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81.
To extend two previous surveys of specific decision support system (DSS) applications over the period (January 1971–December 1994), we have conducted a follow-up survey covering the period between 1995 and 2001. A total of 210 published applications are identified. To examine the development pattern of a specific DSS over time, we analysed and summarized the survey results according to (1) the area of application, (2) the year of publication in each area of application, (3) the distribution of underlying tools in DSSs, (4) a classification based on Alter's taxonomy, and (5) the management level (operational, tactical, or strategic) for which the DSS was designed. 相似文献
82.
Breast milk contains human milk oligosaccharides (HMOs), including sialyllactose (SL). SL is composed of sialic acid and lactose, and is divided into 3′-SL and 6′-SL according to the binding position. SL has immunoprotective effects against bacteria and viruses, and acts as a probiotic in the gastrointestinal tract. In this study, we developed a bioanalytical method for simultaneous analysis of 3′-SL and 6′-SL in liver and kidney tissues of Yucatan minipigs using liquid chromatography–tandem mass spectrometry (LC-MS/MS) under conditions optimized in our previous study. LC-MS/MS was performed using a hydrophilic interaction liquid chromatography (HILIC) column (50 mm × 2.1 mm, 3 μm) with a mobile phase consisting of 10 mM ammonium acetate in water (pH 4.5) and acetonitrile with gradient elution at a flow rate of 0.3 mL/min. A surrogate matrix method using water was applied for analysis of endogenous SL. The developed method was validated with regard to selectivity, linearity, precision, accuracy, the matrix effect, recovery, parallelism, dilution integrity, carryover, and stability according to the US Food and Drug Administration guidelines. We performed a tissue distribution study of minipigs, and analyzed liver and kidney tissues using the developed method to determine the tissue distribution of 3′-SL and 6′-SL. The tissue concentrations of 3′-SL and 6′-SL were readily measurable, suggesting that the method would be useful for evaluating the tissue distributions of these compounds in minipigs. 相似文献
83.
A MAC(Media Access Control) protocol, one of the most important technologies for an EPON(Ethernet Passive Optical Network), contains a scheduling algorithm to avoid collisions in shared links and assigns an effective bandwidth when ONUs (Optical Network Units) transfer signals upward. The current paper proposes a MAC Protocol that operates a TDMA(Time method with a variable slot assignment to overcome short of bandwidth using by the number of n wavelength., the next generation access network. To verify the above, the current study also implements an EPON model using OPNET as the simulation tool. 相似文献
84.
We have investigated the effects of electron density discontinuity on the transports of edge currents of two-dimensional electron gas (2DEG). The electric field applied to a gate, which covers the 2DEG partially, gives rise to change in the carrier density and results in a density gradient, which deforms the edge currents. The transverse and longitudinal resistances were measured as functions of gate voltage VG in the quantum Hall regime. The deviations of the longitudinal resistances from the normal quantum Hall resistances are attributed to the reflections of the edge currents under the influence of the abrupt density discontinuity. A switching behavior of the transverse resistance by controlling the gate voltage was observed when VG=−2.2 and −2.0 V for magnetic field H=5 and 7.2 T, respectively. 相似文献
85.
Dikin DA Mehta M Bark CW Folkman CM Eom CB Chandrasekhar V 《Physical review letters》2011,107(5):056802
Ferromagnetism is usually considered to be incompatible with conventional superconductivity, as it destroys the singlet correlations responsible for the pairing interaction. Superconductivity and ferromagnetism are known to coexist in only a few bulk rare-earth materials. Here we report evidence for their coexistence in a two-dimensional system: the interface between two bulk insulators, LaAlO(3) (LAO) and SrTiO(3) (STO), a system that has been studied intensively recently. Magnetoresistance, Hall, and electric-field dependence measurements suggest that there are two distinct bands of charge carriers that contribute to the interface conductivity. The sensitivity of properties of the interface to an electric field makes this a fascinating system for the study of the interplay between superconductivity and magnetism. 相似文献
86.
The magnetic properties and the Griffiths singularity were investigated in Mn-site doped manganites of La0.45Sr0.55Mn1−xCoxO3 (x=0, 0.05, 0.10 and 0.15) in this work. The parent sample La0.45Sr0.55MnO3 undergoes a paramagnetic-ferromagnetic transition at TC=290 K and a ferromagnetic-antiferromagnetic transition at TN=191 K. The doping of Co ions enhances the ferromagnetism and suppresses the antiferromagnetism. The enhanced ferromagnetism results from the fact that the Co doping enhances the Mn3+-Mn4+ double-exchange interaction and induces the Co2+-Mn4+ ferromagnetic superexchange interaction. Detailed investigation on the magnetic behavior above TC exhibits that the Griffiths singularity takes place in this series of Mn-site doped compounds. The correlated disorder induced by the Co ionic doping, together with the phase competition from the ferromagnetic and the antiferromagnetic interactions among Mn ions, is responsible for the Griffiths singularity. 相似文献
87.
Jae‐Eun Park Jae‐Hoon Eom Taehoon Lim Do‐Hoon Hwang Seungmoon Pyo 《Journal of polymer science. Part A, Polymer chemistry》2012,50(11):2188-2193
In this study, organic memory devices with a single active layer between the two external electrodes were fabricated using an electron‐donor type conjugated polymer and an electron‐acceptor type small organic molecule. The active layer of the memory device was prepared by blending polystyrene, poly[10‐(2′‐ethylhexyl)phenothiazine‐3,7‐diyl], and tetracyanoquinodimethane in 1,2‐dichlorobenzene. The device initially showed a low‐conductance state (OFF state) in the low‐voltage range, and an abrupt current increase, corresponding to the transition to a high‐conductance state (ON state), occurred at a certain voltage (Vth). The ON state could be reverted to the OFF state by applying a voltage higher than Vth. The current ratio between the two states was about 103 (up to 105). After this transition, the device remained in the ON state even after the applied voltage was removed, and this indicated the nonvolatile characteristics of the device. There was no sharp current degradation in the OFF or ON states for 4500 s of continuous bias. The device‐to‐device performance fluctuation was measured, and the conduction mechanisms in the ON and OFF states were examined by fitting the data to well‐known theoretical models. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
88.
A simple way to make the closed forms stiffness matrix of macro triangle elements is proposed through the individual element test and the computational algebra system in this paper. The newly developed element consists of three constant strain triangles, which only satisfy the convergence conditions according to the individual element test. Computational algebra system MAPLE and the free formulation framework are used to combine the stiffness matrix with the free parameters in terms of the algebraic symbols. The assembly of three constant strain triangles produces the linear strain modes in the resulted macro elements. The rigid body modes and constant strain modes of elements and the newly produced linear strain modes of the macro element are systematically assembled in the basic stiffness and the higher order stiffness in the free formulation procedure. The parameter of the decomposed higher order stiffness was tuned through the bending test. The results of numerical examples show the advantages of the proposed macro element in the distorted mesh and elements with the high aspect ratio. 相似文献
89.
The thermal degradation behavior of crystalline cellulose has been investigated using thermogravimetry, differential thermal analysis, and derivative thermogravimetry in a nitrogen atmosphere. Three cellulose samples, Halocynthia, cotton, and commercial microcrystalline cellulose Funacel, were used in this study to analyze the influence on crystallite size. They all belongs to cellulose Iβ type and those crystallite sizes calculated from the X-ray diffractometry profiles by Scherrer equation were very different in the order Halocynthia > cotton > Funacel. The thermal decomposition of cellulose shifted to higher temperatures with increasing crystallite size. However, activation energies for the thermal degradation were the almost the same among the samples: 159-166 kJ mol−1. These results indicated that the crystal structure does not affect the activation energy of the thermal degradation but the crystallite size affects the thermal degradation temperature. 相似文献
90.
We propose and demonstrate a novel modal delay measurement technique for a higher-order mode fiber (HOF) based on optical frequency-domain reflectometry (OFDR) using an extremely simple, entirely passive, and ultrafast wavelength sweeping mechanism, namely, dispersion-induced optical pulse stretching. We obtained a high temporal resolution of approximately 1.12 ps, which was sufficient for discerning the four excited modes in an HOF with a length of only approximately 5 m. The results from our measurements were very consistent with those obtained by using a traditional time-domain measurement method and a conventional OFDR measurement based on a tunable CW laser. Our proposed technique can be also easily adapted to perform conventional time-domain modal delay measurements for very long HOFs. 相似文献