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The purpose of this paper is to analyze wind climate parameters and performance functions, on the basis of two years of data, and reliability of Pakistan’s first wind farm located at Jhimpir, Sindh.

The methodology covers assessment of wind climate parameters including wind variation at different hub heights, wind shear and diurnal wind shear. In addition, a performance assessment of a wind farm on the basis of technical and real availability, capacity factor and failure rate of mechanical and electrical components has been conducted. The Weibull method has been used for reliability analysis. The maintenance model is proposed for improving the performance. Last is about annual energy volume lost and of financial constraints’ assessment.

The monthly mean wind variation at heights of 80, 60 and 30 m was found to be 8, 6.9 and 5.9 m/s, respectively. The monthly mean wind shear coefficient was found to be 0.2419. The performance assessment of the wind farm includes technical and real availability, and the capacity factor was found to be 97, 90 and 35.5 per cent, respectively. The failure rate found in the first and second year was 8 and 14 per cent, respectively. Reliability decreased from the first year to the second year, i.e. 0.89 to 0.71 per cent. The components’ failure frequency rose to 57.2 per cent in the second year. The lost energy production due to electrical and mechanical failures was 27.241 GWh in two years that cost Pakistani Rs. 329.8m.

The results of the assessment show that a wind farm needs drastic maintenance strategies to maximize the its performance.

To control one of the joints during the actual movement of the hydraulically driven quadruped robot, all the other joints in the leg need to be locked. Once the joints are unlocked, there is a coupling effect among the joints. Therefore, during the normal exercise of the robot, the movement of each joint is affected by the coupling of other joints. This brings great difficulties to the coordinated motion control of the multi-joints of the robot. Therefore, it is necessary to reduce the influence of the coupling of the hydraulically driven quadruped robot.

To solve the coupling problem with the joints of the hydraulic quadruped robot, based on the principle of mechanism dynamics and hydraulic control, the dynamic mathematical model of the single leg mechanism of the hydraulic quadruped robot is established. On this basis, the coupling dynamics model of the two joints of the thigh and the calf is derived. On the basis of the multivariable decoupling theory, a neural network (NN) model reference decoupling controller is designed.

The simulation and prototype experiment are carried out between the thigh joint and the calf joint of the hydraulic quadruped robot, and the results show that the proposed NN model reference decoupling control method is effective, and this method can reduce the cross-coupling between the thigh and the calf and improve the dynamic characteristics of the single joint of the leg.

The proposed method provides technical support for the mechanical–hydraulic cross-coupling among the joints of the hydraulic quadruped robot, achieving coordinated movement of multiple joints of the robot and promoting the performance and automation level of the hydraulic quadruped robot.

On the basis of the theory of multivariable decoupling, a new decoupling control method is proposed, in which the mechanical–hydraulic coupling is taken as the coupling behavior of the hydraulic foot robot. The method reduces the influence of coupling of system, improves the control precision, realizes the coordinated movement among multiple joints and promotes the popularization and use of the hydraulically driven quadruped robot.

This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and verifies its decoupling effect..

The machine–hydraulic cross-linking coupling is studied as the coupling behavior of the hydraulically driven quadruped robot, and the mechanical dynamics coupling force of the robot system is controlled as the disturbance force of the hydraulic system through the Jacobian matrix transformation. According to the principle of multivariable decoupling, a prediction-based neural network model reference decoupling control method is proposed; each module of the control algorithm is designed one by one, and the stability of the system is analyzed by the Lyapunov stability theorem.

The simulation and experimental research on the robot joint decoupling control method is carried out, and the prediction-based neural network model reference decoupling control method is compared with the decoupling control method without any decoupling control method. The results show that taking the coupling effect experiment between the hip joint and knee joint as an example, after using the predictive neural network model reference decoupling control method, the phase lag of the hip joint response line was reduced from 20.3° to 14.8°, the amplitude attenuation was reduced from 1.82% to 0.21%, the maximum error of the knee joint coupling line was reduced from 0.67 mm to 0.16 mm and the coupling effect between the hip joint and knee joint was reduced from 1.9% to 0.48%, achieving good decoupling.

The prediction-based neural network model reference decoupling control method proposed in this paper can use the neural network model to predict the next output of the system according to the input and output. Finally, the weights of the neural network are corrected online according to the predicted output and the given reference output, so that the optimization index of the neural network decoupling controller is extremely small, and the purpose of decoupling control is achieved.

The purpose of this paper is to present the power noise characteristics of a multilayer printed circuit board (PCB) in which discrete capacitors have been embedded.

Embedded technology has been implemented on a multilayer PCB to enhance the performance and functionality and to decrease the power noise. Decoupling capacitors were directly positioned on the inner power planes of a board, which resulted in low‐loop inductance through the minimized length of the interconnection from the chips to the PCB's power delivery network.

A low‐noise PCB was successfully designed and fabricated using an embedding process for the discrete decoupling capacitors. It was demonstrated that such an approach offers lower interconnection inductance and quiet noise performance, including highly efficient propagation noise suppression at wideband frequencies.

Most conventional simulation techniques offer expectations for the signal characteristics on the time domain to minimize bit error rates in application systems. Further development work will focus on the integrated simulation models including the equivalent circuits for the transmission line and power noise effects to improve the accuracy of the signal performance.

This paper presents a new approach for improving generating and propagating noise performance through the use of an embedded decoupling capacitor design methodology.

Laying the acoustic decoupling material on the surface of underwater structures is an effective noise reduction technology. The underwater sound radiation experiment of finite stiffened double cylindrical shell with separate‐sound and decoupled tile is carried out with the aim of finding out the most effective laying condition.

The segmentation power function interpolation method and vertex extreme value envelope continuation method are introduced into basic theory of empirical mode decomposition (EMD). The original measured sound pressure signals are decomposed to intrinsic mode function (IMF) group through EMD, and the high‐frequency components are filtered out. Because the mechanical noise of submarine is mainly at low frequency, the IMFs in low frequency are researched through power spectrum analysis. The noise reduction effects of different separate‐sound and decoupled tile laying conditions are compared.

The sound pressure signal components' amplitudes, periods and phases are obtained through EMD. The test data show that the double cylindrical shell entirely covered with separate‐sound and decoupled tile is the most effective laying condition in noise reduction.

With reference to the case study, this is believed to be the first application of the EMD in sound radiation time‐frequency characteristics of double cylindrical shell. The evaluation of separate‐sound and decoupled tile laying conditions is of great importance in engineering applications.

The purpose of this paper is to develop, apply and validate a mesh-free graph theory–based approach for rapid thermal modeling of the directed energy deposition (DED) additive manufacturing (AM) process.

In this study, the authors develop a novel mesh-free graph theory–based approach to predict the thermal history of the DED process. Subsequently, the authors validated the graph theory predicted temperature trends using experimental temperature data for DED of titanium alloy parts (Ti-6Al-4V). Temperature trends were tracked by embedding thermocouples in the substrate. The DED process was simulated using the graph theory approach, and the thermal history predictions were validated based on the data from the thermocouples.

The temperature trends predicted by the graph theory approach have mean absolute percentage error of approximately 11% and root mean square error of 23°C when compared to the experimental data. Moreover, the graph theory simulation was obtained within 4 min using desktop computing resources, which is less than the build time of 25 min. By comparison, a finite element–based model required 136 min to converge to similar level of error.

This study uses data from fixed thermocouples when printing thin-wall DED parts. In the future, the authors will incorporate infrared thermal camera data from large parts.

The DED process is particularly valuable for near-net shape manufacturing, repair and remanufacturing applications. However, DED parts are often afflicted with flaws, such as cracking and distortion. In DED, flaw formation is largely governed by the intensity and spatial distribution of heat in the part during the process, often referred to as the thermal history. Accordingly, fast and accurate thermal models to predict the thermal history are necessary to understand and preclude flaw formation.

This paper presents a new mesh-free computational thermal modeling approach based on graph theory (network science) and applies it to DED. The approach eschews the tedious and computationally demanding meshing aspect of finite element modeling and allows rapid simulation of the thermal history in additive manufacturing. Although the graph theory has been applied to thermal modeling of laser powder bed fusion (LPBF), there are distinct phenomenological differences between DED and LPBF that necessitate substantial modifications to the graph theory approach.

Precision active vibration isolation system (AVIS) is crucial for the mechanical processing equipment in the field of precision manufacturing. Working reliability and efficiency of the system directly influence operating condition of the equipment and the quality of work pieces.

A complete structure of the AVIS includes two parts: the excitation part and the passive vibration isolation system (PVIS). The excitation part consists of voice coil motors (VCMs). In this paper, the working process of AVIS is studied particularly via linear simplification on the decoupling model and the mechanical dynamic equations to solve the vibration problem, and they are validated by the experiments.

According to dynamic analysis and experiment on an AVIS on different reference points, the VCMs are used as actuators in the AVIS to excite the PVIS, and the performance characteristics of the whole AVIS is well reflected by the amplitude–frequency curves, the bode diagrams and the power spectral density curves.

This study has provided a way for obtaining the inner structure and working condition of the AVIS, which are essential to better control of the AVIS and to further study it in precision manufacturing application.

The paper aims to present a new mechanical scheme for a leg to be included in legged vehicles that simplifies the control actuations along the stride.

The scheme includes three four‐bar links grouped in two mechanisms. The first one decouples the vertical and horizontal foot movements. The second one produces a constant horizontal foot velocity when the corresponding motor is given a constant speed. A hybrid robot with wheels at the end of the hind legs has been simulated and constructed to validate the leg performance.

The gait control requires only five commands for the electronic cards to control the leg. Decoupling vertical and horizontal movements allows a more adequate selection of actuators, a reduction of energy consumption, and higher load capacity and robot velocity. Additional mechanical benefits, such as improved robustness and lower inertia, are obtained. The hind legs can also be articulated, allowing the robot to overcome an obstacle and to climb up and down stairs.

A hybrid robot offers greater stability with respect to a legged robot. This way the lateral movement is not a concern, and therefore it has not been tested yet during the walking cycle.

This new scheme obtains a quasi‐Cartesian behaviour for the foot movement that drastically simplifies the control of the walking cycle. Although the decoupling between movements has already been obtained in previous configurations, these follow a pantograph structure and suffer from blocking problems when they are subject to lateral forces. These schemes were suitable for crab‐like gaits. The proposed leg moves according to a mammal‐like gait.

Prior research suggests that consumers can engage in moral decoupling by separating their judgments of morality from their judgments of performance. Hence, they might rationalize the benefits of unethical behavior without condoning the behavior itself. This paper aims to study how a discrete positive emotion, such as authentic pride, can mitigate moral decoupling.

Using three experimental studies, this research investigates and tests the underlying mechanism driving authentic pride, its effects and its key moderator. The results are analyzed using ANOVAs, regression-based serial mediation and moderated mediation analyses.

The results show that authentic pride decreases consumer acceptance of unethical behavior across different contexts, including purchase intentions for unethically manufactured products (Study 1), evaluations of the corporate social responsibility activities of a tobacco company (Study 2) and acceptance of questionable consumer behavior in daily situations (Study 3).

This research explores attitudes and behavioral intentions as dependent variables. It would thus be of interest for future research to examine a behavioral measure.

Given the potential problems of moral decoupling among consumers, marketers can devise effective strategies to reduce this problem using authentic pride appeals.

This research demonstrates how authentic pride can decrease consumer acceptance of unethical behavior. More importantly, this research enriches our understanding of the underlying mechanism driving the influence of authentic pride such that it increases the belief in a just world, which in turn lowers moral decoupling (a serial mediation).

The purpose of this paper is to develop an automatic control system for mechanical ventilation therapy based on the open lung concept (OLC) using artificial intelligence. In addition, mean arterial blood pressure (MAP) is stabilized by means of a decoupling controller with automated noradrenaline (NA) dosage to ensure adequate systemic perfusion during ventilation therapy for patients with acute respiratory distress syndrome (ARDS).

The aim is to develop an automatic control system for mechanical ventilation therapy based on the OLC using artificial intelligence. In addition, MAP is stabilized by means of a decoupling controller with automated NA dosage to ensure adequate systemic perfusion during ventilation therapy for patients with ARDS.

This innovative closed-loop mechanical ventilation system leads to a significant improvement in oxygenation, regulates end-tidal carbon dioxide for appropriate gas exchange and stabilizes MAP to guarantee proper systemic perfusion during the ventilation therapy.

Currently, this automatic ventilation system based on the OLC can only be applied in animal trials; for clinical use, such a system generally requires a mechanical ventilator and sensors with medical approval for humans.

For implementation of a closed-loop ventilation system, reliable signals from the sensors are a prerequisite for successful application.

The experiment with porcine dynamics demonstrates the feasibility and usefulness of this automatic closed-loop ventilation therapy, with hemodynamic control for severe ARDS. Moreover, this pilot study validated a new algorithm for implementation of the OLC, whereby all control objectives are fulfilled during the ventilation therapy with adequate hemodynamic control of patients with ARDS.