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The shape error of shaft-type mechanical components directly influences the quality, fitting precision and lifespan of the components. Among these, cylindricity error is a critical indicator for evaluating the precision of shaft-type components. Based on the new generation geometric product specifications & verification (GPS), this paper researched GPS inspection operation operators, determined extraction and fitting schemes, and constructed a mathematical model for cylindricity error evaluation. Consequently, a method for cylindricity error evaluation based on an improved whale optimization algorithm was proposed. The proposed algorithm introduced chaotic mapping and nonlinear parameters during population initialization to enhance solution quality. Subsequently, adaptive weighting coefficients were incorporated during spiral position updates to improve the algorithm's local search capability. Finally, Levy flight strategies were introduced during random search to enhance the algorithm’s global search capability. This study conducted experimental validation and analysis by performing numerous comparative experiments on different extraction point numbers, cross-section numbers, evaluation criteria, and algorithms. The experimental results indicated that the proposed method for cylindricity error evaluation demonstrated significant improvements in both accuracy and efficiency compared to genetic algorithms, least squares methods, and others.

Coordinate measuring machines are widely used in the industrial field due to their ease of automation. However, estimating the measurement uncertainty is a delicate task, especially when controlling for deviation, given the large number of factors that influence the measurement. A precise estimate of the uncertainty is crucial to avoid incorrect conformity assessments. The purpose of this study is to control geometrical-form tolerance specifications, taking into consideration their associated uncertainty. A surface fitting model based on the least squares criterion is proposed, allowing one to obtain the variance–covariance matrix by iterative calculation according to the Levenberg–Marquard optimization method. The form deviation is then evaluated following the Geometrical Product Specifications (GPS) Standard, and its associated uncertainty is estimated using the guide to the expression of uncertainty in measurement (GUM) propagation of the uncertainty law. Finally, the conformity assessment is performed based on the measured deviation and its associated uncertainty. Different results for the measurement of straightness, flatness, circularity, roundness, and cylindricity are presented and detailed. This model is thereafter validated by a Monte Carlo simulation, and interlaboratory comparisons of the obtained results were performed, which showed satisfactory outcome. This contribution is of great use to manufacturing companies and metrology laboratories, allowing them to meet the normative guidelines, which stipulates that each measurement result must be accompanied by its associated uncertainty.

The Geometrical Product Specification (GPS) and the Geometrical Dimensioning and Tolerancing (GD&T) are communication languages to code the tolerable morphology of manufactured parts and assemblies. Both languages should be unambiguous tools to communicate such information between designers, process engineers, and Coordinate Measuring Machines operators (CMM). GPS is the one developed in the ISO (International Organization for Standardization) environment. GPS language is a complex code of 143 standard with further 15 under development. Moreover, as in each complex body of standards, most of them recalls other standards in a very intricate manner. So, the need to have a flexible tool to search and navigate through the standards is great, as is the need to optimize the work of the designer and to minimize the design, production, and control costs. The basic effort in building such a tool has been the development of the database and the structure for the search engine, called “GPS Navigator”. In the following, the requirements for the coding phase have also been issued, to realize a powerful, efficient, fast, robust, and rigorous tool to navigate through the GPS standards. The final step of the “GPS-Navigator project” is the delivery of a software tool able to help and guide the designer to quickly consult the appropriate standard or set of standards.

Purpose In the initial stage of product design, product portfolio identification (PPI) aims to translate customer needs (CNs) into product specifications (PSs). This is an essential task, since understanding what customers really want is at the center of product design. However, design information is incomplete and design knowledge is minimal during this stage. Furthermore, PPI is often a confusing and frustrating task, especially when customer preferences are changing rapidly. To facilitate the task, the purpose of this paper is to capture the time-sensitive mapping relationship between CNs and PSs. Design/methodology/approach This paper proposes a design sequential pattern mining model to uncover implicit but valuable knowledge from chronological transaction records. First, CNs and PSs from these records are transformed and connected according to the transaction time. Second, procedures such as litemset generation, data transformation and pattern mining are conducted based on the AprioriAll algorithm. Third, the uncovered patterns are modified and applied by engineers. Findings Using the retrieved patterns, engineers can keep up with the dynamics of customer preferences with regard to different PSs. Research limitations/implications Computational experiments on a case study of customization of desktop computers show that the proposed method is capable of extracting useful sequential patterns from a design database. Originality/value Considering the times tamps of the transactions, a sequential pattern mining-based method is proposed to extract valuable patterns. These patterns can help engineers identify market trends and the correlation among PSs.

Conceptual design has a decisive impact on the product development time, cost and success. This paper presents a new conceptual design method for achieving rapid and effective mapping from product design specification (PDS) to concept design. This method can guide the creation of reasonable mapping among the PDS, behaviour parameters and structure parameters and to evaluate the rationality of performance parameters and structure parameters to confirm a reasonable conceptual design scheme. In this method, we establish a PDS-behaviour-structure conceptual design model to support the conceptual design of multi-disciplinary-oriented complex product system (CoPS) and develop a vector-based mapping tool in this method to support the rapid mapping, and demonstrate its feasibility and effectiveness by a case study. This method is not only supportive to realise the automation of a conceptual design process but also helpful to evaluate the conceptual design in the field of engineering design.

E-navigation provides the opportunity to apply modern digital and other electronic enhancements to improve the safety and efficiency of maritime navigation. Under the broad banner of e-navigation, the International Hydrographic Organization's S-100 product specification framework is facilitating the establishment of a standard maritime data structure to enable a free-flowing exchange of navigation information between ships, ship-to-shore and shore-to-ship. There are currently over 30 S-100 based product specifications at various stages of development. For the data standard to be properly used, navigation software products must be capable of reading as well as comprehending the data format and content. To develop robust and stable software, the S-100 data models and product specifications must be consistent, accurate and interoperable in conveying various types of information. This paper describes the results of research on S-100 based product specifications from the viewpoint of developing maritime navigation software. In particular, issues related to software development for Electronic Chart Display Information System (ECDIS) and Vessel Traffic Service (VTS) are discussed, including appropriate data model analysis, processing of features, and symbols overlapping with other product specifications. Proposed solutions for some identified issues are presented.

Conformity assessment of measuring equipment (also referred to as verification) can be provided as part of the calibration procedure by accredited calibration laboratories in accordance with ISO/IEC 17025:2017 General Requirements for the Competence of Testing and Calibration Laboratories upon request. However, in practice, this task often involves significant difficulties associated with the insufficient expertise of laboratory personnel in probability theory and theoretical metrology, as well as the lack of clear and unambiguous rules on how to assess conformity. Therefore, it is necessary to develop guidelines for accredited calibration laboratories containing both theoretical explanations and specific decision rules for measuring equipment and/or specific measurement fields. The article considers the conformity assessment of measuring equipment of any kind as a whole and its separate elements: requirements for the equipment; decision rule; risk of a false accept/reject; measurement uncertainty. The rules for performing conformity assessment for geometrical product specifications, regulated by ISO 14253 series, are analyzed. Using calibration of a caliper as an example, the author considers three conformity assessment options, which differ in the applied decision rules and methods of measurement uncertainty estimation. Inconsistencies between the statements of conformity given for different conformity assessment options are noted; the practical applicability of the three considered options is analyzed. The obtained study results, including recommendations on the choice of a conformity assessment option, can be useful in the development of decision rules by accredited calibration laboratories engaged both in the measurement of geometrical product specifications and other measurement fields, as well as can enhance the expertise of specialists involved in the conformity assessment and verification of various objects.

A strategic instrument for the sustainable conservation of the fragile marine ecosystem is the designation of Marine Protected Areas (MPAs), within which various regulations exist for the protection of highly vulnerable species and habitats. These regulations can be depicted on Electronic Navigational Charts (ENCs) based on the new International Hydrographic Organization (IHO) S-100 series of standards, which support Marine Information Overlays (MIOs) that enrich the portrayed information by including both static and dynamic information, such as vessels traffic, tides, currents, and weather conditions, as well as essential information for the regulation of MPAs. Although, the new IHO S-122 Product Specification introduced specifically for the MPAs has been developed to encapsulate geospatial information for these regulations, the present edition does not specify portrayal. This paper reviews the legal foundation for the protection of marine mammals as well as the mapping methods used in selected study cases and builds upon these to present new, intuitive portrayal symbols for depicting the type of MPAs in combination with the regulations to be enforced on ENCs. Moreover, to support the global efforts for the protection of marine biodiversity, contemporary navigation systems aboard vessels can be used to enforce environmental regulations, and operations centers ashore can also monitor vessels’ passage and activities in MPAs. In that respect, this paper also discusses the concepts of Ecosystem Protection Zones and Environmental Risk Contours that can facilitate environmental risk-based voyage planning and preventive alarm services through Electronic Chart Display and Information Systems (ECDIS).

Objectives Map the current landscape of commercially available artificial intelligence (AI) software for radiology and review the availability of their scientific evidence. Methods We created an online overview of CE-marked AI software products for clinical radiology based on vendor-supplied product specifications ( www.aiforradiology.com ). Characteristics such as modality, subspeciality, main task, regulatory information, deployment, and pricing model were retrieved. We conducted an extensive literature search on the available scientific evidence of these products. Articles were classified according to a hierarchical model of efficacy. Results The overview included 100 CE-marked AI products from 54 different vendors. For 64/100 products, there was no peer-reviewed evidence of its efficacy. We observed a large heterogeneity in deployment methods, pricing models, and regulatory classes. The evidence of the remaining 36/100 products comprised 237 papers that predominantly (65%) focused on diagnostic accuracy (efficacy level 2). From the 100 products, 18 had evidence that regarded level 3 or higher, validating the (potential) impact on diagnostic thinking, patient outcome, or costs. Half of the available evidence (116/237) were independent and not (co-)funded or (co-)authored by the vendor. Conclusions Even though the commercial supply of AI software in radiology already holds 100 CE-marked products, we conclude that the sector is still in its infancy. For 64/100 products, peer-reviewed evidence on its efficacy is lacking. Only 18/100 AI products have demonstrated (potential) clinical impact. Key Points • Artificial intelligence in radiology is still in its infancy even though already 100 CE-marked AI products are commercially available. • Only 36 out of 100 products have peer-reviewed evidence of which most studies demonstrate lower levels of efficacy. • There is a wide variety in deployment strategies, pricing models, and CE marking class of AI products for radiology.

The new EU basic regulation for spirit drinks No. 2019/787 still contains a chapter with regard to the protection of geographical indications (GI) but with some significant modifications compared to the former Regulation 110/2008. In future only private groups composed mainly of producers or processors have got the right to apply for a new GI or for modification of the product specifications. The registration procedure for a new GI or for Union amendments will be a two-step procedure with a national administration procedure at the first step. The Geneva protocol for the Lisbon agreement protects GI besides protected denominations of origin.