A Photorealistic Predictive Display

2004 ◽  
Vol 13 (1) ◽  
pp. 22-43 ◽  
Author(s):  
Tim Burkert ◽  
Jan Leupold ◽  
Georg Passig
Keyword(s):  
Time Delays ◽  
Feedback Loop ◽  
Communication Channel ◽  
Graphics Hardware ◽  
Model Data ◽  
Predictive Display ◽  
Teleoperation System ◽  
Processing Techniques ◽  
Texture Extraction

The quality of a teleoperation system is decreased by time delays in the communication channel. Delays as low as a few hundred milliseconds between commanding an action and getting the visual feedback reduce the operator's performance. Predictive displays have proven their suitability to compensate for these delays, but at the expense of image quality when using computer-generated images. A photorealistic predictive display is presented that closes the feedback loop locally at the operator's side of a telepresence system. Photorealism is achieved using delayed camera images for texturing the predicted scene. Consumer graphics hardware is not only used for rendering but also for hardware-accelerated texture extraction. To allow concurrent access to model data, a multibuffer model structure is presented. A model of the teleoperator's environment is automatically acquired and updated by image processing techniques using a stereo camera as the only sensor.

scholarly journals A New Method for Bilateral Teleoperation Passivity under Varying Time Delays

2012 ◽  
Vol 2012 ◽  
pp. 1-19 ◽  
Author(s):  
Farzad Hashemzadeh ◽  
Iraj Hassanzadeh ◽  
Mahdi Tavakoli ◽  
Ghasem Alizadeh
Keyword(s):  
Time Delays ◽  
Communication Channel ◽  
Time Varying ◽  
Constant Delay ◽  
Time Varying Delay ◽  
Teleoperation System ◽  
Virtual Time ◽  
Varying Delay ◽  
Disturbance Estimator

A new framework is proposed to mitigate the adverse effect of time-varying time delays on the passivity of a teleoperation system. To this end, the communication channel with time-varying delays is modeled as a constant-delay channel along with additive output disturbances. Then, disturbance estimator blocks are added in each of the feedforward and feedback paths to estimate these disturbances and to compensate for them. In the disturbance estimator block, there is a need for a virtual time-varying delay block such that the overall communication channel can be seen as one with a constant delay. We also propose a method for determining this virtual delay. Two PHANToM haptic devices connected through a communication channel with time-varying delays are considered for a case study. Simulation and experimental results confirm the efficiency of the proposed method in terms of passivating the teleoperation system in the presence of time-varying delays.

Impact of Raw Materials and Processing Techniques on The Microbiological Quality of Egyptian Domiati Cheese

2020 ◽  
Keyword(s):  
Raw Materials ◽  
Microbiological Quality ◽  
Raw Milk ◽  
Plate Count ◽  
E Coli ◽  
Fresh Cheese ◽  
Processing Techniques ◽  
The Impact ◽  
Total Yeast

Domiati cheese is the most popular brand of cheese ripened in brine in the Middle East in terms of consumed quantities. This study was performed to investigate the impact of the microbiological quality of the used raw materials, the applied traditional processing techniques and ripening period on the quality and safety of the produced cheese. Three hundred random composite samples were collected from three factories at Fayoum Governorate, Egypt. Collected samples represent twenty-five each of: raw milk, table salt, calf rennet, microbial rennet, water, environmental air, whey, fresh cheese, ripened cheese & swabs from: worker hands; cheese molds and utensils; tanks. All samples were examined microbiologically for Standard Plate Count (SPC), coliforms count, Staphylococcus aureus (S. aureus) count, total yeast & mould count, presence of E. coli, Salmonellae and Listeria monocytogenes (L. monocytogenes). The mean value of SPC, coliforms, S. aureus and total yeast & mould counts ranged from (79×102 CFU/m3 for air to 13×108 CFU/g for fresh cheese), (7×102 MPN/ cm2 for tank swabs to 80×106 MPN/ml for raw milk), (9×102 CFU/g for salt to 69×106 CFU/g for fresh cheese) and (2×102 CFU/cm2 for hand swabs to 60×104 CFU/g for fresh cheese), respectively. Whereas, E. coli, Salmonella and L. monocytogenes failed to be detected in all examined samples. There were significant differences in all determined microbiological parameters (p ≤0.05) between fresh and ripened cheese which may be attributed to different adverse conditions such as water activity, pH, salt content and temperature carried out to improve the quality of the product.

New Monitoring Strategy for the Quality Control in the Processing Practice of Scutellariae Radix

2020 ◽  
Vol 16 (3) ◽  
pp. 303-311
Author(s):  
Qi Huang ◽  
Chunsong Cheng ◽  
Lili Li ◽  
Daiyin Peng ◽  
Cun Zhang
Keyword(s):  
Quality Control ◽  
Monitoring Strategy ◽  
Scutellariae Radix ◽  
Chromatographic Fingerprints ◽  
New Strategy ◽  
Processed Products ◽  
Main Components ◽  
Processing Techniques ◽  
Multivariate Monitoring

Background: Scutellariae Radix (Huangqin) is commonly processed into 3 products for different clinical applications. However, a simple analytical method for quality control has rarely been reported to quickly estimate the degree of processing Huangqin or distinguish differently processed products or unqualified Huangqin products. Objective: To study a new strategy for quality control in the processing practice of Huangqin. Methods: Seven kinds of flavonoids that mainly exist in Huangqin were determined by HPLC-DAD. Chromatographic fingerprints were established to study the variation and discipline of the 3 processed products of Huangqin. PCA and OPLS-DA were used to classify differently processed products of Huangqin. Results: The results showed that baicalin and wogonoside were the main components in the crude and the alcohol Huangqin herb while baicalein and wogonin mainly existed in carbonized Huangqin. The results of mathematical statistics revealed that the processing techniques can make the quality of medicinal materials more uniform. Conclusion: This multivariate monitoring strategy is suitable for quality control in the processing of Huangqin.

A Human/Computer Learning Network to Improve Biodiversity Conservation and Research

AI Magazine ◽  
2012 ◽  
Vol 34 (1) ◽  
pp. 10 ◽  
Author(s):  
Steve Kelling ◽  
Jeff Gerbracht ◽  
Daniel Fink ◽  
Carl Lagoze ◽  
Weng-Keen Wong ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Feedback Loop ◽  
Human Computation ◽  
Computational Power ◽  
Learning Networks ◽  
Learning Network ◽  
Computer Learning ◽  
The Individual ◽  
Citizen Science Project

In this paper we describe eBird, a citizen-science project that takes advantage of the human observational capacity to identify birds to species, which is then used to accurately represent patterns of bird occurrences across broad spatial and temporal extents. eBird employs artificial intelligence techniques such as machine learning to improve data quality by taking advantage of the synergies between human computation and mechanical computation. We call this a Human-Computer Learning Network, whose core is an active learning feedback loop between humans and machines that dramatically improves the quality of both, and thereby continually improves the effectiveness of the network as a whole. In this paper we explore how Human-Computer Learning Networks can leverage the contributions of a broad recruitment of human observers and processes their contributed data with Artificial Intelligence algorithms leading to a computational power that far exceeds the sum of the individual parts.

scholarly journals Clay-Based Brick Porosity Estimation Using Image Processing Techniques

2019 ◽  
Vol 29 (1) ◽  
pp. 1226-1234
Author(s):  
Safa Jida ◽  
Hassan Ouallal ◽  
Brahim Aksasse ◽  
Mohammed Ouanan ◽  
Mohamed El Amraoui ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Image Processing ◽  
Scanning Electron Microscopy ◽  
Computer Vision ◽  
Image Processing Techniques ◽  
Processing Techniques ◽  
Porosity Estimation ◽  
Microscopy Images ◽  
Scanning Electron

Abstract This work intends to apprehend and emphasize the contribution of image-processing techniques and computer vision in the treatment of clay-based material known in Meknes region. One of the various characteristics used to describe clay in a qualitative manner is porosity, as it is considered one of the properties that with “kill or cure” effectiveness. For this purpose, we use scanning electron microscopy images, as they are considered the most powerful tool for characterising the quality of the microscopic pore structure of porous materials. We present various existing methods of segmentation, as we are interested only in pore regions. The results show good matching between physical estimation and Voronoi diagram-based porosity estimation.

scholarly journals A Novel Dissipativity-Based Control for Inexact Nonlinearity Cancellation Problems

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Giacomo Innocenti ◽  
Paolo Paoletti
Keyword(s):  
Control Strategy ◽  
Feedback Loop ◽  
Controller Design ◽  
Natural Control ◽  
Standard Methods ◽  
Approximation Quality ◽  
Linear Controller ◽  
Benchmark System ◽  
Global Linearization

When dealing with linear systems feedback interconnected with memoryless nonlinearities, a natural control strategy is making the overall dynamics linear at first and then designing a linear controller for the remaining linear dynamics. By canceling the original nonlinearity via a first feedback loop, global linearization can be achieved. However, when the controller is not capable of exactly canceling the nonlinearity, such control strategy may provide unsatisfactory performance or even induce instability. Here, the interplay between accuracy of nonlinearity approximation, quality of state estimation, and robustness of linear controller is investigated and explicit conditions for stability are derived. An alternative controller design based on such conditions is proposed and its effectiveness is compared with standard methods on a benchmark system.

ASSESSMENT OF THE APPLICABILITY OF LARAWAN TECHNOLOGIES FOR THE ORGANIZATION OF A BACKUP COMMUNICATION CHANNEL FOR METEOROLOGICAL SUPPORT OF AIRFIELDS

2021 ◽  
pp. 25-31
Author(s):  
Д.К. Тунеголовец
Keyword(s):  
Communication Channel ◽  
Block Diagram ◽  
Essential Feature ◽  
Spatial And Temporal Variability ◽  
Weather Forecasts ◽  
Economic Problems ◽  
Present Information ◽  
The Cost ◽  
Positive Results

В настоящее время информация о состоянии атмосферы широко используется как при составлении прогнозов погоды, так и при решении многих экономических задач. Существенная особенность метеорологических явлений - их пространственно-временная изменчивость. Это вызывает необходимость такой организации наблюдений, которая позволит своевременно отметить возникновение явления и проследить за ходом его развития. Статистика показывает, что в период с 1997 по 2000 годы произошло порядка 193 авиационных инцидентoв, которые обусловлены недостатками метеорологического обеспечения полетов. Поэтому задача повышения качества метеорологического обеспечения является актуальной. На основе модельных и практических экспериментов показано, что беспроводной канал связи LoRaWaN способен объединить весь поток данных, поступающих с удаленных метеорологических датчиков, которые используют разные протоколы для взаимодействия друг с другом. В ходе выполнения эксперимента получены положительные результаты, доказывающие возможность организации таких каналов связи для задач метеообеспечения аэродромов. Также приводится структурная схема для организации канала связи. При этом не требуется прокладка кабельных коммуникаций связи, когда стоимость такого вида работ, включая согласование, зачастую значительно превышает стоимость самого метеорологического оборудования At present, information on the state of the atmosphere is widely used both in the preparation of weather forecasts and in solving many economic problems. An essential feature of meteorological phenomena is their spatial and temporal variability. This makes it necessary to organize observations in such a way that will allow timely noting the occurrence of the phenomenon and monitoring the progress of its development. Statistics show that in the period from 1997 to 2000 there were about 193 aviation incidents, which were caused by shortcomings in the meteorological support of flights. Therefore, the task of improving the quality of meteorological support is urgent. This article shows, based on model and practical experiments, that the LaRaWAN wireless communication channel is able to combine the entire data stream coming from remote meteorological sensors using various communication protocols among themselves. During the experiment, I obtained positive results, proving the possibility of organizing such communication channels for the tasks of meteorological support of airfields. A block diagram for the organization of a communication channel is also provided. At the same time, the laying of cable communications is not required, when the cost of this type of work, including coordination, often significantly exceeds the cost of the meteorological equipment itself

Image Sharpness and Contrast Tuning in the Early Visual Pathway

2017 ◽  
Vol 27 (08) ◽  
pp. 1750045 ◽  
Author(s):  
Eduardo Sánchez ◽  
Rubén Ferreiroa ◽  
Adrián Arias ◽  
Luis M. Martínez
Keyword(s):  
Functional Organization ◽  
Ganglion Cells ◽  
Receptive Fields ◽  
Local Contrast ◽  
Retinal Ganglion ◽  
Image Sharpness ◽  
Image Processing Techniques ◽  
Thalamic Relay ◽  
Processing Techniques

The center–surround organization of the receptive fields (RFs) of retinal ganglion cells highlights the presence of local contrast in visual stimuli. As RF of thalamic relay cells follow the same basic functional organization, it is often assumed that they contribute very little to alter the retinal output. However, in many species, thalamic relay cells largely outnumber their retinal inputs, which diverge to contact simultaneously several units at thalamic level. This gain in cell population as well as retinothalamic convergence opens the door to question how information about contrast is transformed at the thalamic stage. Here, we address this question using a realistic dynamic model of the retinothalamic circuit. Our results show that different components of the thalamic RF might implement filters that are analogous to two types of well-known image processing techniques to preserve the quality of a higher resolution version of the image on its way to the primary visual cortex.

High Tc Oxide Superconductors

MRS Bulletin ◽  
1990 ◽  
Vol 15 (6) ◽  
pp. 31-33
Author(s):  
M. Brian Maple
Keyword(s):  
Physical Properties ◽  
Energy Gap ◽  
Vortex State ◽  
Oxide Superconductors ◽  
High Tc ◽  
Superconducting Energy Gap ◽  
Consistent Picture ◽  
Novel Processing ◽  
Processing Techniques

This issue of the MRS BULLETIN is devoted to high Tc superconductivity. It is the sequel to a previous series of articles on the same subject which appeared in the MRS BULLETIN in January 1989. While the articles in the January 1989 issue emphasized the families of high Tc superconducting oxides known at that rime, as well as novel processing techniques and thin films, the papers in this issue focus on the physical properties of high Tc oxide superconductors.The quality of polycrystalline and single-crystal bulk and thin-film materials has improved to the point where researchers can now make reliable measurements of many physical properties representative of the intrinsic behavior of these materials. As a result, a broad spectrum of important issues such as the nature of the electronic structure, the type of superconducting electron pairing, the magnitude and temperature dependence of the superconducting energy gap, the behavior of fluxoids in the vortex state, etc., can be addressed meaningfully. Presently emerging is a consistent picture of the physical properties of the high Tc oxides, which will form the foundation to eventually developing an appropriate theory for the normal and superconducting states of these remarkable materials.

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