Search results for: pitch angle control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 11897

Search results for: pitch angle control

9617 Stack Overflow Detection and Prevention on Operating Systems Using Machine Learning and Control-Flow Enforcement Technology

Authors: Cao Jiayu, Lan Ximing, Huang Jingjia, Burra Venkata Durga Kumar

Abstract:

The first virus to attack personal computers was born in early 1986, called C-Brain, written by a pair of Pakistani brothers. In those days, people still used dos systems, manipulating computers with the most basic command lines. In the 21st century today, computer performance has grown geometrically. But computer viruses are also evolving and escalating. We never stop fighting against security problems. Stack overflow is one of the most common security vulnerabilities in operating systems. It may result in serious security issues for an operating system if a program in it has a vulnerability with administrator privileges. Certain viruses change the value of specific memory through a stack overflow, allowing computers to run harmful programs. This study developed a mechanism to detect and respond to time whenever a stack overflow occurs. We demonstrate the effectiveness of standard machine learning algorithms and control flow enforcement techniques in predicting computer OS security using generating suspicious vulnerability functions (SVFS) and associated suspect areas (SAS). The method can minimize the possibility of stack overflow attacks occurring.

Keywords: operating system, security, stack overflow, buffer overflow, machine learning, control-flow enforcement technology

Procedia PDF Downloads 105
9616 Pragmatic Analysis of the Effectiveness of a Power Conditioning Device (DC-DC Converters) in a Simple Photovoltaics System

Authors: Asowata Osamede

Abstract:

Solar radiation provides the largest renewable energy potential on earth and photovoltaics (PV) are considered a promising technological solution to support the global transformation to a low-carbon economy and reduce dependence on fossil fuels. The aim of this paper is to evaluate the efficiency of power conditioning devices with a focus on the Buck and Boost DC-DC converters (12 V, 24 V and 48 V) in a basic off grid PV system with a varying load profile. This would assist in harnessing more of the available solar energy. The practical setup consists of a PV panel that is set to an orientation angle of 0º N, with corresponding tilt angles. Preliminary results, which include data analysis showing the power loss in the system and efficiency, indicate that the 12V DC-DC converter coupled with the load profile had the highest efficiency for a latitude of 26º S throughout the year.

Keywords: poly-crystalline PV panels, DC-DC converters, tilt and orientation angles, direct solar radiation, load profile

Procedia PDF Downloads 149
9615 MRI Quality Control Using Texture Analysis and Spatial Metrics

Authors: Kumar Kanudkuri, A. Sandhya

Abstract:

Typically, in a MRI clinical setting, there are several protocols run, each indicated for a specific anatomy and disease condition. However, these protocols or parameters within them can change over time due to changes to the recommendations by the physician groups or updates in the software or by the availability of new technologies. Most of the time, the changes are performed by the MRI technologist to account for either time, coverage, physiological, or Specific Absorbtion Rate (SAR ) reasons. However, giving properly guidelines to MRI technologist is important so that they do not change the parameters that negatively impact the image quality. Typically a standard American College of Radiology (ACR) MRI phantom is used for Quality Control (QC) in order to guarantee that the primary objectives of MRI are met. The visual evaluation of quality depends on the operator/reviewer and might change amongst operators as well as for the same operator at various times. Therefore, overcoming these constraints is essential for a more impartial evaluation of quality. This makes quantitative estimation of image quality (IQ) metrics for MRI quality control is very important. So in order to solve this problem, we proposed that there is a need for a robust, open-source, and automated MRI image control tool. The Designed and developed an automatic analysis tool for measuring MRI image quality (IQ) metrics like Signal to Noise Ratio (SNR), Signal to Noise Ratio Uniformity (SNRU), Visual Information Fidelity (VIF), Feature Similarity (FSIM), Gray level co-occurrence matrix (GLCM), slice thickness accuracy, slice position accuracy, High contrast spatial resolution) provided good accuracy assessment. A standardized quality report has generated that incorporates metrics that impact diagnostic quality.

Keywords: ACR MRI phantom, MRI image quality metrics, SNRU, VIF, FSIM, GLCM, slice thickness accuracy, slice position accuracy

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9614 Strategy and Maze Surgery (Atrial fibrillation Surgery)

Authors: Shirin Jalili, Ramin Ghasemi Shayan

Abstract:

Atrial fibrillation is the foremost common arrhythmia around the world, with expanding recurrence famous with age. Thromboembolic occasions and strokes are the number one cause of mortality and morbidity. For patients who don't react to restorative treatment for rate and beat control, the maze method offers an elective treatment mediation. pharmaco-medical treatment for atrial fibrillation is pointed at the control of rate or cadence, intrusive treatment for atrial fibrillation is pointed at cadence control. An obtrusive approach may comprise of percutaneous catheter treatment, surgery, or a crossover approach. Since the maze method is recognized as the foremost successful way to dispense with AF, combining the maze strategy amid major cardiac surgeries has been received in clinical hone. the maze strategy, moreover known as Cox¬maze iii or the ‘cut¬and¬sew’ method, involves making different incisions within the atria to make an arrangement of scars that dispose of each potential zone of re¬entry. The electrical drive is constrained through a maze of scars that coordinates the electrical drive from the sinus node to the av node. By settling the headstrong period between ranges of scar, re¬entry is disposed of. in this article, we evaluate the Maze surgery method that's the surgical method of choice for the treatment of restorative atrial fibrillation.

Keywords: atrial fibrillation, congenital heart disease, procedure, maze surgery, treatment

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9613 Experimental Analysis of Tuned Liquid Damper (TLD) with Embossments Subject to Random Excitation

Authors: Mohamad Saberi, Arash Sohrabi

Abstract:

Tuned liquid damper is one the passive structural control ways which has been used since mid-1980 decade for seismic control in civil engineering. This system is made of one or many tanks filled with fluid, mostly water that installed on top of the high raised structure and used to prevent structure vibration. In this article we will show how to make seismic table contain TLD system and analysis the result of using this system in our structure. Results imply that when frequency ratio approaches 1 this system can perform its best in both dissipate energy and increasing structural damping. And also results of these serial experiments are proved compatible with Hunzer linear theory behaviour.

Keywords: TLD, seismic table, structural system, Hunzer linear behaviour

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9612 Applying Sliding Autonomy for a Human-Robot Team on USARSim

Authors: Fang Tang, Jacob Longazo

Abstract:

This paper describes a sliding autonomy approach for coordinating a team of robots to assist the human operator to accomplish tasks while adapting to new or unexpected situations by requesting help from the human operator. While sliding autonomy has been well studied in the context of controlling a single robot. Much work needs to be done to apply sliding autonomy to a multi-robot team, especially human-robot team. Our approach aims at a hierarchical sliding control structure, with components that support human-robot collaboration. We validated our approach in the USARSim simulation and demonstrated that the human-robot team's overall performance can be improved under the sliding autonomy control.

Keywords: sliding autonomy, multi-robot team, human-robot collaboration, USARSim

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9611 Calculation of Stress Intensity Factors in Rotating Disks Containing 3D Semi-Elliptical Cracks

Authors: Mahdi Fakoor, Seyed Mohammad Navid Ghoreishi

Abstract:

Initiation and propagation of cracks may cause catastrophic failures in rotating disks, and hence determination of fracture parameter in rotating disks under the different working condition is very important issue. In this paper, a comprehensive study of stress intensity factors in rotating disks containing 3D semi-elliptical cracks under the different working condition is investigated. In this regard, after verification of modeling and analytical procedure, the effects of mechanical properties, rotational velocity, and orientation of cracks on Stress Intensity Factors (SIF) in rotating disks under centrifugal loading are investigated. Also, the effects of using composite patch in reduction of SIF in rotating disks are studied. By that way, the effects of patching design variables like mechanical properties, thickness, and ply angle are investigated individually.

Keywords: stress intensity factor, semi-elliptical crack, rotating disk, finite element analysis (FEA)

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9610 Machine Learning-Based Techniques for Detecting and Mitigating Cyber-attacks on Automatic Generation Control in Smart Grids

Authors: Sami M. Alshareef

Abstract:

The rapid growth of smart grid technology has brought significant advancements to the power industry. However, with the increasing interconnectivity and reliance on information and communication technologies, smart grids have become vulnerable to cyber-attacks, posing significant threats to the reliable operation of power systems. Among the critical components of smart grids, the Automatic Generation Control (AGC) system plays a vital role in maintaining the balance between generation and load demand. Therefore, protecting the AGC system from cyber threats is of paramount importance to maintain grid stability and prevent disruptions. Traditional security measures often fall short in addressing sophisticated and evolving cyber threats, necessitating the exploration of innovative approaches. Machine learning, with its ability to analyze vast amounts of data and learn patterns, has emerged as a promising solution to enhance AGC system security. Therefore, this research proposal aims to address the challenges associated with detecting and mitigating cyber-attacks on AGC in smart grids by leveraging machine learning techniques on automatic generation control of two-area power systems. By utilizing historical data, the proposed system will learn the normal behavior patterns of AGC and identify deviations caused by cyber-attacks. Once an attack is detected, appropriate mitigation strategies will be employed to safeguard the AGC system. The outcomes of this research will provide power system operators and administrators with valuable insights into the vulnerabilities of AGC systems in smart grids and offer practical solutions to enhance their cyber resilience.

Keywords: machine learning, cyber-attacks, automatic generation control, smart grid

Procedia PDF Downloads 74
9609 Performance Comparison of Reactive, Proactive and Hybrid Routing Protocols in Wireless Ad Hoc Networks

Authors: Kumar Manoj, Ramesh Kumar, Kumari Arti, Kumar Prashant

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 analyses these routing protocols by extensive simulations in OPNET simulator and show that how 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, data traffic sent, throughput, retransmission attempts.

Keywords: MANET, AODV, DSDV, DSR, ZRP

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9608 The MicroRNA-2110 Suppressed Cell Proliferation and Migration Capacity in Hepatocellular Carcinoma Cells

Authors: Pelin Balcik Ercin

Abstract:

Introduction: ZEB transcription factor family member ZEB2, has a role in epithelial to mesenchymal transition during development and metastasis. The altered circulating extracellular miRNAs expression is observed in diseases, and extracellular miRNAs have an important role in cancer cell microenvironment. In ChIP-Seq study, the expression of miR-2110 was found to be regulated by ZEB2. In this study, the effects of miR2110 on cell proliferation and migration of hepatocellular carcinoma (HCC) cells were examined. Material and Methods: SNU398 cells transfected with mimic miR2110 (20nM) (HMI0375, Sigma-Aldrich) and negative control miR (HMC0002, Sigma-Aldrich). MicroRNA isolation was accomplished with miRVANA isolation kit according to manufacturer instructions. cDNA synthesis was performed expression, respectively, and calibrated with Ct of controls. The real-time quantitative PCR (RT-qPCR) reaction was performed using the TaqMan Fast Advanced Master Mix (Thermo Sci.). Ct values of miR2110 were normalized to miR-186-5p and miR16-5p for the intracellular gene. Cell proliferation analysis was analyzed with the xCELLigence RTCA System. Wound healing assay was analyzed with the ImageJ program and relative fold change calculated. Results: The mimic-miR-2110 transfected SNU398 cells nearly nine-fold (log2) more miR-2110 expressed compared to negative control transfected cells. The mimic-miR-2110 transfected HCC cell proliferation significantly inhibited compared to the negative control cells. Furthermore, miR-2110-SNU398 cell migration capacity was relatively four-fold decreased compared to negative control-miR-SNU398 cells. Conclusion: Our results suggest the miR-2110 inhibited cell proliferation and also miR-2110 negatively affect cell migration compared to control groups in HCC cells. These data suggest the complexity of microRNA EMT transcription factors regulation. These initial results are pointed out the predictive biomarker capacity of miR-2110 in HCC.

Keywords: epithelial to mesenchymal transition, EMT, hepatocellular carcinoma cells, micro-RNA-2110, ZEB2

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9607 Role of Self-Concept in the Relationship between Emotional Abuse and Mental Health of Employees in the North West Province, South Africa

Authors: L. Matlawe, E. S. Idemudia

Abstract:

The stability is an important topic to plan and manage the energy in the microgrids as the same as the conventional power systems. The voltage and frequency stability is one of the most important issues recently studied in microgrids. The objectives of this paper are the modeling and designing of the components and optimal controllers for the voltage and frequency control of the AC/DC hybrid microgrid under the different disturbances. Since the PI controllers have the advantages of simple structure and easy implementation, so they were designed and modeled in this paper. The harmony search (HS) algorithm is used to optimize the controllers’ parameters. According to the achieved results, the PI controllers have a good performance in voltage and frequency control of the microgrid.

Keywords: emotional abuse, employees, mental health, self-concept

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9606 Optimal Mitigation of Slopes by Probabilistic Methods

Authors: D. De-León-Escobedo, D. J. Delgado-Hernández, S. Pérez

Abstract:

A probabilistic formulation to assess the slopes safety under the hazard of strong storms is presented and illustrated through a slope in Mexico. The formulation is based on the classical safety factor (SF) used in practice to appraise the slope stability, but it is introduced the treatment of uncertainties, and the slope failure probability is calculated as the probability that SF<1. As the main hazard is the rainfall on the area, statistics of rainfall intensity and duration are considered and modeled with an exponential distribution. The expected life-cycle cost is assessed by considering a monetary value on the slope failure consequences. Alternative mitigation measures are simulated, and the formulation is used to get the measures driving to the optimal one (minimum life-cycle costs). For the example, the optimal mitigation measure is the reduction on the slope inclination angle.

Keywords: expected life-cycle cost, failure probability, slopes failure, storms

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9605 Biophysical Analysis of the Interaction of Polymeric Nanoparticles with Biomimetic Models of the Lung Surfactant

Authors: Weiam Daear, Patrick Lai, Elmar Prenner

Abstract:

The human body offers many avenues that could be used for drug delivery. The pulmonary route, which is delivered through the lungs, presents many advantages that have sparked interested in the field. These advantages include; 1) direct access to the lungs and the large surface area it provides, and 2) close proximity to the blood circulation. The air-blood barrier of the alveoli is about 500 nm thick. The air-blood barrier consist of a monolayer of lipids and few proteins called the lung surfactant and cells. This monolayer consists of ~90% lipids and ~10% proteins that are produced by the alveolar epithelial cells. The two major lipid classes constitutes of various saturation and chain length of phosphatidylcholine (PC) and phosphatidylglycerol (PG) representing 80% of total lipid component. The major role of the lung surfactant monolayer is to reduce surface tension experienced during breathing cycles in order to prevent lung collapse. In terms of the pulmonary drug delivery route, drugs pass through various parts of the respiratory system before reaching the alveoli. It is at this location that the lung surfactant functions as the air-blood barrier for drugs. As the field of nanomedicine advances, the use of nanoparticles (NPs) as drug delivery vehicles is becoming very important. This is due to the advantages NPs provide with their large surface area and potential specific targeting. Therefore, studying the interaction of NPs with lung surfactant and whether they affect its stability becomes very essential. The aim of this research is to develop a biomimetic model of the human lung surfactant followed by a biophysical analysis of the interaction of polymeric NPs. This biomimetic model will function as a fast initial mode of testing for whether NPs affect the stability of the human lung surfactant. The model developed thus far is an 8-component lipid system that contains major PC and PG lipids. Recently, a custom made 16:0/16:1 PC and PG lipids were added to the model system. In the human lung surfactant, these lipids constitute 16% of the total lipid component. According to the author’s knowledge, there is not much monolayer data on the biophysical analysis of the 16:0/16:1 lipids, therefore more analysis will be discussed here. Biophysical techniques such as the Langmuir Trough is used for stability measurements which monitors changes to a monolayer's surface pressure upon NP interaction. Furthermore, Brewster Angle Microscopy (BAM) employed to visualize changes to the lateral domain organization. Results show preferential interactions of NPs with different lipid groups that is also dependent on the monolayer fluidity. Furthermore, results show that the film stability upon compression is unaffected, but there are significant changes in the lateral domain organization of the lung surfactant upon NP addition. This research is significant in the field of pulmonary drug delivery. It is shown that NPs within a certain size range are safe for the pulmonary route, but little is known about the mode of interaction of those polymeric NPs. Moreover, this work will provide additional information about the nanotoxicology of NPs tested.

Keywords: Brewster angle microscopy, lipids, lung surfactant, nanoparticles

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9604 Application of Bacteriophages as Natural Antibiotics in Aquaculture

Authors: Chamilani Nikapitiya, Mahanama De Zoysa, Jehee Lee

Abstract:

Most of the bacterial diseases are associated with high mortalities in aquaculture species and causing huge economic losses. Different approaches have been taken to prevent or control of bacterial diseases including use of vaccines, probiotics, chemotherapy, water quality management, etc. Antibiotics are widely applying as chemotherapy to control bacterial diseases, however, it has been shown that frequent use of antibiotics is favored to develop multi-drug resistance bacteria. Therefore, phages and phage encoded lytic proteins are known to be one of the most promising alternatives for antibiotics to avoid the emergence of antibiotic-resistant bacteria. We isolated and characterized the two lytic phages, namely pAh-1 and pAs-1 against pathogenic Aeromonas hydrophila and Aeromonas salmonicida, respectively. Morphological characteristics were analyzed by Transmission electron microscopy (TEM) and host strain specificities were tested with Aeromonas and other closely related bacterial strains. TEM analysis revealed that both pAh-1 and pAsm-1 are composed of an icosahedral head and a segmented tail, and we suggest that, they are new members of Myoviridae family. Genome sizes of isolated phages were estimated by restriction enzyme digestion of genomic DNA using selected endonucleases followed by agarose gel electrophoresis. Estimated genome size of pAh-1 and pAs-1 were approximately 64 Kbp and 120 Kbp, respectively. Both pAh-1 and pAs-1 have shown narrow host specificity. Moreover, protective effects of phage therapy against fish pathogenic A. hydrophila were investigated in zebrafish model. The survival rate was 40% higher when zebrafish received intra-peritoneal injection (i.p.) of pAh-1 were simultaneously challenge A. hydrophila (2 x 106 CFU/fish) compared to that without phage treatment. Overall results suggest that both pAh-1 and pAs-1 can be used as a potential phage therapy to control Aeromonas infections in aquaculture.

Keywords: Aeromonas infections, antibiotic resistance, bacteriophage, bio-control, lytic phage

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9603 In Vivo Antiulcer and Anti-Helicobacter pylori Activity of Geraniol on Acetic Acid plus Helicobacter pylori Induced Ulcer in Rats

Authors: Subrat Kumar Bhattamisra, Vivian Lee Yean Yan, Chin Koh Lee, Chew Hui Kuean, Yun Khoon Liew, Mayuren Candasamy

Abstract:

Geraniol, an acyclic monoterpenoid is the main active constituent in the essential oils of rose and palmorosa. Antioxidant, antibacterial, anticancer and antiulcer activity of geraniol was reported by many researchers. The present investigation was designed to study in vivo antiulcer and anti-Helicobacter pylori activity of geraniol. Antiulcer and anti-H. pylori activity of geraniol was evaluated on acetic acid plus H. pylori induced ulcer in rats. Acetic acid (0.03 mL) was injected to the sub-serosal layer of the stomach through laparotomy under anaesthesia. Orogastric inoculation of H. pylori (ATCC 43504) was done twice daily for 7 days. Geraniol (15 and 30 mg/kg), vehicle and standard drugs (Amoxicillin, 50 mg/kg; clarithromycin, 25 mg/kg & omeprazole, 20 mg/kg) was administered twice daily for 14 days. Antiulcer activity of geraniol was examined by the determination of gastric ulcer index, measuring the volume of gastric juice, pH and total acidity, myeloperoxidase activity and histopathological examination. Histopathological investigation for the presence of inflammation, white blood cell infiltration, edema, the mucosal damage was studied. The presence of H. pylori was detected by placing a biopsy sample from antral part of the stomach into rapid urease test. Ulcer index in H. pylori inoculated control group was 4.13 ± 0.85 and was significantly (P < 0.05) lowered in geraniol (30 mg/kg) and reference drug treated group. Geraniol increase the pH of the gastric juice (2.18 ± 0.13 in control vs. 4.14 ± 0.57 in geraniol 30mg/kg) and lower total acidity significantly (P < 0.01) in geraniol (15 & 30 mg/kg). Myeloperoxidase (MPO) activity was measured in stomach homogenate of all the groups. H. pylori control group has significant (P < 0.05) increase in MPO activity compared to normal control group. Geraniol (30 mg/kg) was showed significant (P < 0.05) and most effective among all the groups. Histopathological examination of rat stomach was scored and the total score for H. pylori control group was 8. After geraniol (30 mg/kg) and reference drug treatment, the histopathological score was significantly decreased and it was observed to be 3.5 and 2.0 respectively. Percentage inhibition of H. pylori infection in geraniol (30 mg/kg) and reference drug were found to be 40% and 50% respectively whereas, 100% infection in H. pylori control group was observed. Geraniol exhibited significant antiulcer and anti- H. pylori activity in the rats. Thus, geraniol has the potential for the further development as an effective medication in treating H. pylori associated ulcer.

Keywords: geraniol, helicobacter pylori atcc 43504, myeloperoxidase, ulcer

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9602 Hydroxyapatite Nanorods as Novel Fillers for Improving the Properties of PBSu

Authors: M. Nerantzaki, I. Koliakou, D. Bikiaris

Abstract:

This study evaluates the hypothesis that the incorporation of fibrous hydroxyapatite nanoparticles (nHA) with high crystallinity and high aspect ratio, synthesized by hydrothermal method, into Poly(butylene succinate) (PBSu), improves the bioactivity of the aliphatic polyester and affects new bone growth inhibiting resorption and enhancing bone formation. Hydroxyapatite nanorods were synthesized using a simple hydrothermal procedure. First, the HPO42- -containing solution was added drop-wise into the Ca2+-containing solution, while the molar ratio of Ca/P was adjusted at 1.67. The HA precursor was then treated hydrothermally at 200°C for 72 h. The resulting powder was characterized using XRD, FT-IR, TEM, and EDXA. Afterwards, PBSu nanocomposites containing 2.5wt% (nHA) were prepared by in situ polymerization technique for the first time and were examined as potential scaffolds for bone engineering applications. For comparison purposes composites containing either 2.5wt% micro-Bioglass (mBG) or 2.5wt% mBG-nHA were prepared and studied, too. The composite scaffolds were characterized using SEM, FTIR, and XRD. Mechanical testing (Instron 3344) and Contact Angle measurements were also carried out. Enzymatic degradation was studied in an aqueous solution containing a mixture of R. Oryzae and P. Cepacia lipases at 37°C and pH=7.2. In vitro biomineralization test was performed by immersing all samples in simulated body fluid (SBF) for 21 days. Biocompatibility was assessed using rat Adipose Stem Cells (rASCs), genetically modified by nucleofection with DNA encoding SB100x transposase and pT2-Venus-neo transposon expression plasmids in order to attain fluorescence images. Cell proliferation and viability of cells on the scaffolds were evaluated using fluoresce microscopy and MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide) assay. Finally, osteogenic differentiation was assessed by staining rASCs with alizarine red using cetylpyridinium chloride (CPC) method. TEM image of the fibrous HAp nanoparticles, synthesized in the present study clearly showed the fibrous morphology of the synthesized powder. The addition of nHA decreased significantly the contact angle of the samples, indicating that the materials become more hydrophilic and hence they absorb more water and subsequently degrade more rapidly. In vitro biomineralization test confirmed that all samples were bioactive as mineral deposits were detected by X-ray diffractometry after incubation in SBF. Metabolic activity of rASCs on all PBSu composites was high and increased from day 1 of culture to day 14. On day 28 metabolic activity of rASCs cultured on samples enriched with bioceramics was significantly decreased due to possible differentiation of rASCs to osteoblasts. Staining rASCs with alizarin red after 28 days in culture confirmed our initial hypothesis as the presence of calcium was detected, suggesting osteogenic differentiation of rACS on PBSu/nHAp/mBG 2.5% and PBSu/mBG 2.5% composite scaffolds.

Keywords: biomaterials, hydroxyapatite nanorods, poly(butylene succinate), scaffolds

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9601 Analytical Formulae for Parameters Involved in Side Slopes of Embankments Stability

Authors: Abdulrahman Abdulrahman, Abir Abdulrahman

Abstract:

The stability of slopes of earthen embankments is usually examined by Swedish slip circle method or the slices method. The factor of safety against sliding using Fellenius procedure depends upon the angle formed by the arc of sliding at the center ψ and the radius of the slip circle r. The values of both mentioned parameters ψ and r aren't precisely predicted because they are measured from the drawing. In this paper, analytical formulae were derived for finding the exact values of both ψ and r. Also this paper presents the different conditions of intersections the slip circle with the body of an earthen dam and the coordinate of intersection points. Numerical examples are chosen for demonstration the proposed solution

Keywords: earthen dams stability, , earthen embankments stability, , Fellenius method, hydraulic structures, , side slopes stability, , slices method, Swedish slip circle

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9600 Activity of Resveratrol on the Influence of Aflatoxin B1 on the Testes of Sprague Dawley Rats

Authors: Ali D. Omur, Betul Apaydin Yildirim, Yavuz S. Saglam, Selim Comakli, Mustafa Ozkaraca

Abstract:

Twenty-eight male Sprague Dawley rats (aged 3 months) were used in the study. The animals were given feed and water as ad libitum. Sprague Dawley rats were randomly divided into 4 groups as 7 rats in each group. Aflatoxin B1 (7.5 μg/200 g), resveratrol (60 mg/kg) was administered to rats in groups other than the control group. At the end of the 16th day, blood, semen and tissue specimens were taken by decapitation under ether anesthesia. The effects of aflatoxin B1 and resveratrol on spermatological, pathological and biochemical parameters were determined in rats. When we evaluate the spermatological parameters, it is understood that resveratrol has a statistically significant difference in terms of sperm motility and viability (membrane integrity) compared to the control group and aflatoxin B1 administration groups, indicating a protective effect on spermatological parameters (groups: control, resveratrol, aflatoxin B1 and Afb1 + res; respectively, values of motility: 71,42 ± 0,52b, 72,85 ± 1, 48c , 60,71 ± 1,30a, 57,14 ± 2, 40a; values of viability: 63,85 ± 1,33b, 70,42 ± 2,61c, 55,00 ± 1,54a, 56,57 ± 0,89a. In terms of pathological parameters -histopathological examination- in the control and resveratrol groups, seminiferous tubules were observed to be in normal structure. In the group treated with aflatoxin, the regular structure of the spermatogenic cells deteriorated, and the seminiferous tubules became necrotic and degenerative. In the group treated with Afb1 + res, the decreasing of necrotic and degenerative changes were determined compared with in the group treated with aflatoxin. As immunohistochemical examination, cleaved caspase 3 expression was found to be very low in the control and resveratrol groups. Cleaved caspase 3 expression was severely exacerbated in seminiferous tubules in aflatoxin group but cleaved caspase 3 expression level decreased in Afb1 + res. In the biochemical direction, resveratrol has been shown to inhibit the adverse effects of aflatoxin on antioxidant levels (GSH-mmol/L, CAT-kU/L, GPx-U/mL, SOD-EU/mL) and to show a protective effect. For this purpose, the use of resveratrol with antioxidant activity was investigated in preventing or ameliorating damage to aflatoxin B1. It has been concluded that resveratrol effectively prevents the aflatoxin-induced testicular damage and lipid peroxidation. It has also been shown that resveratrol has protective effects on sperm motility and viability.

Keywords: Aflatoxin B1, rat, resveratrol, sperm

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9599 The Effect of Ice in Pain Control before Digital Nerve Block

Authors: Fatemeh Rasooli, Behzad Simiari, Pooya Payandemehr, Amir Nejati, Maryam Bahreini, Atefeh Abdollahi

Abstract:

Introduction: Pain is a complex physiological reaction to tissue injury. In the course of painful procedures such as nerve block, ice has been shown to be a feasible and inexpensive material to control pain. It delays nerve conduction, actives other senses and reduces inflammatory and painful responses. This study assessed the effect of ice in reducing pain caused by needling and infiltration during digital block. Patient satisfaction recorded as a secondary outcome. Methods: This study was designed as a non-blinded randomized clinical trial approved by Tehran University of Medical Sciences Ethical Committee. Informed consent was taken from all the participants who were then randomly divided into two groups. Digital block performed by standard approach in selected patients. Tubes of ice were prepared in gloves and were fragmented at a time of application for circling around the finger. Tubes were applied for 6 minutes before digital nerve block in the site of needling in the case group. Patients in the control group underwent digital nerve block with the conventional method without ice administration. Numeric Rating Scale (NRS) used for grading pain. 0 used for no pain and 10 for the worst pain that patient had experienced until now. Scores were analyzed by Wilcoxon Rank Sum test and compared in case and control groups. Results: 100 patients aged 16-50 years were enrolled. Mean NRS scores with and without ice were 1.5 mm (S.D ± 1.44) and 6.8 mm (S.D ± 1.40) for needling pain and for infiltration pain were 2.7mm ( S.D ±1.65) and 8.5mm ( S.D ± 1.47), respectively (p<0.001). Besides, patients’ satisfactions were significantly higher in the ice group (p<0.001). Conclusion: Application of ice for 6 minutes significantly reduced pain of needling and infiltration in digital nerve block; thus, it seems to be a feasible and inexpensive material which acts effectively to decrease pain and stress before the procedure.

Keywords: digital block, ice, needle, pain

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9598 Soil Moisture Control System: A Product Development Approach

Authors: Swapneel U. Naphade, Dushyant A. Patil, Satyabodh M. Kulkarni

Abstract:

In this work, we propose the concept and geometrical design of a soil moisture control system (SMCS) module by following the product development approach to develop an inexpensive, easy to use and quick to install product targeted towards agriculture practitioners. The module delivers water to the agricultural land efficiently by sensing the soil moisture and activating the delivery valve. We start with identifying the general needs of the potential customer. Then, based on customer needs we establish product specifications and identify important measuring quantities to evaluate our product. Keeping in mind the specifications, we develop various conceptual solutions of the product and select the best solution through concept screening and selection matrices. Then, we develop the product architecture by integrating the systems into the final product. In the end, the geometric design is done using human factors engineering concepts like heuristic analysis, task analysis, and human error reduction analysis. The result of human factors analysis reveals the remedies which should be applied while designing the geometry and software components of the product. We find that to design the best grip in terms of comfort and applied force, for a power-type grip, a grip-diameter of 35 mm is the most ideal.

Keywords: agriculture, human factors, product design, soil moisture control

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9597 Simulation-Based Evaluation of Indoor Air Quality and Comfort Control in Non-Residential Buildings

Authors: Torsten Schwan, Rene Unger

Abstract:

Simulation of thermal and electrical building performance more and more becomes part of an integrative planning process. Increasing requirements on energy efficiency, the integration of volatile renewable energy, smart control and storage management often cause tremendous challenges for building engineers and architects. This mainly affects commercial or non-residential buildings. Their energy consumption characteristics significantly distinguish from residential ones. This work focuses on the many-objective optimization problem indoor air quality and comfort, especially in non-residential buildings. Based on a brief description of intermediate dependencies between different requirements on indoor air treatment it extends existing Modelica-based building physics models with additional system states to adequately represent indoor air conditions. Interfaces to corresponding HVAC (heating, ventilation, and air conditioning) system and control models enable closed-loop analyzes of occupants' requirements and energy efficiency as well as profitableness aspects. A complex application scenario of a nearly-zero-energy school building shows advantages of presented evaluation process for engineers and architects. This way, clear identification of air quality requirements in individual rooms together with realistic model-based description of occupants' behavior helps to optimize HVAC system already in early design stages. Building planning processes can be highly improved and accelerated by increasing integration of advanced simulation methods. Those methods mainly provide suitable answers on engineers' and architects' questions regarding more exuberant and complex variety of suitable energy supply solutions.

Keywords: indoor air quality, dynamic simulation, energy efficient control, non-residential buildings

Procedia PDF Downloads 219
9596 Trauma after Childbirth: The Mediating Effects of Subjective Experience

Authors: Grace Baptie, Jackie Andrade, Alison Bacon, Alyson Norman

Abstract:

Background: Many women experience their childbirth as traumatic, and 4-6% of mothers present with postnatal posttraumatic stress disorder (PTSD) as a result of their birth. Aims: To measure the relationship between obstetric and subjective experience of childbirth on mothers’ experience of postnatal trauma and identify salient aspects of the birth experience considered traumatic. Methods: Women who had given birth within the last year completed an online mixed-methods survey reporting on their subjective and obstetric birth experience as well as symptoms of postnatal trauma, depression and anxiety. Findings: 29% of mothers experienced their labour as traumatic and 15% met full or partial criteria for PTSD. Feeling supported and in control mediated the relationship between obstetric intervention and postnatal trauma symptoms. Five key themes were identified from the qualitative data regarding aspects of the birth considered traumatic including: obstetric complications; lack of control; concern for baby; psychological trauma and lack of support. Conclusion: Subjective birth experience is a significantly stronger predictor of postnatal trauma than level of medical intervention, the psychological consequences of which can be buffered by an increased level of support and control.

Keywords: birth trauma, perinatal mental health, postnatal PTSD, subjective experience

Procedia PDF Downloads 137
9595 Open Circuit MPPT Control Implemented for PV Water Pumping System

Authors: Rabiaa Gammoudi, Najet Rebei, Othman Hasnaoui

Abstract:

Photovoltaic systems use different techniques for tracking the Maximum Power Point (MPPT) to provide the highest possible power to the load regardless of the climatic conditions variation. In this paper, the proposed method is the Open Circuit (OC) method with sudden and random variations of insolation. The simulation results of the water pumping system controlled by OC method are validated by an experimental experience in real-time using a test bench composed by a centrifugal pump powered by a PVG via a boost chopper for the adaptation between the source and the load. The output of the DC/DC converter supplies the motor pump LOWARA type, assembly by means of a DC/AC inverter. The control part is provided by a computer incorporating a card DS1104 running environment Matlab/Simulink for visualization and data acquisition. These results show clearly the effectiveness of our control with a very good performance. The results obtained show the usefulness of the developed algorithm in solving the problem of degradation of PVG performance depending on the variation of climatic factors with a very good yield.

Keywords: PVWPS (PV Water Pumping System), maximum power point tracking (MPPT), open circuit method (OC), boost converter, DC/AC inverter

Procedia PDF Downloads 442
9594 Effectively Improving Cognition, Behavior, and Attitude of Diabetes Inpatients through Nutritional Education

Authors: Han Chih Feng, Yi-Cheng Hou, Jing-Huei Wu

Abstract:

Diabetes is a chronic disease. Nutrition knowledge and skills enable individuals with type 2 diabetes to optimize metabolic self-management and quality of life. This research studies the effect of nutritional education on diabetes inpatients in terms of their cognition, behavior, and attitude. The participants are inpatients diagnosed with diabetes at Taipei Tzu Chi Hospital. A total of 103 participants, 58 male, and 45 females, enrolled in the research between January 2018 and July 2018. The research evaluates cognition, behavior, and attitude level before and after nutritional education conducted by dietitians. The result shows significant improvement in actual consumption (2.5 ± 1.4 vs 3.8 ± 0.7; p<.001), diet control motivation (2.7 ± 0.8 vs 3.4 ± 0.6; p<.001), correct nutrition concept (1.2± 0.4 vs 2.4 ± 0.5; p<.001), learning willingness (2.7± 0.9 vs 3.4 ± 0.6; p<.001), cognitive behaviors (1.4 ± 0.5 vs 2.9 ± 0.7; p<.001). AC sugar (278.5 ± 321.5 vs 152.2 ± 49.1; p<.001) and HbA1C (10.3 ± 2.6 vs 8.6 ± 1.9; p<.001) are significant improvement after nutritional education. After nutritional education, participants oral hypoglycemic agents increased from 16 (9.2%) to 33 (19.0%), insulin decreased from 75 (43.1%) to 68 (39.1%), and hypoglycemic drugs combined with insulin decreased from 83 (47.7%) to 73 (42.0%).Further analysis shows that female inpatients have significant improvement in diet control motivation (3.91 ± 0.85 vs 4.44 ± 0.59; p<0.000), correct nutrition concept (3.24± 0.48 vs 4.47± 0.51; p<0.000), learning willingness (3.89 ± 0.86 vs 4.44 ± 0.59; p<0.000) and cognitive behaviors (2.42 ± 0.58 vs 4.02 ± 0.69; p<0.000); male inpatients have significant improvement in actual food intake (4.41± 0.92 vs 3.97 ± 0.42; p<0.000), diet control motivation (3.62 ± 0.86 vs 4.29 ± 0.62; p<0.000), correct nutrition concept (3.26 ± 0.44 vs 4.36 ± 0.49; p<0.000), learning willingness (3.72± 0.93 vs 4.33± 0.63; p<0.000) and cognitive behaviors (2.45± 0.54 vs 4.03± 0.77; p<0.000). In conclusion, nutritional education proves effective, regardless of gender, in improving an inpatient’s cognition, behavior, and attitude toward diabetes self-management.

Keywords: diabetes, nutrition education, actual consumption, diet control motivation, nutrition concept, learning willingness, cognitive behaviors

Procedia PDF Downloads 80
9593 Aerodynamic Coefficients Prediction from Minimum Computation Combinations Using OpenVSP Software

Authors: Marine Segui, Ruxandra Mihaela Botez

Abstract:

OpenVSP is an aerodynamic solver developed by National Aeronautics and Space Administration (NASA) that allows building a reliable model of an aircraft. This software performs an aerodynamic simulation according to the angle of attack of the aircraft makes between the incoming airstream, and its speed. A reliable aerodynamic model of the Cessna Citation X was designed but it required a lot of computation time. As a consequence, a prediction method was established that allowed predicting lift and drag coefficients for all Mach numbers and for all angles of attack, exclusively for stall conditions, from a computation of three angles of attack and only one Mach number. Aerodynamic coefficients given by the prediction method for a Cessna Citation X model were finally compared with aerodynamics coefficients obtained using a complete OpenVSP study.

Keywords: aerodynamic, coefficient, cruise, improving, longitudinal, openVSP, solver, time

Procedia PDF Downloads 223
9592 The Effects of Cow Manure Treated by Fruit Beetle Larvae, Waxworms and Tiger Worms on Plant Growth in Relation to Its Use as Potting Compost

Authors: Waleed S. Alwaneen

Abstract:

Dairy industry is flourishing in world to provide milk and milk products to local population. Besides milk products, dairy industries also generate a substantial amount of cow manure that significantly affects the environment. Moreover, heat produced during the decomposition of the cow manure adversely affects the crop germination. Different companies are producing vermicompost using different species of worms/larvae to overcome the harmful effects using fresh manure. Tiger worm treatment enhanced plant growth, especially in the compost-manure ratio (75% compost, 25% cow manure), followed by a ratio of 50% compost, 50% cow manure.  Results also indicated that plant growth in Waxworm treated manure was weak as compared to plant growth in compost treated with Fruit Beetle (FB), Waxworms (WW), and Control (C) especially in the compost (25% compost, 75% cow manure) and 100% cow manure where there was no growth at all. Freshplant weight, fresh leaf weight and fresh root weight were significantly higher in the compost treated with Tiger worms in (75% compost, 25% cow manure); no evidence was seen for any significant differences in the dry root weight measurement between FB, Tiger worms (TW), WW, Control (C) in all composts. TW produced the best product, especially at the compost ratio of 75% compost, 25% cow manure followed by 50% compost, 50% cow manure.

Keywords: fruit beetle, tiger worms, waxworms, control

Procedia PDF Downloads 125
9591 System-Driven Design Process for Integrated Multifunctional Movable Concepts

Authors: Oliver Bertram, Leonel Akoto Chama

Abstract:

In today's civil transport aircraft, the design of flight control systems is based on the experience gained from previous aircraft configurations with a clear distinction between primary and secondary flight control functions for controlling the aircraft altitude and trajectory. Significant system improvements are now seen particularly in multifunctional moveable concepts where the flight control functions are no longer considered separate but integral. This allows new functions to be implemented in order to improve the overall aircraft performance. However, the classical design process of flight controls is sequential and insufficiently interdisciplinary. In particular, the systems discipline is involved only rudimentarily in the early phase. In many cases, the task of systems design is limited to meeting the requirements of the upstream disciplines, which may lead to integration problems later. For this reason, approaching design with an incremental development is required to reduce the risk of a complete redesign. Although the potential and the path to multifunctional moveable concepts are shown, the complete re-engineering of aircraft concepts with less classic moveable concepts is associated with a considerable risk for the design due to the lack of design methods. This represents an obstacle to major leaps in technology. This gap in state of the art is even further increased if, in the future, unconventional aircraft configurations shall be considered, where no reference data or architectures are available. This means that the use of the above-mentioned experience-based approach used for conventional configurations is limited and not applicable to the next generation of aircraft. In particular, there is a need for methods and tools for a rapid trade-off between new multifunctional flight control systems architectures. To close this gap in the state of the art, an integrated system-driven design process for multifunctional flight control systems of non-classical aircraft configurations will be presented. The overall goal of the design process is to find optimal solutions for single or combined target criteria in a fast process from the very large solution space for the flight control system. In contrast to the state of the art, all disciplines are involved for a holistic design in an integrated rather than a sequential process. To emphasize the systems discipline, this paper focuses on the methodology for designing moveable actuation systems in the context of this integrated design process of multifunctional moveables. The methodology includes different approaches for creating system architectures, component design methods as well as the necessary process outputs to evaluate the systems. An application example of a reference configuration is used to demonstrate the process and validate the results. For this, new unconventional hydraulic and electrical flight control system architectures are calculated which result from the higher requirements for multifunctional moveable concept. In addition to typical key performance indicators such as mass and required power requirements, the results regarding the feasibility and wing integration aspects of the system components are examined and discussed here. This is intended to show how the systems design can influence and drive the wing and overall aircraft design.

Keywords: actuation systems, flight control surfaces, multi-functional movables, wing design process

Procedia PDF Downloads 131
9590 Two-Dimensional Dynamics Motion Simulations of F1 Rare Wing-Flap

Authors: Chaitanya H. Acharya, Pavan Kumar P., Gopalakrishna Narayana

Abstract:

In the realm of aerodynamics, numerous vehicles incorporate moving components to enhance their performance. For instance, airliners deploy hydraulically operated flaps and ailerons during take-off and landing, while Formula 1 racing cars utilize hydraulic tubes and actuators for various components, including the Drag Reduction System (DRS). The DRS, consisting of a rear wing and adjustable flaps, plays a crucial role in overtaking manoeuvres. The DRS has two positions: the default position with the flaps down, providing high downforce, and the lifted position, which reduces drag, allowing for increased speed and aiding in overtaking. Swift deployment of the DRS during races is essential for overtaking competitors. The fluid flow over the rear wing flap becomes intricate during deployment, involving flow reversal and operational changes, leading to unsteady flow physics that significantly influence aerodynamic characteristics. Understanding the drag and downforce during DRS deployment is crucial for determining race outcomes. While experiments can yield accurate aerodynamic data, they can be expensive and challenging to conduct across varying speeds. Computational Fluid Dynamics (CFD) emerges as a cost-effective solution to predict drag and downforce across a range of speeds, especially with the rapid deployment of the DRS. This study employs the finite volume-based solver Ansys Fluent, incorporating dynamic mesh motions and a turbulent model to capture the complex flow phenomena associated with the moving rear wing flap. A dedicated section for the rare wing-flap is considered in the present simulations, and the aerodynamics of these sections closely resemble S1223 aerofoils. Before delving into the simulations of the rare wing-flap aerofoil, numerical results undergo validation using experimental data from an NLR flap aerofoil case, encompassing different flap angles at two distinct angles of attack was carried out. The increase in flap angle as increase in lift and drag is observed for a given angle of attack. The simulation methodology for the rare-wing-flap aerofoil case involves specific time durations before lifting the flap. During this period, drag and downforce values are determined as 330 N and 1800N, respectively. Following the flap lift, a noteworthy reduction in drag to 55 % and a decrease in downforce to 17 % are observed. This understanding is critical for making instantaneous decisions regarding the deployment of the Drag Reduction System (DRS) at specific speeds, thereby influencing the overall performance of the Formula 1 racing car. Hence, this work emphasizes the utilization of dynamic mesh motion methodology to predict the aerodynamic characteristics during the deployment of the DRS in a Formula 1 racing car.

Keywords: DRS, CFD, drag, downforce, dynamics mesh motion

Procedia PDF Downloads 84
9589 Sliding Mode Control for Active Suspension System with Actuator Delay

Authors: Aziz Sezgin, Yuksel Hacioglu, Nurkan Yagiz

Abstract:

Sliding mode controller for a vehicle active suspension system is designed in this study. The widely used quarter car model is preferred and it is aimed to improve the ride comfort of the passengers. The effect of the actuator time delay, which may arise due to the information processing, sensors or actuator dynamics, is also taken into account during the design of the controller. A sliding mode controller was designed that has taken into account the actuator time delay by using Smith predictor. The successful performance of the designed controller is confirmed via numerical results.

Keywords: sliding mode control, active suspension system, actuator, time delay, vehicle

Procedia PDF Downloads 400
9588 On Fault Diagnosis of Asynchronous Sequential Machines with Parallel Composition

Authors: Jung-Min Yang

Abstract:

Fault diagnosis of composite asynchronous sequential machines with parallel composition is addressed in this paper. An adversarial input can infiltrate one of two submachines comprising the composite asynchronous machine, causing an unauthorized state transition. The objective is to characterize the condition under which the controller can diagnose any fault occurrence. Two control configurations, state feedback and output feedback, are considered in this paper. In the case of output feedback, the exact estimation of the state is impossible since the current state is inaccessible and the output feedback is given as the form of burst. A simple example is provided to demonstrate the proposed methodology.

Keywords: asynchronous sequential machines, parallel composition, fault diagnosis, corrective control

Procedia PDF Downloads 291