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21.
The goal of this paper is to show how modal logic may be conceived as recording the derived rules of a logical system in the system itself. This conception of modal logic was propounded by Dana Scott in the early seventies. Here, similar ideas are pursued in a context less classical than Scott's.First a family of propositional logical systems is considered, which is obtained by gradually adding structural rules to a variant of the nonassociative Lambek calculus. In this family one finds systems that correspond to the associative Lambek calculus, linear logic, relevant logics, BCK logic and intuitionistic logic. Above these basic systems, sequent systems parallel to the basic systems are constructed, which formalize various notions of derived rules for the basic systems. The deduction theorem is provable for the basic systems if, and only if, they are at least as strong as systems corresponding to linear logic, or BCK logic, depending on the language, and their deductive metalogic is not stronger than they are.However, though we do not always have the deduction theorem, we may always obtain a modal analogue of the deduction theorem for conservative modal extensions of the basic systems. Modal postulates which are necessary and sufficient for that are postulates of S4 plus modal postulates which mimic structural rules. For example, the modal postulates which Girard has recently considered in linear logic are necessary and sufficient for the modal analogue of the deduction theorem.All this may lead towards results about functional completeness in categories. When functional completeness, which is analogous to the deduction theorem, fails, we may perhaps envisage a modal analogue of functional completeness in a modal category, of which our original category is a full subcategory.  相似文献   
22.
Weighting model is the only valuation model of life cycle impact assessment(LCIA) profile now. It simplifies evaluation function into linear function, and makes the determination of weighting factor complicated. Therefore the valuation of LCIA profile is the most critical and controversial step in life cycle assessment(LCA). Development on valuation models, which are understood easily and accepted widely, is urgently needed in the field of LCA.The modeling approaches for the linear evaluation function were summed up. The modeling approaches for the nonlinear evaluation function were set up by function approximation theory, which include choosing preference products, forming preference data, establishing artificial neural network(ANN) and training ANN by preference data.By selecting 7 material products as preference product, experience was done with modeling approaches of the nonlinear evaluation function. The results show that the modeling approaches and valuation model of the nonlinear evaluation function are more practical than the weighting model.  相似文献   
23.
Soluble sugars are essential nutrients generally perceived as phagostimulants to most insects studied. However, tannins are known as digestibility reducers, hence deleterious to caterpillar development, and as deterrents as well. Previous work demonstrated that larvae of the polyphagous oblique-banded leafroller, Choristoneura rosaceana, performed better when reared on a control + 0.5% tannic acid diet than on the standard control diet and that larvae reared on a control + 5% glucose diet had slower development and reduced survival. This study was designed to elucidate the behavioral and neurophysiological components of the larval responses to tannic acid and glucose. C. rosaceana larvae were reared individually from the first to the sixth instar on one of four different artificial diets: (1) control; (2) control + 5% glucose; (3) control + 0.5% tannic acid; (4) control + 5% glucose + 0.5% tannic acid. After 14 days, larvae reared on the control + 5% glucose diet had not developed past the fourth instar, whereas a considerable proportion of larvae reared on the control + 0.5% tannic acid diet had already attained the pupal stage. Insects reared on the control or the control + 5% glucose + 0.5% tannic acid diet had intermediate development, with most larvae in the fifth instar. In addition, once the mid-sixth instar was reached, the feeding preferences to 25 and 300 mM glucose, 25 mM tannic acid, and 25 mM glucose + 25 mM tannic acid over water were assessed in two-choice tests. Feeding affected preference. Control-reared insects preferred feeding on treatments containing glucose and were not deterred by tannic acid. However, larvae that had been exposed to tannic acid during their development were deterred by tannic acid and their glucose discrimination was impaired. The sensitivity to glucose was also examined from neurophysiological recordings by stimulating the sugar-sensitive cell (cell 1) on the lateral styloconic sensillum of the maxillary galea with increasing concentrations of glucose (1, 10, 25, 50, 100, 200, 300, and 500 mM). We also determined whether tannic acid was phagostimulatory, since insects develop relatively quickly on a diet containing this compound, by testing 1 mM tannic acid, 1 mM tannic acid + 300 mM glucose, and 300 mM glucose on the lateral styloconic sensilla. The traces indicated that 1 mM tannic acid was not detected by any of the four chemosensory cells in these sensilla. The combination of tannic acid and glucose produced no spikes from the sugar-sensitive cell, whereas a prominent spike activity resulted with 300 mM glucose. We concluded that, although C. rosaceana larvae develop faster on a tannic acid diet, this compound is not a phagostimulant. The converse is true for glucose; i.e., it stimulates the sugar-sensitive cell in the lateral styloconica in a concentration-dependent fashion. Previous dietary experience changes the sensory and behavioral responses of C. rosaceana to glucose. Our findings imply that not all compounds that are phagostimulatory are necessarily beneficial to an insect's fitness. Therefore, developmental studies should be interpreted in conjunction with behavioral and physiological data.  相似文献   
24.
One of the fundamental tasks of targeted marketing is to elicit associations between customers and products. Based on the results from information retrieval and utility theory, this article proposes a unified framework of targeted marketing. The customer judgments of products are formally described by preference relations and the connections of customers and products are quantitatively measured by market value functions. Two marketing strategies, known as the customer‐oriented and product‐oriented marketing strategies, are investigated. Four marketing models are introduced and examined. They represent, respectively, the relationships between a group of customers and a group of products, between a group of customers and a single product, between a single customer and a group of products, and between a single customer and a single product. Linear and bilinear market value functions are suggested and studied. The required parameters of a market value function can be estimated by exploring three types of information, namely, customer profiles, product profiles, and transaction data. Experiments on a real‐world data set are performed to demonstrate the effectiveness of the proposed framework.  相似文献   
25.
Today's news readers can be easily overwhelmed by the numerous news articles online. To cope with information overload, online news media publishes timelines for continuously developing news topics. However, the timeline summary does not show the relationship of storylines, and is not intuitive for readers to comprehend the development of a complex news topic. In this paper, we study a novel problem of exploring the interactions of storylines in a news topic. An interaction of two storylines is signified by informative news events that play a key role in both storylines. Storyline interactions can indicate key phases of a news topic, and reveal the latent connections among various aspects of the story. We address the coherence between news articles which is not considered in traditional similarity-based methods, and discover salient storyline interactions to form a clear, global picture of the news topic. User preference can be naturally integrated into our method to generate query-specific results. Comprehensive experiments on ten news topics show the effectiveness of our method over alternative approaches.  相似文献   
26.
The condensed combustion products of two model propellants consisting of ammonium perchlorate, aluminum, nitramine, and an energetic binder were studied by a sampling method. One of the propellants contained HMX with a particle size D 10 ≈ 490 μm, and the other RDX with a particle size D 10 ≈ 380 μm. The particle-size distribution and the content of metallic aluminum in particles of condensed combustion products with a particle size of 1.2 μm to the maximum particle size in the pressure range of 0.1–6.5 MPa were determined with variation in the particle quenching distance from the burning surface to 100 mm. For agglomerates, dependences of the incompleteness of aluminum combustion on the residence time in the propellant flame were obtained. The RDX-based propellant is characterized by more severe agglomeration than the HMX-based propellant — the agglomerate size and mass are larger and the aluminum burnout proceeds more slowly. The ratio of the mass of the oxide accumulated on the agglomerates to the total mass of the oxide formed is determined. The agglomerate size is shown to be the main physical factor that governs the accumulation of the oxide on the burning agglomerate. __________ Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 4, pp. 78–92, July–August, 2006.  相似文献   
27.
在多属性群决策中, 针对每一个属性下决策者都有一个关于决策方案的乘法偏好关系的决策问题, 提出一种基于乘法偏好关系的群一致性偏差熵多属性群决策方法. 此方法考虑到不同属性下的决策者具有不同的权重, 并通过迭代运算可以达到群一致性水平, 从而得出最终的不同属性下决策者的权重; 同时, 可以利用偏差熵模型来求解属性权重, 利用这两个权重最终获得一个综合各方意见的群一致性乘法偏好关系. 最后通过算例分析验证了所提出方法的有效性.  相似文献   
28.
由于必然模态词□的引入,谓词模态逻辑的公式在一个可能世界中的真假值可能依赖于其可达的可能世界.在谓词模态逻辑中存在个体跨可能世界相等问题.针对这一问题,Lewis提出了对应物理论,并且在对应物理论中用对应物关系来表示个体跨可能世界相等.但是,当一个对象具有一个以上的对应物时,谓词模态逻辑中的跨可能世界相等关系无法与对应物关系建立一一对应.通过限制谓词模态逻辑中全称量词∀的范围,给出了一种公式分层的谓词模态逻辑.它是谓词模态逻辑的一个子逻辑,并且其语言与谓词模态逻辑的语言是相同的.但其公式是分层定义的,使得∀可以出现在□的范围内,并且□不能出现在∀的范围内.由于任意形如∀xφx)的表达式都不是该逻辑的公式,以量词开头的公式在一个可能世界w中的真假值只依赖于w,该逻辑避免了个体跨可能世界相等问题.给出了该逻辑的语言、语法和语义,并证明了该逻辑是可靠的和完备的.  相似文献   
29.
熊文涛  余胜平 《控制与决策》2014,29(9):1715-1718

针对带有间接偏好信息的多准则决策问题, 首先利用加性效用函数理论提出一种排序方法, 该方法通过构建一个简单的优化模型, 得到与间接偏好信息相容的各评价值的效用; 然后, 利用线性插值方法计算出剩下方案各评价值的效用, 进而得到所有方案的综合效用及排序; 最后, 通过实例验证了该方法的有效性和可行性.

  相似文献   
30.
混合偏好模型下的分布式理性秘密共享方案   总被引:1,自引:0,他引:1  
理性秘密共享方案通过扩展参与者的类型后具有更好的适应性,而现有方案中的共享秘密往往依赖于秘密分发者,但在某些特定环境中秘密分发者并不一定存在.通过对传统分布式秘密共享方案的分析,给出了分布式理性秘密共享方案的一般形式化描述;同时,考虑理性参与者的眼前利益和长远利益,提出一种新的理性参与者混合偏好模型;进一步结合机制设计理论的策略一致机制,设计了一个激励相容的信誉讨价还价机制,以此有效约束理性参与者的行为,从而实现了公平的(t,n)(t,n≥2)分布式理性秘密共享方案的构造;通过从信道类型、秘密分发者的在线/离线需求、方案的通用性和偏好模型等方面与目前相关理性秘密共享方案进行对比分析,进一步分析了所提出方案的优势.  相似文献   
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