PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

When will your elevator arrive?

Two physicists do the math.

2021-05-03
(Press-News.org) The human world is, increasingly, an urban one -- and that means elevators. Hong Kong, the hometown of physicist Zhijie Feng (Boston University),* adds new elevators at the rate of roughly 1500 every year...making vertical transport an alluring topic for quantitative research.

"Just in the main building of my undergraduate university, Hong Kong University of Science and Technology," Feng reflects, "there are 37 elevators, all numbered so we can use them to indicate the location of hundreds of classrooms. There is always a line outside each elevator lobby, and if they are shut down, we have to hike for 30 minutes."

Feng and Santa Fe Institute Professor Sidney Redner saw this as an opportunity to explore the factors that determine elevator transport capabilities. In their new paper in the Journal of Statistical Mechanics, they begin by making a deliberately simple "toy" model.

"Engineers have already developed computational models for simulating elevators as realistically as possible," says Feng. "Instead, we wanted insight into basic mechanisms, using just enough parameters to describe what we see in a way we can fully understand."

Their minimum-variable simulation makes six key assumptions: unoccupied buildings, first-come-first-served transport, identical elevators traveling to uniformly distributed destination floors, 2.5 seconds to enter or exit elevators, and one second to travel from one floor to the next.

For a 100-story building with one idealized infinite-capacity elevator, Feng and Redner find that waiting times typically fall between five and seven minutes. With elevators that can carry 20 people each, and buildings that hold 100 workers per floor, this cycle requires 500 trips over 2 hours -- or 21 elevators -- to get everyone to work on time.

"If the elevators are uncorrelated," the authors write, wait time "should equal the single elevator cycle time divided by the number of elevators, which is roughly 15 seconds." However, this efficient spacing of elevators doesn't last: as passenger demand increases, elevators start to move in lockstep, creating traffic jams in the lobby below until multiple elevators arrive back on the ground floor at the same time.

These nonlinear dynamics stymie any easy answer to the question of how long a person has to wait. But to Feng and Redner this is just the entry-level to a bigger inquiry. "I hope our work could be a 'pocket version' model to extend from," Feng remarks. She credits Redner's textbook, which she read in her early undergraduate days, for inspiring her love of breaking down complex problems into simple models.

Some of the further questions they identify include, "If a building tapers with height, is there a taper angle that minimizes waiting time but optimizes office space?"; and, "What if some elevators only service certain floors, and others service different floors?"

Food for thought next time you're waiting in the lobby...

INFORMATION:

*Feng is a graduate student in the Physics Department at Boston University. She began her work on elevators in the summer of 2019 during her Complexity Undergraduate Research internship at the Santa Fe Institute.



ELSE PRESS RELEASES FROM THIS DATE:

Towards a treatment for myotonic dystrophy: First 3D model with patient cells

Towards a treatment for myotonic dystrophy: First 3D model with patient cells
2021-05-03
Myotonic dystrophy is a hereditary degenerative neuromuscular disease that occurs mainly in adults, affecting about 50,000 people only in Spain. Symptoms range from difficulty walking and myotonia (great difficulty in relaxing the contracted muscles) to severe neurological problems, leading to progressive disability that unfortunately puts many of those affected in a wheelchair. This disease is very heterogeneous among patients (age of onset, progression, hereditary transmission, affected muscles), which makes the development of generic treatments especially complex. Currently, drugs against myotonic ...

College athletes in supportive programs coping better with pandemic, study shows

2021-05-03
LAWRENCE -- Like much of society, college athletics were thrown into disarray by the COVID-19 pandemic. While student athletes were suddenly prevented from competing, training or seeing as much of their teammates and coaches, those who perceived they were part of a positive sporting environment also coped better during the early days of the crisis, a new study from the University of Kansas has found. KU researchers have long studied a caring, task-involved sporting climate, in which young athletes receive support and recognition for their efforts, while mistakes are treated as learning opportunities. But the pandemic provided a unique opportunity to see whether the approach helped collegiate athletes cope with the unique stresses and challenges that came with the disruption ...

Need to vent? Turn to real-life support, not social media

2021-05-03
Social media may make it easier for people to engage online, but I does not provide certain benefits of real-life human interactions, says a Michigan State University researcher. "Problematic social media use has been associated with depression, anxiety and social isolation, and having a good social support system helps insulate people from negative mental health," said Dar Meshi, an assistant professor in the Department of Advertising and Public Relations at MSU. "We wanted to compare the differences between real-life support and support provided over social media to see if the support provided over social media could have beneficial effects." The research was published online April 29 in the journal Addictive Behaviors. While ...

Will your future clothes be made of algae?

Will your future clothes be made of algae?
2021-05-03
Living materials, which are made by housing biological cells within a non-living matrix, have gained popularity in recent years as scientists recognize that often the most robust materials are those that mimic nature. For the first time, an international team of researchers from the University of Rochester and Delft University of Technology in the Netherlands used 3D printers and a novel bioprinting technique to print algae into living, photosynthetic materials that are tough and resilient. The material has a variety of applications in the energy, medical, and fashion sectors. The research is published in ...

New research shows long-term recovery possible for areas impacted by seagrass die-off

New research shows long-term recovery possible for areas impacted by seagrass die-off
2021-05-03
Nearly 10,000 acres of lush seagrass vanished from Florida Bay between 1987 and 1991, leading to massive ecological changes in the region near the Florida Keys. Abundance of the seagrass, Thalassia testudinum, more commonly known as turtlegrass, a foundation species of the Florida Bay ecosystem, decreased extensively during what is considered to be one of the largest declines in seagrass cover in recent history. Researchers from the University of South Florida, the Florida Fish and Wildlife Conservation Commission (FWC) and the University of North Carolina Wilmington documented the response of seagrasses after the die-off. ...

31% of dogs and 40% of cats tested positive to COVID-19 after owners' diagnoses

2021-05-03
31 percent of pet dogs and 40 percent of pet cats tested positive to COVID-19 after their owners' own diagnoses, though under half displayed symptoms, in small Brazilian study. INFORMATION: Publicly available article: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250853 Article Title: Investigation of SARS-CoV-2 infection in dogs and cats of humans diagnosed with COVID-19 in Rio de Janeiro, Brazil Funding: MMS: This study was supported by CGLab/MoH (General Laboratories Coordination of Brazilian Ministry of Health), CVSLR/FIOCRUZ (Coordination of Health Surveillance and Reference Laboratories ...

The neural mechanism of autonomous learning uncovered by researchers at IBEC

The neural mechanism of autonomous learning uncovered by researchers at IBEC
2021-05-03
Thanks to the so-called deep learning, a subset of artificial intelligence (AI) algorithms inspired by the brain, machines can match human performance in perception and language recognition and even outperform humans in certain tasks. But do these synthetic biologically inspired systems learn in the same way that we do? According to a new article by first author Dr. Diogo Santos-Pata from the Synthetic Perceptive, Emotive and Cognitive Systems lab (SPECS) at IBEC led by ICREA Professor Paul Verschure, in collaboration with Prof. Ivan Soltesz at Stanford University, the mechanism of autonomous learning underlying these AI systems reflects nature more closely than previously thought. With their hypothesis and model, these scientists offer new insights into ...

Limited fishing zones support reef conservation

Limited fishing zones support reef conservation
2021-05-03
A world first study within the Great Barrier Reef Marine Park has found limited fishing zones (yellow zones) are still important conservation and fisheries management tools when paired with no-fishing zones. Lead author Dr April Hall, from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE at JCU), said partially protected yellow zones still contain healthy numbers of reef fish targeted for recreational and commercial fishing. These include coral trout, tropical snappers, emperors and tuskfish. Yellow zones limit, rather than prohibit, fishing through fishing gear restrictions. For example, limited line fishing is allowed with one rod or line and one hook per ...

Nanotechnology offers new hope for bowel cancer patients

Nanotechnology offers new hope for bowel cancer patients
2021-05-03
Bowel cancer survival rates could be improved if chemotherapy drugs were delivered via tiny nanoparticles to the diseased organs rather than oral treatment. That's the finding from Indian and Australian scientists who have undertaken the first study, using nanoparticles to target bowel cancer, the third most common cancer in the world and the second most deadliest. The researchers have shown in animal experiments that nanoparticles containing the chemotherapy drug Capecitabine (CAP) attach themselves directly to the diseased cells, bypassing healthy cells and therefore reducing toxic side effects as well as the size and number of tumours. The scientists, from the Manipal Academy of Higher Education, Indian Institute of Science and the University of South Australia, ...

Natural immunity to malaria provides clues to potential therapies

Natural immunity to malaria provides clues to potential therapies
2021-05-03
National Health and Medical Research Council, the European Research Council and the Victorian Government. WEHI researchers have identified how natural human antibodies can block malaria parasites from entering red blood cells, potentially indicating how new protective therapies could be developed against this globally significant disease. The research provides greater insight into how antibodies block the entry of Plasmodium vivax malaria parasites into young red blood cells called reticulocytes. It builds on an earlier discovery that the P. vivax latches onto the transferrin receptor 1 (TfR1) to enter cells. The research, led by Associate Professor Wai-Hong Tham and PhD student Li-Jin Chan ...

LAST 30 PRESS RELEASES:

Post-LLM era: New horizons for AI with knowledge, collaboration, and co-evolution

“Sloshing” from celestial collisions solves mystery of how galactic clusters stay hot

Children poisoned by the synthetic opioid, fentanyl, has risen in the U.S. – eight years of national data shows

USC researchers observe mice may have a form of first aid

VUMC to develop AI technology for therapeutic antibody discovery

Unlocking the hidden proteome: The role of coding circular RNA in cancer

Advancing lung cancer treatment: Understanding the differences between LUAD and LUSC

Study reveals widening heart disease disparities in the US

The role of ubiquitination in cancer stem cell regulation

New insights into LSD1: a key regulator in disease pathogenesis

Vanderbilt lung transplant establishes new record

Revolutionizing cancer treatment: targeting EZH2 for a new era of precision medicine

Metasurface technology offers a compact way to generate multiphoton entanglement

Effort seeks to increase cancer-gene testing in primary care

Acoustofluidics-based method facilitates intracellular nanoparticle delivery

Sulfur bacteria team up to break down organic substances in the seabed

Stretching spider silk makes it stronger

Earth's orbital rhythms link timing of giant eruptions and climate change

Ammonia build-up kills liver cells but can be prevented using existing drug

New technical guidelines pave the way for widespread adoption of methane-reducing feed additives in dairy and livestock

Eradivir announces Phase 2 human challenge study of EV25 in healthy adults infected with influenza

New study finds that tooth size in Otaria byronia reflects historical shifts in population abundance

nTIDE March 2025 Jobs Report: Employment rate for people with disabilities holds steady at new plateau, despite February dip

Breakthrough cardiac regeneration research offers hope for the treatment of ischemic heart failure

Fluoride in drinking water is associated with impaired childhood cognition

New composite structure boosts polypropylene’s low-temperature toughness

While most Americans strongly support civics education in schools, partisan divide on DEI policies and free speech on college campuses remains

Revolutionizing surface science: Visualization of local dielectric properties of surfaces

LearningEMS: A new framework for electric vehicle energy management

Nearly half of popular tropical plant group related to birds-of-paradise and bananas are threatened with extinction

[Press-News.org] When will your elevator arrive?
Two physicists do the math.