438 research outputs found

    Bibliography of Sequential Sampling Plans in Insect Pest Management Based on Wald\u27s Sequential Probability Ratio Test

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    This paper contains 65 references dealing with the development of sequential sampling plans in insect pest management based on Wald\u27s Sequential Probability Ratio Test (SPRT), 25 in forest entomology and 40 in agriculture entomology. The insect(s) sampled, whether the decision procedure was based on one or two SPRTs, and the mathematical distribution and probabilities of Type I and Type II errors used to develop the SPRTs are also given for each sequential sampling plan

    Development of Empirical Models to Rate Spruce-Fir Stands in Michigan\u27s Upper Peninsula for Hazard From the Spruce Budworm (Lepidoptera: Tortricidae): A Case History

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    The procedure used to develop empirical models which estimate potential spruce budworm impact to spruce-fir stands in Michigan\u27s Upper Peninsula is reviewed. Criteria used to select independent variables, to select the best of alternative multiple linear regression models. and to validate final models are discussed. Preliminary, intermediate, and final results demonstrate a cyclic pattern to the development procedure. Validation is emphasized as an important step in the procedure. Implications of using the hazard-rating system as a pest management tool in the stand management process are discussed

    Experimental units for the beginning teacher of Spanish in the intermediate grades of Stanislaus County schools

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    The increasing emphasis on foreign language learning in the elementary school is the reason for the study to develop experimental units for the beginning teacher of Spanish in the intermediate grades of Stanislaus County schools

    Kinetics of the ferric sulphate leaching of sphalerite and sphalerite/pyrite mixtures : a study of the chemical leaching of base metal minerals under conditions similar to that of bio-leaching by thiobacilli

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    Bibliography: pages 98-105.The work presented in this dissertation is an investigation of-the ferric leaching of zinc from sphalerite. A further aspect of this study was an investigation of the influence of pyrite on the dissolution rate of sphalerite due to possible galvanic interactions. This study is one component of a larger study of the sub-processes involved in the bioleaching of sulphide minerals in which the ferric leaching of the sulphide mineral is assumed to be a chemical step with the bacteria oxidising ferrous iron to ferric iron and elemental sulphur, if formed, to sulphate. The literature showed that two types of model have been used to describe the ferric leaching of the sphalerite. The first type was a shrinking-particle model in which there action was described by first order kinetics or an electrochemical mechanism. The second type included a mass transfer resistance in terms of a shrinking-core model described by half-order kinetics or a decaying diffusion coefficient. All four of these models were tested for their ability to predict published data for the ferric leaching of sphalerite. It was found that the models fitted the data for the initial period of a leach up to conversions of about 50%. However, no one of the models was found to be successful in predicting the data for prolonged leaching to high conversions

    Acquisition of syntax in a minature artificial language : effects of input and instruction

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    Metadata merged with duplicate record (http://hdl.handle.net/10026.1/568) on 20.12.2016 by CS (TIS).This is a digitised version of a thesis that was deposited in the University Library. If you are the author please contact PEARL Admin ([email protected]) to discuss options.The goal of the research was to discover which type of input and instruction best facilitates the acquisition of syntax in adult learners. An artificial miniature language was used to model real second language to control precisely the type of input, conditions of exposure and instruction accompanying that input. Performance of learners under four input conditions was compared and analogies were drawn between these conditions and those experienced by adult second language learners (L2 learners). "Instructed" learners Z): like formally instructed L2 learners were systematically taught the rules of the language. "Exposure" learners saw example sentences and were asked to search for rules, the conditions of their input analogous to that of "naturalistic" L2 learners who receive no formal instruction but who make conscious efforts to search for rules. "Memorisation" learners received the same input as that presented to the exposure learners but were asked to memorise the sentencesT. hey were seena s analogoust o naturalistic L2 learners who do not search for the rules and the conditions of input were modelled on those claimed to induce implicit learning. "Cued" learners received input which contained cross-sentential cues to underlying phrasal structure. They were modelled on naturalistic learners whose input contains such cues and who make efforts to search for rules. Performance was compared on both grammaticality judgement and free production tasks. No overall superiority in performance was observed for any of the input conditions. An interaction between input type and rule complexity was evident in which the amount of information received regarding the rules related positively to performance on. the less salient, more complex rules. It was proposed that the findings could be explained in terms of a "noticing" hypothesis, in which noticing of features is considered a pre-requisite for acquisition. Theories of second and artificial language learning which have stipulated that complex rules can only be learned implicitly were not supported

    Secure Database Access and Transfer Using Public Key Cryptography

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    Nowadays many transactions on internet are implemented by security mechanisms.so authentication plays a vital role in securing data, not only in a single process but with varioustransactions.Many security initiatives are defensive strategiesâ€â€aimed at pro tectingthe perimeter of the network. But these works may ignore a crucial Things sensitive data stored on networked servers are at risk from attackers who only need to find one way inside the network to access this confidential information. Additionally, perimeter defenseslike firewalls cannot protect stored sensitive data from the internal threatâ€â€employees with the means to access and exploit this data.Encryption can provide strong security for data at rest, but developing a database encryption strategy must take many factors into consideration.RSA is a rather mature public key algorithm in that itcan be used to encrypt and sign. This paper examines the issues of implementing access and transferring the data using public key cryptog raphy

    Reproductive performance of the marine green porcelain crab \u3ci\u3ePetrolisthes armatus\u3c/i\u3e Gibbes, 1850 in its introduced range favors further range expansion

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    Invasive marine crustaceans can exhibit population-level variation in reproductive traits that are consistent with a response to stressful conditions near the range edge, or alternatively, that may favor establishing new exotic populations. Reproductive characteristics of the green porcelain crab Petrolisthes armatus Gibbes, 1850 were not previously known in its invasive range in the Atlantic waters of the southeastern USA. We compared fecundity estimates, size at sexual maturity, and various other morphological aspects among crabs collected from two sites at each of four locations spanning approximately 230 km from North Inlet, South Carolina (SC), to Savannah, Georgia (GA), USA. Reproductive output and smallest ovigerous female sizes within the invaded range also were compared to those in the native range, which extends from the Gulf of Mexico and the Caribbean to Brazil in the Western Atlantic Ocean. Reproductive output and egg number were higher and female size at maturity was smaller for crabs from more northern locations (North Inlet and Charleston, SC). Crabs were sexually dimorphic, but population-level differences in overall morphology (e.g., dimensions of the carapace, chelipeds, and secondary sexual characteristics) were not evident in two populations examined (North Inlet, SC, and Bluffton, SC). Secondary sexual characteristics (i.e., abdomen length, abdomen width and pleopod length) contributed the most to the morphological differences between males and females. Using allometric methods, size at sexual maturity was estimated to be 3.99 mm carapace width (CW) for males at North Inlet and 2.96 mm CW for males at Bluffton. Minimum sizes of ovigerous females at our study sites were smaller (3.0 mm to 4.2 mm CW) than a published value for a native population (4.0 mm CW). Reproductive output also was higher in the introduced range (0.05–0.11) than in native populations (0.03–0.07). Along a latitudinal gradient at the northern extent of the invaded range, females allocated more energy to producing offspring at range-edge locations. These results indicate that both within the introduced range and compared to the native range, P. armatus exhibits considerable variation in reproductive performance, which may have assisted in the species′ successful invasion and may aid the species in continuing its range expansion

    Development of Empirical Models to Rate Spruce-Fir Stands in Michigan\u27s Upper Peninsula for Hazard From the Spruce Budworm (Lepidoptera: Tortricidae): A Case History

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    The procedure used to develop empirical models which estimate potential spruce budworm impact to spruce-fir stands in Michigan\u27s Upper Peninsula is reviewed. Criteria used to select independent variables, to select the best of alternative multiple linear regression models. and to validate final models are discussed. Preliminary, intermediate, and final results demonstrate a cyclic pattern to the development procedure. Validation is emphasized as an important step in the procedure. Implications of using the hazard-rating system as a pest management tool in the stand management process are discussed
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