Yao B.,IPC |
Yang H.,IPC |
IEEE Control Systems | Year: 2014
The Sixth IFAC Symposium on Mechatronic Systems (MECH 2013) was held on April 10-12, 2013 in Hangzhou, China. The purpose of the symposium is to promote activities in various areas of mechatronics by providing a forum for the exchange of ideas, presentation of technical achievements, and discussion of future directions. An International Program Committee (IPC) of 34 members from 16 countries/regions was responsible for the symposium's technical program. The technical program included a panel forum, Future Education on Mechatronics, and three plenary and four semiplenary lectures representing North America and Asia. The three plenary and four semiplenary lectures were delivered by well-known researchers in the field. The first two semiplenary lectures touched on the various applications of mechatronic systems. Highlights of the symposium included the panel forum session, 'Future Education on Mechatronics,' organized and moderated by IPC Chair Bin Yao.
Levy M.,French National Center for Scientific Research |
Global Biogeochemical Cycles | Year: 2013
The oceanic circulation in the meso to submesoscale regime generates heterogeneity in the concentrations of biogeochemical components over these scales, horizontally between 1 and 100 km. Due to nonlinearities in the biogeochemical reactions, such as phytoplankton primary production and zooplankton grazing, this small-scale heterogeneity can lead to departure from the mean field approximation, whereby plankton reactions are evaluated from mean distributions at coarser scale. Here we explore the magnitude of these eddy reactions and compare their strength to those of the more widely studied eddy transports. We use the term eddy to denote effects arising from scales smaller than ∼ 100 km. This is done using a submesoscale permitting biogeochemical model, representative of the seasonally varying subtropical and subpolar gyres. We found that the eddy reactions associated with primary production and grazing account for ±5-30% of productivity and grazing, respectively, depending on location and time of year, and are scale dependent: two thirds are due to heterogeneities at scales 30-100 km and one third to those at scales below 30 km. Moreover, eddy productivities are systematically negative, implying that production tends to be reduced by nonlinear interactions at the mesoscale and smaller. The opposite result is found for eddy grazing, which is generally positive. The contrasting effects result from vertical advection, which negatively correlates phytoplankton and nutrients and positively correlates phytoplankton and zooplankton in the meso to submesoscale range. Moreover, our results highlight the central role played by eddy reactions for ecological aspects and the distribution of organisms and by eddy transport for biogeochemical aspects and nutrient budgets. ©2013. American Geophysical Union. All Rights Reserved.
News Article | April 18, 2016
South America’s two largest oil producing nations face bigger threats from political turmoil than depressed crude prices, but reforms in their national oil companies (NOC) and energy ministries may be essential for their governments to survive, speakers suggested at an Apr. 12 discussion at the Center for Strategic and International Studies.
News Article | January 5, 2016
Just before the end of 2015, sys admins all over the world woke up to a whimsical message beaming out of their computer screens. “DELETE your logs. Delete your installations. Wipe everything clean, Walk out into the path of cherry blossom trees and let your motherboard feel the stones,” the poem started. It was sent out from an IP address associated with the 32nd Chaos Communication Congress (32c3), an annual arts, politics and security festival that takes place in Hamburg, Germany. The message was fired out to a swathe of the public internet, attempting to hit all the IP addresses it could and leave its musings in administrators’ server logs. The hackers behind the stunt, who called themselves “masspoem4u,” told Motherboard in an encrypted email that the poem potentially reached tens of millions of machines. “One of our goals was to place something beautiful in an unexpected place, nestling a little poetic message amongst repetitive server access logs. We were very happy to hear that many people got a smile out of it!” they said. “Let water run in rivulets down your casing,” the poem continued. “You know that you want something more than this, and I am here to tell you that we love you. We have something more for you. We know you're out there, beeping in the hollow server room, lights blinking, never sleeping.” “We know that you are ready and waiting. Join us.” Masspoem4u—who say they are long time fans of the Congress and attended this year for the first time—used the tool “masscan” to flood the internet with their message. Masscan can be used to scan the entire internet, typically for hunting out vulnerable systems. Robert Graham, one of the tool's creators, demonstrated it at the hacking conference Defcon back in 2014. Graham suggested putting a friendly message along with your scan, so people don't immediately think it's a malicious attack. This is where Masspoem4u pasted their few lines of verse. “We attempted connections to the entire public IPv4 space (excluding private/reserved ranges and other blocks excluded in the default masscan exclude list), meaning that we reached out to almost 4 billion servers (though many of these packets may have been filtered by a firewall before reaching their intended destination),” Masspoem4u said. The actual number of systems reached would be lower. “There appear to be approximately 55 million servers open to connections on port 80 (the standard port for HTTP),” the group continued—these servers could have recognised the communication being sent. Of those, around 30 million returned “non-empty responses” and therefore “would be likely to have logged our poem.” HTTP does have some limitations though. “If we could have covered our message in cute animal stickers, we probably would have, but sadly the HTTP standard does not support this feature,” they wrote. Naturally, this huge, scatter-shot approach takes up a whole lot of bandwidth. Fortunately, the Congress provided attendees with some serious connection speed. “We are also indebted to the 32c3 NOC [network operations centre] team, for providing such great connectivity and encouraging playful experimentation,” Masspoem4u said. “Our poem delivery wasn't pre-planned, but many of the themes behind it are ones we've thought a lot about, and while wandering around 32c3 we saw an opportunity to realize past daydreams with the fast network uplink,” the group continued. Instead of seeing the messages as simply server logs, Masspoem4u envisions “tiny postcards flying across the net, without using any sort of centralized service like Twitter or Facebook (or Weibo, etc.) through which most communications seem to flow these days.” “In this vein, we would like to remind people of the importance of keeping the internet free and decentralized,” the hackers continued. “The internet is ours, and it is adorable.”
News Article | January 5, 2016
The Earth's heat loss from the planet's crust baffled scientists for decades, until now. Scientists discovered a new class of hydrothermal vent system that could precisely explain previous global climate. A hydrothermal vent is an opening in the seafloor out of which flows mineral-rich water that has been heated by magma. The new seafloor vent system could clear up the long-standing debate between actual observations that the Earth's crust is losing heat and the Earth's theoretical cooling rate. The discovery was made by researchers from the University of Southampton and the National Oceanography Centre (NOC) in the United Kingdom. The research team used a combination of remotely operated vehicles and robot-subs to observe the vent system on the seafloor. "Theory has long predicted that there must be more cooling in certain locations on the Earth's crust than we could account for using the known mechanisms and this new class of hydrothermal vent system may account for that difference," said NOC geologist Bramley Murton, who supervised the research. Other hydrothermal vent systems use volcanic heat from magma chambers. The newly discovered hydrothermal vent system type makes use of hot rocks being pushed upward and toward the seabed by tectonic spreading centers, which are low-angle faults. The research team believes that the new hydrothermal vent system type can be found across the globe in various tectonic seafloor spreading locations. The new vent systems will shed new light on the Earth's cooling mechanism, added Murton. The new hydrothermal vent system type was discovered during a Caribbean expedition at the Von Damm Vent Field. The driving process of the new vents is not completely understood, rendering them unaccounted for in existing scientific models that explain how chemistry and heat travel upward from the Earth's crust. The new vents are also nearly invisible to the conventional techniques utilized in searching for hydrothermal vents. The research was published in the journal Nature Communications on Dec. 22, 2015. To measure the vent field, the team used sonar on an autonomous underwater vehicle, the Autosub6000, which then mapped the vent field. The team then sent a remotely operated vehicle (ROV) to the vents to collect mineral samples and hydrothermal fluids. The ROV's multi-beam sonar was also utilized to produce a high-resolution map. An analysis of the samples proved both chemistry and minerals were different form the ones taken from other hydrothermal vents. The chimneys and mounds found in other vents are mostly made up of copper sulfides and iron, while on the Von Damm Vent Field, the 50-meter-tall (almost 165 feet) chimneys and mounds are largely made up of talc, a mineral rich in magnesium. “This research also means that ocean models of magnesium and calcium budgets will need to be updated and could lead to more accurate insights into the Earth’s past climate,” the researchers concluded.