Ing Capacity Research Articles

Investigação sobre a relação entre as características do terminal de passageiros aeroportuário e as receitas não aeronáuticas

Com os elevados custos associados do setor aéreo, os aeroportos enfrentam um grande desafio que é o de maximizar suas receitas. Para isso, nota-se que a ampliação das receitas provenientes de atividades não aeronáuticas aparece como uma possível solução. Nesse contexto, o objetivo deste artigo é realizar um estudo econométrico sobre as receitas não aeronáuticas dos aeroportos da rede Infraero, a fim de entender sua relevância para o operador, e quais parâmetros influenciam a captação desse recurso. A partir dos resultados obtidos observou-se que a participação da Receita Não Aeronáutica (RNA) sobre a Receita Total aeroportuária é de 54% e que os parâmetros mais relevantes para explicar tal receita dessa natureza são: (i) movimento de passageiros, (ii) área do terminal de passageiros, (iii) capacidade do estacionamento e (iv) lojas após o controle e inspeção de segurança.

HCNG 엔진의 터보차저 변경에 따른 전부하 출력 및 배출가스 특성 연구

Hydrogen-natural gas blends(HCNG) engine is optimizing technology of performance and emission characteristics with use of hydrogen's fast flame speed and wide flammability limit. As lean-burn limit is extended, the improvement in thermal efficiency and harmful emissions can be achieved. However, the extension of lean-burn limit under a wide open throttle operation point could be realized with the increase in boosting capacity in a lean-burn engine with turbo-charging system. In the present study, the power output characteristics of HCNG engine with turbo-charger change is assessed and feasibility of the increase in boost- ing capacity is evaluated. The turbo-charger design with high efficiency at higher flow rate rather than higher boosting pressure makes efficient operation possible at relatively rich mixture condition.

SERPENTINE SOILS, ADVERSE HABITAT FOR PLANTS CASE STUDY AT PENINSULAR

The unpleasant effect of serpentine soil on plant l ife has been a topic of many studies for several de cades. Infertility and flora selectivity nature of serpent ine soils are the features, which made them of inte rest throughout the world. This research includes a geoc hemical study on two Malaysian serpentine massifs t o introduce their harmful factors concerning vegetati on. X-ray fluorescence results on 11 soil samples s howed that serpentine soils comprise large values of iron and magnesium (up to 55 wt and 65 wt% respectively) and high amounts of some heavy metals like chromium (1248-18990 µg g -1 ), nickel (189-1692 µg g -1 ) and cobalt (95-478 µg g -1 ). However, soil extraction by ammonium acetate solution revealed that only magnesium is plant available. Besides, serpentine soils are poor in so me major plant nutrients such as nitrogen, potassiu m and phosphorus. This substantial paucity is the main ca use of bareness in these lands. Soils in the studie d areas are moderately acidic and have the adequate cation hold ing capacity. Their Ca/Mg quotient is very low (les s than 1). The latter with the low availability of the cal cium (0.34 m-equiv 100 g -1 in average) is another challenging parameter in serpentine soils, which exerts negativ e influence on plant growing.

Effects of Some Soil Management Systems on Soil Physical Properties, Microbial Biomass and Nutrient Distribution Under Rainfed Maize Production in a Humid Rainforest Alfisol

Effects of Some Soil Management Systems on Soil Physical Properties, Microbial Biomass and Nutrient Distribution Under Rainfed Maize Production in a Humid Rainforest Alfisol

Synthesis of Neomycin Analogs to Investigate Aminoglycoside-RNA Interactions

A series of novel aminoglycoside oligosaccharide analogs containing a 2,5-dideoxystreptamine core scaffold was prepared to study aminoglycoside binding to the small subunit of 16S rRNA. A set of monosaccharide building blocks carrying amino groups in different positions and conformations around the pyranose ring was utilized in the assembly of oligosaccharides. These aminoglycoside analogs were analyzed for their RNA-bind ing capacity using a high throughput mass spectroscopy assay.

Occupational asthma caused by grass juice

J A LLERGY C LIN I MMUNOL 1995;96:693-5.

Vasomotor and sudomotor responses of human head skin during hyperthermia; strategy of prevention of heat stroke

Vasomotor and sudomotor responses of human head skin during hyperthermia; strategy of prevention of heat stroke

U.S. Dependence on Imported Nonfuel Minerals: The Threat of Mini-OPECs?

situation is rendered more ominous by the prospect of even greater import dependence in the future, as environ­ mental restrictions impede the main­ tenance of domestic smelting and refin­ ing capacity and the development of new mines. Does this mean there are crises impending in some nonfuel minerals? Will continued demand growth in the industrialized countries lead to the same scramble for supplies in a tight market ruled by an OPEC-like cartel now being witnessed in oil?! The U.S. import position in nonfuel minerals is not a recent development; we have been in this position since World War II. The military vulnerabil­ ity this constitutes was brought home with force during the war, when ma­ terials shortages developed. In 1946, a Strategic Stockpile was established to ensure that such shortages would not recur in any future war. Through the establishment of stockpile goals to provide for military support needs, the aim was to assure adequate supplies for the manufacture of materiel for a three­ year, conventional war.

The Effect of Temperature and Moisture Content on the Flexural Response of Kevlar/Epoxy Laminates: Part I. [0/90] Filament Orientation*

This study examines the effects of moisture and temperature on the flexural response of [0/90] Kevlar 49 fabric-reinforced epoxy laminates. Two high temperature (190°C) cure commercially available epoxies, Narmco 5208 and Ferro CE-9000, were used as matrix materials. Results indicate that the mechanical properties of Kevlar 49/epoxy laminates are temperature dependent over the range -55°C to 150°C. The addition of moisture magnifies temperature sensitivity. At 150°C and near saturation moisture content (5 weight percent), a strength loss of 60-70 percent and an effective stiffness loss of 40 percent from dry, room temperature values are measured. At 21°C, saturated specimens are found to be 35-40 per cent weaker than dry material. At low temperature (-55°C), strengths increase with the addition of moisture. Over the range of conditions tested, failure was not catastrophic, but was characterized by a loss in load carry ing capacity. Microscopic examination of failure modes indicates that flexural strength is determined by the ease with which filaments compres sively buckle. These results indicate that care must be taken when design ing with Kevlar-reinforced composites for use at elevated temperatures after exposure to moist environments. An accurate prediction of the ex pected composite moisture content and service temperature is important to the design process.

Effect of water hardness on the tolerance of the guppy to beryllium sulfate.

I t has been known for a number of years that various sal ts and metals are more toxic to aquatic organisms in sof t water than in hard water, due par t l y to the buffer ing capacity and calcium antagonism of hard water solut ions (see reviews by DOUDOROFF and KATZ 1950, 1953). Very l i t t l e data ex is t , however, regarding the t ox i c i t y of beryl l ium sal ts to aquatic organisms in spire of the wide indus t r ia l usage of beryl l ium (Be) for over 40 years.

Investigation of the protective properties and durability of enamel coatings under the influence of alternating loads

One of the m o r e topical aspects of the genera l problem of s t ruc tura l s trength of engineer ing m a t e r i a l s is to ensure the re l iab i l i ty of pa r t s exposed to the influence of act ive working media. Various methods are used to inc rease the l oad -ca r ry ing capacity of such par ts . Rather effect ive in this respec t is the application of enamel coatings which have the following useful p rope r t i e s [1-9]: f reedom from discont inui t ies through which meta l s could be attacked by aggress ive working media; high r e s i s t ance to the influence of aggress ive media; high heat res i s tance ; smooth and hard sur faces ; good adhesion to the metal substrate . In addition, enamel ing is a re la t ive ly s imple and inexpensive p rocess .

Daily changes in ventilatory capacity in smokers and in non-smokers.

The long-term effects of cigarette smoking on the respiratory tract have been studied by many authors by making a comparison between the incidence of clinical symptoms and signs of respiratory disease in smokers and that in non-smokers. The extensive literature on this subject was reviewed in the Report of the Royal College of Physicians on Smoking and (1962). Physiological evidence of the short-term effects of cigarette smoking shows that airway resistance, as judged by body plethysmograph records, is increased after the inhalation of cigarette smoke (Nadel and Comroe, 1961; Zamel, Youssef, and Prime, 1963). Physiological evidence of longer-term ventilatory defect attributable to cigarette smoking has been obtained by a comparison of ventilatory capacity in groups of smokers and non-smokers. Thus, Higgins (1959) found that indirect maximum breath ing capacity, based on measurements of three quarter second forced expiratory volume, was significantly lower in smokers than in non-smokers in random samples of men in England and Wales. Carey, Merrett, Elwood, Pemberton, and McAulay (1965) derived regression equations for the pre diction of one-second forced expiratory volume, FEV(l), and forced vital capacity, FVC, on age and stem height in non-byssinotic non-preparers in the flax-spinning industry; their findings were compatible with the hypothesis that, for a given age, sex, and stem height, and under similar conditions of exposure to occupational dust and similar resi dential exposure to air pollution, average values of FEV(l) are lower in smokers than in non-smokers. In what follows, an attempt has been made to compare daily changes in ventilatory capacity in a group of smokers with those in a group of non smokers, matched as closely as possible for relevant physical attributes as well as for occupation. Methods The subjects for the survey were selected from the sta f of Public Health Inspectors employed by the Belfast County Borough Health Committee. Out of a possible total of 52 men, 47 were seen at a preliminary interview when the age, stem height, and smoking habits of each man were recorded. As ventilatory capacity is known to be affected by age and by stem height (e.g. Carey and others, 1965), each smoker* was matched as closely as possible with a non-smoker with respect to age (?2 years) and stem heightt (?2 cm.). Seven smokers and seven non-smokers met these criteria for matching (Table I). The amounts smoked by the smokers had not varied greatly for at least the previous year, and no control had ever smoked in his life. A Poulton spirometer (McKerrow, McDermott, and Gilson, 1960) was used for the measurement in litres of forced expiratory volume?1 second, FEV(l), and forced vital capacity, FVC. The timing mechanism of the instrumert was calibrated, and the water temperature of the spirometer was taken before each series of tests. On each of the five days of the experiment, the water temperature of the spirometer was found to be within the range 15?-25? C, at which the accuracy of the instrument is better than ? 2 per cent., so that no further corrections were made to FEV(l) or FVC measure ments for temperature or barometric pressure changes. Each public health inspector participating in the study was instructed in the correct method of doing spirometry tests before the first day of the

Thin-Film Cryotrons: Part I-Properties of Thin Superconducting Films

This paper, consisting of three parts, describes the thin-film cryotron. This device, constructed by vacuum deposition of layers of lead, tin and silicon monoxide, is considerably smaller and faster than its wire-wound predecessor. Part I describes the characteristics of evaporated superconductive films as they apply to cryotrons. Their current-carrying capacity has been found to be proportional to width and proportional to thickness when the film is thinner than twice the penetration depth. Thermal effects caused by poor heat transfer to the bath distort the data, and the use of quartz substrates and low duty cycle pulse measurements help to reduce this distortion. The function of a superconductive reflector or ground plane under a film is discussed. The current-carry ing capacity of such a film is increased because of effective cancella tion of the normal component of magnetic field.

High-Altitude and Long-Distance Flights

THE Air Ministry has recently authorised the construction of two new experimental aeroplanes, one for high-altitude and the other for long-distance flights. The high-altitude machine will presumably be used for exploring the question of flight in the stratosphere, which is usually taken to mean that region in space above a height of 28,000 feet. There are plenty of aircraft in existence capable of reaching heights greater than this; the present record is 47,356 ft. held by the Italian pilot Donati, but no attempt has yet been made to deal with the possibilities of economical flight at such heights. The ultimate possibilities in this respect are much greater speeds owing to the reduced resistance of the rarified air. It will be necessary to carry superchargers to supply the required oxygen for the combustion of the engine fuel, appliances for breathing and heating, air-tight cabins or special suits for the occupants, and propellers the pitch of which can be changed to suit the different air conditions. These extras will have weight, which will reduce the fuel-carry ing capacity of the machine, and it is not impossible that this requirement alone will limit the practical utility of stratosphere flying.