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the practile journal of human factor engineering ...!!!

the practile journal of human factor engineering ...!!!
much considerable factor of human while design the system or product to do work ....!!

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  • 1. MEHRAN UNIVERSITY OF ENGINEERING & TECHNOLOGY JAMSHORO SINDH HUMAN FACTORS ENGINEERINGNAME: MOHAMMAD YOUNUSROLL NO: 08IN70
  • 2. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL JOURNAL OF HUMAN FACTORS ENGINEERING CERTIFICATEIt is to Certify that Mr. / Miss: ………………………………………………………………… bearing roll no:…………………………….. has carried out the necessary practical works as per course of studies of the subject……………………………………………………….. For the year ………………………. as shown in the practicalschedule of this journal. Professor In charge …………………. Department of ……………………….. Date ………………………………….. Head of the Department ………………Prepared by MOHAMMAD YOUNUS (08IN70) Page 2
  • 3. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT CONTENTSS.NO. OBJECT PAGE NO.01. Observe the effect of environment on the performance of human body. 0402. To observe that how the work place i.e. sitting and table height affects the 06 performance of human being.03. Effects of work load on the performance of human body. 0904. How the man-machine interaction can be enhanced while designing the product. 1205. Prove that the user performance decreases with the increasing noise. 1306. How illumination is measured and what are its methods. 1507. Suggest the best numeric keyboard and structure for calculator / telephone. 1708. Suggest the different seating arrangements for male and female students according 19 to their ages and dimensions.09. Measure the position of eye using terminals. 2310. Suggest the best arrangements of components within a physical space. 2511. Suggest the best criteria and counting the information/ speech. 27Prepared by MOHAMMAD YOUNUS (08IN70) Page 3
  • 4. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACITICAL # 1TITLE: Effects of the environment.OBJECT: Observe the effect of environment on the performance of human body.EQUIPEMENT: Room thermometer, computer, stop watch, machine lab ceiling fan, and pc lab. And differentlocations.THEORY: According to human factors engineering, it is assumed that “The environment (i.e.temperature, illumination, humidity) affect the performance of human body.”DESCRIPTION: Many occupation and task expose implies to hot or cold working environment it is importantto distinguish between a condition which threatens health and safety and a feeling of discomfort. Thermal discomfort may be experienced even there is a little likely hood of medicalcondition developing. For example, office workers may feel uncomfortable if there air conditioningis not working to optimum effect in hot weather, which could result in a real risk of heat relatedillness which may create a serious threat to health. Preventive step should aim to reduce thermaldiscomfort as much as is practicable and to develop working condition and work practices which willnot give rise to more serious problems.PROCEDURE: To prove the above statement following experiment was conducted in human factorsengineering laboratory. The main elements of experiment were :1. A group of four students was chosen per experiment.2. Every student was given the same 30 minutes to type on computer.3. Every student was provided with different environment conditions i.e. temperature.4. All students were kept in close supervision.Prepared by MOHAMMAD YOUNUS (08IN70) Page 4
  • 5. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT5. The temperatures were manipulated.OBSERVATION: Refer the table below Written Time Errors in Level of S.No Temperature Experience article given writing performance Introduction 1. 30 minutes Too high 2-yrs 200 Very poor to H.F.E 2. Same 30 minutes Too low 2-yrs 195 Poor 3. Same 30 minutes Moderate 2-yrs 180 Good Room 4. Same 30 minutes 2-yrs 150 Very good temperatureRESULTS: From the above experiment it was concluded that the human performance is affected by theenvironmental conditionsStandard temperature for the office work is suggested around 20 to 24 o C and 30 to 60 %. It doesnot mean that the work could not be done beyond this temperature range. Similarly is the case withother factors such as, illumination, noise, humidity etc. causing human performance to be decreasedair temperature can cause sweating, dizziness, muscle cramps, shivering, hypo-thermia etc. humiditycan cause discomfort, flushed skin, headache, vomiting etc.Prepared by MOHAMMAD YOUNUS (08IN70) Page 5
  • 6. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 2TITLE: Improper work place.OBJECT: To observe that how the work place i.e sitting and table height affects the performance ofhuman being.REQUIREMENTS: Computer, different chairs, different table size, PC lab, stop watch.DESCRIPTION: Different people have different physical dimension and required different sort of chairs andtable regarding comfort and ease so has to maximize the performance in the work place.PROCEDURE: To prove the above statement following experiment was conducted in human factorengineering laboratory. The main elements of experiment were:1. A group of four students was chosen per experiment.2. Every student was given the same 30 minute to type on computer.3. Every student was provided with different sizes and types of chairs and table and also tasks to work with.4. All students were kept in closed supervision.5. All students were interviewed to know their view.Prepared by MOHAMMAD YOUNUS (08IN70) Page 6
  • 7. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT Feeling fatigue and pain in legs due to hard positionOBSERVATION: Refer the table given below Type of task MALE FEMALE (seated) Inch cm inch Cm Fire work 39.0-41.5 99-105 35.0-37.5 89-95 Precision work 35.0-37.0 89-94 32.5-34.5 82-87Light assembly 29.0-31.0 74-78 27.5-29.5 70-75Coarse/medium 27.0-28.5 69-72 26.0-27.5 66-70 work Reading and 29.0-31.0 74-78 27.5-29.0 70-74 writingRange for typing 23.5-27.5 60-70 23.5-27.5 60-70 desks Computer 23.0-28.0 58-71 23.0-28.0 58-71 keyboard usePrepared by MOHAMMAD YOUNUS (08IN70) Page 7
  • 8. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENTCONCLUSION: Form the above practical we concluded that before designing any type of chair or tablefollowing point should be kept in mind.1. For whom we are designing.2. The work for what it will be used.3. The environment where it (chair/table) will be used.4. The color of the chair.5. The ratio of flexibility etc.Thus we conclude that for designing any chair or table we have to satisfy a large number of userpopulations so as to provide comfort and ease with great degree of flexibility.Prepared by MOHAMMAD YOUNUS (08IN70) Page 8
  • 9. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 3TITLE: Workload.OBJECT: Effects of work load on the performance of human body.REQUIREMENTS: Working environment and stethoscope.DESCRIPTION: There are many factors that contribute to the work load experienced by the people whileengaged in physical work. Astrand and rodahl (1986) presented the major factors that influence thebody energy level of output.The factors include: nature of work, somatic factors, training, motivation and environment.These influence the energy output level through the physiological service function of supplying fueland oxygen for muscle metabolism. Efficiency (%) = Work output x 100 Energy consumptionPROCEDURE:1. Students are made to perform different types of work such as pulling or pushing the carts etc.2. After performing the task, heart rate was calculated at worm up position.3. Energy consumption is also calculated.4. In last, conclusion was made regarding the students fitness for particular work.Prepared by MOHAMMAD YOUNUS (08IN70) Page 9
  • 10. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT Feeling fatigue and pain in limbs Feeling fatigue while doing due to heavy load work due to work loadOBERVATION: Estimated work efficiency for various activities. Activity Efficiency Shoveling (stooped posture) 3 Shoveling (normal posture) 6 Using heavy hammer 15 Going down and up stairs 23 Pulling a cart 24 Pushing a cart 27 Cycling 25Prepared by MOHAMMAD YOUNUS (08IN70) Page 10
  • 11. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENTGrade of physical work based on energy expenditure level. Oxygen Energy Energy Heart rate Grade of work consumption expenditure(kcal/min) expenditure (beats/min) (L/min) Rest (sitting) 1.5 >720 60-70 .3 Very intense 1.5-2.5 768-1200 65-75 0.3-0.5 work Light work 2.5-5.0 1200-2400 75-100 0.5-1.0Moderate work 5.0-7.5 2400-3600 100-125 1.0-1.5 Heavy work 7.5-10.0 3600-4800 125-150 1.5-2.0 Very heavy 10.0-12.5 4800-6000 150-180 2.0-2.5 work Un-duly heavy >12.5 >6000 >180 >2.5 workRESULT: Knowing the heart rates and energy consumption, performing different task, it can beconcluded that which job is suitable for the user.Prepared by MOHAMMAD YOUNUS (08IN70) Page 11
  • 12. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 4TITLE: Man-machine interaction.OBJECT: How the man-machine interaction can be enhanced while designing the product.REQUIREMENTS: Two students, two computers (one black & white and one colored), written specimen, properelimination, temperature and seating arrangement.DESCRIPTION: For the better performance of the user at work, it is important that the work area shouldpossess the quality to match man and machine and it can be improved by making the machine moreuser friendly.PROCEDURE: To prove the above statement, following experiment was conducted. The main elements offexperiment are as under.Two students were selected, provided the same illumination, temperature, working area, typingexperience and written specimen.One student was provided the colored pc while other black & white.Both were given one hour to type on their respective pc.Both students are kept in close supervision.Both were interviewed by supervisor at the end of experiment.OBSERVATION: From above experiment following results were derived.1. Student with colored pc wrote more words than that of having black & white pc.2. Student having colored pc had better visualization.3. Colored pc student had less eye and mental fatigue.4. Student with colored pc was more will to do work.Prepared by MOHAMMAD YOUNUS (08IN70) Page 12
  • 13. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 5TITLE: Noise.OBJECT: Prove that the user performance decreases with the increasing noise.REQUIREMENT: Lathe machine, sharper machine, drill machine, grinding machine, students and workspecimen.DESCRIPTION: Noise is such type of sound which creates irritation and can result performance reduction.PROCEDURE: Following procedure was adopted to prove the above statement.1. All mentioned machines were operated and caused noise at the level of 9000 Hz.2. Students were assigned to work on lathe, shaper, drill and grinding at same time.3. After 15 minute, the performance was checked and evaluated.4. Now lathe machine was stopped while the other machines were let to work with the reduced level of noise to 8000 Hz.5. After another 15 minutes, the performance was checked and evaluated.6. This time sharper and drill machines were stopped while grinding machine was continued to work with the reduced level of noise to 6500 Hz.7. In same way, the performance of students was checked.OBSERVATION:1. The operation must be given protective devices while working in noisy environment.2. There must be provision of ventilation in workplace so that most of the noise can be absorbed.Prepared by MOHAMMAD YOUNUS (08IN70) Page 13
  • 14. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT3. The base of the machine should produce less vibration.4. The work area and building must be designed in a way that there is no echo in building.5. Proper maintenance of machine can also result in noise reduction. Feeling irritation while doing work due noisy environmentRESULT:1. As the machine operation was stopped, the noise was reduced and lead to the better performance.2. The finished product came up with better quality.3. The decreasing noise also enhanced the degree of better communication among the students.4. The students were feeling less fatigue as the machines were stopped one by one.5. The decreased noise can result in better quality and performance of the students.Prepared by MOHAMMAD YOUNUS (08IN70) Page 14
  • 15. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 6TITLE: Illumination.OBJECT: How illumination is measured and what are its methods.REQUIREMENTS: LUX meter, artificial light (candle), measurement tape, paper and pencil.DESCRIPTION: Illumination includes both artificial light source such as lamps and natural illumination ofinteriors from daylight. Illumination represents a major component of energy consumption,accounting for a significant part of all energy consumed worldwide.Artificial illumination is provided today by electric lights, but previously by gas lighting candles oroil lumps. Proper lighting can enhance task performance or aesthetics; while there can be energywastage and adverse health effects of lighting. It is valuable to provide the correct light intensity and color spectrum for each task orenvironment. Otherwise, energy not only could be wasted but over-illumination can lead to adversehealth and psychological effects. Specification of illumination requirements is the basic concept of deciding how muchillumination is required for a given task.PROCEDURE: Following is the procedure for conducting this practical by putting LUX meter in vertical andhorizontal position.1. First we check the room/lab illumination , i.e 50 lux2. Mark the starting and ending point from 0 to 12 inches respectively.3. We place the candle at 12 inches away from the lux meter.Prepared by MOHAMMAD YOUNUS (08IN70) Page 15
  • 16. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT4. After that we remove the lux meter towards the candle with equal distance of 1 inch and record the reading.READING: Reading available in the room/lab in vertical = 150 In horizontal = 175 Candle height = 4” Lame = 2”Position of LUX meter CandleHorizontal Vertical200 300 12250 150 11200 250 10300 300 09325 250 08300 350 07350 375 06400 450 05450 800 04550 700 03350 1000 02400 1700 01RESULT: From the above recorded data, we conclude that the distance that the distance from sourcedecreases the illumination.Prepared by MOHAMMAD YOUNUS (08IN70) Page 16
  • 17. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 7TITLE: Best numeric keyboard.OBJECT: Suggest the best numeric keyboard and structure for calculator / telephone.INSTRUMENTS: Telephone set (digital), calculator, stopwatch, pencil and paper.PROCEDURE: To suggest the best arrangement of keys on both telephone and calculator, first we have toexamine the existing structure of both. % OFF ON CHECK % OFF ONR-ME M+ M- / R-ME M+ M- / 7 8 9 X 7 8 9 . 4 5 6 - 4 5 6 * 1 2 3 - 1 2 3 + 0 . = ANS CALCULATOR CALCULATOR (Standard Model) (Suggested Model)Prepared by MOHAMMAD YOUNUS (08IN70) Page 17
  • 18. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT 1 2 3 # 0 * 4 5 6 3 6 9 7 8 9 2 5 8 * 0 # 1 4 7 TELEPHONE TELEPHONE (Standard model) (Suggested model)S. No Model type Number dialed Duration (seconds)1 Standard 0313-3167888 5.001 Suggested 0313-3167888 6.752 Standard 0313-3167888 4.52 Suggested 0313-3167888 7.00Prepared by MOHAMMAD YOUNUS (08IN70) Page 18
  • 19. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 8TITLE: Seating arrangement.OBJECT: Suggest the different seating arrangements for male and female students according to theirages and dimensions.REQUIREMENT: Measuring tape, vernier caliper, scale, paper and pencil.DESCRIPTION: Diverse evidence from many cultures shows that sitting has been associated with numerousproblems: back pain of all sorts, fatigue, varicose veins, stress and problems with the diaphragm,circulation, digestion, elimination, and general body development.PURPOSE: According to Cranz and other radical ‘somatic’ practitioners who practice ‘new ergonomics’is that we have been forced into a ‘table’ and ‘chair’ culture. Where many activities take place in aright-angled seated position. This position forces the body into a C-shaped slump and this placesuneven pressure on the vertebral disks of the lower back. With time, the spine can become deformedand erode disks. Adjusting the fit, title, and height of your chair is very important for proper posture andcomfort. The backrest of the chair should have a snug fit against your back. Every chair is different,but in general, looks for height, lumbar support, and tilt adjustments. If you find that you needadditional lumber support, a back cushion can be used to customize your chair. Adjust your seat tiltso you are sitting up right with your feet firmly on a surface and your lower back well supported. Setchair height so that your hands and wrists should remain at the same level as the home row on thekeyboard. If these adjustments cause your feet to dangle, you’ll need a foot rest.PROCEDURE:Prepared by MOHAMMAD YOUNUS (08IN70) Page 19
  • 20. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT Firstly, we choose a student of height 5.8 feet among all the students. We started takingmeasurement.1. Inner side of the foot = 9.5”2. Foot to knee = 18.5”3. Thigh to lumber lord sis = 23.0”4. Waist = 33.05. Lumber lord sis shoulder = 27.0”6. Shoulder to head = 13.5” After taking all the measurements, we suggested the following dimensions of the computerchair for the students. The dimensions are:1. Height of the seat = 17.0”2. Thickness of the seat = 2.0”3. Width of the seat pan = 17.5”4. Height of the back rest = 18.0”5. Width of the back rest = 17.0”6. Angle of the back rest = 1000 - 1100 “I love my ergonomic office chair. It reclines, has heated vibrating massage, and provides electro-shock therapy at the end of a stressful”.Prepared by MOHAMMAD YOUNUS (08IN70) Page 20
  • 21. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENTRESULT:1. Students were feeling more comfortable.2. They were not feeling back ache after sitting for more than an hour.3. The recommended height of the chair improved the typing performance because the suggested dimensions gave proper compatibility of arms and keyboard.4. Due to proper height of the chair, the leg swelling was reduced up to 50%.STANDARD ADJUSTMENT TO BE MADE: Start our adjusting a chair from the ground up. Start with the height and move up from there.While adjusting the chair, worry first about getting the chair adjusted to fit you. Afterwards, look atthings like the height of the desk, keyboard etc. Too often, people adjust a chair too high so they canreach the keyboard rather than properly adjusting the chair and adding a keyboard tray to move thekeyboard to the correct height.SEAT HEIGHT: Start by adjusting the height until your things are parallel to the floor, stand in front of thechair and adjust the height until the top of the seat pan is at the height of the bottom of your kneecap.Then, sit in the chair and make small height adjustments until your things are parallel to the ground.Sit in this position for a while before making any further changes in seat height. When you havePrepared by MOHAMMAD YOUNUS (08IN70) Page 21
  • 22. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENTbecome accustomed to this height, adjust the chair height up/down 1-3 inches until you find alocation that is comfortable for you while seated (don’t worry about that keyboard height yet!).SEAT DEPTH: Adjust the seat pan until you have about three fingers to a fist’s width of room between theback of your calf and the front edge of the chair when your back is touching the backrest. If the seatpan is not adjustable and the pan is too deep, add padding to the backrest (a towel over the backrestof the chair or a backrest cushion) to shift you forward in the seat while maintaining contact with thebackrest. If the seat pan is too shallow, start looking for a new chair.SEAT ANGLE: There are three basic postures. The standard posture calls for a level seat pan so it is notnecessary to adjust the tilt for this posture. Likewise, the reclined posture can have the seat flat aswell. However, some people prefer to have a very slight backward tilt on the seat pan to help keepthem in the seat. In the forward tilt posture, the seat pan is tilted forward 5-100. start by raising theoverall height of the chair a few inches, and then tilt the seat pan forward.Prepared by MOHAMMAD YOUNUS (08IN70) Page 22
  • 23. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 9TITLE: Vision and eye.OBJECT: Measure the position of eye using terminals.THEORY: The eye is a fluid membranous sphere which converts the electromagnetic radiations intonerve impulses. It is very sensitive organ of human body. It consists of nine parts working differentlyfrom each other.1. Cornea.2. Pupil.3. Lens.4. Iris.5. Suspensor ligaments.6. Retine.7. Foveae.8. Blind spot.9. Optic nerve.PROCEDURE: Light enters the eye through a transparent outer covering called the cornea. The cornea playsvery important role in reflecting the incident light. Further reflection occurs as the light passesthrough the lenses. During the working on the places where terminals are use then person always tryto sit at keep distance because when we use the rules then we do not feel fatigue earlier. The standarddistance of terminal from human eye is 20-25 inches and the position of the eye is 7-10 inches fromcenter. These are the standard and by using these rules we reduce the human eye fatigue.Prepared by MOHAMMAD YOUNUS (08IN70) Page 23
  • 24. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENTOBSERVATION:Distance from eye to Height of terminal Height of eye from Illuminationterminal (inches) from center (inches) sitting posture (inches)15-20 2-5 20 Normal20-25 7-10 24 Standard30-35 10-13 28 LowPrepared by MOHAMMAD YOUNUS (08IN70) Page 24
  • 25. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 10OBJECT: Suggest the best arrangements of components within a physical space.REQUIREMENTS: Stop watch, set of different components and drill machine.THEORY: Working safety begins with looking at the physical arrangements of your work space anddesign of the tools you use. This draws from the science of ergonomics which strives to fit the workto the body rather than forcing the body to conform the work. As logical as this may sound, it isactually a pretty view. Ergonomics is being abused as marketing term, being thrown as easily as the word “natural”is with food. Suddenly every thing is “ergonomically designed”. A product will not be veryergonomic for someone if it is not used in the right way for the right purpose. And since manyergonomic products are adjustable, it takes training to take advantage of what they have to offer.Otherwise they can be just as uncomfortable or injurious as your old furniture. One of the most common scenario seen today is the company which buy new furniture with awide range of adjustability but does not teach its employees how they operate or in what principles toadjust them. There are examples of companies where cumulative trauma problems increased afterinstalling ergonomics furniture. Imagine their surprise! The answer is training. You need to understand the principle behind ergonomics design. It is really very simple. Thegoal is to prevent unnecessary muscular efforts, and avoid postures which put strain on the body. Inshort, to make you comfortable.Prepared by MOHAMMAD YOUNUS (08IN70) Page 25
  • 26. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT Maximum and minimum reach at work stationPROCEDURE: For the drilling purpose, the major components required are1. Drill bits2. Cutting oil3. Job The drill bits should be placed alongside the machine so that they can easily be reached. The cutting oil is required during the drilling process and should be provided with in the formof pipe pouring the oil continuously on the job. The height of the machine should be suitable and proportionate to the size of the workerbecause it is too high, the worker can not reach it and if it is too low, the worker will have to bend,including a lot of fatigue.Prepared by MOHAMMAD YOUNUS (08IN70) Page 26
  • 27. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT PRACTICAL # 11OBJECT: Suggest the best criteria and counting the information/ speech.THEORY: In the process of designing the speech communication system, one needs to establish thecriteria or standards the system should need to be acceptable for the interred uses. Criteria are alsorequired to evaluate the effects of noise and ear protectors on speech communication and to measurethe effectiveness of hearing aids. The major criterion for evaluating a speech communication systemis intelligibility, but there are others as well, including quality or nature less of the speech.SPEECH INTELLIGIBILITY: Intelligibility is simply the degree to which a speech message (e.g. a list of words) iscorrectly recognized. Intelligibility is assessed may transmitting speech material to individuals whoare asked to repeat what they hair or to answer question about what they hair. Various speechintelligibility tests exists which differ in terms of types and materials presented “ example : nonsensesyllables politically balanced (PB) words list that contain all the various speech, sounds andsentences “ In general, in a given situation, intangibility is highest for sentences, lessees for isolatedwords and lowest for nonsense syllables.SPEECH QUALITY: Speech quality or naturalness goes beyond intangibility. It is important in situation where it isdesirable to recognize the identity of speaker such as on the telephone. Speech quality is alsoImportant as one determinate of user satisfaction with a communication system, for example: mobiletelephone for auto mobiles have become relatively in expensive and available. In telephones, for thehome that allow a person to talk and hear from any where in the room “Called speaker phone” arealso popular, automatic telephone, answering machine are also be coming common in all these cases.The quality of speech heard over the system often the critical factor that accounts for the purchase ofone system over another.Prepared by MOHAMMAD YOUNUS (08IN70) Page 27
  • 28. DEPARTMENT OF INDUSTRIAL ENGINEERING AND MANAGEMENT Speech quality is defined in terms of preferences usually samples of speech are presentedover the system and people are asked to either rate the quality (excellent, fair, poor, un-expectable).This type of methodology is often used to evaluate synthetic speech as well.Prepared by MOHAMMAD YOUNUS (08IN70) Page 28