Miracle-dz/UniFAR-FTUs huggingface dataset:
Characterizing changes in cropping patterns using sequential Landsat imagery: an adaptive threshold approach and application to Phoenix, Arizona

Since the 1970s, the Phoenix Active Management Area has experienced rapid urbanization, mostly through land conversions from agricultural lands to urban land use. Rapid urban expansion and population growth have placed unprecedented pressure on agricultural production in this region. Agricultural intensification, in particular double cropping, has been observed globally as an important response to the growing pressure on land. However, the intensification has a number of negative impacts on water quality, biodiversity, and biogeochemical cycles. Thus, quantifying the spatial pattern of cropping intensity is important for natural resource management. In this study, we developed an adaptive threshold approach to map cropping intensity using time series Landsat data and examined the spatiotemporal patterns of cropping intensity in the Phoenix Active Management Area from 1995 to 2010 at 5-year intervals. To map cropping intensity accurately, the adaptive threshold algorithm was designed specifically to address several issues caused by the complex cropping patterns in the study area. The adaptive threshold method has abilities to (1) distinguish true crop cycles from multiple false phenological peaks, (2) minimize errors caused by data noise and missing data, (3) identify alfalfa and interyear crops and to distinguish alfalfa from double crops, and (4) adapt to temporal profiles with different numbers of observations. The adaptive threshold algorithm is effective in characterizing cropping intensity with overall accuracies exceeding 97%. Results show that there is a dramatic decline in the area of total croplands (46.1%), single crops (46.3%), and double crops (43.4%) during the study period. There was a small conversion (1.9%) from single to double crop from 1995 to 2000, whereas a reverse conversion (1.3%) was observed from 2005 to 2010. Updated and accurate information on the spatial distribution of cropping intensity provide important implications on effective and sustainable cropping practices. In addition, joint investigation on cropping patterns and irrigation water use can shed light on future agricultural water demand, which is of paramount importance in this rapidly expanding arid region.
Posición serial, densidad informativa y velocidad de lectura en el recuerdo de las cuñas de radio

One of the main goals of commercial communication is the recall of the product or service in an attempt to promote the purchase. The recall of a radio ad depends on several factors affecting its structural characteristics. At the macro level, because most of the radio commercials take the format of an ad, inserted into commercial breaks, it is important to determine if the degree of recall of the content is influenced by the position of the ad into the advertising break. But, furthermore, the degree of recall of an ad can be influenced by other microstructural elements, such as its density of information or its speech rate. Therefore, this study is to analyze if a serial position effect is found in the recall of radio commercials and if this can be influenced by other characteristics of the ad. The findings of the study suggest that it is not so important the position of the ad in the radio advertising break as their microstructural characteristics. When an advertisement presents low information density and effective formal elements, as well as improving the recall level, promotes the emergence of a serial position effect. Instead, this phenomenon does not occur when the microstructural conditions are not favorable.
Biogenic trace gases : measuring emissions from soil and water

List of Contributors. The Methods in Ecology Series. Preface. Trace Gas Exchange In An Ecosystem Context: Multiple Approaches For Measurement And Analysis. Enclosure-Based Measurement Of Trace Gas Exchange: Applications And Sources Of Error. Trace Gas Exchange Across The Air-Water Interface In Freshwater And Coastal Marine Environments. Trace Gas Exchange In Freshwater And Coastal Marine Environments: Ebullition And Transpost By Plants. Micrometeorological Techniques For Measuring Biosphere-Atmosphere Trace Gas Exchange. Standard Analytical Methods For Measuring Trace Gases In The Environment. Measurements Of Chemically Reactive Trace Gases At Ambient Concentrations. Recent Advances In Spectroscopic Instrumentation For Measuring Stable Gases In The Natural Environment. Use Of Isotopes And Tracers In The Study Of Emissions And Consumption Of Trace Gases In Terrestrial Environments. Microbial Processes Of Production And Consumption Of Nitric Oxide, Nitrous Oxide And Methane. Process Modelling And Spatial Extrapolation. Index.
Constraining the carbon tetrachloride (CCl4) budget using its global trend and inter‐hemispheric gradient

Carbon tetrachloride (CCl4) is a major anthropogenic ozone‐depleting substance and greenhouse gas and has been regulated under the Montreal Protocol. However, the near‐zero 2007–2012 emissions estimate based on the UNEP reported production and feedstock usage cannot be reconciled with the observed slow decline of atmospheric concentrations and the inter‐hemispheric gradient (IHG) for CCl4. Our 3‐D model simulations suggest that the observed IHG (1.5 ± 0.2 ppt for 2000–2012) is primarily caused by ongoing current emissions, while ocean and soil losses and stratosphere‐troposphere exchange together contribute a small negative gradient (~0 – −0.3 ppt). Using the observed CCl4 global trend and IHG, we deduce that the mean global emissions for the 2000–2012 period are 393445 Gg/yr (~30% of the peak 1980s emissions) and a corresponding total lifetime of 353732 years.
Comparison of Two Strength Criteria for Intact Rock

Two broadly based empirical strength criteria have recently been proposed for intact rock. The first, which applies to intact rock and rock masses was presented by Hoek and Brown in 1980. The second, which applies to all intact geomechanical materials ranging from slightly overconsolidated clays to hard rocks, was presented more recently by the writer. It is demonstrated that the two different criteria predict essentially the same variations in strength when each is applied to the material of common interest, namely relatively hard intact rocks.
TICFIRE: a far infrared payload to monitor the evolution of thin ice clouds

The TICFIRE mission concept developed with the support of the Canadian Space Agency aims: 1) to improve measurements of water-vapour concentration in the low limit, where cold regions are most sensitive and 2) to determine the contribution of Thin Ice Clouds (TIC) to the energy balance and the role of their microphysical properties on atmospheric cooling. TICFIRE is a process-oriented mission on a micro-satellite platform dedicated to observe key parameters of TIC forming in the cold regions of the Poles and globally, in the upper troposphere. It locates cloud top profiles at the limb and measures at nadir the corresponding upwelling radiance of the atmosphere directly in the thermal window and in the Far Infrared (FIR) spectrum over cold geographical regions, precisely where most of the atmospheric thermal cooling takes place. Due to technological limitations, the FIR spectrum (17 to 50 μm) is not regularly monitored by conventional sensors despite its major importance. This deficiency in key data also impacts operational weather forecasting. TICFIRE will provide on a global scale a needed contribution in calibrated radiance assimilation near the IR maximum emission to improve weather forecast. TICFIRE is therefore a science-driven mission with a strong operational component. The TICFIRE payload consists of two instruments; the main one being a Nadir-looking multiband radiometer based on uncooled microbolometer technology and covering a large spectral range from 7.9 μm to 50 μm. The secondary one is an imager that performs Limb measurements and provides cloud vertical structure information. This paper presents the key payload requirements, the conceptual design, and the estimated performance of the TICFIRE payload. Current technology developments in support to the mission are also presented.
Arctic polar stratospheric cloud observations by airborne lidar

Lidar observations obtained from January 24 to February 2, 1989, during the Airborne Arctic Stratospheric Expedition (AASE) mission further support the existence of two distinct classes (Types 1 and 2) of polar stratospheric clouds (PSCs). Most of the Type 1 PSCs observed were formed by rapid adiabatic cooling and exhibited very low depolarization ratios and low-to-intermediate scattering ratios. Type 2 PSCs were observed in regions of lowest temperature and showed much larger depolarization and scattering ratios, as would be expected from larger ice crystals. PSCs with low scattering ratios but moderate depolarization ratios were observed near the center of the vortex on one flight. These may have been either sparse Type 2 PSCs or Type 1 PSCs formed by less rapid cooling.
Hantaviruses: An Emerging Public Health threat in India?

The emerging viral diseases haemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS) are a cause of global concern as they are increasingly reported from newer regions of the world. The hantavirus species causing HFRS include Hantaan virus, Seoul virus, Puumala virus, and Dobrava-Belgrade virus while Sin Nombre virus was responsible for the 1993 outbreak of HCPS in the Four Corners Region of the US. Humans are accidental hosts and get infected by aerosols generated from contaminated urine, feces and saliva of infected rodents. Rodents are the natural hosts of these viruses and develop persistent infection. Human to human infections are rare and the evolution of the virus depends largely on that of the rodent host. The first hantavirus isolate to be cultured, Thottapalayam virus, is the only indigenous isolate from India, isolated from an insectivore in 1964 in Vellore, South India. Research on hantaviruses in India has been slow but steady since 2005. Serological investigation of patients with pyrexic illness revealed presence of anti-hantavirus IgM antibodies in 14.7% of them. The sero positivity of hantavirus infections in the general population is about 4% and people who live and work in close proximity with rodents have a greater risk of acquiring hantavirus infections. Molecular and serological evidence of hantavirus infections in rodents and man has also been documented in this country. The present review on hantaviruses is to increase awareness of these emerging pathogens and the threats they pose to the public health system. Keywords: Hantaviruses, Rodents
D″ beneath the Arctic from inversion of shear waveforms

The structure of the D″ region beneath the Arctic has not previously been studied in detail. Using waveform inversion, we find that the average S‐wave velocity in D″ beneath the Arctic is about 0.04 km/s higher than PREM, which is consistent with the existence of post‐perovskite (ppv) in D″. It is difficult to strongly constrain the fine structure of S‐velocity within D″ due to the small number of stations at epicentral distances Δ < 90°, but by weighting those stations heavily in the inversion, we show that the data suggest the existence of high S‐velocity in the upper half of D″ and low S‐velocity in the lower half, consistent with the possibility of a double crossing (ppv → pv reverse phase transition) within D″. We conduct a computational experiment to show that resolution of the velocity structure within D″ could be significantly improved by temporary installation of a portable array of seismographs in northern Canada, which would greatly increase the number of stations in the range 70° < Δ < 90°.
Drought Occurrence Probabilities and Risks of Dependent Hydrologic Processes

The occurrence probabilities, return periods, and risk of drought events are estimated for dependent hydrologic processes. Traditionally, Markovian models have been used for modeling hydrologic processes having short-term time dependence. However, they are inadequate for processes exhibiting longer time dependence. In this paper, low-order discrete autoregressive moving average (DARMA) models are used for modeling the variability of wet and dry years. Specifically, we center our attention on the occurrence of drought events, particularly their duration, by using the concept of runs. The probability distribution of drought occurrence, expected values and variances of first arrival and interarrival times of drought events, and the associated risks are derived. The derived equations and algorithms are verified by Monte Carlo simulation experiments. The applicability of the proposed methods is demonstrated by using annual streamflow data of the South Platte River in Colorado and the Niger River in Africa. It .
Physical Growth and Nutritional Status among Ao Naga Children of Nagaland, Northeast India

The present study was carried out on 571 Ao Naga children including 289 boys and 282 girls aged 8 to 15 years from Mokokchung town, Nagaland. This study tried to find out the physical growth according to the height and weight and nutritional status according to the body mass index (BMI) following the classification by Cole et al. Our study revealed that the girls were taller than boys till 13 years and the boys became taller thereafter. As for weight, the girls were heavier during 10 to 14 years. The mean height and weight increased as the age advanced in both boys and girls. The prevalence of underweight was 30.12% and the prevalence of overweight was 2.28% among the Ao Naga children, and the girls were found to have a higher prevalence of overweight and the boys had a higher prevalence of underweight. This revealed that both underweight and overweight coexisted among the Ao Naga children from Mokokchung town, although the prevalence of overweight was not high.
Recent Developments in Automatic Steering of Ships

This paper describes modern autopilots for ships. The development of modern optimal and adaptive control theories, together with the availability of inexpensive and fast digital computer systems, makes possible the design of more sophisticated controllers, which achieve better steering and save fuel. Autopilots which simultaneously control the yaw and roll motions are now being developed. In the near future it is to be expected that advanced track-prediction and track-keeping systems will facilitate the navigation and further contribute to fuel savings. The paper was presented at a Workshop held by the Netherlands branch of the Institute on 21 February 1986.
Steady Infiltration from a Shallow Circular Pond

Steady infiltration from a shallow, circular, inundated area on the horizontal surface of a semi-infinite porous medium is treated by a method of linearization proposed by J. R. Philip. Using this method, Philip retains most of the properties of the nonlinear system but reduces the differential equation to a linear type governing steady diffusion in a steady uniform flow. On the surface of the medium, the boundary conditions are of mixed type, although linear. These conditions are reduced to a system of dual integral equations solved by a modification of Tranter's method. Expressions for the distributions of vertical flux density, moisture content, and Stokes' stream function are derived, and numerical values of the last two quantities are illustrated graphically. It is found that the total flux depends almost linearly upon a parameter α, defined as the logarithmic derivative of the hydraulic conductivity with respect to capillary potential. Curves of mean flux over various radii (fractions of the total source radius) for various values of α indicate the importance of the guard ring in infiltrometer design.
The influence of surface and interstitial moisture on the spectral characteristics of intertidal sediments: Implications for airborne image acquisition and processing

Intertidal sediment distribution is an important factor in the understanding of estuarine ecological, morphological and pollution processes. Airborne remote sensing is identified as a cost-effective tool that may be used to provide accurate synoptic maps of estuarine sediment distributions. However, prior to the collection and analysis of airborne imagery, spectral characterization of intertidal sediments is fundamental. Through a series of in situ
Continuum percolation theory and Archie's law

Results for the unsaturated hydraulic conductivity, K, are adapted to generate the electrical conductivity, σ, as a function of moisture content, θ. The result for σ, evaluated θ = ϕ, (ϕ the porosity), yields σ ∝ ϕm, known as Archie's Law. This result is based on the fact that σ must vanish as the critical moisture content for percolation, θt, is approached, and on the apparent proportionality of θt to ϕ, at least in coarser porous media (with insignificant clay content). In three dimensions the power is expected to be 1.88, but in two dimensions, approximately 1.35. The former result is compatible with data summarized in Thompson et al., giving m = 1.86 ± 0.19, while the latter appears compatible with two‐dimensional simulations by Kuentz et al., who found m = 1.28 ± 0.07. The same analysis demonstrates that K cannot be written as a power of the porosity.
Canadian Ecotourists: Who are They?

Canadian ecotourists who travel in a group format are a distinct population of travellers. Their primary travel motives concentrate on the natural characteristics of the destination, with wilderness, parks and wildlife highly valued. In contrast, the average traveller travels for social purposes, with family, friends, safety and familiarity. The ecotourists show a high level of interest in their desired attractions, they want efficiency in their travel, meaning a desire to see as much as possible in the time available.These ecotourists tend to be older, more highly educated and have a much higher income than the average traveller. The ecotourists have high levels of travel expenditures with 48% spending inore than $4,000 a year. Demographic analysis suggests that in the future, as more people gain post-secondary education, the ecotourism market will expand accordingly.
Gondwanaland dispersion, Asian accretion and evolution of eastern Tethys∗

Most east and southeast Asian continental blocks, comprising North and South China, Indochina (including the Qamdo‐Simao Block), Tarim (including the Kunlun and Ala Shan Terranes), Qaidam, Sibumasu, Qiangtang, Lhasa, Kurosegawa, Northwest and Southeast Hainan, West Burma and Woyla Terranes, had their origins on the northern margin of Gondwanaland. Phanerozoic evolution of eastern Gondwanaland and Tethys involved the successive rifting and separation of three continental slivers (now recognised as collages of terranes) from northern Gondwanaland, their northwards drift, and amalgamation/accretion to form east and southeast Asia. These continental slivers separated from the margin of Gondwanaland in the Late Devonian (North China, South China, Indochina, Qaidam, Tarim and Hainan Island Terranes), Early‐mid‐Permian (the Cimmerian continent including the Sibumasu and Qiangtang Terranes), and Late Triassic‐Late Jurassic (Lhasa, West Burma and Woyla Terranes). The northwards drift of these terranes was accompan.
Development of the polar vortex in the 1999–2000 Arctic winter stratosphere

The 1999–2000 Arctic stratospheric vortex was unusually cold, especially in the early winter lower stratosphere, with a larger area near polar stratospheric cloud formation temperatures in Dec and Jan, and much lower temperatures averaged over Nov–Jan, than any previously observed Arctic winter. In Nov and early Dec, there was a double jet in the upper stratosphere, with the anticyclone cutoff in a region of cyclonic material. By late Dec, there was a discontinuous vortex, large in the upper stratosphere, small in the lower stratosphere; evolving to a strong, continuous, relatively upright vortex by mid‐Jan. This vortex evolution in 1999–2000 is typical of that in other cold early winters. Despite unusually low temperatures, the lower stratospheric vortex developed more slowly than in previous unusually cold early winters, and was weaker than average until late Dec.
Potential role of the quasi-biennial oscillation in the stratosphere-troposphere exchange as found in water vapor in general circulation model experiments

The tropical tropopause is considered to be the main region of upward transport of tropospheric air carrying water vapor and other tracers to the tropical stratosphere. The lower tropical stratosphere is also the region where the quasi-biennial oscillation (QBO) in the zonal wind is observed. The QBO is positioned in the region where the upward transport of tropospheric tracers to the overworld takes place. Hence the QBO can in principle modulate these transports by its secondary meridional circulation. This modulation is investigated in this study by an analysis of general circulation model (GCM) experiments with an assimilated QBO. The experiments show, first, that the temperature signal of the QBO modifies the specific humidity in the air transported upward and, second, that the secondary meridional circulation modulates the velocity of the upward transport. Thus during the eastward phase of the QBO the upward moving air is moister and the upward velocity is less than during the westward phase of the QBO. It was further found that the QBO period is too short to allow an equilibration of the moisture in the QBO region. This causes a QBO signal of the moisture which is considerably smaller than what could be obtained in the limiting case of indefinitely long QBO phases. This also allows a high sensitivity of the mean moisture over a QBO cycle to the El Nino-Southern Oscillation (ENSO) phenomena or major tropical volcanic eruptions. The interplay of sporadic volcanic eruptions, ENSO, and QBO can produce low-frequency variability in the water vapor content of the tropical stratosphere, which renders the isolation of the QBO signal in observational data of water vapor in the equatorial lower stratosphere difficult.
A 1000-year high precision record of δ 13 C in atmospheric CO 2

We present measurements of the stable carbon isotope ratio in air extracted from Antarctic ice core and firn samples. The same samples were previously used by Etheridge and co-workers to construct a high precision 1000-year record of atmospheric CO 2 concentration, featuring a close link between the ice and modern records and high-time resolution. Here, we start by confirming the trend in the Cape Grim in situ δ 13 C record from 1982 to 1996, and extend it back to 1978 using the Cape Grim Air Archive. The firn air δ 13 C agrees with the Cape Grim record, but only after correction for gravitational separation at depth, for diffusion effects associated with disequilibrium between the atmosphere and firm, and allowance for a latidudinal gradient in δ 13 C between Cape Grim and the Antarctic coast. Complex calibration strategies are required to cope with several additional systematic influences on the ice core δ 13 C record. Errors are assigned to each ice core value to reflect statistical and systematic biases (between ± 0.025‰ and ± 0.07‰); uncertainties (of up to ± 0.05‰) between core-versus-core, ice-versus-firn and firn-versus-troposphere are described separately. An almost continuous atmospheric history of δ 13 C over 1000 years results, exhibiting significant decadal-to-century scale variability unlike that from earlier proxy records. The decrease in δ 13 C from 1860 to 1960 involves a series of steps confirming enhanced sensitivity of δ 13 C to decadal timescale-forcing, compared to the CO 2 record. Synchronous with a ‘‘Little Ice Age’′ CO 2 decrease, an enhancement of δ 13 C implies a terrestrial response to cooler temperatures. Between 1200 AD and 1600 AD, the atmospheric δ 13 C appear stable. DOI: 10.1034/j.1600-0889.1999. t01-1-00005.x