Quantum error correction(QEC; Chinese: 量子纠错)(QEC)is a set of techniques in quantum information science designed to protect fragile quantum states from errors induced by environmental noise, decoherence, and imperfect quantum operations

The Livonian Order's contingent featured a small elite of heavy cavalry knights—estimated at 100 or fewer—equipped with chainmail hauberks, great helms, lances, swords, and large kite shields for shock charges on horseback. Modern scholarly assessments, including David Nicolle's analysis, place the number of Teutonic knights at approximately 100 within a total crusader force of around 2,600. These were augmented by Brüder (sergeant brothers) and Gebrochen (half-brothers) as mounted or dismounted infantry, alongside crossbowmen and spearmen. The majority of the force comprised local Estonian levies and Dorpat's secular troops, including lightly armed foot soldiers with axes, spears, and bows, suited for skirmishing but less effective against disciplined Rus' formations. Total strength is debated, with contemporary estimates ranging from 2,000 to 3,000 combatants, reflecting the Order's reliance on regional mobilization amid stretched resources from Prussian campaigns. Estonian historian Andres Adamson argues that the Order's brethren at Lake Peipus can only have come from the two nearest commanderies, Viljandi (Fellin) and Võnnu (Wenden): under the Order's statutes a full convent was a commander and twelve brethren, giving about 26 knight-brethren, which matches the Livonian Rhymed Chronicle's 20 killed and 6 captured. On this reading the Order contingent with retainers numbered around 200, and the whole Livonian force, with the bishop of Dorpat's vassals and Estonian levies, about 700–900. The twelve-brother convent was, however, an ideal rather than a fixed garrison size, and the Order was probably understrength after its losses at Saule in 1236.As background, Friedrich Benninghoven's study of the Sword Brethren estimates that the order had about 110–120 brethren in Livonia before its defeat at Saule in 1236, where roughly half fell, and that the Teutonic Order's Livonian branch later numbered a little over 180 brethren; individual campaigns typically involved a few dozen knight-brethren, often fewer than ten. He reckons the vassals and visiting crusaders available across the whole Livonian theatre at about 3,000–4,000 men. Supplying even a 3,000-man army required on the order of 140 packhorses for food alone, which is why modern scholars regard armies of the period as relatively small and treat chroniclers' round figures in the tens of thousands with caution.

“produziu uma adaptação em mangá da famosa série de espionagem dos anos 1960 The Man from U.N.C.L.E.”