在這一篇論文中我們討論的是下列這個非線性初值問題： u''(t)=u'(t)^q(c_1+c_2u(t)^p) u(0) = u_0; u'(0) = u_1: 我們關注於上述問題正解的一些性質。我們發現了一些爆破(Blow-up)現象，並獲得一些結果，有關爆破率(Blow-up rate)、爆破常數(Blow-up constant)以及爆破時間(Blow-up time)。 / In this paper we study the following initial value problem for the nonlinear equation, u''(t)=u'(t)^q(c_1+c_2u(t)^p) u(0) = u_0; u'(0) = u_1: We are interested in properties of positive solutions of the above problem.We have found blow-up phenomena and obtained some results on blowup rates, blow-up constants and life-spans.

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The air transport markets affected by global economic climate and regional demand characteristics are evolving fairly dynamically. To cope with the evolving demand and to penetrate desired market segments, operators' usage of aircraft has been getting more and more dynamic with increased deviation from the originally designed mission objectives. The objective of this research is to investigate the effects of in-service rrusslon variation on aircraft structural performance so as to provide airlines with a more realistic approach toward better fleet management. During the research, the scenarios and phenomena causing fleet in-service mission variations were investigated. A survey on the utilisation of world-wide aircraft fleets was conducted and presented. The in-service missions of aircraft fleets were found to vary significantly in terms of mission profile. Furthermore, the utilisation patterns of individual aircraft in the same fleet of a major airline are also being thoroughly analysed. Tremendous variations of mission mixes are found among individual aircraft. In order to analyse the effects of the in-service mission variation, methodologies and models based on fatigue test results have been developed by the author. Actual service data are being input for the effect analysis. It is found that the mission variation has a considerable engineering influence on the aircraft's structural performance either in terms of mission airworthiness or fatigue life span. Finally, a conceptual model, the 'Integrated Airline Fleet Management Model' (IAFM), has been developed as a blueprint for practical application. By implementing the IAFM, airline will be able to obtain a realistic picture of the health of its aircraft. With a more reliable basis for maintenance planning, improved inspection accuracy, reduced maintenance cost and better structural airworthiness can be achieved.

Thesis (Psy. D.)--Wheaton College Graduate School, 2007. / Abstract. Includes bibliographical references (leaves 35-40).

Thesis--University of Wisconsin--Madison. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 64-66).

Thesis (Psy. D.)--Wheaton College Graduate School, 2007. / Abstract. Includes bibliographical references (leaves 35-40).

Abstract Branches of adult Scots pine (Pinus sylvestris L.) trees were sampled from boreal dry pine forests to study needle longevity, its variation and its relation to other shoot characteristics. The stands studied were located along transects from two smelters and one city, e.g. along gradients of pollution impact. Constant needle age structures were assumed and static life-tables generated. Mean needle longevity was calculated as the sum of the proportions of living needle fascicles on the successive annual shoots. It fully incorporated the information of the static life-tables and was preferred to median or maximum ages because of its significantly lower variation. The first half of the shedding span, the duration of the period when the needle survival gradually dropped from 90 to 50 %, proved to validly reflect the changes in the needle age structure. Needle longevity decreased 15-40 % towards the pollution sources along the transects studied. Near the smelters, needle longevity decreased with the increasing needle Fe, or Fe, Ni and Cu concentration that represented the main constituents of the airborne particle emissions. Near the city, needle longevity decreased with the increasing needle N and P concentrations, annual needle mass and needle mass packing and decreasing needle area packing. In the urban forests, needle Mg, P and K concentrations decreased linearly with the decreasing needle survival from the second to the fourth needle age class. Concentrations in the living needles of the fourth age class stayed over 80 % of the average for all the age classes, though needle survival dropped below 50 %. A decreasing needle Mn concentration was detected towards all the emission sources. Leaching, especially from the soil, as a possible cause was discussed. Needle longevity had the lowest variation among the shoot characteristics, which increases its value as a tool in ecological monitoring. Low plasticity in needle longevity could be an acclimation to the ambient environmental conditions and length of the growing season and to maximise the carbon gain per time. Needle longevity decreased and annual needle mass and leaf mass per area increased upwards in the crowns of mature Scots pines, reflecting the acclimation to irradiance.

The life span of facilities produced by the Architecture-Engineering-Construction industry is typically 25 years or more Several distinct phases characterize the life span of a facility. Each of these phases involve numerous participants from different professional disciplines. These participants generate and use a lot of information about the facility. Current methods used by the industry to convey this information are drawings and specifications. However. these drawings and specifications reflect only a summary of the information generated and used by the project participants This summarized information only describes the product. Information about the process of generating these information becomes implicit in the drawings and specifications. Rationale is the collective term for this set of implicit process information. The main issue addressed by this dissertation is the need to communicate design rationale information. Design rationale is a subset of the entire rationale generated for a facility Design rationale refers to information about the design process. Explicitly stating design rationale information reduces the chance of misinterpreting design drawings and specifications. The primary objective of this dissertation is to determine a data structure capable of representing design rationale information. This data structure also allows a computer system to perform analytical tasks on the design rationale data. Examples of analytical tasks a computer system can perform on design rationale data include: generating a parameter dependency network and resolving data conflicts. This dissertation defines this data structure as two separate but complementary modules. The Knowledge Representation Module assists in gathering project-specific product information. The Rationale Storage Module assists in capturing project-specific process information. This dissertation discusses each of these two modules in detail. The secondary objectives of this dissertation include: (1) defining a computer program architecture, (2) creating a computer program interface, and (3) verifying the appropriateness of the data structure in representing design rationale. A proof-of-concept computer program, DRIVE, applied to an actual value engineering study project accomplishes these objectives. / Ph. D.

Insecticidal proteins from Bacillus thuringiensis (Bt) are used widely in sprays and transgenic plants to control insect pests. Although much research has elucidated the effects of Bt toxins on larvae, relatively little is known about their effects on adults. Here, we evaluated the effects of exposing adults to Bt toxin Cry1Ac on the life span and reproduction of two strains of pink bollworm (Pectinophora gossypiella (Saunders)). In larval diet bioassays, the concentration of Cry1Ac killing 50% of larvae (LC50) was 640 times higher for the laboratory-selected resistant strain (AZP-R) than the susceptible strain (APHIS-S). In experiments with adults, the highest concentrations of Cry1Ac tested (160 and 640 mu g Cry1Ac per ml of 5% honey water) reduced life span for both strains. Treatments with 10, 40, and 160 mg Cry1Ac per ml reduced the duration of the oviposition period as well as the number of eggs laid by both strains, but did not affect the percentage of pairs producing eggs, the duration of the preoviposition period, or the percentage of eggs hatching for either strain. Adult life span did not differ between strains at low to moderate concentrations of Cry1Ac, but it was significantly greater for the resistant strain than the susceptible strain at the two highest concentrations of Cry1Ac tested. The reduced susceptibility to high concentrations of Cry1Ac in adults of the AZP-R strain relative to the APHIS-S strain provides the first evidence of expression of resistance to a Bt toxin in adult Lepidoptera.