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81.
Fusing multiple Bayesian knowledge sources   总被引:1,自引:0,他引:1  
We address the problem of information fusion in uncertain environments. Imagine there are multiple experts building probabilistic models of the same situation and we wish to aggregate the information they provide. There are several problems we may run into by naively merging the information from each. For example, the experts may disagree on the probability of a certain event or they may disagree on the direction of causality between two events (e.g., one thinks A causes B while another thinks B causes A). They may even disagree on the entire structure of dependencies among a set of variables in a probabilistic network. In our proposed solution to this problem, we represent the probabilistic models as Bayesian Knowledge Bases (BKBs) and propose an algorithm called Bayesian knowledge fusion that allows the fusion of multiple BKBs into a single BKB that retains the information from all input sources. This allows for easy aggregation and de-aggregation of information from multiple expert sources and facilitates multi-expert decision making by providing a framework in which all opinions can be preserved and reasoned over.  相似文献   
82.
Where vineyard exposure to bushfire smoke cannot be avoided or prevented, grape and wine producers need strategies to transform smoke-affected juice and wine into saleable product. This study evaluated the potential for spinning cone column (SCC) distillation to be used for the remediation of ‘smoke taint’. Compositional analysis of ‘stripped wine’ and condensate collected during SCC treatment of two smoke-tainted red wines indicated limited, if any, removal of volatile phenols, while their non-volatile glycoconjugates were concentrated due to water and ethanol removal. Together with the removal of desirable volatile aroma compounds, this enhanced the perception of smoke-related sensory attributes; i.e., smoke taint intensified. Stripped wines also became increasingly sour and salty as ethanol (and water) were progressively removed. A preliminary juice remediation trial yielded more promising results. While clarification, heating, evaporation, deionization and fermentation processes applied to smoke-tainted white juice gave ≤3 µg/L changes in volatile phenol concentrations, SCC distillation of smoke-tainted red juice increased the volatile phenol content of condensate (in some cases by 3- to 4-fold). Deionization of the resulting condensate removed 75 µg/L of volatile phenols, but fermentation of reconstituted juice increased volatile phenol concentrations again, presumably due to yeast metabolism of glycoconjugate precursors. Research findings suggest SCC distillation alone cannot remediate smoke taint, but used in combination with adsorbents, SCC may offer a novel remediation strategy, especially for tainted juice.  相似文献   
83.
Once the Cinderella amongst the Platinum Group Metals at the Photochemistry Ball, iridium has become of intense interest since the beginning of the decade. Complexes of iridium(III) can be prepared that are highly luminescent, with emission wavelengths tuneable over the whole of the visible region. Whilst most studies have focused on tris-bidentate complexes, a rich and varied chemistry is also possible using tridentate ligands. In this review, we discuss the synthesis and excited-state properties of such complexes, exploring in particular how the number of cyclometallating carbon atoms in the coordination sphere of the metal ion influences the luminescence. Moving from [IrN6]3+ to [IrN3X3] coordination via [IrN5X]2+ and cis/trans-[IrN4X2]+ complexes, where N is a heterocyclic nitrogen and X is an anionic ligand or cyclometallated carbon, a whole range of luminescence efficiencies are encountered, ranging from the barely detectable to room temperature quantum yields approaching unity. We consider the extent to which these profound differences, arising as a result of subtle changes in molecular structure, can be rationalised in terms of the nature of the frontier orbitals.  相似文献   
84.
Abstract— Results of a quantitative photochemical study of poly- p -benzoylphenylacetimido-bovine serum albumin in the presence of small-molecule triplet quenchers are reported. The efficiency of quenching by organic salts containing low triplet energy chromophores is shown to be qualitatively dependent on their predicted association constants to the modified protein. In addition, quenching is inhibited by salts of organic acids which possess high binding affinities for the protein but do not contain chromophores of low triplet energy. Quantitative treatment of the quenching and inhibition data yields results which strongly support the operation of an 'affinity controlled' mechanism for triplet energy transfer from the benzophenone moieties of the modified-bovine serum albumin to quenchers such as α-naphthylacetate and trans -cinnamate.  相似文献   
85.
The role of physical testing in product development is changing due to the requirements for faster new product development, reduced tolerance of failures in the field and the emergence of computer aided engineering (CAE) technologies. To be used most effectively, testing must be seen as an integral part of the process for reducing risks associated with new product introductions. Quality function deployment (QFD) and failure modes and effects analysis (FMEA) can be used to establish effective test and development plans that integrate the use of virtual and physical testing. By effectively integrating virtual and physical test technologies significant improvements in product performance can be achieved within shorter times and with reduced development and manufacturing costs. The approach was illustrated by a process of reducing in-cab noise during the design of a new truck.  相似文献   
86.
We discuss the absorption of electromagnetic radiation in small conducting particles, in the case where the electron motion is diffusive. We refine an earlier theory in which we calculated the absorption coefficient using an effective potential describing the screened electric field. Our new theory incorporates the effects of non-locality in the electrical conductivity, and shows how the two limiting behaviours of the effective potential at high and low frequencies can be derived from a unified theory. Our results are in full agreement with our earlier calculation. Received: 3 November 1997 / Accepted: 29 January 1998  相似文献   
87.
88.
Journal of the Operational Research Society -  相似文献   
89.
90.
从烟草(品种革新一号)单倍体花粉植株的叶和茎产生的愈伤组织,结合悬浮培养,获得的细胞分离出原生质体。在液体培养基中静置培养,12小时后原生质体开始变为卵圆形,细胞壁明显可见,24小时后完成第一次细胞分裂。以后继续分裂形成浅黄色的愈伤组织,在培养四星期后可达1毫米大小,再放到转床上进行旋转培养18天左右,愈伤组织可达3—4毫米大小。当转移到分化培养基后,分别分化出苗及根,长成完整的植株。 原生质体再生细胞的分裂与分化,不仅受不同器官来源的愈伤组织及其年龄的影响;还受分化培养基的基本成份及所用细胞分裂素的类型等的影响。  相似文献   
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