15-第十五章 短期调度.doc

Short-Term Scheduling第十五章 短期调度主要内容Outline15.1 短期调度的战略重要性[The Strategic Importance of Short-Term Scheduling] [高效+高速+低库存+准确的交货期] 15.2 调度问题[Scheduling Issues] [能力计划+综合计划+主生产计划+短期调度]正向与逆向调度[定制]Forward and Backward Scheduling调度准则Scheduling Criteria[时间短+利用率高+库存少+等待短]15.3 工艺专业化设施的调度[Scheduling Process-Focused Facilities] [计划文件] 15.4 作业分配[Loading Jobs] 输入---输出控制Input-Output Control[固定在制品卡片] 甘特图Gantt Charts 分配方法Assignment Method [指派问题-匈牙利法] 15.5 作业排序[Sequencing Jobs] 派工的优先规则Priority Rules for Dispatching Jobs[FCFS+SPT+EDD+LPT] 关键比Critical Ratio[剩余交付时间/剩余作业时间] N项作业两台机器的排序问题：约翰逊规则Sequencing N Jobs on Two Machines: Johnson’s Rule 基于规则的作业派工系统的局限性Limitations of Rule-Based Dispatching Systems 15.6 有限能力计划[Finite Capacity Scheduling (FCS)] 15.7 约束理论[Theory of Constraints] 瓶颈Bottlenecks 鼓、缓冲、绳子Drum, Buffer, Rope[节拍+库存+信号] I5.8 重复性设施的调度[Scheduling Repetitive Facilities] [物料平准化] 15.9 服务业的调度[Scheduling Services] [24/7运作+需求管理+能力管理] 用循环调度法编制服务人员的工作班次Scheduling Service Employees with Cyclical Scheduling[循环调度] [案例] 达美航空：天气不佳时的飞行调度Global Company Profile: Delta Air Lines达美航空公司每年有近10%的航班受到各种影响，其中一半是由于天气原因引起About 10% of Delta’s flights are disrupted per year, half because of weather公司每年损失4.4亿美元，包括收入损失、加班工资以及乘客的食宿费用Cost is $440 million in lost revenue, overtime pay, food and lodging vouchers公司投入3千3百万建立运营控制中心以适应各种变化[通讯+除冰+及时通知乘客+变更航线]和保持航班准确运行The $33 million Operations Control Center adjusts to changes and keeps flights flowing每年节约3千五百万Saves Delta $35 million per year15.1 短期调度的战略重要性[The Strategic Importance of Short-Term Scheduling综合计划的落实] 有效和高效的调度是企业的一个竞争优势Effective and efficient scheduling can be a competitive advantage高效的调度意味着商品或者服务更快的通过生产设施，提高了资产的利用率，从而降低了成本Faster movement of goods through a facility means better use of assets and lower costs高效的调度意味更强的生产能力，更快的吞吐速度以及生产柔性，意味着更快的交货速度从而可以为顾客提供更好的服务Additional capacity resulting from faster throughput improves customer service through faster delivery良好的调度意味着更可靠的交货期Good schedules result in more dependable deliveries15.2 调度问题[Scheduling Issues]-领导-指挥-战争战役指挥员[给我冲+跟我冲]调度就是安排各项运作的时间Scheduling deals with the timing of operations调度的任务就是根据设备能力对需求[预测+订单]进行分配并安排优先级The task is the allocation and prioritization of demand调度要考虑的问题Significant issues are调度的类型，正向还是逆向的The type of scheduling, forward or backward[迎战+进攻]调度准则的优先标准 The criteria for priorities不同组织调度决策有不同内容[Scheduling Decisions] [医院、学校、制造商、餐厅及航空公司]组织Organization管理人员需要对以下内容进行调度Managers Must Schedule the Following医院Arnold Palmer Hospital手术室的使用Operating room use病人收治Patient admissions护理人员、安全人员以及设备护理人员Nursing, security, maintenance staffs门诊患者的治疗Outpatient treatments大学University of Missouri教室和音响设备Classrooms and audiovisual equipment学生和教师的课表Student and instructor schedules本科生和研究生的课程Graduate and undergraduate courses工厂Lockheed Martin factory产品生产Production of goods物料采购Purchases of materials工人Workers餐厅Hard Rock Cafe厨师、服务员、吧台侍者Chef, waiters, bartenders新食物交付Delivery of fresh foods表演人员 Entertainers餐厅营业时间Opening of dining areas航空公司Delta Air Lines飞机维护Maintenance of aircraft起飞时间表Departure timetables航班机组人员、餐饮服务人员、登机口和检票人员Flight crews, catering, gate, ticketing personnel调度工作计划流程Scheduling Flow [把握组织的能力计划+综合计划+主生产计划+短期调度的关系]能力计划[长期，年] 设备变更设备调整综合计划[中期，季度或月]设备利用率人员调整分包主生产计划[中期，周]物料需求计划分解综合生产计划短期调度[短期，天、小时或分钟]工作中心负荷作业排序/分派15.2.1正向调度与逆向调度[Forward and Backward Scheduling]正向调度Forward scheduling正向调度一旦需求已知，就开始调度Forward scheduling starts as soon as the requirements are known产生一个可行的时间表，虽然它可能无法满足交货期Produces a feasible schedule though it may not meet due dates经常导致在制品库存积压Frequently results in buildup of work-in-process inventoryDue DateNow[案例] 医院、诊所、餐厅和机床制造等[一般上班前准备好]。

逆向调度Backward scheduling逆向调度从计划交付期开始，首先从最后一项作业开始调度Backward scheduling begins with the due date and schedules the final operation first对其他工序逆向依次进行调度Schedule is produced by working backwards though the processes实现调度计划所需资源可能出现匮乏Resources may not be available to accomplish the scheduleDue DateNow[案例]制造业企业+宴会+安排手术[有需求就准备]有时两者结合效果更好[Often these approaches are combined to develop a trade-off between a feasible schedule and customer due dates]15.2.2调度准则[Scheduling Criteria]调度在于优化资源满足生产目标Optimize the use of resources so that production objectives are met完成时间最短[Minimize completion time]利用率最高[Maximize utilization of facilities]在制品库存最少[Minimize work-in-process (WIP) inventory]顾客等待时间最短[Minimize customer waiting time]不同工艺流程的调度方法Different Processes/ Different Approaches：工艺专业化设施[作业车间]+工作单元+重复性生产设施[装配线]+连续性生产+大规模定制工艺专业化设施Process-focused facilities正向调度Forward-looking schedules MRP due datesFinite capacity scheduling工作单元Work cells正向调度Forward-looking schedulesMRP due datesDetailed schedule done using work cell priority rules重复性生产设施Repetitive facilities正向调度Forward-looking schedule with a balanced linePull techniques for scheduling连续性生产Product-focused facilities正向调度Forward-look。