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Quasi‐associative operators are defined and suggested as a general structure useful for representing a class of operators used to combine various pieces of evidence. We show that both averaging operators and Dempster‐Shafer combining operators can be represented in this new framework.

A three-dimensional (3D) printing error simulation approach is proposed to analyze the influence of tilted vertical beams on the 3D printing accuracy. The purpose of this study is to analyze the influence of such errors on printing accuracy and printing quality for delta-robot 3D printer.

First, the kinematic model of a delta-robot 3D printer with an ideal geometric structure is proposed by using vector analysis. Then, the normal kinematic model of a nonideal delta-robot 3D robot with tilted vertical beams is derived based on the above ideal kinematic model. Finally, a 3D printing error simulation approach is proposed to analyze the influence of tilted vertical beams on the 3D printing accuracy.

The results show that tilted vertical beams can indeed cause 3D printing errors and further influence the 3D printing quality of the final products and that the 3D printing errors of tilted vertical beams are related to the rotation angles of the tilted vertical beams. The larger the rotation angles of the tilted vertical beams are, the greater the geometric deformations of the printed structures.

Three vertical beams and six horizontal beams constitute the supporting parts of the frame of a delta-robot 3D printer. In this paper, the orientations of tilted vertical beams are shown to have a significant influence on 3D printing accuracy. However, the effect of tilted vertical beams on 3D printing accuracy is difficult to capture by instruments. To reveal the 3D printing error mechanisms under the condition of tilted vertical beams, the error generation mechanism and the quantitative influence of tilted vertical beams on 3D printing accuracy are studied by simulating the parallel motion mechanism of a delta-robot 3D printer with tilted vertical beams.

Presents an investigation of some aspects of the axiomization of conditional independence of probability. Contributes to the understanding of Pearl's completeness conjecture and identifies a direction for revision which could remove some of the difficulties of Pearl's axiom set, but this alternative is not without its own difficulties. This approach largely simplifies the definition of conditional independence. Then shows the completeness conjecture to be incorrect by presenting counter examples; a new axiom based on the counter examples follows. Discusses the reason for the conjecture being incorrect. Notes that an alternative conjecture could be suggested, but this raises many new questions and increases complexity. Finally, shows that “the disjointness condition on variable sets” is in fact necessary. Concludes that while the axiomization of conditional independence has attractions, it is probably too complex to be pragmatic. Suggests an alternative way forward in inexact reasoning.

This study aims to examine the effect of transglobal leadership on quality of work life (QWL), job involvement, organizational citizenship behavior (OCB) and human resource (HR) performance of tourism sector-engaged micro, small and medium enterprises (MSMEs) in East Java; to examine the moderating role of QWL, job involvement and OCB in the effect of transglobal leadership on HR performance of tourism sector-engaged MSMEs in East Java; to examine the effect of HR performance of tourism sector-engaged MSMEs on responsible tourism marketing and sustainable tourism competitiveness in East Java; and to examine the mediating role of responsible tourism marketing in the effect of HR performance of tourism sector-engaged MSMEs on sustainable tourism competitiveness in East Java.

The population of this research was all HR executives of tourism sector-engaged MSMEs in East Java and domestic and foreign tourists in East Java. The sampling of the tourism sector-engaged MSMEs in East Java (in 16 tourism potential cities) was performed using a purposive sampling technique. Determination of the sample size was made using the minimum criterion from structural model, ranging from 100 to 200. Thus, it was determined that the number of tourism sector-engaged MSMEs studied in this research was 200 enterprises from 16 tourism potential cities in East Java. From each tourism sector MSME, four employees and three tourists were selected. In total, this research involved 800 employees and 600 tourists (both domestic and foreign).

This research found that transglobal leadership (X) , QBL (M1), job involvement (M2) and OCB (M3) had an effect on HR performance (Y). The results of this research highlighted that QWL variable (M1) moderated the effect of transglobal leadership (X) on HR performance (Y). It was found that job involvement variable (M2) moderated the effect of transglobal leadership (X) on HR performance (Y). This research also detected that OCB variable (M3) moderated the effect of transglobal leadership (X) on HR performance (Y). This research found that HR performance (Y) had an effect on responsible marketing (Z1). It was obtained in this research that HR performance (Y) also had an effect on sustainable tourism competitiveness (Z2). Finally, this research found that responsible marketing (Z1) had an effect on sustainable tourism competitiveness (Z2).

Regarding the originality of this research, the holistic compilation was integrated from the theoretical concept of the HR and marketing strategies through the implementation of the tourism marketing concept and application that are responsible for tourism sector-engaged MSMEs in East Java. Of course, tourists need to get a good understanding of the marketing strategy to participate in controlling the sustainable tourism competitiveness in East Java.

A binary choice model explaining the distribution of holidays abroad undertaken by UK residents is constructed and estimated. The foreign holiday demand function is generated from a comparison of holiday costs and benefits, and stochastic behaviour is permitted. In addition, the effects of incomplete knowledge on holiday choice are incorporated in the model. It is shown that the empirical results support the theoretical framework and that the £50 foreign currency limit imposed by the British Government between 1966 and 1969 resulted in a shift in the distribution of foreign holidays.

A local equivalent linearization methodology is proposed to simulate non‐linear shock absorbers and dual‐phase dampers in the convenient frequency domain. The methodology based on principle of energy similarity, characterizes the non‐linear dual‐phase dampers via an array of local damping constants as function of local excitation frequency and amplitude, response, and type of non‐linearity. The non‐linear behaviour of the dual‐phase dampers can thus be predicted quite accurately in the entire frequency range. The frequency response characteristics of a vehicle model employing non‐linear dual‐phase dampers, evaluated using local linearization algorithm, are compared to those of the non‐linear system, established via numerical integration, to demonstrate the effectiveness of the algorithm. An error analysis is performed to quantify the maximum error between the damping forces generated by non‐linear and locally linear simulations. The influence of damper parameters on the ride improvement potentials of dual‐phase dampers is further evaluated using the proposed methodology and discussed.

The purpose of this study is to propose an automatic leveling method for a printing platform based on a three-point coordinate feedback. The proposed method is used in fused deposition modeling additive manufacturing systems. The coordinate error of the leveled plane is constrained to within  ± 0.2 mm, which is less than the printed layer thickness.

First, the model of the forward and inverse solutions of the parallel arm is obtained based on the principles of vector algebra. Second, the automatic leveling mechanism for collecting the z-coordinate is designed. The best position of the virtual origin plane is obtained by comparing the z-coordinates of the test points. Finally, after making multiple adjustments through a closed-loop z-coordinate feedback, the parallelism of the printing plane and the virtual origin plane is limited to an effective range.

The experimental results show that after three leveling attempts, the z-coordinate of the test points can be constrained to within  ± 0.2 mm, which shows that this method can effectively achieve automatic leveling in a delta three-dimensional (3D) printer.

This study presents a novel and distinctive delta 3D printer leveling system by designing a leveling mechanism and a leveling algorithm. The method uses a closed-loop feedback mode to make the leveling process simple, convenient and efficient without requiring major changes to the printer. The error after leveling is less than the printed layer thickness, which fully guarantees the accuracy of the leveling process.

The defective coin problem involves the identification of a defective coin, if any, and ascertaining the nature of the defect (heavier/lighter) from a set of coins containing at the most one defective coin, using an equal‐arm‐pan‐balance. An algorithmic analysis of the problem is considered. The solution strategy to minimise the number of weighings required to detect the defective coin is based on a problem reduction approach involving successive decomposition of the problem into subproblems until it is trivially solved. The algorithm is capable of generating all possible optimal solutions.

This study aims to treat the development and application of sequence characterised amplified region (SCAR) markers for the detection of plant based adulterants (dried red beet pulp and powdered Ziziphus nummularia fruits) in traded ground chilli.

Adulterant‐specific DNA fragments (red beet pulp specific – “Beet 01” and Z. nummularia specific – “Ziz 01”) identified by random amplified polymorphic DNA polymerase chain reaction (RAPD‐PCR) analysis were cloned and sequenced for SCAR marker development. Red beet pulp specific SCAR primer pair, B1, and Z. nummularia specific SCAR primer pair, Z1, were designed from the corresponding RAPD marker sequences to amplify SCAR markers of 320 bp and 389 bp, respectively. The utility of the SCAR markers for adulterant detection was verified in model blends of chilli powder with the adulterants. Six commercial samples of ground chilli powder were analysed using the SCAR markers.

SCAR markers could detect the adulterants at a concentration as low as 10 g adulterant kg⁻¹ of blended sample. The Z. nummularia SCAR marker could detect the presence of Z. nummularia fruit adulteration in one of the commercial samples. All the market samples tested were free from red beet pulp adulteration.

The PCR‐based method developed in the study is simple, rapid, and sensitive and has the potential to be developed into a quantitative analytical method and for commercial PCR kits for the large‐scale screening of ground chilli to detect and prevent plant‐based adulterants. The work has public health significance too, as ground chilli is one of the major spices consumed worldwide.

The study is the first report on the development of SCAR markers for adulterant detection in ground chilli. This work has relevance, as adulteration is a major concern of the sanitary and phytosanitary issues of the World Trade Organization (WTO) agreement.

A new numerical method is presented for the simulation of flows of incompressible fluids in plane or axisymmetric flows. Under certain assumptions, the physical domain can be transformed into a rectangular domain. This method can involve free surface flow problems. In Newtonian and non‐Newtonian cases, the relevant equations are non‐linear and the solution is carried out in the transformed domain where the stream lines are parallel straight lines.