Software Engineering: Introduction - Chapter 1

• Software engineering taught at the Faculty of Computers and Artificial Intelligence, Menoufia University, by Dr. Mohamed Gaber Malhat.
• Midterm is worth 20 points.
• Sections are worth 15 points.
• Assignments are worth 15 points.
• Final Exam is worth 50 points.
• Chapter 1 serves as an introduction.
• Chapter 2 discusses software processes.
• Chapter 3 covers agile software development.
• Chapter 4 addresses requirements engineering.
• Chapter 5 is about system modeling.
• Chapter 6 focuses on architectural design.
• Chapter 7 deals with design and implementation.
• Chapter 8 is dedicated to software testing.
• Chapter 9 centres around software evolution.

Introduction: Chapter 1 Agenda

• Chapter 1 introduces definitions and questions related to software.
• Software development, diversity, ethics and the web fall under chapter 1.
• Also includes case studies.

Important Definitions and Questions

• Software consists of computer programs and associated documentation.
• Software products are made for specific customers or a general market.
• Software engineering is an engineering discipline focused on software production.
• Fundamental software engineering activities/processes are software specification, development, validation, and evolution.
• Key challenges facing software engineering: increasing diversity, reduced delivery times, and developing trust.
• Approximately 60% of software costs are development costs.
• The other 40% are testing costs.
• Different techniques suit different system types; prototypes are for games, complete specifications are for safety-critical systems.

Software Products

• There are two types of software products: generic and customized.
• Generic products are ready-to-use systems marketed to any customer.
• Customized products are commissioned by specific customers to meet their needs.
• Software developer owns the specification of generic products and decision of future changes.
• The customer owns the specification of customized product and any future change decisions.

Qualities of Good Software

• Maintainability allows software to evolve with changing customer needs, crucial for adapting to business changes.
• Dependability and security include reliability, security, and safety, preventing physical or economic damage.
• Efficiency avoids wasting system resources like memory and processor cycles, focusing on responsiveness and resource utilization.
• Acceptability ensures software is understandable, usable, and compatible for its target users and other systems.

Software Engineering Explained

• Software engineering is an engineering discipline to ensure all aspects of software production are met.
• It ensures that appropriate theories and methods are used to solve problems that faces software production.
• It's more than just development, encompassing project management and tool development for software production.

Software Activities/Processes

• Software specification involves defining software requirements and constraints with customers and engineers.
• Software development includes designing and programming.
• Software validation involves checking that the completed software meets customer requirements.
• Software evolution includes modifying the software to adapt to changing customer needs and market demands.

Software Engineering Diversity

• Software engineering methods and techniques vary based on the organization developing the software.
• The above also depends on software type and the development team.
• The type of software being developed is the most significant factor.
• Different application types include Stand-alone, interactive transaction based, Embedded system, Batch processing, Entertainment systems, Simulation, Data Collection, and Systems of systems.

Software Engineering on the Web

• The web is platform for application, facilitating web-based systems over local setups.
• Easier and cheaper to change/upgrade software due to no need to install in PCs.
• Web-based system result in reduces costs because one application used by many users.
• Additionally, web based systems are easy to manage.
• The next stage of web-based system dev is web services.
• Web services are software components delivering specific function and accessed on the web.
• Web services ofter provided by different companies are integrated to make a completed application.
• An application that is whole web service is known as 'software as a service'.

Software Engineering Ethics

• Ethical software engineering involves wider responsibilities beyond just technical skills.
• Issues include confidentiality, competence, intellectual property rights, and avoiding computer misuse.
• Ethical engineers must act honestly, and responsibly to earn professional respect.
• According to the ACM/IEEE Code of Ethics, software engineers must act in the public interest.
• They should also act in the best interest of clients/employers, and ensure products meet high standards.
• It emphasizes maintaining integrity, promoting ethical management, advancing the profession's integrity.
• It includes being fair to colleagues, participating in lifelong learning.

Chapter 1 Case Studies

• A few real world case studies include are used to exemplify concepts.

Insulin Pump Control System: Case Study

• The insulin pump is an embedded system for diabetics to control blood glucose (an artificial pancreas).
• It is a safety-critical system where low blood sugar can cause brain malfunction, coma, and death.
• High blood sugar levels can cause eye and kidney damage.
• The first requirement demands system to be available 24/7 to deliver insulin when required.
• The second requirement demands system to reliably deliver the correct insulin amount to counteract current blood sugar levels.
• All insulin doses must be recorded and analyzed.
• Therefore it must be designed and implemented to always meet these requirements.

Mental Healthcare Patient Management: Case Study

• It is a medical information system that maintains information about patients suffering from mental health problems.
• It also maintains all patients treatments
• Clinicians can create, edit, and view records for patients.
• System monitors records of patients in treatment and issues warnings if problems arise.
• Regular specialist visits needed to manage and handle the patients with problems.
• Monthly management reports showing treated patients, clinic attendance, drugs prescribed, and their costs.
• The system concerns are patient privacy, and safety (suicidal dangers).

Wilderness Weather Station: Case Study

• Data collection system in remote areas that collects data about weather conditions.
• Collects temperature, pressure, sunshine, rainfall, wind speed, and wind direction.
• The weather station is connected to databased for archiving.
• It also included regular station maintenance
• Requirements include monitoring power, also reporting faults from instruments.
• Batteries are charged whenever environmental conditions allow.
• The system supports dynamic reconfiguration with new software and backup instruments post system failure.