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471.
The Indian energy scene has undergone a distinct change during the last three decades. In overall terms the reliance on traditional (non-commercial) forms of energy has declined gradually and the share of modern commercial forms of energy has steadily increased. The preference towards commercial forms of energy has resulted in rapid growth of demand, and the growth rate of commercial energy consumption has outpaced the overall growth of the economy. While India has been able to manage oil supplies without much difficulty through indigenous production and imports, there have been balance of payments problems due to the steep increase in the import bill. An overall energy strategy has been formulated for the Sixth Five-Year Plan which will ensure adequate supplies of energy to meet short-term energy requirements while keeping in view the long-term perspective. The plan envisages achieving a balance between energy supplies and demand in the short and medium term by accelerating exploitation of domestic conventional energy resources and managing demand through appropriate measures. In the long term, exploitation of new and renewable energy resources is the basis of energy development strategy. La situation énergétique en Inde a subi une transformation distincte durant ces trois dernières décennies. En termes généraux, la dépendance vis-à-vis des formes traditionnelles d'énergie (non-commerciales) a diminué graduellement et les formes commerciales modernes d'énergie se sont accrues d'une manière constante. La préférence pour les formes commerciales d'énergie a eu pour résultat l'accroissement rapide de la demande et le taux de croissance de la consommation énergétique commerciale a surpassé la croissance totale de l'économie. Alors que I Inde a été capable de s'approvisionner en pétrole sans trop de difficulté par des moyens de production indigéne et d'importations, des problèmes de balance de paiements sont survenus à cause de l'augmentation aiguë de la facture énergétique. Une stratégie globale en matière d'énergie a été formulée pour inclusion dans le sixième plan quinquennal, ce qui assurera des approvisionnements en energie adéquats pour faire face aux exigences énergétiques à court terme tout en gardant en vue les objectifs à long terme. Le plan envisage d'atteindre un équilibre entre l'offre et la demande en matière d'énergie à court et moyen termes en accélérant l'exploitation des ressources énergétiques conventionnelles du pays et en contrölant la demande par des mesures appropriées. A long terme, la base de la stratégie du développement en matière d'énergie consiste en l'exploitation des ressources énergétiques nouvelles et renouvelables. La escena energética de la India a sufrido un cambio marcado durante las últimas tres décadas. En general la dependencia en la energia no comercial a declinado gradualmente mientras que el uso de recursos de energia comercial ha aumentado continuamente. Esto ha generado una rápida tasa de creamiento de la demanda de energia comercial que supera la tasa de crecimiento económico. A pesar de que la India pudo satisfacer sus necesidades de petróleo mediante producción propia e importaciones hay problemas en la balanza de pagos. Se ha formulado estrategia general para el Sexto Plan Quinquenal que asegurará el suministro en el corto plazo sin descuidar la perspectiva a largo plazo. El plan prevee obtener el balance de la oferta y la demanda en el corto y mediano plazo mediante una exploración acelerada y una apropiada administración de la demanda. Para el largo plazo, la explotación de recursos nuevos y renovables de energia es la base de la estrategia de desarrollo energético.  相似文献   
472.
ABSTRACT: Nutrient diversion does not always bring about prompt and sufficient reduction in lake phosphorus concentration due to recycling from nutrient rich sediments. Certain lakes and reservoirs may continue to experience nuisance algal blooms and require additional restorative steps. The phosphorus precipitation/inactivation technique is a procedure to remove phosphorus from the water column and to control its release from sediments in order to achieve P-limiting conditions to algal growth. Aluminum salts have been used in advanced waste water treatment to remove phosphorus and this technology was extended to lake rehabilitation. Guidelines for dose calculation and application are generally lacking, and are provided in this report. The dose determination suggested here allows maximum application of aluminum to bottom sediments and thus emphasizes long term control of phosphorus recycling. Dose can be calculated directly from the alkalinity of the water to be treated. Titration of lake water samples of Varying alkalinity allows the establishment of the relationship between residual dissolved aluminum, alkalinity, and dose which can then be employed for lake scale applications of alum to lakes and reservoirs. Application equipment and procedures are described. These depend on site characteristics and treatment objectives and include lakeside stores, a distribution pipe, and an application barge and manifold. Alum may also be used to meet other restoration objectives including the treatment of problem flows and the reduction of particulate concentrations.  相似文献   
473.
ABSTRACT: The detection of change in a hydrologic varaible, particularly water quality, is a current problem. A method is presented for testing whether there has been a shift in the mean of a hydrologic variable based on the well established bivariate normal distribution theory. In this technique, the dependent, or target, and the independent, or control, variables are formed as weighted linear combinations of the mean values at a number of locations in a selected target and control area. The weighting factors are determined based on a mathematical programming technique which minimizes the conditional coefficient of variation thereby minimizing the number of observations required to detect a change of a preselected magnitude in the mean of the target area. The result is a situation where a savings in the number of observations required to detect a change is a consequence of adding more stations: the space-time tradeoff. Two applications of the technique are presented, the first using electrical conductivity (EC) data from two sets of river basins and the second using EC data from a set of basins as the target variable and annual discharge as the control. The results indicate that a significant savings in time can be achieved by using this method.  相似文献   
474.
ABSTRACT: The cost of sanitary facilities is a major cost item in recreation areas at water resources projects. Often planners wish to analyze the tradeoffs in providing different levels of service at these areas. Cost functions are presented in this paper to enable the planner to make quick comparisons between different types of buildings, sizes, exterior treatments, and number of fixtures.  相似文献   
475.
This note examines the second-order conditions of the Massel-Parrish (M-P) model of a beverage market in which a monopolist producer of beverages packaged in ‘private mould’ bottles has monopsony power in the market for the empty bottles. Customers pay only the shelf price if they return the empty bottle; and, the shelf price plus the forfeited deposit if they discard it. The analysis determines directional changes in the optimal shelf price, deposit levels, and unit sales resulting from changes in each of five demand and three supply parameters. Potential effects of current legislation requiring mandatory deposits on all beverage containers are also analysed.  相似文献   
476.
ABSTRACT: Decisionmaking associated with the Nation's 1.7 billion acres of forest and range land has become increasingly complicated because of the rise in competition for resource use and in the awareness of environmental and social effects. This system analysis approach uses four models to synthesize pertinent masses of information into measures of economic, environmental, and social impacts. The system results can be used to help evaluate alternative national programs. The models are:
477.
In many situations, the effect of a toxic chemical on a biological system depends on both the intensity and the duration of exposure. The dependence on the time dimension can be the expression of a range of processes including the physical accumulation of toxic chemicals or their metabolites and the functional accumulation of damage. Measures and functions that have been used to describe this dependence are reviewed.Some of these functions are compared through a case study of the neurotoxicity of methylmercury. Use is made of data that indicates a dependency between the blood concentration at which monkeys were exposed and the length of time before damage was detected. Several exposure functions are fitted to these data and their appropriateness is compared. Using the most appropriate function, an exposure-response relationship is developed using probit analysis. An alternative data analysis procedure is also investigated. The apparent threshold after a 100 day exposure is estimated to be greater by a factor of 3–5 compared to the threshold for chronic exposure. Applying this factor to man, the blood concentration threshold for chronic exposure is estimated to be 40–170 ppb, a finding consistent with recent reports of neurological damage in humans exposed below the generally accepted threshold.  相似文献   
478.
DABSE, a database for avian blood spot examination for exposure to toxicants, is a new biomonitoring project in wild birds that has the goal of providing reference values of harmful agents, as measured in whole blood stored as dried blood spots. Once these "normal" values have been established, the diagnosis of environmental contaminant-mediated ill-health (such as manifestations of sickness, increased mortality, a reduction in population, poor breeding success, abnormal behavior) in an individual bird or in a population could be facilitated by comparing exposure values in the investigation to reference values of the same species in the database. One might then identify the cause and pave the way for a mitigating response. The toxicant component of DABSE is being examined at the low ng ml(-1) level in 200 μl of whole blood. As these analyses are invariably very costly, an effort has been made to lower these costs and so enable more testing by quantitating representative compounds as markers for the whole group. These markers are invariably found in birds' blood at the highest concentration of all the constituents in that group. The toxicant groups comprise:- (a) elements-arsenic, cadmium, lead, mercury and selenium; (b) organochlorine pesticides, markers being p,p'-DDT, p,p'-DDE, β-HCH, HCB and oxychlordane; (c) polychlorinated biphenyls (PCBs), the marker being congener 153; (d) polybrominated diphenyl esters (PBDEs), the marker being congener 47; (e) perfluorinated compounds (PFCs), the markers being perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). DABSE will be expanded to determine exposure to infectious diseases and perhaps acute toxicoses.  相似文献   
479.
The river Ganges has been one of the major recipients of industrial effluents in India. The present paper deals with the study related to occurrence and bioaccumulation of heavy metals (Cu, Cr, Cd, Pb, Zn) in the riverine water, sediment, and the muscles of two cat fish species, Channa punctatus (C. punctatus) and Aorichthys aor (A. aor) procured from the river Ganges at Allahabad. The data obtained after water analysis reflected the order of occurrence of heavy metals to be Zn > Pb > Cu > Cr > Cd, respectively. The analysis of heavy metals in sediment indicated that among the five heavy metals tested; Zn was maximally accumulated followed by Pb, Cr, Cu and Cd. The trend of heavy metals accumulation in fish muscles was found to be similar to that observed in sediment and water such as Zn > Pb > Cu > Cr > Cd. Data indicated that Zn accumulated maximally in the sediment as well as muscles of both of the fish species in comparison to other metals.  相似文献   
480.
Laboratory experiments conducted during 1987 on Appledore Island, Maine, USA, tested whether feeding preference or the absence of an attractant was the cause for the occurrence of beds of Codium fragile ssp. tomentosoides (herein referred to as Codium fragile) within rocky barrens grazed clear of kelp by the sea urchin Strongylocentrotus droebachiensis. Consumption of C. fragile in single-diet experiments (1 seaweed/sea urchin) was highly variable and was not significantly different from that for several other seaweeds (Agarum cribrosum, Ascophyllum nodosum, Chondrus crispus, and Laminana saccharina) important in the field diet of the green sea urchin. In multiple-diet experiments (5 seaweeds/sea urchin) significantly less Codium fragile was eaten than Chondrus crispus, but significantly more Codium fragile was eaten than A. cribrosum. Chemosensory experiments suggest that C. fragile does not attract the sea urchin. Sea urchins are unable to detect C. fragile but will eat it when they come in contact with it.  相似文献   
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