Theses and Dissertations from UMD

Permanent URI for this communityhttp://hdl.handle.net/1903/2

New submissions to the thesis/dissertation collections are added automatically as they are received from the Graduate School. Currently, the Graduate School deposits all theses and dissertations from a given semester after the official graduation date. This means that there may be up to a 4 month delay in the appearance of a give thesis/dissertation in DRUM

More information is available at Theses and Dissertations at University of Maryland Libraries.

Browse

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    IMPACT OF DYNAMIC MESSAGE SIGNS ON OCCURRENCE OF ROAD ACCIDENTS
    (2012) Norouzi, Azadeh; Haghani, Ali; Environmental Science and Technology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Dynamic Message Signs (DMS) are key components of Advanced Traveler Information Systems to manage transportation networks, reduce congestion and improve safety through providing motorists with real-time information regarding downstream traffic conditions. While DMSs are intended to improve efficiency and safety of road networks, little has been done to study the effect of the signs on driver safety and their localized safety impacts. This thesis employs ground truth data as the basis to investigate the issue in State of Maryland in a four-year period (2007-2010). The results show no significant difference between the accident pattern in the proximity of DMSs and the onward adjacent segments. On-and-off study is also conducted on DMS operation status (on/off). The results converge with the previous analysis suggesting that there is no meaningful relationship between occurrence of accidents and presence of DMSs. Besides, statistical analysis on DMS characteristics and accidents in impact areas are performed.
  • Thumbnail Image
    Item
    EMPIRICAL ANALYSIS OF THE QUALITY, EFFECTIVNESS, AND LOCALIZED IMPACTS OF HIGHWAY DYNAMIC MESSAGE SIGN MESSAGES
    (2011) Fish, Robin Lee Wilson; Haghani, Ali; Civil Engineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The need to convey accurate, real-time travel information to road users has long been recognized by transportation engineers. One of the primary means to accomplish this is the operation of highway Dynamic Message Signs (DMS). Though utilized for over 50 years, the quality of messages used, their effectiveness in influencing traffic, and the localized impacts they have are not well documented. This thesis introduces Bluetooth traffic detection sensors as a new tool for evaluation of DMS message quality and resulting route choice decisions. In addition, highway speed sensors are used to determine whether DMS influence changes in local traffic speeds. The findings indicate DMS messages are generally accurate in communicating prevailing conditions and can influence the route choice behavior of drivers. The speed analysis indicated that certain messages have more influence on traffic than others, though the majority of messages do not negatively affect traffic speeds.