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The purpose of this paper is to propose a novel measurement technique and a modelless calibration method for improving the positioning accuracy of a three-axis parallel kinematic machine (PKM). The aim is to present a low-cost calibration alternative, for small and medium-sized enterprises, as well as educational and research teams, with no expensive measuring devices at their disposal.

Using a chessboard pattern on a ground-truth plane, a digital indicator, a two-dimensional eye-in-hand camera and a laser pointer, positioning errors are explored in the machine workspace. With the help of these measurements, interpolation functions are set up per direction, resulting in an interpolation vector function to compensate the volumetric errors in the workspace.

Based on the proof-of-concept system for the linear-delta PKM, it is shown that using the proposed measurement technique and modelless calibration method, positioning accuracy is significantly improved using simple setups.

In the proposed method, a combination of low-cost devices is applied to improve the three-dimensional positioning accuracy of a PKM. By using the presented tools, the parametric kinematic model is not required; furthermore, the calibration setup is simple, there is no need for hand–eye calibration and special fixturing in the machine workspace.

Measurement-while-drilling (MWD) system has been used to provide trajectory and inclination parameters of the oil and gas well. Fluxgate magnetometer is a traditional choice for one MWD system; however, it cannot obtain effective trajectory parameters in nonmagnetic environments. Fiber-optic-gyroscope (FOG) inclinometer system is a favorable substitute of fluxgate magnetometer, which can avoid the flaws associated with magnetic monitoring devices. However, there are some limitations and increasing surveying errors in this system under high impact conditions. This paper aims to overcome these imperfections of the FOG inclinometer system.

To overcome the imperfections, filtering algorithms are used to improve the precision of the equipment. The authors compare the low-pass filtering algorithm with the wavelet de-noising algorithm applied to real experimental data. Quantitative comparison of the error between the true and processed signal revealed that the wavelet de-noising method outperformed the low-pass filtering method. To achieve optimal positioning effects, the wavelet de-noising algorithm is finally used to inhibit the interference caused by the impact.

The experimental results show that the method proposed can ensure the azimuth accuracy lower than ±2 degrees and the inclination accuracy lower than ± 0.15 degrees under the condition of interval impact. The method proposed can overcome the interference generated by the impact in the well, which makes the instrument suitable for the measurement of small-diameter casing well.

After conducting the wavelet threshold filtering on the raw data of accelerometers, the noise generated by the impact is successfully suppressed, which is expected to meet the special requirement of the down-hole survey environment.

This study analyzes the static and dynamic risk spillover between US/Chinese stock markets, cryptocurrencies and gold using daily data from August 24, 2018, to January 29, 2021. This study provides practical policy implications for investors and portfolio managers.

The authors use the Diebold and Yilmaz (2012) spillover indices based on the forecast error variance decomposition from vector autoregression framework. This approach allows the authors to examine both return and volatility spillover before and after the COVID-19 pandemic crisis. First, the authors used a static analysis to calculate the return and volatility spillover indices. Second, the authors make a dynamic analysis based on the 30-day moving window spillover index estimation.

Generally, results show evidence of significant spillovers between markets, particularly during the COVID-19 pandemic. In addition, cryptocurrencies and gold markets are net receivers of risk. This study provides also practical policy implications for investors and portfolio managers. The reached findings suggest that the mix of Bitcoin (or Ethereum), gold and equities could offer diversification opportunities for US and Chinese investors. Gold, Bitcoin and Ethereum can be considered as safe havens or as hedging instruments during the COVID-19 crisis. In contrast, Stablecoins (Tether and TrueUSD) do not offer hedging opportunities for US and Chinese investors.

The paper's empirical contribution lies in examining both return and volatility spillover between the US and Chinese stock market indices, gold and cryptocurrencies before and after the COVID-19 pandemic crisis. This contribution goes a long way in helping investors to identify optimal diversification and hedging strategies during a crisis.

Argues that the unidirectional measurement and evaluation of service quality in any specific service encounter is not enough in itself to understand the existing service quality between two actors in a dyadic service encounter. Therefore, a method is introduced for the express purpose of analysing the perceptual bi‐directionality of service quality in order to measure and evaluate the dynamics of service quality in dyadic service encounters.

The purpose of this paper is to develop a method for defining and categorizing upper lateral somatotypes for clothing size systems used for clothing pattern creation based on directional angles of 3D space vectors.

3D data for 317 men in their twenties obtained from the fifth Size Korea survey were used in this study. Standard landmarks and surfaces were set on the 3D shapes, and six space vector angles of the lateral form were defined and measured. Relationships among the measurement results were clarified, and the results were compared with those obtained using existing classifying methods.

The measurement of the defined directional angles indicated that the swayback type and bend-forward type had the two extreme values, and the straight type was between the two values. The analysis of the correlation between six directional angles indicated that some points in the lower area of the upper body had a high correlation with other points in the lower area.

The subjects of this study were limited to lateral somatotypes, and there is a need for future studies that focus on frontal somatotypes. This research is confined to the upper lateral somatotypes of men in their twenties. Further study is needed to extend the results of this study to other body types such as those of elderly and overweight persons.

Major angle measurements quantified by the somatotypes can be specifically reflect in developing and revised to the right patterns which is spread body shell replica or individual pattern for MTM.

This objective somatotype analysis method can be involved in determining individual body somatotype of ordermade clothes or can provided the accurate information interactively to MTM automatic customized pattern making system.

Accurate measurements of size, shape, and posture were applied and characterized to realize the process. Accuracy was improved compared to existing 2D analysis methods through three-dimensional analysis using directional space vector angles based on 3D forms.

The purpose of this paper is to propose a new inspecting algorithm for defect detection on PCB circuits.

PCB circuit images were processed by a radon transformation. A Radon histogram was formed and utilized to establish a texture directional characteristic similarity function. Then, a region of the image which contained the same texture directionality feature was segmented. Furthermore, a directionality estimation method is presented. As the circuit was damaged, the directionality was weakened correspondingly. According to principle, the concept of directional intensity was proposed and then used to measure directionality through analysis of the Radon histogram fluctuation. Finally, the defect was detected based on directional intensity.

The method has been applied to an inspecting system used in practice and it achieved a higher accuracy and efficiency in comparison with similar methods.

Although work on highly intensive PCB circuitry inspection and flaw detection is presented, defect classification was not involved although this is also a very important requirement of inspection.

The paper provides a new way to detect PCB circuitry defects based on texture directionality and proposes evaluating the similarity between image texture directionalities using a radon transformation to search the inspected area. As the inspected region was located, the concept of directional intensity was defined to measure texture directionality to identify defects. The new algorithm performs stably and efficiently and is fit for practical application.

The unidirectional measurement and evaluation of the service quality in a specific service encounter is not enough to understand the existing service quality between two actors in a dyadic service encounter. Furthermore, a bi‐directional approach may not always be sufficient to understand the service quality in a specific service encounter. The incorporation of a third actor may improve the understanding of service quality in dyadic service encounters. Therefore, a method is applied to analyze the dynamics of service quality in triadic business networks.

The purpose of this paper is to understand how the development of social capital can promote buyer’s bi-directional (inflow and outflow) information sharing. The authors examined buyers’ perceptional differences in information sharing: when they receive information from suppliers and when they provide information to suppliers, and how such inequivalent perception in information sharing can be resolved by the level of social capital and its’ sub-dimensions.

Theoretical model and the hypotheses were developed through literature review. Data were collected from Korean manufacturers in supply chains and structural equation modelling was used for analysis.

The results show that each dimension of social capital has a different effect on bi-directional information sharing. For the information inflow, all of the facets of social capital were significant; for the information outflow, however, only relational capital was significant. That is, with cognitive and structural capital, buyers perceive that they can receive appropriate information from suppliers yet be reluctant to provide information to suppliers.

Given that relational capital is essential for the balanced information sharing in buyer-supplier relationship, firms should pay attention to having social interactions with partners to promote trust in the relationship for efficacy in information sharing.

This is one of the first studies to explore the role of social capital in facilitating equivalent information sharing. This study develops a framework that social capital can provide valuable guidance in achieving equivalency of bi-directional information sharing.

In precision robotic assembly visual sensing techniques have been widely used since they can detect large misalignments and also part's shape at a distance. Develops two novel visual sensing methodologies.

Both systems consist of four components: an inside mirror and an outside mirror, a pair of plane mirrors and a camera with a collecting lens. The difference between the two is that system A adopts a pyramidal mirror configuration, while system B employs a conic one. Owing to this configuration difference, system A can detect three‐dimensional measurements of objects with only one image capture, while in addition to this functionality system B is shown to be capable of detecting two omni‐directional image. The measurement principles are described in detail and compared with each other.

The image acquiring process is shown to easily detect the in situ status of each assembly action, while the recognition method is found to be effective to identify instantaneous misalignment between the peg and the hole. The results obtained from a series of experiments show that the proposed visual sensing methods are an effective means of detecting misalignment between mating parts even in the presence of self‐occlusion.

The proposed sensing methods will dramatically increase the rate of success when actually utilized in assembly processes.

Describes the development of two novel visual sensing methodologies.