scholarly journals Icing Condition Predictions Using FBGS

Sensors ◽  
2021 ◽  
Vol 21 (18) ◽  
pp. 6053
Author(s):  
Miguel González del Val ◽  
Julio Mora Nogués ◽  
Paloma García Gallego ◽  
Malte Frövel
Keyword(s):  
Accretion Rate ◽  
Detection System ◽  
Theoretical Calculations ◽  
Liquid Water Content ◽  
Balance Model ◽  
Good Precision ◽  
Ice Accretion ◽  
Test Results ◽  
Optic Fibers ◽  
Near Future

Icing is a hazard which is important for the aerospace industry and which has grown over the last few years. Developing sensors that can detect the existence not only of standard icing conditions with typically small droplet size, but also of Supercooled Large Droplet (SLD) conditions is one of the most important aims in order to minimize icing hazards in the near future. In the present paper a study of the Fiber Bragg Grating Sensors’ (FBGSs) performance as a flight icing detection system that predicts the conditions of an icing cloud is carried out. The test matrix was performed in the INTA Icing Wind Tunnel (IWT) with several icing conditions including SLD. Two optic fibers with 16 FBGS in total were integrated in the lower and upper surface of an airfoil to measure the temperature all over the chord. The results are compared with a Messinger heat and mass balance model and the measurements of the FBGS are used to predict the Liquid Water Content (LWC) and Ice Accretion Rate (IAR). Finally, the results are evaluated and a sensor assessment is made. A good correlation was observed between theoretical calculations and test results obtained with the FBGS in the IWT tests. FBGS proved to detect the beginning and end of ice accretion, LWC and IAR quickly and with good precision.

scholarly journals Ice-Accretion Test Results for Three Large-Scale Swept-Wing Models in the NASA Icing Research Tunnel

2016 ◽  
Author(s):  
Andy P. Broeren ◽  
Mark G. Potapczuk ◽  
Sam Lee ◽  
Adam M. Malone ◽  
Bernard P. Paul ◽  
...  
Keyword(s):  
Large Scale ◽  
Ice Accretion ◽  
Test Results ◽  
Swept Wing

The Analytical and Experimental Research of In-Vessel Corium Retention in CPR1000

2010 ◽  
Author(s):  
Xing Chen ◽  
Shishun Zhang ◽  
Jiming Lin ◽  
Huiyong Zhang
Keyword(s):  
Experimental Research ◽  
Success Probability ◽  
Outer Wall ◽  
Test Results ◽  
Pressurized Water Reactor ◽  
Structural Failure ◽  
Pressurized Water ◽  
Thermal Failure ◽  
Near Future ◽  
Preliminary Phase

The analytical and experiment research of In-Vessel Corium Retention (IVR) in the Chinese Pressurized-water Reactor 1000 MWe (CPR1000) are introduced. The IVR research consists of preliminary phase and detailed phase. The analysis of thermal failure, structural failure and penetration failure of Reactor Pressure Vessel (RPV) and the experimental research of External Reactor Vessel Cooling (ERVC) are performed at preliminary phase. Analysis results show that the RPV failure is the dominated by thermal failure mode and the probability of the thermal failure is very low. Test results show that the IVR success probability for CPR1000 is about 99% if the Critical Heat Flux (CHF) of CPR1000 is the same as that of AP600. Further works, including the ERVC enhancement design, the CHF test of the RPV outer wall and the recalculation of the IVR success probability for CPR1000, will be performed at detailed phase in the near future.

Development of a real-time machine vision system for functional textile fabric defect detection using a deep YOLOv4 model

2021 ◽  
pp. 004051752110342
Author(s):  
Sifundvolesihle Dlamini ◽  
Chih-Yuan Kao ◽  
Shun-Lian Su ◽  
Chung-Feng Jeffrey Kuo
Keyword(s):  
Machine Vision ◽  
Real Time ◽  
Defect Detection ◽  
Data Augmentation ◽  
Detection System ◽  
Vision System ◽  
Good Precision ◽  
Machine Vision System ◽  
Time Machine ◽  
Textile Fabric

We introduce a real-time machine vision system we developed with the aim of detecting defects in functional textile fabrics with good precision at relatively fast detection speeds to assist in textile industry quality control. The system consists of image acquisition hardware and image processing software. The software we developed uses data preprocessing techniques to break down raw images to smaller suitable sizes. Filtering is employed to denoise and enhance some features. To generalize and multiply the data to create robustness, we use data augmentation, which is followed by labeling where the defects in the images are labeled and tagged. Lastly, we utilize YOLOv4 for localization where the system is trained with weights of a pretrained model. Our software is deployed with the hardware that we designed to implement the detection system. The designed system shows strong performance in defect detection with precision of [Formula: see text], and recall and [Formula: see text] scores of [Formula: see text] and [Formula: see text], respectively. The detection speed is relatively fast at [Formula: see text] fps with a prediction speed of [Formula: see text] ms. Our system can automatically locate functional textile fabric defects with high confidence in real time.

Helicopter flight characteristics in icing conditions

2012 ◽  
Vol 116 (1183) ◽  
pp. 963-979 ◽  
Author(s):  
Yihua Cao ◽  
Guozhi Li ◽  
R. A. Hess
Keyword(s):  
State Space Model ◽  
Liquid Water Content ◽  
Atmospheric Temperature ◽  
Ice Accretion ◽  
Handling Qualities ◽  
Helicopter Flight ◽  
Different Types ◽  
Ice Shedding ◽  
Temperature Liquid ◽  
Further Development

Abstract A method to predict the effects of rotor icing on the flight characteristics of a UH-60A helicopter is presented. By considering both natural ice shedding and different types of ice accretion due to local temperature variations on the blade surface, an improved rotor icing model was developed. Next, the effects of icing on rotor force, torque and flapping were incorporated in a nonlinear helicopter dynamic model. Based upon icing design envelopes in cumuliform clouds, trim and stability characteristics were studied. Further development of the helicopter state-space model allowed control and handling qualities characteristics to be investigated with variation of the three icing-related cloud variables (atmospheric temperature, liquid water content, and median volumetric diameter). Results indicated that this method of evaluating rotorcraft icing is both feasible and useful.

scholarly journals Implementasi Algoritma You Only Look Once (YOLO) untuk Deteksi Korban Bencana Alam

2021 ◽  
Vol 8 (4) ◽  
pp. 787
Author(s):  
Moechammad Sarosa ◽  
Nailul Muna
Keyword(s):  
Image Processing ◽  
Natural Disasters ◽  
Natural Disaster ◽  
Test Data ◽  
Detection System ◽  
Training Data ◽  
Test Results ◽  
Disaster Victim ◽  
Rapid Evacuation

<p class="Abstrak">Bencana alam merupakan suatu peristiwa yang dapat menyebabkan kerusakan dan menciptakan kekacuan. Bangunan yang runtuh dapat menyebabkan cidera dan kematian pada korban. Lokasi dan waktu kejadian bencana alam yang tidak dapat diprediksi oleh manusia berpotensi memakan korban yang tidak sedikit. Oleh karena itu, untuk mengurangi korban yang banyak, setelah kejadian bencana alam, pertama yang harus dilakukan yaitu menemukan dan menyelamatkan korban yang terjebak. Penanganan evakuasi yang cepat harus dilakukan tim SAR untuk membantu korban. Namun pada kenyataannya, tim SAR mengalami kendala selama proses evakuasi korban. Mulai dari sulitnya medan yang dijangkau hingga terbatasnya peralatan yang dibutuhkan. Pada penelitian ini sistem diimplementasikan untuk deteksi korban bencana alam yang bertujuan untuk membantu mengembangkan peralatan tim SAR untuk menemukan korban bencana alam yang berbasis pengolahan citra. Algoritma yang digunakan untuk mendeteksi ada atau tidaknya korban pada gambar adalah <em>You Only Look Once</em> (YOLO). Terdapat dua macam algoritma YOLO yang diimplementasikan pada sistem yaitu YOLOv3 dan YOLOv3 Tiny. Dari hasil pengujian yang telah dilakukan didapatkan <em>F1 Score</em> mencapai 95.3% saat menggunakan YOLOv3 dengan menggunakan 100 data latih dan 100 data uji.</p><p class="Abstrak"> </p><p class="Abstrak"><strong><em>Abstract</em></strong></p><p class="Abstrak"> </p><p class="Abstract"><em>Natural disasters are events that can cause damage and create havoc. Buildings that collapse and can cause injury and death to victims. Humans can not predict the location and timing of natural disasters. After the natural disaster, the first thing to do is find and save trapped victims. The handling of rapid evacuation must be done by the SAR team to help victims to reduce the amount of loss due to natural disasters. But in reality, the process of evacuating victims of natural disasters is still a lot of obstacles experienced by the SAR team. It was starting from the difficulty of the terrain that is reached to the limited equipment needed. In this study, a natural disaster victim detection system was designed using image processing that aims to help find victims in difficult or vulnerable locations when directly reached by humans. In this study, a detection system for victims of natural disasters was implemented which aims to help develop equipment for the SAR team to find victims of natural disasters based on image processing. The algorithm used is You Only Look Once (YOLO). In this study, two types of YOLO algorithms were compared, namely YOLOv3 and YOLOv3 Tiny. From the test results that have been obtained, the F1 Score reaches 95.3% when using YOLOv3 with 100 training data and 100 test data.</em></p>

scholarly journals Flame Spraying of Aluminum Coatings Reinforced with Particles of Carbonaceous Materials as an Alternative for Laser Cladding Technologies

Materials ◽  
2019 ◽  
Vol 12 (21) ◽  
pp. 3467 ◽  
Author(s):  
Artur Czupryński
Keyword(s):  
Laser Cladding ◽  
Carbon Materials ◽  
High Strength ◽  
Preliminary Test ◽  
Flame Spraying ◽  
Test Results ◽  
Carbonaceous Materials ◽  
Aluminum Coatings ◽  
Cylinder Liners ◽  
Near Future

The article presents results of the preliminary research of mechanical properties of flame-sprayed aluminum coatings reinforced with carbon materials made on the construction steel S235J0 substrate. For reinforcement the following carbon materials were used: carbon nanotubes Nanocyl NC 7000 (0.5 wt.% and 1 wt.%) and carburite (0.5 wt.%). The properties evaluation was made using metallographic macroscope and microscope, chemical composition, microhardness, abrasion and erosion resistance studies. The obtained results were compared with aluminum powder coatings (EN AW 1000 series). It was proved that the flame spraying of aluminum coatings reinforced with particles of carbonaceous materials can be an effective alternative for laser cladding technology. The preliminary test results will be successively extended by further experiments to contribute in the near future to develop innovative technologies, that can be implemented in the automotive industry for production of components with high strength, wear resistance, good thermal conductivity and low density, such as brake shoes, cylinder liners, piston rings and gears.

scholarly journals Effects of skin heat conduction on aircraft icing process

2020 ◽  
pp. 095441002097257
Author(s):  
Xiaobin Shen ◽  
Yu Zeng ◽  
Guiping Lin ◽  
Zuodong Mu ◽  
Dongsheng Wen
Keyword(s):  
Heat Conduction ◽  
Temperature Distribution ◽  
Skin Temperature ◽  
Accretion Rate ◽  
Skin Surface ◽  
Ice Thickness ◽  
Ice Accretion ◽  
Aircraft Icing ◽  
Outer Skin ◽  
Lateral Heat

During the aircraft icing process caused by super-cooled droplet impingement, the surface temperature and heat flux distributions of the skin would vary due to the solid substrate heat conduction. An unsteady thermodynamic model of the phase transition was established with a time-implicit solution algorithm, in which the solid heat conduction and the water freezing were analyzed simultaneously. The icing process on a rectangular skin segment was numerically simulated, and the variations of skin temperature distribution, thicknesses of ice layer and water film were obtained. Results show that the presented model could predict the icing process more accurately, and is not sensitive to the selection of time step. The latent heat released by water freezing affects the skin temperature, which in turn changes the icing characteristics. The skin temperature distribution would be affected notably by the boundary condition of the inner skin surface, the lateral heat conduction and thermal property of the skin. It was found that the ice accretion rate of the case that the inner surface boundary is in natural convection at ambient temperature is much smaller than that with constant ambient temperature there; due to the skin lateral heat conduction, the outer skin surface temperature increases first and then decreases with uneven distribution, leading to an unsteady ice accretion rate and uneven ice thickness distribution; a smaller heat conductivity would lead to a more uneven temperature distribution and a lower ice accretion rate in most regions, but the maximum ice thickness could be larger than that of higher heat conductivity skin. Therefore, in order to predict the aircraft icing phenomenon more accurately, it is necessary to consider the solid heat conduction and the boundary conditions of the skin substrate, instead of applying a simple boundary condition of adiabatic or a fixed temperature for the outer skin surface.

The fifth force: An enigma in this Universe

2019 ◽  
Vol 34 (09) ◽  
pp. 1950056 ◽  
Author(s):  
Koijam Manihar Singh ◽  
Kangujam Priyokumar Singh
Keyword(s):  
Theoretical Calculations ◽  
Point Of View ◽  
Theoretical Point ◽  
Experimental Proof ◽  
Fifth Force ◽  
Theory Of Everything ◽  
Discovery Science ◽  
Near Future ◽  
The Universe ◽  
High Hope

In an attempt to explain some of the unknown phenomena of nature, including dark energy and dark matter, we explore the possibility of the existence of a fifth fundamental force of nature as also cited by some researchers. With the inclusion of such a force in the system, some of the vague things can be explained and there is high hope of its importance in building up a “theory of everything”. With this intention, we investigate some manifestations of the fifth force which stand from theoretical calculations or from theoretical point of view, though till now there is less experimental proof. However, the theoretical results obtained indicate the existence of a fifth force which will lead to the completion in defining the laws of physics and nature. With this discovery, science may be able to explain the whole complexity of the Universe in near future.

Study of Remote Elevator Monitoring Fault Detection System

2012 ◽  
Vol 499 ◽  
pp. 459-463 ◽  
Author(s):  
Jian Liu ◽  
Dong Sheng Fan ◽  
Yue Wu ◽  
Guo Jiang Fu ◽  
Mei Ju Liu
Keyword(s):  
Monitoring System ◽  
Detection System ◽  
System Efficiency ◽  
Test Results ◽  
Resource Center ◽  
Control Scheme ◽  
Interface Function ◽  
Important Means ◽  
Embedded Terminal ◽  
Main Thread

Remote Elevator Monitoring (REM) is an important means to ensure elevator secure, reliable working. In this paper, an elevator remote monitoring control scheme is proposed based on multi-threaded technology. Due to all threads in the multi-threaded technology may visit the same overall situation object and the shared resource, center system communicates with embedded terminal is achieved by the method. The remote elevator monitoring system has been designed based on the multi-threaded technology; the main thread interface function is realized by monitor center software, other management operations are also executed in the system. The test results show that the multi-threaded technology applies to the monitoring system, which enhances the system efficiency and security.

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