august 13, 2015 1 august 13, 2015august 13, 2015august 13, 2015 azusa, ca sheldon x. liang ph. d....

April 19, 20231

April 19, 2023April 19, 2023 Azusa, CAAzusa, CA

Sheldon X. Liang Ph. D.

Software Engineering Software Engineering in CS in CS at at APUAPU

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

CS 470 Software Engineering ICS 470 Software Engineering I

April 19, 20232

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

CS 470 (SE)CS 470 (SE)22

April 19, 20233

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What is a system What is systems engineering What is systems engineering process What we learn from systems engineering

Break down: Problem Definition (PRD)

Model&Interface: Problem Design (SDD)

Unit coding: Programming (SPP)

Put-together: Integration (SIP)

What we are going to do with DFD

April 19, 20234

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What is a systemComponents - A purposeful collection of inter-related components working together to achieve some common objective.

External Entities - A system may include software, mechanical, electrical and electronic hardware and be operated by people.

External Dependencies - System components are dependent on other system components

Collaboration - The properties and behavior of system components are inextricably intermingled

problem requirements definition: identification of data & operation

April 19, 20235

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What is systems engineering

Systems Engineering (SE) is an interdisciplinary field of engineering, that focuses on the development and organization of complex artificial systems.

Systems Engineering integrates other disciplines and specialty groups into a team effort, forming a structured development process that proceeds from concept to production to operation and disposal.

Systems Engineering considers both the business and the technical needs of all customers, with the goal of providing a quality product that meets the user needs

Structured development process: Analysis vs Synthesis

April 19, 20236

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What is systems engineering process

April 19, 20237

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What we learn from systems engineering

Break down: Problem Definition (PRD)

Model&Interface: Problem Design (SDD)

Unit coding: Programming (SPP)

Put-together: Integration (SIP)

April 19, 20238

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What we learn from systems engineering

April 19, 20239

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What we learn from systems engineering

VV

April 19, 202310

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What we learn from systems engineering

VVFrom Conceptual to Complete

From break-down to put-together

April 19, 202311

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What we learn from systems engineering

VRequirement Analysis

Functional Analysis/Allocation

Integration / Synthesis

April 19, 202312

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What we learn from systems engineering

VRequirement Analysis

Functional Analysis

Functional Allocation

Problem Definition (PRD)-- Identify external entities-- identify major components -- identify links (dataflow)

Problem Design (SDD)-- functional allocation -- activities & interface-- identify further components -- identify links

PRD & SDD

April 19, 202313

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What we’re going to do with DFD

VV

April 19, 202314

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What we’re going to do with DFD

V

April 19, 202315

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What we’re going to do with DFD

PRD:-- External Entities Customer Keypad Card Reader Control System Customer Display Printout Dispenser Cash Dispenser

-- Functional Level-0 Auto Teller System

April 19, 202316

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What we’re going to do with DFD

VPRD (Refined):-- External Entities-- Functional Level-1 Receive operator command Verify PIN from card Display customer options Prepare command Update display Prepare message Prepare printout Mange withdrawal

April 19, 202317

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What we’re going to do with DFD

VSDD (description):The CheckPIN procedure handles the verification of the customer's Personal Identification Number (PIN) using data retrieved from the card's magnetic strip. The procedure invites the customer to enter their PIN using the keypad. If this does not match the PIN stored on the card, a limited number of retries is permitted, after which the card is confiscated as a security precaution. If the correct PIN is entered, the Services procedure is called.

April 19, 202318

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What we’re going to do with DFD

VSDD (pseudo-code):PROCEDURE CheckPINCONSTANTS MAXPINS IS 3VARIABLES PINCounter IS NUMBERBEGIN read data from card set PINCounter to zero LOOP UNTIL PINCounter is equal to MAXPINS input PIN from customer keypad IF entered PIN matches card PIN THEN EXITLOOP ENDIF add 1 to PINCounter ENDLOOP IF PINCounter is equal to MAXPINS THEN confiscate customer's card ELSE CALL PROCEDURE Services ENDIFEND CheckPIN

April 19, 202319

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering

What we’re going to do with DFD

Problem Requirements Definition (PRD)

PRD0 = Major_Operation + ∑ External_entities

PRD* = ∑ Functional_allocation (tasks) + ∑ Dataflows

Software Design Document (SDD)

SDD = ∑ Functional_Description (strategic psuedo-code)

Software Project Plan

SPP = ∑ Scheduled Implementation (coding & testing plan)

April 19, 202320

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering What we’re going to do with DFD

Data Pool

Op1 Fun2 Op3 Fun4

Program = DataStructure + Algorithm:/* Data Pool */ … …void Op1 (… …) {}int Fun2 (… …){}void Op3 (… …){}float Fun4 (… …){}

int main (){ … …}

Thank you very much!

Questions?

April 19, 202321

Azusa Pacific University, Azusa, CA 91702, Tel: (800) 825-5278 Department of Computer Science, http://www.apu.edu/clas/computerscience/

Software Engineering Software Engineering in CS in CS at at APUAPU

(SE)(SE)22: System Engineering vs Software Engineering: System Engineering vs Software Engineering