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Dynamic inverse- (DI-) based control technique has been utilized in many applications and proven to be effective. Recently, the inverse dynamic control (IDC), an expansion to the classical DI technique, has been trending with implementation in many areas. It has been proved that IDC is capable of overcoming some limitations in DI-based techniques, particularly in cancellation of useful nonlinearities. This paper extends the implementation of IDC on the positional and speed control of the linear servo cart system. Simulation results further proves that IDC is an effective and robust controller evidently when comparing it with the proportional velocity and lead compensator controller.

Performance evaluation of trajectory tracking for a rotary flexible joint system is demonstrated in this paper. The robust and converse dynamic (RCD) technique is proposed and implemented for this evaluation. This control methodology is of the left inversion type, i.e., the control inputs are obtained by means of plant output error feedback. RCD control encompasses the baseline inverse (BI) control and sliding mode control-based discontinuous control element. The baseline inverse controller enforces the prescribed servo (virtual) constraints that represent the control objectives. The control objectives of the baseline inverse controller are enclosed in the form of servo (virtual) constraints which are inverted using Moore–Penrose Generalized Inverse (MPGI) to solve for the baseline control law. To boost the robust attributes against parametric uncertainties and disturbances, a discontinuous control function is augmented with baseline controller such that semiglobal practical stability is guaranteed in the sense of Lyapunov. To exhibit the effectiveness of RCD control in terms of tracking performance, computer simulations are conducted in Simulink/Matlab environment. Furthermore, the practical implementation is also investigated through a real-time experiment on Quanser’s rotary flexible joint manipulator system. The experimental results obtained by RCD are compared to the conventional sliding mode and fractional-order control techniques.

This paper presents the application of adaptive fuzzy sliding mode control (AFSMC) for the respiratory system to assist the patients facing difficulty in breathing. The ventilator system consists of a blower-hose-patient system and patient’s lung model with nonlinear lung compliance. The AFSMC is based on two components: singleton control action and a discontinuous term. The singleton control action is based on fuzzy logic with adjustable tuning parameters to approximate the perfect feedback linearization control. The switching control law based on the sliding mode principle aims to minimize the estimation error between approximated single fuzzy control action and perfect feedback linearization control. The proposed control strategy manipulated the airway flow delivered by the ventilator such that the peak pressure will remain under critical values in presence of unknown patient-hose-leak parameters and patient breathing effort. The closed-loop stability of AFSMC will be proven in the sense of Lyapunov. For comparative analysis, classical PID and sliding mode controllers are also designed and implemented for mechanical ventilation problems. For performance analysis, numerical simulations were performed on a mechanical ventilator simulator. Simulation results reveal that the proposed controller demonstrates better tracking of targeted airway pressure compared with its counterparts in terms of faster convergence, less overshoot, and small tracking error. Hence, the proposed controller provides useful insight for its application to real-world scenarios.

– In the production of oil and gas wells, hot water, sand and gas is produced along with the hydrocarbon product. Several of these wells/fields produce associated natural can be used to generate power for site consumption. To verify this concept, 2B OPCO oil and gas national company (Formerly GNPOC) in Sudan, at block 4 oil field through Development Department started initiative to enter into a Cooperative Research and Development to demonstrate small scale power generation from utilizing associated gas. This Paper deals with the utilization of associated gas to electrical power. considers amount of associated gas daily being Flared in the atmosphere, It deals with number of fact that although there are essential need of using of traditional fossil fuel as energy source for industrial plants , there are several related concerns associated with the utilizing it in producing energy, utilization the fossil fuel (diesel ,crude oil …etc.) specially in electrical power to cover industrial plant electrical power demands (commercial plants ,factories ,residential , oil & gas fields….etc.) for production and processing of products or supplying services as well as auxiliary power for utilities, fuel cost and fuel logistics results in concerns for using the traditional fossil fuel like diesel and crude oil as energy source ,other issues of environmental impact e.g. air pollution, acidification and material waste. This paper took a hybrid approach, Study the requirements of Utilizing associated gas in electrical power generation, select the suitable solution for power generation from associated gas and collect the all data required for analysis.

The world has been facing the COVID-19 pandemic since December 2019. Timely and efficient diagnosis of COVID-19 suspected patients plays a significant role in medical treatment. The deep transfer learning-based automated COVID-19 diagnosis on chest X-ray is required to counter the COVID-19 outbreak. This work proposes a real-time Internet of Things (IoT) framework for early diagnosis of suspected COVID-19 patients by using ensemble deep transfer learning. The proposed framework offers real-time communication and diagnosis of COVID-19 suspected cases. The proposed IoT framework ensembles four deep learning models such as InceptionResNetV2, ResNet152V2, VGG16, and DenseNet201. The medical sensors are utilized to obtain the chest X-ray modalities and diagnose the infection by using the deep ensemble model stored on the cloud server. The proposed deep ensemble model is compared with six well-known transfer learning models over the chest X-ray dataset. Comparative analysis revealed that the proposed model can help radiologists to efficiently and timely diagnose the COVID-19 suspected patients.

This paper presents the implementation of a fuzzy proportional integral derivative (FPID) control design to track the airway pressure during the mechanical ventilation process. A respiratory system is modeled as a combination of a blower-hose-patient system and a single compartmental lung system with nonlinear lung compliance. For comparison purposes, the classical PID controller is also designed and simulated on the same system. According to the proposed control strategy, the ventilator will provide airway flow that maintains the peak pressure below critical levels when there are unknown parameters of the patient’s hose leak and patient breathing effort. Results show that FPID is a better controller in the sense of quicker response, lower overshoot, and smaller tracking error. This provides valuable insight for the application of the proposed controller.

Today, there is a large increase in the demand for electricity. The transmission and distribution networks, however, cannot fulfill unbound demands due to the scarcity of resources. Power lines have losses which make the situation more unfavorable for maximum power transfer. Implementing a flexible AC transmission system (FACTS) is one of the best ways to reduce line losses. This paper proposes a FACTS-based method for minimizing the fault current in the system. Switchgear and protection equipment also perform better when this is done. Moreover, due to the reduced fault current of the switched system, a larger amount of power can be transmitted. Static synchronous series compensator (SSSC), static synchronous compensator (STATCOM), and unified power flow controller (UPFC) are evaluated in this case. With STATCOM and UPFC, fault currents are significantly reduced. Furthermore, STATCOM and UPFC can also reduce the fault currents in the power system in addition to voltage regulation and power flow control. A MATLAB/Simulink model is used to evaluate the model’s feasibility.

Recently, InGaN grown on semipolar and non-polar orientation has caused special attraction due to reduction in the built-in polarization field and increased confinement of high energy states compared to traditional polar c-plane orientation. However, any widespread-accepted report on output power and frequency response of the InGaN blue laser in non-c-plane orientation is readily unavailable. This work strives to address an exhaustive numerical investigation into the optoelectronic performance and frequency response of In0.17Ga0.83N/GaN quantum well laser in polar (0001), non-polar (101&macr, 0) and semipolar (101&macr, 2), (112&macr, 2) and (101&macr, 1) orientations by working out a 6 &times, 6 k.p Hamiltonian at the &Gamma, point using the tensor rotation technique. It is noticed that there is a considerable dependency of the piezoelectric field, energy band gap, peak optical gain, differential gain and output power on the modification in crystal orientation. Topmost optical gain of 4367 cm&minus, 1 is evaluated in the semipolar (112&macr, 2)-oriented laser system at an emission wavelength of 448 nm when the injection carrier density is 3.7 &times, 1018 cm&minus, 3. Highest lasing power and lowest threshold current are reported to be 4.08 mW and 1.45 mA in semipolar (112&macr, 2) crystal orientation. A state-space model is formed in order to achieve the frequency response which indicates the highest magnitude (dB) response in semipolar (112&macr, 2) crystal orientation.

The purpose of this study was to describe the ocular findings, structural ocular complications, and vision impairment in a cohort of Lassa fever survivors in Kenema, Sierra Leone. A retrospective, uncontrolled, cross-sectional study of 31 Lassa fever survivors (62 eyes) who underwent an ophthalmic evaluation in January 2018 at the Kenema Government Hospital in Kenema, Sierra Leone was performed. Data collection included demographic information, ocular/systemic symptoms, visual acuity (VA), and ophthalmic examination findings. Main outcome measures included anterior and posterior segment ophthalmic manifestations and level of VA impairment in Lassa fever survivors. Anterior segment findings included cataract (18%) and pterygium (2%), while posterior segment manifestations consisted of glaucoma (6%), preretinal hemorrhage (2%), and lattice degeneration (2%). Findings suggestive of prior sequelae of uveitis included chorioretinal scarring (5%), retinal fibrosis (3%), and vitreous opacity (2%). Visual acuity was normal/mildly impaired in 53 eyes (85%), moderately impaired in 6 eyes (10%), and 3 eyes (5%) were considered blind by the World Health Organization (WHO) criteria. Median VA was worse in Lassa fever survivors with ophthalmic disease findings (p

Using electronic coordinated control of governor and blade in the wind integrated hybrid power system, this study evaluated four proposed techniques for minimizing output fluctuations owing to high wind power penetration. Four cases were investigated for simulation analysis in this study. The power system frequency and energy generation were used as indexes to evaluate the best-proposed techniques. The control of all wind turbine blade angles was demonstrated using a constant and variable reference power generating technique. In terms of wind farm output power characteristics, grid frequency fluctuations, and wind farm energy levels, case 2 performed better than other suggested systems (cases 1, 3, and 4). Frequency deviations were kept to a minimum of ±0.2 Hz. The performance of the power system with higher wind power penetration was investigated using a numerical analysis employing a multi-machine power system model. The real wind speed data were recorded on Hokkaido Island, Japan.

In this article, a Quasi D-Shape dual core Photonic Crystal Fiber Surface Plasmon Resonance sensor is offered and numerically analyzed. The offered model is established comprising of circular air holes having an external sensing polishing layer coated with gold (Au) in order to ensure simple and straightforward design. The performance parameters are examined by means of modal analysis incorporated finite element method utilizing COMSOL multiphysics software. The sensor performance is analyzed with modifying the geometrical parameters like metal (Au) layer and pitch. It is observed; this model shows maximum amplitude sensitivity of 230 RIU−1 and wavelength sensitivity of 15,000 nm-RIU−1 incorporating amplitude interrogation method and wavelength interrogation method, respectively. The Figure of Merit is similarly considered and measured to 45 per RIU inbetween the refractive index ranging 1.42 RIU to 1.46 RIU. As a final point, a comparison has been given among the work explained in this paper with existing works.

The aim of this research is to identify the effects of the social factors on the resevidisim. This paper studied those social factors which directly have role on reoffending. The method is used in this research to present the results is charts with explanation. In the end this study has concluded some results which are: the social factors have a huge impact on commiting criminal behavior. Furthermore, the economical factors have an important role upon criminal behavior as well. Social measures have role in commiting crime.

In recent years, wind energy has been widely used as an alternative energy source as it is a clean energy with a low running cost. However, the high penetration of wind power (WP) in power networks has created major challenges due to their intermittency. In this study, an elitist multi-objective evolutionary algorithm called non-dominated sorting particle swarm optimization (NSPSO) is proposed to solve the dynamic economic emission dispatch (DEED) problem with WP. The proposed optimization technique referred to as NSPSO uses the non-dominated sorting principle to rank the non-dominated solutions. A crowding distance calculation is added at the end of all iterations of the algorithm. In this study, WP is represented by a chance-constraint which describes the probability that the power balance cannot be met. The uncertainty of WP is described by the Weibull distribution function. In this study, the chance constraint DEED problem is converted into a deterministic problem. Then, the NSPSO is applied to simultaneously minimize the total generation cost and emission of harmful gases. To proof the performance of the proposed method, the ten-unit and forty-unit systems&mdash, including wind farms&mdash, are used. Simulation results obtained by the NSPSO method are compared with other optimization techniques that were presented recently in the literature. Moreover, the impact of the penetration ratio of WP is investigated.

An analytical model has been developed to investigate the activation energy profile in Mg-doped p-AlxGa1−xN alloy for the entire range of Al composition. For any Al content, the calculated activation energy quantitatively shows a good agreement with experimental result which has also been confirmed by both Hydrogen atom model and effective Bohr radius model. Through this empirical analysis, a breakthrough is apparent for the hole concentration and sheet resistivity with particular Al concentration. It is found that the hole concentration is 30% in p-AlxGa1-xN. Moreover, the sheet resistivity is found to be

In the current study, a novel Zeonex based porous core photonic crystal fiber (PC-PCF) is presented for polarization-maintaining and dispersion flattened in the terahertz (THz) region. For minimizing the Effective Material Loss (EML), an array of three rectangular and six triangular air holes are surrounded by hexagonal-shaped cladding. Finite Element Method (FEM) is employed through Comsol V5.3a software to design and examine the essential features of the proposed porous core fiber which revealed that it has an extremely small EML of 0.04 cm−1 at 1.2 THz and has almost zero flattened dispersion of 0.8 ± 0.08 ps/THz/cm in 1.0–1.4 THz frequency spectrum. Moreover, the optimum designing parameters offer an extremely high value of birefringence (0.043 at 1.2 THz). Besides, other major features notably bending loss, effective area, and confinement loss are also found to be precise and relatively low. For effective, adaptable and fitting transmission characteristics, this type of design would lay the foundations for broadband THz radiation wide variety of usage in the THz regime.

The Maldives is an archipelago of 407,660 people according to population census of 2014, made up of 20 atolls, which has one of the highest prevalence of β-thalassemia worldwide. However, there is a dearth of studies related to β-thalassemia in the Maldives; therefore, in this study, we aimed to investigate the genetic epidemiology of β-thalassemia in Maldives. Blood samples were collected from 110,504 participants (1992–2015). Hemoglobin and RBC indices were measured on automated hematology analyzers. The quantitation of hemoglobin, HbA2, Hb F, and other abnormal Hb variants were assessed by HPLC. Molecular analysis was performed for the most common mutations in Southeast Asia for only 874 individuals either heterozygous or homozygous for these mutations using reverse dot blot hybridization. We screened 110,504 individuals for β-thalassemia between 1992 and 2015, which is ~ 30% of the entire population. The β-thalassemia carrier frequency was estimated to be 16.2%. Molecular diagnosis of 874 β-thalassemia carriers/major was performed for the most common seven mutations in Southeast Asia; of these, 139 patients were diagnosed as β-thalassemia major. This analysis showed that the most common mutations were IVS1 + 5G > C, (678; 77.6%), followed by the CD 30 (136; 15.6%). The least frequent mutation was FS8/9, (1, 0.001%), followed by IVS1 + 1G > T and CD15 (2; 0.2%). The frequency of β-thalassemia varies significantly among the 20 different atolls in Maldives. This study is expected to improve genetic counseling, creating awareness, enhance premarital screening, and customize the prevention and treatment strategies based on the needs of each atoll.

This paper presents the design approach of Generalized Dynamic Inversion (GDI) for angular position control of SRV02 rotary servo base system. In GDI, linear first order constraint differential equations are formulated based on the deviation function of angular position and its rate, and its inverse is calculated using Moore-Penrose Generalized Inverse to realize the control law. The singularity problem related to generalized inversion is solved by the inclusion of dynamic scaling factor that will guarantee the boundedness of the elements of the inverted matrix and stable tracking performance. Numerical simulations and real-time experiment are performed to evaluate the tracking performance and robustness capabilities of the proposed control law considering nominal and perturbed model dynamics. For comparative analysis, the results of GDI is compared with conventional PID control. Simulation and experimental results demonstrate better angular position tracking for the square-wave and sinusoidal waveforms, which reveals the superiority, and agility of GDI control over conventional PID.

BACKGROUND Acne vulgaris is a common chronic inflammatory skin disease involving pilosebaceous units. Adipokines are secreted by adipose tissue and function as signaling networks communicating it with different organs. They may have role in pathogenesis of acne vulgaris and the associated insulin resistance. Irisin, a hormone like myokine, is one of adipokines with anti-inflammatory, anti-oxidant, and anti-diabetic effects. AIMS We aimed at evaluation of serum irisin level in patients with acne vulgaris to assess its correlation with disease pathogenesis. PATIENTS AND METHODS Serum irisin level was measured by an ELISA technique in 60 acne vulgaris patients and 60 apparently healthy controls. Insulin resistance was calculated by Homeostasis Model Assessment of Insulin Resistance index. RESULTS Serum irisin level was significantly lower in acne vulgaris patients than control group (P

Background Knee osteoarthritis is a common and a disabling musculoskeletal disorder. Patients with knee osteoarthritis have activity limitations which are linked to the strength of the quadriceps muscle. Previous research reported that the relationship between quadriceps muscle strength and physical function is moderated by the level of knee joint frontal plane laxity. The purpose of the current study is to reexamine the moderation effect of the knee joint laxity as measured by stress radiographs on the relationship between quadriceps muscle strength and physical function. Methods One-hundred and sixty osteoarthritis patients participated in this cross-sectional study. Isometric quadriceps muscle strength was measured using an isokinetic dynamometer. Self-rated and performance-based physical function were measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function subscale and Get Up and Go test, respectively. Stress radiographs which were taken while applying varus and valgus loads to knee using the TELOS device. Knee joint laxity was determined by measuring the distance between joint surfaces on the medial and lateral sides. Hierarchical multiple regression models were constructed to study the moderation effect of laxity on the strength function relationship. Results Two regression models were constructed for self-rated and performance-based function. After controlling for demographics, strength contributed significantly in the models. The addition of laxity and laxity–strength interaction did not add significant contributions in the regression models. Conclusion Frontal plane knee joint laxity measured by stress radiographs does not moderate the relationship between quadriceps muscle strength and physical function in patients with osteoarthritis.

In the technology driven era, robot assisted surgery is gradually emerging as a revolutionized surgical procedure over traditional laparoscopic method. Despite the concerns about robotic surgery for minimally invasive surgical procedures, robotized surgical arms have been used in many hospitals. Certain surgical procedures require removal of a segment of an organ or body part like excision biopsy, linear thin layer of soft tissue, triangular mass, and tangential excision in burn management, where shaving-off at an angle of the tissue layer to be removed. For such minimally invasive procedures, we have designed a surgical arm governed by a rotary flexible joint. The surgical arm has a medical grade scalpel in its one end and the other end is connected to a D.C. servo motor. The motion of the surgical arm is controlled by the newly designed non-integer order controller. We have experimentally demonstrated the functioning of the surgical arm by ablating the tissue in-vitro. Our surgical robotic arm is cost effective, high precision and free from potential human errors.

The purposes of this study were first to examine the association between aging and both the magnitude and asymmetry in the femoral neck-shaft angle (NSA). The second purpose was to determine the effects of both the magnitude and NSA asymmetry on the performance of functional activities in healthy individuals. Fifty-one subjects participated in this study. The femoral NSA was measured on computed tomography scout images. The participants performed four performance tests. Four hierarchical regression models were constructed to explore the effect of each predictor on the outcomes. Aging was associated with NSA asymmetry, but not with the degree of NSA. Age contributed significantly to the variability of all functional performance tests except the 10-m walking speed. The degree of the NSA did not contribute to the prediction of the functional performance tests. However, asymmetry in the NSA added significantly to the prediction of all functional performance tests except the 10-m walking speed.

Wearable electronics require flexible supercapacitors with specially fabricated electrode materials, i.e., foldable and freestanding. Although activated carbon is the most used electrode’s active material for aqueous supercapacitors, it is a challenge to pack the particulates into flexible electrodes. Typically, polytetrafluoroethylene binder and polymeric flexible substrate are used, rendering a large amount of inactive-material. Here, we successfully fabricated multiwalled carbon nanotube/activated-carbon (MWCNT-AC) freestanding sheet via a scalable surface-engineered tape-casting technique to be used as a flexible electrode for aqueous supercapacitors. Instead of focusing on improving MWCNTs as active materials, the sheets act as a conducting matrix that binds together the activated-carbon particulates. MWCNT-AC has a specific capacitance of 135.17 Fg−1 (123.9 Fg−1 after 1000 cycles) at 1 Ag−1 from − 0.8 to 0.2 V vs. Hg/HgO (in three-electrode cell).

The presence of impurities within multiwalled carbon nanotubes (MWCNTs) have major, but as-yet-unrecognized, effects on the electrochemical behavior of MWCNTs in vanadium redox flow batteries. We show that MWCNTs constitute a high-surface-area, electrically conductive, inactive carbon matrix that acts as a bridge between and a support for carbonaceous impurities that are highly active toward the VO2+/VO2+ redox couple. We use freestanding sheets of MWCNTs, either purified and subsequently not modified with impurities (pure) or purified and subsequently contaminated with carbonaceous impurities (impure), as electrodes to eliminate the need for a substrate and thus undesired mixed kinetics. Electrodes fabricated with pure MWCNTs show low activities; attributed to relatively inactive basal sites. In contrast, impure electrodes show high activities due to the increased number of defects and edge sites resulting from the presence of the impurities. Functionalization of pure MWCNTs surface with oxygen-containing groups substantially improve the activity of the electrodes. However, functionalization is not as effective when carbonaceous impurities are present. The carbonaceous impurities form a continuous debris layer over the nanotube fibers, which reduces the effect of the oxidation treatment. Our results indicate that the impurity content of MWCNTs should be considered in studies of their activity and functionalization.

Double-gate (DG) metal---oxide---semiconductor field-effect transistors (MOSFETs) with GaN channel material are very promising for use in future high-performance low-power nanoscale device applications. In this work, GaN-based sub-10-nm DG-MOSFETs with different gate work function, $$\varPhi $$ź, were designed and their performance evaluated. Short-channel effects (SCEs) were significantly reduced by introduction of gates made of dual metals. Use of gold at the source side, having higher $$\varPhi $$ź ($$\varPhi _{\mathrm{Au}}=5.11\,\hbox {eV}$$źAu=5.11eV) compared with aluminum ($$\varPhi _{\mathrm{Al}}=4.53\,\hbox {eV}$$źAl=4.53eV), at the drain side enhanced the gate control over the channel and screened the effect of the drain on the channel. Dual-metal (DM) DG-MOSFETs showed better results in the nanoscale regime and were more robust to SCEs. Therefore, GaN-based sub-10-nm DM DG-MOSFETs are suitable candidates for use in future complementary metal---oxide---semiconductor (CMOS) technology.

Fractional order control schemes are being actively investigated for various systems. Fractional order concept is incorporated in integral (I), proportional integral (PI), proportional derivative (PD) or proportional integral derivative (PID) controller to investigate the performance of different state variables of the system. These techniques are often used for the purpose of technology transfer but very scanty research has so far been conducted using state space approach. The current investigation is initiated to observe the effect of fractional order controller using state space approach for the system's performance while tracking the position and regulating the speed of a linear servo cart system. Integer order controller based on proportional derivative (PD) approach is also shown for comparison. Simulation responses are presented and analyzed, in this investigation. The superiority of state space approach based fractional order controller is shown in the results. The paper contains a literature review on several control techniques used to control position and speed of a servo-cart system. An over view of mathematical modeling of servo cart system and a description of a proposed fractional controller is presented in this paper. A brief description of integer order control scheme is also presented. Simulated results are compared and discussed for both fractional order controller and integer order controller at the end of this paper.

In this study, hydroxyapatite (HAP) was synthesized by hydrothermal method. The structural analysis, thermal analysis and electrical characteristics of HAP sample have been investigated. The structural analysis was performed to determine the crystal structure and to observe the surface morphology of the sample. The thermal analysis was made from room temperature to 925 ˚C, to determine the mass loss according to temperature and phase transitions or decomposition in the sample and also TG-DTA analysis was done to determine the thermal stability. The compositional analysis was done by EDX. I-V analysis was made to calculate the electrical conductivity value of the sample and electrical conductivity of the sample was obtained to be 1.2x10-10 S/cm.

Enhancing the efficiency of membrane distillation (MD) is crucial for implementing this desalination technology on a large scale for freshwater production. Herein, an interesting opportunity of enhancing membrane distillation performance by applying an external electromagnetic field to the feed stream is demonstrated. It has been proven that electromagnetic fields can affect water evaporation rate, which is primarily related to the effect of the electromagnetic field on the hydrogen bonds of water clusters. However, as of yet, the enhancement in MD performance through the assistance of electromagnetic fields has not been previously recognized. Herein, it is demonstrated that the permeate flux of membrane distillation can be increased by up to 10% through exposing the saline feed water to an external electromagnetic field (EMF). It was found that the presence of divalent ions in the feed solution during the application of EMF resulted in a higher increase in permeate flux than when only NaCl was present. The electromagnetic treatment is non-destructive to current MD and thus can be easily adapted to large-scale water desalination processes.

The widespread usages of sensitive equipment such as computers, controllers and microelectronic devices have placed immense burden on the grid operators to deliver high quality electrical power to their customers. To achieve this end, the power quality disturbances (PQD) within the network need to be minimized. In this paper, a method to enhance the performance of the multiclass support vector machine (MSVM) classifier using the modified cuckoo search (MCS) is proposed. The wavelet packet transform is used to extract the crucial features from the PQD waveforms; these features are utilized as the input data to the classifier. In order to achieve high accuracy, robustness and speed, the MCS optimizes the number of selected features, as well as the penalty factor and slack variable of the MSVM. The proposed combinatorial algorithm (MCS-MSVM) is tested using 31 categories of PQD events; the hypothetical data for these events are generated by the IEEE 1159 Standard parametric equations. From simulation, the classification accuracy is recorded to be 100% under the no-noise condition, while at the signal-to-noise ratios (SNR) of 10, 20, 30 and 40 dB, the accuracies are 98.40, 98.54, 99.14 and 99.64%, respectively. Moreover, the comparative assessment concludes that the proposed method is superior to other heuristics-MSVM classification methods, namely the GA, PSO, differential evolution, harmony search and the conventional cuckoo search. The practical performance of the MCS-MSVM classifier is validated using real-time PQD data of a typical 11-kV underground distribution network, obtained from a particular electrical utility operator. For benchmarking, comparisons are made to 17 most recent PQD classification techniques published in literature. It is found that the proposed method exhibits the highest accuracies and the lowest computation times under ideal and noisy environments.

This paper elucidates the details of exciton localization dynamics in InGaN/GaN and GaN/AlInN quantum wells (QWs) using Monte Carlo simulation for a wide range of temperatures (10---300 K). We find that the phonon-induced variation of exciton lifetimes has remarkable effects on the photoluminescence (PL) peak position and the line-width. The red-shift of PL peak position at high temperature is clarified. The combined effects of phonon-induced radiative lifetime of excitons and the band-gap shrinkage at high temperature show the most reasonable agreement with the experimentally observed red-shift of the PL peak position. We have also quantitatively explained the temperature dependence of the W-shaped line-width in both InGaN/GaN and GaN/AlInN QWs. These results are highly significant to understand the emission properties of III-nitride QWs optoelectronic devices.

[Purpose] Literature has revealed age-related changes in body regional tissues in the form of reduced muscle size and increased adipose tissue. There is also a decline in the performance of physical function with aging. The aim of this study is to examine the partial and part correlations between physical performance and thigh tissue composition among elderly adults. [Subjects and Methods] Twenty-two elderly participants enrolled in this cross-sectional study. Mid-thigh CT images were used to determine the cross-sectional area of the muscular and adipose tissues. Principal component score of physical function was calculated from 5 performance based physical function tests using principal component analysis. Partial and part correlation statistics were used to explore the association between physical performance and tissue composition. [Results] There were significant, moderate negative partial and part associations between the principal component score and cross-sectional area of thigh muscles, quadriceps muscle and quadriceps normal density muscle. Significant, moderate positive partial and part correlations were found between intramuscular adipose tissue and the principal component score. [Conclusion] Elderly adults' performance of physical function is associated with regional tissue composition.

In this paper, a fractional order control law is proposed and implemented for the evaluation of trajectory tracking performance of a rotary flexible-joint system. A state feedback based fractional integral control scheme is used in this proposed method. In this scheme, state feedback is responsible for stabilizing the system. The compensator, in series with the fractional integrator leads to obtain a similar closed-loop transient response like Bode’s ideal transfer function. The effectiveness of the proposed controller in tracking and being robust against parameter uncertainties is demonstrated through simulation. In addition, to show the usefulness of the proposed control scheme, the fractional controller is compared to an integer state feedback control by simulation and through experimentation on the Quanser’s rotary flexible-joint system.

Iraq suffers from electricity shortages, through the local market and government institutions, has preliminary and applied information in the field of renewable energies, represented by solar energy, wind energy and bio-energy, at a simple level and small capacities, and in the near future it will rise to the levels of high energy stations. Note that the National Energy Strategy has set the percentage of renewable energy participation from total electric energy to reach 5%, about 2 Gigawatt by the year 2030. The plan includes several interval times, including the introduction of renewable energy in the agricultural sector to withdraw and pump water in drip irrigation systems, and the use of solar water heaters and heating systems and lighting systems operating with photovoltaic solar energy, as well as manufacturing all solar energy supplies and systems such as batteries, inverters, electric charger, solar heaters and solar panels, the effect of education and rationalization of consumption, increasing the efficiency of the use of electric energy, recycling waste to get rid of environmental pollution and producing biogas by Medium and large entrepreneurial systems in Iraqi cities. As well as the introduction of green building techniques in building homes, buildings and residential complexes to reduce electrical energy consumption with the introduction of solar-powered air conditioning systems. Reducing risks in renewable energy projects depends on several factors, including technology risks, monetary currency, natural resources, electrical grid risks, political risks, and the most dangerous are the risks resulting from terrorism and thefts at present in Iraq and requires an advanced and secure security system. Based on public datasets and reasonable assumptions, the provisional results obtained suggest the following; solar PV zones are located in the western region of Al-Anbar along the Jordanian Border. Despite the large capacities of these clusters, they are located at more than 300 km from Baghdad; wind zones are spread across the north-western area of Al-Anbar and south-eastern region, from Baghdad to Al-Basrah governorates.

This paper reviews and evaluates the hardware solutions to mitigate the effect of partial shading for grid-connected photovoltaic (PV) system. It encompasses both the module-level as well as the array-level approaches. The former enhances the energy yield by maximizing the power extraction capability of each individual module. Here, three methods, namely the micro inverter, the power optimizer and the energy recovery circuit are covered. On the other hand, the array-level mitigation—which includes the dynamic and static array reconfigurations optimize the arrangement of the modules to minimize the effect of partial shading on the energy yield. Besides updating the important aspects of the technologies, this paper delves into the economic viability of the solutions, as well as the challenges and future trend. In addition, it benchmarks the performance of the module-level solutions with the system with string inverter using Simulink. It is discovered that if the plant is highly shaded, the net energy gain of the micro-inverter and power optimizer is significant. On the other hand, if the shading is non-existent, employing these devices can be counterproductive (in terms of yield).