bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coping with the loss of large, energy‐dense prey: a potential bottleneck for Weddell Seals in the Ross Sea
Authors: Salas Leo , Nur Nadav , Ainley David , Burns Jennifer , Rotella Jay , Ballard Grant 
Published: September 2016

AbstractExtraction of Antarctic toothfish (Dissostichus mawsoni) in the Ross Sea began in 1997, following a management plan that targets the largest fish with a goal of reducing the spawning biomass by 50% over 35 yr. We investigate the potential long‐term consequences of the reduced availability of this prey for Weddell seals (Leptonychotes weddellii). Energy demands in seals are acute, especially immediately following lactation, when females must recover substantial mass and cope with molting costs. We tested the hypothesis that toothfish are critically important for adult female seals during this period. Toothfish body mass is three orders of magnitude greater, and its energy density nearly double that of the most common seal prey, Antarctic silverfish (Pleuragramma antarcticum). Reduction or elimination of toothfish consumption could impair a female's ability to sufficiently recover and successfully produce a pup in the following pupping season. Our goals are to (1) illustrate mechanisms and conditions whereby toothfish depletion might plausibly affect seal population trends; (2) identify measurable parameters of the seals' ecology that may help better understand the potential negative impact of toothfish depletion on seal populations; and (3) promote a precautionary management approach for the fishery that includes monitoring of seal populations We constructed a set of inter‐linked models of seal diving behavior, physiological condition, and demography based on existing information. We evaluate the effect of the following factors on seal mass recovery and intrinsic population growth rates: fishery depletion rate, daily diving limits, probability of a successful dive, and body mass recovery target. We show that loss of toothfish has the greatest potential impact on seal populations' growth rate. Under some scenarios, populations may decrease at >10% per year. Critical parameters to better understand fishery impacts include prevalence and size of toothfish in the seals' diet; the relationship between diet and the rate of mass recovery; and female breeding propensity in relation to body condition at the end of the molting period. Our results lend support to concerns about the potential negative impact of toothfish extraction in the Ross Sea; and to advocate for a precautionary management approach by the fishery.
Disentangling the factors driving tree reproduction
Authors: Davi Hendrik , Cailleret Maxime , Restoux Gwendal , Amm Annabelle , Pichot Christian , Fady Bruno 
Published: September 2016

AbstractSeed production is a strong indicator of plant fitness and plays a major role in population dynamics. However, the environmental and endogenous factors driving seed production are still poorly described and are often hard to disentangle. Consequently, we combined principal components analysis and mixed‐effects linear models that can consider the multicollinearity of the explanatory variables and quantify their respective influence on the spatio‐temporal variability in reproduction. We applied this method to analyze the relationships between cone production in Abies alba Mill. trees (6829 individual reports of cone production). We estimated the relationships between cone production and climate, elevation, tree size (diameter and height), age, crown defoliation rate, and past radial growth. We found that the distribution of annual cone production was highly skewed; 21% of the trees did not produce any cones, whereas 3.7% produced more than 100 cones in a single year. Among the endogenous factors, tree size explained 57% of the variation in cone production with large trees being the most productive. Low radial growth rates in previous years were mostly associated with higher cone production (14% of the variation), while elevation and crown defoliation had non‐monotonic effects on reproduction. Finally, years of high cone production were strongly correlated with the difference between the April temperatures of the two previous years and were also associated with a dry spring 2 yr prior to cone production followed by a humid spring the previous year. These results highlight the complexity of the abiotic and biotic factors involved in reproduction and their respective and interactive influence on the interannual and interindividual variability in cone production.
Proposal of Vibration Control Reducing 2nd Radial Electromagnetic Force
Authors: HARA TAKAFUMI , AOYAGI SHIGEHISA , AJIMA TOSHIYUKI , IWAJI YOSHITAKA , YOSHIZU RIKIYA 
Published: September 2016

SUMMARYA permanent‐magnet synchronous motor (PMSM) with a concentrated winding generates vibration and noise resulting from the 2nd radial electromagnetic force. In preceding research, it has been shown that the D‐axis negative current reduces the 2nd radial electromagnetic force. In contrast, a relationship between this force and the current has not been clarified. In this paper, it is demonstrated that this force is separated into three forces caused by the D‐axis current, the Q‐axis current, and the flux of the magnet. An equation correlating this force and the current is developed by using a finite element analysis. On the basis of this equation, vibration control is proposed to reduce this force. In addition, this proposed method is verified by experiment.
Biohydrocarbons Production under Standard Refinery Conditions by means of a Representative Ketal Compound of Biocrude
Authors: Batalha Nuno , Pinto Joana , Ferreira Heitor , Baptista Daniella C. , Miranda Leandro S. M. , Pereira Marcelo M. 
Published: September 2016

AbstractAny standard oil refinery is based on mature processes that have been adapted to poorly reactive hydrocarbon feeds. In contrast, biomass‐derived compounds are highly functionalized and reactive compared to hydrocarbons. The goal to connect these two different chemical worlds is simple: to transform biomass by ketalization under mild conditions (≈120 °C) to afford a biocrude that is composed of ketal derivatives; 1,2:3,5‐di‐O‐isopropylidene‐β‐d‐xylofuranose (DX) is present in the range of 20–30 wt % in biocrude. Herein, DX mixed in n‐hexane was used as a model under cracking and hydrotreatment conditions. A mixture of DX up to 30 wt % in n‐hexane was converted at 500 °C in fixed‐bed reactor under continuous flow using ZSM‐5 and USY zeolites as catalysts. Remarkably, ZSM‐5 was able to convert DX into monoaromatics. At 1.5 min residence time, 64–94 % of DX was converted into monoaromatics. Additionally, ZSM‐5 showed a coke yield lower than 4 wt %. In contrast, USY increased the coke yield by 10‐fold and afforded fewer monoaromatics. A DX mixture up to 30 % in n‐hexane was converted fully by hydrotreatment in a fixed‐bed reactor using Pd‐USY as the catalyst at 300 °C and 30 bar to produce saturated hydrocarbons only up to 12 atoms. 13C‐labeled DX (in all 13C‐xylofuranose) showed indubitably that xylofuranose carbon atoms were converted into hydrocarbons.
Disentangling disorders of consciousness: Insights from diffusion tensor imaging and machine learning
Authors: Zheng Zhong S. , Reggente Nicco , Lutkenhoff Evan , Owen Adrian M. , Monti Martin M. 
Published: September 2016

AbstractPrevious studies have suggested that disorders of consciousness (DOC) after severe brain injury may result from disconnections of the thalamo‐cortical system. However, thalamo‐cortical connectivity differences between vegetative state (VS), minimally conscious state minus (MCS−, i.e., low‐level behavior such as visual pursuit), and minimally conscious state plus (MCS+, i.e., high‐level behavior such as language processing) remain unclear. Probabilistic tractography in a sample of 25 DOC patients was employed to assess whether structural connectivity in various thalamo‐cortical circuits could differentiate between VS, MCS−, and MCS+ patients. First, the thalamus was individually segmented into seven clusters based on patterns of cortical connectivity and tested for univariate differences across groups. Second, reconstructed whole‐brain thalamic tracks were used as features in a multivariate searchlight analysis to identify regions along the tracks that were most informative in distinguishing among groups. At the univariate level, it was found that VS patients displayed reduced connectivity in most thalamo‐cortical circuits of interest, including frontal, temporal, and sensorimotor connections, as compared with MCS+, but showed more pulvinar‐occipital connections when compared with MCS−. Moreover, MCS− exhibited significantly less thalamo‐premotor and thalamo‐temporal connectivity than MCS+. At the multivariate level, it was found that thalamic tracks reaching frontal, parietal, and sensorimotor regions, could discriminate, up to 100% accuracy, across each pairwise group comparison. Together, these findings highlight the role of thalamo‐cortical connections in patients' behavioral profile and level of consciousness. Diffusion tensor imaging combined with machine learning algorithms could thus potentially facilitate diagnostic distinctions in DOC and shed light on the neural correlates of consciousness. Hum Brain Mapp 38:431–443, 2017. © 2016 Wiley Periodicals, Inc.
A Representative Application of a Layered Interface Modeling Pattern
Authors: Shames Peter M. , Sarrel Marc A. , Friedenthal Sanford 
Published: September 2016

AbstractModel‐based systems engineering (MBSE) is intended to improve how systems engineering is performed compared with a more traditional document‐based approach by effectively using models to analyze, specify, design, and verify systems. The OMG Systems Modeling Language (OMG SysML™) enables the practice of MBSE by providing a robust and expressive language for representing systems.Several MBSE methods are available [3], and have continued to mature over the last several years which include model‐based practices for requirements flow‐down, architecture‐design, trade‐off analysis, verification planning, and others. One of the critical systems engineering practices is interface modeling. This paper describes a layered interface pattern for modeling data and communications interfaces using SysML. The pattern spans logical to physical interface definition, and includes software and electrical interfaces.Each layer in a stack describes a portion of the interface functionality. The concept of a layered interface is borrowed from computer networking [8] [10]. The layered interface pattern described in this paper enables the specification and design of connections and behavior between interfacing systems at a given layer, and between the adjacent layers of a single system. This pattern may also be applied recursively. That is, communication within a single layer may itself be realized by a multi‐layer stack. The level of detail of the model to describe a layered interface should be adapted to the need, and can vary from highly abstract logical flows across a system to highly detailed protocol specifications and message structures.This paper builds on work that was documented in a previous paper entitled “A modeling pattern for layered system interfaces” [5]. Aspects of this pattern have been demonstrated in various project applications including Exploration Flight Test 1 (EFT‐1), Space Communication and Navigation (SCaN) Trade Studies, and the SCaN Network Integration Project (SNIP).
Systems Engineering for a Circular Economy
Authors: Falk Daniel , Steiber Bengt‐Göran 
Published: September 2016

AbstractThis paper identifies and describes the principles of circular economy that is getting increased attention in Europe. In 2012 the Ellen MacArthur Foundation, in cooperation with industrial partners, presented a financial report outlining the economic potential inherent in the products of today. With a change in mindset and the use of different business models this potential of $630bn, in Europe alone, can be extracted.This paper discusses the effects of a circular approach and the impact the required shift in business models will have on the fundamental ideas and concepts of today's enterprises. Furthermore the paper states that many of the methods and tools required to perform this change are already accessible today within the systems engineering and logistics engineering domains. The new business models used in a circular economy will require an enhanced integration of these two domains.
Simplifying (and enriching) SysML to perform functional analysis and model instances
Authors: Voirin Jean‐Luc , Bonnet Stéphane , Exertier Daniel , Normand Véronique 
Published: September 2016

AbstractConfronted with real life and full‐scale operational deployment, model‐based engineering languages and tools may fail to address the wide variety of practices situations can require. This paper describes issues encountered with SysML in the context of systems architectural design. It gives an overview of the adapted language and practices that form the foundations of Arcadia and Capella, a field‐proven model‐based engineering method and its associated open source workbench. Relying on concrete examples, this paper focuses on modeling constructs supporting functional analysis and addresses the problematics of modeling at instance level.
Issues in Conceptual Design and MBSE Successes: Insights from the Model‐Based Conceptual Design Surveys
Authors: Morris Brett A. , Harvey David , Robinson Kevin P. , Cook Stephen C. 
Published: September 2016

AbstractThe INCOSE Model‐Based Conceptual Design (MBCD) Working Group was established in 2011 with the purpose of advancing the body of knowledge and practice of systems engineering (SE), through the development and application of model‐based systems engineering (MBSE) methodologies to the concept stage of a system's life‐cycle. The Working Group strives to achieve its vision through a series of activities conducted by members of the working group. One of these activities was to conduct a survey of people involved in MBCD, with the goal: To identify the issues associated with performing Conceptual Design and areas where MBCD has been successful. As part of this activity, two surveys, one in 2014 and one during 2015, have been conducted. This paper begins with an overview of the first survey and the need for a second survey that arose from the possibility of non‐response bias being present in the first survey's results. Following this, the results obtained from the second survey are presented, compared with the results from the first survey and discussed. The key insights the authors uncovered from the results, survey workshops, and symposium presentations on both surveys are also identified. The paper concludes with a discussion on how these results are being used to inform current MBCD WG activities and strategic planning.
Systems Engineering a Model Based Systems Engineering Tool Suite: The Boeing Approach
Authors: Friedland Brittany , Malone Robert , Herrold John 
Published: September 2016

AbstractGiven the scope of some of the large scale system architecture models created at The Boeing Company, it is currently necessary for Boeing to customize its own Model Based Systems Engineering (MBSE) tool suites from Commercial‐Off‐The‐Shelf (COTS) platforms to accommodate these models. Boeing successfully applies a modified set of Systems Engineering (SE) architectures to specify the required MBSE tool suites and also has developed a unique SE skill set for engineers creating these specifications and developing and deploying the subsequent tool suites. Furthermore, Boeing uses an MBSE tool suite to create these tool suite specifications as models, and also manages the configuration of the MBSE tool suite within the models.
On System Dynamics Modeling of Human‐Intensive Workflow Improvement – Case Study in Cybersecurity Adaptive Knowledge Encoding
Authors: Willett Keith D. , Dove Rick , Cloutier Robert , Blackburn Mark 
Published: September 2016

AbstractModeling and simulation offers one way to express a system of systems, to measure its performance, and predict the effects of prospective modifications. This paper introduces a system dynamics model (SDM) as a systems engineering design decision support tool. The SDM structure, design rationale, and results have broader applicability to many people‐oriented workflows that may benefit from 1) working smarter and 2) introducing automation to complement human activities. The SDM structure consists of a sequential time‐essential workflow of eleven phases. The simulation establishes a pre‐modification performance baseline, identifies the fit of a prospective modification with intent to improve workflow, estimates the modification's effect on performance, and then produces post‐modification performance results to compare with the baseline. To provide focus for the SDM, the details herein use cybersecurity operations as one example of a system of systems predominantly operated by people performing insufficiently to address the volume of cyberspace‐related anomalies. The SDM is specifically for cybersecurity operations to identify procedural bottlenecks and show the impact of proposed improvements. Cybersecurity decision patterns (CDPs) provide a case study as a prospective improvement. CDPs are one solution under the integrated adaptive cyberspace defense – joint cognitive system capability area to help establish and sustain agile cybersecurity operations (Willett 2015a). Lessons learned from the approach, application, and results are more broadly applicable to many systems and system of systems operations.
Getting Started with MBSE in Product Development
Authors: Kass Nichole , Kolozs James 
Published: September 2016

AbstractWhether it is a small company hoping to start using systems engineering with a Model Based Systems Engineering (MBSE) approach, or a larger, established company interested in converting existing document‐based practices to MBSE, the challenges can be daunting. These can include unfamiliarity with the MBSE tool, complex default schemas, and understanding what is worth tracking in MBSE (or not). This paper will address the practical aspects for building and using a simplified MBSE schema. The schema details a selection of diagrams and items to be used for each phase of the product development process. The practical aspects for what information to include, how to trace items to each other, and what to include in each output document are described and demonstrated with examples.
Insights from Large Scale Model Based Systems Engineering at Boeing
Authors: Malone Robert , Friedland Brittany , Herrold John , Fogarty Daniel 
Published: September 2016

AbstractDevelopment and design of increasingly integrated aerospace systems, by globally distributed engineering teams, presents challenges in bounding the effort required to produce, integrate, manage and validate the large and detailed accompanying specification datasets. Model Based Systems Engineering has become essential in allowing Boeing to meet these challenges. Through verification and validation of sufficiently detailed large scale system architecture models, Boeing has been successful in accelerating data release schedules, while at the same time eliminating specification errors that result in costly rework. In the process of developing these large scale system architecture models, Boeing has acquired some insights into what is required to effectively develop, deploy and manage an MBSE environment, and these insights are detailed in this paper. Additionally, recommendations are made as to how standards organization, the MBSE tool industry, and academia could better support the MBSE community.
A Case for Product Lines
Authors: Nolan Andy J. , Pickard Andrew C. , Fisher Steve , Beasley Richard 
Published: September 2016

AbstractIt would seem obvious that a business could benefit from a Product Line, but what is the business case, when can we expect benefits and how much do we need to invest? Under what conditions will it not be cost beneficial to adopt a Product Line?A Product Line is complicated, strategic in nature and it is probably beyond the capability of most people to simply “judge” if it is the right strategy. It was evident that in order for Rolls‐Royce to understand Product Lines, and to make the right trade decisions, we would need to develop a Product Line cost/benefit estimation tool. The tool estimated both the costs to develop assets as well as the costs to deploy the assets onto a project.This paper summarizes the estimation tool we developed and some of the conclusions it revealed. Although the concept was used on a Software Product Line, the principles have been duplicated in hardware and Systems Engineering but are not discussed in this paper.
It Takes a Village: Why PLE Technology Solutions Require Ecosystems of PLE Technology Providers
Authors: Bolander William J. , Clements Paul C. , Krueger Charles 
Published: September 2016

AbstractIn product lines with many products and demanding production tempos, manual product derivation is simply not feasible, which leaves us with the option of automated product derivation. That is easily enough said, but what precisely is the role of that automation? While commercially available PLE product production tools are available (usually called configurators), they cannot by themselves provide a complete engineering solution to a product line organization. Instead, an ecosystem of tooling is required. This paper explores what capabilities a PLE tool needs to have, why other tools are necessary as part of a holistic PLE technology solution, and what roles that other tooling must play.
Systems Engineering and Critical Reflection: The Application of Brookfield and Goffman to the Common Experiences of Systems Engineers
Authors: Madhav Chucks 
Published: September 2016

AbstractCritical reflection is the process of evaluating our assumptions to come to a better and clearer understanding of ourselves, our systems engineering work, and our environment. With critical reflection, not only are we better able to navigate a path towards success but it allows us to recognize our contribution and effort towards our professional development. A critically reflective systems engineer is also better able to navigate the risks, challenges, and setbacks of systems engineering. Critical reflection allows us to learn from our experiences and to realize these experiences are not unique but part of the common and expected set of experiences. The language of critical reflection provides a foundation to better know ourselves and become more effective systems engineers.This paper explores the concept of critical reflection, how it applies to systems engineers, the advantages to conducting critical reflection, and the benefits to our businesses.
Building a Technical Leadership Model
Authors: Godfrey Patrick 
Published: September 2016

AbstractINCOSE's Vision 2025 identifies the development of Systems Thinking and Technical Leadership as one of seven key areas of Systems Engineering ‘Competency’ required for delivery. Vision 2025 states: “Education and training of systems engineers and the infusion of systems thinking across a broad range of the engineering and management workforce will meet the demands for a growing number of systems engineers with the necessary technical and leadership competencies.” “The roles and competencies of the systems engineer will broaden to address the increasing complexity and diversity of future systems.” “The technical leadership role of the systems engineer on a project will be well established as critical to the success of a project.” These requirements imply the need to rapidly expand the art and science of Systems Technical Leadership. In response to this need, INCOSE established the INCOSE Institute for Technical Leadership. This paper describes the Institute and the work that the first Cohort (“Cohort of 2017”) has accomplished on developing a Technical Leadership Model for Systems Engineers. It is envisaged that this first Technical Leadership Model for Systems Engineers will be further developed and matured by the following cohorts of the INCOSE's Technical Leadership Institute.