344 research outputs found
RRS Discovery Cruise 243, 11th October to 22nd November 1999. Sensory Biology in the Deep-Sea: Anatomy, Physiology, and Molecular Biology
RRS Discovery cruise 243 had two principal objectives: to collect deep-sea animals for a variety of biological studies ranging from physiology to molecular biology, and to deploy benthic landers. The landers are described in Section 9.1, and the midwater and benthic trawling in Section 9.2. A complete list of the stations worked, with times, latitudes and longitudes, is given in Section 10, and a track chart for the whole cruise is shown in Section 11.
Trawling was conducted first and foremost in order to provide specimens required for work associated with NERC grant GR3/B1212 âAnalysis of light-induced interactions in the deep-sea: bioluminescence and its relation to vision, reflectance and fluorescenceâ to Professor Peter Herring, Dr Julian Partridge, and Dr Peter Shelton. Of equal importance to the success of the cruise, however, was the provision of biological samples for a range of inter-related studies. Descriptions of these studies are given in Section 9.3.
Throughout the cruise a narrative (Section 6) was compiled to document, in diary format, the main scientific activities on board ship. It also records information about factors which affected work, such as the weather, and problems with equipment. The narrative is more or less a list of notes rather than proper prose, and was written during the cruise, documenting events as they were planned, as they unfolded, or after they had happened. In consequence, the tenses of verbs tend to vary in a haphazard way, for which I apologise.
During the cruise, the Discovery âRough Logâ of biological specimens was maintained by Professor Peter Herring. A prĂ©cis of some of the information from the Rough Log is incorporated into the narrative as a record of some of the most common, and some of the most unusual, animals that were collected. This is necessarily a biased record. Nevertheless, it may be useful to others planning or conducting similar cruises to the areas worked during D243, particularly those targeting the pelagic macrofauna.
As the narrative shows, D243 was plagued by problems with the main winch. At one stage, early in the cruise, the severity of these problems made it likely that the cruise would have to be terminated prematurely, without any trawling having been undertaken. That this situation was reversed is due to the determination and hard work of the RVS technicians who were on board the ship. To them, Phil Taylor (RVS Technical Liaison Officer/TLO), Kevin Smith (RVS Mobilisation Officer/MO), Paul Duncan, and Rhys Roberts, we are much indebted: without their labours the cruise would not have succeeded in the way it ultimately did.
Inevitably, the âscience timeâ of the cruise was affected by the winch problems (see Section 8) and was contributory to a decision not to work the slope of the African continent, which had been part of the original cruise directive. This was, however, to some extent compensated by the generally stable weather conditions in the work area. Although we encountered conditions more extreme than are indicated in the âAfrica Pilotâ for the region during October/November (anticipated average wind force 3), at no time was work stopped by poor weather. This in itself partly justifies the relatively long passage time to the work area. The main reason for working in the region, however, was the high diversity and abundance of midwater and benthic macrofauna in this region of upwelling and high surface water productivity. This, in combination with the trawling methods used, which included the use of the relatively large RMT25 net and a closing cod end on the RMT8 net, ensured that the requirements of the scientific personnel for specimens were well met.
The scientific complement of the cruise consisted of 23 people, ranging from graduate students to professors, from five countries and eleven institutions. In addition, the cruise also hosted a team from the BBC Natural History Unit, who were on board to film for the âThe Blue Planetâ, a television series about the seas which is due for release in 2001. That this diverse group (who are listed, with their contact details, in Section 2) worked so well together, and were steadfastly cheerful firstly in the face of the winch problems, and later in the face of the relentlessness of trawling and catch processing, is very much to their credit. As Principal Scientist on D243 I am extremely grateful for their hard work and support in the run-up to the cruise, during the time at sea, and in its aftermath. In particular I would like to single out for thanks Ben Boorman and Nigel Merrett who, as scientific day and night watch
leaders, ensured that the fishing and the supply of specimens continued without a break.
D243 was also notable for one other event: it was Peter Herringâ last cruise before his retirement from the Southampton Oceanography Centre. Without a doubt, none of the participants on D243 would have been there but for Peter, such has been his impact on ocean going biology. Indeed, the format of D243 very much follows the successful formula developed by him on numerous previous cruises, including some to the Cape Verde region of the West African upwelling. If a cruise report can be dedicated, this is dedicated to him
Transformers:Intrusion Detection Data In Disguise
IoT cyber security deficiencies are an increasing concern for users, operators, and developers. With no immediate and holistic devicelevel fixes in sight, alternative wraparound defensive measures are required. Intrusion Detection Systems (IDS) present one such option, and represent an active field of research within the IoT space. IoT environments offer rich contextual and situational information from their interaction with the physical processes they control, which may be of use to such IDS. This paper uses a comprehensive analysis of the current stateof-the-art in context and situationally aware IoT IDS to define the often misunderstood concepts of context and situational awareness in relation to their use within IoT IDS. Building on this, a unified approach to transforming and exploiting such a rich additional data set is proposed to enhance the efficacy of current IDS approaches
ICS Testbed Tetris:Practical Building Blocks Towards a Cyber Security Resource
Cyber attacks on Critical National Infrastructure (CNI) can be hugely detrimental to society, notably via compromising Industrial Control Systems (ICS) that underpin core CNI functions. In order to explore in-depth ICS Cyber Security challenges, testbeds are an essential tool, avoiding the need to experiment exclusively on live systems. However, ICS testbed creation is a complex multidisciplinary challenge, with a plethora of conflicting requirements. This paper, based on over six years of ICS testbed research and development that spans multiple diverse applications, proposes a flexible high-level model that can be adopted to support ICS testbed development. This is complemented by a baseline set of practical implementation guidance incorporating related and emerging technologies. As a collective, the model and implementation guidance offers a go-to guide for a wide range of end-users. Furthermore, it provides a coherent foundational structure towards establishing an online "living" resource, which can be expanded over time through broader community engagement
COSMOS-Europe: a European network of cosmic-ray neutron soil moisture sensors
[EN] Climate change increases the occurrence and severity of droughts due to increasing temperatures, altered circulation patterns, and reduced snow occurrence. While Europe has suffered from drought events in the last decade unlike ever seen since the beginning of weather recordings, harmonized long-term datasets across the continent are needed to monitor change and support predictions. Here we present soil moisture data from 66 cosmic-ray neutron sensors (CRNSs) in Europe (COSMOS-Europe for short) covering recent drought events. The CRNS sites are distributed across Europe and cover all major land use types and climate zones in Europe. The raw neutron count data from the CRNS stations were provided by 24 research institutions and processed using state-of-the-art methods. The harmonized processing included correction of the raw neutron counts and a harmonized methodology for the conversion into soil moisture based on available in situ information. In addition, the uncertainty estimate is provided with the dataset, information that is particularly useful for remote sensing and modeling applications. This paper presents the current spatiotemporal coverage of CRNS stations in Europe and describes the protocols for data processing from raw measurements to consistent soil moisture products. The data of the presented COSMOS-Europe network open up a manifold of potential applications for environmental research, such as remote sensing data validation, trend analysis, or model assimilation The dataset could be of particular importance for the analysis of extreme climatic events at the continental scale. Due its timely relevance in the scope of climate change in the recent years, we demonstrate this potential application with a brief analysis on the spatiotemporal soil moisture variability. The dataset, entitled "Dataset of COSMOS-Europe: A European network of Cosmic-Ray Neutron Soil Moisture Sensors", is shared via Forschungszentrum Julich: https://doi.org/10.34731/x9s3-kr48 (Bogena and Ney, 2021).We thank TERENO (Terrestrial Environmental Observatories), funded by the Helmholtz-Gemeinschaft for the financing and maintenance of CRNS stations. We acknowledge financial support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) of the research unit FOR 2694 Cosmic Sense (grant no. 357874777) and by the German Federal Ministry of Education of the Research BiookonomieREVIER, Digitales Geosystem -Rheinisches Revier project (grant no. 031B0918A). COSMOS-UK has been supported financially by the UK's Natural Environment Research Council (grant no. NE/R016429/1). The Olocau experimental watershed is partially supported by the Spanish Ministry of Science and Innovation through the research project TETISCHANGE (grant no. RTI2018-093717-BI00). The Calderona experimental site is partially supported by the Spanish Ministry of Science and Innovation through the research projects CEHYRFO-MED (grant no. CGL2017-86839C3-2-R) and SILVADAPT.NET (grant no. RED2018-102719-T) and the LIFE project RESILIENT FORESTS (grant no. LIFE17 CCA/ES/000063). The University of Bristol's Sheepdrove sites have been supported by the UK's Natural Environment Research Council through a number of projects (grant nos. NE/M003086/1, NE/R004897/1, and NE/T005645/1) and by the International Atomic Energy Agency of the United Nations (grant no. CRP D12014).Bogena, HR.; Schrön, M.; Jakobi, J.; Ney, P.; Zacharias, S.; Andreasen, M.; Baatz, R.... (2022). COSMOS-Europe: a European network of cosmic-ray neutron soil moisture sensors. Earth System Science Data. 14(3):1125-1151. https://doi.org/10.5194/essd-14-1125-20221125115114
Testing for Fictive Learning in Decision-Making Under Uncertainty
We conduct two experiments where subjects make a sequence of binary choices between risky and ambiguous binary lotteries. Risky lotteries are deïŹned as lotteries where the relative frequencies of outcomes are known. Ambiguous lotteries are lotteries where the relative frequencies of outcomes are not known or may not exist. The trials in each experiment are divided into three phases: pre-treatment, treatment and post-treatment. The trials in the pre-treatment and post-treatment phases are the same. As such, the trials before and after the treatment phase are dependent, clustered matched-pairs, that we analyze with the alternating logistic regression (ALR) package in SAS. In both experiments, we reveal to each subject the outcomes of her actual and counterfactual choices in the treatment phase. The treatments diïŹer in the complexity of the random process used to generate the relative frequencies of the payoïŹs of the ambiguous lotteries. In the ïŹrst experiment, the probabilities can be inferred from the converging sample averages of the observed actual and counterfactual outcomes of the ambiguous lotteries. In the second experiment the sample averages do not converge. If we deïŹne ïŹctive learning in an experiment as statistically signiïŹcant changes in the responses of subjects before and after the treatment phase of an experiment, then we expect ïŹctive learning in the ïŹrst experiment, but no ïŹctive learning in the second experiment. The surprising ïŹnding in this paper is the presence of ïŹctive learning in the second experiment. We attribute this counterintuitive result to apophenia: âseeing meaningful patterns in meaningless or random data.â A reïŹnement of this result is the inference from a subsequent Chi-squared test, that the eïŹects of ïŹctive learning in the ïŹrst experiment are signiïŹcantly diïŹerent from the eïŹects of ïŹctive learning in the second experiment
Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV
The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of âs = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pTâ„20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60â€pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2â€{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
The chi_b(nP) quarkonium states are produced in proton-proton collisions at
the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS
detector. Using a data sample corresponding to an integrated luminosity of 4.4
fb^-1, these states are reconstructed through their radiative decays to
Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks
corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new
structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is
also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes.
This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table,
corrected author list, matches final version in Physical Review Letter
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