Explaining the Effects of Powerless Language Use on the Evaluative Listening Process: A Theory of Implicit Prototypes

This study examined the effects of forewarning arid discounting messages on the evaluational consequences of powerless language use. The specific forewarning message contained information on types of powerless language (including hesitations) and their effects. The general forewarning message excluded mention of hesitations. The discounting message cautioned against making trait attributions based on powerless language behaviors. In Experiment #1, listeners exposed to the specific and general forewarning messages gave lower competence ratings to the lecturer and were less likely to recommend that he be hired as an instructor. The discounting message did not moderate negative evaluations of the lecturer. In Experiment #2, a one week delay was inserted between the forewarning and discounting messages and the oral presentation. No significant differences were found between the activation conditions and the control condition. The results of this study suggest that the theory of implicit prototypes may explain how the evaluative listening process forms impressions of power· less and powerful sources

The Effects of an Instructor\u27s Use of Hesitation Forms on Student Ratings of Quality, Recommendations to Hire, and Lecture Listening

This study examined the impact of instructor use of hesitation forms ( uh, ah, um, and well ) in an initial encounter with the students on three measures of teaching effectiveness: students ratings of teacher quality, student recommendations to hire, and lecture listening. The instruction of any amount of hesitant speech significantly lowered instructor effectiveness as measured by each dependent variable. Generally, the use of higher frequencies of hesitation forms was more damaging than the use of lower frequencies. The findings of this study suggest that the use of other forms of powerless language may also detract from the teacher effectiveness

Solids maldistribution in parallel cyclones

The amount of solids maldistribution in parallel cyclones was investigated to determine what parameters affected the maldistribution. In many fluidized bed processes with parallel cyclones (as many as 20 in parallel in some cases), it has been noted that unequal erosion (wear) can occur in the cyclones. This results in very short run lengths in order to repair the cyclones with the most wear. This unequal wear has been attributed to unequal solids distribution to the cyclones. In addition to the increased wear, cyclone efficiencies are affected as well. In the specific concern that generated this study, it was found that parallel cyclones in fluidized-bed cokers at Syncrude Canada Ltd. (Syncrude) had unequal amounts of coke buildup on them. This coke buildup on the cyclones causes increased backpressure on the fluidized-bed coker, and after a certain pressure is reached, results in shutdown of the coker. Hot scouring coke, presented at the cyclone inlets, is used to combat the coke formation that is caused by condensation of heavy hydrocarbons. Understanding the scouring coke distribution into the parallel cyclones could lead to reduced deposit maldistribution and increased run length. The testing to determine what causes solids maldistribution in parallel cyclones was conducted using four, 30-cm diameter parallel cyclones that were located above a 0.9-m diameter fluidized bed. Solids flows into the freeboard above the fluidized bed were from the fluidized bed itself and from two pneumatic conveying lines that simulated the lines entering the freeboard of the Syncrude Canada Ltd (Syncrude) fluidized bed coker. The testing was conducted at ambient temperature and pressure using a coke material with a median particle size of 156 microns. The results of the testing showed that although the pressure drop across the cyclones were essentially equal, the gas and solids flow rates through the cyclones could vary significantly. By closing a valve in the dipleg of each of the test cyclones and measuring the rate of buildup of solids in each dipleg, the solids flow rate through each cyclone could be determined. Tests were conducted to vary the gas flow rate through the bed, the amount of solids flow through each pneumatic conveying line and the amount of gas flowing through each cyclone. Depending on conditions, it was found that the ratio of the solids flow rate through the highest-loaded cyclone to the lowest-loaded cyclone could be as much as a factor of four. It was found that the solids distribution in the freeboard above the bed determined the solids flow distribution into each cyclone. Changing the gas flow rate through the cyclone did not affect the solids distribution through the cyclones. It appears that the solids distribute to the cyclones based on the solids distribution at the entrance to the parallel cyclones. The gas flow then distributes itself in order to equalize the pressure drop across the cyclones