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1.
Repeated reference creates strong expectations in addressees that a speaker will continue to use the same expression for the same object. The authors investigate the root reason for these expectations by comparing a cooperativeness-based account (Grice, 1975) with a simpler consistency-based account. In two eye-tracking experiments, the authors investigated the expectations underlying the effect of precedents on comprehension. The authors show that listeners expect speakers to be consistent in their use of expressions even when these expectations cannot be motivated by the assumption of cooperativeness. The authors conclude that though this phenomenon seems to be motivated by cooperativeness, listeners' expectation that speakers be consistent in their use of expressions is governed by a general expectation of consistency. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Sharona Khier Sandra Tolchinsky Gerardo Z. Lederkremer Boaz Shaanan 《Israel journal of chemistry》1994,34(2):177-184
A model for the carbohydrate recognition domain (CRD) and combining site of the human asialoglycoprotein (ASGP) receptor has been computed on the basis of the close sequence homology with the mannose-binding lectin (MBP), whose three-dimensional structure in complex with a ligand has been determined by crystallographic methods (Weis, W.I.; Drickamer, K.; Hendrickson, W.A. Nature 1992, 360: 127). Within the limitations of modeling methods, the model is compatible with data on ligand binding of the family C-type lectins, of which the MBP and the ASGP receptor are members. The model derived can serve as a guide for designing site-directed mutagenesis experiments in order to further elucidate the origins of specificity of the ASGP receptor toward galactose. In particular, the model focuses attention on the possible role of position 207 (MBP sequence numbering) in promoting galactose binding. 相似文献
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A major problem in using iterative number generators of the form xi=f(xi−1) is that they can enter unexpectedly short cycles. This is hard to analyze when the generator is designed, hard to detect in real time when the generator is used, and can have devastating cryptanalytic implications. In this paper we define a measure of security, called sequence diversity, which generalizes the notion of cycle-length for noniterative generators. We then introduce the class of counter-assisted generators and show how to turn any iterative generator (even a bad one designed or seeded by an adversary) into a counter-assisted generator with a provably high diversity, without reducing the quality of generators which are already cryptographically strong. 相似文献
5.
Moshe P. Mann Boaz Zion Itzhak Shmulevich Dror Rubinstein Raphael Linker 《Journal of Intelligent and Robotic Systems》2016,82(3-4):399-411
A mobile melon robotic harvester consisting of multiple Cartesian manipulators, each with three degrees of freedom, is being developed. In order to design an optimal robot in terms of number of arms, manipulator capabilities, and robot speed, a method of allocating the fruits to be picked by each manipulator in a way that yields the maximum harvest has been developed. Such a method has already been devised for a multi-arm robot with 2DOF each. The maximum robotic harvesting problem was shown there to be an example of the maximum k-colorable subgraph problem (MKCSP) on an interval graph. However, for manipulators with 3DOF, the additional longitudinal motion results in variable intervals. To overcome this issue, we devise a new model based on the color-dependent interval graph (CDIG). This enables the harvest by multiple robotic arms to be modeled as a modified version of the MKCSP. Based on previous research, we develop a greedy algorithm that solves the problem in polynomial time, and prove its optimality using induction. As with the multi-arm 2DOF robot, when simulated numerous times on a field of randomly distributed fruits, the algorithm yields a nearly identical percentage of fruit harvested for given robot parameters. The results of the probabilistic analysis developed for the 2DOF robot was modified to yield a formula for the expected harvest ratio of the 3DOF robot. The significance of this method is that it enables selecting the most efficient actuators, number of manipulators, and robot forward velocity for maximal robotic fruit harvest. 相似文献
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The paper focuses on mining clusters that are characterized by a lagged relationship between the data objects. We call such
clusters lagged co-clusters. A lagged co-cluster of a matrix is a submatrix determined by a subset of rows and their corresponding lag over a subset
of columns. Extracting such subsets may reveal an underlying governing regulatory mechanism. Such a regulatory mechanism is
quite common in real-life settings. It appears in a variety of fields: meteorology, seismic activity, stock market behavior,
neuronal brain activity, river flow, and navigation, but a limited list of examples. Mining such lagged co-clusters not only
helps in understanding the relationship between objects in the domain, but assists in forecasting their future behavior. For
most interesting variants of this problem, finding an optimal lagged co-cluster is NP-complete problem. We present a polynomial-time
Monte-Carlo algorithm for mining lagged co-clusters. We prove that, with fixed probability, the algorithm mines a lagged co-cluster
which encompasses the optimal lagged co-cluster by a maximum 2 ratio columns overhead and completely no rows overhead. Moreover,
the algorithm handles noise, anti-correlations, missing values, and overlapping patterns. The algorithm is extensively evaluated
using both artificial and real-world test environments. The first enable the evaluation of specific, isolated properties of
the algorithm. The latter (river flow and topographic data) enable the evaluation of the algorithm to efficiently mine relevant
and coherent lagged co-clusters in environments that are temporal, i.e., time reading data and non-temporal. 相似文献
9.
One of the most fascinating properties of materials in nature is the superhydrophobic and self‐cleaning capabilities of different plant surfaces. This is usually achieved by the hydrophobic cuticles that are made of cutin and contain wax crystals both within them and on their surfaces. Here, bioinspired n‐hexatriacontane wax films are deposited via thermal evaporation and it is shown that the surface evolves in time via self‐assembly. This leads to a dramatic change in the wetting properties with a transition from hydrophobic to superhydrophobic characteristics, which takes place within several days at room temperature. This phenomenon is investigated and strain‐induced recrystallization is proposed to be the mechanism for it. This work could become the basis for the inspiration and production of tuned, time‐dependant, temperature‐sensitive, variable‐wettability surfaces. 相似文献
10.
H. Anyanzwa J. R. Okalebo C. O. Othieno A. Bationo B. S. Waswa J. Kihara 《Nutrient Cycling in Agroecosystems》2010,88(1):39-47
The effects of conservation tillage, crop residue and cropping systems on the changes in soil organic matter (SOM) and overall
maize–legume production were investigated in western Kenya. The experiment was a split-split plot design with three replicates
with crop residue management as main plots, cropping systems as sub-plots and nutrient levels as sub-sub plots. Nitrogen was
applied in each treatment at two rates (0 and 60 kg N ha−1). Phosphorus was applied at 60 kg P/ha in all plots except two intercropped plots. Inorganic fertilizer (N and P) showed
significant effects on yields with plots receiving 60 kg P ha−1 + 60 kg N ha−1 giving higher yields of 5.23 t ha−1 compared to control plots whose yields were as low as 1.8 t ha−1 during the third season. Crop residues had an additive effect on crop production, soil organic carbon and soil total nitrogen.
Crop rotation gave higher yields hence an attractive option to farmers. Long-term studies are needed to show the effects of
crop residue, cropping systems and nutrient input on sustainability of SOM and crop productivity. 相似文献