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THE equations governing the motion of a viscous fluid were first obtained by Navier more than 100 years ago (“Memoire sur les Lois du Mouvement des Fluides,” Mem. de l'Acad. des Sciences, vi, 389, 1822), and, in spite of their close study by Stokes, Helmholtz, Kelvin, Rayleigh, Lamb, and numerous other mathematicians of great eminence, no complete unrestricted solution for any case of practical importance has yet been discovered. As they stand, the mathematical difficulties presented by the equations have so far been found to be too formidable, and whatever progress has been achieved has been by imposing restrictions on the form of the equations, and therefore serious limitations on the nature of the fluid motion studied. It may be that the mathematical symbolism in the formulation of the problem of viscous fluid flow as usually presented is not that best adapted for its purpose, that it is not as natural a medium of expression as, for example, tensor analysis is for relativity; that, in fact, the essential factors that govern the eddying, for instance, in the wake of a moving body are not presented as governing the structure of the equations.

In this paper we examine some fundamental epistemological issues in building theory for applied management science, by which we mean theory that can be usefully applied in a scientific approach to management research and practice. We first define and distinguish “grand theory” from “mid-range theory” in the social and management sciences. We then elaborate and contrast epistemologies for (i) building “grand theory” intended to be applicable to all cases and contexts, and (ii) building “mid-range theory” intended to apply to specific kinds of contexts. We illustrate the epistemological challenges in building grand theory in management science by considering important differences in the abilities of two “grand theories” in strategic management – industry structure theory and firm resources theory – to support development of conceptually consistent models and propositions for empirical testing, theoretical refinement, and application in management practice. We then suggest how a mid-range theory building approach can help to achieve integration of the two grand strategic management theories and improve their ability to support empirical testing, theory refinement, and application of theory in practice. Finally, we suggest how the competence-based management (CBM) perspective provides the foundational concepts needed to build both mid-range theory and (potentially) grand theory in strategic management that can be usefully applied in management science.

The purpose of this paper is to study the modelling mechanisms of several grey incidence analysis models with great influence, including Deng’s grey incidence model, absolute degree of grey incidence model, slope degree of incidence model, similitude degree of incidence model and closeness degree of incidence model; then analyse the problems to be solved in grey incidence analysis models; and clarify the applicable ranges of commonly used grey incidence models.

The paper comes to conclusions by means of comparable analysis. The authors compare several commonly used grey incidence analysis models, including Deng’s grey incidence model, absolute degree of grey incidence model, slope degree of incidence model, similitude degree of incidence model and closeness degree of incidence model and give several examples to clarify the reasons why quantitative analysis results of different models are not exactly the same.

As the intension of each kind of incidence model is clear and the extension is relatively obscure, grey incidence orders calculated by different incidence models are often different. When making actual decisions, incompatible results may appear. According to different characteristics of extraction, grey incidence analysis models can be divided into three types: incidence model based on closeness perspective, incidence model based on similarity perspective and incidence model based on comprehensive perspective.

The conclusions obtained in this paper can help people avoid some defects in the process of actual selection and choose the better incidence analysis model.

The conclusions can be used as a reference and basis for the selection of grey incidence analysis models, it can help to overcome the defects and shortcomings of models caused by themselves and screen out more excellent analytical models.

The purpose of this paper is to investigate the applicability of lean and green practices to foundry industry in India for improving productivity and eliminating waste, incorporating the sustainability into business performance measures.

The study used survey questionnaire method to collect data against 16 lean and green practices from 71 middle- to senior-level professionals belonging to Indian foundry industry. The survey instrument of lean and green practices was developed based on a number of sources from the literature and formal discussions with academicians and foundry industry professionals. The responses were received on a five-point Likert scale ranging from least applicable to most applicable. Exploratory factor and reliability analyses are conducted to obtain and validate constructs and measure each constructs Cronbach’s α (i.e. a consistency coefficient). The lean and green practices are categorized into the four constructs, namely, workplace organization practices, management practices, inventory control practices, and industrial manufacturing and quality improvement practices. Further, descriptive statistics is employed to find out the relative significance of lean and green practices.

Factor and reliability analyses show that all four constructs are adequate and reliable to illustrate lean and green practices. Descriptive statistics indicates that lean and green practices are applicable for implementation to a certain extent in the foundry industry. Correlation analysis shows that lean practices are positively and moderately interrelated with green practices. Thus, the results present a strong evidence that lean and green practices are moderately applicable for implementation in the foundry industry.

The paper provides insights into the applicability of lean and green practices implementation in the context of a developing country and presents evidence that lean and green practices are moderately applicable in the foundry industry. In addition, this paper is one of the few efforts to promote sustainable development within the industry.

This paper aims to establish a piecewise Maxwell stress analytical model of bearingless switched reluctance motor (BSRM) for the full rotor angular positions. The proposed model varies from the existing models, which are only applicable to the partial-overlapping positions of stator and rotor poles. By extending the applicable rotor angular positions, this model provides a basic analytical model for the multi-phase excitation control of BSRM.

The full rotor angular positions are classified into the partial-overlapping positions and the non-overlapping positions. At first, two different air gap subdividing methods are proposed, respectively, for the two-position ranges. Then, different integration paths are selected accordingly. Furthermore, two approximate methods are presented to calculate the average flux density of each air gap subdivision. Finally, considering the mutual coupling between the two perpendicular radial suspension forces, a piecewise Maxwell stress analytical model is derived for the full rotor angular positions of BSRM.

A piecewise Maxwell stress analytical model of BSRM is built for the full rotor angular positions, and applicable to the multi-phase excitation mode of BSRM. For the partial-overlapping positions and the non-overlapping positions, two sets of air gap subdividing methods, integration paths and approximate calculation methods of air gap flux densities are proposed, respectively. The accuracy and reliability of the proposed model are verified by the finite element method.

The piecewise Maxwell stress analytical model of BSRM for the full rotor angular positions is proposed for the first time. The novel air gap subdividing methods, integration paths, approximate calculation methods of air gap flux densities and the coupling between the two radial suspension forces are adopted to improve the modeling accuracy. As the applicable range of rotor angular position is extended, this model overcomes the limitation of the existing models only for single-phase excitation mode and contributes to the accurate control of BSRM multi-phase excitation mode.

This article is concerned with four major propositions: 1) The next major thrust in long‐range planning will come in the public sector, and is a thrust long overdue. 2) Over the past two decades we have significantly improved corporate planning in the private sector. We still have much to learn, but compared with the early efforts we are now high on the learning curve. 3) The fundamental lessons we have learned in the private sector in doing comprehensive long‐range planning are applicable to the introduction, development, and success of aggregate integrated long‐range planning in the public sector. 4) It is imperative that a dialogue begin immediately between practitioners of long‐range planning in the private sector and those in the public sector who are directly involved in the development of this process. Both groups have much to learn from each other, but it is particularly important that those in the public sector be exposed to the first‐hand experience of those in the private sector.

This paper aims to discuss the relationship between the continued fraction form of the analytical solution in the frequency domain, the orthogonal function expansion and their circuit realization to derive an efficient representation of the eddy-current field in the conducting sheet and wire/cylinder. Effective frequency ranges of representations are analytically derived.

The Cauer circuit representation is derived from the continued fraction form of analytical solution and from the orthogonal polynomial expansion. Simple circuit calculations give the upper frequency bounds where the truncated circuit and orthogonal expansion are applicable.

The Cauer circuit representation and the orthogonal polynomial expansions for the magnetic sheet in the E-mode and for the wire in the axial H-mode are derived. The upper frequency bound for the Cauer circuit is roughly proportional to N⁴ with N inductive elements, whereas the frequency bound for the finite element eddy-current analysis with uniform N elements is roughly proportional to N².

The Cauer circuit representation is expected to provide an efficient homogenization method because it requires only several elements to describe the eddy-current field over a wide frequency range.

The applicable frequency ranges are analytically derived depending on the conductor geometry and on the truncation types.

The Consultation and Relational Empathy (CARE) Measure is a validated tool for assessing the patients' perception of the doctors' communication in primary care. The present study aims to evaluate the potential usefulness of the CARE Measure in secondary care in a single Hospital Trust in Scotland.

A total of 1,015 out‐patients attending 25 consultants across ten specialities anonymously completed the questionnaire immediately after their appointment. Overall satisfaction, estimated consultation length, satisfaction with consultation length, and demographic and socio‐economic variables were also recorded.

The number of missing values and “not applicable” responses to the ten CARE Measure items was extremely low (3.4 per cent). Almost 90 per cent of patients felt the CARE Measure items were of major importance. The measure had a high internal reliability (Cronbach's alpha 0.94) and reduced to a single factor. Overall CARE Measure score correlated with overall satisfaction (r=0.7, p<0.0001), whether patients would recommend the doctor (r=0.6, p<0.0001), and satisfaction with consultation length (r=0.6, p<0.0001). Multi‐regression analysis showed that personal continuity of care, consultation length, and patient age positively influenced CARE Measure score, but the effect size was small. Patients' gender, marital status, general health, and socio‐economic factors did not influence scores. Reliability analysis indicated that 40 patients were required per doctor in order to achieve an overall reliability co‐efficient of above 0.7.

Secondary care patients across a range of specialities have endorsed the CARE Measure as a relevant tool. It has high face and concurrent validity, internal and structural reliability and is not subject to major influences by demographic or socio‐economic factors. These findings support the feasibility and reliability of the CARE Measure in secondary care.

This pilot study indicates that the CARE Measure is considered by most patients to be of high relevance to everyday out‐patient consultations in secondary care.

The purpose of this paper is to show that it is advisable to evaluate draught in an operating theatre in a different manner than the method according to NEN‐EN‐ISO‐7730. The NEN‐EN‐ISO‐7730 is an international standard for the analytical determination and interpretation of the thermal comfort of the human body and the local thermal comfort like for instance draught.

Using a CFD computer program, it is possible to evaluate draught in an operating theatre in the design stage, according to different mathematical draught models.

It would seem advisable to begin with the draught model developed by Griefahn. The model does, however, need to be modified to include the effects of temperature sensation and the direction of the air stream, so that it becomes applicable to a thermally cool environment (PMV<0) and a vertical air stream, the air pattern prescribed for an operating theatre.

It can be demonstrated that by implementing the proposal in this paper in a CFD program, the possibility exists to be able to evaluate, in a responsible fashion, the results for a much broader range of parameters than is currently possible by means of the NEN‐EN‐ISO‐7730.

The purpose of this research is to provide the necessarily and resourceful information regarding range sensors to select the best fit sensor for robust autonomous navigation. Autonomous navigation is an emerging segment in the field of mobile robot in which the mobile robot navigates in the environment with high level of autonomy by lacking human interactions. Sensor-based perception is a prevailing aspect in the autonomous navigation of mobile robot along with localization and path planning. Various range sensors are used to get the efficient perception of the environment, but selecting the best-fit sensor to solve the navigation problem is still a vital assignment.

Autonomous navigation relies on the sensory information of various sensors, and each sensor relies on various operational parameters/characteristic for the reliable functioning. A simple strategy shown in this proposed study to select the best-fit sensor based on various parameters such as environment, 2 D/3D navigation, accuracy, speed, environmental conditions, etc. for the reliable autonomous navigation of a mobile robot.

This paper provides a comparative analysis for the diverse range sensors used in mobile robotics with respect to various aspects such as accuracy, computational load, 2D/3D navigation, environmental conditions, etc. to opt the best-fit sensors for achieving robust navigation of autonomous mobile robot.

This paper provides a straightforward platform for the researchers to select the best range sensor for the diverse robotics application.