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Justin Mason's Weblog Posts

Links for 2021-12-06

  • An upper bound on one-to-one exposure to infectious human respiratory particles | PNAS

    Masks just work:

    Our results show that face masks significantly reduce the risk of SARS-CoV-2 infection compared to social distancing. We find a very low risk of infection when everyone wears a face mask, even if it doesn’t fit perfectly on the face.

    (tags: masks covid-19 papers face-masks infection)

  • Ikea Vindriktning Air Quality Sensor Review and Accuracy

    ‘Ikea recently came out with a range of air purifiers and also an air quality sensor. The Vindriktning does not have a display but shows the air quality data in the form of a traffic light with red, yellow and green LEDs. One of the most striking features is actually the price as it costs only around EUR 10 depending where you live. It looks very nice and the build quality is quite good but this article will look beyond the looks and see how good it is at actually measuring the air quality.’ The results are mixed: ‘I really want to like the Vindriktning! It has a great built quality and price and is very simple to use. The addition of a small fan to improve the air flow through the sensor is a good upgrade and shows that Ikea wants to provide accurate measurements — even with a cheap sensor. However, the defined cut off values for the air quality and its description as “Good”, “OK”, and “Not Good” are not based on science or international recommendations and create the false understanding that the air is good, when in fact it is not good at all. I do hope that in one of the next upgrades of the Vindriktning, Ikea will bring its traffic light indicators more in line with WHO recommendations on healthy air quality.’ Personally, this sounds useful — as long as one remembers that the “OK” air quality level is in fact well into the “unhealthy” zone. Bit mysterious as to why IKEA made this choice though…

    (tags: ikea air-quality pm2.5 pm10 particulates home devices gadgets)

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Links for 2021-12-03

  • The Labyrinth Stone

    In medieval times the labyrinth underwent a revival and became primarily a symbol of pilgrimage, and in particular pilgrimage to the holy shrine of Jerusalem (Coleman & Elsner 1995, 112). Shortly after the loss of Jerusalem to the Muslims in the twelfth century, large labyrinths of mosaic or paving stones were incorporated into the western nave bays of a number of European cathedrals in the twelfth and thirteenth centuries (Connolly 2005, 286). [….] By walking, or in some cases crawling on their knees, along the labyrinth, pilgrims could perform an imagined pilgrimage to Jerusalem (Westbury 2001, 51-52).

    (tags: pilgrimage history labyrinths mazes via:neil-jackman)

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Links for 2021-11-24

  • FIND

    “Framework for Internal Navigation and Discovery” — track device locations using active or passive (wifi-based) scan methods within a house or office, then trigger Home Assistant automation based on device locations — e.g. turning on or off heating in specific rooms, etc.

    (tags: location home-assistant home automation tracking devices)

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Links for 2021-11-23

  • Google Cloud incident was caused by a race condition which triggered 30 minutes before the bugfix deployment was due to complete

    Wow, this was tragic! “A Google engineer discovered this bug on 12 November, which caused us to declare an internal high-priority incident because of the latent risk to production systems. After analyzing the bug, we froze a part of our configuration system to make the likelihood of the race condition even lower. Since the race condition had existed in the fleet for several months already, the team believed that this extra step made the risk even lower. Thus the team believed the lowest-risk path […] was to roll out fixes in a controlled manner as opposed to a same-day emergency patch. […] Gradual rollouts of both patches started on Monday, 15 November, and patch B completed rollout by that evening. On Tuesday, 16 November, as the patch A rollout was within 30 minutes of completing, the race condition did manifest in an unpatched cluster, and the outage started.”

    (tags: cloud outages tragic google race-conditions gclb patching deployment ops)

  • “Risk compensation” is garbage

    Risk compensation does occur in very narrow and specific circumstances, but all the studies purporting to show that it is a widespread, predictable outcome of any safety regulation have failed to replicate. […] Risk compensation and health-and-safety panic are both part of a safety nihilism campaign that serves big business’s deregulatory agenda, and the cruel moralizing of right wing religious maniacs, the traditional turkeys-voting-for-Christmas coalition. But risk compensation is especially salient in these covid days, where it’s being used to fight rapid testing (“encourages risky behavior”).

    (tags: risk-compensation risks safety)

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Links for 2021-11-09

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Links for 2021-11-08

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Links for 2021-11-02

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Links for 2021-10-26

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Links for 2021-10-22

  • GNI report on biomethane generation in Ireland

    Good news for biogas feasability here: ‘This report seeks to provide scientific analysis and real-world data on the key questions and knowledge gaps concerning the sustainability of an Irish agricultural-led biomethane industry. The core aim of this report is to assess whether Ireland can develop an environmentally sustainable biomethane industry without creating unintended negative consequences. […] This report provides evidence that the development of a sustainable biomethane industry in Ireland is technically feasible and so long as it is developed in a co-ordinated manner, can avoid any negative unintended consequences. As such, a number of proven methodologies have been provided to drive the rollout of a biomethane industry whilst ensuring continued agricultural productivity and improved environmental sustainability.’

    (tags: biogas biomethane methane fuel ireland sustainability climate-change gni farming)

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Links for 2021-10-20

  • Datamuse API

    This is extremely cool! “a word-finding query engine for developers. You can use it in your apps to find words that match a given set of constraints and that are likely in a given context. You can specify a wide variety of constraints on meaning, spelling, sound, and vocabulary in your queries, in any combination. Applications use the API for a wide range of features, including autocomplete on text input fields, search relevancy ranking, assistive writing apps, word games, and more.” (via Rob Manuel)

    (tags: dictionary nlp words writing apis rhymes sounds-like adjectives nouns suggestions)

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Links for 2021-10-18

  • Transmission of SARS-CoV-2 After COVID-19 Screening and Mitigation Measures for Primary School Children Attending School in Liège, Belgium

    This paper from a school in Belgium is really worrying, given Ireland’s approach to schools and COVID-19. “Despite the implementation of several mitigation measures, the incidence of COVID-19 among children attending primary school in this study was comparable to that observed among teachers and parents. Transmission tree reconstruction suggests that most transmission events originated from within the school.”

    Question: What is the possible role of children in SARS-CoV-2 transmission? Findings: This cohort study including 63 children and 118 adults found no significant difference between the number of children and the number of adults testing positive for SARS-CoV-2 infection during the study period; children were asymptomatic significantly more often compared with adults (46% vs 13%). In addition, a reconstruction of the outbreak showed that most transmission events originated from within the school. Meaning: These results suggest that children may play a larger role in the transmission of SARS-CoV-2 than previously assumed.

    (tags: transmission schools education covid-19 sars-cov-2 papers belgium infection)

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Links for 2021-10-17

  • “Grievance Mining”

    What a great term for what the Tories are up to in the UK: “Facing chaos and needing a scapegoat, the Tories seek an endless fight with Europe” —

    Frost is well aware of the futility of his demands – indeed, it is the whole point of his Lisbon performance. Instead of declaring victory, accepting the EU’s munificent offers and turning down the heat in Northern Ireland, he and Johnson prefer to make an impossible demand so that they can blame the EU for rejecting it. They are, as the South Belfast MP, Claire Hanna, has put it, “mining for grievance”.

    (tags: grievances neologisms phrases boris-johnson uk brexit politics northern-ireland eu)

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Links for 2021-10-14

  • Fruit fly brains include a variant of a Bloom filter data structure

    Wow, this is incredible!

    We found that the fruit fly olfactory circuit evolved a variant of a Bloom filter to assess the novelty of odors. Compared with a traditional Bloom filter, the fly adjusts novelty responses based on two additional features: the similarity of an odor to previously experienced odors and the time elapsed since the odor was last experienced. We elaborate and validate a framework to predict novelty responses of fruit flies to given pairs of odors. We also translate insights from the fly circuit to develop a class of distance- and time-sensitive Bloom filters that outperform prior filters when evaluated on several biological and computational datasets. Overall, our work illuminates the algorithmic basis of an important neurobiological problem and offers strategies for novelty detection in computational systems.

    (tags: fruit-flies data-structures algorithms brains neuroscience smell)

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Links for 2021-10-08

  • Let’s Encrypt Root Expiration – Post-Mortem

    Overall, I think the expiration of the Let’s Encrypt CA certificates went really quite well, largely due to the work Let’s Encrypt did around arranging for a new cross-signed chain to be available beyond the expiration of the IdenTrust root. That said, there were far more issues in areas we didn’t anticipate. Modern devices, all the way through to latest versions of iOS and macOS hit issues when connecting to servers that had a misconfigured certificate chain and quite serious issues from huge companies like Google and Microsoft in their cloud products that could no longer validate certificate chains was surprising to say the least. In all, I think this just highlights something that many of us that work in this space have known for some time, that TLS/PKI are complex and fragile systems that often go overlooked for long periods of time because they ‘just work’ most of the time. [….] One thing that’s certain is that this event is coming again. Over the next few years we’re going to see a wide selection of Root Certificates expiring for all of the major CAs and we’re likely to keep experiencing the exact same issues unless something changes in the wider ecosystem.

    (tags: postmortem ssl tls pki fail post-mortems lets-encrypt cas)

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Links for 2021-10-06

  • Frances Haugen says Facebook’s algorithms are dangerous. Here’s why. | MIT Technology Review

    This is a good article on FB’s disastrous situation, which would be bad enough were it not endangering our societies. Despite warnings from Google and others, they switched their engagement optimization tactics to rely heavily on machine learning, which (as noted elsewhere) devolves into a situation where it’s thoroughly inscrutable:

    It developed an internal tool known as FBLearner Flow that made it easy for engineers without machine learning experience to develop whatever models they needed at their disposal. By one data point, it was already in use by more than a quarter of Facebook’s engineering team in 2016. Many of the current and former Facebook employees I’ve spoken to say that this is part of why Facebook can’t seem to get a handle on what it serves up to users in the news feed. Different teams can have competing objectives, and the system has grown so complex and unwieldy that no one can keep track anymore of all of its different components. […] “64% of all extremist group joins are due to our recommendation tools,” the presentation said, predominantly thanks to the models behind the “Groups You Should Join” and “Discover” features. […] These phenomena are far worse in regions that don’t speak English because of Facebook’s uneven coverage of different languages. […] When the war in Tigray[, Ethiopia] first broke out in November, [AI ethics researcher Timnit] Gebru saw the platform flounder to get a handle on the flurry of misinformation. […] When fake news, hate speech, and even death threats aren’t moderated out, they are then scraped as training data to build the next generation of [language models]. And those models, parroting back what they’re trained on, end up regurgitating these toxic linguistic patterns on the internet.”
    What. A. Mess.

    (tags: machine-learning social-networking facebook the-algorithm llms models frances-haughen)

  • The Verica Open Incident Database (VOID)

    ‘A community-contributed collection of software-related incident reports’ — this looks like it’ll be a great resource.

    (tags: resilience engineering ops outages post-mortems rcas five-whys incidents)

  • debunking “it takes 48,000 miles for an EV to be greener than an ICE vehicle”

    Looks like this is disinformation produced by an Aston-Martin-affiliated lobbyist/PR company — the true figure is 18,000 miles

    (tags: debunking pr lobbying cars evs aston-martin spin greenwashing)

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Links for 2021-10-05

  • _Endgame: A zero-carbon electricity plan for Ireland_

    A report commissioned by Wind Energy Ireland in June 2021 — key findings:

    Reducing power sector CO2 emissions in Ireland from around 9 million tonnes today to a target of less than 2 million tonnes of CO2 per year is very achievable by 2030, using the approach currently underway to achieve the ‘70 by 30’ target, and implementing more of existing and proven technologies; The current Programme for Government renewable capacity targets of 8.2 GW of onshore wind and 5 GW of offshore wind by 2030 should be maintained, with an additional target of 5 GW of solar PV. This target can be achieved at a lower cost to the end consumer in Ireland, compared to delivery of the less ambitious ‘70 by 30’ target. A zero-carbon power system is possible by 2030 and represents an achievable target in the 2030s.

    (tags: wind-energy energy ireland future 2030 climate-change co2 solar-power carbon)

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Links for 2021-10-04

  • Wanghong

    At the simplest level, [wanghong] means “internet famous,” referring in its earliest iterations to viral personalities or social media influencers. The word has since mutated, expanding and venn-diagramming with a particular hipster aesthetic, strands of urban design and kinds of tech platform architecture.

    (tags: celebrity china photography internet neologisms wanghong instagram fame viral internet-famous)

  • The Three DynamoDB Limits You Need to Know

    tl;dr: the item size limit, the pagination page size limit for query and scans; and the partition throughput limits (which bit me earlier this year).

    (tags: dynamodb limits aws coding ops)

  • Orthodoxy, illusio, and playing the scientific game: a Bourdieusian analysis of infection control science in the COVID-19 pandemic

    I remember seeing discussion of aerosol and airborne transmission of SARS-CoV-2 observed in Asia, right back at the start of 2020. This paper is right; the WHO in particular were careful to write this off as incorrect, and tell people that it was transmitted mainly via droplets, which we now know was a massive failure.

    Scientific and policy bodies’ failure to acknowledge and act on the evidence base for airborne transmission of SARS-CoV-2 in a timely way is both a mystery and a scandal. In this study, we applied theories from Bourdieu to address the question, “How was a partial and partisan scientific account of SARS-CoV-2 transmission constructed and maintained, leading to widespread imposition of infection control policies which de-emphasised airborne transmission?”. […] Results: Political and policy actors at international, national, and regional level aligned — predominantly though not invariably — with medical scientific orthodoxy which promoted the droplet theory of transmission and considered aerosol transmission unproven or of doubtful relevance. This dominant scientific sub-field centred around the clinical discipline of infectious disease control, in which leading actors were hospital clinicians aligned with the evidence-based medicine movement. Aerosol scientists — typically, chemists, and engineers — representing the heterodoxy were systematically excluded from key decision-making networks and committees. Dominant discourses defined these scientists’ ideas and methodologies as weak, their empirical findings as untrustworthy or insignificant, and their contributions to debate as unhelpful.

    (tags: via:naomi-wu covid-19 discourse infection bourdieu transmission aerosols droplets)

  • Microsoft’s million-tonne CO2-removal purchase — lessons for net zero

    Via David Roberts: “Microsoft is trying to go carbon-negative. Its recent RFP solicited bids for 154 million tonnes of negative emissions; of those, only *2 million tonnes* met its criteria for real, permanent CO2 removal. It has written up its challenges in Nature.” “We write as a team composed of Microsoft staff working on the company’s carbon-negative programme, and research scientists who analyse carbon reduction and removal strategies. We highlight three ‘bugs’ in the current system: inconsistent definitions of net zero, poor measurement and accounting of carbon, and an immature market in CO2 removal and offsets. These challenges need to be overcome if the world is to reach net zero by mid-century.”

    (tags: earth co2 microsoft stripe carbon carbon-capture climate-change net-zero)

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Links for 2021-10-03

  • Forrest Fleischman on “trillion trees” projects

    Some good points:

    A project whose goal is to plant a certain number of trees is particularly vulnerable to failure because its counting the wrong thing. If the goal is to absorb emissions, we should count the carbon, not the trees. A few small large absorb more carbon than a bunch of little trees. When we plant trees with carbon uptake or forest restoration as a goal, we don’t try to maximize the number of trees. We try to maximize long-term carbon uptake, and this might actually mean planting fewer trees up front.

    (tags: forestry science data climate-change planting trees forests carbon-capture carbon)

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Links for 2021-09-30

  • Introducing Echo Show 15

    Amazon’s new “Full HD 15.6″ smart display for family organisation with Alexa”. I’ve built something similar (though much more basic) for our home using an e-Paper display and a Raspberry Pi, so I’m interested. My take: it looks very busy, heavy on the Alexa lock-in, would omit lots of useful data sources (like Home Assistant), and of course the spyware factor is a biggie — although on that note it’s interesting that there’s a prominent “mic/camera off” switch…

    (tags: alexa amazon echo-show devices home family)

  • CR2032 battery review

    IKEA-branded CR2032 batteries last about 70% as long as Duracell or Energizer, or 50% if your devices turn off at 2.7V

    (tags: cr2032 batteries data power via:itc ikea)

  • Big tech relies on refugee labour

    Holy shit this is dystopian.

    All of the largest companies in the world are today powered by a covert crowd of the system’s castoffs. Platforms have found amid those struggling to stay afloat in informal work — or else barely clinging onto a life in formal employment — a desperate mass to be tempted with the promise of a better life. Such a promise, however, is broken as soon as it is made; the petty services of the informal sector resemble little more than a blueprint for the microtasks of big tech, without offering anything in the way of rights, routine, role, security, or a future.

    (tags: colonialism refugees ai data machine-learning amazon google tesla uber mechanical-turk)

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Links for 2021-09-29

  • Partitioning GitHub’s relational databases to handle scale

    wow this is complex. Vitess playing a key part

    (tags: github mysql architecture database)

  • VR-based work setup

    “VR Productivity in (or above) a WFA world” —

    This week, I’ll spend 40–50 hours in Virtual Reality (Immersed), like I did last week and every (work) week for the last 2½ years. […] Yes, really: 8–10 hours a day strapped in.
    Basically, it’s using an Oculus Quest 2 to render multiple desktop displays from a laptop into a huge, full-visible-range virtual world:
    The resolution of these very large displays is surprisingly average—1080p (Reference, Communication) and 4k (Main). This makes the dot pitch unimpressive by the numbers, though still more than twenty-five times that of a roadside billboard display. Higher resolutions are available, but this is my calculated trade-off between pixel parity (more on that below), computer performance, and latency. Applications are tuned for readability and crispness, emphasizing information density over anti-aliasing or smoothness.
    The article sounds fairly solid, with good tips on how to make a VR headset suitable for constant daily use.

    (tags: oculus vr future work headsets display screens)

  • LEB128

    ‘a variable-length code compression used to store arbitrarily large integers in a small number of bytes.’

    (tags: encoding compression integers storage codes leb128)

  • Troll farms reached 140 million Americans a month on Facebook before 2020 election

    This is a staggering stat: “19 of Facebook’s top 20 pages for American Christians in 2019 were run by troll farms in Kosovo and Macedonia, internal documents leaked to MIT Technology Review reveal […] funded by the Russian Internet Research Agency.” (via Charlie Stross)

    (tags: facebook politics russia disinfo kosovo macedonia us-politics manipulation)

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Links for 2021-09-27

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Links for 2021-09-24

  • Do I have COVID or a cold?

    Data-driven results from the UK ZOE symptom survey!

    Currently, the most common COVID-19 symptoms in people who have been fully vaccinated […] are: Runny nose, Headache, Sneezing, Sore throat, Loss of smell (anosmia)
    And “loss of smell (anosmia) or loss of taste is still one of the most important predictors of testing positive for COVID-19 rather than a regular cold”.

    (tags: covid-19 colds health symptoms diseases zoe)

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Links for 2021-09-23

  • Steve Yegge on deprecation policies

    “Dear Google Cloud: Your Deprecation Policy is Killing You”:

    This lack of a support culture, combined with a “let’s break it in the name of making it prettier” deprecation treadmill, is alienating their developers. And that’s not a good thing if you want to build a long-lived platform. Google, wake the fuck up. It’s 2020. You are still losing. It’s time to take a hard look in the mirror and answer for yourselves whether you really want to be in the Cloud business. If you do, then stop breaking shit. You guys are rich. We developers are not. So when it comes to shouldering the burden of compatibility, you need to pay for it. Not us.
    This is absolutely correct — API deprecation is a lovely thing when you’re the one doing the deprecating, but it’s a disaster for the user experience, and sometimes that should be the most important thing.

    (tags: deprecation compatibility google apis support culture)

  • Managing Log Output in Buildkite

    Nice, simple way to collapse long log streams into collapsable/hidable sections, from BuildKite

    (tags: logging cli hacks buildkite streams)

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