scholarly journals Analysis and Performance Assessment of a Real-Time Correction Pseudo-Correlation Microwave Radiometer for Medical Applications

Electronics ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1427
Author(s):  
Enrique Villa ◽  
Beatriz Aja ◽  
Luisa de la Fuente ◽  
Eduardo Artal ◽  
Natalia Arteaga-Marrero ◽  
...  
Keyword(s):  
Biomedical Application ◽  
Microwave Radiometer ◽  
Noise Temperature ◽  
Temperature Response ◽  
Correlated Response ◽  
Simulated Performance ◽  
Correlation Receiver ◽  
Hybrid Coupler ◽  
Commercial Off The Shelf ◽  
And Performance

A new configuration of a pseudo-correlation type radiometer is proposed for a microwave biomedical application, such as diabetic foot neuropathy. The new approach as well as its simulated performance are thoroughly assessed using commercial off-the-shelf components and custom designed subsystems. We configured a pseudo-correlation receiver, centred at 3.5 GHz, to validate the proposal, comparing its simulated response with a measured alternative based on a 90∘ hybrid coupler pseudo-correlation prototype. We custom designed a balanced Wilkinson power divider and a 180∘ hybrid coupler to fulfil the receiver’s requirements. The proposed configuration demonstrated an improved noise temperature response. The main advantage is to enable the recalibration of the receiver through simultaneous measurable output signals, proportional to each input signal, as well as the correlated response between them.

A New Linearly Polarized Microwave Radiometer Calibration Source

2012 ◽  
Vol 500 ◽  
pp. 341-347
Author(s):  
Xin Biao Wang ◽  
Chang Zeng ◽  
Jing Li ◽  
Jing Shan Jiang
Keyword(s):  
Real Time ◽  
Microwave Radiometer ◽  
Noise Temperature ◽  
Calibration Method ◽  
Calibration Source ◽  
Radiometer Calibration ◽  
Time Calibration ◽  
Linearly Polarized ◽  
Calibration Device

This paper introduces a calibration device for microwave (millimeter and submillimeter) radiometer. The device can provide the microwave radiometer continuously variable linearly polarized noise temperature. The paper also introduces a real-time calibration method to achieve the microwave radiometer calibration, and the test of microwave radiometer sensitivity and linearity.

Estimating Technology Insertion Risk Using Fuzzy Logic

2001 ◽  
Author(s):  
Don Yates ◽  
Alley Butler
Keyword(s):  
Fuzzy Logic ◽  
Limited Information ◽  
Fuzzy Methods ◽  
Schedule Risk ◽  
Fuzzy Logic Method ◽  
Commercial Off The Shelf ◽  
And Performance ◽  
Available Information ◽  
Spread Sheet ◽  
Excel Spread Sheet

Abstract Technology insertion into an existing system or subsystem requires careful planning and evaluation. Because the technology is new, there is often limited information upon which to base decisions. Further, decisions about technology insertion are typically made in the very early stages of a project when detailed information is sparse. Under these circumstances, the available information is typically linguistic, and fuzzy methods can be used to significant advantage in this environment. The implementation discussed in this paper employs an Excel spread sheet for user interface, and it employs COTS (Commercial Off the Shelf Technology) software for an inference engine. Heuristic based models are developed to evaluate risk in technology insertion. Risk elements include: budget risk, schedule risk, and performance risk. Results with an example problem are described to illustrate the fuzzy logic method, and conclusions are drawn regarding the advantages of this technique.

scholarly journals COMPACT AND PERFORMANCE EVALUATION OF BRANCH-LINE HYBRID COUPLER MICROSTRIP FOR LONG TERM EVOLUTION APPLICATIONS

2018 ◽  
Vol 73 ◽  
pp. 53-60 ◽  
Author(s):  
Mahmoud Moubadir ◽  
Hicham Aziz ◽  
Naima Amar Touhami ◽  
Mohamed Aghoutane
Keyword(s):  
Performance Evaluation ◽  
Long Term Evolution ◽  
Branch Line ◽  
Term Evolution ◽  
Hybrid Coupler ◽  
And Performance

scholarly journals SEPIA – a new single pixel receiver at the APEX telescope

2018 ◽  
Vol 612 ◽  
pp. A23 ◽  
Author(s):  
V. Belitsky ◽  
I. Lapkin ◽  
M. Fredrixon ◽  
D. Meledin ◽  
E. Sundin ◽  
...  
Keyword(s):  
State Of The Art ◽  
Noise Temperature ◽  
Intermediate Frequency ◽  
Space Observatory ◽  
Frequency Channel ◽  
Current Frequency ◽  
Onsala Space Observatory ◽  
Hardware Description ◽  
And Performance ◽  
Single Pixel

Context. We describe the new Swedish-ESO PI Instrument for APEX (SEPIA) receiver, which was designed and built by the Group for Advanced Receiver Development (GARD), at Onsala Space Observatory (OSO) in collaboration with ESO. It was installed and commissioned at the APEX telescope during 2015 with an ALMA Band 5 receiver channel and updated with a new frequency channel (ALMA Band 9) in February 2016. Aim. This manuscript aims to provide, for observers who use the SEPIA receiver, a reference in terms of the hardware description, optics and performance as well as the commissioning results. Methods. Out of three available receiver cartridge positions in SEPIA, the two current frequency channels, corresponding to ALMA Band 5, the RF band 158–211 GHz, and Band 9, the RF band 600–722 GHz, provide state-of-the-art dual polarization receivers. The Band 5 frequency channel uses 2SB SIS mixers with an average SSB noise temperature around 45 K with IF (intermediate frequency) band 4–8 GHz for each sideband providing total 4 × 4 GHz IF band. The Band 9 frequency channel uses DSB SIS mixers with a noise temperature of 75–125 K with IF band 4–12 GHz for each polarization. Results. Both current SEPIA receiver channels are available to all APEX observers.

Performance and Simulated Performance Test Results as a Function of Instruction by Still and Motion Visuals

1981 ◽  
Vol 10 (1) ◽  
pp. 33-44 ◽  
Author(s):  
Unna H. Jeon ◽  
Robert K. Branson
Keyword(s):  
Motor Skills ◽  
Performance Test ◽  
Visual Media ◽  
Performance Tests ◽  
Test Results ◽  
Simulated Performance ◽  
Instructional Objectives ◽  
And Performance ◽  
Written Test ◽  
Better Than

This study evaluates the effectiveness of three different media in teaching a specific motor skill. Validated lessons utilizing three different media — motion/sound, slide/sound, and story boards — were used to teach basic manipulations of the M203 Grenade Launcher. Written and performance tests, derived directly from the instructional objectives, were used to evaluate the learning. As evaluated by the performance test, learners using motion film performed significantly better than those using either slides or workbooks, and required significantly less time. Written tests, however, failed to detect this difference. These results suggest that much previous research comparing media may have been inconclusive due to defects in experimental design, such as using a written test to measure motor skills taught by visual media.

scholarly journals Diagnostics-Oriented Modelling of Micro Gas Turbines for Fleet Monitoring and Maintenance Optimization

Processes ◽  
2018 ◽  
Vol 6 (11) ◽  
pp. 216 ◽  
Author(s):  
Moksadur Rahman ◽  
Valentina Zaccaria ◽  
Xin Zhao ◽  
Konstantinos Kyprianidis
Keyword(s):  
Gas Turbine ◽  
Gas Turbines ◽  
Performance Monitoring ◽  
High Reliability ◽  
Small Scale ◽  
Power Generators ◽  
Micro Gas Turbine ◽  
Commercial Off The Shelf ◽  
And Performance ◽  
The Cost

The market for the small-scale micro gas turbine is expected to grow rapidly in the coming years. Especially, utilization of commercial off-the-shelf components is rapidly reducing the cost of ownership and maintenance, which is paving the way for vast adoption of such units. However, to meet the high-reliability requirements of power generators, there is an acute need of a real-time monitoring system that will be able to detect faults and performance degradation, and thus allow preventive maintenance of these units to decrease downtime. In this paper, a micro gas turbine based combined heat and power system is modelled and used for development of physics-based diagnostic approaches. Different diagnostic schemes for performance monitoring of micro gas turbines are investigated.

The Seasat scanning multichannel microwave radiometer (SMMR): Instrument description and performance

1980 ◽  
Vol 5 (2) ◽  
pp. 100-115 ◽  
Author(s):  
Eni Njoku ◽  
J. Stacey ◽  
Frank Barath
Keyword(s):  
Microwave Radiometer ◽  
And Performance

Aircrew Performance and Safety While Using Protective Masks in Response to Coronavirus Disease

2021 ◽  
Vol 92 (4) ◽  
pp. 274-280
Author(s):  
Kara M. Cave ◽  
Amanda M. Kelley ◽  
Kathryn A. Feltman ◽  
Jason A. Gerstner ◽  
Justin L. Stewart ◽  
...  
Keyword(s):  
Traffic Control ◽  
Speech Intelligibility ◽  
Air Traffic ◽  
Respiratory Protection ◽  
Radio Communications ◽  
The Face ◽  
Commercial Off The Shelf ◽  
And Performance ◽  
The Impact ◽  
Modified Rhyme Test

INTRODUCTION: In response to the urgent need for safe aircrew respiratory protection due to the COVID-19 pandemic, three small descriptive evaluations were conducted with aircrew and air traffic controllers (ATC) that assessed the impact of mask use on safety and performance onboard rotary wing aircraft.METHODS: A series of evaluations assessed aircrew performance using the 3MTM Model 1860 N95 respiratory protection mask, two aviation-specific cloth mask prototypes, and a commercial off-the-shelf aviation-specific cloth mask. The series of evaluations included different sets of subjects consisting of up to five Black Hawk helicopter aircrew members, air traffic control (ATC), and 12 CH-47 aircrew members. The Modified Rhyme Test was used to measure speech intelligibility and was administered in the UH-60 among crewmembers of the same aircraft, between pilots of different aircraft, and between the pilots and ATC. Measures of workload, usability, comfort, and pulse oximetry were also administered.RESULTS: Results from the Modified Rhyme Test indicated that all subjects scored greater than 80% accuracy given the proper microphone positioning relative to the mask. With respect to workload, NASA-TLX total scores for the perform radio communications task was 50.83.DISCUSSION: Despite an elevated perceived degree of workload on the communications flight task, results from the speech intelligibility test indicated that performance was maintained within the acceptable range as defined by MIL-STD-1474E, Design Criteria Standard Noise Limit. This abbreviated evaluation suggests that the face masks tested are safe for use by helicopter aircrew under the conditions tested.Cave KM, Kelley AM, Feltman KA, Gerstner JA, Stewart JL, Crowley JS. Aircrew performance and safety while using protective masks in response to coronavirus disease. Aerosp Med Hum Perform. 2021; 92(4):274280.

Equipment Standardization Under Acquisition Reform

1998 ◽  
Vol 14 (02) ◽  
pp. 110-123
Author(s):  
Jan Sands ◽  
William Loughlin ◽  
Frank Lu
Keyword(s):  
Department Of Defense ◽  
Construction Process ◽  
Best Value ◽  
Acquisition Strategies ◽  
Large Numbers ◽  
Acquisition Reform ◽  
Commercial Off The Shelf ◽  
And Performance ◽  
System Approaches ◽  
Commercial Equipment

This paper discusses the ramifications of current Department of Defense (DoD) Acquisition Reform policies on Navy equipment standardization initiatives and provides an overview of the objectives and benefits of making "best value" end item selections during the design and construction process. The DoD initiative to implement acquisition reform by changing the processes by which defense system and equipment requirements are defined and communicated to contractors is having significant impacts on equipment standardization programs. The emphasis on the use of non-developmental and commercial-off-the-shelf items (NDIs/COTS) combined with naval ship system and equipment requirements being expressed primarily in performance terms creates the potential for the introduction of large numbers of commercial equipment to the supply support system. Approaches to maximizing equipment standardization efforts in the era of commercial-based acquisition strategies are described and examples of standardization approaches using recent ship acquisitions (Strategic Sealift, LHD 1, DDG 51, and LPD 17) are presented.. Possible approaches for the use of performance-based equipment databases and real-time linkages through the Internet with COTS manufacturers are discussed. Impacts that could change the structure of existing logistics support systems and result in substantial improvements in both cost and performance of shipboard equipment and components are addressed.

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