The Golden Hour

By Gerard Cachon and Christian Terwiesch, The Wharton School at the University of Pennsylvania. Source: Matching Supply with Demand.

Christian Terwiesch

Gérard Cachon

Sirens and speeding ambulances are the symbols of emergency care. The basic idea is that the sooner we get seriously injured trauma patients to the hospital, the bigger the chance of their survival. The first 60 minutes after an accident are known as the “golden hour”. Getting the patient to the hospital in this golden hour is claimed to be critical. This is intuitive. But, unfortunately, this claim is not really supported by a whole lot of empirical data. In fact, the authors (who are ER physicians) of a recent Slate story discuss the statistical evidence supporting the myth of the golden hour. They discuss a recent study published in the Annals of Emergency Medicine that finds no support for the importance of extra speed.

But why then, are the ambulances driving so fast? From an operations management perspective, two explanations come to mind. First, the fact that an extra couple of minutes do not matter much in predicting patient survival rate does, of course, not imply that the driver can stop at the next Starbucks… Second, there might be an alternative explanation for the speeding ambulance. Let’s call it the NY cab driver syndrome: The faster you drive, the sooner you will be available for the next trip. After all, it is all about productivity.

Advertisements

Green buildings, LEED, and energy efficiency

By Anna Nargurney, Isenberg School of Management at the University of Massachusetts Amherst. Source: RENeW.

Dr. Anna Nagurney

Did you know that buildings consume 70% of the electricity used in the US? Although there has been clear progress in terms of making appliances more efficient, an enormous amount of energy is still wasted in buildings. Equipment may be left operating when it is not needed, air conditioners may be running full blast where there are no occupants, and mechanical and electrical infrastructure may become less efficient over time.

When one considers how much time humans spend in buildings it is imperative that research into sustainable buildings receives full consideration and support.

Alec Appelbaum has an excellent Op-Ed piece in The New York Times, “Don’t LEED Us Astray.” LEED, which stands for Leadership in Energy and Environmental Design, is a program which awards points for incorporating eco-friendly material and practices into buildings’ design and construction. It has brought great attention to environmental awareness from the buildings and construction sector, as well as from consumers.

The United States Green Building Council gives out the LEED certification, with the highest level being “platinum,” and such certification has now become the most-widely used green building measure in the US.

Appelbaum, in his article, notes that much more should and could be done regarding the LEED certifications, since they provide a snapshot of a building at a point in time. According to Appelbaum, and I concur: some certified buildings end up using much more energy than the evaluators predicted, because the buildings are more popular than expected or busy at different times than developers forecast, or because tenants ignore or misuse green features. The governmentshould institute regular audits or “check-ups” to ensure that the certified buildings are performing energy-wise, as certified. Those who perform well may get tax credits or even subsidies for outstanding performance.

I would argue that one needs to capture the entire life cycle of the building (clearly a challenging research and practical problem, but manageable). In order to do this, we need to develop green building supply chain design models. We have, recently, taken a step in this direction with our study, “Sustainable Supply Chain Network Design: A Multicriteria Perspective,” which is forthcoming in the International Journal of Sustainable Engineering.

Given how much time people spend in buildings and, hence, how important buildings are to our health and well-being, and that of the environment, we, as a nation, need to push the frontiers of energy research in this direction.