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Greenland, Euro and Wing Efficiency; A voice from my past


leong

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I’ve always wondered about the relative efficiency of the three main paddle types (Greenland, Euro and Wing). My old race-training partner from last century, Dr. Sanjay Gulati, once ran some tests; I recently found the results and put them in the table below (he published an article about this in a 2002 issue of Atlantic Coastal Kayaker). Sanjay paddled with each type of paddle to achieve a consistent heart rate for several minutes and recorded the speed results. He used a GPS to measure his speed and his heart monitor as a stand-in for level of effort (how hard is body was working).

Paddle Type Heart Rate Speed (knots) Subjective
Wing 115 5.0 moderate
Standard 115 4.7 easy
Greenland 115 4.7 very easy
Wing 140 5.7 hard
Standard 140 5.4 hard
Greenland 140 5.4 hard

According to the chart, Sanjay found that for a given level of effort (as measured by heart rate), and for moderately high speeds (4.7 knots to 5.4 knots), you get about 0.3 knots more speed with the wing paddle. That’s about a 5% speed increase. That’s consistent with what Olympic medallist Greg Barton said; i.e. wing paddles increase performance by 3% to 5% compared to Euro-paddles.

In my own experience, for an all-out-sprint with my wing paddle, my speed seems to increase by about 1% to 2% (compared to my flat Euro-paddle). Of course, your results will vary according to your level of fitness, distance to be paddled and quality of your forward stroke with each paddle type. And there are other variables to consider such as blade size, shaft length and hand placement on the paddle shaft. In fact, I don’t know if my wing improves my times in a long distance race such as the Blackburn Challenge (20 miles) or the NYC Mayor’s Cup (29 miles). But I use the wing because, 1. everyone else does and 2. I have no evidence to the contrary that the wing is the fastest.

My guess is that for slower speeds the GP paddle has the highest efficiency (where by higher efficiency I mean less effort to paddle at a given speed). Perhaps at some increased speed the Euro-paddle is the most efficient and at even higher speeds the wing is the most efficient. But this relationship may not scale up as distance increases (at least for ordinary mortals). But for the Oscar Chalupsky’s in the kayaking world the wing is probably fastest at all distances.

-Leon

PS

Some caveats to Sanjay’s study:

While paddling, the level of your effort and your resultant heart rate has a complicated relationship. When you paddle hard, your heart rate goes up. When you get tired, you find it harder to produce the same amount of power, and when you’re tired enough, you find it hard to raise your heart rate. And, all else being equal, the fitter you are, the more power you can produce at the same heart rate. So heart rate is not a very accurate way to measure your relative level of effort.

I don’t think there is a practical way to accurately measure a kayaker’s level of effort. An accurate measure is done in a laboratory with continuous samples of exhaled air being captured for analysis. The amount of carbon dioxide in each sample is related to level of effort. A person’s maximum level of effort corresponds to VO2max (the amount of oxygen your body is capable of utilizing in one minute).

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Thanks Leon. I'm not surprised at the Greenland stats. I find the GP easier to maintain maximum heart rate for a longer period of time which has always been interesting to me. Less strain on the upper body as well but that is my personal take on it.

Even though the wing can create more force, you have some limitation in alternate stroke finesse, do you agree? I have witnessed people slowing down in "conditions" using a wing which I have suspicion is due to losing efficiency by not being able to maintain proper form due to the need to add sweep strokes for example, decreasing a wings proficiency. To me, that seams to give a typical euro blade an advantage.

This is a loaded topic of discussion. I'm sure I will add more feedback later.

Doug

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Doug, I completely agree with you. I think the only advantage of the wing paddle is that you can eke out slightly greater speeds using one. The wing is definitely much less versatile than a standard Euro or a GP. For me, at least, the wing is particularly bad for draw strokes, sculling and high braces. My roll is not as bombproof with the wing either. The wing blade angle needs to be just right to prevent diving when doing a sweep roll.

The only reason I use my wing outside of racing is for the practice aspect. My guess is that for ultra long distances the wing may be less efficient than a GP or flat Euro paddle. But it may be the most efficient for long distance super stars like Freya.

I’ve watched you paddle using both a Euro paddle and a GP. You handle both like a violin virtuoso. That counts a lot more than any small increase in speed that you may get with a wing paddle.

Perhaps I’ll start using a GP when I get the racing bug out of my system. It was sure kind to my joints the few times I tried one.

By the way, most of the literature argues that there are the two main reasons why wing paddles are better for speed than Euro paddles (less slippage and better use of core muscles). Although somewhat correct, I don’t think they get to the heart of the matter. If fact, within limits, you can always reduce slippage with a Euro paddle by choosing a bigger blade and you can paddle correctly with it to use your core muscles as much as you want to. The following is what I think is the inherent advantage of wing paddles:

For a proper forward stroke both Euro and wing blades should move along a diagonal path relative to the boat (the Euro blade paddler follows the diagonal path for ergonomics; eg. to employ core rotation muscles). So, in both cases, there is a diagonal velocity vector (with respect to the boat) which is the sum of the backward velocity and the sideway velocity. For a Euro paddle, the sideway velocity doesn’t directly provide any forward thrust. For a wing paddle, because it’s designed to produce lift forces, the blade’s sideway velocity produces forward thrust. Thus if a wing and Euro paddle would follow identical diagonal paths the “effective” powered length of the stroke is longer with the wing blade than it is for the Euro blade. And longer stroke length results in greater speed.

-Leon

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Thanks for the generous compliment Leon but I must admit I often find myself getting lazy, especially with the euro blade and my efficiency suffers as a result. I enjoy watching people that maintain consistency and ponder on those with exaggerated form weighing weather or not they are at an advantage.

Doug

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I have read that the wing produces extra efficiency at the beginning of the stroke. The speed of the paddle movement at the diagonal from the bow of the boat produces the "lift" needed to lock the paddle in one place relative to the water so the paddler can pull the boat past. As the paddle moves out from the boat the angle changes subtly and you get more conventional rearward resistance. This was from a sprint site, though. They were moving that paddle really, really fast.

If you want that extra power from the paddle you have to move it explosively during the first fraction of a second. Feels like a situp in the core muscles.

One other advantage of the wing is a complete lack of flutter, no matter how you use it.

Even though the wing can create more force, you have some limitation in alternate stroke finesse, do you agree? I have witnessed people slowing down in "conditions" using a wing which I have suspicion is due to losing efficiency by not being able to maintain proper form due to the need to add sweep strokes for example, decreasing a wings proficiency.

Yes, but it probably also depends on what you're used to. Wing strokes for direction, balance and bracing look more like normal forward strokes. The wing is very supportive - every stroke is a brace - so that's what you rely on to keep the colored side up in conditions. Also, to maintain direction efficiently most racers use a rudder.

That being said, it's not the tool I would choose for quick maneuvers around rocks or in surf. That wants a different style of both paddle and boat. Not to mention training :-)

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There are a couple coupled issues here that I’ve become quite interested in:

Let’s start with the concept of work. It is defined as force times distance. So let’s consider a kayak that moves 1m forward during a stroke, and a paddle which because of slippage, moves 2 m backwards during that same time. (I know, bad paddle.) So the amount of work the paddler does during the stroke is F (force being applied to the paddle) x 2m. During that same time, the work done propelling the boat is F x 1m.

So the paddler uses 2F (units of force are nt-m or ft-lbs). 1F goes into propelling the boat and the other 1F goes into water turbulence and such, associated with paddle slippage. Clearly, the more paddle slippage occurs during a stroke, less of the paddler’s energy is being applied to forward motion.

So now let’s get a huge paddle that might slip only 10 cm during a stroke, and we get 1*F/(1.1*F) or ~90% paddle efficiency, clearly belter than the 50% with the hugely-slipping blade.

So why don’t we all use zero-slippage blades? 100% efficient, right? Well, that has to do with a concept called impedance, or roughly, how hard a paddle is to pull against. Our hugely-slipping paddle from the first example most likely doesn’t offer much resistance to the paddler, and is ‘easy’ to paddle. The paddle with less slippage might feel harder , or it ‘impedes’ us more as we try to pull against it.

My arms (in particular elbow tendons) have a definite impedance preference. Starting with too large a blade early in the season is a good way to head into tendinitis. So this would suggest that a maximum blade size derives from the paddlers conditioning and indeed, I found that kinesiology is very much concerned about load impedances on various athletic ventures. That’s the reason why blades over, say 750 cm^2 are generally not available to the general public.

So far, I’ve ignored blade shape and the concept of lift. One (simple) way to look at it is to try to minimize the amount of disturbance the blade leaves in the water. Recall that 50% efficient blade and think of all the churning it must have left in the water, compared to the 90% efficient one. Half of paddler’s energy went into the water by churning and eddy-making.

The idea behind a wing blade is to minimize the amount of residual vorticity in the water by generating lift instead of drag. As I look at my paddle stroke, I notice that my Ikelos leaves behind two prominent vortices (whirlpools) at each stroke. (In hydrodynamics, those are called a leading and tailing vortex.) My stellar wing only leaves behind ONE vortex, the tailing vortex. This post is likely not the place for a thorough explanation of why, but the wing blade increases efficiency by leaving less vorticity in the water by providing lift in addition to drag as it moves through the water.

Phew; this got a little longer than I’d intended it to, and I’d be glad to continue the discussion. I’ve recently become involved in paddle design from a kinesiological standpoint and am quite amazed by the sophistication of methods used to optimize paddlers for specific athletes. There’s a lot of very interesint hydrodynamics involved in the process.

Finally, I've been astounded at the Greenland paddle's ability to generate lift with a very small size. It seems the paddler has an option to adjust impedances over a wide range by slightly modifying their stroke. I find this absolutely fascinating and need to spend much more time with one on the water.

Edited by josko
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So the paddler uses 2F (units of force are nt-m or ft-lbs). 1F goes into propelling the boat and the other 1F goes into water turbulence and such, associated with paddle slippage. Clearly, the more paddle slippage occurs during a stroke, less of the paddler’s energy is being applied to forward motion.

Yes, but when you consider body mechanics and water drag the problem gets more complicated. Although any slippage results in less hydrodynamic efficiency, it also increases the speed of the paddle with respect to your body. In general, your body can produce more power with rapid low force movements rather than with slow high force movements. If we factor in body efficiency, we might find that net efficiency increases with a blade that slips a little because it results in higher speed body movements. Also, since drag forces in the water square with velocity, doubling the speed of the paddle increases the thrust to move the boat by a factor of four. That’s why you can paddle a boat pretty fast even with a very skinny blade. In other words, a higher cadence due to slippage may be more efficient for your body.

Lisa’s reference to wings being able to lock the paddle in place at the beginning of the stroke is more about world class sprinters than for most of us reading this forum. Those sprinters can generate very large forces and don’t worry about the body mechanics I that I mentioned above.

-Leon

PS

Although everything said is correct about why a wing allows you to paddle faster, I think they’re all minor compared to the fact that a wing increases the “effective” powered length of the stroke.

Edited by leong
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As most people in the club know, I have been using the wing paddle for many years but for different reasons than the manly-men in the club (that's a joke - not being disrespectful) . I paddle mostly with men and it does give me some umph over long distances when I need to keep up and not be a girlie-girl (rumor has it that is what Freya calls paddlers she has to wait for). The wing does help people like me - slight and small - in relatively calm waters.

However, I have found the wing has some serious if not dangerous drawbacks in conditions for paddlers like me. I think in his previous post Doug was referring to me losing it when we paddle in conditions. If so, alas, I do have my tale of woe.

Based on my experiences, the wing does have serious limitations in conditions. When I asked Oscar about the drawbacks of paddling a wing in strong winds, his response was he did not know what I was talking about. He wouldn't given his size, strength and weight.

If winds are 25 knots, more or less, beam or otherwise, the wing paddle acts as a propeller in my hands. It does not matter if I hold it low or high, I get this propeller effect. Every time I lift it out the water, it starts to twist and turn as the strong winds get caught on its curved edges and lifts it up. When this happens, I am not not only trying to control the boat but also the paddle that acts like it just took a hit of meth or pcp. Plus, I lack traction because of the weird angles produced by the wind. I am surprised that Doug has not taken a video of my swearing and slapping the water with my paddle during these conditions. I must be a sight of chaos.

Consequently, my boat gets pushed by wind and waves in multiple directions all at once. Even when I load my boat down with rocks in bow and stern I can still have this nightmare experience. The result is if I try really, really hard I basically stay in the same place. That is, if I am lucky. If I am not so lucky, which is most of the time, I get pushed back, make no headway and I end up dangerously close to crashing waves on rocks.

One recent paddle while using my wing, the conditions were such that the waves and current pushed my boat beyond my control (surprise, right?). My boat was pushed to a point where the bow was perpendicular to the wave crest. With no traction from the wing, my boat was forced into an "L" shape position. Imagine that my body is the line on the bottom of the "L"shape, if you will. The bow and cockpit were clear out of the water and I was being pushed back on to the rocks.

But I was lucky enough to be paddling with Bob Levine who towed me some distances just so I could make headway. If I was paddling with less experienced paddlers or by myself, I would of been in serious trouble.

Humbling to say the least.

Les

Edited by Lbeale
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As most people in the club know, I have been using the wing paddle for many years but for different reasons than the manly-men in the club (that's a joke - not being disrespectful) . I paddle mostly with men and it does give me some umph over long distances when I need to keep up and not be a girlie-girl (rumor has it that is what Freya calls paddlers she has to wait for). The wing does help people like me - slight and small - in relatively calm waters.

Hmm, Dear Les, you sure weren’t paddlin’ girlie-girl those times that I couldn’t keep up. For instance

-Leon

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Hmm, Dear Les, you sure weren’t paddlin’ girlie-girl those times that I couldn’t keep up. For instance

-Leon

PS

Speaking good wing, today (Monday, January 26, 2015) was my first combat capsize in a few years. I was heading back to enter the canal in Florida where my kayak lives. It was a very windy day (Wind direction: WSW 23 knots; Wind gust: 30 knots with high frequency chop in the bay).

I had been trolling in the bay and then put down my wing paddle to tie down my fishing rod when I suddenly went over. Failed the first attempted roll and came up successfully on the second attempt (used Pawlata both times). When I came up I almost crashed into the sea wall adjacent to the canal.

I took a few pictures and video of the choppy bay after I docked my kayak. A few other pictures were taken earlier from the lee side of Peanut Island, FL (looking east towards the ocean through Palm Beach inlet). I’ll leave the pictures and video here for about a month.

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If winds are 25 knots, more or less, beam or otherwise, the wing paddle acts as a propeller in my hands. It does not matter if I hold it low or high, I get this propeller effect. Every time I lift it out the water, it starts to twist and turn as the strong winds get caught on its curved edges and lifts it up.

While I like my wonderfully light-weight Epic carbon-fiber euro paddle (not a wing) in calm conditions, I hate how the wind grabs that paddle. When I first started carrying both my carbon-fiber euro and my much heavier cedar Greenland, I pretty much only used the Greenland paddle when I was rolling, afraid of hitting rocks with my paddle, or it was very windy.

Once I learned the Greenland sliding stroke I switched to using the Greenland paddle whenever conditions made boat control challenging, and whenever the water was shallow. Basically the sliding stroke provides extended-paddle sweep strokes which are wonderful for directional control. Especially once I realized that I could fully extend on one side of the kayak while only partly extending on the other side. I usually like a pretty vertical stroke, but using the sliding stroke and keeping the Greenland paddle low also further improves resistance to gusting winds. I'm sure the shape of the Greenland paddle helps with the wind. I suspect the heavier weight of my wooden Greenland paddles might also help a bit.

If you have a Greenland paddle with you, try it the next time you are swearing at the wind.

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With advance apologies for thread drift, could someone explain the concept and purpose of 'twist' in a wing blade. I took a lesson from Wesley Echols and got to try a range of blades, from untwisted, more forgiving paddles such as Stellar mid-wing to some high-twist paddles he races with. In general, I found higher-twist blades much more finicky, prone to stall and more demanding of all stroke aspects. Presumably, these demands are paid of by higher levels of performance, but I couldn't quite fathom the associated hydrodynamics.

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Josco,

The exact hydrodynamics are above my pay grade. Although you’ve probably viewed this elementary video that explains twist, it may be of interest to others.

-Leon

Edited by leong
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Josco,

To increase my knowledge on the subject I read a few scholarly articles about the hydrodynamics of wing paddles. A few points from two of the simpler articles follow:

This article LIFTING PERFORMANCE IN AQUATIC SPORTS
says about twist:

“More recent blades, such as the ‘Norwegian’ wing which superseded the Swedish wing, are literally a ‘wing with a twist’ (Figure 4). According to anecdotal evidence, the twist allows a ‘cleaner exit’, that is, it is easier for the paddler to withdraw the blade at the end of the stroke with minimal forces counter to the desired direction of travel.”

According to the article Hydrodynamics of Paddle Propulsion the theoretical speed advantage of a wing is 4%. But in practice this advantage must be reduced by other effects such as viscosity of water. Also [my two cents] this advantage assumes an optimal paddle stroke. But someone with a non-optimal euro paddle stroke may get a better improvement with a wing paddle because it tends to force a better stroke.

I’ve been experimenting with my wing stroke lately. I’ve found that increasing the initial velocity angle relative to the hull and its speed seems to increase my hull speed; i.e. I initially sweep out wider and faster than normally to increase the initial lifting thrust at the expense of the drag thrust. This seems to be consistent with some of the formulas and data in the article above. In fact, you can get more thrust from lift forces than from drag forces. I played around standing in shallow water and swept my wing paddle quickly out to the side. The amount of lifting force was really impressive. It depends a lot on the angle of attack (blade angle relative to sweep angle).

-Leon who’s still a novice on this subject

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Leon, that second link's (for me) a gold mine! Thank you!

While we're at it, I've learned (the hard way) that I need to start the season with a small blade and work up to a larger one, Otherwise elbow tendons seem to pay the price. I've also noticed that blade size seems to correlate with athlete's ability. Has anybody found an explanation of why a higher blade is more demanding of the athlete's body , and how to set up an off-season workout program to work one's way up to larger blades?

Edited by josko
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Josko:

My favorite paddle is the Lendal Storm, a 650 cm2 blade, 640 grams weight, 215 cm. Since I was interested in finding out what a larger blade would do for me in lumpy water, I purchased a Werner Corryvreckan 210 cm, a 721 cm2 blade weighing 800 grams. I paddled it for a day with the same focus on proper technique and...hated it. I felt like I was not making any headway. I did not feel that the blade was in any way harder to pull, it just felt that it was less efficient than the Storm. Interestingly, when I told John Carmody this, he felt the same way about the Corry (don't quote me, I believe that's what he said). Of course, the Corry and the Storm are very different in design but what I am trying to say is that blade-size per se may not be the only factor. This is a very personal observation (which was apparently confirmed by one of my betters) that is specific to 2 specific blades. I am aware of the more general issue of blade size and will incorporate this in the choice of the wing blade I pan to purchase next (Epic Mid Wing). I tried a Mid Wing in fall and loved it. While I'm on the subject of Epic mid Wing, does anyone have input on whether to get the burgundy or stiffer blue shaft. I'm aware of the theoretical differences, but does anyone have practical input ? Seems like the stiffer blue on is more durable, according to Epic's website. Input would be appreciated.

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FWIW, I use an Ikelos and Cyprus. In mid season, I find I can average 4.5 kts with the Ikelos over an 18 nmi course (around Naushon island) vs 4.3 with the Cyprus. There's no doubt in my mind that for me, Ikelos is a more efficient blade once I'm fit enough to take advantage of it.

I tried out the Stellar mid-wing two years ago, and I couldn't get past the 4.5 knot avg on that course. I ran across some surf skiers, and one of them mentioned I was spinning it out and should try a larger blade. So now I'm wondering how to select my next wing blade. It seems to all be about conditioning and cadence.

Edited by josko
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Andy, go with the burgundy Epic mid-wing, not the blue shaft.

Doug

Yes, definitely. The stiff shaft (the blue one) is only appropriate for sprints. You'll do a job on your joints using the blue shaft for distance paddling (unless you're Rambo and can bench-press over 300 lbs.)

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I think it meant my cadence was too high as the blade wasn't offering appropriate impedance., i.e. it was too small.

Josco,

You can lower your cadence by a stronger blade lock (the blade doesn’t move backwards with respect to the water). I’ve had good results doing this by exaggerating the sideways movement of the wing at the initial pull after the catch. I’m not sure whether the experts recognize this as good practice. Anyway, take a look at some of the tips from the experts here and here.

.

Note how the athletes use their legs to improve the forward stroke (it’s clearly shown in the slow motion section of the second video). Obviously, when you are taking a forward stroke on the right (left) side of your kayak, you should be pushing against the right (left) foot brace with your right (left) foot. The opposite makes no sense from a bio-mechanical point of view. This topic was beat to death here.

Incidentally, the very first time I saw Ms. Huntington she was paddling a recreational kayak and I noticed her excellent leg action. That was the tell that made me realize that she had great potential as a kayak racer. And with a little coaching and a lot a practice it came to pass.

-Leon

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My apologies, we had discussed the Corry and I like it but I really do think the blade needs to match the boat. I only use the Corry with my fastest sea kayak, it does not feel right with my Aquanaut HV.

Then again since I liked my first paddle, a 240cm Lendal Nordkapp (old model, bigger blades) I may be a numbskull who would be happy paddling anything.

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A little off topic but …

Look at the slow motion section of this video showing Knut Holmann (three Olympic Golds) paddling. Notice how soon and how far that he sweeps the blade out to the side.

It looks like he starts the action slightly before the blade is fully buried. I guess he doesn’t follow the Brent Reitz rule for the catch; i.e. “If you start to unwind AS you plant the blade, rather than before the blade is fully buried beneath the surface, you will unnecessarily lose several inches in the stroke length and lose a lot of power stored up in your rotation. These inches can add up to as much as an 18% loss in efficiency over the course of a race."

Also, he doesn’t follow the “chicken wing” rule.

I suppose that when you’re as good as Knut you don’t have to follow all rules to the letter to get the gold.

-Leon

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How would I decide between the Epic Mid Wing or the Epic Mid large Wing. Only data point I have is that I was spinning out the Stellar mid wing, which at 755 cm^2, is just 5 cm^2 larger than the Epic mid wing. Also, Archee lent me his Epic mid-large briefly, and it didn't seem overwhelming, but I didn't use it long enough to get a meaningful workout. My target use for this paddle would be the 18 nautical mile Naushon circumnavigation in the P&H Bahiya with the goal of averaging faster than 4.5 knots.

I know an obvious answer is to paddle both, but to me, that would make sense in mid-season, when I'm fit enough to handle my usual blade.

Edited by josko
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