bluuebunny/crossref_metadata_2025_split huggingface dataset:
Research needs in systems engineering: Report from a University of Alabama in Huntsville workshop
Authors: White Christopher J. , Mesmer Bryan L. 
Published: June 2019

AbstractThe success of systems engineering (SE) efforts to solve development issues benefit from the mutually advantageous relationship between academia and practice. This relationship can be threatened by lag in adoption and differences in focus between the two worlds. In an effort to help maintain alignment between SE research and practice, a 2‐day workshop was held at the University of Alabama in Huntsville on research needs in SE. The workshop was attended by individuals from academia, the Department of Defense, NASA, and the aerospace industry. This paper presents summaries of the discussions that took place, as well as possible research questions informed by the results of the workshop. The workshop consisted of an introductory roundtable and three breakouts sessions focusing on requirements, verification, and validation; configuration and data management; and systems acquisition and design. Several topics emerged as important concepts for future research, and research questions were developed relating to model‐based systems engineering (MBSE), requirements, modeling, sociotechnical issues, and education.
Review of numerical solution of Richardson–Richards equation for variably saturated flow in soils
Authors: Zha Yuanyuan , Yang Jinzhong , Zeng Jicai , Tso Chak‐Hau M. , Zeng Wenzhi , Shi Liangsheng 
Published: June 2019

AbstractModeling variably saturated flow in the vadose zone is of vital importance to many scientific fields and engineering applications. Richardson–Richards equation (RRE, which is conventionally known as Richards' equation) is often chosen to physically represent the fluxes in the vadose zone when the accurate characterization of the soil water dynamics is required. Being a highly nonlinear partial differential equation, RRE is often solved numerically. Although there are mature software and codes available for simulating variably saturated flow by solving RRE, the numerical solution of RRE is nevertheless computationally expensive. Moreover, sometimes the robustness and the efficiency of RRE‐based models can deteriorate rapidly when certain unfavorable conditions are met. These demerits of RRE hinder its application on large‐scale vadose zone hydrology problems and uncertainty quantification, both of which requires many runs of the prediction model. To address these challenges, the accuracy, convergence, and efficiency of the numerical schemes of RRE should be further improved by testing a wide variety of cases covering different initial conditions, boundary conditions, and soil types. We reviewed and highlighted several critical issues related to the numerical modeling of RRE, including spatial and temporal discretization, the different forms of RREs, iterative and noniterative schemes, benchmark solutions, and available software and codes. Based on the review, we summarize the challenges and future work for solving RRE numerically.This article is categorized under:
Science of Water > Hydrological Processes
Science of Water > Methods
Bond zone model for a conductive crack at the interface of piezoelectric materials under anti‐plane mechanical and in‐plane electric loadings
Authors: Onopriienko Oleg , Loboda Volodymyr , Sheveleva Alla , Lapusta Yuri 
Published: June 2019

AbstractAn electrically conductive crack between two semi‐infinite piezoelectric spaces under the action of anti‐plane mechanical loading and in‐plane electrical field parallel to the crack faces is considered. An exact analytical solution of this problem is found and the oscillating singularity is revealed at the crack tips. A new model, which is free from oscillation, is also developed for a conductive interface crack. This model is based on the introduction of a mechanically bonded zone at the conducting crack tip characterizing by zero crack faces displacement jump. The most reasonable length of this zone is found from the condition of a smooth crack closing. The validity confirmation of the bond zone model is given by means of description of conductive crack formation process. Some recommendations concerning the use of suggested model for the study of finite and infinite sized bodies with electrically conducting interface cracks are formulated.
Social interaction analysis in captive orcas (Orcinus orca)
Authors: Sánchez–Hernández Paula , Krasheninnikova Anastasia , Almunia Javier , Molina–Borja Miguel 
Published: June 2019

AbstractThe management of socially complex species in captivity is challenging. Research on their social behavior improves our understanding of interactions in captive animals and captive‐group management. We conducted a detailed analysis of social relationships shown by the orcas kept at Loro Parque zoo and their tendency to reconcile after aggressive episodes. Affiliative interactions were the most frequent social activities compared to agonistic or sexual interactions. Within affiliative behaviors, we documented the pattern “gentle tongue bite”, where an animal touches the other's tongue with his teeth but does not bite it. Affiliative interactions between a specific pair of orcas occurred significantly more often than expected by chance, and together with low levels of agonistic interactions, indicated particular affinity between some individuals. The most frequently observed low‐level agonistic relationship was that of the two older males (Tekoa–Keto); however, they also showed frequent sexual and affiliative interactions. Sexual‐like behaviors (pursuit, mount, and penis between males) were found in both sexes. Finally, the observed corrected conciliatory tendency (31.57%) was within the range described for other primate and cetacean species. This study provides a systematic way to assess social interactions as well as conflict management strategies in cetaceans housed in zoos and zoo‐like facilities and may help to improve animal welfare and management of animals in controlled environments.
Testing Device for Radon Migration Experiments, the Construction and Preliminary Results
Authors: Bonczyk M. , Chałupnik S. , Howaniec N. , Smoliński A. , Wysocka M. 
Published: June 2019

AbstractThe main goal of the research presented was to design and construct a device, enables estimation of the diffusion time and diffusion length for radon in core samples collected from the geological layers of Upper Silesian Coal Basin (USCB). Another goal will be investigations of the advection of 222Rn with other gases like carbon dioxide or methane, occurring in the Carboniferous strata in USCB. This knowledge will support the precision of the assessment of radon hazard in working environment. Moreover, it should give an answer to some questions, related to the radon migration issues—if the results of measurements of the transport of radon with other gases in the strata could be applied for the prediction of geodynamic phenomena in the mining areas, like tremors and outbursts. The study was focused on the flow measurements of the following gases: radon, carbon dioxide, nitrogen and their mixtures, as the use of methane was excluded due to potential hazard of explosion. In this article results of measurements of diffusive migration are presented: radon itself and simultaneous migration of radon, nitrogen and carbon dioxide. For this purpose a special device was designed and constructed. This device consists of the container for the sample of coal, mineral or rock and two reservoirs—the inlet and outlet one. The gas (e.g. air or carbon dioxide) with radon is introduced into inlet reservoir, while the content of marker gases and radon is monitored in the outlet reservoir. The preliminary experiments were also performed and are presented in this paper. In the literature, there are only rare results of such investigations, while our previous research in USCB region showed some correlation between sudden changes of radon level and geodynamic events. Therefore, the results of the investigations presented in this study are expected to contribute to the improvement of the models of these phenomena. The future work planned will be aimed at investigations of advective flow of radon with various carrier gases.
Paradoxical lucidity: A potential paradigm shift for the neurobiology and treatment of severe dementias
Authors: Mashour George A. , Frank Lori , Batthyany Alexander , Kolanowski Ann Marie , Nahm Michael , Schulman‐Green Dena , Greyson Bruce , Pakhomov Serguei , Karlawish Jason , Shah Raj C. 
Published: June 2019

AbstractUnexpected cognitive lucidity and communication in patients with severe dementias, especially around the time of death, have been observed and reported anecdotally. Here, we review what is known about this phenomenon, related phenomena that provide insight into potential mechanisms, ethical implications, and methodologic considerations for systematic investigation. We conclude that paradoxical lucidity, if systematically confirmed, challenges current assumptions and highlights the possibility of network‐level return of cognitive function in cases of severe dementias, which can provide insight into both underlying neurobiology and future therapeutic possibilities.
Separated After a Disaster: Trust and Privacy Issues in Sharing Children’s Personal Information
Authors: Charney Rachel L. , Rebmann Terri , Esposito Flavio , Schmid Kristin , Chung Sarita 
Published: June 2019

ABSTRACTBackground:After disasters, unaccompanied children may present to an emergency department requiring reunification. An effective reunification system depends on the willingness of guardians to utilize it.Objective:Assess guardian willingness to share children’s personal information for reunification purposes after a disaster, perceived concerns and beliefs, and trust in reunification agencies.Methods:Guardians of children presenting to 2 pediatric emergency departments were approached to participate in a survey-based study. Willingness to share their children’s personal information was scored on a scale of 1 to 19 (1 point per item). Perceived concerns about and importance of sharing information, level of trust in reunification agencies, and guardian demographics were collected. Chi-square was used to compare trust and attitudes/beliefs. Multivariate linear regression was used to determine factors associated with willingness to share information.Results:A total of 363 surveys were completed (response rate, 80%). Most guardians (95.6%) were willing to share at least some information (mean, 16 items; range, 1-19). Half were concerned about protection (55.4%) or abuse (52.3%) of their child’s information. Hospitals were trusted more than other reunification agencies (P < .001). Perception of reunification importance was associated with willingness to share (P < .001).Conclusions:Guardians are willing to share their children’s information to facilitate reunification after disasters, but have privacy concerns.
Three-dimensional visualization of top-down superimposed thrust sheets in the SW Grenville Province, Ontario
Authors: Strong Jacob W.D. , Dickin Alan P. 
Published: June 2019

AbstractTo properly understand the tectonic history of the Grenville Province it is necessary to have a reliable, scientifically based understanding of the present-day three-dimensional (3D) structure of the orogen. Based on detailed Nd isotope mapping of surface boundaries and Lithoprobe seismic sections, this study provides the first detailed visualization of the 3D structure of the Grenville gneiss belt in Ontario using the SketchUp software package. The 3D visualization supports a model in which thrust geometry was imposed from the top downwards, controlled by the NW boundary of the Central Metasedimentary Belt that originated as a failed back-arc rift zone. The Central Metasedimentary Belt boundary controlled the trajectory of the Allochthon Boundary Thrust, its underlying tectonic duplex and, ultimately, the Grenville Front. This process of superimposed thrusting explains the large-scale change in the trajectory of the Grenville Front north of Georgian Bay that has been called the ‘Big Bend’. To assist in visualizing the 3D model, a fly-through animation is provided in the supplementary material.
Holding agencies accountable: Exploring the effect of oversight on citizens’ approval of members of Congress
Authors: Miller Susan M. , Ruder Alexander I. 
Published: June 2019

AbstractWe seek to understand the incentives facing Congress members to hold executive agencies accountable. Specifically, we explore whether Congress members are rewarded for taking politically costly oversight actions. We evaluate the effect of oversight activities on citizens’ evaluations of Congress members, taking into account the member’s partisanship, the citizen’s partisanship and agency ideology. Using a survey experiment, we find evidence that citizens’ evaluations of members are affected by the members’ oversight activity, with both copartisan and cross-party members rewarded for oversight efforts. Politically costly actions against ally agencies, however, do not appear to be rewarded to a greater extent by copartisans. These results provide insight into the way in which citizens interpret oversight activities by Congress members, suggesting that while good governance actions hold value for citizens, costly oversight actions aimed at ally agencies are not rewarded by copartisan citizens more than politically expedient oversight actions.
Theoretical Study of Global Scale Analysis Method for Agile Bionic Leg Mechanism
Authors: Zang Hongbin , Zhao Dengfeng , Shen Lianguan 
Published: June 2019

SummaryAgile bionic leg mechanism (ABLM) has attracted more and more attention in the development of jumping robots and high-speed running robots. However, theoretical study of the global structure for motility characteristics and its evolution is few. By using the modern mathematical tools such as singular theory, geometric topology, and group theory, a global scale analysis method for kinematic performance of mechanisms is proposed. Taking 6-bar with two rings mechanism as an example, a detailed analysis process is studied. The 6-bar ABLM designed by this theory is verified by virtual prototype simulation experiment. The global scale analysis of 4-bar linkage is also carried out by using this method, and the result is compared with the “Grashof criterion” to verify the correctness of this method. It provides a general theory and method for innovative design and global scale analysis of ABLM.
A self-tracking study of international students in France: Exploring opportunities for language and cultural learning
Authors: Guichon Nicolas 
Published: June 2019

AbstractThis exploratory study focuses on international students’ usage of digital tools in order to understand what role such tools play in the transition to their new academic environments and what learning opportunities they provide. Not only do digital tools accompany international students’ social, cultural, and linguistic transitions as they move to France to further their language competence, but their usage also reveals part of the social and semiotic adjustments they have to make in the process. Sixteen international students who volunteered for the study were given a smartphone application with which they could track learning opportunities by taking pictures and writing textual commentaries. The data, collected over a period of five weeks, thus include the resulting entries these participants shared in their mobile multimodal diaries with the researchers, as well as an end-of-project debriefing that was conducted to shed further light on the international students’ digital habits and their attitudes towards self-tracking. This study indicates that digital tools can play an important and pervasive role in facilitating international students’ linguistic development and their dealings with everyday life abroad. It also confirms that self-tracking apps can be instrumental in enhancing students’ awareness of learning opportunities outside the classroom.
Prevalence of underweight in children and adolescents (aged 3–18 years) from Kraków (Poland) in 1983 and 2010
Authors: Kowal Małgorzata , Woz´niacka Renata , Bac Aneta , Z˙aro´w Ryszard 
Published: June 2019

AbstractObjective:To estimate the changes in the prevalence of underweight among girls and boys living in Kraków that occurred between 1983 and 2010.Design:The study was based on two cross-sectional surveys conducted in 1983 and 2010. The prevalence of underweight was estimated based on the International Obesity Task Force (IOTF) and Centers for Disease Control and Prevention (CDC) cut-off points.Setting:The study was conducted in Kraków, Poland.Participants:Children aged 3–18 years (n5245).Results:Between 1983 and 2010 the prevalence of underweight decreased in both sexes. Using the IOTF criteria, the prevalence of underweight decreased from 10·5 to 10·3 % in girls and from 8·9 to 7·5 % in boys, but it was still higher in girls than in boys. According to the CDC criteria, this prevalence decreased from 5·1 to 4·4 % and from 5·9 to 4·6 %, respectively, and was slightly lower in girls. According to the IOTF criteria, underweight prevalence increased slightly during childhood in both sexes while according to the CDC criteria it decreased in boys and did not change in girls. Among juveniles and adolescents, it decreased regardless of the method used.Conclusions:The frequency of underweight in the population of children and adolescents from Kraków changed slightly in 1983 and 2010 despite economic and social changes. Depending on the cut-off points used, not only the magnitude but also the direction of changes between series could be different. In order to aid global monitoring, the prevalence of underweight as well as overweight should always be evaluated by several methods.
A Logic Framework for P2P Deductive Databases
Authors: CAROPRESE LUCIANO , ZUMPANO ESTER 
Published: June 2019

AbstractThis paper presents a logic framework for modeling the interaction among deductive databases in a peer-to-peer (P2P) environment. Each peer joining a P2P systemprovides or imports datafrom its neighbors by using a set ofmapping rules, that is, a set of semantic correspondences to a set of peers belonging to the same environment. By using mapping rules, as soon as it enters the system, a peer can participate and access all data available in its neighborhood, and through its neighborhood it becomes accessible to all the other peers in the system. A query can be posed to any peer in the system and the answer is computed by using locally stored data and all the information that can be consistently imported from the neighborhood. Two different types of mapping rules are defined: mapping rules allowing to import a maximal set of atoms not leading to inconsistency (calledmaximal mapping rules) and mapping rules allowing to import a minimal set of atoms needed to restore consistency (calledminimal mapping rules). Implicitly, the use of maximal mapping rules statesit is preferable to import as long as no inconsistencies arise; whereas the use of minimal mapping rules states thatit is preferable not to import unless a inconsistency exists. The paper presents three different declarative semantics of a P2P system: (i) theMax Weak Model Semantics, in which mapping rules are used to importas much knowledge as possiblefrom a peer’s neighborhood without violating local integrity constraints; (ii) theMin Weak Model Semantics, in which the P2P system can be locally inconsistent and the information provided by the neighbors is used to restore consistency, that is, to only integrate the missing portion of a correct, but incomplete database; (iii) theMax-Min Weak Model Semanticsthat unifies the previous two different perspectives captured by the Max Weak Model Semantics and Min Weak Model Semantics. This last semantics allows to characterize each peer in the neighborhood as a resource used either to enrich (integrate) or to fix (repair) the knowledge, so as to define a kind ofintegrate–repairstrategy for each peer. For each semantics, the paper also introduces an equivalent and alternative characterization, obtained by rewriting each mapping rule into prioritized rules so as to model a P2P system as a prioritized logic program. Finally, results about the computational complexity of P2P logic queries are investigated by consideringbraveandcautiousreasoning.
Role of Latent Heating Vertical Distribution in the Formation of the Tropical Cold Trap
Authors: Chang Kai‐Wei , L'Ecuyer Tristan S. 
Published: June 2019

AbstractThis study examines the role of latent heating (LH) vertical distribution in tropical tropopause layer (TTL) cooling and upper‐tropospheric warming associated with equatorial wave responses using LH from the Tropical Rainfall Measurement Mission and temperature from radio occultation observations. We distinguish the effects of convective and stratiform LH in tropical convection on temperature in the upper troposphere and lower stratosphere. Cross‐spectral analysis of time series of temperature and LH shows that stratiform LH exhibits higher coherence with temperature throughout most of the upper troposphere and lower stratosphere, especially in the equatorial Rossby wave response. Coherence between total LH and temperature tends to increase with the altitude of heating. Highest coherences occur almost exclusively at time scales of the Madden‐Julian Oscillation, suggesting the importance of mesoscale convective activity in TTL cooling and subsequent dehydration processes. These results demonstrate that TTL and upper‐tropospheric temperature perturbations depend on the vertical distribution of LH and that stratiform LH release has strong relationship with the formation of the horseshoe‐shaped cold trap over the Maritime Continent and West Pacific.
Instabilities of Finite‐Amplitude Internal Wave Beams
Authors: Onuki Y. , Tanaka Y. 
Published: June 2019

AbstractBeam‐like internal waves are commonly generated by tides in the ocean, but their dissipation processes that cause vertical mixing remain poorly understood. Previous studies examined small‐amplitude beams to find that parametric subharmonic instability (PSI) induces latitude‐dependent wave dissipation. Using a novel approach based on Floquet theory, this study analyzes the stability of finite‐amplitude beams over a wide range of parameters. If beam amplitude is small, PSI is indeed the principal mode under the condition f/σ ≤ 0.5, where f is the Coriolis parameter and σ is the beam frequency, and the growth rate is maximum when equality holds. However, as beam amplitude is increased, instability arises even when f/σ>0.5, but the location of maximum instability shifts toward lower f/σ; thus, the latitudinal dependence of instability is significantly altered. Furthermore, the resulting energy spectrum is strongly Doppler shifted to higher frequencies, which therefore distinguishes this configuration from the common cases of PSI.