Multiple Schedule Research Articles

EFECTOS DE L A S INSTRUCCIONES ENUNCIADA S POR EL E XPERIMENTADOR Y EL PARTICIPANTE EN L A EJECUCIÓN DE UN PROGRAMA EN HUMANOS

The experiment examined effects of instructions on human schedule performance when providers of the instructions were persons other than the experimenter. Pressing a key by one member of each pair of eight undergraduates produced points on a multiple fixed-interval (FI) FI schedule.Another member of the pair was exposed to a multiple fixed-ratio (FR) differential-reinforcement-of-low-rate (DRL) schedule. After every session, verbal descriptions of how to increase points written by another member of the pair were presented.The final response rates under the multiple FI FI schedule were indistinguishable between the two components in each of four participants although they each received verbal descriptions indicating that the way to increase points with the key was to respond rapidly in one component and to respond slowly in another. Such weak effects of instructions given from persons other than the experimenter were contrasted with stronger effects of instructions given by the experimenter, that is, the final response rates were higher with the instruction to respond rapidly than with the instruction to respond slowly for three of the four participants.This differential effect across the instruction providers was not found in each of four participants who were exposed to the multiple FR DRL schedule.

INTERAÇÕES COMPORTAMENTAIS EM ESQUEMA MÚLTIPLO UTILIZANDO O JATO DE AR QUENTE (JAQ) COMO ESTÍMULO PUNIDOR

Interação comportamental é um fenômeno que pode ocorrer em esquemas múltiplos, em que a taxa de respostas em um componente pode mudar em função de alteração do esquema de reforçamento ou de punição no segundo componente. Interações comportamentais podem ocorrer quando há utilização de contingências apetitivas ou aversivas, como punição. Com relação às contingências punitivas, existem dados conflitantes na literatura sobre a produção de contraste ou indução com não humanos, utilizando majoritariamente choque elétrico como estímulo punidor. O objetivo deste estudo foi verificar se ocorreria algum tipo de interação comportamental em esquemas múltiplos, utilizando o jato de ar quente (JAQ) como estímulo punidor. Dezesseis ratos albinos foram expostos às fases: Pré-Punição, Punição e Pós-Punição. Nas três fases vigorou um esquema múltiplo com dois componentes (claro e escuro). O esquema de reforçamento em vigor em ambos os componentes foi intervalo variável 30s (VI 30) para respostas de pressão à barra, em todas as fases. Na fase punição, o JAQ foi administrado contingente a cada resposta de pressão à barra no componente claro para metade dos sujeitos, e no escuro para a outra metade. Ocorreu indução negativa no componente não punido, para todos os sujeitos, principalmente nas sessões iniciais; ao longo das sessões, ocorreu recuperação na taxa nesse componente para todos os sujeitos, resultando em ocorrência tardia de contraste positivo para três dos sujeitos. A produção de contraste parece estar relacionada ao número de sessões de exposição ao punidor.Palavras-chave: interação comportamental, punição, contraste, indução.

An individualized method for establishing and thinning multiple schedules of reinforcement following functional communication training

Using multiple schedules of reinforcement following functional communication training (FCT) can produce discriminated mands while maintaining low rates of problem behavior (Fisher et al., 1998; Hanley et al., 2001). A review of this literature (Saini et al., 2016) noted the absence of a method for systematically determining the duration of reinforcement (SD) and extinction (SΔ) components in such multiple-schedule arrangements. The same review also suggested that introducing a momentary differential-reinforcement contingency could aid in producing discriminated mands by eliminating the possibility of adventitious reinforcement. The current investigation attempted to evaluate these two recommendations by altering the durations of SD and SΔ components of a multiple schedule based on participants’ response patterns during treatment. Specifically, we (a) yoked the duration of the initial SΔ component to the rate of mands during FCT and (b) introduced a delay to the SD following instances of problem behavior. All five participants exhibited discriminated mands. In addition, mands maintained for all five participants, and problem behavior remained low for four participants when the schedule of reinforcement was systematically thinned.

Increasing sharing in children with autism spectrum disorder using automated discriminative stimuli

Appropriate sharing of a high-preference item is a common problem among children with autism spectrum disorder (Baron-Cohen et al., 1985). The purpose of the current study was to evaluate whether a multiple schedule of reinforcement could be used to promote appropriate turn-taking behavior. Participants included one dyad of siblings and one dyad of non-related peers who were identified as having poorly developed sharing skills. The first dyad included a 6-year-old diagnosed with autism and his typically developing sister. The other dyad included a 4-year-old and 5-year-old, both diagnosed with autism. During sessions, an auditory and visual stimulus in the form of a PowerPoint® presentation played in the background to signal each participant’s turn with a mutually preferred item. Following baseline, we used a progressive prompt delay to teach the participants to attend and appropriately respond to the stimuli presented in the PowerPoint® presentation. Findings suggest that an auditory and visual stimulus can be used to increase appropriate sharing.

Highlights of This Issue

Since the failure of matrix metalloproteinase (MMP) inhibitor in clinical trials, highly selective reagents that target individual MMPs have been the new focus. MMP-2 is highly expressed in bone metastatic breast cancer and drives the progression of the disease. Here, Tauro and colleagues have generated MMP-2 highly selective bone seeking MMP inhibitors (BMMPIs) based on bisphosphonates. In vivo studies reveal BMMPIs are effective in promoting the apoptosis of bone metastatic breast cancer cells and protecting against cancer induced bone disease. Given the well-tolerated nature of bisphosphonates, BMMPIs could be rapidly translated to the clinic for the treatment of skeletal malignancies such as bone metastatic breast cancer.Immune checkpoint blockade has shown promise in melanoma, with a subset of patients experiencing complete durable responses. However, the majority of patients still do not receive long-term benefit. Farren and colleagues combined immune checkpoint blockade with selinexor, a small molecule inhibitor of exportin-1 that has anti-melanoma activity of its own. This treatment combination skewed immune responses toward a Th1 type, and proved more effective in controlling tumor growth when administered at multiple schedules in a murine model. These results support further development of this novel combination of immune checkpoint blockade and small molecule nuclear export inhibitors.Selinexor (KPT-330) is a first in class nuclear transport inhibitor currently in clinical trials as an anti-cancer agent. Tyler, Servos and colleagues analyzed immune homeostasis in mice treated with selinexor and found disruptions in T cell development, a progressive loss of CD8 T cells and increases in inflammatory monocytes. Altering the frequency of drug dosing preserved normal immune function better than decreasing the dose. Overall, selinexor treatment leads to transient inhibition of T cell activation but clinically relevant once and twice weekly dosing schedules that incorporate sufficient drug holidays allow for normal CD8 T cell functioning and development of anti-tumor immunity.Stage III/IV head-and-neck squamous cell carcinomas (HNSCCs) are often treated with cisplatin-containing chemoradiation protocols. However, not all tumors respond well and biomarkers to personalize chemoradiotherapy are not available. Martens-de Kemp and colleagues performed an unbiased genome-wide functional genetic screen to identify genes that influence cisplatin response. Pathway analysis on cisplatin-sensitizing genes identified the FA/BRCA pathway as the predominant cisplatin response pathway in HNSCC cells. Expression of genes involved in this pathway predicted prognosis of (chemo-) radiation treated HNSCC patients. Biomarkers that indicate FA/BRCA pathway activity in tumors are prime candidates to predict cisplatin response in HNSCC.

No impact of repeated extinction exposures on operant responding maintained by different reinforcer rates

Greater rates of intermittent reinforcement in the presence of discriminative stimuli generally produce greater resistance to extinction, consistent with predictions of behavioral momentum theory. Other studies reveal more rapid extinction with higher rates of reinforcers – the partial reinforcement extinction effect. Further, repeated extinction often produces more rapid decreases in operant responding due to learning a discrimination between training and extinction contingencies. The present study examined extinction repeatedly with training with different rates of intermittent reinforcement in a multiple schedule. We assessed whether repeated extinction would reverse the pattern of greater resistance to extinction with greater reinforcer rates. Counter to this prediction, resistance to extinction was consistently greater across twelve assessments of training followed by six successive sessions of extinction. Moreover, patterns of responding during extinction resembled those observed during satiation tests, which should not alter discrimination processes with repeated testing. These findings join others suggesting operant responding in extinction can be durable across repeated tests.

Combining multiple schedules of reinforcement with glutamate biosensors to examine the effects of cocaine and food on prelimbic glutamatergic signaling in freely-moving rats

Combining multiple schedules of reinforcement with glutamate biosensors to examine the effects of cocaine and food on prelimbic glutamatergic signaling in freely-moving rats

Escape from rich-to-lean transitions: Stimulus change and timeout.

Extended pausing during discriminable transitions from rich-to-lean conditions can be viewed as escape (i.e., rich-to-lean transitions function aversively). In the current experiments, pigeons' key pecking was maintained by a multiple fixed-ratio fixed-ratio schedule of rich or lean reinforcers. Pigeons then were provided with another, explicit, mechanism of escape by changing the stimulus from the transition-specific stimulus used in the multiple schedule to a mixed-schedule stimulus (Experiment 1) or by producing a period of timeout in which the stimulus was turned off and the schedule was suspended (Experiment 2). Overall, escape was under joint control of past and upcoming reinforcer magnitudes, such that responses on the escape key were most likely during rich-to-lean transitions, and second-most likely during lean-to-lean transitions. Even though pigeons pecked the escape key, they paused before doing so, and the latency to begin the fixed ratio (i.e., the pause) remained extended during rich-to-lean transitions. These findings suggest that although the stimulus associated with rich-to-lean transitions functioned aversively, pausing is more than simply escape responding from the stimulus.

Exploring Scheduling Effects on Task Performance with TaskInsight

The complex memory hierarchies of nowadays machines make it very difficult to estimate the execution time of the tasks as depending on where the data is placed in memory, tasks of the same type may end up having different performance. Multiple scheduling heuristics have managed to improve performance by taking into account memory-related properties such as data locality and cache sharing. However, we may see tasks in certain applications or phases of applications that take little or no advantage of these optimizations. Without understanding when such optimizations are effective, we may trigger unnecessary overhead at runtime level. In previous work, we introduced TaskInsight, a technique to characterize how the memory behavior of the application is affected by different task schedulers through the analysis of data reuse across tasks. We now use this tool to dynamically trace the scheduling decisions of multithreaded applications through their execution and analyze how memory reuse can provide information on when and why locality-aware optimizations are effective and impact performance. We demonstrate how we can detect particular scheduling decisions that produced a variation in performance, and the underlying reasons when applying TaskInsight to several of the Montblanc benchmarks. This flexible insight is key both for the programmer and runtime to allow assigning the optimal scheduling policy to certain executions or phases.

A load balance oriented cost efficient scheduling method for parallel tasks

With the development of Internet technology, distributed task processing has become the key to solve the problems in big data computing, cloud computing, and collaborative computing. At the aspect of distributed task scheduling optimization, it is needed to establish the scheduling architecture with multiple schedulers, to meet the requirement of minimizing the cost of large scale parallel tasks. However the schedulers would give rise to the issue of high device load, intensive resource competition, and the inefficient collaboration. For this, we proposed the CESM (Cost Efficient Scheduling Method) method, which utilizes the weighted random schedule policy to assign the devices to the tasks, to reduce the competition of the task on the efficient low-cost devices. The weights in the random schedule process dependent on the scheduling environment, such as communication time, the busy state, the execution time and the cost. The efficient low-cost device tends to get a higher weight, implying it has a higher possibility to be assigned. That makes the scheduling results have a better rationality on execution time and cost. For this reason, we designed the weight model based on the communication time, the busy state, the execution time and the cost, and adopted the experimental method to analyze the values of the parameters. Finally, we gave four experiments on the arrival time test, device dependence test, task structure test, device set test, respectively, to verify the effectiveness and rationality of the proposed CESM.

Evaluating Treatments for Functionally Equivalent Problem Behavior Maintained by Adult Compliance with Mands During Interactive Play

A primary goal of behavioral interventions is to reduce dangerous or inappropriate behavior and to generalize treatment effects across various settings. However, there is a lack of research evaluating generalization of treatment effects while individuals with functionally equivalent problem behavior interact with each other. For the current study, the severe problem behavior of two participants with developmental disabilities was targeted for assessment and treatment. Results of a functional analysis indicated that for both participants, problem behaviors occurred when destructive behavior produced reinforcement of participant mands . The use of a multiple schedule that alternated between differential reinforcement of other behaviors and differential reinforcement of alternative behavior (mands) was sufficient to produce a significant reduction in problem behavior for one participant; the addition of differential reinforcement of alternative behaviors via compliance was necessary for the second participant. Extended treatment sessions, which focused on interaction between the two participants, involved one therapist concurrently implementing each participant’s treatment while they were directed to play with one another (a situation that previously evoked problem behavior). Results show that each participant’s treatment produced low to zero rates of problem behavior even during extended interactions.

Omission Training Results in More Resurgence than Alternative Reinforcement

Resurgence refers to the reemergence of a previously reinforced response following the extinction of a more recently reinforced response. In a published study, resurgence occurred to a lesser extent following differential reinforcement of alternative behavior (DRA) than differential reinforcement of other behavior (DRO) with pigeons, but this effect has not been replicated with humans. We conducted a within-subject comparison of resurgence following DRA and DRO, using a human-operant preparation. Six college students earned points by clicking a mouse button across two-component multiple schedules. During both baseline components, points were delivered for the first click to a black circle after 2 s. Responding on the black circle decreased during the second phase, using a DRA in one component and a DRO in the other component. We tested for resurgence by terminating point deliveries (extinction) during both components in the third phase. For three of the participants, more resurgence occurred in the component previously associated with DRO than the component previously associated with DRA. The other three participants showed more resurgence in the first component experienced during extinction, regardless of whether that component was associated with DRA or DRO. However, resurgence was exacerbated when the first component during extinction was DRO rather than DRA. Although sequence influenced resurgence, DRA may be preferable to DRO as an intervention when resurgence is a concern.

Evidence for positive, but not negative, behavioral contrast with wheel-running reinforcement on multiple variable-ratio schedules

Rats responded on a multiple variable-ratio (VR) 10 VR 10 schedule of reinforcement in which lever pressing was reinforced by the opportunity to run in a wheel for 30s in both the changed (manipulated) and unchanged components. To generate positive contrast, the schedule of reinforcement in the changed component was shifted to extinction; to generate negative contrast, the schedule was shifted to VR 3. With the shift to extinction in the changed component, wheel-running and local lever-pressing rates increased in the unchanged component, a result supporting positive contrast; however, the shift to a VR 3 schedule in the changed component showed no evidence of negative contrast in the unaltered setting, only wheel running decreased in the unchanged component. Changes in wheel-running rates across components were consistent in showing a compensation effect, depending on whether the schedule manipulation increased or decreased opportunities for wheel running in the changed component. These findings are the first to demonstrate positive behavioral contrast on a multiple schedule with wheel running as reinforcement in both components.

WCTT bounds for MPI primitives in the PaterNoster NoC

This paper applies several variants of application independent time-division multiplexing to MPI primitives and investigates their applicability for different scopes of communication. Thereby, the scopes are characterized by the size of the network-on-chip, the number of participating nodes and the message size sent to each receiver or received from each sender, respectively. The evaluation shows that none of the observed variants feature the lowest worst-case traversal time in all situations. Instead there are multiple schedule variants which each perform best in a different scope of communication parameters.

Stimulus–reinforcer relations established during training determine resistance to extinction and relapse via reinstatement

The baseline rate of a reinforced target response decreases with the availability of response-independent sources of alternative reinforcement; however, resistance to disruption and relapse increases. Because many behavioral treatments for problem behavior include response-dependent reinforcement of alternative behavior, the present study assessed whether response-dependent alternative reinforcement also decreases baseline response rates but increases resistance to extinction and relapse. We reinforced target responding at equal rates across two components of a multiple schedule with pigeons. We compared resistance to extinction and relapse via reinstatement of (1) a target response trained concurrently with a reinforced alternative response in one component with (2) a target response trained either concurrently or in separate components from the alternative response across conditions. Target response rates trained alone in baseline were higher but resistance to extinction and relapse via reinstatement tests were greater after training concurrently with the alternative response. In another assessment, training target and alternative responding together, but separating them during extinction and reinstatement tests, produced equal resistance to extinction and relapse. Together, these findings are consistent with behavioral momentum theory-operant response-reinforcer relations determined baseline response rates but Pavlovian stimulus-reinforcer relations established during training determined resistance to extinction and relapse. These findings imply that reinforcing alternative behavior to treat problem behavior could initially reduce rates but increase persistence.

Energy-efficient heterogeneous resource management for wireless monitoring systems

Abstract Various energy-saving designs have been proposed for reducing the power consumption of processors through dynamic voltage and frequency scaling (DVFS). When dynamic random access memory (DRAM) or peripheral power consumption is high, dynamic power management (DPM) can be adopted to dynamically activate or deactivate devices or to switch them into energy-saving states during idle periods. This paper proposes a heterogeneous resource management mechanism to manage device scheduling for multiple tasks and task scheduling in a processor. A wireless network monitoring system was analyzed as a case study, wherein a resource sharing mechanism was developed for managing the scheduling of multiple wireless adapters, and the concept of instantaneous utilization was leveraged to enable chain-based task scheduling. This paper explores DVFS and DPM energy saving techniques for peripherals and a processor by considering both the required device time and processor time for each task without violating performance requirements under constraints of buffer size. The proposed algorithms were then implemented on a wireless network monitoring system and real traces were collected from a laboratory and downloaded from the UMass Trace Repository for use as inputs. A series of experiments was conducted to evaluate the quality of our algorithms for energy saving within the constraints of system performance requirements and hardware resources.

Scheduling Crash Tests at Ford Motor Company

We consider the problem of scheduling crash tests for new vehicle programs at Ford. We describe the development of a comprehensive web-based system that automates time-consuming scheduling analyses through mathematical optimization, while also institutionalizing expert knowledge about the engineering complexities of crash testing. We present a novel integer programming model and a corresponding solution algorithm that quickly generates efficient schedules. The system’s user interface enables engineers to specify key program data and consider multiple scheduling scenarios, while using the underlying optimization model and solution algorithms as a black box.

Energy-aware decision support for production scheduling

Manufacturing companies are forced to become energy-aware under the pressure of energy costs, legislation and consumers' environmental awareness. Production scheduling remains a critical decision making process, although demanding in computational terms and sensitive on data availability and credibility. Hence the interest in incorporating energy-related aspects in production scheduling. We propose a decision support system (DSS), composed by an Iterated Local Search algorithm that offers hierarchical optimization over multiple scheduling objectives and is energy-aware in terms of both the constraints incorporated and the objectives to be optimized, plus a generic yet concise data model whose entities are extracted from the literature and actual user requirements. The use of this DSS by two textile manufacturers shows that it supports efficiently energy-aware scheduling decisions.

Heart Rate Assessment and Use of a Multiple Schedule Treatment for an Individual with Obsessive Compulsive-like Behavior

Repetitive behavior is displayed by individuals with Autism Spectrum Disorder and those with Obsessive Compulsive Disorder (American Psychiatric Association 2013). Clinicians assessing individuals with autism who display stereotypic behavior face the challenge of determining whether or not these repetitive behaviors are more reflective of topographies observed in individuals with developmental delays, or are more representative of those observed in OCD. The distinction is important because traditional treatments for OCD have addressed the discomfort associated with repetitive acts, which has been described as a building urge that precedes compulsive behavior. In contrast, treatments for stereotypic behavior in children with autism may involve signaled periods of access to repetitive behavior which could inadvertently lead to a child encountering conditions which elicit stress as part of a treatment approach. One potential way to capture a building state of distress in a client with repetitive behavior is through the measurement of heart rate. The current study evaluated heart rate variability during conditions in which an establishing operation was either present or absent for the arranging behavior of a child with autism, as well as when access to arranging was allowed. When significant differences were not observed across these conditions, a multiple schedule treatment for arranging was implemented and demonstrated to be an effective way to manage the participant’s compulsive behavior. The treatment was implemented in the home setting and the participant’s parent was also able to demonstrate the ability to effectively implement the intervention.

Joint Routing and Links Scheduling in Two-Tier Multi-Hop RF-Energy Harvesting Networks

This letter considers a two-tiered multi-hop RF-harvesting network comprising of wireless routers and so called eh-nodes that harvest energy from RF emitted by the said routers. Our aim is to derive the shortest possible superframe or time division multiple access schedule for use by routers, which are responsible for meeting flow and energy demands. We present a linear program to derive the optimal schedule whilst satisfying the said demands. We also outline a heuristic algorithm called Algo-TS to generate transmission sets. Our results show Algo-TS produces superframes that are at most 2% longer than the optimal solution in all tested scenarios.