Temperature dependent reversal of voltage modulated light emission and negative capacitance in AlGaInP based multi quantum well light emitting devices

We report a reversal in negative capacitance and voltage modulated light emission from AlGaInP based multi-quantum well electroluminescent diodes under temperature variation. Unlike monotonically increasing CW light emission with decreasing temperature, modulated electroluminescence and negative capacitance first increase to a maximum and then decrease while cooling down from room temperature. Interdependence of such electronic and optical properties is understood as a competition between defect participation in radiative recombination and field assisted carrier escape from the quantum well region during temperature variation. The temperature of maximum light emission must coincide with the operating temperature of a device for better efficiency.Comment: 13 pages, 3 set of figure

Design Strategies for Reorganizing the Public Realm of a Neighbourhood Unit: The Case of the Modern Housing Complex, Manimajra, Chandigarh

The Public Realm, an interface between the public and the private, is a vital aspect of the built environment that helps to give a city its identity. Despite being a highly significant contributor towards shaping the urban life and the quality of urban spaces, the fact remains that the concept and idea of meaningful public realm remains largely ignored, especially within neighbourhoods with their series of unmaintained and misused public spaces. Such is the case of the Modern Housing Complex at Manimajra, Chandigarh, where the planned open spaces and parks have been increasingly converted into parking lots, garbage yards with uncontrolled vegetation, or spaces that promote antisocial activities, all of which together affect the livability and attractiveness of the ‘model’ colony.’ This paper is based on a study of Manimajra’s Modern Housing Complex, that was undertaken in 2012-13. The objective was to focus on the public realm and to devise design strategies for a livable neighbourhood through a community-based vision for an improved, high quality Public Realm making the neighbourhood more vibrant, safe and a truly liveable place. The study was based on an understanding of how the physical pattern and organization of a neighborhood influences perception and understanding of public places, multiple forms in which public places are manifested, different ways in which public places are understood, and various manners in which public places are used. The study reinforced the notion that the design, condition and quality of the neighbourhood streets and spaces have a major impact on the quality of its inhabitants’ life, and their careful designing and quality development can help to create successful public places

Impact of British Raj on the Education System in India: The Process of Modernization in the Princely States of India – The case of Mohindra College, Patiala

British rule is said to have been responsible for the modernization witnessed in the Indian civilization. The impact of this process was quiet evident from the changes adopted by the Indians in their life style, thinking processes, attires, food and education. Besides the advancements made in the spheres of roads, transports, postal services etc, their rule acted as a significant period of transition from the indigenous style of education to western education. The foundations were laid by the East India Company and the Christian Missionaries to employ Indians for administrative tasks as well as to serve their political, economical and colonial interests. Originally the access to education was limited to the royal families, as the British were of the opinion that Indians could become aware of their rights and positions and protest against their Raj posing a threat to the British establishment in India. Lord Curzon’s efforts in the 20th century gave way to spread of higher education within the masses and channelized Indian education system. However the rulers of the Princely States in of India who were granted autonomy by the British to manage their own kingdoms acted as major agents to undertake the social and educational reforms within their territories. With the spread of education from elementary to higher levels, many new schools, universities and other institutions were developed during this period which are symbols of educational advancement as well as hold high architectural merit. Patiala, aprime princely state is a well known academic centre also important for its rich culture since the British Raj. Education in Patiala originated under the Maharajas with the opening of the school of languages in 1860A.D. With the introduction of Mahindra College (the first Degree College in a city) in 1870, became came an important educational centre. It was the only college between Delhi and Lahore for a long time that promoted contemporary higher learning in Northern India. The historic college building represents an aesthetic mix of regional interpretation of Indo-Saracenic style of architecture. Later on many educational institutes catering to medical facilities, sports education etc. was set up in this princely state. This paper is thus an attempt to explore the education reforms during the British Raj, the changes that happened and their triggers. It also brings out reforms initiated in Princely States specifically Patiala as a seat of learning and a detailed study of the Mohindra College, Patiala, that represents an excellent example of educational institutions developed during the 19th century. The present study was done as a part of an academic project undertaken during Masters of Architecture under the able guidance of Prof Kiran Joshi..   Search Keywords for This Page: Impact of british education in india, Impact of english education in india, Impact of british education in india pdf, The impact of british education in india, Education system in india during british period, Discuss the negative and positive impact of british education in india, Modernization in education system, What are the impact of british education in india, Education in british india, British education system in india, British education in india, Impact of western education in india, Education and british rule, Impact of british rule in india, Patiala princely state, Impact of modernization on education, Education in india during british rule, Impact of macaulay's minute on indian education, Education system in india during british period pdf, Education in india before british rule, Phulkian states, Education reforms in british india, What were the impact of british education in india, Education system in india before british rule, Princely states of Punja

The Art of Curating an Accessible, Safe & Inclusive City

Building Accessible, Safe, & Inclusive Indian Cities (BASIIC) is an action research programme implemented by the National Institute of Urban Affairs (NIUA) of the Ministry of Housing and Urban Affairs (MoHUA), Government of India. It intends to bring in a paradigm shift in the urban planning and design process by incorporating the tenets of universal accessibility, safety, and inclusivity as the first principle across three levels of government and a wide range of relevant stakeholders. It is supported by the Department for International Development of the UK Government funding through an accountable grant to NIUA. The programme developed through the process of co-creation and multiple rounds of consultation with the key relevant stakeholders and beneficiary groups highlights the value of working with target beneficiaries - persons with disabilities, elderly, women & children (People) as change agents. The transformation in action is the identification of existing gaps in policies and guidelines (Policy) relevant to the above beneficiaries and demystification to a larger group of stakeholders. Outcomes envisaged include more accessible, safe, and inclusive placemaking (Place) for a better quality of life and liveable communities & neighbourhoods. This curation of accessible, safe and inclusive cities through People-Policy-Place (P3) in a collaborative manner with all the quadruple helix actors - government, civil society, academic & research, and industry/start-up on-board is a step towards sustainable development goals

Experimental observation of chimera and cluster states in a minimal globally coupled network

A "chimera state" is a dynamical pattern that occurs in a network of coupled identical oscillators when the symmetry of the oscillator population is broken into synchronous and asynchronous parts. We report the experimental observation of chimera and cluster states in a network of four globally coupled chaotic opto-electronic oscillators. This is the minimal network that can support chimera states, and our study provides new insight into the fundamental mechanisms underlying their formation. We use a unified approach to determine the stability of all the observed partially synchronous patterns, highlighting the close relationship between chimera and cluster states as belonging to the broader phenomenon of partial synchronization. Our approach is general in terms of network size and connectivity. We also find that chimera states often appear in regions of multistability between global, cluster, and desynchronized states

Voltage modulated electro-luminescence spectroscopy and negative capacitance - the role of sub-bandgap states in light emitting devices

Voltage modulated electroluminescence spectra and low frequency ({\leq} 100 kHz) impedance characteristics of electroluminescent diodes are studied. Voltage modulated light emission tracks the onset of observed negative capacitance at a forward bias level for each modulation frequency. Active participation of sub-bandgap defect states in minority carrier recombination dynamics is sought to explain the results. Negative capacitance is understood as a necessary dielectric response to compensate any irreversible transient changes in the minority carrier reservoir due to radiative recombinations mediated by slowly responding sub-bandgap defects. Experimentally measured variations of the in-phase component of modulated electroluminescence spectra with forward bias levels and modulation frequencies support the dynamic influence of these states in the radiative recombination process. Predominant negative sign of the in-phase component of voltage modulated electroluminescence signal further confirms the bi-molecular nature of light emission. We also discuss how these states can actually affect the net density of minority carriers available for radiative recombination. Results indicate that these sub-bandgap states can suppress external quantum efficiency of such devices under high frequency operation commonly used in optical communication.Comment: 21 pages, 4 sets of figure

Dynamics of electronic transitions and frequency dependence of negative capacitance in semiconductor diodes under high forward bias

We observed qualitatively dissimilar frequency dependence of negative capacitance under high charge injection in two sets of functionally different junction diodes: III-V based light emitting and Si-based non-light emitting diodes. Using an advanced approach based on bias activated differential capacitance, we developed a generalized understanding of negative capacitance phenomenon which can be extended to any diode based device structure. We explained the observations as the mutual competition of fast and slow electronic transition rates which are different in different devices. This study can be useful in understanding the interfacial effects in semiconductor heterostructures and may lead to superior device functionality