A high-aspect-ratio microchannel heat exchanger based on multi-tool milling process was developed. Several slotting cutters were stacked together for simultaneously machining several high-aspect-ratio microchannels wi...A high-aspect-ratio microchannel heat exchanger based on multi-tool milling process was developed. Several slotting cutters were stacked together for simultaneously machining several high-aspect-ratio microchannels with manifold structures. On the basis of multi-tool milling process, the structural design of the manifold side height, microchannel length, width, number, and interval were analyzed. The heat transfer performances of high-aspect-ratio microchannel heat exchangers with two different manifolds were investigated by experiments, and the influencing factors were analyzed. The results indicate that the magnitude of heat transfer area per unit volume dominates the heat transfer performances of plate-type micro heat exchanger, while the velocity distribution between microchannels has little effects on the heat transfer performances.展开更多
属性级情感分析作为一种细粒度情感分析方法,目前在许多应用场景中都具有重要作用.然而,随着社交媒体和在线评论的日益广泛以及各类新兴领域的出现,使得跨领域属性级情感分析面临着标签数据不足以及源领域与目标领域文本分布差异等挑战...属性级情感分析作为一种细粒度情感分析方法,目前在许多应用场景中都具有重要作用.然而,随着社交媒体和在线评论的日益广泛以及各类新兴领域的出现,使得跨领域属性级情感分析面临着标签数据不足以及源领域与目标领域文本分布差异等挑战.目前已有许多数据增强方法试图解决这些问题,但现有方法生成的文本仍存在语义不连贯、结构单一以及特征与源领域过于趋同等问题.为了克服这些问题,提出一种基于大语言模型(large language model,LLM)数据增强的跨领域属性级情感分析方法.所提方法利用大模型丰富的语言知识,合理构建针对跨领域属性级别情感分析任务的引导语句,挖掘目标领域与源领域相似文本,通过上下文学习的方式,使用领域关联关键词引导LLM生成目标领域有标签文本数据,用以解决目标领域数据缺乏以及领域特异性问题,从而有效提高跨领域属性级情感分析的准确性和鲁棒性.所提方法在多个真实数据集中进行实验,实验结果表明,该方法可以有效提升基线模型在跨领域属性级情感分析中的表现.展开更多
In machine translation(MT) practice,there is an urgent need for constructing a set of Chinese-to-English aspect transferring rules to define the transferring conditions.The integrated feature set was used to generaliz...In machine translation(MT) practice,there is an urgent need for constructing a set of Chinese-to-English aspect transferring rules to define the transferring conditions.The integrated feature set was used to generalize and justify the Chinese-to-English transferring rule of the 'ZHE' aspect(ZHE Rule).A ZHE classification model was built in this study.The impacts of each set of temporal,lexical aspectual,and syntactic features,and their integrated impacts,on the accuracy of the ZHE Rule were tested.Over 600 misclassified corpus sentences were manually examined.A 10-fold cross-validation was used with a decision tree algorithm.The main results are:(1) The ZHE Rule was generalized and justified to have a higher accuracy under the two metrics:the precision rate and the areas under the receiver operating characteristic curve(AUC).(2) The temporal,lexical aspectual,and syntactic feature sets have an integrated contribution to the accuracy of the ZHE Rule.The syntactic and temporal features have an impact on ZHE aspect derivations,while the lexical aspectual features are not predictive of ZHE aspect derivation.(3) While associated with active verbs,the ZHE aspect can denote a perfective situation.This study suggests that the temporal and syntactic features are the predictive ZHE aspect classification features and that the ZHE Rule with an overall precision rate of 80.1% is accurate enough to be further explored in MT practice.The machine learning method,decision tree,can be applied to the automatic aspect transferring in MT research and aspectual interpretations in linguistic research.展开更多
基金Projects(50675070 50805052) supported by the National Nature Science Foundation of China+1 种基金Projects(07118064 8451064101000320) supported by the Natural Science Foundation of Guangdong Province
文摘A high-aspect-ratio microchannel heat exchanger based on multi-tool milling process was developed. Several slotting cutters were stacked together for simultaneously machining several high-aspect-ratio microchannels with manifold structures. On the basis of multi-tool milling process, the structural design of the manifold side height, microchannel length, width, number, and interval were analyzed. The heat transfer performances of high-aspect-ratio microchannel heat exchangers with two different manifolds were investigated by experiments, and the influencing factors were analyzed. The results indicate that the magnitude of heat transfer area per unit volume dominates the heat transfer performances of plate-type micro heat exchanger, while the velocity distribution between microchannels has little effects on the heat transfer performances.
文摘属性级情感分析作为一种细粒度情感分析方法,目前在许多应用场景中都具有重要作用.然而,随着社交媒体和在线评论的日益广泛以及各类新兴领域的出现,使得跨领域属性级情感分析面临着标签数据不足以及源领域与目标领域文本分布差异等挑战.目前已有许多数据增强方法试图解决这些问题,但现有方法生成的文本仍存在语义不连贯、结构单一以及特征与源领域过于趋同等问题.为了克服这些问题,提出一种基于大语言模型(large language model,LLM)数据增强的跨领域属性级情感分析方法.所提方法利用大模型丰富的语言知识,合理构建针对跨领域属性级别情感分析任务的引导语句,挖掘目标领域与源领域相似文本,通过上下文学习的方式,使用领域关联关键词引导LLM生成目标领域有标签文本数据,用以解决目标领域数据缺乏以及领域特异性问题,从而有效提高跨领域属性级情感分析的准确性和鲁棒性.所提方法在多个真实数据集中进行实验,实验结果表明,该方法可以有效提升基线模型在跨领域属性级情感分析中的表现.
基金supported by the National Social Science Foundation of China(No.08BYY001)the Worldwide Universities Network 2009 Research Mobility Programme
文摘In machine translation(MT) practice,there is an urgent need for constructing a set of Chinese-to-English aspect transferring rules to define the transferring conditions.The integrated feature set was used to generalize and justify the Chinese-to-English transferring rule of the 'ZHE' aspect(ZHE Rule).A ZHE classification model was built in this study.The impacts of each set of temporal,lexical aspectual,and syntactic features,and their integrated impacts,on the accuracy of the ZHE Rule were tested.Over 600 misclassified corpus sentences were manually examined.A 10-fold cross-validation was used with a decision tree algorithm.The main results are:(1) The ZHE Rule was generalized and justified to have a higher accuracy under the two metrics:the precision rate and the areas under the receiver operating characteristic curve(AUC).(2) The temporal,lexical aspectual,and syntactic feature sets have an integrated contribution to the accuracy of the ZHE Rule.The syntactic and temporal features have an impact on ZHE aspect derivations,while the lexical aspectual features are not predictive of ZHE aspect derivation.(3) While associated with active verbs,the ZHE aspect can denote a perfective situation.This study suggests that the temporal and syntactic features are the predictive ZHE aspect classification features and that the ZHE Rule with an overall precision rate of 80.1% is accurate enough to be further explored in MT practice.The machine learning method,decision tree,can be applied to the automatic aspect transferring in MT research and aspectual interpretations in linguistic research.
