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To design and fabricate a wear testing rig for a water pump impeller and to select a parameter that can be used to determine the wear rates of slurry pump impeller.

A wear equipment was designed and fabricated in this study that of main rotating shaft, supported by two ball bearings, and main electric motor bully mechanism for the rotational speed torque needed. An impeller made of cast iron was selected. The wear medium selected consists of solid particles and water. The tests were conducted by letting the impeller to rotate in slurry. The wear data collection are divided into impeller's weight loss, impeller's diameter loss, impeller blade's thickness loss, impeller's blade height loss and impeller's thickness change.

The major type of wear that takes place in this experiment is erosion. The weight loss of the impeller is due to the material removal from the impeller as result of erosion wear. The diameter loss of the impeller is attributed to the impingement of solid particles on the surface area. The surface topography under the microscope indicates that the region near the center of impeller encounters less wear compared to the region at the rim of the impeller.

From this study, among all the parameters studied, the height loss of impeller blades encounters the highest percentage of wear. This is useful for determining the running hours before the complete failure of the impeller for slurry and impeller types used in this study.

The purpose of this research is to design a robust high-performance nonlinear multi-input multi-output heating, ventilation and air conditioning (HVAC) system controller for temperature and relative humidity regulation. Buildings are complex systems which are subjected to many unknown disturbances. Further complicating the control problem is the fact that, in practice, buildings and their systems have static nonlinearities such as power saturation that make stability difficult to guarantee. Therefore, in order to overcome these issues, a control system must be designed to be robust (performance insensitive) against uncertainties, static nonlinearities and effectively respond to unknown heat load and moisture disturbances.

A state of the art nonlinear inverse dynamics (NID) technique is combined with a genetic algorithm (GA) optimisation scheme in order to improve robustness against uncertainty in the system's modelling assumptions. The parameter uncertainty problem is addressed by optimising the control system parameters over a specified range of uncertainty. The NID control structure provides further robustness with effective disturbance handling and a stability criteria that holds in the presence of actuator saturation.

The proposed method delivers significantly more energy efficient performance whilst achieving improved thermal comfort when compared with a current industry standard HVAC controller design such as proportional-integral-derivative. The expected excellent response to disturbances is also demonstrated.

This method can easily be extended to account for other parameters with a specified uncertainty range.

This research presents a method of optimised NID controller design which can be easily implemented in real HVAC controllers of building energy management systems with a high degree of confidence to provide high levels of thermal comfort whilst significantly reducing energy usage.

A novel HVAC optimised NID control strategy using the robust inverse dynamics estimation feedback control topology with GA optimisation for improved robustness and tuning over a range of parameter uncertainty is described, designed and its performance benefits shown through simulation studies.

Image classification is becoming a supporting technology in several image-processing tasks. Due to rich semantic information contained in the images, it is very popular for an image to have several labels or tags. This paper aims to develop a novel multi-label classification approach with superior performance.

Many multi-label classification problems share two main characteristics: label correlations and label imbalance. However, most of current methods are devoted to either model label relationship or to only deal with unbalanced problem with traditional single-label methods. In this paper, multi-label classification problem is regarded as an unbalanced multi-task learning problem. Multi-task least-squares support vector machine (MTLS-SVM) is generalized for this problem, renamed as multi-label LS-SVM (ML²S-SVM).

Experimental results on the emotions, scene, yeast and bibtex data sets indicate that the ML²S-SVM is competitive with respect to the state-of-the-art methods in terms of Hamming loss and instance-based F1 score. The values of resulting parameters largely influence the performance of ML²S-SVM, so it is necessary for users to identify proper parameters in advance.

On the basis of MTLS-SVM, a novel multi-label classification approach, ML²S-SVM, is put forward. This method can overcome the unbalanced problem but also explicitly models arbitrary order correlations among labels by allowing multiple labels to share a subspace. In addition, the multi-label classification approach has a wider range of applications. That is to say, it is not limited to the field of image classification.

Using the conservation of resources (COR) theory, the present study aims to examine the role of participative leadership in frontline service employees (FLEs)’ service recovery performance. The present study also tests FLEs’ role breadth self-efficacy (RBSE) as a theoretically relevant mediator and FLE trait mindfulness as an important moderator.

Data were collected using time-lagged (three rounds, two weeks apart) from two sources (193 FLEs and 772 customers, who experienced a service failure). Structural equation modeling (Mplus, 8.6) was employed to analyze the data.

The results revealed that participative leadership was positively associated with FLEs service recovery performance, both directly and indirectly, via RBSE. The results also showed that FLE trait mindfulness moderated the link of participative leadership with RBSE and the indirect association of participative leadership with service recovery performance, via RBSE.

This study suggests that organizational leaders who exhibit participative leadership behavior are valuable for organizations. By demonstrating such behaviors, they boost FLEs' RBSE, which in turn improves their service recovery performance.

The present work makes important contributions to the literature on service recovery performance by foregrounding two important yet overlooked antecedents (participative leadership and RBSE) of FLE service recovery performance. The present work also contributes to the nascent literature on the antecedents and outcomes of RBSE in service contexts.

The purpose of this paper is to present a conceptual model for coding and dissemination of data associated with historical photographic archives. The model is based on Linked Open Data technology and seeks to exhaustively represent the most relevant characteristics for the tasks of contextualization of the documentary groupings and units, management, document retrieval, dissemination and sharing of data about the historical photographs.

An OWL ontology, called Ontophoto, was constructed following an adaptation of the methodology proposed by Uschold and Gruninger and Gruninger and Fox. The ontology was implemented using Protégé 5.5 software. Next a Graph DB® graph database application (Ontotext) was created to generate a query system based on the SPARQL language. To validate the consistency and effectiveness of the model and ontology, a competency questions methodology has been applied using a sample from the Skogler photographic archive.

The model facilitates the generation of systems for dissemination and retrieval of iconographic data for historical research, overcoming some of the limitations with respect to the design of methods of content and contextual information representation for heritage photographic archives.

This study is based on a sample. Future work should consider the implementation of the model on the totality of a photographic collection.

This paper presents a comprehensive ontological model that allows the creation of distributed systems of knowledge representation, which can be queried through SPARQL language.

Management commitments (MCs) have a prominent effect to create a safe work environment in the industries. Though there have been various studies on the prevalence and associated factors of OHS in Ethiopian manufacturing industries, the role of MCs in improving workplace safety, however, has not been studied so far. The purpose of this paper is, therefore, to investigate the role of MCs on improving OHS in iron, steel and metal manufacturing industries (ISMMI) in Addis Ababa.

This paper used a close-ended questionnaire to collect primary data from 89 ISMMI and fitted the data in structural equation modelling (SEM) techniques using SPSS and AMOS.

The major findings of the study showed that directly or indirectly there are good MCs in Ethiopian ISMMI. To some extent, MCs have also resulted in reducing risk and diseases causing factors, which subsequently reduced occupational risks and disease. However, the study showed that MCs are not strategically supported.

Due to the limited scope of data collection, the research results may not be equally implemented outside Addis Ababa and other sectors.

The findings of the research may help policymakers and managers to strictly control MCs and follow up implementation of OHS policies.

This paper is the first of its kind in developing the conceptual framework model and attempting to assess MCs using structural equation model towards improving OHS in ISMMI.

The purpose of this study is to reduce the semantic distance by proposing a model for integrating indexes of textual and visual features via a multi-modality ontology and the use of DBpedia to improve the comprehensiveness of the ontology to enhance semantic retrieval.

A multi-modality ontology-based approach was developed to integrate high-level concepts and low-level features, as well as integrate the ontology base with DBpedia to enrich the knowledge resource. A complete ontology model was also developed to represent the domain of sport news, with image caption keywords and image features. Precision and recall were used as metrics to evaluate the effectiveness of the multi-modality approach, and the outputs were compared with those obtained using a single-modality approach (i.e. textual ontology and visual ontology).

The results based on ten queries show a superior performance of the multi-modality ontology-based IMR system integrated with DBpedia in retrieving correct images in accordance with user queries. The system achieved 100 per cent precision for six of the queries and greater than 80 per cent precision for the other four queries. The text-based system only achieved 100 per cent precision for one query; all other queries yielded precision rates less than 0.500.

This study only focused on BBC Sport News collection in the year 2009.

The paper includes implications for the development of ontology-based retrieval on image collection.

This study demonstrates the strength of using a multi-modality ontology integrated with DBpedia for image retrieval to overcome the deficiencies of text-based and ontology-based systems. The result validates semantic text-based with multi-modality ontology and DBpedia as a useful model to reduce the semantic distance.

Logistics play a vital role in today's economy. As the critical component in the supply chain, logistics is a sector able to be translated as a competitive weapon to the businesses and the nation. Malaysia is a developing country which, laid in the middle of the trade route between west and east, constantly eyes the opportunity to exploit the logistics sector as a platform to bring out its domestic products to the international market and to bring in investment from the global players. Good transport infrastructure and conducive business environment are the ingredients for positioning Malaysia as a hub of logistics activities at the regional and global level. One of the initiatives to achieve the objective is the commencement of Digital Free Trade Zone as a regional e-commerce e-fulfillment hub and drive export of Malaysian SME via e-commerce. As the government is looking toward shifting manufacturing approaches from labor-intensive to capital-intensive strategy, the container ports and airports are equipped with the state-of-the-art technology to ensure efficient movement of cargoes and passenger at the terminal. The progress of logistics and transport activities in Malaysia, coupled with recent development in the commercial and business-related projects, maybe becoming the most important reasons why the foreign investor should consider investing in Malaysia.

This study motivated by humanistic care aims to identify hospitality frontline employees’ alienation in Taiwan during the COVID-19 pandemic, and based on the job demands-resources (JD-R) model, the mediating role of alienation between job characteristics and organizational citizenship behavior (OCB) is discussed.

The authors drew on the JD-R model to delineate the mechanisms by which job demands (including emotional dissonance and work–home conflict) and job resources (including job support, training and possibility for career development) affect OCB through employees’ alienation. This study adopted snowball sampling and purposive sampling to conduct a questionnaire survey aimed at Taiwanese hospitality frontline employees. A total of 373 valid questionnaires were retained, and structural equation model was used to test the research hypotheses.

The results revealed that job demands of emotional dissonance and work–family conflict positively affect alienation; job resources of job support, training and possibility for career development negatively affect alienation; alienation negatively affects OCB; and alienation mediates the relationship between job characteristics and OCB fully.

Considering that alienation plays a full mediating role between job characteristics and organizational outcomes, this study put forward specific suggestions on how to increase job resources and reduce job demands to weaken alienation and further improve organizational performance in management practices. And practical implications were provided to help hospitality human resource management deal with the issue of talents retention. In addition, “work authenticity” should be introduced as a mediator in the future research. “Work authenticity” reflects employees’ positive working life state and is the opposite of “alienation.” The effectiveness of employees’ positive and negative working life state in communicating job characteristics and organizational outcomes can be compared.

The specific alienation experience of hospitality frontline employees is defined. Moreover, by introducing the alienation theory, this study demonstrates the health impairment path of JD-R model and suggests that job characteristics affect OCB through the full mediation of alienation.

本研究以人文关怀为动机, 明确了COVID-19疫情期间台湾酒店一线员工的异化状态, 并基于工作需求-资源理论模型, 探讨了异化在工作特性与组织公民行为之间发挥的中介作用。

笔者运用工作需求-资源模型以阐释工作需求（包括情绪失调和工作-家庭冲突）和工作资源（包括工作支持、培训和职业发展潜能）透过员工的异化影响组织公民行为的机制。本研究采用滚雪球抽样和目的性抽样的抽样方式, 对台湾酒店一线员工开展问卷调查; 留存有效问卷373份, 并采用结构方程模型对研究假设进行检验。

本研究揭示了情绪失调和工作-家庭冲突的工作需求正向影响异化; 工作支持、培训和职业发展潜能的工作资源对异化产生负面影响; 异化对组织公民行为产生负面影响; 异化在工作特性与组织公民行为的关系中起完全中介作用。

综合异化在工作特性与组织成果之间起着完全的中介作用, 本研究就管理实践中如何增加工作资源和减少工作需求以减弱异化并进一步提高组织绩效提出了具体建议, 以此帮助酒店人力资源管理部门处理留住人才的问题。此外, 应引入反映员工积极工作状态的“工作真实性”（即“异化”的对立面）作为中介, 比较员工积极和消极工作状态在沟通工作特性和组织成果上的有效性。

本研究明确了酒店一线员工具体的异化体验。此外, 透过引入异化理论, 本研究实证了工作需求-资源模型的健康损害路径, 并揭示了工作特性通过异化的完全中介作用影响组织公民行为。

Este estudio motivado por la atención humanística identificó la alienación de los empleados de primera línea de la hostelería en Taiwán durante la pandemia de COVID-19 y, basándose en el modelo de exigencias laborales-recursos (JD-R), se analizó el papel mediador de la alienación entre las características laborales y el comportamiento de ciudadanía organizacional fue discutido.

Nos basamos en el modelo JD-R para delinear los mecanismos por los que las exigencias del puesto de trabajo (incluida la disonancia emocional y el conflicto entre el trabajo y el hogar) y los recursos del puesto de trabajo (incluido el apoyo laboral, la formación y la posibilidad de desarrollo profesional) afectan a la organización. Del comportamiento ciudadano (OCB) a través de la alienación de los empleados. Este estudio adoptó el muestreo de bola de nieve y el muestreo intencional para realizar una encuesta por cuestionario dirigida a los empleados de primera línea de la hostelería taiwanesa. Se obtuvieron 373 cuestionarios válidos y se utilizó un modelo de ecuaciones estructurales para probar las hipótesis de la investigación.

Los resultados revelaron que las demandas laborales de disonancia emocional y conflicto trabajo-familia afectan positivamente a la alienación; los recursos laborales de apoyo al trabajo, formación y posibilidad de desarrollo profesional afectan negativamente a la alienación; la alienación afecta negativamente al comportamiento de ciudadanía organizacional; la alienación media totalmente la relación entre las características laborales y el comportamiento de ciudadanía organizacional.

Teniendo en cuenta que la alienación desempeña un papel mediador total entre las características del puesto de trabajo y los resultados organizativos, este estudio presentó sugerencias específicas sobre cómo aumentar los recursos del puesto de trabajo y reducir las exigencias del mismo para debilitar la alienación y mejorar aún más el desempeño organizacional en las prácticas de gestión. Y se aportaron implicaciones prácticas para ayudar a abordar la cuestión de retención de talentos en la gestión de los recursos humanos en la hostelería. Además, la “autenticidad del trabajo” debería introducirse como mediador en la investigación futura. La “autenticidad laboral” refleja el estado de vida laboral positivo de los empleados y es lo contrario de la “alienación”. Se puede comparar la eficacia del estado de vida laboral positivo y negativo de los empleados en la comunicación de las características del trabajo y los resultados organizacionales.

Se define la experiencia específica de alienación de los empleados de primera línea de la hostelería. Además, mediante la introducción de la teoría de la alienación, este estudio demuestra la trayectoria de deterioro de la salud del modelo JD-R, y sugiere que las características del puesto de trabajo afectan al comportamiento de ciudadanía organizacional a través de la mediación total de la alienación.

The purpose of this paper is to find the impact of various design variables on the composite shaft, and also the effect of newly developed resin (NDR) on the strength of the fibers of the composite shaft.

The Taguchi method is used to optimize the design variables. Also, GRG approach is used to validate the result.

NDR improves the bonding strength of fiber than the epoxy resin. With the grey relational analysis (GRA) method, the initial setting (A1B4C4D1) was having grey relational grade 0.957. It was enhanced by using a new optimum combination (A2B2C4D2) to 0.965. It indicates that there is an enhancement in the grade by 0.829 percent. Thus, using the GRA approach of analysis, design variables have been successfully optimized to achieve improved dynamic properties of hybrid composite shaft.

The findings of this research are helping to optimize the design variables for the composite shaft. Also, the NDR gives the good bonding strength of carbon/glass fibers in dynamic loading condition than the epoxy resin.