bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigating Factors Influencing the Quality of Crowdsourced Work Under Different Incentives
Authors: Mourelatos Evangelos , Tzagarakis Manolis
Published: April 2019

Crowdsourcing is a new form of online labor, where the process of solving a problem is approached by soliciting contributions from a large group of people. In this paper, the authors attempt to investigate how different incentives affect the quality of work in such contexts, by completing the same task in three different environments: in a laboratory setting, on a social networking as well as on a crowdsourcing site. Analyzing the obtained results indicates that under different incentives, different factors contribute to the quality of work in crowdsourcing tasks. In general the research highlights that the identification of factors contributing positively to higher quality of work in crowdsourcing environments is a complex question, depending on the task at hand.
“Do-It-Yourself Justice”
Authors: Rizza Caroline , Pereira Ângela Guimarães , Curvelo Paula
Published: April 2019

In June 2011, during the ice hockey Stanley Cup, as the Vancouver Canucks were losing, riots started in downtown Vancouver. Social media were used to communicate between authorities and citizens, including the rioters. The media reporting on these events framed these communications within different narratives, which in turn raised ethical considerations. The authors identify and reflect upon ideas of justice, fairness, responsibility, accountability and integrity that arise in the media stories. In addition they investigate (1) the “institutional unpreparedness” of the Vancouver police department when receiving such quantity of material and dealing with new processes of inquiry such material requires; (2) the “unintended do-it-yourself-justice”: the shift from supporting crisis responders to social media vigilantes: citizens overruling authorities and enforcing justice on their own terms and by their own means through social media and; (3) the “unintended do-it-yourself-society” supported by the potential-of social media's use for prompting people to act.
Shared Practices in Articulating and Sharing Rationale
Authors: Xiao Lu , Carroll John M.
Published: April 2019

This paper reports a classroom study in which group learners brainstormed ideas in virtual group space and justified their ideas through articulating their rationales in the shared rationale space. The investigation focused on the learners' practices of articulating and sharing rationales. The results suggest that group members would brainstorm the ideas and generate rationales to justify the ideas before reading the others' ideas and rationales. Also, the members in general brainstormed all the ideas first and then elaborated the rationales to justify the ideas; and grouped the shared rationales according to their authors. The group members' reasoning styles were examined by using Rhetorical Structure Theory to analyze the shared rationales. It was found that similar reasoning styles existed across the groups. Additionally, the group context seemed to have affected the members' strategies of using contextual and additional information to justify their ideas. Several design implications are presented to support the practices of articulating and sharing rationales in virtual group workspace. The authors also articulate how their work contributes to other research areas such as project management, crowdsourcing, and online deliberation. Based on their study, the authors argue for a rationale-based knowledge management approach to complex collective activities in the online environment.
The Role of Affective Computing for Improving Situation Awareness in Unmanned Aerial Vehicle Operations
Authors: Bishop Jonathan
Published: April 2019

Unmanned aerial vehicles (UAVs), commonly known as drones, are a robotic form of military aircraft that are remotely operated by humans. Due to lack of situation awareness, such technology has led to the deaths of civilians through the inaccurate targeting of missile or gun attacks. This chapter presents the case for how a patented invention can be used to reduce civilian casualties through attaching an affect recognition sensor to a UAV that uses a database of strategies, tactics and commands to better instruct fighter pilots on how to respond while in combat so as to avoid misinterpreting civilians as combatants. The chapter discusses how this system, called VoisJet, can reduce many of the difficulties that come about for UAV pilots, including reducing cognitive load and opportunity for missing data. The chapter concludes that using UAVs fitted with VoisJet could allow for the reduction of the size of standing armies so that defence budgets are not overstretched outside of peacetime.
A Centralized Autonomous System of Cooperation for UAVs- Monitoring and USVs- Cleaning
Authors: Bella Salima , Belbachir Assia , Belalem Ghalem
Published: April 2019

This article proposes an approach which deals with the problem of monitoring ocean pollution and cleaning dirty zones using autonomous unmanned vehicles. The authors present a cooperative agent-based planning approach for heterogeneous unmanned vehicles with different roles. Unmanned aerial vehicles (UAVs) monitor multiple ocean regions and unmanned surface vehicles (USVs) tackle the cleaning of dirty zones. Due to the rapid deployment of these unmanned vehicles, and the increase of ocean pollution, it is convenient to use a fleet of unmanned vehicles. Thus, most of the existing studies deal with the monitoring of different zones, the detection of the polluted zones and then the cleaning of the zones. In order to optimize this process, the authors' solution aims to use one UAV and one USV to reduce the pollution level of the ocean zones while taking into account the problem of fault tolerance related to these vehicles.
The “Outgoing Strategy” of Chinese Companies
Authors: Zhou Ping , Wong Tim
Published: April 2019

The globalization of economics and China's accession to the World Trade Organization (WTO) have brought new opportunities and challenges to Chinese enterprises. Taking the sense of globalization, China is participating in global resource allocation, expanding and utilizing the market on the global scale, actively participating in international division and cooperation, and implementing international operation are important steps for Chinese enterprises to go abroad and seize the initiative in the global economic competition. In China, the strategy of “going out” is still at the initial stage. Compared with the developed countries, there is still a large gap between China and other developed countries in terms of investment amount, enterprise scale, and internationalization. China enterprises can adapt to the changing environment of international market; the key is to improve the competitiveness of enterprises in the international market, which is a crucial step in expanding Chinese enterprises' international market.
Research on Protection and Development of Intellectual Property in China From the Perspective of “The Belt and Road”
Authors: Zhou Ping , Li Fuda , Zhong Linling
Published: April 2019

With the continuous upgrading of the economical industry structure and the gradual optimization of the excess capacity, China has begun to get rid of the name “world factory” of “processing with imported materials.” However, there are problems still existing, such as the contradiction between enterprises' poor independent innovation ability and consumers' increasing demands on product quality. Enterprises in China have the great opportunity to “go out” because of “The Belt and Road” strategy, but it is extremely complicated in legal system, customs, and social culture, which means how to use of intellectual property in China coexists risks and opportunities for enterprises. This chapter focuses on analyzing problems of intellectual property rights in China and the importance of the protection and development of intellectual property. In addition, this chapter studies strategies that can be provided for the protection and development of intellectual property in China from the perspective of “The Belt and Road.”
Investigation on Varying Aluminum Doping Concentrations and Sintering Temperatures on the Synthesis of Garnet Li7La3Zr2O12 solid Electrolyte via Modified Pechini Method
Authors: Alfaro Benjamin Jose , Cervera Rinlee Butch M.
Published: April 2019

Solid electrolytes such as lithium lanthanum zirconate have shown a lot of promise in an all-solid-state Lithium-based battery since the discovery of its highly conductive cubic garnet structure. In this study, different concentrations of Al-doped Lithium Lanthanum Zirconate (Al-doped LLZ) having the formula of Li7-.3xAlxLa3Zr2O12 with x = 0.1,0 .2, 0.3, were synthesized via modified Pechini method and the effect of sintering temperatures, 1150 and 1200 °C, on the resulting properties were investigated. X-ray diffraction results have shown that cubic Al-doped LLZ can be obtained at a lower temperature using Pechini method. Significant effect to the conductivity on the different sintering temperatures was observed for the 0.1 Al-doped LLZ. With the different studied compositions synthesized via modified Pechini method, it was revealed that the 0.2 Al doped LLZ sintered either at 1150 or 1200 °C showed the highest conductivity of about 1.4x10-4 S/cm.
Material of High Temperature Heat Exchanger in Fuel Cell System
Authors: Zhang Zhao Huan , Ba Li Ming , Li Chu Fu , Li Xuan , Guo Qiang
Published: April 2019

Solid Oxide Fuel Cell (SOFC) systems are considered to be the most competitive green energy technology in the future because of their high energy conversion rates, low emissions and multiple fuels available. High temperature heat exchanger plays an important role in the system. The process system requires the design of heat exchangers to achieve operating temperature (700-800 °C), cross-temperature (>500°C) and low pressure drop in the smallest space, which is a challenge to the choice of materials. In this paper, the performances (Tensile strength, yield strength, linear expansion coefficient, and thermal conductivity coefficient) and price of high temperature alloy materials (304H, 310S, incoloy800H and Incoloy625) in the current application environment are compared. The applicable material (310S) of heat exchanger is determined. It provides a material basis for research and development of high temperature heat exchangers in SOFC system and commercialization.
Synthesis and Functionalization of Filamentous Carbon Material via Decomposition of 1,2-Dichlorethane over Self-Organizing Ni-Mo Catalyst
Authors: Bauman Yurii , Kibis Lidiya , Mishakov Ilya , Rudneva Yuliya , Stoyanovskii Vladimir O. , Vedyagin Aleksey A.
Published: April 2019

Segmented carbon filaments produced by catalytic decomposition of 1,2-dichloroethane over Ni-Mo (8 wt.% Mo) self-organizing catalyst were subjected to functionalization in two different regimes. The structure, textural properties and chemical composition of surface were studied using SEM, Raman spectroscopy, adsorption (BET) and XPS. It was shown that oxidation of carbon nanomaterial in concentrated HNO3 results in enhancement of O-containing groups concentration (from 2.2 to 6.8 wt.%), increase in specific surface area (from 224 to 280 m2/g) and slight structural disorder of graphitic material (increase of ID/IG ratio from 2.15 to 1.84).
Analysis of the Cutting Surface Striation Shape
Authors: Li Liu Can , Xu Qi Wen , Guo Chu Wen
Published: April 2019

In the process of abrasive water jet (AWJ) cutting, there will produce a series of striation shape on the cutting surface of target. In this paper, we define such striation as cutting striation shape. The most research of this paper is the force situation and movement trajectory of water jet in the process of cutting. It is deduced by theory that the cutting surface striation shape is circular arc and find that the radius of circular arc is related to cutting velocity, cutting pressure and the property of cutting material. In the experiment, stainless steel 304 and aluminum 6061 were cut by AWJ and the result shows that the shape of the surface striation is arc-shaped in both material surface. At different cutting pressure, for a same material, K_R is a constant value which is only related to the property of cutting material.
Forming Analysis of AZ80 Magnesium Alloy Thick-Walled Tube Fabricated by Hydrostatic Shrinkage Extrusion
Authors: Li Yang , Yuan Ren Shu
Published: April 2019

In order to obtain high performance magnesium alloy thick-walled tubes, the magnesium alloy ingot was extruded by hydrostatic shrinkage extrusion technology. Through a series of experiments, it was found that the magnesium alloy tube was not formed in the extrusion ratio that is smaller than 2.11 . Deform-3D software was used to simulate the tube forming process under different extrusion ratios. It was noting that at the condition of the extrusion ratio of 2.11, the equivalent stress and strain of the extruded tube at the fixed sizing zone were obviously unevenly distributed, which was disappeared with the increase of the extrusion ratio. Compared with the homogenized magnesium alloy , the yield strength, the tensile strength and the elongation were improved when the tensile test was carried out on the extruded magnesium alloy thick-walled tube. These results clearly showed that the mechanical properties of magnesium alloy tubes were improved after hydrostatic extrusion.
Systemic Antibiotic Therapy Reduces Circulating Inflammatory Dendritic Cells and Treg–Th17 Plasticity in Periodontitis
Authors: Rajendran Mythilypriya , Looney Stephen , Singh Nagendra , Elashiry Mahmoud , Meghil Mohamed M. , El-Awady Ahmed R. , Tawfik Omnia , Susin Cristiano , Arce Roger M. , Cutler Christopher W.
Published: April 2019

Periodontitis (PD) is a common dysbiotic inflammatory disease that leads to local bone deterioration and tooth loss. PD patients experience low-grade bacteremias with oral microbes implicated in the risk of heart disease, cancer, and kidney failure. Although Th17 effectors are vital to fighting infection, functional imbalance of Th17 effectors and regulatory T cells (Tregs) promote inflammatory diseases. In this study, we investigated, in a small pilot randomized clinical trial, whether expansion of inflammatory blood myeloid dendritic cells (DCs) and conversion of Tregs to Th17 cells could be modulated with antibiotics (AB) as part of initial therapy in PD patients. PD patients were randomly assigned to either 7 d of peroral metronidazole/amoxicillin AB treatment or no AB, along with standard care debridement and chlorhexidine mouthwash. 16s ribosomal RNA analysis of keystone pathogen Porphyromonas gingivalis and its consortium members Fusobacterium nucleatum and Streptococcus gordonii confirmed the presence of all three species in the reservoirs (subgingival pockets and blood DCs) of PD patients before treatment. Of the three species, P. gingivalis was reduced in both reservoirs 4–6 wk after therapy. Further, the frequency of CD1C+CCR6+ myeloid DCs and IL-1R1 expression on IL-17A+FOXP3+CD4+ T cells in PD patients were reduced to healthy control levels. The latter led to decreased IL-1β–stimulated Treg plasticity in PD patients and improvement in clinical measures of PD. Overall, we identified an important, albeit short-term, beneficial role of AB therapy in reducing inflammatory DCs and Treg–Th17 plasticity in humans with PD.
Outcomes of colpectomy for uterovaginal and posthysterectomy vault prolapse: A comparative study between normal and overweight women
Authors: Hengrasmee Pattaya , Wachasiddhisilpa Parit , Asumpinwong Chutimon , Leerasiri Pichai
Published: April 2019

The objective of the study is to compare success and perioperative outcomes of colpectomy for severe prolapse between normal and overweight patients. This is a retrospective cohort study of 95 non-sexually active women undergoing colpectomy for severe prolapse between July 2010 and December 2015. Vaginal hysterectomy was performed for those with uterovaginal prolapse. Prolapse stage and location were identified according to Pelvic Organ Prolapse Quantification (POP-Q) measurements. Demographic data and perioperative outcomes were recorded. Patients were categorized into normal-weight and overweight groups according to World Health Organization body mass index classification for adults. During postoperative visit, prolapse symptoms and POP-Q measurements were re-evaluated. Objective cure was defined as prolapse at or above hymen, while subjective cure determined as resolution of prolapse sensation. One-third was determined as overweight. Objective cure was 81.1%, whereas subjective cure was 95.8%. Overweight patients significantly demonstrated poorer perioperative outcomes including increased blood loss, more advanced stage prolapse, and lower success rates. In conclusion, colpectomy is an effective repair procedure for non-sexually active women with severe prolapse due to low perioperative morbidities and favorable surgical outcomes. However, special precaution is required when performing this procedure in overweight women.
Existence ofixed points for pointwise eventually asymptotically nonexpansive mappings
Authors: Radhakrishnan M. , Rajesh S.
Published: April 2019

Kirk introduced the notion of pointwise eventually asymptotically non-expansive mappings and proved that uniformly convex Banach spaces have the fixed point property for pointwise eventually asymptotically non expansive maps. Further, Kirk raised the following question: “Does a Banach space X have the fixed point property for pointwise eventually asymptotically nonexpansive mappings when ever X has the fixed point property for nonexpansive mappings?”. In this paper, we prove that a Banach space X has the fixed point property for pointwise eventually asymptotically nonexpansive maps if X  has uniform normal structure or X is uniformly convex in every direction with the Maluta constant D(X) < 1. Also, we study the asymptotic behavior of the sequence {Tnx} for a pointwise eventually asymptotically nonexpansive map T defined on a nonempty weakly compact convex subset K of a Banach space X whenever X satisfies the uniform Opial condition or X has a weakly continuous duality map.
When is X × Y homeomorphic to X ×l Y?
Authors: Buzyakova Raushan
Published: April 2019

We identify a class of linearly ordered topological spaces X that may satisfy the property that X × X is homeomorphic to X ×l X or can be embedded into a linearly ordered space with the stated property. We justify the conjectures by partial results.
Indications for a potential synchronization between the phase evolution of the Madden–Julian oscillation and the solar 27-day cycle
Authors: Hoffmann Christoph G. , von Savigny Christian
Published: April 2019

Abstract. The Madden–Julian oscillation (MJO) is a major source of
intraseasonal variability in the troposphere. Recently, studies have
indicated that also the solar 27-day variability could cause variability in
the troposphere. Furthermore, it has been indicated that both sources could
be linked, and particularly that the occurrence of strong MJO events could be
modulated by the solar 27-day cycle. In this paper, we analyze whether the temporal evolution of the MJO phases
could also be linked to the solar 27-day cycle. We basically count the
occurrences of particular MJO phases as a function of time lag after the
solar 27-day extrema in about 38 years of MJO data. Furthermore, we develop a
quantification approach to measure the strength of such a possible
relationship and use this to compare the behavior for different atmospheric
conditions and different datasets, among others. The significance of the
results is estimated based on different variants of the Monte Carlo approach,
which are also compared. We find indications for a synchronization between the MJO phase evolution and
the solar 27-day cycle, which are most notable under certain conditions: MJO
events with a strength greater than 0.5, during the easterly phase of the
quasi-biennial oscillation, and during boreal winter. The MJO appears to
cycle through its eight phases within two solar 27-day cycles. The phase relation
between the MJO and the solar variation appears to be such that the MJO
predominantly transitions from phase 8 to 1 or from phase 4 and 5 during the
solar 27-day minimum. These results strongly depend on the MJO index used
such that the synchronization is most clearly seen when using univariate
indices like the OLR-based MJO index (OMI) in the analysis but can hardly be
seen with multivariate indices like the real-time multivariate MJO index
(RMM). One possible explanation could be that the synchronization pattern is
encoded particularly in the underlying outgoing longwave radiation (OLR)
data. A weaker dependence of the results on the underlying solar proxy is
also observed but not further investigated. Although we think that these initial indications are already worth noting, we do not claim to unambiguously prove this relationship in the
present study, neither in a statistical nor in a causal sense. Instead, we
challenge these initial findings ourselves in detail by varying underlying
datasets and methods and critically discuss resulting open questions to lay a
solid foundation for further research.
Ground-based ozone profiles over central Europe: incorporating anomalous observations into the analysis of stratospheric ozone trends
Authors: Bernet Leonie , von Clarmann Thomas , Godin-Beekmann Sophie , Ancellet Gérard , Maillard Barras Eliane , Stübi René , Steinbrecht Wolfgang , Kämpfer Niklaus , Hocke Klemens
Published: April 2019

Abstract. Observing stratospheric ozone is essential to assess whether the Montreal
Protocol has succeeded in saving the ozone layer by banning ozone depleting
substances. Recent studies have reported positive trends, indicating that
ozone is recovering in the upper stratosphere at mid-latitudes, but the trend
magnitudes differ, and uncertainties are still high. Trends and their
uncertainties are influenced by factors such as instrumental drifts, sampling
patterns, discontinuities, biases, or short-term anomalies that may all mask
a potential ozone recovery. The present study investigates how anomalies,
temporal measurement sampling rates, and trend period lengths influence
resulting trends. We present an approach for handling suspicious anomalies in
trend estimations. For this, we analysed multiple ground-based stratospheric
ozone records in central Europe to identify anomalous periods in data from
the GROund-based Millimetre-wave Ozone Spectrometer (GROMOS) located in Bern,
Switzerland. The detected anomalies were then used to estimate ozone trends
from the GROMOS time series by considering the anomalous observations in the
regression. We compare our improved GROMOS trend estimate with results
derived from the other ground-based ozone records (lidars, ozonesondes, and
microwave radiometers), that are all part of the Network for the Detection of
Atmospheric Composition Change (NDACC). The data indicate positive trends of
1 % decade−1 to 3 % decade−1 at an altitude of about
39 km (3 hPa), providing a confirmation of ozone recovery in
the upper stratosphere in agreement with satellite observations. At lower
altitudes, the ground station data show inconsistent trend results, which
emphasize the importance of ongoing research on ozone trends in the lower
stratosphere. Our presented method of a combined analysis of ground station
data provides a useful approach to recognize and to reduce uncertainties in
stratospheric ozone trends by considering anomalies in the trend estimation.
We conclude that stratospheric trend estimations still need improvement and
that our approach provides a tool that can also be useful for other data
sets.
The impact of solar radiation on polar mesospheric ice particle formation
Authors: Nachbar Mario , Wilms Henrike , Duft Denis , Aylett Tasha , Kitajima Kensei , Majima Takuya , Plane John M. C. , Rapp Markus , Leisner Thomas
Published: April 2019

Abstract. Mean temperatures in the polar summer mesopause can drop to 130 K. The low
temperatures in combination with water vapor mixing ratios of a few parts per
million give rise to the formation of ice particles. These ice particles may
be observed as polar mesospheric clouds. Mesospheric ice cloud formation is
believed to initiate heterogeneously on small aerosol particles (r<2 nm) composed of recondensed meteoric material, so-called meteoric
smoke particles (MSPs). Recently, we investigated the ice activation and
growth behavior of MSP analogues under realistic mesopause conditions. Based
on these measurements we presented a new activation model which largely
reduced the uncertainties in describing ice particle formation. However, this
activation model neglected the possibility that MSPs heat up in the
low-density mesopause due to absorption of solar and terrestrial irradiation.
Radiative heating of the particles may severely reduce their ice formation
ability. In this study we expose MSP analogues (Fe2O3 and
FexSi1−xO3) to realistic mesopause
temperatures and water vapor concentrations and investigate particle warming
under the influence of variable intensities of visible light (405, 488, and
660 nm). We show that Mie theory calculations using refractive indices of
bulk material from the literature combined with an equilibrium temperature
model presented in this work predict the particle warming very well.
Additionally, we confirm that the absorption efficiency increases with the
iron content of the MSP material. We apply our findings to mesopause
conditions and conclude that the impact of solar and terrestrial radiation on
ice particle formation is significantly lower than previously assumed.
First direct observation of sea salt aerosol production from blowing
snow above sea ice
Authors: Frey Markus M. , Norris Sarah J. , Brooks Ian M. , Anderson Philip S. , Nishimura Kouichi , Yang Xin , Jones Anna E. , Nerentorp Mastromonaco Michelle G. , Jones David H. , Wolff Eric W.
Published: April 2019

Abstract. Two consecutive cruises in the Weddell Sea, Antarctica, in winter 2013 provided the first direct observations of sea salt aerosol (SSA) production from blowing snow above sea ice, thereby validating a model hypothesis to account for winter time SSA maxima in polar regions not explained otherwise. Blowing or drifting snow always lead to increases in SSA during and after storms. Observed aerosol gradients suggest that net production of SSA takes place near the top of the blowing or drifting snow layer. The observed relative increase of SSA concentrations with wind speed suggests that on average the corresponding aerosol mass flux during storms was equal or larger above sea ice than above the open ocean, demonstrating the importance of the blowing snow source for SSA in winter and early spring. For the first time it is shown that snow on sea ice is depleted in sulphate relative to sodium with respect to sea water. Similar depletion observed in the aerosol suggests that most sea salt originated from snow on sea ice and not the open ocean or leads, e.g. on average 93 % during the 8 June and 12 August 2013 period. A mass budget calculation shows that sublimation of snow even with low salinity (
Atmospheric CO2, CH4, and CO with the CRDS technique at the Izaña Global GAW station: instrumental tests, developments, and first measurement results
Authors: Gomez-Pelaez Angel J. , Ramos Ramon , Cuevas Emilio , Gomez-Trueba Vanessa , Reyes Enrique
Published: April 2019

Abstract. At the end of
2015, a CO2/CH4/CO cavity ring-down spectrometer (CRDS) was
installed at the Izaña Global Atmosphere Watch (GAW) station (Tenerife,
Spain) to improve the Izaña Greenhouse Gases GAW Measurement Programme,
and to guarantee the renewal of the instrumentation and the long-term
maintenance of this program. We present the results of the CRDS
acceptance tests, the raw data processing scheme applied, and the response
functions used. Also, the calibration results, the implemented water vapor
correction, the target gas injection statistics, the ambient measurements
performed from December 2015 to July 2017, and their comparison with other
continuous in situ measurements are described. The agreement with other in
situ continuous measurements is good most of the time for CO2 and
CH4, but for CO it is just outside the GAW 2 ppb objective. It seems
the disagreement is not produced by significant drifts in the CRDS CO World
Meteorological Organization (WMO) tertiary standards. The more relevant
contributions of the present article are (1) determination of linear
relationships between flow rate, CRDS inlet pressure, and CRDS outlet valve
aperture; (2) determination of a slight CO2 correction that takes
into account changes in the inlet pressure/flow rate (as well as its
stability over the years), and attributing it to the existence of a small
spatial inhomogeneity in the pressure field inside the CRDS cavity due to the
gas dynamics; (3) drift rate determination for the pressure and temperature
sensors located inside the CRDS cavity from the CO2 and CH4
response function drift trends; (4) the determination of the H2O
correction for CO has been performed using raw spectral peak data instead of
the raw CO provided by the CRDS and using a running mean to smooth random
noise in a long water-droplet test (12 h) before performing the least square
fit; and (5) the existence of a small H2O dependence in the CRDS flow
and of a small spatial inhomogeneity in the temperature field inside the CRDS
cavity are pointed out and their origin discussed.
On the ion-inertial-range density-power spectra in solar wind turbulence
Authors: Treumann Rudolf A. , Baumjohann Wolfgang , Narita Yasuhito
Published: April 2019

Abstract. A model-independent first-principle first-order investigation of the shape of
turbulent density-power spectra in the ion-inertial range of the solar wind
at 1 AU is presented. Demagnetised ions in the ion-inertial range of
quasi-neutral plasmas respond to Kolmogorov (K) or Iroshnikov–Kraichnan (IK)
inertial-range velocity–turbulence power spectra via the spectrum of the
velocity–turbulence-related random-mean-square
induction–electric field. Maintenance of
electrical quasi-neutrality by the ions causes deformations in the power
spectral density of the turbulent density fluctuations. Assuming
inertial-range K (IK) spectra in solar wind velocity turbulence and referring
to observations of density-power spectra suggest that the occasionally
observed scale-limited bumps in the density-power spectrum may be traced back
to the electric ion response. Magnetic power spectra react passively to the
density spectrum by warranting pressure balance. This approach still neglects
contribution of Hall currents and is restricted to the ion-inertial-range
scale. While both density and magnetic turbulence spectra in the affected
range of ion-inertial scales deviate from K or IK power law shapes, the
velocity turbulence preserves its inertial-range shape in the process to
which spectral advection turns out to be secondary but may become observable
under special external conditions. One such case observed by WIND is
analysed. We discuss various aspects of this effect, including the affected
wave-number scale range, dependence on the angle between mean flow velocity
and wave numbers, and, for a radially expanding solar wind flow, assuming
adiabatic expansion at fast solar wind speeds and a Parker dependence of the
solar wind magnetic field on radius, also the presumable limitations on the
radial location of the turbulent source region.
Tropical and mid-latitude teleconnections interacting with the Indian summer monsoon rainfall: A Theory-Guided Causal Effect Network approach
Authors: Di Capua Giorgia , Kretschmer Marlene , Donner Reik V. , van den Hurk Bart , Vellore Ramesh , Krishnan Raghavan , Coumou Dim
Published: April 2019

Abstract. The Indian Summer Monsoon (ISM) is characterized by alternating active (wet) and break (dry) phases operating at sub-seasonal timescales, and various studies advocate tropical and mid-latitude teleconnection drivers influence the sub-seasonal ISM rainfall variability. One such driver is the circumglobal teleconnection pattern, which is commonly observed during boreal summer regulating the variability across the mid-latitudes at sub-seasonal time scales. In this study, a two-way interaction between ISM and circumglobal teleconnection is hypothesized and causal discovery algorithms are employed to examine and quantify the interaction linkage. Our analysis shows that there is a robust causal link from the circumglobal teleconnection pattern and the North Atlantic Oscillation (NAO) to ISM rainfall, and also a reverse causal link from the ISM rainfall to the circumglobal teleconnection pattern. Further, by including regional drivers in the framework, we identify the causal links that represent the internal dynamics associated with the ISM convective activity operating on weekly timescales, e.g., on weekly time scales, there is precedence of enhanced ascent to increased rainfall over the monsoon trough region which is followed by strong stabilization and convective inhibition. In our analyses, this internal ISM dynamics has the strongest effect, which is about twice as large as those of the mid-latitudes and of tropical MJO variability on the ISM dynamics. With our theory-guided causal effect network approach, we can (1) test physical hypotheses, (2) exploratively search for causal links and (3) quantify their relative causal contributions. This paves the way for improved (sub)seasonal forecasts.
Characterization of Hillslope Hydrologic Events Using Machine Learning Algorithms
Authors: Lee Eunhyung , Kim Sanghyun
Published: April 2019

Abstract. Time series of soil moisture were measured at 30 points for 396 rainfall events on a steep, forested hillslope between 2007 and 2016. We then analyzed the dataset using an unsupervised machine learning algorithm to cluster the hydrologic events based on the dissimilarity distances between weighting components of a self-organizing map (SOM). Generation patterns of two primary hillslope hydrological processes, namely, vertical flow and lateral flow, at the upslope and downslope areas were responsible for the distinction of the hydrologic events. Two-dimensional spatial weighting patterns in the SOM provided explanations for the relationships between rainfall characteristics and hydrological processes at different locations and depths. High reliability in hydrologic classification was achieved for both the driest and wettest events; as assessed through k-fold cross validation using 10 years of data. Representative soil moisture monitoring points were found through temporal stability analysis of the event structure delineated from the machine learning classification. Application of a supervised machine learning algorithm provided a scheme using soil moisture for the cluster identification of hydrologic event even without rainfall data which is useful to configure hillslope hydrologic process with the least cost in data acquisition.
Laparoscope arm automatic positioning for robot-assisted surgery based on reinforcement learning
Authors: Yu Lingtao , Yu Xiaoyan , Chen Xiao , Zhang Fengfeng
Published: April 2019

Abstract. Compared with the traditional laparoscopic surgery, the
preoperative planning of robot-assisted laparoscopic surgery is more complex
and essential. Through the analysis of the surgical procedures and surgical
environment, the laparoscope arm preoperative planning algorithm based on
the artificial pneumoperitoneum model, lesion parametrization model is
proposed, which ensures that the laparoscope arm satisfies both the distance
principle and the direction principle. The algorithm is divided into two
parts, including the optimum incision and the optimum angle of laparoscope
entry, which makes the laparoscope provide a reasonable initial visual
field. A set of parameters based on the actual situation is given to
illustrate the algorithm flow in detail. The preoperative planning algorithm
offers significant improvements in planning time and quality for
robot-assisted laparoscopic surgery. The improved method which combines the
preoperative planning algorithm with deep deterministic policy gradient
algorithm is applied to laparoscope arm automatic positioning for the
robot-assisted laparoscopic surgery. It takes a fixed-point position and
lesion parameters as input, and outputs the optimum incision, the optimum
angle and motor movements without kinematics. The proposed algorithm is
verified through simulations with a virtual environment built by pyglet. The
results validate the correctness, feasibility, and robustness of this
approach.
Ionian Abyssal Plain: a window into the Tethys oceanic lithosphere
Authors: Dannowski Anke , Kopp Heidrun , Klingelhoefer Frauke , Klaeschen Dirk , Gutscher Marc-André , Krabbenhoeft Anne , Dellong David , Rovere Marzia , Graindorge David , Papenberg Cord , Klaucke Ingo
Published: April 2019

Abstract. The nature of the Ionian Sea crust has been the subject
of scientific debate for more than 30 years, mainly because seismic imaging
of the deep crust and upper mantle of the Ionian Abyssal Plain (IAP) has not
been conclusive to date. The IAP is sandwiched between the Calabrian and
Hellenic subduction zones in the central Mediterranean. A NNE–SSW-oriented
131 km long seismic refraction and wide-angle reflection profile, consisting
of eight ocean bottom seismometers and hydrophones, was acquired in 2014.
The profile was designed to univocally confirm the proposed oceanic nature
of the IAP crust as a remnant of the Tethys and to confute its
interpretation as a strongly thinned part of the African continental crust.
A P-wave velocity model developed from travel-time forward modelling is
refined by gravimetric data and synthetic modelling of the seismic data. A
roughly 6–7 km thick crust with velocities ranging from 5.1 to 7.2 km s−1, top to bottom, can be traced throughout the IAP. In the vicinity of
the Medina seamounts at the southern IAP boundary, the crust thickens to
about 9 km and seismic velocities decrease to 6.8 km s−1 at the crust–mantle
boundary. The seismic velocity distribution and depth of the crust–mantle
boundary in the IAP document its oceanic nature and support the
interpretation of the IAP as a remnant of the Tethys lithosphere with the
Malta Escarpment as a transform margin and a Tethys opening in the NNW–SSE
direction.
Benchmark seasonal prediction skill estimates based on regional indices
Authors: Walsh John E. , Stewart J. Scott , Fetterer Florence
Published: April 2019

Abstract. Basic statistical metrics such as autocorrelations and across-region lag
correlations of sea ice variations provide benchmarks for the assessments of
forecast skill achieved by other methods such as more sophisticated
statistical formulations, numerical models, and heuristic approaches. In this
study we use observational data to evaluate the contribution of the trend to
the skill of persistence-based statistical forecasts of monthly and seasonal
ice extent on the pan-Arctic and regional scales. We focus on the Beaufort
Sea for which the Barnett Severity Index provides a metric of historical
variations in ice conditions over the summer shipping season. The variance
about the trend line differs little among various methods of detrending
(piecewise linear, quadratic, cubic, exponential). Application of the
piecewise linear trend calculation indicates an acceleration of the winter
and summer trends during the 1990s. Persistence-based statistical forecasts
of the Barnett Severity Index as well as September pan-Arctic ice extent show
significant statistical skill out to several seasons when the data include
the trend. However, this apparent skill largely vanishes when the data are
detrended. In only a few regions does September ice extent correlate
significantly with antecedent ice anomalies in the same region more than 2
months earlier. The springtime “predictability barrier” in regional
forecasts based on persistence of ice extent anomalies is not reduced by the
inclusion of several decades of pre-satellite data. No region shows
significant correlation with the detrended September pan-Arctic ice extent at
lead times greater than a month or two; the concurrent correlations are
strongest with the East Siberian Sea. The Beaufort Sea's ice extent as far
back as July explains about 20 % of the variance of the Barnett Severity
Index, which is primarily a September metric. The Chukchi Sea is the only
other region showing a significant association with the Barnett Severity
Index, although only at a lead time of a month or two.
Multipoint high-fidelity CFD-based aerodynamic shape optimization of a 10 MW wind turbine
Authors: Madsen Mads H. Aa. , Zahle Frederik , Sørensen Niels N. , Martins Joaquim R. R. A.
Published: April 2019

Abstract. The wind energy industry relies heavily on computational fluid dynamics (CFD)
to analyze new turbine designs. To utilize CFD earlier in the design
process, where lower-fidelity methods such as blade element momentum (BEM)
are more common, requires the development of new tools. Tools that utilize
numerical optimization are particularly valuable because they reduce the
reliance on design by trial and error. We present the first comprehensive 3-D
CFD adjoint-based shape optimization of a modern 10 MW offshore wind
turbine. The optimization problem is aligned with a case study from
International Energy Agency (IEA) Wind Task 37, making it possible to compare
our findings with the BEM results from this case study and therefore allowing
us to determine the value of design optimization based on high-fidelity
models. The comparison shows that the overall design trends suggested by the
two models do agree, and that it is particularly valuable to consult the
high-fidelity model in areas such as root and tip where BEM is inaccurate. In
addition, we compare two different CFD solvers to quantify the effect of
modeling compressibility and to estimate the accuracy of the chosen grid
resolution and order of convergence of the solver. Meshes up to 14×106 cells are used in the optimization whereby flow details are resolved.
The present work shows that it is now possible to successfully optimize
modern wind turbines aerodynamically under normal operating conditions using
Reynolds-averaged Navier–Stokes (RANS) models. The key benefit of a 3-D RANS
approach is that it is possible to optimize the blade planform and
cross-sectional shape simultaneously, thus tailoring the shape to the actual
3-D flow over the rotor. This work does not address evaluation of extreme
loads used for structural sizing, where BEM-based methods have proven very
accurate, and therefore will likely remain the method of choice.
Spectral inclusions between $(\alpha+1)$-times integrated semigroups and its generators
Authors: Tajmouati Abdelaziz , El Bakkali Abdeslam , Mohamed Ahmed Mohamed Baba
Published: April 2019

We interest to $\alpha$-times integrated semigroups that are the solution of the $(\alpha+1)$-times integrated Cauchy problems. Particulary, we characterize partially the different spectrums of $\alpha$-times integrated semigroups using the spectrums of its generators.
C*-algebras generated by isometries and true representations
Authors: Ahmed Mamoon
Published: April 2019

Let (G; P) be a quasi-lattice ordered group. In this paper we present a modied proof of Laca and Raeburn's theorem about the covariant isometric representations of amenable quasi-lattice ordered groups [7, Theorem 3.7], by following a two stage strategy. First, we construct a universal covariant representation for a given quasi-lattice ordered group (G; P) and show that it is unique. The construction of this object is new; we have not followed either Nica's approach in [10] or Laca and Raeburn's approach in [7], although all three objects are essentially the same. Our approach is a very natural one and avoids some of the intricacies of the other approaches. Then we show if (G; P) is amenable, true representations of (G; P) generate C-algebras which are canonically isomorphic to the universal object.
Three weak solutions for a class of Neumann boundary value systems involving the (p1,...,pn)-Laplacian
Authors: Hadjian Armin
Published: April 2019

In this paper, we establish the existence of two intervals ofpositive real parameters $\lambda$ for which a class of Neumannboundary value equations involving the (p1,...,pn)-Laplacianadmits three weak solutions, whose norms are uniformly bounded withrespect to $\lambda$ belonging to one of the two intervals. Theapproach is based on variational methods.
The Role of Work-Life Balance and Worker Scheduling Flexibility in Predicting Global Comparative Job Satisfaction
Authors: Andrade Maureen Snow , Westover Jonathan H , Kupka Bernd A
Published: April 2019

Prior research has indicated that the nature of work has changed dramatically in recent years in response to economic shifts and an increasingly global economy. In part, this shift has resulted in a greater efficacy of various work-life balance and worker schedule flexibility elements in the experiences of employees in the workplace. However, little is known about the overall comparative quality of work and job satisfaction around the world in response to a shifting and increasingly interconnected global economy. In this study, we use non-panel longitudinal data from the most recent wave of the International Social Survey Program (Work Orientations IV, 2015) to conduct an exploratory comparative analysis of the impact of various workplace conditions, job characteristics, and employee attitudes in relation to comparative job satisfaction across the globe, with a special focus on the role of work-life balance and worker scheduling flexibility. Employees across the globe respond quite differently to work scenarios, which poses challenges for companies operating in multiple countries, requires adjustments to human resource practices to optimize performance levels of employees and reduce turnover expenses, and should caution managers to scrutinize their procedures to adjust to new demands in the workplace. This study adds value by making global comparisons of various workplace factors and their impact on job satisfaction using a database reflecting practices in 37 countries.
Military Doctrine Development and Curriculum Development
Authors: Walden Joseph L.
Published: April 2019

One of the complaints about the development of military doctrine over the past several decades is that “we arealways preparing to fight the last war.” One of the complaints that surfaced during a four year long study into thedevelopment of a common framework for supply chain management curriculum development was that the text booksused in the curriculum development process were out of date. In other words, we are preparing students for the realworld by teaching them about the historical business world and not the emerging business world. While thisapproach may work in the liberal arts such as history, it is in the words of Freire, doing a disservice to the studentsand not adequately preparing them for the real world. This study looks at a methodology for developing businessschool curriculums in particular. The study reviewed syllabi, job announcements, and textbooks for the top ratedschools and for those not in the Top 25. The gap between what industry is asking for and what schools are teaching ismuch wider for the not-Top 25 schools than for the top ranked schools.