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In order to ascertain whether neighboring intersections can be effectively coupled on the basis of traffic behavior, observational information on vehicular platoons was collected at four sites in London, England. This information is analyzed with particular emphasis on the phasing or synchronization of neighboring inter-sections for minimum delay. At each of the four sites studied, arrival time data was collected at four positions downstream from the signalized intersection from which the vehicular platoons were emerging. This data gives a measure of how platoons diffuse as they move from one intersection to the next. The analysis indicates that the diffusion process can be taken into account in the setting of signals. In particular, total delay in vehicle-hours per hour of green as a function of offset time is calculated, and in turn, the optimal offset time that would minimize delay is shown to be a linear function of the distance from the issuing traffic signal. [ABSTRACT FROM AUTHOR]

In this paper the authors find the optimal allocation of servicing periods to a facility servicing N incoming traffic streams. In our model it is assumed that stream flows are deterministic, that there is a fixed amount of lime lost, τi , when the server switches attention from the ith to the i + 1st stream and that the objective is to minimize time average delay. [ABSTRACT FROM AUTHOR]

We consider a one-way street that intersects ii one-way (side) streets. Traffic approaching the first street is steady as are the flows on all side streets. Traffic signals are idealized as perfect on-off switches and traffic is treated as a fluid moving with a constant velocity on the main street. Total delay and total number of stops are evaluated for several types of signal coordination schemes. Some conclusions are: 1. For any given common cycle time and given splits at each inter- section, there is a choice of offsets (phases) that simultaneously minimizes both the total delay and stops, but it is not necessarily the one that produces a `through band' of maximum bandwidth. 2. There are signal settings for which some signals operate on half or a third the cycle time of other lights, which give a main Street delay equal to that for the optimal common cycle time setting but give less delay to the side street. 3. Similar models are commonly used to find maximum through bands for two-way traffic, but it is not obvious that this is a suitable objective even for one-way streets. [ABSTRACT FROM AUTHOR]

The article focuses on the progress of traffic law enforcement. Traffic law enforcement alone does not have to carry the full responsibility for meeting the challenge. The burden is shared by two other fundamental factors in an effective control program: Engineering and Education. But the enactment of good traffic laws, and their proper enforcement, constitute a basic and indispensable element of highway safety. Now, in the face of imminent traffic changes ahead, the responsibility is once more clearly outlined. It is not pleasant to think what may happen if traffic is not effectively controlled during the next few years. Traffic regulations suffer from the national habit of passing a law and then forgetting that "there is no law without a sheriff." To be effective in this country, any law must carry the clear sanction of the majority of citizens. Beyond that, traffic laws must also be uniform. Conflicting rules of the road among local, county and state jurisdictions are impracticable in modern traffic.

The article presents questions and answers related to traffic law enforcement. One of the questions is regarding whether a police officer, who sees a motorist go through a stop sign, have the right to commandeer a passing car for pursuit. The police officer can ask for the motorist's assistance but generally in petty misdemeanor cases the motorist need not obey the request. However, if it is a case of an escaping felon, then the statutes generally authorize the officer to get help from bystanders. Another question asked is whether a police officer can take a car which has been involved in an accident and subject it to a brake test against the owner's will. Unless authorized by law, the officer has no right to take the car and drive it off to a place where brakes may be tested just to see if a crime has been committed. Another question is regarding whether a citizen who finds his neighbor's car parked in front of his own garage entrance can arrest his neighbor. The citizen's right to arrest generally is less than that of a regular police officer. The citizen usually can arrest a felon without a warrant; but he cannot arrest an orderly misdemeanant without a warrant.

In this article Mr. Ferguson, Lecturer in Psychology at Otago University, and Mr. Geddes, National Research Scholar at the same University (now of the New Zealand Government Transport Department), describe an investigation into the beliefs of pedestrians regarding their visibility to motor drivers at night. They indicate that many pedestrians may greatly overestimate the degree of their visibility and suggest this as one of the causes of road accidents. Although the experiment was not conducted on a large scale the results serve to bring home a point of some practical importance. [ABSTRACT FROM AUTHOR]