Hyper-parameter optimization of Deep Convolutional Networks for object recognition

Recently sequential model based optimization (SMBO) has emerged as a promising hyper-parameter optimization strategy in machine learning. In this work, we investigate SMBO to identify architecture hyper-parameters of deep convolution networks (DCNs) object recognition. We propose a simple SMBO strategy that starts from a set of random initial DCN architectures to generate new architectures, which on training perform well on a given dataset. Using the proposed SMBO strategy we are able to identify a number of DCN architectures that produce results that are comparable to state-of-the-art results on object recognition benchmarks.Comment: 4 pages, 1 figure, 3 tables, Submitted to ICIP 201

Farming Systems Diversification in North Konkan Region of Maharashtra — An Economic Analysis

The location-specific existing farming systems have been studied for their profitability and extent of diversification in the North Konkan region of Maharashtra. The study is based on the primary data collected from 360 farmers, as well as secondary data on agro-climatic parameters. The study area has been delineated into different clusters/sub- regions using hierarchical agglomerative method. The farming in the North Konkan region has been found highly varied in nature. The enterprises being followed and farm situations are of different nature across different clusters. The farm economy has also depicted a wide variation as per-farm income has been found to range from ` 1135 to ` 218015 across different farming systems. The most profitable farming systems in study area are: (i) Paddy + Irrigated plantation + Betelvines (B:C ratio, 2.02), (ii) Paddy + Pulses + Dairying + Poultry (B: C ratio, 1.74), (iii) Paddy + Vegetables + Dairying ( B:C ratio,1.62), (iv) Paddy + Irrigated plantations + Rainfed plantation + Dairying (B: C ratio,1.57), (v) Irrigated plantations + Dairying (B:C ratio,1.56), and (vi) Paddy + Irrigated plantations + Flowers (B:C ratio,1.42). The diversification has shown a positive co-relation with profitability which underlines the importance of combination of enterprises.Farming systems, Agricultural diversification, North Konkan region, Farm economy, SPSS, Crop diversification index, Agricultural and Food Policy, Q12, Q15,

Computational Modeling of Channelrhodopsin-2 Photocurrent Characteristics in Relation to Neural Signaling

Channelrhodopsins-2 (ChR2) are a class of light sensitive proteins that offer the ability to use light stimulation to regulate neural activity with millisecond precision. In order to address the limitations in the efficacy of the wild-type ChR2 (ChRwt) to achieve this objective, new variants of ChR2 that exhibit fast mono-exponential photocurrent decay characteristics have been recently developed and validated. In this paper, we investigate whether the framework of transition rate model with 4 states, primarily developed to mimic the bi-exponential photocurrent decay kinetics of ChRwt, as opposed to the low complexity 3 state model, is warranted to mimic the mono-exponential photocurrent decay kinetics of the newly developed fast ChR2 variants: ChETA (Gunaydin et al., Nature Neurosci, 13:387-392, 2010) and ChRET/TC (Berndt et al., PNAS, 108:7595-7600, 2011). We begin by estimating the parameters for the 3-state and 4-state models from experimental data on the photocurrent kinetics of ChRwt, ChETA and ChRET/TC. We then incorporate these models into a fast-spiking interneuron model (Wang and Buzsaki., J Neurosci, 16:6402-6413,1996) and a hippocampal pyramidal cell model (Golomb et al., J Neurophysiol, 96:1912-1926, 2006) and investigate the extent to which the experimentally observed neural response to various optostimulation protocols can be captured by these models. We demonstrate that for all ChR2 variants investigated, the 4 state model implementation is better able to capture neural response consistent with experiments across wide range of optostimulation protocol. We conclude by analytically investigating the conditions under which the characteristic specific to the 3-state model, namely the mono-exponential photocurrent decay of the newly developed variants of ChR2, can occurs in the framework of the 4-state model.Comment: 10 figure