BACKGROUND Elevators are ubiquitous and active inside hospitals, potentially facilitating bacterial transmission. The objective of this study was to estimate the prevalence of bacterial colonization on elevator buttons in large urban teaching hospitals. METHODS A total of 120 elevator buttons and 96 toilet surfaces were swabbed over separate intervals at 3 tertiary care hospitals on weekdays ...

We propose a novel approach for group elevator scheduling by formulating it as the maximization of submodular function under a matroid constraint. In particular, we propose to model the total waiting time of passengers using a quadratic Boolean function. The unary and pairwise terms in the function denote the waiting time for single and pairwise allocation of passengers to elevators, respective...

In dentistry, elevator instruments are used to luxate teeth, and this technique imparts forces to tooth particles that sever the periodontal ligament around tooth roots inside the socket and expand alveolar bone around tooth particles. These effects can result in extraction of the tooth particles or facilitate systematic forceps extraction of the tooth particles. This article presents basic ora...

People typically remember objects to which they have frequently been exposed, suggesting that memory is a by-product of perception. However, prior research has shown that people have exceptionally poor memory for the features of some objects (e.g., coins) to which they have been exposed over the course of many years. Here, we examined how people remember the spatial layout of the buttons on a f...

Elevators are the primary method for occupants to move between floors inside modern buildings. Therefore, there have been efforts in minimizing the service delay for a elevator call. Recently, the industry has started to leverage human behavioral patterns in optimizing the elevator dispatching algorithm. However, we argue that it is difficult to judge their gains in the real world, mainly due t...

Heavy vertical traffic conditions appear in high-rise buildings especially during the rush-hour period. So, offered service provided by multi-car elevator systems for such buildings during that period is expected to work fast, efficiently and without long waiting times for users. The approach of our work focuses on reducing the passengers travel and waiting times. To do so Particle Swarm Optimi...

In this paper, an optimal group control for elevator systems is proposed with timed Petri net based approach. Elevator system is modeled by timed Petri nets and hall call response times are estimated with moment generating functions (MGFs) method, which is applicable to real traffic patterns. Two assignment policies are proposed to satisfy the demands of passengers (i.e. hall/car calls) and to ...

Efficient elevator group control is important for the operation of large buildings. Recent developments in this field include the use of fuzzy logic and neural networks. This paper summarizes the development of an evolution strategy (ES) that is capable of optimizing the neuro-controller of an elevator group controller. It extends the results that were based on a simplified elevator group contr...

Monitoring and prediction of passenger movements are able to generate timely heuristic information that reduces the complexity of the elevator dispatching task to one of finding the best route through already computed data. This paper demonstrates that such information, when used by heuristic search techniques, allows optimal dispatching solutions to be achieved in a practical elevator installa...