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Collisions between birds and aircraft have caused loss of human life and millions of dollars worth of property damage. The advent of even larger planes may reduce airframe damage, but it seems doubtful that engine damage will be significantly reduced. Dealing with the problem biologically involves combatting the hazards caused both by birds on or near the ground at airfields, and by birds on mass migrations at altitudes up to several thousand feet above ground. Airports can be designed or altered to minimize their attraction to birds. The chance arrival of a flock of birds must be treated as an emergency with all available equipment and personnel used to ensure quick dispersal. The hazards caused by birds aloft must be dealt with by making it possible for aircraft to avoid the main bird flocks. Warnings of the immediate presence of birds can be given by air traffic control operators trained to recognize birds on their radar. The ability to forecast the probable presence of flocks of birds on migration is now being developed.

Examination of representative and recently declassified samples of imagery from the type of radar developed especially for reconnaissance and mapping purposes by the military, the Side-Looking Airborne Radar ("SLAB"), indicates that SLAB images look very much like medium-grade aerial photos and will serve the following types of geographic tasks even better. 1) Tasks which require an overview of subcontinental magnitude. 2) Tasks which require an overview in which careful timing is critical. 3) Tasks which require an overview with maximum economy of time and money.

In this paper the author has suggested the use of P-R sequences, to generate random phase characteristics of the currents fed to a phased-array antenna, together with a suitable (r, , ) gating system. A radar system built on this technique could also incorporate a correlator, without any difficulty, for better detectability of signals accompanied by noise. Key-words: P-R sequences, phased-array antenna, correlator, phase-modulation, range-gating. [ABSTRACT FROM AUTHOR]

There are two important problems that arise in the use of amplitrons, as broadband microwave amplifiers in high power radar systems with frequency agility.
The first one is to modify the conventional high vacuum tube modulator to obtain proper operation with good efficiency in case of very high power levels.
The second one is to modify the modulator circuit by increasing its output impedance and thus limiting the peak current variations in the transmitted frequency band.
In this paper analyses are made of both these Problems, some practical results are given, and the implication in actual transmitter design is examined. [ABSTRACT FROM AUTHOR]

This article discusses the problem of radio-location and air defence. Once the sound of an approaching aircraft is registered, the sound-locator equipment brought the searchlight to bear in the general direction of the target and the beam of light began to probe the night sky. Some two years later the British air defence exercises brought home these same doleful lessons though on a wider scale. The British interest in and development of radar has received very adequate coverage in both memoir and monograpbic literature. As for Germany, it fell to the German Navy to promote an interest between 1934-5 in work on radar for use in connection with gun ranging and also air surveillance.

Surveillance of a region is conducted by using a search system to detect targets and a tracking system or force to follow them. After the search system detects a target, the tracking force will attempt to gain contact, usually by a local search. Before the tracking force detects the target, and thereby completes transfer, contact may be lost by the search system. If recontact is made by the search system, the new contact will be used by the tracking force to localize its search for the target. As the local search by the tracking force proceeds, contact by the search system may be lost and regained a number of times. The probability of transfer is obtained under the assumption that the transfer rate decreases as the time since last contact by the search system increases. The particular problem considered is that of sea surveillance for submarines, in which the search system is a fixed field of sensors and the tracking force consists of mobile units, such as ships, aircraft, and helicopters. However, the model can be adapted to other transfer problems, such as the transfer of a contact by a search radar to contact by a tracking radar. [ABSTRACT FROM AUTHOR]

The article presents a report on long-term radar survey by American Documentation Institute Committee on Organization of Information. While long distance communication engineering may be a unifying concept, progress in this vast field cannot be described without further internal classification. A valuable addition to this source material was an annual report by a 1955 ADI Committee on Research and Development. It listed all United States research programs then known to the Committee. Two members of that committee are now connected with the NSF publication.

The article provides information on a study concerning the weather radar measurement of bird migration. It is known that radar becomes an important tool for the studies of bird migration. However, it is difficult to estimate bird densities from echo densities on the radar screen. The use of the Weather Bureau's new WSR-57 radar for bird migration research is also discussed. The shorter pulse of this radar has greater resolution but only detects birds when they are highly concentrated in the air. The fading of pulse radar signals reduces the number of perceptible returns because of the distribution of the numbers of targets among the radar.

The article presents information on the two Nobel Prize winners Edward Appleton and Robert Robinson in the United States. Both men are from the North country from which they have drawn various characteristics. Appleton works in elucidating how wireless waves travel made long distance radio communication the precision method for up-to-the minute international contact and led to the development of radar. Appleton is head of the Government organization which is responsible for the applications of science to national needs. Appleton's work has been noticed mainly in the United States where the signal honor of the Medal of Merit was given him for his early work on radar and for his services. Robinson has always held academical appointments, being Professor in Sydney, Australia and several British Universities. Robinson discovered a simple synthesis for tropinone, a substance that can be obtained from and converted into the plant alkaloids atropine and cocaine.

The problem of finding a binary pulse-compression code with arbitrary side-lobe levels is cast as a quadratically constrained integer program. Witzgall's algorithm is then applied, after a suitable manipulation, to put the constraints into a convex form. [ABSTRACT FROM AUTHOR]

The article offers news briefs related to civilian and continental defense in the U.S. In the first part of November 1955, the Committee Disaster Studies of the National Research Council met with Federal Civilian Defense Administration officials. Meanwhile, though the line of radar stations along the northernmost rim of the continent will be a joint undertaking, the country will be responsible for the construction and installation.

The article discusses on the significance of radar in air defense in the U.S. Robert Watson-Watt, a distinguished pioneer and authority in radar research describes radar in a nonscientific language on how it works, how it will be used and how it may be frustrated during the January Foreign Affairs. According to the author, the application of an early warning radar networks can possibly detect aircraft crossing in the U.S. The author suggests that is necessary to apply a special radar network for the interception control in which these two radar networks are necessary to the defense of the U.S. and to its economy.

The article presents news briefs in the United States. A recommendation was made by the Bureau of Customs and the U.S. Post Office Department for the revision of the Foreign Agents Registration Act of 1938. The Western Electric Company is constructing radar units along an arc 12,000 miles from the North Pole after being contracted by Air Research and Development Command of the Air Force.

The article focuses on the establishment of a research program designed for the improvement of scientific research for war preparedness. The Joint Research and Development Board was created to assure coordination between the war and navy departments in the U.S. The program supported improvement in research and engineering for guided missiles, biological warfare, radar and other modern instruments of warfare. The Atomic Energy Committee was one of the permanent committees of the Board. The Joint Research and Development Board was a five-member board consisting of navy and army members.