Scheduling affects everything in an operation, but usually gets the lowest share of technical resources.

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Scheduling Systems

Scheduling affects everything in an operation, but usually gets

the lowest share of technical resources.

By Lisa Cross Senior Editor 4/2006

The new breed of automated scheduling systems allows managers to oversee print production based on real-time plant data.

Shorter cycle times and downward pressure on prices—the reality under which most print firms operate—place increasing emphasis on optimizing use of assets and resources. Automated

scheduling systems offer a tool with powerful potential to maximize both throughput efficiency and resource allocation.

Scheduling affects everything in an operation, from supplies to customer service to resource allocation. But in many companies, scheduling receives the least technical resources. Most firms still execute scheduling through a combination of magnetic chips on planning boards and static spreadsheet programs. But the components are now available, say experts and users, for widespread automation of scheduling, using applications that will allow for managing production based on real-time data collected by ERP/print management systems.

But before investing in any system, suggests Kevin Cooper, a professor at Cal. Poly State U., printers should ask themselves a few questions, such as:

Am I losing work by not having this? Will I gain work by getting this?

Will I add or lose administrative staff with this system? Will jobs get through the plant faster with the system? If yes, why; and could this be solved without the system? Will this system impact production efficiency in any way?

What measurable cost improvements will happen as a result of the system, and will they justify the costs?

"Be careful not to overspend on technology in an attempt to oversimplify the business information flow," says Cooper, who formerly managed operations at several RR Donnelley sites and also is GAM's best practices editor. "Also, beware of becoming a slave to a system where managing it becomes the focus over managing the business."

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Cooper says he has witnessed many instances where managers become overwhelmed with system information and the information system focus becomes bigger than the focus on the customer and on the business fundamentals.

"Systems become integrated into a business, and owners don't have good metrics to measure its true cost," says Cooper.

Such untabulated costs include the transition to a new system, the cost of training for and maintaining a new system, and the cost of keeping it current as technology evolves.

Automated scheduling requires use of an MIS system that can integrate to the scheduling system, but approximately 50% of U.S. printers run their shops with a custom-coded solution that can't connect with the new breed of scheduling systems, says Hal Hinderliter, director of the Graphic Communication Institute at Cal. Poly. and GAM's Workflow editor.

"We get calls from potential clients with their own shop floor and estimating systems that want to add our scheduling solution, but their current systems can't work with other software," says Vincent Lawrence, president of Graphic Arts IT, a scheduling system provider.

Many print shops execute scheduling through planning boards and static spreadsheet software. These methods get the job done, but automated scheduling systems offer a powerful tool to maximize throughput and resource allocation.

New breed of schedulers

A number of print management systems providers are stepping up with scheduling products newly linked to operations data systems. Leading the industry in installations is EFI, which gained numerous offerings in this area with the acquisition of the former PrintCafe. (Schedulingspecific offerings are distinguished in this report from broader capabilities seen in enterprise resource planning systems or ERPs.)

"Most companies view scheduling only as a tool to make sure jobs are on time and know what customer service can promise the customer," says Udi Arieli, product management director of CIM and product manager for PrintFlow, EFI's scheduling module.

Another barrier is that the classic "scheduling board" tends to be under the direct control of the plant owner. Lots of them are wary of technology. "They know that digital automation is good for other processes in their shop," says Hinderliter, "but don't want to lose control over the scheduling. Of course, an automated scheduling system can actually give them more control, but that's a hard sell."

Arieli contends that while manual scheduling using a white board works, it is not the optimal tool. Why? Because after managers spend time scheduling work, when it is time to print the job, the status of everything may have changed by the time a job reaches production.

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"Magnetic boards are good visual aids," acknowledges John Fleming, president of print- LEADER Software. But reports generated from a scheduling system provide a picture of what is actually happening.

Print management systems providers are stepping up with scheduling software linked to opeartions data. Cyrious rolled out a new version of its Control 3.0 scheduling system.

The Sheridan Group was an early adopter of automated scheduling. The $287 million publication printer evaluated a lot of scheduling systems, but found many operated as electronic versions of white boards, says Douglas Ehmann, VP and chief technology officer of the Hunt Valley, MD firm.

Arieli, whose AHP Systems was acquired by PrintCafe (and later became part of EFI) is viewed by some experts as the "Renaissance Man" of automated scheduling, in part for his development of the Theory of Global Optimization, based on familiar operations theory of constraints concepts, as applied to print manufacturing.

In a nutshell, the Theory premises that all steps in all areas of the print production process must be optimized and synchronized to achieve maximum throughput. Any changes in the scheduling of a single job affects all jobs and, ultimately, all production capacity.

"A print manufacturing operation is a chain of interdependent links," Arieli explains. "A change in any job step can affect all other steps of that job, as well as other jobs in the queue or in process," he says. Each job follows a linear process through the shop, says Arieli, but the mix of all jobs presents a dynamic and constantly changing picture.

"Achieving maximum throughput is the only way to increase profitability in a business that consists mostly of fixed costs," says Arieli. The profitability of a company is created by the sum of all its jobs, he says, not the theoretical profitability of individual jobs. This means that throughput is far more important than job costing or cost accounting.

Printer LAgraphico, Burbank, CA, 185 employees and $30 million in sales, increased throughput by 10% to 15% after implementing EFI's PrintFlow scheduling system.

"We were using a typical magnetic scheduling board that was rarely up to date, and too many people were constantly changing things," says Bill Jacot, VP manufacturing. "With PrintFlow, our schedulers can control the workflow throughout the plant. Our project managers can schedule and prioritize jobs by date and time." They can view the schedule from their offices and see the loading for the whole plant, says Jacot. Because the scheduler is integrated into the LAGraphico's MIS system, managers can determine in advance if the company will make deadlines or if renegotiation is needed.

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Automated scheduling systems hold the potential for production managers to fill capacity above budgeted hourly rates for time and to improve contribution—by as much as 20%, says Graphic Arts IT's Lawrence. "A good system shows where there is available time to pack jobs and identifies bottlenecks so managers can redistribute work and eliminate overtime."

Scheduling also influences a print shop's ability to grow. "There is a greater emphasis on scheduling as a business moves up the size continuum because more structure is needed to manage operations," says Scott St. Cyr, CEO of Cyrious Software. "Every time sales doubles, your operational systems have to fundamentally change."

Cyrious just rolled out a new version of its Control 3.0 scheduling system. Before founding the company, St. Cyr owned five rapidlygrowing sign printing shops. He developed an automated scheduling system to accommodate business growth.

Automated scheduling can't be piecemeal, says Ty Tidwell, GM of Franklin Estimating Systems, which will launch a scheduling system in July to accompany its product line. "It needs to be tied to estimating and shop floor data collection."

The Sheridan Group also uses EFI's PrintFlow, which the firm's Doug Ehmann describes as "a rule-based system with powerful algorithms that duplicate many of the processes an experienced and talented scheduling person would use. It's fast and can consider many more constraints and options than are humanly possible", he says. "We investigated other technologies to help us with scheduling but, until PrintFlow was developed, none could manage in real-time our very complex and critical production processes," he notes.

He says PrintFlow reduces production costs by smoothing the workflow and maximizing operational resources prone to form bottlenecks in a plant. "We can quickly consider the timing impact of different production alternatives—like using different equipment, and changing labor and shifts," reports Ehmann. Sheridan uses EFI's shop floor data collection module to feed real-time machine activities into PrintFlow. With it, "We can have up-to-date job status for even better on-time performance," notes Ehmann.

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M1 Scheduling identifies your shop floor capacity problems at a

glance.

M1 Scheduling is designed to provide manufacturers with pertinent information to enable improved delivery performance.

Backwards and Forwards scheduling of individual or multiple jobs provides better control over your shop floor. Extensive screen enquires and reports allow you to better manage your bottleneck work centers. View the jobs scheduled in a work centre or a department.

M1 Scheduling identifies your shop floor capacity problems at a glance.

Shop Load Explorer

View available capacity to overload situations for each work center or department. Clearly

identified overloads and non-working days; drill down to scheduled jobs; user-defined buckets all make for a very effective scheduling tool.

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Scheduling

Jobs may be individually scheduled from within the job entry screen, or alternatively, schedule multiple jobs at one time from the scheduling module. Rescheduling multiple jobs is made easy through a single screen.

Work Centers

Define the characteristics of a work center by its crew size, number of machines and daily capacity. Each work center also has its own queue and move times as well as costing information.

Scenarios (What-if)

An unlimited number of scenarios can be created so any number of what-if cases can be examined. Once the best case scenario is found, it can be simply saved as the master schedule.

Work Center Load Levelling

Once an overload situation has been identified, it is simply a matter of selecting the relevant jobs or even the entire work center and allowing M1 to automatically use finite scheduling to level the load.

Planned Material Requirements

Job operations are integrated with material requirements to provide a detailed Planned Material Requirements report.

Multi Windows

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Multi-level Assemblies

All assemblies within a job are scheduled to come together for final assembly, providing powerful useability for make to order manufacturing companies requiring true multi-level BOMs.

Production Calender

M1 Scheduling uses your Production Calender to accurately forecast the duration of your jobs. Identify all non-working days for the shop floor to improve your scheduling management.

Shop Floor Data Collection

All changes made to your schedule are immediately reflected in the Shop Floor Data Collection module. This ensures shop employees have current data available when they need it.

Work Center Efficiency Report

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Work Center Priority List

The work center priority list is updated from the schedule, displays the jobs to be worked on in order of priority and bar codes may be included for these operations.

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Job Scheduling

INPUT OUTPUT

Input Description: A directed acyclic graph G=(V,E), where the vertices represent jobs and the the edge (u,v) that task u must be completed before task v.

Problem: What schedule of tasks to completes the job using the minimum amount of time or processors?

Excerpt fromThe Algorithm Design Manual: Devising a proper schedule to satisfy a set of constraints is fundamental to many applications. A critical aspect of any parallel processing system is the algorithm mapping tasks to processors. Poor scheduling can leave most of the expensive machine sitting idle while one bottleneck task is performed. Assigning people to jobs, meetings to rooms, or courses to final exam periods are all different examples of scheduling problems.

Scheduling problems differ widely in the nature of the constraints that must be satisfied and the type of schedule desired. For this reason, several other catalog problems have a direct application to various kinds of scheduling.

We focus on precedence-constrained scheduling problems for directed acyclic graphs. These problems are often called PERT/CPM, for Program Evaluation and Review Technique/Critical Path Method. Suppose you have broken a big job into a large number of smaller tasks. For each task you know how long it should take (or perhaps an upper bound on how long it might take). Further, for each pair of tasks you know whether it is essential that one task be performed before another. The fewer constraints we have to enforce, the better our schedule can be. These constraints must define a directed acyclic graph, acyclic because a cycle in the precedence constraints represents a Catch-22 situation that can never be resolved.

The best book available for this problem is Intelligent Scheduling by Mark Fox.

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