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21.
This paper focuses on investigating the current--voltage (I--V) and power--voltage (P--V) characteristics of a photovoltaic (PV) module connected in various configurations like series, parallel, and series-parallel. The performance analysis of PV module has been carried out under uniform and non-uniform conditions such as change in irradiation (passing clouds), change in temperature, accumulation of dust, and change in wind speed using MATLAB-Simulink environment. From the observed results, it has been indicated that for a given number of PV modules, the array configurations affect the maximum available output power and more local maxima are found under partially shaded conditions. Moreover, the comparative analysis of PV module has been performed for various configurations under the above disturbances. From the results, it is evident that even under non-uniform conditions, the parallel configuration of PV modules is more prominent and maximum output power is obtained. Further, parallel layout is particularly convenient for minimizing shadowing effects. The parameters of the PV module have been obtained from the manufacturer datasheet (KC200GT) for these investigations.  相似文献   
22.
Biogeochemical processes in wetland soils are complex and are driven by a microbiological community that competes for resources and affects the soil chemistry. Depending on the availability of various electron acceptors, the high carbon input to wetland soils can make them important sources of methane production and emissions. There are two significant pathways for methanogenesis: acetoclastic and hydrogenotrophic methanogenesis. The hydrogenotrophic pathway is dependent on the availability of dissolved hydrogen gas (H2), and there is significant competition for available H2. This study presents simultaneous measurements of dissolved methane and H2 over a 2-year period at three tidal marshes in the New Jersey Meadowlands. Methane reservoirs show a significant correlation with dissolved organic carbon, temperature, and methane emissions, whereas the H2 concentrations measured with dialysis samplers do not show significant relationships with these field variables. Data presented in this study show that increased dissolved H2 reservoirs in wetland soils correlate with decreased methane reservoirs, which is consistent with studies that have shown that elevated levels of H2 inhibit methane production by inhibiting propionate fermentation, resulting in less acetate production and hence decreasing the contribution of acetoclastic methanogenesis to the overall production of methane.  相似文献   
23.
The present study outlines an approach to classify forest density and to estimate canopy closure of the forest of the Andaman and Nicobar archipelago. The vector layers generated for the study area using satellite data was validated with the field knowledge of the surveyed ground control points. The methodology adopted in this present analysis is three-tiered. First, the density stratification into five zones using visual interpretation for the complete archipelago. In the second step, we identified two island groups from the Andaman to investigate and compare the forest strata density. The third and final step involved more of a localised phytosociological module that focused on the North Andaman Islands. The results based on the analysis of the high-resolution satellite data show that more than 75% of the mangroves are under high- to very high-density canopy class. The framework developed would serve as a significant measure to forest health and evaluate management concerns whilst addressing issues such as gap identification, conservation prioritisation and disaster management—principally to the post-tsunami assessment and analysis.  相似文献   
24.
Worshipping activity is a customary practice related with many religions and cultures in various Asian countries, including India. Smoke from incense burning in religious and ritual places produces a large number of health-damaging and carcinogenic air pollutants include volatile organic compounds (VOCs) such as formaldehyde, benzene, 1,3 butadiene, styrene, etc. This study evaluates real-world VOCs emission conditions in contrast to other studies that examined emissions from specific types of incense or biomass material. Sampling was conducted at four different religious places in Raipur City, District Raipur, Chhattisgarh, India: (1) Hindu temples, (2) Muslim graveyards (holy shrines), (3) Buddhist temples, and (4) marriage ceremony. Concentrations of selected VOCs, respirable particulate matter (aerodynamic diameter, <5 μm), carbon dioxide, and carbon monoxide were sampled from the smoke plumes. Benzene has shown highest emission factor (EF) among selected volatile organic compounds in all places. All the selected religious and ritual venues have shown different pattern of VOC EFs compared to laboratory-based controlled chamber studies.  相似文献   
25.
Phytoplankton species distribution and composition were determined by using microscopy and pigment ratios in the Kongsfjorden during early autumn 2012. Variation in sea surface temperature (SST) was minimal and matched well with satellite-derived SST. Nutrients were generally limited. Surface phytoplankton abundance ranged from 0.21?×?103 to 10.28?×?103 cells L?1. Phytoplankton abundance decreased with depth and did not show any significant correlation with chlorophyll a (chl a). Column-integrated phytoplankton cell counts (PCC) ranged from 94.3?×?106 cells m?2 (Kf4) to 13.7?×?106 cells m?2 (Kf5), while chl a was lowest at inner part of the fjord (6.3 mg m?2) and highest towards the mouth (24.83 mg m?2). Biomass from prymnesiophytes and raphidophytes dominated at surface and 10 m, respectively. The contribution of Bacillariophyceae to biomass was low. Generally, heterotrophic dinoflagellates were great in abundance (12.82 %) and ubiquitous in nature and were major contributors to biomass. Various chl pigments (chl b, chl c, phaeopigments (phaeo)) were measured to obtain pigment/chl a ratios to ascertain phytoplankton composition. Phaeo were observed only in inner fjord. Chl b:a ratios and microscopic observations indicated dominance of Chlorophyceae at greater depths than surface. Furthermore, microscopic observations confirmed dominance of chl c containing algae throughout the fjord. The study indicates that pigment ratios can be used as a tool for preliminary identification of major phytoplankton groups. However, under the presence of a large number of heterotrophic dinoflagellates such as Gymnodinium sp. and Gyrodinium sp., pigment signatures need to be supplemented by microscopic observations.  相似文献   
26.
The global response to the 12 January 2010 earthquake in Haiti revealed the ability to mobilise medical teams quickly and effectively when academic medical centres partner non-governmental organisations (NGO) that already have a presence in a zone of devastation. Most established NGOs based in a certain region are accustomed to managing the medical conditions that are common to that area and will need additional and specialised support to treat the flux of myriad injured persons. Furthermore, an NGO with an established presence in a region prior to a disaster appears better positioned to provide sustained recovery and rehabilitation relief. Academic medical centres can supply these essential specialised resources for a prolonged time. This relationship between NGOs and academic medical centres should be further developed prior to another disaster response. This model has great potential with regard to the rapid preparation and worldwide deployment of skilled medical and surgical teams when needed following a disaster, as well as to the subsequent critical recovery phase.  相似文献   
27.
An oil spill occurred off Goa, west coast of India, on 23 March 2005 due to collision of two vessels. In general, fair weather with weak winds prevails along the west coast of India during March. In that case, the spill would have moved slowly and reached the coast. However, in 2005 when this event occurred, relatively stronger winds prevailed, and these winds forced the spill to move away from the coast. The spill trajectory was dominated by winds rather than currents. The MIKE21 Spill Analysis model was used to simulate the spill trajectory. The observed spill trajectory and the slick area were in agreement with the model simulations. The present study illustrates the importance of having pre-validated trajectories of spill scenarios for selecting eco-sensitive regions for preparedness and planning suitable response strategies whenever spill episodes occur.  相似文献   
28.
Environment, Development and Sustainability - Prayagraj City is one the biggest cities in the State of Uttar Pradesh which has been selected as Smart City by Ministry of Housing and Urban Affairs,...  相似文献   
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30.
The dysgnathia complex (agnathia-otocephaly) (AO) is a lethal malformation that consists of congenital absence of the lower jaw with union or close approximation of the lower ears on the front of the neck, microstomia, and hypoglossia. We present a novel case of agnathia-otocephaly with associated organomegaly and the use of postmortem 3-D computed tomographic rendering. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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