Documents found
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115991.More information
Fiduciary duties are critical to the integrity of a remarkable variety of relationships, including those between trustee and beneficiary, director and corporation, agent and principal, lawyer and client, doctor and patient, parent and child, and guardian and ward. Notwithstanding their variety, all fiduciary relationships are presumed to enjoy common characteristics and to attract a core set of demanding legal duties, most notably a duty of loyalty. Surprisingly, however, the justification for fiduciary duties is an enigma in private law theory. It is unclear what makes a relationship fiduciary and why fiduciary relationships attract fiduciary duties. This article takes up the enigma. It assesses leading reductivist and instrumentalist analyses of the justification for fiduciary duties. Finding them wanting, it offers an alternative account of the juridical justification for fiduciary duties. The author contends that the fiduciary relationship is a distinctive kind of legal relationship in which one person (the fiduciary) exercises power over practical interests of another (the beneficiary). Fiduciary power is a form of authority derived from the legal capacity of the beneficiary or a benefactor. The duty of loyalty is justified on the basis that it secures the exclusivity of the beneficiary's claim over fiduciary power so understood.
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115992.More information
In recent years there has been a remarkable convergence across several common law jurisdictions regarding the need to recognize some form of a tort of invasion of privacy, particularly with respect to the publication of private facts. Despite this convergence, the author argues that there remains a palpable “containment anxiety” at play in the jurisprudence that is responsible for a number of recurring tensions regarding the scope of protection.Instead of focusing on the question of how to define privacy, this paper frames the containment anxiety at issue in the cases in terms of a justificatory dilemma rather than a definitional one. Using the work of Mill and Kant, the author argues that if we understand privacy rights as protecting either the value of autonomy or freedom from harm then we can justify a narrow legal right to privacy. Although this can explain the containment anxiety in the jurisprudence, it severely undermines the growing recognition of the importance of privacy. Therefore this paper proposes an alternative justification for privacy rights that is rooted in the value of protecting identity interests, where identity is understood in terms of one's capacity for self-presentation.
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115993.More information
The Roma are the sole people in Europe (still) having a living customary law system. In this article, we intend to explore and to analyse the hypostases of the interaction between the customary law of the Roma in Romania and the Romanian law system. To do so, we will first briefly present the theoretical framework guiding our analytical demarche, namely normative pluralism. Then, we will present the main differences between the two legal orders in relation with the two modes of social and political organization. Finally, we will sketch and explore the three hypostases of the interaction between the Roma customary law and the Romanian state law — the official non-coplanarity, the marginal intersection and the exceptional subordination.
Keywords: Droit coutumier, droit étatique, communautés roms, Roumanie, hypostases de l'interaction, Customary law, state law, Roman communities, Romania, hypostases of interaction
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115994.More information
SummaryProminent writers in industrial relations (IR) have concluded the field is in significant decline, partly because of a failed theory base. The theory problem is deepened because other writers conclude developing a theory foundation for industrial relations is neither possible nor desirable. We believe advancing IR theory is both needed and possible, and take up the challenge in this paper.A long-standing problem in theorizing industrial relations has been the lack of agreement on the field's core analytical construct. However, in the last two decades writers have increasingly agreed the field is centred on the employment relationship. Another long-standing problem is that writers have theorized industrial relations using different theoretical frames of reference, including pluralist and radical-Marxist; different disciplinary perspectives, such as economics, sociology, history, and politics; and from different national traditions, such as British, French, and American.In this paper, we seek to advance IR theory and better integrate paradigms and national traditions. We do this by developing an analytical explanation for four core features of the employment relationship—generation of an economic surplus, cooperation-conflict dialectic, indeterminate nature of the employment contract, and asymmetric authority and power in the firm—using an integrative mix of ideas and concepts from the pluralist and radical-Marxist streams presented in a multi-part diagram constructed with marginalist tools from conventional economics. The diagram includes central IR system components, such as labour market, hierarchical firm, macro-economy, and nation state government. The model is used to explain the four features of the employment relationship and derive implications for IR theory and practice. Examples include the diagrammatic representation of the size and distribution of the economic surplus, a new analytical representation of labour exploitation, identification of labour supply conditions that encourage, respectively, cooperation versus conflict, and demonstration of how inequality of bargaining power in labour markets contributes to macroeconomic stagnation and unemployment.
Keywords: industrial relations theory, British-American industrial relations, pluralist-radical, employment relationship, cooperation and conflict, exploitation, théories des relations industrielles, relations industrielles anglo-américaines, courant pluraliste-radical, relation d'emploi, coopération et conflit, exploitation, teoría de las relaciones industriales, relaciones industriales británico-americanas, pluralismo radical, relaciones de empleo, cooperación y conflicto, explotación
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115995.More information
AbstractThis article which develops the theme of current topics of research in education is the result of a collaborative project among several experts in this area, and presents a description of the vast field in which educational researchers work, the methodological requirements related to the various research areas, and the important challenges which researchers confront. Research in the disciplines, in didactics, in pedagogy, in foundations and in practices, among other fields of research in education, co-exist and find a legitimate place in this arena. This article contributes both to defining the object of educational research and to enriching the debate and thinking about research practices.
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115996.More information
The mean interannual discharge of the River Amazon in the Atlantic Ocean has been estimated using two methods, independent but complementary. After having defined, in the most logical way, the eastern limit of the Amazon basin, the water balance from Óbidos was established for the 1972-2003 period. The mean interannual discharge at the mouth would be 205,000 m3•s-1. A second method was based on ten sets of flow measurements done at the mouth from 1997 to 2008, which correlated very well with the corresponding discharge values observed in Óbidos. This method indicates an interannual flow at the mouth of 208,000 m3•s-1, including 6,000 m3•s-1 that represent the derivation from the Amazon River towards Rio Pará (and the Ocean) by the furos, channels that run in the River Amazon's old arm. With an uncertainty of ± 6%, the interannual contributions of the River Amazon to the Ocean, over the 1972-2003 period, would be 206,000 m3•s-1, and would represent 17% of the total volume of fresh water entering the oceans worldwide.
Keywords: Hydrologie, Amazone, Débit, Statistique, Bilan hydrologique, Mesures, Amazon River, Discharge, Statistics, Water balance, Measurements
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115997.More information
A large number of models are available for streamflow forecasting. In this paper we classify and compare nine types of models for short, medium and long-term flow forecasting, according to six criteria: 1. validity of underlying hypotheses, 2. difficulties encountered when building and calibrating the model, 3. difficulties in computing the forecasts, 4. uncertainty modeling, 5. information required by each type of model, and 6. parameter updating. We first distinguish between empirical and conceptual models, the difference being that conceptual models correspond to simplified representations of the watershed, while empirical model only try to capture the structural relationships between inputs to the watershed and outputs, such as streamflow. Amongst empirical models, we distinguish between stochastic models, i.e. models based on the theory of probability, and non-stochastic models. Three types of stochastic models are presented: statistical regression models, Box-Jenkins models, and the nonparametric k-nearest neighbor method. Statistical linear regression is only applicable for long term forecasting (monthly flows, for example), since it requires independent and identically distributed observations. It is a simple method of forecasting, and its hypotheses can be validated a posteriori if sufficient data are available. Box-Jenkins models include linear autoregressive models (AR), linear moving average models (MA), linear autoregressive - moving average models (ARMA), periodic ARMA models (PARMA) and ARMA models with auxiliary inputs (ARMAX). They are more adapted for weekly or daily flow forecasting, since the yallow for the explicit modeling of time dependence. Efficient methods are available for designing the model and updating the parameters as more data become available. For both statistical linear regression and Box-Jenkins models, the inputs must be uncorrelated and linearly related to the output. Furthermore, the process must be stationary. When it is suspected that the inputs are correlated or have a nonlinear effect on the output, the k-nearest neighbor method may be considered. This data-based nonparametric approach simply consists in looking, among past observations of the process, for the k events which are most similar to the present situation. A forecast is then built from the flows which were observed for these k events. Obviously, this approach requires a large database and a stationary process. Furthermore, the time required to calibrate the model and compute the forecasts increases rapidly with the size of the database. A clear advantage of stochastic models is that forecast uncertainty may be quantified by constructing a confidence interval. Three types of non-stochastic empirical models are also discussed: artificial neural networks (ANN), fuzzy linear regression and multivariate adaptive regression splines (MARS). ANNs were originally designed as simple conceptual models of the brain. However, for forecasting purposes, these models can be thought of simply as a subset of non linear empirical models. In fact, the ANN model most commonly used in forecasting, a multi-layer feed-forward network, corresponds to a non linear autoregressive model (NAR). To capture the moving average components of a time series, it is necessary to use recurrent architectures. ANNs are difficult to design and calibrate, and the computation of forecasts is also complex. Fuzzy linear regression makes it possible to extract linear relationships from small data sets, with fewer hypotheses than statistical linear regression. It does not require the observations to be uncorrelated, nor does it ask for the error variance to be homogeneous. However, the model is very sensitive to outliers. Furthermore, a posteriori validation of the hypothesis of linearity is not possible for small data sets. MARS models are based on the hypothesis that time series are chaotic instead of stochastic. The main advantage of the method is its ability to model non-stationary processes. The approach is non-parametric, and therefore requires a large data set.Amongst conceptual models, we distinguish between physical models, hydraulic machines, and fuzzy rule-based systems. Most conceptual hydrologic models are hydraulic machines, in which the watershed is considered to behave like a network of reservoirs. Physical modeling of a watershed would imply using fundamental physical equations at a small scale, such as the law of conservation of mass. Given the complexity of a watershed, this can be done in practice only for water routing. Consequently, only short term flow forecasts can be obtained from a physical model, since the effects of precipitation, infiltration and evaporation must be negligible. Fuzzy rule-based systems make it possible to model the water cycle using fuzzy IF-THEN rules, such as IF it rains a lot in a short period of time, THEN there will be a large flow increase following the concentration time. Each fuzzy quantifier is modeled using a fuzzy number to take into account the uncertainty surrounding it. When sufficient data are available, the fuzzy quantifiers can be constructed from the data. In general, conceptual models require more effort to develop than empirical models. However, for exceptional events, conceptual models can often provide more realistic forecasts, since empirical models are not well suited for extrapolation.A fruitful approach is to combine conceptual and empirical models. One way of doing this, called extended streamflow prediction or ESP, is to combine a stochastic model for generating meteorological scenarios with a conceptual model of the watershed.Based on this review of flow forecasting models, we recommend for short term forecasting (hourly and daily flows) the use of the k-nearest neighbor method, Box-Jenkins models, water routing models or hydraulic machines. For medium term forecasting (weekly flows, for example), we recommend the k-nearest neighbor method and Box-Jenkins models, as well as fuzzy-rule based and ESP models. For long term forecasting (monthly flows), we recommend statistical and fuzzy regression, Box-Jenkins, MARS and ESP models. It is important to choose a type of model which is appropriate for the problem at hand and for which the information available is sufficient. Each type of model having its advantages, it can be more efficient to combine different approaches when forecasting streamflow.
Keywords: Revue, prévision, débit, modèle stochastique, modèle conceptuel, réseau de neurones artificiels, théorie des sous-ensembles flou, Review, forecasting, flow, stochastic model, conceptual model, artificial neural network, fuzzy set theory
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115998.More information
This study is dedicated to the review of the different technologies used and evaluated for the removal and/or recovery of metals from industrial effluents. The principles involved in these technologies are discussed, as well as the advantages and limits associated with these processes. The metal removal and recovery processes include the following techniques: precipitation, adsorption and biosorption, electrowinning and electrocoagulation, cementation, membrane separations, solvent extraction and ion exchange.Precipitation and coprecipitation are the most used and studied methods for metal removal from industrial waste waters. The method of precipitation used most often to remove metals from waste water consists of precipitating them in the form of hydroxides. The usual procedure involves the addition of chemicals such as lime (CaO or Ca(OH)2), Mg(OH)2, NaHCO3, Na2 CO3, (NH4)2 CO3, NaOH or NH4 OH. The precipitation of metals by carbonates or sulphides is an effective alternative to hydroxide precipitation. The use of carbonates allows the precipitation of metals to occur at pH values lower than those necessary with the hydroxides. Moreover, the precipitates thus formed are denser and have better characteristics of solid-liquid separation. Precipitation by sulphides is normally carried out with reagents such as: Na2 S, NaHS, H2 S or FeS. In acidic media, the lower solubility of metal sulphides (Cd, Co, Cu, Cr, Ni, Mn, Zn, etc.), makes it possible to reach concentrations lower than those obtained by precipitation as hydroxides. Coprecipitation with aluminum and iron salts is also an effective means for the removal of metals from effluents.Adsorption methods are also widely applied and examined for this purpose. However, in most cases the use of adsorbents requires an effluent neutralization step. Indeed, the neutralization of acid effluents must take place to allow their disposal in sewerage systems. A wide variety of adsorbents can be employed, both organic and inorganic: aluminum or iron oxides, sand, activated carbon, mixtures of coal and pyrite, iron particles, gravel or crushed brick, cement, etc. Studies have demonstrated the possibility of eliminating metals by adsorption on vegetable matter: peat moss, sawdust and wood bark, etc. Chitin and chitosan, two natural polymers that are abundant in the cell walls of fungi and shellfish, also have excellent properties of metal fixation. The utilization of different agricultural by-products (peanut skins, coconuts, corn cobs, onions skins, tea leaves, coffee powder, canola meal, etc.) for metal adsorption has also been proposed.Biosorption has been intensively studied in recent years as an economical treatment for metal recovery from dilute industrial effluents. Biosorption implies the use of live or dead biomass and/or their derivatives, which adsorb the metal ions with the ligands or functional groups located on the external surface of the microbial cells. Capacities for metal adsorption on various types of biomass (bacteria, yeasts, fungi, marine and freshwater algae) have been evaluated. The microorganisms used for the metal adsorption step must usually be immobilized in a matrix or in an easily recoverable support. The immobilizing agents or matrices most usually employed are alginate, polyacrylamine, polysulphone, silica gel, cellulose and glutaraldehyde.Electrowinning is a well-established technology that is widely employed in the mining and metallurgical industries (heap leaching, acid mine drainage, etc.), in metal transformation industries (wastes from plating and metal finishing), and in the electronics and electrical industries for the removal and/or the recovery of metals in solution. Many metals (Ag, Au, Cd, Co, Cr, Cu, Ni, Pb, Sn and Zn) present in the effluents can be recovered by electrodeposition using insoluble anodes.Electrocoagulation is another electrochemical approach, which uses an electrical current to remove several metals in solution. In fact, the electrocoagulation systems can be effective in removing suspended solids, dissolved metals, tannins and dyes. The contaminants present in waste water are maintained in solution by electrical charges. When these ions and the other charged particles are neutralized with ions of opposite electric charge, provided by a electrocoagulation system, they become destabilized and precipitate in a form that is usually very stable.Cementation is a type of precipitation method implying an electrochemical mechanism. In this process, a metal having a higher oxidation potential passes into solution (e.g., oxidation of metallic iron, Fe(0), to ferrous iron, Fe(II)) to replace a metal having a lower oxidation potential. Copper is the metal most frequently separated by cementation. However, the noble metals (Ag, Au and Pd), as well as As, Cd, Ga, Pb, Sb and Sn, can also be recovered in this manner.Reverse osmosis and electrodialysis are two processes using semipermeable membranes applicable to the recovery of metal ions. In electrodialysis, selective membranes (alternation of cation and anion membranes) fit between the electrodes in electrolytic cells. A continuous electrical current and the associated ion migrations, allow the recovery of metals. The techniques of membrane separation are very efficient for the treatment of dilute waste waters.The metallurgical industry has used solvent extraction for many years for a broad range of separations. This technique is employed today for the removal of soluble metals (Cd, Cr, Co, Cu, Ni, Mo, U, V, Zn, etc.) from waste water. Separation is carried out in contact with an immiscible organic phase to form salts or complex compounds, which give a favorable solubility distribution between the aqueous and organic phases. Various types of reagents can be used for the extraction: carboxylic acids, aliphatic or aromatic amines, amino acids, alkyl phosphates, phenolic compounds. The non-selective removal of metal contaminants in aqueous solutions can be obtained with a whole range of organic reagents. Promising new reagents have been proposed recently for the selective extraction of metals, such as Cd, Co, Cr and Zn.Ion exchangers are insoluble substances having in their molecular structure acidic or basic groups able to exchange, without modification of their physical structure, the positive or negative ions fixed at these groups. The first ion exchangers used were natural substances containing aluminosilicates (zeolites, clays, etc). Nowadays, the most-used ion exchangers are mainly organic in nature (resins). For the extraction of metals, the removal of cations in solution is usually done with the sulphonic acid group (-SO3- H+) of a polystyrene resin, or, with a chelating resin containing iminodiacetate functional groups. Ion exchange has recently received considerable attention for the separation and concentration of metals from waste water. These developments are especially applicable to the plating and metal transformation industries, for the removal of Cr, Co, Cu, Cd, Ni, Fe and Zn.The more sophisticated processes, such as electrowinning, solvent extraction, membrane separations and ion exchange, although frequently used in metallurgical processes, are less popular for wastewater treatment than are precipitation methods. Finally, recycling and optimal management of effluents constitutes an approach more and more widely applied by industries to satisfy new environmental regulations and laws.
Keywords: Métal, enlèvement, précipitation, adsorption, électrodéposition, cémentation, membranes, extraction par solvant, échange d'ions, biosorption, Metal, removal, precipitation, adsorption, electrowinning, cementation, membranes, solvent extraction, ion exchange, biosorption
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115999.More information
By randomizing the inputs to the deterministic Nash-Dooge linear reservoir cascade, linear stochastic conceptual response models suitable for small catchments are formulated as simple linear stochastic dynamical systems within the formalism of stochastic differential equations (SDE's). The system driving processes, rainfall and evapotranspiration losses, the latter regarded as a negative input, are modeled respectively as a compound Poisson process and a mean zero white Gaussian noise superposed on a deterministic mean. Elementary stochasticized Nash-Dooge cascades of n equal linear reservoirs and two reservoirs in parallel are given as potential models of surface and subsurface response. On consideration of recent discoveries concerning streamflow generation, a more conceptually plausible coarse-grained dynamical model of parallel quick and slow response regimes is developed by confining all evapotranspiration losses to the slow reservoir, modeling evapotranspiration fluctuations as mean zero colored Gaussian noise and rationalizing a linearized infiltration model dependent on slow regime outflow just prior to an event. In essence, the effort is directed towards generalizing the deterministic Nash-Dooge theory of the unit hydrograph to a linear stochastic theory of catchment response.
Keywords: Modèles stochastiques théoriques, équations différentielles stochastiques, modèles stochastiques en cascades, théories linéaire stochastique, Stochastic conceptual models, stochastic differential equations, stochastic linear cascade, linear stochastic theory
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116000.More information
Biological treatment was examined for production of biologically stable water, increase disinfectant stability, and reduced formation of disinfection by products. Monitoring of assimilable organic carbon (AOC) levels in the effluent of the Swimming River Treatment Plant (SRTP) showed that values >100 µg/L could be related to the occurrence of coliform bacteria in the distribution system. A treatment goal of <100 µg/L was established for biologically active treatment processes. Granular activated carbon (GAC) filters were found to support a larger bacterial population, and thus, provide better biological removal of AOC and total organic carton (TOC). All biologically active filters showed good performance relative to effluent turbidity levels, and headloss development. Preozonation of raw water increased AOC levels an average of 2.3 fold, and always increased filter effluent AOC levels relative to nonozonated water. Application of free chlorine to GAC filters did not inhibit biological activity. Application of chloramines to GAC filters showed a slight inhibitory affect relative to free chlorine. Effluent AOC levels averaged 82 µg/L at an EBCT of 5 min, and decreased to an average of 57 µg/L at 20 min EBCT. EBCT did affect TOC removals, with efficiencies averaging 29, 33, 42, and 51 % removal at EBCTs of 5, 10, 15 and 20 min, respectively. Trihalomethane formation potentials (THMFP) were related to TOC levels. Processes Chat decreased TOC levels also decreased THMFP. A preozonated GAC/sand filter (EBCT 10 min) achieved an annual average 54 % removal of THMFP precursors. Post disinfection of biologically treated effluents reduced HPC bacterial counts by 2-2.5log10. Post chlorination or chloramination of prechlorinated GAC/sand effluents resulted in a 20 %, or a 44 % (respectively) increase in AOC levels. Post disinfection of preozonated water resulted in small (<8%) AOC increases. Despite increases in AOC levels, prechlorinated water had lower AOC levels than preozonated water, even after post disinfection.
Keywords: Carbone organique assimilable, carbone organique total, filtration biologique, traitement de l'eau potable, carbone actif granuleux, filtration, désinfection, ozone, chlore, chloramine (amine chloré), redéveloppement des bactéries, Assimilable organic carbon, total organic carbon, biological filtration, potable water treatment, granular active carbon, filtration, disinfection, ozone, chlorine, chloramine, bacterial regrowth