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The cabled seafloor observation system possesses the technical advantages of long-term, in-situ, and online monitoring, and it has been widely used for basic marine scientific research, exploration, development and utilization of resources and energy, marine disaster forecasting and warning, marine environmental protection, navigation, and military marine environmental protection. The development status of the cabled seafloor observation system at home and abroad is described and summarized, and analyses of the key technologies, application scenarios, and data derivative services of the cabled seafloor observation system are presented. Specific suggestions for future development are proposed in terms of top-level design, innovative development, differentiated research, and development of the cabled seafloor observation system, as well as expanding the application field of cabled seafloor observation data, so as to provide a useful reference for the development of the seafloor observation system in China.

Abstract Background Non-invasive online fluorescence monitoring in high-throughput microbioreactors is a well-established method to accelerate early-stage bioprocess development. Recently, single-wavelength fluorescence monitoring in microtiter plates was extended to measurements of highly resolved 2D fluorescence spectra, by introducing charge-coupled device (CCD) detectors. Although introductory experiments demonstrated a high potential of the new monitoring technology, an assessment of the capabilities and limits for practical applications is yet to be provided. Results In this study, three experimental sets introducing secondary substrate limitations of magnesium, potassium, and phosphate to cultivations of a GFP-expressing H. polymorpha strain were conducted. This increased the complexity of the spectral dynamics, which were determined by 2D fluorescence measurements. The metabolic responses upon growth limiting conditions were assessed by monitoring of the oxygen transfer rate and extensive offline sampling. Using only the spectral data, subsequently, partial least-square (PLS) regression models for the key parameters of glycerol, cell dry weight, and pH value were generated. For model calibration, spectral data of only two cultivation conditions were combined with sparse offline sampling data. Applying the models to spectral data of six cultures not used for calibration, resulted in an average relative root-mean-square error (RMSE) of prediction between 6.8 and 6.0%. Thus, while demanding only sparse offline data, the models allowed the estimation of biomass accumulation and glycerol consumption, even in the presence of more or less pronounced secondary substrate limitation. Conclusion For the secondary substrate limitation experiments of this study, the generation of data-driven models allowed a considerable reduction in sampling efforts while also providing process information for unsampled cultures. Therefore, the practical experiments of this study strongly affirm the previously claimed advantages of 2D fluorescence spectroscopy in microtiter plates.

This letter proposes an on-state drain-source voltage (${V}_{{\rm{ds,on}}}$) measurement circuit for SiC MOSFETs. The proposed circuit effectively solves the problem of inconsistent diode volt-ampere characteristics through an additional current source. The voltage difference between the two diodes is compensated by adjusting the auxiliary current under the condition of a fixed first current. This circuit does not require diode pre-selection and significantly improves measurement accuracy. The circuit is implemented in a double-pulse test (DPT) of a SiC MOSFET (900 V/23 A, 25 °C). The results show that the circuit has a fast response speed with a delay time of 0.4 μs. Even at the same current, the forward voltage difference between the two diodes reaches 3.32 mV. Compared to measurement results from a six-bit semi-digital multimeter, the measurement error of the proposed circuit is less than 1.5% at different currents and temperatures.

Accurate data is the basis for all marine scientific research. Different from the traditional sampling monitoring process, it is fully automated for marine buoy monitoring from sample collection to data results, and the focus of data quality control is no longer focused on the "sample collection-analysis and testing" . In this study, the quality control system for marine buoy monitoring data through analysis of the buoy data in the past two years was designed, including six items: floating body stability, instrument equipment calibration, system operation and maintenance, data transmission and reception, contrast monitoring, abnormal data determination, and abnormal data determination and contrast monitoring were focused on. This research established a quality control method library, and proposed three levels of abnormal data determination rules for buoy data quality control: valid, credible, and relatively accurate, which was innovative. The first layer is the valid data set obtained after removing the obvious fault values, outliers, and other invalid data; the second layer is the credible data set obtained after screening by various quality control methods from the method library; the third layer is relatively accurate data set verified against field contrast monitoring results. Based on the marine buoy monitoring data in Zhejiang Province, the design ideas and methods of the quality control system for buoy monitoring data were proposed, which would help to improve the quality of the online monitoring data of buoys in the coastal waters of Zhejiang. This design would provide a reference for the national marine buoy monitoring data quality control.

ABSTRAK Danau Toba merupakan danau terbesar di Indonesia yang memiliki peran penting sebagai sumberdaya untuk mendukung potensi ekologis dan ekonomis masyarakat setempat. Akan tetapi, tekanan pencemaran yang diakibatkan oleh aktivitas masyarakat di sekitar danau terus bertambah. Penelitian ini memanfaatkan teknologi ONLIMO yang dikembangkan oleh Pusat Teknologi Lingkungan, Badan Pengkajian dan Penerapan Teknologi untuk meningkatkan kegiatan pemantauan kualitas air di Danau Toba. Penelitian ini bertujuan untuk monitoring kualitas air di Danau Toba dengan menggunakan sistem ONLIMO yang memanfaatkan teknologi telemetri dalam pengaplikasiannya. Data diambil pada bulan Desember 2017, di 2 lokasi stasiun pemantauan yaitu stasiun 1 (STO11 di Toba Marom) dan stasiun 2 (STO12 di Toba Ajibata). Sensor yang digunakan berupa multiprobe sensor yang terdiri dari sensor suhu, DHL, TDS, kekeruhan, pH, DO, Nitrat dan Amonia. Data berasal dari database ONLIMO dan dianalisis dengan menggunakan metode storet. Hasil menunjukkan bahwa di kedua stasiun secara umum tergolong ke dalam perairan yang tercemar ringan, dengan parameter yang berada di atas baku mutu terdiri dari DO, kekeruhan, dan amonia. Penggunaan sistem teknologi ONLIMO dapat mempermudah kegiatan monitoring kualitas air di Danau Toba secara kontinyu. Kata kunci: analisis storet, danau toba, kualitas air, pemantauan online, status mutu air ABSTRACT Lake Toba is the largest lake in Indonesia which has an important role as a resource to support the ecological and economic potential of the local community. However, the pressure caused by community activities around the lake continues to grow. This research utilizes the ONLIMO technology developed by the Center for Environmental Technology, Agency for the Assessment and Application of Technology to improve water quality monitoring in Lake Toba. This study aims to monitor air quality in Lake Toba using the ONLIMO system that utilizes telemetry technology in its application. Data was collected in December 2017, at 2 monitoring locations, namely station 1 (STO11 in Toba Marom) and station 2 (STO12 in Toba Ajibata). The sensor used is a multiprobe sensor consisting of a temperature sensor, DHL, TDS, turbidity, pH, DO, Nitrate and Ammonia. Data were derived from the ONLIMO database and analyzed using the storet method. The results show that both stations are generally classified as lightly polluted waters, with parameters above the quality standards consisting of DO, turbidity, and ammonia. The use of the ONLIMO technology system can facilitate continuous monitoring of water quality in Lake Toba. Keywords: storet analysis, toba lake, water quality, online monitoring, water quality status

The characteristics of tunable diode laser absorption spectroscopy (TDLAS) gas detection technology are high resolution, low detection limit and fast response speed, it has been widely used in on-line monitoring of ambient gases. The gas composition is complex in coal mines. Traditional gas sensors, chromatographic analysis and spectroscopic analysis techniques are limited by the method itself or the environmental conditions on site, and there are different degrees of limitations. Firstly, we introduced the working principles and characters of TDLAS gas detection technology. Secondly, the development process and research status of TDLAS technology in the fields of fire protection, petrochemical, environmental protection and coal mine gas detection are focused on analyzed. Finally, the application effect of this technology in downhole methane gas detection and online monitoring of multiple mixed gases is analyzed.

The estuary is the transition zone between the river and the marine ecosystem. The terrestrial ecological sensitive factors entering the sea will greatly affect the ecological status of the coastal waters. Therefore, monitoring of ecologically sensitive factors entering the sea is an important basis for coastal ecological protection and ecological disaster prevention and mitigation, and is also a key part of promoting the sustainable development of the marine economy. However, the establishment of the ecological early warning and monitoring system for the estuary in China is still in its infancy, and there is still a big gap between it and developed countries. This paper started with the impact of the ecological status of the estuary on the health of the marine ecosystem, summarized the development process, construction and application direction of the marine ecological early warning and monitoring technology in the estuary at home and abroad, and deeply discussed the ecological significance of building ecological early warning monitoring stations in the estuary and system development direction.

Portions of dynamic traffic volumes consisting of multiple vehicle classes are accurately monitored without vehicle detectors using vehicle-to-infrastructure (V2I) communication systems. This offers the feasibility of online monitoring of the total traffic volumes with multi-vehicle classes without any advanced vehicle detectors. To evaluate this prospect, this article presents a method of monitoring dynamic multi-class vehicular traffic volumes in a road location where road-side equipment (RSE) for V2I communication is in operation. The proposed method aims to estimate dynamic total traffic volume data for multiple vehicle classes using the V2I sensing probe volume (i.e. partial vehicular traffic volumes) collected through the RSE. An experimental study was conducted using real-world V2I sensing probe volume data. The results showed that traffic volumes for vehicle types I and II (i.e. cars and heavy vehicles, respectively) can be effectively monitored with average errors of 6.69% and 10.89%, respectively, when the penetration rates of the in-vehicle V2I device for the two vehicle types average 0.384 and 0.537, respectively. The performance of the method in terms of detection error is comparable to those of widely used vehicle detectors. Therefore, V2I sensing probe data for multi-vehicle classes can complement the functions of vehicle detectors because the penetration rate of in-vehicle V2I devices is currently high.

Background: In research and production, reproducibility is a key factor, to meet high quality and safety standards and maintain productivity. For microbial fermentations, complex substrates and media components are often used. The complex media components can vary in composition, depending on the lot and manufacturing process. These variations can have an immense impact on the results of biological cultivations. The aim of this work was to investigate and characterize the influence of the complex media component yeast extract on cultivations of Azotobacter vinelandii under microaerobic conditions. Under these conditions, the organism produces the biopolymer alginate. The focus of the investigation was on the respiration activity, cell growth and alginate production. Results: Yeast extracts from 6 different manufacturers and 2 different lots from one manufacturer were evaluated. Significant differences on respiratory activity, growth and production were observed. Concentration variations of three different yeast extracts showed that the performance of poorly performing yeast extracts can be improved by simply increasing their concentration. On the other hand, the results with well-performing yeast extracts seem to reach a saturation, when their concentration is increased. Cultivations with poorly performing yeast extract were supplemented with grouped amino acids, single amino acids and micro elements. Beneficial results were obtained with the supplementation of copper sulphate, cysteine or a combination of both. Furthermore, a correlation between the accumulated oxygen transfer and the final viscosity (as a key performance indicator), was established. Conclusion: The choice of yeast extract is crucial for A. vinelandii cultivations, to maintain reproducibility and comparability between cultivations. The proper use of specific yeast extracts allows the cultivation results to be specifically optimised. In addition, supplements can be applied to modify and improve the properties of the alginate. The results only scratch the surface of the underlying mechanisms, as they are not providing explanations on a molecular level. However, the findings show the potential of optimising media containing yeast extract for alginate production with A. vinelandii, as well as the potential of targeted supplementation of the media. [ABSTRACT FROM AUTHOR]

The dielectric loss angle can better reflect the overall insulation level of mining cables, so it is necessary to implement reliable and effective online monitoring of the dielectric loss angle of mining cables. In order to improve the monitoring accuracy of the dielectric loss angle tan δ of mining cables, a low-frequency dielectric loss angle online monitoring method combining signal injection method and double-end synchronous measurement method is proposed in this paper. Firstly, the superiority of the low-frequency signal in improving the detection accuracy of dielectric loss angle is explained, and the feasibility of the low-frequency signal injection method is analyzed. Secondly, the cable leakage is calculated using the double-terminal synchronous measurement method to measure the core current at the first and last ends of the cable, and the phase sum of the voltage at the first and last ends is selected as the reference phase quantity to realize the effective calculation of the dielectric loss angle tan δ of the cable. Then, the simulation model for online monitoring of dielectric loss angle of mining cable is built, and the feasibility of the online monitoring method proposed in this paper is verified by combining the simulation results. Finally, the theoretical and simulation analysis of the monitoring error of dielectric loss angle of mining cable is carried out. [ABSTRACT FROM AUTHOR]

Topological data analysis (TDA) provides a set of data analysis tools for extracting embedded topological structures from complex high-dimensional datasets. In recent years, TDA has been a rapidly growing field which has found success in a wide range of applications, including signal processing, neuroscience and network analysis. In these applications, the online detection of changes is of crucial importance, but this can be highly challenging since such changes often occur in low-dimensional embeddings within high-dimensional data streams. We thus propose a new method, called PERsistence diagram-based ChangE-PoinT detection (PERCEPT), which leverages the learned topological structure from TDA to sequentially detect changes. PERCEPT follows two key steps: it first learns the embedded topology as a point cloud via persistence diagrams, then applies a nonparametric monitoring approach for detecting changes in the resulting point cloud distributions. This yields a nonparametric, topology-aware framework which can efficiently detect online geometric changes. We investigate the effectiveness of PERCEPT over existing methods in a suite of numerical experiments where the data streams have an embedded topological structure. We then demonstrate the usefulness of PERCEPT in two applications on solar flare monitoring and human gesture detection. [ABSTRACT FROM AUTHOR]

Hydrogen is an excellent alternative energy source, particularly for vehicles. Despite the expansion of a considerable number of infrastructures, such as hydrogen refueling stations, there is a lack of efficient inspection methods for monitoring the hydrogen fuel quality. In this study, a hydrogen impurity analyzer (HIA) based on mobile gas chromatography with a thermal conductivity detector is developed and evaluated for the quality assurance of hydrogen fuel. Accordingly, O 2 , N 2 , and Ar which help in monitoring air leaks at hydrogen refueling stations, and CH 4 , which can also be detected by HIA, are selected as target impurities. The HIA reached limits of detection of 2.93, 0.72, 0.84, and 1.54 μmol/mol for O 2 , Ar, N 2 , and CH 4 , respectively. Moreover, the ISO 14687 requirements are satisfied with respective HIA expanded uncertainties of 2.6, 8.7, 8.2, and 9.4% (coverage factor k = 2). The developed system is ISO-compliant and offers enhanced mobility for online inspections. • Hydrogen impurity analyzer design for online monitoring satisfying ISO 14687. • Customized mobile gas chromatograph and thermal conductivity detector. • Customized to 25% size and weight of a commercial gas chromatograph. • ISO 14687 requirement satisfied for O 2 , Ar, N 2 , and CH 4 detection. • Hydrogen impurity enrichment device reduced detection limit of gas chromatograph. [ABSTRACT FROM AUTHOR]

The array configurations have gained a higher prominence and application in the solar PV system for reducing power losses during partial shading. However, additional wires can increase the vulnerability of these configurations to electrical faults affecting the performance and lifespan of the modules. Hence, this paper investigates the reliability of these configurations under various electrical faults in the MATLAB and prototype experiment platforms. Additionally, a powerline communication-based PV monitoring system along with fault detection through optimal sensors placement and a user-friendly web application are developed to monitor the performance, detect the presence of the fault and access the data during normal and faulty operation of the PV array respectively. The investigation is conducted for 3x3 array configurations, compared using power curves, and electrical parameters, and the performance along with detection is studied using the real-time data from the proposed monitoring system under normal and faulty conditions. From the analysis, the series-parallel has a higher average tolerance of 59.48% and 48.38% than honeycomb (54.16% and 47.43%), bridge-linked (52.56% and 43.96%), and total-cross-tied (53.66% and 37.48%). The proposed low-cost PV monitoring system has effectively monitored the system performance and is capable of detecting various types of faults in PV arrays and notifying the system with an alarm for proper diagnosis. [ABSTRACT FROM AUTHOR]

In order to realize an online power supply, this article develops an explicit design of induction power extraction technology combined with wireless power transmission (WPT) technology. Unlike the power supply mode of traditional batteries of online monitoring devices of high-voltage transmission lines, this technology solves the short battery life cycle problems. First, the principle of induction power extraction is analyzed. Based on the equivalent circuit of the mutual inductance model, expressions of induction power extraction without and with core saturation are derived, respectively. According to the current transformer (CT) magnetic coupling diagram, the open-circuit voltage of the secondary side of the CT is deduced. Therefore, the CT material and size could be selected. The CT coupling model is used to equivalent the current transformer to the ideal voltage source. Then, the four basic topological spaces of the magnetic coupling resonant WPT system are analyzed and calculated, and the efficiency of the SS topology WPT system is analyzed. Furthermore, aiming at long-distance power transmission, this article described the building of a three-coil WPT system and the analysis of the corresponding transmission efficiency and output power expression. With the aid of Maxwell, the technology proposed is simulated based on a 110 kV high-voltage transmission line with 1.2 m as the transmission distance of the system. Finally, the influence of a coupling coefficient and load resistance on the transmission characteristics of the multicoil system is obtained. Consequently, the simulation results with a system output power of 14.4 W verify the effectiveness of the technology. [ABSTRACT FROM AUTHOR]

The article presents in detail the construction of a low-cost, portable online PD monitoring system based on the acoustic emission (AE) technique. A highly sensitive piezoelectric transducer was used as the PD detector, whose frequency response characteristics were optimized to the frequency of AE waves generated by discharges in oil–paper insulation. The popular and inexpensive Teensy 3.2 development board featuring a 32-bit MK20DX256 microcontroller with the ARM Cortex-M4 core was used to count the AE pulses. The advantage of the system is its small dimensions and weight, easy and quick installation on the transformer tank, storage of measurement data on a memory card, battery power supply, and immediate readiness for operation without the need to configure. This system may contribute to promoting the idea of short-term (several days or weeks) PD monitoring, especially in developing countries where, with the dynamically growing demand for electricity, the need for inexpensive transformer diagnostics systems is also increasing. Another area of application is medium-power transformers (up to 100 MVA), where temporary PD monitoring using complex measurement systems requiring additional infrastructure (e.g., control cabinet, cable ducts for power supply, and data transmission) and qualified staff is economically unjustified. [ABSTRACT FROM AUTHOR]

External water (such as rainwater, mountain water and groundwater) will decrease the inflow contaminant concentration in urban sewage plants, and pose challenges in improving the wastewater treatment quality and efficiency. Therefore, removing the external water is vital for this target. A sewage plant in Zhuhai, China, was considered as an example. By performing online flow monitoring, water quality testing, on-site survey and data analysis, the rainfall-derived inflow and infiltration of the sewage system were quantitatively analysed through the pollutant balance method. By proposing key emphases of severe problems, the presented findings will aid in sewage system maintenance and pipeline network renovation. [ABSTRACT FROM AUTHOR]

With the development of the technology of the Internet of Things, more and more operational data can be collected from air conditioning systems. Unfortunately, the most of existing air conditioning controllers mainly provide controlling functions more than storing, processing or computing the measured data. This study develops an online fault detection configuration on the equipment side of air conditioning systems to realize these functions. Modbus communication is served to collect real-time operational data. The calculating programs are embedded to identify whether the measured signals exceed their limits or not, and to detect if sensor reading is frozen and other faults in relation to the operational performance are generated or not. The online fault detection configuration is tested on an actual variable-air-volume (VAV) air handling unit (AHU). The results show that the time ratio of fault detection exceeds 95. 00%, which means that the configuration exhibits an acceptable fault detection effect. [ABSTRACT FROM AUTHOR]

Due to the increasing expansion of renewable energy, especially the widespread installation of solar power plants worldwide, to better exploit and increase the efficiency and quality of power generation, we need to closely monitor the performance of important components of the plant. In this study, using an innovative smart monitoring system and electronic sensors, we monitored components such as power in photovoltaic (PV) arrays in real time, including the phenomenon of hot spots as an example of power loss in PV panels. Detection of hot spots is very difficult to deal with in a large power plant. The results also demonstrated smart monitoring that increased detection speed and increased the efficiency rate per supervisory technician by ≤36% compared with the previous efficiency rate, which was 10% per technical staff, and increased the quality of the operation of each solar power plant. In this paper, meteorological data were coordinated with research data to validate the research. Furthermore, to compare the results of using the smart monitoring method with the conventional observation method, a complete diagram of a 5-kW solar system in MATLAB® 2018 was simulated and output diagrams were presented. Finally, to provide a comprehensive validation, our research results were compared with technical data obtained from a local 5-kW solar power plant located in Sari, Iran (36°33ʹ48″N, 53°03ʹ36″E) with an average annual irradiation of 1490 kWh/m2. When the simulation results and research are analysed, it is clear that the smart and real-time monitoring approach brings various benefits to solar power plants. [ABSTRACT FROM AUTHOR]

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Given progress in water-quality analytical technology and the emergence of the Internet of Things (IoT) in recent years, compact and durable automated water-quality monitoring devices have substantial market potential. Due to susceptibility to the influence of interfering substances, which lowers measurement accuracy, existing automated online monitoring devices for turbidity, a key indicator of a natural water body, feature a single light source and are thus insufficient for more complicated water-quality measurement. The newly developed modularized water-quality monitoring device boasts dual light sources (VIS/NIR), capable of measuring the intensity of scattering, transmission, and reference light at the same time. Coupled with a water-quality prediction model, it can attain a good estimate for continuing monitoring of tap water (<2 NTU, error < 0.16 NTU, relative error < 19.6%) and environmental water samples (<400 NTU, error < 3.86 NTU, relative error < 2.3%). This indicates the optical module can both monitor water quality in low turbidity and provide water-treatment information alerts in high turbidity, thereby materializing automated water-quality monitoring. [ABSTRACT FROM AUTHOR]

This paper presents the results of an ongoing research and development effort to develop an online monitoring (OLM) system to support autonomous microreactor operations. A key component of this work is an evaluation of artificial intelligence (AI) and machine learning (ML) techniques to identify, diagnose, and predict problems with sensors and processes of the reactor. As described herein, selected methods of AI/ML were used to identify and diagnose anomalous sensor and system behaviors using data from a thermal-hydraulic flow loop and from operating nuclear power plants. This work serves to further the state of the art in OLM technologies for nuclear reactor applications and will ultimately result in a comprehensive system to enable OLM of critical structures, systems, components, and processes in microreactors. [ABSTRACT FROM AUTHOR]

Coated steel belts (CSBs) are the primary load-bearing components of elevators. As a result, they may experience severe fatigue failure during their long-term service. In this study, a flexible fatigue fixture for CSBs is designed to simulate the CSB fatigue damage process for implementing a tensile fatigue test. The magnetic induction intensity signal on the surface of the CSB in a geomagnetic field environment is recorded using a high-precision weak magnetic sensor. Moreover, the CSB fatigue damage process is monitored online via the acquired magnetic induction intensity value. The fatigue test results indicate the following: the variation in the magnetic induction intensity signal curve can reflect the entire fatigue failure process when the CSB is under stress; the fatigue failure process of the steel wire inside the CSB does not occur smoothly as its progress occurs in stages; and the variation trend in the residual value between the magnetic induction intensity and fitting curves effectively indicates the degree of fatigue damage caused to the CSB. [ABSTRACT FROM AUTHOR]

Background: In industrial microbial biotechnology, fed-batch processes are frequently used to avoid undesirable biological phenomena, such as substrate inhibition or overflow metabolism. For targeted process development, fed-batch options for small scale and high throughput are needed. One commercially available fed-batch fermentation system is the FeedPlate®, a microtiter plate (MTP) with a polymer-based controlled release system. Despite standardisation and easy incorporation into existing MTP handling systems, FeedPlates® cannot be used with online monitoring systems that measure optically through the transparent bottom of the plate. One such system that is broadly used in biotechnological laboratories, is the commercial BioLector. To allow for BioLector measurements, while applying the polymer-based feeding technology, positioning of polymer rings instead of polymer disks at the bottom of the well has been proposed. This strategy has a drawback: measurement requires an adjustment of the software settings of the BioLector device. This adjustment modifies the measuring position relative to the wells, so that the light path is no longer blocked by the polymer ring, but, traverses through the inner hole of the ring. This study aimed at overcoming that obstacle and allowing for measurement of fed-batch cultivations using a commercial BioLector without adjustment of the relative measurement position within each well. Results: Different polymer ring heights, colours and positions in the wells were investigated for their influence on maximum oxygen transfer capacity, mixing time and scattered light measurement. Several configurations of black polymer rings were identified that allow measurement in an unmodified, commercial BioLector, comparable to wells without rings. Fed-batch experiments with black polymer rings with two model organisms, E. coli and H. polymorpha, were conducted. The identified ring configurations allowed for successful cultivations, measuring the oxygen transfer rate and dissolved oxygen tension, pH, scattered light and fluorescence. Using the obtained online data, glucose release rates of 0.36 to 0.44 mg/h could be determined. They are comparable to formerly published data of the polymer matrix. Conclusion: The final ring configurations allow for measurements of microbial fed-batch cultivations using a commercial BioLector without requiring adjustments of the instrumental measurement setup. Different ring configurations achieve similar glucose release rates. Measurements from above and below the plate are possible and comparable to measurements of wells without polymer rings. This technology enables the generation of a comprehensive process understanding and target-oriented process development for industrial fed-batch processes. [ABSTRACT FROM AUTHOR]

Anaerobic ammon ium oxidizing (anammox) bacteria oxidize ammonium and reduce nitrite, producing N2, and could play a major role in energy-optimized wastewater treatment. However, sensitivity to various environmental conditions and slow growth currently hinder their wide application. Here, we attempted to determine online the effect of environmental stresses on anammox bacteria by using an overnight batch activity test with whole cells, in which anammox activity was calculated by quantifying N2 production via headspace-pressure monitoring. A planktonic mixed culture dominated by "Candidatus Kuenenia stuttgartiensis" strain CSTR1 was cultivated in a 30-L semi-continuous stirring tank reactor. In overnight resting-cell anammox activity tests, oxygen caused strong inhibition of anammox activity, which was reversed by sodium sulfite (30 µM). The tested antibiotics sulfamethoxazole, kanamycin, and ciprofloxacin elicited their effect on a dose-dependent manner; however, strain CSTR1 was highly resistant to sulfamethoxazole. Anammox activity was improved by activated carbon and Fe2O3. Protein expression analysis from resting cells after anammox activity stimulation revealed that NapC/NirT family cytochrome c (KsCSTR_12840), hydrazine synthase, hydrazine dehydrogenase, hydroxylamine oxidase, and nitrate:nitrite oxidoreductase were upregulated, while a putative hydroxylamine oxidoreductase HAO (KsCSTR_49490) was downregulated. These findings contribute to the growing knowledge on anammox bacteria physiology, eventually leading to the control of anammox bacteria growth and activity in real-world application. Key Points: • Sulfite additions can reverse oxygen inhibition of the anammox process • Anammox activity was improved by activated carbon and ferric oxide • Sulfamethoxazole marginally affected anammox activity [ABSTRACT FROM AUTHOR]

The compound acetaldehyde has complex synthesis kinetics since it accumulates during the growth phase and is consumed by yeast during the stationary phase, as well as evaporating (low boiling point) throughout the process. One recurrent question about this molecule is: can temperature both increase and decrease the consumption of the molecule by yeast or does it only promote its evaporation? Therefore, the main objective of this study was to describe and analyze the evolution of acetaldehyde and shed light on the effect of temperature, the main parameter that impacts fermentation kinetics and the dynamics of acetaldehyde synthesis. Thanks to new online monitoring approaches, anisothermal temperature management and associated mathematical methods, complete acetaldehyde production balances during fermentation made it possible to dissociate biological consumption from physical evaporation. From a biological point of view, the high fermentation temperatures led to important production of acetaldehyde at the end of the growth phase but also allowed better consumption of the molecule by yeast. Physical evaporation was more important at high temperatures, reinforcing the final decrease in acetaldehyde concentration. Thanks to the use of production balances, it was possible to determine that the decrease in acetaldehyde concentration during the stationary phase was mainly due to yeast consumption, which was explained by the metabolic links found between acetaldehyde and markers of metabolism, such as organic acids. [ABSTRACT FROM AUTHOR]

Online monitoring of outdoor high voltage SF6 circuit breakers (HVCBs) is essential to detecting potential damages. To this end, the study of accurate and non-invasive monitoring methods has been significantly investigated in recent decades. Considering that HVCB vibration patterns carry important information about mechanical and electrical integrity and that vibration analysis requires a low level of invasiveness, this article presents methods of obtaining mechanism and reaction times using interference signals of outdoor high voltage SF6 circuit breakers (HVCBs). Compared to traditional methods of monitoring outdoor SF6 circuit breakers that are based on encoders, the proposed method presented ease of installation, as it only requires the insertion of accelerometers. The method of obtaining the mechanism time is based on the use of interference and auxiliary contact signals, in the time domain, where the accelerometer is installed, in the structure of the HVCB, makes it possible to guarantee the moment of the trip command. To obtain the reaction time of each HVCB pole, the envelope technique was applied with the Hilbert transform module of the hearing signal, filtered in a certain resonance band. The proof of the technique of analyzing the vibration of the signal in time was developed with laboratory tests of an HVCB, instrumented with accelerometers and angular encoders. The results obtained via vibration analysis were compared with those obtained via angular encoders and it was concluded that with the acceleration signals, in time, it is possible to obtain performance parameters of an HVCB from its displacement curve. Finally, the online monitoring of the circuit breaker applied in the field is presented, where the acquisition of trip current signals, the condition of the SF6 gas and extinguishing current signals were added to the instrumentation. [ABSTRACT FROM AUTHOR]

Lubricants have the ability to reduce frictions, prevent wear, convey metal debris particles and increase the efficiency of heat transfer; therefore, they have been widely used in mechanical systems. To assess the safety and reliability of the machine under operational conditions, the development of inductive debris sensors for the online monitoring of debris particles in lubricants has received more attention from researchers. To achieve a high-precision, high-efficiency sensor for accurate prediction on the degree of wear, the equivalent circuit model of the sensor coil has been established, and its equations discovering the relationship between the induced voltage and excitation frequency have been derived. Furthermore, the influence of excitation frequencies and metal debris on the magnetic flux density has been analyzed throughout the simulations to determine the sensor magnetic field. In order to identify a frequency range suitable for detecting both ferrous and non-ferrous materials with a high level of sensitivity, the analytical analysis and experiments have been conducted to investigate the frequency characteristics of the developed inductive debris sensor prototype and its improved inspection capability. Moreover, the developed inductive debris sensor with the noticeable frequency characteristics has been assessed and its theoretical model has been also validated throughout experimental tests. Results have shown that the detection sensitivity of non-ferrous debris by the developed sensor increases with the excitation frequency in the range of 50 kHz to 250 kHz, while more complex results for the detection of ferrous debris have been observed. The detection sensitivity decreases as the excitation frequency increases from 50 kHz to 300 kHz, and then increases with the excitation frequency from 300 kHz to 370 kHz. This leads to the effective selection of the excitation frequency in the process of inspection. In summary, the investigation into the frequency characteristics of the proposed novel inductive debris sensor has enabled its broad applications and also provided a theoretical basis and valuable insights into the development of inductive debris sensors with improved detection sensitivity. [ABSTRACT FROM AUTHOR]

Endotoxin (lipopolysaccharide: LPS), a bacterial toxin, is currently quantified by batch analysis using a reagent made from Limulus amebocyte lysate (LAL). Although the LAL method is sensitive, a long measurement time and gelation have hindered its application to online water quality monitoring. In this paper, we report a novel high-throughput analytical technique that combines flow injection analysis (FIA) and a dipicolylamine-type fluorescent probe, which was previously reported to exhibit strong fluorescence emission in response to LPS. A comparison of normal and reverse FIA systems revealed that the normal FIA offers more rapid detection with throughput of 30 samples per hour, which is the highest among known LAL methods and alternative LPS detection methods that have been recently reported. On the other hand, the reverse FIA requires much less reagent (480 μL per sample). Continuous online monitoring of water quality and analysis of real samples spiked with LPS were realized by this technique.

To evaluate the online presence of wildlife crime and the public’s reaction to these crimes, we collected data on species, locations, animal status, and motives of wildlife crime depicted on nine Pakistani Facebook pages and eight groups from January 2016 to May 2021. We categorized reactions to images depicting birds, mammals, and reptiles and applied generalized linear models to the total number of reactions on posts. In 594 relevant posts, we identified 10,644 animals of 138 species. Common Krait (Bungarus caeruleus) had the highest number of posts, followed by Grey Francolin (Ortygornis pondicerianus) and Black Francolin (Francolinus francolinus). The number of posts has generally increased, particularly after the Covid-19 lockdown in March 2020. Almost 66 % of the posts showed animals being killed, 27 % were captured with no visible signs of torture, and the rest showed visible signs of torture in captivity. The most common reason for wildlife crimes was illegal hunting, followed by fear and illegal trade. Most victims of illegal hunting were birds, while reptiles were predominantly killed for fear. However, illegal trade was affecting all three classes of animals. Killed or tortured animals received more reactions than non-tortured animals, as well as more comments both against and in favor of the crime. Crimes against reptiles received more pro-crime comments than birds and mammals. Our results reflect the importance of social media to monitor wildlife crimes. Urgent actions are necessary by the relevant authorities to improve management and strengthen the response of law enforcement to wildlife crime.

The health care cost of cardiovascular diseases (CVD) in the EU is estimated to be today over 282 billion euros. It is well documented today that exercise training is one of the main strategies for secondary disease prevention and the follow-up integration of these patients. This study aimed to examine patients’ attitudes towards online exercise with mobile monitoring of their vital signs. More specifically, the research objectives were as follows: (a) to examine patients’ attitudes and expectations of online exercise, (b) cluster patients in high- and low-attitude groups and examine their intention to participate in online exercise, and (c) to examine age and gender differences in terms of their intention to exercise online. The final goal of this project was to develop a real application that could be of use to patients and professionals. Data were collected from fifty patients in the city of Thessaloniki, Greece. The results revealed that most patients were positive about exercising online if the programs were perceived as fun and, especially, safe. The use of an online monitoring application with the distant supervision of health professionals could both motivate them and strengthen their feeling of safety.

This review emphasizes the significance of formulating control strategies for biological and advanced oxidation process (AOP)-based wastewater treatment systems. The aim is to guarantee that the effluent quality continuously aligns with environmental regulations while operating costs are minimized. It highlights the significance of understanding the dynamic behaviour of the process in developing effective control schemes. The most common process control strategies in wastewater treatment plants (WWTPs) are explained and listed. It is emphasized that the proper control scheme should be selected based on the process dynamic behaviour and control goal. This study further discusses the challenges associated with the control of wastewater treatment processes, including inadequacies in developed models, the limitations of most control strategies to the simulation stage, the imperative requirement for real-time data, and the financial and technical intricacies associated with implementing advanced controller hardware. It is discussed that the necessity of the availability of real-time data to achieve reliable control can be achieved by implementing proper, accurate hardware sensors in suitable locations of the process or by developing and implementing soft sensors. This study recommends further investigation on available actuators and the criteria for choosing the most appropriate one to achieve robust and reliable control in WWTPs, especially for biological and AOP-based treatment approaches.

Micro direct methanol fuel cells (μDMFCs) are a promising power source for microelectronic devices and systems. As the operating state and performance of a μDMFC is generally determined by both electrochemical polarization and methanol crossover, it is important to monitor the methanol concentration in μDMFCs. Here, we design and fabricate a microwave sensor and integrate it with a μDMFC for the online detection of methanol concentration in a nonintrusive way. The sensing area is set at the bottom of the anode chamber of a μDMFC which exhibits a maximum output power density of 28.8 mW cm−2 at 30 °C. With a square ring structure, the dual-mode microwave sensor shows a sensitivity of 9.5 MHz mol−1 L. Furthermore, the importance of methanol concentration monitoring is demonstrated in the long term. A relatively smooth methanol decline curve was obtained, which indicated a normal and stable operating status of the μDMFC. Derived from real-time recording data, fuel utilization was additionally calculated as 28.5%.

A water quality monitoring buoy installed in the center of the eutrophic shallow lake Ulansuhai was used to explore the dissolved oxygen (DO) balance. A revised DO model for shallow eutrophic lakes was applied to identify trends in the lake's DO content during the non-frozen period and determine the equilibrium relationship of DO in the water body. The coefficient of determination and the Nash efficiency of the model proved the feasibility of the model. The main drivers affecting the DO balance of the lake were photosynthesis, aeration and the lateral movements of oxygen-rich water, which accounted for 49.28, 14.72 and 36%, respectively, whereas respiration and sediment oxygen consumption, on the other hand, accounted for 1.56 and 98.44%, respectively. These findings suggest that photosynthesis and sediment oxygen consumption dominate the DO balance in eutrophic shallow lakes. A trend analysis of the average oxygen production and consumption rates indicated a maximum of 0.22 mg/L·h for photosynthesis and 0.20 mg/L·h for sediment oxygen consumption. A correlation analysis showed that water temperature was involved in changing the DO level of the lake mainly by affecting the oxygen consumption process. HIGHLIGHTS Continuous DO data were obtained by an on-line monitoring instrument with high frequency, and the data were simulated.; A model of DO in a shallow water eutrophication lake is improved and successfully applied to typical lakes in the study area.; The main driving factors of DO were found out and their variation range was determined.;

In view of MOA （metal-oxide arrester） deterioration monitoring， a monitoring method based on an improved hidden Markov model （HMM） is proposed. An improved HMM model used for MOA deterioration monitoring is established by obtaining MOA leakage current data in a substation. According to the MOA leakage current harmonics content of the same bus in the substation， the HMM observation probability matrix is obtained using D-S （Dempster-Shafter） evidence fusion theory and particle swarm optimization. The influence of grid voltage harmonics on the model is studied by MATLAB simulation. The simulation results show that the maximum errors of MOA nonlinear characteristic coefficients a and k are 0.21% and 0.02%， respectively， under the interference of voltage harmonics. It has been proved that the model can counteract the influence of power grid voltage harmonics and improve the online monitoring accuracy of MOA deterioration.

We designed a tunable diode laser absorption spectroscopy (TDLAS) sensor for the online monitoring of CO2 and H2O concentrations. It comprised a small self-design multi-pass cell, home-made laser drive circuits, and a data acquisition circuit. The optical and electrical parts and the gas circuit were integrated into a portable carrying case (height = 134 mm, length = 388 mm, and width = 290 mm). A TDLAS drive module (size: 90 mm × 45 mm) was designed to realize the function of laser current and temperature control with a temperature control accuracy of ±1.4 mK and a current control accuracy of ±0.5 μA, and signal acquisition and demodulation. The weight and power consumption of the TDLAS system were only 5 kg and 10 W, respectively. Distributed feedback lasers (2004 nm and 1392 nm) were employed to target CO2 and H2O absorption lines, respectively. According to Allan analysis, the detection limits of CO2 and H2O were 0.13 ppm and 3.7 ppm at an average time of 18 s and 35 s, respectively. The system response time was approximately 10 s. Sensor performance was verified by measuring atmospheric CO2 and H2O concentrations for 240 h. Experimental results were compared with those obtained using a commercial instrument LI-7500, which uses non-dispersive infrared technology. Measurements of the developed gas analyzer were in good agreement with those of the commercial instrument, and its accuracy was comparable. Therefore, the TDLAS sensor has strong application prospects in atmospheric CO2 and H2O concentration detection and ecological soil flux monitoring. [ABSTRACT FROM AUTHOR]

Background: Non-invasive online fluorescence monitoring in high-throughput microbioreactors is a well-established method to accelerate early-stage bioprocess development. Recently, single-wavelength fluorescence monitoring in microtiter plates was extended to measurements of highly resolved 2D fluorescence spectra, by introducing charge-coupled device (CCD) detectors. Although introductory experiments demonstrated a high potential of the new monitoring technology, an assessment of the capabilities and limits for practical applications is yet to be provided. Results: In this study, three experimental sets introducing secondary substrate limitations of magnesium, potassium, and phosphate to cultivations of a GFP-expressing H. polymorpha strain were conducted. This increased the complexity of the spectral dynamics, which were determined by 2D fluorescence measurements. The metabolic responses upon growth limiting conditions were assessed by monitoring of the oxygen transfer rate and extensive offline sampling. Using only the spectral data, subsequently, partial least-square (PLS) regression models for the key parameters of glycerol, cell dry weight, and pH value were generated. For model calibration, spectral data of only two cultivation conditions were combined with sparse offline sampling data. Applying the models to spectral data of six cultures not used for calibration, resulted in an average relative root-mean-square error (RMSE) of prediction between 6.8 and 6.0%. Thus, while demanding only sparse offline data, the models allowed the estimation of biomass accumulation and glycerol consumption, even in the presence of more or less pronounced secondary substrate limitation. Conclusion: For the secondary substrate limitation experiments of this study, the generation of data-driven models allowed a considerable reduction in sampling efforts while also providing process information for unsampled cultures. Therefore, the practical experiments of this study strongly affirm the previously claimed advantages of 2D fluorescence spectroscopy in microtiter plates. [ABSTRACT FROM AUTHOR]

Online aging monitoring is the basis for high reliability operation of Insulated gate bipolar transistors (IGBTs). Most monitoring methods focus on the package-related aging. Leakage current (Ileak) has been proposed as a potential chip-related aging (CRA) indicator for IGBTs. However, this method has not been implemented online due to the difficulty in accurate online leakage current measurement. An effective online CRA monitoring method is still required for IGBTs. A novel online CRA monitoring method based on Ileak for IGBTs is proposed in this article. First, an online Ileak measurement circuit is proposed. Second, based on this circuit, an aging monitoring strategy is presented. Finally, accelerating aging tests validate the effectiveness of the proposed method. The on-state voltage drop is selected as an aging indicator for comparison. The proposed method has three advantages. The online CRA monitoring is achieved. It can be used in slight aging situation with high sensitivity because Ileak is linear to the CRA levels. The measurement circuit required by this method is simple and low-cost. [ABSTRACT FROM AUTHOR]