Phrase-Level Sentiment Polarity Classification Using Rule-Based Typed Dependencies and Additional Complex Phrases Consideration

The advent of Web 2.0 has led to an increase in user-generated content on the Web. This has provided an extensive collection of free-style texts with opinion expressions that could influence the decisions and actions of their readers. Providers of such content exert a certain level of influence on the receivers and this is evident from blog sites having effect on their readers＇ purchase decisions, political view points, financial planning, and others. By detecting the opinion expressed, we can identify the sentiments on the topics discussed and the influence exerted on the readers. In this paper, we introduce an automatic approach in deriving polarity pattern rules to detect sentiment polarity at the phrase level, and in addition consider the effects of the more complex relationships found between words in sentiment polarity classification. Recent sentiment analysis research has focused on the functional relations of words using typed dependency parsing, providing a refined analysis on the grammar and semantics of textual data. Heuristics are typically used to determine the typed dependency polarity patterns, which may not comprehensively identify all possible rules. We study the use of class sequential rules （CSRs） to automatically learn the typed dependency patterns, and benchmark the performance of CSR against a heuristic method. Preliminary results show CSR leads to further improvements in classification performance achieving over 80% F1 scores in the test eases. In addition, we observe more complex relationships between words that could influence phrase sentiment polarity, and further discuss on possible approaches to handle the effects of these complex relationships.

Modification Method of Longitudinal Bow Structure for Ice-Strengthened Merchant Ship

:Merchant ships,which are quite different from icebreakers,usually require the light ice-strengthened bow under the floe-ice condition.According to ice-class B,requirements of China Classification Society(CCS),intermediate frames and thick hull plates are necessary for the ice belt area to resist floe-ice impact.However,due to the limited space,it is not practical to set so many intermediate longitudinals from manufacture point of view.In this paper,a modification method is proposed to solve the problem by maintaining the frame spacing and increasing the plate thickness.The aim is to make sure that the bow owns the equivalent ice-bearing capacity with the original frame spacing.At first,a bulk carrier with ice-class B is used for case study.According to the requirements of the ice class rule,a designed ice thickness is used to calculate the ice load acting on the bow area due to the impact of ice floe.Two structural models are presented to perform the strength analysis under ice load,including the out-shell plate model and the longitudinal model.The results show that increasing the plate thickness is helpful to remove the negative effect induced by enlarging the spacing of the longitudinal.A reasonable curve is presented to modify the bow for the ice-strengthened merchant ship,which shows the relationship between the increase of plate thickness and the spacing of longitudinal.Moreover,a model test of floe-ice–ship interaction is conducted to measure the dynamic ice load,based on which nonlinear dynamic FE analysis is used to verify the presented plate-thickness–longitudinal spacing curve.The results show that the proposed method can be used to improve the ice-strengthened bow structure effectively,which provides theoretical foundation to modify the requirement of CCS’s ice class rule.