Words into Action: Learning Diverse Humanoid Robot Behaviors using Language Guided Iterative Motion Refinement

Humanoid robots are well suited for human habitats due to their morphological similarity, but developing controllers for them is a challenging task that involves multiple sub-problems, such as control, planning and perception. In this paper, we introduce a method to simplify controller design by enabling users to train and fine-tune robot control policies using natural language commands. We first learn a neural network policy that generates behaviors given a natural language command, such as "walk forward", by combining Large Language Models (LLMs), motion retargeting, and motion imitation. Based on the synthesized motion, we iteratively fine-tune by updating the text prompt and querying LLMs to find the best checkpoint associated with the closest motion in history. We validate our approach using a simulated Digit humanoid robot and demonstrate learning of diverse motions, such as walking, hopping, and kicking, without the burden of complex reward engineering. In addition, we show that our iterative refinement enables us to learn 3x times faster than a naive formulation that learns from scratch

Dynamics, control, stability, diffusion and synchronization of modified chaotic colpitts oscillator with triangular wave non-linearity

The purpose of this paper is to introduce a new chaotic oscillator. Although different chaotic systems have been formulated by earlier researchers, only a few chaotic systems exhibit chaotic behaviour. In this work, a new chaotic system with chaotic attractor is introduced for triangular wave non-linearity. It is worth noting that this striking phenomenon rarely occurs in respect of chaotic systems. The system proposed in this paper has been realized with numerical simulation. The results emanating from the numerical simulation indicate the feasibility of the proposed chaotic system. More over, chaos control, stability, diffusion and synchronization of such a system have been dealt with.Publisher's Versio

Probabilistic Neural Network based Approach for Handwritten Character Recognition

In this paper, recognition system for totally unconstrained handwritten characters for south Indian language of Kannada is proposed. The proposed feature extraction technique is based on Fourier Transform and well known Principal Component Analysis (PCA). The system trains the appropriate frequency band images followed by PCA feature extraction scheme. For subsequent classification technique, Probabilistic Neural Network (PNN) is used. The proposed system is tested on large database containing Kannada characters and also tested on standard COIL-20 object database and the results were found to be better compared to standard techniques

Wear and Friction properties of H-Al-17Si alloy with dry, lubrication and coated (DLC-Star) conditions under HFRR

Dry, lubrication (SAE15W40), and coated (DLC-Star) reciprocating tribological tests on rapid solidified AlSi17Cu3.5-4Mg0.6-0.8 alloy was conducted using a high frequency linear reciprocating rig (HFRR) at ambient temperature. The alloy fabricated with the rheo-stir squeeze casting procedure under T-6 condition. However, at different loading (0-30 N) conditions, wear and friction properties of rapid solidified H-Al-17Si alloy are investigated. It is observed that the lower friction coefficient value obtained for DLC-Star coated H-Al-17Si alloy compared to dry and lubrication conditions. Though, for dry and lubricated sliding, the obtained wear coefficient values are 2.9X10-3 mm3/N.m and 4.0X10-4 mm3/N.m. A lower coefficient of wear value of 5.4X10-5 mm3/N.m was recorded with DLC-star coating under dry conditions. The alloy wear coefficient values first increases with applied load (up to 20 N) and then decreases (20 N to 30 N). EDS, AFM surface roughness profilometer, SEM, and advanced metallurgical microscope (AMM) analysis techniques used for the characterization of surface morphologies. The developments in friction and wear coefficients were fundamentally ascribed to the dispersion and size of primary Si elements and the development of tribo-oxide films on the rapid solidified AlSi17 alloy coated (DLC-Star) surfaces

ASSESSMENT OF IONIZED CALCIUM STATUS IN FEBRILE SEIZURES

Introduction: Epilepsy is one of the most common disorders of the brain1. One of every ten people will have at least one epileptic seizure during a normal lifespan, and a third of these will develop epilepsy. In children the most common forms of convulsion are febrile seizures. Water electrolyte imbalance occurs during acute febrile illness and hypocalcaemia is one of them. Hypocalcaemia is also present in cases of seizures. To find out significance of calcium levels in cases of seizures this study was conducted. Aims and objectives: To assess the level of ionized calcium in cases of febrile seizure. Methods: This Case - Control study was conducted on fifty cases of febrile seizures and fifty age, weight matched controls at Department of Biochemistry, Varun Arjun Medical College, Shahjahanpur,U.P., India. Results: Mean ionized calcium level was 4.62 ±0.26mg/dl and 4.88 ±0.27 mg/dl in study and control groups respectively and this difference was found statistically highly significant (p<0.001). Conclusion: The findings suggest that a considerable percentage of children having febrile seizures suffer from calcium deficiency

ASSESSMENT OF IONIZED CALCIUM STATUS IN FEBRILE SEIZURES

Introduction: Epilepsy is one of the most common disorders of the brain1. One of every ten people will have at least one epileptic seizure during a normal lifespan, and a third of these will develop epilepsy. In children the most common forms of convulsion are febrile seizures. Water electrolyte imbalance occurs during acute febrile illness and hypocalcaemia is one of them. Hypocalcaemia is also present in cases of seizures. To find out significance of calcium levels in cases of seizures this study was conducted. Aims and objectives: To assess the level of ionized calcium in cases of febrile seizure. Methods: This Case - Control study was conducted on fifty cases of febrile seizures and fifty age, weight matched controls at Department of Biochemistry, Varun Arjun Medical College, Shahjahanpur,U.P., India. Results: Mean ionized calcium level was 4.62 ±0.26mg/dl and 4.88 ±0.27 mg/dl in study and control groups respectively and this difference was found statistically highly significant (p<0.001). Conclusion: The findings suggest that a considerable percentage of children having febrile seizures suffer from calcium deficiency

Assessment of environmental impacts by mining activities: A case study from Jhansi open cast mining site - Uttar Pradesh, India

Mining and its allied activities have taken big strikes during the last century contributing significant infrastructure development and raising the living standards of mankind. However, they have also brought in their wake, degeneration and degradation of natural resources, pollution, health risk and socio-ecological instabilities. Bundelkhand region, occupying almost 71818km2 in the central planes of India, is known for its rich deposits of pyrophyllite, moram, salt peter, granite, diasporas, sand, etc. Currently, there are around 325 active mining sites in Jhansi district alone. Deforestation, dust generation, water, air and noise pollution and resource depletion are common hazards associated with opencast mining widely prevalent in this region. The present paper attempts to reveal the base line environmental quality and socio-economic setting in and around such mining sites with special reference to the effects on the air, water, changes of land use pattern and occupational health effects of mine workers etc. It also attempts to provide a framework for management strategies to improve the environmental conditions in the mining sites and its adjoining environments

Modulation of surface meteorological parameters by extratropical planetary-scale Rossby waves

This study examines the link between upper-tropospheric planetary-scale Rossby waves and surface meteorological parameters based on the observations made in association with the Ganges Valley Aerosol Experiment (GVAX) campaign at an extratropical site at Aryabhatta Research Institute of Observational Sciences, Nainital (29.45° N, 79.5° E) during November–December 2011. The spectral analysis of the tropospheric wind field from radiosonde measurements indicates a predominance power of around 8 days in the upper troposphere during the observational period. An analysis of the 200 hPa meridional wind (v200 hPa) anomalies from the Modern-Era Retrospective Analysis for Research and Applications (MERRA) reanalysis shows distinct Rossby-wave-like structures over a high-altitude site in the central Himalayan region. Furthermore, the spectral analysis of global v200 hPa anomalies indicates the Rossby waves are characterized by zonal wave number 6. The amplification of the Rossby wave packets over the site leads to persistent subtropical jet stream (STJ) patterns, which further affects the surface weather conditions. The propagating Rossby waves in the upper troposphere along with the undulations in the STJ create convergence and divergence regions in the mid-troposphere. Therefore, the surface meteorological parameters such as the relative humidity, wind speeds, and temperature are synchronized with the phase of the propagating Rossby waves. Moreover, the present study finds important implications for medium-range forecasting through the upper-level Rossby waves over the study region

Migration/mobility and vulnerability to HIV among male migrant workers: Maharashtra 2007-08

HIV prevalence in Maharashtra is one of the highest among Indian states. The specific objectives of this study were: to understand the patterns and drivers of migration/mobility of men who migrate for the purpose of work in the state of Maharashtra; to describe the characteristics of vulnerable subpopulations among migrant men; and to examine the determinants of high-risk sexual behavior among the subpopulations of migrant men with particular emphasis on the role of mobility in determining the sexual risk behavior. The present study clearly demonstrates that these male migrants, married or otherwise, retain strong connectivity to their native villages, but also show high levels of sexual activity—including significant levels of high-risk sexual activity—making it imperative to study the situation in the sending districts regarding HIV prevalence and spread. The indication from this study is clear: in the context of high-risk sexual behavior (among both married and unmarried migrants) and the low levels of knowledge, condom use, and risk perception, the chances of sending households and districts becoming areas of high HIV prevalence are great. Further exploration of the sexual behavior pattern in sending areas is necessary to obtain additional insights into the possible routes of HIV transmission