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This paper describes an automatic adjustment system designed to measure and automatically minimize the difference in angular mismatch between the optical axes of a working (probe) beam and a marker beam that simulates the optical ...
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This paper describes an automatic adjustment system designed to measure and automatically minimize the difference in angular mismatch between the optical axes of a working (probe) beam and a marker beam that simulates the optical axis of the detector channel in a laser ranging system. This paper is primarily focused on the specifications of the basic components of the measurement system (laser sources, controllable optomechanical components, and sensors used to measure the angular orientation of the laser beams) used to maintain precision angular matching of the working and marker laser beams in order to develop a process for semi-natural simulation of a precision laser ranging system to produce and study angular matching between the working and marker beam axes. This seminatural simulation was used to model angular matching of the working and marker laser beams in a high-precision laser ranging system; the simulation was implemented using a laser system specifically developed for the purpose. The main results include a novel laser facility developed for semi-natural simulation of the angular matching of the probe (1064 nm) and marker (671 nm) beams in a laser ranging system where this difference in matching does not exceed 1". The facility periodically relays images of the laser beams to a polarization-based unit for matching of the beams using spatial filters. The facility was used to obtain experimental data on the positional characteristics of a quadrant photodiode and CMOS-array digital camera used as a laser beam matching unit.We show that this type of digital camera is preferred since it does not require advance knowledge of the positional characteristic. Initially aligned laser beamswere observed to randomly become misaligned due to angular instability in the laser beams.We have shown that the angular matching of the pulsed probe andCWmarker beams can be automatically controlled using a motorized mirror installed outside the marker-beam optical system and al
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Invasion of alien plant species is one of the main reasons for biodiversity loss in terrestrial ecosystems. However, alien plant species are not evenly distributed in the landscape. We studied which factors determine the actual le...
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Invasion of alien plant species is one of the main reasons for biodiversity loss in terrestrial ecosystems. However, alien plant species are not evenly distributed in the landscape. We studied which factors determine the actual level of neophyte invasion in a landscape with heterogeneous land-use and which habitats are the most infected. Since neophyte species with different life-forms can respond differently to the factors determining the invasion, species groups of annual, herbaceous perennial and woody neophytes were also analyzed separately.
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Traditional rural biotopes such as wood-pastures are species-rich environments that have been created by low-intensity agriculture. Their amount has decreased dramatically during the 20th century in whole Europe due to the intensi...
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Traditional rural biotopes such as wood-pastures are species-rich environments that have been created by low-intensity agriculture. Their amount has decreased dramatically during the 20th century in whole Europe due to the intensification of agriculture. Wood-pastures host some fungal species that prefer warm areas and are adapted to semi-open conditions, but still very little is known about fungi in these habitats. We studied how management, historical land-use intensity, present grazing intensity, time since abandonment, and stand conditions affect the species richness and community composition of ectomycorrhizal fungi. We surveyed fruit bodies on three 10?m?×?10?m study plots in 36 sites and repeated the surveys three times. Half of the sites were currently unmanaged but had a grazing history. We measured soil pH, soil moisture and the basal area of different tree species, and interviewed landowners about grazing history. We found that the proportion of broadleaved trees, soil pH, and soil moisture are the major drivers of the communities of ectomycorrhizal fungi in boreal wood-pastures. Management or grazing intensity did not have significant effects on fungal species richness, whereas historical land-use intensity seemed to have a negative effect on species richness. To conclude, present stand conditions are the most important factors to evaluate when planning the conservation of ectomycorrhizal fungi living in semi-open forest habitats.
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We introduce a new, cheap, fast and reliable method for marking slugs, using biologically inert UV-fluorescent dye. The dye remained visible for more than 3 months in all individuals marked. Use of the dye did not affect survival,...
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We introduce a new, cheap, fast and reliable method for marking slugs, using biologically inert UV-fluorescent dye. The dye remained visible for more than 3 months in all individuals marked. Use of the dye did not affect survival, spatial behaviour or daily activity of the slugs, nor the prey choice of the predatory beetle Pterostichus melanarius, under controlled semi-natural conditions. The new method will enable further investigations of absolute slug densities, diurnal activity, mobility and dispersal, using capture-recapture techniques. The resulting data would allow the construction of more exact forecasting models for the population dynamics of pest slugs, potentially leading to a reduction in the use of control agents, particularly chemical molluscicides.
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High Nature Value (HNV) farmland is typically characterised by low-intensity farming associated with high biodiversity and species of conservation concern. Mapping the occurrence and distribution of such farmland are useful for ap...
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High Nature Value (HNV) farmland is typically characterised by low-intensity farming associated with high biodiversity and species of conservation concern. Mapping the occurrence and distribution of such farmland are useful for appropriate targeting of conservation measures and supporting associated rural communities. We mapped the likely distribution of HNV farmland in the Republic of Ireland using a linear regression model incorporating established European indicators, adapted for Ireland and weightings based on expert opinion. The indicators used were semi-natural habitat cover, stocking density, hedgerow density, river and stream density and soil diversity, with highest weightings placed on the first two indicators (40% and 30%, respectively). The map provides information on the likely occurrence and distribution of HNV farmland in each electoral division as a reference point for future monitoring of the distribution of HNV farmland in the Republic of Ireland in order to assist with planning and policy development for the rural environment.
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Behaviors of sika deer in spring were studied by scan sampling, ad libitum sampling, and all-occurrence recording methods during 1998. The results showed that behaviors of sika deer in spring can be classified by seven categories:...
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Behaviors of sika deer in spring were studied by scan sampling, ad libitum sampling, and all-occurrence recording methods during 1998. The results showed that behaviors of sika deer in spring can be classified by seven categories: grazing, ruminating, bedding, moving, standing, drinking, alert, agonistic and other behaviors. Various behavioral models were more regular. Grazing behavior was a kind of mainly behavioral model.
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This document presents the International Committee for Coal and Organic Petrology (ICCP) classification of four organic components that cannot be included into any of the three maceral groups vitrinite, inertinite and liptinite: (...
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This document presents the International Committee for Coal and Organic Petrology (ICCP) classification of four organic components that cannot be included into any of the three maceral groups vitrinite, inertinite and liptinite: (1) Graphite; (2) Semi-graphite; (3) Natural coke; and (4) Natural char. Graphite and semi-graphite are related to high metamorphic grades and can be considered as end-members of the continuous coalification process of organic matter initially deposited as peat. Natural coke is formed from coal by a relatively local elevated heat flow caused by an intrusive body and it may thus occur in a range of coalification stages. Influence of heat from fire on coal or on gelified organic matter in peat forms natural char which therefore also occurs in a wide range of coalification stages.
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Semi-natural habitats are regularly shown to affect the diversity of predatory invertebrates at both local and landscape scales. In this study, we investigated the effects of three different vegetated field margins and the surroun...
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Semi-natural habitats are regularly shown to affect the diversity of predatory invertebrates at both local and landscape scales. In this study, we investigated the effects of three different vegetated field margins and the surrounding landscape composition on two common natural enemy taxa, carabids and spiders, in wheat fields of the North China Plain.
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Cryptographic algorithms are the basic of care-free transactions over the Internet today. Confidential information of a government or private agency or department is secured through the use of Cryptography. From doing secure commu...
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Cryptographic algorithms are the basic of care-free transactions over the Internet today. Confidential information of a government or private agency or department is secured through the use of Cryptography. From doing secure communication to transferring information of national importance, Cryptographic algorithms play the sole role in hiding the confidentiality. Musical attributes such as notes of which the music is composed are not constant and vary from composition to composition. Same tune played by different composers shows a variation in the sequence of notes used along with other attributes of a musical composition such as duration of each note and the frequency at which each note is played. Such a variation can be employed for the purpose of encrypting the message. In this paper, we have incorporated the use of Hindustani (North Indian) musical notes to encrypt messages. We have used a semi-natural composition process to generate note sequences of Indian music which can then be used as a tool for message hiding. This at first place ensures that the message is hidden from the intruder and second it gives a new random sequence of notes every time same message is sent. So the very purpose of a Cryptographic algorithm is served. The encrypted message in the form of musical notes is then sent to the intended recipient in the form of a musical composition which helps in defying the intruder of sensing any confidential information that is being sent over the communication channel.
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Twelve European habitat types were investigated to determine the influence of the IFBB technique (integrated generation of biogas and solid fuel from biomass) on the fate of organic compounds and energy yields of semi-natural gras...
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Twelve European habitat types were investigated to determine the influence of the IFBB technique (integrated generation of biogas and solid fuel from biomass) on the fate of organic compounds and energy yields of semi-natural grassland biomass. Concentration of organic compounds in silage and IFBB press cake (PC), mass flows within that system and methane yields of IFBB press fluids (PF) were determined. The gross energy yield of the IFBB technique was calculated in comparison to hay combustion (HC) and whole crop digestion (WCD). The IFBB treatment increased fibre and organic matter (OM) concentrations and lowered non-fibre carbohydrates and crude protein concentrations. The PF was highly digestible irrespective of habitat types, showing mean methane yields between 312.1 and 405.0 L_N CH_4 kg~(-1) VS. Gross energy yields for the IFBB system (9.75–30.19 MWh ha~(-1_) were in the range of HC, outperformed WCD and were influenced by the habitat type.
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