1,149 research outputs found

    State Estimation for Electric Power System with Load Uncertainty and False Data Using Cuckoo Search Algorithm

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    State estimate serves a crucial purpose in the control centre of a modern power system. Voltage phasor of buses in such configurations is referred to as state variables that should be determined during operation. A precise estimation is needed to define the optimal operation of all components. So many mathematical and heuristic techniques can be used to achieve the aforementioned objective. An enhanced power system state estimator built on the cuckoo search algorithm is described in this work. Several scenarios, including the influence of load uncertainty and the likelihood of false data injection as significant challenges in electrical energy networks, are proposed to analyses the operation of estimators. The ability to identify and correct false data is also assessed in this regard. Additionally, the performance of the presented estimator is compared to that of the weighted least squares and Cuckoo Search algorithm. The findings demonstrate that the Cuckoo search algorithm overcomes the primary shortcomings of the conventional approaches, including accuracy and complexity, and is also better able to identify and rectify incorrect data. On IEEE 14-bus and 30-bus test systems, simulations are run to show how well the method works

    Grey Wolf Optimizer and Cuckoo Search Algorithm for Electric Power System State Estimation with Load Uncertainty and False Data

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    State estimate serves a crucial purpose in the control centre of a modern power system. Voltage phasor of buses in such configurations is referred to as state variables that should be determined during operation. A precise estimation is needed to define the optimal operation of all components. So many mathematical and heuristic techniques can be used to achieve the aforementioned objective. An enhanced power system state estimator built on the cuck search algorithm is described in this work. Several scenarios, including the influence of load uncertainty and the likelihood of false data injection as significant challenges in electrical energy networks, are proposed to analyse the operation of estimators. The ability to identify and correct false data is also assessed in this regard. Additionally, the performance of the presented estimator is compared to that of the weighted least squares, Cuckoo Search algorithm and grey wolf Optimizer. The findings demonstrate that the grey wolf Optimizer overcomes the primary shortcomings of the conventional approaches, including accuracy and complexity, and is also better able to identify and rectify incorrect data. On IEEE 14-bus and 30-bus test systems, simulations are run to show how well the method works

    Human papillomavirus infection in esophageal squamous cell carcinoma and esophageal adenocarcinoma: a concise review

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    The causal link between high-risk human papillomavirus (hr-HPV) infection and cervical, anogenital, and some oropharyngeal malignancies has been established by both molecular and epidemiological data. The association between HPV and esophageal squamous cell carcinoma (ESCC) remains controversial, as is the true prevalence of HPV infection in ESCC. The wide range in reported rates reflects variability in the primary literature, with some larger scale case–control studies suggesting the infection rates range from 0% to 78%. Interactions between HPV and the Barrett's metaplasia–dysplasia–carcinoma sequence have been explored, and these studies have shown some conflicting data. Overall, systematic reviews have reported the prevalence of HPV-positive DNA in esophageal adenocarcinoma patients of between 13% and 35%. Postulated reasons for discrepancies in HPV prevalence rates in esophageal cancer include variations in testing methodology and assay sensitivities; technical issues, including the lack of a gold-standard primer; types of specimens utilized (fresh-frozen versus formalin-fixed tissue); geographical variation; cross-contamination; and small sample sizes. Thus, efforts must be undertaken to (1) standardize HPV testing, ideally in a central laboratory and utilizing tests that detect viral transcriptional activity; (2) avoid cross-contamination; and (3) recruit large numbers of patients to accurately ascertain HPV rates in esophageal malignancy

    Soil fertility status of coconut and arecanut growing soils

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    The present study was undertaken to assess the soil fertility status of major coconut and arecanut growing soils in different agro-climatic conditions of Karnataka. Based on the agro-climate variability, thirty typical soil pedons representing five different agro-climatic zones (ACZs) of Karnataka, namely, eastern dry zone (EDZ), southern dry zone (SDZ), southern transitional zone (STZ), hilly zone (HZ), and coastal zone (CZ) were studied for their physicochemical properties. The study revealed that soils of semi-arid (EDZ and SDZ) and sub-humid (STZ) zones have near neutral to moderately alkaline reaction and humid region soils (coastal and hilly zones) have high acidity. The soils are non-saline with low cation exchange capacity. Greater soil organic carbon was recorded in arecanut soils than coconut under all ACZs except coastal zone. The major nutrients status of the soil samples indicated that the available nitrogen is low in all the pedons; the pooled data of available nitrogen content was higher in arecanut (166.3 kg ha-1) than coconut (152.6 kg ha-1), and hilly zone soils recorded higher available nitrogen. A wide range of available P2O5 was noticed in coconut and arecanut soils, ranging from 1.0 to 64.2 kg ha-1. The coconut soils (11.5 kg ha-1) recorded higher available P2O5 than arecanut soils (9.62 kg ha-1) when data were pooled. The soils were low to medium in available potassium, and a higher available K2O content was recorded in arecanut soils (151.7 kg ha-1) compared to coconut (110.1 kg ha-1). The available K2O ranged from 66.8 to 511.7 kg ha-1 in the surface and 37.6 to 461.2 kg ha-1 in sub-surface soils

    Reproductive biology of the commercially important Uroteuthis (Photololigo) duvaucelii (d’ Orbigny [in 1835) off Mangalore, south-west coast of India

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    Uroteuthis (Photololigo) duvaucelii is one of the commercially important inshore squid resources off the south-west coast of India. Length-weight relationship for this species indicated no significant difference between the sexes and hence, the relationship for both the sexes was represented with the common equation W = 0.4624 L2.1158. U. (P.) duvaucelii spawned throughout the year with peak spawning in May. Absolute fecundity ranged from 1,545 to 13,585 eggs with an average of 7,554 eggs. Size at first maturity indicated that females matured earlier at 70 mm DML (dorsal mantle length) whereas males matured little later at 90 mm DML. Males were observed to be dominant during most of the study period with overall male to female ratio of 1:0.93. Seasonal and size dependent variations in sex ratio were distinct

    Yb(OTf)3 Catalyzed Synthesis, Antimicrobial and Insecticidal activity of some Biscoumarins

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    Published ArticleIn the present study, we report Yb(OTf)3 catalyzed synthesis of biscoumarins by pseudo three-component reaction of aldehyde and 4-hydroxycoumarin. The synthesized biscoumarins were evaluated for antimicrobial and insecticidal activity. Results of antimicrobial activity were found to be moderate to good in terms of zones of inhibition and MIC values against E. coli, P. vulgaris and S. aureus. The compounds were inactive against the used fungal strains except B4 in case of Penicillium. Insecticidal activity of the biscoumarins B-1, B-3, B-5 and B-11 was found to be good exhibiting 70-75% mortality effect on Callosobruchus maculatus

    Characterization and classification of major coconut growing soils in South Eastern Ghats of Tamil Nadu, India

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    Six soil series representing major coconut growing soils of the Eastern Ghats in Krishnagiri district of Tamil Nadu State, India, were evolved from granite gneiss and alluvium parent materials. Characterization of different soil properties was done using a detailed soil survey at 1:10000 scale. The soils were neutral to moderately alkaline in reaction (7.31 to 9.19), non-saline, poor to moderately well-drained and moderately shallow (<75 cm) to very deep (>150 cm) in depth. The soils were sandy to clay in texture, sub-angular blocky to crumb in structure, dark reddish-brown to brown, very low to high in OC content (0.06 to 2.70%), low to medium in AWC (3.44 to 22.39%), low to high in CEC (4.70 to 54.0 cmol (p+) kg-1) and having high base saturation (77 to 100%). The soils also had sizable amounts of exchangeable sodium (4.29 to 33.46%), which was maximum in P5, P6 and P1, and high clay content in P5 and P2. The distribution of CaCO3 in different depths was found to be maximum in P4 and P1. The soil orders identified in the coconut area were Inceptisols, Entisols, Alfisols and Vertisols. Assessment of soil resources and identification of yield-limiting soils factors on coconut could be by way of better management and improved productivity
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