From this year I would start writing English contents in this site, from time to time, to those readers who are interested in the planning and management technologies.
My first article is a review of an interesting book:
“Handbook of Emergency Response: A Human Factors and Systems Engineering Approach"
Edited by A. B. Badiru and L. Racz, CRC Press, 08/2013. (ISBN=13:978-1-4665-1457-7).
Handbook of Emergency Response: A Human Factors and Systems Engineering Approach (Industrial Innovation Series)
I happen to know this book by an e-mail from Mr. Stephen A. Devaux, the author of Chapter 21. Mr. Devaux is a well-known project management consultant/researcher and has been creating various innovative ideas. But, why emergency response? The emergency rescue for disasters is an important mission, of course. However, it may not be relevant to project planning or scheduling. No one can plan or schedule disasters beforehand. It seems just a matter of quick response by police, firefighters or military, and should be covered by their routine work -- that was my first impression as an ordinary citizen.
I have learned from this book that my understanding was not correct, or, at least, insufficient. Disasters have wide varieties in time and special spans. Each emergency situation is different from others. It requires a good, precise response plan in quite a short timeframe of an early phase. Adequate and sufficient resources/tools/technologies need to be mobilized. In fact, emergency response is a project of very compressed form. And, true costs of this type of project are not money -- human lives. Therefore, Chapter 21 by Mr. Devaux is titled “Time is a Murderer – the cost of critical path drag in emergency response”.
“Critical path drag” and “drag cost” are metrics proposed by Mr. Devaux in recent years. A critical path is the longest path connecting from the start node to the end node of a project network diagram. It governs the overall project duration. The critical path drag indicates how many days each activity contributes to its entire project length, with taking the parallel activities into consideration.
Suppose an activity in the critical path has 10 days duration. If this activity can be removed, overall project duration normally becomes 10 days shorter. However, if parallel activities exists with the critical path, it does not always happen. If the parallel path has total float of 3 days, it means removal of the critical activity of 10 days turns the parallel activity chain into a new critical path, and thus gives us only 3 day reduction instead of 10. When we wish to shorten project duration, value of the critical path drag is a good guidance for us to judge which activity to tackle -- the ones with larger drags.
Mr. Devaux combined this drag metrics to the cost. It is the drag cost. It is calculated by the critical path drag multiplied by cost of project delay per each day. For instance, if an activity's drag is 3 days and project is constrained with delay penalty at $1,000 per day, then its drag cost would be $3,000.
Cases for emergency response are, however, a little more complicated. There is no simple 'delay penalty'. Instead, we have to consider incremental increase in damage to people or property for every additional hour. He introduces "Damage Control Time Chart" that can illustrate profile of damage along time (p.511). Using this chart together with activity network diagram, Mr. Devaux explains how to obtain drag cost for each activity. Using this technique, he demonstrates in a case study showing a proper planning could reduce rescue time and save 237 lives out of 909 mortalities in 16 hour crisis.
As we see here, logical and quantitative approaches have great values in the emergency response practices. This book is a comprehensive collection of methods and technologies with such approaches. Chapter 5 explains optimization in evacuation route planning wit OR techniques. Chapter 7 deals with optimization of helicopter mission. Chapter 17 (written by the editor themselves) describes the coordinated project systems approach to emergency response. This book also covers wide aspects of human factors that play very important roles in the emergency situations.
In Japan we experienced a big earthquake and consecutive tsunami, and even nuclear plant failure on March 11, 2011. We saw too many tragedies in the area, but some part of them could have been prevented or reduced if quick and proper plans/actions taken in the earliest timing. There were lessons from another big earthquake in Western part of Japan back in 1995, telling us that good coordination among public services is vital in the emergency response. Unfortunately, it seems that lesson has not yet been fully implemented in our country. What we lack here is a structured, systematic approach in governmental planning and operation. Yes, it is the operations research (OR) itself.
I recommend this book to those readers who are interested in the emergency response. This is not a handy guidebook but a compilation of papers by researchers and practitioners, still we can learn a lot about the systems approach.