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951.
Won Sang Chung Taekyun Kim Hyuck In Kwon 《Russian Journal of Mathematical Physics》2014,21(2):156-168
In this paper, we consider the q-analog of the Laplace transform and investigate some properties of the q-Laplace transform. In our investigation, we derive some interesting formulas related to the q-Laplace transform. 相似文献
952.
Beom-Seok Lee Bo-Yun Kim Ji-Hyeon Lee Jong Hee Yoo Kwon Hong Sahn Nahm 《Current Applied Physics》2014,14(12):1825-1830
Pt/TiO2/TiN device with the amorphous TiO2 film grown at room temperature under an oxygen partial pressure of 1.0 mTorr showed reliable bipolar switching behavior. During the electroforming process, a large number of oxygen vacancies formed in the TiO2 film and accumulated at the Pt/TiO2 interface. The barrier height of the Schottky contact of the Pt/TiO2 interface was reduced owing to the presence of these oxygen vacancies, resulting in the low-resistance state (LRS). Moreover, oxygen ions diffused into the TiN electrode during the electroforming and set processes. On the other hand, the oxygen ions in the TiN electrode diffused out and reacted with oxygen vacancies in the TiO2 film during the reset process, and the device changed from the LRS to the high-resistance state (HRS). Conduction in the LRS and HRS can be attributed to Ohmic conduction and the trap controlled space charged limited mechanism, respectively. 相似文献
953.
We report on the aerosol synthesis and optical characterization of ZnO/unoxidized graphene (UG) platelets nanocomposite films with high optical transparency (>85% at visible wavelengths). The ZnO/UG composite films, in which UG nanoplatelets are embedded in nano‐grained ZnO, were fabricated from colloidal suspensions of UG platelets with an aqueous zinc precursor. From photoluminescence (PL) spectra of the UG composite films, it was found that PL intensity decreases with the addition of UG platelets. The features of PL intensity in the UG composites are in contrast to that of ZnO/graphene oxide (G‐O) platelets composites, and can be explained by the absence of an oxygen vacancy filling effect, due to the unoxidized nature of UG and an increase in defect sites in its composites. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献
954.
In this paper, we study the optimal policies of retailers who operate their inventory with a single period model (i.e., newsvendor model) under a free shipping offer where a fixed shipping fee is exempted if an order quantity is greater than or equal to a given minimum quantity. Zhou et al. (2009) have explored this model, and we further investigate their analysis for the optimal ordering policies which they did not sufficiently develop. Based on the investigation, we extend the base model in order to deal with the practically important aspect of inventory management when the exact distribution function of demand is not available. We incorporate the aspect into the base model and present the optimal policies for the extended model with a numerical example. Finally, we conduct extensive numerical experiments to evaluate the performance of the extended model and analyze the impacts of minimum free shipping quantity and the fixed shipping fee on the performance. 相似文献
955.
We study one-step extensions of 2-variable weighted shifts. We provide necessary and sufficient conditions for the subnormality of such extensions, by using backward extensions, disintegration of measures, and k-hyponormality techniques from the theory of 2-variable weighted shifts. We apply our results to solve an interpolation problem for measures on ${\mathbb{R}_+^2}$ . 相似文献
956.
Jie Chen Hoon Wei Lim San Ling Huaxiong Wang Hoeteck Wee 《Designs, Codes and Cryptography》2014,73(3):911-947
We present efficient identity-based encryption (IBE) under the symmetric external Diffie–Hellman (SXDH) assumption in bilinear groups; our scheme also achieves anonymity. In our IBE scheme, all parameters have constant numbers of group elements, and are shorter than those of previous constructions based on decisional linear (DLIN) assumption. Our construction uses both dual system encryption (Waters, CRYPTO 2009) and dual pairing vector spaces (Okamoto and Takashima, Pairing 2008; ASIACRYPT 2009). Specifically, we show how to adapt the recent DLIN-based instantiation of Lewko (EUROCRYPT 2012) to the SXDH assumption. To our knowledge, this is the first work to instantiate either dual system encryption or dual pairing vector spaces under the SXDH assumption. Furthermore, our work could be extended to many other functional encryption. In Particular, we show how to instantiate our framework to inner product encryption and key-policy functional encryption. All parameters of our constructions are shorter than those of DLIN-based constructions. 相似文献
957.
We study the fractional Schrödinger equations in R1+d, d?3, of order d/(d−1)<α<2. Under the angular regularity assumption we prove linear and nonlinear profile decompositions which extend the previous results [9] to data without radial assumption. As applications we show blowup phenomena of solutions to mass-critical fractional Hartree equations. 相似文献
958.
On the unit ball of ? n , the space of those holomorphic functions satisfying mean Lipschitz condition $$ \int_0^1 \omega^*_p(t, f)^q \frac{dt}{t^{1+ q}} <\infty$$ is characterized by integral growth conditions of the tangential derivatives as well as the radial derivatives, where \(\omega^*_p(t, f)\) denotes the double difference L p modulus of continuity defined in terms of the unitary transformations of ? n . 相似文献
959.
Kim SH Kwon SW Chu SY Lee JH Narsaiah B Kim CH Kang SK Kang NS Rhee SD Bae MA Ahn SH Ha DC Kim KY Ahn JH 《Chemical & pharmaceutical bulletin》2011,59(1):46-52
In the continuation of our 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) inhibitor research, cyclic sulfonamide derivatives with an acetamide group at the 2-position were synthesized and evaluated for their abilities to inhibit 11β-HSD1. Among this series, Compound 34 showed good in vitro activity toward human 11β-HSD1, selectivity against 11β-HSD2, microsomal stability, good pharmacokinetic and safety profiles human ether-a-go-go related gene (hERG and cytochrome P450 (CYP)). Also, a docking study explained the activity difference between human and mouse 11β-HSD1. 相似文献
960.
Khiev P Oh SR Chae HS Kwon OK Ahn KS Chin YW Lee HK 《Chemical & pharmaceutical bulletin》2011,59(3):382-384
Bioactivity-guided isolation on a n-hexane-soluble fraction of Thyrsanthera suborbicularis led to the isolation of a new rosane-type diterpene, 19-hydroxy-1(10), 15-rosadiene (1), along with three known compounds, taraxerol, acetyl aleuritolic acid, and spathulenol. The structures of isolated compounds were determined by interpretation of NMR spectroscopic data and mass spectrometry. Compound 1 demonstrated significantly inhibitory activity on nitric oxide production in RAW264.7 lipopolysaccharide (LPS)-activated mouse macrophages with an IC(50) value of 2.91 μg/ml via the suppression of inducible nitric oxide synthase (iNOS) mRNA expression. 相似文献