News Article | February 19, 2016
More often than not, real life serves as the inspiration for many great works of fiction. Sometimes, however, a work of fiction allows people to dream bigger and turn a dream into reality. The existence of the F-117 Nighthawk with its "Star Trek"-inspired cloaking device is proof of this. "If you can imagine it, you can create it," writer William Arthur Ward said, and science made sure to deliver on Gene Roddenberry's imagined Klingon cloaking device as best as it could. "It has the front lens from an electro-optically guided glide bomb on the nose with a red light that had a soft pulsing glow showing through a ground glass lens. It had numerous blade antennas from the UHF and VHF frequency spectrum and several faux blowout ports similar to those used as exhaust ports for gas grain generators on early generation nuclear weapons," Retired Air Force Col. Doug Robinson described the device. Of course, all this happened during the Cold War and we know that stealth technology has yet to be perfected until now. To put it simply, the actual Klingon cloaking device was an elaborate ruse but what made it effective and believable was how the select few who were part of the program handled it. "I tell people now that it was only the shape that made that aircraft different, it had all the usual systems, wires and coax," Avionics Technician Brad Smith shared. Smith served in the operations when it was at its most secretive. The most effective cloaking device under the F-117 Nighthawk operations was the willpower of its operatives to keep any and everything they do a secret. This includes keeping operations classified from top government officials - only those who must absolutely know will be given information. "We worked long hours, away from our family for a week at a time," Smith recounted. "Families had no idea where we were, but accepted not knowing as part of their spouse's job. When we came home, families knew not to ask what we did all week." The F-117 Nighthawk only flew at night and all pilots who were involved in the missions practically led a "vampiric life" since they were constantly on night shift. However, despite the stress of the working hours and the utmost secrecy involved in all the operations involving the stealth program, Smith was proud for being able to contribute. The F-117 Nighthawk was retired in 2008 in Type 1000 storage but people still report seeing it in the sky. There is, however, no need to worry about peacekeeping conditions in the United States because Type 1000 storage means an aircraft should still be kept in top shape in case it is needed for active operations. There's no conflict, just the usual maintenance - or is there?
Cortical columnar-level fMRI has already contributed and will further contribute to a deeper understanding of how the brain and mind work by zooming into the fine-grained functional organisation within specialised brain areas. By focussing on this, the project has stimulated a new research line of 'mesoscopic' brain imaging that is gaining increasing momentum in the field of human cognitive and computational neuroscience. This new field complements conventional macroscopic brain imaging that measures activity in brain areas and large-scale networks. Cortical columns are a group of neurons in the brain that run from the top to the bottom of cortex and respond to the same stimulus property. For example, primary visual cortex columns extract small bars with a specific orientation, which are elementary features for analysing the shape of objects. A single cortical column contains thousands or even tens of thousands of neurons corresponding to a few tens of micrometers and up to 1-2 millimetres for larger aggregated columnar structures. 'It has been extremely difficult though to reliably measure cortical columns with non-invasive functional brain imaging in humans, but COLUMNARCODECRACKING has made substantial advances in this,' Prof. Dr Goebel explained. 'We've pushed the limits of technology and have developed new paradigms, analysis methods and modelling tools... We've achieved a sub-millimetre range of spatial resolution that allows us to 'see' larger columns but we still need to increase resolution further to capture more fine-grained columnar organisations.' After using 7 Tesla MRI, the project has started to do this with one of the few 9.4 Tesla scanners in the world. One of the most promising applications that could result from the project's research is the creation of novel powerful brain-computer interfaces (BCIs), using ultra-high field (UHF) fMRI measurements. 'On the one hand, this provides a challenging test bed for our newly acquired knowledge about coding principles in brain areas. On the other hand this research could lead to novel applications for some patients, such as those suffering locked-in syndrome, despite the limited availability of UHF scanners,' said Prof. Dr. Goebel. The project has conducted several 7 Tesla fMRI studies to test whether it is possible to create BCIs that exploit information at the level of columnar-level features. 'This is extremely challenging because we do not focus on brain activity from external stimulation but we investigate brain activity patterns as a result of a participant's imagination, i.e. From self-stimulated brain activity,' explained Prof. Dr. Goebel. 'We have asked participants to imagine a field of dots moving in different directions. With 7 Tesla fMRI, we could then indeed decode from the generated brain activity in the visual cortex which direction of motion a subject has imagined without showing any external visual stimulus.' This is exciting as it indicates for the first time that feature-level information (in this example, different directions of imagined motion) can indeed be used to build fMRI-based UHF BCIs. However, Prof. Dr. Goebel acknowledges that some improvements are required in order to increase the decoding accuracy before the system can be tested on actual patients. In one current study, the project team is testing whether it is possible to build high-resolution BCIs at 7 Tesla that allow subjects to write letters of the alphabet simply by imagining how the letters look. This is challenging as it requires disentangling brain activity that largely overlaps in the same early visual brain areas. The first results with four different letters are promising but it is not yet clear whether this direct letter imagery BCI will reach high accuracies when using all letters of the alphabet. Whilst the project has produced exciting results, Prof. Dr. Goebel emphasises that there is still much research to be undertaken. Whilst the project has mapped the columnar organisation in a few specialised brain areas, there are at least 30 mid-level visual, auditory, somatosensory and multisensory areas where the detailed columnar-level feature representations remain unknown. One example of this is the currently unknown features used by the visual word form area, a region that is active during reading. 'I hope that my current and future research will lead to a deeper understanding of how visual perception and cognition emerge from feature representations and their interactions in the brain,' Prof. Dr. Goebel stated. Such a deeper understanding could indeed pave the way for highly advanced BCIs that could not only help treat neurological disorders but also significantly upgrade humankind's ability to integrate and connect organically with high-powered computer systems. More information: cordis.europa.eu/project/rcn/98761_en.htmlFor more information please see the COLUMNARCODECRACKING CORDIS page:
"Opportunity is driving east and southeast down Marathon Valley, bisecting the region in which we detect smectites [clay minerals] using CRISM [spectrometer] data," Opportunity Deputy Principal Investigator Ray Arvidson, of Washington University in St. Louis, told Universe Today. The ancient, weathered slopes around Marathon Valley became a top priority science destination after they were found to hold a motherlode of 'smectite' clay minerals, based on data obtained from specially targeted and extensive Mars orbital measurements gathered by the CRISM (Compact Reconnaissance Imaging Spectrometer for Mars) spectrometer on NASA's Mars Reconnaissance Orbiter (MRO) – accomplished earlier at the direction of Arvidson. The water altered smectites form under wetter, milder conditions than most rocks at the Opportunity site and under environmental conditions more conducive to support Martian microbial life forms, if they ever existed past or present. Opportunity is investigating relationships among clay-bearing and neighboring deposits for clues about the history of flowing liquid water and environmental changes. With winter now fast approaching, the ever resilient rover has shifted the focus of science investigations – 130 months into her planned 3 month expedition! In mid-October she moved from the northern region to the southern side of Marathon Valley, where the life-giving solar arrays can soak up more of the sun's rays from the sunniest spots along the north-facing tilted slopes and thereby generate more power to continue research activities at the tasty outcrops. "Opportunity is about halfway down the [smectite] detection zone and biased toward north facing "lily pads" on the southern side of the valley for end of drive locations – for power reasons," Arvidson explained. During the next few months of Martian fall and winter, the engineering team will intentionally park Opportunity at end of drive locations where her solar panels are advantageously tilted towards the sun. "Winter solstice is coming up in early January 2016," Arvidson told me. "Effectively we have entered the winter plan of staying along the southern margins of the valley to enjoy north facing slopes and associated increased sunlight. This is the plan for the next number of months, image the floor and gathering some limited MI and APXS data while on the 'lily pads'." The shortest-daylight period of this seventh Martian winter for Opportunity will come on 11 January 2016. Marathon Valley measures about 300 yards or meters long and cuts downhill through the west rim of Endeavour crater from west to east the same direction in which Opportunity is driving. Endeavour crater spans some 22 kilometers (14 miles) in diameter. Along the 'lily pad' route, the six wheeled rover is collecting a wealth of science data where no rover has gone before – in the form of Pancam and navcam camera imaging and spectroscopy – to place the regions outcrops of rocks in geologic context. "At end of drives Opportunity is acquiring Pancam color and stereo images to map the valley floor to better understand the stratigraphy, structure, and color patterns," Arvidson said. See our photo mosaics herein illustrating Opportunity's view around and about Marathon Valley and Endeavour Crater, created by the image processing team of Ken Kremer and Marco Di Lorenzo. Opportunity is also snapping mosaics with the microscopic imager (MI) and gathering analysis of elemental abundances of rocks and soils with the Alpha Particle X-ray spectrometer (APXS). However, the rovers engineering handlers back on Earth have to exercise added caution regarding exactly where they send Opportunity on science forays since she is descending into a step walled narrow valley that can occasionally hamper daily communications with NASA's orbiters flying overhead which relay data back and forth. The high walls to the north and west of the valley ridgeline has already caused several communications blackouts for the "low-elevation Ultra-High-Frequency (UHF) relay passes to the west," according to the JPL team controlling the rover. Another issue that the team occasionally has to deal with is bouts of "amnesia" wherein Opportunity undergoes "unplanned computer resets when using the type of onboard memory that retains information when power is off: flash memory." To avoid "amnesia" engineers successfully implemented a strategy whereby they routinely avoided use of the rovers flash memory by working in RAM-only mode (no Flash for storage). This requires all data collected to be transmitted back to Earth on a daily basis, otherwise it would be lost. "This is being done in RAM mode, where the data are lost if not transmitted down before the rover goes to sleep," Arvidson elaborated. Meanwhile engineers are still trouble shooting the flash memory issue. "Might try to mount FLASH again sometime over the next several weeks." Indeed the team has tested various workarounds and has reinstituted use of flash memory mode. But resets are still occurring infrequently so more investigatory work remains. Overall Opportunity remains healthy with sufficient power to continue operations. The solar arrays produced 344 watt-hours of energy as of Nov. 3, 2015. As of today, Sol 4192, Nov. 9, 2015 Opportunity has taken over 206,560 images and traversed over 26.48 miles (42.62 kilometers). Meanwhile Opportunity's younger sister rover Curiosity traverses and drills into the basal layers at the base of Mount Sharp. And NASA's newest orbiter MAVEN just confirmed that the solar wind stripped away Mars ancient atmosphere in the absence of a global magnetic field causing the evaporative loss of lakes of surface flowing water.
News Article | January 10, 2016
The Moon exerts a tidal force on Earth, but it also holds a similar sway over the human imagination. Few objects have inspired as much speculation and worship than our beaming silver satellite, and the drive to reach it is a cornerstone of civilizations spanning continents and millennia. But it wasn’t until 70 years ago, on January 10, 1946, that this relentless dream finally came to fruition. At 11:58AM that day, military scientists based at Camp Evans, New Jersey shot UHF radio signals at the Moon, and received a bounceback from the lunar surface 2.5 seconds later. The left pulse shows the transmitted signal, while the right pulse shows the bounced back received signal. Image: Radio News Magazine The experiment, dubbed Project Diana after the Roman goddess of the Moon, marked the first time humans had ever actively probed another celestial body, and some even regard it as the birth of the American space program. It was, at the very least, the fundamental bedrock upon which space communication and radar astronomy was built. Indeed, the name Diana was selected not only for its lunar-friendly connotations, but because lead engineer John H. Dewitt Jr., wanted to play up the virgin angle. “The Greek [sic] mythology books said that she had never been cracked,” DeWitt said, according to the history Earth Sound Earth Signal by Douglas Kahn, alluding to Diana’s virginity in Roman myth. Admittedly, that’s kind of a weird way of fetishizing the lunar surface—does DeWitt mean that the Moon lost its virginity to a bunch of Jersey-based light waves? Best not to think about it. The point was that Project Diana had demonstrated, for the first time, that it was possible to transmit information to objects in space, and to learn about the properties of celestial bodies by bouncing light off of them. This would have obvious applications for subsequent spaceflight missions, particularly the Apollo Moon landings, but from the team’s vantagepoint in 1946, that was on neither their figurative or literal radars. “At the time, the handful of scientists working on the project did not feel it was of great long range importance towards putting a man on the Moon,” according to this US Army history of Camp Evans activities between 1907 and 2007. “The first thought, according to [Project Diana mathematician] Walter S. McAfee, was to see if it was possible to bounce an electronic signal. If that could be done, he concluded it would be useful in propagating sound waves.” “People were not thinking of going to the Moon in those days, according to McAfee.” As a side note, it’s worth mentioning that McAfee was denied credit for his crucial role in in Project Diana at the time, possibly because he was African-American, though histories seem to dance around that assumption—including McAfee’s own account. “Sometime later, somebody connected with publicity at the Army was talking with me and said, 'I looked at all those early [press releases] and I don't find you anywhere,” McAfee said in an interview with the New York Historical Commission. “I said, 'I can tell you why, but I don't care to get into a discussion about it.'” Whatever the reason, his contributions, which included the calculation of the relative motions of Earth and the Moon, weren’t acknowledged until much later. It might be pertinent to also mention that Camp Evans served as the Ku Klux Klan’s New Jersey headquarters less than a decade before McAfee worked there. I’m not drawing conclusions—just sayin’. Regardless, thanks to McAfee and the other specialists involved in Project Diana, humanity was able to take its first tangible step towards exploring the Moon...from the Jersey Shore, of all places. Today, the same techniques have been used to explore distant planets, operate vast constellations of satellites, and estimate the Moon’s distance from Earth to within a millimeter—an incredibly precise measurement considering the two bodies have, on average, about 384,400 kilometers between them. Project Diana was a modest experiment at the time, but in retrospect, it opened up the skies.
News Article | March 21, 2016
The digital divide here in the United States has nothing on India, where a billion-plus residents remain un- or under-served by telecoms. In some large part, this is a feature of the country's growing rift between its relatively small urban upper-crust and rural everyone else. Some 70 percent of the country lives in diffuse villages where electricity itself can be scarce and finding a telephone might involve a day's walk. For ISPs, this does not exactly equal dollar signs. It's a problem whose solution would seem to intertwined with solutions to the country's more general woes as development, and the opportunities it offers, leave vast reaches of India behind. In lieu of some huge altruistic ISP investment, how can we imagine some of the most undeveloped parts of world finding their way to this very internet? Animesh Kumar and colleagues at the Indian Institutue of Technology in Bombay have an idea: recapturing unused television "white space" to be repurposed as a medium for providing "backhaul" links in a rural broadband internet scheme, e.g. those segments bridging between major internet backbones and the small would-be subnets at the internet's edge. Their work is described in a paper posted to the arXiv preprint server. "It appears that rural broadband area is a largely untapped market with great potential," Kumar and co. write. "However, there are significant challenges in providing broadband access in the rural areas, including: (i) small average revenue per user as a fraction of total revenue; (ii) high capital and operation expenditure (including license fees); (iii) affordable backhaul which is exacerbated due to a very large population, (iv) energy cost which is worsened by lack of reliable power supply; and, (v) geographic accessibility issues such as right of way problems." As the authors note, there is currently a major rural internet initiative underway in India called BharatNet. This is a government-funded program to bring fiber backhaul to village Gram Panchayat, which are local offices of self-governance (sort of like a city hall for clusters of villages). This will help but not alleviate the connectivity problem, Kumar explains, as the internet will effectively dead end in these offices. Gaining access to the internet will then mean getting to these nodes. What the study authors imagine is a way of cheaply linking these Gram Panchayat PoPs (internet point of presences) with further Wi-Fi subnets in the satellite villages served by those offices: "We envisage that TV white spaces (in the UHF band) can be utilized to backhaul data from village Wi-Fi clusters to the PoP provided by BharatNet." Key to that envisioning is television white space. This is licensed but unused bandwidth that kind of just sits there. The amount of white space available varies quite a bit country by country, for reasons ranging from reuse schemes to government regulation, but in India it turns out that there is a whole lot for the simple reason that there aren't a whole lot of TV stations. As Kumar and his group explain, the UHF band goes almost entirely unused in India. "It has been shown that in almost all cases at least 12 out of the 15 channels 80 percent are available as TV white space in 100 percent of the areas in India," they write. Kumar and co. continue: "It is envisaged that a broadband access network can be provided by extending Internet coverage from a rural PoP provided by BharatNet (an optical fiber point), by using TV white space in the UHF band. In such a scenario, broadband base stations operating in the UHF band will provide backhaul from villages to the PoP provided by BharatNet. Each village can be served by an unlicensed-band Wi-Fi cluster. This architecture can be used to provide affordable broadband access-network in (rural) India ..." The group's proposal is already operating within a testbed connecting 13 villages and hamlets via a white space-based mesh-network linked to a central PoP. It's illustrated below. Creating something that serves a billion people is another matter, of course. The paper argues that it will take a centralized database of license-exempt bandwidth, to start. The white space-sharing problem here is not between TV providers (primary users) and secondary users, as it might be in the United States, but between different secondary users. Managing these conflicts will take some organization and cooperation.