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71.
In this study, we show that earnings forecasting creates an index-tracking portfolio that dominates the historical model trade-off curve. We find that using Toyo Keizai earnings forecasts improves geometric means by over 300 basis points compared to the historical model. Weighted latent root regression is used in this study to create portfolios that have outperformed the Japanese market in backtest and in real-time performance. 相似文献
72.
Kuno A. Zheng G. D. Matsuo M. Takano B. Shi J. A. Wang Q. 《Hyperfine Interactions》2002,141(1-4):321-326
In this study, 57Fe Mössbauer spectroscopy has been applied to sediments collected from Qinghai Lake in Qinghai Province, China, to investigate the vertical distribution of iron species. Their Mössbauer spectra consisted of four doublets ascribable to one paramagnetic high-spin Fe3+, two paramagnetic high-spin Fe2+ with different quadrupole splittings, and one diamagnetic low-spin Fe2+ that corresponds to pyrite (FeS2). The distribution of pyrite suggested climatic changes during the past nine thousand years. It was demonstrated that the iron speciation in the salt lake sediments by Mössbauer spectroscopy can be used to reconstruct the past environment.
相似文献73.
74.
Hiroshi Kageyama Takashi Watanabe Yoshihiro Tsujimoto Atsushi Kitada Yuji Sumida Kazuyoshi Kanamori Kazuyoshi Yoshimura Naoaki Hayashi Shigetoshi Muranaka Mikio Takano Monica Ceretti Werner Paulus Clemens Ritter Gilles Andr 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2008,120(31):5824-5829
75.
2-(2-Dithianyl)benzhydrols ( a-c) undergo facile cycloaddition reaction with maleic anhydride under thermal conditions to give 1-phenyl-naphthalenes ( a-c) in one step. The naphthalenes ( a-c) have been converted into the naphthalene lignan lactones, ( a-c) and ( a-c). 相似文献
76.
Annals of the Institute of Statistical Mathematics - In Part I the Khintchine’s uniqueness theorem for the class convergence of probability distributions is proved in a natural way by making... 相似文献
77.
Yuji Yaegashi Seiji Adachi Takahiro Wada Satoshi Takano H. Yamauchi 《Physica C: Superconductivity and its Applications》1992,190(4):433-436
Yb(Ba1−xSrx)2Cu4O8 (0.1x0.3) superconductors of the YBa2Cu4O8(“124”) structure were successfully synthesized using an O2-hot-isostaticc-pressing (HIP) technique. The samples were characterized with respect to the crystal structure and superconducting properties. The lattice parameters of the samples decreased as the substitution of Sr for Ba proceeded. The superconducting transition temperatures of all the Yb-“124” samples were more or less the same, being around 80 K. 相似文献
78.
In order to obtain clear scintigrams of small animals, some improvements were brought on a pinhole collimator. Then, using a human gamma camera with this collimator improved, bone scintigraphy was attempted in the rat mandible and maxilla, experimentally to examine the desirable conditions of scintigraphy. The most desirable bone scan images were obtained under the conditions that the pinhole was 1.5 mm in diameter, the distance between the collimator and the object was 0 cm, and the exposure was 400. 相似文献
79.
Homoorientaline 4 was oxidised with homogenised potato peelings along, followed by acetylation, to give 1-hydroxyhomoorientaline triacetate 9, the structure of which was determined by spectroscopic data and an alternative synthesis. 相似文献
80.
Seiji Takano 《Journal of multivariate analysis》1973,3(1):93-101
The problem of multivariate information analysis is considered. First, the interaction information in each dimension is defined analogously according to McGill [4] and then applied to Markov chains. The property of interaction information zero deeply relates to a certain class of weakly dependent random variables. For homogeneous, recurrent Markov chains with m states, m ≥ n ≥3, the zero criterion of n-dimensional interaction information is achieved only by (n ? 2)-dependent Markov chains, which are generated by some nilpotent matrices. Further for Gaussian Markov chains, it gives the decomposition rule of the variables into mutually correlated subchains. 相似文献