Probability Of Entrance Research Articles

Optimal strategy analysis of a Markovian queue with variable vacation and vacation interruptions under unobservable cases

ABSTRACT This paper makes a game-theoretic analysis of an M/M/1 queue with variable vacation and vacation interruptions. The Nash equilibrium mixed strategy and social utility maximization are derived based on a non-cooperative game theory and an optimization theory under different information precision levels, namely almost unobservable and fully unobservable cases. The explicit solutions of the entrance probabilities and the steady-state probability distribution of the system are investigated using the probability generating function and nonhomogeneous linear difference equations. Furthermore, the effects of the information levels and diverse system parameters on the equilibrium strategies, the arrival rates, and the expected benefits are explicitly illustrated by numerical comparisons. The research results can provide a theoretical basis and performance analysis tool for the optimal design in the wireless transmission and network communication system.

Improving size selection in the Norwegian red king crab (Paralithodes camtschaticus) fishery through modification to pot design and soak time.

Red king crab (Paralithodes camtschaticus) represent a valuable inshore fisheries resource for communities in northern Norway. The fishery is regulated east of the 26th meridian by vessel quotas and a minimum landing size of 130 mm carapace length. It is executed using baited pots that must be fitted with circular escape openings. Despite this, pot catches typically contain a large proportion of sub-legal sized crab. This implies increased labor-intensive sorting which can lead to crab becoming injured, loosing limbs or delayed mortality. Such consequences negatively impact the sustainability of the fishery. In this study, we examined the potential of two new pot designs and longer soak times to reduce undersized crab catches in comparative field trials. A design consisting of a tarpaulin panel on the pot entrance (intended to prevent undersized individuals from gaining traction and entering) was found to be no better at reducing undersized catches than the currently used commercial design fitted with escape openings. A second design with a baited lower chamber (which could be accessed through the pot floor via escape openings) was intended to motivate undersized crab to escape more readily. If fished commercially, any crab in the bottomless lower chamber would be left behind on the seabed upon hauling. This design was found to have minimal effects on sublegal catches. However, increasing the soak time of the currently used commercial design from 1 day to 4 days reduced undersized crab catches substantially. This effect is likely related to bait becoming exhausted over time, thereby increasing the opportunity and motivation of sublegal crab to find and exit the pot through the mandatory escape openings. Laboratory-based behavioural observations using the panel design indicated that entry was dependent on crab orientation and that crab were less successful at entering than for the commercial design. However, all sizes of crab used an unintentional fold in the panel to increase their entrance probability. This may explain the lack of success of this design during the field trials. We conclude that ensuring bait is exhausted by employing longer soak times than is typically used by fishers would reduce catches of undersized crab in the fishery. Data availability statementThe data underlying this article will be shared on reasonable request to the corresponding author.

Ecological connectivity of the upper Rhône River: Upstream fish passage at two successive large hydroelectric dams for partially migratory species

The restoration of migration pathways for fish is crucial for the maintenance of populations in a worldwide context of increasing river fragmentation due to the development of dams. Studies aiming at quantifying fish passage at dams through fishway efficiency estimates concern few species, mostly diadromous. Data are lacking regarding most potamodromous species, despite their need to move to complete their life cycles. This study aimed to evaluate the efficiency of two vertical slot fishways for upstream fish migration on two consecutive run-of-the-river hydropower dams (Verbois and Chancy-Pougny) on the Rhône River. Radiotelemetry and PIT-tagging were used together (1) to describe the behaviour of fish under the dams and (2) to quantify entrance probability and passage efficiency of the fishways, for three potamodromous, partially migratory species, comprising of two cyprinids (Barbus barbus and Squalius cephalus) and one salmonid (Salmo trutta). The study revealed that fish preferentially moved upstream of the dam beside the gates, independently of their opening, rather than in the main flow of the turbines. While the passability of fishways did not differ among species (68% for all species), the attractiveness was dependent on the dam/fishway, the species and some individual characteristics such as fish body length and condition. A few fish remained below the gates or near the fishway for a long time, up to several months, without being able to detect the entrance. Overall, results revealed a lower efficiency of the fishways for trout than for the two cyprinids. Attraction was pointed out as the major limiting factor to the efficiency of the Verbois fishway for barbel and trout. Overall, results suggested to better account for fish motivation (migratory behaviour) to assess fishway efficiency for these species.

Service pricing and customer behaviour strategies of Stackelberg's equilibrium in an unobservable Markovian queue with unreliable server and delayed repairs

In this paper, we model as a Stackelberg game with the service pricing of server and the strategic behaviour of customers in a totally unobservable M/M/1 queueing system subject to random breakdowns and delayed repairs, under a reward-cost structure. For this, we first use the partial generating functions to determine the steady-state condition and the sojourn time of a customer in the considered queueing system. The analytical forms of the service price and the customer entrance strategies of the Stackelberg equilibrium of the game are given. Through numerical examples, we illustrate the effect of the price and the reliability parameters on the entrance probability of customers and the server profit. Finally, we define and solve the corresponding social welfare problem. This study has not only a theoretical aspect, but also a practical one, and it can be adapted to several real-life situations.

The risk assessment on the security of industrial internet infrastructure under intelligent convergence with the case of G.E.'s intellectual transformation.

The industrial internet depends on the development of cloud computing, artificial intelligence, and big data analysis. Intelligent fusion is dependent on the architecture and security features of the industrial internet. Firstly, the paper studies the infrastructure mode that needs to be solved urgently in the industrial internet and provides a possible infrastructure mode and related security evaluation system. Secondly, it analyses the digital transformation process with the case of G.E.os industrial nternet development practice. It clarifies that G.E. is forming a new value closed-loop through digital and strategy mixed channels. Thirdly, industrial internet security research is described within multiple viewpoints based on industrial internet applications, the security service and security assurance defense systemos architecture, and the non-user entrance probability model. Finally, the paper illustrates the changes in knowledge workflow and social collaboration caused by the industrial internet under intelligent manufacture.

Performance Analysis of Delay Distribution and Packet Loss Ratio for Body-to-Body Networks

With the increasing wide applications of wearable wireless networks, body-to-body networks (BBNs) have become significantly important to provide timely and reliable data delivery services. For a specific BBN, assessing its theoretically achievable Quality of Service (QoS) is necessary, especially on the key performance metrics of end-to-end delay distribution and packet loss ratio. The existing analysis models in the literature mainly focused on 1-D space scenarios. In this article, BBN in a 2-D area is considered, where mobile nodes freely and stochastically move along lanes. By introducing two new definitions: 1) node entrance probability and 2) network entrance probability, a systematically analytical framework for end-to-end delay distribution and packet loss ratio is presented. The proposed analytical framework is built on three critical techniques: 1) the Markov chain to model node behaviors; 2) the first passage theory to calculate node entrance probability and network entrance probability; and 3) the central limit theory to decrease the computation time for summing up per-hop delay. Simulation results demonstrate the effectiveness and accuracy of our proposed analysis model.

Occurrence and exposure analysis of microplastic in the gut and muscle tissue of riverine fish in Kermanshah province of Iran

This study aimed to determine the presence of MPs in the gut and muscle tissue of riverine fish collected from the Qarasu River, Kermanshah, Iran. The results highlighted that MPs were found in the gut and muscle of all fish species at an average abundance of 8.12 ± 4.26 P/individual and 0.85 ± 0.38 P/g muscles, respectively. High amounts of MPs were found in the range of 1-25 μm in terms of size distribution. The properties of MPs extracted indicated that PE, PP, PS, and PA in the monotype of fiber and fragment were the most abundant plastic types and shapes found. Additionally, EAI was calculated for MPs found in the muscle. So, 174.43 and 127.19 P/kg/bw/year (1.28 and 0.93 g/kg/bw/year), were intake by two groups of adults and children, respectively. These findings highlight the contamination of fish as a common source of marine food in home consumption and the probability of entrance into the human diet.

Research on phase diagram of traffic flow in a single loop roundabout under open boundary condition

The cellular automation traffic flow model of roundabout with inner-roundabout-lane, injection-roundabout-lane and extraction-roundabout-lane is used to study the traffic flow of single loop roundabout under open boundary conditions. Through computer simulation, the relationships between the entrance probability, exit probability, vehicle braking probability and system flow, the average speed of each lane and system in the open boundary conditions are studied.Besides, the space-time diagram of vehicles on the injection-roundabout-lane with different entrance exit probabilities and the system phase diagram are established. In the system phase diagram, the critical entry probability and exit probability values of each part of the phase diagram under different braking probability are given. The results show that the system traffic flow can be divided into three phases: the phase in which the system flow changes with the entrance probability, the phase in which the system flow changes with the exit probability, and the phase in which the system flow has nothing to do with the entrance probability and exit probability. This will provide some guidance for road management.

Lattice model for active flows in microchannels.

We introduce a one-dimensional lattice model to study active particles in narrow channel connecting finite reservoirs. The model describes interacting run-and-tumble swimmers exerting pushing forces on neighboring particles, allowing the formation of long active clusters inside the channel. Our model is able to reproduce the emerging oscillatory dynamics observed in full molecular dynamics simulations of self-propelled bacteria [Paoluzzi et al., Phys. Rev. Lett. 115, 188303 (2015)PRLTAO0031-900710.1103/PhysRevLett.115.188303] and allows us to extend in a simple way the analysis to a wide range of system parameters (box length, number of swimmers), taking into account different physical conditions (presence or absence of tumbling, different forms of the entrance probability into the channel). We find that the oscillatory behavior is suppressed for short channels length L<L^{*} and for high tumbling rates λ>λ^{*}, with threshold values L^{*} and λ^{*} which in general depend on physical parameters. Moreover, we find that oscillations persist by using different entrance probabilities, which, however, affect the oscillation properties and the filling dynamics of reservoirs.

Sexual debut and college entrance among South Korean adolescents

IntroductionFor the past few decades, numerous theoretical perspectives have predicted a negative association between adolescent sexual debut and the probability of college entrance. The present article extends the literature by using nationally representative longitudinal data from South Korea to assess these perspectives. MethodsDrawing on longitudinal data from South Korea, this article examined the impact of becoming sexually active between 8th and 12th grades on the probability of college entrance. We controlled for a wide array of confounding variables by using logit models that account for longitudinal attrition and school-based sampling design. ResultsAnalytical results showed that the initiation of sexual intercourse during adolescence predicted a statistically significant decrease in the probability of college entrance for both boys and girls. Gender-specific analyses suggested that, on average, sexual debut in adolescence was associated with a decrease of 10.3 percentage points in the probability of college entrance for boys and a decrease of 14.7 percentage points for girls. ConclusionsThese findings strongly support the theoretical perspectives of age norm theory and sexual double standards in South Korea, where strictly conservative attitudes toward sexuality and sexual behaviors are dominant.

Rainfall and population dynamics of Grey Pileated Finch Coryphospingus pileatus (Aves: Passeriformes) in a Neotropical dry forest

AbstractIn tropical dry environments rainfall periodicity may affect demographic parameters, resulting in fluctuations in bird abundance. We used capture–recapture data for the Grey Pileated Finch from a Neotropical dry forest to evaluate the hypothesis that intra‐ and inter‐annual survival, individuals entrance and population abundance, are related to local rainfall. Sampling occurred across 3 years, with individuals captured, tagged and evaluated for age and presence of brood patch every 14 days. Using the POPAN formulation, we generated demographic models to evaluate study population temporal dynamics. Best‐fit models indicated a low apparent annual survival in the first year (16%) compared to other years (between 47 and 62%), with this low value associated with an extreme drought. The abundance of juveniles at each capture occasion was significantly dependent on the accumulated precipitation in the previous 14 days, and the juvenile covariate was a strong predictor of the intra‐annual entrance probability (natality). Individuals entrance during the reproductive period corresponded to 53, 52 and 75% of total ingress for each year, respectively. The trend in sampled population size indicated positive exponential growth (Ninitial = 50, Nlast = 600), with intra‐annual fluctuations becoming progressively more intense. Low survival was relevant during population decline at study onset, while at study end intense Individuals entrance promoted rapid population growth. Thus, the indirect effects of rainfall and the combined effect of two demographic rates operated synergistically on the immediate population abundance of Grey Pileated Finch, an abundant bird in a Neotropical dry forest.

Size-dependent social attraction and repulsion explains the decision of Atlantic cod Gadus morhua to enter baited pots.

The present study tested whether the presence of already retained fishes inside baited fish pots acted as a social attraction and affected the entrance probability of Atlantic cod Gadus morhua in a fjord in northern Norway. Video analysis revealed that the probability of an entrance initially increased with the presence of low numbers of fishes inside the pot, but subsequently decreased at a critical number of caught fishes. The critical number was dependent on the size of the G. morhua attempting to enter. This demonstrates that social attraction and repulsion play a role in G. morhua pot fishing and has important implications for the capture efficiency of fisheries executed with pots.

Equilibrium joining strategies in M/M/1 Queues with working vacation and vacation interruptions

We study the equilibrium joining strategies for customers in an M/M/1 queue with working vacations and vacation interruptions. The service rate switches between a low and a high value depending on system dynamics. The server will take a multiple working vacation when the system is empty, during which a low service rate is provided to the arriving customers if any. Upon completion of the first customer’s service, given that the system is not empty, the working vacation will be terminated which means the server comes back and serves the following customers with a higher service rate. Otherwise, if the system is found empty upon completion of the first service, the server will continue his working vacation. Arriving customers may or may not know the state of the server and/or the number of the customers upon arrival, but they have to decide whether to enter the system or balk based on a linear reward-cost structure. We investigate customer behavior according to different levels of information regarding the system state. The equilibrium strategies for the customers are derived and the stationary behavior of the system under these strategies are analyzed. Finally, the effect of different levels of information on equilibrium thresholds and equilibrium entrance probabilities is illustrated by several numerical examples.

Using inverse Lz-transform for obtaining compact stochastic model of complex power station for short-term risk evaluation

In this paper a short-term risk evaluation is performed for electric power stations, where each power generating unit is presented by a multi-state Markov model. Risk is treated as the probability of loss of load or in other words, as the probability of system entrance in the set of states, where demand cannot be satisfied. The main obstacle for risk evaluation in such cases is a "curse of dimensionality" – a great number of states of entire power station that should be analyzed. Usually when the number of system states is increasing drastically, enormous efforts are required for solving the problem by using classical Markov methods or simulation techniques. Well known universal generating function technique also cannot be directly applied because this technique is primarily oriented to steady-state reliability analysis. By using such extension of UGF techniques as Lz-transform, one can find for the short-term such reliability characteristics as loss of load probability, expected energy not supplied to consumers etc. However risk function still cannot be obtained by using these techniques. This problem in many practical cases is a challenge for reliability researchers and engineers. In this paper, a special method based on inverse Lz-transform (LZ−1 transform) is developed in order to calculate risk function for such multi-state power systems. In order to illustrate the proposed approach, the short-term risk evaluation for a power station with different coal-fired generating units is presented.

Propagation of cortical spreading depression into the hippocampus: The role of the entorhinal cortex.

Propagation of cortical spreading depression (CSD) to the subcortical structures could be the underlying mechanism of some neurological deficits in migraine with aura. The entorhinal cortex (EC) as a gray matter bridge between the neocortex and subcortical regions plays an important role in this propagation. In vitro combined neocortex-hippocampus brain slices were used to study the propagation pattern of CSD between the neocortex and the hippocampus. The effects of different compounds as well as tetanic electrical stimulations in the EC on propagation of CSD to the hippocampus were investigated. Repetitive induction of CSD by KCl injection in the somatosensory cortex enhanced the probability of CSD entrance to the hippocampus via EC. Local application of AMPA receptor blocker CNQX and cannabinoid receptor agonist WIN 55212-2 in EC facilitated the propagation of CSD to the hippocampus, whereas application of NMDA receptor blocker APV and GABAA receptor blocker bicuculline in this region reduced the probability of CSD penetration to the hippocampus. Application of tetanic stimulation in EC also facilitated the propagation of CSD entrance to the hippocampus. Our data suggest the importance of synaptic plasticity of EC in filtering the propagation of CSD into subcortical structures and possibly the occurrence of concomitant neurological deficits. Synapse 68:574-584, 2014. © 2014 Wiley Periodicals, Inc.

Study on the Traffic Behavior of On-Ramp System Considering Driver Behavior

based on the main road into a two lane entrance ramp system the open boundary conditions, using the asymmetric lane changing rules, considering driver behavior characteristics, from standpoint of safety driving ,simulate the entrance ramp system. We get a basic road map different entrance probability of flow, velocity, and analyze the driving safety.compared with reference, and the reference results show that after considering driver behavior, in the ramp at the interface, reduce the interaction with the main ramp,not only the system traffic flow in each section is improved, and but also improve the driving safety.Considering the entrance ramp system driver behavior can be simulated more in line with the running state of the vehicle in real life.

Some Results on Modeling Biological Sequences and Web Navigation with a Semi Markov Chain

In the article, the entrance probabilities and the probability distribution of the number of transitions to a state are studied to provide some answers to questions related to state occupancies for the semi Markov model. Biological sequences and Web navigation are two cases that initially seem to be different but to a certain extent they do have similarities. Two main aspects of word occurrences in biological sequences are: (a) where do they occur and (b) how many times do they occur. In Web navigation the similar questions are (a) when a node is visited and (b) how many times a node is visited. So, the theoretical results of this study are applied to model these two cases and derive distributions of word location or node occurrence and frequency of occurrences. Rewards/costs are included in the Web navigation model and analytic forms for the means, variances, and moments of total interval rewards/costs are provided.

Equilibrium balking strategies in Markovian queues with working vacations

The equilibrium balking strategies are investigated in the paper for observable and unobservable single-server queues with working vacations. In such an M/M/1 queue with working vacations, the server undertakes the workload with a lower service rate rather than completely stops to work during the vacation period. Upon arrival, the customers decide whether to join or balk the queue based on observation of the queue length and the status of the server, along with the reward-cost structure of the system. Accordingly, four cases with respect to different levels of information are studied and the corresponding Nash equilibria are derived. Finally, the effect of the information levels as well as several parameters on the equilibrium threshold and equilibrium entrance probabilities is illustrated by numerical examples.

Effects of sensitive changing-lane rule on the off-ramp traffic system

Based on the NaSh model, the rules of straight movement and lane change are defined while considering the change of driving behavior under the guidance of traffic signs at ramp; besides, a traffic model with sensitive lane change under the cellular automation is proposed. Furthermore, computer numerical simulation result indicates that the procedure of sensitive lane change can effectively reduce the lane change ratio of the straight moving vehicles, thus obviously it has an inhibitory effect on unnecessary lane change; what is more, the longer the sensitive lane change zone, the more effective the inhibitory function is. However, the traffic signs at ramp cannot be set as far as possible. Lower the lane change ratio is, shorter the sensitive lane change zone needed is. The traffic signs at ramp are set with proper distance according to the lane change ratio can effectively increase systematic traffic flow as well as the critical entrance probability.

Density profiles of the exclusive queuing process

The exclusive queuing process (EQP) incorporates the exclusion principle into classic queuing models. It is characterized by, in addition to the entrance probability α and exit probability β, a third parameter: the hopping probability p. The EQP can be interpreted as an exclusion process of variable system length. Its phase diagram in the parameter space (α,β) is divided into a convergent phase and a divergent phase by a critical line which consists of a curved part and a straight part. Here we extend previous studies of this phase diagram. We identify subphases in the divergent phase, which can be distinguished by means of the shape of the density profile, and determine the velocity of the system length growth. This is done for EQPs with different update rules (parallel, backward sequential and continuous time). We also investigate the dynamics of the system length and the number of customers on the critical line. They are diffusive or subdiffusive with non-universal exponents that also depend on the update rules.