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Autonomous mobile robots (AMRs) play a crucial role in industrial and service fields. The paper aims to build a LiDAR-based simultaneous localization and mapping (SLAM) system used by AMRs to overcome challenges in dynamic and changing environments.

This research introduces SLAM-RAMU, a lifelong SLAM system that addresses these challenges by providing precise and consistent relocalization and autonomous map updating (RAMU). During the mapping process, local odometry is obtained using iterative error state Kalman filtering, while back-end loop detection and global pose graph optimization are used for accurate trajectory correction. In addition, a fast point cloud segmentation module is incorporated to robustly distinguish between floor, walls and roof in the environment. The segmented point clouds are then used to generate a 2.5D grid map, with particular emphasis on floor detection to filter the prior map and eliminate dynamic artifacts. In the positioning process, an initial pose alignment method is designed, which combines 2D branch-and-bound search with 3D iterative closest point registration. This method ensures high accuracy even in scenes with similar characteristics. Subsequently, scan-to-map registration is performed using the segmented point cloud on the prior map. The system also includes a map updating module that takes into account historical point cloud segmentation results. It selectively incorporates or excludes new point cloud data to ensure consistent reflection of the real environment in the map.

The performance of the SLAM-RAMU system was evaluated in real-world environments and compared against state-of-the-art (SOTA) methods. The results demonstrate that SLAM-RAMU achieves higher mapping quality and relocalization accuracy and exhibits robustness against dynamic obstacles and environmental changes.

Compared to other SOTA methods in simulation and real environments, SLAM-RAMU showed higher mapping quality, faster initial aligning speed and higher repeated localization accuracy.

The purpose of this paper is to ascertain the monthly seasonality in the Indian stock market after taking into consideration the market features of leptokurtosis, volatility clustering and the leverage effect.

Augmented Dickey-Fuller, Phillips-Perron and Kwaitkowski-Phillips-Schmidt-Shin tests are deployed to check stationarity of the series. Autocorrelation function, partial autocorrelation function and Ljung-Box statistics are employed to check the applicability of volatility models. An exponential generalized auto regressive conditionally heteroskedastic model is deployed to test the seasonality, where the conditional mean equation is a switching model with dummy variables for each month of the year.

Though the financial year in India stretches from April to March, the stock market exhibits a November effect (returns in November are the highest). Cultural factors, misattribution bias and liquidity hypothesis seem to explain the phenomenon.

The paper endeavors to provide a review of possible explanations behind month-of-the-year effect documented in literature in the past four decades. Further, the unique evidence from the Indian stock market supports the argument in the literature that monthly seasonality, by nature, may not be a consistent/robust phenomenon. Therefore, it needs to be examined from time to time.

As the seasonality in the stock market and resultant anomalies are dynamic phenomena, the paper reports the current seasonality/anomalies prevalent in the Indian market. This would aid investors in designing short-term investment portfolios (based on anomalies present) in order to earn abnormal returns.

This paper aims to analyse the conceptual bases of the related terms of “host” and “guest” in Chinese and reveal essential, though overlooked, cultural differences that relate to “hospitality” in Western and Chinese cultural contexts.

A presupposition of this conceptual investigation is that culture manifests itself linguistically. The analytic approach used here is textual analysis. Confucian classical texts are the main source of evidence for examining the conceptual commitments of the Chinese characters 主 and 客 and their corresponding practical expressions.

Cross-cultural comparison reveals asymmetries between the term “hospitality” and its Chinese translations, etymologically and culturally. This study demonstrates how the Chinese 主–客 paradigm is both hierarchal in nature and centred on the role and interests of the host. It further compares this paradigm with its Western counterpart along five different dimensions.

The specific Chinese norms for the host–guest paradigm synthesized here could prompt both academicians and operators to question the cultural attachments associated with hospitality by participants and the cultural differences in hospitality transactions and management. The cultural sensitivity modelled here is intended to facilitate harmony between a hospitality setting and the culture in which it is embedded.

This conceptual paper is the first in the Anglophone literature to explore the Chinese cultural roots of the concepts “host” and “guest”. The linguistic perspective used in this study allows the concept of “hospitality” to be studied cross-culturally and in an interdisciplinary way, addressing a blind spot in the extant hospitality literature.

This paper aims to investigate the corrosion inhibition efficiency of Landolphia heudelotii (LH) on mild steel in 1 M HCl and 0.5 M H₂SO₄ using weight loss and potentiodynamic polarization techniques.

Water extract of LH was used as corrosion inhibitor on mild steel in acidic media at room temperature and elevated temperatures (30-60°C). Various concentrations of the plant extract were prepared from the stock solution obtained after solvent extraction. The inhibition efficiency of LH extract was evaluated and mechanism of adsorption was deduced.

LH extract showed significant corrosion inhibition on mild steel in both acidic media, with inhibition efficiency increasing with extract concentration. Potentiodynamic polarization measurements revealed mixed inhibition mechanism. Optimum inhibition efficiency was recorded at 2500 mg/L after 288 h. Mechanism of adsorption was mainly of physisorption. The inhibitor exhibited good inhibition efficiency even at elevated temperature.

This study provides new data on the anticorrosion characteristics of LH extract under the specified conditions. Further studies could expand the experimental variables and use advanced surface probe techniques.

The developed inhibitor provides an alternative method of inhibiting corrosion on mild steel using eco-friendly materials from natural products which are less toxic, safer, cost-effective and readily available.

The method used was effective and the inhibitor developed can be incorporated in surface coatings where mild steel is used as construction materials, as tube sheets, rods and bars.

As humanitarian logistics (HL) functions in complicated, changing and ambiguous situations, all people, particularly the educated youth, have to know how to control the situation and assist victims, which are best achieved through formal education and training. Teaching at university has been extensively used in the context of business logistics. However, education in HL is a poorly researched field and, consequently, this article explores education for sustainable development in HL. The study addresses the following research question: How the teaching of HL at university can help to increase HL performance (HLP) and to reduce suffering.

A covariance-based structure equation modeling (CB-SEM) is implemented on the basis of confirmatory factor analysis.

The results show that the association between the explanatory variables and the dependent variable (HLP) is mediated by sustainability, and that the teaching of HL at university plays a vital role in enhancing HLP and is therefore a very suitable approach for sustainable development in HL. This direct approach is creative, informative and productive practice for both students and teachers.

In spite of the growing number of activities and courses in supply chain and logistics education, no study, to the best of our knowledge, has empirically analyzed the critical topic of whether or not education can bring sustainable development in HL. In order to save lives and reduce the suffering of victims, this study attempts to fill this gap.

The purpose of this paper is to evaluate the potential of natural colourants from fruits of Ixora siamensis for coating applications, to study its glossiness and effectiveness against UV‐B irradiation.

In this study, natural colourants from the fruits of Ixora siamensis were extracted using trifluoroacetic acid‐methanol solution. Anthocyanins and organic acid variants were mixed together to form co‐pigments. Different concentrations of ferulic and gallic acid co‐pigments were added to a blended solution of poly (vinyl alcohol), PVA and anthocyanin (from Ixora siamensis) to form a coating system. The coatings were exposed to UV‐B irradiation at room temperature in air using a UV‐lamp which emitted radiation at 312 nm. The effects of UV‐B irradiation on the coating system were evaluated using glossiness test and UV‐visible spectroscopy.

Anthocyanins are unstable and can quickly lose their colour. One of the methods of preserving the stability of these pigments is by co‐pigmentation. Co‐pigmentation of anthocyanin with organic acid variants resulted in an increase in both hyperchromic effects (ΔA) and bathochromic shifts (Δλ). In this study, ferulic acids yielded better results compared to gallic acids.

Samples with co‐pigmentation give better result compared to the untreated samples. The addition of 0.5 and 1.0 per cent ferulic acid improves the gloss properties and resistivity of the samples towards the UV irradiation. Thus, in order to study the effectiveness of ferulic acid as additive and improving the properties of the samples, the percentage of ferulic acid added and exposure time could be increased.

The method developed provided a simple and efficient solution for improving the UV resistance of anthocyanin blend with poly (vinyl alcohol), PVA UV absorber. Effect of ferulic acid as UV absorber, if added in more concentration, can be further studied for optimization.

The social implication is the use of local plant species as a low cost source of natural pigments in coating system.

The method for improving the resistance towards UV irradiation of anthocyanin blend with poly (vinyl alcohol), PVA was novel and could find numerous applications for natural product based on plant pigment.

Erving Goffman has been variously interpreted as a symbolic interactionist, a structural functionalist, or an a-structural power-game theorist. However, when considering Goffman’s affiliation with the human ecology (HEC) of Robert Park and Everett Hughes, one is able to shed new light on Goffman’s relationship to the aforementioned sociological paradigms. This chapter will demonstrate that his Darwinist underpinnings and overall implicit evolutionary perspective allowed him to develop a dramaturgical theory that explicates how actors are able to understand, predict, anticipate, accommodate to, and influence others while pursuing one’s own or own group’s interests, through one or more of role “taking,” “playing,” and “making.” Furthermore, Goffman elaborates upon Park’s use of dramaturgy, following him in making more room for competition and inequalities in status and power, and offering new dimensions and categories for specifying when and why different adaptive strategies will be used, within different types and degrees of accommodation. Ecological dramaturgy is the term we give to these interdependent lines of social action within stratification contexts. Such structural concerns ultimately separate Goffman from the more subjective and less deductive elements of traditional symbolic interactionist thought. We argue that Goffman’s much neglected ecological and evolutionary-minded approach to role-taking and its inspired analysis of competitive interactive processes provide a missing link in better understanding his complicated intellectual heritage.

The purpose of this paper is to contribute to the tourism management literature by: first, developing a hybrid neural network that will be able to predict tourists' overall satisfaction of their travel experience; and second, prioritizing the travel attributes based on their proportional impact on tourists' overall satisfaction of their travel experience in Iran.

A total of 1,870 questionnaires were distributed amongst foreign tourists in the departure lounge of “Imam Khomeini International Airport” over a period of three months. The data were used to develop a hybrid neural network in which the “rough set” is used to reduce travel attributes and the neural network to predict tourists' overall satisfaction of travel experience. After the model proved its predictive accuracy, using the sensitivity analysis of the neural network travel attributes were prioritized based on their impact on tourists' overall satisfaction.

The results were quite promising in that the proposed hybrid neural network was able to predict tourists' overall satisfaction with a relatively low amount of error (RMSE=0.05246). Furthermore, it was demonstrated that rough sets theory is capable to be applied effectively to feature selection of large datasets in the tourism context. Finally, it was found that “improving tourism infrastructures of the country” in addition to “globally promoting the image of Iran” (as a secure and pleasant destination) are of the highest priority for Iran's tourism industry to reach to its full potential.

Besides developing a data mining tool which is an efficient means for predicting tourists' overall satisfaction, the paper's findings provide precious information for tourism policy makers in Iran by prioritizing those travel attributes that have the greatest impact on foreign tourists' overall satisfaction of their travel experience.

Technology increasingly features in intimate relationships and is used by domestic violence perpetrators to enact harm. In this chapter, we propose a theoretical and practical framework for technology-facilitated harms in heterosexual relationships which we characterize as digital coercive control. Here, we include behaviors which can be classified as abuse and stalking and also individualized tactics which are less easy to categorize, but evoke fear and restrict the freedoms of a particular woman. Drawing on their knowledge of a victim/survivor's experiences and, in the context of patterns and dynamics of abuse, digital coercive control strategies are personalized by perpetrators and extend and exacerbate “real-world” violence.

Digital coercive control is unique because of its spacelessness and the ease, speed, and identity-shielding which technology affords. Victim/survivors describe how perpetrator use of technology creates a sense of omnipresence and omnipotence which can deter women from exiting violent relationships and weakens the (already tenuous) notion that abuse can be “escaped.” We contend that the ways that digital coercive control shifts temporal and geographic boundaries warrant attention. However, spatiality more broadly cannot be overlooked. The place and shape in which victim/survivors and perpetrators reside will shape both experiences of and response to violence. In this chapter, we explore these ideas, reporting on findings from a study on digital coercive control in regional, rural, and remote Australia. We adopt a feminist research methodology in regard to our ethos, research processes, analysis, and the outputs and outcomes of our project. Women's voices are foreground in this approach and the emphasis is on how research can be used to inform, guide, and develop responses to domestic violence.

The purpose of this paper is to examine the construction of virtual community identities among Chinese internet users and their motivation for lurking, posting or flaming.

Taking Qiangguo Luntan as an online study site the authors apply an ethnographic approach for the research, a method that is becoming more and more favourable by scholars in study virtual communities. The data gathered are mainly through participant observation and in‐depth interviews.

The findings suggest that internet bulletin boards enable ordinary Chinese to have their identities as politically activated citizens constructed in cyberspace. A consistent enthusiasm for political participation can be found in user's pennames, signature files, political clusters, and online behaviours.

This is an original case study.