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The curation of ontologies and knowledge graphs (KGs) is an essential task for industrial knowledge-based applications, as they rely on the contained knowledge to be correct and error-free. Often, a significant amount of a KG is curated by humans. Established validation methods, such as Shapes Constraint Language, Shape Expressions or Web Ontology Language, can detect wrong statements only after their materialization, which can be too late. Instead, an approach that avoids errors and adequately supports users is required.

For solving that problem, Property Assertion Constraints (PACs) have been developed. PACs extend the range definition of a property with additional logic expressed with SPARQL. For the context of a given instance and property, a tailored PAC query is dynamically built and triggered on the KG. It can determine all values that will result in valid property value assertions.

PACs can avoid the expansion of KGs with invalid property value assertions effectively, as their contained expertise narrows down the valid options a user can choose from. This simplifies the knowledge curation and, most notably, relieves users or machines from knowing and applying this expertise, but instead enables a computer to take care of it.

PACs are fundamentally different from existing approaches. Instead of detecting erroneous materialized facts, they can determine all semantically correct assertions before materializing them. This avoids invalid property value assertions and provides users an informed, purposeful assistance. To the author's knowledge, PACs are the only such approach.

The 1998 International Federation of Library Associations (IFLA) document “Functional Requirements for Bibliographic Records” (FRBR) has inspired a family of models that view bibliographic resources in terms of multiple entities differentiated with regard to meaning, expression, and physicality. The purpose of this paper is to compare how three FRBR and FRBR-like models have been expressed as Semantic Web vocabularies based on Resource Description Framework (RDF). The paper focusses on IFLA’s own vocabulary for FRBR; RDF vocabularies for Resource Description and Access (RDA), an emergent FRBR-based standard for library cataloging; and BIBFRAME, an emergent FRBR-like, native-RDF standard for bibliographic data.

Simple test records using the RDF vocabularies were analyzed using software that supports inferencing.

In some cases, what the data actually means appears to differ from what the vocabulary developers presumably intended to mean. Data based on the FRBR vocabulary appears particularly difficult to integrate with data based on different models.

Some of the RDF vocabularies reviewed in the paper could usefully be simplified, enabling libraries to integrate their data more easily into the wider information ecosystem on the Web. Requirements for data consistency and quality control could be met by emergent standards of the World Wide Web Consortium for validating RDF data according to integrity constraints.

There are few such comparisons of the RDF expressions of these models, which are widely assumed to represent the future of library cataloging.

Economic conditions such as convexity, homogeneity, homotheticity, and monotonicity are all important assumptions or consequences of assumptions of economic functionals to be estimated. Recent research has seen a renewed interest in imposing constraints in nonparametric regression. We survey the available methods in the literature, discuss the challenges that present themselves when empirically implementing these methods, and extend an existing method to handle general nonlinear constraints. A heuristic discussion on the empirical implementation for methods that use sequential quadratic programming is provided for the reader, and simulated and empirical evidence on the distinction between constrained and unconstrained nonparametric regression surfaces is covered.

Over the past few years, business‐to‐business (B2B) e‐commerce has grown exponentially. To conduct B2B e‐commerce, companies need a common language. HTML is not suited for this task, because it defines only the information’s format instead of its meaning. XML has been shown to not only be the most natural evolution of Web technologies to support modern applications such as e‐commerce, but also be the preferred means of making legacy data available to users via the Internet. Since XML is still in its infancy, early versions of XML do not include the fundamental feature of specifying and enforcing integrity constraints, which is critical to making XML a viable and long‐term approach for representing data over the Web. In other words, XML provides little support to make sure the data being represented satisfy the business rules specified. Reviews the trends in B2B e‐commerce and discusses the critical needs to support constraints and the integrity of data, which are very important to the success of B2B e‐commerce. Also presents the next generation of XML technology for representing constraints. Concludes with a summary of the impact of the new XML on B2B e‐commerce and its future challenges.

The purpose of this paper is to compare the use of two Object-Relational models against the use of a post-Relational model for a realistic application. Although real-world applications, in most cases, can be adequately modeled by the Entity-Relationship (ER) model, the transformation to the popular Relational model alters the representation of structures common in reality, like multi-valued and composite fields. Alternative database models have been developed to overcome these shortcomings.

Based on the ER model of a medical application, this paper compares the information representation, manipulation and enforcement of integrity constraints through PostgreSQL and Oracle, against the use of a post-Relational model composed of the Conceptual Universal Database Language (CUDL) and the Conceptual Universal Database Language Abstraction Level (CAL).

The CAL/CUDL pair, although more periphrastic for data definition, is simpler for data insertions, does not require the use of procedural code for data updates, produces clearer output for retrieval of attributes, can accomplish retrieval of rows based on conditions that address composite data with declarative statements and supports data validation for relationships between composite data without the need for procedural code.

To verify, in practice, the conclusions of the paper, complete implementation of a CAL/CUDL system is needed.

The use of the CAL/CUDL pair would advance the productivity of database application development.

This paper highlights the properties of realistic database-applications modelling and management that are desirable by developers and shows that these properties are better satisfied by the CAL/CUDL pair.

The purpose of this study is to develop an index for financial constraints, specifically for restaurant firms, and to further validate the developed financial constraint index.

This study used logistic regression with a composite criterion based on the dividend payout ratio, KZ index and Cleary index to estimate restaurant firms’ financial constraints. Then, a fixed-effects regression was used to verify the validity of the measurement of restaurant firms’ financial constraints.

A restaurant firm’s operating profit, financial leverage, asset tangibility, sale of fixed assets and percentage change in number of employees are critical indicators for identifying financial constraints. The results indicated that in cases with positive operating cash flows, the effect of operating cash flow on capital investments continuously decreased as restaurant firms’ financial constraints increased.

This study is unique in that the specific financial and operational characteristics of restaurant firms were included in the model to determine financial constraint indicators, such as sale of fixed assets and percentage change in number of employees.

As the world is becoming more volatile and uncertain, organizations face much complexity in their daily operations. Further, there is a much ambiguity in business operations to achieve the effective utilization of resources. The work optimizes a novel constraint programming model approach of the utilization of shuttle services vehicle while considering cost savings, employee wellbeing and other real an Information Technology enabled service (ITES) industry constraints.

The present work considers a novel extension of the vehicle routing problem related to the shuttle service operation in an ITES industry in VUCA context. Additionally, the model considers the women safety aspects, which engages the company to provide a security guard for women employees in the night shift.

Numerical experiments were conducted on real instances data of ITES industrial partner. The results show that the vehicle utilization increased from 75% up to 96% while ensuring in parallel the wellbeing of employees and women safety during the night shift. Finally, the proposed model is converted to a decision support application allowing ITES partner to plan employees shuttle service operations efficiently.

Study has evaluated the shuttle services optimization for ITES industry using data from industrial which makes it a unique contribution to literature in shuttle operations. Further, the study used constraint programming to evaluate the vehicle utilization and security allocation, thereby introducing new parameter on security allocation in open VRP problem.

In the vast majority of the individual robot installations, the robot arm is just one piece of a complex puzzle of components, such as grippers, jigs or external axis, that together compose an industrial robotic cell. The success of such installations is very dependent not only on the selection of such components but also on the layout and design of the final robotic cell, which are the main tasks of the system integrators. Consequently, successful robot installations are often empirical tasks owing to the high number of experimental combinations that could lead to exhaustive and time-consuming testing approaches.

A newly developed optimized technique to deal with automatic planning and design of robotic systems is proposed and tested in this paper.

The application of a genetic-based algorithm achieved optimal results in short time frames and improved the design of robotic work cells. Here, the authors show that a multi-layer optimization approach, which can be validated using a robotic tool, is able to help with the design of robotic systems.

The usage of the proposed approach can be valuable to industrial corporations, as it allows for improved workflows, maximization of available robotic operations and improvement of efficiency.

To date, robotic solutions lack flexibility to cope with the demanding industrial environments. The results presented here formalize a new flexible and modular approach, which can provide optimal solutions throughout the different stages of design and execution control of any work cell.

The purpose of this paper is to provide a feature‐based characterization of version control systems (VCSs), providing an overview about the state‐of‐the‐art of versioning systems dedicated to modeling artifacts.

Based on a literature study of existing approaches, a description of the features of versioning systems is established. Special focus is set on three‐way merging which is an integral component of optimistic versioning. This characterization is employed on current model versioning systems, which allows the derivation of challenges in this research area.

The results of the evaluation show that several challenges need to be addressed in future developments of VCSs and merging tools in order to allow the parallel development of model artifacts.

Making model‐driven engineering (MDE) a success requires supporting the parallel development of model artifacts as is done nowadays for text‐based artifacts. Therefore, model versioning capabilities are a must for leveraging MDE in practice.

The paper gives a comprehensive overview of collaboration features of VCSs for software engineering artifacts in general, discusses the state‐of‐the‐art of systems for model artifacts, and finally, lists urgent challenges, which have to be considered in future model versioning system for realizing MDE in practice.