财务管理与财务分析运营管理.ppt

财务管理与财务分析运营管理课件,2,I,Inventory Systems for Independent Demand,?,Basic fixed order quantity system,Constant Demand,Uncertain demand,?,Basic fixed time period system,?,Newsvendor model,?,Supply chain contract,OPERATIONS MANAGEMENT CLASS,3,I,4,Purposes of Inventory,1.To maintain independence of operations,2.To meet variation in product demand,3.To allow flexibility in production scheduling,4.To provide a safeguard for variation in raw,material delivery time,5.To take advantage of economic purchase-order,size,4,I,5,I,6,I,Inventory Costs,?,Holding(or carrying)costs,?,Setup(or production change)costs,?,Ordering costs,?,Shortage costs,.,7,I,Classifying Independent Demand Systems,?,Fixed-Order Quantity,The reorder point,?,Fixed-Time Period,?,Hybrid Systems-Both Together-Order,Periodically unless we reach the reorder point.,8,I,Inventory Systems for Independent Demand,?,Basic fixed order quantity system,Constant Demand,Uncertain demand,?,Basic fixed time period system,?,Newsvendor model,?,Supply chain contract,OPERATIONS MANAGEMENT CLASS,9,I,Fixed-Order Quantity Models,Economic Order Quantity(EOQ):,Assumptions,?,Demand for the product is constant and uniform,throughout the period,?,Lead time(delivery time of the order)is constant,?,Price per unit of product is constant,.,10,I,Fixed-Order Quantity Models,Economic Order Quantity:,Assumptions(contd),?,Inventory holding cost is based on average,inventory.,?,Ordering or setup costs are constant.,?,All demands for the product will be satisfied(No,lost sales are allowed),.,11,I,EOQ:A SIMPLE MODEL,?,Book Store Mug Sales,Demand is constant,at 20 units a week,Fixed order cost of$12,no lead time,Holding cost of 25%of inventory value,annually,Mugs cost$1.00,sell for$5.00,?,Question,How many,when to order,12,I,EOQ Model-Basic Fixed-Order,Quantity Model,R=Reorder point=L*d,Q=Economic order quantity,L=Lead time,d=Demand per Unit of Time,L,L,Q,Q,Q,R,Time,Number,of units,on hand,.,13,I,Cost Minimization Goal,Annual Ordering Costs,Holding,Costs,Q,OPT,Order Quantity(Q),C,O,S,T,Annual Cost of,Items(DC),Total Cost,.,TAHC=H*(Q/2),TAOC=S*D/Q,TAC=TAHC+TAOC,S:cost of placing an order or setup cost,14,I,Basic Fixed-Order Quantity Model,T,C,=,D,C,+,D,Q,S,+,Q,2,H,Total Annual Cost=,Annual,Purchase,Cost,Total Annual,Ordering,Cost,Total Annual,Holding,Cost,+,+,TC,Total annual cost,D,Demand,C,Cost per unit,Q,Order quantity,S,Cost of placing an order,or setup cost,R,Reorder point,L,Lead time,H,Annual holding and storage cost,per unit of inventory,.,15,I,Deriving the EOQ-Calculus Method,?,Using calculus,we take the derivative of the total,cost function and set the derivative(slope)equal,to zero,.,Q,=,2,D,S,H,=,2,(,A,n,n,u,a,l,D,e,m,a,n,d,),(,O,r,d,e,r,o,r,S,e,t,u,p,C,o,s,t,),A,n,n,u,a,l,H,o,l,d,i,n,g,C,o,s,t,O,P,T,R,e,o,r,d,e,r,p,o,i,n,t,R,=,d,L,_,d,=,a,v,e,r,a,g,e,d,a,i,l,y,d,e,m,a,n,d,(,c,o,n,s,t,a,n,t,),L,=,L,e,a,d,t,i,m,e,(,c,o,n,s,t,a,n,t,),_,16,I,?,Recognizing TAHC=TAOC at Optimal,?,TAHC=H*Q/2,TAOC=S*D/Q,?,H*Q/2=S*D/Q,Solving for Q Yields:,Q,=,2,D,S,H,=,2,(,A,n,n,u,a,l,D,e,m,a,n,d,),(,O,r,d,e,r,o,r,S,e,t,u,p,C,o,s,t,),A,n,n,u,a,l,H,o,l,d,i,n,g,C,o,s,t,O,P,T,R,e,o,r,d,e,r,p,o,i,n,t,R,=,d,L,_,d,=,a,v,e,r,a,g,e,d,a,i,l,y,d,e,m,a,n,d,(,c,o,n,s,t,a,n,t,),L,=,L,e,a,d,t,i,m,e,(,c,o,n,s,t,a,n,t,),_,Deriving the EOQ-Graphical Method,17,I,EOQ:OPTIMAL ORDER QUANTITY,?,Optimal Quantity=,?,So for our problem,the optimal quantity is 316,(2*Demand*Setup Cost)/holding cost,18,I,EOQ Example,Annual Demand=1,000 units,Days per year considered in average daily demand=365,Cost to place an order=$10,Holding cost per unit per year=$2.50,Lead time=7 days,Cost per unit=$15,Determine the economic order quantity and the reorder point.,.,19,I,Solution,d,=,1,0,0,0,u,n,i,t,s,/,y,e,a,r,3,6,5,d,a,y,s,/,y,e,a,r,=,2,.,7,4,u,n,i,t,s,/,d,a,y,Q,=,2,D,S,H,=,2,(,1,0,0,0,),(,1,0,),2,.,5,0,=,8,9,.,4,4,3,u,n,i,t,s,o,r,O,P,T,9,0,u,n,i,t,s,R,e,o,r,d,e,r,p,o,i,n,t,R,=,d,L,=,2,.,7,4,u,n,i,t,s,/d,a,y,(,7,d,a,y,s,),=,1,9,.,1,8,o,r,_,2,0,u,n,i,t,s,Why do we round up?,.,20,I,In-Class Exercise,Annual Demand=10,000 units,Days per year considered in average daily demand=365,Cost to place an order=$10,Holding cost per unit per year=10%of cost per unit,Lead time=10 days,Cost per unit=$15,Determine the economic order quantity and the reorder point.,Note:(Tag hidden-slide icon to project solution),.,22,I,Inventory Systems for Independent Demand,?,The definition and purpose of inventory,?,Inventory costs,?,Basic fixed order quantity system,Constant Demand,Uncertain demand,?,Customer Service-Achieving Percent Fill Rates,?,Basic fixed time period system,?,Newsvendor model,OPERATIONS MANAGEMENT CLASS,23,I,Achieving High Customer Service,?,Add buffer stock,?,Order earlier,?,Achieve desired customer service,?,Percent fill rate=.99=9,900/10,000 are supplied,directly from stock,Fixed Order Quantity,System,Under Uncertainty,24,I,Adding Safety Stock to Order Earlier,?,Fixed Order Quantity System Under Uncertainty,R=Reorder point,Q=Economic order quantity,L=Lead time,?,L,=Standard Error of Estimate During Leadtime,B=Buffer stock set to achieve P,L,L,Q,Q,Q,R=dL+B=dL+Z,?,L,Time,B,=,Add buffer stock in case demand during leadtime expected d*L,25,I,STRATEGIC IMPORTANCE OF%FILL(P),?,P is set by top management,?,P is strategic performance measure,?,P=99.8 is becoming more common,?,How do we control inventories to achieve P?,26,I,THE V,ARIANCE LAW,If X and Y are two independent random variables,and Z=X+Y then E(Z)=E(X)+E(Y),and,?,Z,2,=,?,X,2,+,?,Y,2,What if Z=X-Y?,.,27,I,Forecasting demand during,lead time,?,MEAN DEMAND=d*L,?,Where L is length of lead time,?,Assume L=3,?,d,=standard deviation in forecasting of,demand,?,?,L,=standard deviation during leadtime,.,?,?,L,=,?,d,?,This Assumes Demand is Normally Independently,Distributed,?,This Allows the Use of the E(Z)Concept,L,28,I,STATISTICAL INVENTORY CONTROL,SCIENTIFIC INVENTORY CONTROL,?,Set the reorder point to yield desired percent fill(P),?,R=dL+Z,?,L,=Mean+Buffer Stock where,?,R=Reorder Point,?,dL=Mean Demand During Leadtime,?,?,L,=Standard Error of Forecast During LT,?,Z=Value Determined to Achieve P,29,I,?,(1-P)D=Number of Units Short Per Year,?,E(Z)=Units short each order cycle when,?,L,is,1.,?,Number of Units Short Per Year=E(Z)*,?,L,*D/Q,?,Equating Both,?,E(Z)*,?,L,*D/Q=(1-P)D rearranging:,?,E(Z)=(1-P)Q/,?,L,Determining the Value of Z:,Service level E(Z)Z,30,I,Inventory Systems for Independent Demand,?,The definition and purpose of inventory,?,Inventory costs,?,Basic fixed order quantity system,Constant Demand,Uncertain demand,?,Customer Service-Achieving Percent Fill Rates,?,Basic fixed time period system,?,Newsvendor model,OPERATIONS MANAGEMENT CLASS,31,I,Inventory Management Using Marginal,?,One-Period Model,?,Classically Called the,Newsvendor Problem,?,Items Ordered Only,?,Too many,then only salvage value,?,Too little,lost customers,32,I,Newsvendor:Exercise,?,An equipment repair firm wishes to order enough,spare parts to keep machines running throughout,a trade show.,?,The repairman sell the parts at$95 each if needed,for a repair.,?,He pays$70 for the cost of each part.,?,If all the parts are not needed,they may be,returned to the supplier for a credit of$50 each.,?,The demand for the parts is estimated.,33,I,Newsvendor:Exercise,Number of,Frequency,parts,of Need,0,0.10,1,0.15,2,0.20,3,0.30,4,0.20,5,0.05,34,I,Newsvendor:Exercise,Number of,Frequency,parts,of Need,CPn,0,0.10,0.10,1,0.15,0.25,2,0.20,0.45,3,0.30,0.75,4,0.20,0.95,5,0.05,1.00,REV-COST/(REV-SLV)=0.555,Optimum order quantity is 3,35,I,Marginal profit(MP)=marginal loss(ML),?,Stove until MP(IF SOLD)=ML(IF NOT),?,Under conditions of uncertainty E(MP)=E(ML),?,P1(MP)=P2(ML)where P1 Prob of Selling and,P2 is Prob of Not Selling,?,Now P2=1-P1,?,P1(MP)=(1-P1)ML,yields:,?,P1=ML/(MP+ML),that is,stock items until the,probability of selling the last item equals P1.,36,I,NEWSVENDOR PROBLEM IS COMMON,?,NEWSPAPERS,?,GREETING CARDS,?,CALENDARS,?,TAX GUIDES,?,OVERBOOKING AIRLINE SEATS,?,OTHER APPLICATIONS?,37,I,Revenue Sharing Contract:,Blockbuster case,Before:Wholesale price of a type is$60,renting,price is$3,After:Wholesale price of a type is$9,renting price,is still$3,but the retailer needs to share 50%,revenue with the supplier,