Integrated influential factors (iifs) model of internal stakeholders as an adaptive control system to curb projects completion delay in Yemen

The construction industry usually encounters lingering problems particular to time delay which is a major concern that affects project completion time globally. Influential factors causing delays in construction projects completion differ among countries, due to differing prevailing conditions that exert an influence on construction project delivery. In Yemen and other developing countries, many projects experience extensive delays by exceeding their initial completion time thereby leading to several reported effects which among others include: cost overrun; litigation; arbitration; failure; and abandonment. In order to mitigate these effects, a prevailing approach that is reported to being implemented is enhancing the collaboration of stakeholders in construction project delivery. This study seeks to propose an Integrated Influential Factor (IIF) model of internal stakeholders with a view to prevent delay in construction project delivery. A questionnaire survey was carried out among owners, consultants and contractors. A total of 301 questionnaires were collected of which 283 responses were found valid. Analysis of Moment Structures Equation Modelling (AMOS-SEM) model was developed based on 7 groups related to internal stakeholders of construction projects which are: consultant influential factors; contractor influential factors; owner influential factors; sub-contractor influential factors; designer influential factors; supplier influential factors; and labour influential factors. The findings from the IIFs model indicate that out of these 7 groups studied, while contractor, owner, subcontractor, designer and supplier have significant effect on delay, consultant and labour were not supported. Based on the path co-efficient value however, the most significant category is ‘contractor influential factors’. The implication of this research, it could enhance the integration of internal stakeholders and expect to be drastically eliminate the fear relative to project time delay of construction project delivery

Development of Monitoring System Based on Internet of Things (IoT) for Freshwater Prawn Farming

Aqua-farming or water farming is an aquatic counterpart to agriculture or ground farming. It is one of methods to make out foods or commercial product. With the current incompetent aqua-farming activities such as labour energy consumption to monitor the water quality and to change the water in the tank in schedule so that this project is important to tackle down the problems stated. This project aimed to reduce the incompetency of water quality monitoring process and the water changing process by developing a vertical freshwater prawn tank to reduce space with an automated water changing and IoT based monitoring system. The autonomous system implemented with solenoid valve and waterpump will recycle the water from the prawn tanks with the clean water from the reservoir tank. The monitoring system employs ultrasonic sensor and waterproof temperature sensor that will monitor the water level in the prawn tanks and the temperature of the water respectively that will be visualized in the Thingspeak Channel regularly. This project will be implemented as a prototype with an IoT technology for the freshwater prawn farming activity using low-cost embedded devices like Arduino Mega2560, ESP8266 Wi-Fi module and the RTC module. The value from the sensors’ reading will be visualized in the Thingspeak Channel displa

Two-Element MIMO Crack Finger Microstrip Antenna for Hand-Held Devices

in this paper, we studied the effect of mutual coupling between MIMO antennas and a method is proposed to reduce it between 2-element micro-strip MIMO antenna systems for handheld devices. To reduce mutual coupling between the MIMO antenna element a separate ground plane is designed and the two elements are positioned on the edges of the 2-element MIMO antenna system. A novel idea defined in order to reduce mutual coupling between the closely spaced micro-strip patch elements is adding finger shapes at the edge of each patch antenna to design a new crack finger micro-strip the fingers generate capacitance in between which improved the matching between the patch and the Micro-strip transmission line as well as the mutual coupling reduced from -25 dB to -40 dB. The simulation results showed that the 2-element MIMO system covered the frequency of 2.4 GHz, and the gain and directivity are 6.149 dB and 4.399All the simulations were carried out in CST Microwave Studio

Twin Delayed Deep Deterministic Policy Gradient-Based Target Tracking for Unmanned Aerial Vehicle with Achievement Rewarding and Multistage Training

Target tracking using an unmanned aerial vehicle (UAV) is a challenging robotic problem. It requires handling a high level of nonlinearity and dynamics. Model-free control effectively handles the uncertain nature of the problem, and reinforcement learning (RL)-based approaches are a good candidate for solving this problem. In this article, the Twin Delayed Deep Deterministic Policy Gradient Algorithm (TD3), as recent and composite architecture of RL, was explored as a tracking agent for the UAV-based target tracking problem. Several improvements on the original TD3 were also performed. First, the proportional-differential controller was used to boost the exploration of the TD3 in training. Second, a novel reward formulation for the UAV-based target tracking enabled a careful combination of the various dynamic variables in the reward functions. This was accomplished by incorporating two exponential functions to limit the effect of velocity and acceleration to prevent the deformation in the policy function approximation. In addition, the concept of multistage training based on the dynamic variables was proposed as an opposing concept to one-stage combinatory training. Third, an enhancement of the rewarding function by including piecewise decomposition was used to enable more stable learning behaviour of the policy and move out from the linear reward to the achievement formula. The training was conducted based on fixed target tracking followed by moving target tracking. The flight testing was conducted based on three types of target trajectories: fixed, square, and blinking. The multistage training achieved the best performance with both exponential and achievement rewarding for the fixed trained agent with the fixed and square moving target and for the combined agent with both exponential and achievement rewarding for a fixed trained agent in the case of a blinking target. With respect to the traditional proportional differential controller, the maximum error reduction rate is 86%. The developed achievement rewarding and the multistage training opens the door to various applications of RL in target tracking

Frequency reconfigurable substrate integrated waveguide (SIW) cavity F-shaped slot antenna

This paper shows a frequency reconfigurable SIW F-slot suitable for some applications. Configurability is accomplished by embeddings PIN diode switches in the 'F' slot. The proposed antenna is equipped for exchanging between working band of 3.172 GHz to 3.606 GHz in four different narrow bands and it underpins the cognitive system for LTE2300, WiMAX and WLAN. For each case reflection coefficient is ascertained, it keeps up less than -10 dB all through the resonating frequency in all instances of diode switching. The electromagnetic energy is kept inside the cavity because of the frame of a metallic vias. In all instances of diodes exchanging, it's uncovered a decent effectiveness of efficiency and gain

The desirability of Integrated Influential Factors (IIFs) model of internal stakeholder as a panacea to project completion delay in Yemen

In Yemen and other developing countries, many construction projects experience extensive delays by exceeding their initial completion time thereby leading to several reported effects which among others include: cost overrun; litigation; arbitration; failure; and abandonment. Although variability in prevailing conditions warrants influential factors causing such delays to differ among countries, an oft-cited approach implemented to mitigate these effects is enhancing the collaboration of stakeholders in construction project delivery. While this approach is overwhelmingly applauded by researchers, there however exist scant studies focusing on how effective project internal stakeholder integration can potentially impact prompt construction project delivery particularly in developing countries. This study as such, seeks to propose an Integrated Influential Factor (IIF) model of internal stakeholders with a view to reduce delay in construction project delivery. Data was collected from 301 respondents based on the influential factors divided into 7 categories of internal stakeholders. Findings from analysed results (using IBM SPSS Statistics 23.0 and IBM SPSS AMOS SEM Version 23) were used to develop the Integrated Influential Factors (IIF) Model of Internal Stakeholder in Yemen Construction Industry. The proposed model was validated through construction industries expert opinion which inform that sincere and concerted effort towards effective management of the studied factors could not only stem down their adverse effect on project completion delay but equally enhance construction project implementation if the model is tenaciously implemented

Twin delayed deep deterministic policy gradient-based target tracking for unmanned aerial vehicle with achievement rewarding and multistage training

Target tracking using an unmanned aerial vehicle (UAV) is a challenging robotic problem. It requires handling a high level of nonlinearity and dynamics. Model-free control effectively handles the uncertain nature of the problem, and reinforcement learning (RL)-based approaches are a good candidate for solving this problem. In this article, the Twin Delayed Deep Deterministic Policy Gradient Algorithm (TD3), as recent and composite architecture of RL, was explored as a tracking agent for the UAV-based target tracking problem. Several improvements on the original TD3 were also performed. First, the proportional�differential controller was used to boost the exploration of the TD3 in training. Second, a novel reward formulation for the UAV-based target tracking enabled a careful combination of the various dynamic variables in the reward functions. This was accomplished by incorporating two exponential functions to limit the effect of velocity and acceleration to prevent the deformation in the policy function approximation. In addition, the concept of multistage training based on the dynamic variables was proposed as an opposing concept to one-stage combinatory training. Third, an enhancement of the rewarding function by including piecewise decomposition was used to enable more stable learning behaviour of the policy and move out from the linear reward to the achievement formula. The training was conducted based on fixed target tracking followed by moving target tracking. The flight testing was conducted based on three types of target trajectories: fixed, square, and blinking. The multistage training achieved the best performance with both exponential and achievement rewarding for the fixed trained agent with the fixed and square moving target and for the combined agent with both exponential and achievement rewarding for a fixed trained agent in the case of a blinking target. With respect to the traditional proportional differential controller, the maximum error reduction rate is 86%. The developed achievement rewarding and the multistage training opens the door to various applications of RL in target tracking

Frequency reconfigurable substrate integrated waveguide (SIW) cavity F-shaped slot antenna

This paper shows a frequency reconfigurable SIW F-slot suitable for some applications. Configurability is accomplished by embeddings PIN diode switches in the 'F' slot. The proposed antenna is equipped for exchanging between working band of 3.172 GHz to 3.606 GHz in four different narrow bands and it underpins the cognitive system for LTE2300, WiMAX and WLAN. For each case reflection coefficient is ascertained, it keeps up less than -10 dB all through the resonating frequency in all instances of diode switching. The electromagnetic energy is kept inside the cavity because of the frame of a metallic vias. In all instances of diodes exchanging, it's uncovered a decent effectiveness of efficiency and gain

Integrated influential factors of internal stakeholder that negatively affecting project successful completion in Yemen

Development construction projects in Yemen are encountering a huge delays in time, cost invade, surrendered and disappointment. Because of an emotional movement in the limit and volume of the Yemeni development part in the course of the most recent decade, the need of a deliberate investigation of the reasons that adversely influencing negatively the project successful completion and building up an unmistakable comprehension among the stakeholder experts is profoundly urgent. The fundamental objective of this study is to recognize and rank the causes that contrarily influencing the project successful completion in Yemen. Utilizing a chose set of 55 qualities, this exploration initially distinguished the key elements affecting project completion in Yemen development industry. A survey has framed the premise of this examination and dispersed to proprietor, advisor and temporary worker. The outcome covers that the 10 major delay factors including money cash flow and financial difficulties faced by contractors, conflict between owners and other parties, delay in progress payment by owner, poor project management, slow decision from owner, escalation of prices of materials, lack of contractor experience, design errors made by designers, shortages of materials and poor site management and supervision. These findings are expected to be significant contributions to Yemen construction industry in controlling the time and cost overruns in construction. The effect of (IIF) is negatively influences to project successful completion regarding to time overrun, cost overrun, negatively affect to satisfaction of the stakeholder, negatively affect to technical specification and negatively affecting to fulfillment all meeting all the project objectives/requirements. These findings are required to be noteworthy commitments to Yemen development industry in controlling the time and cost invades in development

Design and Analysis of Different Optical Attocells Deployment Models for Indoor Visible Light Communication System

Visible light communication (VLC) is a promising candidate that is expected to revolutionize indoor environment communications performance and fulfill fifth generation and beyond (5GB) technologies requirements. It offers high and free bandwidth, electromagnetic interference immunity, low-cost front end and low power consumption. Also, VLC has dual functions that could be utilized in both illumination and communication concurrently. The number of optical attocells (OAs) and their deployment in the room represent the main issue that should be taken into consideration in designing an optimal VLC system. In this paper, we have introduced a new model of five OAs in the typical room. In addition to an investigation of various optical attocells (OAs) deployment models, in which a multi-variable evaluation was performed in terms of received power, illumination, SNR and RMS delay spread in order to determine the optimal OAs model. Also, various modulation schemes performances were investigated which included NRZ-OOK, BPSK, and QPSK in order to improve the BER performance. Results indicated that BPSK modulation had superior BER performance when compared with all OAs models. Further, a comprehensive results analysis and comparison of all proposed models was conducted over various parameters, in which our new proposed OAs model achieved an optimal performance in comparison with the other models