Adaptive indexing is a promising alternative to classical offline index optimization. Under adaptive indexing, index creation and re-organization take place automatically and incrementally as a side-effect of query execution. Adaptive indexing implementations optimize the index’s structure by progressively rewriting it until it converges to a single idealized form such as a sorted array or B-Tr...

Two investigations were carried out to assess the feasibility of using eye movement measures as nonintrusive indicants of,mental workload. In the first experiment, measures of saccadic latency and eye movement velocity were obtained during alternating eye movement scans while subjects were differentially task loaded by simple, moderate, and complex auditory tone counting. The latency and eye mo...

OBJECTIVE The aim of this study was to compare the effectiveness of a new index of perceived mental workload, the Multiple Resource Questionnaire (MRQ), with the standard measure of workload used in the study of vigilance, the NASA Task Load Index (NASA-TLX). BACKGROUND The NASA-TLX has been used extensively to demonstrate that vigilance tasks impose a high level of workload on observers. How...

—This paper proposes a new load balancing strategy, called Comet, for fast multi-agent cluster computing. We use a new load index that takes into account the cost of inter-agent communications. Agents with predictable workload are assigned statically to cluster nodes, whereas agents with unpredictable workload are allowed to migrate dynamically between cluster nodes using a creditbased load bal...

One important aspect of physical database design is the selection of a proper set of indexes for a workload. Creation of indexes in a database system is subject to storage constraints. It is also affected by the ratio of update operations in the workload. Therefore, the cost and benefit of each set of indexes should be evaluated by a proper optimization method. The large number of index sets th...

Endoscopic surgery − a procedure wherein a target organ is displayed on a monitor and physicians use graspers to manipulate the tissue − has benefits for patients in terms of reduced blood loss, infection, and pain. However, physicians’ informal reports indicate that this type of surgery is challenging to perform. These challenges arise from the need to view the target tissue on a monitor, resu...

conclusions the results showed that the heat stress increased by increasing air velocity and humidity in both groups. the air velocity with high humidity can be considered as a positive factor in the occurrence of heat strain. therefore, the incidence of heat stress decreases with the increase of humidity and reduction of air velocity or with increase of air velocity and reduction of humidity i...

Two indices are usually used to estimate air-traffic controllers’ workload: subjective self estimation and objective estimation by counting aircraft to be monitored. However, due to uncertainty and real time pressure, the strain undergone by the controller remains difficult to evaluate objectively. The aim of this paper is to test a new index integrating both, traffic features influencing workl...

Workload in the human brain can be a useful marker of internal brain state. However, due to technical limitations, previous workload studies have been unable to record brain activity via conventional electroencephalography (EEG) and magnetoencephalography (MEG) devices in mobile participants. In this study, we used a wearable EEG system to estimate workload while participants walked in a natura...