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991.
992.
目的:对广西大瑶山野生绞股蓝茎、叶中的六种无机元素进行测定.方法:采用湿法消化法和原子吸收法进行研究.结果:广西大瑶山野生绞股蓝茎、叶中六种元素含量差异较大,叶中的含量明显高于茎中的含量,所测的六种元素的含量依次为:Ca〉Mg〉Fe〉Mn〉Zn〉Cu.结论:广西大瑶山野生绞股蓝六种无机元素的含量较为丰富,可以满足人体的需要,本研究为探讨无机元素与绞股蓝药理作用之间的关系提供了可靠的依据,为绞股蓝药物开发提供了方向. 相似文献
993.
Self-crosslinked gelatin-oxidized hyaluronic acid/ hydroxyapatite (GEL-OHA/HAp) composite bone substitute was successfully prepared with a novel in situ precipitation method without using any toxic chemical cross-linkers, and its characterizations, including elemental composition, surface morphology, crystallinity, and structure of crystalline phase, were carried out. In order to evaluate its corresponding performances, comparisons with glutaraldehyde crosslinked gelatin/hydroxyapatite (GEL-Glu/ HAp) composite were made in detail. The results indicate that nano-HAp crystallites are homogeneously dispersed in both GEL-OHA/HAp and GEL-Glu/HAp composites, and the HAp crystallites in the former take larger particle size than those in the latter. Mechanical property tests show the acceptable mechanical strength at high strain of GEL-OHA/HAp composite. Study of in vitro degradation and swelling demonstrate that the two composites have similar degradation rate and water absorption capability. By in vitro cell culture, it has been found out that the cells on the GEL-OHA/HAp composite show higher proliferative potential than the cells on the GEL-Glu/HAp composite. Compared with GEL-Glu/HAp composite, GEL-OHA/HAp composite provides an excellent strategy for preparation of non-toxic bone substitute with acceptable corresponding properties. 相似文献
994.
In this paper, the generalized inverse eigenvalue problem for the (P,Q)-conjugate matrices and the associated approximation problem are discussed by using generalized singular value decomposition (GSVD). Moreover, the least residual problem of the above generalized inverse eigenvalue problem is studied by using the canonical correlation decomposition (CCD). The solutions to these problems are derived. Some numerical examples are given to illustrate the main results. 相似文献
995.
Varieties of trusted computing products usually follow the mechanism of liner-style chain of trust according to the specifications of TCG. The distinct advantage is that the compatibility with the existing computing platform is preferable, while the shortcomings are obvious simultaneously. A new star-style trust model with the ability of data recovery is proposed in this paper. The model can enhance the hardware-based root of trust in platform measurement, reduce the loss of trust during transfer process, extend the border of trust flexibly, and have the ability of data backup and recovery. The security and reliability of system is much more improved. It is proved that the star-style trust model is much better than the liner-style trust model in trust transfer and boundary extending etc. using formal methods in this paper. We illuminate the design and implementation of a kind of trusted PDA acting on star-style trust model. 相似文献
996.
In uncertain data management, lineages are often used for probability computation of result tuples. However, most of existing works focus on tuple level lineage, which results in imprecise data derivation. Besides, correlations among attributes cannot be captured. In this paper, for base tuples with multiple uncertain attributes, we define attribute level annotation to annotate each attribute. Utilizing these annotations to generate lineages of result tuples can realize more precise derivation. Simultaneously, they can be used for dependency graph construction. Utilizing dependency graph, we can represent not only constraints on schemas but also correlations among attributes. Combining the dependency graph and attribute level lineage, we can correctly compute probabilities of result tuples and precisely derivate data. In experiments, comparing lineage on tuple level and attribute level, it shows that our method has advantages on derivation precision and storage cost. 相似文献
997.
A novel anonymous authentication scheme is proposed based on the ring signature. In the scheme, the private key and the the freely chosen anonymity set are used to achieve anonymous authentication. In terms of the threshold sharing, a group of t members jointly implement threshold tracking. In order to improve the security of tracking, message recovery equation is used to verify and recover data leaked by the user. Compared with Liu et al’s scheme, the proposed scheme can resist conspiracy tracking and has less computational cost. On the premise of the discrete-logarithm-based assumption put forth by Lysyanskaya, Rivest, Sahai, and Wolf (LRSW) and Diffie-Hellman (DDH) assumption, the scheme is proved to meet the demands of anonymous authentication. The scheme has broad application prospects in many fields such as ad hoc network, electronic voting, and so on. 相似文献
998.
This paper presents a systematic method of designing the calibration toolbox of automotive electronic control unit (ECU) based on real-time workshop (RTW). To break the strong coupling of each functional layer, the hierarchical architecture of the calibration system is divided into the bottom driver layer, the intermediate interface layer and the top application layer. The driver functions meeting the specification of the automotive open system are sent and received in the intermediate interface layer. To reduce the development costs, the portable user codes are generated by RTW which provides a development environment from system simulation to hardware implementation. Specifically, the calibration codes yielded from the controller area network (CAN) calibration protocol (CCP) module are integrated into the control codes, called by a compiler in the daemons to build a corresponding project, and then downloaded into the object board to provide the A2L file. The experiments illustrate that the different drive modules are only needed to be replaced for the implementation of the calibration system applied in different hardware platforms. 相似文献
999.
A class of singular perturbation boundary problem of elliptic equation for higher order is studied. Firstly, under suitable conditions, the generalized outer solution to reduced problems is considered. Then the generalized interior shock asymptotic solution to original problem is constructed by using the theory of generalized functions. Finally, using the fixed point theorem of functional analytic, the uniformly validity of the generalized asymptotic solution with interior shock and boundary layers is proved. 相似文献
1000.
The composite field multiplication is an important and complex module in symmetric cipher algorithms, and its realization performance directly restricts the processing speed of symmetric cipher algorithms. Based on the characteristics of composite field multiplication in symmetric cipher algorithms and the realization principle of its reconfigurable architectures, this paper describes the reconfigurable composite field multiplication over GF((2~8)~k)(k=1,2,3,4) in RISC(reduced instruction set computer) processor and VLIW(very long instruction word) processor architecture, respectively. Through configuration, the architectures can realize the composite field multiplication over GF(2~8), GF((2~8)~2), GF((2~8)~3) and GF((2~8)~4) flexibly and efficiently. We simulated the function of circuits and synthesized the reconfigurable design based on the 0.18 μm CMOS(complementary metal oxide semiconductor) standard cell library and the comparison with other same kind designs. The result shows that the reconfigurable design proposed in the paper can provide higher efficiency under the premise of flexibility. 相似文献