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2021 ◽  
pp. 65-80
Author(s):  
Diana Paola Merchán Vargas ◽  
Helis Navarro Báez ◽  
Jaime Guillermo Barrero Pérez ◽  
Jeyson Arley Castillo Bohórquez

Skin cancer is one of the most common diseases in the world population. Usually, the diagnosis requires the acquisition of dermatoscopic images. Both biopsy and histopathology have been used in advanced stages. Its early detection is very important to increase patient life quality and life expectancy. In Colombia, the lack of qualified professionals and medical instruments difficulties this task. The automatic classification is a huge challenge, due to ample variety and morphology in skin lesions. Nowadays, Deep Learning reaches elevated accuracy levels in image classification tasks and is set to become a reliable solution for medical image classification. In this research, used these DNN advantages to build a convolutional neural network (CNN) trained with open source databases to the classification of skin lesions benign and malignant. After the training process, we develop an embedded system with raspberry Pi 3 B+ with a generic camera and implemented the CNN described in Python coded-based. For the benign and malignant classification, the prototype reached an accuracy level of 91.06% in the F1 score and a recall of 91.98%.


2021 ◽  
Author(s):  
Muhammad Arsalan ◽  
Jarl André Fellinghaug

Abstract Downhole power harvesting is an enabling technology for a wide range of future production systems and applications, including self-powered downhole monitoring, downhole robotics, and wireless intelligent completions. This paper presents the field experience of an innovative energy harvesting system that was successfully deployed and tested in the harsh downhole conditions of an oil producer. There is a critical need for robust and reliable downhole power generation and storage technologies to push the boundaries of downhole sensing and control. This paper provides an analysis of available ambient energy sources in the downhole environment, and various energy harvesting techniques that can be employed to provide a reliable solution. Advantages and limitations of conventional technique like turbine are compared to advanced energy harvesting technologies. The power requirements and technical challenges related to different downhole applications have also been addressed. The field experience of the novel flow-based energy harvesting system are presented, including the details of both the lab and field prototype design, deployment and testing.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Sapna Juneja ◽  
Abhinav Juneja ◽  
Gaurav Dhiman ◽  
Shashank Jain ◽  
Anu Dhankhar ◽  
...  

Hand gesture recognition is one of the most sought technologies in the field of machine learning and computer vision. There has been an unprecedented demand for applications through which one can detect the hand signs for deaf people and people who use sign language to communicate, thereby detecting hand signs and correspondingly predicting the next word or recommending the word that may be most appropriate, followed by producing the word that the deaf people and people who use sign language to communicate want to say. This article presents an approach to develop such a system by that we can determine the most appropriate character from the sign that is being shown by the user or the person to the system. To enable pattern recognition, various machine learning techniques have been explored and we have used the CNN networks as a reliable solution in our context. The creation of such a system involves several convolution layers through which features have been captured layer by layer. The gathered features from the image are further used for training the model. The trained model efficiently predicts the most appropriate character in response to the sign exposed to the model. Thereafter, the predicted character is used to predict further words from it according to the recommendation system used in this case. The proposed system attains a prediction accuracy of 91.07%.


2021 ◽  
Author(s):  
Peter Levison Mwansa ◽  
Esha Narendra Varma ◽  
Victor Jose Aguilar ◽  
Alexander Amorocho ◽  
Daniel McPherson ◽  
...  

Abstract Inability to effectively isolate depleted aquifer formations due to severe losses during cementation leads to accelerated corrosion of the production casing. Per current practice, a top job is performed from surface to fill the annulus with cement, but with limited success in a severe losses’ scenario. The objective is to improve zonal isolation by applying V0 rated multiple stage cementation technology with inner string thus enhancing well integrity during the life cycle of the well. A metal expandable annular sealing system was selected as a reliable isolation mechanism for effective cementation behind aquifers due to its ability to provide high expansion in potentially washed-out wellbores and the feature of long multi-element sealing systems with built in redundancy. The inner string operated stage cementing system provides a reliable solution to selectively and accurately place cement above the metal expandable packer whilst maintaining V0 casing integrity once closed. Additionally, the unique combination of technologies provides a cost-effective life of well solution compared to current stage cementing methodologies. Following successful execution of three trial jobs, the multi-stage cement using V0 rated tools and an inner string was compared to similar jobs done per current cementing practices. Analysis involved reviewing the cement bond column coverage and quality (CBL) with offset wells. Cement bond log results showed that this technique enhanced the cement column quality behind the 9 5/8" casing across the aquifer zones with moderate to good cement for the most part. Contaminated cement was observed just below the previous casing shoe and this could be addressed by adding another stage tool just above the previous casing shoe. Overall results show improved cement column quality for this section when compared to conventional jobs with similar conditions and is recommended for future use in severe to total losses scenario. In a situation where losses are seen at the previous casing shoe, a three-stage job is recommended. Other benefits include: Security and confidence in gas tight sealing capability and mechanical integrity Precise and conclusive operation for open, close and lock with no risk of accidental lock Ability to squeeze cement below the metal expandable packer No reduction in pressure rating regardless of OH ID and full bore ID of casing No post operation drill out required of the stage tools V0 stage cementing tools with inner string and metal expandable annular sealing system are not available on Oil & Gas market as a single tool. Therefore, this combined technology application of solutions from different technology providers to access a dedicated solution is totally novel and creates an opportunity for future applications across the industry.


2021 ◽  
Author(s):  
AHMET ULUSLU

Abstract Here, the selection of the design parameters of the bowtie patch antenna (BPA) for 5G applications is presented as a multidimensional, multi-purpose design optimization problem. The operating frequency of the proposed antenna is 28 GHz, which is the standard for millimeter waveband and 5G technologies. In order to overcome this difficult design optimization, a new, fast and powerful optimization algorithm was used by modified the non-dominant sorting genetic algorithm (NSGA)-III and optimal characterization of the microwave antenna design was obtained. It is assumed that the optimal characterization gives the best solution for the determined cost function, among the possible solutions within the specified range. The superiority of the proposed method has been proven by comparing it with similar types of algorithm. The antennas in the results found have good performance operating at 28 GHz, with a return loss of up to –49 dB, a gain of around 1.96 dB, good directivity, and the radiation pattern of the proposed antenna has a good match over the required frequency. Therefore, the proposed design can be used in 5G devices. As a whole, the proposed design optimization process is an efficient, fast and reliable solution for all antenna design problems.


2021 ◽  
pp. 159101992110632
Author(s):  
Philippe Gailloud

The course of the vertebral artery from its subclavian artery origin up to its termination at the vertebrobasilar junction is divided into four segments (V1–V4). This segmentation, based on schemes that have evolved since the late nineteenth century, should be a consistent and reproducible anatomical concept. However, the current literature offers conflicting definitions of that scheme, not infrequently within a single article or monograph. The principal inconsistency found in modern publications concerns the termination of the V2 segment, which is either set at the C2 or C1 transverse foramen depending on the scheme considered. Consequently, the portion of the vertebral artery extending between C2 and C1—a frequent site of pathological involvement—either belongs to the V2 or V3 segment. This discrepancy can affect the validity of studies evaluating the diagnosis and management of vertebral artery disorders. A V3 segment extending from the transverse foramen of C2 to the posterior atlanto-occipital membrane and subdivided into vertical, horizontal, and oblique subsegments—a pattern suggested by Barbieri in 1867 and adopted in some modern publications—would provide a simple, precise, and reliable solution without significantly altering the widely accepted division of the vertebral artery into four segments (V1–V4).


2021 ◽  
Author(s):  
Hala El-Khozondar ◽  
Fady El-batta ◽  
Rifa EL-Khozondar ◽  
Mansour Alramlawi

Abstract This work is motivated by the need to overcome the electricity crises in Gaza that is initiated in Gaza due to political reasons. In addition, it is related to current situation in the world in particular the spread of COVID-19. Building quarantine centers is one of the most important means used in combating the Corona epidemic, but connecting these centers to the electricity distribution network at the appropriate time is not always possible and increases the burden on the local utility company. This paper proposed a Hybrid off-grid Energy System (HES) to effectively energies the quarantine centers economically and environmentally. To achieve this aim, the load profile of the quarantine center is estimated, the system components are modeled and the system design is optimized. In addition, the developed approach was tested using a real case study considering realistic input data. HOMER-pro program is used to simulate and optimize the system design. The results revealed the potential of the HES to provide environment-friendly, cost-effective, and affordable electricity for the studied quarantine center, as compared to only diesel generators system. For the considered case study, it is found that the PV-Wind-Diesel hybrid power system is able to cover the connected load with the lowest cost in comparison to other possible HES structures. It also environmentally friendly as it has the least harmful emissions. Finally, it is proved that the developed approach gives a reasonable solution to the decision-makers to find a fast, economic and reliable solution to energies the quarantine centers.


Religions ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1049
Author(s):  
Małgorzata Szcześniak ◽  
Adam Falewicz ◽  
Zdzisław Kroplewski ◽  
Urszula Myszak ◽  
Hanna Borkowska ◽  
...  

Divine engagement applies to a positive relationship with God in which people feel that God is close to them and answers their prayers. Divine disengagement pertains to an unsteady connection and a sense of God’s absence. Although several questionnaires consider the concerns of the human experience of prayer, only one deals precisely with the subject of the human perception of divine engagement and disengagement in response to one’s prayer. The main goals of the present research were to: (1) determine the latent structure of the Brief Measure of Perceived Divine Engagement and Disengagement in Response to Prayer (PDED) in a sample set; (2) test whether the factor structure indicated by EFA matches the data and provides an equivalent goodness-of-fit index to Exline’s model; and (3) confirm that perceived divine engagement and disengagement are correlated with religious meaning, gratitude to God, and dimensions of religious centrality. The results show that the proposed two-factor structure of the eight-item version of the PDED is a suitable and reliable solution of the original PDED (Study 1). Confirmatory Factor Analysis (CFA) revealed a good fit of the data to the model in both the second and third studies. Both dimensions of the PDED correlated significantly with all of the subscales of the RMS, GGQ–6, and CRS–15. The Polish version of the PDED demonstrated very good psychometric properties.


2021 ◽  
Vol 11 (22) ◽  
pp. 10890
Author(s):  
Octavian Narcis Ionescu ◽  
Ileana Cernica ◽  
Elena Manea ◽  
Catalin Parvulescu ◽  
Alin Istrate ◽  
...  

There have been large developments in the unmanned aerial vehicles (UAV) industry over the last decade. Although UAV development was mainly for military related use in the beginning and despite there being fear surrounding the release of this technology to the open market for quite a long time, nowadays, there are a variety of applications where UAVs are used extensively, such as in agriculture, infrastructure inspection and monitoring, mobile retranslation relays for communications, etc. One of the weaknesses of electrically propelled UAVs is flight autonomy; there is often a difficult trade-of between the weight of the payload, batteries, and surface to be surveyed that is necessary to determine. There have been many attempts to use photovoltaic cells to increase the flight time for UAVs; however, a reliable solution has not yet been developed. The present paper presents improvements that have been conducted to extend the autonomy of electrically derived UAVs: instead of gluing photovoltaic cells on the wings, the new approach embeds the solar cells into the wing structure as well as develops a new wing that is significantly lighter to compensate for the weight added by the photovoltaic cells. It was demonstrated that by using this approach, a 33% increase in the flight time can be achieved with only one modified wing in a prototype vehicle.


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