Design and reliability assessment of control systems for a nuclear-based hydrogen production plant with copper–chlorine thermochemical cycle

The thermochemical Copper–Chlorine (Cu–Cl) cycle is an emerging new method of nuclear-based hydrogen production. In the process, water is decomposed into hydrogen and oxygen through several physical and chemical processes. In this paper, a Distributed Control System (DCS) is designed for the thermochemical Cu–Cl cycle. The architecture and the communication networks of the DCS are discussed. Reliability of the DCS is assessed using fault trees. In the assessment, the impact of the malfunction of the actuators, sensors, controllers and communication networks on the overall system reliability is investigated. This provides key information for the selection of control system components, and determination of their inspection frequency and maintenance strategy. The hydrogen reactor unit, which is one of the major components in the thermochemical Cu–Cl cycle, is used to demonstrate the detailed design and analysis.     

A new modified differential evolution algorithm scheme-based linear frequency modulation radar signal de-noising

The main intention of this study was to investigate the development of a new optimization technique based on the differential evolution (DE) algorithm, for the purpose of linear frequency modulation radar signal de-noising. As the standard DE algorithm is a fixed length optimizer, it is not suitable for solving signal de-noising problems that call for variability. A modified crossover scheme called rand-length crossover was designed to fit the proposed variable-length DE, and the new DE algorithm is referred to as the random variable-length crossover differential evolution (rvlx-DE) algorithm. The measurement results demonstrate a highly efficient capability for target detection in terms of frequency response and peak forming that was isolated from noise distortion. The modified method showed significant improvements in performance over traditional de-noising techniques.     

Comparative lyophilized platelet-rich plasma wafer and powder for wound-healing enhancement: formulation,in vitro and in vivo studies

Platelet-rich plasma (PRP) accelerates wound healing, as it is an excellent source of growth factors. PRP was separated from whole human blood by centrifugation. PRP powder and wafers were prepared by lyophilization, with the wafers prepared using sodium carboxymethylcellulose (Na CMC). The PRP wafers showed porous structures, as indicated by scanning electron microscopy (SEM) images, and the ability of the wafer to absorb exudates and thus promote wound healing was tested with the hydration capacity test. The platelet count was tested and indicated that the presence of PRP in the wafers had no effect on the platelet count. An antimicrobial activity test was carried out, showing that PRP had antibacterial activity against Gram-negative bacteria. Compared with lyophilized PRP powder and PRP-free wafers, PRP wafers showed the highest percent of wound size reduction on induced wounds in rats. Histopathological examination of rat skin showed that the PRP wafers achieved the shortest healing time, followed by the lyophilized PRP powder and finally the PRP-free wafers. The present study revealed that PRP can be formulated as a wafer, which is a promising pharmaceutical delivery system that can be used for enhanced wound-healing activity and improved the ease of application compared to lyophilized PRP powder.     

The performance of transistor fed monopoles in active antennas

The performance of radiating elements in the form of monopoles and driven by transistors is examined theoretically and experimentally. A single element comprising a printed monopole over a ground plane and fed at its terminals by a microwave transistor is shown to have superior frequency characteristics compared to the passive element. Using a two-element array configuration, it is verified that the mutual impedance values are suppressed. The improved individual characteristics of the active elements together with their mutual behavior combine to produce a significantly improved frequency performance of the array. The results presented suggest that the transistorized array principle offers a means both of maintaining directivity of a transmitter, and discriminating against interfering sources by a receiver, over a greater frequency band.     

Analysis of containment structures for randomly arriving transient loads

Hydrodynamic loads such as those due to safety relief valve discharges and a postulated accidental loss of coolant are some of the major loads on boiling water reactor (RWR) containments. Structural analysis of containments for these highly transient loads can be more efficiently carried out if the response transfer function approach is used. The formulation of such an approach is developed for axisymmetric containment structures. The load parameters, e.g. the maximum intensity, arrival time and predominant frequency may be randomly defined. To obtain the design response, repeated analyses for various sets of parameter values may be required. In such cases the transfer function approach as presented here is computationally very efficient. The formulation to obtain the mean and standard deviation of response for uniformly distributed load arrival time is also provided and the numerical results for a typical BWR containment are given.     

Target tracking in infrared imagery using weighted composite reference function-based decision fusion.

In this paper, we propose a novel decision fusion algorithm for target tracking in forward-looking infrared image sequences recorded from an airborne platform. An important part of this study is identifying the failure modes in this type of imagery. Our strategy is to prevent these failure modes from developing into tracking failures. The results furnished by competing ego-motion compensation and tracking algorithms are evaluated based on their similarity to a target model constructed using the weighted composite reference function.     

A novel secure solution of using mixed reality in data transmission for bowel and jaw surgical telepresence: enhanced rivest cipher RC6 block cipher

Security threats are crucial challenges that deter Mixed reality (MR) communication in medical telepresence. This research aims to improve the security by reducing the chances of types of various attacks occurring during the real-time data transmission in surgical telepresence as well as reduce the time of the cryptographic algorithm and keep the quality of the media used. The proposed model consists of an enhanced RC6 algorithm in combination. Dynamic keys are generated from the RC6 algorithm mixed with RC4 to create dynamic S-box and permutation table, preventing various known attacks during the real-time data transmission. For every next session, a new key is created, avoiding possible reuse of the same key from the attacker. The results obtained from our proposed system are showing better performance compared to the state of art. The resistance to the tested attacks is measured throughout the entropy, Pick to Signal Noise Ratio (PSNR) is decreased for the encrypted image than the state of art, structural similarity index (SSIM) closer to zero. The execution time of the algorithm is decreased for an average of 20%. The proposed system is focusing on preventing the brute force attack occurred during the surgical telepresence data transmission. The paper proposes a framework that enhances the security related to data transmission during surgeries with acceptable performance.

     

Groundwater Exploration and Assessment in Rural Communities of Yobe State, Northern Nigeria

The provision of adequate water supply and sanitation to the rapidly growing urban populations is increasingly becoming a problem for governments throughout the world. The continuing expansion of the numbers of people in cities who need water and sanitation services form a continuous pressure to either invest in additional production capacity or to stretch the available supplies to serve more people. Due to rapid increase in population growth in the Yobe State north of Nigeria, there is a shortage in the water supply to Damaturu city the capital of the state and surrounding villages. At the present the total water supply is about 10,000 m³/day abstracted form the shallow alluvial groundwater aquifer using 29 production wells. Due to the expected increase in water demand and the limited potentiality of shallow aquifer system, other deep aquifers were explored and investigated to evaluate their potentiality for future water demand. Vertical Electrical Sounding Method was used for the geophysical survey of the study area. Groundwater flow model was developed and calibrated against the historical information. Three wellfields were designed to provide Damaturu city and surrounding villages with the required water. The calibrated model has been used to evaluate the aquifer potentiality and the effect of future withdrawals on the deep aquifer system. It was found that the aquifer system within the study area consists of two main layers. The upper layer is the Chad formation comprises an alluvial sand and gravel with intercalation of thin sility clay layers. The second layer is Keri-Keri formation consists of sandstone formation which is not explored before. During this study the Kerri-Kerri aquifer system was investigated as an alternative source for groundwater for future demand. The study presents an integrated groundwater resources management strategy for present and future water supply for rural communities.     

A novel augmented reality for hidden organs visualisation in surgery: enhanced super-pixel with sub sampling and variance adaptive algorithm

In recent years, Augmented Reality (AR) has gained more attention as an effective tool in medical surgeries. The potentials of using AR in the medical field can change conventional medical procedures. However, the technology still facing fundamental challenges, especially hidden organs, for example, the organs behind the bowel and liver. The surgeries in these areas lack accuracy in the visualization of the soft tissues behind the bowel and liver like the uterus and gall bladder. This research aims to improve the accuracy of visualisation and the processing time of the augmented video. The proposed system consists of an enhanced super-pixel algorithm with variance weight adaptation and subsampling method. The simulation studies show significant improvements in visualization accuracy and a reduction in processing time. The results show reduced visualisation error by 0.23 mm. It provides better accuracy of the video in terms of visualization error from 1.58?~?1.83 mm to 1.35?~?1.60 mm, and the processing time decreases from 50?~?58 ms/frames to 40?~?48 ms/frames. The proposed system \ focused on the pixel refinement for the 3d reconstruction of the soft tissue, which helps solve the issue of visualising the bowel and liver in an augmented video.