JPH09231227A - Information retrieval device and method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a relative document via a key word by retrieving the document which includes a synonym of the key word and a word having the same meaning attribute as the key word that are approximate to each other. SOLUTION: A CPU 1 temporarily stores the word serving as an input key word in a RAM 3 and tries to retrieve a word that is completely coincident with the key word out of a document data base. If the coincident word cannot be retrieved, the CPU 1 retrieves a synonym of the key word. That is, the input word stored in the RAM 3 is decomposed into the words of minimum units and the words which are not used for the retrieval are eliminated, so that a synonym retrieval key word is obtained. Thus the CPU 1 refers to a word associative dictionary based on the obtained key word to acquire a synonym and a meaning attribute code. Then the CPU 1 retrieves a document that includes the synonym and also has a word having the same meaning attribute acquired from a meaning attribute system dictionary as the key word in a range of the prescribed length including the said synonym out of the document data base of a hard disk storage 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information retrieval apparatus and an information retrieval method for semantically retrieving data from a stored document database.

[0002]

2. Description of the Related Art Conventionally, there has been known an information search apparatus which stores document data in an information processing apparatus such as a personal computer and detects a word or phrase described in the document data by a keyword search. In order to improve the accuracy of search, an information search device that searches for a word or phrase in a document that includes a part of a character string given by the user has also been put into practical use. Further, there is also proposed an information search device, such as Japanese Patent Laid-Open No. 6-266770, which converts a character string given by a user into a synonym and searches for a synonym to detect a synonym in a document.

[0003]

However, in the search using the above-described information search device, the accuracy of the search is poor only by the exact match, the partial match, and the synonyms of the character string given by the user, and the search accuracy is poor. , There is a growing demand for improved search accuracy. For example, when a synonym search is performed to search for the corresponding document, sentence, paragraph, etc., and a search result of 500 points is obtained, the user must confirm the content of the 500 points on the display screen. The operation for this is very complicated for the user.

Therefore, in view of the above points, an object of the present invention is to provide an information search apparatus and an information search method therefor, which improve the search accuracy by using a search method that has never been available.

[0005]

In order to achieve such an object, the invention of claim 1 is equipped with a document database having a plurality of documents, and a document having a character string related to a given keyword is provided. In an information search device for searching, a word association dictionary in which a word and its synonyms are described,
A semantic attribute system dictionary describing words and their semantic attributes; a means for obtaining synonyms for the keywords from the word association dictionary; a means for obtaining semantic attributes for the keywords from the semantic attribute system dictionary; And a means for searching the document database for a document having the acquired synonym and having a word having the same acquired semantic attribute within a predetermined length range including the synonym. Is characterized by.

According to a second aspect of the present invention, in the information retrieval apparatus according to the first aspect, the keyword is composed of a plurality of words, and further comprises means for removing a predetermined word from the keyword as an unnecessary word. It is characterized by

According to a third aspect of the present invention, in the information retrieval apparatus according to the first aspect, the range of the predetermined length is composed of a character string of a predetermined number or more, and is a word string that semantically constitutes one word. Yes, the searching means acquires the semantic attribute of the word located at the end of the word string from the semantic attribute system dictionary, compares it with the semantic attribute of the keyword, and determines whether there is a match. And

According to a fourth aspect of the present invention, in the information retrieving apparatus according to the first aspect, the retrieving means retrieves a synonym-related document containing only the synonym in the document database in the process of retrieval. It is characterized by

The invention of claim 5 further comprises means for displaying information for notifying the document obtained by the search of claim 1 and the synonym-related document obtained by the search of claim 4. It is characterized by having

According to a sixth aspect of the present invention, in the information retrieval apparatus according to the fifth aspect, the displaying means is obtained by the document obtained by the retrieval according to the first aspect and the retrieval according to the fourth aspect. It is characterized in that information for notifying synonym-related documents is displayed separately.

According to a seventh aspect of the present invention, in the information retrieval apparatus according to the fifth aspect, the document obtained by the retrieval according to the first aspect and the synonym-related document obtained by the retrieval according to the fourth aspect are obtained. The information for notifying is characterized by being a part of the document and the synonym-related document.

According to an eighth aspect of the present invention, there is provided an information search method for an information search apparatus which is equipped with a document database having a plurality of documents and searches for a document having a character string associated with a given keyword. And a semantic attribute system dictionary in which words and their semantic attributes are described are installed in advance in the information search device, and the information search device is configured to generate synonyms for the keywords in the word association dictionary. Obtained from the semantic attribute system dictionary, the obtained semantic attribute has the same synonym, and the obtained semantic attribute is the same within a predetermined length range including the synonym. It is characterized in that a document in which the word is present is searched in the document database.

According to a ninth aspect of the invention, in the information retrieving method of the information retrieving apparatus according to the eighth aspect, a document including a word matching the keyword is searched in the document database, and when there is no corresponding document. The present invention is characterized in that the search is performed according to claim 8.

According to the invention of claim 10, in the information search method of the information search device according to claim 8, a sentence including the synonym of a document obtained as a search result is displayed on a display screen, and the synonym and The feature is that words having the same semantic attribute are displayed in a distinguishable manner.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an example of a system configuration of an information search device to which the present invention is applied. An information processing device such as a personal computer or a workstation can be used as the information retrieval device. In FIG. 1, the information retrieval apparatus has a CPU 1, a ROM 2, a RAM 3, an input interface 4, a hard disk storage device 7, a floppy disk drive and an output interface 9.
The CPU 1 performs system processing by a system program stored in the ROM 2 or the hard disk storage device 7, for example, reading / writing of information from / in a memory or storage device, character code-image conversion (displaying information on a display device 11 described later). Called), display control, control of the printer 10, and reception of input information from the keyboard 5 and the mouse 6. The ROM 2 stores a system program for executing the above system processing and related information.

The RAM 3 temporarily stores information used by the CPU 1 for information processing and information processing results. As information related to the present invention, the document information acquired from the document database of the hard disk storage device 7 is temporarily stored. The input interface 4 CP receives input information from a keyboard 5 and a coordinate input device (hereinafter, referred to as a mouse) 6 such as a mouse.
Transfer to U1.

The keyboard 5 is mainly used for character input. The mouse 6 is used to specify a position on the display screen.
In addition to the system program, the hard disk storage device 7 stores an information search program according to the present invention, a document database to be searched, a word association dictionary used for information search, and a semantic attribute system dictionary. The word association dictionary and the semantic attribute system dictionary are related to the present invention, and will be described in detail later. The document database of this embodiment is composed of a plurality of documents, and this document has at least a document name (file name) and document data in the form of character code.

The floppy disk drive 8 receives a floppy disk and reads / writes information from / to this floppy disk. Floppy disks are used to register documents created elsewhere in the document database. The output interface 9 transfers information to be displayed or printed and control information to the printer 10 and the display device 11.

In this system configuration, in this embodiment, a synonym search is performed on the document database, and when a plurality of relevant search results are obtained, the sentence containing the synonym is examined. When a sentence has a word having the same semantic attribute as that of a keyword, the sentence is treated as a search result with a high weight.

A detailed description for this will be given below. FIG. 2 shows a part of the contents of the word association dictionary used for the above information retrieval.
FIG. 3 shows a part of the contents of the semantic attribute system dictionary.
The word association dictionary is composed of a plurality of records, and one record is a character string of one character kanji, word, phrase, etc. (hereinafter collectively referred to as word) 51, an identification code assigned to the word, a synonym (including similar words). ) 53 and an identification code (referred to as a semantic attribute code) indicating a semantic attribute associated with the word. If necessary, other information, for example, grammatical information indicating a noun, an adjective, etc., or a word reading (notation) can be added.

The meaning attribute system dictionary is also composed of a plurality of records, and one record has a word, an identification code (meaning attribute code) indicating the meaning attribute of the word, and a character string of the word indicating the meaning attribute. The words (including one-character kanji) described in the semantic attribute system dictionary are included in one or more word strings, and words frequently used as the last word are prepared in advance. The Chinese character “person” shown in FIG. 3 is a word used at the end of a word string of a companion, an administrator, or the like. FIG. 3 shows that the meaning attributes of person and organization are given to this word, and the identification code of 1001 is given to this meaning attribute.

Information retrieval processing using such a word association dictionary and a semantic attribute system dictionary will be described with reference to FIGS. 4 and 5. FIG. 4 functionally shows the processing contents of the information retrieval processing program stored in the hard disk storage device 7. FIG. 5 shows detailed processing in the processing of FIG. When the execution of the search is instructed from the keyboard 5, the information search program shown in FIG. 4 is activated and the CPU 1 starts the information search process. As an example of the information search, an example will be described in which a character string of the word "Natsuko Koshien" is given and the corresponding sentence of the document in which the word related to this word is described is searched.

When the user inputs "summer koshien" as a keyword from the keyboard 5, the CPU 1 accepts the input word, that is, "summer koshien", and the RAM 3
(Step S10).

Next, the CPU 1 searches the document database for a word that exactly matches this keyword. Since this processing is similar to the conventional search processing, detailed description will not be required. When the corresponding word is found, the sentence or document containing the word, the document name, or the like is displayed (steps S20 → S30 → S35).

On the other hand, if no perfectly matched word is detected, the CPU 1 shifts to a synonym search. The input word "Natsuno Koshien" in the RAM 3 is decomposed into the minimum unit words "Natsuno" and "Koshien", and words not used for the search are removed (step S40). This criterion can be, for example, a word not described in the word association dictionary or a predetermined word having no synonym described in the word association dictionary as an unnecessary word. Also, words that you normally don't use, such as? It is good to remove characters such as, @.

In the case of this example, "Natsuno" is excluded and "Koshien" is obtained as a keyword for synonym search. Note that the method for word decomposition is well known in the name of syntax analysis, and thus detailed description will not be required. The simplest method is to divide a character string into words that are listed in a word association dictionary. The CPU 1 refers to the word association dictionary based on the obtained keyword "Koshien" to acquire the synonym "high school baseball" and the meaning attribute code "2004" (step S50, see FIG. 2).

Next, the CPU 1 searches the document database of the hard disk storage device 7 to search for the document in which the acquired synonyms are described (step S60). When the corresponding document is found (YES determination in step S70), the degree of association between the keyword (Koshien) given by the user and the synonym (high school baseball) is weighted, that is, the degree of association. Is calculated (step S
80). The detailed procedure for this is shown in FIG.

In FIG. 5, the CPU 1 extracts sentences including synonyms from the documents obtained as a result of the search.
A simple method is to detect a character code such as "." Before and after a synonym, a space character, etc., which represents a break in a sentence, and take out a character string sandwiched by this character code as a sentence (step S10).
0). The extracted sentence is decomposed into words, and more specifically, the sentence is decomposed into words (including phrases etc.) composed of a character string of four characters or more, excluding predetermined unnecessary words.
110). Then, the word (which has the minimum unit length among the words including the synonyms and is located at the end is extracted. For example, the extracted sentence is "This year's National High School Baseball Players Competition ... ", The character string of" National High School Baseball Tournament "is extracted as a word of four characters or more (a word string composed of a predetermined number or more of character strings and semantically forming one word). "Convention" is taken out as the minimum unit length word of.

Regarding this word "meeting", the CPU 1
With reference to the semantic attribute system dictionary of “,” “2004” is acquired as the semantic attribute code. When such processing is performed on all search results (documents including synonyms), a semantic attribute code is obtained for each document (steps S120 → S).
130). As described above, the semantic attribute code of the user's keyword “Koshien” has already been checked and the RAM
3, the CPU 11 compares the meaning attribute code (2004) of the keyword of the user with a plurality of meaning attribute codes derived from all documents of the search result (step S140). Documents in which a match is found are treated as documents with high relevance, and documents without a match are treated as documents with low relevance. These documents are stored in the corresponding areas on the RAM 3 (steps S150, S15).
5).

Returning to FIG. 4, the CPU 1 locates the relevant part in the document of the search result in the RAM 3 according to the degree of the degree of association (weight).
It is taken out from the display and displayed (step S90). An example of the display is shown in FIG. In this display example, the sentence in which the semantic attribute code matches is displayed as the final search result, and as a reference, that is, a sentence that includes a synonym but the semantic attribute code does not match is displayed as a reference and the related Degree of degree 2
It is an example divided into two.

As described above, in this embodiment,
In addition to the synonym search, a sentence in which a keyword and a semantic attribute match near a synonym (similar word) is detected, so a sentence close to the sentence the user is trying to find can be obtained. .

In addition to this embodiment, the following example can be implemented.

1) In this embodiment, the search target is a sentence described in the document, but a paragraph, the entire document, or the like may be the search target. Also, the type of sentence, paragraph, document, etc. may be designated from the keyboard. Further, instead of the content of the sentence, the title name or file name registered in the document database may be used as the search result, or these information and the relevant sentence may be displayed together. In other words, the document described in claim 1 includes the document itself, a part of the document, the document title, the file name, and the like.

2) In the present embodiment, the longest word including a synonym in a document (including a compound word) in order to detect a word in the document near a synonym having the same semantic attribute of a keyword.
Is taken out and the semantic attribute at the end is examined. This is because the inventor noticed that when the last word of the above longest word is Japanese, it represents the semantic attribute best, but if you want to improve search accuracy even at the expense of search time, The following detection method should be used. After extracting the sentence including the synonym, the word is extracted from the synonym as a starting point toward the beginning of the sentence and each direction toward the end of the sentence. The semantic attribute code of the retrieved word is retrieved from the semantic attribute system dictionary and compared with the semantic attribute code of the keyword. When a match is obtained, the sentence is treated as a sentence with high relevance. In addition, if you want to change the degree of search accuracy, you do not have to limit the search range of words that have the same semantic attributes as keywords to sentences that include synonyms, but you can selectively expand them to paragraphs, pages, or entire documents. Good. This selection is made for sentences, paragraphs. . . As described above, the survey range may be automatically expanded until a word having the same meaning attribute code is found, or the user may manually specify the survey range from the keyboard.

3) In this embodiment, the degree of association between the keyword and the sentence to be searched is divided into two levels, but it can be set in two or more levels. In this case, the number of sentences having a predetermined length including the synonyms, for example, words having the same meaning attribute included in one page is counted. The search accuracy can be divided into multiple levels according to this numerical value.

4) As the display form of the search result, in addition to the sentence including the synonym, the longest word including the synonym is displayed in a rectangle as shown in FIG. It is possible to inform the user of words related to the keyword, such as displaying in color. Further, as the notification form, it is conceivable that a color, a figure such as a rectangle, a typeface change, an underline addition, a character size change, or the like.

5) The information retrieval apparatus may be used alone or may be connected to a communication line to accept a keyword from another computer requesting retrieval and returning the retrieval result to the computer requesting retrieval. Can also be considered. In this case, the information retrieval device may be equipped with a communication means.

6) The storage location of the document database installed in the information retrieval device is not limited to the hard disk storage device, and any suitable known storage means such as a magneto-optical storage device may be used.

[0039]

As described above, according to the inventions of claims 1 and 8, both a synonym and a word having the same semantic attribute are provided for a keyword, and these two words are close to each other. Since the searched documents are searched, the related documents can be obtained by the keyword as compared with the case where the synonyms alone or the semantic attributes alone are continuously searched.

According to the second aspect of the invention, the user can use a keyword composed of a plurality of desired words without preparing a single word.

According to the third aspect of the present invention, it is possible to extract the word that is most related to the synonym and represents the semantic attribute.

According to the fourth aspect of the present invention, a search result obtained only by the synonym search is also obtained, so that the omission of the search due to the narrowing down of the keyword is eliminated.

According to the fifth aspect of the present invention, the user can know the content and location of the document by displaying the title of the document, the document itself, and a part of the document.

According to the invention of claim 6, the user can know the location of the document according to the degree of association of the keywords.

According to the invention of claim 7, by displaying a part of the document as a search result, the degree of association with the keyword can be confirmed by the user.

According to the invention of claim 9, the search time and the search accuracy can be balanced by executing the synonym search related to the present invention after performing the keyword matching search.

According to the tenth aspect of the invention, the user can know the synonyms and the words of the semantic attribute used for the automatic search.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration of an information search device to which the present invention is applied.

FIG. 2 is an explanatory diagram showing a part of the contents of a word association dictionary.

FIG. 3 is an explanatory diagram showing a part of the contents of a semantic attribute system dictionary.

FIG. 4 is a flowchart showing a processing procedure related to information search.

FIG. 5 is a flowchart showing a processing procedure related to information search.

FIG. 6 is an explanatory diagram showing a display example of search results.

[Explanation of symbols]

 1 CPU 2 ROM 3 RAM 4 Input Interface 5 Keyboard 6 Mouse 7 Hard Disk Storage Device 8 Floppy Disk Drive 9 Output Interface 10 Printer 11 Display Device

Claims (10)

[Claims] 1. An information retrieval apparatus which is equipped with a document database having a plurality of documents and retrieves a document having a character string related to a given keyword, including a word association dictionary in which a word and its synonym are described, and a word. And a semantic attribute system dictionary describing the semantic attributes thereof, means for obtaining synonyms for the keywords from the word association dictionary, means for obtaining semantic attributes for the keywords from the meaning attribute system dictionary, And a means for searching the document database for a document that has a synonym and that has a word having the same acquired semantic attribute within a predetermined length range including the synonym. Characteristic information retrieval device. 2. The information search device according to claim 1, wherein the keyword is composed of a plurality of words, and further comprises means for removing a predetermined word from the keyword as an unnecessary word. Information retrieval device. 3. The information search device according to claim 1, wherein the range of the predetermined length is a word string that is composed of a predetermined number or more of character strings and semantically constitutes one word, and the search is performed. An information retrieval device characterized in that the means acquires the semantic attribute of the word located at the end of the word string from the semantic attribute system dictionary, compares it with the semantic attribute of the keyword, and determines whether or not there is a match. . 4. The information retrieving apparatus according to claim 1, wherein the retrieving means retrieves a synonym-related document containing only the synonym in the document database in the retrieval process. Information retrieval device. 5. The apparatus further comprises means for displaying information for notifying the document obtained by the search according to claim 1 and the synonym-related document obtained by the search according to claim 4. Information retrieval device. 6. The information search device according to claim 5, wherein the displaying means displays the document obtained by the search according to claim 1 and the synonym-related document obtained by the search according to claim 4. An information retrieval device characterized in that information for notification is displayed separately. 7. The information search device according to claim 5, wherein the information for notifying the document obtained by the search according to claim 1 and the synonym-related document obtained by the search according to claim 4 Is an information retrieval device characterized by being a part of the document and a synonym-related document. 8. An information search method for an information search apparatus, which is equipped with a document database having a plurality of documents and searches for documents having a character string related to a given keyword, in a word association in which a word and its synonym are described. A dictionary and a semantic attribute system dictionary that describes words and their semantic attributes are installed in advance in the information retrieval device, and the information retrieval device is
A synonym for the keyword is acquired from the word association dictionary, a semantic attribute for the keyword is acquired from the semantic attribute system dictionary, the synonym is acquired, and the synonym has a predetermined length. An information retrieval method for an information retrieval apparatus, characterized in that a document in which a word having the same semantic attribute is present within the range is searched in the document database. 9. The information search method of the information search device according to claim 8, wherein a document including a word that matches the keyword is searched in the document database, and when there is no corresponding document, the document search is performed. An information search method for an information search device, characterized in that the method shifts to the search. 10. The information search method for an information search device according to claim 8, wherein a sentence including the synonym of a document obtained as a search result is displayed on a display screen, and the synonym and the semantic attribute are the same. The information search method of the information search device, wherein the word is displayed in a distinguishable manner.