Should Indonesia regulate foreign military activities in its EEZ?

The issue of foreign military activities in the exclusive economic zone (EEZ) still divides the international community despite the almost universal acceptance of the 1982 Law of the Sea Convention. As a country with a vast EEZ, Indonesia is considering whether it needs specific legislation to regulate this issue. This article analyses the legal and political considerations of such a crucial intention and argues that under international law, it is difficult to justify regulating foreign military activities in the EEZ. Given strategic partnerships and other pressing issues, this article suggests that Indonesia should maintain the status quo of not regulating such activities

Polymer nanocomposite dielectrics for capacitive energy storage

Owing to their excellent discharged energy density over a broad temperature range, polymer nanocomposites offer immense potential as dielectric materials in advanced electrical and electronic systems, such as intelligent electric vehicles, smart grids and renewable energy generation. In recent years, various nanoscale approaches have been developed to induce appreciable enhancement in discharged energy density. In this Review, we discuss the state-of-the-art polymer nanocomposites with improved energy density from three key aspects: dipole activity, breakdown resistance and heat tolerance. We also describe the physical properties of polymer nanocomposite interfaces, showing how the electrical, mechanical and thermal characteristics impact energy storage performances and how they are interrelated. Further, we discuss multi-level nanotechnologies including monomer design, crosslinking, polymer blending, nanofiller incorporation and multilayer fabrication. We conclude by presenting the current challenges and future opportunities in this field

Effects of annealing on periodic microstructure and mechanical properties of inter-layer hammering hybrid wire arc additively manufactured aluminum alloy

It is common to use heat treatment process to control the microstructure of additive manufacturing parts and improve the mechanical properties. However, there are few reports about the control of microstructure properties of WAAM hybrid inter-layer hammering fabricated parts by heat treatment. In this study, the effect of annealing on microstructure and mechanical properties of inter-layer hammering hybrid wire arc additively manufactured aluminum alloy was studied. The ratio variation of fine grain (FG) and coarse grain (CG) regions, grain size and dislocations were analyzed, and the strength-plasticity mechanism was revealed. The results shown that with the increase of annealing temperature, the ratio of FG and CG region changed from 4:1–1:5, grain growth and recrystallization happened in FG and CG regions, respectively, dislocations mostly retained in FG region and released in CG region. With the introduction of annealing and the increase of annealing temperature, the strength of hybrid manufactured samples gradually weakened while the plasticity first improved and then reduced. The best tensile properties of ultimate tensile stress 366 MPa and elongation 29.2% were achieved at 180 °C annealing. Compared with as-deposited sample, the synergistic enhancement of strength and plasticity in annealed samples is owing to dislocation strengthening, grain refinement, and heterogeneous structural strengthening. Compared with hammered sample, the strength retained and significant improved in plasticity of annealed sample, owing to dislocation released, grain refinement and heterogeneous structural

Enhancing domestic food supply in the UAE: A framework for technology-driven urban farming systems

It is estimated that the recent ongoing supply chain disruptions have forced a transition in the traditional food supply chain business models. Organizations across all sectors are now adopting digital transformation strategies for embracing the new normal. Food security in the United Arab Emirates (UAE) is threatened by country\u27s heavy reliance on food imports. Innovative urban farming systems are anticipated to improve the food security and sustainability to a great extent. Using a survey-based methodology, the present study aims to develop, validate, and apply a multi-dimensional innovative urban food production system framework for UAEs agricultural sector. Based on the data collected from 299 stakeholders across the whole agri-food supply chains in the UAE, the study determines ways of reducing dependency on food imports by scaling up technology-driven and resource-efficient innovative urban farming systems. Data were analysed and the model were moderated using Analysis of MOment Structures (AMOS) and Partial Least Squares- Structural Equation Modelling (PLS-SEM). The findings from the study highlight that digital technology moderates the relationship between innovative urban farming systems and sustainable urban farming. Resource efficiency and conservation practices were positively associated with sustainable urban farming. The study offers several managerial and theoretical insights

TCAD modelling of a-Si:H devices for particle detection applications

Hydrogenated amorphous silicon (a-Si:H) has been proposed as a suitable material for particle detection applications thanks to its property to be deposited over a large area and above a variety of different substrates, including flexible materials. Moreover, the low cost and intrinsic radiation tolerance made this material appealing in applications where high fluences are expected, e.g. in high energy physics experiments. In order to optimize the device geometry and to evaluate its electrical behaviour in different operating conditions, a suitable Technology CAD (TCAD) design methodology can be applied. In this work, carried out in the framework of the HASPIDE INFN project, we propose an innovative approach to the study of charge transport within the material, using the state-of-the-art Synopsys Advanced TCAD Suite. Different custom mobility models have been devised and implemented within the code as external PMI (Physical Model Interfaces), starting from the Poole–Frenkel model and accounting for different dependencies on temperature and internal potential distribution, thus resulting in a new mobility model embedded within the code. Simple test structures, featuring p-i-n diodes have been simulated and compared to experimental data as a benchmark. The overall aim was to account for the effect of different biasing conditions (namely, different electrical potential and electric field distribution within the device) and operating conditions (e.g. temperature). This work fosters the use of commercially available TCAD suite such as Synopsys Sentaurus, largely diffused in the radiation detection scientific community, for the design and optimization of innovative a-Si:H devices for particle detection applications

A comparison of likelihood-based methods for size-biased sampling

Three likelihood approaches to estimation under informative sampling are compared using a special case for which analytic expressions are possible to derive. An independent and identically distributed population of values of a variable of interest is drawn from a gamma distribution, with the shape parameter and the population size both assumed to be known. The sampling method is selection with probability proportional to a power of the variable with replacement, so that duplicate sample units are possible. Estimators of the unknown parameter, variance estimators and asymptotic variances of the estimators are derived for maximum likelihood, sample likelihood and pseudo-likelihood estimation. Theoretical derivations and simulation results show that the efficiency of the sample likelihood approaches that of full maximum likelihood estimation when the sample size n tends to infinity and the sampling fraction f tends to zero. However, when n tends to infinity and f is not negligible, the maximum likelihood estimator is more efficient than the other methods because it takes the possibility of duplicate sample units into account. Pseudo-likelihood can perform much more poorly than the other methods in some cases. For the special case when the superpopulation is exponential and the selection is probability proportional to size, the anticipated variance of the pseudo-likelihood estimate is infinite

Characterisation of synthesised trimetallic nanoparticles and its influence on anaerobic digestion of palm oil mill effluent

The augmentation of biogas production can be achieved by incorporating metallic nanoparticles as additives within anaerobic digestion. The objective of this current study is to examine the synthesis of Fe–Ni–Zn and Fe–Co–Zn trimetallic nanoparticles using the co-precipitation technique and assess its impact on anaerobic digestion using palm oil mill effluent (POME) as carbon source. The structural morphology and size of the synthesised trimetallic nanoparticles were analysed using a range of characterization techniques, such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and Energy-dispersive X-ray spectroscopy (EDX). The average size of Fe–Ni–Zn and Fe–Co–Zn were 19–25.5 nm and 19.1–30.5 nm respectively. Further, investigation focused on examining the diverse concentrations of trimetallic nanoparticles, ranging from 0 to 50 mgL−1. The biogas production increased by 55.55% and 60.11% with Fe–Ni–Zn and Fe–Co–Zn trimetallic nanoparticles at 40 mgL−1 and 20 mgL−1, respectively. Moreover, the lowest biogas of 11.11% and 38.11% were found with 10 mgL-1 of Fe–Ni–Zn and Fe–Co–Zn trimetallic nanoparticles. The findings of this study indicated that the trimetallic nanoparticles exhibited interactions with anaerobes, thereby enhancing the degradation process of palm oil mill effluent (POME) and biogas production. The study underscores the potential efficacy of trimetallic nanoparticles as a viable supplement for the promotion of sustainable biogas generation

Exploring academic perspectives on immersive scheduling in a UK university

This study examined how academic staff responded to a cross-institutional change initiative to integrate immersive scheduling into the first-year undergraduate curriculum. Immersive scheduling, also referred to as block or compressed delivery, sought to create a supportive first-year experience, to ease students’ transition to university. Adopting an immersive approach is associated with considerable change as academic staff adapt their practice to accommodate the compressed time frame of modules and embrace learning and assessment methods associated with this delivery format. In this study, we undertook semi-structured interviews with 17 academics who were leading the development and delivery of immersive modules or supporting the teaching and learning initiative. Our data indicated that academics played a significant role in the acceptance or rejection of the vision for immersive scheduling. Acceptance was reliant on academics recognising value in the vision, and this varied depending on the extent to which it resonated with local practice. In some cases, the move to immersive scheduling represented a valued opportunity to update pedagogic and assessment practices. However, in other contexts, academic resistance led to dilution of key elements of the vision, with compliance rather than innovation being the outcome. This study also highlights the value of using a combination of module delivery formats to mitigate recognised drawbacks associated with immersive delivery. We conclude this paper by proposing recommendations to support the future development of immersive scheduling in higher education institutions

An enhanced consortium blockchain diversity mining technique for IoT metadata aggregation

Over the last two decades, Internet of Things (IoT) networks have grown exponentially. Although the devices have relatively low memory, resource, and processing capability, the trend is that nodes generate a large volume of data. That is where cloud technology comes into play to provide storage space. Because of its centralized nature and robustness, a large network operating with cloud assistance may be vulnerable. Due to rigid access control policies, the devices may be vulnerable to malicious activity. On the other hand, cloud technology provides a platform for such a security system to operate. A centralized secure architecture fails to consider mobile and edge devices within the context of these criteria. This raises numerous concerns about trusting third-party cloud intermediaries, which cause security and privacy leaks. The goal of this research is to look into the problem of blockchain consensus algorithms and their applicability in IoT with cloud-native infrastructure in the Ethereum and MultiChain variants. The significant challenge is scaling the core layer without sacrificing decentralization, security, or public verifiability. This type of testbed is used to investigate the impact of architectural design and consensus models in a lightweight IoT environment. Consensus in each IoT transaction remains the most important aspect of blockchain-enabled IoT networks. When the ledger is updated without privacy protection, transaction-oriented breaches can occur. Current practices for integrating finite IoT network resources into infrastructure-oriented blockchain implementations are flawed due to they are willing to sacrifice data security and integrity in order to save time and energy. This encourages researchers to investigate an improved lightweight block verification approach to the blockchain functional framework, that decreases processing needs, network latency, and network overhead substantially. As a result, the layer-3 consensus promotes blockchain to include the block with a 35% improvement in base layer block time efficiency and a 56% increase in throughput

A metamaterial isolator with tunable low frequency stop-band based on magnetorheological elastomer and magnet spring

This paper proposed and prototyped a metamaterial isolator with periodic structure based on magnetorheological elastomer (MRE) and magnet spring. With acoustic metamaterial structure, the proposed metamaterial isolator can generate a stop-band, which means the vibration over specific frequency can\u27t be transferred and will be isolated effectively. Then, with the control of MRE stiffness, the cut-off frequency of the stop-band is tunable, which makes the isolator potential to be adapted to different working situations. The negative stiffness generated by the magnet spring can help to lower the start frequency of the stop-band and enhance the bearing capacity of the metamaterial isolator in vertical direction in the meantime. To verify the feasibility of the proposed device, the magnetic field simulation was first conducted and discussed, and the negative stiffness property of the magnet spring was numerically measured and demonstrated. Then, the mass-spring model of the metamaterial isolator was established in order to theoretically analyze the influence of MRE and the magnet spring on the vibration attenuation efficiency. A vibration platform was finally set up and the evaluation experiments were conducted to validate the theoretical analysis. In this paper, the structure design, theoretical modelling and experimental results of the metamaterial isolator are comprehensively discussed, which demonstrate that the prototype structure can work well as expected. The design of the metamaterial isolator with negative stiffness magnet spring can also enlighten more studies on lowering the bandgap frequency of the acoustic metamaterial without sacrificing large structure stiffness