In this paper, we report the experimental results of Machine Translation models conducted by a NECTEC team for the translation tasks of WAT-2021. Basically, our models are based on neural methods for both directions of English-Myanmar and Myanmar-English language pairs. Most of the existing Neural Machine Translation (NMT) models mainly focus on the conversion of sequential data and do not directly use syntactic information. However, we conduct multi-source neural machine translation (NMT) models using the multilingual corpora such as string data corpus, tree data corpus, or POS-tagged data corpus. The multi-source translation is an approach to exploit multiple inputs (e.g. in two different formats) to increase translation accuracy. The RNN-based encoder-decoder model with attention mechanism and transformer architectures have been carried out for our experiment. The experimental results showed that the proposed models of RNN-based architecture outperform the baseline model for English-to-Myanmar translation task, and the multi-source and shared-multi-source transformer models yield better translation results than the baseline.

This paper aims to develop a framework for automatic CG tagging. We investigated two main algorithms, CRF and Statistical alignment model based on information theory (SAM). We found that SAM gives the best results both in word level and sentence level. We got the accuracy 89.25% in word level and 82.49% in sentence level. Combining both methods can be suited for both known and unknown word.

Combinatorial Category Grammar is (CCG) a lexicalized grammar formalism which is expressed by syntactic category, a logical form representation. There are difficulties in representing CCG without any visualization tools. This paper presents a design framework of OpenCCG workbench and visualization tool which enables linguists to develop CCG based lexicons more easily. Our research is aimed to resolve these gaps by developing a user-friendly tool. OpenCCG Workbench, an open source web-based environment, was developed to enable multiple users to visually create and update grammars for using with the OpenCCG library. It was designed to streamline and speed-up the lexicon building process, and to free the linguists from writing XML files which is both cumbersome and error-prone. The system consists of three sub-systems: grammar management system, grammar validator system, and concordance retrieval system. In this paper we will mainly discuss the most important parts, grammar management and validation systems, which are directly related to a CCG lexicon construction. We support users in three levels; Expert linguists who play a role as lexical entry designer, normal linguists who adds or edits lexicons, and guests who requires an acquisition to the lexicon into their applications.

Rule-Based Machine Translation (RBMT) [1] approach is a major approach in MT research. It needs linguistic knowledge to create appropriate rules of translation. However, we cannot completely add all linguistic rules to the system because adding new rules may cause a conflict with the old ones. So, we propose a memory based approach to improve the translation quality without modifying the existing linguistic rules. This paper analyses the translation problems and shows how this approach works.

This paper presents an online Thai-English MT system, called PARSITTE, which is an extension of PARSIT English-Thai one. We aim to assist foreigners and Thai in exchanging more easily their information. The system is a rule-based and Interlingua approach. To improve the system, we concentrate on pre-processing and rule analysis phases, which are considered necessary because of some specific problems of Thai language.