scholarly journals High Reliability Evaluation and Lifetime Prediction of 50 GHz Athermal AWG Module

2021 ◽  
Vol 11 (23) ◽  
pp. 11107
Author(s):  
Kwang-Su Yun ◽  
Chong-Hee Yu ◽  
Kwon-Seob Lim ◽  
Young-Sic Kim ◽  
Insu Jeon
Keyword(s):  
Temperature Dependence ◽  
Insertion Loss ◽  
High Reliability ◽  
Accelerated Life Testing ◽  
Center Wavelength ◽  
Accelerated Life ◽  
Outdoor Environments ◽  
Indoor And Outdoor Environments ◽  
Nm Range

A 96-channel (50 GHz-spacing) athermal AWG has been developed. It has a wide operating range due to reduced temperature dependence than conventional AWG. The temperature dependence of the center wavelength of the developed module satisfied the ±0.05 nm range in all channels in the temperature range of −40 °C to 85 °C, and the insertion loss variation was also less than ±0.5 dB. As a result of validating its reliability through tests based on Telcordia-GR-1209 and GR-1221, the temperature dependence of the center wavelength satisfied the ±0.022 nm range, and the insertion loss variation was also less than ±0.2 dB. Accelerated life testing showed an expected service life of over 36.7 years, ensuring long-term safety of communication quality in harsh indoor and outdoor environments.

Accelerated Life Testing under Variable Synthetic Stresses for Hydraulic Pump

2006 ◽  
Vol 505-507 ◽  
pp. 1165-1170 ◽  
Author(s):  
Shao Ping Wang ◽  
Jian Shi
Keyword(s):  
Normal Stress ◽  
High Reliability ◽  
Accelerated Life Testing ◽  
Cumulative Exposure ◽  
Test Time ◽  
Stress Profile ◽  
Life Testing ◽  
Hydraulic Pump ◽  
Accelerated Life ◽  
Life Model

Life testing is an important technique to assess the reliability and lifetime of components with long life and high reliability. To some expensive products, it is difficult to supply a large of samples and long test time to carry out the life testing, so this paper investigates the accelerated model and presents statistical method based on hybrid Weibull distribution under variable synthetic stresses. Based on the cumulative exposure theory, the failure probability can be cumulated with transform rate that can convert the fault proportion at certain stress into another stress. Using the genetic algorithm, the parameters of accelerated model can be estimated according to the accelerated stress profile. Then the lifetime at normal stress can be calculated with accelerated life model under normal stress profile. Application of hydraulic pump indicates that this method can reduce test time and test samples greatly.

scholarly journals Long-Term and Accelerated Life Testing of a Novel Single-Wafer Vacuum Encapsulation for MEMS Resonators

2006 ◽  
Vol 15 (6) ◽  
pp. 1446-1456 ◽  
Author(s):  
Rob N. Candler ◽  
Matthew A. Hopcroft ◽  
Bongsang Kim ◽  
Woo-Tae Park ◽  
Renata Melamud ◽  
...  
Keyword(s):  
Accelerated Life Testing ◽  
Life Testing ◽  
Mems Resonators ◽  
Accelerated Life

scholarly journals Reliability and Remaining Life Assessment of an Electronic Fuze Using Accelerated Life Testing

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 272
Author(s):  
Noor Muhammad ◽  
Zhigeng Fang ◽  
Syed Yaseen Shah ◽  
Daniyal Haider
Keyword(s):  
High Reliability ◽  
Storage Life ◽  
Remaining Useful Life ◽  
Accelerated Life Testing ◽  
Life Assessment ◽  
Weak Links ◽  
Life Testing ◽  
Accelerated Life ◽  
Useful Life ◽  
Mission Critical

An electronic fuze is a one-shot system that has a long storage life and high mission criticality. Fuzes are designed, developed, and tested for high reliability (over 99%) with a confidence level of more than 95%. The electronic circuit of a fuze is embedded in the fuze assembly, and thus is not visible. Go/NoGo fuze assembly mission critical testing does not provide prognostic information about electrical and electronic circuits and subtle causes of failure. Longer storage times and harsh conditions cause degradation at the component level. In order to calculate accrued damage due to storage and operational stresses, it is necessary to perform sample-based accelerated life testing after a certain time and estimate the remaining useful life of mission critical parts. Reliability studies of mechanical parts of such systems using nondestructive testing (NDT) have been performed, but a thorough investigation is missing with regards to the electronic parts. The objective of this study is to identify weak links and estimate the reliability and remaining useful life of electronic and detonating parts. Three critical components are identified in an electronic fuze circuit (1) a diode, (2) a capacitor, and (3) a squib or detonator. The accelerated test results reveal that after ten years of storage life, there is no significant degradation in active components while passive components need to be replaced. The squib has a remaining useful life (RUL) of more than ten years with reliability over 99%.

ACCELERATED LIFE TESTING OF COMPONENTS OF NUCLEAR RESEARCH REACTORS

2016 ◽  
Author(s):  
Vanderley Vasconcelos ◽  
WELLINGTON SOARES ◽  
Antonio Carlos Lopes da Costa ◽  
Raíssa Oliveira Marques
Keyword(s):  
Nuclear Research ◽  
Accelerated Life Testing ◽  
Life Testing ◽  
Research Reactors ◽  
Accelerated Life

Impacts of Different Winter Storage Conditions on the Physiology of Diutinus Honey Bees (Hymenoptera: Apidae)

2021 ◽  
Author(s):  
Brandon K Hopkins ◽  
Priyadarshini Chakrabarti ◽  
Hannah M Lucas ◽  
Ramesh R Sagili ◽  
Walter S Sheppard
Keyword(s):  
Honey Bees ◽  
The United States ◽  
Storage Conditions ◽  
Colony Losses ◽  
Bee Colony ◽  
Causative Factors ◽  
Outdoor Environments ◽  
Indoor And Outdoor Environments ◽  
Physiological Markers ◽  
Honey Bee Colony Losses

Abstract Global decline in insect pollinators, especially bees, have resulted in extensive research into understanding the various causative factors and formulating mitigative strategies. For commercial beekeepers in the United States, overwintering honey bee colony losses are significant, requiring tactics to overwinter bees in conditions designed to minimize such losses. This is especially important as overwintered honey bees are responsible for colony expansion each spring, and overwintered bees must survive in sufficient numbers to nurse the spring brood and forage until the new ‘replacement’ workers become fully functional. In this study, we examined the physiology of overwintered (diutinus) bees following various overwintering storage conditions. Important physiological markers, i.e., head proteins and abdominal lipid contents were higher in honey bees that overwintered in controlled indoor storage facilities, compared with bees held outdoors through the winter months. Our findings provide new insights into the physiology of honey bees overwintered in indoor and outdoor environments and have implications for improved beekeeping management.

scholarly journals A Hybrid Framework for Mitigating Heading Drift for a Wearable Pedestrian Navigation System through Adaptive Fusion of Inertial and Magnetic Measurements

2021 ◽  
Vol 11 (4) ◽  
pp. 1902
Author(s):  
Liqiang Zhang ◽  
Yu Liu ◽  
Jinglin Sun
Keyword(s):  
Magnetic Measurements ◽  
Inertial Sensor ◽  
Angular Rate ◽  
Human Motion ◽  
Navigation Systems ◽  
Pedestrian Navigation ◽  
Hybrid Framework ◽  
Outdoor Environments ◽  
Adaptive Fusion ◽  
Indoor And Outdoor Environments

Pedestrian navigation systems could serve as a good supplement for other navigation methods or for extending navigation into areas where other navigation systems are invalid. Due to the accumulation of inertial sensing errors, foot-mounted inertial-sensor-based pedestrian navigation systems (PNSs) suffer from drift, especially heading drift. To mitigate heading drift, considering the complexity of human motion and the environment, we introduce a novel hybrid framework that integrates a foot-state classifier that triggers the zero-velocity update (ZUPT) algorithm, zero-angular-rate update (ZARU) algorithm, and a state lock, a magnetic disturbance detector, a human-motion-classifier-aided adaptive fusion module (AFM) that outputs an adaptive heading error measurement by fusing heuristic and magnetic algorithms rather than simply switching them, and an error-state Kalman filter (ESKF) that estimates the optimal systematic error. The validation datasets include a Vicon loop dataset that spans 324.3 m in a single room for approximately 300 s and challenging walking datasets that cover large indoor and outdoor environments with a total distance of 12.98 km. A total of five different frameworks with different heading drift correction methods, including the proposed framework, were validated on these datasets, which demonstrated that our proposed ZUPT–ZARU–AFM–ESKF-aided PNS outperforms other frameworks and clearly mitigates heading drift.

scholarly journals Health Effects and Exposure Assessment to Bioaerosols in Indoor and Outdoor Environments

Atmosphere ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 359
Author(s):  
Ewa Brągoszewska
Keyword(s):  
Exposure Assessment ◽  
Health Effects ◽  
Special Issue ◽  
Outdoor Environments ◽  
Indoor And Outdoor Environments ◽  
Indoor And Outdoor

The Atmosphere Special Issue entitled “Health Effects and Exposure Assessment to Bioaerosols in Indoor and Outdoor Environments” comprises five original papers [...]

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