ANALYSIS OF MULTI-CHANNEL TWO-DIMENSIONAL PROBABILITY CSMA AD HOC NETWORK PROTOCOL BASED THREE-WAY HANDSHAKE MECHANISM

In wireless Ad Hoc networks, large number and flexible mobility of terminals lead to the rarity of wireless channel resources. Also the hidden and exposed terminal problem exists in the Ad Hoc network which is the major factors restricting its development and applying. Considering these factors, this paper proposes a new CSMA protocol: multi-channel two-dimensional probability CSMA for wireless Ad Hoc network protocol based on three-way handshake mechanism, and analyzes the system throughput, delay of information packet, energy consumption and other properties under the control of the proposed protocol. By using the cycle analysis method, computer simulation results not only verify the theoretical analysis, but also show that the protocol has the optimum performance. The proposed protocol can not only reduce the collision probability of information packets to some extent, improving the channel utilization, reducing the waste of channel resources, but also achieve the balancing of load in a variety of wireless Ad Hoc network services, meeting the needs by different priorities with different QoS, and ensuring the systematic efficiency and fairness

The Probability Detection CSMA Protocol with Monitoring Function in WSNs and Energy Efficiency Analysis

The paper presents a new WLAN (wireless local area network) MAC protocol, probability detection CSMA with monitoring for WSNs MAC protocol. Analyzes and builds the corresponding mathematical model using average cycle method, and get the mathematical expressions of systemic throughput and the life cycle of terminal nodes of the probability detection CSMA with monitoring for WSNs MAC protocol through a rigorous mathematical derivation. Simulation results show that the probability detection CSMA with monitoring for WSNs MAC protocol due to join the monitoring signal, resulting in the decrease of systemic throughput, but reduces the collision probability. Meanwhile, under the control of the protocol, the systemic throughput and utilization rate has a higher value in the light loads, then avoid the waste of channel resources. Therefore, the probability detection CSMA with monitoring for WSNs MAC protocol has a better performance in the WLAN

The P-persistent CSMA Protocol with Monitoring Function in WSN and the Analysis of the Protocol

This paper presents a new p-persistent CSMA wireless sensor network MAC protocol with monitoring function based on random multiple access system, and gets the mathematical expressions of system throughput, system average operating power and the life cycle of terminal nodes of p-persistent CSMA wireless sensor network MAC protocol with monitoring function through complicated mathematical modeling, rigorous mathematical derivation and using average period analysis. The computer simulation results not only confirm the correctness of the theoretical analysis but also show that the p-persistent CSMA with monitoring for WSNs MAC protocol due to join the monitoring signals, resulting in the decrease of systemic throughput, but reduce the collision probability. Meanwhile, the p-persistent CSMA wireless sensor network MAC protocol with monitoring function this paper presents can effectively reduce energy consumption

Responses of Phaseolus calcaltus to lime and biochar application in an acid soil

Introduction Rice bean (Phaseolus calcaltus), as an annual summer legume, is always subjected to acid soils in tropical to subtropical regions, limiting its growth and nodulation. However, little is known about its responses to lime and biochar addition, the two in improving soil fertility in acid soils. Materials and Methods In the current study, a pot experiment was conducted using rice bean on a sandy yellow soil (Orthic Acrisol) with a pH of 5.5. The experiment included three lime rates (0, 0.75 and 1.5 g kg−1) and three biochar rates (0, 5 and 10 g kg−1). The biochar was produced from aboveground parts of Solanum tuberosum using a home-made device with temperature of pyrolysis about 500 °C. Results and Discussion The results indicated that both lime and biochar could reduce soil exchange Al concentration, increase soil pH and the contents of soil microbial biomass carbon and microbial biomass nitrogen, and enhance urease and dehydrogenase activities, benefiting P. calcaltus growth and nodulation in acid soils. Lime application did decrease the concentrations of soil available phosphorus (AP) and alkali dispelled nitrogen (AN), whereas biochar application increased the concentrations of soil AP, AN and available potassium (AK). However, sole biochar application could not achieve as much yield increase as lime application did. High lime rate (1.5 g lime kg−1) incorporated with low biochar rate (5 g biochar kg−1) could obtain higher shoot biomass, nutrient uptake, and nodule number when compared with high lime rate and high biochar rate. Conclusion Lime incorporated with biochar application could achieve optimum improvement for P. calcaltus growing in acid soils when compared with sole lime or biochar addition

Gut-joint axis in knee synovitis: gut fungal dysbiosis and altered fungi–bacteria correlation network identified in a community-based study

Objectives: Knee synovitis is a highly prevalent and potentially curable condition for knee pain; however, its pathogenesis remains unclear. We sought to assess the associations of the gut fungal microbiota and the fungi–bacteria correlation network with knee synovitis. Methods: Participants were derived from a community-based cross-sectional study. We performed an ultrasound examination of both knees. A knee was defined as having synovitis if its synovium was ≥4 mm and/or Power Doppler (PD) signal was within the knee synovium area (PD synovitis). We collected faecal specimens from each participant and assessed gut fungal and bacterial microbiota using internal transcribed spacer 2 and shotgun metagenomic sequencing. We examined the relation of α-diversity, β-diversity, the relative abundance of taxa and the interkingdom correlations to knee synovitis. Results: Among 977 participants (mean age: 63.2 years; women: 58.8%), 191 (19.5%) had knee synovitis. β-diversity of the gut fungal microbiota, but not α-diversity, was significantly associated with prevalent knee synovitis. The fungal genus Schizophyllum was inversely correlated with the prevalence and activity (ie, control, synovitis without PD signal and PD synovitis) of knee synovitis. Compared with those without synovitis, the fungi–bacteria correlation network in patients with knee synovitis was smaller (nodes: 93 vs 153; edges: 107 vs 244), and the average number of neighbours was fewer (2.3 vs 3.2). Conclusion: Alterations of gut fungal microbiota and the fungi–bacteria correlation network are associated with knee synovitis. These novel findings may help understand the mechanisms of the gut-joint axis in knee synovitis and suggest potential targets for future treatment

How Abusive Supervision Affects Employees’ Unethical Behaviors: A Moderated Mediation Examination of Turnover Intentions and Caring Climate

Drawing on psychological contract theory, this research contributes to the unethical behavior literature by exploring employees’ turnover intentions as a mediator of the relationship between abusive supervision and employees’ unethical behavior and the moderating role of the caring climate in the relationship between turnover intentions and unethical behavior. The results from a sample of 679 reveal that turnover intentions mediate relationship between abusive supervision and subordinates’ unethical behavior, and caring climate moderates the positive relationship between turnover intentions and subordinates’ unethical behavior. We also find that the indirect effect is moderated by the caring climate. The theoretical and practical implications are discussed