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121.
The aim of this paper is to present a dynamic goal programming scheme. Throughout the revised literature, most of the dynamic goal programming approaches use target values on the final value of the objective functionals. In this paper, dynamic target values are assumed, so that they control not only the final values of the corresponding functionals, but their evolution along the planning period. As a result, the scalar problems are also dynamic ones, where the evolution of the deviation variables is minimized. A lexicographic dynamic goal programming algorithm is developed on these basis, and some considerations are made on the efficiency of the final solutions. © 1998 John Wiley & Sons, Ltd.  相似文献   
122.
The present study examined whether resurgence of a previously reinforced target response upon removing alternative reinforcement would be greater when (1) returning to the original training context (ABA context changes) versus (2) remaining in the analogue treatment context in which the alternative response was differentially reinforced (ABB context changes). Experiment 1 arranged reinforcement of button pressing with points exchangeable for money in university students. Experiment 2 arranged reinforcement of lever pressing with food for rats. Experiment 3 arranged reinforcement of responses to a touchscreen with small bites of food with children diagnosed with ASD. Overall, resurgence of target responding tended to be greater when returning to the original training context (A) than when remaining in the analogue treatment context (B). These findings suggest context changes with differential reinforcement treatments could exacerbate the recurrence of problem behavior resulting from reductions in treatment integrity through failure to reinforce appropriate behavior.  相似文献   
123.
This research examines others’ perception of the influence of managers working in successful or unsuccessful companies who possess or lack status (to be respected by others) and power (control of valued resources). Study 1 shows that high‐status managers were judged as more influential in the firm than their low‐status peers, regardless of the company's situation. Study 2 finds that in a context of economic uncertainty, a manager with high status and power is perceived to be more capable of affecting the firm. The effect of power seems to be secondary since when a manager has low status, having high power does not significantly benefit the influence attributed to him or her. Furthermore, dominance (assertive behavior), not warmth, mediated the relationship between status and the attributed influence. Overall, these findings confirm that status is a very potent source of social influence, status and power are distinct constructs with different effects, and dominance rather than warmth is a key personal dimension linked to successful leadership.  相似文献   
124.
The effects of pressure on the mechanical and dynamical stability of NaAlSi have been fully investigated by first-principles calculations within the generalised gradient approximation (GGA). The obtained results show that the optimised lattice constants, atomic positions and elastic constants at ambient pressure are in good agreement with the available experimental and theoretical data. The lattice constants decrease monotonically with increasing pressure. The elastic constant C11, C12, C13, C33 and C66 increase while C44 decreases with increasing pressure. It is found that NaAlSi is mechanically unstable when the pressure is above 25.97?GPa. The phonon-dispersion curves along several high symmetry lines are obtained. The phonon frequencies at the Z point decrease with increasing pressure and completely soften to zero at 27.52?GPa, further confirming the structural instability of NaAlSi.  相似文献   
125.
Trust plays a crucial role in interpersonal relationships, including customer–company relationships, where the customer expects that a company will behave predictably in any particular situation. Companies do not always fulfill customers' expectations and thereby breach the trust relationship. To avoid negative consequences of this trust violation, companies may issue a formal apology as one possible path to regaining customer trust. In the same way, a previous social interaction, which can increase the customer's levels of oxytocin, can help to recover trust after service failures. In this study, three experiments were conducted as follows: the first manipulating a simulated social interaction with images; the second manipulating a physical social interaction, (i.e., a hug); and the third with exogenous oxytocin administration. The results showed that both physical interaction, (i.e., a hug) and simulated social interaction, (i.e., images of people interacting with each other) had a positive effect on customer trust recovery and provided support for oxytocin release as the underlying mechanism in this process. This research contributes to understanding of the link between social interactions and trust by elucidating the effects of both simulated and physical interactions on trust recovery.  相似文献   
126.
127.
Although the relationship between cholesterol and mood states (especially anxiety) has been well studied, few researches have included the role of eating styles in this relationship. This study explored the associations among eating styles, negative emotional symptoms, and levels of cholesterol (and other medical variables) in a population with hypertension and overweight or obesity, analyzing the possible mediation mechanisms involved. A cross-sectional study was conducted in 68 adults with hypertension and overweight/obesity, and stepwise multiple regression analysis and mediation analyses were carried out to test the hypothesis that eating styles mediate the relationship between negative emotional symptoms and cholesterol. Several significant correlations among age, anthropometric, medical, and psychological variables (eating styles and negative emotional symptoms) were found. There was a significant indirect effect of anxiety on total cholesterol and LDL cholesterol through emotional eating. Results suggest that emotional eating has a relevant role in the rise in total and LDL cholesterol, acting as a mediator in the relationship between anxiety and cholesterol. This finding could have important implications, since it introduces a new variable in the relationship between emotions and cholesterol and, therefore, changes the way of understanding this relationship, and of treating high cholesterol in a hypertensive sample.  相似文献   
128.
129.
The current study proposes a new bi-factor rotation method, Schmid-Leiman with iterative target rotation (SLi), based on the iteration of partially specified target matrices and an initial target constructed from a Schmid-Leiman (SL) orthogonalization. SLi was expected to ameliorate some of the limitations of the previously presented SL bi-factor rotations, SL and SL with target rotation (SLt), when the factor structure either includes cross-loadings, near-zero loadings, or both. A Monte Carlo simulation was carried out to test the performance of SLi, SL, SLt, and the two analytic bi-factor rotations, bi-quartimin and bi-geomin. The results revealed that SLi accurately recovered the bi-factor structures across the majority of the conditions, and generally outperformed the other rotation methods. SLi provided the biggest improvements over SL and SLt when the bi-factor structures contained cross-loadings and pure indicators of the general factor. Additionally, SLi was superior to bi-quartimin and bi-geomin, which performed inconsistently across the types of factor structures evaluated. No method produced a good recovery of the bi-factor structures when small samples (N = 200) were combined with low factor loadings (0.30–0.50) in the specific factors. Thus, it is recommended that larger samples of at least 500 observations be obtained.  相似文献   
130.
The effect of retroactive interference between cues predicting the same outcome (RIBC) occurs when the behavioral expression of a cue–outcome association (e.g., A→O1) is reduced due to the later acquisition of an association between a different cue and the same outcome (e.g., B→O1). In the present experimental series, we show that this effect can be modulated by knowledge concerning the structure of these cue–outcome relationships. In Experiments 1A and 1B, a pretraining phase was included to promote the expectation of either a one-to-one (OtO) or a many-to-one (MtO) cue–outcome structure during the subsequent RIBC training phases. We hypothesized that the adoption of an OtO expectation would make participants infer that the previously learned A→O1 relationship would not hold any longer after the exposure to B→O1 trials. Alternatively, the adoption of an MtO expectation would prevent participants from making such an inference. Experiment 1B included an additional condition without pretraining, to assess whether the OtO structure was expected by default. Experiment 2 included control conditions to assess the RIBC effect and induced the expectation of an OtO or MtO structure without the addition of a pretraining phase. Overall, the results suggest that participants effectively induced structural expectations regarding the cue–outcome contingencies. In turn, these expectations may have potentiated (OtO expectation) or alleviated (MtO expectation) the RIBC effect, depending on how well these expectations could accommodate the target A→O1 test association. This pattern of results poses difficulties for current explanations of the RIBC effect, since these explanations do not consider the incidence of cue–outcome structural expectations.  相似文献   
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