scholarly journals Drivers’ workload measures to verify functionality of ferry boats boarding area

2020 ◽  
Vol 56 (4) ◽  
pp. 7-17
Author(s):  
Gaetano Bosurgi ◽  
Stellario Marra ◽  
Orazio Pellegrino ◽  
Massimo Villari

Functionality of a square used for ferry boats boarding has repercussions on safety and comfort of users, as well as on the efficiency of maritime transport. Inadequate use of the infrastructure causes driving errors followed by corrective manoeuvres, loss of time and potential accidents with consequences for community and the maritime transport compa-ny. The wide diversification of traffic components and payment methods are generally managed through a traditional horizontal and vertical signage system that does not refer to any current legislation. Therefore, the purpose of this research is to investigate driver's behaviour and the interaction that takes place between the latter and the environ-mental context. In particular, the authors focused on the study of the driver’s workload in a simulated environment, considering a users' sample and different driving scenarios inside the boarding area, concerning traffic conditions (isolated vehicle or presence of disturbing vehicles) and signs position. All this, in order to evaluate whether any change in a virtual context could bring real benefits to drivers, before being transferred to the real context. The results obtained, in terms of subjective workload and performance measures, have made it possible to judge the different solutions proposed in a simulated environment through synthetic indices referring to the entire boarding place or at certain parts of it. In this way, the manager can decide to change the circulation of the entire square or only some aspects of detail, such as some signals, in the event that they manifest an evident difficulty in the transfer of infor-mation. The use of the simulated environment allows greater speed in identifying the best solution, lower costs (avoid-ing the creation of a critical configuration for circulation) and greater user safety, since risky manoeuvres are identi-fied and corrected by the simulator. The proposed procedure can be used by managers for a correct arrangement of the signs, for the purpose of correctly directing the flows and maximizing the flow rate disposed of.

Author(s):  
Joe A. Mascorro ◽  
Gerald S. Kirby

Embedding media based upon an epoxy resin of choice and the acid anhydrides dodecenyl succinic anhydride (DDSA), nadic methyl anhydride (NMA), and catalyzed by the tertiary amine 2,4,6-Tri(dimethylaminomethyl) phenol (DMP-30) are widely used in biological electron microscopy. These media possess a viscosity character that can impair tissue infiltration, particularly if original Epon 812 is utilized as the base resin. Other resins that are considerably less viscous than Epon 812 now are available as replacements. Likewise, nonenyl succinic anhydride (NSA) and dimethylaminoethanol (DMAE) are more fluid than their counterparts DDSA and DMP- 30 commonly used in earlier formulations. This work utilizes novel epoxy and anhydride combinations in order to produce embedding media with desirable flow rate and viscosity parameters that, in turn, would allow the medium to optimally infiltrate tissues. Specifically, embeding media based on EmBed 812 or LX 112 with NSA (in place of DDSA) and DMAE (replacing DMP-30), with NMA remaining constant, are formulated and offered as alternatives for routine biological work.Individual epoxy resins (Table I) or complete embedding media (Tables II-III) were tested for flow rate and viscosity. The novel media were further examined for their ability to infilftrate tissues, polymerize, sectioning and staining character, as well as strength and stability to the electron beam and column vacuum. For physical comparisons, a volume (9 ml) of either resin or media was aspirated into a capillary viscocimeter oriented vertically. The material was then allowed to flow out freely under the influence of gravity and the flow time necessary for the volume to exit was recored (Col B,C; Tables). In addition, the volume flow rate (ml flowing/second; Col D, Tables) was measured. Viscosity (n) could then be determined by using the Hagen-Poiseville relation for laminar flow, n = c.p/Q, where c = a geometric constant from an instrument calibration with water, p = mass density, and Q = volume flow rate. Mass weight and density of the materials were determined as well (Col F,G; Tables). Infiltration schedules utilized were short (1/2 hr 1:1, 3 hrs full resin), intermediate (1/2 hr 1:1, 6 hrs full resin) , or long (1/2 hr 1:1, 6 hrs full resin) in total time. Polymerization schedules ranging from 15 hrs (overnight) through 24, 36, or 48 hrs were tested. Sections demonstrating gold interference colors were collected on unsupported 200- 300 mesh grids and stained sequentially with uranyl acetate and lead citrate.


2018 ◽  
Author(s):  
Nicola Jane Holt ◽  
Leah Furbert ◽  
Emily Sweetingham

The current research sought to replicate and extend work suggesting that coloring can reduce anxiety, asking whether coloring can improve cognitive performance. In two experiments undergraduates (N = 47; N = 52) colored and participated in a control condition. Subjective and performance measures of mood and mindfulness were included: an implicit mood test (Experiment 1) and a selective attention task (Experiment 2) along with a divergent thinking test. In both experiments coloring significantly reduced anxiety and increased mindfulness compared with control and baseline scores. Following coloring participants scored significantly lower on implicit fear, than the control condition, and significantly higher on selective attention and original ideation. Coloring may not only reduce anxiety, but also improve mindful attention and creative cognition.


2004 ◽  
Vol 79 (3) ◽  
pp. 545-570 ◽  
Author(s):  
Margaret A. Abernethy ◽  
Jan Bouwens ◽  
Laurence van Lent

We investigate two determinants of two choices in the control system of divisionalized firms, namely decentralization and use of performance measures. The two determinants are those identified in the literature as important to control system design: (1) information asymmetries between corporate and divisional managers and (2) division interdependencies. We treat decentralization and performance measurement choices as endogenous variables and examine the interrelation among these choices using a simultaneous equation model. Using data from 78 divisions, our results indicate that decentralization is positively related to the level of information asymmetries and negatively to intrafirm interdependencies, while the use of performance measures is affected by the level of interdependencies among divisions within the firm, but not by information asymmetries. We find some evidence that decentralization choice and use of performance measures are complementary.


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