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Source: Albuquerque Journal, N.mini storageM.Oct. 14--WHY, IN 2013, ISN'T TRAMWAY SYNCHRONIZED? Now that Bernalillo County is testing a new traffic signalization system on Alameda and has eyes to expand it to Tramway, drivers who simply want their signals synched may be wondering if it will really make commutes smoother.Jim Orr emails "in this day and age of computers and simulators, Tramway is a mess." His questions include what criteria was used in the original design for Tramway traffic flow; why didn't it include medians where pedestrians could safely wait; how do the signals accommodate morning vs. evening rush hour as well as traffic on weekends, nights, holidays, etc.; what speed will get a driver to hit all greens and why isn't it posted; and will there be public hearings concerning the new adaptive signalization system and how will the public know it's working?Whew. While Tramway covers multiple jurisdictions, David Mitchell, Bernalillo County's Operations and Maintenance director, says "in a nutshell, (much) of Tramway was built by the New Mexico Department of Transportation in the 1970s with traffic signals and standard highway details developed in the 1950s. That was state of the art." The design of median refuges for pedestrians, etc., "that's been evolving in the 1990s."To prove the point, consider Tramway has a wooden pedestrian bridge that you can see from the windows of homes straight out of "The Brady Bunch."But back to signal synching. Mitchell says there are signal programs in place on Tramway for nights, weekends and morning and evening rush hours, "but those presets don't adapt" to side-street traffic or pedestrians. Right now the speed Jim seeks for synchronization is the speed limit, but one car or pedestrian can throw a wrench into the timing.Yet as a recent column pointed out, the county is seeking funding to bring an adaptive signalization system to Tramway, the same system it is currently testing on Alameda and one more like what Jim is seeking.A PRIMER ON ADAPTIVE SIGNALIZATION: Mitchell says "what adaptive signals basically do is behave like a simple side-road detector system on steroids. Adaptive uses sensor cameras for the main and side streets to act like there's 30 or 40 loop detectors (magnetic sensors that detect traffic at the painted white stop bar) in advance of the intersection and is constantly counting how many cars are waiting, not just whether one is present at the line."The most simple signalization is 儲存 detector mode, where on a major street "all the lights will stay green unless someone pulls up on a side street and the light changes for them."The next kind is a coordinated/actuated corridor, what Mitchell says most folks consider synchronized, which "basically pre-programs the rush hours to ignore the side streets in favor of a rigid cycle that favors the main line."The newest development is adaptive, which "jumps back and forth between those two modes of operation," generally favoring the larger street but using any gaps on it to move cars on the side streets.But "there is a limit to what adaptive signals can do," Mitchell explains. "If it's over saturated from all directions, then there aren't any gaps to 'play with.' So a big crushing rush hour will still have a back up. What we think we are seeing (in the Alameda test) is that the adaptive can hurry up and get as many people through the side streets and maximize all the mainline as much as possible, before and after the big crunch, so that the length of time when the back up starts and ends is reduced. It makes the streets as efficient as they can be."ROAD DEATHS RISE IN JULY, DROP IN AUGUST: Traffic fatalities in New Mexico jumped to 33 in July, from 15 in June, then decreased to 25 in August, according to the statisticians at the University of New Mexico who keep tallies for the New Mexico Department of Transportation's Traffic Safety Division.In July, 21 of those deaths were in vehicles, one was on an all-terrain vehicle, six were on foot and five were on motorcycles. Alcohol was a factor in 14 of the deaths. Just nine of the vehicle occupants was buckled in.In August, 15 of the deaths were in vehicles, three were on ATVs, three were on motorcycles, two were on bicycles and two were on foot. Alcohol was a factor in eight of the deaths. Just one of the vehicle occupants was buckled in.And only one of the people killed on a motorcycle or ATV in those two months was wearing a helmet.Assistant editorial page editor D'Val Westphal tackles commuter issues for the Metro area on Mondays and West Siders and Rio Ranchoans on Saturdays. Reach her at 823-3858; road@abqjournal.com; P.O. Drawer J, Albuquerque, NM 87103; or go to ABQjournal. com/traffic to read previous columns and join in the conversation.Copyright: ___ (c)2013 the Albuquerque Journal (Albuquerque, N.M.) Visit the Albuquerque Journal (Albuquerque, N.M.) at .abqjournal.com Distributed by MCT Information Services迷你倉