1. English-Korean Machine Translation System
Sung-Dong Kim
Dept. of Computer System Engineering,
Hansung University

2. Dept. of CSE, Hansung Univ.
Contents
History
Methodologies
System Structure
Capabilities of EKMT System
Dept. of CSE, Hansung Univ.

3. Dept. of CSE, Hansung Univ.
History (1)
KSHALT (Korean System for Human Assisted Language Translation)
Late 1980’s
Implemented using LISP
Run on IBM 3090 mainframe
Enkor
1991 ~ 1995
Implemented using C
Dept. of CSE, Hansung Univ.

4. Dept. of CSE, Hansung Univ.
History (2)
ETran
Several versions: 98, 99, 2000, 2003
Enhanced version of Enkor
Text translation, internet translation on browser
SmarTran
2004
Provide more user-friendly capabilities
Improve dictionary access time
Dept. of CSE, Hansung Univ.

5. Dept. of CSE, Hansung Univ.
Methodologies (1)
Rule-based method
Transfer method
Idiom-based analysis and translation
Statistical method
Dept. of CSE, Hansung Univ.

6. Dept. of CSE, Hansung Univ.
Methodologies (2)
Rule-based method
Context free grammar
Phrase, clause, sentence structures
Dept. of CSE, Hansung Univ.

7. Dept. of CSE, Hansung Univ.
Methodologies (3)
Transfer method
Using transfer rules
About 70 rules
Structural transfer for catching up with the differences between English and Korean
“little”: negative meaning in Korean
It ~ to-INF: real, pseudo subject, object relation …
Dept. of CSE, Hansung Univ.

8. Dept. of CSE, Hansung Univ.
Methodologies (4)
Idiom-based analysis and translation
Reduce analysis complexity
Enhance translation quality
bread and butter:
Not bread and butter but bread spread with butter
Takes one edge instead of three in chart
provide him with money
Provide A with B
Give him a money
Dept. of CSE, Hansung Univ.

9. Dept. of CSE, Hansung Univ.
Methodologies (5)
Statistical method: intra-sentence segmentation based on maximum entropy
Partial parsing: reduce parsing complexity  long sentence analysis
Maximum entropy probability model
Dept. of CSE, Hansung Univ.

10. Dept. of CSE, Hansung Univ.
Structure (1)
English sentences
Lexical Rules
Lexical Analysis
Lexical Dictionary
Syntactic Rules
Syntactic Analysis
EK Transfer
Dictionary
Transfer
EK Transfer
Rules
Korean Dictionary
Korean Generation
Korean
Generation
Rules
Korean sentences
Dept. of CSE, Hansung Univ.

11. Dept. of CSE, Hansung Univ.
Structure (2)
System modules
Lexical analysis
Syntactic analysis: Parser
Chart-based parsing
Idiom-based analysis
Idiom recognition before parsing
Partial parsing using intra-sentence segmentation
Transfer
Korean generation
Dept. of CSE, Hansung Univ.

12. Result of lexical analysis
Intra-sentence
segmentation
Segment 1
Segment 2 …
Segment n
EK Idiom
Dictionary
Idiom recognition &
translation
Grammar
Segment Analysis
Global structuring
Tree selection
Parser
Parsing tree
Dept. of CSE, Hansung Univ.

13. Dept. of CSE, Hansung Univ.
Structure (4)
Dictionaries
Lexical dictionaries
Word usage dictionary
About 70,000 entries
Information for POS probability calculation
Word information dictionary
About 83,000 entries
Information about POS, …
Dept. of CSE, Hansung Univ.

14. Dept. of CSE, Hansung Univ.
Structure (5)
EK transfer dictionary
Structure
Default meaning
Collocations
Idioms
General dictionary
For each POS: noun, adjective, adverb, verb, …
Domain dictionary
14 types: military, economy, politics, computer, medical, …
User dictionary
Facility for user to make his own dictionary
Dept. of CSE, Hansung Univ.

15. Dept. of CSE, Hansung Univ.
Structure (6)
Statistics of transfer dictionary
Number of entries
General dictionary: about 68,000
Noun: 40,546
Adjective: 16,255
Adverb: 2,671
Verb: 8,612
Domain dictionary: about 36,000
Number of idioms: 42,600
Number of collocations: 6,150
Dept. of CSE, Hansung Univ.

16. Dept. of CSE, Hansung Univ.
Structure (7)
Rules
Lexical rules
Syntactic rules
About 600 syntactic rules
Transfer rules
Korean generation rules
Dept. of CSE, Hansung Univ.

17. Capabilities of EKMT system
Text translation
Internet translation on the browser
MS-office document translation
Dept. of CSE, Hansung Univ.