Slot Machines Research Articles

A Hybrid Scheduling Mechanism Based on Agent Cooperation Mechanism and Fair Emergency First in Smart Factory

Smart factory also known as smart manufacturing is an emerging field with the revolution of industry 4.0. With the help of all these concepts, the smart factory integrates the manufacturing assets and represents industrial networks. In this paper, we focus on integrated solutions for smart factory concerns; by proposing an efficient task management mechanism based on an efficient and resource-aware scheduling scheme named as ACM-FEF. The scheduling algorithm used for the efficient task management is hybrid of the two scheduling approaches as agent cooperation mechanism (ACM) and fair emergency first (FEF) scheduling scheme. ACM is a decentralized scheduling approach which focuses on the production maximization goals per machine, and also pays attention to the production goals of all the machine networks involved in the smart factory. FEF scheduling scheme focuses on minimizing the tasks starvation rate and maximizing the machine utilization by efficiently using the machine slots. The proposed hybrid mechanism aims to efficiently plan tasks execution, maximize machines’ resource utilization, maximize productivity, minimize production delays, efficiently handle exceptions and efficiently control smart factory actuators.

Electrical Discharge Machining using Copper Electrode made by Additive Manufacturing

In electrical discharge machining (EDM), it is important to evacuate EDM debris from the discharge gap for machining stability and accuracy. Especially in the processing of deep slots with high aspect ratio, EDM debris accumulated in the bottom of the groove often causes short circuit and false discharge, resulting in process instability. The tool electrode having micro holes for the machining fluid, which flush debris out of the discharge gap, enables efficient EDM machining of the deep slots. However, in conventional machining, it is difficult to drill high aspect ratio micro holes. Recently, the additive manufacturing (AM) technologies with the selective laser melting (SLM) method using metal powder attracts attention as a promising technique which can produce various complicated shapes efficiently. By using the AM method, it is possible to fabricate a high aspect ratio EDM electrode with micro holes inside. This paper describes the application of electrodes fabricated by the AM method to electrical discharge machining. Almost fully dense additive manufactured copper electrode (AM-Cu electrode) having more than 99.7% relative density was obtained by optimizing the laser scanning parameters for Cu-1.3mass%Cr (Cu-Cr) alloy powder. EDM properties of the AM-Cu tool electrode and the machinability of deep rib slots by using that electrode with micro holes inside were investigated. As a result, it was confirmed that EDM properties of the AM-Cu tool electrode were almost the same as those of conventional Cu tool electrode. Moreover, it was shown that use of the AM-Cu tool electrode with micro holes inside was found to shorten the processing time and improve machining accuracy significantly compared with the conventional solid Cu tool electrode.

Minimization of Cogging Torque in Axial Field Flux Switching Machine Using Arc Shaped Triangular Magnets

Axial flux permanent magnet machine (AFPMM) provides high torque characteristics at low speeds without any mechanical gears. AFPMMs have numerous applications in wind energy, electric cars, and direct drive elevator applications. These machines have low cost and improved power to weight ratio. However, single sided AFPM suffers from torque ripples because of its non-sinusoidal back emf, cogging torque, and rotor eccentricity. There are two major components of pulsating torque, namely torque ripples and cogging torque. In PM machine design, the cogging torque is a serious concern because it adds unwanted harmonics to the pulsating torque. Whereas the torque ripples cause noise and vibrations. In order to gain high efficiency, torque ripples should be minimum. The aim of this research is to design “Slotted axial field flux switching permanent magnet machine”. Mathematical models are used to design the machine and Finite element method (FEM) has been used to analyze the machine. In addition, Latin hypercube sampling (LHS) has been used to create the samples. Finally, Kriging Method is used for approximating the model and genetic algorithm has been applied to get the optimum machine. The results showed 61.8 % reduction of the cogging torque in the proposed machine model as compared to the conventional one. Moreover, the optimized model further provided 6.15 % reduction in the cogging torque as compared to the proposed one.

Study of Graphite Tool Wear in EDM with Water-based Dielectrics and EDM Oil

Using water-based dielectrics and high-energy density electrical discharge machining for titanium alloy and superalloy has shown promising economic advantages. Combined with sinking-EDM, its finishing quality can be further enhanced. However, the relatively high tool wear rates restrict the use of water-contained working fluid in sinking-EDM. As EDM is widely used for the machining of slots and holes, it is necessary to study the tool wear in these situations. In this paper, the mechanism of electrode loss is studied in 6 kinds of dielectrics, including EDM oil, WEDM working fluid, tap water, deionized water, emulsion, and polyethylene glycol solution. Two kinds of graphite materials were compared to explain the tool wear mechanism. Electrolysis consumption and discharge erosion were evaluated by experiments. The aim of this study is analyzing the effect of electrolysis and spark explosion on the performance of tool wear as well as their relation with dielectric characteristics. According to slot machining and electrode electrolysis experiments, carbon content and conductivity are regarded as the main influence factors. It is found that the dielectrics with higher carbon content can effectively reduce the tool wear in the machining process and electrolysis can lead to thinning of the electrode which makes it crumbly. This work can help compound suitable dielectrics and choose appropriate graphite electrode materials with lower tool wear in EDM machining.

A Drunken Walk in Las Vegas: Catalan Convolutions and Gambling

SummaryAs a mathematician in Las Vegas unwilling to hunt for positive-expected-value video poker machines, we know that eventually we will lose all the money we are willing to gamble. But how long will this take? Answering this seemingly simple question takes us from Catalan convolutions to generating functions as we explore a probability distribution related to a one-dimensional drunkard’s walk.

Problem gambling among homeless clinic attenders.

To examine the relationship between problem gambling and homelessness. A consecutive sample of attenders at psychiatric clinics at three inner-city homeless hostels over 8.5 years. The demographic characteristics, comorbid conditions, pathway and pattern of homelessness of those identified to have problem gambling were compared with those who did not report problem gambling. A total of 2388 individuals were seen at the clinics in the 8 years of the study, of whom 289 (12.1%) reported problem gambling, mainly on poker machines. Those with problem gambling were more likely to be male, to have been married, employed for more than a year and to have a diagnosis of mood disorder. They were less likely to have a diagnosis of psychosis. However, the combination of psychosis and problem gambling was associated with the likelihood of having their financial affairs placed under the control of the Public Trustee. The findings suggest that earlier attention to problem gambling might reduce the likelihood of becoming homeless, as well as the need for routine enquiry about gambling behaviour, measures to reduce gambling, including expert counselling, restrictions on the availability of addictive forms of gambling and assisting vulnerable individuals with money management.

'Everyone knows grandma'. Pathways to gambling venues in regional Australia.

In regional Australia, families (including children), attend community venues that contain gambling products, such as electronic gambling machines (EGMs), for a range of non-gambling reasons. However, there is a gap in research that seeks to understand how these venues may become embedded into family social practices. Drawing on Bourdieu's concepts of habitus and cultural capital, this paper aimed to explore factors that influence family decisions to attend venues and perceptions of risk associated with children's exposure to gambling products. Face-to-face qualitative interviews were conducted with 31 parents who attended community gambling venues with their children, in New South Wales, Australia. Families attended venues for three key reasons, first because of the influence of others in their social networks, second for regular social activities and third because of structural factors such as a lack of alternative, affordable, family friendly environments in their local area. Despite recognizing the harm associated with EGMs, parents distanced themselves from EGM harm with all parents perceiving venues to be an appropriate space for families. Research in this study indicates that family social practices within venues affect perceptions of risk associated with community gambling venues. The impact of these practices on longer-term health requires more investigation by public health and health promotion researchers and practitioners. Health promotion initiatives should consider identifying alternative sources of support and/or developing alternative social spaces for families in regional communities that do not contain gambling products.

An empirical investigation of wagering behavior in a large sample of slot machine gamblers

Using individual transaction gambling data from a casino, we examine the existence of positively or negatively autocorrelated betting behavior in a panel of 42,669 gamblers observed over a period of 108 consecutive days encompassing over 17 million slot machines plays. The statistical analysis suggests that gamblers increase their bet sizes significantly more after win streaks, with the largest increase occurring after three wins in a row. This increase in bet size following win streaks remains significant after variables are introduced for demographics, wealth, habit, house money effects, time spent gambling and account balance, gambling excitement, and player fixed effects. Although ultimately we cannot definitively separate out the influence of win streaks from wealth effects, increasing the amount bet following a win streak is not inconsistent with a hot hand belief that another win is more likely on the next spin.

Effect of within-session breaks in play on responsible gambling behaviour during sustained monetary losses

Rapid, continuous gambling formats are associated with higher risks for gambling-related harm in terms of excessive monetary and time expenditure. The current study investigated the effect on gambling response latency and persistence, of a new form of within-game intervention that required players to actively engage in response inhibition via monitoring for stop signals. Seventy-four experienced electronic gaming machine gamblers, with a mean age of 35.28 years, were recruited to participate in a rapid, continuous gambling task where real money could be won and lost. Participants were randomly allocated to either the control condition where no intervention was presented, or either a condition with a passive three minute break in play or a condition with a three minute intervention that required participants to engage in response inhibition. Although there was no main effect for experimental condition on gambling persistence, both interventions were effective in elevating response latency during a period of sustained losses. It was concluded that within-game interventions that create an enforced break in play are effective in increasing response latency between bets during periods of sustained losses. Furthermore, within-game interventions that require active involvement appear to be more effective in increasing response latency than standard, passive breaks in play.

Use of Self-control Strategies for Managing Gambling Habits Leads to Less Harm in Regular Gamblers.

There is little research on the control strategies used by the general public to self-manage gambling habits and avoid harmful consequences. The current study sought to identify the most common self-control strategies of people who gamble regularly, the characteristics of those who use them, and assess the effectiveness of limit-setting strategies in reducing gambling-related harm. We recruited a large sample (N = 10,054) of Canadian adults who reported gambling activity in the past 12months. Participants completed a survey that assessed gambling habits, use of control strategies including quantitative limit setting, and gambling related harm. The most common control strategies were setting predetermined spending limits, tracking money spent, and limiting alcohol consumption. The number of self-control strategies used by gamblers was positively associated with gambling involvement, annual income, problem gambling severity and playing electronic gaming machines. Approximately 45% of respondents failed to adhere to self-determined quantitative limits for spending, frequency, and time spent gambling. People who stayed within their gambling limits were less likely to report harm even after controlling for other risk factors. However, the effectiveness of remaining within one's personal spending limit decreased for those whose limits exceed $200CAN monthly. The findings support public health interventions that promote lower-risk gambling guidelines aimed at helping gamblers stay within spending, frequency and duration limits.

Connection Between Poker Playing and Problem Gambling with Sociodemographic Factors and Other Gambling Activities.

Many variables predisposing to gambling and problem gambling are already known. Yet, little is still known about the factors associated with poker, which is one of the most popular and the fastest growing areas of gambling, especially among young people. The aim of our study was to identify the relationship of selected sociodemographic factors with playing poker and problematic gambling. The other gambling activities was also included. The results of the regression analysis demonstrated that the following variables were connected with playing poker: place of residence (p < 0.001), mother's education (p = 0.004) and that of father (p = 0.046), material status, both of family of origin and current, and financial independence (p < 0.001). The risk of problem gambling is higher in case of players with low assessment of their own current material status (p = 0.028) and those who are financially dependent (p = 0.046). The risk level of problem gambling is also associated with the poker players' involvement in: slot machine games, sports betting, Totalizator Sportowy (Lotto) games, casino games (for all variables, the significance level is p < 0.001). The acquired data helped us to identify the groups most exposed to playing poker and excessive involvement in the game and may contribute to the development of appropriate prevention programs to protect persons belonging to the risk group.

Free-Spins Spur Gamblers to Quit EGMs Early: An Online EGM Study.

Free-spins on slot machines introduce a salient moment of potentially large wins that might influence people to either quit or continue a gambling session. Two theoretical models make different predictions about why people quit a gambling session. From a behaviourist perspective, people quit a session when they are either satiated or the lack of rewards lead to the extinction of behaviour. Alternatively, from a behavioural-finance perspective, people quit due to the disposition effect: a general finding whereby investors tend to sell shares or other assets when the price has increased, but keep assets that have dropped in value. From the behaviourist perspective, we predict that people experience free spins as a moment of intermittent reinforcement, which should encourage them to continue gambling longer. According to the disposition effect, however, the large win would trigger risk-aversion, signalling an opportunity to "cash out" and lock-in the gain. In the present study, 188 gamblers (72 female) were randomly allocated to one of three conditions: control, early free-spins and late free-spins, in an online EGM simulation (points only). Consistent with the disposition effect, participants who received early free-spins quit earlier, placing significantly fewer bets, than those in control condition. The study suggests that free-spins, rather than being reinforcing within session, may signal an opportunity to quit early. In the discussion, however, we speculate on whether future research could demonstrate that a perceived lack of free spins in a session may keep players engaged longer.

Quick Hits.

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Altering the availability of healthier vs. less healthy items in UK hospital vending machines: a multiple treatment reversal design

BackgroundAltering the availability of healthier or less-healthy products may increase healthier purchases, but evidence is currently limited. The current study aimed to investigate the impact of altering the absolute-and-relative availability of healthier and less-healthy products – i.e. simultaneously altering the number of options available and the proportion of healthier options – in hospital vending machines.MethodsAn adapted multiple treatment reversal design was used, altering products available in ten vending machines serving snack foods and/or cold drinks in one English hospital. Machines were randomised to one of two sequences for the seven 4-week study periods: ABCADEA or ADEABCA. In Condition A (study periods 1, 4 and 7) the proportions of healthier products were standardised across all machines, so that 25% of all snack slots and 75% of drink slots were healthier. In Condition B, 20% of vending machine slots were emptied by removing less-healthy products. In Condition C, the empty slots created in Condition B were filled with healthier products. Conditions D and E were operationalised in the same way as B and C, except healthier products were removed in D, and then less-healthy products added in E. Sales data were obtained from machine restocking records. Separate linear mixed models were conducted to examine the impact of altering availability on energy purchased (kcal) from (i) snacks or (ii) drinks each week, with random effects for vending machine.ResultsThe energy purchased from drinks was reduced when the number of slots containing less-healthy drinks was decreased, compared to standardised levels (− 52.6%; 95%CI: − 69.3,-26.9). Findings were inconclusive for energy purchased from snacks when less-healthy snack slots were reduced (− 17.2%; 95%CI: − 47.4,30.5). Results for altering the number of slots for healthier drinks or snacks were similarly inconclusive, with no statistically significant impact on energy purchased.ConclusionsReducing the availability of less-healthy drinks could reduce the energy purchased from drinks in vending machines. Further studies are needed to establish whether any effects might be smaller for snacks, or found with higher baseline proportions of healthier options.

Predicting Intention to Play Random and Skill-based Electronic Gambling Machines Using the Theory of Reasoned Action.

Hybrid gambling machines (HGMs) are a new gambling activity that combine the skill element of traditional video games with the random pay-out schedule of electronic gaming machines (e.g., slots). Developed to increase gambling by younger generations that favor video games, there is currently no empirical evidence regarding consumer views of HGMs to guide policy-decision making related to this new gambling activity. We use the theory of reasoned action (TRA) to investigate factors that motivate intentions to play these machines in two studies: (1) among 43 casino patrons and (2) among 184 US online participants residing in states where HGMs were available. Both samples completed surveys after exposure to actual or explanations of HGMs and slots. Analyses supported the prediction that positive attitudes towards HGMs and positively perceived subjective norms would predict intention to play HGMs and slots. The results suggest that the TRA is a useful framework for explaining intentions to gamble on traditional slot machines and new HGMs. The absence of research on HGMs makes these studies an important and necessary contribution to the empirical literature on machine gambling. Understanding individuals' intentions to engage with HGMs is important to guide development of harm-minimisation practices and evaluate impact of policy changes.

Encouraging Gamblers to Think Critically Using Generalised Analytical Priming is Ineffective at Reducing Gambling Biases.

Gambling has been associated with an array of fallacious beliefs that foster risky gambling decisions. Research into other belief systems suggests that the endorsement of non-evidence based beliefs, such as the paranormal or conspiracy theories, can be reduced when people think more analytically. The purpose of this study was to explore whether an intervention designed to elicit analytical thinking was effective in altering the gambling beliefs and simulated gambling behaviour of 178 regular electronic gaming machine (EGM) gamblers (102 males, 76 female). Participants were randomly allocated to complete either an analytic or a neutral priming task, followed by completion of belief measures (erroneous and protective) and play on a simulated EGM game. Results failed to show that priming for analytical thinking changed betting on an EGM; including features of bet size, bet change, persistence and theoretical losses. Contrary to expectations, results suggest that priming analytical thinking using generalised interventions does not appear to be effective in altering peoples' simulated gambling involvement or gambling beliefs. In fact, priming people to think more critically might be counterproductive by contributing to greater positive expectations about gambling outcomes. The results further suggested that the number of times a player alters their bet is a good indicator of theoretical gambling losses and is associated with irrational gambling cognitions. Interventions designed to promote safer thinking in gamblers should be implemented with care, as results from our study suggest that encouraging critical thinking in at-risk or problem gamblers may not be effective in reducing risky gambling.

Eddy Current Calculation of a High-Speed Slotted Machine With Halbach Magnetization at No-Load Condition

The eddy current and the eddy current loss in permanent magnets (PMs) are important factors in high-speed machine design and performance prediction. The eddy current loss is related to the magnetic field, the shape of magnets, and rotating speed. In this article, the eddy current is analytically calculated with a 2-D method in a high-speed machine with the Halbach magnetization. This analytical method calculates the eddy current with two parts: one part is induced by the instantaneous radial flux density and the other part is induced by instantaneous tangential flux density. The instantaneous radial and tangential flux densities are varying in the PM when the rotor rotates. The flux density in the PM is calculated by the 2-D complex relative permeance method with the SC-Toolbox aid. When the slotted machine operated at no-load condition, the eddy current is analytically calculated in this article based on the instantaneous flux density, and the eddy current distribution in the magnet is compared with the finite-element method (FEM) solutions, the comparison shows that the 2-D analytical method is an effective method for the eddy current and eddy current loss calculation. In the slotted machine with the Halbach magnetization, the eddy current loss increases with the arc angle of the main segment magnet increases, the eddy current loss increases fast at high speeds and cannot be ignored, but Halbach magnetization can reduce it in the high-speed machine as long as the magnetization parameters are chosen properly.

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Sheet cathode design and experimental study on the electrochemical machining of deep narrow slots in TB6 titanium alloy

TB6 titanium alloy is extensively applied in lightweight vehicles, biomedicine, and other domains because of its high specific strength, excellent fracture toughness, and excellent corrosion resistance. Electrochemical machining is a non-contact processing technology that has significant advantages in processing materials that are difficult to cut, such as cemented carbide, high-temperature alloys, and titanium alloys. To improve the consistency of deep narrow slots fabricated in TB6 titanium alloy via electrochemical machining, a sheet cathode design and experimental studies were carried out in this work. Based on a unidirectional fluid–structure coupling simulation, the influence of the stiffener arrangement on the cathode rigidity and flow-velocity distribution was studied. Furthermore, by modifying the geometry of the stiffener, the cathode deformation was significantly reduced, and flow-velocity uniformity at the cathode outlet was improved. The influence of a superimposed low-frequency oscillation on the gap distribution and the profile error of a deep narrow slot was investigated experimentally. The results revealed that when an applied voltage of 24 V, an oscillation frequency of 50 Hz, and an amplitude of 0.05 mm were adopted, a highly homogeneous deep narrow slot with an entrance gap of 0.24 mm and a side gap of 0.33 mm was machined into the TB6 titanium alloy.

Towards an Improved Strategy for Solving Multi-Armed Bandit Problem

Multi-Armed Bandit (MAB) problem is one of the classical reinforcements learning problems that describe the friction between the agent’s exploration and exploitation. This study explores metaheuristics as optimization strategies to support Epsilon greedy in achieving an improved reward maximization strategy in MAB. In view of this, Annealing Epsilon greedy is adapted and PSO Epsilon greedy strategy is newly introduced. These two metaheuristics-based MAB strategies are implemented with input parameters, such as number of slot machines, number of iterations, and epsilon values, to investigate the maximized rewards under different conditions. This study found that rewards maximized increase as the number of iterations increase, except in PSO Epsilon Greedy where there is a non-linear behavior. Our Annealing-Epsilon greedy strategy performed better than Epsilon Greedy when the number of slot machines is 10, but Epsilon greedy did better when the number of slot machines is 5. At the optimal value of Epsilon, which we found at 0.06, Annealing Epsilon greedy performed better than Epsilon greedy when the number of iterations is 1000. But at number of iterations ≥ 1000, Epsilon greedy performed better than Annealing Epsilon greedy. A stable reward maximization values are observed for Epsilon greedy strategy within Epsilon values 0.02 and 0.1, and a drastic decline at epsilon &gt; 0.1.