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Comment Re:Or just make the diesels hybrids (Score 2) 171

And even the best public transport system generally isnt going to start and stop *exactly* where you need it, so there still is going to be *some* walking. Which some people with disabilities or health problems simply can't manage. And to achieve a good public transport system - with frequent stops, densely placed stops, relatively direct routes and affordable prices - is entirely dependent on population density far more than it is on "will". In places with high density, it's a relatively straightforward process to have a good public transport system. In places with moderate to low density, it can be difficult to nearly impossible. And weaknesses in public transport system are a viscious cycle: the less frequent the stops, the further spaced out they are, the longer the transit times, and the more expensive the rides - the fewer people will ride them. The fewer that ride the less frequent you have to have the stops, the further apart they need to be, the less direct the routes, and the less affordable the prices.


Lenovo Patches Serious Vulnerabilities In PC System Update Tool (csoonline.com) 36

itwbennett writes: "For the third time in less than six months security issues have forced Lenovo to update one of the tools preloaded on its PCs," writes Lucian Constantin. Last week, the company released version 5.07.0019 of Lenovo System Update, a tool that helps users keep their computers' drivers and BIOS up to date and which was previously called ThinkVantage System Update. The new version fixes two local privilege escalation vulnerabilities discovered by researchers from security firm IOActive.

Submission + - Privacy Vulnerability Exposes VPN Users' Real IP Addresses (thestack.com)

An anonymous reader writes: A major security flaw which reveals VPN users’ real IP addresses has been discovered by Perfect Privacy (PP). The researchers suggest that the problem affects all VPN protocols, including IPSec, PPTP and OpenVPN. The technique involves a port-forwarding tactic whereby a hacker using the same VPN as its victim can forward traffic through a certain port, which exposes the unsuspecting user’s IP address. This issue persists even if the victim has disabled port forwarding. PP discovered that five out of nine prominent VPN providers that offer port forwarding were vulnerable to the attack.
United Kingdom

UK Prisons To Crack Down On Inmate Internet and Mobile Phone Use (thestack.com) 63

An anonymous reader writes: UK prisons will roll out enhanced internet and mobile phone blocking technologies, according to new measures announced yesterday by Chancellor George Osborne in the Autumn Statement. The step, which seeks to stop inmate access to the internet and calls made from mobile devices, will involve part of a £1.3bn investment from the Ministry of Justice to improve the country's Prison Service. Through this strategy, the government hopes to drive "safety improvements" by denying calls and data used on illicit mobile devices. The latest development in blocking technologies promises to be better (paywalled) than earlier systems, which inmates have been able to get around.

London's Deputy Mayor On Ditching Diesel 171

dkatana writes: During an interview in Barcelona last week, at the Smart Cities Congress, London's Deputy Mayor Matthew Pencharz said that he doesn't believe diesel cars belong in cities. He said, "I don't believe that for the urban setting, for light vehicles, diesel is the right thing," He added, "I don't think it is the right thing if you are an urban driver, stopping-starting in traffic all day, not going very far, not zipping along at 50 mph on the motorway. [I think] diesel is not the right technology." He also blamed the European Commission for being too lenient with emission standards and conformity factors. "The conformity factors the Commission [has recently approved] are not as good as we would like, clearly, because we are going to have the same problem again," he said. "The VW scandal has focused attention on a problem we hardly knew about, and it has raised to the top the public policy of failure of dieselization across the European Union, and the UK too, combined with the spectacular failure of the Euro engine standards," he said. "[The scandal] has focused our minds on the fact that we need to accelerate the way out of diesel."

NASA Concludes That Comets, Not Alien Megastructures Orbit KIC 8462852 (examiner.com) 86

MarkWhittington writes: Back in October, findings from the Kepler Space Telescope suggested that something strange was going on around a star called KIC 8462852. Kepler was built to detect exoplanets by measuring the cycles of dimming light from other stars, indicating that a large object was passing between them and Earth. But the dimming light cycle from KIC 8462852 seemed to suggest a lot of smaller objects swarming around it. Scientists narrowed down the explanations to either a swarm of comets or alien megastructures. NASA announced evidence garnered by two other telescopes that pointed to the comet explanation.

Apple Looks To Introduce OLED Displays In iPhone Models From 2018 (thestack.com) 193

An anonymous reader writes: Apple is expected to integrate organic light-emitting diode (OLED) display technology in its iPhone handsets from 2018. The Cupertino-based giant will jump from liquid crystal display (LCD), which has been used in iPhones since 2007, to OLED – turning to suppliers like LG Displays, according to Japanese reports. The switch follows the steps of other smartphone makers such as Samsung and LG, which have both already integrated OLED technology in their mobile device ranges.

Greenwald: Why the CIA Is Smearing Edward Snowden After Paris Attacks (latimes.com) 268

JoeyRox points out that Glenn Greenwald has some harsh words for the CIA in an op-ed piece for the LA Times. From the article: "Decent people see tragedy and barbarism when viewing a terrorism attack. American politicians and intelligence officials see something else: opportunity. Bodies were still lying in the streets of Paris when CIA operatives began exploiting the resulting fear and anger to advance long-standing political agendas. They and their congressional allies instantly attempted to heap blame for the atrocity not on Islamic State but on several preexisting adversaries: Internet encryption, Silicon Valley's privacy policies and Edward Snowden."

Comment Re:Cost of access is key. (Score 1) 329

That was not my point. Ofc we can improve ISP. No idea how much that improves either 'performance' or drops price.

It improves performance a *lot*. As for price, it depends on how expensive that rocket system is. For first stages, an improvement in ISP's effect on the size of the rocket isn't that much greater than linear. But the further up the delta-V chain the engine is used, the more of an impact it has on everything that was used to get it there. An extra hundred sec ISP on a first stage might reduce the system mass by a third; on a second stage up to LEO, maybe cut it in half; on a kick stage for a Mars transfer orbit, maybe cut it by two thirds. On an ascent stage from the surface of Mars... well you get the idea. Shrinking down a rocket to a small fraction of its size - fuel, tankage, and engines - well, that's really significant. ISP is very, very important for upper stages. So you can afford to pay quite a bit for those top stages if it improves their performance. Just not an "unlimited" amount.

There is no way a high tech electrical engine will improve its performance by 10% regardless how much money or time you put into it: the efficiency is already between 98.5% - 99.5%, up to 99.9% in some cases.

This is getting a bit offtopic, but at least the electric engines in EVs don't usually run at nearly that high. Depending on the type they might average 85 to 94% on average. It varies over their load cycle.

Regarding rockets: there is simply not much margin anymore in changing the form of the exhaust tube, burn chamber etc

Actually you can. The general principles of how rocket engines work are fixed, of course - your exhaust will never exceed its local speed of sound in the throat, and then you want to expand it as close to ambient pressure as you want. But the details vary greatly. There's bell nozzles, linear nozzles, annular nozzles, aerospikes, throatless nozzles, atmospheric wake compression, and on and on. There's tons of different ways - developed, in development, and in theory - to pump and inject your propellants - where they need to be pumped at all. Even many propellants that are traditionally thought of as being in one state can be implemented in other states. There's various ways - developed, in development, and in theory - to prevent nozzle erosion. To improve regeneration. To reduce mass. And on and on and on. Rocket combustion is a rather complex thing and we're still trying to get a handle on it. Do you know that we still really don't know how aluminum burns in solid rocket propellant? There's something like five different competing theories. I mean, things like this are a Big Freaking Deal(TM), especially when such small improvements in upper stage ISP have such significance for lower stage mass. And even on your lower stages there's a lot of things that have a big effect on your system cost. For example, how to stop resonant shocks from ripping them up - a lot of people don't realize that one of the main benefits of adding aluminum first stage to propellant mixes is that the droplets of burning aluminum damp shocks. (yeah, it increases ISP too by raising the exhaust temperature, but it also has disadvantages, such as not contributing to expansion, slowing down gases (particularly near the nozzle), and impacting/eroding the throat (or even forming an accumulating slag)

Re, nuclear+chemical. There are proposals for this. The main issue isn't efficiency - the extra chemical energy doesn't make that much of a difference - but thrust. The downside to nuclear thermal is that the reactor is so heavy (fission is like that, unfortunately) that the mass ratio is only something like 3-4:1. That's really bad (you generally get 15-20:1 or even better for a chemical first stage). So the approach is to inject oxygen early in the ascent phase for added thrust, but only run on hydrogen higher up when gravity losses are lower. I'm really not that sanguine about nuclear thermal rockets getting a serious development program any time soon, though. The public overestimates the risk, of course - not only am I sure they'd well seal the fuel elements against whatever damage would be incurred by explosion or reentry, but there's the simple fact that the fuel is "fresh", not contaminated with the more hazardous actinides. But it's going to be a hard sell. And a really hard development project, if they ever did try again. Gigawatt-scale flying nuclear reactors that pose radiation hazards during assembly and test aren't exactly childs' play.

There is very little future in being right when your boss is wrong.