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41.
An algorithmic procedure is devised for loading and releasing work to a job shop environment. The objective of the procedure is the control and balance of workloads in the shop. The importance of shop balance is justified and several measures of performance are derived. Comparative results are given to illustrate the effects of proper control on various shop statistics. 相似文献
42.
We considered the effects of plant secondary metabolites on the immune response, a key physiological defense of herbivores
against pathogens and parasitoids. We tested the effect of host plant species and ingested iridoid glycosides on the immune
response of the grazing, polyphagous caterpillar, Grammia incorrupta (Arctiidae). Individuals of G. incorrupta were fed either one of three plant diets with varying secondary metabolites, or an artificial diet with high or low concentrations
of iridoid glycosides. An immune challenge was presented, followed by measurement of the encapsulation response. We failed
to detect a significant difference in the immune response of G. incorrupta feeding on diets with varying concentrations of iridoid glycosides, or feeding on different host plants. However, the immune
response was lower in caterpillars consuming the artificial diet compared to those consuming the plant diets. When caterpillar
performance was measured, pupal weights were lower when caterpillars ingested high concentrations of iridoid glycosides due
to a decrease in feeding efficiency. Overall, individuals of G. incorrupta that consumed different plant diets exhibited a high immune response with low variation. We conclude that the immune response
of G. incorrupta is adapted to feeding on a variety of plants, which may contribute to the maintenance of this caterpillar’s polyphagous habit. 相似文献
43.
J. H. B. Deane D. J. Jefferies 《International Journal of Circuit Theory and Applications》1990,18(2):175-187
The one-dimensional full return map for the repetitively triggered monostable multivibrator is derived analytically and some of its properties under iteration by computer are investigated. It is found that the monostable can exhibit periodic, intermittent and chaotic behaviour as the triggering frequency is varied. the predictions of the theory are verified experimentally, suggesting that such methods may be used with confidence as a design tool. 相似文献
44.
45.
Amy M. Trowbridge M. Deane Bowers Russell K. Monson 《Journal of chemical ecology》2016,42(12):1281-1292
Changes in the chemical composition of plant defense compounds during herbivory can impact herbivore resource allocation patterns and thereby herbivore survival, growth, and immune response against endoparasitoid infection. Few studies have investigated folivore responses to changes in plant chemistry that occur under outbreak conditions in mature conifer systems. Using data from an earlier observational field study, we carried out laboratory bioassays to test how variation in monoterpenes in piñon pine trees (Pinus edulis, Pinaceae) during an outbreak affects growth, consumption, and immune response of a specialist herbivore, the Southwestern tiger moth (Lophocampa ingens, Arctiidae). Larvae were fed on artificial diets containing four monoterpenes at concentrations that mimicked those observed in undamaged and herbivore-damaged trees in situ during an outbreak. Damaged trees contained 30% lower total monoterpene concentrations, likely reflecting volatile losses as observed in a previous field study Trowbridge et al. (Ecology 95:1591–1603, Trowbridge et al. 2014). Herbivores reared on diets mimicking terpene concentrations in the needles of damaged trees exhibited an approximately 60% increase in consumption relative to larvae reared on diets characteristic of trees without herbivore damage. Higher consumption was accompanied by a 40% increase in immune response with no change in growth rate. These observations suggest preferential resource allocation towards immunity and/or a strong genetic component that determines growth under these conditions. These outcomes, which favor the herbivore, point to: (i) a potential positive feedback mechanism that may increase L. ingens’s chance of escaping parasitism during the early phases of an outbreak; and (ii) the important role of monoterpenes in mediating conifer-folivore interactions specifically for P. edulis, which has suffered large-scale drought-induced mortality events exacerbated by the presence of insects. 相似文献
46.
Shapiro Deane H. Jr.; Schwartz Carolyn E.; Astin John A. 《Canadian Metallurgical Quarterly》1996,51(12):1213
This article begins by examining psychology's contributions to understanding the positive consequences of control for individual mental and physical health. Person-environment control mismatches and the negative personal, interpersonal, and societal consequences of seeking and having control are then discussed. As corrections to mismatches and negative consequences, three methods of analyses are provided. First, definitional and conceptual precision is offered, including a more careful matching of control-related interventions to multidimensional, individual-specific control profiles. Second, therapeutic assessment and interventions are placed within a biopsychosocial model of control. Finally, philosophy of science and paradigmatic issues underlying control theories are highlighted, particularly as they affect psychology's role in examining values toward which control efforts should be directed. These topics are important for people's personal and collective well-being. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Supporting security and adequacy in future energy systems: The need to enhance long‐term energy system models to better treat issues related to variability
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Manuel Welsch Mark Howells Mohammad Reza Hesamzadeh Brian Ó Gallachóir Paul Deane Neil Strachan Morgan Bazilian Daniel M. Kammen Lawrence Jones Goran Strbac Holger Rogner 《国际能源研究杂志》2015,39(3):377-396
As the shares of variable renewable generation in power systems increase, so does the need for, inter alia, flexible balancing mechanisms. These mechanisms help ensure the reliable operation of the electricity system by compensating for fluctuations in supply or demand. However, a focus on short‐term balancing is sometimes neglected when assessing future capacity expansions with long‐term energy system models. Developing heuristics that can simulate short‐term system issues is one way of augmenting the functionality of such models. To this end, we present an extended functionality to the Open Source Energy Modelling System (OSeMOSYS), which captures the impacts of short‐term variability of supply and demand on system adequacy and security. Specifically, we modelled the system adequacy as the share of wind energy is increased. Further, we enable the modelling of operating reserve capacities required for balancing services. The dynamics introduced through these model enhancements are presented in an application case study. This application indicates that introducing short‐term constraints in long‐term energy models may considerably influence the dispatch of power plants, capacity investments, and, ultimately, the policy recommendations derived from such models. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
48.
Polonsky Ira; Fox Ronald E.; Wiens Arthur N.; Dixon Theodore R.; Freedman Mervin B.; Shapiro Deane H. Jr. 《Canadian Metallurgical Quarterly》1979,34(4):339
Six professional psychologists join in an invited interaction of models, modes, and standards of professional training in psychology. The first represents California Psychologists Concerned with Professional Standards, a group questioning "the proliferation of institutions in California offering the doctoral degree in psychology outside the framework of any established set of professional guidelines"; the second represents a university-based professional school of psychology not in California; the third is a member of the American Psychological Association's Accreditation Committee; the final three represent professional schools of psychology in California. (5 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
Instability, subharmonics, and chaos in power electronic systems 总被引:12,自引:0,他引:12
The concept of chaos is applied to a variety of nonlinear power electronic circuits. With the onset of instability, the phenomena of subharmonics, quasi-periodicity, and chaos are predicted and observed. The following examples are dealt with: diodes with charge storage (with application to resonant converters); a ferroresonant circuit; a controlled thyristor rectifier circuit; and a Buck converter controlled by pulse-width modulation (PWM). The examples were chosen to model aspects of real power electronic systems. Analytical and experimental results demonstrate the complex nonlinear phenomena such as subharmonics, quasi-periodicity and chaos can arise in even the simplest systems 相似文献
50.
The purpose of this study was to investigate the effect of acid conditioning of root surfaces during recombinant human bone morphogenetic protein-2 (rhBMP-2) induced periodontal regeneration in vivo. The buccal aspect of molar roots were denuded of their periodontal ligament through a bony window created in the mandible of 34 Wistar rats under general anesthesia. Three groups of 11 or 12 animals received either 10 microL of 50 g/mL rhBMP-2 in a collagen gel over the surgical defect (BMP) or 10 microL of collagen gel only (COL) or were left untreated (UN). Each of the 3 groups were further subdivided into those that received prior root acid conditioning with 35% phosphoric acid gel and those without acid conditioning. Animals were sacrificed 10 days after surgery and the tissues processed for histological examination. The BMP groups with and without acid conditioning developed significantly more bone over the second molar (3.89+/-0.86% and 7.62+/-0.93%, respectively; mean+/-SE), compared with the respective COL (1.24+/-0.26% and 2.77+/-0.52%) and UN groups (1.34+/-0.35% and 3.69+/-0.37%) (P <0.05). Furthermore, significantly more bone was found in the BMP non-acid conditioned group compared with all other groups (P <0.05). Acid conditioning promoted significantly more ankylosis (50%) compared with non-acid conditioning (6.3%) (P=0.007). New cementum formation was greatest in the BMP acid conditioned group (628.4+/-253.8 microm2) and lowest in the non-acid conditioned UN group (207.6+/-36.4 microm2) (P <0.05). This is the first known report evaluating the effects of root acid conditioning after a single application of rhBMP-2 in vivo. Results suggest that root conditioning agents operating at low pH administered into the periodontal wound impairs early BMP-induced osteogenesis while simultaneously promoting BMP-induced cementogenesis. 相似文献