Search results for: frequency deviation control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 14971

Search results for: frequency deviation control

13201 The Role of Access Control Techniques in Creating a Safe Cyberspace for Children

Authors: Sara Muslat Alsahali, Nout Mohammed Alqahtani

Abstract:

Digital technology has changed the world, and with the increasing number of children accessing the Internet, it has now become an integral part of children's lives from their early years. With the rapid development of digital technology, the risks children face on the internet also evolve from cyberbullying to misuse, sexual exploitation, and abuse of their private information over the Internet. Digital technology, with its advantages and disadvantages, is now a fact of our life. Therefore, knowledge of how to reduce its risks and maximize its benefits will help shape the growth and future of a new generation of digital citizens. This paper will discuss access control techniques that help to create secure cyberspace where children can be safe without depriving them of their rights and freedom to use the internet and preventing them from its benefits. Also, it sheds light on its challenges and problems by classifying the methods of parental controlling into two possibilities asynchronous and synchronous techniques and choosing YouTube as a case study of access control techniques.

Keywords: access control, cyber security, kids, parental monitoring

Procedia PDF Downloads 137
13200 Morphological and Property Rights Control of Plot Pattern in Urban Regeneration: Case Inspiration from Germany and the United States

Authors: Nan Wu, Peng Liu

Abstract:

As a morphological element reflecting the land property rights structure, the plot pattern plays a crucial role in shaping the form and quality of the built environment. Therefore, it is one of the core control elements of urban regeneration. As China's urban development mode is shifting from growth-based development to urban regeneration, it is urgent to explore a more refined way for the planning control of the plot pattern, which further promotes the optimization of urban form and land property structure. European and American countries such as Germany and the United States began to deal with the planning control of plot patterns in urban regeneration earlier and established relatively mature methods and mechanisms. Therefore, this paper summarizes two typical scenarios of plot pattern regeneration in old cities in China: the first one is "limited scale plot pattern rezoning", which mainly deals with the regeneration scenario of tearing down the old and building the new, and the focus of its control is to establish an adaptive plot pattern rezoning methodology and mechanism; The second is "localized parcel regeneration under the existing property rights," which mainly deals with the renewal scenario of alteration and addition, and its control focuses on the establishment of control rules for individual plot regeneration. For the two typical plot pattern regeneration scenarios, Germany (Berlin) and the United States (New York) are selected as two international cases with reference significance, and the framework of plot pattern form and property rights control elements of urban regeneration is established from four latitudes, namely, the overall operation mode, form control methods, property rights control methods, and effective implementation prerequisites, so as to compare and analyze the plot pattern control methods of the two countries under different land systems and regeneration backgrounds. Among them, the German construction planning system has formed a more complete technical methodology for block-scale rezoning, and together with the overall urban design, it has created a practical example in the critical redevelopment of the inner city of Berlin. In the United States (New York), the zoning method establishes fine zoning regulations and rules for adjusting development rights based on the morphological indicators plots so as to realize effective control over the regeneration of local plots under the existing property rights pattern. On the basis of summarizing the international experience, we put forward the proposal of plot pattern and property rights control for the organic regeneration of old cities in China.

Keywords: plot pattern, urban regeneration, urban morphology, property rights, regulatory planning

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13199 The Structure and Development of a Wing Tip Vortex under the Effect of Synthetic Jet Actuation

Authors: Marouen Dghim, Mohsen Ferchichi

Abstract:

The effect of synthetic jet actuation on the roll-up and the development of a wing tip vortex downstream a square-tipped rectangular wing was investigated experimentally using hotwire anemometry. The wing is equipped with a hallow cavity designed to generate a high aspect ratio synthetic jets blowing at an angles with respect to the spanwise direction. The structure of the wing tip vortex under the effect of fluidic actuation was examined at a chord Reynolds number Re_c=8×10^4. An extensive qualitative study on the effect of actuation on the spanwise pressure distribution at c⁄4 was achieved using pressure scanner measurements in order to determine the optimal actuation parameters namely, the blowing momentum coefficient, Cμ, and the non-dimensionalized actuation frequency, F^+. A qualitative study on the effect of actuation parameters on the spanwise pressure distribution showed that optimal actuation frequencies of the synthetic jet were found within the range amplified by both long and short wave instabilities where spanwise pressure coefficients exhibited a considerable decrease by up to 60%. The vortex appeared larger and more diffuse than that of the natural vortex case. Operating the synthetic jet seemed to introduce unsteadiness and turbulence into the vortex core. Based on the ‘a priori’ optimal selected parameters, results of the hotwire wake survey indicated that the actuation achieved a reduction and broadening of the axial velocity deficit. A decrease in the peak tangential velocity associated with an increase in the vortex core radius was reported as a result of the accelerated radial transport of angular momentum. Peak vorticity level near the core was also found to be largely diffused as a direct result of the increased turbulent mixing within the vortex. The wing tip vortex a exhibited a reduced strength and a diffused core as a direct result of increased turbulent mixing due to the presence of turbulent small scale vortices within its core. It is believed that the increased turbulence within the vortex due to the synthetic jet control was the main mechanism associated with the decreased strength and increased size of the wing tip vortex as it evolves downstream. A comparison with a ‘non-optimal’ case was included to demonstrate the effectiveness of selecting the appropriate control parameters. The Synthetic Jet will be operated at various actuation configurations and an extensive parametric study is projected to determine the optimal actuation parameters.

Keywords: flow control, hotwire anemometry, synthetic jet, wing tip vortex

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13198 Effect of Packaging Material and Water-Based Solutions on Performance of Radio Frequency Identification for Food Packaging Applications

Authors: Amelia Frickey, Timothy (TJ) Sheridan, Angelica Rossi, Bahar Aliakbarian

Abstract:

The growth of large food supply chains demanded improved end-to-end traceability of food products, which has led to companies being increasingly interested in using smart technologies such as Radio Frequency Identification (RFID)-enabled packaging to track items. As technology is being widely used, there are several technological or economic issues that should be overcome to facilitate the adoption of this track-and-trace technology. One of the technological challenges of RFID technology is its sensitivity to different environmental form factors, including packaging materials and the content of the packaging. Although researchers have assessed the performance loss due to the proximity of water and aqueous solutions, there is still the need to further investigate the impacts of food products on the reading range of RFID tags. However, to the best of our knowledge, there are not enough studies to determine the correlation between RFID tag performance and food beverages properties. The goal of this project was to investigate the effect of the solution properties (pH and conductivity) and different packaging materials filled with food-like water-based solutions on the performance of an RFID tag. Three commercially available ultra high-frequency RFID tags were placed on three different bottles and filled with different concentrations of water-based solutions, including sodium chloride, citric acid, sucrose, and ethanol. Transparent glass, Polyethylneterephtalate (PET), and Tetrapak® were used as the packaging materials commonly used in the beverage industries. Tag readability (Theoretical Read Range, TRR) and sensitivity (Power on Tag Forward, PoF) were determined using an anechoic chamber. First, the best place to attach the tag for each packaging material was investigated using empty and water-filled bottles. Then, the bottles were filled with the food-like solutions and tested with the three different tags and the PoF and TRR at the fixed frequency of 915MHz. In parallel, the pH and conductivity of solutions were measured. The best-performing tag was then selected to test the bottles filled with wine, orange, and apple juice. Despite various solutions altering the performance of each tag, the change in tag performance had no correlation with the pH or conductivity of the solution. Additionally, packaging material played a significant role in tag performance. Each tag tested performed optimally under different conditions. This study is the first part of comprehensive research to determine the regression model for the prediction of tag performance behavior based on the packaging material and the content. More investigations, including more tags and food products, are needed to be able to develop a robust regression model. The results of this study can be used by RFID tag manufacturers to design suitable tags for specific products with similar properties.

Keywords: smart food packaging, supply chain management, food waste, radio frequency identification

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13197 Modeling and Power Control of DFIG Used in Wind Energy System

Authors: Nadia Ben Si Ali, Nadia Benalia, Nora Zerzouri

Abstract:

Wind energy generation has attracted great interests in recent years. Doubly Fed Induction Generator (DFIG) for wind turbines are largely deployed because variable-speed wind turbines have many advantages over fixed-speed generation such as increased energy capture, operation at maximum power point, improved efficiency, and power quality. This paper presents the operation and vector control of a Doubly-fed Induction Generator (DFIG) system where the stator is connected directly to a stiff grid and the rotor is connected to the grid through bidirectional back-to-back AC-DC-AC converter. The basic operational characteristics, mathematical model of the aerodynamic system and vector control technique which is used to obtain decoupled control of powers are investigated using the software Mathlab/Simulink.

Keywords: wind turbine, Doubly Fed Induction Generator, wind speed controller, power system stability

Procedia PDF Downloads 379
13196 Reduction of Rotor-Bearing-Support Finite Element Model through Substructuring

Authors: Abdur Rosyid, Mohamed El-Madany, Mohanad Alata

Abstract:

Due to simplicity and low cost, rotordynamic system is often modeled by using lumped parameters. Recently, finite elements have been used to model rotordynamic system as it offers higher accuracy. However, it involves high degrees of freedom. In some applications such as control design, this requires higher cost. For this reason, various model reduction methods have been proposed. This work demonstrates the quality of model reduction of rotor-bearing-support system through substructuring. The quality of the model reduction is evaluated by comparing some first natural frequencies, modal damping ratio, critical speeds and response of both the full system and the reduced system. The simulation shows that the substructuring is proven adequate to reduce finite element rotor model in the frequency range of interest as long as the numbers and the locations of master nodes are determined appropriately. However, the reduction is less accurate in an unstable or nearly-unstable system.

Keywords: rotordynamic, finite element model, timoshenko beam, 3D solid elements, Guyan reduction method

Procedia PDF Downloads 272
13195 Policy Guidelines to Enhance the Mathematics Teachers’ Association of the Philippines (MTAP) Saturday Class Program

Authors: Roselyn Alejandro-Ymana

Abstract:

The study was an attempt to assess the MTAP Saturday Class Program along its eight components namely, modules, instructional materials, scheduling, trainer-teachers, supervisory support, administrative support, financial support and educational facilities, the results of which served as bases in developing policy guidelines to enhance the MTAP Saturday Class Program. Using a descriptive development method of research, this study involved the participation of twenty-eight (28) schools with MTAP Saturday Class Program in the Division of Dasmarinas City where twenty-eight school heads, one hundred twenty-five (125) teacher-trainer, one hundred twenty-five (125) pupil program participants, and their corresponding one hundred twenty-five (125) parents were purposively drawn to constitute the study’s respondent. A self-made validated survey questionnaire together with Pre and Post-Test Assessment Test in Mathematics for pupils participating in the program, and an unstructured interview guide was used to gather the data needed in the study. Data obtained from the instruments administered was organized and analyzed through the use of statistical tools that included the Mean, Weighted Mean, Relative Frequency, Standard Deviation, F-Test or One-Way ANOVA and the T-Test. Results of the study revealed that all the eight domains involved in the MTAP Saturday Class Program were practiced with the areas of 'trainer-teachers', 'educational facilities', and 'supervisory support' identified as the program’s strongest components while the areas of 'financial support', 'modules' and 'scheduling' as being the weakest program’s components. Moreover, the study revealed based on F-Test, that there was a significant difference in the assessment made by the respondents in each of the eight (8) domains. It was found out that the parents deviated significantly from the assessment of either the school heads or the teachers on the indicators of the program. There is much to be desired when it comes to the quality of the implementation of the MTAP Saturday Class Program. With most of the indicators of each component of the program, having received overall average ratings that were at least 0.5 point away from the ideal rating 5 for total quality, school heads, teachers, and supervisors need to work harder for total quality of the implementation of the MTAP Saturday Class Program in the division.

Keywords: mathematics achievement, MTAP program, policy guidelines, program assessment

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13194 On-line Control of the Natural and Anthropogenic Safety in Krasnoyarsk Region

Authors: T. Penkova, A. Korobko, V. Nicheporchuk, L. Nozhenkova, A. Metus

Abstract:

This paper presents an approach of on-line control of the state of technosphere and environment objects based on the integration of Data Warehouse, OLAP and Expert systems technologies. It looks at the structure and content of data warehouse that provides consolidation and storage of monitoring data. There is a description of OLAP-models that provide a multidimensional analysis of monitoring data and dynamic analysis of principal parameters of controlled objects. The authors suggest some criteria of emergency risk assessment using expert knowledge about danger levels. It is demonstrated now some of the proposed solutions could be adopted in territorial decision making support systems. Operational control allows authorities to detect threat, prevent natural and anthropogenic emergencies and ensure a comprehensive safety of territory.

Keywords: decision making support systems, emergency risk assessment, natural and anthropogenic safety, on-line control, territory

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13193 Comparison of Comorbidity of Six Pathological Areas of MMPI and SCL-90-R Tests of Obsessive–Compulsive Patients

Authors: Fahimeh Rafiezadeh, Mehdi Khanbani

Abstract:

Aim:The goal of this research is to compare the comorbidity of mental disorders of obsessive–compulsive patients between multiplasic Minesota Personality Inventory (MMPI)and symptom checklist -90-R(SCL-90-R). Material and Method: In sorting, 50 individuals: 25 male and 25 female who were compulsive, were selected samples. The comparison was made in 6 pathological areas (somatoform, Depression, Anxiety, Paranoid, Phsychotism, and antisocial disorders). Frequencies were analyzed with chi-squre test. Results: results was concluded: In comparison between two sexes, there was a significant difference of frequency in depression disorder. Comparing the two tests, there was a significant difference of frequency between paranoid, depression and psychoticism disorders. Depression disorder had the highest comorbidity and antisocial disorder had the lowest comorbidity among male females and total. Conclusion: The depression has most comorbidity in OCD and is very important in the trapt of this patients.

Keywords: obsessive, compulsive disorder, comorbidity, MMPI test, SCL-90–R test

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13192 Optical Heterodyning of Injection-Locked Laser Sources: A Novel Technique for Millimeter-Wave Signal Generation

Authors: Subal Kar, Madhuja Ghosh, Soumik Das, Antara Saha

Abstract:

A novel technique has been developed to generate ultra-stable millimeter-wave signal by optical heterodyning of the output from two slave laser (SL) sources injection-locked to the sidebands of a frequency modulated (FM) master laser (ML). Precise thermal tuning of the SL sources is required to lock the particular slave laser frequency to the desired FM sidebands of the ML. The output signals from the injection-locked SL when coherently heterodyned in a fast response photo detector like high electron mobility transistor (HEMT), extremely stable millimeter-wave signal having very narrow line width can be generated. The scheme may also be used to generate ultra-stable sub-millimeter-wave/terahertz signal.

Keywords: FM sideband injection locking, master-slave injection locking, millimetre-wave signal generation, optical heterodyning

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13191 Test of Biological Control against Date Moth Ectomyelois ceratoniae zeller (Lepidoptera, Pyralidae) by Spinosad

Authors: Hadjeb Ayoub, Mehaoua Med Seghir, Ouakid M. Laid

Abstract:

Currently, chemical control is the only means used to control populations of the date moth (Ectomyelois ceratoniae) which is the most important and dangerous pest to palm groves in Algeria, conventional insecticides act faster, but their main drawback is it can’t be destroyed or degraded. In this context we conducted our work to explore the insecticidal activity of Spinpsad which is a bio-pesticide on the larval stages of Ectomyelois ceratoniae. The study of the effect of Spinosad on the mortality of different larval stages revealed that the doses used were significantly and positively correlated with mortality adjusted for different durations of exposure of larvae bio- pesticide. Lowest corrected mortality was observed in a short time and lethal in older larvae treated with the lowest concentration. While the higher mortality was observed in a longer duration of exposure in younger instars treated with the highest concentration.

Keywords: Ectomyelois ceratoniae, date palm, Spinosad, biological control, toxicology

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13190 Enhancement of Genetic Diversity through Cross Breeding of Two Catfish (Heteropneustes fossilis and Clarias batrachus) in Bangladesh

Authors: M. F. Miah, A. Chakrabarty

Abstract:

Two popular and highly valued fish, Stinging catfish (Heteropneustes fossilis) and Asian catfish (Clarias batrachus) are considered for observing genetic enhancement. Cross breeding was performed considering wild and farmed fish through inducing agent. Five RAPD markers were used to assess genetic diversity among parents and offspring of these two catfish for evaluating genetic enhancement in F1 generation. Considering different genetic data such as banding pattern of DNA, polymorphic loci, polymorphic information content (PIC), inter individual pair wise similarity, Nei genetic similarity, genetic distance, phylogenetic relationships, allele frequency, genotype frequency, intra locus gene diversity and average gene diversity of parents and offspring of these two fish were analyzed and finally in both cases higher genetic diversity was found in F1 generation than the parents.

Keywords: Heteropneustes fossilis, Clarias batrachus, cross breeding, genetic enhancement

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13189 Dielectric Properties of Ternary Composite Based on Complex Perovskite Oxides Synthesized by Semi-Wet Route

Authors: K. D. Mandal, Anil Kumar Mourya, Ankur Khare

Abstract:

Ceramics of 0.6 CaCu3TiO12 – 0.2 Bi2/3Cu3TiO12 – 0.2 Y2/3Cu3TiO12 (i.e. 0.6CCTO-0.2BCTO-0.2 YCTO) were prepared via semi - wet route. The phase structure of the sample was identified by X-Ray diffraction. The micro structure of the sample was observed by SEM, which displays grains of different shapes having diameter in range of 2 µm–4 µm. We have studied the frequency and temperature dependence of permittivity and impedance of the compound with LCR Meter in the range of 100 Hz–1 MHz and 300–500 K. The material shows its highest dielectric constant (428000) at 100 Hz and 368 K. The material shows Debye–like relaxation and their dielectric constant are independent of frequency and temperature over a wide range. The sample shows two electrical responses in impedance formalism, indicating that there are two distinct contributions. We attribute them to grain and grain boundaries in the ceramic sample and explain the dielectric behaviors by Maxwell–Wagner relaxation arising at the interfaces between grain and their boundaries.

Keywords: complex perovskite, ceramics composite, impedance study, SEM

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13188 Legal Allocation of Risks: A Computational Analysis of Force Majeure Clauses

Authors: Farshad Ghodoosi

Abstract:

This article analyzes the effect of supervening events in contracts. Contracts serve an important function: allocation of risks. In spite of its importance, the case law and the doctrine are messy and inconsistent. This article provides a fresh look at excuse doctrines (i.e., force majeure, impracticability, impossibility, and frustration) with a focus on force majeure clauses. The article makes the following contributions: First, it furnishes a new conceptual and theoretical framework of excuse doctrines. By distilling the decisions, it shows that excuse doctrines rests on the triangle of control, foreseeability, and contract language. Second, it analyzes force majeure clauses used by S&P 500 companies to understand the stickiness and similarity of such clauses and the events they cover. Third, using computational and statistical tools, it analyzes US cases since 1810 in order to assess the weight given to the triangle of control, foreseeability, and contract language. It shows that the control factor plays an important role in force majeure analysis, while the contractual interpretation is the least important factor. The Article concludes that it is the standard for control -whether the supervening event is beyond the control of the party- that determines the outcome of cases in the force majeure context and not necessarily the contractual language. This article has important implications on COVID-19-related contractual cases. Unlike the prevailing narrative that it is the language of the force majeure clause that’s determinative, this article shows that the primarily focus of the inquiry will be on whether the effects of COVID-19 have been beyond the control of the promisee. Normatively, the Article suggests that the trifactor of control, foreseeability, and contractual language are not effective for allocation of legal risks in times of crises. It puts forward a novel approach to force majeure clauses whereby that the courts should instead focus on the degree to which parties have relied on (expected) performance, in particular during the time of crisis.

Keywords: contractual risks, force majeure clauses, foreseeability, control, contractual language, computational analysis

Procedia PDF Downloads 149
13187 Reducing the Cooking Time of Bambara Groundnut (BGN)

Authors: Auswell Amfo-Antiri, Esther Eshun, Theresa A. Amu

Abstract:

Cooking Bambara groundnut (Bambara beans) is time and energy-consuming. Over time, some substances have been used to help reduce cooking time and save energy. This experimental study was carried out to find ways of reducing the cooking time of Bambara groundnut using selected organic substances. Twenty grams (20g) each of fresh pawpaw leaves, guava leaves, ginger, onion, and palm kernel were cooked with five samples of 200g of the creamy variety of raw Bambara groundnut. A control was cooked without any organic substance added. All six samples were cooked with equal quantities of water (4L); the gas mark used for cooking the samples was marked 5, the highest for the largest burner, using the same cooking pot. Gas matter. The control sample used 192 minutes to cook thoroughly. The ginger-treated sample (AET02) had the shortest cooking time of 145 minutes, followed by the onion-treated sample (AET05), with a cooking time of 157 minutes. The sample cooked with Palm kernel (AET06) and Pawpaw (AET04) used 172 minutes and 174 minutes, respectively, while sample AET03, cooked with Guava, used 185 minutes for cooking. The difference in cooking time for the sample treated with ginger (AET02) and onion (AET05) was 47 minutes and 35 minutes, respectively, as compared with the control. The comparison between Control and Pawpaw produced [p=0.163>0.05]; Control and Ginger yielded [p=0.006<0.05]; Control and Kernel resulted in [p=0.128>0.05]; Control and Guava resulted in [p=0.560>0.05]. The study concluded that ginger and onions comparatively reduced the cooking time for Bambara ground nut appreciably. The study recommended that ginger and onions could be used to reduce the cooking time of Bambara groundnut.

Keywords: cooking time, organic substances, ginger, onions, pawpaw leaves, guava leaves, bambara groundnut

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13186 Modified InVEST for Whatsapp Messages Forensic Triage and Search through Visualization

Authors: Agria Rhamdhan

Abstract:

WhatsApp as the most popular mobile messaging app has been used as evidence in many criminal cases. As the use of mobile messages generates large amounts of data, forensic investigation faces the challenge of large data problems. The hardest part of finding this important evidence is because current practice utilizes tools and technique that require manual analysis to check all messages. That way, analyze large sets of mobile messaging data will take a lot of time and effort. Our work offers methodologies based on forensic triage to reduce large data to manageable sets resulting easier to do detailed reviews, then show the results through interactive visualization to show important term, entities and relationship through intelligent ranking using Term Frequency-Inverse Document Frequency (TF-IDF) and Latent Dirichlet Allocation (LDA) Model. By implementing this methodology, investigators can improve investigation processing time and result's accuracy.

Keywords: forensics, triage, visualization, WhatsApp

Procedia PDF Downloads 168
13185 Effect of Fuel Lean Reburning Process on NOx Reduction and CO Emission

Authors: Changyeop Lee, Sewon Kim

Abstract:

Reburning is a useful technology in reducing nitric oxide through injection of a secondary hydrocarbon fuel. In this paper, an experimental study has been conducted to evaluate the effect of fuel lean reburning on NOx/CO reduction in LNG flame. Experiments were performed in flames stabilized by a co-flow swirl burner, which was mounted at the bottom of the furnace. Tests were conducted using LNG gas as the reburn fuel as well as the main fuel. The effects of reburn fuel fraction and injection manner of the reburn fuel were studied when the fuel lean reburning system was applied. The paper reports data on flue gas emissions and temperature distribution in the furnace for a wide range of experimental conditions. At steady state, temperature distribution and emission formation in the furnace have been measured and compared. This paper makes clear that in order to decrease both NOx and CO concentrations in the exhaust when the pulsated fuel lean reburning system was adapted, it is important that the control of some factors such as frequency and duty ratio. Also it shows the fuel lean reburning is also effective method to reduce NOx as much as reburning.

Keywords: fuel lean reburn, NOx, CO, LNG flame

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13184 Commutativity of Fractional Order Linear Time-Varying Systems

Authors: Salisu Ibrahim

Abstract:

The paper studies the commutativity associated with fractional order linear time-varying systems (LTVSs), which is an important area of study in control systems engineering. In this paper, we explore the properties of these systems and their ability to commute. We proposed the necessary and sufficient condition for commutativity for fractional order LTVSs. Through a simulation and mathematical analysis, we demonstrate that these systems exhibit commutativity under certain conditions. Our findings have implications for the design and control of fractional order systems in practical applications, science, and engineering. An example is given to show the effectiveness of the proposed method which is been computed by Mathematica and validated by the use of MATLAB (Simulink).

Keywords: fractional differential equation, physical systems, equivalent circuit, analog control

Procedia PDF Downloads 114
13183 Numerical Study on Self-Confined Plasmoid Transport Phenomena in an Electrodeless Plasma Thruster for Space Propulsion

Authors: Xiaodong Wen, Lijuan Liu, Xinfeng Sun

Abstract:

A high power electrodeless plasma thruster is being developed at Lanzhou Institute of Physics. In this thruster, a rotating magnetic field (RMF) driven by two radio-frequency coils which dephased by 90 degrees are applied both for propellant ionization and plasma acceleration. In the ionization stage, a very high azimuthal current can be driven by RMF and then makes plasma forms a field reversed configuration, namely self-confined plasmoid. Profoundly understanding the transport characteristics of the plasmoid in the following acceleration stage is the key to improve the thruster performances. In this paper, a 3D MHD model is established and the influences of the RMF and an applied magnetic field on the self-confined plasmoid acceleration are investigated. The simulation results show that, by applying a RMF with strength and frequency of 250 G and 370 kHz, the plasmoid can be accelerated to an average velocity of 17 km/s at the exit of the thruster.

Keywords: electric space propulsion, field reversed configuration, rotating magnetic field, transport phenomena

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13182 Application of Production Planning to Improve Operation in Local Factory

Authors: Bashayer Al-Enezi, Budoor Al-Sabti, Eman Al-Durai, Fatmah Kalban, Meshael Ahmed

Abstract:

Production planning and control principles are concerned with planning, controlling and balancing all aspects of manufacturing including raw materials, finished goods, production schedules, and equipment requirements. Hence, an effective production planning and control system is very critical to the success of any factory. This project will focus on the application of production planning and control principles on “The National Canned Food Production and Trading Company (NCFP)” factory to find problems or areas for improvement.

Keywords: production planning, operations improvement, inventory management, National Canned Food Production and Trading Company (NCFP)

Procedia PDF Downloads 506
13181 Infrared Lightbox and iPhone App for Improving Detection Limit of Phosphate Detecting Dip Strips

Authors: H. Heidari-Bafroui, B. Ribeiro, A. Charbaji, C. Anagnostopoulos, M. Faghri

Abstract:

In this paper, we report the development of a portable and inexpensive infrared lightbox for improving the detection limits of paper-based phosphate devices. Commercial paper-based devices utilize the molybdenum blue protocol to detect phosphate in the environment. Although these devices are easy to use and have a long shelf life, their main deficiency is their low sensitivity based on the qualitative results obtained via a color chart. To improve the results, we constructed a compact infrared lightbox that communicates wirelessly with a smartphone. The system measures the absorbance of radiation for the molybdenum blue reaction in the infrared region of the spectrum. It consists of a lightbox illuminated by four infrared light-emitting diodes, an infrared digital camera, a Raspberry Pi microcontroller, a mini-router, and an iPhone to control the microcontroller. An iPhone application was also developed to analyze images captured by the infrared camera in order to quantify phosphate concentrations. Additionally, the app connects to an online data center to present a highly scalable worldwide system for tracking and analyzing field measurements. In this study, the detection limits for two popular commercial devices were improved by a factor of 4 for the Quantofix devices (from 1.3 ppm using visible light to 300 ppb using infrared illumination) and a factor of 6 for the Indigo units (from 9.2 ppm to 1.4 ppm) with repeatability of less than or equal to 1.2% relative standard deviation (RSD). The system also provides more granular concentration information compared to the discrete color chart used by commercial devices and it can be easily adapted for use in other applications.

Keywords: infrared lightbox, paper-based device, phosphate detection, smartphone colorimetric analyzer

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13180 Smart Surveillance with 5G: A Performance Study in Adama City

Authors: Shenko Chura Aredo, Hailu Belay, Kevin T. Kornegay

Abstract:

In light of Adama City’s smart city development vision, this study thoroughly investigates the performance of smart security systems with Fifth Generation (5G) network capabilities. It can be logistically difficult to install a lot of cabling, particularly in big or dynamic settings. Moreover, latency issues might affect linked systems, making it difficult for them to monitor in real time. Through a focused analysis that employs Adama City as a case study, the performance has been evaluated in terms of spectrum and energy efficiency using empirical data and basic signal processing formulations at different frequency resources. The findings also demonstrate that cameras working at higher 5G frequencies have more capacity than those operating at sub-6 GHz, notwithstanding frequency-related issues. It has also been noted that when the beams of such cameras are adaptively focussed based on the distance of the last cell edge user rather than the maximum cell radius, less energy is required than with conventional fixed power ramping.

Keywords: 5G, energy efficiency, safety, smart security, spectral efficiency

Procedia PDF Downloads 19
13179 Commutativity of Fractional Order Linear Time-Varying System

Authors: Salisu Ibrahim

Abstract:

The paper studies the commutativity associated with fractional order linear time-varying systems (LTVSs), which is an important area of study in control systems engineering. In this paper, we explore the properties of these systems and their ability to commute. We proposed the necessary and sufficient condition for commutativity for fractional order LTVSs. Through a simulation and mathematical analysis, we demonstrate that these systems exhibit commutativity under certain conditions. Our findings have implications for the design and control of fractional order systems in practical applications, science, and engineering. An example is given to show the effectiveness of the proposed method which is been computed by Mathematica and validated by the use of Matlab (Simulink).

Keywords: fractional differential equation, physical systems, equivalent circuit, and analog control

Procedia PDF Downloads 77
13178 Development of Configuration Software of Space Environment Simulator Control System Based on Linux

Authors: Zhan Haiyang, Zhang Lei, Ning Juan

Abstract:

This paper presents a configuration software solution in Linux, which is used for the control of space environment simulator. After introducing the structure and basic principle, it is said that the developing of QT software frame and the dynamic data exchanging between PLC and computer. The OPC driver in Linux is also developed. This driver realizes many-to-many communication between hardware devices and SCADA software. Moreover, an algorithm named “Scan PRI” is put forward. This algorithm is much more optimizable and efficient compared with "Scan in sequence" in Windows. This software has been used in practical project. It has a good control effect and can achieve the expected goal.

Keywords: Linux OS, configuration software, OPC Server driver, MYSQL database

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13177 Robust Control of a Dynamic Model of an F-16 Aircraft with Improved Damping through Linear Matrix Inequalities

Authors: J. P. P. Andrade, V. A. F. Campos

Abstract:

This work presents an application of Linear Matrix Inequalities (LMI) for the robust control of an F-16 aircraft through an algorithm ensuring the damping factor to the closed loop system. The results show that the zero and gain settings are sufficient to ensure robust performance and stability with respect to various operating points. The technique used is the pole placement, which aims to put the system in closed loop poles in a specific region of the complex plane. Test results using a dynamic model of the F-16 aircraft are presented and discussed.

Keywords: F-16 aircraft, linear matrix inequalities, pole placement, robust control

Procedia PDF Downloads 306
13176 Creeping Control Strategy for Direct Shift Gearbox Based on the Investigation of Temperature Variation of the Wet Clutch

Authors: Biao Ma, Jikai Liu, Man Chen, Jianpeng Wu, Liyong Wang, Changsong Zheng

Abstract:

Proposing an appropriate control strategy is an effective and practical way to address the overheat problems of the wet multi-plate clutch in Direct Shift Gearbox under the long-time creeping condition. To do so, the temperature variation of the wet multi-plate clutch is investigated firstly by establishing a thermal resistance model for the gearbox cooling system. To calculate the generated heat flux and predict the clutch temperature precisely, the friction torque model is optimized by introducing an improved friction coefficient, which is related to the pressure, the relative speed and the temperature. After that, the heat transfer model and the reasonable friction torque model are employed by the vehicle powertrain model to construct a comprehensive co-simulation model for the Direct Shift Gearbox (DSG) vehicle. A creeping control strategy is then proposed and, to evaluate the vehicle performance, the safety temperature (250 ℃) is particularly adopted as an important metric. During the creeping process, the temperature of two clutches is always under the safety value (250 ℃), which demonstrates the effectiveness of the proposed control strategy in avoiding the thermal failures of clutches.

Keywords: creeping control strategy, direct shift gearbox, temperature variation, wet clutch

Procedia PDF Downloads 133
13175 A Unique Exact Approach to Handle a Time-Delayed State-Space System: The Extraction of Juice Process

Authors: Mohamed T. Faheem Saidahmed, Ahmed M. Attiya Ibrahim, Basma GH. Elkilany

Abstract:

This paper discusses the application of Time Delay Control (TDC) compensation technique in the juice extraction process in a sugar mill. The objective is to improve the control performance of the process and increase extraction efficiency. The paper presents the mathematical model of the juice extraction process and the design of the TDC compensation controller. Simulation results show that the TDC compensation technique can effectively suppress the time delay effect in the process and improve control performance. The extraction efficiency is also significantly increased with the application of the TDC compensation technique. The proposed approach provides a practical solution for improving the juice extraction process in sugar mills using MATLAB Processes.

Keywords: time delay control (TDC), exact and unique state space model, delay compensation, Smith predictor.

Procedia PDF Downloads 92
13174 Adaptive Optimal Controller for Uncertain Inverted Pendulum System: A Dynamic Programming Approach for Continuous Time System

Authors: Dao Phuong Nam, Tran Van Tuyen, Do Trong Tan, Bui Minh Dinh, Nguyen Van Huong

Abstract:

In this paper, we investigate the adaptive optimal control law for continuous-time systems with input disturbances and unknown parameters. This paper extends previous works to obtain the robust control law of uncertain systems. Through theoretical analysis, an adaptive dynamic programming (ADP) based optimal control is proposed to stabilize the closed-loop system and ensure the convergence properties of proposed iterative algorithm. Moreover, the global asymptotic stability (GAS) for closed system is also analyzed. The theoretical analysis for continuous-time systems and simulation results demonstrate the performance of the proposed algorithm for an inverted pendulum system.

Keywords: approximate/adaptive dynamic programming, ADP, adaptive optimal control law, input state stability, ISS, inverted pendulum

Procedia PDF Downloads 194
13173 A Survey on Frequency of Cryptosporidiosis and Giardiasis in Horses in Ahvaz South-West of Iran

Authors: Ali R. Ghadrdan-Mashhadi, Hosein Hamidi-Nejat, Parisa Alizadehnia

Abstract:

Cryptosporidia and Giardia are protozoan parasites that have worldwide distribution and infect a variety of animals. Although, the infection to these parasites rarely caused to illness in horses, but some veterinarian recorded the clinical signs (such as diarrhea and malabsorbtion) especially in foals. In present study, the frequency of Cryptosporidiosis and Giardiasis in horses in Ahvaz investigated. The feces samples were taken from 100 horses that keep in seven horse breeding clubs, during spring and summer. The ages of horses were from 1 month to 27 years old. Fecal samples were stained by modified Ziehl-Neelsen and Tri-chrome methods. Results were analyzed with Chi-square Test and Fisher’s exact test. The results showed that the rate of infection to Cryptosporidium and Giardia were 18% and 40%, respectively. There weren't significant differences between infection to Cryptosporidium and Giardia with sex, age and fecal constancy. Although, the rate of infection to Cryptosporidium in studied horses is very similar to other studies but it seems, the rate of infection to Giardia is high in compare to other studies were done in the other countries.

Keywords: Ahvaz, cryptosporidium, giardia, horse

Procedia PDF Downloads 363
13172 Effect of Different Chemical Concentrations on Control of Dodder (Cuscuta campestris Yunck.) in Vitex (Agnus castus)

Authors: Aliyu B. Mustapha, Poul A. Gida

Abstract:

Pot experiment was conducted at the landscape unit of Modibbo Adama University of Technology, Yola in 2015 and 2016 to determine the effect of some chemicals namely glyphosate, salt and detergent on Golden dodder (Cuscuta campestris Yunk). The experiment was laid in a completely randomized design (CRD) with three replications. The treatments include the following: glyphosate-T0= (control),(Og a.i/ha-1) T1=35g a.i/ha-1, T2=70g a.i/ha-1, T3=105g a.i/ha-1, T4=140 a.i/ha-1 and T5=175g a.i/ha-1: Salt (T0=control O mole/ha-1 T1=1mole/ha-1 T2=2mole/ha-1, T3=3mole/ha-1 , T4=4mole/ha-1 and T5=5mole/ha-1:washing detergent T0=Og/ha-1(control), T1=30ml detergent +70ml distilled water T2=45ml detergent+65ml distilled water T3=60ml detergent+40ml distilled water, T4=75ml detergent+25ml distilled water and T5=90ml detergent +10mldistilled water, the treatments were replicated three times. Data were collected include: plant height, number of leaves, leaf area, leaf area index and Cuscuta cover score at 3,6,9and 12 weeks after sprouting(WAS). Biomas of Vitex was also collected at the end of the experiment. Data collected were analyzed using software Genstat version 8.0. Results showed that glyphosate gave the least Cuscuta cover score and the tallest Vitex plant. However, detergent mildly controlled Cuscuta, while salt has no effect on Cuscuta campestris indicating that glyphosate could be used in the control of parasitic dodder (Cuscuta campestris) on Vitex plant.

Keywords: chemical, control, dudder, Vitex

Procedia PDF Downloads 189