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21.
1 INTRODUCTIONSincethediscoveryoftheuniaxialNd2 Fe14 Bcompoundin 1983[1,2 ] ,theNdFeBalloyshavebeenwidelyusedforpermanentmagnetapplicationsowingtotheirexcellentmagneticproperties ,suchashighcoercivity ,high energy products[3,4 ] .Intheserareearthpermanentmagnets ,afurtherexcitingrecentdevelopmentisthesuggestionofnano compositeex changemagnetscombiningthelargecoercivitiesinhardmagnetswithlargeinductionsfoundinsoftertransitionmetalmagnets[5,6 ] .Indeed ,thenano com positemagnetshavebeent… 相似文献
22.
Timo Baur Rebecca Breu Tibor Kálmán Tobias Lindinger Anne Milbert Gevorg Poghosyan Helmut Reiser Mathilde Romberg 《Journal of Grid Computing》2009,7(3):319-333
In many Grid infrastructures different kinds of information services are in use, which utilize different incompatible data structures and interfaces to encode and provide their data. Homogeneous monitoring of these infrastructures with the monitoring data being accessible everywhere independently of the middleware which provided it, is the basis for a consistent status reporting on the Grids’ resources and services. Thus, interoperability or interoperation between the different information services in a heterogeneous Grid infrastructure is required. Monitoring data must contain the identity of the affected Virtual Organization (VO) so that it can be related to the resources and services the VO has allocated to enable VO-specific information provision. This paper describes a distributed architecture for an interoperable information service, which combines data unification and categorization with policies for VO membership, VO resource management and data transformations. This service builds the basis for an integrated and interoperating monitoring of Grids, which provide their data to more than one VO and utilize heterogeneous information services. 相似文献
23.
Maria Giretova Lubomir Medvecky Radoslava Stulajterova Tibor Sopcak Jaroslav Briancin Monika Tatarkova 《Journal of materials science. Materials in medicine》2016,27(12):181
Polyhydroxybutyrate/chitosan/calcium phosphate composites are interesting biomaterials for utilization in regenerative medicine and they may by applied in reconstruction of deeper subchondral defects. Insufficient informations were found in recent papers about the influence of lysozyme degradation of chitosan in calcium phosphate/chitosan based composites on in vitro cytotoxicity and proliferation activity of osteoblasts. The effect of enzymatic chitosan degradation on osteoblasts proliferation was studied on composite films in which the porosity of origin 3D scaffolds was eliminated and the surface texture was modified. The significantly enhanced proliferation activity with faster population growth of osteoblasts were found on enzymatically degraded biopolymer composite films with α-tricalcium phosphate and nanohydroxyapatite. No cytotoxicity of composite films prepared from lysozyme degraded scaffolds containing a large fraction of low molecular weight chitosans (LMWC), was revealed after 10 days of cultivation. Contrary to above in the higher cytotoxicity origin untreated nanohydroxyapatite films and porous composite scaffolds. The results showed that the synergistic effect of surface distribution, morphology of nanohydroxyapatite particles, microtopography and the presence of LMWC due to chitosan degradation in composite films were responsible for compensation of the cytotoxicity of nanohydroxyapatite composite films or porous composite scaffolds. 相似文献
24.
The cholinergic efferent inhibition of mammalian outer hair cells (OHCs) is mediated by a hyperpolarizing K+ current. We have made whole-cell tight-seal recordings from single OHCs isolated from the guinea pig cochlea to characterize the mechanism by which acetylcholine (ACh) activates K+ channels. After ACh application, OHCs exhibited a biphasic response: an early depolarizing current preceding the predominant hyperpolarizing K+ current. The current-voltage (I-V) relationship of the ACh-induced response displayed an N-shape, suggesting the involvement of Ca2+ influx. When whole-cell recording was combined with confocal calcium imaging, we simultaneously observed the ACh-induced K+ current (IK(ACh)) and a Ca2+ response restricted to the synaptic area of the cell. This IK(ACh) could be prevented by loading OHCs with 10 mM of the fast Ca2+ buffer bis(2-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid (or BAPTA), therefore allowing the observation of the ACh-induced early current in isolation. This early current revealed nicotinic features because it activated with an intrinsic delay in the millisecond range, reversed nearly in between potassium and sodium equilibrium potentials, and was blocked by curare. However, it was strongly reduced in the absence of external Ca2+, and its I-V relationship displayed an unusual outward rectification at positive membrane potentials and an inward rectification below -60 mV. The results indicate that the cholinergic response of mammalian OHCs involves a "nicotinic-like" nonspecific cation channel through which Ca2+ enters and triggers activation of nearby Ca2+-dependent K+ channels. 相似文献
25.
The model selection paradigm is one of the focused themes within decision science. This paper addresses the consistent solution of model selection issue on the basis of the fuzzy axiomatic design (FAD) methodology. Moreover, the developed FAD–based model selection interface (FAD–MSI) is performed over the critical ship management processes in order to assign suitable (multiple criteria decision-making) MCDM techniques even if commonly utilized hybrid approaches. The outcomes of this study encourage the maritime practitioners for the further researches towards analytical modelling of ship management processes. 相似文献
26.
Mao-Lin Ni Meng Joo Er 《Automatic Control, IEEE Transactions on》2001,46(3):509-511
A completed proof for a theorem on the robust controller design proposed in Wang and Ghosh (ibid. vol.43 (1997)) is presented in this paper 相似文献
27.
Viktor Sverdlov Tibor Grasser Hans Kosina Siegfried Selberherr 《Journal of Computational Electronics》2006,5(4):487-450
Transport in single and double barrier devices is studied using a Monte Carlo solver for the Wigner transport equation. This
approach allows the effects of tunneling and scattering to be included. Several numerical methods have been improved to render
the Wigner Monte Carlo technique more robust, including a newly developed particle annihilation algorithm. A self-consistent
iteration scheme with the Poisson equation was introduced. The role of scattering and space charge effects on the electrical
characteristics of n-i-n nanostructures, ultra-scaled double gate MOSFETs, and GaAs resonant tunneling diodes is demonstrated.
An erratum to this article can be found at 相似文献
28.
The logarithmic model is often used to describe the relationships between factors.It often gives good statistical characteristics.Yet,in the process of modeling of soil and water conservation,we find out that this“good”model cannot guarantee good result.In this paper we make an inquiry into the intrinsic reasons.It is shown that the logarithmic model has the property of enlarging or reducing model errors,and the disadvantages of the logarithmic model are analyzed. 相似文献
29.
在役混凝土桥梁结构可靠度评估的模糊类比法 总被引:1,自引:0,他引:1
分析影响混凝土桥梁结构可靠度的各种因素.对各种因素所起的作用进行分类.并建立各种影响因素之间的递阶层次关系,采用层次分析法确定各种因素影响结构可靠度大小的权重向量.最后采用模糊类比相似度的方法对在役桥梁结构可靠度进行评估。 相似文献
30.
陈二保 《安徽工业大学学报》2003,20(4):273-277
实验测定了不同温度时C在Mn-Fe熔体中的溶解度.Mn-Fe熔体从纯Fe到纯Mn的整个浓度范围内C溶解度计算式为XC=0.632 1e(-1413.6/T)-0.100 1XFe.通过热力学推导和计算,获得Mn基体系热力学性质与温度的关系式为1)Mn-C系,lg=-613.8/T-0.1992,Δ=26717-57.45 T( J/mol), ln= 3 213.5/T- 3.790 5, = 9 883/T+ 5.777 3, =222/T + 0.049 4; 2) Mn- Fe- C系, =582/T+ 0.020 4, =1 776/T+ 0.476 0 和 =8.313 4/T+ 0.001 8. 相似文献