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751.
752.
To deal with the robust portfolio selection problem where only partial information on the exit time distribution and on the conditional distribution of portfolio return is available, we extend the worst-case VaR approach and formulate the corresponding problems as semi-definite programs. Moreover, we present some numerical results with real market data. 相似文献
753.
754.
Thatiparti Thimma Reddy Michiko Hadano Atsushi Takahara 《Macromolecular Symposia》2006,242(1):241-249
Segmented polyurethane ureas (SPUUs), which are being used in implant devices, were evaluated as drug delivery matrices using theophylline as a model drug without much sacrificing the mechanical properties of films after drug doping. SPUUs were synthesized from aliphatic diisocyanate (lysine methyl ester diisocyante (LDI)), poly(caprolactone) diol with molecular weights 530, 1250 and 2000 and 1,4-butanediamine. Three series of segmented SPUUs were prepared with various soft segment lengths and were characterized by Fourier transform infrared spectroscopy, dynamic viscoelastic measurements and tensile testing. A single tanδ peak was observed in dynamic viscoelastic measurements, which revealed phase mixing of hard and soft segments. Low elongation at break was observed in case of PCL 2000 based SPUUs, may be due to partial cystallization of PCL segment. The degradation of SPUUs in alkaline solution and in vitro drug release of theophylline in pH 7.4 buffer were also investigated. The drug release behavior from these films were analyzed by the exponent relation Mt/M∞ = ktn, where k and n are constants and Mt/M∞ is the fraction of drug released until time, t. The constant n was found to be close to 0.5 in all samples, which suggests the release of drug from these polymers can be explained by the Fickian diffusion model. 相似文献
755.
Matsumoto K Narazaki M Ikehira H Anzai K Ikota N 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2007,187(1):155-162
The resolution and signal to noise ratio of EPR imaging and T(1)-weighted MRI were compared using an identical phantom. Several solutions of nitroxyl contrast agents with different EPR spectral shapes were tested. The feasibility of T(1)-weighted MRI to detect nitroxyl contrast agents was described. T(1)-weighted MRI can detect nitroxyl contrast agents with a complicated EPR spectrum easier and quicker; however, T(1)-weighted MRI has less quantitative ability especially for lipophilic nitroxyl contrast agents, because T(1)-relaxivity, i.e. accessibility to water, is affected by the hydrophilic/hydrophobic micro-environment of a nitroxyl contrast agent. The less quantitative ability of T(1)-weighted MRI may not be a disadvantage of redox imaging, which obtains reduction rate of a nitroxyl contrast. Therefore, T(1)-weighted MRI has a great advantage to check the pharmacokinetics of newly modified and/or designed nitroxyl contrast agents. 相似文献
756.
Kitagawa Michiko Ishida Nana Yoshino Erika Matsuhashi Hiromi 《Research on Chemical Intermediates》2020,46(7):3703-3715
Research on Chemical Intermediates - To obtain highly active solid base catalyst of magnesium oxide (MgO) under atmospheric conditions, hydroxide (Mg(OH)2), basic carbonate... 相似文献
757.
μSR spectra on the spin frustrating spinel antiferromagnet Zn(Cr
x
Ga1−x
)2O4 (x=0.9,1.0) have been measured. For x=1.0 compound, both the relaxation rate and the initial asymmetry showed distinct anomalies at the Néel temperature. The magnetic
susceptibility for the x=0.9 compound was known to have a faint peak at around 12 K, whose origin was not clear so far. Our μSR study revealed that
this temperature is the onset temperature of development of the magnetic correlation accompanied by appreciable spin fluctuations.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
758.
Mangasarian and Solodov have recently introduced an unconstrained optimization problem whose global minima are solutions of the nonlinear complementarity problem (NCP). In this paper, we show that, if the mapping involved in NCP has a positive-definite Jacobian, then any stationary point of the optimization problem actually solves NCP. We also discuss a descent method for solving the unconstrained optimization problem.The authors are indebted to a referee for a helpful suggestion that led them to develop the descent method described in Section 3. They are grateful to Professor F. Facchinei, who kindly pointed out an error in the proof of Theorem 2.3 in an earlier version of the paper. The also thank Professor P. Tseng for a discussion on Theorem 3.1. 相似文献
759.
Ushida N Kondo T Tasaka S Park IG Song JS Hara T Homma Y Tsuzuki Y Fujioka G Fukushima H Takahashi Y Tatsumi S Yokoyama C Fujiwara K Taruma K Bahk SY Kim CO Park JN Bailey DC Conetti S Mercure P Trischuk J Turcotte M Aoki S Chiba K Fuchi H Hoshino K Kodama K Matsui R Miyanishi M Nakamura M Nakazawa K Niu K Niwa K Ohashi M Sasaki H Tomita Y Torii N Yamakawa O Yanagisawa Y Aubrecht GJ Dunlea J Errede S Gauthier A Gutzwiller MJ Kuramata S Oleynik G Reay NW Reibel K Sidwell RA Stanton NR Moriyama K 《Physical review letters》1986,56(17):1767-1770
760.
Ono M Masuoka C Koto M Tateishi M Komatsu H Kobayashi H Igoshi K Ito Y Okawa M Nohara T 《Chemical & pharmaceutical bulletin》2002,50(10):1416-1417
A new ortho-benzoyloxyphenyl acetic acid ester, called vaccihein A (1), was isolated from the fruit of rabbiteye blueberry (Vaccinium ashei). The chemical structure was determined on the basis of spectroscopic data. Compound 1 had antioxidative activity using the ferric thiocyanate method. In addition, 1 showed a scavenging effect on the stable free radical 1,1-diphenyl-2-picrylhydrazyl. 相似文献