MG 375 Unit 3 Homework Torres

Torres 1 K. Law, Instr. MG 375 UNIT 3 HOMEWORK Chapter 6 Questions 1-6 1. What is the daily capacity of the assembly line designed by the engineers? Assume that the assembly line has a computer at every position when it is started at the beginning of the day. A. The assembly line runs for 7.5 hours a day, the longest workstation is 2 minutes, so the formula would be (7.5hrs *60*60=27000) (27000/120=225), so the daily capacity would be 225 per day. 2. When the assembly line designed by the engineers is running at maximum capacity, what is the efficiency of the line relative to its use of labor? Assume that the supporter is not included in efficiency calculations. A. Efficiency= sum of task time/workers*total time*100 (75+85+97+105+101+120=583) (7.5*60*60/1=27000/225=120*6=720) 583/720*100= 80.97% 3. How should the line be redesigned to operate at the initial 250 units per day target, assuming that no overtime will be used? What is the efficiency of your new design? A. Workstation 9 is currently 120 sec. but if tasks (16 & 17) are split, that means hiring a new worker to open workstation 10, the process cuts #9 work in half but at the same time, it does not add more time to the total production time. Efficiency to labor= sum of task time/workers*time*100=(75+85+97+105+101+60+60=583)(7.5*60*60=27000) (27000/250=108) (7*108=756) 583/756*100= 77.11% 4. What about running the line at 300 units per day? If overtime were used with the engineers’ initial design, how much time would the line need to be run each day? A. 7.5+ 2.5*60*60=36000/120=300 In order to complete 300 units 2.5 hours of overtime is needed. 5. Design a new assembly line that can produce 300 units per day without using overtime (specify the tasks at each position in the line as done in Exhibit 6.9). Workstation #1 Assemble cover (75) #2 Install LCD in cover (61) #3 Prepare base assembly (24) Install main printed circuit board (M-PCB) in base (36) #4 Install CPU (22) Install batteries and test (29) #5 Install Acupoint pointing device and wrist rest (32) Install speaker and microphone (44) #6 Install Auxiliary printed circuit board (A-PCB) (29) Prepare and install keyboard (26) #7 Prepare and install solid state drive (52)

Torres 2 Install battery (7) Install memory card (5) Start software download (11) #8 Software Loads #9 Software Loads #10 Software Loads #11 Test Video (60) #12 Test Keyboard (60) 6. What other issues might the manager consider when bringing the new assembly line up to speed? A. Equipment maintenance, communication with workers, inventory management, cost management are just a few things I could think of. Chapter 7 Students arrive at the Administrative Services Office at an average of one every 15 minutes, and their requests take, on average, 10 minutes to be processed. The service counter is staffed by only one clerk, Judy Gumshoes, who works eight hours per day. Assume Poisson arrivals and exponential service times. a. What percentage of time is Judy idle? b. ( λ ) = ¿ 1 student every 15 minutes= 4 in hour c. (µ)= average service time 10 each student= 6 in hour d. (λ / µ) 4/6= 0.667 e. Idle= 100%-66.7%= 33.3% Judy is idle 33.3% of the time. b. How much time, on average, does a student spend waiting in line? Time in wait= Wq= λ μ ( μ − λ ) 6 x ( 6 − 4 ) ¿ 4 ¿ =19.99 = 20 minutes c. How long is the (waiting) line on average? Wait in line= Lq= λ x 2 μx ( μ − λ )