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The purpose of this paper is to examine the implementation of the verified gross mass (VGM) rules in Hong Kong.

The purpose of this paper is to compare the IMO Guidelines and the Guidelines produced by the Marine Department in Hong Kong.

The drafting of the Hong Kong Guidelines is not as clear and detailed as the International Maritime Organization (IMO) Guidelines.

Shipping companies should review their sea carriage contracts to see whether new clauses should be inserted to solve problems arising from the VGM requirement.

A research by direct analysis of the IMO and the Hong Kong Guidelines on the implementation of the VGM rules in the Safety of Life at Sea (SOLAS) is shown in this paper.

It is commonly known that numerous incidents of container security failure are detected on a daily basis for which nobody is held legally liable. This state of affairs is essentially due to the shippers providing erroneous information, either inadvertently or by design. However, none of the stakeholders such as the carrier, the port operator, the inland transporter or the dry port operator are saddled with the legal responsibility of verifying the correctness of the information provided by the shippers or moving against them legally for misrepresentation of facts.

This paper discusses the issue of container security from a legal perspective with a specific focus on the liability for security failure. While discussing the reasons for non-development of a globally standardized legal regime for container security, this paper also endeavors to suggest possible solutions for the abysmal state of affairs.

This state of affairs persists despite the shipper being saddled with the additional responsibility of providing documentary evidence of verified gross mass of the cargo stuffed in the container by International Maritime Organization.

There is apparently no visible legal action that appears to have been taken against the culprit responsible for the security failure. Thus, the loopholes in the existing legal regime are exploited by all concerned for commercial reasons.

This study proposes practical digitalization strategies and well-grounded evaluation criteria for maritime container supply chains.

The authors identified the status of supply chain digitalization of the Port of Busan in South Korea and developed three digitalization strategies based on industry requirements and consultations with port experts. The authors proposed 11 evaluation criteria for examining the main digitalization strategies in the supply chain operations reference model, based on a survey among 46 experts and used multi-criteria decision-making approaches to prioritize the strategies and evaluation criteria.

The results delineate the status of the digitalization of a real-world port-focal supply chain. The model can be successfully customized to include well-grounded evaluation criteria for digitalization strategies, and presents a practical way to advance the supply chain digitalization strategies. Based on the survey and evaluation, the authors find that increasing data accessibility and improving quality are preferred to adopting a data and information sharing platform.

As the study is limited to the Port of Busan, future case studies could be undertaken to container supply chains driven by different regional ports.

Stakeholders, such as truckers, terminal operators, and shipping liners, might consider the proposed strategies and evaluation criteria when digitalizing their supply chains.

By identifying the needs and specifications of maritime container supply chain digitalization strategies, developing evaluation criteria, and conducting a case study for proof of concept, the study proposes an operational management process with practical, real-world benefits for port-focal supply chains.

Previous literature dealing with sustainable marketing in a B2B context is mostly limited to spot measures on an environmental, economic or social layer. Thus, the purpose of this paper is to exemplify how seaports as powerful economic business networks can facilitate multi-layered sustainability.

The authors integrate multiple case studies to pursue an inductive research approach to derive general patterns based on empirical observations.

Operationalizing the concept of a port community enables the authors to show how seaports not only facilitate multi-layered sustainability but also mutually interact. Hence, port sustainability can be achieved through and by a port community.

The conceptualization of the interplay between port community and multi-layered sustainability contributes to the business and industrial marketing literature in general and to the yet hitherto scarce port marketing literature in particular. Future research should go beyond this initial conceptualization by gathering further empirical research.

The study outlines how strengthening interactions among port management stakeholders (i.e. business and non-business actors such as port authorities and policymakers) might lead to higher economic success and societal welfare by pooling yet hitherto independent resources.

To the best of the authors’ knowledge, this is the first study to define how the concept of a holistic port community can facilitate sustainability acted out on its three pillars and how both concepts interact.

This paper aims to unearth the essential components of Six Sigma for successful deployment and sustainment of service quality in four different organizations in the United Arab Emirates (UAE). More specifically, the paper is intended to determine the motivation to apply Six Sigma, Voice of Customer, Key Performance Indicators (KPIs), Critical-to-Quality (CTQ), readiness factors, Critical Success Factors, sustainment measures, tools and techniques used, challenges/barriers and performance impact on the company.

An exploratory research methodology with multiple case study analyses was adopted to determine the answers to the research objectives. Four case studies from different service processes of four companies were analyzed. The case studies were collated from these companies via a case study protocol with pre-defined criteria.

The analysis shows that service operation improvement projects are primarily dependent on the voice of the internal customer, with return on investment in savings as the KPI of the process. Most organizations prefer cycle time and errors as the CTQs in the Six Sigma projects. Even novice users can effectively apply the Six Sigma methodology with external experts’ assistance, mentoring and interventions. Across the case studies, it is observed that the projects were successfully deployed due to the support of top management leadership, effective communication and cross-functional teams. Employee resistance to change is the common barrier observed during the case study analysis. Eventually, in all the four case studies, Six Sigma is executed with standard tools and techniques within the define, measure, analyze, improve, control (DMAIC) approach.

The present study’s findings cannot be generalized due to the limited number of case study analyses in different ecosystems in the UAE. The authors would like to analyse and report more case studies in service quality improvement through the Six Sigma methodology to comprehend and develop a generic roadmap for the deployment of Six Sigma in the UAE service industry.

The study’s findings provide insights into commonalities and differences between the essential factors of Six Sigma deployment and sustainability in UAE companies.

The study results might help the policymakers and key decision makers in UAE and other countries understand the effectiveness of Six Sigma in service quality improvement with its essential factors for deployment.

China has invested massively in higher education, reaching a mass system, envisaging, as a next step, reaching a universal system. Brazil is still an elite system but needs to create adequate public policies to migrate to a mass system. The purpose of this article is to analyze the paradigms for a mass educational system, with regard to the quality of education offered, and the prospects for achieving a universal system, with Brazil and China as a reference.

The author applied an exploratory and qualitative method, through categorical content analysis. The data were collected through nine interviews with government managers, 15 unstructured (open) questionnaires to specialists in higher education and four student leadership.

The results indicate that the change from an elite system to a mass system impacts quality, as there is an inevitable change in experience. However, this modification does not testify against the mass system, as it is necessary for a nation to pass through it and structure itself adequately in order to reach the universal system, a path desired by both countries.

The study presented the reflections observed by the migration from the elite system to the mass system from the main stakeholders of the system in China and the prospects for Brazil to become a mass system. Additionally, it presented the perspectives for both countries to achieve the desired universal system.

The paper aims to establish a comprehensive optimization analysis model for a helicopter roll on the ground and take off based on optimal control method. The trajectory and control of the entire process are studied, and the key factors affecting the helicopter takeoff distance are analyzed.

First, based on the equivalent stiffness and damping, the landing gear model is established, and a six-degree-of-freedom helicopter model is formed. Then, the simulation of the roll-on takeoff is transformed into a nonlinear optimal control problem (NOCP). Meanwhile, a hybrid single-multiple shooting method-based transcription process is used for discretizing the problem, leading to a finite nonlinear programming model, which is solved by sequential quadratic programming. Finally, the process was calculated and compared with flight test data, which verified the feasibility of the NOCP. The influence of takeoff weight, takeoff power and liftoff airspeed on the takeoff distance of the helicopter was analyzed.

The results show that the takeoff weight can be increased by 17% under the maximum takeoff power, which is roll-on takeoff at an altitude of 0 m. When the helicopter takes off with the maximum weight at an altitude of 5000 m, the liftoff airspeed should be over 49.2 km/h.

The novelty of this paper lies in the comprehensive consideration of helicopter taxiing and taking-off phases, and the application of optimal control theory to establish a comprehensive analysis model, which can quickly analyze the maximum takeoff weight, takeoff distance, optimal liftoff speed and so on. Meanwhile, the method is verified based on the flight data.

The purpose of this study is to measure the mass diffusion coefficient of nitrogen in jet fuel using digital holography interferometry for cost-effective designing and modeling of the aircraft tank inerting system.

The mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels were measured by digital holography interferometry at temperatures ranging from 278.15 to 343.15 K. The Arrhenius equation is used to adequately describe the relationship between mass diffusion coefficients and temperature. The viscosities of RP-3 and RP-5 jet fuels were also measured to examine the accuracy of the Stokes–Einstein model in calculating mass diffusion coefficients.

As temperature increases from 278.15 to 343.15 K, the mass diffusion coefficients increase 4.23-fold for N₂ in RP-3 jet fuel and 5.13-fold for N₂ in RP-5 jet fuel. The value of Dµ/T is not constant as the Stokes–Einstein equation expressed, but is a weak linear function of temperature.

A more accurate diffusion model is proposed by fitting the measured Dµ/T with the temperature and calculating the mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels within 10 per cent relative deviation.

A measurement system for mass diffusion coefficients of N₂ in RP-3 and RP-5 jet fuels was constructed based on the digital holography interferometry. The mass diffusion coefficient can be expressed by a uniform polynomial function of temperature and viscosity.

The purpose of this paper is to characterise the effects of mission and performance parameters on the design space of low observable subsonic unmanned combat aerial vehicles (UCAVs) operating in typical Hi-Lo-Hi ground strike missions.

Conceptual design methodologies appropriate to low observable, tailless UCAVs have been integrated into a multidisciplinary aircraft design environment, GENUS, developed at Cranfield University’s aircraft design group. A basic Hi-Lo-Hi mission is designed and a baseline configuration is established through the GENUS framework. Subsequently, an evolutionary optimiser and a robust gradient-based optimiser are used to obtain convergent design solutions for various leading edge sweep angles, mission ranges, cruise Mach numbers and other operational constraints.

The results indicate that performance constraints, specifically in the form of specific excess power (SEP), have a large influence on the overall sizing of subsonic tailless UCAVs. This requirement drives the engine sizing, which represents a considerable proportion of the empty and gross mass of the vehicle. Cruise Mach number studies show that no significant advantages exist for operating at low speeds while maintaining performance requirements consistent with combat missions. There is a drastic increase in the vehicle’s mass and thrust requirements for flight speeds above Mach 0.8, with low sweep configurations showing a more pronounced effect. Increases in the range are not overly dependent on the leading edge sweep angle. Top-level radar cross section (RCS) results also favour configurations with higher leading edge sweep angles, especially from the nose-on aspect. Finally, research and development costs are shown to be directly linked to engine size.

This research shows the use of an integrated aircraft design environment that incorporates aerodynamics, performance, packaging and low observability aspects into the optimisation loop. Through this methodology, this study supports the efforts towards characterising and establishing alternate visions of the future of aerial warfare through the use of low cost, survivable unmanned platforms in network-centric cooperative tasks.

The purpose of this study is to propose a torque vectoring control system for improving the handling stability of distributed drive electric buses under complicated driving conditions. Energy crisis and environment pollution are two key pressing issues faced by mankind. Pure electric buses are recognized as the effective method to solve the problems. Distributed drive electric buses (DDEBs) as an emerging mode of pure electric buses are attracting intense research interests around the world. Compared with the central driven electric buses, DDEB is able to control the driving and braking torque of each wheel individually and accurately to significantly enhance the handling stability. Therefore, the torque vectoring control (TVC) system is proposed to allocate the driving torque among four wheels reasonably to improve the handling stability of DDEBs.

The proposed TVC system is designed based on hierarchical control. The upper layer is direct yaw moment controller based on feedforward and feedback control. The feedforward control algorithm is designed to calculate the desired steady-state yaw moment based on the steering wheel angle and the longitudinal velocity. The feedback control is anti-windup sliding mode control algorithm, which takes the errors between actual and reference yaw rate as the control variables. The lower layer is torque allocation controller, including economical torque allocation control algorithm and optimal torque allocation control algorithm.

The steady static circular test has been carried out to demonstrate the effectiveness and control effort of the proposed TVC system. Compared with the field experiment results of tested bus with TVC system and without TVC system, the slip angle of tested bus with TVC system is much less than without TVC. And the actual yaw rate of tested bus with TVC system is able to track the reference yaw rate completely. The experiment results demonstrate that the TVC system has a remarkable performance in the real practice and improve the handling stability effectively.

In view of the large load transfer, the strong coupling characteristics of tire , the suspension and the steering system during coach corning, the vehicle reference steering characteristics is defined considering vehicle nonlinear characteristics and the feedforward term of torque vectoring control at different steering angles and speeds is designed. Meanwhile, in order to improve the robustness of controller, an anti-integral saturation sliding mode variable structure control algorithm is proposed as the feedback term of torque vectoring control.