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The purpose of this paper is to investigate the effect of corrugation, wave number, initial stress and the heterogeneity of the media on the phase velocity of the Love-type wave. Moreover, the paper aims to have a comparative study of the presence and absence of anisotropy, heterogeneity, corrugation and initial stress in the half-space, which serve as a focal theme of the study.

The present paper modelled the propagation of the Love-type wave in a corrugated heterogeneous monoclinic layer lying over an initially stressed heterogeneous transversely isotropic half-space. The method of separation of variables is used to procure the dispersion relation.

The closed form of dispersion relation is obtained and found to be in well agreement to the classical Love wave equation. Neglecting the corrugation at either of the boundary surfaces, expressions of the phase velocity of the Love-type wave are deduced in closed form as special cases of the problem. It is established through the numerical computation of the obtained relation that the concerned affecting parameters have significant impact on the phase velocity of the Love-type wave. Also, a comparative study shows that the anisotropic case favours more to the phase velocity as comparison to the isotropic case.

Although many attempts have been made to study the effect of corrugated boundaries on reflection and refraction of seismic waves, but the effect of corrugated boundaries on the dispersion of surface wave (which are dispersive in nature) propagating through mediums pertaining various incredible features still needs to be investigated.

Island attack and defense, emergency rescue, scientific research, civilian fisheries and other fields are inseparable from timely, high-quality underwater communications. However light and other electromagnetic waves are severely attenuated in water, acoustic is currently the only energy carrier that can transmit signals over long distances in water. However, the complex water environment and serious interference bring serious challenges to underwater activities using underwater acoustic sensors-hydroacoustic transducers. Thus, this paper aims to develop a class of high reception sensitivity hydroacoustic transducer structures to provide research and utilization ideas for related scholars.

The electromechanical coupling coefficient is improved by converting the thickness vibration mode of the piezoelectric ceramic into the longitudinal vibration mode of the piezoelectric pillars array, and no polymer is added between the piezoelectric pillars array to reduce lateral coupling as well as internal friction, which can thus reduce the energy losses. Radial stacking in parallel can also enhance the charge generated through the positive piezoelectric effect. The optimal parameters of the structure are determined by equivalent circuit method and finite element analysis, and a hydroacoustic transducer of this structure is fabricated finally.

According to the standard test procedure, the hydroacoustic transducer was tested in water. The tests show that the conductance curve of the stacked high-sensitivity hydroacoustic transducer tested in the air is in good agreement with the simulation results. The resonant frequency is about 118 kHz, and the receiver sensitivity is −166 dB. The stacked material hydroacoustic transducer is in the high-frequency range and has a much higher sensitivity (−166 dB) than many types of hydroacoustic transducers fabricated by piezoelectric ceramic (less than −200 dB).

Although the stacked high-sensitivity hydroacoustic transducer that the authors have fabricated has a performance improvement, it has a limitation. The hollow design of the pillar arrays increases the reception stress on each pillar, and the imposed pressure comes from water also increases simultaneously, so the depth of water that the stacked high-sensitivity hydroacoustic transducer can operate in may be slightly shallower than that made of a pure piezoelectric ceramic block or a piezoelectric ceramic material with polymer added. This will be a problem to be solved in a future deployment.

Whether it is marine scientific research or in various fields such as civil recreation and fishing, hydroacoustic communication and necessary underwater exploration are indispensable for acoustic waves. The hydroacoustic transducer is the sensor that sends and receives sound waves, so a lot of water equipment, such as yachts, sonar buoys, and so on, cannot be separated from the hydroacoustic transducer. In addition, the complexity of the water environment also requires a good performance of the hydroacoustic transducer to facilitate the convenience and effectiveness of subsequent signal processing. Therefore, hydroacoustic transducers have great market and commercial value.

Hydroacoustic transducers are not only of great commercial value but also have a significant impact on the military as well as on people’s livelihood. As we all know, in the area of submarine communication and underwater exploration, sonar is the main force. The performance of the hydroacoustic transducer directly affects the performance of the hydroacoustic signal processing system, and ultimately directly determines the success or failure of the mission. In addition, the large-scale replacement of hydroacoustic transducers on equipment requires the concerted efforts of a large number of practitioners, such as material scientists, structural scientists, mathematicians and so on. Therefore, the rise of hydroacoustic transducers has given rise to a large number of learning positions as well as employment positions.

To enhance the reception sensitivity of the hydroacoustic transducer, the authors have optimized the existing hydroacoustic transducer materials and structures to propose a stacked sensitive element, which can effectively enhance the electromechanical conversion coefficient of the piezoelectric material. Furthermore, the authors have manufactured a hydroacoustic transducer using the proposed stacked sensitive element. The test results of the hydroacoustic transducer also show that the designed stacked sensitive element is of great help to enhance the reception sensitivity of the hydroacoustic transducer.

A popular production model for high-tech manufacturers is that they move most production lines abroad to produce formal products for sale and just keep a few production lines in headquarters to manufacture sample products for new product development. Under such a production model, the paper aims to develop a selection model of International Air Express (IAE) for high-tech manufacturers in airfreight of sample products using the fuzzy best-worst method (BWM).

In this paper, an assessment model based on the fuzzy BWM approach is proposed for high-tech manufacturers in selecting airfreight carriers for the shipping of sample products. Further, one high-tech electronic manufacturer in Taiwan was empirically investigated to validate the assessment model.

The result indicates that electronics manufacturer pays more attention to Promptness, Mutual trust, Freight rate and Financial status of fixed assets when selecting IAEs. Besides, FedEx is argued to be the most preferred IAE for the transportation of sample products. Based on the findings, some practical management implications were discussed.

Some literature limitations should be addressed. Initially, the adoption of the fuzzy BWM assumes independence among criteria. Nonetheless, this assumption is not yet to confirm in this study. Accordingly, this limitation leaves room for improvement in future studies. Further, in this paper, five experienced experts from the Radiant Opto-Electronics Corporation (ROEC) case were empirically surveyed. To ensure the validity of the surveying, this paper adopted an interviewing survey instead of a traditional mailed survey. However, more representative samples are still necessary to confirm the empirical results in future research.

Firstly, the proposed research model provides a systematic framework to the decision-making process, which assists high-tech manufacturers in identifying the most suitable IAEs based on multiple criteria. It has been illustrated that high-tech companies deliver their sample products requiring timely and secure means of transport. In practice, manufacturers can assess various IAEs considering some main factors, such as Operational Flexibility (OF), Partner Relationship (PR), Transportation Capability (TC) and Management, using fuzzy BWM. This process ensures the selection of IAEs aligning with their logistical needs and business priorities, ultimately enhancing operational efficiency and customer satisfaction. Secondly, empirical results from the ROEC case indicate that electronics manufacturer pays more attention to Promptness, Mutual trust, Freight rate and Financial status of fixed assets when selecting IAEs. Besides, FedEx is argued to be the most preferred IAE for transportation of sample products. In other words, ROEC should consider establishing long-term contracts with preferred IAEs (i.e. FedEx) to secure favorable rates and service commitments. On top of that, results not only provide practical information for manufacturers in selecting IAEs but also for IAE partners to improve their service policies.

The results not only provide practical information for high-tech manufacturers in selecting airfreight carriers but also for the airfreight carriers to improve their service quality.

Mobile devices, through their capacity to enable anytime-anywhere learning as well as capture, annotate and share multimedia, offer entirely new ways for students to learn. This chapter provides review of mobile learning with a particular focus on learning design. First various definitions and characteristics of mobile learning are examined in order to establish a common understanding of its boundaries and meaning. Example uses of mobile learning in schools and higher education are described as a way to provide a more concrete understanding of design possibilities. Benefits of mobile learning are unpacked, as distilled from the literature, including the ability to provide flexible, accessible, authentic, personalized, ubiquitous and seamless learning. Mobile learning issues are also examined, including technical problems, cognitive load issues, distraction, equity and safety. A primary school science and a university pre-service teacher education vignette are described so as to offer a more in-depth illustration of what mobile learning can look like and achieve in practice. Finally, mobile learning research findings and observations are synthesized into recommendations, to inform and guide evidence-based mobile learning design practices. Opportunities for future research and investigation are also discussed.

The idea of implementing supply chain management (SCM) principles for the construction industry was embraced by construction stakeholders to enhance the sector's performance. The analysis from the literature revealed that the implementation of SCM in the construction industry enhances the industry's value in terms of cost-saving, time savings, material management, risk management and others. The construction supply chain (CSC) can be managed using the pull or push system. This chapter also discusses the origin and proliferation of SCM into the construction industry. The chapter revealed that the concept of SCM has passed through five different eras: the creation era, the use of ERP, globalisation stage, specialisation stage and electronic stage. The findings from the literature revealed that we are presently in the fourth industrial revolution (4IR) era. At this stage, the SCM witnesses the adoption of technologies and principles driven by the 4IR. This chapter also revealed that the practice of SCM in the construction industry is centred around integration, collaboration, communication and the structure of the supply chain (SC). The forms and challenges hindering the adoption of these practices were also discussed extensively in this chapter.

There exists an association between Supply Chain Quality Management (SCQM) and supply chain competence. To verify such claims, data was collected from Hong Kong based firms. The data showed in most cases an association could be established between SCQM initiatives and the supply chain competence. Some fi rms with SCQM initiatives tend to perform better in terms of customer service or product quality. Supply chains managers may therefore, perform better when their managerial foci are consistent with recognized dimensions of supply chain quality and excellence. In today’s global economy supply chain management is crucial in achieving organizational effectiveness.