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1.
2.
Beyond the Web: Mobile WAP-Based Management 总被引:1,自引:0,他引:1
Luca Deri 《Journal of Network and Systems Management》2001,9(1):15-29
Mobility, tightening competition and changes in system administrator behavior present new challenges in the management world. In particular, the need to constantly monitor services and rapidly identify and fix problems is becoming increasingly important. The Internet has made it possible to offer a comprehensive range of management services and applications accessible over the web. Nevertheless, in the near future a new and improved way to manage systems will be done by means of mobile phones. This paper shows how existing web-based solutions can be enhanced to support the new generation of media phones based on WAP (Wireless Application Protocol) technology. Although the specific focus of this work is on management solutions, the rsults are general and applicable to many other types of existing web-based applications. Some implementation details and experiences drawn from adding a WAP interface to an existing web-based management application are described. 相似文献
3.
Deri R.J. Yasuoka N. Makiuchi M. Hamaguchi H. Wada O. Kuramata A. Hawkins R.J. 《Photonics Technology Letters, IEEE》1990,2(7):496-498
An integrated waveguide-photodiode with an external quantum efficiency as high as 56% (coupled to single-mode fiber) and large bandwidth (5.5-11.2 GHz) at 1.55-μm wavelength is described. This performance was achieved utilizing a vertical impedance matching design for improved guide-detector coupling 相似文献
4.
类Kerr媒质中双光子J-C模型场的压缩效应 总被引:8,自引:2,他引:6
研究类Kerr媒质中双光子J-C模型腔场的压缩效应,揭示类Kerr媒质对光场压缩 的影响. 相似文献
5.
Rudolf K. Zahn Gertrud Zahn-Daimler W.E.G. Müller Martin L. Michaelis Branko Kurelec Marija Rijavec Renato Batel Nevenka Bihari 《The Science of the total environment》1983,26(2):137-156
The sponge Tethya lyncurium from the Northern Adriatic has been used as an experimental species.A method is outlined for preparation of DNA which yields a highly purified DNA with a double-strand (ds) molecular weight of 25 M-dalton between single-strand (ss) breaks, which when properly damaged can be cut opposite to ss-breaks with nuclease s1. The molecular weights of the resulting ds-DNA pieces and their distribution has been evaluated by electron microscope photographs.Sponges exposed to benzo[a]pyrene (BaP) in the dark only incorporate BaP-derivatives (BaPD) in small amounts, if any. However, in the presence of light, derivatization to BaP derivatives enables effective coupling to occur, as shown previously (R. K. Zahn et al., 1981). Sponges were exposed to radiolabeled BaP in the presence of light. Coupling of BaPD to the DNA as well as the induction of ss-breaks were measured.Light-mediated coupling is concentration dependent from 0.01 – 20 ppb BaP with a correlation coefficient of r = 0.84.Under conditions of possible repair, ss-breaks completely disappear from sponge DNA in the course of three weeks while a substantial fraction of the BaP derivatives persists.Double label experiments show that substantial DNA synthesis occurs during this time. Pollution causes a decrease of the molecular weight of unnicked DNA, re-incubation in clean water an increase. A DNA species of 24 M-dalton seems to play a critical role. If its percentage in the DNA population drops below a critical level, recovery is not longer possible. DNA damage by PAH and repair in sponges seems to differ from that of most eucaryotes. 相似文献
6.
V Qui?ones-Jenab P Batel SD Schlussman A Ho MJ Kreek 《Canadian Metallurgical Quarterly》1997,58(4):1009-1013
The present study investigated the onset of maternal nest building in pregnant Fischer rats following chronic repeated cocaine administration. Pregnant Fischer rats were injected with saline or cocaine, 15 mg/kg, three times daily at 1-h intervals for 10 days starting on gestation day 8. Cocaine-exposed females incorporated less material into their nests and built fewer fully completed circular nests than control animals. The overall quality of the nest in cocaine exposed dams was significantly lower than that of control animals. Furthermore, cocaine exposed dams gained less weight than control females. However, no difference in number of pups, weight, or length of pups was observed between groups. Thus, it seems that cocaine disrupts the interest and skill in nest building of pregnant rats. 相似文献
7.
Laser diode to single-mode fiber ball lens coupling efficiency: full-wave calculation and measurements 总被引:1,自引:0,他引:1
We show that the coupling efficiency from a laser diode (LD) to an optical fiber through a ball lens can be calculated accurately using the exact solution to Maxwell's equations for the scattering of a beam from a dielectric sphere. Our calculated results agree closely with coupling measurements from an asymmetric LD for two different ball lenses. 相似文献
8.
Studies have been made on the dynamic oscillation and static properties in the molten state of blends from polybutene-1 and polypropene. Measurements were made with a balance-rheometer system Dr. Kepes and a capillary viscosimeter. Three experimental parameters, η0, τ0 and h have been determined. Steady shear and oscillatory shear viscosity data have been compared. A plot of intrinsic viscosity vs. composition of blends shows a minimum. Variation of η0 and τ0 with temperature follow the Arrhenius law but h does not depend on temperature. 相似文献
9.
D Tesi? M Deri? T Ivkovi?-Lazar P Pantelinac L Lepsanovi? 《Canadian Metallurgical Quarterly》1996,49(7-8):313-317
One of the characteristics of peripheral vascular disease in diabetic patients is that it occurs at the time of detection of diabetes mellitus. As one of the possible pathogenic mechanisms, in non-smokers, is the sol-called metabolic syndrome (obesity, disorders in regard to metabolism of lipids and carbohydrates and hypertension). Lipoprotein Lp(a) is the most atherogenic among lipoproteins. While data on coronary arterial disease exist, although contradictory, there is a small number of those which document the same for peripheral vascular occlusive disease in diabetics. Two patients, non-smokers, with characteristic constellation of risk factors, are described as possible models for further epidemiologic examinations. 相似文献
10.
Rheological and mechanical properties of poly(lactic acid)/polystyrene polymer blend 总被引:2,自引:0,他引:2
Properties modification by blending polymers has been an area of immense interest. In this work, rheological and mechanical
properties of poly(lactic acid)/polystyrene (PLA/PS) blends were investigated. PLA/PS blends in different ratios were prepared
using a laboratory scale single screw extruder to obtain (3 mm) granules. Rheological properties were studied using a capillary
rheometer and the Bagley’s correction was performed. True shear rate (γ
r
), true shear stress (τ
r
), and true viscosity (η
r
) were determined, the relationship between true viscosity and (1/T) was studied for PLA70 blend and the flow activation energy at a constant shear stress (E
τ
) and a constant shear rate (E
γ
) was determined. The mechanical property measurements were performed at room temperature. Stress at break and strain at break
were determined. The results showed that PLA/PS blend exhibited a typical shear-thinning behavior over the range of the studied
shear rates, and the viscosity of the blend decreased with increasing PLA content. Also it was found that no equal-viscosity
temperature exists between PLA and PS. The mechanical results showed immiscibility between PLA and PS in the blend. 相似文献