Operation Of Module Research Articles

How applicable are the KuMo and FiC as teaching tools for mathematics content?

The module operation still seems essential, and not all students are motivated to learn it. In this case, the teaching materials and the learning model are the benchmark for student success in learning. The Plomp development model is used to build mathematics modules. This module is inspired by teaching materials that can be more diverse and interesting. The aim of developing a mathematics module based on comparative fiqh comic material using the Kumon model is to determine the development process and effectiveness of use based on feasibility test requirements, as well as student responses to the development of a mathematics comic module for comparative learning for junior high school students at YALC Pasuruan. The research results on the development of the mathematics comic module show that the module development process consisting of a preliminary research stage, a prototyping search stage, and an evaluation stage of its application to learning comparative material is feasible and valid for use—student responses showing excellence. However, the Kumon module media based on fiqh comics has yet to maximize students’ understanding of concepts as measured by their mathematical abilities.

IMPROVED ERROR LOGGING WHEN WORKING WITH THE SELENIUM MODULE IN PYTHON

The article discusses the method of logging (saving) errors resulting from the operation of the selenium module, in case of an unexpected or, conversely, an assumed error, save all data about it for future solutions to this error.
 Purpose: development of a method for saving unexpected and expected errors that occur during the operation of the selenium module.
 Method or methodology of work: the article is developing a module capable of saving the error text, where in the code it occurred, its time and the image of the browser page at the time of the error.
 Result: the selenium error planning module has been developed.

Transport modulus of in-pipe diagnostic robot

The paper presents the transport modulus design of an in-pipe diagnostic robot. The transport module is based on two load-bearing platforms with three radially mounted support legs with independent drive wheel engines. The proposed design solves the problem of increasing the mobility of the robot through technical solutions that ensure operation in pipes of complex configurations and various diameters and increase the length of the section inspect-ed in one pass. The algorithm of operation of the transport module is described when it is brought into working po-sition, moves along the pipe, passes between pipes of different diameters, passes bends, inclined sections and adapters.

Superior performance of a membrane bioreactor through innovative in-situ aeration and structural optimization using computational fluid dynamics.

The optimization of membrane bioreactors (MBRs) involves a critical challenge in structural design for mitigation of membrane fouling. To address this issue, a three-dimensional computational fluid dynamics (CFD) model was utilized in this study to simulate the hydrodynamic characteristics of a flat sheet (FS) MBR. The optimization of the membrane module configuration and operating conditions was performed by investigating key parameters that altered the shear stress and liquid velocity. The mixed liquor suspended solids (MLSS) concentration was found to increase the shear stress, leading to a more uniform distribution of shear stress. By optimizing the appropriate bubble diameter to 5mm, the shear stress on the membrane surface was optimized with relatively uniform distribution. Additionally, extending the side baffle length dramatically improved the uniformity of the shear stress distribution on each membrane. A novel in-situ aeration method was also discovered to promote turbulent kinetic energy by 200 times compared with traditional aeration modes, leading to a more uniform bubble streamline. As a result, the novel in-situ aeration method demonstrated superior membrane antifouling potential in the MBR. This work provides a new approach for the structural design and optimization of MBRs. The innovative combination of the CFD model, optimization techniques, and novel in-situ aeration method has provided a substantial contribution to the advancement of membrane separation technology in wastewater treatment.

Temperature profiles of field-aged photovoltaic modules affected by optical degradation

Moisture ingress into PV module in the presence of ultraviolet radiation, high temperature, and other environmental stressors can affect the optical integrity of the PV module. Optical degradation can take the form of delamination, discolouration of encapsulant, metal grids corrosion, and trapped moisture or chemical species. This can influence the photon absorption and current transport properties in the PV module bulk, which can affect the module operating temperature. In the present work, the relationship between optical degradation and temperature sensitivity of 20-year-old multicrystalline silicon field-aged PV modules have been investigated. The selected PV modules were characterized using visual inspection, current-voltage (I–V) characterization, temperature coefficients profiling, current resistivity profiling, infrared (IR) thermal, ultraviolet fluorescence (UV–F), and electroluminescence (EL) imaging. PV modules affected by optical degradation show weak fluorescence and luminescence signal intensities. The average difference in cell temperature (ΔT) between the warmest and coldest cell for the PV modules investigated was found to be around 10 ± 2 °C and the average power degradation rate was approximately 0.8% per year. The underlying factor for the observed degradation is attributed to the degradation in the temperature coefficients of open circuit voltage (βVoc) and maximum power point voltage (βVmpp). The average temperature coefficient of efficiency (βηm) of the modules was found to be around −0.5%/°C. Finally, a temperature dependent resistivity method for extracting temperature coefficients from IR thermal data of PV modules has been proposed.

Common misinterpretations of thermal signatures on polycrystalline PV modules under different operational conditions

Thermal Infrared (TIR) images may be misinterpreted due to the dynamic nature of the operational current–voltage (I-V) and thermal characteristics of photovoltaic (PV) cells and modules. This study investigates and analyses the I-V and thermal characteristics of polycrystalline PV modules to understand the behaviour of abnormal thermal signatures (hot cells) under varying operational points on a module’s I-V curve. A change in operational conditions influences the operational voltage points such that the mismatched cells behave differently under changing load conditions, varying irradiance and partial shading. Mismatched cells can operate in reverse bias and cause abnormal thermal signatures when the module’s operational voltage is less than the maximum power voltage(VMP), 24 V. The mismatch becomes more significant when the operational voltage is 0.2 V, close to short circuit conditions. Cell partial shading of < 10% results in dynamics of the abnormal thermal signatures and can mislead decisions during TIR imaging inspections when bad cells do not show abnormal thermal signatures on TIR images. Carrying out TIR imaging on clean PV modules operating at < VMP will enhance mismatch and the bad cells can show as hot cells, unlike when operating at > VMP. Under low irradiance of < 600Wm−2, mismatched cells can easily emerge on TIR images, however, at irradiance levels > 600Wm−2, only cells having large isolated parts will cause significant mismatch and appear hot on TIR images. This study advances the understanding of the dynamics of operational I-V points and thermal signatures and can improve the operation and TIR imaging inspections of PV modules.

Optimization of module structure considering mechanical and thermal safety of pouch cell lithium-ion batteries using a reliability-based design optimization approach

Design optimization is an important method for improving the performance of lithium-ion batteries. However, the majority of earlier studies on battery optimization have generally concentrated on enhancing the performance of a single battery cell or focusing on particular objectives of the module and pack structures. Therefore, this study mainly focuses on developing a generalized optimization framework to increase the energy density of the module while satisfying the mechanical and thermal safety requirements. To the best of our knowledge, this work is the first to attempt to enhance the module performance while considering both mechanical and thermal safety. Moreover, this study develops a reliability-based design optimization (RBDO) framework for module structures that considers system uncertainties to mitigate the possibility of safety failures and obtain a reliable design. The mechanical behavior of the module shows how swelling, breathing, material types, and properties affect the final module length and stress. The effects of the C-rate and design parameters on the maximum temperature and temperature deviation are also investigated. All designs satisfy the target probability of failure, verifying that the RBDO framework of the module structure has been successfully established. The proposed RBDO framework provides guidance for the design and operation of battery modules.

Non‐contact and anti‐interference diagnosis of SiC MOSFET module bond wire faults for EV wireless charging device

AbstractSiC MOSFET modules are widely used for bidirectional wireless charging of electric vehicles. However, prolonged use can result in bond wire faults, leading to reliability issues. To address this problem, a non‐contact bond wire monitoring method that can be carried out using the charging coil of the wireless charging device is proposed. Here, two monitoring loops are constructed based on the circuit topology, and their impedance magnitudes are measured on the charging coil to avoid the influence of battery voltage on monitoring results. To detect the bond wire condition, the impedance magnitude difference of the two monitoring loops is chosen as an indicator, which is very sensitive to the bond wire lift‐off. However, the monitoring results may be influenced by the aging of resonant capacitors and the offset of the charging coil. In particular, the influence of the coil offset is significant. To mitigate this effect, a prognostic parameter calibration method is proposed. Experimental results confirm the effectiveness of the proposed method, which provides a promising solution for the reliable and safe operation of SiC MOSFET modules in wireless charging devices.

Evaluation of front and backside performances of a large surface organic photovoltaic module under bifacial illumination

Semitransparency is one of the attractive characteristics of thin-film solar modules as it allows electricity generation while providing building illumination. However, enhancing transparency can result in lower energy generation efficiency. An effective way to improve energy production in semitransparent modules is through bifacial illumination. This work aims to evaluate, experimentally, and discuss the optical and electrical properties of a commercial, semitransparent organic photovoltaic (OPV) module under bifacial illumination. With that purpose, current-voltage characteristic curves were obtained under the following conditions: a) front, b) rear illumination and c) simultaneous illumination on both faces. The module was placed inside a V-trough cavity to implement electrical measurements with the module's both faces simultaneously illuminated by natural sunlight. Results show that bifacial illumination is an effective way to enhance energy production in semitransparent OPV devices, and a 46% increase in power generation compared to traditional illumination (frontal illumination) was achieved in the experiments. The backside illumination performance differs by over 40%, compared with the front side, due to electrode shading, optics, and differences in the energy conversion processes taking place in the active layer. The OPV module operation under bifacial illumination is equivalent to a parallel connection between the front and backside illumination performances. Optical modeling shows that the active layer absorbs a large part of the incoming light within the cell spectral response. Nevertheless, in the case of frontal illumination, a significant fraction of solar radiation in the visible region is transmitted and remains available, for instance, for building illumination purposes.

Comparison of heating modules for suspension-type multipoint temperature variability management in smart greenhouses

Managing the temperature inside greenhouses is essential for optimum crop growth and the control of diseases and physiological disorders in plants. In large-sized greenhouses, the automatic operation of small-sized multipoint suspension-type heating modules can facilitate better site-specific temperature management by providing favorable uniformity. The objective of this study was to evaluate efficiency of candidate heating modules before the prototype fabrication of a small-sized heating module for smart greenhouses temperature management. Three different heating modules (i.e., finned tubular (FT), fin element positive temperature coefficient (PTCf), and honeycomb positive temperature coefficient (PTCh)) were tested inside a closed chamber (41 m3) and a small greenhouse (98 m3). A wireless sensor network (WSN) was established to monitor the inside environment, operate heating modules, and detect their operational status. In the closed chamber, the PTCf module exhibited a temperature rise rate 8.59% and 7.36% higher than those of the FT and PTCh modules, respectively, while maintaining a superior average temperature variability range of 1.43 – 5.16 (±0.55 – ±0.85) °C. The elapsed times for the three modules were 12.70%, 8.30%, and 10.85% longer than their calculated times, indicating the effectiveness of the heating modules in regulating the environment. During the tests in the small greenhouse, the PTCf module demonstrated a greater average temperature difference between the inside and outside, followed by the FT and PTCh modules. The respective average temperature variability levels inside the greenhouse were recorded as 5.80 – 10.15 (±1.30 – ±2.68) °C, 4.90 – 8.93 (±1.35 – ±2.36) °C, and 4.86 – 9.38 (±1.25 – ±2.35) °C for the three modules. The performance of the PTCf module was better compared to the other two during the experiments in terms of efficiency and maintaining uniformity. However, large-scale field tests with multiple heating modules are required to verify these experimental findings.

Simulation of the Membrane Process of CO2 Capture from Flue Gas via Commercial Membranes While Accounting for the Presence of Water Vapor.

Carbon capture and storage is one of the potential options for reducing CO2 emissions from coal-fired power plants while preserving their operation. Mathematical modeling was carried out for a one-stage membrane process of carbon dioxide capture from the flue gases of coal-fired power plants using commercial gas separation membranes. Our calculations show that highly CO2-permeable membranes provide similar characteristics with respect to the separation process (e.g., a specific area of membrane and a specific level of electrical energy consumption) despite the significant variation in CO2/N2 and H2O/CO2 selectivity. Regarding the development of processes for the recovery of CO2 from flue gas using membrane technology, ensuring high CO2 permeance of a membrane is more important than ensuring high CO2/N2 selectivity. The presence of water vapor in flue gas provides a higher driving force of CO2 transfer through the membrane due to the dilution of CO2 in the permeate. A cross-flow membrane module operation provides better recovery of CO2 in the presence of water vapor than a counter-current operation.

Book Review Hollow Fiber Membrane Contactors: Module Fabrication, Design and Operation, and Potential Applications

The latest developments and applications of hollow fiber membrane contactors (HFMCs) were discussed in this recent published book. Membrane contactor provides gas–liquid or liquid–liquid contact without dispersion of one phase in another, which gives a higher mass transfer coefficient compared to the conventional contactors. Using a microporous hydrophobic or hydrophilic membrane, one of the fluids is immobilized in the pores where the mass transfer is occurred based on the concentration gradient. HFMC technology has been implemented in various applications including gas separation, fermentation, pharmaceuticals, wastewater treatment, chiral separation, semiconductor manufacturing, carbonation of beverages, metal ion extraction, protein extraction, VOC removal from waste gas, and osmotic distillation.

Practical Entropy Accumulation for Random Number Generators with Image Sensor-Based Quantum Noise Sources.

The efficient generation of high-quality random numbers is essential in the operation of cryptographic modules. The quality of a random number generator is evaluated by the min-entropy of its entropy source. The typical method used to achieve high min-entropy of the output sequence is an entropy accumulation based on a hash function. This is grounded in the famous Leftover Hash Lemma, which guarantees a lower bound on the min-entropy of the output sequence. However, the hash function-based entropy accumulation has slow speed in general. For a practical perspective, we need a new efficient entropy accumulation with the theoretical background for the min-entropy of the output sequence. In this work, we obtain the theoretical bound for the min-entropy of the output random sequence through the very efficient entropy accumulation using only bitwise XOR operations, where the input sequences from the entropy source are independent. Moreover, we examine our theoretical results by applying them to the quantum random number generator that uses dark shot noise arising from image sensor pixels as its entropy source.

Compact Single-Port Harmonic Transponder for Backscattering Communications and Energy Harvesting Applications

This article proposes a novel architecture for the design of a single-port harmonic transponder. The need for a diplexer is eliminated by adding a quarter-wave and a one-eighth-wave transmission line, combined with the two quarter-wave stubs that are usually needed in a conventional harmonic transponder. The proposed architecture provides isolation between the fundamental and the second harmonic signals and sends them to the desired port, while only introducing extremely low insertion loss. Compared with a single-resonator-based diplexer, it has a much wider bandwidth and a much more compact size than the conventional dual-port design. The proposed diplexing structure can also be used in the design of a compact single-port harmonic transponder with dc power supply capability. With such a design, the harmonic transponder can not only generate harmonics for communication purposes, but also provide power for the operation of communication modules, while being small in size and working with a single antenna. A harmonic tag with a simple modulation module based on this architecture is designed to demonstrate its practical value. The proposed design can work at a low input power level and is very suitable for future low-power Internet of Things (IoT) applications.

Effect of coloring covers on the electrical parameters of a photovoltaic module

The efficiency of a photovoltaic module can be affected by different factors, including irradiance and temperature, so the environmental conditions to which it is subjected have a great impact on photovoltaic generation. The present work deals with the analysis of the electrical parameters of a photovoltaic module when it is exposed to the elements and the cells are covered with a layer of plastic material, in this case cellophane, characterized by being thin and having some transparency. The analysis was carried out with pink, red, orange, yellow, lemon green or light green, green, blue and purple cellophane. In addition, a nano-ceramic gray coating to polarize crystals was added to the tests. This with the purpose of observing if a coating is capable of filtering light for the convenience of the module's operation, improving its performance. The results obtained show that the pink coating is the one that has the least impact on the parameters, while the nanoceramic gray film has the greatest impact.

H–H Configuration of Modular EV Powertrain System Based on the Dual Three-Phase BLDC Motor and Battery-Supercapacitor Power Supply System

A modular approach to the construction of electric machines, drive systems, power supply systems is a new direction of modern technology development. Especially, the modular approach is promising for electric vehicles due to such positive aspects as increased efficiency, fault tolerance, overall reliability, safety, enhanced control capabilities, etc. In this work, the modular approach is comprehensively applied to an EV powertrain system, which includes a dual three-phase (DTP) BLDC motor with two machine modules of an asymmetric configuration, two battery modules and a supercapacitor module (SCM). The proposed H–H configuration of modular EV powertrain system includes four voltage source inverters that combine the power modules with the open ends of the windings (OEW) of the module machine armature, and provide control of their operation. Based on the developed mode system of the OEW machine module operation for EV traction and braking, a general control algorithm for the proposed configuration of the modular EV powertrain system has been developed. It combines the control of the operating modes with the functions of maintaining the required SOC level of the SCM and equalizing the SOCs of the two battery modules. The conducted simulation and experimental studies confirmed the workability and effectiveness of the proposed solutions.

Short Wavelength Photons Destroying Si–H Bonds and Its Influence on High‐Efficiency Silicon Solar Cells and Modules

Photons of varying wavelengths exert substantial effects on silicon heterojunction (SHJ) solar cells. Collaborative research previously establishes that light soaking with long‐wavelength photons can activate boron doping in hydrogenated amorphous silicon (a‐Si:H), thereby augmenting cell efficiency (Eff). Herein, this investigation is extended, exploring the effects of short‐wavelength photons on a‐Si:H layers, SHJ solar cells, and modules. The ultraviolet A (UVA) light with the wavelengths peak of 365 nm can disrupt Si–H bonds, resulting in a notable reduction in hydrogen content within both intrinsic and doped a‐Si:H films, and the deterioration of deteriorated interface passivation. Following exposure to 60 kWh m−2 of UVA light, both Eff and module power output decrease significantly, primarily attributable to the degradation of open‐circuit voltage and fill factor. As a feasible solution, the application of a light‐soaking process or the implementation of UV band cutoff module encapsulants can effectively mitigate the loss induced by UV irradiation, thereby ensuring the long‐term operation of SHJ solar cells and modules. Herein, a deeper understanding of UV‐induced performance changes in a‐Si:H film and its degradation mechanism for SHJ solar cells are contributed to in this research and also a viable strategy is provided to counter UV‐induced degradation.

A thermal network model considering thermal coupling effect and TIM degradation in IGBT modules

Thermal interface materials (TIMs), as important materials for heat dissipation of insulated gate bipolar transistor (IGBT) modules, degrade under long-term thermal cycling, resulting in elevated junction temperatures and threatening the safe operation of IGBT modules. In consideration of the thermal coupling effect in IGBT modules, this paper proposes a three-dimensional thermal network model characterizing the TIM degradation. An IGBT module with the TIM is adopted to establish the finite element method (FEM) model, in which the TIM layer is divided into regular areas. The thermal network is established by simulating the heat transfer paths. The thermal impedance in each path is extracted according to the heat flow through its area considering the TIM degradation. Thereby, the impact of thermal coupling and TIM degradation on junction temperature of IGBT modules could be characterized. Furthermore, the proposed thermal network is verified by simulation from calculation accuracy of junction temperature and TIM temperature.

Development of a control strategy for an air supply module for pressurizing fuel cells in airborne applications

In order to obtain high power and efficiency while operating PEM fuel cells in airborne applications, pressurizing the inlet air is necessary. The control strategy for dynamic operation of an air supply module was developed in order to provide cathode inlet air at optimal conditions (mass flow, pressure, humidity and temperature) for different ambient conditions and varying power demand. A surge avoidance strategy without additional surge control valves was successfully implemented. The system was successfully tested statically and dynamically and afterwards connected to a fuel cell system. The air supply module was able to provide cathode pressure, mass flow and humidity dynamically as requested and the developed control strategy was able to avoid unstable operation.

Integration of thermoelectric generators in a biomass boiler: Experimental tests and study of ash deposition effect

Thermoelectric generators (TEGs) are based on Seebeck effect and produce electricity from a heat flow. They require low maintenance and provide quiet operation. However, they have low efficiency and need suitable temperature values. Accordingly, the integration of TEGs in boilers is a promising approach, since these equipment present high temperature differences between hot gases and water and allows the use of waste heat for water heating. There are experiences of the integration of TEGs in biomass boilers, but almost none with unconventional biomass with a high tendency to ash deposition. The integration of TEG modules in a commercial pellet-fired 25 kWth boiler is described and experimental results, working with pine pellets and with an agropellet (70% of vineyard pruning and 30% of barley straw), are presented. Power produced with only 6 modules can reach 60 W. After quantifying the effect of the temperature on both gas and water sides, the study focuses on analyzing the ash deposition on the exchange surfaces and their effect on TEG modules operation (e.g. power reduction of 0.24 W per hour with pine and 0.78 with agropellet). This effect can be minimized by working with high excess of air or by integrating a cleaning system.