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Data ManagementData ManagementFor Scientific Research

Stanza

Session 3: Systems Analysis and DesignSession 3: Systems Analysis and Design

Image:

Systems Development Life Cycle (SDLC)Systems Development Life Cycle (SDLC)

One of several approaches to systems development is the ,also called the “Waterfall” model.

SDLC

Peter Kemp / Paul Smith / Wikimedia

SDLC Activities and ArtifactsSDLC Activities and ArtifactsPhase Activities Artifacts1

Planning2 Define purpose, scope, options, costs3 Go/No-Go Decision, Plan

Systems Analysis Process Modeling, Requirements Anal. Diagrams4, Requirements

Systems Design Interface & Data Modeling Diagrams5, DD6, Schema

Development Acquisition and/or Coding, Integration Working System

Testing Testing, Bug Reports & Fixes Validated System

Deployment Installation, Training, Launch Production System

Maintenance Backups, Upgrades Maintained System

Evaluation Effectiveness7 and Cost Checks Evaluation Report

Disposal System Removal, Archival, and Surplus Archived Artifacts

(See the next slide for notes.)

SDLC Activities and ArtifactsSDLC Activities and ArtifactsNotes

1 There are of potential from each phase.

2 The may also be called the preliminary investigation, system

investigation, feasibility study, or project initiation phase, among other names.

3 Determination of options and costs (in the ) is often referred to,

specifically, as a .

4 may produce , , (DFD),

and diagrams.

5 may produce (ER) diagrams and UML diagrams.

6 As a systems design artifact, DD represents a document.

7 The will have numerous measures of .

dozens artifacts

planning phase

planning phase

feasibility study

Systems analysis flow charts swim lanes data flow diagrams

UML

Systems design Entity-relationship

Data Dictionary

Evaluation phase effectiveness

An Example Research ProjectAn Example Research Project

Let's imagine that we are to conduct a research study like this:

We will sample various surfaces for bacteria.

Some of those surfaces will be on human subjects.

We will analyze the bacteria samples in the lab.

Test results will be entered into a data system.

We will perform statistical analyses on the test results.

Goals ListGoals List

The stakeholder goals for system, in “verb noun” form are:

Role Goal

Subject Sign Consent Form

Sampler Collect Consent Form

Subject Complete Subject Form

Sampler Collect Subject Form

Sampler Collect Sample

Sampler Deliver Sample

Lab Tech Test Sample

Lab Tech Dispose Sample

Statistician Analyze Results

Structured NarrativesStructured Narratives

From this goals list, we can create use case diagrams and astructured narrative. A structured narrative is a description

which conforms to some sort of standardized format.

For the purposes of our preliminary investigation, we will justadd one-sentence descriptions for each goal in our list. Ourdescription will use terms such as “if”, “must” or “may” and

phrases like “for each” or “for all”.

This simple structure will allow us to develop a process modelusing various types of diagrams. From our process model, we will

develop a data model.

Structured Narrative: Part 1, Subject DataStructured Narrative: Part 1, Subject DataActor Use Case Description

Subject Sign Consent Form If a human subject is sampled, the subject must sign a

consent form.

Sampler Collect Consent

Form

The sampler must collect the consent form before

sampling the subject.

Subject Complete Subject

Data Form

The subject must complete a subject data form by

providing personal information.

Sampler Collect Subject Data

Form

The sampler must collect the subject data form

before sampling the subject.

Structured Narrative: Part 2, SamplingStructured Narrative: Part 2, SamplingActor Use Case Description

Sampler Enter Subject

Data

The sampler must enter subject information into the

system for each human subject sampled.

Sampler Collect Sample The sampler may collect a sample from a human subject

or from a non-human surface.

Sampler Record Geo

Location

The sampler must record the geographical sampling

location for all samples taken.

Sampler Record Body

Location

The sampler must record the human body sampling

location for all samples taken from human subjects.

Sampler Record

Temperature

The sampler must record a temperature reading for all

samples taken.

Sampler Record Humidity The sampler must record a humidity reading for all

samples taken.

Sampler Enter Sample

Data

The sampler must enter sample information into the

system for each sample collected.

Sampler Deliver Sample The sampler must deliver the sample to the laboratory.

Structured Narrative: Part 3, AnalysisStructured Narrative: Part 3, AnalysisActor Use Case Description

Lab Tech Receive

Sample

The laboratory technician must receive the sample when

it is delivered.

Lab Tech Store Sample The laboratory technician must store the sample in a

cooler (refrigerator).

Lab Tech Split Sample The laboratory technician must split the sample before

testing.

Lab Tech Test Sample The laboratory technician must test the sample before it

expires.

Lab Tech Enter Test

Result

The laboratory technician must enter the test result into

the system.

Lab Tech Dispose

Sample

The laboratory technician must dispose of the sample

after it is no longer needed.

Statistician Query

Results

The statistician may query the system for test results.

Statistician Analyze The statistician may analyze the results using statistical

Actor Use Case Description

Results tools.

Use Case NarrativesUse Case Narratives

For even more clarity, one can also develop ,which go into far greater detail. This level of detail might be

useful in later design phases.

use case narratives

Image: UI CyberGIS Project

UseUseCase Diagrams: Project OverviewCase Diagrams: Project Overview

This diagram shows the actors and their project goals.

Use Case Diagrams: More Detailed ViewUse Case Diagrams: More Detailed View

This diagram shows a more detailed view of the actors and theirproject goals.

Flow ChartsFlow Charts

To better elucidate process branching in a system, we can use aflow chart. Here is a closer look at the sampling process.

Swim Lane DiagramsSwim Lane Diagrams

This swim lane diagram shows an overview of the system. Thelanes not only show actors, but also sequence and outputs.

Data Flow DiagramsData Flow Diagrams

Context Diagrams (Level 0)

Data Flow Diagrams (Level 1 and higher)

Context Diagram with Gane/Sarson Symbols

Context Diagram with Yourdon/DeMarco Symbols andCurved Lines

Context Diagram with Yourdon/DeMarco Symbols withoutSubject Entity

Level 1 Data Flow Diagram

Level 1 Data Flow Diagram with Curved Lines

Level 1 Data Flow Diagram without Subject Entity

Context Diagram (Gane/Sarson Symbols)Context Diagram (Gane/Sarson Symbols)

Context Diagram (Yourdon/DeMarco)Context Diagram (Yourdon/DeMarco)

Context Diagram: Without Subject EntityContext Diagram: Without Subject Entity

Level 1 Data Flow DiagramLevel 1 Data Flow Diagram

Level 1 DFD ... with Curved LinesLevel 1 DFD ... with Curved Lines

Level 1 DFD ... Without Subject EntityLevel 1 DFD ... Without Subject Entity

Hands-on Group ExerciseHands-on Group Exercise

Working as a group, with a pen or pencil and paper, make somesystems analysis diagrams. Sticky notes, a whiteboard, etc. may

be helpful when brainstorming and designing the diagrams.

Photo: SarahStierch / Wikimedia

Hands-onHands-onGroup Exer‐Group Exer‐cise: Varia‐cise: Varia‐

tionstionsData Flow Diagrams

Transform your use casediagram(s) into a contextdiagram and level 1 DFD,

especially if there are manydata processing steps or data

sources. Diagram furtherlevels (time permitting).

Flow Charts and Swim Lanes

Alternatively, if there arecomplex decisions, branching,

or multiple entities performingvarious actions, then make a

flow chart or swim lanediagram from your use case

diagram(s).

Graphic:

DiscussionDiscussion

Explain your diagrams to the group as though you werepresenting your data system requirements to those who wouldbuild the data system. Ask questions that a system implementer

might ask, especially where there are ambiguities.

Jagbirlehl / Wikimedia

In the Coming Sessions...In the Coming Sessions...Entity-Relationship Diagrams

MySQL Workbench

Building Database Tables

Database Applications

Action Items (videos, readings, and tasks)Action Items (videos, readings, and tasks)

textbook: Chapter5. Handling Text in the Shell

Skim: Wikipedia: , , and

Explore: , ,

Optional- Skim: textbook: Chapters 3-4

Create enough diagrams to describe your system “unambiguously”

Post your system documents and diagrams in your project wiki

Organize your material into a “Requirements Document” wiki page

Refer to the in the “Data Management” project wiki

Conceptual Data Modeling

Defining table relationships

Databases and SQL

ERD Training

PCfB

Req. anal. DB design, E-R model normalization

UW Privacy SA Wiki BA Guidebook

RDDaI3CE

example

See AlsoSee AlsoRapid application development

Creately - Ultimate Flowchart Guide

Traditional vs Modern Flowcharts

DFD over Flowcharts PDF

DFD Slideshow

Creately DFD

DFDs - and follow link to “Article”

UML Data Modeling Video

Graphical Data Flow Programming in LabVIEW Video

Image: / Wikimedia

Questions and CommentsQuestions and Comments

© Nevit Dilmen

Some Parting WordsSome Parting Words

–

Source: Empirical Model-Building and Response Surfaces (1987), p.424. ( .)

Essentially, all models are wrong, but some are useful.

George E. P. Box

Wikiquote

Source: Camille Flammarion / Wikimedia