average transmission rate

Background: It is important to improve the quality of service by using congestion detection technology to find the potential congestion as early as possible in wireless sensor network. Methods: So an improved congestion control scheme based on traffic assignment and reassignment algorithm is proposed for congestion avoidance, detection and mitigation. The congestion area of the network is detected by predicting and setting threshold. When the congestion occurs, sensor nodes can be recovery quickly from congestion by adopting reasonable method of traffic reassignment. And the method can ensure the data in the congestion areas can be transferred to noncongestion areas as soon as possible. Results: The simulation results indicate that the proposed scheme can reduce the number of loss packets, improve the throughput, stabilize the average transmission rate of source node and reduce the end-to-end delay. Conclusion: : So the proposed scheme can enhance the overall performance of the network. Keywords: wireless sensor network; congestion control; congestion detection; congestion mitigation; traffic assignment; traffic reassignment.

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Changing sex for selfish gain: B chromosomes of Lake Malawi cichlid fish

Scientific Reports ◽

10.1038/s41598-019-55774-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 6

Author(s):

Frances E. Clark ◽

Thomas D. Kocher

Keyword(s):

Linkage Group ◽

Transmission Rate ◽

Cichlid Fish ◽

Meiotic Drive ◽

B Chromosome ◽

Lake Malawi ◽

B Chromosomes ◽

Normal Complement ◽

Biased Sex Ratio ◽

Average Transmission

AbstractB chromosomes are extra, non-essential chromosomes present in addition to the normal complement of A chromosomes. Many species of cichlid fish in Lake Malawi carry a haploid, female-restricted B chromosome. Here we show that this B chromosome exhibits drive, with an average transmission rate of 70%. The offspring of B-transmitting females exhibit a strongly female-biased sex ratio. Genotyping of these offspring reveals the B chromosome carries a female sex determiner that is epistatically dominant to an XY system on linkage group 7. We suggest that this sex determiner evolved to enhance the meiotic drive of the B chromosome. This is some of the first evidence that female meiotic drive can lead to the invasion of new sex chromosomes solely to benefit the driver, and not to compensate for skewed sex ratios.

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On the Design of Rate Adaptation for Relay-Assisted Satellite Hybrid FSO/RF Systems

10.36227/techrxiv.15177573.v1 ◽

2021 ◽

Author(s):

Hoang Le ◽

Thang Nguyen

Keyword(s):

Satellite Communication ◽

Performance Metrics ◽

Transmission Rate ◽

Rate Adaptation ◽

Spectrum Efficiency ◽

Free Space Optical ◽

Fixed Rate ◽

Rf Systems ◽

Average Transmission ◽

The Impact

<p>This paper addresses the design of hybrid free-space optical/radio frequency (FSO/RF) systems for a high-altitude platform (HAP)-aided relaying satellite communication for mobile networks supported by unmanned aerial vehicle (UAV). While prior work primarily focused on fixed-rate design, which frequently switches between FSO and RF lead to reduce the system performance, we propose a rate adaptation design that gradually adjusts the data rate in each link when its channel state fluctuates. The proposed design's downlink performance is analyzed, taking into account many challenging issues, including beam spreading loss, cloud attenuation, statistical behaviors of the atmospheric turbulence in the dual-hop channel, and pointing misalignment due to the UAV hovering. Different performance metrics are analytically derived based on channel modelings, such as outage probability, average transmission rate, achievable spectrum efficiency, and average transmission rate. The numerical results quantitatively confirm the effectiveness of our proposed system under the impact of UAV hovering misalignment and atmospheric-related issues like clouds and turbulence. Finally, Monte-Carlo simulations validate the accuracy of theoretical results.</p>

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Average Transmission Rate and Outage Performance of Relay-Assisted Satellite Hybrid FSO/RF Systems

10.36227/techrxiv.14971587 ◽

2021 ◽

Author(s):

Thang Nguyen

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Free Space ◽

System Performance ◽

Performance Metrics ◽

Transmission Rate ◽

Free Space Optical ◽

Fixed Rate ◽

Rf Systems ◽

Average Transmission

<div> <div> <div> <p>This paper proposes a rate adaptation design for high altitude platform (HAP)-aided relaying satellite hybrid free-space optical/radio-frequency (FSO/RF) systems. The design allows switching between two links gradually to reduce the fre- quent link switching in error-prone environments of conventional fixed-rate hybrid FSO/RF systems. System performance metrics, including average transmission rate and outage probability, are analytically studied under the presence of clouds and fading of FSO and RF channels modeled respectively by Gamma-Gamma and Rician distributions. The numerical results quantitatively highlight the effectiveness of our proposed systems over the conventional ones. Moreover, Monte-Carlo simulations are also performed to validate the accuracy of the analytical model. </p> </div> </div> </div>

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Symbiont Survival and Host-Symbiont Disequilibria Under Differential Vertical Transmission

Genetics ◽

10.1093/genetics/154.3.1347 ◽

2000 ◽

Vol 154 (3) ◽

pp. 1347-1365

Author(s):

María S Sánchez ◽

Jonathan Arnold ◽

Marjorie A Asmussen

Keyword(s):

Vertical Transmission ◽

De Novo ◽

Initial Conditions ◽

Transmission Rate ◽

Evolutionary Forces ◽

Transmission Parameters ◽

Baseline Case ◽

Average Transmission ◽

Host Genetic ◽

Differential Transmission

Abstract Interspecific genetic interactions in host-symbiont systems raise intriguing coevolutionary questions and may influence the effectiveness of public health and management policies. Here we present an analytical and numerical investigation of the effects of host genetic heterogeneity in the rate of vertical transmission of a symbiont. We consider the baseline case with a monomorphic symbiont and a single diallelic locus in its diploid host, where vertical transmission is the sole force. Our analysis introduces interspecific disequilibria to quantify nonrandom associations between host genotypes and alleles and symbiont presence/absence. The transient and equilibrium behavior is examined in simulations with randomly generated initial conditions and transmission parameters. Compared to the case where vertical transmission rates are uniform across host genotypes, differential transmission (i) increases average symbiont survival from 50% to almost 60%, (ii) dramatically reduces the minimum average transmission rate for symbiont survival from 0.5 to 0.008, and (iii) readily creates permanent host-symbiont disequilibria de novo, whereas uniform transmission can neither create nor maintain such associations. On average, heterozygotes are slightly more likely to carry and maintain the symbiont in the population and are more randomly associated with the symbiont. Results show that simple evolutionary forces can create substantial nonrandom associations between two species.

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average transmission rate

10.1007/springerreference_8613 ◽

2011 ◽

Keyword(s):

Transmission Rate ◽

Average Transmission

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On the Design of Rate Adaptation for Relay-Assisted Satellite Hybrid FSO/RF Systems

10.36227/techrxiv.15177573.v2 ◽

2021 ◽

Author(s):

Hoang Le ◽

Thang Nguyen

Keyword(s):

Satellite Communication ◽

Performance Metrics ◽

Transmission Rate ◽

Rate Adaptation ◽

Spectrum Efficiency ◽

Free Space Optical ◽

Fixed Rate ◽

Rf Systems ◽

Average Transmission ◽

The Impact

<p>This paper addresses the design of hybrid free-space optical/radio frequency (FSO/RF) systems for a high-altitude platform (HAP)-aided relaying satellite communication for mobile networks supported by unmanned aerial vehicle (UAV). While prior work primarily focused on fixed-rate design, which frequently switches between FSO and RF lead to reduce the system performance, we propose a rate adaptation design that gradually adjusts the data rate in each link when its channel state fluctuates. The proposed design's downlink performance is analyzed, taking into account many challenging issues, including beam spreading loss, cloud attenuation, statistical behaviors of the atmospheric turbulence in the dual-hop channel, and pointing misalignment due to the UAV hovering. Different performance metrics are analytically derived based on channel modelings, such as outage probability, average transmission rate, achievable spectrum efficiency, and average transmission rate. The numerical results quantitatively confirm the effectiveness of our proposed system under the impact of UAV hovering misalignment and atmospheric-related issues like clouds and turbulence. Finally, Monte-Carlo simulations validate the accuracy of theoretical results.</p>

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Average Transmission Rate and Outage Performance of Relay-Assisted Satellite Hybrid FSO/RF Systems

10.36227/techrxiv.14971587.v1 ◽

2021 ◽

Author(s):

Thang Nguyen

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Free Space ◽

System Performance ◽

Performance Metrics ◽

Transmission Rate ◽

Free Space Optical ◽

Fixed Rate ◽

Rf Systems ◽

Average Transmission

<div> <div> <div> <p>This paper proposes a rate adaptation design for high altitude platform (HAP)-aided relaying satellite hybrid free-space optical/radio-frequency (FSO/RF) systems. The design allows switching between two links gradually to reduce the fre- quent link switching in error-prone environments of conventional fixed-rate hybrid FSO/RF systems. System performance metrics, including average transmission rate and outage probability, are analytically studied under the presence of clouds and fading of FSO and RF channels modeled respectively by Gamma-Gamma and Rician distributions. The numerical results quantitatively highlight the effectiveness of our proposed systems over the conventional ones. Moreover, Monte-Carlo simulations are also performed to validate the accuracy of the analytical model. </p> </div> </div> </div>

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Infection and transmission of the facultative endosymbiont Arsenophonus in the spider Pardosa pseudoannulata

10.21203/rs.3.rs-48416/v1 ◽

2020 ◽

Author(s):

Hanqi Jiang ◽

Yu Ding ◽

Dongxiao Zhao ◽

Xiangdong Liu ◽

Huifang Guo

Keyword(s):

Genetic Differentiation ◽

Insect Pests ◽

Transmission Rate ◽

The Other ◽

Diagnostic Pcr ◽

Pardosa Pseudoannulata ◽

Rice Planthoppers ◽

Geographical Regions ◽

Important Predator ◽

Average Transmission

Abstract Background The infection of insect pests and their parasitoids with the facultative endosymbiont Arsenophonus has been well studied, whereas the infection of the predators of insect pests with this symbiont is less well understood. We studied this symbiont in the spider Pardosa pseudoannulata, an important predator of rice planthoppers, collected from rice paddies in 8 geographical regions in China.Results Diagnostic PCR showed that Arsenophonus was present in 4 of the 8 sampled populations of spiders. In these 4 populations, the infection incidence was between 2.1% and 16.7% and significantly differed between the Lishui population and the other three populations. Investigation of symbiont infection in both females and their offspring indicated that Arsenophonus can be vertically transmitted in P. pseudoannulata; the average transmission rate was approximately 25%. Remarkably, Arsenophonus was present in approximately 11% of the offspring of uninfected females, indicating that nonmaternal transmission occurs in this spider.Conclusions Populations of the spider P. pseudoannulata are infected at low rates with the symbiont Arsenophonus. This symbiont can be vertically transmitted from female spiders to offspring but may also be transmitted by male spiders or other vectors. Arsenophonus populations from different geographical regions exhibit genetic differentiation.

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Cytogenetics of an unstable trisomie in barley (Hordeum vulgare)

Genome ◽

10.1139/g93-048 ◽

1993 ◽

Vol 36 (2) ◽

pp. 350-355

Author(s):

R. J. Singh ◽

T. Tsuchiya

Keyword(s):

Transmission Rate ◽

Meiotic Chromosome ◽

Extra Chromosome ◽

Low Frequency ◽

Chromosome Elimination ◽

Metacentric Chromosome ◽

Chromosome 3 ◽

Chromosome Behavior ◽

Chromosome Configuration ◽

Average Transmission

The origin, identification, meiotic chromosome behavior, and breeding behavior of an unstable trisomic barley were studied. The extra chromosome originated by breakage and fusion of an acrocentric chromosome 3 in a plant from an F2 population of a cross between acrotrisomic 3L3S (2n = 14 + 1 acro3L3S) and a balanced lethal stock, xc. (xantha) ac (albino). The F2 population segregated only for the albino trait. The genotypic constitution of the trisomic plant was ac ac (for both normal chromosome 3) and Ac (for the unstable metacentric chromosome). The unstable extra metacentric chromosome was designated as metacentric 3B (abbreviated as meta3B). Meiotic chromosome behavior in plants with 2n = 14 + 1 meta3B differed from plant to plant and within spikes. Some plants showed only trisomic cells with a chromosome configuration of 1 III + 6 II and 7 II + 1 I at metaphase I, whereas other plants showed both trisomie and disomic cells (7 II) that resulted from the elimination of the extra meta3B. The frequency of ring trivalents was low (6.8%). An average transmission rate of unstable meta3B ranged from 4.3 to 12.9%. The elimination of meta3B, and hence loss of the dominant Ac allele, resulted in albino seedlings as well as white stripes on plants, leaves, and spikes. Chromosome numbers of albino seedlings in the progeny of 2n = 14 + 1 meta3B were all diploid (2n = 14), while green seedlings contained 2n = 14 + 1 meta3B. However, progenies of some spikes of one trisomic plant showed a low frequency of green diploids and metatrisomics (2n = 14 + 1 meta3B), which was attributed to crossing-over.Key words: aneuploid, chromosome elimination, kinetochore, meta3B.

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