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The detection efficiency (DE) of the World Wide Lightning Location Network (WWLLN) is evaluated in Southeast Asia by comparing WWLLN data with the Earth Network Total Lightning Network (ENTLN) data taking into account time, distance, and peak‐current parameters. The performance of WWLLN is evaluated in the months of November and December in two different years (2020–2021). These periods are selected to assess the change (if any) in DE overtime and the inclusion of new stations. The strokes between the two networks were considered matched if they fell within a time criterion of 100 µs and a location difference of 25 km. Using this criterion, 5.2 × 106 WWLLN strokes were matched with ENTLN cloud‐to‐ground (CG) lightning strokes in November‐December 2020, resulting in a DE of 32.9%. Similarly, 4.6 × 106 WWLLN strokes were found to match in November‐December 2021, yielding a DE of 36.5%. Analysis of the peak‐currents reveals that DE is lowest (<10%) for a peak‐current below ±10 kA. However, for peak‐current exceeding ±50 kA, the DE increases to ∼60%. During November‐December 2021, WWLLN reported 38.95 × 106 lightning strokes globally; amongst them, Dhaka station detected 0.5 × 106 strokes, contributing to a 1.3% increase in the global DE. Dhaka station detects most lightning strokes within 8 × 103 km, which diminishes to zero after 10 × 103 km. The Dhaka station recorded a larger number of strokes at longer detection distances during midnight (22:00–02:00) than during noon (10:00–14:00). The results signify a positive impact of the Dhaka station on WWLLN's DE during the mentioned period. Plain Language Summary: This comprehensive study delves into the detection efficiency (DE) of the World‐Wide Lightning Location Network (WWLLN) in Southeast Asia, compared to Earth Network Total Lightning Network (ENTLN) data. A matching strategy is involved to identify the matched strokes between two networks. Spanning key intervals in November‐December 2020 and 2021, this study unveils significant results, highlighting an enhanced DE in WWLLN. This investigation delves into the repercussions of adding or removing detection stations. Establishing a WWLLN station in Dhaka emerges as significant, detecting over 0.5 × 106 lightning strokes and contributing to a notable global DE augmentation during the investigation period. This study identified a total count of cloud‐to‐ground (CG) lightning strokes in the specified region during the investigation period, with a WWLLN DE for CG strokes. The study unveils nuanced DE dynamics based on peak‐currents, showing the lowest detection efficiency below for lower peak‐currents and a remarkable surpass for higher peak‐currents value. Key Points: In Southeast Asia, the detection efficiency of World Wide Lightning Location Network (WWLLN) improved by 3.6% in 1 year (2020–2021)In the region of interest, the detection efficiency of the WWLLN is lower than 10% for 10 kA peak‐currents but surpasses 60% for 50 kADuring November–December 2021, WWLLN Dhaka station detected 500 × 103 lightning strokes, contributing to a 1.3% increase in global detection efficiency [ABSTRACT FROM AUTHOR]

Range tests play a critical role in designing acoustic telemetry studies, guiding equipment configuration, deployment techniques, and the analysis of animal movement data. These studies often strive to capture the effects of environmental variation on detection efficiency over time but are frequently limited in spatial and temporal scale. This could lead to disparities between test results and the circumstances encountered during animal tracking studies. In this study, we evaluated detection range and efficiency at two distinct spatial and temporal scales in a dynamic intertidal ecosystem. Two range tests were conducted, the first being a small-scale study using 6 receivers deployed over 1 month. Using modern acoustic receivers with built-in transmitters and environmental sensors, we then conducted a large-scale range test with 22 receiver stations over a full year to approximate the area and duration of a typical animal movement study. Differences in detection range between the two studies occurred as a result of environmental variation and tag power output, with midpoint ranges estimated as 123 m (small scale, low power), 149 m (small scale, high power) and 311 m (large scale, very high power). At both scales, wind speed emerged as the most influential factor explaining temporal variation in predicted detection efficiency. However, this effect was modulated by wind direction which varied as a result of land sheltering and fetch between the two study scales. At the small scale, detection efficiency decreased with winds from the south and east, while at the large scale, northern and westerly winds were most detrimental. Water temperature had a positive effect on predicted detection efficiency at both scales, while relative water level was positive at the small scale and negative at the large scale. Additional factors, including precipitation and Topographic Position Index, were found to influence detection efficiency at a large scale. Moreover, sensors associated with receivers in the larger array revealed the significant influences of receiver tilt and ambient noise. These discrepancies in the outcomes of the two studies underscore the critical role of scale in range test design and emphasize the need for long-term, in situ range testing at relevant spatial scales. [ABSTRACT FROM AUTHOR]

Abstract Range tests play a critical role in designing acoustic telemetry studies, guiding equipment configuration, deployment techniques, and the analysis of animal movement data. These studies often strive to capture the effects of environmental variation on detection efficiency over time but are frequently limited in spatial and temporal scale. This could lead to disparities between test results and the circumstances encountered during animal tracking studies. In this study, we evaluated detection range and efficiency at two distinct spatial and temporal scales in a dynamic intertidal ecosystem. Two range tests were conducted, the first being a small-scale study using 6 receivers deployed over 1 month. Using modern acoustic receivers with built-in transmitters and environmental sensors, we then conducted a large-scale range test with 22 receiver stations over a full year to approximate the area and duration of a typical animal movement study. Differences in detection range between the two studies occurred as a result of environmental variation and tag power output, with midpoint ranges estimated as 123 m (small scale, low power), 149 m (small scale, high power) and 311 m (large scale, very high power). At both scales, wind speed emerged as the most influential factor explaining temporal variation in predicted detection efficiency. However, this effect was modulated by wind direction which varied as a result of land sheltering and fetch between the two study scales. At the small scale, detection efficiency decreased with winds from the south and east, while at the large scale, northern and westerly winds were most detrimental. Water temperature had a positive effect on predicted detection efficiency at both scales, while relative water level was positive at the small scale and negative at the large scale. Additional factors, including precipitation and Topographic Position Index, were found to influence detection efficiency at a large scale. Moreover, sensors associated with receivers in the larger array revealed the significant influences of receiver tilt and ambient noise. These discrepancies in the outcomes of the two studies underscore the critical role of scale in range test design and emphasize the need for long-term, in situ range testing at relevant spatial scales.

Speckles are ubiquitous phenomena associated with multi‐spatial‐mode optics, which may reduce detection efficiency and induce modal noise if the photoresponse of the detector is polarization‐dependent. Thus far, they limit the performance of superconducting nanowire single‐photon detectors (SNSPDs) coupled with multimode optical fibers (MMF). To solve this problem, here, it is shown that SNSPDs patterned into the fractal geometry is insensitive to speckles and generates minimal modal noise that would otherwise be induced by the polarization‐dependent local device efficiency of the meander and spiral SNSPDs. Using this advantageous property of the fractal SNSPDs, 78±2%$78 \pm 2\%$ system detection efficiency at the wavelength of 1530 nm and 42‐ps timing jitter is demonstrated when we couple a fractal SNSPD with 50‐micrometer‐core, step‐index MMF. This work not only demonstrates a scheme to achieving high system detection efficiency for MMF‐coupled SNSPDs that can be used in many applications, but also provides insight on how engineered nanostructures of photodetectors can reduce modal noise when detecting light from multiple spatial modes. [ABSTRACT FROM AUTHOR]

Camera trap model and setup choice can significantly affect data collection. This study investigated standard-angle Reconyx and wide-angle Swift camera traps in different setups and how the choice of equipment influenced detection and individual identification of the chuditch (Dasyurus geoffroii). Camera models were placed side-by-side in four setups: (i) single and (ii) paired camera traps 30 cm above ground; and single cameras (iii) 1 m and (iv) 2 m above ground, with a lure (tuna oil) in the centre of all setups. Swifts had a higher Detection probability than Reconyx, although the number of detections with identified individuals did not significantly differ between camera models. The 30 cm paired camera setups had the highest Detection and Identification probabilities for both camera models, with both probabilities decreasing as cameras were positioned higher. Camera model and setup choice are important in obtaining detection and identification data, and should be considered when planning studies and interpreting results. Many wildlife studies using camera traps require a high probability of animal detection and, depending on study aim, the ability to identify individuals. For a cryptic species this can be difficult, but testing different setups for camera traps improves both detection and individual identification. In the case of the chuditch, a medium-sized marsupial carnivore, paired cameras at 30 cm height had the best Detection and Identification probability. This setup can be used in a variety of chuditch studies to gather more useable data and would increase the reliability of results such as population density estimates. Photograph by Melissa Taylor. [ABSTRACT FROM AUTHOR]

BackgroundThe very small-angle neutron scattering (VSANS) spectrometer is currently being constructed at the China spallation neutron source (CSNS). The neutron detector plays a key role in meeting the detection requirements of the spectrometer.PurposeThis study aims to achieve accurate measurement of neutron diffraction in the small angle scattering mode which requires the position resolution of the neutron detector to be ≤2 mm, and the detection efficiency to be ≥60%@0.4 nm.MethodsA large-area position-sensitive neutron scintillator detector mainly composed of 6LiF/ZnS(Ag) scintillation screen, wavelength shift fiber (WLSF), and a silicon photomultiplier (SiPM) was designed and developed to achieve high efficiency and high-resolution real-time detection of thermal neutrons. The optical transmission performance of the 0.5-mm-diameter wavelength shift fiber was investigated in detail. The gain and the thermal noise characteristics of various SiPMs were examined. Finally, a 300 mm×300 mm engineering prototype of the detector was developed and tested by experiments. The detection efficiency was calculated with comparison of the incident neutron counts of the stander 3He tube whilst the detector's position resolution was tested using a boron-doped aluminum plate with a narrow slit bearing the label 'CSNS'.ResultsThe neutron beam test results show that the position resolution of the detector is 1.2 mm×1.2 mm and that the neutron detection efficiency is (61.8±0.2)%@0.4 nm.ConclusionsThe high-resolution neutron scintillator detector developed in this study satisfies the engineering design target, and meets the neutron scintillator detector meets the neutron diffraction measurement needs for the VSANS spectrometer of the CSNS.

In order to accurately measure the path of the incident particles in front of the target at the CSR outer target terminal, multiple sets of small cell multi-wire drift chamber detectors were developed with a drift cell of 5 mm. The sensitive area of this detector is 80 mm×80 mm, each set of detector includes x, x', y and y' 4 detection electrode surfaces, 2 sets of detection electrode surface wires are perpendicular to each other, and the same direction detection electrode surface wires are misaligned and distributed for providing left and right resolution, the misalignment distance of 2.5 mm for half drift cell, each electrode surface leads to 16 anode wire signals. The front-end electronics uses an amplifier based on the SFE16 chip, a 16-way ASIC signal processing developed by Saclay, France, whose functions include charge-sensitive amplification, shaping and signal screening, and outputting the TOT signal. The TOT signal is input to a data acquisition card based on the HPTDC chip developed by CERN, which records the rising and falling edge times of the TOT signal. The T0 plastic flash detector, placed in front of the drift chamber, provides the onset moment of the incident particles. By subtracting the TOT signal front from T0, the drift time of the incident particle traces in the multi-wire drift chamber can be obtained. The particles incident to the secondary target are physically concerned as heavy particles, so 2 sets of small cell multi-wire drift chambers were used to test the 16O beam position at 400 MeV/u. During the test, the operating gas of the detector was Ar(80%)+CO2(20%), the anode wire voltage was +900 V, and both the field and cathode wires were grounded. After acquiring the test data for data processing, the R-T curves were obtained by simulation with interpolation correction, and the path traces were reconstructed by least squares method. After the data processing, the path residual of the single-layer electrode fitted to obtain the position resolution is 105.9 μm, and the path residual is defined as the difference between the distance from each hitting wire to the fitted straight line and the drift distance measured in each layer. The detection efficiency is 99.3%, and the detection efficiency is defined as the ratio of the count of the multi-wire drift chamber to the count of the plastic flash detector after deducting the background. The above indexes can meet the requirements of most of the nuclear physics experiments of the CSR external target terminal for the localization of the reaction target at this stage.

Aviation soot constitutes a significant threat to human well-being, underscoring the critical importance of accurate measurements. The condensation particle counter (CPC) is the primary instrument for quantifying aviation soot, with detection efficiency being a crucial parameter. The properties of small particles and the symmetry of their growth pathways are closely related to the detection efficiency of the CPC. In laboratory environments, sodium chloride is conventionally utilized to calibrate the CPC's detection efficiency. However, aviation soot exhibits distinctive morphological characteristics compared to the calibration particles, leading to detection efficiencies obtained from calibration particles that may not be applicable to aviation soot. To address this issue, a quantitative study was performed to explore the detection efficiency deviations between aviation soot and calibration particles. The experiment initially utilized a differential mobility analyzer to size select the two types of polydisperse particles into monodisperse particles. Subsequently, measurements of the separated particles were performed using the TSI Corporation's aerosol electrometer and a rigorously validated CPC (BH-CPC). These allowed for determining the detection efficiency deviation in the BH-CPC for the two types of particles at different particle sizes. Furthermore, the influence of the operating temperature of the BH-CPC on this detection efficiency deviation was investigated. The experimental results indicate a significant detection efficiency deviation between aviation soot and sodium chloride. In the range of 10–40 nm, the absolute detection efficiency deviation can reach a maximum of 0.15, and the relative deviation can reach a maximum of 0.75. And this detection efficiency deviation can be reduced by establishing a relevant relationship between the detection efficiency of the operating temperature and the calibration temperature. Compared to the saturated segment calibration temperature of 50 °C, the aviation soot detection efficiency is closer to the sodium chloride detection efficiency at the calibration temperature of 50 °C when the saturated segment operates at a temperature of 45 °C. These studies provide crucial theoretical guidance for enhancing the precision of aviation soot emission detection and establish a foundation for future research in monitoring and controlling soot emissions within the aviation sector. [ABSTRACT FROM AUTHOR]

The k0-INRIM is a software implemented at the Italian Metrology Institute (INRIM) to aid users elaborating data to obtain results including uncertainty budgets for Neutron Activation Analysis (NAA). The code relies on the efficiency evaluation based on an experimental characterization of the gamma detection system to calculate efficiency-based corrections. In order to validate the models adopted for these corrections in most demanding experimental conditions, an experiment is performed to collect data from point-like and extended-sources counted far from and near to the end-cap of two gamma detectors having different relative efficiency. The results comparing the experimentally evaluated and the calculated corrections are reported with detailed uncertainty estimation. [ABSTRACT FROM AUTHOR]

Traditional fire assay analysis has always used manual work methods, with high labor intensity, low efficiency, and high occupational health and safety risks. The developed automated fire assay detection system consists of an automated batching system, automated mixing and filling system, automated melting system, automated cupellation system, and automated gold distribution system, corresponding to 5 analysis steps of batching, mixing, melting, cupellation, and gold distribution. The system realizes the automated detection mode of fire assay, with accurate and reliable detection results, consistent with the manual detection results, and a unified and stable operation process, free from subjective factors of personnel. After being put into production and application, the system greatly improves the detection efficiency, increasing it by more than 167 percentage points compared with manual mode, reducing labor intensity, and ensuring the occupational health and safety of personnel. The automated fire assay detection system has a high value for promotion and application. [ABSTRACT FROM AUTHOR]

This study investigated the influence of cognitive interference on the detectability of concealed information in a reaction time (RT)‐based concealed information test (CIT). The classical RT‐based CIT was modified to interfere with response preparation, hypothesizing that this interference would enhance detection efficiency. A total of 120 participants were randomly assigned as "guilty" or "innocent" and were instructed to deny any knowledge related to a mock crime. The results revealed that guilty participants exhibited significantly longer RTs for probes than for irrelevant stimuli in both the classical and modified‐CIT conditions (aka CIT effect). In contrast, innocent participants showed no difference in RTs between the probe and irrelevant stimuli under either condition. Furthermore, the modified‐CIT yielded significantly higher detection efficiency than the classical‐CIT. These findings signify promising advancements in the application of cognitive interventions in deception detection methodologies. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Germanium crystals have a dead layer that causes a decrease in efficiency since the layer is not useful for detection but strongly attenuates photons. The thickness of this inactive layer is not well known due to the existence of a transition zone where photons are increasingly absorbed. Therefore, using data provided by manufacturers in the detector simulation model, some strong discrepancies appear by changing the dead layer. Investigations into the Ge detector response functions for gamma rays have been conducted using straightforward physical mechanisms implemented by Monte Carlo simulations. The detector response function feature's most probable interaction mechanisms are described. The Monte Carlo method is applied to simulate the calibration of a HPGe detector in order to determine the total inactive germanium layer thickness and the active volume that is needed in order to study the response function for both types of detectors. Results indicated a strong impact of dead layer variations on the response function of the simulated detectors.

Due to the shortage of 3He gas and the rapidly increasing price, it is urgent to seek a new neutron detector to replace 3He gas detector. Scintillator based on 6LiF/ZnS(Ag) is an ideal material for thermal neutron detection because of its large neutron cross section, high detection efficiency and strong γ suppression. The neutron detector model was established using Monte Carlo procedure MCNP5 in this work. The neutron detection efficiency was calculated under different mass ratio and thickness parameters. The simulation results show that the thermal neutron detection efficiency improves with the increase of detector thickness. This means that one can use laminated construction to increase neutron efficiency in subsequent detector design. The simulation results also show that the thermal neutron detection efficiency improves with the increase of the mass ratio of 6LiF and ZnS(Ag) (the value increases from 1∶6 to 1∶2 in this work). 6LiF/ZnS(Ag) detectors in five different thicknesses (100, 200, 250, 300, 400 μm) and two mass ratios with 1∶3 and 1∶4 were manufactured. A 252Cf neutron source and a 60Co γ source were used to measure the performance of detectors. Detection efficiency measured results show that the detectors with mass ratio of 1∶3 and 1∶4 have higher detection efficiency of thermal neutrons. They both can reach 30% or more. However, the detector with mass ratio of 1∶3 is better than that of 1∶4. The detector with 400 μm thickness has higher thermal neutron detection efficiency. γ sensitivity measured results show that the detector has a strong ability to inhibit γ signal. In certain threshold voltage condition, the γ sensitivity can reach 1×10-7. There is no significant difference in γ sensitivity of detectors with two mass ratios of 1∶3 and 1∶4. To consider neutron detection efficiency and γ sensitivity comprehensively, the threshold voltage setting in 45 mV was appropriate under the current detector conditions. In general, the detector developed in this paper has a good property and it is equivalent to the international level of similar products.

Copyright of Chinese Journal of Refrigeration Technology is the property of Shanghai Society of Refrigeration and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A validation study of the Geostationary Lightning Mapper (GLM) on board the Geostationary Operational Environmental Satellite 16 (GOES‐16) was done using a ground‐based lightning mapping array (LMA) deployed as part of the Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign in Argentina. GLM detected lightning with 74.6% efficiency over 61 thunderstorm days in December 2018 through April 2019. However, GLM detection efficiency (DE) was negatively correlated (r = −0.49) with LMA flash rate. GLM DE also was negatively correlated with LMA flash altitude (r = −0.24), reflecting the influence of multiple competing trends. GLM DE was positively correlated (r = 0.27) with number of LMA sources in a flash, indicating improved DE for larger flashes. During periods with anomalously electrified storms, GLM DE was reduced to 50.9%. Statistics were found to be sensitive to analysis criteria, but most of the above trends remained consistent regardless of specific criteria. Because the methodology allowed a GLM flash to match more than one LMA flash, actual GLM flash rate was a factor of 2.9 lower than the LMA flash rate, and this ratio grew larger as LMA flash rate increased. A sensitivity study examined the impact of improved DE for smaller flashes; that is, an improved sensor (or algorithm) that was better able to detect and distinguish between separate small lightning flashes. The results showed improved correlation with LMA flash rates, as well as improved ability to identify lightning jumps associated with intensifying convection. Plain Language Summary: Based on a comparison with a ground‐based, three‐dimensional lightning detection system in Argentina, the Geostationary Lightning Mapper (GLM) on board the Geostationary Operational Environmental Satellite 16 (GOES‐16) detects lightning with nearly 75% efficiency, which meets its requirements. However, that detection efficiency decreases a lot when thunderstorms produce a lot of lightning at once, or small lightning flashes, or when lightning occurs deeper in the cloud where it is more difficult for the optical pulse to make its way to cloud top. This makes GLM somewhat less useful during the most intense part of a storm's life. However, if GLM or a similar sensor could be made more sensitive, either with improved hardware design or better data processing, then it would become more useful in intense storms. Key Points: The Geostationary Lightning Mapper detected lightning with overall 75% efficiency relative to a ground network in ArgentinaDetection efficiency depended significantly on day/night, and on flash rate, size, altitude, and the presence of anomalous lightningAn improved sensor that could better detect and distinguish between small flashes would provide more information about storm evolution [ABSTRACT FROM AUTHOR]

Germanium crystals have a dead layer that causes a decrease in efficiency since the layer is not useful for detection but strongly attenuates photons. The thickness of this inactive layer is not well known due to the existence of a transition zone where photons are increasingly absorbed. Therefore, using data provided by manufacturers in the detector simulation model, some strong discrepancies appear by changing the dead layer. Investigations into the Ge detector response functions for gamma rays have been conducted using straightforward physical mechanisms implemented by Monte Carlo simulations. The detector response function feature's most probable interaction mechanisms are described. The Monte Carlo method is applied to simulate the calibration of a HPGe detector in order to determine the total inactive germanium layer thickness and the active volume that is needed in order to study the response function for both types of detectors. Results indicated a strong impact of dead layer variations on the response function of the simulated detectors. [ABSTRACT FROM AUTHOR]

We evaluated the detection efficiency and location accuracy of lightning discharges in Japan using Blitzortung.org, a volunteer-based network for locating lightning discharges from sferics measured by very low frequency (VLF) electromagnetic receivers that have been deployed worldwide in recent years. A comparison of the flash rate (the detected lightning rate per area and period) from Blitzortung.org with that from the satellite-based OTD/LIS and the ground-based World Wide Lightning Location Network (WWLLN) observations showed that Blitzortung.org clearly observed intense lightning activity in and around the Kanto area, including Tokyo, in summer, which is typical of Japanese lightning activity. However, it did not clearly observe lightning activity in and around the Nansei Islands, including Okinawa. Conversely, Blitzortung.org observed winter lightning activity in the Hokuriku area and off the Kanto. In addition, event studies have compared the detection efficiency and location accuracy of Blitzortung.org with those of the Japanese Lightning Location Network (JLDN) to infer their absolute values. The latest detection efficiency of Blitzortung.org in the Kanto area was estimated at roughly 90%. The mean location accuracy was estimated at up to 5.6 km. [ABSTRACT FROM AUTHOR]

In order to study the detection performance of the Advanced Direction Time Lightning Detection System (ADTD) over mainland China, the relationship between the detection efficiency (DE) and distance for ADTD sensor is analyzed using lightning location data by ADTD during 2014–2020, which fits well with the probability density function of the Gamma distribution. The DE and location accuracy of ADTD across China are hereafter evaluated according to the constructed probability density function. The results show that the DE of a single sensor first increases rapidly and then decreases slowly with the increase of the detection distance, and the model constructed based on the probability density function of Gamma distribution can explain this relationship well. In the regions with dense sensors such as central and eastern China, the DE of ADTD can reach 95%, with the majority of regions having lower location errors (less than 1,000 m). While, in the areas where sensors are sparse such as the Qinghai-Tibet Plateau and at the edge of ADTD, the DE of ADTD is less than 90% (in some areas it is even lower than 50%), and the location error greater than 1,000 m. In general, ADTD can accurately detect cloud-to-ground lightning events in most areas of China, but its accuracy is limited in some areas due to sparse sensors and instrument parameter settings.

ObjectiveImproving the detection capability and efficiency of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA specimens is very important for the prevention and control of the outbreak of Coronavirus disease 2019 (COVID-19). In this study, we evaluated the detection capability and efficiency of two outbreaks of COVID-19 before and after the process re-engineering in April and July 2022.MethodsThis retrospective cross-sectional study involved 359,845 SARS-CoV-2 RNA specimens 2 weeks before and 2 weeks after the two outbreaks of COVID-19 in April and July. The number, transportation time and detection time of specimens, and the number of reports of more than 24 h were analyzed by SPSS software.ResultsWhile 16.84% of people chose nasopharyngeal swabs (NPS) specimens, 83.16% chose oropharyngeal swabs (OPS) specimens to detect SARS-CoV-2 RNA. There were significant upward trends in the percentage of 10 sample pooling (P-10) from April before process re-engineering to July after process re-engineering (p

Fish monitoring gears rarely capture all available fish, an inherent bias in monitoring programs referred to as catchability. Catchability is a source of bias that can be affected by numerous aspects of gear deployment (e.g., deployment speed, mesh size, and avoidance behavior). Thus, care must be taken when multiple surveys—especially those using different sampling methods—are combined to answer spatio-temporal questions about population and community dynamics. We assessed relative catchability differences among four long-term fish monitoring surveys from the San Francisco Estuary: the Bay Study Otter Trawl (BSOT), the Bay Study Midwater Trawl (BSMT), the Fall Midwater Trawl (FMWT), and the Suisun Marsh Otter Trawl (SMOT). We used generalized additive models with a spatio-temporal smoother and survey as a fixed effect to predict gear-specific estimates of catch for 45 different fish species within large and small size classes. We used estimates of the fixed effect coefficients for each survey (e.g., BSOT) relative to the reference gear (FMWT) to develop relative measures of catchability among taxa, surveys, and fish-size classes, termed the catch-ratio. We found higher relative catchability of 27%, 22%, and 57% of fish species in large size classes from the FMWT than in the BSMT, BSOT, or SMOT, respectively. In the small size class, relative catchability was higher in the FMWT than the BSMT, BSOT, or SMOT for 50%, 18%, and 25% of fish species, respectively. As expected, relative catchability of demersal species was higher in the otter trawls (BSOT, SMOT) while relative catchability of pelagic species was higher in the midwater trawls (FMWT, BSMT). Our results demonstrate that catchability is a source of bias among monitoring efforts within the San Francisco Estuary, and assuming equal catchability among surveys, species, and size classes could result in significant bias when describing spatio-temporal patterns in catch if ignored.

Objective To study the detection efficiency of trio full sibling with another known full sibling reference added under different number of autosomal STR typing systems. Methods Based on 43 detection systems consisting of 13 to 55 representative autosomal STR loci，10 000 true families （full sibling group） and 10 000 false families （unrelated individual group） were randomly simulated. The full sibling index （FSI） was calculated based on the method of family reconstruction. The cumulative sibling relationship index （CFSI） of 0.000 1 and 10 000 were used as the evaluation thresholds, and the detection efficiency parameters were calculated and compared with the identification of the duo full sibling testing. Results With the increasing number of STR loci， the error rate and inability of judgement rate gradually decreased; the sensitivity， specificity, correct rate of judgment and other parameters gradually increased, and the system efficiency gradually improved. Under the same detection system， trio full sibling testing showed higher sensitivity， specificity， system efficiency and lower inability of judgement rate compared with duo full sibling testing. When the system efficiency was higher than 0.85 and inability of judgement rate was less than 0.01%， at least 20 STRs should be detected for trio full sibling testing， which was less than 29 STRs required by duo full sibling testing. Conclusion The detection efficiency of trio full sibling testing is superior to that of duo full sibling testing with the same detection system， which is an effective identification scheme for laboratories with inadequate detection systems or for materials with limited conditions.

Copyright of Laser Technology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The results of studies of the characteristics of the prototype of the scintillation time-of-flight hodoscope 71 cm long are presented. Prototype testing using a 90Sr + 90Y radioactive source showed that the coordinate resolution and detection efficiency depend on the source position on the work surface. The best coordinate resolution and the highest detection efficiency were found at the module center as σx ≈ 1.2 cm and ε ≈ 9%, respectively. [ABSTRACT FROM AUTHOR]

An area has been designated for demonstrating the utility of marine hydrokinetic turbines in Minas Passage, Bay of Fundy. Marine renewable energy may be useful for the transition from carbon-based energy sources, but there is concern for the safety of fish that might encounter turbines. Acoustic receivers that detect signals from acoustically tagged fish that pass through the tidal demonstration area and the detection efficiency of tag signals might be used to estimate the likelihood of fish encountering marine hydrokinetic turbines. The method requires that tagged fish passing through the development area will be reliably detected by a receiver array. The present research tests the reliability with which passing tags are detected by suspending tags beneath GPS-tracked drifters. Drifters carrying high residency Innovasea tags that transmitted every 2 s were usually detected by the receiver array even in fast currents during spring tides but pulse-position modulation tags were inadequate. Sometimes very few high residency tag signals were detected when fast tidal currents swept a drifter through the receiver array, so increasing the transmission interval degrades performance at the tidal energy development area. High residency tags suspended close to the sea surface were slightly less likely to be detected if they passed by during calm conditions. Previously measured detection efficiencies were found to slightly overestimate the chances of a high residency tag carried by a drifter being detected as it passed by a receiver. This works elucidates the effectiveness with which acoustically tagged fish are detected in fast, highly turbulent tidal currents and informs the application of detection efficiency measurements to calculate the probability that fish encounter a marine hydrokinetic turbine. [ABSTRACT FROM AUTHOR]

Abstract A validation study of the Geostationary Lightning Mapper (GLM) on board the Geostationary Operational Environmental Satellite 16 (GOES‐16) was done using a ground‐based lightning mapping array (LMA) deployed as part of the Remote sensing of Electrification, Lightning, And Mesoscale/microscale Processes with Adaptive Ground Observations (RELAMPAGO) field campaign in Argentina. GLM detected lightning with 74.6% efficiency over 61 thunderstorm days in December 2018 through April 2019. However, GLM detection efficiency (DE) was negatively correlated (r = −0.49) with LMA flash rate. GLM DE also was negatively correlated with LMA flash altitude (r = −0.24), reflecting the influence of multiple competing trends. GLM DE was positively correlated (r = 0.27) with number of LMA sources in a flash, indicating improved DE for larger flashes. During periods with anomalously electrified storms, GLM DE was reduced to 50.9%. Statistics were found to be sensitive to analysis criteria, but most of the above trends remained consistent regardless of specific criteria. Because the methodology allowed a GLM flash to match more than one LMA flash, actual GLM flash rate was a factor of 2.9 lower than the LMA flash rate, and this ratio grew larger as LMA flash rate increased. A sensitivity study examined the impact of improved DE for smaller flashes; that is, an improved sensor (or algorithm) that was better able to detect and distinguish between separate small lightning flashes. The results showed improved correlation with LMA flash rates, as well as improved ability to identify lightning jumps associated with intensifying convection.

The hyperspectral full-waveform LiDAR (HSL) system based on the supercontinuum laser can obtain spatial and spectral information of the target synchronously and outperform traditional LiDAR or imaging spectrometers in target classification and other applications. However, low detection efficiency caused by the detection of useless background points (ULBG) hinders its practical applications, especially when the target is small compared with the large field of view (FOV) of the HSL system. A novel vision-aided hyperspectral full-waveform LiDAR system (V-HSL) was proposed to solve the problem and improve detection efficiency. First, we established the framework and developed preliminary algorithms for the V-HSL system. Next, we experimentally compared the performance of the V-HSL system with the HSL system. The results revealed that the proposed V-HSL system could reduce the detection of ULBG points and improve detection efficiency with enhanced detection performance. The V-HSL system is a promising development direction, and the study results will help researchers and engineers develop and optimize their design of the HSL system and ensure high detection efficiency of spatial and spectral information of the target. [ABSTRACT FROM AUTHOR]

The space-based gamma-ray telescope must effectively separate photons from charged particles of instrumental background and cosmic rays. It requires that the anticoincidence system of the telescope must have high detection efficiency, large dynamic range and good enough energy and time resolution for charged particles. The main results obtained using 246 MeV secondary positron beam of synchrotron S-25R "PAKHRA" of Lebedev Physical Institute with prototype of system of anticoincidence detectors of space-based gamma-ray telescope GAMMA-400 are presented. The amplitude resolution, time resolution and charged particles detection efficiency are adduced. All measurements were performed using "fast" output of silicon photomultipliers of prototype scintillation detectors sensors. Fractal dimensions of temporal profiles registered during measurements using positron beam and atmospheric muons are discussed. [ABSTRACT FROM AUTHOR]

Aviation soot constitutes a significant threat to human well-being, underscoring the critical importance of accurate measurements. The condensation particle counter (CPC) is the primary instrument for quantifying aviation soot, with detection efficiency being a crucial parameter. The properties of small particles and the symmetry of their growth pathways are closely related to the detection efficiency of the CPC. In laboratory environments, sodium chloride is conventionally utilized to calibrate the CPC’s detection efficiency. However, aviation soot exhibits distinctive morphological characteristics compared to the calibration particles, leading to detection efficiencies obtained from calibration particles that may not be applicable to aviation soot. To address this issue, a quantitative study was performed to explore the detection efficiency deviations between aviation soot and calibration particles. The experiment initially utilized a differential mobility analyzer to size select the two types of polydisperse particles into monodisperse particles. Subsequently, measurements of the separated particles were performed using the TSI Corporation’s aerosol electrometer and a rigorously validated CPC (BH-CPC). These allowed for determining the detection efficiency deviation in the BH-CPC for the two types of particles at different particle sizes. Furthermore, the influence of the operating temperature of the BH-CPC on this detection efficiency deviation was investigated. The experimental results indicate a significant detection efficiency deviation between aviation soot and sodium chloride. In the range of 10–40 nm, the absolute detection efficiency deviation can reach a maximum of 0.15, and the relative deviation can reach a maximum of 0.75. And this detection efficiency deviation can be reduced by establishing a relevant relationship between the detection efficiency of the operating temperature and the calibration temperature. Compared to the saturated segment calibration temperature of 50 °C, the aviation soot detection efficiency is closer to the sodium chloride detection efficiency at the calibration temperature of 50 °C when the saturated segment operates at a temperature of 45 °C. These studies provide crucial theoretical guidance for enhancing the precision of aviation soot emission detection and establish a foundation for future research in monitoring and controlling soot emissions within the aviation sector.

Copyright of Journal of Forensic Medicine / Fayixue Zazhi is the property of Journal of Forensic Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of World Nuclear Geoscience is the property of World Nuclear Geoscience Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Semidiurnal tidal currents can exceed 5 ms − 1 in Minas Passage, Bay of Fundy, where a tidal energy demonstration area has been designated to generate electricity using marine hydrokinetic turbines. The risk of harmful fish–turbine interaction cannot be dismissed for either migratory or local fish populations. Individuals belonging to several fish populations were acoustically tagged and monitored by using acoustic receivers moored within the Minas Passage. Detection efficiency ρ is required as the first step to estimate the probability of fish–turbine encounter. Moored Innovasea HR2 receivers and high-residency (HR) tags were used to obtain detection efficiency ρ as a function of range and current speed, for near-seafloor signal paths within the tidal energy development area. Strong tidal currents moved moorings, so HR tag signals and their reflections from the sea surface were used to measure ranges from tags to receivers. HR2 self-signals that reflected off the sea surface showed which moorings were displaced to lower and higher levels on the seafloor. Some of the range testing paths had anomalously low ρ , which might be attributed to variable bathymetry blocking the line-of-sight signal path. Clear and blocked signal paths accord with mooring levels. The application of ρ is demonstrated for the calculation of abundance, effective detection range, and detection-positive intervals. High-residency signals were better detected than pulse position modulation (PPM) signals. Providing that the presently obtained ρ applies to tagged fish that swim higher in the water column, there is a reasonable prospect that probability of fish–turbine encounter can be estimated by monitoring fish that carry HR tags. [ABSTRACT FROM AUTHOR]

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It is critical to accurately align a quantum photon detector such as a superconducting transition-edge sensor (TES) to an optical fiber in order to optimize its detection efficiency. Conventionally, such alignment requires advanced infrared imaging equipment or sophisticated microfabrication. We introduce a novel technique based on the simple idea of reflected wave intensity measurement which allows to determine the boundary of the sensor and align it accurately with the fiber. By routing a light wave through an optical fiber for normal incidence on the surface of the sensor chip, and separating the reflected wave coupled back into the fiber from the input signal with a circulator, we can observe the variation in the reflected wave intensity when the beam spot of the fiber crosses the boundary between the sensor and substrate that have different reflectivity, and adjust the position of the fiber such that its output falls on the sensor. We evaluate quantitatively the precision of our alignment method, as well as the conditions that must be met to avoid photon loss caused by light beam divergence. After demonstrating the working principle of our scheme and verifying the alignment result experimentally, we employ it for efficient input signal coupling to a TES device, which is used for photon-number-resolving measurement to showcase the successful application of our alignment method in practice. Relying on only ordinary and widely used optical elements that are easy to operate and low in cost, our solution is much less demanding than conventional methods. Dramatically easier to implement and not restricted by the detection mechanism of the sensor, it is accessible to a much broader community. [ABSTRACT FROM AUTHOR]

Automated test case generation technology aims to reduce test costs.Compared with manual test generation,it has higher test efficiency.Most existing testing tools treat all files in the software equally,but in fact,files with defects account for only a small part of the whole code.Therefore,if testers can detect files that are more prone to defects,they can greatly save testing resources.To solve the above problems,this paper designs a predictive guidance test tool AutoUnit,which is based on active learning.We first predict the defect files in the whole file pool to be detected.Next,we use the detection tool to detect the most “suspicious” files.Then we feed back the actual detection results to the prediction model and update the model to enter the next round of prediction.In addition,when the total number of defective files is unknown,AutoUnit can stop in time by setting diffe-rent target recall rates.It can predict the total number of defective files according to the tested files,calculate the current recall rate,judge whether to stop predict guidance and ensure testing efficiency.Experimental analysis shows that when the same number of defect files are tested,the shortest time and the longest time taken by AutoUnit is 70.9% and 80.7% of the current mainstream testing tools,respectively.When the total number of defective files is unknown and the target recall rate is set to 95%,compared with the latest version of Evosuite,AutoUnit only needs to check 29.7% of the source code files to achieve the same detection level,and its test time is only 34.6% of Evosuite,the cost of testing is greatly reduced.Experimental results show that the method effectively improves the efficiency of test.

In the present work, alpha particles detection efficiency of polycarbonate detector (PC) is calculated using Geant4 simulation toolkit. A PC detector with 250 µm thickness and dimension of 2.5 × 2.5 cm2 is considered. Assuming the passage of alpha particles of an 241Am source through brass collimators with different lengths, various alpha energies ranging from 0.2 to 2.5 MeV are modeled. Also, an etching layer of 6 µm related to a given electrochemical etching process as well as a threshold stopping power of 240 keV µm-1 required for forming the tracks are used as the input data. The detection efficiency is determined as the ratio of registered tracks per unit area to the number of alpha particles reaching the PC detector surface. To validate the simulation, the results are compared with the experimental data reported in the literature. It is found that the both results agree well within a maximum variation of 10%.

In this study, we used the integral method of the probability density function to evaluate the detection efficiency of an inhomogeneous iodine cartridge source by fitting the function relationship between the efficiency of the 131I γ-ray and the height of the disk source from the detector. We constructed a mathematical model by combining the efficiency ratio of the positive and negative placement, K, and the distribution parameter, α, to determine the activity of 131I in the iodine cartridge. To verify this method, we analyzed the inhomogeneous iodine cartridge samples obtained from a gaseous iodine collection experiment. The average deviation of the total activity of 131I, calculated by using 131I γ-ray (364.48 keV), in the iodine cartridge between our method and the homogeneous iodine cartridge source obtained by employing disassembly-stirring-backfilling was 5.71%, and the maximum deviation was 8.54%. The results showed that the disk source calibration method of the probability density function can be used to determine the detection efficiency of inhomogeneous iodine cartridges, thereby providing a feasible method for monitoring gaseous iodine.

The data of neutron capture reaction cross section are very important basic data in the research fields of advanced nuclear energy development and nuclear astrophysics. In order to accurately measure the cross section of neutron capture reaction in keV energy region and fill the gap of domestic experimental data. Key laboratory of nuclear data at China Academy of Atomic Energy has built the first gamma-ray total absorption BaF2 facility in China based on back-streaming white neutron source at China spallation neutron source. The detection efficiency curve of gamma-ray is an important experimental parameter. Using the combination of experiment and simulation, the experimental results obtained by measuring 137Cs and 60Co sources are in good agreement with the simulation results of MCNP and GEANT4, which verifies the reliability of detection efficiency curve calculated by simulation. It will be used in the on-line measurement experiment of neutron capture reaction cross section.

Aiming at the problems of low efficiency and complicated data processing in the current manual reading method, an automatic test method for electromechanical conversion errors of smart water meters was proposed.Firstly, the structure of the intelligent water meter was analyzed, the principle of electromechanical conversion between the image recognition mechanical counter and the near-infrared communication reading electronic counter, the mechanical counting of the electromechanical conversion error device and the error test principle of the electronic counting were proposed. Then, the composition structure of the conversion device and the electromechanical error test flow were designed. Taking the 2-level lXS-DN15 wireless remote water meter as the object, the quality method water meter verification device was tested. Finally, in order to verify the validity of the above detection method, a specific test was set up and tested. The research results show that the efficiency of the test method can be increased by 38% compared with the original test method. It can realize the automatic measurement of the electromechanical conversion error of the water meter. This item can be tested together with indication error, and the test results meet the verification requirements. This test method effectively combines the static method with the dynamic method, and can realize rapid, efficient, and accurate automatic water meter verification. [ABSTRACT FROM AUTHOR]

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Semiconductor-based neutron-detectors are characterized by small size, high energy-resolution, good spatial resolution, and stable response (at the depletion voltage). Consequently, these neutron-detectors are important for the fields of nuclear proliferation prevention, oil exploration, monitoring neutron-scattering experiments, cancer treatments, and space radiation effect research. However, there are some well-known problems for conventional silicon-based neutron detectors: low neutron-detection efficiency and limited resistance to radiation. Therefore, critical improvements are needed to enable sufficiently effective and practical neutron detection. To address these problems, direct-conversion neutron detectors as well as wide bandgap semiconductor-based detectors have been developed and studied intensely during the past years. Significant progress with respect to detection efficiency, radiation resistance, and room temperature operation was achieved. This paper reviews the latest research highlights, remaining challenges, and emerging technologies of direct-conversion neutron detectors as well as wide-bandgap semiconductor neutron detectors. This compact review serves as a reference for researchers interested in the design and development of improved neutron detectors in the future. [ABSTRACT FROM AUTHOR]

Based on the lightning location data obtained by the World Wide Lightning Location Network (WWLLN), this study evaluates the real-time lightning detection performance of the Jianghuai Area Sferic Array (JASA) in inland and marine areas. A comparative analysis of the lightning activity during the visit of super typhoon Lekima (1909) showed that JASA and WWLLN had good consistency in radial distribution, temporal and spatial changes of typhoon-related lightning, and most of the lightning occurred where the cloud-top brightness temperature is less than 220 K. During the development stage of the typhoon, lightning activities in the inner core area were more frequent. When the typhoon matured and disappeared, lightning was mainly distributed in the outer rainband, and lightning activities in the inner core area were few but concentrated. In terms of detection efficiency, JASA's real-time location of lightning in the Jianghuai area was much more than WWLLN's, and its relative detection efficiency and absolute detection efficiency were 69.12% and 92.51%, respectively. In the marine area (114~130 °E, 20~ 24 °N and 123~130 °E, 24~32 °N), due to the limitation of JASA site layout, the real-time positioning number of lightning was slightly less than that of WWLLN, and its relative detection efficiency and absolute detection efficiency were 32.67% and 52.26%, respectively. The results show that JASA has a strong ability to capture inland and offshore thunderstorms, and provides data support for real-time monitoring of the evolution of strong convective lightning activities during typhoons'visits. Our analysis also provides a theoretical basis for further improving the site layout and support for improving the lightning detection performance in the open sea. [ABSTRACT FROM AUTHOR]

To assess the characteristics of 13N decay, a monitoring method of the primary loop leakage rate based on the y-y coincidence method was proposed. In this work, sampling and measure- ment devices were designed, in which NaI (TI) crystals were used as coincidence detectors. The Geant4 simulation method was used to study the relationship between the efficiency ε and capacity V change of different devices, and the εV value under the corresponding capacity was obtained. According to the value of εV, the optimal sampling and measurement device was determined, and then the detection efficiency of the device was calibrated experimentally. Taking the 600 000 kW reactor of Qinshan Phase II as the research object, the lower limit of detection was discussed. When the sampling point was located in the fume hood of the control rod drive mechanism, the theoretical lower limit of the coincidence method was 0.756 Lh-1. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Remote sensing techniques are becoming more sophisticated as radar imaging techniques mature. Synthetic aperture radar (SAR) can now provide high-resolution images for day-and-night earth observation. Detecting objects in SAR images is increasingly playing a significant role in a series of applications. In this paper, we address an edge detection problem that applies to scenarios with ship-like objects, where the detection accuracy and efficiency must be considered together. The key to ship detection lies in feature extraction. To efficiently extract features, many existing studies have proposed lightweight neural networks by pruning well-known models in the computer vision field. We found that although different baseline models have been tailored, a large amount of computation is still required. In order to achieve a lighter neural network-based ship detector, we propose Darts_Tiny, a novel differentiable neural architecture search model, to design dedicated convolutional neural networks automatically. Darts_Tiny is customized from Darts. It prunes superfluous operations to simplify the search model and adopts a computation-aware search process to enhance the detection efficiency. The computation-aware search process not only integrates a scheme cutting down the number of channels on purpose but also adopts a synthetic loss function combining the cross-entropy loss and the amount of computation. Comprehensive experiments are conducted to evaluate Darts_Tiny on two open datasets, HRSID and SSDD. Experimental results demonstrate that our neural networks win by at least an order of magnitude in terms of model complexity compared with SOTA lightweight models. A representative model obtained from Darts_Tiny (158 KB model volume, 28 K parameters and 0.58 G computations) yields a faster detection speed such that more than 750 frames per second ( 800 × 800 SAR images) could be achieved when testing on a platform equipped with an Nvidia Tesla V100 and an Intel Xeon Platinum 8260. The lightweight neural networks generated by Darts_Tiny are still competitive in detection accuracy: the F1 score can still reach more than 83 and 90, respectively, on HRSID and SSDD. [ABSTRACT FROM AUTHOR]

To assess the characteristics of 13N decay, a monitoring method of the primary loop leakage rate based on the γ-γ coincidence method was proposed. In this work, sampling and measurement devices were designed, in which NaI (Tl) crystals were used as coincidence detectors. The Geant4 simulation method was used to study the relationship between the efficiency e and capacity V change of different devices, and the eV value under the corresponding capacity was obtained. According to the value of eV, the optimal sampling and measurement device was determined, and then the detection efficiency of the device was calibrated experimentally. Taking the 600 000 kW reactor of Qinshan Phase II as the research object, the lower limit of detection was discussed. When the sampling point was located in the fume hood of the control rod drive mechanism, the theoretical lower limit of the coincidence method was 0.756 Lh-1.