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A graph is k-choosable if it can be colored whenever every vertex has alist of available colors of size at least k. It is a generalization of graphcoloring where all vertices do not have the same available colors. Weshow that ever...
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A graph is k-choosable if it can be colored whenever every vertex has alist of available colors of size at least k. It is a generalization of graphcoloring where all vertices do not have the same available colors. Weshow that every triangle-free plane graph without 6-, 7-, and 8-cycles is3-choosable.
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Whenever the Z machine is fired, the building that houses the pulsed-power scientists at Sandia National Laboratories in Albuquerque, New Mexico, rumbles. Some of the scientists have taken to measuring the building movement with t...
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Whenever the Z machine is fired, the building that houses the pulsed-power scientists at Sandia National Laboratories in Albuquerque, New Mexico, rumbles. Some of the scientists have taken to measuring the building movement with the accelerometers on their laptops. Before each shot, a few hundred thousand gallons of insulating transformer oil are drained -so that the donut-shaped tank can be checked for damage-and then poured back; divers also check a central 6-meter-deep tank of deionized water to rid it of bubbles, which could potentially damage the machine by concentrating electric fields.
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You may not know it, but machine learning is all around you. When you type a query into a search engine, it's how the engine figures out which results to show you-and which ads. When you read your email, you don't see most of the ...
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You may not know it, but machine learning is all around you. When you type a query into a search engine, it's how the engine figures out which results to show you-and which ads. When you read your email, you don't see most of the spam because machine learning has filtered it out. Go to Amazon to buy a book or Netflix to watch a video, and a machine-learning system helpfully recommends some others you might like. Facebook uses machine learning to decide which updates to show you, and Twitter does the same for tweets. Whenever you use a computer, chances are machine learning is involved somewhere.
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Currently my Pringles tube-cum-Enigma machine sits proudly on the kitchen worktop, ready for whenever I need to encrypt a top-secret message ... or eat a savoury snack. You can make your own paper Enigma at http://tinyurl.com/Your...
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Currently my Pringles tube-cum-Enigma machine sits proudly on the kitchen worktop, ready for whenever I need to encrypt a top-secret message ... or eat a savoury snack. You can make your own paper Enigma at http://tinyurl.com/Your-Enigma. Thank you to Tom for delivering an entertaining workshop at the Maths Scholars Celebratory Event. I thought the day couldn't get any better, but naturally I was proven wrong, as a free lunch had just started being served.
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In their letter [1], Steiger and Muller propose a definition ofindividual recognition (IR) that differs from the definitionused in our review [2]. The difference between our defi-nition of IR and the definition proposed by Steiger...
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In their letter [1], Steiger and Muller propose a definition ofindividual recognition (IR) that differs from the definitionused in our review [2]. The difference between our defi-nition of IR and the definition proposed by Steiger andMuller [1] can be highlighted using Sherman et al.'s [3]recognition framework. Sherman et al. [3] suggest thatrecognition involves (i) cue production by the signaller,(ii) cue perception and template matching by the receiverand (iii) a behavioural response by the receiver. We [2]defined IR as occurring when cue, template and responseare all individual specific. Steiger and Muller [1] posit thatIR occurs whenever the cue and the template are individ-ual specific. In contrast to our view, they suggest thatindividual-specific receiver responses are not a require-ment for IR.
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摘要 :
In their letter [1], Steiger and Muller propose a definition ofindividual recognition (IR) that differs from the definitionused in our review [2]. The difference between our defi-nition of IR and the definition proposed by Steiger...
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In their letter [1], Steiger and Muller propose a definition ofindividual recognition (IR) that differs from the definitionused in our review [2]. The difference between our defi-nition of IR and the definition proposed by Steiger andMuller [1] can be highlighted using Sherman et al.'s [3]recognition framework. Sherman et al. [3] suggest thatrecognition involves (i) cue production by the signaller,(ii) cue perception and template matching by the receiverand (iii) a behavioural response by the receiver. We [2]defined IR as occurring when cue, template and responseare all individual specific. Steiger and Muller [1] posit thatIR occurs whenever the cue and the template are individ-ual specific. In contrast to our view, they suggest thatindividual-specific receiver responses are not a require-ment for IR.
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Information professionals and their commercial partners have been longterm collaborators. We share an interest in improving access for our user communities, and we also share a drive to expand the diverse information ecologies we ...
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Information professionals and their commercial partners have been longterm collaborators. We share an interest in improving access for our user communities, and we also share a drive to expand the diverse information ecologies we oversee. There is a widespread consensus that we benefit whenever we pool our collective wisdom to help our users navigate information landscapes. By working together, we can smooth the way for those users to discover the electronic resources they need with less pain.
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Whst's Special: Mars is always a welcome sight in the night sky whenever it's on-show. It's seen close to its best much less often than fellow superior planets (those that orbit the Sun at a distance greater than Earth) Jupiter an...
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Whst's Special: Mars is always a welcome sight in the night sky whenever it's on-show. It's seen close to its best much less often than fellow superior planets (those that orbit the Sun at a distance greater than Earth) Jupiter and Saturn, owing to its mean synodic period of 780 days, which means it comes to opposition only in alternate years. Mars is therefore much cherished during an opposition year, as is the case in 2022, especially when it is making a real impact, as it does this month.
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The CD spectra of 13 crystalline aryl benzyl sulfoxides la—m with various substituents on the twoaromatic rings were recorded in solution and in the solid state. Solution CD spectra were veryhomogeneous along the series, consisti...
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The CD spectra of 13 crystalline aryl benzyl sulfoxides la—m with various substituents on the twoaromatic rings were recorded in solution and in the solid state. Solution CD spectra were veryhomogeneous along the series, consisting in most cases of a couplet-like feature in the 200-300 nmregion. The red-shifted component of the couplet. corresponding to the sulfoxide-centered nay*transition, is always positive for ( R) absolute configuration in accordance with Mislow's rule. Thepresence of a strong electron-withdrawing substituent on the phenyl ring (nitro or ester group) altersthe shape of the CD spectrum. CD calculations using the TDDFT method were run for eightrepresentative compounds using DFT-optimized geometries. In all cases, calculated spectra were invery good agreement with experimental ones and allowed for rationalization of the diverse spectralbehaviors. It is demonstrated that TDDFT//DFT calculations represent a reliable option for assigningthe absolute configuration of this class of compounds whenever crystals suitable for X-ray are notavailable. Solid-state CD spectra recorded with the KCI pellet technique were in some cases inagreement with those in solution. However, in other cases new and strong CD signals appeared whichwere interpreted as being due to intermolecular couplings in the crystals.
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