Herein we would like to comment on the paper ＂Estimation of potential distribution of gas hydrate in the northern South China Sea＂ by Wang et al. 2010 in Chinese Journal of Oceanology and Lirnnology, 28（3）： 693-6...Herein we would like to comment on the paper ＂Estimation of potential distribution of gas hydrate in the northern South China Sea＂ by Wang et al. 2010 in Chinese Journal of Oceanology and Lirnnology, 28（3）： 693-699. The purpose of this comment is to point out that the given probabilities of gas hydrate occtwrence in the northern Zhujiang Mouth Basin and the Yinggehai Basin in the figure of Wang et al. （2010） are improper. After introducing our work of estimation of gas hydrate stability distribution in the northern South China Sea, we suggest that Wang et al. （2010） dismissed the basic P-T rule for the existence of gas hydrate. They should consider more the variables of water depth, seabed temperature and geothermal gradient in their gas hydrate distribution model in future studies.展开更多
Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable s...Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable songs and those that produce many song types. Estimating repertoire size is important for ecological and evolutionary studies of speciation, studies of sexual selection, as well as studies of how species may adapt their songs to various acoustic environments. There are several methods to estimate repertoire size, however prior studies discovered that all but a full numerical count of song types might have substantial inaccuracies associated with them. We evaluated a somewhat novel approach to estimate repertoire size--rarefaction; a technique ecologists use to measure species diversity on individual and population levels. Using the syllables within American robins＇ Turdus migratorius repertoire, we compared the most commonly used techniques of estimating repertoires to the results of a rarefaction analysis. American robins have elaborate and unique songs with few syllables shared between individuals, and there is no evidence that robins mimic their neighbors. Thus, they are an ideal system in which to compare techniques. We found that the rarefaction technique results resembled that of the numerical count, and were better than two alternative methods （behavioral accumulation curves, and capture-recapture） to estimate syllable repertoire size. Future estimates of repertoire size, particularly in vocally complex species, may benefit from using rarefaction techniques when numerical counts are unable to be performed [Current Zoology 57 （3）： 300-306, 2011].展开更多
This article is part exposition of a recent rather technical paper of the last two authors on matrix pavings related to the 1959 Kadison-Singer Extension Problem and part a report on further computational results prov...This article is part exposition of a recent rather technical paper of the last two authors on matrix pavings related to the 1959 Kadison-Singer Extension Problem and part a report on further computational results providing new bounds on the paving parameters for classes of small matrices investigated there and subsequently. A website maintained by the authors provides to all interested the matrices experimentally discovered that yield these bounds along with the proprietary MATLAB software with simple operational directions to load them, pave them, and perform paving searches. The convergence to 1 or not of the infinite sequences of these paving parameters in most cases is equivalent to the Kadison-Singer Extension Problem, and in all cases convergence to 1 negates the problem. The last two sections describe the search process and an interpretation of the data integrated with the results of the precursor to this paper.展开更多
基金Supported by the National Natural Science Foundation of China (No. 40774033)National Basic Research Program of China (973 Program) (No. 2009CB219503)the National High Technology Research and Development Program of China (863 Program) (No. 2006AA09A203-05)
文摘Herein we would like to comment on the paper ＂Estimation of potential distribution of gas hydrate in the northern South China Sea＂ by Wang et al. 2010 in Chinese Journal of Oceanology and Lirnnology, 28（3）： 693-699. The purpose of this comment is to point out that the given probabilities of gas hydrate occtwrence in the northern Zhujiang Mouth Basin and the Yinggehai Basin in the figure of Wang et al. （2010） are improper. After introducing our work of estimation of gas hydrate stability distribution in the northern South China Sea, we suggest that Wang et al. （2010） dismissed the basic P-T rule for the existence of gas hydrate. They should consider more the variables of water depth, seabed temperature and geothermal gradient in their gas hydrate distribution model in future studies.
文摘Song repertoire size is the number of distinct syllables, phrases, or song types produced by an individual or population. Repertoire size estimation is particularly difficult for species that produce highly variable songs and those that produce many song types. Estimating repertoire size is important for ecological and evolutionary studies of speciation, studies of sexual selection, as well as studies of how species may adapt their songs to various acoustic environments. There are several methods to estimate repertoire size, however prior studies discovered that all but a full numerical count of song types might have substantial inaccuracies associated with them. We evaluated a somewhat novel approach to estimate repertoire size--rarefaction; a technique ecologists use to measure species diversity on individual and population levels. Using the syllables within American robins＇ Turdus migratorius repertoire, we compared the most commonly used techniques of estimating repertoires to the results of a rarefaction analysis. American robins have elaborate and unique songs with few syllables shared between individuals, and there is no evidence that robins mimic their neighbors. Thus, they are an ideal system in which to compare techniques. We found that the rarefaction technique results resembled that of the numerical count, and were better than two alternative methods （behavioral accumulation curves, and capture-recapture） to estimate syllable repertoire size. Future estimates of repertoire size, particularly in vocally complex species, may benefit from using rarefaction techniques when numerical counts are unable to be performed [Current Zoology 57 （3）： 300-306, 2011].
基金supported by Naval Academy Research Council seed grants
文摘This article is part exposition of a recent rather technical paper of the last two authors on matrix pavings related to the 1959 Kadison-Singer Extension Problem and part a report on further computational results providing new bounds on the paving parameters for classes of small matrices investigated there and subsequently. A website maintained by the authors provides to all interested the matrices experimentally discovered that yield these bounds along with the proprietary MATLAB software with simple operational directions to load them, pave them, and perform paving searches. The convergence to 1 or not of the infinite sequences of these paving parameters in most cases is equivalent to the Kadison-Singer Extension Problem, and in all cases convergence to 1 negates the problem. The last two sections describe the search process and an interpretation of the data integrated with the results of the precursor to this paper.
