Showing papers on "Literature survey published in 1973"
01 May 1973
TL;DR: In this article, the heat transfer characteristics of single and multiple turbulent air jets impinging on flat surfaces have been studied by many investigators, and suggested correlations for use in the design of cooled turbine blades are noted.
Abstract: Heat transfer characteristics of single and multiple turbulent air jets impinging on flat surfaces have been studied by many investigators. Results of many of these studies are summarized. Suggested correlations for use in the design of cooled turbine blades are noted, and areas where further research would be advisable are identified.
144 citations
TL;DR: A literature survey of the measurement of the solubilities of the normal fatty acids, alcohols and alkanes has been carried out as mentioned in this paper, which has allowed the reliability of the data to be assessed and the most reliable values available to be chosen.
99 citations
TL;DR: A survey of research on the effectiveness of alternative instructional media can be found in this paper, where traditional classroom instruction (TI), instructional radio (IR), instructional television (ITV), programmed instruction (PI), and computer-assisted instruction (CAI).
Abstract: This survey provides an overview of research on the effectiveness of alternative instructional media. The media discussed are traditional classroom instruction (TI), instructional radio (IR), instructional television (ITV), programmed instruction (PI), and computer-assisted instruction (CAI). The effectiveness of these media is examined from a reasonably macroscopic point of view; the psychology of pupil-teacher interaction or the 'content variables' of ITV, to take two examples, are at a micro-level not considered. Achievement test scores constitute the measure of effectiveness most frequently used in this survey though, where available, results concerning the affective impact of the various media of instruction are included. Achievement test data, in most cases, were collected only on an annual basis, so they reveal no fine-grained detail about the learning process. Since this survey is relatively brief and its scope broad, a few caveats are in order. First, where literature surveys are available, their results have been cited to the extent possible and, frequently, original sources remain unchecked. Second, available knowledge of the effectiveness of the various media varies considerably; much more is known about TI and ITV than about the others. For this reason a survey such as this is inherently spotty in its conclusions. The third warning, related to the second, is that many of the evaluations fall short of (or lack entirely) scientific standards of analysis and reporting. For this reason, it was sometimes necessary to attempt to cull conclusions from essentially journalistic accounts of projects. Fourth, it should be noted that this survey is limited to instruction within a school setting. Finally, the survey excludes information on costs. Before beginning the literature survey, we present a paradigm for measurement of effectiveness and then discuss several less desirable alternatives that have actually been employed. In the surveys of the individual methods where adequate prior surveys are unavailable, results from a representative sample of individual evaluations are discussed.
97 citations
TL;DR: A positive correlation appears to exist between the capacity of a chemical to induce liver tumours in the mouse and its capacity to induce tumours at any site in the rat or the hamster.
Abstract: A survey of the available data in the literature was carried out in an attempt to verify the possible correlation between the capacity of a number of chemicals to induce parenchymal liver tumours in the mouse and their capacity to induce tumours in the liver and/or other organs in the rat and hamster. Data on 58 chemicals were collected. A positive correlation appears to exist between the capacity of a chemical to induce liver tumours in the mouse and its capacity to induce tumours at any site in the rat or the hamster. The strongest correlation is found when the chemical, given to adult mice, induces tumours of the liver and other sites in both sexes. The induction of liver tumours in the mouse by a chemical does not signify that the liver would be the target organ in the rat or the hamster. Among the 58 chemicals considered, seven are recognized or suspected human carcinogens. All were hepatocarcinogenic in the mouse and six were carcinogenic in the liver and/or other organs in the rat. Four were tested in the hamster and found to be carcinogenic.
95 citations
TL;DR: In this article, a literature survey gave preliminary evidence that large second phase particles were cracked under static loading and that these might subsequently be sources of fatigue crack initiation, while the more probably event was failure of the matrix-inclusion interface.
Abstract: A literature survey gave preliminary evidence that large second phase particles were cracked under static loading and that these might subsequently be sources of fatigue crack initiation. In order to determine more fully the effect of this type of inclusions on crack initiation bulk samples of 2024-T3 material were strained to 6, 8, 10 and 12% and subsequently reheat-treated. Reverse bending fatigue specimens were then prepared for crack initiation studies. Observations by optical microscopy showed that the prestrain had caused several voids at the inclusions partly by cracking of the inclusions while the more probably event was failure of the matrix-inclusion interface. It was shown that the voids were sources of fatigue crack initiation. Tests on as received material indicated initiation to occur also at inclusion clusters. Repeated polishing revealed the complex three-dimensional nature of the inclusions and its significance for the local direction of crack growth.
84 citations
TL;DR: In this paper, the authors present an assessment of the solution procedures available for the analysis of inelastic and/or large deflection structural behavior, and compare and evaluate each with respect to computational accuracy, economy, and efficiency.
Abstract: This paper presents an assessment of the solution procedures available for the analysis of inelastic and/or large deflection structural behavior. A literature survey is given which summarizes the contribution of other researchers in the analysis of structural problems exhibiting material nonlinearities and combined geometric-material nonlinearities. Attention is focused at evaluating the available computational and solution techniques. Each of the solution techniques is developed from a common equation of equilibrium in terms of pseudo forces. The solution procedures are applied to circular plates and shells of revolution in an attempt to compare and evaluate each with respect to computational accuracy, economy, and efficiency. Based on the numerical studies, observations and comments are made with regard to the accuracy and economy of each solution technique.
77 citations
TL;DR: Analysis suggests that there is both phonological and semantic structure to the neurological representations of words in a number of aphasic syndromes, and it is shown that these paraphasias are by no means random substitutions.
70 citations
TL;DR: In this paper, a review of studies relevant to seat belt use, reported between 1960 and 1970 from England, Finland, Sweden and the U.S.A. is presented, concluding that the output from all the research activity on this problem area must be considered meagre.
65 citations
01 Jan 1973
TL;DR: The results of experiments in unsaturated soil indicate that survival of ecto-parasitic nematodes in fallow soil at pF values between 0.5 and 4 is not directly affected by soil moisture quantity, which confirms the general opinion that saturated soil is unfavourable for most nematode populations.
Abstract: Established nematode populations are very persistent in the soil. It is known that they need sufficient soil moisture for movement, feeding and reproduction (fig. 5), and that there are adverse soil moisture conditions which they cannot survive. The influence of soil moisture on survival of nematodes and nematode populations is the topic of this study. The investigations are made under laboratory conditions and are concentrated on ectoparasitic root-infesting nematodes, particularly Tylenchorhynchus dubius and Rotylenchus robustus, in fallow soil and in vitro. The animals chosen represent the large group of unspecialized plant-parasitic nematodes, which pass their entire life in the soil and which do not possess any apparent mechanisms against drought. All investigations on populations have been carried out with natural soils and their indigenous nematode populations (2.1.1. and 2.2.1.). The gross relationships between the three major soil phases and nematodes are summarized in figure 1; the nematodes themselves, though numerous, may be neglected as a factor in soil formation or as a soil component. Figure 2 lists the various soil moisture potentials which may affect nematode survival. The relationships between pF value and soil moisture content (figs. 3 and 6) and between pF' value and relative humidity of the air (fig. 4) are discussed as tools in this study (see also chapter 2). Distinction between soil moisture quality and quantity, and regarding the latter between three essentially different situations, viz. water-saturated soil, unsaturated moist soil and dry soil, appeared to be useful. The limit between unsaturated and dry soil cannot be indicated accurately with respect to nematode biology, because essential data about the physical and chemical properties of nematodes are lacking. The limit may vary for different species, stages of development or even individual nematodes (1.3.3.). The extensive literature survey (chapter 1) shows that many incidental data are available, but the information is yet too erratic to draw a coherent picture of the relations between soil moisture and nematode survival. This is particularly so because quantity and quality of soil moisture are often not considered separately. One conclusion may be that nematodes generally are proof against moisture conditions which both chemically and physically differ widely from their normal average environment. Reduced activity is the first visible symptom of a reaction to environmental stress, which may affect various species differently (1.2.). In water-saturated soil, nematode populations were reduced to about 20 % after 20 weeks (fig. 9) and there were indications that considerable reduction had occurred already after 12 weeks. This confirms the general opinion that saturated soil is unfavourable for most nematodes due to chemical properties of the soil solution as a result of microbiological activity (1.3.1). The results of experiments in unsaturated soil indicate that survival of ecto-parasitic nematodes in fallow soil at pF values between 0.5 and 4 is not directly affected by soil moisture quantity (figs 10, 11A and 12A). This can also mean that these nematodes are not or hardly active in moist fallow soil (3.3). Under such conditions also the quality of the soil solution, as influenced by normal manuring, has no measurable influence on survival of populations (figs. 11 B,C and 12B,C). Great qualitative modifications by excessive dressings with chemicals may cause damage (table 15), as indicated in the literature (1.3.2). Drought is generally considered harmful to nematodes and especially to ectoparasites, although in literature several cases of drought-tolerance in such nematodes are mentioned (table 1). When investigating the response of nematodes to desiccation, the graduality of the processes of dehydration and rehydration appear to be most important. Dehydration must proceed gradually, particularly for in vitro studies, because nematodes are killed by unnatural, rapid loss of water. For that purpose three slightly different desiccation techniques have been developed, making use of the relationship between the concentration of aqueous glycerine solutions and the relative humidity of the air in a closed room (2.3). Rehydration of desiccated nematodes and regaining activity thereupon requires time. This necessitates the application of adapted methods for the extraction of nematodes from dry soil, because otherwise only a fraction of the living nematodes would be caught (figs. 13 and 14). Experiments in soil as well as in vitro have demonstrated that ectoparasitic root- infesting nematodes generally are drought-tolerant to a certain extent (figs. 16, 17A, 19, 20). As already mentioned, desiccation survival depends on the rate of water loss (table 11), but also the degree and duration of desiccation are important (figs. 20 and 21). Diurnal changes of the relative humidity of the soil air aid nematodes to survive (table 12). Both experiments in vivo and in vitro showed great differences in drought-tolerance between nematode species (figs. 16, 17A, 19-22) and also between various stages of development (figs. 17B and 22). The general assumption that nematode eggs are important for restoration of populations upon severe drought, as a result of their exceptional drought-resistance, is contradicted by the experimental results for ectoparasites 4.3.2. and 5.7). Regarding the influence of chemical properties of soil moisture in dry(ing) soil, more research, distinguishing primary and secondary effects, appears to be necessary. The experimental results indicate fundamental differences, viz. increased drought-tolerance of one species and intoxication of another species under the same conditions (fig. 19, table 14), and also that loss of water in a dry atmosphere affects nematodes other than loss of water to a surrounding solution (5.10). Systematic differentiation of the reactions of nematodes to drought or any other environmental stress, analogous to systems used for plants, seems to be useful (5.10). Eradication of ectoparasitic root-infesting nematodes in fallow soil merely by maintaining non-extreme soil moisture conditions is hardly possible (figs. 9, 10, 11). Under extreme moisture conditions nematodes can be eradicated, but the process requires a long time (table 8, figs. 9, 16, 17, 19). However, partial nematode control with about 80% mortality, which is comparable with the effect achieved by chemical control, is considered sufficient for safe crop growth. In rapidly and strongly desiccated soil (pF 5.5) 80 % mortality can be achieved in a rather short period of time. For a number of susceptible species, such reduction occurred in 4 weeks or less and for more tolerant species the period varied from 10 to more than 24 weeks (table 8, figs. 16, 17, 19). Long lasting periods of severe drought occur in and and semi-arid areas (4.4). Efficient control of nematodes by dry fallow, possibly in combination with soil tilling at the right time, seems to be possible in these areas.
46 citations
TL;DR: In this article, a unified system of approximate equations and correction factors is proposed to adjust all elastic properties of wood for variations in specific gravity, moisture content, temperature and strain rate.
Abstract: Rational utilization of wood highes on adequate knowledge of its behavior under a wide range of conditions. Based on a literature survey, a unified system of approximate equations and correction factors is proposed. These enable one to adjust all elastic properties of wood for variations in specific gravity, moisture content, temperature and strain rate. Predicted values should be considered as useful guides to typical softwood behavior.
41 citations
TL;DR: A bibliography of chemical laser publications covering the period 1964 through 1971 has been compiled and shows the chemical systems exhibiting laser action and by an alphabetical author index.
Abstract: A bibliography of chemical laser publications covering the period 1964 through 1971 has been compiled. The chronologically listed references are followed by tables showing the chemical systems exhibiting laser action and by an alphabetical author index.
TL;DR: Efforts to prevent physician suicide should begin in medical school, where students should explore their inner conflicts and unsatisfying social interactions, and psychiatrists should prepare themselves to endure the irrationalities of their patients and the burden of isolation in their professional practice.
Abstract: The author's literature survey suggests that the incidence of suicide among psychiatric residents is probably similar to that among residents in other specialties and may not be very different from that of other males in the same age group. However, the problem merits attention not only because lives are being wasted, but because psychiatrists and other physicians are in short supply and their importance to the community is considerable. The author believes that efforts to prevent physician suicide should begin in medical school, where the students should explore their inner conflicts and unsatisfying social interactions. During their residencies psychiatrists should be helped to prepare themselves to endure the irrationalities of their patients and the burden of isolation in their professional practice.
TL;DR: A literature survey of the electrodeposition of the precious metals is reported in this article, where the fundamental aspects of the kinetics are assessed in the light of recent progress in metal deposition studies.
TL;DR: In this paper, a literature survey was carried out, revealing that while faults and seams constitute a major cause of instability underground, there is only a limited amount of information on behavior characteristics of gouge material.
TL;DR: An extensive literature survey is followed by description of the basic deterministic planning model—a model emphasizing the interactive consequences of cropping pattern selection, conjunctive use of ground and surface water, and employment of wells as water table control devices.
Abstract: Certain concepts and techniques of systems analysis can assist irrigation planning in poor countries with social and physical environments different from those of industrialized nations. An extensive literature survey is followed by description of the basic deterministic planning model—a model emphasizing the interactive consequences of cropping pattern selection, conjunctive use of ground and surface water, and employment of wells as water table control devices. Stochastic parameters are introduced into the model in order to improve the model's robustness of representation of reality and in order to interpret the consequences of stochastic variability meaningfully. Various factors favor the use of the chance-constrained approach to stochastic programming. Unlike previous applications, general distribution functions, variable capacities, piecewise linear decision rules, and stochastic demands and supplies are dealt with.
TL;DR: In this article, the decay of observed delayed proton and alpha precursors are summarized in tabular form, including the precursor half-life, its total available β-decay energy, the separation energy of the particle (proton or alpha) from the emitter, the probability for particle emission, the reactions used experimentally to produce the precursor, identification methods for some precursor, the energies and relative intensities of prominent particle groups emitted in the decay, and a complete reference list.
01 Nov 1973
TL;DR: In this paper, a survey of state-of-the-art seat-man modeling for impulsive loading consisting of work done by Cornell Aeronautical Laboratory, Jack Collins and James Turnbow is given.
Abstract: A brief discussion of the various inputs that affect ride quality and the need for ride quality criteria is given. Isolation of the human in any vehicle from undue vibration is an important criteria for ride comfort. Some current passive isolation systems are discussed in the context of seat-man models for automobile vibration isolation. Usual passive isolation systems use a combination of linear springs and viscous damping elements. Active vibration isolation through the use of feed-back controls using relative displacement or accelerations on tractor seats by C.W. Suggs and L.F. Stikeleather and jet transport seats by P. Calcaterra is discussed. In conjunction with both the active and passive vibration isolation systems static comfort is maintained with seat cushions. Alleviation of compression fatigue can be achieved through moveable and adjustable seats and dynamic cushions. Human body mechanistic modeling by Coerman, Dieckman, Stanley Aviation, and Suggs is presented. Experimental parameter determination of the limped mass models of the human through the use of mechanical impedance is discussed. Recent modeling by Jex and Allen of the human through behavioral techniques for research into operator control capabilities in a dynamic environment and its potential for correlation with subjective ride quality measurements is discussed. A survey of state of the art seat-man modeling for impulsive loading consisting of work done by Cornell Aeronautical Laboratory, Jack Collins and James Turnbow is given.
01 Oct 1973
TL;DR: In this paper, a method was developed for identifying the transportation mode features or attributes that determine modal choices for specified trip purposes, and an estimate was made of the percentage of people using private cars who would be likely to switch to public transportation if it was improved.
Abstract: A summary is presented of actions undertaken in the area of problem definition and research goal delineation, conferences with interested agencies and personnel, and a literature survey. Details are given of questionnaire design and pretesting (an exploratory questionnaire and a second questionnaire were administered to two samples of Austin residents). The analytical procedures used and on-going work and follow-up for future reports is disussed. A method was developed for identifying the transportation mode features or attributes that determine modal choices for specified trip purposes. A estimate was made of the percentage of people using private cars who would be likely to switch to public transportation if it was improved. Existing low-density (cars) and high-density transportation modes (buses) were evaluated to spot critical gaps between perceived features of buses versus cars, along determinant attributes of modal choice. Local media most utilized by potential high density rider 'converts' were determined and recommendations will be made with regard to advertising. The general community and a "leaders" subset was surveyed for attitudes towards high-density transportation and appropriate means of financing improvements.
01 Oct 1973
TL;DR: In this article, an attempt is made to IDentifiability service-ability criteria for the present stage of building construction, to determine the theoretical and experiential basis for these requirements and to evaluate the range of applicability of these requirements.
Abstract: THIS LITERATURE SURVEY AND STATE-OF-THE-ART STUDY ENCOMPASSES A BROAD AREA OF THE STRUCTURAL ENGINEERING FIELD; DEFLECTIONS OF BUILDING STRUCTURES OTHER TYPES OF STRUCTURES SUCH AS TOWERS, BRIDGES, ETC ARE BRIEFLY MENTIONED BUT PRIMARILY IN THE CONTEXT OF INFORMATION THAT MAY BE APPLICABLE TO BUILDING STRUCTURES THE REPORT WAS ASSEMBLED CONSIDERING BUILDING STRUCTURE DEFLECTION IN A SEQUENCE THAT WOULD BE USED WHEN CONSIDERING THE SOLUTION OF A STRUCTURAL DEFLECTION PROBLEM, IE, SEPARATION OF STATIC AND DYNAMIC DEFLECTIONS AND THEN CONSIDERING EACH OF THESE AS A THREE COMPONENT PROBLEM OF LOAD -- STRUCTURAL CHARACTERISTICS -- RESPONSE (DEFLECTION) THIS SEQUENCE IS DEVELOPED AND DEFINED FOR THE RESPECTIVE COMPONENTS THROUGHOUT THE REPORT ALSO THE INTERACTIONS OF MAJOR STRUCTURAL DEFLECTIONS WITH BUILDING STRUCTURES SUBSYSTEMS AND HUMAN OCCUPANTS IS REVIEWED IN THIS REPORT AN ATTEMPT IS MADE TO IDENTIFY SERVICEABILITY CRITERIA FOR THE PRESENT PRACTICE OF BUILDING CONSTRUCTION, TO DETERMINE THE THEORETICAL AND EXPERIMENTAL BASIS FOR THESE REQUIREMENTS AND TO EVALUATE THE RANGE OF APPLICABILITY OF THE EXISTING CRITERIA PRIMARY EMPHASIS IS ON THE IDENTIFICATION AND DOCUMENTATION OF EXISTING SERVICEABILITY PROVISIONS THE BIBLIOGRAPHICAL LISTINGS ARE NOT NECESSARILY A LISTING OF ALL AVAILABLE LITERATURE BUT RATHER A LISTING OF WHAT WAS CONSIDERED BY THE AUTHORS TO BE THE MOST PERTINENT THIS REPORT IS BROAD IN SCOPE AND COVERS THE AREAS OF ANALYSIS, DESIGN AND EXPERIMENTATION /AUTHORS/
TL;DR: A literature survey indicated some factors thought capable of causing a measurable change in corneal topography, with the exception of time and mechanical pressure, the evidence presented in the literature for some alleged effects is usually of doubtful validity.
Abstract: A literature survey indicated some factors thought capable of causing a measurable change in corneal topography. With the exception of factors such as time and mechanical pressure, the evidence presented in the literature for some alleged effects is usually of doubtful validity. Some brief experiments by the author indicate no measurable effect on corneal topography from accommodative effort or from turning the eye in a temporal direction.
TL;DR: The survey involved University Librarians, a sample of professionally qualified librarians who had held university library appointments, and as many graduate staff in university libraries without library qualifications as could be traced as discussed by the authors.
Abstract: The terms of reference of the Cambridge Library Management Research Unit included a proposal for research into the staffing of university libraries. Preliminary investigations based upon a literature survey revealed a shortage of adequate current data, and suggested a need for further information. It was therefore decided to carry out a survey of staff deploy ment; this took place in April 1971. The survey involved University Librarians, a sample of professionally qualified librarians who had held university library appointments, and as many graduate staff in university libraries without library qualifications as could be traced. The ressslts give the type of establishment, the numbers of appointments and resignations in recent years, the academic qualifications of librarians, their job expectations, reasons for movement, and professional development.In each section of the investigation it is hoped that results have emerged which will usefully complement the findings of the DES survey of manpower requirem...
TL;DR: In this article, a series of LABORATORY TESTS and a LiterATURE SURVEY were used to determine the relative density of individuals in relation to other individuals.
Abstract: ON THE BASIS OF A SERIES OF LABORATORY TESTS AND A LITERATURE SURVEY, THE MAXIMUM AND MINIMUM DENSITIES FOR THE DETERMINATION OF THE RELATIVE DENSITY OF SANDS INVOLVE RANDOM ERRORS FROM A FRACTION OF ONE PERCENT TO ONE PERCENT, AND SYSTEMATIC ERRORS REACHING SEVERAL PERCENT. CONCERNING RANDOM ERRORS IN DENSITY MEASUREMENTS, THE COEFFICIENT OF VARIATION OF THE RELATIVE DENSITY IS EXPRESSED AS A FUNCTION OF THOSE OF THE SPECIMEN DENSITY AND THE LIMITING DENSITIES. FOR GIVEN DISPERSION IN THE DENSITIES, THE COEFFICIENT OF VARIATION OF THE RELATIVE DENSITY INCREASES RAPIDLY AS THE RELATIVE DENSITY DECREASES. A NUMERICAL ANALYSIS OF THE INFLUENCE OF SYSTEMATIC ERRORS IN THE LIMITING DENSITIES ON THE RELIABILITY OF THE RELATIVE DENSITY SHOWS THAT THE RELATIVE DEVIATION IN THE RELATIVE DENSITY MAY REACH TENS OF PERCENT IF ARBITRARY METHODS ARE USED. IN VIEW OF THE SENSITIVITY OF THE RELATIVE DENSITY TO VARIATIONS IN THE DENSITY MEASUREMENTS, THE NEED FOR RIGIDLY STANDARDIZED TEST METHODS FOR THE LIMITING DENSITIES IS EMPHASIZED, AND CRITERIA FOR THE STANDARD METHODS ARE SUGGESTED. /AUTHOR/
01 May 1973
TL;DR: In this paper, the results of a four-phase study to develop helicopter structural crashworthiness analytical and design techniques are presented, which consisted of the development of a computer program (KRASH) and the verification of a mathematical model to predict the dynamic response during a survivable accident in which combined vertical and lateral impact velocities are present.
Abstract: : The results of a four-phase study to develop helicopter structural crashworthiness analytical and design techniques are presented. The study consisted of the development of a computer program (KRASH) and the verification of a mathematical model to predict the dynamic response during a survivable accident in which combined vertical and lateral impact velocities are present. Included in the study were a literature survey and evaluation, a detailed analysis of 32 accident cases, a drop test of a UH-1H helicopter with ground impact conditions of 23 fps vertical velocity and 18.6 fps lateral velocity, and parameter studies. It is concluded that program KRASH is capable of accurately predicting the dynamic responses during a multi-directional accident and that the program is a valuable tool with which to perform design tradeoff studies.
01 Jan 1973
TL;DR: A survey of the research concerned with the dynamics of single, conventional railway vehicles is presented in this article, focusing on analytical research and experimental research performed in conjunction with analytical efforts, and the often conflicting objectives for railway vehicle suspension design and the research done to understand the design implications of these objectives are discussed.
Abstract: A survey of the research concerned with the dynamics of single, conventional railway vehicles is presented. Attention is concentrated on analytical research and experimental research performed in conjunction with analytical efforts. The often conflicting objectives for railway vehicle suspension design and the research done to understand the design implications of these objectives are discussed.
TL;DR: A literature survey revealed many aspects of the bricklaying process, in which previous work had shown improvements to be potentially possible but limitation of funds caused attention to be focused on the manual methods employed by the bricklayer himself as mentioned in this paper.
TL;DR: In this article, a literature survey shows that efficiencies of columns incorporating film contacting devices often decrease very significantly in the low composition range, and it is suggested that this behaviour is caused by wetting changes occurring in this region.
01 Jan 1973
TL;DR: In this paper, the response to a nationwide questionnaire survey was analyzed in an attempt to determine and characterize guidance information needs and driver-peered guidance problems in urban areas, and the results of the survey were then used to prepare a list of recommendations.
Abstract: Previously developed highway information system research techniques were used to assess the State of the Art of Urban guidance and to study means of Urban guidance and to study means of overcoming existing deficiencies. Recently published literature was surveyed and technical discussions wer conducted with experts and operational personnel. The response to a nationwide questionnaire survey was analyzed in an attempt to determine and characterize guidance information needs and driver-pereceived guidance problems in urban areas. Guidance missions were conducted in representive urban areas and case studies were prepared. The results of the foregoing studies were then synthesized, and problems and potential solutions were identified. A representative urban area was then selected and the problem-solution pair was applied. The problem-solution pairs were evaluated in laboratory simulation. The results of the research were then used to prepare a list of recommendations. The published literature in system elements, systems considerations and user-perceived problems and needs is reviewed. Study inputs yielded in the synthesis of the State of the Art (including both the literature survey and technical discussions) are listed. A summary is presented of a study of the 1971 edition of the Manual on Uniform Traffic Control Devices. Details are given of the purpose and methodology of the case studies in urban guidance. The questionnaire survey is described and signing solutions are discussed. The empirical evaluation of some signing solutions are reviewed. The results of the study are interpreted and discussed in the light of system deficiencies and alternate or revised solutions. Conclusions regarding the scope of the urban guidance problem and recommendations relating to the problem are presented. The applications of the research are discussed and areas of research are suggested.
TL;DR: The use of highly conjugated organic polymers as heterogeneous catalysts is reviewed as part of a series of papers relating to their use in reactions involving oxides of nitrogen as discussed by the authors.
Abstract: The use of highly conjugated organic polymers as heterogeneous catalysts is reviewed as part of a series of papers relating to their use in reactions involving oxides of nitrogen. The polymers which have been examined and the types of catalysed reaction so far recorded are described.
In general the structural features, including extensive conjugation, which are considered important for catalytic activity and selectivity, are also responsible for their high thermal stability. The presence of hetero-atoms, a high stable concentration of delocalised electrons and semiconductivity, have each been proposed as primary requisites for catalytic activity.