【正文】 下表所示 100 75 50 25 臺時定額（臺時 /件） 100 120 200 280 計劃產量（件） D C B A 產品名稱 項目 生產與運作管理 Nr. 14 720 合計 103 200 2 100 100 D 124 180 75 120 C 207 200 1 50 200 B 289 744 140 25 280 A ⑦ ⑥ ⑤ =② 4 ④ ③ ② ① 換算為具體產品表示的能力 以代表 產品表 示的能 力 換算為 代表產 品的產 量 換算系數 臺時定額 計劃產量 項目 產品名稱 實際能生產的數量 生產與運作管理 Nr. 15 綜合計劃 (Aggregate Planning)策略 ? Aggregate planning (AP): macro planning, addresses problem of deciding how many employees the firm should retain and, for a manufacturing firm, the quantity and the mix of products to be produced ? The aggregate planning methodology: demand is deterministic or known in advance. ? Aggregate planning methodology: translate demand forecast into blueprint for planning staffing and production level for a firm over a predetermined planning horizon ? Aggregate planning (AP) involves peting objectives. – Make frequent and large changes in size of labor forcea chase strategy to react quickly to anticipated changes in demandcost effective, but a poor longterm strategy – Retain a stable workforceresults in larger buildups of inventory during period of low demand – Develop a production plan for a firm to maximize profit over the planning horizon subject to constraints on capacity 生產與運作管理 Nr. 16 生產大綱的制定 ? 生產大綱的制定程序 Y 已得到的訂單 期望的庫存 預測的需求 確定每段時間 的需求 確定每段時間 的能力 確定企業(yè)有關 政策 確定各種單位 費用 提出備選計劃 計算費用 確定生產大綱 滿意否？ N 生產與運作管理 Nr. 17 ? 正規(guī)的數學方法 – 如線性規(guī)劃法 – 線性決策法則 (Linear Decision Rule)等 ? 非正規(guī)的方法 – 反復試驗法 (The TrialandError Method) 制定生產大綱的方法 生產與運作管理 Nr. 18 AP Aggregate Units of Production AP describes aggregate units in the following situations: ?In terms of ―average’ itemwhen the items produced are similar。 ?In terms of weights (tons of steel), volume (gallons of gasoline), amount of work required (workeryears of programming time, and dollar value (value of inventory in dollars)when many kinds of items are produced。 Appropriate aggregating schema are determined by context of the particular planning problem and the level of the aggregation require. 生產與運作管理 Nr. 19 AP Aggregate Units of Production Example : Decide on aggregating schema for the manager of a plant that produces six models of washing machines to determine the workforce and production levels. M ode l N u m be rN u m be r of W or ke r H ou r s R e qu i r e d t oP r odu c eS e l l i n g P ri c eS a l e sRa t e (% )A 5532 285 32K 4242 345 21L 9898 395 17L 3800 425 14M 2624 525 10M 3880 725 6生產與運作管理 Nr. 20 AP Aggregate Units of Production ?One possibility is to define aggregate unit as one dollar of outputUnfortunately, it is impossible since the selling prices of the various models are not consistent with the number of workerhours required to produce them. ?Since the percentages of the total number of sales for these six models have been fairly constant (32% ,21%, 17%, 14%, 10% and 6% for six models respectively), he decide to define the aggregate unit of production as a fictitious washing machine requiring .32?+.21 ?+.17 ?+.14 ?+.10 ?+.06 ?= hrs of labor time. M ode l N u m be rN u m be r of W or ke r H ou r s R e qu i r e d t oP r odu c eS e l l i n g P r i c eS a l e s R a t e ( % )A 5532 285 32K 4242 345 21L 9898 395 17L 3800 425 14M 2624 525 10M 3880 725 6WR/$ WR/$ 生產與運作管理 Nr. 21 從生產大綱到產品出產計劃 生產大綱或綜合計劃不涉及具體產品，不能直接用于指揮生產活動。必須將假定產品或代表產品轉換成具體產品，將綜合計劃變成產品交付計劃和產品出產計劃。 產品交付計劃規(guī)定了要向顧客交付的產品的具體型號規(guī)格和交付時間，產出產計劃規(guī)定了要出產的產品的具體型號、規(guī)格和出產時間。產品出產計劃是物料需求計劃 (Material Requirements Planning， MRP)的主要輸入。 通過 MRP處理，對具體產品的需求就會變成對構成產品的零部件和原材料的需求，使計劃得以執(zhí)行。 通過下例說明如何將綜合計劃變成產品交付計劃。 生產與運作管理 Nr. 22 例 經過反復試驗法，得出某電視機廠一季度要提供的彩電的數量，如表 78所示。綜合計劃以假定產品為單位： 1月份提供 200臺， 2月份提供 300臺， 3月份提供 400臺；將其變成具體產品，就構成產品交付計劃。具體產品合計數等于假定產品數。 在每個月，將交付數量減去相應月份的成品庫存加上相應月份顧客需要提走的數量，便可計算出每個月需要產出的數量，由此就生成了產品出產計劃。 表 7 8 綜合計劃和產品交付計劃 1 月 2 月 3 月 彩電 ( 假定產品 ) 200 300 400 具體產品： 21 英寸彩電 25 英寸彩電 29 英寸彩電 100 75 25 100 150 50 1 00 200 100 合計 200