tailieunhanh - Báo cáo khoa học: "Tractability and Structural Closures in Attribute Logic Type Signatures"

This paper considers three assumptions conventionally made about signatures in typed feature logic that are in potential disagreement with current practice among grammar developers and linguists working within feature-based frameworks such as HPSG: meet-semilatticehood, unique feature introduction, and the absence of subtype covering. | Tractability and Structural Closures in Attribute Logic Type Signatures Gerald Penn Department of Computer Science University of Toronto 10 King s College Rd. Toronto M5S 3G4 Canada gpenn@ Abstract This paper considers three assumptions conventionally made about signatures in typed feature logic that are in potential disagreement with current practice among grammar developers and linguists working within feature-based frameworks such as HPSG meet-semi-latticehood unique feature introduction and the absence of subtype covering. It also discusses the conditions under which each of these can be tractably restored in realistic grammar signatures where they do not already exist. 1 Introduction The logic of typed feature structures LTFS Carpenter 1992 and in particular its implementation in the Attribute Logic Engine ALE Carpenter and Penn 1996 have been widely used as a means of formalising and developing grammars of natural languages that support computationally efficient parsing and SLD resolution notably grammars within the framework of Head-driven Phrase Structure Grammar HPSG Pollard and Sag 1994 . These grammars are formulated using a vocabulary provided by a finite partially ordered set of types and a set of features that must be specified for each grammar and feature structures in these grammars must respect certain constraints that are also specified. These include appropriateness conditions which specify for each type all and only the features that take values in feature structures of that type and with which types of values value restrictions . There are also more general implicational constraints of the form T f where T is a type and is an expression from LTFS s description language. In LTFS and ALE these four components a partial order of types a set of features appropriateness declarations and type-antecedent constraints can be taken as the signature of a grammar relative to which descriptions can be interpreted. LTFS and ALE also make .

• Báo cáo khoa học
• Tractability
• Structural Closures
• Attribute Logic Type Signatures
• báo cáo khoa học
• mô hình ngôn ngữ
• xử lý ngôn ngữ tự nhiên
• Algorithm design
• Lecture Algorithm design
• Algorithm analysis
• Vertex covers
• Bipartite graphs
• Limits of tractability
• Computational tractability
• Asymptotic order of growth
• Polynomial running time
• Design and Analysis of Algorithms
• Analysis of Algorithms
• Design of Algorithms
• Data structures
• Linear programming
• Fixed Parameter Algorithms
• Vertex cover
• Fixed Parameter Tractability
• Bài giảng Xử lý ngôn ngữ tự nhiên
• Ngôn ngữ tự nhiên
• Kỹ thuật lập trình
• Xử lý nhập nhằng ngữ nghĩa
• Xử lý ngữ nghĩa
• Xử lý ngôn ngữ
• Natural Language Processing
• Ngôn ngữ lập trình
• Nhập nhằng cấu trúc
• Tri thức về ngôn ngữ
• Mô hình n gram
• Dịch máy
• Phương pháp dịch máy
• Hiểu ngôn ngữ
• Phân tích ngữ nghĩa
• Phân loại tin tự động
• Biểu diễn vị từ
• Thuộc tính về sự kiện
• Thuộc tính về sự kiện
• Mô hình ngôn ngữ Google Book N grams
• Mô hình ngôn ngữ KenLM
• Phương pháp làm mịn
• Tách từ tiếng Việt
• Gán nhãn từ loại
• Phân tích cú pháp
• Nghĩa từ vựng
• Phân giải nhập nhằng từ
• Phân loại văn bản
• Lexical chain
• Phản hồi thông tin
• Bài toán PTCP
• Cấu trúc ngữ pháp
• Phân tích cú pháp xác suất
• CKY kết hợp xác suất
• Văn phạm phi ngữ cảnh xác suất
• Hình thái học