bluuebunny/crossref_metadata_2025_split huggingface dataset:
Using Set‐Based Design to Inform System Requirements and Evaluate Design Decisions
Authors: Parnell Gregory S. , Specking Eric , Goerger Simon , Cilli Matthew , Pohl Edward 
Published: September 2019

AbstractSet‐Based Design (SBD) is a concurrent engineering technique for system design and systems analysis and an alternative to Point‐Based Design (PBD). System analysts perform Tradespace Exploration in early system design to assess requirements and identify affordable designs that meet complex stakeholder requirements. This paper demonstrates the use of SBD to inform system requirements and evaluate design options. We use an Unmanned Aerial Vehicle (UAV) case study with an integrated Model‐Based Engineering framework with SBD to identify potential designs, assess design feasibility, inform requirements, and evaluate feasible designs displayed in sets with common design choices. We use SIP Math from Probability Management© to explore 100,000 potential systems design concepts and architectures in near real‐time. Using our integrated framework with 47 physics‐based models and 11 requirements, we found that only 2.5% of the potential designs were feasible. We validate that SBD finds the efficient frontier in the value versus cost tradespace. We use SBD to inform systems requirements by identifying the number of potential feasible designs in the tradespace for each requirement or combination of requirements. Relaxing the requirements can increase the percentage of feasible designs. Constraining or relaxing 4 of the 11 requirements significantly affected the feasible design space. We also use SBD to evaluate design options, which provides useful information for system designers. We conclude that SBD provides a more comprehensive tradespace exploration than PBD and useful insights into requirement development.
Systems Engineering: Transforming Digital Transformation
Authors: Peterson Troy A. 
Published: September 2019

AbstractWhile complex systems transform the landscape, the Systems Engineering discipline is also experiencing a transformation to a model‐based discipline. In alignment with this, one of the International Council on Systems Engineering (INCOSE) strategic objectives is to accelerate this transformation. INCOSE is building a broad community that promotes and advances model‐based methods to manage the complexity of systems which seamlessly integrate computational algorithms and physical components across domains and traditional boundaries. This paper addresses contextual drivers for transformation as well as obstacles, enablers, and INCOSE re‐sources aligned with accelerating the transformation of Systems Engineering to a model‐based discipline.
An Approach for Formal Verification of Machine Learning based Complex Systems
Authors: Raman Ramakrishnan , Jeppu Yogananda 
Published: September 2019

AbstractA complex system is characterized by emergence of global properties which are very difficult, if not impossible, to anticipate just from complete knowledge of component behaviors. Emergence, hierarchical organization and numerosity are some of the characteristics of complex systems. With increasing system complexity, achieving confidence in systems becomes increasingly difficult. With the recent trend towards significant footprint of complex system's functionality being governed by machine learning based models and algorithms, there is a need to ensure that emergent behavior associated with such systems are well analyzed and understood. Traditional verification and validation approaches are often inadequate to bring in the nuances of potential emergent behavior, which may be positive or negative. This paper describes a novel approach towards application of formal methods for analyzing and evaluating emergent behavior of complex systems that are governed by machine learning models. The proposed approach involves developing a machine learning classifier model that learns on potential negative and positive emergent behaviors, and leveraging the classifier in a formal verification model checking environment to assert negative emergent behavior. The approach is illustrated through an example of a pitch control system of an aircraft. The effectiveness and performance of the approach are quantified.
12 principles for SE leaders
Authors: Kemp Duncan , O'Neil Meaghan 
Published: September 2019

AbstractThis paper describes 12 leadership principles to follow when building an Systems Engineering (SE) Capability.Successful Systems Engineering leadership requires the fusion of systems engineering and leadership. Based upon the authors' experience in Defence, Rail, Information Services, Healthcare, Medical Devices, Power and Manufacturing, this paper describes practical approaches to:
Make and sustain the case for SE. Ensure that SE contributes to the business and that it is supported by key stakeholders.
Establish the right culture and provide a supportive environment within which systems engineers can deliver.
Select the right approach to deliver SE, decide whether to invest in an in‐house capability and decide how to deploy systems engineers
Align the SE processes to the wider business.
Grow an effective SE team. Select the right people, balance of technical and interpersonal competencies and grow the team as the business need grows.
Select appropriate methods and tools.
Can We Use Wisdom‐of‐the‐Crowd to Assess Risk of Systems Engineering Failures?
Authors: Georgalis Georgios , Marais Karen 
Published: September 2019

AbstractDespite advances in project risk assessment methods, systems engineering failures like cost overruns, schedule slips, and failure to meet technical requirements continue to occur with high frequency. Wisdom‐of‐the‐Crowd (WoC) signals from inside the project team can complement expert management experience for risk assessment and help reduce such failures. We consider three metrics of project risk: budget, schedule and technical performance and evaluate whether WoC can provide correct estimates of these three metrics. We present a crowd‐based method to collect qualitative estimates of project metrics from engineering student teams and predict the probability that these estimates are correct. We investigate whether a team‐centered WoC approach provides better estimates than an individual‐centered case. We conclude that the WoC approach provides on average more accurate budget estimates than the individual‐centered approach. For estimating project schedule and technical performance, the WoC approach performs better when the estimate comes from individuals with high confidence.
Frenemies: OPM and SysML Together in an MBSE Model
Authors: Hause Matthew C. , Day Robert L. 
Published: September 2019

AbstractA Frenemy is “a person with whom one is friendly despite a fundamental dislike or rivalry.” (OED, 2018). The Systems Modeling Language (SysML) and the Object Process Methodology (OPM) are two such frenemies. OPM and SysML are different means of achieving Model‐Based Systems Engineering (MBSE), each with their own benefits, issues, supporters and detractors. The National Defense Industry Association (NDIA) defines MBSE as “an approach to engineering that uses models as an integral part of the technical baseline that includes the requirements, analysis, design, implementation, and verification of a capability, system, and/or product throughout the acquisition life cycle.” (NDIA, 2011) SysML is based on the Unified Modeling Language (UML) and includes diagrams that can be used to specify system requirements, behavior, structure and parametric relationships. SysML provides a means of defining high‐level abstract systems down to detailed physical systems. OPM is a “conceptual modeling language and methodology for capturing knowledge and designing systems. Based on a minimal universal ontology of stateful objects and processes that transform them, OPM can be used to formally specify the function, structure, and behavior of artificial and natural systems in a large variety of domains.” (ISO, 2015) OPM is used in some systems engineering graduate courses. Students graduating from these institutions are struggling to integrate the differing styles, philosophies, concepts and processes of SysML and OPM. A literature search reveals some papers that contrast SysML and OPM, but none that describe how the two can work together. This paper discusses a synergy of SysML and OPM in a SysML tool rather than promoting one language over another.
Experience from a Program for Accelerating the Creation of T‐shaped Technical Leaders
Authors: Cederberg Linda , Axehill Johanna Wallén , Herzog Erik 
Published: September 2019

AbstractIn the aerospace industry systems are becoming more and more complex. At the same time development projects run for longer time periods. Consequently there are fewer opportunities for engineers to experience the full system lifecycle and the associated nuances in development. This in turn makes it more challenging to grow staff suitable for technical leadership roles, including both breadth and depth of technical skills as well as soft skills for leading large engineering projects.In this paper we examine the desired competencies of a technical leader by extending the T‐shape engineer model and use the said model to discuss an organization internal, 2.5 year, program to accelerate the creation of technical leaders. The evaluation is performed through interviews with program participants and organizational internal stakeholders. Overall the program has proven cost efficient and successful in the sense the program participants in many cases have progressed into technical leadership roles. The program, as described, has been executed within a single organization but should be feasible to execute in other organizational settings. While results are very positive, there are some identified improvement suggestions included in the analysis of the program.
A System Dynamics Model for Systems Security Engineering Analysis of Internet Service Provider Customer Modem Cyber Defense
Authors: Eason David K. , Gelosh Don S. 
Published: September 2019

AbstractInternet service providers seek to increase revenue by reducing costs and increasing subscriptions. We take a systems security engineering approach to evaluate ways of enhancing customer modem cybersecurity, using a system dynamics model to show the impact of different solutions for improving customer modem bandwidth. The model is extensible and modifiable to test other stakeholder goals. We demonstrate this by modelling customer goodwill and solution cost. When used as a tool for planning system changes, the model can be compared to the live system before and during incremental system changes. This helps improve model validity, control risk, evaluate return on investment, and provide a platform for testing proposed system changes. Businesses with similar cyber vulnerabilities can benefit from using this system engineering approach.
Graph‐based Assessment and Analysis of System Architecture Models
Authors: Petnga Leonard 
Published: September 2019

AbstractWe conceptualize, develop and prototype a semi‐automatic graph‐based framework for quality assessment (i.e., completeness, consistency, correctness) and probing — at all stages of development and maturity — architecture models developed in the System Modeling Language (SysML). Relevant data is extracted via partial model transformation, then organized and stored in a labeled property graph. Analytics powered by graph algorithms enable the System Analyst to gain deep insight into the model and answer increasingly complex and diverse questions. Multidigraph formalisms provide solid theoretical foundations for our approach while graph database technologies coupled with custom software development support its implementation. We demonstrate the capability of our approach in an analysis of requirements in a publicly available spacecraft architecture model.
A3 Architecture Views – A Project Management Tool?
Authors: Boge Tore , Falk Kristin 
Published: September 2019

AbstractThis paper explores the benefits of using A3 Architecture Overviews (A3AO) as a tool for project management and interdisciplinary knowledge sharing in a development project. The goal of the development project was to create an autonomous subsea inspection systems for the oil and gas industry. Sharing of implicit system knowledge early in the systems life cycle is a challenge, yet important for successful development of new technology. Through expert interviews and reverse architecting we made A3AO for two new system that were sequential steps into a fully autonomous solution. Through the research we applied these overviews in meetings with HSEQ, finance, senior management, and engineering. The immediate responses were positive, with comments like, “now I understand what we are trying to achieve”, and “Can I please include the A3AO in my document for the management?” Project personnel, with limited system knowledge, quickly got an enhanced understanding of the project goals by viewing the A3AO. We also experienced that senior management used the illustrative tool as a supplement to support a business case for the board of directors. Clients were happy to see models and schematics as a supplement to textural documents when being presented with new technology. Inclusion of industry terminology and support from management would enhance adoption of A3AO within the oil and gas industry. Overall, our research strongly supports the use of A3 Architectural Overviews as a project management tool when developing new complex systems.
Exploring the Test and Evaluation Space using Model Based Conceptual Design (MBCD) Techniques
Authors: Flanigan David , Robinson Kevin 
Published: September 2019

AbstractDuring the initial concept development phase, systems engineers focus on defining the problem space and system functions in order to explore candidate concepts that may address the systems engineers' problems. Model Based Conceptual Design (MBCD) techniques may be used to assist the customer and other stakeholders develop a greater understanding of the system concept, as well as identifying areas in the system that are affected by changes in requirements. This approach has generally been documented for describing the system concept in the early stages in the lifecycle, without significant focus on the Test and Evaluation (T&E) space that would be needed to evaluate these concepts, or identifying where the T&E space would be affected with a change in requirements. Our hypothesis is that decision makers would equally gain insight into the T&E considerations as well as system space considerations using MBCD techniques. An approach is offered to extend the previously published MBCD methodology to better consider the T&E space.
The Need for an Information‐based Approach for Requirement Development and Management
Authors: Wheatcraft Lou , Ryan Mike , Llorens Juan , Dick Jeremy 
Published: September 2019

AbstractIn many organizations, the quality of the individual requirement statements and sets of requirements is often poor, not having the characteristics of well‐formed requirement statements and sets of requirements. Correctness, completeness, consistency, ambiguity, feasibility, implementation, leveling, etc. are common issues. This puts a heavy burden on the design team to address and correct these issues. Given these issues, it is common for modern systems engineers to even question the need for text‐based requirements. This paper discusses why text‐based requirements are still important, their role in the overall systems engineering lifecycle activities, and identifies key issues in the current approach many organizations practice concerning requirement development and management (RDM) – especially how RDM relates to current model‐based design and systems engineering approaches.
Fumonisin B1 damages the barrier functions of porcine intestinal epithelial cells in vitro
Authors: Chen Zhigang , Chen Huiyu , Li Xue , Yuan Qiaoling , Su Jianming , Yang Lei , Ning Lingzhong , Lei Hongyu 
Published: September 2019

AbstractFumonisins (Fums) are mycotoxins widely distributed in crops and feed, and ingestion of Fums‐contaminated crops is harmful to animal health. The purpose of this study is to explore the effect of Fum B1 (FB1) on barrier functions of porcine intestinal epithelial cells, IPEC‐J2, to clarify the intestinal toxicity of Fums in pigs. The results showed that the persistent treatment of FB1 significantly decreased the viability of IPEC‐J2. Moreover, the expressions of Claudin 1, Occludin, Zonula Occluden‐1 (ZO‐1) on the messenger RNA (mRNA), and protein levels and MUC1 on the mRNA level were significantly inhibited after FB1 treatment, while the mRNA relative expression level of MUC2 was clearly increased. FB1 also enhanced the monolayer cell permeability of IPEC‐J2. Importantly, FB1 promoted the expression of phosphorylated extracellular regulated protein kinase (p‐ERK1/2). These data suggest that long‐term treatment of FB1 can suppress IPEC‐J2 proliferation, damage tight junctions of IPEC‐J2, and regulate expression of mucins to induce the damage of barrier functions of porcine intestinal epithelial cells, which may be associated with the ERK1/2 phosphorylation pathway.
Polyinosinic‐polycytidylic acid accelerates intestinal stem cell proliferation via modulating Myc expression
Authors: Zeng Huihong , Tang Jiahui , Yue Mengzhen , Cheng Jiaoqi , Fan Ying , Li Manjun , Zhang Xinxin , Li Huan , Duan Hongyi , Zhang Minqing , Fan Guangqin , Zhu Qingxian , Shao Lijian 
Published: September 2019

AbstractIt is well known that exposure of double‐stranded RNA (dsRNA) to intestine immediately induces villus damage with severe diarrhea, which is mediated by toll‐like receptor 3 signaling activation. However, the role of intestinal stem cells (ISCs) remains obscure during the pathology. In the present study, polyinosinic‐polycytidylic acid (poly[I:C]), mimicking viral dsRNA, was used to establish intestinal damage model. Mice were acutely and chronically exposed to poly(I:C), and ISCs in jejunum were analyzed. The results showed that the height of villus was shorter 48 hr after acute poly(I:C) exposure compared with that of controls, while chronic poly(I:C) treatment increased both villus height and crypt depth in jejunum compared with control animals. The numbers of ISCs in jejunum were significantly increased after acute and chronic poly(I:C) exposure. Poly (I:C)‐stimulated ISCs have stronger capacities to differentiate into intestine endocrine cells. Mechanistically, poly(I:C) treatment increased expression of Stat1 and Axin2 in the intestinal crypt, which was along with increased expression of Myc, Bcl2, and ISC proliferation. These findings suggest that dsRNA exposure could induce ISC proliferation to ameliorate dsRNA‐induced intestinal injury.
Differential expression of inflammasome regulatory transcripts in periodontal disease
Authors: Aral Kübra , Berdeli Eynar , Cooper Paul Roy , Milward Michael Robert , Kapila Yvonne , Karadede Ünal Beyza , Aral Cüneyt Asım , Berdeli Afig 
Published: September 2019

AbstractBackgroundThe inflammasome modulates the release of key proinflammatory cytokines associated with periodontal disease pathogenesis. The aim of this study was to evaluate the expression of proteins that regulate the inflammasome, namely pyrin domain‐only proteins (POPs), caspase activation recruitment domain (CARD)‐only proteins, and tripartite motif‐containing (TRIM) proteins, in periodontal diseases.MethodsA total of 68 participants (34 males and 34 females) were divided into four groups, including periodontal health (H), gingivitis (G), chronic periodontitis (CP), and aggressive periodontitis (AgP) based on clinical parameters. Gingival tissue samples were obtained from all participants for reverse transcription polymerase chain reaction (RT‐PCR)‐based gene expression analyses of molecules that regulate the inflammasome, including apoptosis‐associated speck‐like protein (ASC) containing CARD, caspase‐1, interleukin‐1β (IL‐1β), interleukin‐18 (IL‐18), nucleotide‐binding domain, leucine rich family (NLR) pyrin domain containing 3 (NLRP3), NLR family pyrin domain containing 2 (NLRP2), AIM2 (absent in melanoma 2), POP1, POP2, CARD16, CARD18, TRIM16, and TRIM20 by RT‐PCR.ResultsNLRP3 and IL‐1β were upregulated in the G, CP, and AgP groups compared with group H (P < 0.05). AIM2 was downregulated in the CP group compared with the H, G, and AgP groups (P < 0.05). TRIM20, TRIM16, and CARD18 were downregulated in the G, CP, and AgP groups compared with the H group (P < 0.05). POP1 and POP2 were downregulated in the CP and AgP, and AgP and G groups, respectively (P < 0.05).ConclusionActive periodontal disease may result in downregulation of inflammasome regulators that may increase the activity of NLRP3 and IL‐1β in periodontal disease.
Enhanced Temperature Stability of High Energy Density Ferroelectric Polymer Blends: The Spatial Confinement Effect
Authors: Liu Yongbin , Gao Jinghui , Wang Yan , Zhou Jun , Cao Liang , He Zhixin , Zhang Yang , Tang Chao , Zhong Lisheng 
Published: September 2019

AbstractThermal stability of polymer structure is a key to achieve stable energy density at elevated temperature for ferroelectric‐polymer‐based capacitors. Here, a poly (vinylidene fluoride) / polymethyl methacrylate (PMMA) blend with a stabilized spherulite structure displaying steady energy density around 7.8–9.8 J cm−3 across the temperature range up to 70 °C is reported, which outperforms most neat ferroelectric polymers at elevated temperature. The microstructure of the blend observed by atomic force microscopy exhibits an alternating lamellar structure (crystalline/mixed amorphous layers) within spherulites, which might be rationalized by PMMA being gradually expelled from the spherulite and finally staying between PVDF lamellae during crystallization. The structure with rigid amorphous layers can induce a spatial confinement effect of chain motion and structural change under thermal stress, which is evidenced by temperature‐insensitive long period in small‐angle X‐ray scattering measurements. The enhanced thermal stability of energy storage can be attributed to the constraint on free volume and carrier transportation caused by the spatial confinement. Our findings provide a strategy to attain temperature‐stable high‐energy‐density ferroelectric polymers for energy storage capacitors.
Sensitivity analysis on responsive pricing and production under imperfect demand updating
Authors: Chua Geoffrey A. , Liu Yan 
Published: September 2019

AbstractThis paper examines three types of sensitivity analysis on a firm's responsive pricing and responsive production strategies under imperfect demand updating. Demand has a multiplicative form where the market size updates according to a bivariate normal model. First, we show that both responsive production and responsive pricing resemble the classical pricing newsvendor with posterior demand uncertainty in terms of the optimal performance and first‐stage decision. Second, we show that the performance of responsive production is sensitive to the first‐stage decision, but responsive pricing is insensitive. This suggests that a “posterior rationale” (ie, using the optimal production decision from the classical pricing newsvendor with expected posterior uncertainty) allows a simple and near‐optimal first‐stage production heuristic for responsive pricing. However, responsive production obtains higher expected profits than responsive pricing under certain conditions. This implies that the firm's ability to calculate the first‐stage decision correctly can help determine which responsive strategy to use. Lastly, we find that the firm's performance is not sensitive to the parameter uncertainty coming from the market size, total uncertainty level and information quality, but is sensitive to uncertainty originating from the procurement cost and price‐elasticity.