scholarly journals Study on Smoke Detector Characteristics Using Fire Simulations

2021 ◽  
Vol 35 (4) ◽  
pp. 8-14
Author(s):  
Ga-Hyeon Lee ◽  
Sung-Eun Lee ◽  
Si-Kuk Kim ◽  
Seung-Chul Lee
Keyword(s):  
Optical Density ◽  
Preliminary Data ◽  
Performance Testing ◽  
Wood Smoke ◽  
Smoke Detector ◽  
Experimental Conditions ◽  
Smoke Detectors ◽  
Fire Detector ◽  
Technical Specifications ◽  
Fire Experiments

To reduce the damage caused by fire detector malfunctions, we investigated the standards and literature pertaining to fire detectors in Korea. The domestic standards cite UL's technical specifications, which provide only the standards and types of combustible materials; however, additional research is needed because no facilities related to the experiments are investigated and no fire experiments have actually been conducted. In this study, we refer to UL 268, which is similar to the domestic standards, as well as detailed experimental conditions and methods to improve smoke detector performances; we also use wood as the combustion material from among the fire sources specified in UL 268. Experiments were conducted to measure the sensitization rates using an optical density meter and repeated to match the wood smoke profile standard provided in UL 268. Furthermore, we compared the smoke concentrations detected by the smoke detectors in the fire experiments with those from fire simulations using FDS software to confirm the detector characteristics. Through these comparisons, we show that this research could be used as preliminary data for performance testing of detectors using UL 268.

scholarly journals Methods of instrument testing of smoke detectors performance

2018 ◽  
Vol 245 ◽  
pp. 11005 ◽  
Author(s):  
Sergey Dubov ◽  
Igor Babikov ◽  
Mihail Vasilyev ◽  
Leonid Tanklevsky
Keyword(s):  
Rapid Diagnosis ◽  
Smoke Detector ◽  
Fire Alarm ◽  
The Real ◽  
Relevant Task ◽  
Instrument Testing ◽  
Smoke Detectors ◽  
Fire Detector

This article is devoted to the currently relevant task - determining the real operability of the smoke detector and developing a method for the rapid diagnosis of fire detectors included in the fire alarm loop. In the process, the sensitivity of the smoke optoelectronic fire detector was checked.

scholarly journals Alat Pendeteksi Kebakaran Menggunakan SMS

2020 ◽  
Vol 1 (2) ◽  
pp. 251-254
Author(s):  
Sindi Permata Sari ◽  
Oriza Candra ◽  
Jhefri Asmi
Keyword(s):  
Human Factors ◽  
Temperature Sensor ◽  
Human Life ◽  
Fire Detection ◽  
Smoke Detectors ◽  
Fire Detector ◽  
Arduino Uno ◽  
Main Component ◽  
The Brain ◽  
Early Fire Detection

Lately, there are frequent fires caused by human factors. Because we cannot predict the process of fire in advance. And the delay in knowing the occurrence of a fire is very fatal to the safety of human life and property. With advances in technology, we can overcome fires by making early fire detection devices. With the presence of temperature and smoke detectors, we can detect fires as early as possible and be delivered quickly via alarms and SMS gateways. The main component of this fire detector is the Arduino Uno. This Arduino uno acts as the brain of the fire detection device. This tool works based on the detection of the temperature condition by the DHT11 temperature sensor, which is when the temperature is above normal, an alert notification will be sent via the SMS gateway and so will the MQ2 smoke and the buzzer will sound as a warning alarm.

A Successful City-Wide Smoke Detector Giveaway Program

PEDIATRICS ◽  
1985 ◽  
Vol 75 (1) ◽  
pp. 14-18 ◽  
Author(s):  
Richard L. Gorman ◽  
Evan Charney ◽  
Neil A. Holtzman ◽  
Kenneth B. Roberts
Keyword(s):  
High Risk ◽  
Fire Risk ◽  
Smoke Detector ◽  
High Risk Population ◽  
Inexpensive Method ◽  
Baltimore City ◽  
Risk Of Death ◽  
Smoke Detectors ◽  
Almost All ◽  
House Fires

Each year, 5,000 Americans die and 300,000 are hospitalized as a result of 2.8 million residential fires. Almost all house fires allow time for safe exit if an early warning is given. Smoke detectors are an effective, reliable, and inexpensive method of providing such warning. After an upsurge of deaths related to fires in 1982, Baltimore City gave away 3,720 smoke detectors to households that requested them. This study addressed two questions: (1) Did the households that received the smoke detectors install them? (2) Was the population reached by this giveaway program a population at high risk from fire? A survey of 231 randomly selected households among those requesting smoke detectors was conducted 8 to 10 months after the giveaway program. At that time, smoke detectors were installed in 92% (212/231) of the homes and 88% (187/212) of the installed smoke detectors were operational. Households requesting smoke detectors were in census tracts at higher risk from fire. The correlation coefficient between the rate of requesting a smoke detector and the risk of death or injury related to fires was r = .90, P < .001. The 231 surveyed households had more personal fire risk factors than the general population. The success of this smoke detector giveaway program is notable in that it required the active participation of a high-risk population.

Safe and Sound: Designing the Vocal Smoke Detector

2008 ◽  
Vol 16 (3) ◽  
pp. 26-28
Author(s):  
Rob Tannen ◽  
Mathieu Turpault
Keyword(s):  
Human Factors ◽  
Development Process ◽  
Smoke Detector ◽  
Next Generation ◽  
Design And Development ◽  
Household Product ◽  
Smoke Detectors ◽  
Effective Design ◽  
Human Factors Research

The design of the vocal smoke detector incorporated psychoacoustic research to more effectively waken children. It also provided an opportunity to examine and improve the usability of an often-overlooked but critical household product. Human factors research into existing smoke detectors identified ergonomic and interaction opportunities in installation and use, which were addressed by an effective design and development process. The result of this effort was not just an appealing and usable product but a next-generation smoke detector that enhances safety by design.

scholarly journals Continuous Registration of Thrombin Generation in Plasma, Its Use for the Determination of the Thrombin Potential

1993 ◽  
Vol 70 (04) ◽  
pp. 617-624 ◽  
Author(s):  
H C Hemker ◽  
S Wielders ◽  
H Kessels ◽  
S Béguin
Keyword(s):  
Optical Density ◽  
Thrombin Generation ◽  
Time Course ◽  
Enzyme Concentration ◽  
Amidolytic Activity ◽  
Experimental Conditions ◽  
Time Integral ◽  
Α2 Macroglobulin ◽  
Substrate Conversion ◽  
Activity Curve

SummaryA method is described by which the time-course of thrombin generation in plasma can be obtained from a continuous optical density recording of p-nitroaniline (pNA) production in a 2:3 diluted plasma. A chromogenic substrate, methylmalonyl-methylanalyl-arginyl-pNA (SQ68), is used that is specifically split by thrombin but at a low rate. The thrombin that appears and disappears in the plasma does not split more than 5% of the substrate added, so the rate of substrate conversion is in good approximation proportional to the amidolytic activity in the plasma over the entire period of thrombin generation. The course of the enzyme concentration can be calculated from the amidolytic activity curve. It is shown that the thrombin generation curves obtained in this way are essentially identical to those obtained via the classical subsampling method.The presence of SQ 68 influences the amount of free thrombin that appears in plasma because it competitively inhibits the inactivation of thrombin by AT III and α2 macroglobulin. The inhibition of the thrombin peak by heparin, relative to an uninhibited control, remains unaltered by the presence of the substrate.From the course of thrombin activity and the prevailing decay constants, the course of prothrombin conversion velocity can be calculated. Prothrombin conversion was seen to be inhibited at high (>500 μM) substrate concentrations only, and experimental conditions are found under which the inhibition of the clotting process by the substrate is negligibleThe amidolytic activity is the sum of the activities of free thrombin and of the α2 macroglobulin-thrombin complex formed. Via a mathematical procedure the amount of SQ 68 that has been split by thrombin alone and not by the a2 macroglobulin-thrombin complex, can be derived from the course of the optical density.The total amount of SQ 68 eventually split by thrombin alone is proportional to the surface under the thrombin generation curve, i. e. to the time-integral of free thrombin. This value, that we call the thrombin potential (TP), directly indicates how much of any physiological substrate can potentially be split by the thrombin being generated in the plasma.

scholarly journals Effects of Multisession Anodal Electrical Stimulation of the Auditory Cortex on Temporary Noise-Induced Hearing Loss in the Rat

2021 ◽  
Vol 15 ◽  
Author(s):  
Iván Díaz ◽  
Ana Cecilia Colmenárez-Raga ◽  
David Pérez-González ◽  
Venezia G. Carmona ◽  
Ignacio Plaza Lopez ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Optical Density ◽  
Outer Hair Cell ◽  
Acoustic Trauma ◽  
Experimental Conditions ◽  
Compensatory Response ◽  
Epidural Stimulation ◽  
Efferent System ◽  
Efferent Neurons ◽  
Experimental Approaches

The protective effect of the efferent system against acoustic trauma (AT) has been shown by several experimental approaches, including damage to one ear, sectioning of the olivocochlear bundle (OCB) in the floor of the IV ventricle, and knock-in mice overexpressing outer hair cell (OHC) cholinergic receptors, among others. Such effects have been related to changes in the regulation of the cholinergic efferent system and in cochlear amplification, which ultimately reverse upon protective hearing suppression. In addition to well-known circuits of the brainstem, the descending corticofugal pathway also regulates efferent neurons of the olivary complex. In this study, we applied our recently developed experimental paradigm of multiple sessions of electrical stimulation (ES) to activate the efferent system in combination with noise overstimulation. ABR thresholds increased 1 and 2 days after AT (8–16 kHz bandpass noise at 107 dB for 90 min) recovering at AT + 14 days. However, after multiple sessions of epidural anodal stimulation, no changes in thresholds were observed following AT. Although an inflammatory response was also observed 1 day after AT in both groups, the counts of reactive macrophages in both experimental conditions suggest decreased inflammation in the epidural stimulation group. Quantitative immunocytochemistry for choline acetyltransferase (ChAT) showed a significant decrease in the size and optical density of the efferent terminals 1 day after AT and a rebound at 14 days, suggesting depletion of the terminals followed by a long-term compensatory response. Such a synthesis recovery was significantly higher upon cortical stimulation. No significant correlation was found between ChAT optical density and size of the buttons in sham controls (SC) and ES/AT + 1day animals; however, significant negative correlations were shown in all other experimental conditions. Therefore, our comparative analysis suggests that cochleotopic cholinergic neurotransmission is also better preserved after multisession epidural stimulation.

scholarly journals Basic Research on Potential Application of Fire Detection by Measuring Fire Detection Tendency of Indoor Air Quality Measurement Factors

2020 ◽  
Vol 34 (1) ◽  
pp. 37-46
Author(s):  
Su-Gil Choi ◽  
Se-Young Jin ◽  
Sang-Min Park ◽  
Yeong-Jae Nam ◽  
Si-Kuk Kim
Keyword(s):  
Air Quality ◽  
Indoor Air Quality ◽  
Indoor Air ◽  
Potential Application ◽  
Quality Measurement ◽  
Fire Detection ◽  
Basic Research ◽  
Smoke Detector ◽  
Experimental Conditions ◽  
Fire Experiment

This is a basic research on potential application of fire detection by measuring fire detection tendency of indoor air quality measurement factors. In this study, operation experiment using smoke detector sensitivity tester and paper fire experiment specified in UL 268 standards were conducted to evaluate the fire detection tendency of indoor air quality measurement factors. Based on the cross-substitution of values measured in the paper fire experiment, PM10 (excluding average) and HCHO (excluding average and maximum) for the indoor air quality meter (IAQ); PM1.0, PM2.5, and PM10 for IAQ S2; and CO (excluding the average and maximum) for combustion gas analyzers showed consistent tendency despite changes in the measured values for smoke generation under all experimental conditions. In particular, PM10 and CO are considered the most applicable fire detection factors among the factors measured in the experiment.

scholarly journals Comparative Analysis of Rules in Five Leading Standards for Smoke Detectors Siting in the Presence of a Ceiling Irregularity

2017 ◽  
Vol 12 (2) ◽  
pp. 23-29 ◽  
Author(s):  
Milan Blagojević ◽  
Radoje Jevtić ◽  
Dejan Ristić
Keyword(s):  
Detection System ◽  
Fire Detection ◽  
Combustion Products ◽  
Point Of View ◽  
Smoke Detector ◽  
Main Question ◽  
European Norm ◽  
Length Width ◽  
Smoke Detectors ◽  
Formed Structure

Abstract Subdividing elements and different structures on the ceiling like beams or similar, significantly affect the location of the smoke detector, because they change the flow of combustion products. From point of view of fire detection system, designers it is very interesting how to arrange and distribute smoke detectors in applications when beams are formed structure like a “honeycomb” The European norm 54-14 is mandatory, but in practice, a main question appears: “Do we have the explanations detailed enough for all of the situations that could occur related to length, width and depth of honeycomb cells”? The main goal of this paper is to show the differences between the rules and the instructions in five standards: EN 54-14, VDE 0833-2, BS 5839-1, NPB 88, NFPA 72, and to find the best solution for various situations in practice.

ENZYME IMMUNOASSAY PROTOCOL OPTIMIZATION FOR T-2 TOXIN INDICATION

2020 ◽  
Vol 15 (4) ◽  
pp. 551-560
Author(s):  
N.N. Mishina ◽  
◽  
I.N. Shtyrov ◽  
E.I. Semenov ◽  
N.M. Vasilevskiy ◽  
...  
Keyword(s):  
Enzyme Immunoassay ◽  
Optical Density ◽  
Development Stage ◽  
Test System ◽  
Enzyme Linked Immunosorbent Assay ◽  
Experimental Conditions ◽  
First Case ◽  
Dependent Signal ◽  
Density Values ◽  
Enzyme Label

T-2 toxin is one of the most common and toxic trichothecene mycotoxins – secondary metabolites of molds that develop on cereals and some other crops. This article discusses the development stage of a test system for the determination of T-2 toxin based on enzyme-linked immunosorbent assay (ELISA), which uses an enzyme label – a conjugate of anti-rabbit goat antibodies with peroxidase. An important step in the creation of any ELISA-based test system is the preliminary titration of reaction components. The aim of the work was to determine the optimal concentration of the conjugate of antispecies antibodies in an indirectly competitive enzyme-linked immunosorbent enzyme immunoassay with the indication of T-2 toxin. A number of dilutions of the antivirus conjugate were examined: 1 : 1000; 1 : 2000; 1 : 3000; 1 : 4000; 1 : 5000; 1 : 7500; 1 : 10000; 1 : 12 500; 1 : 15,000; 1 : 17,500; 1 : 20,000; 1 : 30 000. In the ELISA staging protocol, calibration solutions of T-2 toxin at concentrations of 0.0 were used; 2.5; 5, 10, 20, 40, 80, 160 ng/ml and specific polyclonal rabbit antibodies to the T-2-BSA conjugate. Based on the average optical density values, calibration plots were constructed using the percentage of signal absorption from the zero standard. When evaluating the results of the study, the criterion for choosing the dilution of the conjugate of anti-species antibodies was considered the greatest, at which the best linearity of the grading plot is achieved and the level of its non-specific reaction with the zero standard would be the lowest. It was established that the optimal variants of dilutions of the conjugate of anti-species antibodies under the same experimental conditions tested were 1: 4000, 1 : 5000 and 1 : 12 500. Dose-dependent signal absorption was observed in all concentrations of anti-species antibodies. Dilutions of the conjugate of anti-species antibodies 1 : 1000–1 : 3000 and 1 : 17 500–1 : 30 000 were not taken into account, since the optical density of most wells was higher than the optimal boundaries in the first case (> 3.9) and lower in the second (< 0.4). Based on the foregoing, optimal dilution of the conjugate of anti-species antibodies was selected 1 : 12 500.

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