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The tannery is one of the leading revenue-generating sectors in developing countries. The ever-increasing demand for leather products in the global market requires converting large amounts of rawhide/skins into resilient non-putrescible finished leather. Only 20% of the raw material is converted into a finished product; the rest 80% is discarded as solid and liquid wastes during leather processing. A heavy discharge of improperly treated solid tannery waste (STW) causes a severe impact on the surrounding environment by polluting soil, surface water, and groundwater resources, posing severe hazards to human and animal health. STW comprises proteinaceous untanned and tanned waste, which requires proper treatment for eco-friendly disposal. Several strategies have been developed over the years for the reduction and recycling of STW for producing renewable energy (biogas and biohydrogen), biofuels (biodiesel and briquettes), construction material, fertilizers, commercial products (adsorbents, animal feeds, proteins, fats, and enzymes), and biodegradable packaging and non-packaging materials. In this review, we discuss various strategies adopted for recycling, reutilization, and reduction of STW in an environment-friendly manner. Furthermore, an overview of the current perspectives toward achieving a zero-waste policy is also presented to reduce the environmental burden using green-clean technology to aid the survival of present-day tanneries. [ABSTRACT FROM AUTHOR]

In laboratories, core cannot always be cut exactly along the axis of symmetry (normal to the bedding plane), which leads to a minor core cutting rotation (CCR) error. The presence of a small CCR error can give rise to an error in computation of anisotropic parameters, which will result in erroneous P-wave and S-wave velocities (V P, V SV and V SH). In this study, we test the sensitivity of Thomson's anisotropic parameters, epsilon (ε), gamma (γ) and delta (δ), to the CCR error. In the vertical transverse isotropy (VTI) system where no rotation exists, values of ε , γ and δ will not vary with azimuth. Similarly, in VTI the values of V P, V SV and V SH, measured at orientations with respect to the axis of symmetry, will also not vary with azimuth. We modelled and analysed the error generated, in anisotropic parameters and phase velocities, due to rotation error of 5° on VTI ANNIE model data, and the Niobrara Shale core sample measurements. For these two cases, we obtained values of P-wave and S-wave velocities along with anisotropy parameters ε , γ and δ , at 0°, 45° and 90° orientations with respect to the axis of symmetry, before and after a rotation of 5°, for different azimuth directions. This study shows that, when the CCR error exists, ε , γ and δ vary with azimuth. For Niobrara Shale samples, we observed that, among all three Thomsen's parameters δ is the most sensitive parameter to the CCR error; when we varied azimuth, we observed a sign change of δ from positive to negative. For ε and γ , variation in azimuth lead to only slight changes in values without any change of sign. The CCR error affects V P and V s measurements the most at 45° orientation, and the least at 90° orientation. The maximum error occurred at 0° azimuth, whereas the minimum error occurs at 90° azimuth. This analysis suggests that, if core cutting rotation exists, phase velocities should be measured at 90° azimuth for accurate results. In laboratories, core cannot always be cut exactly along the axis of symmetry (normal to the bedding plane), which leads to a minor core cutting rotation error. This paper investigates the sensitivity of Thomson's anisotropic parameters, epsilon (ε), gamma (γ) and delta (δ), to the cutting error. [ABSTRACT FROM AUTHOR]

Transmission expansion planning (TEP) has become a complex problem in restructured electricity markets. This article presents the symbiotic organisms search (SOS) algorithm, a novel metaheuristic optimization technique for solving TEP problems in power systems. The SOS algorithm is inspired by the interactions among organisms in an ecosystem. The TEP problem is formulated here as an optimization problem to determine the cost-effective expansion planning of electrical power systems. Several constraints, such as power flow of the lines, right-of-way validity and maximum line addition, are taken into consideration. First, the SOS algorithm is tested with several benchmark functions. Then, it is applied on three standard power system networks (IEEE 24-bus system, Brazilian 46-bus system and Brazilian 87-bus system) in a TEP study to demonstrate the optimization capability of the proposed SOS algorithm. The results are compared with those produced by other state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

In today’s competitive electricity market, managing transmission congestion in deregulated power system has created challenges for independent system operators to operate the transmission lines reliably within the limits. This paper proposes a new meta-heuristic algorithm, called as symbiotic organisms search (SOS) algorithm, for congestion management (CM) problem in pool based electricity market by real power rescheduling of generators. Inspired by interactions among organisms in ecosystem, SOS algorithm is a recent population based algorithm which does not require any algorithm specific control parameters unlike other algorithms. Various security constraints such as load bus voltage and line loading are taken into account while dealing with the CM problem. In this paper, the proposed SOS algorithm is applied on modified IEEE 30- and 57-bus test power system for the solution of CM problem. The results, thus, obtained are compared to those reported in the recent state-of-the-art literature. The efficacy of the proposed SOS algorithm for obtaining the higher quality solution is also established. [ABSTRACT FROM AUTHOR]

In today’s competitive electricity market, managing transmission congestion in deregulated power system has created challenges for independent system operators to operate the transmission lines reliably within the limits. This paper proposes a new meta-heuristic algorithm, called as symbiotic organisms search (SOS) algorithm, for congestion management (CM) problem in pool-based electricity market by real power rescheduling of generators. Inspired by interactions among organisms in ecosystem, SOS algorithm is a recent population-based algorithm which does not require any algorithm specific control parameters unlike other algorithms. Various security constraints such as load bus voltage and line loading are taken into account while dealing with the CM problem. In this paper, the proposed SOS algorithm is applied on modified IEEE 30- and 57-bus test power system for the solution of CM problem. The results, thus, obtained are compared to those reported in the recent state-of-the-art literature. The efficacy of the proposed SOS algorithm for obtaining the higher quality solution is also established. [ABSTRACT FROM AUTHOR]

Power sector reform, which circumscribes independent regulatory commission, unbundling of the State Electricity Boards (SEBs), and eventual privatization, has been the dominant theme in the Indian economic policy discourse and power sector. In India, the power sector reforms were initiated in 1991 and began with the concurrence of the private investors in generation, and then centralized on the unbundling of vertically integrated utilities. In this paper, an attempt has been made to analyze the changing importance of energy conservation and efficiency measures been initiated in India between 1970 and 2013. The study also examines how far the reform process has been effective in realizing its set objectives and ameliorates the development of the power sector and the nation unrestrained. The paper briefly discusses the issue involved in the introduction of competition in the power sector primarily through the development of a market for bulk power, and a careful comparison of the costs and benefits of the old regulated system and the new deregulated system is made. [ABSTRACT FROM AUTHOR]

Noise reduction is important for signal analysis. In this paper, we propose a hybrid denoising method based on thresholding and data-driven signal decomposition. The principle of this method is to reconstruct the signal with previously thresholded intrinsic mode functions (IMFs). Empirical mode decomposition (EMD) based methods decompose a signal into a sum of oscillatory components, while variational mode decomposition (VMD) generates an ensemble of modes with their respective centre frequencies, which enables VMD to further decrease redundant modes and keep less residual noise in the modes. To illustrate its superiority, we compareVMDwithEMDas well as its derivations, such as ensembleEMD(EEMD), complete EEMD (CEEMD), improved CEEMD (ICEEMD) using synthetic signals and field seismic traces. Compared with EMD and its derivations, VMD has a solid mathematical foundation and is less sensitive to noise, while both make it more suitable for non-stationary seismic signal decomposition. The determination of mode number is key for successful denoising. We develop an empirical equation, which is based on the detrended fluctuation analysis (DFA), to adaptively determine the number of IMFs for signal reconstruction. Then, a scaling exponent obtained by DFA is used as a threshold to distinguish random noise and signal between IMFs and the reconstruction residual. The proposed thresholded VMD denoising method shows excellent performance on both synthetic and field data applications. [ABSTRACT FROM AUTHOR]

This analysis examined trends in incidence and survival among US adults with myeloproliferative neoplasms, including essential thrombocythemia (ET; n = 14,676), polycythemia vera (PV; n = 15,141), and primary myelofibrosis (PMF; n = 4214), using Surveillance, Epidemiology, and End User Results (SEER) data (SEER 18; 2002–2016). Incidence and survival rates over the study period and by diagnosis year (per 5-year time frames: 2002–2006; 2007–2011; 2012–2016) were assessed. The overall incidence rates (95% CI) were 1.55 (1.52–1.57) for ET, 1.57 (1.55–1.60) for PV, and 0.44 (0.43–0.45) per 100,000 person-years for PMF, with rising ET incidence. Five-year mortality over the study period was 19.2%, 19.0%, and 51.0% for ET, PV, and PMF, respectively. Improved survival over time was observed for PV and PMF, but not for ET. These findings highlight the need for effective ET therapies, as ET incidence has risen without concurrent improvements in survival over the past 2 decades. [ABSTRACT FROM AUTHOR]