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301.
In most statistical machine translation (SMT) systems, bilingual segments are extracted via word alignment. However, there is a need for systematic study as to what alignment characteristics can benefit MT under specific experimental settings such as the type of MT system, the language pair or the type or size of the corpus. In this paper we perform, in each of these experimental settings, a statistical analysis of the data and study the sample correlation coefficients between a number of alignment or phrase table characteristics and variables such as the phrase table size, the number of untranslated words or the BLEU score. We report results for two different SMT systems (a phrase-based and an n-gram-based system) on Chinese-to-English FBIS and BTEC data, and Spanish-to-English European Parliament data. We find that the alignment characteristics which help in translation greatly depend on the MT system and on the corpus size. We give alignment hints to improve BLEU score, depending on the SMT system used and the type of corpus. For example, for phrase-based SMT, dense alignments are required with larger corpora, especially on the target side, while with smaller corpora, more precise, sparser alignments are better, especially on the source side. Avoiding some long-distance crossing links may also improve BLEU score with small corpora. We take these conclusions into account to modify two types of alignment systems, and get 1 to 1.6 % relative improvements in BLEU score on two held-out corpora, although the improved system is different in each corpus.  相似文献   
302.
The complexation of simple anions (F and Cl) to different neutral species, anion-coordinating agents, has been studied using electronic structure calculations. The obtained changes in the equilibrium constants for salt dissolution reactions in different typical electrolyte systems are reported. In addition the lithium ion affinities of the obtained anionic complexes have been calculated. Using the present results we discuss strategies for future usage of anion complexing agents and make recommendations of salt and agent combinations for better lithium battery electrolyte performance.  相似文献   
303.
Communication of emotions is of crucial importance in music performance. Yet research has suggested that this skill is neglected in music education. This article presents and evaluates a computer program that automatically analyzes music performances and provides feedback to musicians in order to enhance their communication of emotions. Thirty-six semiprofessional jazz/rock guitar players were randomly assigned to one of 3 conditions: (1) feedback from the computer program, (2) feedback from music teachers, and (3) repetition without feedback. Performance measures revealed the greatest improvement in communication accuracy for the computer program, but usability measures indicated that certain aspects of the program could be improved. Implications for music education are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
304.
In the present investigation, experimental measurements of the thermodynamic activities of iron oxide in the Al2O3‐“FeO”, CaO‐“FeO” and “FeO”‐SiO2 systems were performed in the temperature range 1823‐1873 K by using gas equilibration technique. The molten slag, kept in a Pt‐crucible was brought to equilibrium with a gas mixture of known oxygen partial pressure. A part of the Fe from the “FeO” was reduced during the equilibration and got dissolved in the Pt phase. The samples were quenched after the required equilibration time and the slag phase as well as the platinum crucible was subjected to chemical analysis. The activities of “FeO” in the slag were calculated from the experimental data using thermodynamic information on the Fe‐Pt binary metallic system generated and assessed earlier. The experimental results are compared with earlier thermodynamic studies of the slag systems. Reassessment with the KTH slag model is performed and the results are compared with other thermodynamic models, viz. F*A*C*T? and Thermo‐Calc? respectively. The experimental activities predicted by the KTH slag model are in good agreement with the experimental data available in the literature. A general agreement between the various models is also observed.  相似文献   
305.
Here, a Sb‐doped SnO2 (ATO) nanorod underneath an α‐Fe2O3 nanorod sheathed with TiO2 for photoelectrochemical (PEC) water splitting is reported. The experimental results, corroborated with theoretical analysis, demonstrate that the ATO nanorod underlayer effect on the α‐Fe2O3 nanorod sheathed with TiO2 enhances the PEC water splitting performance. The growth of the well‐defined ATO nanorods is reported as a conductive underlayer to improve α‐Fe2O3 PEC water oxidation performance. The α‐Fe2O3 nanorods grown on the ATO nanorods exhibit improved performance for PEC water oxidation compared to α‐Fe2O3 grown on flat fluorine‐doped tin oxide glass. Furthermore, a simple and facile TiCl4 chemical treatment further introduces TiO2 passivation layer formation on the α‐Fe2O3 to reduce surface recombination. As a result, these unique nanostructures show dramatically improved photocurrent density (139% higher than that of the pure hematite nanorods).  相似文献   
306.
When developing large-scale software systems, there is often a large amount of requirements present, and they often reside on several hierarchical levels. In most cases, not all stated requirements can be implemented into the product due to different constraints, and the requirements must hence be prioritized. As requirements on different abstraction levels shall not be compared, prioritization techniques that are able to handle multi-level prioritization are needed. Different such techniques exist, but they seem to result in unfair comparisons when a hierarchy is unbalanced. In this paper, an empirical experiment is presented where an approach that compensate for this challenge is evaluated. The results indicate that some form of compensation is preferred, and that the subjects’ preference is not influenced by the amount of information given.  相似文献   
307.
308.
因为扎哈·哈迪德事务繁忙,所以这次采访只有作为扎哈·哈迪德建筑师事务所合伙人的帕特里克·舒马赫出席。同时任教于伦敦AA建筑学院的帕特里克是近些年非常活跃的年轻建筑师之一,他的写作对于哈迪德的实践有着推波助澜的作用。这是一次轻松的访谈,概括性地谈论一些建筑复杂性的现象,简述指导实践的概念与理论,有助于读者真正理解扎哈·哈迪德设计的形式,知其所以然。  相似文献   
309.
This paper analyzes the political economy of establishing bilateral trade in green certificate markets as one step towards harmonization of European green electricity support systems. We outline some of the economic principles of an integrated bilateral green certificates market, and then discuss a number of issues that are deemed to be critical for the effectiveness, stability and legitimacy of such a market. By drawing on some of the lessons of the fairly recent intentions to integrate a future green certificate market in Norway with the existing Swedish one, we highlight, exemplify and discuss some critical policy implementation and design issues. These include, for instance, the system's connection to climate policy targets, the role of other support schemes and the definition of what green electricity technologies should be included. Furthermore, the establishment of an international market presumes that the benefits of renewable power (e.g., its impacts on the environment, diversification of the power mix, self-sufficiency, etc.) are approached and valued from an international perspective rather than from a national one, thus implying lesser emphasis on, for instance, employment and regional development impacts. A bilateral green certificate system thus faces a number of important policy challenges, but at the same time it could provide important institutional learning effects that can be useful for future attempts aiming at achieving greater policy integration in the European renewable energy sector.  相似文献   
310.
The most extensive action targeting the adoption of energy efficiency measures in small- and medium-sized manufacturing industries in Sweden over the past 15 years was project Highland. This paper presents an evaluation of the first part of this local industrial energy programme, which shows an adoption rate of more than 40% when both measures that have already been implemented and measures that are planned to be implemented are included. A comparison between this programme and another major ongoing programme for the Swedish energy-intensive industry indicates that the approach used in project Highland aimed at small- and medium-sized industries is an effective way to increase energy efficiency in the Swedish industry. The major barriers to energy efficiency among the firms were related to the low priority of the energy efficiency issue.  相似文献   
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