JP2002099558A - Information retrieval system, information retrieval method, and recording medium - Google Patents

Abstract

(57) [Summary] [Problem] To realize an information search corresponding to a limitation such as a display amount of a search result. After searching for information based on a search character string, a character string included in the searched information is extracted within a range of a predetermined number of characters, and the extracted character string is displayed as a search result. In the extraction of the character string, at least one, preferably, a plurality of words relevant to the word extracted from the search character string among words included in the searched information is included.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an information retrieval technique.

[0002]

2. Description of the Related Art In information retrieval of documents, figures, images, and the like,
By performing a search based on information entered by the user with keywords attached to data such as documents and graphics to be searched in advance, and all or some words and character strings in the documents as search targets And a method of selecting information such as a corresponding document or graphic.

In this case, information input by a user at the time of a search includes a keyword, a word or a sentence, a classification code of information, and the like, and the search result is information such as a sentence or a figure to be searched or an instruction for the information. There are serial codes that can be used.

On the other hand, with the advancement of the search function of the information search device, it becomes possible to search for ambiguity of expressions and expressions similar in meaning to input keywords and words, and to search for katakana, synonyms, and the like. Even information containing synonyms can be included in search results. As a result, oversight of information desired by the user is less likely to occur.

However, since the search is not performed while understanding the contents of the information, the user is inevitably shown the search result, and is required to select desired information or to add / retrieve search conditions. Unless a search is performed again when the change / deletion is performed, that is, a so-called additional search is performed, what the user wants cannot be provided.

[0006] Therefore, it is necessary to make it easy to view the search results, to make effective use of the search results, and to easily perform information selection and additional search. For this reason, in the case of searching for figures and the like, functions such as displaying a reduced version of the figure to be searched, a thumbnail display, etc. have been proposed so that a lot of figures of the search result can be displayed on the screen, In the case of document search, for example, a function of partially displaying a part of a document summary or the like has been proposed.

[0007]

However, in any case, a display screen or the like for displaying a search result includes:
There is a limited display area, especially when displaying search results on portable small terminals etc., which are being developed recently.
It is remarkable. If the display area is small like this,
Information such as long sentences takes a lot of trouble to see the whole, and conversely, when reducing the amount of information, what kind of information is provided as a search result is an important issue.

Accordingly, it is an object of the present invention to provide an information search system, an information search method, and a recording medium that can realize an information search corresponding to a limitation on a display amount of a search result or the like.

[0009]

According to the present invention, there is provided a means for obtaining a document indicating the contents of information to be searched, and, among the information, information relating to a search character string given as a search condition. Searching means for searching, word extracting means for extracting words included in the search character string, and characters for extracting a character string included in the document relating to the searched information within a predetermined number of characters String extracting means, wherein the character string extracting means includes at least one word relevant to a word extracted from the search character string among words included in the document. An information retrieval system characterized by extracting a character string is provided.

According to the present invention, a step of obtaining a document indicating the contents of the information to be searched, and a step of searching the information related to a search character string given as a search condition from the information are provided. Extracting a word included in the search character string, and extracting a character string included in the document related to the searched information within a preset number of characters. In the character string extracting step, extracting the character string so as to include at least one word that is relevant to the word extracted from the search character string among words included in the document. A featured information retrieval method is provided.

According to the present invention, a computer is
A means for obtaining a document indicating the content of the information to be searched;
Search means for searching for information related to a search character string given as a search condition, word extraction means for extracting words included in the search character string, included in the document related to the searched information A character string to be extracted, in a range of a predetermined number of characters, a character string extracting means for extracting, a recording medium recording a program to function as, the character string extracting means, of the words included in the document, A recording medium is provided, wherein the character string is extracted so as to include at least one word relevant to the word extracted from the search character string.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an information retrieval apparatus A according to one embodiment of the present invention.

The information retrieval apparatus A can be realized on a general-purpose computer, and mainly has the following configuration.

The CPU 1 is a microprocessor,
It performs calculations for character processing, makes logical decisions, and controls other components via the bus 8. The ROM 2 is a read-only fixed memory. The ROM 2 stores a program for a search process to be described later, which is executed by the CPU 1. The RAM 3 is a writable random access memory, and is used as a temporary storage area for various data generated by the processing of the CPU 1, but can also be used to store a program for the search processing.

The disk 5 is an external memory for storing various data and the like. Various data and the like are stored on the disk 5 as needed, and the stored data is called up on the RAM 3 when necessary according to instructions from the keyboard 6 and instructions of various programs and processed by the CPU 1.

The disk 5 has a database 5a for storing the entity of the information to be searched and a document indicating the contents of the information, a database 5b for storing index information used for searching information, and the like. Has been built. When the type of information is image data, a document indicating the content of the information (hereinafter, referred to as an information document) is a pre-created keyword indicating the content of the image, an abstract,
If the type of information is character data such as text data, the information itself (in this case, the data is duplicated, so it is sufficient to store one of them) or the content of the information. The keyword may be a pre-created keyword, a summary sentence, an explanation sentence, or the like. The character string included in this information document is used as a search result.

The keyboard 6 is provided with various function keys such as an alphabet key, a hiragana key, a katakana key, a character symbol input key such as a punctuation mark, and a cursor movement key for instructing a cursor movement. Used for input etc. The display 7 is, for example, a CRT using a cathode ray tube or the like, and displays search conditions, search results, and the like input from the keyboard 6.

The communication interface 4 is for performing information communication with another computer 10 via the network 9. In this embodiment, the information search device A alone can input search conditions, execute search processing, and display search results. However, since the communication interface 4 is provided, the computer 10 It is also possible to receive input search conditions, execute search processing, and return search results to the computer 10.

The computer 10 is a general-purpose computer or a portable terminal having a configuration similar to that of the information search device A. A device such as a keyboard 6 for inputting search conditions and information communication with the information search device A are performed. A communication device such as a communication interface 4 for performing
It is conceivable to provide a display device such as a display 7 for displaying search results. In the present embodiment, the description will be made assuming that the computer 10 is a portable terminal. <Overall Process Flow> Next, the overall flow of the information search process executed in the information search device A will be described. FIG. 2 is a flowchart illustrating a flow of an information search process performed in the information search device A. In step S1, a character string serving as a search condition (hereinafter, a character string)
It is called a search string. ) Is received and analyzed in order to obtain information necessary for subsequent processing from the received search character string. In step S2, information search is performed according to the analysis result of the received character string.

In step S3, a series of character strings (hereinafter, also referred to as output character strings) included in the information document to be output as search results are extracted. Where, in general,
When a search result is output and displayed on a display or the like, it is difficult to display all of the contents of each searched information because there is a certain limit on a display amount. Displaying is not convenient for searching. Therefore, in the present embodiment, as described later, in order to make it easy for the user to understand, of the character strings included in the information document,
A character string having a certain relationship with the search character string is extracted as a search result. In step S4, the search result is output, and the process ends. Hereinafter, each process will be described in detail. <Reception and Analysis of Search Character String> The information search device A employs a character string as a search condition. Therefore, the user inputs a search character string from the keyboard 6 or the computer 10, for example.

FIG. 3 is an example of a display screen of a display (not shown) of the computer 10, which is an example of a screen for inputting a search character string. Since the computer 10 is assumed to be a portable terminal, its display screen is also small.

The input field 31 is a field for inputting a search character string, and the user inputs a character string related to the searched information here. In FIG. 3, a character string "Kyoto Garden" is input as a search character string. Search key 32
Is a key for instructing the information search device A to search for information. When this key is pressed, the search character string entered in the input box 31 is transmitted to the information search device A, and the information received The search device A starts information search.

Here, the information search device A analyzes the search character string given first for subsequent processing.
In the present embodiment, the following natural language analysis is executed.

In the information retrieval apparatus A, first, a given search character string is divided into words, and information indicating the nature of each word, for example, grammatical information such as part of speech, inflected forms, affixes, etc. Extract information such as the type of word. This is a process called so-called morphological analysis.

FIG. 4 shows the character string “Kyoto Garden”
It is a figure showing the analysis result which performed such morphological analysis, and the information which shows the property of the word is listed for every word contained in the character string. The word numbers in FIG. 4 are unique identification numbers only in this analysis information.

The information retrieval apparatus A extracts information on the relationship between words in the retrieval character string based on the result of the morphological analysis. This is a process called so-called syntax analysis.

FIG. 5 shows a character string “Walking through the gardens of Kyoto”.
FIG. 14 is a diagram showing an analysis result obtained by executing morphological analysis and syntax analysis on. By performing morphological analysis,
The words "Kyoto", "Garden", "Walk" and "Suru" are obtained, and by performing parsing on these words,
As shown in FIG. 5, a syntactic relationship between the words is obtained.
In the example of FIG. 5, the relationship between two words is shown, and the relationship number in FIG. 5 is a unique identification number only in this analysis information.

Various specific techniques for such natural language analysis processing have already been proposed, and detailed descriptions thereof will be omitted. However, in the present embodiment, regardless of the type of technique, the above-described method is used. Either one having a function of morphological analysis or one having a function of parsing can be adopted.

In this embodiment, a program for such a natural language analysis process is stored in the ROM 2.
It is assumed that the CPU 1 executes the program,
The present invention is not limited to this, and the information search device A includes independent hardware for executing a similar natural language analysis process,
Alternatively, it may be configured to be communicably connected thereto. Further, in order to execute such a natural language analysis process, information such as a dictionary is generally required, and these information are stored in a storage device such as the RAM 3 or the disk 5 in a timely manner. Will be secured and used. <Search of Information> Next, a description will be given of a search procedure of information related to a given search character string. In the information search device A of the present embodiment, a result obtained by executing a natural language analysis process on a search character string and a result obtained by executing a natural language analysis process on an information document attached to each piece of information. ,
Search for information based on. Needless to say, other methods may be used for information retrieval.

Here, in the information retrieval apparatus A, index information obtained by subjecting each information document to natural language analysis processing in advance is stored in the database 5b. This index information can be used for searching for information to be described below or extracting a character string to be described later (step S3), and may be created on the information inspection device A, or may be used for other devices. May be stored in the database 5b. 6 and 7 show examples of the index information.

FIG. 6 is a diagram showing each word, its part of speech, and index information indicating its appearance position in each information document, obtained by performing a morphological analysis on each information document in advance. An identification number, which is a word ID, is assigned to each word. With this index information, the word or word I
If D is known, it is possible to search for each word included in the search character string at which position in which information document. This implements an information retrieval function. For example, in the example of FIG. 6, the word "Kyoto" is
It can be seen that it exists at the fourth line of the third line of the information document 3 and the first line of the document 7.

In the present embodiment, index information obtained by further performing a syntax analysis on each information document is also stored in the database 5b, and the syntax analysis result of each word in the information document can be easily retrieved. Like that. FIG. 7 shows that after performing a morphological analysis on each information document in advance,
FIG. 9 is a diagram illustrating index information obtained by performing a syntax analysis and indicating a syntactic relationship between words included in each information document. According to the index information of FIG. 7, it is understood that the syntactic relationship between the words specified by the appearance position in each information document is shown (relation column).

In the present embodiment, such index information is created in advance and stored in the database 5b. However, a natural language analysis process is performed on the information document every time the information search process is performed. It is needless to say that the index information may be stored in another device or the like via the network 9. In addition, the database 5a stores the entity of the information to be searched and the document indicating the content of the information, but instead stores the document in one or more other devices via a network. Even if you do.

Next, a procedure of an information search using the index information will be described. FIG. 8 is a flowchart showing the information search process.

In step S11, based on the natural language analysis result of the given search character string, information (information document) related to the search character string is picked up. Specifically, by using the index information shown in FIG. 6, at least one of the words included in the search character string obtained by performing a morphological analysis on the given search character string is obtained. Pick up information documents that contain.

In this case, the words include, for example, fluctuations in expressions such as “computer” and “computer”,
Because there are words that have similar meanings but different expressions, etc., information about these words is stored in a dictionary in advance, and the words obtained by morphological analysis on the search character string using this are used. May be expanded, and an information document having these words may be searched from the index information in FIG.

For example, if the word "computer" is included in the search character string, an information document having words such as "computer", "computer", and "computer" is searched. Also, since a search string is usually considered to consist of multiple words, repeating the same for those words will collect information documents containing words and expressions likely to be related to the search string. Becomes possible.

Next, in step S12, in order to identify the information document that most closely matches the content of the given search character string, the similarity between the given search character string and the picked-up information document (the approximation of the content is approximated). Degree).

The degree of similarity is determined, for example, as to how many words each information document has corresponding to each word included in the search character string, or whether each word included in the search character string corresponds to the word. It can be calculated based on how close it is in the information document, or how much similarity is between each word included in the search string and each word of the corresponding information document. it can.

Further, based on the index information shown in FIG. 7, whether or not the syntactic relationship between words included in the search character string is the same as the relationship between words in the corresponding information document, It can also be calculated based on the above. As a result, a value of the similarity is assigned to each of the information documents picked up.

Next, in step S13, the information documents picked up are rearranged in descending order of similarity. This is so that information can be provided to the user in ascending order of similarity.
In addition, each information document should be easily identified by the user.
An ID number is assigned.

Next, in step S14, when displaying the search result, the range of the information document to be displayed on one display screen, that is, each page, is determined. Information with high similarity
It will be determined to be displayed on the first page. <Extraction of character string output as search result>
A procedure for extracting an output character string from each searched information document will be described. As described above, when a search result is output and displayed on a display or the like, since the display amount has a certain limit, it is difficult to output all the contents of the information document as the search result. As a result of the search, the number of characters set in advance (hereinafter, also referred to as a limited number of characters) is limited.

Therefore, in the present embodiment, a series of character strings (output character strings) in the information document are extracted and output as a search result so as to fall within the range of the number of characters, and particularly suitable for the user as the search result. To provide information, a character string that is highly relevant to the search character string is extracted.

FIG. 9 is a flowchart showing an outline of the character extracting process.

In step S21, one word is selected from the words included in the searched information document. The word selected here (hereinafter, also referred to as an essential word) is a word that is always included in the output character string, and the character string is extracted within the range of the limited number of characters based on this word.

The essential words are words that are related to the words included in the search character string, and include, for example, the same words as the words included in the search character string and the same or the same words as the words included in the search character string. Priorities are determined based on the parts of speech and syntactic relationships between those words,
The word having the highest priority or the word important in the syntax structure can be cited.

In selecting such an essential word, the index information stored in the database 5b can be used, or the above-described natural language analysis processing is performed on the information document every time a word is selected. And use the analysis results.

It is possible that the number of characters of the essential word exceeds the limit number of characters. In this case, another word can be selected or the essential word can be truncated to form an output character string.

Next, in this embodiment, the output character string includes a series of character strings including the essential word selected here and within the range of the limited number of characters, for example, centering on the essential word and before and after it. Although a character string in the range of the limited number of characters can be adopted, the following procedure can be further performed to extract a more appropriate output character string.

That is, in step S22, of the words included in the searched information document, another word to be included in the output character string is selected. This word is different from the required word selected in step S21, and a plurality of words can be selected.

By extracting the output character string so as to include other words as described above, more useful information as a search result can be obtained than by simply extracting the output character string based on the required words and the limited number of characters. Can be constructed.

In selecting another word, it is desirable to select a word having some relevance to the essential word.
Although various methods are conceivable, for example, a word having a certain syntactic relationship with an essential word can be selected. Specifically, words that negate essential words (such as “no”), words that modify essential words, and the like can be given.

When selecting another word, for example, a word corresponding to a word included in the search character string, such as the same word as a word included in the search character string, can be selected. When there are a plurality of words corresponding to the words included in the search character string, priority may be assigned and the words may be selected in order. The priority order can be determined based on, for example, the distance from the position of the essential word in the information document, the part of speech, the syntactic relationship between the words, and the like.

It is needless to say that some methods can be combined in selecting other words. Also, in selecting the word in this case,
Needless to say, the index information stored in the database 5b may be used, or the above-described natural language analysis processing may be performed on the information document every time a word is selected, and the analysis result may be used. Absent.

Next, in step S23, it is determined whether or not the number of characters of a series of character strings including the essential word and the word selected in step S22 is within the range of the limited number of characters. If the number of characters is within the range, the process proceeds to step S24. If the number of characters is not within the range, the process returns to step S22.
You will have to select another word again.

Next, in step S24, a series of character strings including the essential word and the word selected in step S22 are cut out from the information document as output character strings. In this case, it is preferable to cut out the cut-out character string within the range of the limited number of characters so that the beginning and the end of the cut-out character string become syntactical breaks as much as possible. As a result, the maximum number of characters can be utilized to the maximum, and search results that are easy for the user to read can be provided.

Next, a specific example of such a character string extraction process will be described. FIG. 10 is a flowchart illustrating a specific example of the character string extraction process.

In this case, the search character string is “Kyoto Garden” and the content of the searched information document is “A new service of virtual reality by XX Company. It is assumed that the process is started. "And that the limit character number is 20 characters.

In step S31, essential words are selected. Here, the search character string “Kyoto Garden” includes the words “Kyoto”, “No”, and “Garden”, and the corresponding words in the information document are “Kyoto”. , “No”, and “garden” are all included. Looking at the parts of speech, of these, “no” is a case particle, so its importance is low. Also, between "Kyoto" and "Garden", "Garden" is more important because the former qualifies the latter. Therefore, "garden" is selected as an essential word.

In step S32, it is determined whether or not the required word exceeds the limit character number. If the essential word is a very long word, the number of characters may exceed the limit at this point, so this branch is provided. If the required number of characters exceeds the limited number of characters, the process proceeds to step S41, where characters are truncated so as to be within the limited number of characters, this is set as an output character string, and the process ends.

In this example, the essential character is "garden" and does not exceed the limit of 20 characters. Therefore, the process proceeds to step S33.

In step S33, of the words included in the information document, another word having a syntactical relationship with the essential word is selected. Here, it is assumed that a word having a syntactical relationship that negates an essential word, such as negation “no”, is selected. In step S34, it is determined whether or not the character string including the essential word and the selected other word exceeds the limited number of characters. The number of characters in a string is determined by the number of characters in a required word,
It can be calculated by adding the number of characters of the selected other word and the number of characters of the character existing between the essential word and the selected other word.

If the number of characters exceeds the limit, the selected other word is canceled and the process proceeds to step S36. If not, the process proceeds to step S35 and the selected word is handled as a word to be included in the output character string.

In the case of this example, there is no word in the information document that denies the essential word "garden". Therefore, the process goes through steps S34 and S35 and proceeds to step S36.

In step S36, of the words included in the information document, another word corresponding to the word in the search character string is selected. In the case of this example, the words "Kyoto" and "no" are given, but "Kyoto" is more important in terms of part of speech. Therefore, "Kyoto" is selected. Step S3
At 7, it is determined whether or not a series of character strings including the essential word “garden” and another word “Kyoto” exceeds the limit number of characters. If the number of characters exceeds the limit, the selected other word, that is, "Kyoto" is canceled and the process proceeds to step S39. If not, the process proceeds to step S38 and the selected "Kyoto" is included in the output character string as a word. handle.

In this example, since a series of character strings in the information document including the essential word “garden” and another word “Kyoto” is “Kyoto garden”, it is 5 characters and is within the limit number of characters. is there. Therefore, the process proceeds to step S38, and "Kyoto" is handled as a word to be included in the output character string.

In this example, only one other word is selected in steps S36 to S38.
By assigning priorities to a plurality of other words based on parts of speech, syntactical relationships, and the like, these steps may be looped to include a plurality of words in the output character string. In this case, in this example, the word “no” is the next candidate.

In step S39, as a word to be included in the output character string, a word is added up to a syntactic break within the limit of the number of characters. In the case of this example, it is determined that the character string "Kyoto Garden" in the information document is included in the output character string, but there are 15 characters before the character limit is reached. Therefore, a word for 15 characters is added.

Here, looking at the character string before “Kyoto Garden” in the information document, it is found that “..., The famous Kyoto garden”. By the way, there is a break. Therefore, the output character string includes the above, that is, “a famous Kyoto garden” which is a series of character strings. As a result, the current number of characters is eight, and the remaining twelve characters up to the limited number of characters.

On the other hand, "Famous Kyoto Garden" in the information document
If you extract 20 characters from the later character string, it will be "Walk through the famous Kyoto garden on the Internet",
Since the syntactical delimitation at the end is bad, it is appropriate to delimit by "walk".

As described above, “famous” and “walk the Internet” are added to the output character string.

In step S40, a final output character string is cut out from the information document to determine the output character string.
In this example, as described above, a series of character strings “walk around the famous Kyoto garden on the Internet” is determined as an output character string.

With the above, the character string extraction processing is completed.
When extracting a character string, it is possible to make information within the limited number of characters useful by not adding a specific word or the like. As a specific word or the like not to be added, it is effective to perform an expression that does not have much meaning, such as an adverb such as “very” or “very”. By doing so, a lot of information on the contents of the search result candidates is shown. For example, in this example, it is conceivable to exclude "famous" and add another word or the like. <Output of search result> Finally, the output character string extracted as the search result is displayed on the display 7 in the form of a list, or
It is sent to the computer 10 and displayed on its display for output. FIG. 11 is a diagram illustrating an example of a display screen on a display (not shown) of the computer 10.

The display of the search result indicates the ID of the searched information.
A list format in which a number, an information title, and an output character string are described is adopted. In the example of FIG.
Information is displayed. Items related to the information in the range determined in step S14 described above are displayed on one display screen, and are displayed in order from the information determined to have a high degree of similarity. When the “next” button in FIG. 11 is pressed, the display screen shifts to the next page, and the searched information is sequentially displayed.

The user looks at the search result, selects the information he or she wants from the candidates, and sees the details of the information or
Alternatively, it is determined whether the search conditions are changed and the search is desired again. In the former case, when any of the search result candidates is selected, the entity of the information or the entire text of the information document of the information can be displayed.

As described above, according to the present embodiment, a series of character strings included in the information (information document) to be searched is extracted according to the limitation of the number of characters, and is provided to the user as a search result. Therefore, the convenience of information retrieval is improved.

In the extraction of a series of character strings, a word corresponding to a word included in the search character string as a search condition is included as an indispensable word. It also serves as an indication of the position in the retrieved information or how it appears, and the convenience of information retrieval is improved. In this case, by including a word related to the essential word, it can be a guide to know more accurate information positioning and the like, and an information search that can be easily used by the user can be provided.

Although the preferred embodiment of the present invention has been described above, an object of the present invention is to provide a storage medium (or a recording medium) on which a program code of software for realizing the functions of the above-described embodiment is stored in a system. Alternatively, it is needless to say that this can be achieved by supplying the program code to the device and causing the computer (or CPU or MPU) of the system or device to read and execute the program code stored in the storage medium. In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention. By executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an operating system (OS) running on the computer based on the instructions of the program code. It goes without saying that a case where a part or all of the actual processing is performed and the function of the above-described embodiment is realized by the processing is also included.

Further, after the program code read from the storage medium is written in a memory provided in a function expansion card inserted into the computer or a function expansion unit connected to the computer, the program code is read based on the instruction of the program code. Needless to say, the CPU included in the function expansion card or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

When the present invention is applied to the storage medium, the storage medium can store, for example, program codes corresponding to the above-described flowcharts (shown in FIGS. 2, 8 to 10). .

[0082]

As described above, according to the present invention, it is possible to realize an information search corresponding to the limitation of the display amount of the search result and the like.

[Brief description of the drawings]

FIG. 1 is a block diagram of an information search device A according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a flow of an information search process executed in the information search device A.

FIG. 3 is a diagram showing an example of a screen for inputting a search character string.

FIG. 4 is a diagram illustrating a result obtained by performing a morphological analysis on a character string “Kyoto Garden”.

FIG. 5 is a diagram showing a result obtained by executing a morphological analysis and a syntax analysis on a character string “Walk in a garden in Kyoto”.

FIG. 6 is a diagram illustrating an example of index information.

FIG. 7 is a diagram illustrating an example of index information.

FIG. 8 is a flowchart illustrating an information search process.

FIG. 9 is a flowchart illustrating an outline of a character string extraction process.

FIG. 10 is a flowchart illustrating a specific example of a character string extraction process.

FIG. 11 is a diagram showing an example of a search result display screen.

Claims (17)

[Claims] 1. A means for obtaining a document indicating the contents of information to be searched, a search means for searching information related to a search character string given as a search condition among the information, and the search character string Word extracting means for extracting a word included in the document; and a character string extracting means for extracting a character string included in the document relating to the searched information within a preset number of characters. The string extracting means extracts the character string so as to include at least one word that is relevant to the word extracted from the search character string among the words included in the document. Information retrieval system. 2. The information retrieval system according to claim 1, further comprising display means for displaying the extracted character string. 3. The information search system according to claim 2, wherein the display unit displays the extracted character string in a list format for each piece of the searched information. 4. The apparatus according to claim 1, wherein the character string extracting unit extracts a series of character strings included in the document.
Information retrieval system described in. 5. The information search system according to claim 1, wherein the relevant word is the same word as a word extracted from the search character string. 6. The information retrieval system according to claim 1, wherein the document includes a keyword, a summary sentence, or an explanatory sentence indicating the content of the information. 7. The character string extracting unit may include, within the range of the number of characters, a word included in the document so as to include a word having a syntactically constant relationship with the relevant word. 2. The method according to claim 1, wherein the character string is extracted.
Information retrieval system described in. 8. The character string extracting means, for calculating the number of characters in a character string including the relevant word and the syntactically constant word among the character strings included in the document. Means for determining whether or not the calculated number of characters is within the range of the preset number of characters. If it is determined that the number of characters is not within the range of the number of characters, the syntax is fixed. The information retrieval system according to claim 7, wherein the series of character strings that do not include a word are extracted. 9. The information retrieval system according to claim 7, wherein the words having a certain syntactic relationship are words that syntactically negate the relevant word. 10. When there are a plurality of related words, the character string extracting means assigns a priority to each of the related words, and assigns a priority to the word having the highest priority. The information search system according to claim 1, wherein the character string including the essential word is extracted. 11. The information according to claim 11, wherein the priority order is determined based on a part of speech of the relevant word or a syntactical relationship between the relevant words. Search system. 12. The character string extracting means extracts the character string including the essential word and other related words in accordance with the priority in the range of the number of characters. The information retrieval system according to claim 10. 13. The character string extracting unit calculates the number of characters of a character string in the document including the essential word and the word having the highest priority among other relevant words. Means for determining whether or not the calculated number of characters is within the range of the number of characters. If it is determined that the calculated number of characters is not within the range of the number of characters, the calculated number of characters includes the other relevant words. The information retrieval system according to claim 10, wherein a character string that does not exist is extracted. 14. The character string extracting means extracts the character string within the range of the number of characters so that at least one of the first and last characters of the character string is syntactically delimited. The information retrieval system according to claim 1, wherein: 15. The information retrieval system, comprising: a first computer and a second computer communicably connected to each other via a network, wherein the first computer has the retrieval character string. , A means for providing the input search character string to the second computer, and a display means, wherein the second computer is provided from the first computer. 3. The information according to claim 2, further comprising: means for obtaining a search character string; means for obtaining the document; the search means; the word extraction means; and the character string extraction means. Search system. 16. A step of obtaining a document indicating the content of the information to be searched, a step of searching for information related to a search character string given as a search condition among the information, A step of extracting included words; and a step of extracting a character string included in the document relating to the retrieved information within a preset number of characters. In the information search method, among the words included in the document, the character string is extracted so as to include at least one word relevant to the word extracted from the search character string. . 17. A computer, comprising: means for obtaining a document indicating the content of information to be searched; search means for searching, among the information, information related to a search character string given as a search condition; A program for functioning as word extracting means for extracting words included in a string, and character string extracting means for extracting a character string included in the document relating to the searched information within a preset number of characters. The character string extracting means, wherein the character string extracting means includes at least one of words included in the document that is related to a word extracted from the search character string. A recording medium for extracting a column.