as providing a comprehensive platform for developing detection solutions. Methodology: The framework of USBWARE is aimed at accurate detection of both known and unknown USB-based attacks by a process that efficiently enhances the framework's detection capabilities over time. The framework will integrate two main security approaches in order to enhance the detection of USB-based attacks associated with a variety of USB devices. The first approach is aimed at the detection of known attacks and their variants, whereas the second approach focuses on the detection of unknown attacks. USBWARE will consist of six independent but complimentary detection modules, each detecting attacks based on a different approach or discipline. These modules include novel ideas and algorithms inspired from or already developed within our team's domains of expertise, including cyber security, electrical and signal processing, machine learning, and computational biology. The establishment and maintenance of the USBWARE’s dynamic and up-to-date attack repository will strengthen the capabilities of the USBWARE detection framework. The attack repository’s infrastructure will enable researchers to record, document, create, and simulate existing and new USB-based attacks. This data will be used to maintain the detection framework’s updatability by incorporating knowledge regarding new attacks. Based on our experience in the cyber security domain, we aim to design the USBWARE framework so that it will have several characteristics that are crucial for this type of cyber-security detection solution. Specifically, the USBWARE framework should be: Novel, Multidisciplinary, Trusted, Lightweight, Extendable, Modular and Updatable and Adaptable. Major Findings: Based on our initial survey, we have already found more than 23 types of USB-based attacks, divided into six major categories. Our preliminary evaluation and proof of concepts showed that our detection modules can be used for efficient detection of several basic known USB attacks. Further research, development, and enhancements are required so that USBWARE will be capable to cover all of the major known USB attacks and to detect unknown attacks. Conclusion: USBWARE is a crucial detection framework that must be further enhanced and developed.

Keywords: USB, device, cyber security, attack, detection

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699 Proposal of Optimality Evaluation for Quantum Secure Communication Protocols by Taking the Average of the Main Protocol Parameters: Efficiency, Security and Practicality

Authors: Georgi Bebrov, Rozalina Dimova

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In the field of quantum secure communication, there is no evaluation that characterizes quantum secure communication (QSC) protocols in a complete, general manner. The current paper addresses the problem concerning the lack of such an evaluation for QSC protocols by introducing an optimality evaluation, which is expressed as the average over the three main parameters of QSC protocols: efficiency, security, and practicality. For the efficiency evaluation, the common expression of this parameter is used, which incorporates all the classical and quantum resources (bits and qubits) utilized for transferring a certain amount of information (bits) in a secure manner. By using criteria approach whether or not certain criteria are met, an expression for the practicality evaluation is presented, which accounts for the complexity of the QSC practical realization. Based on the error rates that the common quantum attacks (Measurement and resend, Intercept and resend, probe attack, and entanglement swapping attack) induce, the security evaluation for a QSC protocol is proposed as the minimum function taken over the error rates of the mentioned quantum attacks. For the sake of clarity, an example is presented in order to show how the optimality is calculated.

Keywords: quantum cryptography, quantum secure communcation, quantum secure direct communcation security, quantum secure direct communcation efficiency, quantum secure direct communcation practicality

Procedia PDF Downloads 153
698 On the Design of a Secure Two-Party Authentication Scheme for Internet of Things Using Cancelable Biometrics and Physically Unclonable Functions

Authors: Behnam Zahednejad, Saeed Kosari

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Widespread deployment of Internet of Things (IoT) has raised security and privacy issues in this environment. Designing a secure two-factor authentication scheme between the user and server is still a challenging task. In this paper, we focus on Cancelable Biometric (CB) as an authentication factor in IoT. We show that previous CB-based scheme fail to provide real two-factor security, Perfect Forward Secrecy (PFS) and suffer database attacks and traceability of the user. Then we propose our improved scheme based on CB and Physically Unclonable Functions (PUF), which can provide real two-factor security, PFS, user’s unlinkability, and resistance to database attack. In addition, Key Compromise Impersonation (KCI) resilience is achieved in our scheme. We also prove the security of our proposed scheme formally using both Real-Or-Random (RoR) model and the ProVerif analysis tool. For the usability of our scheme, we conducted a performance analysis and showed that our scheme has the least communication cost compared to the previous CB-based scheme. The computational cost of our scheme is also acceptable for the IoT environment.

Keywords: IoT, two-factor security, cancelable biometric, key compromise impersonation resilience, perfect forward secrecy, database attack, real-or-random model, ProVerif

Procedia PDF Downloads 73
697 Phishing Detection: Comparison between Uniform Resource Locator and Content-Based Detection

Authors: Nuur Ezaini Akmar Ismail, Norbazilah Rahim, Norul Huda Md Rasdi, Maslina Daud

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A web application is the most targeted by the attacker because the web application is accessible by the end users. It has become more advantageous to the attacker since not all the end users aware of what kind of sensitive data already leaked by them through the Internet especially via social network in shake on ‘sharing’. The attacker can use this information such as personal details, a favourite of artists, a favourite of actors or actress, music, politics, and medical records to customize phishing attack thus trick the user to click on malware-laced attachments. The Phishing attack is one of the most popular attacks for social engineering technique against web applications. There are several methods to detect phishing websites such as Blacklist/Whitelist based detection, heuristic-based, and visual similarity-based detection. This paper illustrated a comparison between the heuristic-based technique using features of a uniform resource locator (URL) and visual similarity-based detection techniques that compares the content of a suspected phishing page with the legitimate one in order to detect new phishing sites based on the paper reviewed from the past few years. The comparison focuses on three indicators which are false positive and negative, accuracy of the method, and time consumed to detect phishing website.

Keywords: heuristic-based technique, phishing detection, social engineering and visual similarity-based technique

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696 Assessment of the Performance of Fly Ash Based Geo-Polymer Concrete under Sulphate and Acid Attack

Authors: Talakokula Visalakshi

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Concrete is the most commonly used construction material across the globe, its usage is second only to water. It is prepared using ordinary Portland cement whose production contributes to 5-8% of total carbon emission in the world. On the other hand the fly ash by product from the power plants is produced in huge quantities is termed as waste and disposed in landfills. In order to address the above issues mentioned, it is essential that other forms of binding material must be developed in place of cement to make concrete. The geo polymer concrete is one such alternative developed by Davidovits in 1980’s. Geopolymer do not form calcium-silicate hydrates for matrix formation and strength but undergo polycondensation of silica and alumina precursors to attain structural strength. Its setting mechanism depends upon polymerization rather than hydration. As a result it is able to achieve its strength in 3-5 days whereas concrete requires about a month to do the same. The objective of this research is to assess the performance of geopolymer concrete under sulphate and acid attack. The assessment is done based on the experiments conducted on geopolymer concrete. The expected outcomes include that if geopolymer concrete is more durable than normal concrete, then it could be a competitive replacement option of concrete and can lead to significant reduction of carbon foot print and have a positive impact on the environment. Fly ash based geopolymer concrete offers an opportunity to completely remove the cement content from concrete thereby making the concrete a greener and future construction material.

Keywords: fly ash, geo polymer, geopolymer concrete, construction material

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695 Estimation of Pressure Profile and Boundary Layer Characteristics over NACA 4412 Airfoil

Authors: Anwar Ul Haque, Waqar Asrar, Erwin Sulaeman, Jaffar S. M. Ali

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Pressure distribution data of the standard airfoils is usually used for the calibration purposes in subsonic wind tunnels. Results of such experiments are quite old and obtained by using the model in the spanwise direction. In this manuscript, pressure distribution over NACA 4412 airfoil model was presented by placing the 3D model in the lateral direction. The model is made of metal with pressure ports distributed longitudinally as well as in the lateral direction. The pressure model was attached to the floor of the tunnel with the help of the base plate to give the specified angle of attack to the model. Before the start of the experiments, the pressure tubes of the respective ports of the 128 ports pressure scanner are checked for leakage, and the losses due to the length of the pipes were also incorporated in the results for the specified pressure range. Growth rate maps of the boundary layer thickness were also plotted. It was found that with the increase in the velocity, the dynamic pressure distribution was also increased for the alpha seep. Plots of pressure distribution so obtained were overlapped with those obtained by using XFLR software, a low fidelity tool. It was found that at moderate and high angles of attack, the distribution of the pressure coefficients obtained from the experiments is high when compared with the XFLR ® results obtained along with the span of the wing. This under-prediction by XFLR ® is more obvious on the windward than on the leeward side.

Keywords: subsonic flow, boundary layer, wind tunnel, pressure testing

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694 An Approach towards Elementary Investigation on HCCI Technology

Authors: Jitendra Sharma

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Here a Homogeneous Charge is used as in a spark-ignited engine, but the charge is compressed to auto ignition as in a diesel. The main difference compared with the Spark Ignition (SI) engine is the lack of flame propagation and hence the independence from turbulence. Compared with the diesel engine. HCCI has a homogeneous charge and have no problems associated with soot and Nox but HC and CO were higher than in SI mode. It was not possible to achieve high IMEP (Indicated Mean Effective Pressure) values with HCCI. The Homogeneous charge compression ignition (HCCI) is an attractive technology because of its high efficiency and low emissions. However, HCCI lakes a direct combustion trigger making control of combustion timing challenging, especially during transients. To aid in HCCI engine control we present a simple model of the HCCI combustion process valid over a range of intake pressures, intake temperatures, equivalence ratios and engine speeds. HCCI a new combustion technology that may develop as an alternative to diesel engines with high efficiency and low Knox and particulate matter emissions. The homogenous charge compression ignition (HCCI) is a promising new engine technology that combines elements of the diesel and gasoline engine operating cycles. HCCI as a way to increase the efficiency of the gasoline engine. The attractive properties are increased fuel efficiency due to reduced throttling losses, increased expansion ratio and higher thermodynamic efficiency. With the advantages there are some mechanical limitations to the operation of the HCCI engine. The implementation of homogenous charge compression ignition (HCCI) to gasoline engines is constrained by many factors. The main drawback of HCCI is the absence of direct combustion timing control. Therefore all the right conditions for auto ignition have to be set before combustion starts. This paper describes the past and current research done on HCCI engine. Many research got considerable success in doing detailed modeling of HCCI combustion. This paper aims at studying the fundamentals of HCCI combustion, the strategy to control the limitation of HCCI engine.

Keywords: HCCI, diesel engine, combustion, elementary investigation

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693 Numerical Simulation of the Effect of Single and Dual Synthetic Jet on Stall Phenomenon On NACA (National Advisory Committee for Aeronautics) GA(W)-2 Airfoil

Authors: Abbasali Abouei Mehrizi, Hamid Hassanzadeh Afrouzi

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Reducing the drag force increases the efficiency of the aircraft and its better performance. Flow control methods delay the phenomenon of flow separation and consequently reduce the reversed flow phenomenon in the separation region and enhance the performance of the lift force while decreasing the drag force and thus improving the aircraft efficiency. Flow control methods can be divided into active and passive types. The use of synthetic jets actuator (SJA) used in this study for NACA GA (W) -2 airfoil is one of the active flow control methods to prevent stall phenomenon on the airfoil. In this research, the relevant airfoil in different angles of attack with and without jets has been compared by OpenFOAM. Also, after achieving the proper SJA position on the airfoil suction surface, the simultaneous effect of two SJAs has been discussed. It was found to have the best effect at 12% chord (C), close to the airfoil’s leading edge (LE). At 12% chord, SJA decreases the drag significantly with increasing lift, and also, the average lift increase was higher than other situations and was equal to 10.4%. The highest drag reduction was about 5% in SJA=0.25C. Then, due to the positive effects of SJA in the 12% and 25% chord regions, these regions were considered for applying dual jets in two post-stall angles of attack, i.e., 16° and 22°.

Keywords: active and passive flow control methods, computational fluid dynamics, flow separation, synthetic jet

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692 Removing Maturational Influences from Female Youth Swimming: The Application of Corrective Adjustment Procedures

Authors: Clorinda Hogan, Shaun Abbott, Mark Halaki, Marcela Torres Catiglioni, Goshi Yamauchi, Lachlan Mitchell, James Salter, Michael Romann, Stephen Cobley

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Introduction: Common annual age-group competition structures unintentionally introduce participation inequalities, performance (dis)advantages and selection biases due to the effect of maturational variation between youth swimmers. On this basis, there are implications for improving performance evaluation strategies. Therefore the aim was to: (1) To determine maturity timing distributions in female youth swimming; (2) quantify the relationship between maturation status and 100-m FC performance; (3) apply Maturational-based Corrective Adjustment Procedures (Mat-CAPs) for removal of maturational status performance influences. Methods: (1) Cross-sectional analysis of 663 female (10-15 years) swimmers who underwent assessment of anthropometrics (mass, height and sitting height) and estimations of maturity timing and offset. (2) 100-m front-crawl performance (seconds) was assessed at Australian regional, state, and national-level competitions between 2016-2020. To determine the relationship between maturation status and 100-m front-crawl performance, MO was plotted against 100-m FC performance time. The expected maturity status - performance relationship for females aged 10-15 years of age was obtained through a quadratic function (y = ax2 + bx + c) from unstandardized coefficients. The regression equation was subsequently used for Mat-CAPs. (3) Participants aged 10-13 years were categorised into maturity-offset categories. Maturity offset distributions for Raw (‘All’, ‘Top 50%’ & ‘Top 25%’) and Correctively Adjusted swim times were examined. Chi-square, Cramer’s V and ORs determined the occurrence of maturation biases for each age group and selection level. Results—: (1) Maturity timing distributions illustrated overrepresentation of ‘normative’ maturing swimmers (11.82 ± 0.40 years), with a descriptive shift toward the early maturing relative to the normative population. (2) A curvilinear relationship between maturity-offset and swim performance was identified (R2 = 0.53, P < 0.001) and subsequently utilised for Mat-CAPs. (3) Raw maturity offset categories identified partial maturation status skewing towards biologically older swimmers at 10/11 and 12 years, with effect magnitudes increasing in the ‘Top 50%’ and ‘25%’ of performance times. Following Mat-CAPs application, maturity offset biases were removed in similar age groups and selection levels. When adjusting performance times for maturity offset, Mat-CAPs was successful in mitigating against maturational biases until approximately 1-year post Peak Height Velocity. The overrepresentation of ‘normative’ maturing female swimmers contrasted with the substantial overrepresentation of ‘early’ maturing male swimmers found previously in 100-m front-crawl. These findings suggest early maturational timing is not advantageous in females, but findings associated with Aim 2, highlight how advanced maturational status remained beneficial to performance. Observed differences between female and male maturational biases may relate to the differential impact of physiological development during pubertal years. Females experience greater increases of fat mass and potentially differing changes in body shape which can negatively affect swim performance. Conclusions: Transient maturation status-based participation and performance advantages were apparent within a large sample of Australian female youth 100-m FC swimmers. By removing maturity status performance biases within female youth swimming, Mat-CAPs could help improve participation experiences and the accuracy of identifying genuinely skilled female youth swimmers.

Keywords: athlete development, long-term sport participation, performance evaluation, talent identification, youth competition

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691 Off-Policy Q-learning Technique for Intrusion Response in Network Security

Authors: Zheni S. Stefanova, Kandethody M. Ramachandran

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With the increasing dependency on our computer devices, we face the necessity of adequate, efficient and effective mechanisms, for protecting our network. There are two main problems that Intrusion Detection Systems (IDS) attempt to solve. 1) To detect the attack, by analyzing the incoming traffic and inspect the network (intrusion detection). 2) To produce a prompt response when the attack occurs (intrusion prevention). It is critical creating an Intrusion detection model that will detect a breach in the system on time and also challenging making it provide an automatic and with an acceptable delay response at every single stage of the monitoring process. We cannot afford to adopt security measures with a high exploiting computational power, and we are not able to accept a mechanism that will react with a delay. In this paper, we will propose an intrusion response mechanism that is based on artificial intelligence, and more precisely, reinforcement learning techniques (RLT). The RLT will help us to create a decision agent, who will control the process of interacting with the undetermined environment. The goal is to find an optimal policy, which will represent the intrusion response, therefore, to solve the Reinforcement learning problem, using a Q-learning approach. Our agent will produce an optimal immediate response, in the process of evaluating the network traffic.This Q-learning approach will establish the balance between exploration and exploitation and provide a unique, self-learning and strategic artificial intelligence response mechanism for IDS.

Keywords: cyber security, intrusion prevention, optimal policy, Q-learning

Procedia PDF Downloads 203
690 Rapid Algorithm for GPS Signal Acquisition

Authors: Fabricio Costa Silva, Samuel Xavier de Souza

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A Global Positioning System (GPS) receiver is responsible to determine position, velocity and timing information by using satellite information. To get this information are necessary to combine an incoming and a locally generated signal. The procedure called acquisition need to found two information, the frequency and phase of the incoming signal. This is very time consuming, so there are several techniques to reduces the computational complexity, but each of then put projects issues in conflict. I this papers we present a method that can reduce the computational complexity by reducing the search space and paralleling the search.

Keywords: GPS, acquisition, complexity, parallelism

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689 Rapid Parallel Algorithm for GPS Signal Acquisition

Authors: Fabricio Costa Silva, Samuel Xavier de Souza

Abstract:

A Global Positioning System (GPS) receiver is responsible to determine position, velocity and timing information by using satellite information. To get this information's are necessary to combine an incoming and a locally generated signal. The procedure called acquisition need to found two information, the frequency and phase of the incoming signal. This is very time consuming, so there are several techniques to reduces the computational complexity, but each of then put projects issues in conflict. I this papers we present a method that can reduce the computational complexity by reducing the search space and paralleling the search.

Keywords: GPS, acquisition, low complexity, parallelism

Procedia PDF Downloads 455
688 Aerodynamic Modelling of Unmanned Aerial System through Computational Fluid Dynamics: Application to the UAS-S45 Balaam

Authors: Maxime A. J. Kuitche, Ruxandra M. Botez, Arthur Guillemin

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As the Unmanned Aerial Systems have found diverse utilities in both military and civil aviation, the necessity to obtain an accurate aerodynamic model has shown an enormous growth of interest. Recent modeling techniques are procedures using optimization algorithms and statistics that require many flight tests and are therefore extremely demanding in terms of costs. This paper presents a procedure to estimate the aerodynamic behavior of an unmanned aerial system from a numerical approach using computational fluid dynamic analysis. The study was performed using an unstructured mesh obtained from a grid convergence analysis at a Mach number of 0.14, and at an angle of attack of 0°. The flow around the aircraft was described using a standard k-ω turbulence model. Thus, the Reynold Averaged Navier-Stokes (RANS) equations were solved using ANSYS FLUENT software. The method was applied on the UAS-S45 designed and manufactured by Hydra Technologies in Mexico. The lift, the drag, and the pitching moment coefficients were obtained at different angles of attack for several flight conditions defined in terms of altitudes and Mach numbers. The results obtained from the Computational Fluid Dynamics analysis were compared with the results obtained by using the DATCOM semi-empirical procedure. This comparison has indicated that our approach is highly accurate and that the aerodynamic model obtained could be useful to estimate the flight dynamics of the UAS-S45.

Keywords: aerodynamic modelling, CFD Analysis, ANSYS FLUENT, UAS-S45

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687 Understanding the Effect of Material and Deformation Conditions on the “Wear Mode Diagram”: A Numerical Study

Authors: A. Mostaani, M. P. Pereira, B. F. Rolfe

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The increasing application of Advanced High Strength Steel (AHSS) in the automotive industry to fulfill crash requirements has introduced higher levels of wear in stamping dies and parts. Therefore, understanding wear behaviour in sheet metal forming is of great importance as it can help to reduce the high costs currently associated with tool wear. At the contact between the die and the sheet, the tips of hard tool asperities interact with the softer sheet material. Understanding the deformation that occurs during this interaction is important for our overall understanding of the wear mechanisms. For these reasons, the scratching of a perfectly plastic material by a rigid indenter has been widely examined in the literature; with finite element modelling (FEM) used in recent years to further understand the behaviour. The ‘wear mode diagram’ has been commonly used to classify the deformation regime of the soft work-piece during scratching, into three modes: ploughing, wedge formation, and cutting. This diagram, which is based on 2D slip line theory and upper bound method for perfectly plastic work-piece and rigid indenter, relates different wear modes to attack angle and interfacial strength. This diagram has been the basis for many wear studies and wear models to date. Additionally, it has been concluded that galling is most likely to occur during the wedge formation mode. However, there has been little analysis in the literature of how the material behaviour and deformation conditions associated with metal forming processes influence the wear behaviour. Therefore, the first aim of this work is first to use a commercial FEM package (Abaqus/Explicit) to build a 3D model to capture wear modes during scratching with indenters with different attack angles and different interfacial strengths. The second goal is to utilise the developed model to understand how wear modes might change in the presence of bulk deformation of the work-piece material as a result of the metal forming operation. Finally, the effect of the work-piece material properties, including strain hardening, will be examined to understand how these influence the wear modes and wear behaviour. The results show that both strain hardening and substrate deformation can change the critical attack angle at which the wedge formation regime is activated.

Keywords: finite element, pile-up, scratch test, wear mode

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686 Direct and Indirect Impacts of Predator Conflict in Kanha National Park, India

Authors: Diane H. Dotson, Shari L. Rodriguez

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Habitat for predators is on the decline worldwide, which often brings humans and predators into conflict over remaining shared space and common resources. While the direct impacts of human predator conflict on humans (i.e., attacks on livestock or humans resulting in injury or death) are well documented, the indirect impacts of conflict on humans (i.e., downstream effects such as fear, stress, opportunity costs, PTSD) have not been addressed. We interviewed 437 people living in 54 villages on the periphery of Kanha National Park, India, to assess the amount and severity of direct and indirect impacts of predator conflict. ​While 58% of livestock owners believed that predator attacks on livestock guards occurred frequently and 62% of those who collect forest products believed that predator attacks on those collecting occurred frequently, less than 20% of all participants knew of someone who had experienced an attack. Data related to indirect impacts suggest that such impacts are common; 76% of participants indicated they were afraid a predator will physically injure them. Livestock owners reported that livestock guarding took time away from their primary job (61%) and getting enough sleep (73%), and believed that it increased their vulnerability to illnesses (80%). These results suggest that the perceptions of risk of predator attack are likely inflated, yet the costs of human predator impacts may be substantially higher than previously estimated, particularly related to human well-being, making the implementation of appropriate and effective conservation and conflict mitigation strategies and policies increasingly urgent.

Keywords: direct impacts, indirect impacts, human-predator conflict, India

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685 Association between Caries Status of First Permanent Molar with Oral Health Care Practice in Children Aged 9-12 Years in Lubuk Kilangan, Padang City

Authors: Cytha Nilam Chairani, Ditha Noviantika, Hidayati Amir, Nurul Khairiyah, Siti Rahmadita, Fadila Khairani

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Background: Dental caries is one of the most common diseases with high prevalence in children. The first permanent molar (FPM) has an essential role in establishing the occlusion. Nevertheless, FPM is very prone to caries because of various factors, such as their anatomical structure and early emergence in oral cavity. It is due to the little knowledge from parents and children regarding the timing of emergence of FPM in oral cavity which is still considered as primary teeth. Furthermore, the lack of knowledge from parents and children may affect their oral hygiene practice resulting to carious process. Objective: The aim of this study was to assess the status of FPM caries and its association with children’s oral hygiene practice in 9-12-year-old school children in Lubuk Kilangan Community Health Centre, Padang City. Methods: A cross-sectional study was performed in 50 school children (9-12 years old) using random sampling technique from two randomly selected schools in Lubuk Kilangan Community Health Centre, Padang City. A questionnaire was developed from other studies consisting of four closed ended questions regarding oral health practice. The data obtained were analyzed statistically using Mann-Whitney Test to assess the status of FPM caries and its association with children’s oral hygiene practice. Results: The results showed that 32% of children had FPMs sound and the remaining 68% had FPMs carious which were grouped into 1-2 FPMs carious (60%) and 3-4 FPMs carious (8%). The caries status of mandibular FPM (64%) was higher compared to maxillary FPM (10%). Conclusion: There was significant association in subject who did not visit dentist in the last 6 months which had more carious FPMs compared to subject who visited dentist (p < 0.05). There was no significant association between the status of FPM caries and knowledge of the timing eruption of FPM, oral hygiene instruction from parents and tooth brushing (p > 0.05).

Keywords: dental caries, children, first permanent molar, oral hygiene practice

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684 Controlling Cocoa Pod Borer, Conopomorpha cramerella (Snell.) and Cost Analysis Production at Cacao Plantation

Authors: Alam Anshary, Flora Pasaru, Shahabuddin

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The Cocoa Pod Borer (CPB), Conopomorpha cramerella (Snell.) is present on most of the larger cocoa producing islands in Indonesia. Various control measures CPB has been carried out by the farmers, but the results have not been effective. This study aims to determine the effect of application of Beauveria bassiana treatments and pruning technique to the control of CPB in the cocoa plantation people. Research using completely randomized design with 4 treatments and 3 replications, treatment consists of B.bassiana, Pruning, B. bassiana+pruning (Bb + Pr), as well as the control. The results showed that the percentage of PBK attack on cocoa pods in treatment (Bb + Pr) 3.50% the lowest compared to other treatments. CPB attack percentage in treatment B.bassiana 6.15%; pruning 8.75%, and 15.20% control. Results of the analysis of production estimates, the known treatments (Bb + Pr) have the highest production (1.95 tonnes / ha). The model results estimated production is Y= 0,20999 + 0,53968X1 + 0,34298X2+ 0,31410X3 + 0,35629X4 + 0,08345X5 + 0,29732X6. Farm production costs consist of fixed costs and variable costs, fixed costs are costs incurred by the farmer that the size does not affect the results, such as taxes and depreciation of production equipment. Variable costs are costs incurred by farmers who used up in one year cocoa farming activities. The cost of production in farming cocoa without integrated techniques control of CPB is Rp. 9.205.550 million/ha, while the cost of production with integrated techniques control is Rp. 6.666.050 million/ha.

Keywords: cacao, cocoa pod borer, pruning, Beauveria bassiana, production costs

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683 Feature Based Unsupervised Intrusion Detection

Authors: Deeman Yousif Mahmood, Mohammed Abdullah Hussein

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The goal of a network-based intrusion detection system is to classify activities of network traffics into two major categories: normal and attack (intrusive) activities. Nowadays, data mining and machine learning plays an important role in many sciences; including intrusion detection system (IDS) using both supervised and unsupervised techniques. However, one of the essential steps of data mining is feature selection that helps in improving the efficiency, performance and prediction rate of proposed approach. This paper applies unsupervised K-means clustering algorithm with information gain (IG) for feature selection and reduction to build a network intrusion detection system. For our experimental analysis, we have used the new NSL-KDD dataset, which is a modified dataset for KDDCup 1999 intrusion detection benchmark dataset. With a split of 60.0% for the training set and the remainder for the testing set, a 2 class classifications have been implemented (Normal, Attack). Weka framework which is a java based open source software consists of a collection of machine learning algorithms for data mining tasks has been used in the testing process. The experimental results show that the proposed approach is very accurate with low false positive rate and high true positive rate and it takes less learning time in comparison with using the full features of the dataset with the same algorithm.

Keywords: information gain (IG), intrusion detection system (IDS), k-means clustering, Weka

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682 The Ethio-Eritrea Claims Commission on Use of Force: Issue of Self-Defense or Violation of Sovereignty

Authors: Isaias Teklia Berhe

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A decision that deals with international disputes, be it arbitral or judicial, has to properly reflect objectivity and coherence with existing rules of international law. This paper shows the decision of the Ethio-Eritrea Claims Commission on the jus ad bellum case is bereft of objectivity and coherence, which contributed a disservice to international law on many aspects. The Commission’s decision that holds Eritrea in contravention to Art 2(4) of the UN Charter based on Ethiopia’s contention is flawed. It fails to consider: the illegitimacy of an actual authority established over contested territory through hostile acts, the proper determination of effectivites under international law, the sanctity of colonially determined boundaries, Ethiopia’s prior firm political recognition and undergirds to respect colonial boundary, and Ethio-Eritrea Border Commission’s decision. The paper will also argue that the Commission confused Eritrea’s right of self-defense with the rule against the non-use of force to settle territorial disputes; wherefore its decision sanitizes or sterilizes unlawful change of territory resulted through unlawful use of force to the effect of advantaging aggressions. The paper likewise argues that the decision is so sacrilegious that it disregards the ossified legal finality of colonial boundaries. Moreover, its approach toward armed attack does not reflect the peculiarity of the jus ad bellum case rather it brings about definitional uncertainties and sustains the perception that the law on self-defense is unsettled.

Keywords: armed attack, Eritrea, Ethiopia, self-defense, territorial integrity, use of force

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681 Effect of Injection Pressure and Fuel Injection Timing on Emission and Performance Characteristics of Karanja Biodiesel and its Blends in CI Engine

Authors: Mohan H., C. Elajchet Senni

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In the present of high energy consumption in every sphere of life, renewable energy sources are emerging as alternative to conventional fuels for energy security, mitigating green house gas emission and climate change. There has been a world wide interest in searching for alternatives to petroleum derived fuels due to their depletion as well as due to the concern for the environment. Vegetable oils have capability to solve this problem because they are renewable and lead to reduction in environmental pollution. But high smoke emission and lower thermal efficiency are the main problems associated with the use of neat vegetable oils in diesel engines. In the present work, performance, combustion and emission characteristics of CI engine fuelled with 20% by vol. methyl esters mixed with Karanja seed Oil, and Fuel injection pressures of 200 bar and 240 bar, injection timings (21°,23° and 25° BTDC) and Proportion B20 diesel respectively. Vegetable oils have capability to solve this problem because they are renewable and lead to reduction in environmental pollution. But, high smoke emission and lower thermal efficiency are the main problems associated with the use of neat vegetable oils in diesel engines. In the present work, performance, combustion and emission characteristics of CI engine fuelled with 20% by vol. methyl esters mixed with Karanja seed Oil, and Fuel injection pressures of 200 bar and 240 bar ,Injection timings (21°,23° and 25° BTDC) and Proportion B20 diesel respectively. Various performance, combustion and emission characteristics such as thermal efficiency, and brake specific fuel consumption, maximum cylinder pressure, instantaneous heat release, cumulative heat release with respect to crank angle, ignition lag, combustion duration, HC, NOx, CO, exhaust temperature and smoke intensity were measured.

Keywords: karanja oil, injection pressure, injection timing, karanja oil methyl ester

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680 Haematological Correlates of Ischemic Stroke and Transient Ischemic Attack: Lessons Learned

Authors: Himali Gunasekara, Baddika Jayaratne

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Haematological abnormalities are known to cause Ischemic Stroke or Transient Ischemic Attack (TIA). The identification of haematological correlates plays an important role in a management and secondary prevention. The objective of this study was to describe haematological correlates of stroke and their association between stroke profile. The haematological correlates screened were Lupus Anticoagulant, Dysfibroginemia, Paroxysmal nocturnal haemoglobinurea (PNH), Sickle cell disease, Systemic Lupus Erythematosis (SLE) and Myeloploriferative Neoplasms (MPN). A cross sectional descriptive study was conducted in a sample of 152 stroke patients referred to haematology department of National Hospital of Sri Lanka for thrombophilia screening. Different tests were performed to assess each hematological correlate. Diluted Russels Viper Venom Test and Kaolin clotting time were done to assess Lupus anticoagulant. Full blood count (FBC), blood picture, Sickling test and High Performance Liquid Chromatography were the tests used for detection of Sickle cell disease. Paroxysmal nocturnal haemoglobinurea was assessed by FBC, blood picture, Ham test and Flowcytometry. FBC, blood picture, Janus Kinase 2 (V617F) mutation analysis, erythropoietin level and bone marrow examination were done to look for the Myeloproliferative neoplasms. Dysfibrinogenaemia was assessed by TT, fibrinogen antigen test, clot observation and clauss test. Anti nuclear antibody test was done to look for systemic lupus erythematosis. Among study sample, 134 patients had strokes and only 18 had TIA. The recurrence of stroke/TIA was observed in 13.2% of patients. The majority of patients (94.7%) have had radiological evidence of thrombotic event. One fourth of patients had past thrombotic events while 12.5% had family history of thrombosis. Out of haematological correlates screened, Lupus anticoagulant was the commonest haematological correlate (n=16 ) and dysfibrigonaemia(n=11 ) had the next high prevalence. One patient was diagnosed with Essential thrombocythaemia and one with SLE. None of the patients were positive for screening tests done for sickle cell disease and PNH. The Haematological correlates were identified in 19% of our study sample. Among stroke profile only presence of past thrombotic history was statistically significantly associated with haematological disorders (P= 0.04). Therefore, hematological disorders appear to be an important factor in etiological work-up of stroke patients particularly in patients with past thrombotic events.

Keywords: stroke, transient ischemic attack, hematological correlates, hematological disorders

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679 Effect of Wavy Leading-Edges on Wings in Different Planetary Atmospheres

Authors: Vatasta Koul, Ayush Gupta, Vaibhav Sharma, Rajesh Yadav

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Today we are unmarking the secrets of the universe by exploring different stars and planets and most of the space exploration is done by unmanned space robots. In addition to our planet Earth, there are pieces of evidence that show other astronomical objects in our solar system such as Venus, Mars, Saturn’s moon Titan and Uranus support the flight of fixed wing air vehicles. In this paper, we take forward the concept of presence of large rounded tubercles along the leading edge of a wing and use it as a passive flow control device that will help in improving its aerodynamic performance and maneuverability. Furthermore, in this research, aerodynamic measurements and performance analysis of wavy leading tubercles on the fixed wings at 5-degree angle of attack are carried out after determination of the flow conditions on the selected planetary bodies. Wavelength and amplitude for the sinusoidal modifications on the leading edge are analyzed and simulations are carried out for three-dimensional NACA 0012 airfoil maintaining unity AR (Aspect Ratio). Tubercles have consistently demonstrated the ability to delay and decrease the severity of stall as per the studies were done in the Earth’s atmosphere. Implementing the same design on the leading edges of Micro-Air Vehicles (MAVs) and UAVs could make these aircrafts more stable over a greater range of angles of attack in different planetary environments of our solar system.

Keywords: amplitude, NACA0012, tubercles, unmanned space robots

Procedia PDF Downloads 113
678 Computational Analysis of Cavity Effect over Aircraft Wing

Authors: P. Booma Devi, Dilip A. Shah

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This paper seeks the potentials of studying aerodynamic characteristics of inward cavities called dimples, as an alternative to the classical vortex generators. Increasing stalling angle is a greater challenge in wing design. But our examination is primarily focused on increasing lift. In this paper, enhancement of lift is mainly done by introduction of dimple or cavity in a wing. In general, aircraft performance can be enhanced by increasing aerodynamic efficiency that is lift to drag ratio of an aircraft wing. Efficiency improvement can be achieved by improving the maximum lift co-efficient or by reducing the drag co-efficient. At the time of landing aircraft, high angle of attack may lead to stalling of aircraft. To avoid this kind of situation, increase in the stalling angle is warranted. Hence, improved stalling characteristic is the best way to ease landing complexity. Computational analysis is done for the wing segment made of NACA 0012. Simulation is carried out for 30 m/s free stream velocity over plain airfoil and different types of cavities. The wing is modeled in CATIA V5R20 and analyses are carried out using ANSYS CFX. Triangle and square shapes are used as cavities for analysis. Simulations revealed that cavity placed on wing segment shows an increase of maximum lift co-efficient when compared to normal wing configuration. Flow separation is delayed at downstream of the wing by the presence of cavities up to a particular angle of attack.

Keywords: lift, drag reduce, square dimple, triangle dimple, enhancement of stall angle

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