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The World Wide Web's search engines are the main tools for indexing and retrieval of Internet resources today. Comparison and evaluation of their performance is of great importance for system developers and information professionals, as well as end‐users, for the improvement and development of better tools. The paper describes categories and special features of Web‐based databases and compares them with traditional databases. It then presents a review of the literature on the testing and evaluation of Web‐based search engines. Different methodologies and measures used in previous studies are described and their findings are summarised. The paper presents some evaluative comments on previous studies and suggests areas for future investigation, particularly evaluation of Web‐based search engines from the end‐user's perspective.

With the advent of the era of Big Data, the scale of knowledge graph (KG) in various domains is growing rapidly, which holds huge amount of knowledge surely benefiting the question answering (QA) research. However, the KG, which is always constituted of entities and relations, is structurally inconsistent with the natural language query. Thus, the QA system based on KG is still faced with difficulties. The purpose of this paper is to propose a method to answer the domain-specific questions based on KG, providing conveniences for the information query over domain KG.

The authors propose a method FactQA to answer the factual questions about specific domain. A series of logical rules are designed to transform the factual questions into the triples, in order to solve the structural inconsistency between the user’s question and the domain knowledge. Then, the query expansion strategies and filtering strategies are proposed from two levels (i.e. words and triples in the question). For matching the question with domain knowledge, not only the similarity values between the words in the question and the resources in the domain knowledge but also the tag information of these words is considered. And the tag information is obtained by parsing the question using Stanford CoreNLP. In this paper, the KG in metallic materials domain is used to illustrate the FactQA method.

The designed logical rules have time stability for transforming the factual questions into the triples. Additionally, after filtering the synonym expansion results of the words in the question, the expansion quality of the triple representation of the question is improved. The tag information of the words in the question is considered in the process of data matching, which could help to filter out the wrong matches.

Although the FactQA is proposed for domain-specific QA, it can also be applied to any other domain besides metallic materials domain. For a question that cannot be answered, FactQA would generate a new related question to answer, providing as much as possible the user with the information they probably need. The FactQA could facilitate the user’s information query based on the emerging KG.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Industry practice has shown that technology licensing has an important effect on the R&D cooperation between firms. Different licensing methods will significantly impact a supply chain member's cooperative and price R&D decisions. However, there is scant literature investigating the decision on technology licensing and its impact on a supply chain member's price and cooperative R&D decisions. To address this gap, the authors investigate the R&D cooperation and the technology licensing in a supply chain formed of an original equipment manufacturer (OEM), a contract manufacturer (CM), and a third-party manufacturer which will compete with the OEM when the technology licensing occurs.

The authors investigate two licensing patterns, royalty licensing, fixed fee licensing together with the no licensing, within the R&D cooperative supply chain by developing two three-stage and a two-stage Stackelberg models.

Compare to the no licensing strategy, technology licensing always benefits to the OEM and the society especially when the technology efficiency and the brand power of the third-party manufacturer are more significant; the royalty licensing benefits to the OEM more when the technology efficiency and the brand power of the third-party manufacturer are higher; the fixed fee licensing benefits to the OEM more when the technology efficiency and the brand power of the third-party manufacturer are lower.

The royalty licensing is more effective for mitigating price competition intensity and helping firms to maintain higher sales margins; the fixed fee licensing induces firms' lower sales margins but increases the firms' sales quantities; in most cases, the fixed fee licensing is optimal from the perspectives of consumer and society, however, the CM's investment intention to the R&D technology with the fixed fee licensing is lower.

So far, different licensing models under the R&D cooperation have not been investigated, and the authors propose two three-stage Stackelberg models with considering the competition caused by technology licensing under the R&D cooperation to deal with the cooperative R&D and technology licensing issues.

Hydro-viscous drive (HVD) clutches are widely used in equipment requiring soft start, such as fans and pumps, to transmit torque and adjust speed by changing the gap distance between friction pairs. This paper aims to propose a novel two-parameter evaluation method for HVD during the mixed lubrication stage. The objective is to develop an effective model that establishes the relationship between these parameters and the actual surface topography.

In the presented methods, the fractal features of the real manufacturing surface are calculated based on the power spectrum function by the ultra-depth three-dimensional microscope. After that, the hybrid friction model of the friction plate is established based on mixed elasto-hydrodynamic lubrication theory, boundary friction model and fractal theory. Then the torque and load bearing characteristics of the clutch are obtained, and the influences of the surface fractal features are investigated and discussed. Finally, the Weierstrass–Mandelbrot function is adopted for the surface topography characterization and evaluation.

The results indicate that the proposed method exhibits good accuracy, while the speed difference between the friction pair exceeds 2,500 rpm. It is concluded that this paper proposed a way to evaluate the torque and loading capacity of HVD considering the real manufacturing surface topography and is helpful for surface optimization.

The originality and value of this study lie in its development of a novel torque and load bearing capacity evaluation method for HVD in mixed lubrication stage, considering manufacturing surface topography and describing the real manufacturing surface.

The key purpose of this study was to investigate the effects of different ultrasonic irradiation times on the wettability and other properties of the resulting water-based coating. The subject water-based coating was prepared using water-soluble polyester and amino resins by ultrasonic oscillation.

The coating was prepared by polymerising polyester and amino resins in water using ultrasonic oscillation. The coating was baked for 40 seconds at 350°C to coalesce and solidify the film. The contact angle, thermal stability and mechanical properties of the film, as well as the molecular weight (MW) and structure of the polyester resin, were determined.

The contact angle of the coating was found to decrease with ultrasonic irradiation; the mechanical properties and thermal stability were not altered when the irradiation time was longer than 5 hours. The MW of the polyester initially decreased then increased and stabilized with ultrasonic irradiation. The structure of polyester molecule and aggregated state of the solidified coating were not changed by ultrasonic irradiation.

In the study reported here, the effects of different ultrasonic irradiation times were investigated. Results of this research could benefit in-depth understanding of the influence of ultrasonic treatment on polyester resins and polyester coatings and could further promote the development of water-based coatings.

The contact angle of the water-based coating decreased by mechanical means. The effects of ultrasound on microstructure and properties of the coating and resin were discussed in detail.

The purpose of this study is to simultaneously determine the constitutive parameters and boundary conditions by solving inverse mechanical problems of power hardening elastoplastic materials in three-dimensional geometries.

The power hardening elastoplastic problem is solved by the complex variable finite element method in software ABAQUS, based on a three-dimensional complex stress element using user-defined element subroutine. The complex-variable-differentiation method is introduced and used to accurately calculate the sensitivity coefficients in the multiple parameters identification method, and the Levenberg–Marquardt algorithm is applied to carry out the inversion.

Numerical results indicate that the complex variable finite element method has good performance for solving elastoplastic problems of three-dimensional geometries. The inversion method is effective and accurate for simultaneously identifying multi-parameters of power hardening elastoplastic problems in three-dimensional geometries, which could be employed for solving inverse elastoplastic problems in engineering applications.

The constitutive parameters and boundary conditions are simultaneously identified for power hardening elastoplastic problems in three-dimensional geometries, which is much challenging in practical applications. The numerical results show that the inversion method has high accuracy, good stability, and fast convergence speed.

Market orientation is often mentioned as a key factor for the success of domestic and international activities, but our knowledge about differences in degrees of market orientation remains limited for firms that have varying degrees of international activities. In particular, the literature is very sparse with regard to studies of newly established firms. Our study empirically explores this gap examining how different types of new ventures adopt two strategic components of market orientation – customer orientation and competitor orientation. Our empirical evidence is based on responses from CEOs of 249 Danish manufacturing firms that are categorized into four groups, depending on their degree of international operations within the first three years. We demonstrate that the most internationally oriented firms seem to be the most market oriented in general. They are significantly more competitor-oriented than domestically oriented firms, but the results regarding customer orientation are more mixed. Interestingly, we find indications that the strategic emphasis on customer orientation may be higher for firms with domestic operations than for those with limited international operations. We discuss implications for research and managers.

This chapter attempts to explore customer loyalty and retention in the context of Pakistani restaurants. Effects of customer perceived value and service quality as antecedents are tested on customer loyalty and retention along with the mediating effects of customer satisfaction and customer relationship management quality. This chapter is conducted in 15 restaurants from Multan. Results reveal how the restaurant sector lacks a monitoring mechanism that promotes an effective customer relationship. For example, what kinds of measurements the manager could use to enhance a customer's loyalty and retention.

This research integrates maintenance planning and production scheduling from a green perspective to reduce the carbon footprint.

A mixed-integer nonlinear programming (MINLP) model is developed to study the relation between production makespan, energy consumption, maintenance actions and footprint, i.e. service level and sustainability measures. The speed scaling technique is used to control energy consumption, the capping policy is used to control CO2 footprint and preventive maintenance (PM) is used to keep the machine working in healthy conditions.

It was found that ignoring maintenance activities increases the schedule makespan by more than 21.80%, the total maintenance time required to keep the machine healthy by up to 75.33% and the CO2 footprint by 15%.

The proposed optimization model can simultaneously be used for maintenance planning, job scheduling and footprint minimization. Furthermore, it can be extended to consider other maintenance activities and production configurations, e.g. flow shop or job shop scheduling.

Maintenance planning, production scheduling and greenhouse gas (GHG) emissions are intertwined in the industry. The proposed model enhances the performance of the maintenance and production systems. Furthermore, it shows the value of conducting maintenance activities on the machine's availability and CO2 footprint.

This work contributes to the literature by combining maintenance planning, single-machine scheduling and environmental aspects in an integrated MINLP model. In addition, the model considers several practical features, such as machine-aging rate, speed scaling technique to control emissions, minimal repair (MR) and PM.