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71.
Shiv Prasad Kosta Vimal Patel Shakti Kosta Y. P. Kosta 《International Journal of Electronics》2013,100(2):117-120
For the first time a biomass bistable transistor multivibrator using an NPN Philips transistor as the active device and freshly plucked green Champo (Plumaria rubra) leaf cuttings as electrical components (resistance R and capacitance C) has been realized. The frequency and other parameters of the generated pulses, along with the circuit configuration, are presented. The development envisages a novel march towards a green revolution in electronic circuitry. 相似文献
72.
利用基于扫描相机的荧光寿命成像显微技术研究细胞周期 总被引:1,自引:1,他引:1
利用基于扫描相机的荧光寿命成像显微系统,以细胞周期为模型,研究转染绿色荧光蛋白的HeLa细胞的荧光寿命。结果表明,处于周期内不同进程的细胞的荧光寿命为2.50~3.00 ns。处于分裂期的细胞的荧光寿命在1 h内从2.86 ns下降到2.82 ns;在DNA合成前期的8 h内,荧光寿命从2.82 ns下降到2.78 ns。荧光寿命的差异反映了细胞周期中核浆内大分子浓度的变化,对了解细胞周期的分子机制有一定的意义。 相似文献
73.
Wireless Networks - Unmanned Aerial Vehicles (UAVs) deployed as flying base stations is a promising technology for enhancing the quality of service (QoS) and quick recovery from unexpected damages... 相似文献
74.
Neeli R. Prasad Mahbubul Alam Marina Ruggieri 《Wireless Personal Communications》2004,29(3-4):205-219
Security and privacy architecture for various access networks have often been considered on the upper service layers in the form of application and transport security and from lower layers in the form of security over wireless networks. Today there is no trust relationship between the stakeholders of different access network types for e.g. wireless mesh network, wireless PAN, wireless LAN, cellular network, satellite etc. and each have their own security mechanism. What is common for these access networks is the networking layer which is IP based. In order to provide seamless service across these heterogeneous access networks there must be a trust relationship among the stakeholders for authentication, authorization, accounting and billing of end user. However, what is still missing is a general solution which is both adaptable to the network types and conditions and also takes into account end system capabilities as well as enabling inter-domain AAA negotiation. This paper proposes a light-weight AAA infrastructure providing continuous, on-demand, end-to-end security in heterogeneous networks. 相似文献
75.
Ajay Singh S. Samanta Arvind Kumar A.K. Debnath R. Prasad P. Veerender Vishal Balouria D.K. Aswal S.K. Gupta 《Organic Electronics》2012,13(11):2600-2604
Charge transport and gas sensing characteristics of cobalt phthalocyanine films deposited along (ATB) and perpendicular (PTB) to the natural twin boundaries of (0 0 1) LaAlO3 substrate have been investigated. The charge carrier mobility of ATB films (∼5 cm2 V−1 s−1) is five orders of magnitude higher compared to that of PTB films (∼7 × 10−5 cm2 V−1 s−1), suggesting that twin boundaries acts like a template for ordering of molecules. The ATB films on exposure to ammonia showed a reversible increase of resistance, with fast response and recovery. In contrast PTB films showed same sensitivity, but exhibits base resistance drift along with sluggish response. 相似文献
76.
Marchetti N. Cianca E. Prasad R. 《Wireless Communications, IEEE Transactions on》2009,8(11):5388-5393
This letter addresses the application of Linear Dispersion Codes (LDC) in space and frequency domains in Single Carrier - Frequency Domain Equalization (SCFDE) systems. Space-Frequency (SF)-LDCs are more suitable than Space- Time (ST)-LDC in high mobility environments. However, the application of LDCs in space and frequency domains in SCFDE systems is not straightforward as in Orthogonal Frequency Division Multiplexing (OFDM) systems because in this case there is no direct access to subcarriers at the transmitter. This letter shows that it is possible to induce a target SF symbol dispersion in SCFDE by using a simple linear pre-coder and a conventional LDC that spreads the symbols in time and space domains according to specific ST dispersion matrices. The letter shows how to derive the ST dispersion matrices to be used at the transmitter as a function of the dispersion matrices describing the target SF dispersion. The presented procedure can be applied to both pure transmit diversity and pure multiplexing schemes, which are special cases of LDCs. Therefore, the proposed scheme provides a low complexity implementation of any dispersion in space and frequency over SCFDE systems, which alternatively would require the use of FFT/IFFT also at the transmitter side. The letter also shows a performance comparison of SF-LDCs and ST-LDCs in a typical propagation environment for future radio systems. The comparison confirms the suitability of using the dispersion in frequency rather than time for a wide range of coherence bandwidths. 相似文献
77.
Shiv Prasad Kosta Y. P. Kosta Vimal Patel Ritu Jain Shakti Kosta Sonal Sharma 《International Journal of Electronics》2013,100(10):599-609
For the first time, a biomass electronic junction functioning as a conventional electronic diode inside green leaves of Vinka-rosa and Plumeria rubra mass structure has been experimentally predicted and studied. The experimental diode demonstrated appropriate conventional electronic diode characteristics. The predicted diode junctions were operated for forward and reverse dc voltage biases in the range of ±1 to 10 and 1 to 30?V respectively. The studies revealed a strong functional dependence on the water content of the green leaf. These studies are sequential to the very recently reported research work of Kosta et al. on bioelectronics and soilelectronics. The study speculatively forecasts the beginning of a new revolutionary era of green biomass electronic circuitry. 相似文献
78.
Semiconductors - In this work, drain current ID for 5-nm gate length with dual-material (DM) double-surrounding gate (DSG) inversion mode (IM) and junctionless (JL) silicon nanotube (SiNT) MOSFET... 相似文献
79.
Dnyaneshwar Mantri Neeli Rashmi Prasad Ramjee Prasad 《Wireless Personal Communications》2014,76(3):335-349
In recent years, energy consumption and data gathering is a foremost concern in many applications of wireless sensor networks (WSNs). The major issue in WSNs is effective utilization of the resource as energy and bandwidth with a large gathering of data from the monitoring and control applications. This paper proposes novel Bandwidth Efficient Cluster based Packet Aggregation algorithm for heterogeneous WSNs. It combines the idea of variable packet generation rate of each node with random data. The nodes are randomly distributed with different energy level and are equal in numbers. It uses the perfectly compressible aggregation function at cluster head based on the correlation of packets and data generated by each node. Compare to state-of-the-art solutions, the algorithm shows 4.43 % energy savings with reduced packet delivery ratio (62.62 %) at the sink. It shows better bandwidth utilization in packet aggregation than data aggregation. 相似文献
80.
Brajesh Kumar Kaushik Sankar Sarkar Rajendra Prasad Agarwal R.C. Joshi 《Microelectronics Journal》2010,41(2-3):85-92
This paper deals with waveform analysis, crosstalk peak and delay estimation of CMOS gate driven capacitively and inductively coupled interconnects. Simultaneously switching inputs for the coupled interconnects are considered. A transmission line-based coupled model of interconnect is used for analysis. Alpha-power Law model of MOS transistor is used to represent the transistors in CMOS driver. Peaks and delays at far-end of victim line are estimated for conditions when the inputs to the two coupled interconnects are switching in-phase and out-of-phase. The comparison of analytically obtained results with SPICE simulations show that the proposed model captures noise peak and their timing; 90% propagation delay; transition time delay and waveform shape with good accuracy, such as not more than 5% error in crosstalk peak estimation. 相似文献