Voltage Stability Analysis of Grid Connected Embedded Generators

The increasing costs and stringent environmental regulations are making the construction of large power stations to meet rising energy demands economically unfeasible. Hence, Embedded Generation (EG) is predicted to play a prominent role in the electric power systems of the future. The term 'embedded generation' refers to electricity generation connected at distribution level rather than transmission level. The insertion of EGs presents a new set of conditions to distribution networks. The aim of this paper is to conduct a voltage stability analysis using an iterative power system simulation package, PowerWorld (TM) Simulator, to evaluate the impact of strategically placed EG on distribution systems with respect to the critical voltage variations and collapse margins. This paper concludes with the discussion of EG's excellent options for system reactive power compensation and voltage stability

EXPERIMENTAL DESIGN APPROACH TO FABRICATE AND OPTIMIZE FLOATING TABLETS OF LEVOFLOXACIN FOR HELICOBACTER PYLORI INFECTION

Objective: To improve the treatment of H. pylori infection, by achieving the required bactericidal concentrations of antibiotics in the stomach, by delivering the antibiotics to the mucus layer and release the drug at the site of infection for a prolonged period would be significantly more effective than conventional dosage forms. Methods: The experimental method of the research was designed to prepare Levofloxacin floating by using Hydroxypropyl Methylcellulose (HPMC K4M), Hydroxypropyl Methylcellulose (HPMC K100M) and Xanthan gum by Three-level Box–Behnken design optimization method. The prepared tablets were evaluated for Thickness, Hardness, Friability, Weight variation, Swelling index (SI), Floating lag time (FLT) and Time required to release 90% of the drug from the tablet (T90%). Results: It was found that the Thickness-3.12±0.11 mm to 3.28±0.10 mm, Hardness-4.52±0.36 kg/cm2 to 4.81±0.24 kg/cm2, Friability-0.81±0.02g to 0.86±0.12g, Weight variation-480±1.90 mg to 523±0.89 mg, Swelling index (SI)-61.9±0.624% to 99.95±0.226%, Floating lag time (FLT)-81.12±0.63 s to 119.7±0.567 s and Time required to release 90% of the drug from the tablet (T90%)-7.0±0.55 h to 10.33±0.289 h. HPMC K100M and Xanthan gum showed good swelling as compared to HPMC K4M. The study revealed that HPMC K100M grade had a significant effect on drug release. Conclusion: The developed gastro-floating tablets can extend levofloxacin duration in the stomach and produce a prolonged release effect. The prepared levofloxacin floating tablet oral drug delivery system appears to be a promising choice for the efficient eradication of H. pylor

Fabrication and hemocompatibility assessment of novel polyurethane-based bio-nanofibrous dressing loaded with honey and Carica papaya extract for the management of burn injuries

Management of burn injury is an onerous clinical task since it requires continuous monitoring and extensive usage of specialized facilities. Despite rapid improvizations and investments in burn management, >30% of victims hospitalized each year face severe morbidity and mortality. Excessive loss of body fluids, accumulation of exudate, and the development of septic shock are reported to be the main reasons for morbidity in burn victims. To assist burn wound management, a novel polyurethane (PU)-based bio-nanofibrous dressing loaded with honey (HN) and Carica papaya (PA) fruit extract was fabricated using a one-step electrospinning technique. The developed dressing material had a mean fiber diameter of 190±19.93 nm with pore sizes of 4-50 µm to support effective infiltration of nutrients and gas exchange. The successful blending of HN- and PA-based active biomolecules in PU was inferred through changes in surface chemistry. The blend subsequently increased the wettability (14%) and surface energy (24%) of the novel dressing. Ultimately, the presence of hydrophilic biomolecules and high porosity enhanced the water absorption ability of the PU-HN-PA nanofiber samples to 761.67% from 285.13% in PU. Furthermore, the ability of the bio-nanofibrous dressing to support specific protein adsorption (45%), delay thrombus formation, and reduce hemolysis demonstrated its nontoxic and compatible nature with the host tissues. In summary, the excellent physicochemical and hemocompatible properties of the developed PU-HN-PA dressing exhibit its potential in reducing the clinical complications associated with the treatment of burn injuries

A Study of Topology Characteristics on the Real Deployment of Wireless Sensor Networks

This paper investigates the effects of three parameters on the power consumption of sensor motes namely transmit power, frequency channel and sampling rate. Two wireless sensor network (WSN) test-beds have been deployed with two different types of topology; distributed and centralized. The WSN test-beds are built by using Crossbow IRIS motes where the effects of both real indoor and outdoor environment are investigated. Two different scenarios are considered which are line of sight (LOS) and non-LOS for both scenarios. In the case of centralized WSN with star topology, we discovered an interesting finding that the various transmit powers (ranging from 3.2dBm to -17dBm) do not vary the consumed power or in other word, the consumed powers across various transmit powers are almost the same for a given fixed distance value. The only parameter that affects the power consumption is the sampling rate. By increasing the rate, we can reduce the power consumption significantly. In the case of distributed WSN, we discovered that both transmit power and sampling rate affect the power consumption. The transmit power must be reduced and the sampling rate must be increased in order to save power in distributed WSN

Validation of organic management in cassava intercropped in coconut plantation in the humid coastal tropics of Kerala, India

Crop diversification and alternatives like organic farming assume importance for sustainable food production, especially during climate change. Besides, organic farming enables environmentally benign and clean food production. Cassava, an important food-cum-nutritional security crop with diversified uses in feed and industrial sectors, is a common intercrop in coconut plantations. On-station field experiments at ICAR-Central Tuber Crops Research Institute (ICAR-CTCRI), Thiruvananthapuram conclusively proved that organic management promoted productivity, tuber quality and soil properties in cassava. Cost-effective technologies were also developed, which required large scale field validation. Hence, a field experiment was conducted under Network Project on Organic Horticulture during 2015-2017 at the Research Farm, ICAR-Central Plantation Crops Research Institute, Kasaragod, to validate the ICAR-CTCRI developed organic farming technologies in cassava under intercropping in an organically raised mature coconut garden. Three varieties of cassava (Sree Vijaya, Vellayani Hraswa and H-165) were tested under four production systems viz., traditional, conventional, integrated and organic, and replicated thrice in split-plot design in a 48-year-old coconut (var. Kera Keralam) garden. Organic and conventional practices were equally efficient in crop growth, yield, tuber quality and soil chemical properties. Averaging over the years, yield under organic management was 76 per cent of conventional farming. The domestic and industrial varieties of cassava performed similarly under the different production systems, with almost the same yield reduction (24%) under organic over conventional management. The organic technology package comprising farmyard manure, green manure cowpea, cassava crop residue and biofertilizers, resulted in significantly higher available N in soil and improvement in P, K, Mg, Mn and Zn contents in cassava tubers. However, cassava var. Vellayani Hraswa under an integrated production system resulted in the highest net income (` 1,97,830 ha-1) and B:C ratio (1.99) when intercropped in coconut