Designing is the most important phase of software development. It requires

Transcription

1 Chapter 7 System Design Designing is the most important phase of software development. It requires careful planning and thinking on the part of system designer. Designing software means to plan how the various parts of the software are going to achieve the desired goal. It should be done with utmost care because if this phase contains any error then that will affect the performance of the system, as a result it may take more processing time, more response time, extra coding workload etc. 7.1 System Design The purpose of the design phase is to plan a solution to the problem specified requirements document. This is the first phase, moving from problem domain to solution domain. The design process is a set of iterative steps that enable the designer to describe all the aspects of the software to be built. Design is essentially the bridge between requirement specification and final solution for satisfying the requirement. The design of a system is essentially a blueprint or a plan for the solution of a problem by the system. Here we consider a system to be a set of components with clearly defined behaviour that interacts with Health Information Management 105 MCOAHS, Manipal

2 each other in fixed defined manner to produce some behaviour or services for its environment Modular Description Figure 7.1: Modular Structure of OncoSys Breast Cancer This module is used to record information from Breast Cancer patients. It provides for both view & capturing patient information, medication & therapies given. Recording Information: Input: Hospital Registration Number (HRN) Processing: Validate HRN & check if current visit details. Validate forms filled and store in database Output: Display filled information in read only manner On button click() If(Patient visited today or patient is In patient) Health Information Management 106 MCOAHS, Manipal

3 If(required field is empty) Display error message & cancel further processing Else Display filled information Displaying Information: Input: Hospital Registration Number (HRN), Visit Date Processing: Validate HRN Output: Display all therapies and Medications done on Visit Date On button click() If(HRN & visit Date is valid) Display recorded information on specific date Else Display error message Health Information Management 107 MCOAHS, Manipal

4 Cervical Cancer This module is used to record information from Cervical Cancer patients. It provides both view & capturing patient information, medication & therapies given. Recording Information: Input: Hospital Registration Number (HRN) Processing: Validate HRN & check if current visit details. Validate forms filled and store in database Output: Display filled information in read only manner On button click() If(Patient visited today or patient is In patient) If(required field is empty) Display error message & cancel further processing Else Display filled information Displaying Information: Input: Hospital Registration Number (HRN), Visit Date Health Information Management 108 MCOAHS, Manipal

5 Processing: Validate HRN Output: Display all therapies and Medications done on Visit Date On button click() If(HRN & visit Date is valid) Display recorded information on specific date Else Display error message Knowledge Base Figure 7.2: Modular Structure of Knowledge Base Add Website This modules takes url as base and starts the crawler. It requests and downloads a copy of the document available at this url. It extracts the text and Health Information Management 109 MCOAHS, Manipal

6 indexes the contents. Input: URL, Depth Level Processing: Validate URL and send URL with Depth Level to the search engine as seed and starts the crawler until indexing is competed. Output: Indexing complete Message On button click() If(Upload) If(Any field is empty) Display error message and cancel crawler Else Display Indexing Complete Message Add Files This module is used at the time of adding knowledge in local server. Proper validation is done on both client and server side for file types to be uploaded. It allows only those files which can be indexed. Input: Title, Description, File Path Processing: Upload file to local server after validation is performed for maximum words limit on input box and all the details are stored in the database. Health Information Management 110 MCOAHS, Manipal

7 Output: File is sent for indexing and result is shown back On button click() If(Upload) If(Any field is empty) Display error message and cancel upload / indexing Else Upload the file and index its contents Add Notes This module provides notes or article writing facility to physicians. They can write articles in well a formatted manner. It adds as offline content which can be searched by the user. Input: Title, Description, Content Processing: Validate Title, Description, Content and store in database Output: Notes added On button click() Health Information Management 111 MCOAHS, Manipal

8 If(Save Notes) If(Any field is empty) Display error message without saving Else Display notes saved message Text Message It provides messaging facility to the physicians. Any physician can send and receive textual messages from other physicians registered in the system. Input: To Username, Content Processing: Validate content length and store in database. Output: Message sent On button click() If(Send) If(Any field is empty) Display error message and cancel message Health Information Management 112 MCOAHS, Manipal

9 Else Display result as sent Search Engine It provides the facility to search the given keyword from the index stored. In case of multiple keywords AND rule is used i.e. documents with all the words will be provided. Input: Keyword, Order By, Search Type Processing: Split the keyword if more than one word and search each keyword. Order the results by rank or as Order By input. Output: Search results in ordered manner On button click() If(Search) If(Search key is empty) Display error message and cancel search Else Health Information Management 113 MCOAHS, Manipal

10 Display search result Case Base This module provides statistical charts generated from the information available in HIS database of hospital. It provides an overview of patient s information over a period of time. Input: From Date, To Date Processing: Validate date and display various statistics retrieved from HIS Output: Graphical Chart showing statistics On button click() If(OK) If(FromDate IsLessThan ToDate) Generate chart and display them Else Display error message Health Information Management 114 MCOAHS, Manipal

11 7.2 Preliminary Design Entity Relationship Diagram Figure 7.3: ER Diagram 1 Health Information Management 115 MCOAHS, Manipal

12 Figure 7.4: ER Diagram 2 Figure 7.5: ER Diagram 3 Health Information Management 116 MCOAHS, Manipal

13 Figure 7.6: ER Diagram 4 Figure 7.7: ER Diagram 5 Figure 7.8: ER Diagram 6 Health Information Management 117 MCOAHS, Manipal

14 Figure 7.9: ER Diagram 7 Figure 7.10: ER Diagram 8 Health Information Management 118 MCOAHS, Manipal

15 Figure 7.11: ER Diagram 9 Health Information Management 119 MCOAHS, Manipal

16 7.2.2 System Architecture Figure 7.12: System Architecture 1 Health Information Management 120 MCOAHS, Manipal

17 Figure 7.13: System Architecture 2 Health Information Management 121 MCOAHS, Manipal

18 7.3 Detailed Design Schema Diagram Figure 7.14: Schema Diagram 1 Health Information Management 122 MCOAHS, Manipal

19 Figure 7.15: Schema Diagram 2 Health Information Management 123 MCOAHS, Manipal

20 Figure 7.16: Schema Diagram 3 Health Information Management 124 MCOAHS, Manipal

21 Figure 7.17: Schema Diagram 4 Health Information Management 125 MCOAHS, Manipal

22 Figure 7.18: Schema Diagram 5 Figure 7.19: Schema Diagram 6 Health Information Management 126 MCOAHS, Manipal

23 7.3.2 Table Structure Demographic ID uniqueidentifier NOT NULL HRN varchar(16) PRIMARY KEY DORRI datetime NOT NULL Diagnosis Date datetime NULL Cancer Type varchar(8) NULL Patient Name varchar(32) NOT NULL Father Name varchar(32) NOT NULL HWM Name varchar(32) NULL Caretaker Name varchar(32) NOT NULL Local Address varchar(256) NOT NULL Local State varchar(32) NOT NULL Permanent Address varchar(256) NOT NULL Permanent State varchar(32) NOT NULL Contact Number varchar(32) NOT NULL Duration Stay smallint NULL DOB datetime NOT NULL Sex char(1) NOT NULL Marital Status char(1) NOT NULL Religion varchar(64) NULL ID varchar(32) NULL Photo varibnary(max) NULL ContentType varchar(16) NULL Table 7.1: Demographic Table Health Information Management 127 MCOAHS, Manipal

24 Visit VisitID uniqueidentifier PRIMARY KEY HRN varchar(16) NOT NULL Date datetime NOT NULL InPatient bit NOTNULL Discharged bit NOT NULL Table 7.2: Visit Table User Profile UserId uniqueidentifier NOT NULL UserName varchar(256) PRIMARY KEY FirstName varchar(16) NULL LastName varchar(16) NULL Gender char(1) NULL Birthday datetime NULL SecurityQuestion varchar(64) NULL SecurityAnswer varchar(32) NULL Photo varbinary(max) NULL ContentType varchar(16) NULL Table 7.3: User Profile Table Health Information Management 128 MCOAHS, Manipal

25 Attending Doctor VisitID uniqueidentifier PRIMARY KEY Name nvarchar(256) PRIMARY KEY Table 7.4: Attending Doctor Table FilesIn FileID int Primary key URL varchar(1024) NOT NULL Title varchar(256) NOT NULL Description varchar(512) NOT NULL CrawledDate datetime NOT NULL Size bigint NOT NULL Mime varchar(150) NOT NULL Extension varchar(64) NOT NULL Username nvarchar(256) NOT NULL IsLocal bit NOT NULL Table 7.5: FilesIn Table Index FileID int Primary key Word varchar(256) Primary Key Position smallint NOT NULL Count smallint NOT NULL Table 7.6: Index Table Health Information Management 129 MCOAHS, Manipal

26 Notes NotesID int Primary key WrittenBy nvarchar(256) Primary Key DateWritten datetime NOT NULL Title varchar(256) NOT NULL Decription varchar(512) NOT NULL Content varchar(max) NOT NULL Path varchar(1024) NOT NULL Table 7.7: Notes Table Message MessageID int Primary key From nvarchar(256) NOT NULL To nvarchar(256) NOT NULL DateSent datetime NOT NULL Title varchar(256) NOT NULL Content varchar(512) NOT NULL SndDeleted bit NULL RecDeleted bit NULL Table 7.8: Message Table Health Information Management 130 MCOAHS, Manipal

27 DeadLinks FileID int Primary key ReportedBy nvarchar(256) Primary key Table 7.9: DeadLinks Table Rating FileID int Primary key RatedBy nvarchar(256) Primary key Score tinyint NOT NULL Table 7.10: Rating Table Health Information Management 131 MCOAHS, Manipal

28 7.3.3 Data Flow Diagram DFD Context Diagram Figure 7.20: DFD Context Diagram Health Information Management 132 MCOAHS, Manipal

29 Figure 7.21: Physician - DFD Level 1 Health Information Management 133 MCOAHS, Manipal

30 Figure 7.22: Administrator - DFD Level 1 Health Information Management 134 MCOAHS, Manipal

31 Figure 7.23: DFD Level 2(a) Health Information Management 135 MCOAHS, Manipal

32 Figure 7.24: DFD Level 2(b) Process Description Detail description of the processes in DFD is given below. Process ID Process Name Description 1 General Report It generates statistical report from the data available in Patient Information System 2 Process Patient Info It Adds/Deletes Patient Diagnosis and Medication done during patient visit to hospital 3 Process FilesIn It Adds/Deletes Files uploaded or files crawled by a user 4 Crawler It starts crawling the page seeded and indexes its contents Health Information Management 136 MCOAHS, Manipal

33 5 Process Dead It reports dead links or broken Links / Rating links to administrator. the rating given by user It saves 6 Process Notes It adds/deletes notes written 7 Process Message It adds/deletes Messages sent and received 8 Search Engine It searches the keyword from index and send the results back to user 9 Check out UsersList It retrieves users list from database and allows enabling/disabling user 10 Check out Dead Links It retrieves all dead links reported by user Table 7.11: Process Description Process ID Process Name Description 4.1 Web Crawling It reads and writes settings for the crawler. It downloads pages as a temporary file in local server 4.2 Text Extracting It reads the contents of temporary files downloaded and extracts texts from them 4.3 Create Index It parses the extracted text and splits them into Words Health Information Management 137 MCOAHS, Manipal

34 4.4 Rank Words It calculates the rank for each word and stores them Table 7.12: Sub-Process Description 1 Process ID Process Name Description 8.1 Search Query Analyzing It takes the search queries and splits them into Words 8.2 Searching It searches for each partition of the query from Index and FilesIn table 8.3 Search Result Ordering It rearranges the order of search results by their rank or preferences 8.4 Results Status Checking It checks if the results are already rated or reported dead by the current user Table 7.13: Sub-Process Description 2 Health Information Management 138 MCOAHS, Manipal

35 7.3.4 Search Engine Classes Figure 7.25: Crawler Class Health Information Management 139 MCOAHS, Manipal

36 Figure 7.26: Document Classes Figure 7.27: Searcher Classes Health Information Management 140 MCOAHS, Manipal

37 Figure 7.28: Common Classes Health Information Management 141 MCOAHS, Manipal

38 7.3.5 Search Engine Methodology Generally speaking the search engine can be divided into two major modules: Spider module and Query module. Spider module will be accessible to all physicians. It takes start page URL as base to spider and index contents in database to search later. It parses the documents contents based on requirement. Query module gets queries from physicians; it performs a search action and finally returns the output as search results back to physicians Robots Exclusion Sometimes people find their web sites have been indexed (traveled their site and obtained the contents) by an indexing robot (web crawler) or that resource discovery robot has visited part of the site that for some reason shouldn t be visited by robots. In recognition to this many Web Robots offer facilities for Website administrators and content providers to limit what the robot does. This is achieved through two mechanisms: The Robots Exclusion Protocol: A Web site administrator can indicate which parts of the site should not be visited by a robot, by providing a specially formatted file on their site, in For example: (actually, the /robots.txt file usually contains a record looking like this) User-agent: * Disallow: /cgi-bin/ Disallow: /tmp/ Health Information Management 142 MCOAHS, Manipal

39 Disallow: /~andy/ In this example, three directories are excluded (disallow). Note that you need a separate Disallow line for every URL prefix to exclude. Also, one may not have blank lines in a record, as they are used to delimit multiple records. The * in the User-agent field is a special value meaning any robot. Specifically, you cannot have lines like Disallow:/tmp/* or Disallow: *.gif The Robots META tag : A Web author can indicate if a page may or may not be indexed, or analyzed for links, through the use of a special HTML META tag. For example, <META NAME="ROBOTS" CONTENT="NOINDEX, NOFOLLOW"> A robot should neither index this document, nor analyze it for links Web Crawler A web crawler is a program that systematically fetches web pages. Web crawlers are also known as ants, automatic indexers, bots, spiders, Web robots, and worms. It can create an index of available Web pages through seeding where a user provides base URL. It is an application that automatically traverses the Web s hypertext structure by retrieving a document, and recursively retrieving all documents that are referenced until the specified scan level is reached. An application that automatically traverses the Web work as follows: A base URL or Web File Path is given as a starting point. Health Information Management 143 MCOAHS, Manipal

40 The Web crawler retrieves the first page and adds an entry for this page in the index. Since the web is a hyperlinked environment, these pages might have links to various other pages on various other Web servers. Then, it adds each of the hyperlinks that exist on that Web page to the FIFO queue. It repeats this process of retrieval and recording for each page in its queue in First Come First Serve Order until the specified depth level is reached. Thus, for each page discovered, the list of pages that remain to be gathered keeps growing, and so will the index. In this way Web crawler s indexing process builds upon itself. Figure 7.29: Web Crawler Example The sequence of crawler if 1, 2, 3, 4 to 13 and so on until the Depth level is equal to the level given by the user. Consider Figure:7.29 where a crawler is discovering 13 pages from a single base page moving left to right. Arrows indicate the hyperlink in a page, pointing to another page. This process of automatic page discovery takes a great burden on search engine maintenance Health Information Management 144 MCOAHS, Manipal

41 team. Therefore indexing is limited to a maximum of ten levels and done manually by the user. Moreover to decrease the load on the server, the downloaded documents for indexing are discarded once done. In this project the Crawler authenticates each page on web before it scans them String Splitting Divide a string of more than one word into smaller units. In C# there is built in string class that allows splitting a string into an array of words. For example, string Knowledge base can be broken into Arr[0]=Knowledge Arr[1]=base With this splitting technique, the pages indexed by the crawler are partitioned into tokens. This method is used before ranking Index A table which contains sequence of (key, pointer) pairs where each key is a simple word and pointer points to a record in Files table i.e. file in which it occurs. A search is made on this index for a given word Ranking Ranking is the theory that calculates importance of each word in a page. It is theory that keyword search is based on. The following rule will affect the rank of keyword Position of the keyword in a file Frequency of the keyword in a file Health Information Management 145 MCOAHS, Manipal

42 Therefore a page with keywords occurring at beginning will be ranked higher than the page with keyword in the middle or the end of the page. However this may not be exactly as per expectation all the time. Rank: = Position of keyword - Frequency of keyword in a document The output of ranking is a list of keywords and each has the following information: this keyword url that this key is found rank number indicating the importance of this keyword in a document This information is used in keyword search Search Method Keyword search is used which is the most common and also the fundamental method of search. Ranking of keyword is based on the idea of keyword search, since the concept of keyword search determes which documents are most relevant to the given query (keyword) and ranking is based at this determination. e.g. Search for the keyword cancer, the search engine will search for this word cancer and output the result (url, descriptions) ordered by the rank number in an ascending order. In case of multi-keyword search e.g. breast cancer, keyword search will perform simple AND search. That is the result of search are the url contains these two keywords and order by the sum of the ranks of these two in an ascending order. Health Information Management 146 MCOAHS, Manipal

43 7.3.6 Functional Dependencies Demographic HRN - DORRI, Diagnosis Date, Cancer Type, Patient Name, Father Name, HWM Name, Caretaker Name, Local Address, Local State, Permanent Address, Permanent State Contact Number, Duration Stay, DOB, Sex, Marital Status, Religion, ID, Photo, ContentType Visit VisitID - HRN, Date, InPatient, Discharged Attending Doctor VisitID, Name User Profile UserName - UserId, FirstName, LastName, Gender, Birthday, SecurityQuestion, SecurityAnswer, Photo, ContentType FilesIn FileID - Url, Title, Description, CrawledDate, Size, Mime, Extension, Username, IsLocal Index FileID, Word - Position, Count Notes NotesID, WrittenBy - Title, DateWritten, Description, Content, Path Health Information Management 147 MCOAHS, Manipal

44 Message MessageID, From - DateSent, Content, Title, SndDeleted, RecDeleted DeadLinks FileID, ReportedBy Rating FileID, RatedBy - Score Data Dictionary Seed HIS base URL or start page Hospital Information System Table 7.14: General Data Dictionary Demographic ID HRN DORRI Diagnosis Date Cancer Type Patient Name Father Name HWM Name Caretaker Name Local Address Uniqueidentifier of each row Hospital Registration Number Date of Registration at Reporting Institution Date of Diagnosis Breast or Cervix cancer type Name of patient Patient s Father s name Husband / Wife / Mother name Name of caretakers Local address Health Information Management 148 MCOAHS, Manipal

45 Local State Permanent Address Permanent State Contact Number Duration Stay DOB Sex Marital Status Religion ID Photo ContentType Local state Permanent address Permanent state Contact number of patient Number of Years of stay Date of Birth Gender Single / Married Religion ID Store patient image Image type Table 7.15: Data Dictionary - Demographic Health Information Management 149 MCOAHS, Manipal

46 Visit VisitID HRN Date InPatient Discharged Uniqueidentifier of each visit Hospital Registration Number Date and time of visit In-patient of Out-patient Is discharged (for In-patient) Table 7.16: Data Dictionary - Visit User Profile UserId UserName FirstName LastName Gender Birthday SecurityQuestion SecurityAnswer Photo ContentType Unique user ID User s sign in name First name Last name Gender Date of Birthday Security Question for password retrieval Security Answer for password retrieval User s image Image type Table 7.17: Data Dictionary - User Profile Health Information Management 150 MCOAHS, Manipal

47 Attending Doctor VisitID Name Uniqueidentifier from visit Assigned Doctor name Table 7.18: Data Dictionary - Attending Doctor FilesIn FileID URL Title Description CrawledDate Size Mime Uniqueidentifier of each file URL of file Title of file Description of file Date of Spidering or crawling Total size of file Multipurpose Internet Mail Extension of file contents Extension Username IsLocal File extension / type Uploaded user name Is local file or web Table 7.19: Data Dictionary - FilesIn Health Information Management 151 MCOAHS, Manipal

48 Index FileID Word Position Count Uniqueidentifier of file from FilesIn Sigle word from file Position of word in file Number of same word in file Table 7.20: Data Dictionary - Index Notes NotesID WrittenBy DateWritten Title Decription Content Path Uniqueidentifier of each Notes Written by username Date written Title of Note Description of Note Actual content of Note URL to parse Table 7.21: Data Dictionary - Notes Message MessageID From To DateSent Title Content Uniqueidentifier of each message Sender s name Receiver s name Date and Time Title of message Message content Health Information Management 152 MCOAHS, Manipal

49 SndDeleted RecDeleted Is sender deleted message Is receiver deleted message Table 7.22: Data Dictionary - Message DeadLinks FileID ReportedBy Uniqueidentifier from FilesIn Reported Username Table 7.23: Data Dictionary - DeadLinks Rating FileID RatedBy Score Uniqueidentifier from FilesIn Username rated Number rated Table 7.24: Data Dictionary - Rating Health Information Management 153 MCOAHS, Manipal