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Why IBX Shouldn’t Connect to LaGuardia

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Benjamin Schneider has an interestingly wrong proposal for how to extend the Interborough Express, currently designed to run between Southern Brooklyn and Jackson Heights, toward LaGuardia Airport. I know he cares a lot about urbanist issues and public transportation, so I’d like to explain what’s in this proposal, how it errs, and how it is similar to other problematic proposals, for example by the Regional Plan Association in the Third and Fourth Regional Plans in how it tries to make one centerpiece do too many things. We considered a similar plan for inclusion in A Better Billion and chose not to, and instead connect to the airport via the Manhattan-facing Astoria Line carrying the N and W trains.

What’s the proposal?

The idea is to extend IBX to the airport, in the following way:

The plan adds an infill station for a transfer to the LIRR and extends the line in a slightly roundabout way to connect to an infill Northeast Corridor station before veering to the airport. This distinguishes it from early ideas that didn’t make it to A Better Billion, namely a Y from IBX to both the airport and Harlem. The point of this is not just to connect IBX with the airport but also create a hub by connecting IBX to more things, in this case a transfer station designed to connect people from the entirety of the New Haven Line to LaGuardia.

Why doesn’t this work?

The general answer is that subway lines should be radial or circumferential and not mixed, and this is a mix – IBX is circumferential, connecting stations at a fairly consistent distance from Manhattan, and the extension to the Northeast Corridor (or even Harlem, well north of Midtown) would maintain this character, but a tail veering to the airport would suddenly be radial. Such lines always underperform, because they fail at both the function of a radial line, namely connecting outlying areas to city center, and those of a circumferential, namely connecting lines to one another better and providing near-center neighborhoods with additional service orthogonal to the radial direction.

The more specific answer is that we know where passenger demand to LaGuardia is, and it’s nowhere on IBX or for that matter on the New Haven Line. Airport passenger demand is extremely Manhattan-centric, and within Manhattan it centers on Midtown and the Upper East Side:

At the proposed IBX-NEC transfer point, just about every passenger from the airport would transfer to the commuter trains. The required infrastructure to build this might as well be used on a commuter rail branch, going to East Side Access as it is more central for air travelers than Penn Station based on the above map. IBX is more or less useless. Or, better yet, the Astoria Line can be extended as we propose, along an easier alignment that can be done largely above ground.

Now, what about airport workers? Those are usually mentioned, almost always as an afterthought, in various justifications for lines; I heard transit advocates use that line to argue for Andrew Cuomo’s backward air train idea back when he was still governor. Those are still poorly served by an IBX extension. On a map of airport employee residential density, it looks almost good:

The highest-density zip code on the map above is 11372, whose southwest corner is Jackson Heights. But what’s unclear from the picture above is just how circuitous a swing from Jackson Heights to almost Astoria to LaGuardia is. The straight line distance from Jackson Heights to the nearest potential transfer station location to Terminal B is almost twice that of the direct straight line distance from Jackson Heights to Terminal B. The street grid isn’t straight but neither would an IBX extension be, needing to keep going northwest before turning 120 degrees to the east to get to the terminals. For most people in these neighborhoods, IBX would not provide a trip time improvement over buses.

But more conceptually than this, rail improvements aiming to serve airport workers are generally a bad idea, because airport workers never cluster in one residential place on which a line can be built. The paired density maps are at different scales, and the ratio between the densest and least dense colors is much higher for the air traveler density map than for the airport employee one. OnTheMap gives, as of 2023, 11,000-12,000 airport workers, depending on whether one counts hotel workers across the Grand Central Parkway from the airport in the total. Out of 11,666 on a more generous count, only 3,200 even live in Queens and only 1,182 live in Brooklyn. The blob of seven high-density zip codes of worker origin plus the medium-density one between them (11377, just west of Jackson Heights) only furnishes 1,000 airport workers from all eight zip codes combined.

How does this relate to previous proposals?

There’s a tendency in New York planning, at all levels of officialness from the RPA down, to take one big project that’s politically agreed on and hang everything on it. The Third Regional Plan tried to tie in everything to Second Avenue Subway, to the point of bloating it to a four-track line (by the 1990s all planning was for a two-track line). Even commuter rail, in this case a LIRR Atlantic Branch connection to Lower Manhattan, was shoehorned into it, with through-service onto the subway. The Fourth Plan did the same with its Triboro proposal running through to Metro-North in the Bronx and with commuter rail through-tunnels trying to work around Gateway.

The result of such schemes is proposals that try to have a single line do work it cannot possibly do and would be compromised to the point of unusability if it were forced. In Los Angeles, for example, this is leading to a squiggle of a subway extension of the K (Crenshaw light rail) Line through West Hollywood, 6 km longer than it needs to be. In New York, this is leading to taking IBX, as pure a circumferential as one can be, and lading it with tunnels to destinations for which it doesn’t make sense.

It’s important to resist this temptation. If rail service to LaGuardia is desired, it should use the subway line that already points in that direction, whose alignment allows for an elevated extension, just marginal enough to the residential parts of Astoria to avoid NIMBYs, just close enough to still serve the neighborhood well. The overall planning complexity of two good lines is less than that of one bad line – the cost doesn’t magically increase just because the rail link from Astoria to LaGuardia is categorized as “N/W extension” rather than “IBX extension,” and it’s easier to supervise more, smaller projects if they’re parallelizable.



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satadru
16 hours ago
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Hear! Hear!
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Exposing a Radiation-Hardened 2.4 GHz Wi-Fi Receiver to 500 Kilograys

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Exposing the Wi-Fi chip to gamma radiation. (Credit: Yasuto Narukiyo et al, 2026)
Exposing the Wi-Fi chip to gamma radiation. (Credit: Yasuto Narukiyo et al, 2026)

From outer space to down here on Earth, there are many places where ionizing radiation levels are high enough that they effectively bar access for humans, but also make life miserable for anything containing semiconductor technology. This is especially true for anything involving wireless communications, such as Wi-Fi. However, recently Japanese researchers have created a Wi-Fi chip that is claimed to be so radiation-hardened that it can be used even in gamma ray-rich environments, such as in the worst contaminated depths of the Fukushima Daiichi nuclear reactor.

The indicated dose exposure of 500 kilograys that the chip survived during testing is quite significant. A single gray (Gy) is the absorption of one joule of energy per kilogram of matter. In radiation therapy, a solid epithelial tumor can receive as much as 60 to 80 Gy in a single dose, for example.

That this Wi-Fi chip was still able to function after such a large cumulative dose was therefore quite impressive, as it rivals what space-based probes receive over numerous years. Unfortunately, the research paper is paywalled, but the PR article from the Tokyo Institute of Science fills in a few more details along with the IEEE Spectrum article.

The key was reducing the number of transistors to offer as few targets for radiation as possible. Further inductors were used instead of transistors, for example, variable-gain, as these are less sensitive to ionizing radiation. Remaining transistors were physically enlarged, reducing the number of parallel segments and using NMOS transistors instead of PMOS, due to the latter’s higher radiation resistance.

Although degradation in receiver performance was observed after successive blasts at 300 kGy and then 500 kGy, the change was on the order of 1.5-1.6 dB. The next challenge is to make a Wi-Fi transmitter, which is much harder and may require the addition of materials like diamond.

Designing for a hostile radiation environment is an art form unto itself. And if you are generating radiation, you have to be extra careful.

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satadru
1 day ago
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Nice. Worth noting that there are recent kernel commits for regular mediatek wifi hardware that note adjustments for radiation exposure. POTS hardware is also expected to continue working in radiation exposure environments like space and handle bit flips from radiation exposure!
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Israel's Knesset Expands Jurisdiction of Rabbinic and Sharia Courts

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Israel's Knesset yesterday, by a vote of 65-41, gave final passage to a bill that expands the jurisdiction of the government's Rabbinic and Sharia court systems. According to Times of Israel:

The law, sponsored by the ultra-Orthodox United Torah Judaism and Shas parties, gives the religious tribunals the power to arbitrate civil disputes which are currently the purview of the secular court system. Rabbinical courts were allowed to act as arbitrators in financial disputes until 2006, when a court decision determined that they had no standing to do so....

The law, which initially was set to allow the courts to rule on child custody issues, was amended during the legislative process so that it does not apply to married or formerly married couples. It also does not apply to labor law cases unless the matter was freely initiated by an employee rather than an employer.

The legislation stipulates that religious courts are only allowed to rule on such issues with the consent of both parties and that the rulings reached through rabbinic arbitration cannot violate the Women’s Equal Rights Law or other civil rights statues.

However, critics have asserted that such protections are not enough, given the pressures litigants in religiously conservative communities are likely to face, and that the law will create a power imbalance that’s harmful to weaker segments of society, with women’s rights likely to be affected.

According to the Jerusalem Post, criminal or administrative matters, as well as proceedings in which the state or a local authority was a party are also excluded.

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satadru
3 days ago
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Quote and share highlighted text from any story

1 Comment and 2 Shares

When you share a story on NewsBlur, sometimes the whole article isn’t the point. You want to call out a specific paragraph, a key finding, a sentence that made you think. Until now, you’d have to manually copy-paste text into the comment box and add your own formatting. Now you can select any text in a story, click Quote, and it drops into the share dialog as a styled blockquote, ready for you to add your own commentary underneath.

How it works

Select text in any story and a popover appears with the usual options: Highlight, Train, and Search. There’s now a new option: Quote. Click it, and the share dialog opens with your selected text rendered as a blockquote above the comment field.

Add your own comment below the quote, or just share the quote by itself. The share button updates to say “Share with comment” when there’s a quote or comment present. If you change your mind, click the × on the blockquote to remove it.

Once shared, the blockquote renders with a left border and italic styling in the comment thread, so other readers can see exactly what caught your eye before reading your take on it.

The quote feature works anywhere text selection is available: the story detail view, highlighted text, and search results. It’s available now on the web. If you have feedback or ideas, please share them on the NewsBlur forum.

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satadru
3 days ago
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mareino
1 day ago
I appreciate the added realism of the user comment containing a typo
samuel
1 day ago
hah, an llm wouldn't write that!
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Improving Soda by Turning It Into Mead

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Test tasting soda mead. (Credit: Golden Hive Mead, YouTube)
Test tasting soda mead. (Credit: Golden Hive Mead, YouTube)

You can certainly just chug down that bottle of soda you purchased, but if you accept the premise that the preparation of food and drink is just a subset of chemistry, and that chemistry is fun, then it naturally follows that using soda as the basis for brewing up some mead makes perfect sense. Thus the [Golden Hive Mead] blokes over on YouTube decided to create some Coca Cola flavored mead.

Mead is essentially just water mixed with honey that is left to ferment after adding yeast, resulting in what is also called ‘honey wine’, with an ethanol content of usually between 3.5% and 20%. Since soda is mostly water and comes with its own supply of sugar for yeast to feast on, this isn’t such a crazy choice in that respect. Just make sure to remove the carbonation, as the CO2 makes the soda too acidic for the yeast to be happy.

Instead of straight honey, caramelized honey was used for extra flavor after which the brew was left to ferment for a while. For extra flavor notes aged oak, vanilla and cinnamon were added as well, to ensure that the fermentation didn’t erase those core notes of the coke. The result was apparently rather flavorful, with about a 10.5% ethanol content, receiving the full approval of both tame test tasters.

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HarlandCorbin
4 days ago
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Have a friend who started making mead from Mountain Dew back around '94. I have made mead from rootbeer. This is really nothing new!
satadru
5 days ago
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New York, NY
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Self-healing CMOS Imager to Withstand Jupiter’s Radiation Belt

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Ionizing radiation damage from electrons, protons and gamma rays will over time damage a CMOS circuit, through e.g. degrading the oxide layer and damaging the lattice structure. For a space-based camera that’s inside a probe orbiting a planet like Jupiter it’s thus a bit of a bummer if this will massively shorted useful observation time before the sensor has been fully degraded. A potential workaround here is by using thermal energy to anneal the damaged part of a CMOS imager.

The first step is to detect damaged pixels by performing a read-out while the sensor is not exposed to light. If a pixel still carries significant current it’s marked as damaged and a high current is passed through it to significantly raise its temperature. For the digital logic part of the circuit a similar approach is used, where the detection of logic errors is cause for a high voltage pulse that should also result in annealing of any damage.

During testing the chip was exposed to the same level of radiation to what it would experience during thirty days in orbit around Jupiter, which rendered the sensor basically unusable with a massive increase in leakage current. After four rounds of annealing the image was almost restored to full health, showing that it is a viable approach.

Naturally, this self-healing method is only intended as another line of defense against ionizing radiation, with radiation shielding and radiation-resistant semiconductor technologies serving as the primary defenses.

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satadru
5 days ago
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I've wondered if one could implement self-annealing circuits into structural elements to handle changes due to fatigue.
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