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151.
152.
Network management in large heterogeneous communication environments requires the incorporation of more advanced tools than are currently available, especially in the area of fault management. By providing an informational infrastructure for documenting network behavior and maintenance activities, TTSs (trouble ticket systems) have provided some relief for the fault management problem. Researchers have recognized TTSs as a means for realizing more advanced functions in network management platforms to effect automatic trouble ticket generation, fault diagnostics, and the correlation of multiple views network problems and behavior. The authors describe current research trends towards understanding and implementing these advanced functions in a TTS framework 相似文献
153.
154.
Metal-Resistance-Semiconductor (MRS) photodetectors are characterized by a resistive layer placed in series to an avalanching region. In this paper, we report the characterization of such devices, we define a parameter extraction procedure, and we derive a quantitative model of the MRS operation. Due to the presence of the ohmic layer, the detector works as an ensemble of pixels with separately stabilized operating bias. In this way, compared to avalanche photodiodes (APDs), MRS achieve superior gain uniformity with the same sensitive area. However, there are still aspects of the fabrication technology and of the detector structure which have to be improved 相似文献
155.
Harame D.L. Comfort J.H. Cressler J.D. Crabbe E.F. Sun J.Y.-C. Meyerson B.S. Tice T. 《Electron Devices, IEEE Transactions on》1995,42(3):455-468
A detailed review of SiGe epitaxial base technology is presented, which chronicles the progression of research from materials deposition through device and integration demonstrations, culminating in the first SiGe integrated circuit application. In part I of this paper, the requirements and processes for high-quality SiGe film preparation are discussed, with emphasis on fundamental principles. A detailed overview of SiGe HBT device design and implications for circuit applications is then presented 相似文献
156.
Ferdinand P. Ferragu O. Lechien J.L. Lescop B. Magne S. Marty V. Rougeault S. Kotrotsios G. Neuman V. Depeursinge Y. Michel J.B. Van Uffelen M. Varelas D. Berthou H. Pierre G. Renouf C. Jarret B. Verbandt Y. Stevens W. Voet M.R.H. Toscano D. 《Lightwave Technology, Journal of》1995,13(7):1303-1313
Recent developments of stability control in mines, essentially based on Ge-doped fiber Bragg gratings (FBG) are reported including results about the different aspects of the system: accurate characterizations of FBG, sensor network topology and multiplexing method, user interface design and sensor packaging 相似文献
157.
158.
Chen L.R. Benjamin S.D. Smith P.W.E. Sipe J.E. 《Quantum Electronics, IEEE Journal of》1998,34(11):2117-2129
We discuss theoretical and experimental studies on the propagation of ultrashort pulses through fiber Bragg gratings. We also consider several applications in optical communications to be found by combining ultrashort pulses and fiber Bragg gratings: a multiwavelength source for wavelength-division-multiplexed systems and a means for implementing optical code-division multiple access 相似文献
159.
The performance of a multiple-cell direct-sequence code division multiple-access cellular radio system is evaluated. Approximate expressions are obtained for the area-averaged bit error probability and the area-averaged outage probability for both the uplink and downlink channels. The analysis accounts for the effects of path loss, multipath fading, multiple-access interference, and background noise. Two types of differentially coherent receivers are considered: a multipath rejection receiver and a RAKE receiver with predetection selective combining. Macroscopic base station diversity techniques and uplink and downlink power control are also topics of discussion 相似文献
160.