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51.
Kamoun WS Schmugge SJ Kraftchick JP Clemens MG Shin MC 《IEEE transactions on bio-medical engineering》2008,55(1):162-170
Intravital microscopy has been used to visualize the microcirculation by imaging fluorescent labeled red blood cells (RBCs). Traditionally, microcirculation has been modeled by computing the mean velocity of a few, randomly selected, manually tracked RBCs. However, this protocol is tedious, time consuming, and subjective with technician related bias. We present a new method for analyzing the microcirculation by modeling the RBC motion through automatic tracking. The tracking of RBCs is challenging as in each image, as many as 200 cells move through a complex network of vessels at a wide range of speeds while deforming in shape. To reliably detect RBCs traveling at a wide range of speeds, a window of temporal template matching is applied. Then, cells appearing in successive frames are corresponded based on the motion behavior constraints in terms of the direction, magnitude, and path. The performance evaluation against a ground truth indicates the detection accuracy up to 84% TP at 6% FP and a correspondence accuracy of 89%. We include an in-depth discussion on comparison of the microcirculation based on motion modeling from the proposed automated method against a mean velocity from manual analysis protocol in terms of precision, objectivity, and sensitivity. 相似文献
52.
Mohamad I. Elhadad Walid El‐Shafai El‐Sayed M. El‐Rabaie Mohammed Abd‐Elnaby Fathi E. Abd El‐Samie 《International Journal of Communication Systems》2020,33(6)
Guaranteeing a certain delay threshold for delay‐sensitive applications in long term evolution (LTE) cellular communication system is a very challenging mission. By implementing an optimal scheduling strategy, this mission will be achieved. In this article, a novel scheduler is introduced in order to meet a predefined level of service quality by guaranteeing a specific delay threshold for delay‐sensitive applications in LTE cellular systems. The proposed scheduler assigns the available resource blocks (RBs) to active user equipments (UEs) tacking into consideration several attributes. The expiration date of each packet, the channel quality, the average data rate previously achieved by each UE, and the number of dropped packets for each UE compared with the average number of packets totally dropped are all considered in the proposed scheduler working mechanism. Consequently, the proposed scheduling strategy reduces the number of packets dropped for multimedia applications, and at the same time maximizes the overall throughput of the network. Simulation results are provided to study and evaluate the performance of the proposed scheduling strategy. A comparative study is presented between the proposed strategy and the most recent scheduling techniques. The obtained results prove that the proposed scheduling strategy has considerably acceptable and appreciated results compared with the results of the state‐of‐the‐art scheduling techniques. 相似文献
53.
Rohit Samkria Mohammed Abd-Elnaby Rajesh Singh Anita Gehlot Mamoon Rashid Moustafa H. Aly Walid El-Shafai 《计算机、材料和连续体(英文)》2021,69(2):1709-1723
Fault detection of the photovoltaic (PV) grid is necessary to detect serious output power reduction to avoid PV modules’ damage. To identify the fault of the PV arrays, there is a necessity to implement an automatic system. In this IoT and LabVIEW-based automatic fault detection of 3 × 3 solar array, a PV system is proposed to control and monitor Internet connectivity remotely. Hardware component to automatically reconfigure the solar PV array from the series-parallel (SP) to the complete cross-linked array underneath partial shading conditions (PSC) is centered on the Atmega328 system to achieve maximum power. In the LabVIEW environment, an automated monitoring system is developed. The automatic monitoring system assesses the voltage drop losses present in the DC side of the PV generator and generates a decimal weighted value depending on the defective solar panels and transmits this value to the remote station through an RF modem, and provides an indicator of the faulty solar panel over the built-in Interface LabVIEW. The managing of this GUI indicator helps the monitoring system to generate a panel alert for damaged panels in the PV system. Node MCU in the receiver section enables transmission of the fault status of PV arrays via Internet connectivity. The IoT-based Blynk app is employed for visualizing the fault status of the 3 × 3 PV array. The dashboard of Blynk visualizes every array with the status. 相似文献
54.
Fatma M. El-Ghamry Walid El-Shafai Mahmouad I. Abdalla Ghada M. El-Banby Abeer D. Algarni Moawad I. Dessouky Adel S. Elfishawy Fathi E. Abd El-Samie Naglaa F. Soliman 《计算机、材料和连续体(英文)》2022,71(3):4457-4487
Recently, ground-penetrating radar (GPR) has been extended as a well-known area to investigate the subsurface objects. However, its output has a low resolution, and it needs more processing for more interpretation. This paper presents two algorithms for landmine detection from GPR images. The first algorithm depends on a multi-scale technique. A Gaussian kernel with a particular scale is convolved with the image, and after that, two gradients are estimated; horizontal and vertical gradients. Then, histogram and cumulative histogram are estimated for the overall gradient image. The bin values on the cumulative histogram are used for discrimination between images with and without landmines. Moreover, a neural classifier is used to classify images with cumulative histograms as feature vectors. The second algorithm is based on scale-space analysis with the number of speeded-up robust feature (SURF) points as the key parameter for classification. In addition, this paper presents a framework for size reduction of GPR images based on decimation for efficient storage. The further classification steps can be performed on images after interpolation. The sensitivity of classification accuracy to the interpolation process is studied in detail. 相似文献
55.
Bargach Walid Zidane Mustapha Benyoussef Abdelilah Ez-Zahraouy Hamid Laamara Rachid Ahl 《Journal of Superconductivity and Novel Magnetism》2022,35(2):331-338
Journal of Superconductivity and Novel Magnetism - Electronic and magnetic properties of CdS-based, doped by various transition metal elements (Ti, V, Cr, Mn, Fe, Co or Ni), dilute magnetic... 相似文献
56.
Recent advances in communication and networking technologies are leading to a plethora of novel wireless services that range from unmanned aerial vehicle(UAV)communication to smart cognitive networks and massive Internet of Things(IoT)systems.Enabling these emerging applications over the fifth generation(5G)of wireless cellular systems requires meeting numerous challenges pertaining to spectrum sharing and management.In fact,most 5G applications will be highly reliant on intelligent spectrum management techniques,which should adapt to dynamic network environments while also guaranteeing high reliability and high quality-of-experience(QoE). 相似文献
57.
Khaleel Mershad Qutaibah M. Malluhi Mourad Ouzzani Mingjie Tang Michael Gribskov Walid G. Aref Deo Prakash 《Distributed and Parallel Databases》2018,36(1):121-151
Data curation activities in collaborative databases mandate that collaborators interact until they converge and agree on the content of their data. In a previous work, we presented a cloud-based collaborative database system that promotes and enables collaboration and data curation scenarios. Our system classifies different versions of a data item to either pending, approved, or rejected. The approval or rejection of a certain version is done by the database Principle Investigators (or PIs) based on its value. Our system also allows collaborators to view the status of each version and help PIs take decisions by providing feedback based on their experiments and/or opinions. Most importantly, our system provided mechanisms for history tracking of different versions to trace the modifications and approval/rejection done by both collaborators and PIs on different versions of a data item. We labeled our system as Update-Pending-Approval model (or UPA). In this paper, we describe a high level SQL query interface language for PIs and collaborators to interact with the UPA framework. We define a set of UPA keywords that are used as a part of the history tracking mechanism to select specific versions of a data item, and a set of UPA options that select specific versions based on possible future decisions of PIs. We implemented our query interface mechanism on top of Apache Phoenix, taking into consideration that the UPA system was implemented on top of Apache HBase. We test the performance of the UPA query language by executing several queries that contain different complexity levels and discuss their results. 相似文献
58.
Anatase nanocrystalline titania coatings were produced on cotton fabrics from alkoxide solutions using a low-temperature sol–gel process under ambient pressure. Titania coatings of the anatase form were obtained via a classical hydrolysis and condensation reaction of titanium isopropoxide that was followed by a boiling water treatment for 180 min. Spectroscopic and microscopic characterizations of the titania thin films showed that the anatase form is predominant throughout the film after the boiling water treatment and that the size of the grains is about 20 nm. The titania coating on fabrics is a promising process for use as an antibacterial photocatalyst in the textile industry. 相似文献
59.
Walid A. Daoud John H. Xin Xiaoming Tao 《Journal of the American Ceramic Society》2004,87(9):1782-1784
We successfully prepared transparent and durable superhydrophobic silica-coating films on cotton substrates at low temperatures. The coatings were produced via cohydrolysis and polycondensation of a hexadecyltrimethoxysilane (HDTMS), tetraethoxyorthosilcate (TEOS), and 3-glycidyloxypropyltrimethoxysilane (GPTMS) mixture. The hydrophobic properties of the nanocomposite coatings were determined using contact-angle and water-gain measurements. The water contact angle for the coated substrates was 141°, whereas, before coating, the contact angle was 0° because of the superhydrophilic nature of cotton. The nanocomposite coating has new applications in daily used materials, especially those with low heat resistance, such as textiles and plastics, and as an environmentally friendly water-repellent substitute for fluorine compounds. 相似文献
60.