Assessment of UV Sensors for Flameout Detection

Author(s):  
Edouard Bahous ◽  
Ram Srinivasan ◽  
Priyank Saxena ◽  
John Bowen

UV sensors were tested to evaluate the response and reliability as a flameout detection system to reduce system level risks. In this study, UV sensors from two manufacturers were tested on high pressure experimental rigs and on a 15MW gas turbine engine with annular diffusion flame combustion system. Tests were run to investigate the effect of fuel composition, engine load, and sensor circumferential position. The effect of each variable on sensor signal strength and response time is presented in this paper. The response time of the sensor is evaluated against the rate of change of combustor pressure and the time for fuel-air mixture to reach lean extinction limit in the primary zone. Results show that the UV sensor response is not affected by engine load, circumferential location of the sensors, or fuel composition down to Wobbe index of 18.7 MJ/Sm3. At lower Wobbe indices, the signal strength decreased significantly. This result has been attributed to the movement of flame location away from the line of sight of the sensor. Furthermore, it was found that the UV sensor responded before the bulk average reactant mixture reached lean blow out fuel-air ratios. When compared to the baseline detection system the UV sensor performs faster at low load conditions (800 milliseconds) but slower at full load conditions (400 milliseconds). Experimental rig testing led to similar conclusions for sensor response time and signal strength. Future testing of UV sensors on hydrogen blends is planned.

1997 ◽  
Vol 473 ◽  
Author(s):  
J. A. Davis ◽  
J. D. Meindl

ABSTRACTOpportunities for Gigascale Integration (GSI) are governed by a hierarchy of physical limits. The levels of this hierarchy have been codified as: 1) fundamental, 2) material, 3) device, 4) circuit and 5) system. Many key limits at all levels of the hierarchy can be displayed in the power, P, versus delay, td, plane and the reciprocal length squared, L-2, versus response time, τ, plane. Power, P, is the average power transfer during a binary switching transition and delay, td, is the time required for the transition. Length, L, is the distance traversed by an interconnect that joins two nodes on a chip and response time, τ, characterizes the corresponding interconnect circuit. At the system level of the hierarchy, quantitative definition of both the P versus td and the L-2 versus τ displays requires an estimate of the complete stochastic wiring distribution of a chip.Based on Rent's Rule, a well known empirical relationship between the number of signal input/output terminals on a block of logic and the number of gate circuits with the block, a rigorous derivation of a new complete stochastic wire length distribution for an on-chip random logic network is described. This distribution is compared to actual data for modern microprocessors and to previously described distributions. A methodology for estimating the complete wire length distribution for future GSI products is proposed. The new distribution is then used to enhance the critical path model that determines the maximum clock frequency of a chip; to derive a preliminary power dissipation model for a random logic network; and, to define an optimal architecture of a multilevel interconnect network that minimizes overall chip size. In essence, a new complete stochastic wiring distribution provides a generic basis for maximizing the value obtained from a multilevel interconnect technology.


2021 ◽  
pp. 1-13
Author(s):  
Dayong Guo ◽  
Qing Hu

Aiming at the problems of low precision, slow data transmission speed and long response time of silk quality and temperature control in tobacco intelligent production line, a multi-index testing system is designed. According to the characteristics of PROFIBUS fieldbus technology, combined with PROFIBUS transmission technology, a factory level information network is formed with PROFIBUS-DP as the exchange mode. Based on the PROFIBUS technology, the dual redundancy structure of control ring network and management information ring network is adopted, and the whole network architecture is constructed by logic layering. From the point of view of building enterprise MES system, it locates real-time production monitoring, production task receiving and production line related data collection, integrates equipment control layer, centralized monitoring layer and production management layer, and designs system function structure. The functional structure of the system, and the establishment of a number of data tables, to achieve a tobacco intelligent production line silk quality detection system design. Experimental results show that this method can effectively speed up the data transmission speed and shorten the system response time.


10.2196/21243 ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. e21243
Author(s):  
Caitlin Horsham ◽  
Jodie Antrobus ◽  
Catherine M Olsen ◽  
Helen Ford ◽  
David Abernethy ◽  
...  

Background Australia and New Zealand have the highest skin cancer incidence rates worldwide, and sun exposure is the main risk factor for developing skin cancer. Sun exposure during childhood and adolescence is a critical factor in developing skin cancer later in life. Objective This study aims to test the effectiveness of wearable UV sensors to increase sun protection habits (SPH) and prevent sunburn in adolescents. Methods During the weeklong school leavers outdoor festival (November 2019) at the Gold Coast, Australia, registered attendees aged 15-19 years were recruited into the field study. Participants were provided with a wearable UV sensor and free sunscreen. The primary outcome was sun exposure practices using the SPH index. Secondary outcomes were self-reported sunburns, sunscreen use, and satisfaction with the wearable UV sensor. Results A total of 663 participants were enrolled in the study, and complete data were available for 188 participants (188/663, 28.4% response rate). Participants provided with a wearable UV sensor significantly improved their use of sunglasses (P=.004) and sunscreen use both on the face (P<.001) and on other parts of the body (P=.005). However, the use of long-sleeve shirts (P<.001) and the use of a hat (P<.001) decreased. During the study period, 31.4% (59/188) of the participants reported receiving one or more sunburns. Satisfaction with the wearable UV sensor was high, with 73.4% (138/188) of participants reporting the UV sensor was helpful to remind them to use sun protection. Conclusions Devices that target health behaviors when outdoors, such as wearable UV sensors, may improve use of sunscreen and sunglasses in adolescents.


2019 ◽  
Vol 7 (4) ◽  
pp. 162-176
Author(s):  
Rajendran N. ◽  
Jawahar P.K. ◽  
Priyadarshini R.

Purpose The purpose of this paper is to apply security policies over the mobile ad hoc networks. A mobile ad hoc network refers to infrastructure-less, persistently self-designing systems; likewise, there is a noteworthy innovation that supplies virtual equipment and programming assets according to the requirement of mobile ad hoc network. Design/methodology/approach It faces different execution and effectiveness-based difficulties. The major challenge is the compromise of performance because of unavailable resources with respect to the MANET. In order to increase the MANET environment’s performance, various techniques are employed for routing and security purpose. An efficient security module requires a quality-of-service (QoS)-based security policy. It performs the task of routing and of the mobile nodes, and it also reduces the routing cost by finding the most trusted node. Findings The experimental results specify that QoS-based security policy effectively minimizes the cost, response time as well as the mobile makespan (routing cost and response time) of an application with respect to other existing approaches. Research limitations/implications In this paper, the authors proposed an enhancement of Cross Centric Intrusion Detection System named as PIHNSPRA Routing Algorithm (PIHNSPRA). Practical implications It maps the security with the secure IDS communication and distributes the packets among different destinations, based on priority. This calculation is proposed for the purpose of routing and security by considering greatest throughput with least routing cost and reaction time. Social implications When the concept is applied to practical applications. Quality of Service introduced in the proposed research reduces the cost of routing and improves the throughput. Originality/value The proposed calculation is tested by NS2 simulator and the outcomes showed that the execution of the calculation is superior to other conventional algorithms.


2019 ◽  
Vol 186 (2-3) ◽  
pp. 406-412
Author(s):  
Petra Vyletělová ◽  
Aleš Froňka

Abstract The extraction of dissolved radon from water to gas is the most common way to measure radon concentration in water continuously. The response delay of continuous radon-in-water detection system (continuous monitor + equilibrator) is influenced by the response time of the continuous monitor and a rate of an establishment of equilibrium in the equilibrator (exchanger unit). Two types of equilibrators were used in performed experiments to compare the response time of various detection systems—RAD AQUA that uses water spraying and equilibrator with ACCUREL® PP membrane that enables radon diffusion. Each of these was connected to the continuous monitor RAD7 or RM-3. The response delay after turning on the water flow through the equilibrator was determined. The fastest detection system was RAD7 + RAD AQUA that was subsequently tested during the insitu measurement of thermal water in the healing spa and water sources near Cheb and České Budějovice.


Biosensors ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 60 ◽  
Author(s):  
Uswatun Hasanah ◽  
Mita Setyowati ◽  
Rustam Efendi ◽  
Muslem Muslem ◽  
Nor Diyana Md Sani ◽  
...  

In a simple and instant procedure for detecting fish freshness, a hydrogel and hydrophilic pectin matrix membrane was used successfully as an optical pH sensor by immobilizing the chromoionophore ETH 5294 (CI), which is very selective and sensitive for the membrane. The Pe/CI optical pH sensor exhibited excellent linearity between pH 5 and pH 9, with a sensor response time of 5 min and reproducibility of 1.49% relative standard deviation (RSD). The sensor showed response stability for 15 days and a response reduction of 8.6%. The sensor’s capability was demonstrated by the detection of fish freshness for 17 days at 4 °C.


2011 ◽  
Vol 287-290 ◽  
pp. 1976-1979
Author(s):  
Lin Cai Ma ◽  
Zhi Guo Zhou ◽  
Liang Yao Xia ◽  
Da Xue Liu ◽  
Xiao Li Yu

A bench tests were carried out on an YC6J190 diesel engine fueled with B20 marine biodiesel. The results showed that the engine’s effective power decreased by 1.8%, the fuel consumption rate increased by 0.07%, HC emissions decreased by 19.17% and the soot decreased by 25% as average under full engine load conditions. HC decreased by 23.4% and the soot decreased by 23% as average under part engine load conditions. The soot emissions decreased by 28.8% as average under the free acceleration conditions.


Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 958 ◽  
Author(s):  
Tao Qin ◽  
Bo Wang ◽  
Ruoya Chen ◽  
Zunying Qin ◽  
Lei Wang

System security monitoring has become more and more difficult with the ever-growing complexity and dynamicity of the Internet of Things (IoT). In this paper, we develop an Intelligent Maintenance and Lightweight Anomaly Detection System (IMLADS) for efficient security management of the IoT. Firstly, unlike the traditional system use static agents, we employ the mobile agent to perform data collection and analysis, which can automatically transfer to other nodes according to the pre-set monitoring task. The mobility is handled by the mobile agent running platform, which is irrelevant with the node or its operation system. Combined with this technology, we can greatly reduce the number of agents running in the system while increasing the system stability and scalability. Secondly, we design different methods for node level and system level security monitoring. For the node level security monitoring, we develop a lightweight data collection and analysis method which only occupy little local computing resources. For the system level security monitoring, we proposed a parameter calculation method based on sketch, whose computational complexity is constant and irrelevant with the system scale. Finally, we design agents to perform suitable response policies for system maintenance and abnormal behavior control based on the anomaly mining results. The experimental results based on the platform constructed show that the proposed method has lower computational complexity and higher detection accuracy. For the node level monitoring, the time complexity is reduced by 50% with high detection accuracy. For the system level monitoring, the time complexity is about 1 s for parameter calculation in a middle scale IoT network.


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