Search results for: coastal erosion control

Authors: Mohammad Matin

Abstract:

Nowadays, one of the basic problems of higher education is a significant decline in the quality of education and reduction in efficiency of training. These research and studies are aiming to assess affecting factors of the erosion of academic quality, including educational environmental and content, social and economic factors, elements of the training, elements of education, family factors, from the perspective of students. The result of such improper competition, totally, has led to the decline of education quality in higher education centers, and in many aspects. The results showed a significant difference between male and female students' perspective for two areas of social and economic factors.

Keywords: higher education, decline, the quality of education, student

Procedia PDF Downloads 323

Authors: Nan Ding, Motoki Shino, Nobuyasu Tomokuni, Genki Murata

Abstract:

The wheelchair is the major means of transport for physically disabled people. However, it cannot overcome architectural barriers such as curbs and stairs. In this paper, the authors proposed a method to avoid falling down of a wheeled inverted pendulum type robotic wheelchair for climbing stairs. The problem of this system is that the feedback gain of the wheels cannot be set high due to modeling errors and gear backlash, which results in the movement of wheels. Therefore, the wheels slide down the stairs or collide with the side of the stairs, and finally the wheelchair falls down. To avoid falling down, the authors proposed a slider control strategy based on skyhook model in order to decrease the movement of wheels, and a rotary link control strategy based on the staircase dimensions in order to avoid collision or slide down. The effectiveness of the proposed fall avoidance control strategy was validated by ODE simulations and the prototype wheelchair.

Keywords: EPW, fall avoidance control, skyhook, wheeled inverted pendulum

Procedia PDF Downloads 318

Authors: W. Du, X. Wang, Jun Cao, H. F. Wang

Abstract:

Due to the randomness and uncertainty of wind energy, modern power systems integrating large-scale wind generation will be significantly impacted in terms of system performance and technical challenges. System inertia with high wind penetration is decreasing when conventional thermal generators are gradually replaced by wind turbines, which do not naturally contribute to inertia response. The power imbalance caused by wind power or demand fluctuations leads to the instability of system frequency. Accordingly, the need to attach the supplementary virtual inertia control to wind farms (WFs) strongly arises. When multi-wind farms are connected to the grid simultaneously, the selection of which critical WFs to install the virtual inertia control is greatly important to enhance the stability of system frequency. By building the small signal model of wind power systems considering frequency regulation, the installation locations are identified by the geometric measures of the mode observability of WFs. In addition, this paper takes the impacts of grid topology and selection of feedback control signals into consideration. Finally, simulations are conducted on a multi-wind farms power system and the results demonstrate that the designed virtual inertia control method can effectively assist the frequency regulation.

Keywords: frequency regulation, virtual inertia control, installation locations, observability, wind farms

Procedia PDF Downloads 384

Authors: Yangming Zhu, Mingming Guo, Xiaozan Wang

Abstract:

Introduction: The purpose of this study is to integrate functional training into physical education to test the effectiveness of functional training in improving the physical fitness (PF) and sport skills (SS) of female college students. Methods: A total of 54 female college students from East China Normal University were selected for this study (27 in the experimental group and 27 in the control group), and 13 weeks of the experimental intervention was conducted during the semester. During the experimental period, the experimental group was functionally trained for 1 hour per week. The control group performed one-hour weekly sports (such as basketball, football, etc.) as usual. Before and after the experiment, the national students' physical fitness test was used to test the PF of the experimental group and the control group, and the SS of the experimental group and the control group were tested before and after the intervention. Then using SPSS and Excel to organize and analyze the data. Results: The independent sample T-test showed that there was no significant difference in the PF and SS between the experimental group and the control group before the experiment (T PF=71.86, p PF> 0.05, Tₛₛ=82.41,pₛₛ > 0.05); After the experiment, the PF of the experimental group was significantly higher than that of the control group (T Improve=71.86, p Improve < 0.05); after the experiment, the SS of the experimental group was significantly higher than that of the control group (Tₛₛ = 1.31, pₛₛ <0.01) Conclusions: Integrating functional training into physical education can improve the PF of female college students. At the same time, the integration of functional training into physical education can also effectively improve the SS of female college students. Therefore, it is suggested that functional training be integrated into the daily physical education of female college students so as to improve their PF and SS.

Keywords: functional training, physical fitness, sport skills, female college students

Procedia PDF Downloads 120

Authors: Sayed M. Ahmed, Sawsan S. Darwish, Nagib A. Elmarzugi, Mohammad A. Al-Dosari, Mahmoud A. Adam, Nadia A. Al-Mouallimi

Abstract:

Historical stone surfaces and architectural heritage may undergo unwanted changes due to the exposure to many physical and chemical deterioration factors, the innovative properties of the nano - materials can have advantageous application in the restoration and conservation of the cultural heritage with relation to the tailoring of new products for protection and consolidation of stone. The current work evaluates the effectiveness of inorganic compatible treatments; based on nanosized particles of silica (SiO2) dispersed in silicon based product, commonly used as a water-repellent/ consolidation for the construction materials affected by different kinds of decay. The nanocomposites obtained by dispersing the silica nanoparticles in polymeric matrices SILRES® BS OH 100 (solventless mixtures of ethyl silicates), in order to obtain a new nanocomposite, with hydrophobic and consolidation properties, to improve the physical and mechanical properties of the stone material. The nanocomposites obtained and pure SILRES® BS OH 100 were applied by brush Experimental stone blocks. The efficacy of the treatments has been evaluated after consolidation and artificial Thermal aging, through capillary water absorption measurements, Ultraviolet-light exposure to evaluate photo-induced and the hydrophobic effects of the treated surface, Scanning electron microscopy (SEM) examination is performed to evaluate penetration depth, re-aggregating effects of the deposited phase and the surface morphology before and after artificialaging. Sterio microscopy investigation is performed to evaluate the resistant to the effects of the erosion, acids and salts. Improving of stone mechanical properties were evaluated by compressive strength tests, colorimetric measurements were used to evaluate the optical appearance. All the results get together with the apparent effect that, silica/polymer nanocomposite is efficient material for the consolidation of artistic and architectural sandstone monuments, completely compatible, enhanced the durability of sandstone toward thermal and UV aging. In addition, the obtained nanocomposite improved the stone mechanical properties and the resistant to the effects of the erosion, acids and salts compared to the samples treated with pure SILRES® BS OH 100 without silica nanoparticles.

Keywords: colorimetric measurements, compressive strength, nanocomposites, porous stone consolidation, silica nanoparticles, sandstone

Procedia PDF Downloads 242

Authors: Chinazo Onyeka Eziuzo

Abstract:

This work presents the simulation and control of the flywheel system in the rotor of a wind turbine using Simulink and OpenFAST for assessing the effect on the mechanical loads. This concept allows the flywheel system to serve two main tasks: supporting the power system and mitigating the mechanical loads in the wind turbine. These tasks are grouped into four control scenarios; scenario 1 represents steadying the power infeed in the Flywheel, scenario 2 represents steadying power with FW and grid loss, scenario 3 represents mitigating excitations from gravity, and scenario 4 represents damping in-plane blade vibrations. The s-function of the OpenFAST model was used to substitute the given 1st Eigen mode model of the WT. After that, the simulations were run for the above-listed scenarios. Additionally, the effects of the control options on the mechanical loads were assessed, and it was established that the FW system assists in steadying infeed power and mechanical load mitigation.

Keywords: simulation, control, wind turbine, OpenFAST

Procedia PDF Downloads 99

Authors: Waqqas-ur-Rehman Butt, Martin Servin, Marion Pause

Abstract:

In recent years, object detection has gained much attention and very encouraging research area in the field of computer vision. The robust object boundaries detection in an image is demanded in numerous applications of human computer interaction and automated surveillance systems. Many methods and approaches have been developed for automatic object detection in various fields, such as automotive, quality control management and environmental services. Inappropriately, to the best of our knowledge, object detection under illumination with shadow consideration has not been well solved yet. Furthermore, this problem is also one of the major hurdles to keeping an object detection method from the practical applications. This paper presents an approach to automatic object detection in images under non-standardized environmental conditions. A key challenge is how to detect the object, particularly under uneven illumination conditions. Image capturing conditions the algorithms need to consider a variety of possible environmental factors as the colour information, lightening and shadows varies from image to image. Existing methods mostly failed to produce the appropriate result due to variation in colour information, lightening effects, threshold specifications, histogram dependencies and colour ranges. To overcome these limitations we propose an object detection algorithm, with pre-processing methods, to reduce the interference caused by shadow and illumination effects without fixed parameters. We use the Y CrCb colour model without any specific colour ranges and predefined threshold values. The segmented object regions are further classified using morphological operations (Erosion and Dilation) and contours. Proposed approach applied on a large image data set acquired under various environmental conditions for wood stack detection. Experiments show the promising result of the proposed approach in comparison with existing methods.

Keywords: image processing, illumination equalization, shadow filtering, object detection

Procedia PDF Downloads 204

Authors: Mahdi Zolfaghari, Seyed Hossein Hosseinian, Hossein Askarian Abyaneh, Mehrdad Abedi

Abstract:

This paper presents a virtual active power filter (VAPF) using vehicle to grid (V2G) technology to maintain power quality requirements. The optimal discrete operation of the power converter of electric vehicle (EV) is based on recognizing desired switching states using the model predictive control (MPC) algorithm. A fast dynamic response, lower total harmonic distortion (THD) and good reference tracking performance are realized through the presented control strategy. The simulation results using MATLAB/Simulink validate the effectiveness of the scheme in improving power quality as well as good dynamic response in power transferring capability.

Keywords: electric vehicle, model predictive control, power quality, V2G technology, virtual active power filter

Procedia PDF Downloads 408

Authors: Nurtekin Erkmen, Turgut Kaplan, Halil Taskin, Ahmet Sanioglu, Gokhan Ipekoglu

Abstract:

The aim of this study was to determine the effects of an 8 week soccerspecific technical training with limited vision perception on postural control and technical parameters in 10-12 aged soccer players. Subjects in this study were 24 male young soccer players (age: 11.00 ± 0.56 years, height: 150.5 ± 4.23 cm, body weight: 41.49 ± 7.56 kg). Subjects were randomly divided as two groups: Training and control. Balance performance was measured by Biodex Balance System (BBS). Short pass, speed dribbling, 20 m speed with ball, ball control, juggling tests were used to measure soccer players’ technical performances with a ball. Subjects performed soccer training 3 times per week for 8 weeks. In each session, training group with limited vision perception and control group with normal vision perception committed soccer-specific technical drills for 20 min. Data analyzed with t-test for independent samples and Mann-Whitney U between groups and paired t-test and Wilcoxon test between pre-posttests. No significant difference was found balance scores and with eyes open and eyes closed and LOS test between training and control groups after training (p>0.05). After eight week of training there are no significant difference in balance score with eyes open for both training and control groups (p>0.05). Balance scores decreased in training and control groups after the training (p<0.05). The completion time of LOS test shortened in both training and control groups after training (p<0.05). The training developed speed dribbling performance of training group (p<0.05). On the other hand, soccer players’ performance in training and control groups increased in 20 m speed with a ball after eight week training (p<0.05). In conclusion; the results of this study indicate that soccer-specific training with limited vision perception may not improves balance performance in 10-12 aged soccer players, but it develops speed dribbling performance.

Keywords: Young soccer players, vision perception, postural control, technical

Procedia PDF Downloads 456

Authors: Dib Djalel, Mordjaoui Mourad

Abstract:

The current trend towards the exploitation of various renewable energy resources has become indispensable, so it is important to improve the efficiency and reliability of the GPV photovoltaic systems. Maximum Power Point Tracking (MPPT) plays an important role in photovoltaic power systems because it maximize the power output from a PV system for a given set of conditions. This paper presents a new fuzzy logic control based MPPT algorithm for solar panel. The solar panel is modeled and analyzed in Matlab/Simulink. The Solar panel can produce maximum power at a particular operating point called Maximum Power Point(MPP). To produce maximum power and to get maximum efficiency, the entire photovoltaic panel must operate at this particular point. Maximum power point of PV panel keeps on changing with changing environmental conditions such as solar irradiance and cell temperature. Thus, to extract maximum available power from a PV module, MPPT algorithms are implemented and Perturb and Observe (P&O) MPPT and fuzzy logic control FLC, MPPT are developed and compared. Simulation results show the effectiveness of the fuzzy control technique to produce a more stable power.

Keywords: MPPT, photovoltaic panel, fuzzy logic control, modeling, solar power

Procedia PDF Downloads 468

Authors: Tursunay Vassilina, Aigerim Shibikeyeva, Adilet Sakhbek

Abstract:

Research has been carried out to study the influence of modified zeolite fertilizers on the quantitative and qualitative indicators of cabbage variety Nezhenka. The use of zeolite and mineral fertilizers had a positive effect on both the yield and quality indicators of the studied crop. The maximum increase in yield from fertilizers was 16.5 t/ha. Application of both zeolite and fertilizer increased the dry matter, sugar and vitamin C content of cabbage heads. It was established that the cabbage contains an amount of nitrates that is safe for human health. Among vegetable crops, cabbage has both food and feed value. One of the limiting factors in the sale of vegetable crops is the degradation of soil fertility due to depletion of nutrient reserves and erosion processes, and non-compliance with fertilizer application technologies. Natural zeolites are used as additives to mineral fertilizers for application in the field, which makes it possible to reduce their doses to minimal quantities. Zeolites improve the agrophysical and agrochemical properties of the soil and the quality of plant products. The research was carried out in a field experiment, carried out in 3 repetitions, on dark chestnut soil in 2023. The soil (pH = 7.2-7.3) of the experimental plot is dark chestnut, the humus content in the arable layer is 2.15%, gross nitrogen 0.098%, phosphorus, potassium 0.225 and 2.4%, respectively. The object of the study was the late cabbage variety Nezhenka. Scheme for applying fertilizers to cabbage: 1. Control (without fertilizers); 2. Zeolite 2t/ha; 3. N45P45K45; 4. N90P90K90; 5. Zeolite, 2 t/ha + N45P45K45; 6. Zeolite, 2 t/ha + N90P90K90. Yield accounting was carried out on a plot-by-plot basis manually. In plant samples, the following was determined: dry matter content by thermostatic method (at 105ºC); sugar content by Bertrand titration method, nitrate content by 1% diphenylamine solution, vitamin C by titrimetric method with acid solution. According to the results, it was established that the yield of cabbage was high – 42.2 t/ha in the treatment Zeolite, 2 t/ha + N90P90K90. When determining the biochemical composition of white cabbage, it was found that the dry matter content was 9.5% and increased with fertilized treatments. The total sugar content increased slightly with the use of zeolite (5.1%) and modified zeolite fertilizer (5.5%), the vitamin C content ranged from 17.5 to 18.16%, while in the control, it was 17.21%. The amount of nitrates in products also increased with increasing doses of nitrogen fertilizers and decreased with the use of zeolite and modified zeolite fertilizer but did not exceed the maximum permissible concentration. Based on the research conducted, it can be concluded that the application of zeolite and fertilizers leads to a significant increase in yield compared to the unfertilized treatment; contribute to the production of cabbage with good and high quality indicators.

Keywords: cabbage, dry matter, nitrates, total sugar, yield, vitamin C

Procedia PDF Downloads 59

Authors: Baki Aydin, Erkan Gumus

Abstract:

The aim of the present study was to investigate the effects of replacing dietary soybean meal by dried grains with solubles (DDGS) on liver histology of rainbow trout, Oncorhynchus mykiss. Five isoproteic (∼45% crude protein) and isocaloric (∼3570 kcal/kg digestible energy) diets were formulated: Conrol-1 (Fish meal control), Control-2, DDGS33, DDGS66 and DDGS100 which included 0%, 0%, 10%, 20% and 30% DDGS, respectively. Triplicate groups of fish with an average weight of 20.46 g were fed three times a day until apparent satiation during 84 days. The obtained results showed that diameters of hepatocyte nuclei were not statistically different among the groups. The histological examination of liver sections from the fish fed the Control-1 diet showed normal histology, mild cytoplasm vacuoles and appears to be central to hepatocyte nuclei. Fish fed diets containing soybean meal and DDGS presented variable levels of cytoplasmic vacuolization and some with eccentric hepatocyte nuclei. But, fish fed diet soybean meal based control (Control-2) showed the highest hepatocyte nuclei displacement, and cytoplasm vacuoles compared the DDGS30 diet. DDGS20 and DDGS30 fish also showed more regular hepatocytes than in Control-2 fish. The results of this study demonstrated that fish fed diets containing increasing DDGS levels exhibited less histomorphological changes compared the Control-2 diet.

Keywords: DDGS, soybean meal, rainbow trout, hepatocyte

Procedia PDF Downloads 139

Authors: E. Kaygan, A. Gatto

Abstract:

An investigation of adaptable winglets for morphing aircraft control and performance is described in this paper. The concepts investigated consist of various winglet configurations fundamentally centred on a baseline swept wing. The impetus for the work was to identify and optimize winglets to enhance controllability and the aerodynamic efficiency of a small unmanned aerial vehicle. All computations were performed with Athena Vortex Lattice modelling with varying degrees of twist, swept, and dihedral angle considered. The results from this work indicate that if adaptable winglets were employed on small scale UAV’s improvements in both aircraft control and performance could be achieved.

Keywords: aircraft, rolling, wing, winglet

Procedia PDF Downloads 446

Authors: T. Abdelkrim, K. Benamrane, B. Bezza, Aeh Benkhelifa, A. Borni

Abstract:

This paper proposes a regulation method of back-to-back connected three-level converters in order to reduce the torque ripple in induction motor. First part is dedicated to the presentation of the feedback control of three-level PWM rectifier. In the second part, three-level NPC voltage source inverter balancing DC bus algorithm is presented. A theoretical analysis with a complete simulation of the system is presented to prove the excellent performance of the proposed technique.

Keywords: back-to-back connection, feedback control, neutral-point balance, three-level converter, torque ripple

Procedia PDF Downloads 480

Authors: P. Sawatnatee, S. Udomsuk, K-N. Areerak, K-L. Areerak, A. Srikaew

Abstract:

The paper presents how to design the indirect vector control of three-phase induction motor drive systems using the artificial intelligence technique called the adaptive tabu search. The results from the simulation and the experiment show that the drive system with the controller designed from the proposed method can provide the best output speed response compared with those of the conventional method. The controller design using the proposed technique can be used to create the software package for engineers to achieve the optimal controller design of the induction motor speed control based on the indirect vector concept.

Keywords: indirect vector control, induction motor, adaptive tabu search, control design, artificial intelligence

Procedia PDF Downloads 385

Authors: Michael Daly

Abstract:

Background/Aims: The interplay of childhood self-control and early life social background in predicting adult health is currently unclear. We drew on rich data from two large nationally representative cohort studies to test whether individual differences in childhood self-control may: (i) buffer the health impact of social disadvantage, (ii) act as a mediating pathway underlying the emergence of health disparities, or (iii) compensate for the health consequences of socioeconomic disadvantage across the lifespan. Methods: We examined data from over 25,000 participants from the British Cohort Study (BCS) and the National Child Development Study (NCDS). Child self-control was teacher-rated at age 10 in the BCS and ages 7/11 in the NCDS. The Early life social disadvantage was indexed using measures of parental education, occupational prestige, and housing characteristics (i.e. housing tenure, home crowding). A range of health outcomes was examined: the presence of chronic conditions, whether illnesses were limiting, physiological dysregulation (gauged by clinical indicators), mortality, and perceptions of pain, psychological distress, and general health. Results: Childhood self-control and social disadvantage predicted each measure of adult health, with similar strength on average. An examination of mediating factors showed that adult smoking, obesity, and socioeconomic status explained the majority of these linkages. There was no systematic evidence that self-control moderated the health consequences of early social disadvantage and limited evidence that self-control acted as a key pathway from disadvantage to later health. Conclusions: Childhood self-control predicts adult health and may compensate for early life social disadvantage by shaping adult health behaviour and social status.

Keywords: personality and health, social disadvantage, health psychology, life-course development

Procedia PDF Downloads 209

Authors: Walid S. Alfuhaid, Saud A. Alghamdi, John M. Watkins, M. Edwin Sawan

Abstract:

Designing a controller for stochastic decentralized interconnected large scale systems usually involves a high degree of complexity and computation ability. Noise, observability, and controllability of all system states, connectivity, and channel bandwidth are other constraints to design procedures for distributed large scale systems. The quasi-steady state model investigated in this paper is a reduced order model of the original system using singular perturbation techniques. This paper results in an optimal control synthesis to design an observer based feedback controller by standard stochastic control theory techniques using Linear Quadratic Gaussian (LQG) approach and Kalman filter design with less complexity and computation requirements. Numerical example is given at the end to demonstrate the efficiency of the proposed method.

Keywords: decentralized, optimal control, output, singular perturb

Procedia PDF Downloads 353

Authors: Alireza Vakili, Shahab Ehtesham, Mohsen Danesh Mesgaran, Mahdi Paktinat

Abstract:

The goal of this study is to determine the chemical compounds of brown Iranian propolis(BIP) extracts and to show flavonoids and phenol effects on nitrogen ammonia (NH3-N) in in vitro. Experimental samples were including two diets with different concentrate: forage ratio (80:20 and 60:40) with eight treatments (1:Control diet 60:40 without BIP,2: 60:40 diet with 25% BIP, 3:60:40 diet with 50% BIP, 4: 60:40 diet with 75% BIP,5: Control diet 80:20 without BIP,6: 80:20 diet with 25% BIP,7: 80:20 diet with 50% BIP and 8: 80:20 diet with 75% BIP) and eight repeats. The trial was analyzed considering a completely randomized design by the GLM procedure of SAS 9.1. Means among treatment were compared by Tukey test. The results of this study showed that in food with 80:20 (concentrate: forage), adding BIP 25% did not statistically change NH3-N (p > 0.05) compared to the control treatment but there was a significant difference (p < 0.05) between the effect of BIP 50% on NH3-N compared to the BIP 25% and the control. In diet with 60:40 (concentrate: forage), there was no significant difference between the effect of BIP 25% on NH3-N and the control, nor was there a significant difference between the effect of BIP 50% and 75%, while a significant difference (p < 0.05) between BIP 50% and 75% and the rest was observed. The propolis extract makes nitrogen ammonia decrease. This may help the nitrogen retain longer in ruminants.

Keywords: brown Iranian propolis, in vitro, nitrogen ammonia, ruminant

Procedia PDF Downloads 465

Authors: Xie Kefeng, Zhang He

Abstract:

For the stability and control demand of offshore small floating platform, a 2-HUS/U parallel mechanism was presented as offshore platform. Inverse kinematics was obtained by institutional constraint equation, and the dynamic model of offshore 2-HUS/U parallel platform was derived based on rigid body’s Lagrangian method. The equivalent moment of inertia, damping and driving force/torque variation of offshore 2-HUS/U parallel platform were analyzed. A numerical example shows that, for parallel platform of given motion, system’s equivalent inertia changes 1.25 times maximally. During the movement of platform, they change dramatically with the system configuration and have coupling characteristics. The maximum equivalent drive torque is 800 N. At the same time, the curve of platform’s driving force/torque is smooth and has good sine features. The control system needs to be adjusted according to kinetic equation during stability and control and it provides a basis for the optimization of control system.

Keywords: 2-HUS/U platform, dynamics, Lagrange, parallel platform

Procedia PDF Downloads 332

Authors: Edward Nartey

Abstract:

Although sustainability management control (SMC) systems provide information that enhances corporate sustainability decisions, reviews on the SMC implications for sustainable supply chains (SCs) demonstrate a wide research gap, particularly the sustainability performance of healthcare SCs in unusual times. This study provides preliminary empirical evidence on the level of SMC adoption and the decision-making implications for the Tripple Bottom Line (TBL) principles of SC sustainability of Ghanaian public healthcare institutions (PHIs). Using a sample of 226 public health managers, the results show that sustainable formal control has a positive and significant impact on economic sustainability but an insignificant effect on social and environmental sustainability. In addition, a positive relationship was established between informal controls and economic and environmental sustainability but an insignificant relationship with social sustainability. Although the findings highlight the prevalence of the SMC system being prioritized over regular MCS in crisis situations, the MCSs are inadequate in promoting PHIs' sustainable behaviours in SCs. It also provides little empirical evidence on the effective enhancement of the TBL principle of SC sustainability perhaps because the SMC is in misalignment with the TBL principle in crisis situations. Thus, in crisis situations, PHIs need to redesign their MCSs to support the integration of sustainability issues in SCs.

Keywords: sustainability management control, informal control, formal control, sustainable supply chain performance

Procedia PDF Downloads 38

Authors: Nasreen Basoudan, Andrea Tales, Frederic Boy

Abstract:

Non-clinical anxiety may be comprised of state anxiety - temporarily experienced anxiety related to a specific situation, and trait anxiety - a longer lasting response or a general disposition to anxiety. While temporary and occasional anxiety whether as a mood state or personality dimension is normal, nonclinical anxiety may influence many more components of information processing than previously recognized. In ageing and dementia-related research, disease characterization now involves attempts to understand a much wider range of brain function such as loss of inhibitory control, as against the more common focus on memory and cognition. However, in many studies, the tendency has been to include individuals with clinical anxiety disorders while excluding persons with lower levels of state or trait anxiety. Loss of inhibitory cognitive control can lead to behaviors such as aggression, reduced sensitivity to others, sociopathic thoughts and actions. Anxiety has also been linked to inhibitory control, with research suggesting that people with anxiety are less capable of inhibiting their emotions than the average person. This study investigates the relationship between anxiety and loss of inhibitory control in younger and older adults, using a variety of questionnaires and computers-based tests. Based on the premise that irrespective of classification, anxiety is associated with a wide range of physical, affective, and cognitive responses, this study explores evidence indicative of the potential influence anxiety per se on loss of inhibitory control, in order to contribute to discussion and appropriate consideration of anxiety-related factors in methodological practice.

Keywords: anxiety, ageing, dementia, inhibitory control

Procedia PDF Downloads 228

Authors: T. Vamsee Kiran, A. Gopi

Abstract:

The undesired torque and flux ripple may occur in conventional direct torque control (DTC) induction motor drive. DTC can improve the system performance at low speeds by continuously tuning the regulator by adjusting the Kp, Ki values. In this differential evolution (DE) is proposed to adjust the parameters (Kp, Ki) of the speed controller in order to minimize torque ripple, flux ripple, and stator current distortion.The DE based PI controller has resulted is maintaining a constant speed of the motor irrespective of the load torque fluctuations.

Keywords: differential evolution, direct torque control, PI controller

Procedia PDF Downloads 415

Authors: Naziru Suleiman

Abstract:

The ever increasing cases of financial frauds and corporate accounting scandals in recent years have raised more concern on the operation of internal control mechanisms and performance of the internal audit departments in organizations. In most cases the seeming presence of both the internal control system and internal audit in organizations do not prove useful as frauds errors and irregularities are being perpetuated. The aim of this study, therefore, is to assess the role of internal audit in achieving the objectives of internal control system of federal hospitals in Kano State from the perception of the respondents. The study used survey research design and generated data from primary source by means of questionnaire. A total number of 100 copies of questionnaire were administered out of which 68 were duly completed and returned. Cronbach’s alpha was used to test the internal validity of the various items in the constructs. Descriptive statistics, chi-square test, Mann Whitney U test and Kruskal Wallis ANOVA were employed for the analysis of data. The study finds that from the perception of the respondents, internal audit departments in Federal Hospitals in Kano State are effective and that they contribute positively to the overall attainment of the objectives of internal control system of these hospitals. There is no significant difference found on the views of the respondents from the three hospitals. Hence, the study concludes that strong and functional internal audit department is a basic requirement for effectiveness of operations of the internal control system. In the light of the findings, it is recommended that internal audit should continue to ensure that the objectives of internal control system of these hospitals are achieved through proper and adequate evaluation and review of the system.

Keywords: internal audit, internal control, federal hospitals, financial frauds

Procedia PDF Downloads 334

Authors: Hanqing Yang, Xiang Meng, Qi Li, Weirong Chen

Abstract:

The SOC (state of charge) based droop control has limitations on the load power sharing among different energy storage units, due to the line impedance. In this paper, a distributed control strategy for dispersed energy storage units in the DC microgrid based on discrete consensus is proposed. Firstly, a sparse information communication network is built. Thus, local controllers can communicate with its neighbors using voltage, current and SOC information. An average voltage of grid can be evaluated to compensate voltage offset by droop control, and an objective virtual resistance fulfilling above requirement can be dynamically calculated to distribute load power according to the SOC of the energy storage units. Then, the stability of the whole system and influence of communication delay are analyzed. It can be concluded that this control strategy can improve the robustness and flexibility, because of having no center controller. Finally, a model of DC microgrid with dispersed energy storage units and loads is built, the discrete distributed algorithm is established and communication protocol is developed. The co-simulation between Matlab/Simulink and JADE (Java agent development framework) has verified the effectiveness of proposed control strategy.

Keywords: dispersed energy storage units, discrete consensus algorithm, state of charge, communication delay

Procedia PDF Downloads 260

Authors: Abdmohammad Mousavi, Mohsen Shams, Mehdi Akbartabar Toori, Ali Mousavizadeh, Mohammad Ali Morowatisharifabad

Abstract:

The effectiveness of Transtheoretical Model (TTM) on nutritional behavior change and lose weight has been subject to questions by some studies. The objective of this study was to determine the effect of nutritional behavior change and lose weight interventions based on TTM in obese and overweight women. This experimental study that was a 8 months trial nutritional behavior change and weight loss program based on TTM with two conditions and pre–post intervention measurements weight mean. 299 obese and overweight 20-44 years old women were selected from two health centers include training (142) and control (157) groups in Yasuj, a city in south west of Iran. Data were analyzed using paired T-test and One–Way ANOVA tests. In baseline, adherence with nutritional healthy behavior in training group(9.4%) compare with control(38.8%) were different significantly(p=.003), weight mean of training(Mean=78.02 kg, SD=11.67) compared with control group(Mean=77.23 kg, SD=10.25) were not (P=.66). In post test, adherence with nutritional healthy behavior in training group(70.1%) compare with control (37.4%) were different significantly (p=.000), weight mean of training (Mean=74.65 kg, SD=10.93, p=.000) compare with pre test were different significantly and control (Mean=77.43 kg, SD=10.43, p=.411) were not. The training group has lost 3.37 kg weight, whereas the control group has increased .2 kg weight. These results supported the applicability of the TTM for women weight lose intervention.

Keywords: nutritional behavior, Transtheoretical Model, weight lose, women

Procedia PDF Downloads 470

Authors: Sunsoo Kim, Niladri Das, Raktim Bhattacharya

Abstract:

This paper addresses modeling and control of a six-degree-of-freedom unmanned aerial vehicle capable of vertical take-off and landing in the presence of wind disturbances. We design a hybrid vehicle that combines the benefits of both the fixed-wing and the rotary-wing UAVs. A non-linear model for the hybrid vehicle is rapidly built, combining rigid body dynamics, aerodynamics of wing, and dynamics of the motor and propeller. Further, we design a H₂ optimal controller to make the UAV robust to wind disturbances. We compare its results against that of proportional-integral-derivative and linear-quadratic regulator based control. Our proposed controller results in better performance in terms of root mean squared errors and time responses during two scenarios: hover and level- flight.

Keywords: hybrid UAVs, VTOL, aircraft modeling, H2 optimal control, wind disturbances

Procedia PDF Downloads 138

Authors: S. M. Ashikur Elahee, Md. Zahidur Rahman, Md. Shofiqur Rahman

Abstract:

This study evaluated the impact of different water interventions under WASH program on access of household's to safe drinking water. Following survey method, the study was carried out in two Upazila of South-west coastal region of Bangladesh namely Koyra from Khulna and Shymnagar from Satkhira district. Being an explanatory study, a total of 200 household's selected applying random sampling technique were interviewed using a structured interview schedule. The predicted probability suggests that around 62 percent household's are out of year-round access to safe drinking water whereby, only 25 percent household's have access at SPHERE standard (913 Liters/per person/per year). Besides, majority (78 percent) of the household's have not accessed at both indicators simultaneously. The distance from household residence to the water source varies from 0 to 25 kilometer with an average distance of 2.03 kilometers. The study also reveals that the increase in monthly income around BDT 1,000 leads to additional 11 liters (coefficient 0.01 at p < 0.1) consumption of safe drinking water for a person/year. As expected, lining up time has significant negative relationship with dependent variables i.e., for higher lining up time, the probability of getting access for both SPHERE standard and year round access variables becomes lower. According to ordinary least square (OLS) regression results, water consumption decreases at 93 liters for per person/year of a household if one member is added to that household. Regarding water consumption intensity, ordered logistic regression (OLR) model shows that one-minute increase of lining up time for water collection tends to reduce water consumption intensity. On the other hand, as per OLS regression results, for one-minute increase of lining up time, the water consumption decreases by around 8 liters. Considering access to Deep Tube Well (DTW) as a reference dummy, in OLR, the household under Pond Sand Filter (PSF), Shallow Tube Well (STW), Reverse Osmosis (RO) and Rainwater Harvester System (RWHS) are respectively 37 percent, 29 percent, 61 percent and 27 percent less likely to ensure year round access of water consumption. In line of health impact, different type of water born diseases like diarrhea, cholera, and typhoid are common among the coastal community caused by microbial impurities i.e., Bacteria, Protozoa. High turbidity and TDS in pond water caused by reduction of water depth, presence of suspended particle and inorganic salt stimulate the growth of bacteria, protozoa, and algae causes affecting health hazard. Meanwhile, excessive growth of Algae in pond water caused by excessive nitrate in drinking water adversely effects on child health. In lieu of ensuring access at SPHERE standard, we need to increase the number of water interventions at reasonable distance, preferably a half kilometer away from the dwelling place, ensuring community peoples involved with its installation process where collectively owned water intervention is found more effective than privately owned. In addition, a demand-responsive approach to supply of piped water should be adopted to allow consumer demand to guide investment in domestic water supply in future.

Keywords: access, impact, safe drinking water, Sphere standard, water interventions

Procedia PDF Downloads 210

Authors: S. Ben Brahim, T. H. Vuong, J. David, R. Bouallegue, M. Pietrzak-David

Abstract:

Electrical machine monitoring is important to protect motor from unexpected problems. Today, using wireless communication for electrical machines is interesting for both real time monitoring and diagnostic purposes. In this paper, we propose a system based on wireless communication IEEE 802.11 to control electrical machine. IEEE 802.11 standard is recommended for this type of applications because it provides a faster connection, better range from the base station, and better security. Therefore, our contribution is to study a new technique to control and monitor the rotating electrical machines (motors, generators) using wireless communication. The reliability of radio channel inside rotating electrical machine is also discussed. Then, the communication protocol, software and hardware design used for the proposed system are presented in detail and the experimental results of our system are illustrated.

Keywords: control, DFIM machine, electromagnetic field, EMC, IEEE 802.11, monitoring, rotating electrical machines, wireless communication

Procedia PDF Downloads 682

Authors: Yik Sin Chan, Nam Weng Sit, Fook Yee Chye, van Ofwegen Leen, de Voogd Nicole, Kong Soo Khoo

Abstract:

Chikungunya fever is an arboviral disease transmitted by the Aedes mosquitoes. It has resulted in epidemics of the disease in tropical countries in the Indian Ocean and South East Asian regions. The recent spread of this disease to the temperate countries such as France and Italy, coupled with the absence of vaccines and effective antiviral drugs make chikungunya fever a worldwide health threat. This study aims to investigate the anti-chikungunya virus activity of selected marine organism samples collected from Malaysian coastal areas, including seaweeds (Caulerpa racemosa, Caulerpa sertularioides and Kappaphycus alvarezii), a soft coral (Lobophytum microlobulatum) and a sponge (Spheciospongia vagabunda). Following lyophilization (oven drying at 40C for K. alvarezii) and grinding to powder form, each sample was subjected to sequential solvent extraction using hexane, chloroform, ethyl acetate, ethanol, methanol and distilled water in order to extract bioactive compounds. The antiviral activity was evaluated using monkey kidney epithelial (Vero) cells infected with the virus (multiplicity of infection=1). The cell viability was determined by Neutral Red uptake assay. 70% of the 30 extracts showed weak inhibitory activity with cell viability ≤30%. Seven of the extracts exhibited moderate inhibitory activity (cell viability: 31%-69%). These were the chloroform, ethyl acetate, ethanol and methanol extracts of C. racemosa; chloroform and ethyl acetate extracts of L. microlobulatum; and the chloroform extract of C. sertularioides. Only the hexane and ethanol extracts of L. microlobulatum showed strong inhibitory activity against the virus, resulting in cell viabilities (mean±SD; n=3) of 73.3±2.6% and 79.2±0.9%, respectively. The corresponding mean 50% effective concentrations (EC50) for the extracts were 14.2±0.2 and 115.3±1.2 µg/mL, respectively. The ethanol extract of the soft coral L. microlobulatum appears to hold the most promise for further characterization of active principles as it possessed greater selectivity index (SI>5.6) compared to the hexane extract (SI=2.1).

Keywords: antiviral, seaweed, sponge, soft coral, vero cell

Procedia PDF Downloads 271

Authors: I. Valdez, J. Perdomo, M. Colindres, N. Castro

Abstract:

Today, digital servo systems are extensively used in industrial manufacturing processes, robotic applications, vehicles and other areas. In such control systems, control action is provided by digital controllers with different compensation algorithms, which are designed to meet specific requirements for a given application. Due to the constant search for optimization in industrial processes, it is of interest to design digital controllers that offer ease of realization, improved computational efficiency, affordable return rates, and ease of tuning that ultimately improve the performance of the controlled actuators. There is a vast range of options of compensation algorithms that could be used, although in the industry, most controllers used are based on a PID structure. This research article compares different types of digital compensators implemented in a servo system for DC motor position control. PID compensation is evaluated on its two most common architectures: PID position form (1 DOF), and PID speed form (2 DOF). State feedback algorithms are also evaluated, testing two modern control theory techniques: discrete state observer for non-measurable variables tracking, and a linear quadratic method which allows a compromise between the theoretical optimal control and the realization that most closely matches it. The compared control systems’ performance is evaluated through simulations in the Simulink platform, in which it is attempted to model accurately each of the system’s hardware components. The criteria by which the control systems are compared are reference tracking and disturbance rejection. In this investigation, it is considered that the accurate tracking of the reference signal for a position control system is particularly important because of the frequency and the suddenness in which the control signal could change in position control applications, while disturbance rejection is considered essential because the torque applied to the motor shaft due to sudden load changes can be modeled as a disturbance that must be rejected, ensuring reference tracking. Results show that 2 DOF PID controllers exhibit high performance in terms of the benchmarks mentioned, as long as they are properly tuned. As for controllers based on state feedback, due to the nature and the advantage which state space provides for modelling MIMO, it is expected that such controllers evince ease of tuning for disturbance rejection, assuming that the designer of such controllers is experienced. An in-depth multi-dimensional analysis of preliminary research results indicate that state feedback control method is more satisfactory, but PID control method exhibits easier implementation in most control applications.

Keywords: control, DC motor, discrete PID, discrete state feedback

Procedia PDF Downloads 253