Human Factors and Systems Chap 1

Human Factors and Systems  Human Factors Defined    A History of Human Factors    Human Factors Profession    Systems  

Human Factors Defined  Chapanis (1985) ： discover and apply information about discover and apply information about human behavior, abilities, limitations, human behavior, abilities, limitations, and other characteristics and other characteristics to the design of tools, machines, systems, tasks, to the design of tools, machines, systems, tasks, jobs, and environments jobs, and environments for productive, safe, comfortable and effective for productive, safe, comfortable and effective human use. human use.  Focus: human beings and their interaction with human beings and their interaction with 產品、裝置、設備、程序、環境 產品、裝置、設備、程序、環境 改變 things 與環境，使符合人的能力、極限與需求 改變 things 與環境，使符合人的能力、極限與需求

Human Factors Defined  Objectives 1. 增進效果與效率：方便、降低錯誤、提高生產力 1. 增進效果與效率：方便、降低錯誤、提高生產力 2. 增進人類福址：舒適、滿足、提高生活品質 2. 增進人類福址：舒適、滿足、提高生活品質  Approach systematic application of relevant information systematic application of relevant information about 人的能力、極限、特性、行為、動機等 about 人的能力、極限、特性、行為、動機等 to design..... to design..... scientific investigation scientific investigation  Not ： just applying checklists and guidelines just applying checklists and guidelines using oneself as the model using oneself as the model common sense (end) common sense (end)

A History of Human Factors  Early History  : The Birth of a Profession  : A Period of Rapid Growth  : Computers, Disasters, and Litigation （訴訟） and Litigation （訴訟）  1990 and Beyond

A History of Human Factors  Early History Industrial revolutionIndustrial revolution (late 1800s & early 1900s) (late 1800s & early 1900s) Gilbreth & Gilbreth: 外科手術程序Gilbreth & Gilbreth: 外科手術程序 World war IIWorld war II  Fitting the person to the job selection, training selection, training  Fitting the equipment to the person

A History of Human Factors  : The Birth of a Profession 1945: Engineering Psychology Lab.1945: Engineering Psychology Lab. （美國空軍） （美國空軍） 1949: Ergonomics Research Society1949: Ergonomics Research Society 1957: Ergonomics (Journal)1957: Ergonomics (Journal)

A History of Human Factors  : A Period of Rapid Growth Military-Industrial complexMilitary-Industrial complex (before 1960) (before 1960) Space programSpace program Expand beyond military and spaceExpand beyond military and space 各類公司：製藥，電腦，汽車等 各類公司：製藥，電腦，汽車等

A History of Human Factors  : Computers, Disasters, and Litigation （訴訟） and Litigation （訴訟） Computer technologyComputer technology Technological disasterTechnological disaster  工廠  核能電廠 Litigation: expert witnessesLitigation: expert witnesses  Design: defect  Warnings and instructions: effectiveness

A History of Human Factors  1990 and Beyond Computer technologyComputer technology Human-Computer Interaction Human-Computer Interaction Aviation safety （飛航安全）Aviation safety （飛航安全） Design of medical devicesDesign of medical devices Design for the elderlyDesign for the elderly Quality of life and workQuality of life and work (end) (end)

Human Factors Profession  Academic specialty – Highest degree Tab 1-1 Tab 1-1 Tab 1-1 Tab 1-1  Principle area of work Tab 1-2 Tab 1-2 Tab 1-2 Tab 1-2  Activities performed Tab 1-3 Tab 1-3 Tab 1-3 Tab 1-3 (end) (end)

Systems  Definition  Human-Machine Systems  Characteristics of Systems  System Reliability

Systems  Definition A system is an entity A system is an entity that exists to carry out some purpose. that exists to carry out some purpose. (Bailey, 1982) (Bailey, 1982)  Human-Machine Systems Fig 1-1 Fig 1-1 Fig 1-1 Manual SystemsManual Systems Mechanical SystemsMechanical Systems Automated SystemsAutomated Systems

Systems  Characteristics of Systems Systems Are PurposiveSystems Are Purposive Systems Can Be HierarchicalSystems Can Be Hierarchical S ystem-Subsystem-Component S ystem-Subsystem-Component  Boundary of the system result in a system that performs an identifiable function result in a system that performs an identifiable function  Limit of resolution lowest limit: components lowest limit: components proper limit: why describe or analyze the situation proper limit: why describe or analyze the situation

Systems  Characteristics of Systems Systems Operate in an EnvironmentSystems Operate in an Environment  Environment: outside its boundaries  Immediate, Intermediate, General Environment  Environment impose constraints on behavior

Systems  Characteristics of Systems Components Serve FunctionsComponents Serve Functions Four basic functions: Fig 1-2 Fig 1-2 Fig 1-2  Sensing (information receiving) from outside or inside (feedback) from outside or inside (feedback)  Information storage  Information processing and decision  Action functions physical control action, communication action physical control action, communication action

Systems  Characteristics of Systems Components InteractComponents Interact work together to achieve system goals work together to achieve system goals Systems, Subsystems, and Components Have Inputs and OutputsSystems, Subsystems, and Components Have Inputs and Outputs  Closed-loop system continuous feedback & control continuous feedback & control  Open-loop system: feedback improve subsequent operation feedback improve subsequent operation

Systems  System Reliability Reliability: dependability of performance in carrying out an intended function in carrying out an intended function Probability of successful performance: discrete Mean time to failure (MTF) : continuous

Systems  System Reliability Components in Series: p 1 × p 2 × p 3 × p 4 × p 5 …Components in Series: p 1 × p 2 × p 3 × p 4 × p 5 … Components in Parallel :Components in Parallel : backup, redundancy backup, redundancy 1-(1-p) n (e.g.) 1-(1-.7) 4 = (1-p) n (e.g.) 1-(1-.7) 4 =.992 DiscussionDiscussion  Changes as a function of time: 往往每況愈下  Human (end) (end)