Aerospace Challenge Finals at Cranfield

Last week I was in Cranfield participating in the Aerospace Challenge Finals. The challenge this year was to come up with a design for a device to drop humanitarian aid accurately (within 20 metres of a target) from 3000 metres up. Our idea managed to make it to the finals which turned out to be a week of lectures on general aerospace engineering, activities and flying! Photos are here.

Flying

Each person got two flying experiences, both of which included some time piloting the aircraft: about 10-20 minutes in a helicopter and about half an hour in a fixed-wing plane.

My first flying experience was with a small Robinson helicopter, which can only really be described as terrifyingly, exhilaratingly awesome. The pilot managed the take-off which was one of the most breathtaking experiences I’ve ever had – in a helicopter you’re literally sitting in a big transparent flying bubble with the engine behind you, so the view and experience is truly amazing as the land falls away beneath you… I later took over and found control extremely difficult – even a tiny movement of the stick causes the vehicle to tilt violently in that direction making a beginner like me very prone to overcorrection leading to a serious case of increasing-amplitude SHM! The actual stick is situated between the pilot and the copilot and a rotating handle is stuck on the end allowing dual control, so my rather flailing and uncontrolled flight was abruptly and expertly rectified when the pilot took control (though not before I turned and prepared to land by erratically lurching towards a patch of grass). The pilot then demonstrated some cool things one can do with a helicopter including skid landing and take-off, going backwards and sideways while spinning etc.

Here you can see how control over steering is shared between pilot (me) and real pilot (instructor)

The next day I got in a PA28 – my first fixed-wing experience. The pilot had to go through an enormous list of things to check before taking off and explained a little about what she was doing (mostly checking the engine could rev at certain RPMs and wouldn’t give out in certain situations, flicking on and off various lights and calibrating [and pointing at] instruments). The runway was also ridiculously long so she didn’t even bother with flaps for takeoff. This was much easier to fly than the helicopter and the dials and instruments in the cockpit didn’t obscure the view as much I had inferred they would from MS Flight Sim’s portrayal. I did a few rather ginger turns and pitch adjustments before relinquishing control back to the pilot who then demonstrated some steep banks, a stall (which sounded dangerous and seemed to imply the engine cutting out) and a dive (which was extremely cool). Later that week Matthew and I were inspired enough to ask about possible places to get flying instruction – flying has always been one of those things I’ve wanted to learn but I’ve always ended up not having enough time or money to start…

Here the instructor is doing a steep bank. She even did a pretty steep dive totally relaxed and with that pen in her hand!

Me flying the PA28!

Activities

The week started with some group leadership exercises which consisted of attempting to place 30 cards in the correct pattern (easy) and work out the shape and colour of two missing shapes while blindfolded (hard) – both were much more enjoyable than I had expected from that genre of exercises.

The first engineering challenge we were given was an egg-drop challenge – the idea was to construct a package which will protect an egg from a drop of 4 metres. We were given limited materials and each material had a price; the idea was to make the cheapest package that doesn’t crack the egg. Our attempt turned out to be the most epic non-fail in history – literally seconds before the end of the construction phase we managed to pop two balloons which made us completely change our plan and in the last few seconds and in great haste we crammed stuff into a crumple zone and added a parachute … and it somehow worked and turned out to be the cheapest package (if wastage is deducted)! I guess that really proves the KISS principle: Keep It Simple Stupid.

The second engineering challenge was along similar lines – dropping aid – though it was from a more macro perspective. The game was called ‘airlift’ and sold by Elite – the idea was to plan an air route through several African villages which uses the least fuel, while dropping packages of aid which we had to construct out of wooden blocks, paper and tape while making sure everything fits in the cargo hold. The first thing I pointed out when time started was that both problems were NP-complete: the packing problem was almost exactly the same as the knapsack problem and the route planning was basically the Travelling Salesman problem with fuel added in as a factor. In other words we had to be either very good at intuitive problem solving or somehow get lucky. As it turned out, as perhaps a combination of the two, we somehow managed to come up with both the the optimum packing configuration as well as the best route, and finished literally as the final buzzer went – not bad!

The rest of the week was dotted with things like paper plane competitions (which included an awesome flying paper ring which seems impossible when you first see it fly), a game of (actual) CTF and some sports.

Lectures

Over the week there were daily lectures. Much as I would love to discuss them all here in depth I haven’t got that much time / space and besides most people aren’t as interested as I am in the effect of negative angles of attack… But I’ll go a little into some of the most interesting lectures.

Fly by Wire (FBW)

The problem for a long time had been that when going sufficiently quickly, adjusting the controls from the cockpit was really quite hard work – the air going past has so much momentum and the mass flow rate is so high that to change its direction by (for example) adjusting the ailerons requires a lot of force. To make things worse, at supersonic speeds a shock cone is developed (some awesome videos of this are on Youtube) – if this touches the aileron the stick can be wrenched out of the pilot’s hand. Some of these controls were partially solved by making the stick adjust small tabs in the wing instead of the entire aileron, reducing the force required to steer, and by making controls non-reversible (force on the aileron doesn’t affect the flying stick). There are of course some problems with these such as lack of ‘feel’ of the controls. So recently manual stick-aileron transmission was replaced with an electronic motor which receives instructions from the cockpit and adjusts the ailerons itself. Not only does this take all the strain off the pilot, but it also allows a computer to neutralise bad judgements on the part of the pilot such as initiating a sharp dive at 50 feet, implemented by a feedback mechanism from the aircraft to the computer. It also simplifies the cockpit – instead of filling the area with controls, dials an instruments, a computer screen with a joystick and throttle suffices to fly a FBW plane. I asked whether, since FBW significantly reduces the pilot’s direct control over the aircraft, FBW might actually make complicated manouevres more unsafe or indeed completely impossible. John Farley, who was giving the talk, said that, from his vast experience, pilots, however experienced, cannot really be trusted to fly planes safely all the time, and in fact he would feel safer trusting a computer’s judgement and letting a computer do such manouevres than a pilot. That talk also proves that a Boeing 747 probably has non-reversible controls so that scene in Snakes on a Plane (I think it was that film) in which the pilot asked the co-pilot to help pull back on the stick very hard was probably a load of rubbish. Not that you needed to be told that.

Basic Aerodynamics

One of the interesting things from this talk was the reasoning for why helicopters don’t go fast. There is always one part of the rotor going forwards, and if the helicopter moves forwards sufficiently quickly that part of the rotor travels at supersonic speeds generating a shockwave that could rip apart the rotor. In addition, even at lower speeds, there is an imbalance between the airspeed of the fowards-going part and backwards-going part of the rotor meaning a gimbal has to change the angle of attack of the blade depending on which way it’s going: the angle of attack of the rearwards-going blade has to increase to increase lift on that side otherwise the helicopter would just roll over. Of course, there is a maximum angle of attack this blade can be set to before it stalls which is about 20°. This limits the helicopter’s speed at subsonic speeds.

An RAF Hawk landed at the airstrip for us - here is the pilot demonstrating how the entire tailplane rotates

Automation and the future

This was probably the most interesting talk of the week; unfortunately it was cut short for us owing to a jetstream flight. Apparently currently pilots of Euro Fighters get sensor fused info presented to them in the form of advice as to what to do and they simply act upon that, which means half the time the plane is telling the pilot what to do: it is telling the pilot how to control it: semi-automation. Even in commercial aircraft a system called TCAS (Traffic Collision Avoidance System) senses other aircraft and advises the pilot on how to manoeuvre. There is clearly room for improvement: unmanned aerial vehicles are coming. This of course led to the whole humans v computers discussion but for every example of a pilot doing something heroic and saving the plane, there are several examples in which pilots screwed up and computers would have saved lives – Chris Roberts, the speaker, asked whether it *really* is desirable to have a pilot flying the plane, and whether the problem of pilots becoming de-skilled from letting the autopilot take over really is such a problem after all. I also found it very interesting and surprising that currently many landings of commercial aircraft are performed by the autopilot in low-visibility situations.

Anyways overall it was a fantastic week. Whatever the results of the competition turn out to be, I for one got a lot out of six days in Cranfield. I learnt a lot, made some friends, made some good contacts in the industry, and had some great fun relaxing in the English countryside!

Walking in the English countryside

Microsoft Work Experience – Half Time

I’m currently doing Work Experience at Microsoft Research in Cambridge (MSR Cambridge) and despite my gripes about Microsoft software, the research centre and some of the stuff people are doing there is pretty cool. Here’s what I’ve done so far and what I think of the place / stuff.

I arrived in Cambridge to a 4-storey house all to myself (!) complete with dishwasher, washing machine, decent cooking stuff etc. I saw the wifi router but it wasn’t broadcasting beacons – it was a hidden SSID. So I spent about 3 hours capping packets to no avail on a nearby WEP wifi and finally realised that (a) there was an ethernet cable sticking out of the wifi router which I could plug into, and (b) the router had its hidden SSID written on it.

After waking up the next day to three alarms (alarm clock, laptop, watch; 5 minutes apart from each other; I wanted to make sure I actually got up on time … for once) I left my laptop at home with three layers of Lifehacker-inspired protection (physical lock, Yawcam for motion detection webcam and LaptopAlarm – a thief would have to have his/her photo uploaded to an FTP server and walk around Cambridge with a chest of drawers attached to a laptop that starts screaming the second it’s unplugged in order to steal my laptop) and walked the 1.6 mile commute to MSR in the West Cambridge Site NW of the city. I eventually arrived where I was issued a temporary pass, a Microsoft Research rucksack, some freebies and a ‘wottle’ – MS in an attempt to do the environment some good decided to issue refillable recycled plastic/rubber (?) bottles. The person who came up with the idea evidently had the same lack of aptitude as I do when it comes to names; it’s got ‘wottled by you’ written on the side…

I also met my supervisor who explained a little about what the project I was to be working on (Infer.NET in the machine learning area) is all about – Bayesian inference. It’s basically a system of statistical modelling which takes in information about distributions, observed values and interaction between random variables and infers new distributions by applying Bayes’ Theorem (which SJRH gave us a talk in the dying weeks of term). In terms of the theory all he said was when there are several distributions it gets pretty complicated and uber-badass integration (not his words) is necessary which, until an approximate method was found a couple of years ago, wasn’t really possible computationally. He also introduced me to a couple of the team members, one of whom has a firm belief that random variables should be a part of programming and are as valid as, if not more than, ‘normal’ everyday data types like integers.

Eventually we settled on my project. I’d mentioned the Monty Hall problem when discussing Bayes’ Theorem and he proposed that I work on a display implementing that using Infer.NET as a simple project, and also to give me an idea of how something like that would be implemented using this framework. At that point I was more or less left to my own devices to familiarise myself with the workstation and Visual Studio and to complete a stack of paperwork I’d been given. I think it was at about this point that I discovered I was working on an 8-core Dell Precision workstation. Serious overkill – as Guy pointed out, probably employees spend most of their time gaming and consequently don’t get much done!

My supervisor (I think the legal paperwork of which there was much permits me to give his name – John Guiver) took me out for lunch according to some sort of tradition involving new people joining the team at the Cavendish Laboratory Canteen (the Cavendish Lab was near the MS building). Actually the canteen there was pretty standard (I was expecting wonders from the great Cavendish) though the food is good and cheap – that’s all that really matters. One of the other team members, John Winn (random variables in programming dude) had been to MIT. Apparently they have whiteboards in the loos and people leave each other problems on them, sangaku style!

There was some sort of filming going on in the main lecture theatre – bright white theatre floodlights adorned the roof and several cameras were propped up on tripods all over the place. After lunch I ended up agreeing to help out which mostly involved milling around displays of Infer.NET related programs for a time lapse vid. This turned out to be really awesome because of the way the displays were implemented – massive multi-touch touch screen coffee tables! They could also be operated by circular counters placed on the tabletop, used like dials (twist to change settings), similar to a touch screen I’d seen on youtube demonstrating a physics simulator. There was also a(n incomplete) machine vision display which proudly labeled a pair of scissors as a book…

Afterwards I grabbed myself the Infer.NET dll’s and started trying to implement the Monty Hall problem. There was a problem with the model and I ended up (wilfully) working almost an hour overtime on my first day! I got home and tried for the first time (and failed) to play Dawn of War Soulstorm with Guy over Hamachi-induced WAN.

Thursday was a particularly interesting day. The first thing that happened was, while infuriated with WPF’s apparent inability to do frame by frame animations and in a *very* roundabout method of doing things, I worked out how to do multithreading in C#. It’s not actually that hard at all (1 line of code captures the essence of it) but was just one of those really useful things I’d always wanted to learn but hadn’t owing to preconceptions about ploughing through hundreds of lines of unclear example code from an obscure online tutorial. Traditionally Thursday lunch is an Infer.NET group lunch so I also got to chat more with the rest of the team about what they’re doing. One was trying to help a mathematician with something programmatic and was stressing about why on earth he kept insisting on doing things in unprogrammatic and ultimately unsuccessful ways, which ended up as a big discussion about mathematical v computing methods, and how the two disciplines have drastically different approaches and concepts of ideal solutions despite their fundamental similarities. It also allowed me to use my rather scanty knowledge of linear algebra to justify the mathematician’s approach to writing an algorithm to determine if a graph has loops: create the graph’s incidence matrix and find its determinant. If the det is zero the graph has a loop. Of course finding the determinant is an O(n³) affair using Gauss Jordan (exponential if you use the FP1-style cofactor method) so computationally expensive . Thursday afternoon saw my discovery of how to make dlls in C# using Visual Studio, the second simple yet important discovery of the day.

But most interesting / fun was the evening. A go karting event had been arranged for all the interns (and some employees) as part of a summer series of events and as a work experience employee I’d been invited. I discovered I wasn’t the only first timer which made me feel a little less worried about failing epically; so long as the damn thing doesn’t have a clutch I’ll be OK (just had my second driving lesson). Anyways it was all a lot of fun – I only crashed once because I first overestimated then underestimated the tyres’ grip (it was a classic understeer-oversteer-skid affair) and didn’t lean the right way (apparently you should lean towards the outside of a bend to get more grip which seems to me as a cyclist extremely counterintuitive). I also discovered it’s true that racing makes you ridiculously thirsty; luckily I had my wottle to hand! Afterwards while we were waiting for the coach back I noticed one of the employees was wearing a T-shirt with ‘i bing’ on the front and ‘u bing?’ on the back – apparently people who had worked on the Bing project were all issued them at the launch.

By Friday I’d more or less finished the Monty Hall implementation, so John and I discussed possibilities for next week. One was some intelligent text ‘understanding’ which uses a neat little trick involving Bayesian inference on a massive scale to partition a text into phrases (without using punctuation as a guide). Another alternative was to use statistical analysis on the relative locality of certain words to generate a summary of a very long text. I suggested the possibility of using Infer.NET for auto correcting which seemed viable. I was also led over to the uber-cool gadgets area of the building (‘computers in the home’) which was densely populated with enormous screens, multi-touch touch screen coffee tables, wireless [just about everything] and more or less all the stuff I’d want to have sitting in my room!

John also explained a little about modelling statistics and factor graphs: graphs in which nodes are either variables or functions, and edges are directed. Messages in the form of entire distributions are passed along these edges between the variables and functions and you end up getting complicated-looking graphs with arrows and squares and rectangles. These are used for describing models and the maths is apparently beyond 1st year undergrad… The storm that day was also quite epic – the electricity in the MS building seemed affected as the lights kept flickering out – I assume the PCs were all UPS’d.

Anyways those are my thoughts at half time – I still have another week to go. I haven’t actually taken [m]any photos at all since I’ve been spending most of my hours either working or cooking/eating or sleeping (I’m back in London for the weekend); hopefully I’ll be able to take some next week.

Snowdonia Walking Trip

I’ve just (yesterday) returned from the annual walking trip (this year to Snowdonia) in the mountainous midge breeding ground that is Wales. I managed to write a brief record of our daily activities so here is (more or less) an illustrated account of our adventures.

I’m trying out Picasa as an alternative to Flickr so all the photos I’ve published of this trip are in my Picasa Web Album.

Sunday: Journey up

This was rather boring until we stopped at Betws-y-Coed (the teachers pronounced it roughly as ‘Battersea Coyd’ – I’m pretty sure that’s wrong) for lunch. It appeared that they were having some sort of summer festival so we grabbed some burgers and sausage rolls from a rather smokey and carcinogenic-looking stand and sat on a bench contemplating a police car that appeared to be on show (pop music emanated from its speakers, its sirens went off at apparently random intervals, and members of the public kept crawling in and out of the car while two police officers stood nearby sipping pints), a madman standing in a fenced area wielding a chainsaw (there was a sign saying ‘wood carving’ though the ‘toadstools’ that he produced were arguably less aesthetic than the original stumps) and a van with ‘water incident unit’ painted on its side (we postulated it had something to do with rescuing vehicles / people from lakes, hence the dry suits hanging up inside. I prefer the hypothesis that it rushes to the rescue whenever it rains and erects a large umbrella). We sauntered further into the town and saw the railway station, though we decided the ice cream shop was far more interesting.

We left Betws-y-Coed and passed by Beddgelert (where the most awesome and famous ice cream shop of Wales is) where we saw this rather amusing advert on the back of a bus:

Amusing advert on the back of a bus as we went over the bridge in Beddgelert

Finally we pulled into the campsite with Queen blasting through the minibus’ stereo and set up our tents in the otherwise deserted campsite.

Abuse of a mallet for hammering in tent pegs

In the absence of KPZ, it was GL’s turn to cook – dinner was rather good but plagued by a flashmob of midges (which lasted for the next six days). We 8th formers did the washing up to set an example and returned to find the entire campsite had been invaded by a small battalion of siege cows.

Easily visible in the backgound is a herd of cattle that somehow managed to get into the campsite.

We retreated from the insect-mammal assault into the minibus (where we could observe the campsite owner attempting to chase the cows off his land with a quad bike) and played a game of mafia (very difficult in a minibus). We eventually got to bed at around 10-11 pm.

Monday: Light walk, blazing sun

Everyone was awoken by the dawn chorus at the unholy hour of 6am – if not for the cows joining in I might have been able to get some more sleep before the planned 8am breakfast, at which GL described the previous night’s cooking as ‘look[ing] like a polluted river’: he’d cooked it in Specked Hen which created a substantial amount of froth…

Alastair looking triumphant at the top of the mountain

People in Wales seem to have a great sense of humour. We'd also seen a sign in Betws-y-Coed saying 'Children left unattended will be sold to the circus'

We split into three groups for the walk, after which two groups stopped by at Beddgelert for ice cream. DAE decided to pull an amusing trick on GL: since GL had already parked when we (DAE’s bus) had arrived, with endorsement from TCIM (‘what could go wrong?’) DAE moved GL’s bus somewhere inconspicuous and parked our bus in its spot, and went as far as transferring GL’s sandals to DAE’s bus! After a most satisfactory ice cream we watched mirthfully through binoculars from an unsubtle distance as GL became increasingly stressed!

Several hours after we returned to the campsite, we witnessed the much anticipated arrival of Max and Marius, two OPs who left the U8 last year but wanted to join us for a laugh. After dinner we all sat in the TV room and watched one of the most drawn-out tennis competitions I have ever seen which lasted until 10:30 and resulted in Murray winning 6-3 (I think). It was about then that I discovered the campsite offered free wifi and began downloading the missed episode of Top Gear (S13 E02).

Tuesday: Snowdon

The weather was perfect on the ascent: it was cloudy and breezy which made walking uphill effortless and chilled. As we reached the top we began the customary cursing of fat tourists sitting at the top of Snowdon wearing snow white trainers who had evidently taken the train up but still had the impudence to buy badges and T-shirts with words to the effect of ‘I walked up Snowdon’. Suggestions were made about using the fattest ones as train fuel (!), making the train treadmill-powered, not providing a train journey back down the mountain, and stopping the train half way up Snowdon, forcing everyone to do some work before reaching the top. I was also disappointed by the lack of free drinking water at the cafe – apparently tap water there is straight from the lake.

DAE found / remembered a tunnel off the beaten track which led to an abandoned quarry

Max & Marius appear to have found a rather good vantage point

The train to the top of Snowdon seems to run partly on steam though the actual lifting is probably a rack and pinion affair. I don't really know much about trains...

We were fortunate and managed to get a pretty good view (not much mist)

The descent was extremely hot and humid which made most of us feel like jumping into the remarkably clear plunge pools of the river running alongside the path. GL was keen to return quickly to the campsite to grab meat for a BBQ that night so we would have been unable to grab an ice cream from Beddgelert if not for a rather timely and extremely spectacular incident involving the contents of a 5th former’s stomach and several people around the epicentre who took some … splash damage. This event occurred precisely outside the ice cream shop, forcing DAE to do an emergency stop in the shop’s car park. I jokingly suggested to the Reverend (who was with us on that trip) that God must have really wanted us to have an ice cream. Max and Marius arrived and chauffeured GL away to do some meat shopping leaving us with the rather iconic image of a grinning Max sitting in the back seat clutching two double ice cream cones. That evening after the BBQ some of us watched Top Gear and played Dawn of War on my laptop until about 11pm.

DAE found a (slightly shorter) shortcut down Snowdon

When you're hot and sweaty it is unbelievably tempting to just jump in...

Sir we found a reverend!

Wednesday: Cnicht

When I was on the same trip three years ago this was the first day mountain. On Wednesday we approached it from a different face which involved quite a lot of scrambling. It was hot and humid but the steep ascent and striking view from the top made it all worth it and not much of a slog. We made our customary stop at Beddgelert for another ice cream, then we downloaded and watched ‘Night at the Museum’ (both I and II).

There was a pretty awesome view from the top of Cnicht. According to Marius the name Cnicht means Viking Helmet which is what the mountain resembles from the sea

Don't fall off!

A helicopter appeared while we were descending Cnicht and the friendly guy waved at us. None of us dared wave back lest we be mistaken for hikers in distress

Thursday: Beach / Campsite

We awoke to the soothing (or alarming, depending on who you are) sound of a torrent merrily splashing onto the tops of our tents. The weather forecast was unpromising so we had the option of going to the beach or staying at the campsite (by now there were several people feeling unwell from the heat of the previous days). Max and Marius left (but not before tearful goodbye hugs from everyone who happened to be around), and Guy and I stayed at the campsite (I wanted to get on with some reading and he played an 8-way dawn of war battle). I ended up cooking a rather sumptuous sausages and eggs for us at which point I discovered what a mess the kitchen was.

Dinner was lamb, mushrooms and potatoes with cake dessert, after which we watched Alien v Predator 2 until midnight. It had rained most of the afternoon and night.

Friday: Half-day walk, getting lost

We woke up to an extremely wet morning so we cowered in the communal tent for breakfast. We had lunch in the campsite then ventured out in the sunny afternoon to where we had gone the previous trip to do orienteering. We got lost several times, and I managed to get a large number of amusing photos of our leaders peering confusedly at the map. Most of my downhill journey was spent making witty banter with the Reverend about religion terminating in us finally agreeing on where we were on the map. Again the trip ended in ice cream at Beddgelert, and we returned at about 5:45 to the campsite where we discovered rather rude campers had decided to pitch their tent between the school minibus and our tents!

Here are several pictures of our group leaders getting extremely lost:

… and the absolute classic (caption competition anyone?):

After GL’s slightly tipsy Scheherazade (all teachers are young at heart, especially after a few pints!) some of us congregated in the TV room to watch Saw (which seemed to have quite an impact on the subject of conversations for the rest of the trip) followed by Jonathan Ross interviewing Emma Watson. I then made some attempts at taking night photos before going to bed.

Saturday: Rainy walk

We woke up for the third day in a row to torrid rain, but at 10:30 the teachers decided we might was well do a walk around the base of Tryfan. The highest point of the walk was extremely windy and wet making for freezing horizontal rain. We lunched inside the (extremely) orange emergency shelter which wasn’t quite large enough for all of us which caused us some entertainment. We also got a bit of a laugh from imagining people outside asking a heaving, seething, complaining, munching orange mass in the middle of the footpath on the side of a mountain whether it was OK, and whether it had seen a party of six people walk past!

Eventually the sun came out and even though we’d been shivering some of the way down the mountain we decided an ice cream at Beddgelert was called for (I went for a double cone: Chocolate & Ginger and Run & Raisin).

At 5pm the internet was abruptly cut off while I was downloading Saw II and we were told we’d been downloading too much and were using up the monthly cap. We’d been getting 600KB/s; I knew there had to be a catch. So instead of watching a film we rebuilt our dam from three years ago I took some more photos.

The classic trick with rapids - take a long exposure. For some of these I had to put the stand in the middle of the stream - I hope it doesn't rust

Sunday: Journey back

There’s not much to say about yesterday: we packed everything up, woke the apparently unwakeable 6th formers and helped them pack their tent, and drove back to London. We all cheered when we saw the sign welcoming us into Shropshire at the Welsh-English border and listened to Queen’s Greatest Hits as we coasted down the bus lane on the M4.

Final Thoughts

I thought it was an altogether highly enjoyable trip. The mounds of earth that had segregated our part of the campsite from everyone else three years ago were gone and there was no electricity near our tents which was a slight inconvenience, and I felt too many days were rained off / taken lightly … but overall I think most people had a great time, nothing / nobody got broken, and it was a great way to relax after the end of a tough school year.

Meanwhile – this is too good not to repeat:

Perhaps if someone thinks up a good caption … ?

๏̯͡๏﴿

British Informatics Olympiad Finals at Cambridge

I’ve just got back from the British Informatics Olympiad finals (they chose the top 14 in the country to take this – I was an experimental error) which took place at Trinity College in Cambridge. Despite a fairly epic fail, I thought the weekend was quite productive and I’ve definitely acquired better skills from the only formal or otherwise training in programming the contestants were (strongly) encouraged to undertake. More photos can be found on my Flickr photostream.

Night shot of housing

As always with such activities, the people there shared many interests, and since programming is (at St Paul’s anyway) an interest few people take vaguely seriously, it was a particularly unique weekend for me in that I could talk about Dijkstra’s Algorithm without getting suspicious sideways glances and a general awkward diffusion of human density away from myself… Pretty much all the people there were doing double Maths and were very much into it, and even at a school like St Paul’s one probably wouldn’t be able to mention the Collatz Conjecture and have every person in the room nod and begin elucidating their own hypotheses on where the proof will (if ever) eventually come from (e.g. graph theory, number theory, computing etc). One of the people who had a big hand in organising and managing the whole affair (Tom), seemed to know a great deal about Physics, Maths and computing and the night before the olympiad he and a few of us had a long argument about string theory, something unheard of even in Physics lessons at school. Tom also seemed to know my maths teacher from helping him set ridiculously hard BMO questions at some point in the past (I think I can just about forgive him for doing that). The atmosphere was also quite singular since geek humour actually worked, and maths and physics jokes got a higher laugh:groan ratio than usual; though I couldn’t help facepalming when, while collecting in papers, Tom remarked ‘all your papers are belong to us’.

I think I probably did get quite a bit out of this whole experience. Since being invited to the finals I’ve been constantly prodded to complete USACO training challenges which are combined with a form of structured training / algorithmic tutorial thing which gives users formal training of algorithms. This training is actually the only time I’ve ever been ‘trained’ in programming and I’d been sort of making things up on the fly since I started programming (in visual basic…) back in Colet Court – I didn’t actually know what a greedy algorithm was until this year, and my understanding of even what algorithms are was still sketchy when I took the BIO for the second time (last year). So by going through a beginners through intermediate algorithms training course was definitely useful for me and I now approach problems more analytically rather than just trying to convince a compiler to automatically do what I would personally do if faced with a problem (no, not give up straight away and watch a film instead). I have to say though that despite its utility I acquired a few bad habits from it. Since for each assignment infinite attempts are allowed, I tend not to actually test programs against anything other than sample data and submit it, hoping something that can solve a specific case will probably work with all other cases. Inevitably it tends not to work first time and rather than sitting down and debugging it, I take the test data and just try to make the program work for that by doing silly things like making loops slightly longer or incrementing variables by 1 randomly. USACO helpfully also provides the full answers for test data. I have to say though that the grading system on USACO is impressive – after you submit a solution the backend code automatically compiles and runs the program for each test case and grades its answer. Inspired, I’ve now got something vaguely similar set up on my Debian server (albeit requiring both FTP and SSH connections to sort of do everything manually).

Another thing I’ve always wanted to do was learn C++ as every linux package seems to require compilation with g++, so C/C++ seems to be the language to learn. Since the BIO Finals required code in C/C++ or Delphi (that nobody used, surprise surprise) I was forced to learn a new language, and after discovering the awesomeness of pointers, I have an incentive to endure the confusion and use some really cool programming features (at the risk of corrupting random critical data in the system memory).

And as always with a visit to Cambridge, I got to see more of the college and living quarters. I have to say, the Corpus rooms were more spacious though assuming a specific comparison is representative of a more general comparison would be displeasing to my stats teacher.

And of course since the BIO is sponsored by Lionhead Studios (gaming company) we got to meet a representative and should find obtaining work experience there much easier.

So anyway, here’s what I remember from the itinerary:

Day 1
Erroll and I arrived at Trinity only to be told we had to be at the porters of Burrell College on Grange Road, which is somehow related to Trinity. After a bit of a trek we arrived, Pauline-style, fashionably late. We were shown our rooms, were provided with food and were shown the computer rooms where we got used to our environments. It was actually a very simple question on summing squares repeatedly (up to 2^63 times) – all we had to do was notice there was a repeating sequence – but the unfamiliar environment and unfamiliar method of file input (fscanf in <stdio> as opposed to fin >> in <fstream>) made me do all sorts of stupid things. I think after three months of USACO challenges in C++ I think I still prefer C# / Java as languages. Perhaps it’s got something to do with compilers (my 2003 MS C++ compiler at home goes kaput randomly).

Day 2
The brain uses an insane amount of energy when working hard and doing olympiads was even suggested (as a joke) as a means of weight loss. For this reason an awesome breakfast was bestowed upon us, consisting of baconey, eggy, toastey goodness. The morning papers were both written, the first being on Turing Machines and the second on emotion/sentiment detection in text. This was actually probably the most enjoyable part of the contest – the questions on turing machines were a bit like a mix of maths, logic and electronis (involving truth table like things and train track systems etc). It was also the only bit I could actually seem vaguely competent doing – an education in maths and electronics probably helped me.

The afternoon was when the hardcore competitioning kicked in with a whopping five-hour paper consisting of four questions (the best people completed two questions). I’ll talk about those later, but I failed quite epically, only managing to write a program to solve a question for about half the test data. It also transpired I’d spent all my time on the hardest question, and that although I saw immediately an algorithm that Dr Forster said worked, my implementation was total crap. Later that evening I managed to think up a linear time program to solve the same problem which when I mentioned it the next morning was apparently the best solution Dr Forster had thought of. I still blame C++

After the olympiad I attempted to take some night photography with a tripod which is apparently banned. Oops. We all then went to dinner at Ask and got quite stuffed up before being asked to eat more in the chill room afterwards.

Day 3
Today was mostly free time in which Erroll, I and another person we met spent our 2 hours of free time pulling newspaper, broadband adverts and IR spectra printouts out of a pool table in an attempt to get the balls out. Our efforts included using mobile phones as endoscopes to get a better view of the inside of the machine, using wire coat hangers as hooks to reach the newspaper and peering inside the machine to aid our end. We were eventually thwarted as we concluded our over-zealous table tilting had resulted in the balls falling out of the mechanism entirely and ending up unretrievably on the bottom of the table. For future reference: pool table lock picking doesn’t work with coat hanger wires.

After an inventive method of going round (in three dimensions) a gate without a keycard I and a few others got to the main Trinity college. The tension was apparently high as they announced the IoI competitors though I didn’t notice; my expectations were clearly low as I had just organised three weeks’ work experience with Microsoft at the same time as the finals. What was nice though was that we got very cool 4GB memory sticks with ‘British Informatics Olympiad’ on them, and we were issued with compulsory free games and ‘Introduction to Algorithms’. I already had the book and had in fact brought it to the contest in order to seem vaguely intelligent with no real intention of looking at it.

My room

The questions

I’ve put thumbnails of scans – click to enlarge. I cut out my retarded scribblings.

Desperate Measures

This is the one I half did, and also the hardest. You’re given a cross section of a polygon and are supposed to divide it into triangles using only given vertices. In the question the polygon is the cross section of a cave tunnel…

My initial (and apparently correct) thought was to cut off all the bits sticking out of the polygon (i.e. turn them into triangles and ignore the outside points) and end up with a convex polygon and subsequently just a triangle in the middle; sort of repeatedly going round the polygon chopping off bits. My second (and apparently better) thought was to go from left to right joining up points, an algorithm that runs in linear time.

River

This is apparently the easiest question: a river (= straight line) of up to length 2^31 kilometres (the unit was some amusing invented thing but I can’t remember what it was) can be split up in one of up to 1000 (=n) ways into n unequal segments (= up to 1000 different sections using up to 1000 different partitions). The question was to split it into n segments so that each different segment is a segment described in a different partition and there’s no overlap of partitions. OK that’s a crap explanation – the scan does it better.

I didn’t actually look at this which is a pity – it was the easiest. When I looked at it before going to bed that night I managed to come up with an algo straight away which would have worked in O(n^2 ish) – the biggest case would have taken about a second to run. Pity I saw 2^31 and immediately moved on when actually doing the competition.

All work and no play

The scan says it all. It was a really annoying question because I started working on it about an hour before the end. I wrote an efficient O(n) algo for finding how many ways there are of making n in such a way, had an amazing pascal’s triangle/combinatorics thing going, and was about to write it when I realised it all got screwed up by the blocks only going up to 10. Unable to repair my program, my final submission only worked up to n=10 (needs to work up to n=64). I might also have forgotten to change the output method from console to file output. Meh.

Spies

I couldn’t think of an efficient way of doing this (not even in the evening though I was very sleepy by then) and am certainly not going to attempt it again until I have lots of free time, i.e. summer. This was the second hardest.

๏̯͡๏﴿

Cambridge Eng + Comp Sci Lectures

Today was the fourth time I’ve been to Cambridge (bringing my total by the end of this year to six, as I mentioned here), this time for another CareersMCS event about engineering and computer science. Like both the other conferences organised by the same people, I ended up leaving somewhat inspired, and wanting to do all the courses they talked about. As one of my friends put it, now I don’t want to be a banker/medic/programmer/whatever – I just want to be a student all my life. As Chef from South Park put it, “there’s a time and place for everything … and it’s called college”.

The day started at silly o’clock when I woke up, arriving in time for a 9:45 start. After an intro (at the beginning of which all parents in the hall were, as always, assertively invited to leave – presumably to allow us to feel free to ask questions) we launched straight into Aerospace Engineering.

I feel I took away something new, interesting and possibly useful from each of the nine lectures today. Aerospace was all about fluid dynamics and how aerofoils generate lift, footballs spin and paper aeroplanes do ‘loop-de-loops’. The speaker quickly dismissed the higly yesteryear longer path theory (and to think I was misled by the Science Museum!) and moved onto explaining exactly what Cambridge professors think is going on. It’s all about bends in streamlines creating pressure gradients and subsequent forces. Theories involving Bernoulli’s speed-pressure relationships are also apparently flawed. Fluid dynamics are one of the Physics topics tragically lost in the teaching of AS Physics (*very* casually touched upon by KPZ when we were calculating electron drift speeds in wires) so it was certainly something novel for me to see.

The speaker touched on the intriguing Physics behind shock fronts and sonicbooms

Computer science was largely familiar to me – it was on security: mostly cryptography and corresponding cryptanalysis, but also briefly touching on stego, social engineering and PGP certs. It’s interesting to note that contrary to what I might have expected a year ago, the course places little emphasis on learning programming languages such as C++ well, but far more about simply working out algorithms and computational methods for solving problems. Having now done some (sort of) formal algorithm training (and being aware of the syntax of many different types of languages), I’m seeing the language divide beginning to melt away and starting to see the use of teaching, say, Dijkstra’s Algorithm in pseudocode rather than C++. And of course, it was no surprise that Mathematics (particularly llinear algebra) played a pretty hefty role.

Chemical engineering was quite a new one for me since I hadn’t a clue what it was all about beforehand. Turns out it’s essentially process engineering. After this we were given a time-lag-style summary of a first-year student’s perspective on applying to engineering at Cambridge. Following lunch was an intriguing talk on mechanical engineering involving some familiar circular motion revision and a pretty awesome demo of a Morrison Shelter, with the speaker’s mobile phone as collateral (sitting inside a flimsy-looking metal-wire shelter as a 5KG weight was dropped on it)! This was followed by an excellent demo-rich talk on electrical engineering (I was delighted to be able to recognise an AS-style power amp, albeit one with three concatenated push-pull amplifiers [power!]) which revised some electromag physics (dPhi/dt, I(lxB), q(vxB) etc). There were also some nice experiments with a big coil and an iron rod going through it – though I felt rather sad about being so delighted by seeing Physics demonstrated so wonderfully. Maybe I’m just weird that way…

Morrison Shelter. It used concepts of plasticity to reduce damage to occupants (like car crumple zones)

The talk on applications of IT to engineering was highly interesting theoretically though the program appeared depressingly slow – crunching a few matrix equations would have taken MATLAB about five seconds at the most. The speaker left his program running for a good half of his talk before it finally finished… The guy in charge gave a talk on applying and UCAS and other such helpful stuff in which he cracked the same joke as he does for every single one of these: apparently someone wrote on his personal statement [paraphrased]:

I do lots of music. I enjoy playing the flute; sometimes I play with myself

The day was concluded with a talk on civil engineering, though by that time my brain was complaining about lack of sleep.

The thing I love about studying things like Physics and Maths is that every now and then as I learn new topics and areas in the subjects, I come across proofs and lines of logical thinking and generally ‘things’ which just make me stop and think, ‘oh yeah – never thought about it that way before’, and marvel at the genius of whoever came up with it (for example OLCT told us about an intriguing interpretation of regression lines involving dot products of vectors). Maths and Physics have intriguing subtleties which never fail to inspire. I still think after today that I’ll go with Physics/Maths. Engineering subjects are interesting and probably far more directly useful practically speaking. But there were moments in the lectures when I felt the subjects were more superficial than I would like. There’s just something about delving deep into a subject and finding something surprising and counter-intuitive yet logically beautiful that makes me want to find out more. I must be *really* weird…

Again, as I was walking around Cambridge, I observed huge contrasts in the types of people around. There’s something I love about students – they make up the most diverse age group: the norm is to be radically different and anti-trendy. The town is simply buzzing full of life, from street musicians (pretty good ones as well!) to punters (literally), to human rights demonstrators sitting in cages outside King’s. This time we also got to see Corpus, Trinity and St John’s all on the same street, the three colleges about which I know enough to want to apply to. Cambridge is simply an awesome place; there’s no question about it.

Is Everything about Cambridge?

By the end of this academic year it looks like I’ll have visited Cambridge (the university in England that is; not the MIT/Harvard area) 5 times: twice last year, and thrice this year; and that’s assuming plans don’t change to include extra school trips, Headstart courses, open days etc. which may well boost this number to 7. Contrastingly, the number of times I’ve ever been to Oxford is currently zero and it seems (unfortunately for me) like it’s going to stay that way for the rest of the foreseeable future. The thing I find strange is that pretty much all of these visits were/are to attend events, rather than for the sake of visiting the university, which seems to indicate to me that stuff related to areas I’m interested in seems to prefer to take place in Cambridge rather than Oxford, which if true would have obvious ramifications for my future university choices.

In hindsight this is probably my best-composed photo of The Chronophage, a recent addition to Corpus Christi's library frontend

A quick run-through of Cambridge trips, past and future, just to make sure I’m not deluding myself: Last year I visited the city for my first time with my parents. the point of the trip was actually cycling in the countryside but we couldn’t resist having a look round the place and absorbing the scholarly atmosphere of the top^{[citation needed ]} university in the UK. Much later on in the year I learnt of a CareersMCS conference thing on NatSci. At the time I was fairly ambivalent about what to study at university, apart from the (rather strong) feeling that I wanted to do something scientific. But I turned up, at Churchill College I think, and was *almost* persuaded to do Biology at AS to study some of the intriguing-sounding courses they talked about … until someone explained the tripos system and informed us that Biology AS/A2 isn’t necessary for any of the courses (including ‘Biology’) so apparently as a means to getting into a course it isn’t a very good choice.

Corpus Christi, Cambridge (hideously underexposed). The grass is exclusively for college members to recline on although when we were there we were urged to do just that...

This year Cambridge infiltrated my life almost as soon as I settled into the first term. Dr Zetie decided that the four Physics Challenge gold-medallists from last year (who coincidentally all received the same mark, were all in his set, and had their papers all marked by him) were to go to Cambridge to attend the annual ‘Senior Physics Challenge’ which turned out to be a series of lectures on circular motion and special relativity which spanned two days and included a night in a Corpus Christi apartment. I enthused about the whole experience and thought that would be the last I’d see of Cambridge before I apply next year. Then at the end of last term I sat the British Informatics Olympiad, a fairly hardcore three hour programming olympiad exam, and was overjoyed to discover that I had by some fluke managed to come top 15 in the country and was invited to the finals. To my further delight, I learned that these finals were to take place at Trinity College – Cambridge; this time I’m to stay two nights. Finally, by some fantastical spot of luck, I managed to get work experience at Microsoft^®©™ which I’m told only happens to PhD students. They have five research centres / labs around the world, and the one in the UK closest to me … isn’t in Oxford. Possibly three weeks. Maybe the trend will continue and I’ll be living in Cambridge in two years’ time. I sure hope so…

3D Model of Cambridge

So what is it about Cambridge that makes me virtually frequent it? I suspect this trend is simply a confirmation of a suspicion I’ve had since some time ago. There was a time when I thought Oxford was simply better in every way – more famous, better education, better courses. I was actually disappointed to discover that Stephen Hawking wasn’t at Oxford. That time was quite a while ago – back in the year when I still rowed and Oxford (I think) won the boat race. Ever since, I’ve been exposed to a general consensus of bias against Oxford amongst the Sciencey and Mathsey cliques at St Paul’s which I attempted to ignore until my interview for the Arkwright Scholarship when the interviewer, an engineer, was extremely insistent about ‘correcting’ my hopes to apply to ‘Oxbridge’ to ones to apply to ‘Cambridge’. So is Cambridge the better university for my interests, as I suspect? The three main areas I’m currently considering for university are Maths, Physics and Computing/Computer Science/Informatics (rumour has it that there’s a distinction between the three apparent synonyms). The first thing anyone thinks of when someone says to him/her ‘Maths at University’ is ‘Trinity’, and Mark Warner at Corpus Christi (Physics) is one of the most inspiring lecturers I’ve seen in action. I’ve also heard of a legendary Anson Cheung at Trinity of whom my Physics teachers speak very highly. When I was talking with my university advisor about the possibility of doing Computer Science and Maths, a search on the UCAS website for a joint Maths/Computer Science course yielded results for Cambridge, Imperial, Bristol and Oxford amongst others, yet he only remarked about the first three of those universities.

My poor point-and-shoot skills don't do Cambridge justice

So Cambridge it is? I think I will almost definitely apply there. It has a beautiful campus, fantastic lecturers, inspired students, a wonderful atmosphere and (apparently) good wifi. Clearly I’m in no position to pass judgement on which university out of Oxford and Cambridge is ‘better’, merely which one I’m more sure will suit me. And from what I’ve seen of Cambridge, as Farhan put it, it’s like I’ve found where I really belong (provided I stand a chance of getting in of course – STEP – yikes).

On the other hand I’m currently half way through a series of SAT exams for American universities and have my sights trained on Stanford, MIT, Princeton… I’ve also been watching a series of MIT lectures on matrices and linear algebra (Prof. Gilbert Strang) which is simply awesome stuff (the way apparently unrelated concepts seem to come together, like the link between dimensions of nullspaces and number of solutions to simultaneous equations, matrices and Kirchoff’s Laws, nullspace and solutions to SHM second order differential equations). So if I end up with a choice between Stanford and Cambridge that would be just indescribably good. So to answer my question, for the UK, Cambridge it definitely is. But the US simply offers so much good stuff in terms of universities (sometimes with unbelievably generous financial aid) that it would be criminally foolish for me not to apply.

Right. Now, back to doing work that might actually vaguely contribute towards that daydream…

A beautiful boulevard-style path we walked down while lost during a lunch break at the Senior Physics Challenge

Shanghai: First Impressions

I’ve only been in Shanghai for a bit and have just about got over jet lag. I ended up doing an all-nighter last night, taking some night shots of the cityscape from my (highly elevated) bedroom window and watching the smoggy sunrise in awe, just to get my sleep-cycle right and ended up snoring through a Chinese music concert in the evening – oops… So, first impressions.

Immediately after touchdown, the first thing to greet my sleep-deprived eyes was a colourful and gleeful rendering of the cheerful glory of an olympic host, painted onto the side of a member of the China Airlines fleet. Up till now, that remains the only apparent relic I’ve seen of last Summer’s excitement.

Beijing 2008 Advert

As I expected, apart from the airport which was magnificent and unbelievably (to a Londoner) efficient (somewhat different from dear old Heathrow), there are aspects of this place which are somewhat … different. The most striking part is probably the population density. Officially Shanghai has a population of about 20 million, although I suspect that figure is a gross underestimate owing to the number of homeless and unregistered civilians living in this district. With such a population squashed into only 6500 square Km, the city has over 3000 people per square kilometre. Not bad one might think, but the crowds are multitudinous and dense. It is a result of this crowd culture that Chinese people get their (deserved) loud reputation. Even in the most serene places, people will communicate at top volume, choosing to shout rather than to talk normally so as to be heard. Walking around just about anywhere constitutes shoving your way through a throng of people – which itself wouldn’t be so bad if they were normal people. The sad fact is that every person here, without exception, appears to be dying of some disease or other and every line of sight seems to end in someone spluttering, coughing and/or blowing his nose into the air. Hygiene awareness when coughing and sneezing (often while cooking) is approximately zero – bodily fluids/gases exit bodily orifices liberally into the open air without thought or care for anyone unfortunate enough to be nearby. Combined with such a high person to square kilometre ratio and you end up with a fantastic disease spread rate. The smoking situation is also quite chronic. The taxi from the airport reeked blatantly of cigarette smoke. Crowds emit smoke puffs as you push your way through and buildings stink of nicotine. Oh, did I mention the pollution? Don’t get me started on the smog.

typical crowded street

my photo of the iconic view of Shangai showing smog

me cynically photographing more smog

Meanwhile, the traffic is absolutely manic. Shanghai is very much a biking city (electric scooters and bicycles are much cheaper than cars), and such vehicles, when combined with a cavalier disregard for pedestrians, traffic lights and other road users, make for quite deadly weapons. Crossing the road is like waging a war. Seas of pedestrians from both sides of the road meet in the middle in a cacophony of shouting, bustling, coughing and spitting while being constantly punched through by honking road bikes and the occasional impatient taxi. Sometimes there’s a policeman in the middle of it all pretending to direct traffic (both pedestrian and vehicular). There are effectively no real rules for the road. Cars cut lanes and cross junctions at full speed without warning or looking around, and diesel motorbikes frequently mount pavements, pushing aside pedestrians. My dad while he was here personally bore witness to an accident in which an infelicitous pedestrian was hit by a car whose driver just drove off, without care for whatever mess he had left behind. You’d think people would at least take out some sort of physical insurance against such a dangerous road situation, but it seems that taxis deliberately disable seatbelts (the ones I’ve been in have had them ripped out and covered over with cloth).

My camera can only do max 4 second exposure. This is the result

no seatbelt

When most people think of the police, the first two words that jump to mind tend to be ‘law’ and ‘bastards’, often in reverse order. In China, things are very different. During my very first trip to the market I saw a policeman grab an item from a shop and stroll away calmly with the ill-fated shopkeeper running after him, tugging his arm. They are far from law, but they sure are bastards. There are no rules, no morals, and few properly enforced civil rights laws (thoughtcrime law on the other hand…) – the police are just bullies with sticks and uniforms (and guns).

As far as first impressions go, the internet actually isn’t bad. I’m using the [still censored] connection in my dad’s apartment (he works in Shanghai) and the upload speed is faster than what Virgin Media give me back home in good old London. The download speed, about 1Mbps, is still one tenth what I get in London, which is still perfectly ample for surfing. Remote desktop on the other hand is torturous. I’m still worried about thoughtcrime and censorship, and since my blog is on the blocklist (well, all wordpress blogs are, I think) I’m typing this up on Notepad and subsequently posting it through remote desktop.

There are though good things about Shanghai. I’m overdramatising the bads a bit as, well, that’s what I do as a cynic. But the prices are undeniably good and conversion is convenient (10Y = £1 almost exactly). Stuffed bao (sort of buns) go for 10p in the supermarket, and clothes prices beat Primark hands down. The underground actually works (unlike London), and there are some great photos to be taken, particularly night shots while I’m recovering from my jet lag.

my attempt at night photography without a tripod

So, that’s what I think of Shanghai after about 3 days. Brilliant place, though a little crazy. If you want me to test some websites to see if they’re blocked, do comment / contact!

Software Swiss Army Knife

I’m leaving tomorrow for my epic journey into Communist China. Airports aren’t very laptop-friendly, what with the complicated rules on laptop cases and the possibility of breakage (knowing me…) and since I’ll be staying at a place which definitely has a computer, all I will be bringing is a single 1GB memory stick containing some of my most important school files in case my whole remote file access plan goes ‘fubar’, so to speak, owing to internet failure in some variant. I’m also operating under the assumption that this computer isn’t going to have the software I need, which means I’m going to need a swiss army knife of software. Apart from a MS Office 2007 CD and an emergency Sabayon Linux livecd, this is the software I’ll be bringing and I’d probably suggest this list as a must-have portable apps arsenal:

1. Tor: required for internet anonymity, it acts like a proxy and I’ll definitely be using it to get round China’s great firewall if and when necessary.
2. Firefox 3.1, complete with bookmarks and extensions etc: Essential, especially as torifying Firefox is unbelievably easy (and secure)
3. WinRAR (or 7-zip): Compressed files play a big part in online file transfers
4. Xerobank Browser: Basically Firefox with Tor built into it, complete with a few security-minded plugins.
5. Run.exe: A Communist country will have Communist administrators who lock down PCs and disable access to the run commands menu. I run half my software from there (Win+R > iexplore.exe rather than *click* > *click* > *double click* > *click* etc.) so an alternative is useful
6. Truecrypt: I encrypt a lot of stuff, and Truecrypt does it best.
7. Filezilla: Best FTP software I’ve ever used. I’ll be using FTP mostly for file transfers so it’ll definitely come in handy
8. VLC: It’s often known as the swiss army knife of media players. It will play anything and everything from .mp3 to .ogg to .mkv.

Meanwhile I’ve got a proxy set up on my server (for me only I’m afraid – don’t want to get blocked by school filters). Right then, I’m all prepped. See you all on the other side, and have a great Christmas!