Category: Women in Computing

Threads & Yarns – textiles and electronics

At first sight nothing could be more different than textiles and electronics. Put opposites together and you can maybe even bring historical yarns to life. That’s what Queen Mary’s G.Hack team helped do. They are an all-woman group of electronic engineering and computer science research students and they helped build an interactive art installation combining textiles and personal stories about health.

In June 2011 the G.Hack team was asked by Jo Morrison and Rebecca Hoyes from Central Saint Martins College of Art and Design to help make their ‘Threads & Yarns‘ artwork interactive. It was commissioned by the Wellcome Trust as a part of their 75th Anniversary celebrations. They wanted to present personal accounts about the changes that have taken place in health and well-being over the 75 years since they were founded.

Flowers powered

Jo and Rebecca had been working on the ‘Threads & Yarns’ artwork for 6 months. It was inspired by the floor tiling at the London Victoria and Albert Museum and was made up of 125 individually created material flowers spread over a 5 meter long white perspex table. They wanted some of the flowers to be interactive, lighting up and playing sounds linked to stories about health and well-being at the touch of a button.

Central Saint Martins College Textile students worked with senior citizens from the Euston and Camden area, recording the stories they told as they made the flowers. G.Hack then ran a workshop with the students to show them how physical computing could be built into textiles and so create interactive flowers. Short sound bites from the recorded stories were eventually included in nine of the flowers.

The interactive part was built using an open source (i.e., free and available for anyone to use) hardware platform called Arduino. It makes physical computing accessible to anyone giving an easy way to create programs that control lights, buttons and other sensors.

The audio stories of the senior citizens were edited down into 1-minute sound bites and stored on a memory card like those used in digital cameras. Each of the nine flowers were lit by eight Light Emitting Diodes (LEDs). They are low energy lights so they don’t heat up, which is important if they are going to be built into fabrics. They are found in most household electronics, such as to show whether a gadget is turned on or off. When a button is pressed on the ‘Threads & Yarns’ artwork, it triggers the audio of a story to be played and simultaneously lights the LEDs on the linked flower, switching off again when the audio story finishes.

Smooth operators

The artwork had to work without problems throughout the day so the G.Hack team had to make sure everything would definitely go smoothly. The day before the opening of the exhibition they did final testing of the interactive flowers in their electronics workshop. They then worked with Central Saint Martins and museum staff to install the electronics into the artwork. They designed the system to be modular. This was both to allow the electronics to be separate from the artwork itself as well as to ease combining the two. On the day of the exhibition, the team arrived early to test everything one more time before the opening. They also stayed throughout the day to be on call in case of any problems.

Leading up to the opening of the exhibition were a busy few weeks for G.Hack with lots of late nights spent testing, troubleshooting and soldering in the workshop but it was all worth it as the final artwork looked fantastic and received a lot of positive feedback from people visiting the exhibition. It was a really positive experience all round! G.Hack and Central Saint Martins formed a bond that will likely extend into future partnerships. ‘Threads & Yarns’ meanwhile is off on a UK ‘tour’.

Art may have brought the textiles, history and health stories together as embodied in the flowers. It’s the electronics that brought the yarn to life though.

Paul Curzon, Queen Mary University of London, June 2011

G.Hack

G.Hack was a supportive and friendly space for women to do hands-on experimental production fusing art and technology at Queen Mary University of London. As a group they aimed to strengthen each other’s confidence and ability in using a wide range of different technologies. They supported each other’s research and helped each other extend their expertise in science and technology through public engagement, collaborating with other universities and commercial companies.

The members of G.Hack involved in ‘Threads & Yarns’ were Nela Brown, Pollie Barden, Nicola Plant, Nanda Khaorapapong, Alice Clifford, Ilze Black and Kavin Preethi Narasimhan.

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3D models in motion

by Paul Curzon, Queen Mary University of London
based on a 2016 talk by Lourdes Agapito

Wireframe mesh image by Gerd Altmann from Pixabay

The cave paintings in Lascaux, France are early examples of human culture from 15,000 BC. There are images of running animals and even primitive stop motion sequences – a single animal painted over and over as it moves. Even then, humans were intrigued with the idea of capturing the world in motion! Computer scientist Lourdes Agapito is also captivated by moving images. She is investigating whether it’s possible to create algorithms that allow machines to make sense of the moving world around them just like we do. Over the last 10 years her team have shown, rather spectacularly, that the answer is yes.

People have been working on this problem for years, not least because the techniques are behind the amazing realism of CGI characters in blockbuster movies. When we see the world, somehow our brain turns all that information about colour and intensity of light hitting our eyes into a scene we make sense of – we can pick out different objects and tell which are in front and which behind, for example. In the 1950s psychophysics* researcher Gunnar Johansson showed how our brain does this. He dressed people in black with lightbulbs fastened around their bodies. He then filmed them walking, cycling, doing press-ups, climbing a ladder, all in the dark … with only the lightbulbs visible. He found that people watching the films could still tell exactly what they were seeing, despite the limited information. They could even tell apart two people dancing together, including who was in front and who behind. This showed that we can reconstruct 3D objects from even the most limited of 2D information when it involves motion. We can keep track of a knee, and see it as the same point as it moves around. It also shows that we use lots of ‘prior’ information – knowledge of how the world works – to fill in the gaps.

Shortcuts

Film-makers already create 3D versions of actors, but they use shortcuts. The first shortcut makes it easier to track specific points on an actor over time. You fix highly visible stickers (equivalent to Johansson’s light bulbs) all over the actor. These give the algorithms clear points to track. This is a bit of a pain for the actors, though. It also could never be used to make sense of random YouTube or CCTV footage, or whatever a robot is looking at.

The second shortcut is to surround the action with cameras so it’s seen from lots of angles. That makes it easier to track motion in 3D space, by linking up the points. Again this is fine for a movie set, but in other situations it’s impractical.

A third shortcut is to create a computer model of an object in advance. If you are going to be filming an elephant, then hand-create a 3D model of a generic elephant first, giving the algorithms something to match. Need to track a banana? Then create a model of a banana instead. This is fine when you have time to create models for anything you might want your computer to spot.

It is all possible for big budget film studios, if a bit inconvenient, but it’s totally impractical anywhere else.

No Shortcuts

Lourdes took on a bigger challenge than the film industry. She decided to do it without the shortcuts: to create moving 3D models from single cameras, applied to any traditional 2D footage, with no pre-placed stickers or fixed models created in advance.

When she started, a dozen or so years ago, making any progress looked incredibly difficult. Now she has largely solved the problem. Her team’s algorithms are even close to doing it all in real time, so making sense of the world as it happens, just like us. They are able to make really accurate models down to details like the subtle movements of their face as a person talks and changes expression.

There are several secrets to their success, but Johansson’s revelation that we rely on prior knowledge is key. One of the first breakthroughs was to come up with ways that individual points in the scene like the tip of a person’s nose could be tracked from one frame of video to the next. Doing this well relies on making good use of prior information about the world. For example, points on a surface are usually well-behaved in that they move together. That can be used to guess where a point might be in the next frame, given where others are.

The next challenge was to reconstruct all the pixels rather than just a few easy to identify points like the tip of a nose. This takes more processing power but can be done by lots of processors working on different parts of the problem. Key to this was to take account of the smoothness of objects. Essentially a virtual fine 3D mesh is stuck over the object – like a mask over a face – and the mesh is tracked. You can then even stick new stuff on top of the mesh so they move together – adding a moustache, or painting the face with a flag, for example, in a way that changes naturally in the video as the face moves.

Once this could all be done, if slowly, the challenge was to increase the speed and accuracy. Using the right prior information was again what mattered. For example, rather than assuming points have constant brightness, taking account of the fact that brightness changes, especially on flexible things like mouths, mattered. Other innovations were to split off the effect of colour from light and shade.

There is lots more to do, but already the moving 3D models created from YouTube videos are very realistic, and being processed almost as they happen. This opens up amazing opportunities for robots; augmented reality that mixes reality with the virtual world; games, telemedicine; security applications, and lots more. It’s all been done a little at a time, taking an impossible-seeming problem and instead of tackling it all at once, solving simpler versions. All the small improvements, combined with using the right information about how the world works, have built over the years into something really special.

*psychophysics is the “subfield of psychology devoted to the study of physical stimuli and their interaction with sensory systems.”

This article was first published on the original CS4FN website and a copy appears on pages 14 and 15 in “The women are (still) here”, the 23rd issue of the CS4FN magazine. You can download a free PDF copy by clicking on the magazine’s cover below, along with all of our free material.

Another article on 3D research is Making sense of squishiness – 3D modelling the natural world (21 November 2022).

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Nurses in the mist

by Paul Curzon, Queen Mary University of London

(From the archive)

A gorilla hugging a baby gorilla
Image by Angela from Pixabay

What do you do when your boss tells you “go and invent a new product”? Lock yourself away and stare out the window? Go for a walk, waiting for inspiration? Medical device system engineers Pat Baird and Katie Hansbro did some anthropology.

Dian Fossey is perhaps the most famous anthropologist. She spent over a decade living in the jungle with gorillas so that she could understand them in a way no one had done before. She started to see what it was really like to be a gorilla, showing that their fierce King Kong image was wrong and that they are actually gentle giants: social animals with individual personalities and strong family ties. Her book and film, ‘Gorillas in the Mist’, tells the story.

Pat and Katie work for Baxter Healthcare. They are responsible for developing medical devices like the infusion pumps hospitals use to pump drugs into people to keep them alive or reduce their pain. Hospitals don’t buy medical devices like we buy phones, of course. They aren’t bought just because they have lots of sexy new features. Hospitals buy new medical devices if they solve real problems. They want solutions that save lives, or save money, and if possible both! To invent something new that sells you ideally need to solve problems your competitors aren’t even aware of. Challenged to come up with something new, Pat and Katie wondered if, given the equivalent was so productive for Dian Fossey, perhaps immersing themselves in hospitals with nurses would give the advantage their company was after. Their idea was that understanding what it was really like to be a nurse would make a big difference to their ability to design medical devices. That helped with the real problems nurses had rather than those that the sales people said were problems. After all the sales people only talk to the managers, and the managers don’t work on the wards. They were right.

Taking notes

They took a team on a 3-month hospital tour, talking to people, watching them do their jobs and keeping notes of everything. They noted things like the layout of rooms and how big they were, recorded the temperature, how noisy it was, how many flashing lights and so on. They spent a lot of time in the critical care wards where infusion pumps were used the most but they also went to lots of other wards and found the pumps being used in other ways. They didn’t just talk to nurses either. Patients are moved around to have scans or change wards, so they followed them, talking to the porters doing the pushing. They observed the rooms where the devices were cleaned and stored. They looked for places where people were doing ad hoc things like sticking post it note reminders on machines. That might be an opportunity for them to help. They looked at the machines around the pumps. That told them about opportunities for making the devices fit into the bigger tasks the nurses were using them as part of.

The hot Texan summer was a problem

So did Katie and Pat come up with a new product as their boss wanted? Yes. They developed a whole new service that is bringing in the money, but they did much more too. They showed that anthropology brings lots of advantages for medical device companies. One part of Pat’s job, for example, is to troubleshoot when his customers are having problems. He found after the study that, because he understood so much more about how pumps were used, he could diagnose problems more easily. That saved time and money for everyone. For example, touch screen pumps were being damaged. It was because when they were stored together on a shelf their clips were scratching the ones behind. They had also seen patients sitting outside in the ambulance bays with their pumps for long periods smoking. Not their problem, apart from it was Texas and the temperature outside was higher than the safe operating limit of the electronics. Hospitals don’t get that hot so no one imagined there might be a problem. Now they knew.

Porters shouldn’t be missed

Pat and Katie also showed that to design a really good product you had to design for people you might not even think about, never mind talk to. By watching the porters they saw there was a problem when a patient was on lots of drugs each with its own pump. The porter pushing the bed also had to pull along a gaggle of pumps. How do you do that? Drag them behind by the tubes? Maybe the manufacturers can design in a way to make it easy. No one had ever bothered talking to the porters before. After all they are the low paid people, doing the grunt jobs, expected to be invisible. Except they are important and their problems matter to patient safety. The advantages didn’t stop there, either. Because of all that measuring, the company had the raw data to create models of lots of different ward environments that all the team could use when designing. It meant they could explore in a virtual environment how well introducing new technology might fix problems (or even see what problems it would cause).

All in all anthropology was a big success. It turns out observing the detail matters. It gives a commercial advantage, and all that mundane knowledge of what really goes on allowed the designers to redesign their pumps to fix potential problems. That makes the machines more reliable, and saves money on repairs. It’s better for everyone.

Talking to porters, observing cupboards, watching ambulance bays: sometimes it’s the mundane things that make the difference. To be a great systems designer you have to deeply understand all the people and situations you are designing for, not just the power users and the normal situations. If you want to innovate, like Pat and Katie, take a leaf out of Dian Fossey’s book. Try anthropology.

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Screaming Headline Kills!!!

A pile of newspapers
Image by congerdesign from Pixabay

Most people in hospital get great treatment but if something does go wrong the victims often want something good to come of it. They want to understand why it happened and be sure it won’t happen to anyone else. Medical mistakes can make a big news story though with screaming headlines vilifying those ‘responsible’. It may sell papers but it could also make things worse.

If press and politicians are pressurising hospitals to show they have done something, they may only sack the person who made the mistake. They may then not improve things meaning the same thing could happen again if it was an accident waiting to happen. Worse if we’re too quick to blame and punish someone, other people will be reluctant to report their mistakes, and without that sharing we can’t learn from them. One of the reasons flying is so safe is that pilots always report ‘near misses’ knowing they will be praised for doing so, rather than getting into trouble. It’s far better to learn from mistakes where nothing really bad happens than wait for a tragedy.

Share mistakes to learn from them

Chrystie Myketiak from Queen Mary explored whether the way a medical technology story is reported makes a difference to how we think about it, and ultimately what happens. She analysed news stories about three similar incidents in the UK, America and Canada. She wanted to see what the papers said, but also how they said it. The press often sensationalise stories but Chrystie found that this didn’t always happen. Some news stories did imply that the person who’d made the mistake was the problem (it’s rarely that simple!) but others were more careful to highlight that they were busy people working under stressful conditions and that the mistakes only happened because there were other problems. Regulations in Canada mean the media can’t report on specific details of a story while it is being investigated. Chrystie found that, in the incidents she looked at, that led to much more reasoned reporting. In that kind of environment hospitals are more likely to improve rather than just blame staff. How the hospital handled a case also affected what was written – being open and honest about a problem is better than ignoring requests for comment and pretending there isn’t a problem.

Everyone makes mistakes (if you don’t believe that, the next time you’re at a magic show, make sure none of the tricks fool you!). Often mistakes happen because the system wasn’t able to prevent them. Rather than blame, retrain or sack someone its far better to improve the system. That way something good will come of tragedies.

– Paul Curzon, Queen Mary University of London (From the archive)

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Playing the weighting game

by Paul Curzon, Queen Mary University of London

In the spotlight - bright lights dazzling in circles and stars
Image by Gerd Altmann from Pixabay

Imagine having a reality TV show where yet again Simon Cowell is looking for talent. This time it’s talent with a difference though, not stars to entertain us but ones with the raw ability to help find webpages. Yes, this time the budding stars are all words. Word Idol is here!

The format is simple. Each week Simon’s aim is to find talented words to create a new group: a group with star quality, a group with meaning. Like any talent competition, there are thousands of entries. Every word in every webpage out there wants to take part. They all have to be judged, but what do the specialist judges look for?

OK, we’re getting carried away. Simon Cowell may not be interested but there is big money in the idea. It’s a talent show that is happening all the time. The aim is to judge the words in each new webpage as it appears so that search engines can find it if ever someone goes looking. The real star of this show isn’t Simon Cowell but a Cambridge professor, Karen Spärck Jones. She came up with the way to judge words.

Karen worked out that to do this kind of judging a computer needs a thesaurus: a book of words. It just lists groups of words that mean the same thing. A computer, Karen realised, could use one to understand what words mean.

There is big money in the idea!

The fact that there are so many ways to say the same thing in human languages, makes it really hard for a computer to understand what we write. That is where a thesaurus comes in. If you ask a computer to search for web pages about whales, for example, it helps to know that, a page that talks about orcas is about whales too. Worse still, most words have more than one meaning, a fact that keeps crossword lovers in business.

Take the following example: “Leona is the new big star of the music business.”

The word ‘star’ here obviously means a celebrity, but how do you know? It could also mean a sun or a shape. The fact that it’s with the word ‘music’ helps you to work out which meaning is right even if you have no idea who or what Leona is. As Karen realised, a computer can also work out the intended meanings of words by the other words used with them. A thesaurus tells it what the critical groupings are, but what Karen wanted was a way a computer could work the thesaurus out for itself and now she had a way.

Her early approach was to write a program that takes lots and lots of documents and make lists of the words that keep appearing close together. If ‘music’ appears with ‘star’ lots then that is a new meaning. After building up a big collection of such lists of linked words, the program can then use it to decide which pages are talking about the same thing and so which ones to suggest when a search is done. So Karen had found the first way to judge whether a word has the right ‘talent’ to go in a group. The more often words appear together the higher the score or ‘weighting’ they should be given. Simple!

The only trouble is it doesn’t really work. That is where Karen’s big insight came. She realised that if two words appear together in a lot of different documents then, surprisingly perhaps, putting them together in a group isn’t actually that useful for finding documents! Do a search and they will just tell you that lots of web pages match. What you really want is to be told of the few web pages that contain the meaning you are looking for, not lots and lots that don’t.

The important word groupings are actually only in a small number of web pages. That suggests they give a very focused meaning. Word groups like that help you narrow down the search. So Karen now had a better way to judge word talent. Give high marks for pairs that do appear together but in as few web pages as possible. Rather than a talent show, it is more like a giant game of the quiz show Pointless where you win if you pick the words few other people did.

That idea was the big breakthrough and led to what is now called IDF weighting. It is the way to judge words, and is so good that it’s now used by pretty much every search engine out there. Playing the IDF weighting game may not make great TV but thanks to Karen it really does make for great web.

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Follow those ants

by Paul Curzon, Queen Mary University of London

Ants climbing on a mushroom obstacle course
Image by Puckel from Pixabay

Ant colonies are really good at adapting to changing situations: far better than humans. Sameena Shah wondered if Artificial Intelligence agents might do better by learning their intelligent behaviour from ants rather than us. She has suggested we could learn from the ants too.

Inspired by staring at ants adapting to new routes to food in the mud as a child, and then later as adult ants raided her milk powder, Sameena Shah studied for her PhD how a classic problem in computer science, that of finding the shortest path between points in a network, is solved by ant colonies. For ants this involves finding the shortest paths between food and the nest: something they are very good at. When foraging ants find a source of food they leave a pheromone (i.e., scent) trail as they return, a bit like Hansel and Gretel leaving a trail of breadcrumbs. Other ants follow existing trails to find the food as directly as possible, leaving their own trails as they do. Ants mostly follow the trail containing most pheromone, though not always. Because shorter paths are followed more quickly, there and back, they gain more pheromone than longer ones, so yet more ants follow them. This further reinforces the shortest trail as the one to follow.

There are lots of variations on the way ants actually behave. These variations are being explored by computer scientists as ways for AI agents to work together to solve problems. Sameena devised a new algorithm called EigenAnt to investigate such ant colony-based problem solving. If the above ant algorithm is used, then it turns out longer trails do not disappear even when a shorter path is found, particularly if it is found after a long delay. The original best path has a very strong trail so that it continues to be followed even after a new one is found. Computer-based algorithms add a step whereby all trails fade away at the same rate so that only ones still being followed stay around. This is better but still not perfect. Sameena’s EigenAnt algorithm instead removes pheromone trails selectively. Her software ants select paths using probabilities based on the strength of the trail. Any existing trail could be chosen but stronger trails are more likely to be. When a software ant chooses a trail, it adds its own pheromones but also removes some of the existing pheromone from the trail in a way that depends on the probability of the path being chosen in the first place. This mirrors what real ants do, as studies have shown they leave less pheromone on some trails than others.

Sameena proved mathematical properties of her algorithm as well as running simulations of it. This showed that EigenAnt does find the shortest path and never settles on something less than the best. Better still, it also adapts to changing situations. If a new shorter path arises then the software ants switch to it!

Sameena won the award
for the best PhD in India

There are all sorts of computer science uses for this kind of algorithm, such as in ever-changing computer networks, where we always want to route data via the current quickest route. Sameena, however, has also suggested we humans could learn from this rather remarkable adaptability of ants. We are very bad at adapting to new situations, often getting stuck on poor solutions because of our initial biases. The more successful a particular life path has been for us the more likely we will keep following it, behaving in the same way, even when the situation changes. Sameena found this out when she took her dream job as a Hedge Fund manager. It didn’t go well. Since then, after changing tack, she has been phenomenally successful, first developing AIs for news providers, and then more recently for a bank. As she says: don’t worry if your current career path doesn’t lead to success, there are many other paths to follow. Be willing to adapt and you will likely find something better. We need to nurture lots of possible life paths, not just blindly focus on one.

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Mary Clem: getting it right

by Paul Curzon, Queen Mary University of London

Mary Clem was a pioneer of dependable computing long before the first computers existed. She was a computer herself, but became more like a programmer.

A tick on a target of red concentric zeros
Image by Paul Curzon

Back before there were computers there were human computers: people who did the calculations that machines now do. Victorian inventor, Charles Babbage, worked as one. It was the inspiration for him to try to build a steam-powered computer. Often, however, it was women who worked as human computers especially in the first half of the 20th century. One was Mary Clem in the 1930s. She worked for Iowa State University’s statistical lab. Despite having no mathematical training and finding maths difficult at school, she found the work fascinating and rose to become the Chief Statistical Clerk. Along the way she devised a simple way to make sure her team didn’t make mistakes.

The start of stats

Big Data, the idea of processing lots of data to turn that data into useful information, is all the rage now, but its origins lie at the start of the 20th century, driven by human computers using early calculating machines. The 1920s marked the birth of statistics as a practical mathematical science. A key idea was that of calculating whether there were correlations between different data sets such as rainfall and crop growth, or holding agricultural fairs and improved farm output. Correlation is the the first step to working out what causes what. it allows scientists to make progress in working out how the world works, and that can then be turned into improved profits by business, or into positive change by governments. It became big business between the wars, with lots of work for statistical labs.

Calculations and cards

Originally, in and before the 19th century, human computers did all the calculations by hand. Then simple calculating machines were invented, so could be used by the human computers to do the basic calculations needed. In 1890 Herman Hollerith invented his Tabulator machine (his company later became computing powerhouse, IBM). The Tabulator machine was originally just a counting machine created for the US census, though later versions could do arithmetic too. The human computers started to use them in their work. The tabulator worked using punch cards, cards that held data in patterns of holes punched in to them. A card representing a person in the census might have a hole punched in one place if they were male, and in a different place if they were female. Then you could count the total number of any property of a person by counting the appropriate holes.

Mary was being more than a computer,
and becoming more like a programmer

Mary’s job ultimately didn’t just involve doing calculations but also involved preparing punch cards for input into the machines (so representing data as different holes on a card). She also had to develop the formulae needed for doing calculations about different tasks. Essentially she was creating simple algorithms for the human computers using the machines to follow, including preparing their input. Her work was therefore moving closer to that of a computer operator and then programmer’s job.

Zero check

She was also responsible for checking calculations to make sure mistakes were not being made in the calculations. If the calculations were wrong the results were worse than useless. Human computers could easily make mistakes in calculations, but even with machines doing calculations it was also possible for the formulae to be wrong or mistakes to be made preparing the punch cards. Today we call this kind of checking of the correctness of programs verification and validation. Since accuracy mattered, this part of he job also mattered. Even today professional programming teams spend far more time checking their code and testing it than writing it.

Mary took the role of checking for mistakes very seriously, and like any modern computational thinker, started to work out better ways of doing it that was more likely to catch mistakes. She was a pioneer in the area of dependable computing. What she came up with was what she called the Zero Check. She realised that the best way to check for mistakes was to do more calculations. For the calculations she was responsible for, she noticed that it was possible to devise an extra calculation, whereby if the other answers (the ones actually needed) have been correctly calculated then the answer to this new calculation is 0. This meant, instead of checking lots of individual calculations with different answers (which is slow and in itself error prone), she could just do this extra calculation. Then, if the answer was not zero she had found a mistake.

A trivial version of this general idea when you are doing a single calculation is to just do it a second time, but in a different way. Rather than checking manually if answers are the same, though, if you have a computer it can subtract the two answers. If there are no mistakes, the answer to this extra check calculation should be 0. All you have to do is to look for zero answers to the extra subtractions. If you are checking lots of answers then, spotting zeros amongst non-zeros is easier for a human than looking for two numbers being the same.

Defensive Programming

This idea of doing extra calculations to help detect errors is a part of defensive programming. Programmers add in extra checking code or “assertions” to their programs to check that values calculated at different points in the program meet expected properties automatically. If they don’t then the program itself can do something about it (issue a warning, or apply a recovery procedure, for example).

A similar idea is also used now to catch errors whenever data is sent over networks. An extra calculation is done on the 1s and 0s being sent and the answer is added on to the end of the message. When the data is received a similar calculation is performed with the answer indicating if the data has been corrupted in transmission. 

A pioneering human computer

Mary Clem was a pioneer as a human computer, realising there could be more to the job than just doing computations. She realised that what mattered was that those computations were correct. Charles Babbages answer to the problem was to try to build a computing machine. Mary’s was to think about how to validate the computation done (whether by a human or a machine).

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Fran Allen: Smart Translation

Cars making light pattterns at night Image by Светлана from Pixabay
Image by Светлана from Pixabay

Computers don’t speak English, or Urdu or Cantonese for that matter. They have their own special languages that human programmers have to learn if they want to create new applications. Even those programming languages aren’t the language computers really speak. They only understand 1s and 0s. The programmers have to employ translators to convert what they say into Computerese (actually binary): just as if I wanted to speak with someone from Poland, I’d need a Polish translator. Computer translators aren’t called translators though. They are called ‘compilers’, and just as it might be a Pole who translated for me into Polish, compilers are special programs that can take text written in a programming language and convert it into binary.

The development of good compilers has been one of the most important advancements from the early years of computing and Fran Allen, one of the star researchers of computer giant, IBM, was awarded the ‘Turing Prize’ for her contribution. It is the Computer Science equivalent of a Nobel Prize. Not bad given she only joined IBM to clear her student debts from University.

Fran was a pioneer with her groundbreaking work on ‘optimizing compilers’. Translating human languages isn’t just about taking a word at a time and substituting each for the word in the new language. You get gibberish that way. The same goes for computer languages.

Things written in programming languages are not just any old text. They are instructions. You actually translate chunks of instructions together in one go. You also add a lot of detail to the program in the translation, filling in every little step.

Suppose a Japanese tourist used an interpreter to ask me for directions of how to get to Sheffield from Leeds. I might explain it as:

“Follow the M1 South from Junction 43 to Junction 33”.

If the Japanese translator explained it as a compiler would they might actually say (in Japanese):

“Take the M1 South from Junction 43 as far as Junction 42, then follow the M1 South from Junction 42 as far as Junction 41, then follow … from Junction 34 as far as Junction 33”.

Computers actually need all the minute detail to follow the instructions.

The most important thing about computer instructions (i.e., programs) is usually how fast following them leads to the job getting done. Imagine I was on the Information desk at Heathrow airport and the tourist wanted to get to Sheffield. I’ve never done that journey. I do know how to get from Heathrow to Leeds as I’ve done it a lot. I’ve also gone from Leeds to Sheffield a lot, so I know that journey too. So the easiest way for me to give instructions for getting from London to Sheffield, without much thought and be sure it gets the tourist there might be to say:

Go from Heathrow to Leeds:

  1. Take the M4 West to Junction 4B
  2. Take the M25 clockwise to Junction 21
  3. Take the M1 North to Leeds at Junction 43

Then go from Leeds to Sheffield:

  1. Take the M1 South to Sheffield at Junction 33

That is easy to write and made up of instructions I’ve written before perhaps. Programmers reuse instructions like this a lot – it both saves their time and reduces the chances of introducing mistakes into the instructions. That isn’t the optimum way to do the journey of course. You pass the turn off for Sheffield on the way up. An optimizing compiler is an intelligent compiler. It looks for inefficiency and actually converts it into a shorter and faster set of instructions. The Japanese translator, if acting like an optimizing compiler, would actually remove the redundant instructions from the ones I gave and simplify it (before converting it to all the junction by junction detailed steps) to:

  1. Take the M4 West to Junction 4B
  2. Take the M25 clockwise to Junction 21
  3. Take the M1 North to Sheffield Junction 33

Much faster! Much more intelligent! Happier tourists!

Next time you take the speed of your computer for granted, remember it is not just that fast because the hardware is quick, but because, thanks to people like Fran Allen, the compilers don’t just do what the programmers tell them to do. They are far smarter than that.

Paul Curzon, Queen Mary University of London (Updated from the archive)

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EPSRC supports this blog through research grant EP/W033615/1. 

A gendered timeline of technology

(Updated from previous versions, July 2025)

A pocket watch in the sand
Image by Annette from Pixabay

Women have played a gigantic role in the history of computing. Their ideas form the backbone to modern technology, though that has not always been obvious. Here is a gendered timeline of technology innovation to offset that.

825 Muslim scholar Al-Khwarizmi kicks it all off with a book on algorithms – recipes on how to do computation pulling together work of Indian mathematicians. Of course back then it’s people who do all the computation, as electronic computers won’t exist for another millennium.

1587 Mary, Queen of Scots loses her head because the English Queen, Elizabeth I, has a crack team of spies that are better at computer science than Mary’s are. They’ve read the Arab mathematician Al-Kindi’s book on the science of cryptography so they can read all Mary’s messages. More

1650 Maria Cunitz publishes Urania Propitia an updated book of astronomical tables based on the ones by Johannes Kepler. She gives an improved algorithm over his for calculating the positions of the planets in the sky. That and her care as a human computer make it the most accurate to date. More.

1757 Nicole-Reine Lepaute works as a human computer as part of a team of three calculating the date Halley’s comet will return to greater accuracy (a month) than Halley had (his prediction was over a year).

1784 Mary Edwards is paid as a human computer helping compile The Nautical Almanac, a book of data used to help sailors work out their position (longitude) at sea. She had been doing the work in her husband’s name for about 10 years prior to this.

1787 Caroline Herschel becomes the first woman to be paid to be an astronomer (by King George III) as a result of finding new comets and nebulae. She goes on to spend 2 years creating the most comprehensive catalogue of stars ever created to that point. This involves acting as a human computer doing vast amounts of computation calculating positions.

1818 Mary Shelley writes the first science fiction novel on artificial life, Frankenstein. More

1827 Mary Web publishes the first ever Egyptian Mummy novel. Set in the future, in it she predicts a future with robot surgeons, AI lawyers and a version of the Internet. More

1842 Ada Lovelace and Charles Babbage work on the analytical engine. Lovelace shows that the machine could be programmed to calculate a series of numbers called Bernoulli numbers, if Babbage can just get the machine built. He can’t. It’s still Babbage who gets most of the credit for the next hundred-plus years. Ada predicts that one day computers will compose music, A century or so later she is proved right. More

1854 George Boole publishes his work on a logical system that remains obscure until the 1930s, when Claude Shannon discovers that Boolean logic can be electrically applied to create digital circuits.

1856 Statistician (and nurse) Florence Nightingale returns from the Crimean War and launches the subject of data visualisation to convince politicians that soldiers are dying in hospital because of poor sanitation. More

1912 Thomas Edison claims “woman is now centuries, ages, even epochs behind man”, the year after Marie Curie wins the second of her two Nobel prizes.

1927 Metropolis, a silent science fiction film, is released. Male scientists kidnap a woman and create a robotic version of her to trick people and destroy the world. The robotic Maria dances nude to ‘mesmerise’ the workers. The underlying assumptions are bleak: women with power should be replaced with docile robots, bodies are more important than brains, and working class men are at the whim of beautiful gyrating women. Could the future be more offensive?

1931 Mary Clem starts work as a human computer at Iowa State College. She invents the zero check as a way of checking for errors in algorithms human computers (the only kind at the time) are following.

1941 Hedy Lamarr, better know as a blockbuster Hollywood actress co-invents frequency hopping: communicating by constantly jumping from one frequency to another. This idea underlies much of today’s mobile technology. More

1943 Thomas Watson, the CEO of IBM, announces that he thinks: “there is a world market for maybe 5 computers”. It’s hard to believe just how wrong he was!

1945 Grace Murray Hopper and her associates are hard at work on an early computer called Mark I when a moth causes the circuit to malfunction. Hopper (later made an admiral) refers to this as ‘debugging’ the circuit. She tapes the bug to her logbook. After this, computer malfunctions are referred to as ‘bugs’. Her achievements didn’t stop there: she develops the first compiler and one of the pioneering programming languages. More

1946 The Electronic Numerical Integrator and Computer is the world’s first general purpose electronic computer. The main six programmers, all highly skilled mathematicians, were women. They were seen to be more capable programmers because it was considered too repetitive for men and as a result it was labelled ‘sub-professional’ work. Once more men realised that it was interesting and fun, programming was re- classed as ‘professional’, the salaries became higher, and men become dominant in the field.

1949 A Popular Mechanics magazine article predicts that the computers of the future might weigh “as little as” 1.5 tonnes each. That’s over 10,000 iPhones!

1958 Daphne Oram, a pioneer of electronic music, co-founds the BBC Radiophonic Workshop, responsible for the soundscapes behind hundreds of tv and radio programmes. She suggests the idea of spatial sound where sounds are in specific places. More

1966 Paper published on ELIZA, the first chatbot that in its psychotherapist role, people treat as human. It starts an unfortunately long line of female chatbots. It is named after a character from the play Pygmalion about a working class woman taught to speak in a posh voice. The Greek myth of Pygmalion is about a male sculptor falling in love with a statue he made. Hmm… Joseph Weizenbaum agrees the choice was wrong as it stereotyped women.

1967 The original series of TV show Star Trek includes an episode where mad ruler Harry Mudd runs a planet full of identical female androids who are ‘fully functional’ at physical pleasure to tend to his whims. But that’s not the end of the pleasure bots in this timeline…

1969 Margaret Hamilton is in charge fo the team developing the in-flight software for the Apollo missions including the Apollo 11 Moon Landing. More.

1969 DIna St Johnston founds the UKs first independent software house. It is a massive success writing software for lots of big organisations including the BBC and British Rail. More.

1972 Karen Spärck Jones publishes a paper describing a new way to pick out the most important documents when doing searches. Twenty years later, once the web is up and running, the idea comes of age. It’s now used by most search engines to rank their results.

1972 Ira Levin’s book ‘The Stepford Wives’ is published. A group of suburban husbands kill their successful wives and create look-alike robots to serve as docile housewives. It’s made into a film in 1975. Sounds like those men were feeling a bit threatened.

1979 The US Department of Defence introduces a new programming language called Ada after Ada Lovelace.

1982 The film Blade Runner is released. Both men and women are robots but oddly there are no male robots modelled as ‘basic pleasure units’. Can’t you guys think of anything else?

1984 Technology anthropologist Lucy Suchman draws on social sciences research to overturn the current computer science thinking on how best to design interactive gadgets that are easy to use. She goes on to win the Benjamin Franklin Medal, one of the oldest and most prestigious science awards in the world.

1985 In the film Weird Science, two teenage supergeeks hack into the government’s mainframe and instead of using their knowledge and skills to do something really cool…they create the perfect woman. Yawn. Not again.

1985 Sophie Wilson designs the instruction set for the first ARM RISC chip creating a chip that is both faster and uses less energy than traditional designs: just what you need for mobile gadgets. This chip family go on to power 95% of all smartphones. More

1988 Ingrid Daubechies comes up with a practical way to use ‘wavelets’, mathematical tools that when drawn are wave-like. This opens up new powerful ways to store images in far less memory, make images sharper,
and much, much more. More

1995 Angelina Jolie stars as the hacker Acid Burn in the film Hackers, proving once and for all that women can play the part of the technologically competent in films.

1995 Ming Lin co-invents algorithms for tracking moving objects and detecting collisions based on the idea of bounding them with boxes. They are used widely in games and computer-aided design software.

2004 A new version of The Stepford Wives is released starring Nicole Kidman. It flops at the box office and is panned by reviewers. Finally! Let’s hope they don’t attempt to remake this movie again.

2005 The president of Harvard University, Lawrence Summers, says that women have less “innate” or “natural” ability than men in science. This ridiculous remark causes uproar and Summers leaves his position in the wake of a no-confidence vote from Harvard faculty.

2006 Fran Allen is the first woman to win the Turing Award, which is considered the Nobel Prize of computer science, for work dating back to the 1950s. Allen says that she hopes that her award gives more “opportunities for women in science, computing and engineering”. More

2006 Torchwood’s technical expert Toshiko Sato (Torchwood is the organisation protecting the Earth from alien invasion in the BBC’s cult TV series) is not only a woman but also a quiet, highly intelligent computer genius. Fiction catches up with reality at last.

2006 Jeannette Wing promotes the idea of computational thinking as the key problem solving skill set of computer scientists. It is now taught in schools across the world.

2008 Barbara Liskov wins the Turing Award for her work in the design of programming languages and object-oriented programming. This happens 40 years after she becomes the first woman in the US to be awarded a PhD in computer science. More

2009 Wendy Hall is made a Dame Commander of the Order of the British Empire for her pioneering work on hypermedia and web science. More

2011  Kimberly Bryant, an electrical engineer and computer scientist founds Black Girls Code to encourage and support more African-American girls to learn to code. Thousands of girls have been trained. More

2012 Shafi Goldwasser wins the Turing Award. She co-invented zero knowledge proofs: a way to show that a claim being made is true without giving away any more information. This is important in cryptography to ensure people are honest without giving up privacy. More

2015 Sameena Shah’s AI driven fake news detection and verification system goes live giving Reuters an advantage of several years over competitors. More

2016 Hidden Figures, the film about Katherine Johnson, Dorothy Vaughan, and Mary Jackson, the female African-American mathematicians and programmers who worked for NASA supporting the space programme released. More

2018 Gladys West is inducted into the US Air Force Hall of Fame for her central role in the development of satellite remote sensing and GPS. Her work directly helps us all. More

2025 Ursula Martin is made a Dame Commander of the Order of the British Empire for services to Computer Science. She was the first female Professor of Computer Science in the UK focussing on theoretical Computer Science, Formal Methods and later maths as a social enterprise. She was the first true expert to examine the papers of Ada Lovelace. More.

It is of course important to remember that men occasionally helped too! The best computer science and innovation arise when the best people of whatever gender, culture, sexuality, ethnicity and background, disabled or otherwise, work together.

Paul Curzon, Queen Mary University of London

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EPSRC supports this blog through research grant EP/W033615/1.