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The stability analysis of the dynamical system of linearized plant model of Advanced Fighter Technology Integration (AFTI)-16 aircraft was proposed along with the optimal control methods by applying linear quadratic regulator (LQR) and linear quadratic algorithm (LQI) algorithms. The LQR and LQI algorithms results were compared with state-space model analysis results. The state-space methods like pole placement method, without using the LQR algorithm the negative feedback system were found to be unstable. By the application of LQR and LQI algorithms to the linearized plant AFTI-16 aircraft open-loop system having negative feedback found to be stable. The stability parameters were verified by using MATLAB programming software. The eigenvalues play a key role in finding closed-loop system stability analysis. MIMO dynamical system with state feedback gain matrices is calculated by using MATLAB programming software.

Street dust from 29 locations, in some of the busiest parts of north and south Kolkata, was analysed for heavy metal composition. The decreasing order of average metal concentrations (mg kg−1) found was Mn (390) > Pb (380) > Zn (300) > As (96) > Cu (61) > Cr (40) > Co (13) > Ag (2.1). The heavy metal composition of the Kolkata dust was compared with reported data for other cities. Enrichment factors of Pb and As were high. Multivariate statistical analysis of the heavy metals and analysis of lead isotopic ratios of the dust revealed a predominant anthropogenic influence in the contamination. The range of lead isotopic ratios found in the dust was between 0.8789 and 0.8998 with a mean Pb concentration of 383 mg kg−1. The three Pb isotope plots of street dust, diesel and rainwater clustered linearly, while coal did not fit into this trend. The highest 207/206 lead isotopic ratio obtained was from diesel with a mean value of 0.9015, followed by the rainwater sample. The application of the binary mixing model showed that about 66.86% of lead contamination in the street dust was sourced from the atmosphere. The two components extracted by the principal component analysis explained 64.34% of the total variance. Vehicular and industrial emissions appeared to be an important contributor to the accumulation of heavy metals in the dust. The health risk assessment study of the dust indicated carcinogenic risk associated with As and Cr.

An extensive database of the isotopic composition as well as content of lead (Pb) has been created in this study from Indian Gondwana coal deposits. Indian Gondwana coal are mostly bituminous to sub–bituminous and occurs as seams inter-banded with sediments. They typically have high ash content (35–50%), which makes them a potential heavy pollutant, considering that very large quantity of coal is burnt for thermal power plants, smelters etc. 110 from different seams spread over the major Indian Gondwana coalfields, that are primarily used for power generation in thermal power plants and fly ash from respective five thermal power plants, have been analysed for their isotopic composition as well as the content of Pb. The results indicate variability of coals from Gondwana basins of India in terms of their concentration and Pb—isotopic ratios. The Pb isotopic composition of Indian Gondwana coals range 0.7150–0.8845 for 207Pb/206 Pb and 1.9484–2.2231 for 208Pb/206 Pb with Pb concentration within 3.2–566 mg kg−1. The variability of the Pb—content and its isotopic composition can be attributed to high and variable ash—content of the coal seams including its pyrite content as well as more radiogenic behaviour. However, within a seam Pb—isotopic ratios vary within a narrow range. Similarly the Pb isotopic composition obtained in the fly ash analyses range 0.8478–0.8757 for 207Pb/206 Pb and 2.1070–2.1706 for 208Pb/206Pb. These values have an increasing trend with respect to the feed coal Pb isotopic compositions when compared to the respective coal—deposits. The inventory generated in terms of Pb isotopic composition and content in Indian Gondwana coals would contribute to establish a background for identifying relative contribution of coal, especially those used in coal-based thermal plants for the Pb pollution in India. Not only this, the unique Pb isotopic composition of coals from south Indian Gondwana coalfields can be compared to the coal deposits of Amrey Group of Antarctica to offer a good constrain to achieve a tighter fit between India and Antarctica in a Gondwana framework and hence can have a wider implication for Gondwana reconstruction, once data set from Amrey Group becomes available.

A geochemical study of the trace metals and lead isotopic ratios of soil and sediments in Korba, Chhattisgarh, India is presented here for the first time. Korba, the nation's ‘power hub’ is also the fifth among its eighty-eight most critically polluted industrial hotspots. A very high mean concentration (in mg kg-1) of V (308), Cr (567), Mn (3442), Co (92), Cu (218), Zn (426), Pb (311), Th (123) and U (32) characterized the sediments of the studied area with mean Igeo values of the trace metals ranging from −2.29 to 3.27. In the two-ratio scatter Pb isotope plot of the different environmental matrices, except for human blood, coal, soil, sediments, non-washed leaves, flyash and diesel overlapped linearly in the mixing line between diesel as the highest anthropogenic end member and a core sediment fraction representing its geogenic counterpart. The mean 207Pb/206Pb Pb ratio decreased in the order of diesel (0.9012) > flyash (0.8757) > coal (0.8498) soils and sediments (0.8374) > lowest core sediment fraction (0.8017). Principal Component Analysis (PCA) of the trace metal data extracted V, Cr, Cu, Zn, Pb, U and Th in the first component PC1. The northeastern part of the study area revealed major hotspots of V, Cu, Co, Zn and Pb near the flyash dykes of the power stations. Human blood used as a biomarker for Pb pollution in this study had a mean blood lead level of 28 μg/dl with a distinctive high 207Pb/206Pb ratio of 0.8828.