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CAS researchers have made breakthrough progress in their genetic and gene functional analysis of important agro-  相似文献   

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This study extended the scope of previous findings in human–computer interaction research within the computers are social actors paradigm by showing that online users attribute perceptions of moral qualities to Websites and, further, that differential perceptions of morality affected the extent of persuasion. In an experiment (N = 138) that manipulated four morality conditions (universalist, relativist, egotistic, control) across worldview, a measured independent variable, users were asked to evaluate a Web site designed to aid them in making ethical decisions. Web sites offered four different types of ethical advice as participants contemplated cases involving ethical quandaries. Perceptions of the Web sites’ moral qualities varied depending on the type of advice given. Further, the Web sites’ perceived morality and participants’ worldview predicted credibility, persuasiveness, and attitudes toward the Web sites.  相似文献   

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A collection for Dracaenaplants was established re-cently at the Xishuang-banna Tropical Botanical Garden(XTBG), Chinese Academy of Sci-ences (CAS). It is the first of its kindin China. With an area of 1.4hectares, the collection was con-structed in two parts, one is for thecollection of native species, and theother is for introduced cultivatedspecies. All together 34 species withabout 460 plants both from Chinaand abroad have been collected andcultivated in this collection. The col-lec…  相似文献   

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We explore how a firm’s knowledge structure characteristics and market identity—as reflected in its position in the industry value chain and market status—influence knowledge-based alliance (KBA) formation. We propose that a firm’s propensity to form KBAs is affected by the congruence (or misalignment) between its knowledge structure characteristics (i.e., knowledge depth and scope) and the role it plays in the industry, as demanded by its position in the value chain. We further argue that while a firm’s market status can amplify the positive effect of the congruence, thereby enhancing a firm’s proclivity to form KBAs, being prominent can also hurt a firm when it faces a misalignment between its knowledge structure characteristics and externally induced expectations related to its value chain position. We validate our arguments using panel data on 1051 firm-year observations for 197 firms patenting in the global fuel cell industry for the period 1999–2009. By developing a richer understanding of the relationship between a firm’s knowledge-based resources and KBA formation, we answer the call for a better understanding of how and when firms can leverage their internal knowledge configurations to improve their proclivity to form alliances.  相似文献   

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The newly established Kavli Institute for Theoretical Physics China at CAS (KITPC-CAS) celebrated its formal opening with an inaugural symposium entitled Frontiers of  相似文献   

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Image and text matching bridges visual and textual modality differences and plays a considerable role in cross-modal retrieval. Much progress has been achieved through semantic representation and alignment. However, the distribution of multimedia data is severely unbalanced and contains many low-frequency occurrences, which are often ignored and cause performance degradation, i.e., the long-tail effect. In this work, we propose a novel rare-aware attention network (RAAN), which explores and exploits textual rare content for tackling the long-tail effect of image and text matching. Specifically, we first design a rare-aware mining module, which contains global prior information construction and rare fragment detector for modeling the characteristic of rare content. Then, the rare attention matching utilizes prior information as attention to guide the representation enhancement of rare content and introduces the rareness representation to strengthen the similarity calculation. Finally, we design prior information loss to optimize the model together with the triplet loss. We perform quantitative and qualitative experiments on two large-scale databases and achieve leading performance. In particular, we conduct 0-shot test for rare content and improve rSum by 21.0 and 41.5 on Flickr30K (155,000 image and text pairs) and MSCOCO (616,435 image and text pairs), demonstrating the effectiveness of the proposed method for the long-tail effect.  相似文献   

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In this paper, the approximation problem of T–S fuzzy linear singular system for a class of nonlinear singular system with derivative of input is considered and the nonlinear singular system has impulses. Consider a numerical example and a two-wheel drive robot, the T–S fuzzy singular systems are calculated for original system with derivative of input. According to solvability and steps of solving of the two examples, the results are extended to more generally nonlinear singular system with derivative of input. The theorem and algorithm that are given if input-state system is bounded impulse-free item and separable impulse item, it can be approximated by T–S fuzzy singular system with arbitrary accuracy. Finally, a numerical simulation is carried out to show the consistency with theoretical analysis and illustrate the effectiveness of approximation.  相似文献   

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This paper presents a continuous delivery/continuous verifiability (CD/CV) method for IoT dataflows in edge–fog–cloud. A CD model based on extraction, transformation, and load (ETL) mechanism as well as a directed acyclic graph (DAG) construction, enable end-users to create efficient schemes for the continuous verification and validation of the execution of applications in edge–fog–cloud infrastructures. This scheme also verifies and validates established execution sequences and the integrity of digital assets. CV model converts ETL and DAG into business model, smart contracts in a private blockchain for the automatic and transparent registration of transactions performed by each application in workflows/pipelines created by CD model without altering applications nor edge–fog–cloud workflows. This model ensures that IoT dataflows delivers verifiable information for organizations to conduct critical decision-making processes with certainty. A containerized parallelism model solves portability issues and reduces/compensates the overhead produced by CD/CV operations. We developed and implemented a prototype to create CD/CV schemes, which were evaluated in a case study where user mobility information is used to identify interest points, patterns, and maps. The experimental evaluation revealed the efficiency of CD/CV to register the transactions performed in IoT dataflows through edge–fog–cloud in a private blockchain network in comparison with state-of-art solutions.  相似文献   

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正The Circular Electron-Positron Colloder(CEPC)is a very exciting project,and I’ve been particularly struck by the progress over the past year.Last November at the international advisory committee meeting of CEPC,we advised Yifang to increase the radius of the machine to a hundred kilometers.It’s about twice the size they were originally thinking,but it seemed to us that a  相似文献   

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Drawing upon elaboration likelihood model (ELM) and espoused culture, this study predicts that eWOM reader's individualism–collectivism orientation (ICO) moderates eWOM antecedent factors’ effects on the perception of information credibility. 274 data were collected from two leading electronic word-of-mouth (eWOM) forums in China, the results confirm our prediction: eWOM reader's ICO positively moderates information sidedness’ effect on the perception of information credibility, it also negatively moderates the relationships between information consistency/information rating and information credibility. These findings validate the necessity and importance to consider readers’ espoused cultural differences in eWOM context.  相似文献   

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In information retrieval (IR), the improvement of the effectiveness often sacrifices the stability of an IR system. To evaluate the stability, many risk-sensitive metrics have been proposed. Since the theoretical limitations, the current works study the effectiveness and stability separately, and have not explored the effectiveness–stability tradeoff. In this paper, we propose a Bias–Variance Tradeoff Evaluation (BV-Test) framework, based on the bias–variance decomposition of the mean squared error, to measure the overall performance (considering both effectiveness and stability) and the tradeoff between effectiveness and stability of a system. In this framework, we define generalized bias–variance metrics, based on the Cranfield-style experiment set-up where the document collection is fixed (across topics) or the set-up where document collection is a sample (per-topic). Compared with risk-sensitive evaluation methods, our work not only measures the effectiveness–stability tradeoff of a system, but also effectively tracks the source of system instability. Experiments on TREC Ad-hoc track (1993–1999) and Web track (2010–2014) show a clear effectiveness–stability tradeoff across topics and per-topic, and topic grouping and max–min normalization can effectively reduce the bias–variance tradeoff. Experimental results on TREC Session track (2010–2012) also show that the query reformulation and increase of user data are beneficial to both effectiveness and stability simultaneously.  相似文献   

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This paper investigates the distributed chattering-free containment control problem for multiple Euler–Lagrange systems with general disturbances under a directed topology. It is considered that only a subset of the followers could receive the information of the multiple dynamic leaders. First, by combining a linear sliding surface with a nonsingular terminal sliding manifold, a distributed chattering-free asymptotic containment control method is proposed under the assumption that the upper bounds of the general disturbances are known. Further, based on the high-order sliding mode control technique, an improved distributed chattering-free finite-time containment control algorithm is developed. Besides, adaptive laws are designed to estimate the unknown upper bounds of the general disturbances. It is demonstrated that all the followers could converge into the convex hull spanned by the leaders under both proposed control algorithms by graph theory and Lyapunov theory. Numerical simulations and comparisons are provided to show the effectiveness of both algorithms.  相似文献   

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Distributed systems consist of interconnected, lower-dimensional subsystems. For such systems, distributed analysis and design present several advantages, such as modularity, easier analysis and design, and reduced computational complexity. A special case of distributed systems is when the subsystems are connected in a string. Applications include distributed process control, traffic and communication networks, irrigation systems, hydropower valleys, etc. By exploiting such a structure, in this paper, we propose conditions for the distributed stability analysis of Takagi–Sugeno fuzzy systems connected in a string. These conditions are also extended to observer and controller design and illustrated on numerical examples.  相似文献   

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