• Title/Summary/Keyword: Tropical conditions

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FLASH FLOOD FORECASTING USING REMOTELY SENSED INFORMATION AND NEURAL NETWORKS PART II : MODEL APPLICATION

  • Kim, Gwang-seob;Lee, Jong-Seok
    • Water Engineering Research
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    • v.3 no.2
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    • pp.123-134
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    • 2002
  • A developed Quantitative Flood Forecasting (QFF) model was applied to the mid-Atlantic region of the United States. The model incorporated the evolving structure and frequency of intense weather systems of the study area for improved flood forecasting. Besides using radiosonde and rainfall data, the model also used the satellite-derived characteristics of storm systems such as tropical cyclones, mesoscale convective complex systems and convective cloud clusters associated with synoptic atmospheric conditions as Input. Here, we present results from the application of the Quantitative Flood Forecasting (QFF) model in 2 small watersheds along the leeward side of the Appalachian Mountains in the mid-Atlantic region. Threat scores consistently above 0.6 and close to 0.8 ∼ 0.9 were obtained fur 18 hour lead-time forecasts, and skill scores of at least 40% and up to 55 % were obtained.

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Moisture distribution in concrete subjected to rain induced wetting-drying

  • Sarkar, Kaustav;Bhattacharjee, Bishwajit
    • Computers and Concrete
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    • v.14 no.6
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    • pp.635-656
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    • 2014
  • A rational estimation of moisture distribution in structural concrete is vital for predicting the possible extent and rate of progression of impending degradation processes. The paper proposes a numerical scheme for analysing the evolution of moisture distribution in concrete subjected to wetting-drying exposure caused by intermittent periods of rainfall. The proposed paradigm is based on the stage wise implementation of non-linear finite element (FE) analysis, with each stage representing a distinct phase of a typical wet-dry cycle. The associated boundary conditions have been constituted to realize the influence of various meteorological elements such as rain, wind, relative humidity and temperature on the exposed concrete surface. The reliability of the developed scheme has been demonstrated through its application for the simulation of experimentally recorded moisture profiles reported in published literature. A sensitivity analysis has also been carried out to study the influence of critical material properties on simulated results. The proposed scheme is vital to the service life modelling of concrete structures in tropical climates which largely remain exposed to the action of alternating rains.

Improved Single-Tone Frequency Estimation by Averaging and Weighted Linear Prediction

  • So, Hing Cheung;Liu, Hongqing
    • ETRI Journal
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    • v.33 no.1
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    • pp.27-31
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    • 2011
  • This paper addresses estimating the frequency of a cisoid in the presence of white Gaussian noise, which has numerous applications in communications, radar, sonar, and instrumentation and measurement. Due to the nonlinear nature of the frequency estimation problem, there is threshold effect, that is, large error estimates or outliers will occur at sufficiently low signal-to-noise ratio (SNR) conditions. Utilizing the ideas of averaging to increase SNR and weighted linear prediction, an optimal frequency estimator with smaller threshold SNR is developed. Computer simulations are included to compare its mean square error performance with that of the maximum likelihood (ML) estimator, improved weighted phase averager, generalized weighted linear predictor, and single weighted sample correlator as well as Cramer-Rao lower bound. In particular, with smaller computational requirement, the proposed estimator can achieve the same threshold and estimation performance of the ML method.

On the Cold Water Mass Around the Southeast Coast of Korean Peninsula

  • An, Hui Soo
    • 한국해양학회지
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    • v.9 no.2
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    • pp.10-18
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    • 1974
  • The cold water mass around the southeast coast of the Korean Peninsula is analyzed by using CSK data from 1966 through 1970. It is shown that this water mass flows down from the region offshore of Jukbyun to the area of Youngil Bay along the 100meter contour line of bottom topography. In ordinary summer conditions when the current velocity in the Korea Strait is usually above about 50cm/sec and the wind direction is southwest, the cold water ascends to the surface and makes the surface temperature gradient large, unless disturbed by a tropical cyclon. The bottom water of the Korea Strait is formed by the stratification after the Tsushima intermediate water and the Japan Sea intermediate water have been mixed. In winter the Tsushima intermediate water with high salinity sinks rapidly around the inlet of the Japan Sea and prevents the Japan Sea intemediate water from entering the Korea Strait.

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Evaluation and Selection of Potential Parents Based on Selection Indices and Isozyme Variability in Silkworm, Bombyx mori, L.

  • Moorthy S.M.;Das S.K.;Rao, P.R.T.;Urs S. Rao,;Sarkar A.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.14 no.1
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    • pp.1-7
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    • 2007
  • In order to find out the appropriate parents for the breeding programme, twelve bivoltine and three multivoltine silkworm breeds were evaluated on the basis of multivariate selection index and isozyme analysis. Of which, four [CSR2, D6 (P), SK3, SK4] bivoltine and two multivoltine (Nistari, Cambodge) breeds were selected and breeding initiated to develop higher survival bivoltine silkworm breed suitable for tropical conditions. Among two isozyme (Esterase and acid phosphatase) analyzed, only esterase exhibited polymorphism among the bivoltine breeds. No polymorphism was observed among multivoltine in respect of esterase as well as acid phosphatase.

House dust mite fauna in western Anatolia, Turkey

  • Ciftci Ihsan Hakki;Cetinkaya Zafer;Atambay Metin;Kiyildi Nilay;Aycan Ozlem M.;Daldal Nilgun
    • Parasites, Hosts and Diseases
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    • v.44 no.3
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    • pp.259-264
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    • 2006
  • House dust mites play an important role in the pathogenesis of allergic diseases. Many factors may influence mite growth. The presence of mites is related to mean temperature and humidity as well as altitude. The aim of this study was to analyze the mite fauna in 5 regions of western Anatolia, Turkey, that have similar climatic properties with low mean temperature and humidity, but differ in altitude. During the period October-November 2004, house dust was collected from 290 homes in 5 different cities. House dust mites were isolated in 67 (23.1 %) of 290 samples. The family Pyroglyphidae (Astigmata) was present in all positive samples. This study suggests that the selected western Anatolian regions that share similar environmental conditions host similar dust mite populations.

A GENERAL SIMULATION MODEL FOR CATTLE GROWTH AND BEEF PRODUCTION

  • Hirooka, H.;Yamada, Y.
    • Asian-Australasian Journal of Animal Sciences
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    • v.3 no.3
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    • pp.205-218
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    • 1990
  • A general model was developed to simulate cattle growth and beef production. The present model was constructed, based on ARC metabolizable energy system in principle, and incorporated up-to-date knowledge and information into previous models, which were reported by Sanders and Cartwright (1979a,b) and Kahn (1982). The model may apply to cover a wide range of genetic and environmental conditions, because many factors relating to cattle growth and beef production are taken into consideration. The model may provide better understanding of various components and processes of beef cattle production systems.

Prevalence of Dirofilaria immitis in Dogs in Shenyang, Northeastern China

  • Liu, Chengwu;Yang, Na;He, Jianbin;Yang, Min;Sun, Ming
    • Parasites, Hosts and Diseases
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    • v.51 no.3
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    • pp.375-377
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    • 2013
  • In the present study, we first report the seroprevalence of Dirofilaria immitis in dogs in Shenyang, northeastern China. Sera from 528 randomly selected dogs were examined for D. immitis antigen using SNAP$^{(R)}$4Dx test kit; 12.7% tested showed seropositive. No significant difference of infection was observed in different genders and breeds (P>0.05), but the difference was significant in different age groups and rearing conditions (P<0.05). The result suggested that the risk of exposure to D. immitis in dogs is high in Shenyang, and should be given attention.

Breeding of Bivoltine Silkworm Hybrids DP0308 and DP0314 in Sri Lanka : A Simplified but Practical Approach

  • Lea, Ho-Zoo
    • Journal of Sericultural and Entomological Science
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    • v.40 no.2
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    • pp.97-104
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    • 1998
  • Mainly due to limited genetic resources available and also urgent need for hybrids suitable to local conditions, conventional theories and regular methods for bivoltine silkworm breeding are not easily applicable in such a tropical country as Sri Lanka which is recently planning to scale-up the silk industry. A simplified but practical methodology was introduced to overcome such constraints. Through application of such modified informal breeding methods, two hybrids named DP0308 and DP0314 were selected for cocoon production. Details of the altered method of germplasm improvement in the silkworm are presented, along with combining ability and heritability estimates for six parental pure lines in a half-diallel cross.

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Assessing synoptic wind hazard in Australia utilising climate-simulated wind speeds

  • Sanabria, L.A.;Cechet, R.P.
    • Wind and Structures
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    • v.15 no.2
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    • pp.131-145
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    • 2012
  • Severe wind is one of the major natural hazards in Australia. The component contributors to economic loss in Australia with regards to severe wind are tropical cyclones, thunderstorms and subtropical (synoptic) storms. Geoscience Australia's Risk and Impact Analysis Group (RIAG) is developing mathematical models to study a number of natural hazards including wind hazard. This paper discusses wind hazard under current and future climate conditions using RIAG's synoptic wind hazard model. This model can be used in non-cyclonic regions of Australia (Region A in the Australian-New Zealand Wind Loading Standard; AS/NZS 1170.2:2011) where the wind hazard is dominated by synoptic and thunderstorm gust winds.