Analysis of Liquid Organic Hydrogen Carrier Systems

Liquid organic hydrogen carriers (LOHCs) provide attractive opportunities for hydrogen storage and transportation. In this study, a detailed examination of the most prominent LOHCs is performed, with a focus on their properties and scope for successful process implementation, as well as catalytic materials used for the hydrogenation and dehydrogenation steps. Different properties of each potential LOHC offer significant flexibility within the technology, allowing bespoke hydrogen storage and transportation solutions to be provided. Among different LOHC systems, dibenzyltoluene/perhydro-dibenzyltoluene has been identified as one of the most promising candidates for future deployment in commercial LOHC-based hydrogen storage and transport settings, based on its physical and toxicological properties, process conditions requirements, availability and its moderate cost. PGM-based catalysts have been proven to catalyse both the hydrogenation and dehydrogenation steps for various LOHC systems, though base metal catalysts might have a potential for the technology.

Optimising the Massive MIMO Downlink in the Presence of Power Amplifier Nonlinearities

<p>Massive MIMO is known for its high level of spectral efficiency in multipath rich environments. We present a detailed Massive MIMO cell system using maximum-ratio transmission (MRT) and zero-forcing (ZF) where energy efficiency is taken into account. This is done through the use of a realistic model of moderate performance and hence moderate cost power amplifiers (PAs) for the base station downlink, which could be applied in a practical Massive MIMO system. In the process of detailing the linear aspects of the Massive MIMO system, results for the normalisation factor and array gain are derived, which as far as the author is aware are original. These results are used to derive an expression to optimise the downlink signal-to-interference-and-noise-ratio (SINR) in a linear system, which is also original as far as the author is aware. A process is outlined to optimise the downlink SINR when nonlinear PAs are used and a simulation of a cell system is performed where the benefits of applying the nonlinear optimisation process are demonstrated.</p>

Optimising the Massive MIMO Downlink in the Presence of Power Amplifier Nonlinearities

<p>Massive MIMO is known for its high level of spectral efficiency in multipath rich environments. We present a detailed Massive MIMO cell system using maximum-ratio transmission (MRT) and zero-forcing (ZF) where energy efficiency is taken into account. This is done through the use of a realistic model of moderate performance and hence moderate cost power amplifiers (PAs) for the base station downlink, which could be applied in a practical Massive MIMO system. In the process of detailing the linear aspects of the Massive MIMO system, results for the normalisation factor and array gain are derived, which as far as the author is aware are original. These results are used to derive an expression to optimise the downlink signal-to-interference-and-noise-ratio (SINR) in a linear system, which is also original as far as the author is aware. A process is outlined to optimise the downlink SINR when nonlinear PAs are used and a simulation of a cell system is performed where the benefits of applying the nonlinear optimisation process are demonstrated.</p>

A Deep-Learning Pipeline for TSS Coverage Imputation From Shallow Cell-Free DNA Sequencing

Cell-free DNA (cfDNA) serves as a footprint of the nucleosome occupancy status of transcription start sites (TSSs), and has been subject to wide development for use in noninvasive health monitoring and disease detection. However, the requirement for high sequencing depth limits its clinical use. Here, we introduce a deep-learning pipeline designed for TSS coverage profiles generated from shallow cfDNA sequencing called the Autoencoder of cfDNA TSS (AECT) coverage profile. AECT outperformed existing single-cell sequencing imputation algorithms in terms of improvements to TSS coverage accuracy and the capture of latent biological features that distinguish sex or tumor status. We built classifiers for the detection of breast and rectal cancer using AECT-imputed shallow sequencing data, and their performance was close to that achieved by high-depth sequencing, suggesting that AECT could provide a broadly applicable noninvasive screening approach with high accuracy and at a moderate cost.

Alleviating the independence assumptions of averaged one-dependence estimators by model weighting

Of numerous proposals to refine naive Bayes by weakening its attribute independence assumption, averaged one-dependence estimators (AODE) has been shown to be able to achieve significantly higher classification accuracy at a moderate cost in classification efficiency. However, all one-dependence estimators (ODEs) in AODE have the same weights and are treated equally. To address this issue, model weighting, which assigns discriminate weights to ODEs and then linearly combine their probability estimates, has been proved to be an efficient and effective approach. Most information-theoretic weighting metrics, including mutual information, Kullback-Leibler measure and the information gain, place more emphasis on the correlation between root attribute (value) and class variable. We argue that the topology of each ODE can be divided into a set of local directed acyclic graphs (DAGs) based on the independence assumption, and multivariate mutual information is introduced to measure the extent to which the DAGs fit data. Based on this premise, in this study we propose a novel weighted AODE algorithm, called AWODE, that adaptively selects weights to alleviate the independence assumption and make the learned probability distribution fit the instance. The proposed approach is validated on 40 benchmark datasets from UCI machine learning repository. The experimental results reveal that, AWODE achieves bias-variance trade-off and is a competitive alternative to single-model Bayesian learners (such as TAN and KDB) and other weighted AODEs (such as WAODE).

Utilization of Wireless Sensor Network to Monitor Citarum River Quality for Milkfish Cultivation in Karawang Regency

The purpose of this research (study) is to demonstrate the superiority of the wireless sensor network (WSN) technology method over the laboratory method in monitoring the water quality of the Citarum River in Karawang. To monitor the Citarum river water quality, government of Karawang regency conducted a test by taking the sample water to the laboratory. It seems to be such a conventional method. With the results of the BOD value obtained from the DLHK data, which is 47.93 mg/L, of course it will be a problem for the development of milkfish. However, an advanced method using Wireless Sensor Network (WSN) technology seems to be an alternative. Basically, this technology can monitor the water quality in real-time using multiple parameters and help cultivators to monitor the water used in milkfish cultivation. Of course WSN technology is more efficient than waiting for laboratory results. Therefore, if this technology is applied, the data will be obtained in real time. Of course the data can be processed and monitored directly to determine the quality of the water used. In terms of cost, this technology can be built at a moderate cost compared to laboratory work.

Monitoring of Energy Data with Seamless Temporal Accuracy Based on the Time-Sensitive Networking Standard and Enhanced μPMUs

In the energy sector, distributed synchronism and a high degree of stability are necessary for all real-time monitoring and control systems. Instantaneous response to critical situations is essential for the integration of renewable energies. The most widely used standards for clock synchronisation, such as Network Time Protocol (NTP) and Precision Time Protocol (PTP), do not allow for achieving synchronised simultaneous sampling in distributed systems. In this work, a novel distributed synchronism system based on the Time-Sensitive Networking (TSN) standard has been validated for its integration in an architecture oriented towards the high-resolution digitisation of photovoltaic (PV) generation systems. This method guarantees a time stamping with an optimal resolution that allows for the analysis of the influence of fast-evolving atmospheric fluctuations in several plants located in the same geographical area. This paper proposes an enhanced micro-phasor measurement unit (μPMU) that acts as a phasor meter and TSN master controlling the monitoring system synchronism. With this technique, the synchronism would be extended to the remaining measurement systems that would be involved in the installation at distances greater than 100 m. Several analyses were carried out with an on-line topology of four acquisition systems capturing simultaneously. The influence of the Ethernet network and the transducers involved in the acquisition process were studied. Tests were performed with Ethernet cable lengths of 2, 10, 50, and 75 m. The results were validated with 24-bit Sigma-Delta converters and high-precision resistor networks specialised in high-voltage monitoring. It was observed that with an appropriate choice of sensors and TSN synchronism, phase errors of less than ±1μs can be guaranteed by performing distributed captures up to 50 kS/s. Statistical analysis showed that uncertainties of less than ±100 ns were achieved with 16-bit Successive Approximation Register (SAR) converters at a moderate cost. Finally, the requirements of the IEEE C37.118.1-2011 standard for phasor measurement units (PMU) were also satisfied. This standard establishes an uncertainty of ±3.1 μs for 50 Hz systems. These results demonstrate the feasibility of implementing a simultaneous sampling system for distributed acquisition systems coordinated by a μPMU.

Heart Function Clinics for Patients With Heart Failure

Low- to moderate-quality clinical evidence suggested that heart failure clinics were associated with significant reductions in all-cause mortality, reductions in heart failure‒related hospitalization, better guideline-directed medical therapy management, and higher adherence to heart failure medications compared to usual care. The findings for all-cause hospitalization were mixed. One low-quality economic study in Denmark found that heart failure clinics were associated with higher costs but no significant difference in mortality rates compared with the usual care. Another moderate cost-effectiveness analysis study in Canada revealed that heart failure clinic interventions were cost-effective compared to standard care, with an incremental cost-effectiveness ratio below the willingness-to-pay threshold.

Wide Bandwidth and Inexpensive Current Sensor for Power Electronics—An Augmented LEM Current Sensor

This paper presents the overall concept of a wideband and cost-effective current sensor. The sensor consists of a paralleled Hall-based current sensor (LEM) and a wideband current transformer (CT). A significant improvement of the band range and the moderate cost of the proposed sensor enable it to be used both to measure the instantaneous value in order to precisely plot the current and to obtain signals for a closed-loop control system of high-frequency power electronic converters. The sensor should be considered as an Augmented LEM Current Sensor (ALCS), which allows it to measure low- and high-frequency current signals. Finally, it allows for the measurement of a bipolar current up to 40 A. The overall cost of the sensor, along with the previously mentioned benefits, is an important feature of the proposed sensor. The present paper presents the analytical concept of the sensor (ALCS), a theoretical approach using simulation analysis, and the experimental results, which clearly demonstrate the wide range of the sensor in dynamic and static measurements.

RESEARCH OF CENTRIFUGAL GRINDER GRANTS

The processes of grinding dry and wet dispersed materials are common in alcohol, beer, sugar, meat, bakery, feed, chemical and a number of other industries, as well as in construction. Relevant for these processes, especially recently, in connection with the rise in the cost of energy resources, is the problem of reducing energy costs during their implementation, subject to high productivity, sufficient degree and uniformity of grinding and moderate cost of equipment for the process. The article proposes scientifically substantiated dependencies for calculating the minimum required electrical power of an experimental industrial grinder, which is considered as a replacement for hammer crushers, when used to grind wet grain of wheat, rye or corn and ensure the specified performance, taking into account the daily volume of raw materials processed at the enterprise. as well as the permissible degree of its refinement. In particular, equations were obtained to determine the power consumption for bringing the raw material in the grinder into rotary motion, for the friction between the grains of the raw material and the grinder discs, as well as the internal surfaces of its working chamber, for the friction between the grains themselves, the power required for grinding. The electric power of the grinder, the effective efficiency (41%) and the total efficiency (14%), by which it is superior to hammer crushers, have been calculated. In this work, based on the theory of contactless hydraulic seals, the analysis of possible trajectories of the particles of the processed raw materials in the working chamber of the grinder (grains of wheat, rye or corn moistened with water) is carried out, the forces acting on the particles of the raw material in the process of their movement from the axis of the grinder to the periphery of the working chamber are determined, as well as the analysis of the interaction of particles during their grinding, based on the theoretical provisions of the mechanics of quasi-solid and quasi-liquid bodies.