S/C Band Harmonic Radar for Honey Bee Detection

This study proposed a method to evaluate proper experimental conditions of eddy current tests under a low signal-to-noise ratio. This method was applied to quantify the detection reliability of the eddy current test to detect corrosion pits on the surface of austenitic stainless-steel weld cladding from the perspectives of probability of detection and probability of false alarm. The fluctuations of flaw signal and noise were described using truncated bivariate normal distributions of a two-dimensional vector composed of the real and imaginary components of a signal. The probabilities of detection and false alarms were formalized as cumulative distributions of the estimated distributions of the maximum flaw signal and the noise exceeding a decision threshold. The receiver operating characteristic curves were created by coupling the probabilities of detection and false alarms at various thresholds. The area under the curve was used to quantify the detection reliability, simultaneously considering the probabilities of detection and false alarms. The results obtained in this study support the applicability of this method in quantitatively evaluating the detection reliability of a non-destructive inspection under a low signal-to-noise ratio.

This paper presents a novel analytical derivation of the false alarm probability (FAP) and detection probability (DP) for non-line-of-sight (NLOS) detection based on LTE signals. Position estimation in indoor or urban area with cellular wireless communication systems is getting more and more important. However, especially in these environments NLOS propagation causes positioning errors in the order of hundreds of meters. Thus, detection and mitigation of NLOS signals is a critical task. In this paper, we derive the FAP and DP on power-scaled detectors based on LTE multipath signals. The derivation considers frequency-selective fading channels taking sub-sample multipath interference, channel dynamics and initial frequency offsets into account. The results show a simple way to calculate the DP versus FAP. Simulation results verify the analytical probabilities for the WINNER II C2 channel model. Additionally, the simulations show the improved FAP of an antenna array at the receiver.

Hygienic behavior in honey bees is a critical for maintaining colony health, preventing the spread of diseases, and providing resistance to harmful parasites. This behavior is defined as the worker bees detecting diseased, dead or parasitized brood cells and removing and cleaning them from the honeycomb cells. This feature, which is the defense mechanism of the colony, has developed on a genetic basis in natural selection and controlled breeding processes. Therefore, understanding the genetic mechanisms of hygienic behavior has become an important research subject in honey bee breeding studies. Recent studies have shown that neurotransmitter systems and receptor genes in honeybees affect various social and cognitive processes, including hygienic behavior. It is known that biogenic amines, especially octopamine and tyramine, regulate the learning, memory, olfactory perception, decision-making mechanisms and social behaviors of bees. Octopamine receptor and tyramine receptor can have a direct effect on stress response, flight activity, foraging behavior and hygienic behavior by acting as stimulants in the nervous system. In this study, in order to understand the genetic basis of hygienic behavior in Efe ecotype honey bees (Apis mellifera anatoliaca), colonies showing hygienic and non-hygienic behavior were determined according to the pin-killed test. Then, single nucleotide polymorphisms (SNPs) were detected in the AmOA1 and AmTYR1 gene regions of worker bees belonging to these colonies. As a result of the sequence analysis, 10 polymorphisms were determined in the AmOA1 receptor gene and 11 polymorphisms were determined in the AmTYR1 receptor gene. However, no significant difference was observed in the distribution of these SNPs between colonies showing hygienic and non-hygienic behavior. These results indicate that there is no direct relationship between hygienic behavior in Efe Bees and SNPs in AmOA1 and AmTYR1 genes. Therefore, no differences were detected between colonies in terms of SNPs. The polymorphisms have not been reported before in Efe Bee and this contributes to the originality of the study. More comprehensive studies to be conducted in the future will increase the knowledge in this field and contribute to the development of new strategies for selecting colonies in terms of hygienic behavior in the beekeeping industry.

Mathematical modeling was carried out based on the experimentally measured fluorescence spectra of oil, vegetation and water to select the most effective spectral registration ranges for the fluorescent method for detecting oil leaks at an excitation wavelength of 355 nm. The results of mathematical modeling show that the probabilities of correct detection and false alarms for the problem of detecting oil leaks significantly depend on the type of oil and, accordingly, on the spectral channels selected for monitoring. For reliable detection of oil spills against the background of vegetation or water bodies, two or three spectral channels must be used. The highest probabilities of correct detection (>0.999) and small probabilities of false alarms (<0.04) can be achieved for oils with intensity maxima of laser-induced fluorescent radiation at wavelengths of ~ 420 and 550 nm (when using two spectral channels) and for oils with fluorescence intensity maximum at a wavelength of ~510 nm (when using three spectral channels). For oils with a maximum fluorescence intensity at a wavelength of about 475 nm (when using three spectral channels), the results are worse, although they remain acceptable (at a measurement noise of 10%, the probability of correct detection and false alarms, respectively, 0.94 and 0.11).

SUMMARYIn this paper, a novel sensing scheme, uniform quantization for cooperative sensing (UniQCS), that employs a uniform quantizer is proposed. UniQCS is based on energy detection and uses weight vector for global decision function. It performs better than hard decision algorithms such as majority and k‐out‐of‐n in terms of probability of detection and false alarm at the cost of a marginal increase in overhead bits under imperfect reporting channel and false reports. The probability of detection is maximized for a given probability of false alarm constraint by the proposed method. For detailed analysis, the UniQCS is compared with equal gain combiner scheme, which performs far better than hard decision algorithms, via highest bandwidth requirement. The proposed algorithm performs close to equal gain combiner. Moreover, the robustness of UniQCS to sensing error is analyzed when some nodes always report false decisions to the fusion center and the reporting channel is imperfect. For probability of false alarm equal to 0.01, performance gain of UniQCS is at least 45% compared with the other methods when there are two false reporting nodes. UniQCS performance gain is at least 15% compared with other methods for probability of reporting channel error equal to 0.001. Copyright © 2012 John Wiley & Sons, Ltd.

In cognitive radio networks, the secondary users can use the frequency bands when the primary users are not present. Hence secondary users need to constantly sense the presence of the primary users. When the primary users are detected, the secondary users have to vacate that channel. This makes the probability of detection important to the primary users as it indicates their protection level from secondary users. When the secondary users detect the presence of a primary user which is in fact not there, it is referred to as false alarm. The probability of false alarm is important to the secondary users as it determines their usage of an unoccupied channel. Depending on whose interest is of priority, either a targeted probability of detection or false alarm shall be set. After setting one of the probabilities, the other can be optimized through cooperative sensing. In this paper, we show that cooperating all secondary users in the network does not necessary achieve the optimum performance, but instead, it is achieved by cooperating a certain number of users with the highest primary user's signal to noise ratio. Computer simulations have shown that the P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> can increase from 92.03% to 99.88% and P <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</sub> can decrease from 6.02% to 0.06% in a network with 200 users.

The mango is one of the essential fruit trees for the economy of Thailand. Mango pollination relies primarily on insects. Other external forces, such as wind, are less efficient since pollen is sticky and aggregating. There is only one report from Thailand on the use of bees as mango pollinators. The study of the behavior and pollination efficiency of honey bees (Apis mellifera) and stingless bees (Tetragonula laeviceps species complex) was conducted in Nam Dokmai mango plantings in Phrao and Mae Taeng districts, Chiang Mai province, between February and March 2019. Results: Our results reveal that the honey bees commenced foraging earlier than the stingless bee. The number of flowers visited within 1 minute by honey bees was higher than that visited by stingless bees. The average numbers of honey bees and stingless bees that flew out of the hive per minute from 7 a.m. and 6 p.m. in the Phrao district were 4.21 1.62 and 9.88 7.63 bees/min, respectively, i.e., higher than those observed in Mae Taeng, which were 3.46 1.13 and 1.23 1.20 bees/min, respectively. The numbers of fruits per tree were significantly higher in the honey bee and stingless bee treatments (T1 and T2) than in the open pollination treatment (T3). The number of fruits between T1 and T2 treatments was not different. In the pollinator exclusion treatment (T4), no fruit was produced. Fruit size factors were not significantly different among T1, T2, and T3 treatments. Conclusions: Our results showed that insect pollination is crucial for mango production, especially with the Nam Dokmai variety in Northern Thailand. As pollinator exclusion treatment showed no fruit set, and pollinator treatment significantly increased the fruit sets compared to open access plots, a managed pollinator program would benefit the mango growers for better productivity. Both the honey bee and the stingless bee were shown to be effective as pollinators.

In contrast to conventional radar, harmonic radar systems utilize two different frequencies for transmission and reception. Therefore, a desired target is equipped with a tag that includes a frequency doubler. It exclusively reflects the signal at twice the originally sent out frequency, making this specific target unique. Thus, enabling the key advantage of harmonic radar systems: clutter rejection. However, the range equation of such a system deviates significantly from conventional radar. This is mostly due to the power transfer function of the required doubler. Therefore, achieving sufficient range to satisfy a desired application is challenging. In this article, the measures with which state-of-the-art systems address those challenges are reviewed and explained with the help of this deviating range equation. Furthermore, this article highlights the potential of utilizing active tags as well as other research to increase realizable ranges and the frequencies of harmonic radar into the mmWaves, respectively.

In pest management research, harmonic radar systems have been largely used to study insect movement across open or vegetation-poor areas because the microwave signal is attenuated by the high water content of vegetation. This study evaluated whether the efficacy of this technology is sufficient to track insects in vegetative landscapes. Field efficacy data were collected using portable harmonic microwave radar and electronic dipole tags mounted on adults of three economically important pests: Leptinotarsa decemlineata (Say), Diabrotica virgifera virgifera (LeConte) [corrected] and Conotrachelus nenuphar Herbst. Detection and recovery of tagged Colorado potato beetles, plum curculios and western corn rootworms was high within and among potato plants, moderate within apple trees and high within, but not between, corn plants respectively. The efficacy of the radar depends on the ability of the operator to move around the host, scanning for a signal 'sightline' with the tagged insect among plant structures. The detection rate of tagged insects by harmonic radar systems is high enough to track the walking path of pests through low row crops such as potato, tall row crops such as corn or tall but well-separated trees of orchard-type crops by adapting the scanning procedure to the vegetative architecture.

In this paper, we optimize probability of detection and probability of false alarm in cognitive radio network to minimize probability of error of a particular SU in a centralized cognitive radio network using Genetic algorithm (GA). Our objective is to minimize probability of error and find out optimum values of probability of occupancy detection or probability of detection and probability of false alarm. We use Genetic Algorithm to solve this optimization problem. The result is compared with Differential Evolution algorithm and it is evident from the comparison that DE finds better solution and takes much lesser number of evaluations to find optimum solution.

Harmonic radar is a promising radar technique for the detection of electronic devices in security related applications. In contrast to established and commercially available systems, where the radar works in conjunction with a known and cooperative transponder responding at a harmonic frequency, the goal here is to detect and localize noncooperative targets such as mobile phones. In this work, a combination of classic and harmonic radar in one system is presented. The system layout together with the design strategies and experiences gained is described in detail. Measurement results indicate how an inverse synthetic aperture radar (ISAR) setup could be beneficial in a real world scenario.

The development of wireless technology and the desire to improve communication electromagnetic fields (EMFs) of various frequencies have become common across the honey bee’s foraging landscape. There has been discussion for many years about the possible impact of electromagnetic fields on living organisms. Artificial radio fields emit frequencies ranging from 100 kHz to 300 GHz. The presented research aimed to demonstrate the influence of the radiofrequency electromagnetic field (RF-EMF) with a frequency of 900 MHz on the behavior of honey bees in laboratory conditions. For this experiment, we used wooden cages to house honey bee workers immediately after they emerged. Bee workers were divided into control and experimental groups. Bees in the control group were not exposed to RF fields, while the experimental groups were exposed to 900 MHz electromagnetic fields of different intensities and durations of exposure. Bees’ behavior was analyzed with an appropriate computer program. Behavioral analysis of bees was performed immediately after exposure and seven days after exposure. Our research has shown that the radio field (900 MHz) affects the behavior of bees compared to the control group, although not all results are statistically significant. Significant effects were observed seven days after exposure in walking, flight, and individual contact. However, it is worth extending the study to include the impact of an RF-EMF on the expression of genes responsible for bee behavior.

Hygienic behavior is a key trait in the western honey bee (Apis mellifera) associated with resistance to diseases and tolerance to the parasitic mite Varroa destructor. Worker bees expressing this behavior are able to detect and remove unhealthy or infested brood, thereby limiting pathogen transmission and mite reproduction. In recent years, the gut microbiota has emerged as an important factor in honey bee health, influencing immunity and disease resistance. Hygienic behavior is a form of social immune defense; however, whether gut microbiota composition contributes to variation in this disease-resistance mechanism remains poorly understood. This study investigated the relationship between gut microbiota composition and hygienic behavior in a honey bee breeding population selected for docility, honey production, and hygiene since 2015.Seventy-seven colonies were sampled at three time points between June and October 2021 for gut microbiota analysis using high-throughput sequencing. Hygienic behavior was evaluated using the average pin test score, calculated from tests performed in March and July. Significant association were identified between gut microbiota diversity and hygienic behavior, with marked seasonal pattern. Colonies with higher pin test scores showed increased alpha diversity in October, while beta-diversity analyses indicated significant difference in July. In particular, LAB genera such as Lactobacillus, Bifidobacterium, and Bombilactobacillus, were more abundant in highly hygienic colonies in July, suggesting a microbiota configurations potentially linked enhanced immune capacity and resilience to brood diseases and Varroa infestations.Overall, these findings support a seasonal association between gut microbiota composition and hygienic behavior in honey bees and highlight specific microbial taxa that may contribute to colony robustness. This study provides a basis for future research exploring the functional role of microbiota in social immunity and its potential integration into selective breeding strategies aimed at improving colony health.

Two behaviours of honey bees, hygienic and grooming, are mechanisms of defense against brood diseases and parasitic mites, including Varroa destructor. Apis mellifera colonies remove the worker brood infested with Varroa destructor mites from the nest (hygienic behaviour), and groom the mites off other adult bees (grooming behaviour). In this study hygienic and grooming behaviours of Sjeničko-Pešterski honey bee ecotype were analysed in 440 honey bee colonies from 11 localities in the region of Sjeničko-Pešterski plateau, Podpešterje, Golija Mt. and Rogozna ML At each locality 40 honey bee colonies were investigated: 10 potent colonies with one-year old queen, 10 potent colonies with two-year old queen, 10 medium potent and 10 weak honey bee colonies. Hygienic behaviour was expressed in a range from 95.12% to 99.50% in potent honey bee colonies with one-year old and two-year old queens. Statistically highly significant (p<0.01) differences were registered among the analysed honey bee colonies at the investigated region, in favour of the potent honey bee colonies, compared to the medium potent and weak colonies. Also, statistically highly significant (p<0.01) differences were recorded between potent colonies with one-year old queens and colonies with two-year old queens, in favour of the colonies with one-year old queens. In general, investigated colonies belong to a category of the so called "hygienic colonies", as the efficiency of elimination of damaged pupae amounted to 91.50%. Grooming behaviour of Sjeničko-Pešterski honey bee ecotype potentially exists, but its significance cannot be discussed as, on the whole, investigated colonies showed potential of 34,04%. Our results point to an indisputable relationship between analysed behaviours and the strength of honey bee colonies: hygienic behaviour is more expressed in potent colonies (from 95.12% to 99.50%) regardless of queen age; grooming behaviour was expressed only in potent honey bee colonies with one-year old queen at all 11 localities, where the number of damaged mites ranged from 36,05% to 39,61%. The damaged mites were separated into six categories. The most frequent category of damage was damaged legs (53.38% in potent colonies with one-year old queens and 52.02% in potent colonies with two-year old queens). The potent honey bee colonies from the investigated region especially with one-year old queen, could be used for highly selected breeds improving and queens rearing.

Brain transcriptional regulatory network for behavior demonstrates that brain gene expression in the honey bee can be accurately predicted from the expression transcription factors (TFs), but roles for specific TFs are less understood. Mushroom bodies (MBs) are important for learning, memory and sensory integration in the honey bee brain. A TFs, Mblk-1, expressed preferentially in the large-type Kenyon cells of the honeybee MBs is predicted to be involved in brain function by regulating transcription of its target genes in honey bee. However, its function and the mechanism of regulation in behavior of honey bee is still obscure. Here we show that Mblk-1 had significantly higher expression in the brains of forager bees relative to nurse bees. Mblk-1 was significantly inhibited in bees fed small interfering RNA. In addition, inhibition of Mblk-1 decreased sucrose responsiveness in foragers. Finally, we determined that Mblk-1 regulated the messenger RNA of AmGR1. These findings suggest that Mblk-1 may target AmGR1 to regulate the sucrose responsiveness of foragers.