909 resultados para Sandalow, Terrance, 1934-
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The first report of the disease (“pine wilt disease”) associated with the pinewood nematode, goes back to 1905, when Yano reported an unusual decline of pines from Nagasaki. For a long time thereafter, the cause of he disease was sought, but without success. Because of the large number of insect species that were usually seen around and on infected trees, it had always been assumed that the causal agent would prove to be one of these. However, in 1971, Kiyohara and Tokushike found a nematode of the genus Bursaphelenchus in infected trees. The nematode found was multiplied on fungal culture, inoculated into healthy trees and then re-isolated from the resulting wilted trees. The subsequent published reports were impressive: this Bursaphelenchus species could kill fully-grown trees within a few months in the warmer areas of Japan, and could destroy complete forests of susceptible pine species within a few years. Pinus densiflora, P. thunbergii und P. luchuensis were particularly affected. In 1972, Mamiya and Kiyohara described the new species of nematode extracted from the wood of diseased pines; it was a named Bursaphelenchus lignicolus. Since 1975, the species has spread to the north of Japan, with the exception of the most northerly prefectures. In 1977, the loss of wood in the west of the country reached 80%. Probably as a result of unusually high summer temperatures and reduced rainfall in the years 1978 and 1979, the losses were more than 2 million m3 per year. From the beginning, B. lignicolus was always considered by Japanese scientists to be an exotic pest. But where did it come from? That this nematode could also cause damage in the USA became clear in 1979 when B. lignicolus was isolated in great numbers from wood of a 39 year-old pine tree (Pinus nigra) in Missouri which had suddenly died after the colour of its needles changed to a reddish-brown colour (Dropkin und Foudin, 2 1979). In 1981, B. lignicolus was synonymised by Nickle et al. with B. xylophilus which had been found for the first time in the USA as far back as 1929, and reported by Steiner and Buhrer in 1934. It had originally been named Aphelenchoides xylophilus, the wood-inhabiting Aphelenchoides but was recognised by Nickle, in 1970,to belong in the genus Bursaphelenchus. Its common name in the USA was the "pine wood nematode" (PWN. After its detection in Missouri, it became known that B. xylophilus was widespread throughout the USA and Canada. It occurred there on native species of conifers where, as a rule, it did not show the symptoms of pine wilt disease unless susceptible species were stressed eg., by high temperature. This fact was an illuminating piece of evidence that North America could be the homeland of PWN. Dwinell (1993) later reported the presence of B. xylophilus in Mexico. The main vector of the PWN in Japan was shown to be the long-horned beetle Monochamus alternatus, belonging to the family Cerambycidae. This beetle lays its eggs in dead or dying trees where the developing larvae then feed in the cambium layer. It was already known in Japan in the 19th century but in the 1930s, it was said to be present in most areas of Japan, but was generally uncommon. However, with the spread of the pine wilt disease, and the resulting increase of weakened trees that could act as breeding sites for beetles, the populations of Monochamus spp. increased significantly In North America, other Monochamus species transmit PWN, and the main vector is M. carolinensis. In Japan, there are also other, less efficient vectors in the genus Monochamus. Possibly, all Monochamus species that breed in conifers can transmit the PWN. The occasional transmission by less efficient species of Monochamus or by some of the many other beetle genera in the bark or wood is of little significance. In Europe, M. galloprovincialis and M. sutor transmits the closely related species B. mucronatus. Some speculate that these two insect species are “standing by” and waiting for the arrival of B. xylophilus. In 1982, the nematode was detected and China. It was first found in dead pines near the Zhongshan Monument of Nanjing (CHENG et. al. 1983); 265 trees were then killed by pine wilt disease. Despite great efforts at eradication in China, the nematode spread further and pine wilt disease has been 3 reported from parts of the provinces of Jiangsu, Anhui, Guangdong, Shandong, Zhejiang and Hubei (YANG, 2003). In 1986, the spread of the PWN to Taiwan was discovered and in 1989, the nematode was reported to be present in the Republic of Korea where it had first been detected in Pinus thunbergii and P. densiflora. It was though to have been introduced with packing material from Japan. PWN was advancing. In 1984, B. xylophilus was found in wood chips imported into Finland from the USA and Canada, and this was the impetus to establish phytosanitary measures to prevent any possible spread into Europe. Finland prohibited the import of coniferous wood chips from these sources, and the other Nordic countries soon followed suit. EPPO (the European and Mediterranean Plant Protection Organization) made a recommendation to its member countries in 1986 to refuse wood imports from infested countries. With its Directive of 1989 (77/93 EEC), the European Community (later called the European Union or EU) recognised the potential danger of B. xylophilus for European forests and imposed restrictions on imports into the Europe. PWN was placed on the quarantine list of the EU and also of other European countries. Later, in 1991, a dispensation was allowed by the Commission of the EU(92/13 EEC) for coniferous wood from North America provided that certain specified requirements were fulfilled that would prevent introduction.
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Le Bulletin des agriculteurs existe depuis 1918 et a eu une incidence considérable sur la population rurale du Québec.Le présent mémoire porte sur la subversion dans douze récits fantastiques publiés dans la revue entre 1940 et 1959. Ce mémoire est divisé en trois chapitres distincts.Le premier relate la petite histoire de la revue. À ses débuts, en 1918,Le Bulletin des agriculteurs est une revue purement agricole qui n'a d'autre but que celui d'informer ses abonnés. Mais dès 1936, la revue adopte le style revue et apporte à ses nombreux lecteurs, en plus de l'information générale, des chroniques féminines, des articles humoristiques et des récits de fiction. Ce sont ces derniers qui sont à l'origine de ce mémoire.Le deuxième chapitre insistera sur l'aspect théorique de l'étude. Dans un premier temps, nous avons fait la typologie de tous les récits de fiction parus dans la revue entre 1934 et 1984 les classant par genre et par sous-genre. Dans un deuxième temps, nous avons étudié le fantastique et son potentiel subversif. Enfin, dans un troisième temps, nous avons identifié l'idéologie qui prévalait au Québec rural dans les années quarante et cinquante.Le troisième chapitre est consacré exclusivement à la recherche de subversion dans les douze contes fantastiques sélectionnés afin d'en faire une lecture sociocritique.
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This document contains a speech by John L. McLaurin, representative of South Carolina. Sections of the speech include: sectionalism exposed, the bill might have been defeated, the south plundered of its rights, not a protectionist, fraudulent demands of New England, Hon. Randolph Tucker, Hon. W.R. Morrison, and Hon. R.Q. Mills strangers to the doctrine in 1882, a tariff for revenue against the doctrine of free raw material, don’t want Cleveland’s interpretation, contest of schedules, and my remedy.
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This document contains a speech by John L. McLaurin of South Carolina presented in the Senate of the United States. Sections of the speech include: sectionalism the cause, conditions in South Carolina, the federal administration in South Carolina, should not array class against class, freedom of thought and speech, the issues, under caucus dictation the Senate no longer a deliberative body, the beginning of the fight, matter of arraying class against class, freedom of thought and speech, and issues.
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This document contains a speech of John L. McLaurin, representative of South Carolina, in the House of Representatives on Tuesday, March 23, 1897 about proposed tariffs.
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This speech is to address the statement that Mr. McLaurin has been excluded from the caucuses of his party and thus that he will be without assignment on any committee. He goes on to explain his exclusion and defend his views that led to his exclusion.
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In response to contemporary concerns, and using neglected primary sources, this article explores the professionalisation of teachers of Religious Education (RI/RE) in non-denominational, state-maintained schools in England. It does so from the launch of Religion in Education (1934) and the Institute for Christian Education at Home and Abroad (1935) to the founding of the Religious Education Council of England and Wales (1973) and the British Journal of Religious Education (1978). Professionalisation is defined as a collective historical process in terms of three inter-related concepts: (1) professional self-organisation and professional politics, (2) professional knowledge, and (3) initial and continuing professional development. The article sketches the history of non-denominational religious education prior to the focus period, to contextualise the emergence of the professionalising processes under scrutiny. Professional self-organisation and professional politics are explored by reconstructing the origins and history of the Institute of Christian Education at Home and Abroad, which became the principal body offering professional development provision for RI/RE teachers for some fifty years. Professional knowledge is discussed in relation to the content of Religion in Education which was oriented around Christian Idealism and interdenominational networking. Changes in journal name in the 1960s and 1970s reflected uncertainties about the orientation of the subject and shifts in understanding over the nature and character of professional knowledge. The article also explores a particular case of resistance, in the late 1960s, to the prevailing consensus surrounding the nature and purpose of RI/RE, and the representativeness and authority of the pre-eminent professional body of the time. In conclusion, the article examines some implications which may be drawn from this history for the prospects and problems of the professionalisation of RE today.
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A simple but effective technique to improve the performance of the Max-Log-MAP algorithm is to scale the extrinsic information exchanged between two MAP decoders. A comprehensive analysis of the selection of the scaling factors according to channel conditions and decoding iterations is presented in this paper. Choosing a constant scaling factor for all SNRs and iterations is compared with the best scaling factor selection for changing channel conditions and decoding iterations. It is observed that a constant scaling factor for all channel conditions and decoding iterations is the best solution and provides a 0.2-0.4 dB gain over the standard Max- Log-MAP algorithm. Therefore, a constant scaling factor should be chosen for the best compromise.
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The renowned writer J. B. Priestley suggested in 1934 that the motor-coach had annihilated the old distinction between rich and poor passengers in Britain. This article considers how true this was by examining the relationship between charabancs, motor coaches and class. It shows that this important vehicle of inter-war working class mobility had a complicated relationship with class, identifying three distinct forms of this method of travel. It positions the charabanc alongside historical responses to unwelcome steamer and railway day-trippers, and examines how resorts provided separate class-based entertainment for these holidaymakers. Using the case study of a new charabancwelcoming pub, the Prospect Inn, it proposes that, in the late 1930s, some pubs were beginning to offer charabanc customers facilities that were almost the match of their middle class equivalent. Motor coaches and charabancs contributed to the process of social convergence in inter-war Britain.
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Power systems have been suffering huge changes mainly due to the substantial increase of distributed generation and to the operation in competitive environments. Virtual power players can aggregate a diversity of players, namely generators and consumers, and a diversity of energy resources, including electricity generation based on several technologies, storage and demand response. Resource management gains an increasing relevance in this competitive context, while demand side active role provides managers with increased demand elasticity. This makes demand response use more interesting and flexible, giving rise to a wide range of new opportunities.This paper proposes a methodology for managing demand response programs in the scope of virtual power players. The proposed method is based on the calculation of locational marginal prices (LMP). The evaluation of the impact of using demand response specific programs on the LMP value supports the manager decision concerning demand response use. The proposed method has been computationally implemented and its application is illustrated in this paper using a 32 bus network with intensive use of distributed generation.
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The introduction of Electric Vehicles (EVs) together with the implementation of smart grids will raise new challenges to power system operators. This paper proposes a demand response program for electric vehicle users which provides the network operator with another useful resource that consists in reducing vehicles charging necessities. This demand response program enables vehicle users to get some profit by agreeing to reduce their travel necessities and minimum battery level requirements on a given period. To support network operator actions, the amount of demand response usage can be estimated using data mining techniques applied to a database containing a large set of operation scenarios. The paper includes a case study based on simulated operation scenarios that consider different operation conditions, e.g. available renewable generation, and considering a diversity of distributed resources and electric vehicles with vehicle-to-grid capacity and demand response capacity in a 33 bus distribution network.
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In recent years, power systems have experienced many changes in their paradigm. The introduction of new players in the management of distributed generation leads to the decentralization of control and decision-making, so that each player is able to play in the market environment. In the new context, it will be very relevant that aggregator players allow midsize, small and micro players to act in a competitive environment. In order to achieve their objectives, virtual power players and single players are required to optimize their energy resource management process. To achieve this, it is essential to have financial resources capable of providing access to appropriate decision support tools. As small players have difficulties in having access to such tools, it is necessary that these players can benefit from alternative methodologies to support their decisions. This paper presents a methodology, based on Artificial Neural Networks (ANN), and intended to support smaller players. In this case the present methodology uses a training set that is created using energy resource scheduling solutions obtained using a mixed-integer linear programming (MIP) approach as the reference optimization methodology. The trained network is used to obtain locational marginal prices in a distribution network. The main goal of the paper is to verify the accuracy of the ANN based approach. Moreover, the use of a single ANN is compared with the use of two or more ANN to forecast the locational marginal price.
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Smart Grids (SGs) appeared as the new paradigm for power system management and operation, being designed to integrate large amounts of distributed energy resources. This new paradigm requires a more efficient Energy Resource Management (ERM) and, simultaneously, makes this a more complex problem, due to the intensive use of distributed energy resources (DER), such as distributed generation, active consumers with demand response contracts, and storage units. This paper presents a methodology to address the energy resource scheduling, considering an intensive use of distributed generation and demand response contracts. A case study of a 30 kV real distribution network, including a substation with 6 feeders and 937 buses, is used to demonstrate the effectiveness of the proposed methodology. This network is managed by six virtual power players (VPP) with capability to manage the DER and the distribution network.
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We study the effects of product differentiation in a Stackelberg model with demand uncertainty for the first mover. We do an ex-ante and ex-post analysis of the profits of the leader and of the follower firms in terms of product differentiation and of the demand uncertainty. We show that even with small uncertainty about the demand, the follower firm can achieve greater profits than the leader, if their products are sufficiently differentiated. We also compute the probability of the second firm having higher profit than the leading firm, subsequently showing the advantages and disadvantages of being either the leader or the follower firm.
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Dissertação apresentada para obtenção do Grau de Mestre de Bolonha em Ensino da Matemática pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia