Most research on production planning and control (PPC) focuses on control structures, mathematical models, and algorithms, without explicitly considering human behavior. To consider a behavioral ...perspective of the PPC concept of workload control (WLC), we conduct a laboratory experiment. The study’s aim is to investigate the effects of changing workload norms, the influence of feedback information, and coworker queue length information on operators’ reaction behavior. To do so, we perform an assessment across two dimensions: operators’ (i) performance and (ii) arousal level. We contribute to the literature on endogenous processing times and highlight the importance of considering behavioral aspects when companies define an implementation strategy and when conducting WLC studies. Furthermore, given that production systems are operated by people, our results show that behavioral effects need to be considered in the specification of workload norms. Based on our results, we conclude that operators exhibit substantial heterogeneity in their reaction behavior, depending on their positioning in a flow shop (gateway station vs. downstream station).
•Laboratory experiments to investigate the interactions between a WLC system and human aspects.•Enables the observation of human behavioral effects within a flow shop system.•Assessment of operators’ reaction behavior across the two dimensions (i) performance and (ii) arousal level.•Relevance of endogenous processing times for the determination of workload norms.•Results show substantial heterogeneity in the operators’ reaction behavior, depending on whether they are in the role of a gateway station or a downstream station.
Various theories of social behavior propose that individuals condition actions that involve a moral value by following each other’s behavior. The theoretical and experimental instruments employed to ...evaluate this conditioning often focus only on the diffusion of actions with negative moral value (e.g., dishonesty, norm violation, tax evasion). In this paper, we develop and execute a laboratory experiment to study the diffusion of actions with both, positive and negative moral values. We use a lying paradigm and introduce a novel methodology operationalizing beliefs as intention proxies to study the switch between honesty and dishonesty in simultaneous and sequential move sequences. The results indicate asymmetries; while lying is strongly contagious, truth-telling is weakly so.
•Laboratory experiment studying the transmission of honesty and dishonesty.•Methodological novelty of elicited beliefs serving as intended action proxies.•Focus on the switch from intended actions to observed actions.•Asymmetries identified.•Lying is strongly contagious, while truth-telling has a weaker effect.
We conduct a laboratory experiment in which participants can make donations to real charities. We vary whether the experimenter provides matching funds for any such donations, and whether there is ...individual or team competition for these matching funds. Our results indicate that providing matching funds for all donations does increase donations from 23% to 33% of the endowment. While individual competition for matching funds had nearly the same effectiveness as matching all donations, by far the most effective approach was to form (anonymous) teams that competed for matching funds; this led to donations of 47% of the endowment. We appeal to the notion of group identity to explain our results—participants seemed to be reluctant to “let down their team” in a competition. Our results can be seen as providing support for the notion that combining group identity and competition creates a motivation that can potentially be harnessed effectively for prosocial purposes.
This paper was accepted by Uri Gneezy, behavioral economics.
When ice forms on lakes, dissolved salts are rejected, which can lead to under‐ice salt finger formation. We performed a series of laboratory experiments to visualize these fingers. While we detected ...salt fingers in our camera recordings, the signal of these fingers is nearly absent in the temperature record. We quantify the velocity of the salt‐plumes and measure the bottom salinity increase from these fingers. Further, we estimate that the salinity is often distributed evenly with depth. Comparing the salt fluxes in our experiments with a typical salt flux in lakes, we suggest that conditions are favorable for salt fingering in most seasonally ice‐covered lakes.
Plain Language Summary
When ice forms on the surface of lakes, dissolved salts are expelled from the ice into the liquid water below. If enough salt is rejected from the ice, the excess weight of the salt can lead to long “fingers” of salty fluid moving from the ice into the water below. We ran a series of experiments to investigate these “fingers”, and conclude that this process likely occurs in most freshwater lakes that freeze annually. This process is important for the evolution of lakes and will change as fewer lakes freeze.
Key Points
Cryoconcentration produces gradients in solutes under the ice in freshwater lakes
Laboratory experiments indicate that salt fingers, enabled by contrasting gradients in solutes and temperature, may be common in ice‐covered lakes
Salt fingers may not obviously perturb the temperature stratification
Beliefs about Gender Bordalo, Pedro; Coffman, Katherine; Gennaioli, Nicola ...
The American economic review,
03/2019, Letnik:
109, Številka:
3
Journal Article
Recenzirano
Odprti dostop
We conduct laboratory experiments that explore how gender stereotypes shape beliefs about ability of oneself and others in different categories of knowledge. The data reveal two patterns. First, ...men’s and women’s beliefs about both oneself and others exceed observed ability on average, particularly in difficult tasks. Second, overestimation of ability by both men and women varies across categories. To understand these patterns, we develop a model that separates gender stereotypes from misestimation of ability related to the difficulty of the task. We find that stereotypes contribute to gender gaps in self-confidence, assessments of others, and behavior in a cooperative game.
A concise review is given on the past two decades’ results from laboratory experiments on collisionless magnetic reconnection in direct relation with space measurements, especially by the ...Magnetospheric Multiscale (MMS) mission. Highlights include spatial structures of electromagnetic fields in ion and electron diffusion regions as a function of upstream symmetry and guide field strength, energy conversion and partitioning from magnetic field to ions and electrons including particle acceleration, electrostatic and electromagnetic kinetic plasma waves with various wavelengths, and plasmoid-mediated multiscale reconnection. Combined with the progress in theoretical, numerical, and observational studies, the physics foundation of fast reconnection in collisionless plasmas has been largely established, at least within the parameter ranges and spatial scales that were studied. Immediate and long-term future opportunities based on multiscale experiments and space missions supported by exascale computation are discussed, including dissipation by kinetic plasma waves, particle heating and acceleration, and multiscale physics across fluid and kinetic scales.
We use a laboratory experiment with a focus on communication frequency and content to explore social learning. The experiment varied group composition by ability and included a randomized information ...treatment. We examine how information about own and peers’ abilities affects communication frequency and content, and assess how perceptions about own and others’ abilities correlates with advice taking. We find that knowing group members’ abilities reduces the need for communication and recognizing others’ abilities correlates with how much advice participants take. This suggests that benefits of social learning depend on group ability structures and the opportunity to communicate with one another.
•Communication plays an important role in assessing the abilities of others.•Knowing peers’ abilities reduces the need for communication.•Learning about own and others’ abilities correlates with advice taking.
We report on the search for spectral irregularities induced by oscillations between photons and axion-like particles (ALPs) in the gamma-ray spectrum of NGC 1275, the central galaxy of the Perseus ...cluster. Using 6 years of Fermi Large Area Telescope data, we find no evidence for ALPs and exclude couplings above 5 times 10 (sup -12) per gigaelectronvolt for ALP masses less than or approximately equal to 0.5 apparent magnitude (m (sub a)) less than or approximately equal to 5 nanoelectronvolts at 95 percent confidence. The limits are competitive withthe sensitivity of planned laboratory experiments, and, together with other bounds, strongly constrain thepossibility that ALPs can reduce the gamma-ray opacity of the Universe.
The design and operation of an inverted cone, scalable vapor condenser, drawing cooling air from beyond the boundary layer and optionally working as a part of a gastight setup, are described and ...discussed. Besides its main use as a reflux condenser, it can also be used in one-plate distillations.
Here we present novel cave-analogue experiments directly investigating stable carbon and oxygen isotope fractionation between the major involved species of the carbonate system (HCO3−, CO2, CaCO3 and ...H2O). In these experiments, which were performed under controlled conditions inside a climate box, a thin film of solution flew down an inclined marble or glass plate. After different distances of flow and, thus, residence times on the plate, pH, electrical conductivity, supersaturation with respect to calcite, precipitation rate as well as the δ18O and δ13C values of the dissolved inorganic carbon (DIC) and the precipitated CaCO3 were obtained.
Progressive precipitation of CaCO3 along the plate is accompanied by degassing of CO2 and stable isotope fractionation, and the system is driven out of isotope equilibrium. We observe a strong enrichment of the δ13C values with increasing residence time and a smaller enrichment in δ18O. The temporal evolution of the δ18O and δ13C values of both the DIC and the precipitated CaCO3 can be explained by a Rayleigh fractionation model, but the observed enrichment in δ13C values is much larger than expected based on isotope equilibrium fractionation factors.
Our setup enables to determine the fractionation between CaCO3 and HCO3−, i.e., εCaCO3/HCO3−. Carbon isotope fractionation, 13εCaCO3/HCO3−, is strongly negative for all experiments and much lower than equilibrium isotope fractionation (0–1‰). In addition, 13εCaCO3/HCO3− decreases with increasing residence time on the plate, and thus decreasing supersaturation with respect to calcite. Thus, isotope fractionation depends on precipitation rate and consequently occurs under kinetic conditions. This is in contrast to previous studies, which found no rate-dependence and no or even a positive carbon isotope fractionation between CaCO3 and HCO3−. Oxygen isotope fractionation, 18εCaCO3/HCO3−, is also negative and dependent on precipitation rate. Since no literature values for 18εCaCO3/HCO3− are available, we calculated 18εCaCO3/HCO3− using equilibrium oxygen isotope fractionation factors between water and calcite and water and HCO3−, respectively. At the beginning of the plate, the fractionation is in agreement with the fractionation calculated using fractionation factors determined in cave systems.
The observed fractionation between CaCO3 and water, 1000ln18α, is also in good agreement with the values determined in cave systems and shows a very similar temperature dependence 1000ln18α=16.516±1.267∗103T−26.141±4.356. However, with progressive precipitation of CaCO3 along the plate, the system is forced out of isotope equilibrium with the water, and 1000ln18α increases.
The large, negative, rate-dependent isotope fractionations observed in this study suggest that precipitation of speleothem calcite is strongly kinetically controlled and may, thus, have a large effect on speleothem δ18O and δ13C values. Since these values may erroneously be interpreted as reflecting changes in past temperature, precipitation and/or vegetation density, these results have important implications for paleoclimate reconstructions from speleothems.
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