1,905 research outputs found
Techniques for Forecasting Air Passenger Traffic
The basic techniques of forecasting the air passenger traffic are outlined. These techniques can be broadly classified into four categories: judgmental, time-series analysis, market analysis and analytical. The differences between these methods exist, in part, due to the degree of formalization of the forecasting procedure. Emphasis is placed on describing the analytical method
Development of the Air Transport Industry
The major developments are outlined in the U.S. scheduled air transport industry both domestic and international, together with a brief history of the European air transport system. The role and formulation of the U.S. Civil Aeronautics Board, International Civil Aviation Organization, and International Air Transport Association are also covered
The impact of changing technology on the demand for air transportation
Demand models for air transportation that are sensitive to the impact of changing technology were developed. The models are responsive to potential changes in technology, and to changing economic, social, and political factors as well. In addition to anticipating the wide differences in the factors influencing the demand for long haul and short haul air travel, the models were designed to clearly distinguish among the unique features of these markets
The Market Demand for Air Transportation
Although the presentation will touch upon the areas of market for air transportation, the theoretical foundations of the demand function, the demand models, and model selection and evaluation, the emphasis of the presentation will be on a qualitative description of the factors affecting the demand for air transportation. The presentation will rely heavily on the results of market surveys carried out by the Port of New York Authority, the University of Michigan, and Census of Transportation
Impulse Voltage Breakdown Strength vs. Temperature of Octafluoropropane (Ca Fa) Gas Exposed to Uniform and Non-uniform Fields
The purpose of my thesis is to investigate the impulse voltage breakdown strength of Octafluoropropane gas as a function of the temperature of the gas. The standard 1.5 x 40f4sec. positive polarity impulse waveshape was used in alt the tests. The investigation was made with and without a weak source of irradiation present near the eel I. Two types of electrode systems were used: three fourth inch sphere to grounded plane which represented a fairly uniform field, and a point to grounded plane representing a highly non-uniform field. The tests were carried out to room temperature to a temperature of 150°C. The impulse ratios of the gas was also plotted using some of the data from Roman\u27s thesis. Impulse Ratio is defined as the ratio of the impulse crest voltage strength and the crest value of 60 Hz one-minute voltage withstand test. It is a very important factor for designers from an insulation co-ordination point of view
A retrospective study of post-partum intrauterine contraceptive devices in a government maternity home of Delhi
Background: Post-partum period is defined to be an ideal time for family planning counselling. Being a second largest populated country, India has a high rate of unintended pregnancy especially in post- partum women. There is a need for accessible, reliable contraception like post-partum intra uterine contraceptive device (PPIUCD) in our country. The present study is an attempt to evaluate the safety and efficacy of intra- uterine devices in post-partum women.Methods: The study population included all the women who delivered vaginally who were counselled for PPIUCD insertion in prenatal period, early labour and within 48 hours of delivery and were willing to participate in the study. Participants were interviewed prior to discharge after receiving a PPIUCD and then six, ten, fourteen weeks and 6 months or earlier when necessary. Institutional ethical approval and informed consent were taken.Results: A total of 1625 deliveries took place out of which only 888 were inserted PPIUCD. So, the total acceptance rate was 54.6%. Majority of cases were between the age group of 21-25 (46.4%) and most of them were primipara (39.8%). 34.8% came for routine follow up in OPD at 6 weeks, 14% at 6 months and 6.1% at 1 year.Conclusions: The IUCD insertion has been proved to be a safe and effective method of contraceptive with very few side effects and no major complications. To increase the knowledge and skills among health care providers, it is necessary to arrange training on PPIUCD
Aircraft requirements for low/medium density markets
A study was conducted to determine the demand for and the economic factors involved in air transportation in a low and medium density market. The subjects investigated are as follows: (1) industry and market structure, (2) aircraft analysis, (3) economic analysis, (4) field surveys, and (5) computer network analysis. Graphs are included to show the economic requirements and the aircraft performance characteristics
Simplified extraction of good quality genomic DNA from a variety of plant materials
Depending on the nature and complexity of plant material, proper method needs to be employed for extraction of genomic DNA, along with its performance evaluation by different molecular techniques. Here, we optimized and employed a simple genomic DNA isolation protocol suitable for a variety of plant materials covering in vitro grown tender plantlets to relatively complex plant tissues such as field grown mature potato leaves and tubers. Unlike other methods, no detergent was included in the isolation steps. This protocol, based on Dellaporta’s method as reported earlier, worked efficiently both at small and miniscale during handling large number of plant materials. DNA yield was found to be in the range of 70 to 120 μg per gram of the plant material; sufficient for most of the molecular techniques. Purity of DNA was checked by A260/A280 ratio, and restriction analyses including the isoschizomers HpaII and MspI. The DNA preparations were successfully used in polymerase chain reactions using genespecific primers for cloning of different genes. Prolonged storage did not affect the quality of the DNA samples. Taken together, this method could be a reliable substitute to frequently used chemical cetyl trimethylammonium bromide (CTAB) and commercial kits-based plant DNA isolation protocols.Key words: Plant materials, genomic DNA isolation, restriction analyses, HpaII and MspI isoschizomers, genespecific primers, polymerase chain reaction (PCR), molecular cloning, DNA storag
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