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Geometric structure error of parabolic trough concentrator (PTC) frame affects the installation accuracy of mirrors and absorber tubes and thus decreases the solar energy concentrating efficiency. Until now, there is no effective method to instruct the assembly and regulation of PTC frames. This paper aims to propose a vision guided method for fast and accurate regulation of mirror and absorber supports to improve the geometric quality of PTC frames.

The PTC frame support regulating system consists of a general-purpose online photogrammetry system, frame support measurement adaptors and data analyzing software. First, the positions and angles of all the supports are measured in real time by the online photogrammetric system. Then, the measured positions and angles are aligned to the design reference frame through the transformation calculated by an absorber position constrained nonlinear optimization so as to get the geometric errors and regulating amounts. Finally, a graduated pseudo-color-based visualization method is proposed to assist the manual or automated regulation of PTC frame supports in site.

The proposed method does not need to construct a reference system nor specify the rotation attitude of the PTC frame, and it is capable of conducting efficient and accurate regulation on PTC frame assembly line. The method is applied to manual regulation of a light type PTC frame structure. After regulation, the maximum position and angle errors of supports are reduced to less than 0.15 mm and 0.15° respectively and the intercept factor is increased to 97%, which meets the requirement for a qualified PTC concentrator.

To the authors’ knowledge, this paper is the first to propose a vision guided assembly or regulation method for PTC frame structures. The research uses online photogrammetry system to provide real-time geometric quality information feedback, elaborates the data analysis algorithm and provides the visualization method for accurate and efficient in site regulation. Furthermore, this paper also provides theories, methods and experiences for other applications that use vision guidance for attitude regulation and digital flexible assembly of large equipment.

Light, when constructed in terms of the elementary quanta of light, may be viewed in particle‐like or wave‐like terms. The elementary quanta of light, when placed in motion through space/time at a speed of a constancy of c forms a light path through the space or reference frame viewed. The light path formed is curved, as space/time is curved. The curvilinear light path formed is a function of the gravitational potential within the viewed frame of reference. The linear description of this light path, termed the geodesic (Riemannian), does not describe the curvilinear light path, but rather the chord of the curvilinear path described by the inscribed arc. This linear description of the light path is the manner in which we describe the coordinate system involved, and is the same manner in which we determine the “speed of light”. The arc length of the light path, compared to the lesser value as described by the chord length, allows for a displacement to be determined, if both measures are applied to a linear measure. A displacement of linear coordinates then occurs, with this displacement a result of the gravitational potential occurring within the frame viewed. This displacement, derived via observation and predictions of the quantum model, resolves Maxwell as well as Newton. The theory concludes that the Special Theory of Relativity, suitably modified to account for gravitational displacement within one particular frame, derives a precise relative model of gravitation within the special frame. This model satisfies Newton, as the model arrives at an exact description of the three‐body problem.

The purpose of this paper is to nuance the perception about professional documentation (a.k.a. “grey literature”), assuming perception of documentation being a cultural aspect of accessibility.

The study explores variations within the archaeological report genre through a bibliometric analysis of source use. Source characteristics are explored as well as correlations between report authors and source originators. Statistical frequency distribution is complemented by a correspondence analysis and a k-means cluster analysis to explore patterns. The patterns are interpreted as “frames of references” and related to circumstances for archaeological work. The study also discusses source representations.

The source use patterns reveal a latent variation, not visible in the general analysis: a professional/academic frame of reference (mainly among authors affiliated with incorporated businesses and sole proprietorships) and an administrative frame of reference (mainly among authors affiliated with government agencies, foundations, and member associations) emerge.

The study focuses on Swedish field evaluation reports. Future research could test the results in relation to other types of reports and go beyond the document perspective to explore source use in documentation practices.

The results on variations in frames of references among report writers have implication for report readers and user. The results should also be considered in archaeology management and policy-making. On the level of source representation the results call for clarifications of vague representations and possibly omitted sources.

This study contextualizes archaeological information use and focuses on variations in professional archaeology which has received little previous research attention. The bibliometric approach complements previous qualitative studies of archaeological information.

The study of anticipatory systems assumes the existence of two distinct types of systems in nature. Some systems anticipate the future and such anticipation forms part of the system itself, while other systems, however, do not anticipate and solely rely on past states. This article aims to argue that this distinction is inadequate given the current understanding of fundamental physics and it seeks to propose instead that all systems need to be considered fundamentally anticipatory.

The analysis centers on showing how classical and quantum mechanics implies the concept of anticipatory system by showing how systems are relational and inherently anticipatory because of the potential interaction from a given reference frame of another system.

This article shows the fundamental relationship between the physical state of the system and its energy, first in classical mechanics and then in quantum mechanics. This serves, first, to remind that energy is arbitrary and so is the system, and second, that the role of potential energy is precisely one of anticipation of interaction with another system at the boundaries.

This article shows there is a fundamental concept of anticipation built in the concept of a closed system, but open systems can get around the analysis presented.

Systems engineering and decision theory fields may benefit from a renewed understanding of the role of anticipation in systems.

This analysis contributes to the fundamental understanding of the concept of anticipation, systems, and their fundamental role in physics.

This chapter takes a socioemotional wealth (SEW) perspective to explain the adoption of human resource (HR) practices in family-controlled firms. Previous studies on human resource management (HRM) in family firms have focused only on a small range of HR practices and have rarely utilized strong conceptual frameworks. As a result, these studies have overlooked important factors that contribute to the distinctiveness of HRM in these organizations. Based on ample evidence that shows family businesses' preference for non-economically motivated objectives collectively labeled as SEW, we propose that the presence of SEW influences HR practices in family firms.

Consequently, we reexamine existing empirical evidence of the determinants of HRM in family-controlled firms under the SEW approach. We also reinterpret existing theoretical models of family-controlled firms and their implications for HRM under the SEW umbrella. Our final goal is to establish an integrated framework through a set of sound propositions on HRM in family businesses. By integrating the literature, we aim to fill theoretical gaps in our understanding of the determinants of HR practices in the family business context and direct future research in this area.

This study investigates the origins and elaboration of the managerial “unitary” frame of reference associated with Alan Fox, focusing on unionised firms: the industrial relations context, intellectual roots, elaboration, adaptation by other writers, and international applicability.

Tracing the above requirements through contemporaneous sources.

Fox’s designation of the unitary frame needs to be understood in its 1960s’ context, particularly the promotion of “productivity bargaining”, and its furthering through management training and education. Fox’s specific contribution is identified. Subsequent UK writers have underplayed the importance of the legal dimension of managerial authority, especially relevant in the US context, while other extra-economic factors bolster the managerial unitary frame in authoritarian societies such as China.

The use of Fox's neglected 1960s’ writings; tracking how Fox developed the unitary frame concept and how it was funnelled into the narrow parameters of non-unionism by subsequent writers; identifying its applicability beyond the UK (with the USA as a historical example and China as a contemporary one).

Classical control theory and modern control theory satisfy the Galilean principle of relativity. If the velocity v of controlled systems is high that is to say, v approaches the velocity of light in vacuo, then the existing control theories must be transformed into relativistic form, i.e. based on relativistic physics, we must reform relativistic control theory, making it satisfy Einstein’s principle of relativity. Based on this, some properties of relativistic control theory are discussed in this paper.

This study aims to propose a national frame of reference for the accreditation of engineering programs (EPs) in Tunisia. It uses as a benchmark the structure used by the world’s leading accreditation systems such as the Accreditation Board for Engineering and Technology (ABET) and Commission des Titres d’Ingénieur. It provides a comprehensive framework for academic institutions to evaluate the performance of their programs. In addition, it suggests the procedures, steps and timeline for the application process and defines the required documents that should be submitted.

The study analyzes the standards applied by well-established accreditation agencies such as ABET, Commission Titre Ingenieur and European Accredited Engineer, studies the perceptions of academicians who participated in six workshops and uses the results of surveys and interviews to characterize their opinions about accreditation. A sample population of 146 faculty members, experts and policymakers from 23 different higher education institutions in Tunisia, who had participated in the workshops mentioned above, was solicited to participate in the survey. The opinions of 51 respondents who responded to the survey were analyzed. This methodology led to the establishment of a proposed national frame of reference for accreditation of EPs.

Analysis reveals that the Ministry of Higher Education and Scientific Research (MHESR) provides authorization (“habilitation”) to institutions allowing them to offer their educational program. However, it is inaccurate to consider this procedure as accreditation because it is more of a licensure process. In addition, the MHESR grants the “habilitation” to those institutions that successfully apply. The National Authority for Assessment, quality assurance and accreditation Instance Nationale de l’Evaluation, de l’Assurance Qualité et de l’Accréditation (IEAQA) is not involved in this process, which makes the latter’s role trivial.

This frame of reference will help the MHESR to evaluate the EPs based on a comprehensive analysis of well-established accreditation systems, to improve its “habilitation” process by splitting it into two parts as per international practice, namely, licensure and accreditation and to make the existence and role of the IEAQA much clearer.

This study is the foremost study to propose a comprehensive frame of reference for accrediting EPs in Tunisia.

To outline a philosophical system of inquiry that may be used as a frame‐of‐reference for modelling social systems.

The paper draws on insights from cognitive science, autopoiesis, management cybernetics and non‐linear dynamics.

The outcome of this paper is an outline of a frame‐of‐reference to be used as a starting point (or a frame of orientation) for any problem solving/modelling intent or act. The framework highlights the importance of epistemological reflection and the need to avoid any separation of the process of knowing from that of modelling. It also emphasises the importance of inquiry into the assumptions that underpin the methods, tools and techniques that we employ, and into the tacit beliefs of the human actors who use them.

The presented frame‐of‐reference should be regarded as an evolving system of inquiry, one that seeks to incorporate contemporary human insight.

Exactly, how the frame‐of‐reference presented in this paper should be exploited within an organisational or educational context, is a question to which there is no single “correct” answer. What is primarily important, however, is that it should be used to raise the profile of, and disseminate the benefits that accrue from, inquiry which goes beyond the simple application of tools and methods.

This paper proposes a new framework‐of‐reference for modelling social systems that draws on insights from cognitive science, autopoiesis, management cybernetics and non‐linear dynamics.

We investigate how different cognitive conceptualizations of reference point and tax withholdings jointly influence aggressive tax filing. We utilize a field study with responses captured from actual taxpayers immediately after filing their returns. Consistent with both prospect theory and mental accounting perspectives, we hypothesize and find evidence that more aggressive filing decisions depend on mental categorization of whether taxpayers expect a tax refund or owe additional taxes relative to their expected asset position (EAP). We find a joint and additive impact of EAP with a cognitive link made between taxes and the categorization of amounts owed. Our findings suggest that more aggressive filing behavior is found in taxpayers in a tax loss position relative to their EAP and in those that do not separately categorize taxes owing from their own resources. By highlighting the importance of EAP and the cognitive separation of taxes owed, we provide insight for revenue agencies to use cognitive framing strategies to mitigate aggressive taxpayer behavior. The cognitive framing of EAP may be influenced by the use of installment payments and tax withholdings, but also may be affected by communications that alter taxpayers' expectations of taxes owed.