Search results for: air pollution control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 12130

Search results for: air pollution control

10960 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

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10959 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

Procedia PDF Downloads 397
10958 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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10957 Indoor Air Pollution of the Flexographic Printing Environment

Authors: Jelena S. Kiurski, Vesna S. Kecić, Snežana M. Aksentijević

Abstract:

The identification and evaluation of organic and inorganic pollutants were performed in a flexographic facility in Novi Sad, Serbia. Air samples were collected and analyzed in situ, during 4-hours working time at five sampling points by the mobile gas chromatograph and ozonometer at the printing of collagen casing. Experimental results showed that the concentrations of isopropyl alcohol, acetone, total volatile organic compounds and ozone varied during the sampling times. The highest average concentrations of 94.80 ppm and 102.57 ppm were achieved at 200 minutes from starting the production for isopropyl alcohol and total volatile organic compounds, respectively. The mutual dependences between target hazardous and microclimate parameters were confirmed using a multiple linear regression model with software package STATISTICA 10. Obtained multiple coefficients of determination in the case of ozone and acetone (0.507 and 0.589) with microclimate parameters indicated a moderate correlation between the observed variables. However, a strong positive correlation was obtained for isopropyl alcohol and total volatile organic compounds (0.760 and 0.852) with microclimate parameters. Higher values of parameter F than Fcritical for all examined dependences indicated the existence of statistically significant difference between the concentration levels of target pollutants and microclimates parameters. Given that, the microclimate parameters significantly affect the emission of investigated gases and the application of eco-friendly materials in production process present a necessity.

Keywords: flexographic printing, indoor air, multiple regression analysis, pollution emission

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10956 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

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10955 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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10954 A Close Study on the Nitrate Fertilizer Use and Environmental Pollution for Human Health in Iran

Authors: Saeed Rezaeian, M. Rezaee Boroon

Abstract:

Nitrogen accumulates in soils during the process of fertilizer addition to promote the plant growth. When the organic matter decomposes, the form of available nitrogen produced is in the form of nitrate, which is highly mobile. The most significant health effect of nitrate ingestion is methemoglobinemia in infants under six months of age (blue baby syndrome). The mobile nutrients, like nitrate nitrogen, are not stored in the soil as the available forms for the long periods and in large amounts. It depends on the needs for the crops such as vegetables. On the other hand, the vegetables will compete actively for nitrate nitrogen as a mobile nutrient and water. The mobile nutrients must be shared. The fewer the plants, the larger this share is for each plant. Also, this nitrate nitrogen is poisonous for the people who use these vegetables. Nitrate is converted to nitrite by the existing bacteria in the stomach and the Gastro-Intestinal (GI) tract. When nitrite is entered into the blood cells, it converts the hemoglobin to methemoglobin, which causes the anoxemia and cyanosis. The increasing use of pesticides and chemical fertilizers, especially the fertilizers with nitrates compounds, which have been common for the increased production of agricultural crops, has caused the nitrate pollution in the (soil, water, and environment). They have caused a lot of damage to humans and animals. In this research, the nitrate accumulation in different kind of vegetables such as; green pepper, tomatoes, egg plants, watermelon, cucumber, and red pepper were observed in the suburbs of Mashhad, Neisabour, and Sabzevar cities. In some of these cities, the information forms of agronomical practices collected were such as; different vegetable crops fertilizer recommendations, varieties, pesticides, irrigation schedules, etc., which were filled out by some of our colleagues in the research areas mentioned above. Analysis of the samples was sent to the soil and water laboratory in our department in Mashhad. The final results from the chemical analysis of samples showed that the mean levels of nitrates from the samples of the fruit crops in the mentioned cities above were all lower than the critical levels. These fruit crop samples were in the order of: 35.91, 8.47, 24.81, 6.03, 46.43, 2.06 mg/kg dry matter, for the following crops such as; tomato, cucumber, eggplant, watermelon, green pepper, and red pepper. Even though, this study was conducted with limited samples and by considering the mean levels, the use of these crops from the nutritional point of view will not cause the poisoning of humans.

Keywords: environmental pollution, human health, nitrate accumulations, nitrate fertilizers

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10953 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 106
10952 Urban Boundary Layer and Its Effects on Haze Episode in Thailand

Authors: S. Bualert, K. Duangmal

Abstract:

Atmospheric boundary layer shows effects of land cover on atmospheric characteristic in term of temperature gradient and wind profile. They are key factors to control atmospheric process such as atmospheric dilution and mixing via thermal and mechanical turbulent. Bangkok, ChiangMai, and Hatyai are major cities of central, southern and northern of Thailand, respectively. The different of them are location, geography and size of the city, Bangkok is the most urbanized city and classified as mega city compared to ChiangMai and HatYai, respectively. They have been suffering from air pollution episode such as transboundary haze. The worst period of the northern part of Thailand was occurred at the end of February through April of each year. The particulate matter less than 10 micrometer (PM10) concentrations were higher than Thai’s ambient air quality standard (120 micrograms per cubic meter) more than two times. Radiosonde technique and air pollutant (CO, PM10, TSP, O3, NOx) measurements were used to identify characteristics of urban boundary layer and air pollutions problems in the cities. Furthermore, air pollutant profiles showed good relationship to characteristic’s urban boundary layer especially on daytime temperature inversion on 29 February 2009 caused two times higher than normal concentrations of CO and particulate matter.

Keywords: haze episode, micrometeorology, temperature inversion, urban boundary layer

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10951 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 494
10950 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 70
10949 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

Procedia PDF Downloads 281
10948 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

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10947 Do the Health Benefits of Oil-Led Economic Development Outweigh the Potential Health Harms from Environmental Pollution in Nigeria?

Authors: Marian Emmanuel Okon

Abstract:

Introduction: The Niger Delta region of Nigeria has a vast reserve of oil and gas, which has globally positioned the nation as the sixth largest exporter of crude oil. Production rapidly rose following oil discovery. In most oil producing nations of the world, the wealth generated from oil production and export has propelled economic advancement, enabling the development of industries and other relevant infrastructures. Therefore, it can be assumed that majority of the oil resource such as Nigeria’s, has the potential to improve the health of the population via job creation and derived revenues. However, the health benefits of this economic development might be offset by the environmental consequences of oil exploitation and production. Objective: This research aims to evaluate the balance between the health benefits of oil-led economic development and harmful environmental consequences of crude oil exploitation in Nigeria. Study Design: A pathway has been designed to guide data search and this study. The model created will assess the relationship between oil-led economic development and population health development via job creation, improvement of education, development of infrastructure and other forms of development as well as through harmful environmental consequences from oil activities. Data/Emerging Findings: Diverse potentially suitable datasets which are at different geographical scales have been identified, obtained or applied for and the dataset from the World Bank has been the most thoroughly explored. This large dataset contains information that would enable the longitudinal assessment of both the health benefits and harms from oil exploitation in Nigeria as well as identify the disparities that exist between the communities, states and regions. However, these data do not extend far back enough in time to capture the start of crude oil production. Thus, it is possible that the maximum economic benefits and health harms could be missed. To deal with this shortcoming, the potential for a comparative study with countries like United Kingdom, Morocco and Cote D’ivoire has also been taken into consideration, so as to evaluate the differences between these countries as well as identify the areas of improvement in Nigeria’s environmental and health policies. Notwithstanding, these data have shown some differences in each country’s economic, environmental and health state over time as well as a corresponding summary statistics. Conclusion: In theory, the beneficial effects of oil exploitation to the health of the population may be substantial as large swaths of the ‘wider determinants’ of population heath are influenced by the wealth of a nation. However, if uncontrolled, the consequences from environmental pollution and degradation may outweigh these benefits. Thus, there is a need to address this, in order to improve environmental and population health in Nigeria.

Keywords: environmental pollution, health benefits, oil-led economic development, petroleum exploitation

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10946 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

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10945 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.

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10944 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

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10943 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

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10942 Algorithms of ABS-Plastic Extrusion

Authors: Dmitrii Starikov, Evgeny Rybakov, Denis Zhuravlev

Abstract:

Plastic for 3D printing is very necessary material part for printers. But plastic production is technological process, which implies application of different control algorithms. Possible algorithms of providing set diameter of plastic fiber are proposed and described in the article. Results of research were proved by existing unit of filament production.

Keywords: ABS-plastic, automation, control system, extruder, filament, PID-algorithm

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10941 The Effect of Incorporation of Inulin as a Fat Replacer on the Quality of Milk Products Vis-À-Vis Ice Cream

Authors: Harish Kumar Sharma

Abstract:

The influence of different levels of inulin as a fat replacer on the quality of ice cream was investigated. The physicochemical, rheological and textural properties of control ice cream and ice cream prepared with inulin in different proportions were determined and correlated to the different parameters using Pearson correlation and Principle Component Analysis (PCA). Based on the overall acepectability, ice cream with 4% inulin was found best and was selected for preparation of ice cream with inulin:SPI in different proportions. Compared with control ice cream, Inulin:SPI showed different rheological properties, resulting in significantly higher apparent viscosities, consistency coefficient and greater deviations from Newtonian flow. In addition, both hardness and melting resistance significantly increased with increase in the SPI content in ice cream prepared with inulin: SPI. Also hardness value increased for inulin based ice cream compared to control ice cream but it melted significantly faster than the latter. Colour value significantly decreased in both the cases compared to the control sample. The deliberation shall focus on the effect of incorporation of inulin on the quality of ice-cream.

Keywords: fat replacer, inulin, ice cream, viscosity, principal component analysis

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10940 Frequency Control of Self-Excited Induction Generator Based Microgrid during Transition from Grid Connected to Island Mode

Authors: Azhar Ulhaq, Zubair Yameen, Almas Anjum

Abstract:

Frequency behaviour of self-excited induction generator (SEIG) wind turbines during control mode transition from grid connected to islanded mode is studied in detail. A robust control scheme for frequency regulation based on combined action of STATCOM, energy storage system (ESS) and pitch angle control for wind powered microgrid (MG) is proposed. Suggested STATCOM controller comprises a 3-phase voltage source converter (VSC) that contains insulated gate bipolar transistors (IGBTs) based pulse width modulation (PWM) inverters along with a capacitor bank. Energy storage system control consists of current controlled voltage source converter and battery bank. Both of them acting simultaneously after detection of island compensates for reactive and active power demands, thus regulating frequency at point of common coupling (PCC) and also improves load stability. STATCOM integrates at point of common coupling and ESS is connected to microgrids main bus. Results reveal that proposed control not only stabilizes frequency during transition duration but also minimizes sudden frequency imbalance caused by load variation or wind intermittencies in islanded operation. System is investigated with and without suggested control scheme. The efficacy of proposed strategy has been verified by simulation in MATLAB/Simulink.

Keywords: energy storage system, island, wind, STATCOM, self-excited induction generator, SEIG, transient

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10939 Neural Adaptive Controller for a Class of Nonlinear Pendulum Dynamical System

Authors: Mohammad Reza Rahimi Khoygani, Reza Ghasemi

Abstract:

In this paper, designing direct adaptive neural controller is applied for a class of a nonlinear pendulum dynamic system. The radial basis function (RBF) is used for the Neural network (NN). The adaptive neural controller is robust in presence of external and internal uncertainties. Both the effectiveness of the controller and robustness against disturbances are the merits of this paper. The promising performance of the proposed controllers investigates in simulation results.

Keywords: adaptive control, pendulum dynamical system, nonlinear control, adaptive neural controller, nonlinear dynamical, neural network, RBF, driven pendulum, position control

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10938 Flood Control Structures in the River Göta Älv to Protect Gothenburg City (Sweden) during the 21st Century: Preliminary Evaluation

Authors: M. Irannezhad, E. H. N. Gashti, U. Moback, B. Kløve

Abstract:

Climate change because of increases in concentration level of greenhouse gases emissions to the atmosphere will result in mean sea level rise about +1 m by 2100. To prevent coastal floods resulted from the sea level rising, different flood control structures have been built, e.g. the Thames barrier on the Thames River in London (UK), with acceptable protection levels at least so far. Gothenburg located on the southwest coast of Sweden, with the River Göta älv running through it, is one of vulnerable cities to the accelerated rises in mean sea level. Developing a water level model by MATLAB, we evaluated using a sea barrage in the Göta älv River as the flood control structure for protecting the Gothenburg city during this century. Considering three operational scenarios for two barriers in upstream and downstream, the highest sea level was estimated to + 2.95 m above the current mean sea level by 2100. To verify flood protection against such high sea levels, both barriers have to be closed. To prevent high water level in the River Göta älv reservoir, the barriers would be open when the sea level is low. The suggested flood control structures would successfully protect the city from flooding events during this century.

Keywords: climate change, flood control structures, gothenburg, sea level rising, water level mode

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10937 Control of Oxide and Silicon Loss during Exposure of Silicon Waveguide

Authors: Gu Zhonghua

Abstract:

Control method of bulk silicon dioxide etching process to approach then expose silicon waveguide has been developed. It has been demonstrated by silicon waveguide of photonics devices. It is also able to generalize other applications. Use plasma dry etching to etch bulk silicon dioxide and approach oxide-silicon interface accurately, then use dilute HF wet etching to etch silicon dioxide residue layer to expose the silicon waveguide as soft landing. Plasma dry etch macro loading effect and endpoint technology was used to determine dry etch time accurately with a low wafer expose ratio.

Keywords: waveguide, etch, control, silicon loss

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10936 The Effect of Low and High Dose Curcumin Supplementation on Prevention and Treatment of Sarcopenia: The Concept of Hormesis

Authors: Sevana Daneghian, Leila Chodari, Sahar Mehranfar, Shadi Mohammadpour-Asl, Diman Mahdi

Abstract:

Sarcopenia is an age-related muscle disease. Lack of antioxidant protection, and cumulative oxidative damage to skeletal muscle are recognized mechanisms. Curcumin is a hormetin as it has a stimulating effect in low doses and an inhibitory effect in high doses. The purpose of this study was to examine the effects of four weeks of curcumin supplementation in presarcopenic and sarcopenic rats, and likelihood of potential negative effects while co-exist with sarcopenia. The rats were divided into 7 groups: young sham rats, 18 months old; presarcopenic control, supplemented with 400 and 1500 mg/kg/day, 24 months old; Sarcopenia control, sarcopenia supplemented with 400 and 1500 mg/kg/day. MDA levels were significantly reduced in the low-dose pre-sarcopenic group compared to the control group. Compared to the corresponding control groups, SOD levels decreased in the groups treated with low-dose presarcopenic supplementation and increased in the high-dose sarcopenic supplemented. GPx levels increased at both doses only in the sarcopenic group compared to the control group. SIRT-1 only increased at low doses in the sarcopenic groups and PGC-1α in both pre-sarcopenia groups compared to the corresponding control. IGF-1 increased compared to the control group at both doses in the pre-sarcopenic group and at high doses in sarcopenic group. Considering the hormetic effects of curcumin, it can be argued that, curcumin supplementation has some positive effects not only at low but also at high doses in both groups. This means that the high doses of curcumin have no negative synergistic effects in addition to oxidative stress during sarcopenia and high-dose supplementation in patients already suffering from high oxidative stress due to sarcopenia is safe and could be considered hormetic.

Keywords: curcumin, hormesis, sarcopenia, muscular atrophy, PGC protein, Sirtuins

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10935 The Effects of Drought and Nitrogen on Soybean (Glycine max (L.) Merrill) Physiology and Yield

Authors: Oqba Basal, András Szabó

Abstract:

Legume crops are able to fix atmospheric nitrogen by the symbiotic relation with specific bacteria, which allows the use of the mineral nitrogen-fertilizer to be reduced, or even excluded, resulting in more profit for the farmers and less pollution for the environment. Soybean (Glycine max (L.) Merrill) is one of the most important legumes with its high content of both protein and oil. However, it is recommended to combine the two nitrogen sources under stress conditions in order to overcome its negative effects. Drought stress is one of the most important abiotic stresses that increasingly limits soybean yields. A precise rate of mineral nitrogen under drought conditions is not confirmed, as it depends on many factors; soybean yield-potential and soil-nitrogen content to name a few. An experiment was conducted during 2017 growing season in Debrecen, Hungary to investigate the effects of nitrogen source on the physiology and the yield of the soybean cultivar 'Boglár'. Three N-fertilizer rates including no N-fertilizer (0 N), 35 kg ha-1 of N-fertilizer (35 N) and 105 kg ha-1 of N-fertilizer (105 N) were applied under three different irrigation regimes; severe drought stress (SD), moderate drought stress (MD) and control with no drought stress (ND). Half of the seeds in each treatment were pre-inoculated with Bradyrhizobium japonicum inoculant. The overall results showed significant differences associated with fertilization and irrigation, but not with inoculation. Increasing N rate was mostly accompanied with increased chlorophyll content and leaf area index, whereas it positively affected the plant height only when the drought was waived off. Plant height was the lowest under severe drought, regardless of inoculation and N-fertilizer application and rate. Inoculation increased the yield when there was no drought, and a low rate of N-fertilizer increased the yield furthermore; however, the high rate of N-fertilizer decreased the yield to a level even less than the inoculated control. On the other hand, the yield of non-inoculated plants increased as the N-fertilizer rate increased. Under drought conditions, adding N-fertilizer increased the yield of the non-inoculated plants compared to their inoculated counterparts; moreover, the high rate of N-fertilizer resulted in the best yield. Regardless of inoculation, the mean yield of the three fertilization rates was better when the water amount increased. It was concluded that applying N-fertilizer to provide the nitrogen needed by soybean plants, with the absence of N2-fixation process, is very important. Moreover, adding relatively high rate of N-fertilizer is very important under severe drought stress to alleviate the drought negative effects. Further research to recommend the best N-fertilizer rate to inoculated soybean under drought stress conditions should be executed.

Keywords: drought stress, inoculation, N-fertilizer, soybean physiology, yield

Procedia PDF Downloads 148
10934 Numerical Simulation of Sloshing Control Using Input Shaping

Authors: Dongjoo Kim

Abstract:

Effective control of sloshing in a liquid container is an important issue to be resolved in many applications. In this study, numerical simulations are performed to design the velocity profile of rectangular container and investigate the effectiveness of input shaping for sloshing control. Trapezoidal profiles of container velocity are chosen to be reference commands and they are convolved with a series of impulses to generate shaped ones that induce minimal residual oscillations. The performances of several input shapers are compared from the viewpoint of transient peak and residual oscillations of sloshing. Results show that sloshing can be effectively controlled by input shaping (Supported by the NRF programs, NRF-2015R1D1A1A01059675, of Korean government).

Keywords: input shaping, rectangular container, sloshing, trapezoidal profile

Procedia PDF Downloads 251
10933 Support Systems for Vehicle Use

Authors: G. González, J. Ramírez, A. Rubiano

Abstract:

This article describes different patented systems for safe use in vehicles based on GPS technology, speed sensors, gyroscopes, maps, communication systems, and monitors, that inform the driver about traffic jam, obstruction in the road, speed limits, among others. Once the information is analyzed and contrasted to final propose new technical needs to be solved.

Keywords: GPS, information technology, telecommunications, communication networks, gyroscope, environmental pollution

Procedia PDF Downloads 458
10932 Effective Internal Control System in the Nasarawa State Tertiary Educational Institutions for Efficiency- A Case of Nasarawa State Polytechnic Lafia

Authors: Dauda Ibrahim Adagye

Abstract:

Effective internal control system in the bursary unit of tertiary educational institutions is geared toward achieving quality teaching, learning, and research environment and as well assist the management of the institutions, particularly when decisions are to be made. While internal control system exists in all institutions, the outlined objectives above are far from being achieved. The paper; therefore, assesses the effectiveness of internal control system in tertiary educational institutions in Nasarawa State, Nigeria with the specific focus on the Nasarawa state Polytechnic, Lafia. The study is survey; hence, a simple closed-ended questionnaire was developed and administered to a sample of twenty-seven (27) member staff from the Bursary and the internal audit unit of the Nasarawa State Polytechnic, Lafia to obtain data for analysis purposes and to test the study hypothesis. Responses from the questionnaire were analyzed using a simple percentage and chi-square. Findings shows that the right people are not assigned to the right job in the department, budget, and management accounting were never used in the institution’s operations and checking of subordinate by their superior officers is not regular. This renders the current internal control structure of the Polytechnic as ineffective and weak. The paper therefore, recommends that: transparency should be seen as significant, as the institution work toward meeting its objectives, therefore, it means that the right staff is assigned to the right job and regular checking of the subordinates by their ensued superiors.

Keywords: internal control, tertiary educational intuitions, efficiency

Procedia PDF Downloads 202
10931 A Survey of Crowdsourcing Technology

Authors: Qianjia Cheng, Hongquan Jiang

Abstract:

Crowdsourcing solves the problems that computers can't handle by integrating computers and the Internet. Its extensive knowledge sources, high efficiency and high quality, make crowdsourcing attract wide attention in industry and academia in recent years. The development of online crowdsourcing platforms such as Clickworker and Amazon Mechanical Turk(Mturk) tend to mature gradually. This paper sorts out the concept of crowdsourcing, sorts out the workflow of competitive crowdsourcing, summarizes the related technologies of crowdsourcing based on the workflow, quality control, cost control and delay control, introduces the typical crowdsourcing platform. Finally, we highlight some open problems of the current crowdsourcing and present some future research direction in this area.

Keywords: application, crowdsourcing, crowdsourcing platform, system architecture

Procedia PDF Downloads 63