12 research outputs found
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Intersectoral Convergence and ICTs: Integrated ICT Approaches to Rural Poverty Reduction
As reforms have paved the way for India’s rapid economic expansion in recent years, particularly in the service sector, Information and Communications Technology (ICT) has assumed a dominant role as the underwriter of India’s growth. Outside of the commercial applications where ICT has been most extensively applied so far, ICT also holds great potential to drive human development, narrowing gaps between the rich and the poor as well as rural and urban areas. In many development-adjacent sectors, particularly education, agriculture, and health, platforms and initiatives have already demonstrated ICT’s promise as a transformational suite of technologies which democratize information and dramatically reduce transaction costs.
However, even greater progress is possible if initiatives apply an intersectoral approach which applies best practices from other sectors, highlights synergies between sectors, and identifies pitfalls stemming from hidden competition of priorities between sectors that could otherwise derail a project. Intersectoral analysis also recognizes how advances in the sectors under study contribute to growth in the broader economy. By applying an intersectoral lens, individual programs can be strengthened, new opportunities can be identified, and ICT can be more thoroughly woven into a tapestry that benefits all aspects of people’s lives.
ICT-driven development has not entirely ignored intersectorality, but opportunities abound for improving these initiatives by applying a more holistic lens. In particular, the field of nutrition is most sorely in need of mainstreaming within the many different siloed development objectives that touch upon it. Data, the foundation of ICT, provides great opportunities for refining programs of all types, but also carries great risks to privacy and potentially social equality. And untapped synergies exist between the cutting-edge advances in the Education sector and educational initiatives in other sectors which have not benefited from the same intentional pedagogical design
Frequency-shift free optical phase conjugation using counter-propagating dual pump four-wave mixing in fiber
We propose and numerically verify a novel scheme of frequency-shift free optical phase conjugation by counter-propagating dual pump four-wave mixing in nonlinear fiber. The two counter-propagating pumps create a Bragg grating inside the fiber, which diffracts the forward propagating signal and generates a backward propagating idler wave whose phase is conjugate of signal phase. The two pump frequencies are placed symmetrically about signal frequency to ensure that idler wave will have same frequency as that of signal wave. Since the signal and idler waves appear at opposite ends, the idler is easily filtered out from the rest of the spectrum. Using nonlinear Schrödinger equation, we derive equations of signal and idler evolution. We obtain expressions for idler phase and show that perfect phase conjugation is achieved at an optimum length of fiber for a given pump power. We study the effect of fiber length and pump power on phase conjugation. Simulation results show the perfect phase conjugation at optimum fiber length under lossless conditions and small phase-offset when fiber loss and self and cross phase modulations are included. The small phase-offset is avoided by choosing fiber length smaller than optimum fiber length. Simulation results exhibit close agreement to theoretical values, which validates our simulations
Mitigation of nonlinear effects through frequency shift free mid-span spectral inversion using counter-propagating dual pumped FWM in fiber
We propose and numerically verify a scheme of frequency-shift free mid-span spectral inversion (MSSI) for nonlinearity mitigation in an optical transmission system. Spectral inversion is accomplished by optical phase conjugation, realized by counter-propagating dual pumped four-wave mixing in a highly nonlinear fiber. We examine the performance of MSSI due to critical parameters such as nonlinear fiber length, pump and signal power. We demonstrate the near complete nonlinearity mitigation of 40 Gbps DQPSK modulated data transmitted over 1000 km standard single mode fiber using our method of MSSI. We perform simulation of bit-error rate as a function of optical signal to noise ratio to corroborate the effect of frequency-shift free MSSI
A novel scheme of cascaded four-wave mixing for phase-sensitive amplification in nonlinear optical fibre
We propose and numerically verify a scheme of phase-sensitive amplifier (PSA) using four-wave mixing (FWM) in cascaded highly nonlinear fibres (HNLFs), without requiring initial phase-locking between signal and pump. The first HNLF is used to generate two phase-conjugate waves, which act as two pumps for FWM process in second HNLF. We feed the two pumps from opposite ends of second HNLF and a signal co-propagating with one of the pumps. We keep the signal frequency in the middle of two pump frequencies to obtain phase-conjugate wave at the same frequency as the signal by FWM process in second HNLF. Signal and phase-conjugate wave appear at opposite ends of the second HNLF and combined to obtain PSA. The frequency-shift-free operation of phase conjugation helps in preserving the frequency of input signal during phase-sensitive amplification. We derive the expression for PSA signal output and PSA gain and show analytically that PSA gain depends upon signal phase only, as the two pumps are phase conjugate to each other. Thus, eliminating the need of phase locking between signal and pump waves. We show that PSA provides high gain for in-phase component and almost cancellation for quadrature-phase component of signal. We show the broadband nature of PSA due to minimum effect of group velocity and group velocity dispersion owing to counter-propagating nature of signal and conjugate waves. We study the performance of PSA under the effects of pump-signal detuning, amplifier length and input signal phase. Simulation results show that PSA output is forced to attain 0 or π phase regardless of large variation of phase in the input signal. Nonlinear phase noise reduction of 100 Gbps DPSK signal transmitted over 1000-km standard single-mode fibre confirms phase regeneration by PSA
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ICT-Driven Development in India and Africa
Information and Communications Technology (ICT) has developed into one of the most significant tools at India’s disposal for confronting challenges of development and poverty alleviation. In particular, ICT has proven useful when applied to the fields of agriculture, education, health, governance, and urban development. In recent years, numerous African countries have likewise introduced ICT solutions to various development challenges. While these initiatives have made great contributions, African countries interested in improving their ICT for development programs would greatly benefit from strategic and technical cooperation with India. India faces similar development challenges in an environment of high geographical, social, and economic diversity, making it an ideal testbed for developing interventions which scale in the developing world. Programs which have proven themselves in this context could likely be smoothly adopted to the African context, accelerating the pace of development for African ICT solutions. Ideally, India and Africa could cooperate not just on developing individual platforms, but on formulating an ethical and strategic framework for ICT-driven development which encourages inclusion, respects privacy, and shapes both regions to meet the future demands of the global economy
Compensation of nonlinearity in a fiber-optic transmission system using frequency-degenerate phase conjugation through counter-propagating dual pump FWM in a semiconductor optical amplifier
We present a scheme of frequency-degenerate mid-span spectral inversion (MSSI) for nonlinearity compensation in fiber-optic transmission systems. The spectral inversion is obtained by using counter-propagating dual pump four-wave mixing in a semiconductor optical amplifier (SOA). Frequency-degeneracy between signal and conjugate is achieved by keeping two pump frequencies symmetrical about the signal frequency. We simulate the performance of MSSI for nonlinearity compensation by scrutinizing the improvement of the Q-factor of a 200 Gbps QPSK signal transmitted over a standard single mode fiber, as a function of launch power for different span lengths and number of spans. We demonstrate a 7.5 dB improvement in the input power dynamic range and an almost 83% increase in the transmission length for optimum MSSI parameters of −2 dBm pump power and 400 mA SOA current
Experimental demonstration of optical phase conjugation using counter-propagating dual pumped four-wave mixing in semiconductor optical amplifier
We report optical phase conjugation in C-band by counter-propagating dual pumped non-degenerate four-wave mixing in a semiconductor optical amplifier (SOA). The co-propagating signal and pump waves create a grating inside SOA which diffracts counter-propagating pump and generates the conjugate wave. Since the signal and conjugate waves appear at opposite ends, the conjugate is easily filtered out from the rest of spectrum with minimal spectral shift of the conjugate with respect to the incoming signal. With pump powers of 3.2 dBm each and signal input power of 7 dBm, conjugate power was of 27.2 dBm, giving a conversion efficiency of 1% at 18 GHz pump-signal detuning. By modulating the signal by a periodic pattern ‘1000’ at 10 Gbps using a non-zero chirp intensity modulator and resolving the temporal profile of the electric field envelope of the conjugate wave, we demonstrate spectral in-version
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Delivering Next-Generation Public Services through Mobile Technology
With the ongoing dramatic drop in prices for smartphones in India and the broader developing world, new frontiers are opening up for the incorporation of mobile technology into public service delivery. Mobile services in the fields of education and health have already been widely disseminated, with enormous potential for future growth. Such platforms both improve the quality of the user experience and provide data which can vastly improve the public decision-making process. The expansion of public services into the realm of mobile technology will only be accelerated if governments synchronize the deployment of capable mobile platforms with investments in the digital infrastructure needed to support them. However, while this path presents great promise, it also risks deepening the digital divide. Implementing mobile-based public service delivery presents a number of roadblocks such as India’s relatively low rate of smartphone ownership, broadband infrastructure limitations, and overcoming the legacy of pre-digital institutions. These will need to be addressed in order to facilitate a smooth and inclusive transition towards applying these powerful technologies, but a successful outcome would mean a profound transformation of the Indian economy
Effect of Physico-Chemical Properties of Soil under Various Depths on Different Cropping Systems in Ayodhya, India
A research work conducted during 2018-19 at Agronomy farm of Acharya Narendra Deva University of Agriculture and Technology, Kumarganj, Ayodhya (U.P.) to evaluate the fertility status and effect of different cropping systems on soil physico-chemical characteristics and their correlation. The 300 representative soil samples with 4 depths viz. 0-15, 15-30, 30-60 and 60-90 cm soil samples were taken with manually driven post hole auger and processed for soil analysis from different plots of Agronomy farm. Results revealed that physico-chemical properties viz. particle Density, bulk density pH, EC, organic corban, nitrogen phosphorus potassium Sulphur and zinc varied vertically and horizontally in cultivated and fallow lands. The soils were sandy loam, clay loam, loam and silt loam. The frequency distribution of soil bulk density of entire farm ranged from 1.128-1.58 Mgm-3, particle density ranged 2.50-2.76 Mgm-3 and soil chemical properties, like, pH ranged from 7.2-11.5, the E.C. is found in ranged from .13-1.01 dSm-1. While organic carbon was ranged from 1.4-6.70 g kg-1. and notable available Nitrogen in Agronomy farm was low in ranged from 170.15-221.36 kgha-1.The Phosphorus availability was found in ranged from 6.01-16.87 kgha-1 , while Potassium was found in ranged from 163.20-220.98 kgha-1. How ever the availability of Sulphur, was found in ranged from 8.62-18.32 kgha-1, Zinc ranged from in Agronomy farm 0.28-0.81mgkg-1. The significant positive correlation were observed among soil B.D with N, B.D with P, B.D with K, B.D with S, P.D. with S, P.D. with Zn. While the significant negative correlations were observed among PD with O.C., Zn with P, Zn with K and Zn with S in whole Agronomy Farm