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The relationship between the Bayesian approach and the minimum description length approach is established. We sharpen and clarify the general modeling principles minimum description length (MDL) and minimum message length (MML), a...
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The relationship between the Bayesian approach and the minimum description length approach is established. We sharpen and clarify the general modeling principles minimum description length (MDL) and minimum message length (MML), abstracted as the ideal MDL principle and defined from Bayes's rule by means of Kolmogorov complexity. The basic condition under which the ideal principle should be applied is encapsulated as the fundamental inequality, which in broad terms states that the principle is valid when the data are random, relative to every contemplated hypothesis and also these hypotheses are random relative to the (universal) prior. The ideal principle states that the prior probability associated with the hypothesis should be given by the algorithmic universal probability, and the sum of the log universal probability of the model plus the log of the probability of the data given the model should be minimized. If we restrict the model class to finite sets then application of the ideal principle turns into Kolmogorov's minimal sufficient statistic. In general, we show that data compression is almost always the best strategy, both in model selection and prediction.
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Accurate determination of protein secondary structure from the chemical shift information is a key step for NMR tertiary structure determination. Relatively few work has been done on this subject. There needs to be a systematic in...
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Accurate determination of protein secondary structure from the chemical shift information is a key step for NMR tertiary structure determination. Relatively few work has been done on this subject. There needs to be a systematic investigation of algorithms that are (a) robust for large datasets; (b) easily extendable to (the dynamic) new databases; and (c) approaching to the limit of accuracy. We introduce new approaches using k-nearest neighbor algorithm to do the basic prediction and use the BCJR algorithm to smooth the predictions and combine different predictions from chemical shifts and based on sequence information only. Our new system, SUCCES, improves the accuracy of all existing methods on a large dataset of 805 proteins (at 86% Q3 accuracy and at 92.6% accuracy when the boundary residues are ignored), and it is easily extendable to any new dataset without requiring any new training. The software is publicly available at http://monod.uwaterloo.ca/nmr/succes.
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Noise complaints in New Zealand suggest that multi-family domestic buildings are not providing for the sound insulation needs associated with modern ways of living. We argue that verification measurements should be more widely enc...
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Noise complaints in New Zealand suggest that multi-family domestic buildings are not providing for the sound insulation needs associated with modern ways of living. We argue that verification measurements should be more widely encouraged. The research described is aimed at developing screening techniques which are convenient and easy to carry out. The approach is to reduce measurement effort by minimising the amount and weight of equipment needed. It is demonstrated that airborne measurements are possible without using a loudspeaker source - for example using a tapping machine on a "radiation" box. Also it is shown that impact insulation can, in principle, be predicted from airborne insulation measurements alone i.e. without the use of a tapping machine. This requires a library of 'corrections' factors. Values for some typical floor constructions and coverings are presented. Finally we demonstrate that a lightweight, single hammer, tapping machine can satisfactorily measure standardised impact sound pressure levels.
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This paper is an attempt to provide an explanation for the socioeconomic foundation which underlies China's economic miracle. As suggested by the theory of interlinked contract, the transition from a planning economy to a market e...
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This paper is an attempt to provide an explanation for the socioeconomic foundation which underlies China's economic miracle. As suggested by the theory of interlinked contract, the transition from a planning economy to a market economy is a multifaceted process. In terms of market dynamics interlinking markets replace specialized markets, while in terms of governance dynamics, interlinked contracts give way to formal contracts. A good match between the markets structure and contractual structure is key to the success of transition. In particular, some China-specific institutions, like TVEs, the financial system and the restructuring of SOEs can be better understood within this framework. Broadly, the whole reform package in China also is in good accordance with the spirit of interlinked contract.
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Existence of the optimal prefix codes is shown in this paper. Relationship between the optimal prefix code and the Huffman code is also discussed. We prove that all Huffman codes are optimal prefix codes and conversely optimal pre...
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Existence of the optimal prefix codes is shown in this paper. Relationship between the optimal prefix code and the Huffman code is also discussed. We prove that all Huffman codes are optimal prefix codes and conversely optimal prefix codes need not be Huffman codes. Especially, the problem of whether the optimal prefix code has to be maximal is presented. Although for information source alphabets of being not greater than four letters we show that an optimal prefix code must be maximal, it remains to be an open problem in general. As seen from Huffman codes, optimal prefix codes are used not only for statistical modeling but also for dictionary methods. Moreover, it is obtained that the complexity of breaking an optimal prefix code is NP-complete from the viewpoint of computational difficulty.
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The cross-bridge power-stroke model has been widely used to describe the motion of large motor assemblies
connected to a common rigid filament. In this paper, we go beyond the original velocity-ensemble approach
and propose a mast...
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The cross-bridge power-stroke model has been widely used to describe the motion of large motor assemblies
connected to a common rigid filament. In this paper, we go beyond the original velocity-ensemble approach
and propose a master equation approach to account for the cooperative motion of a finite number of motors
based on the cross-bridge model. By studying the force-velocity relationship for motors with strain-independent
detachment rate, we show the convergence of our approach to the velocity-ensemble approach in the limit of large
motor numbers. In the case that the detachment rate of motors is strain dependent, based on two assumptions
for the strain distribution among motors, we show the occurrence of the bimodal distribution of the number of
motors bound to the filament. This provides a new perspective to look at the instability of a multimotor system,
which is essential for all the experimentally observed complex motions displayed by a group of motors, such as
hysteresis, bidirectional motion, and spontaneous oscillation. By comparing the velocities calculated using the
two assumptions with the stochastic simulation, it suggests that the coupling between motors via the common
connection to the filament might facilitate the fast movement of filaments at small loading forces.
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Optimal spaced seeds were introduced by the theoretical computer science community to bioinformatics to effectively increase homology search sensitivity. These seeds are serving many homology queries daily. However the computation...
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Optimal spaced seeds were introduced by the theoretical computer science community to bioinformatics to effectively increase homology search sensitivity. These seeds are serving many homology queries daily. However the computational complexity of finding the optimal spaced seeds remains to be open. In this paper, we prove that computing hit probability of a spaced seed in a uniform homology region is NP-hard, but it admits a probabilistic PTAS. We also show that the asymptotic hit probability is computable in exponential time in seed length, independent of the homologous region length.
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Sputtering losses of zinc oxide films prepared by radical assisted sputtering were studied. It was found that the sputtering loss can be very severe in oxygenous sputtering processes of zinc oxide films. In general, resputtering c...
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Sputtering losses of zinc oxide films prepared by radical assisted sputtering were studied. It was found that the sputtering loss can be very severe in oxygenous sputtering processes of zinc oxide films. In general, resputtering caused by negative oxygen ions dominates the sputtering loss, while diffuse deposition plays a minor role. Resputtering is strongly correlated with the sputtering threshold energy of the deposited films and the concentration of O~ in the sputtering zone. The balance between the oxygen concentration in the sputtering zone and the oxidation degree of the growing films depends on the sputtering rate. Our research suggests that a lower oxygen concentration in the sputtering zone and a higher oxidation degree of the growing films are favorable for reducing the resputtering losses. The sputtering loss mechanisms discussed in this work are also helpful for understanding the deposition processes of other magnetron sputtering systems.
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The recursive least squares (RLS) algorithms is a popular parameter estimation one. Its consistency has received much attention in the identification literature. This paper analyzes convergence of the RLS algorithms for controlled...
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The recursive least squares (RLS) algorithms is a popular parameter estimation one. Its consistency has received much attention in the identification literature. This paper analyzes convergence of the RLS algorithms for controlled auto-regression models (CAR models), and gives the convergence theorems of the parameter estimation by the RLS algorithms, and derives the conditions that the parameter estimates consistently converge to the true parameters under noise time-varying variance and unbounded condition number. This relaxes the assumptions that the noise variance is constant and that high-order moments are existent. Finally, the proposed algorithms are tested with two example systems, including an experimental water-level system.
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As a special breed in Asia, yellow-feather broilers have high nutrition and can deteriorate easily under chilled conditions. The present work evaluated the effect of different storage temperatures (−2, 1 and 4C) on the shelf life...
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As a special breed in Asia, yellow-feather broilers have high nutrition and can deteriorate easily under chilled conditions. The present work evaluated the effect of different storage temperatures (−2, 1 and 4C) on the shelf life of chilled yellowfeather chicken under modified atmosphere packaging (CO2/N2: 80%/20%). The total viable counts reached the limit value (7.0 log colony-forming unit [cfu]/g) after 28 and 12 days of storage at 1 and 4C, whereas it did not exceed 7.0 log cfu/g during the whole −2C storage period. The samples stored at −2C had the lowest total volatile basic nitrogen content and maintained the best sensory quality and lowest drip loss among the three groups. The shelf lives of samples stored at −2 and 1C were significantly extended for 16 days compared with traditional chilling at 4C. Our results provide practical information on shelf life extension of chilled yellow-feather broiler meat, which provide benefits to the industry to reduce unnecessary food waste.
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