Production Of Panels Research Articles

Characteristic of particles created by preparatory operationsof the particleboard production process

Characteristic of particles created by preparatory operations of the particleboard production process.The production of wood-based panels, taking into account material innovations, involves the need to adjust the operation of technological devices to the properties of basic and auxiliary materials. In this study, it was decided to check the particle sizes after sorting raw materials representing 3 groups: forest biomass – pine branches, agricultural biomass - oilseed plant straw, and post-production material. Fractions were taken from the 2.00 mm mesh sieve of a sorter for the core layer of the particleboard and the fractional composition was determined by sieve analysis. The average linear particle dimensions and bulk density of each lignocellulosic raw material were also determined. Due to the varying proportions, it is necessary to adapt the parameters of the technological operations to the specifics of the raw material being processed or to introduce guidelines for the selection of particle sizes guided by their actual average size. Studies have shown differences between the individual materials. This is particularly important, as proper preparation of the raw material translates into the quality of the boards produced from them and the efficiency of the entire process.

Fault-related feature discrimination network for cell partitioning and defect classification in real-time solar panel manufacturing

During the production of energy using photovoltaic (PV) panels, solar cells may be affected by different environmental aspects, which cause many defects in the solar cells. Such defects should be identified and categorized to improve energy productivity. Most recent studies developed many deep learning models to categorize solar cell defects, whereas tiny defects were not categorized due to the blurry and overlapping edges. Hence, this paper develops an effective deep-learning model of cell partitioning and defect classification to satisfy the criteria for solar panel manufacturing monitoring. At first, the low-resolution solar cell images are enriched into super-resolved images using the improved super-resolved adversarial network. Then, those images are passed to the novel deep feature discrimination network, which extracts fault-related characteristics from the solar cell images. Those characteristics are further fed to the softmax classifier to categorize the defected or non-defected solar cell images. Moreover, a new mixture of error functions is used for fine-tuning and rapid convergence. Further, a detection bias and compensation in missed faults that limit the model accuracy are found to be unaffected by the categorization of defected/non-defected panels in a real-time manufacturing unit. Finally, assigning certain forecasting standards for various faults categories, the overall test analysis using solar cell images on 5 days exhibits that the presented model attains a maximum accuracy of 99.91% compared to the classical deep learning models. So, this model has a high probability to be used in a real manufacturing unit.

Reshoring silicon photovoltaics manufacturing contributes to decarbonization and climate change mitigation

The globalized supply chain for crystalline silicon (c-Si) photovoltaic (PV) panels is increasingly fragile, as the now-mundane freight crisis and other geopolitical risks threaten to postpone major PV projects. Here, we study and report the results of climate change implications of reshoring solar panel manufacturing as a robust and resilient strategy to reduce reliance on foreign PV panel supplies. We project that if the U.S. could fully bring c-Si PV panel manufacturing back home by 2035, the estimated greenhouse gas emissions and energy consumption would be 30% and 13% lower, respectively, than having relied on global imports in 2020, as solar power emerges as a major renewable energy source. If the reshored manufacturing target is achieved by 2050, the climate change and energy impacts would be further reduced by 33% and 17%, compared to the 2020 level. The reshored manufacturing demonstrates significant progress in domestic competitiveness and toward decarbonization goals, and the positive reductions in climate change impacts align with the climate target.

A multi-stage stochastic programming model for the unit commitment of conventional and virtual power plants bidding in the day-ahead and ancillary services markets

As more uncontrollable renewable energy sources are present in the power generation portfolio, the need of more detailed and reliable tools for the optimal operation of energy systems has increased in the last years. This work presents a multi-stage stochastic Mixed Integer Linear Program with binary recourse for optimizing the day-ahead unit commitment of power plants and virtual power plants operating in the day-ahead and ancillary services markets. Scenarios reproduce the uncertainty of the ancillary services market requests, and production of photovoltaic panels. A novel decomposition algorithm is proposed to tackle the challenging multistage stochastic program. The methodology is tested on three types of large power plants: a natural gas-fired combined cycle, a combined heat and power combined cycle with thermal storage, and a virtual power plant integrating a combined cycle with battery and photovoltaic fields. Compared to the typical deterministic unit commitment approach, the proposed stochastic optimization approach allows to increase the revenues of the conventional power plant up to 13.58% and, for the combined heat and power and virtual power plant case, it allows finding a feasible and efficient operational scheduling.

Genotyping for Scianna blood group system polymorphism in Pakistan.

Objective: To establish the occurrence of Scianna blood group alleles via genotyping in Pakistani blood donors. Study Design: Cross-sectional Analytical study. Setting: Department of Hematology, Army Medical College (AMC) in association with the Armed Forces Institute of Transfusion (AFIT) Rawalpindi. Period: January 2019 and January 2020. Material & Methods: In this study 300 blood donors were incorporated after taking informed consent; DNA was extracted from their EDTA anticoagulated blood samples and tested for SC*01 and SC*02 alleles by Sequence-Specific Primer Polymerase Chain Reaction (PCR-SSP), which was ensued by gel electrophoresis. The allele frequencies were established and Hardy Weinberg equilibrium was determined. Chi-square test was applied to compare the observed and expected genotype frequencies as well as for comparison with published allele frequencies of other populations. We used SPSS version 22 for the analysis of study data. Results: All donors were homozygous for SC*01, demonstrating allele frequency for SC*01 nearly 1.00. Genotype frequencies were congruent with the Hardy Weinberg equilibrium. The difference between the allele frequencies of SC*01 and SC*02 alleles of population of Pakistan was not statistically significant when compared to those of other populations. Conclusion: This maiden research illustrates Scianna blood group distribution in Pakistani community by PCR-SSP. This method is cheap and proficient and can be applied in developing nations. The findings of this study can aid in the production of local red cell panels, detection of uncommon blood types, and setting up of a domestic rare blood donor platform.

Optimizing the production technology of eco-friendly foam polyurethane panels on the continuous line

With the preeminent features of polyurethane (PU) panels such as sound insulation, heat insulation, fireproof, high load capacity, lightweight, high aesthetics, especially using simple and easy assembly construction and move, so new PU panel is now the first choice for construction projects. In this work, the authors study the new generation physical foaming agent cyclopentane that is environmentally friendly and completely does not destroy the ozone layer. Study investigating and evaluating the effect of content of physical foam cyclopentane on free expansion density, reaction time of rigid polyurethane foam (R-PUF), and reaction time values ​​(cream time, gel time, tack-free time, and rise time). The morphology and size of the closed-cell of the R-PUF samples with cyclopentane concentrations increasing from 0% to 20% are observed by the optical microscope image and the closed-cell size distribution chart is determined by IT3 software. In addition, the physical and mechanical properties of dimensional stability and compressive strength were analyzed to evaluate the quality of the expanded R-PUF insulation in the mold using a cyclopentane physical foaming agent. Experimental procedures according to Taguchi's analysis on the continuous production line are aimed at giving optimal parameters for the industrial PU panel manufacturing process. The research results provide an excellent reference value for manufacturers to further improve the performance and quality of PU panels.

Influence of epoxy functional silane on the crosslinking process of eucalyptus wood panels using formaldehyde-free acrylate adhesives

ABSTRACT The effect of different amounts of epoxy functional silane (EFS) as a crosslinking agent in the water-based acrylate adhesives was evaluated for the production of eucalyptus wood panels at different curing temperatures (120°C and 140°C). The thermal stability and dynamic analyses (loss and storage moduli) of the acrylate adhesives with EFS were evaluated. The addition of EFS in the acrylate adhesive increased the thermal degradation, storage, and loss moduli. The thermal degradation, bending test, specific mass, and morphology were evaluated in the wood panels. Significant increases in the storage modulus and bending strength of the wood panels with EFS and acrylate adhesive at 140°C were found. These results demonstrate a potential application of EFS in the production of wood panels aiming towards the manufacture of thicker composites.

Crack Detection in Photovoltaic Panel Electroluminescence Image Using Matched Filter for Performance Loss Estimation

The long-term use of renewable energy investments which have gained importance in recent years, can be realized by tracking errors and malfunctions. It is very important to determine the cracks, microcracks and flaws that occur especially during the production and use of solar energy panels. Errors in the panels can seriously affect the energy production performance of the installed system. According to the panel arrangement in the power plant, flaws in any panel not only affect the energy production of a single panel, but also reduce the production of the entire series to which it is connected. Cracks and faults in solar panels cannot be seen with the naked eye, but can be determined by electroluminescence images. However, detecting these errors requires special expertise and a long examination time. In this study, fractures, microcracks and connection errors are detected automatically from electroluminescence images taken from photovoltaic panels. Before analyzing the images taken with the electroluminescence device, some preprocessing is required. Since the images taken from the installed power plants are not standard in terms of layout, background removal, size and perspective correction are required. In the study, the panels are not examined as a whole, but cell-based examination is carried out. For this reason, the panels are divided into cells. By applying the Matched filter to the dividing cell images, the fractures and cracks are highlighted and the features are extracted. The obtained features are evaluated statistically and the cell status is determined. An accuracy of 98.6% is achieved in determining cell damage status. The losses in the power generation performance of the panel are calculated according to the status of all cells on the panel. The calculated values are compared with the measured I-V values. As a result, efficiency loss was calculated with an accuracy rate of 96.2%.

Surface defect detection method for electronic panels based on double branching and decoupling head structure.

During the production of electronic panels, surface defects will inevitably appear. How to quickly and accurately detect these defects is very important to improve product quality. However, some problems such as high cost and low accuracy are still prominent when existing manual detection and traditional techniques are used to solve such problems. Therefore, more and more computer vision techniques are proposed to solve such problems, but the current application of deep learning-based object detection networks for surface defect detection of electronic panels is in a gap. The analysis found that there are two main reasons for this phenomenon. On the one hand, the surface defects of electronic panels have their unique characteristics such as multi-scale and irregular shape, and the current object detection networks cannot effectively solve these problems. On the other hand, the regression and classification tasks coupled in the current computational mechanism of each network are commonly found to cause the problem of conflict between them, which makes it more difficult to adapt these network models to the detection tasks in this scenario. Based on this, we design a supervised object detection network for electronic panel surface defect detection scenario for the first time. The computational mechanism of this network includes a prediction box generation strategy based on the double branch structure and a detection head design strategy that decouples the regression task from the classification task. In addition, we validated the designed network and the proposed method on our own collected dataset of surface defects in electronic panels. The final results of the comparative and ablation experiments show that our proposed method achieves an average accuracy of 78.897% for 64 surface defect categories, proving that its application to electronic panel surface defect detection scenarios can achieve better results.

ВИЗНАЧЕННЯ МАКСИМАЛЬНОЇ ГЛИБИНИ УТЯЖКИ СУПЕРТОНКИХ НЕСУЧИХ ОБШИВОК СЕНДВІЧЕВОЇ ПАНЕЛІ СОНЯЧНОЇ БАТАРЕЇ КОСМІЧНОГО ЛІТАЛЬНОГО АПАРАТУ

Continuous dimple of super-thin skins are purely specific defects that are found in the process of sandwich panels manufacturing of spacecraft solar batteries. These types of defects, both in terms of the nature of their appearance and in the aspect of reduction (elimination), are currently receiving close attention. An analysis of this type of defect, which occurs in the process of assembling a sandwich structure by gluing super-thin load-bearing skins and cellular aggregate, has been carried out. A mathematical model was developed to estimate these dimples, which takes into account the thermal expansion of the cladding and cellular aggregate at the temperature of the panel gluing, followed by icing and fixation of the glue in a heated state, and then cooling the glued panel to normal temperature. On the basis of this model, analytical dependences for determining the maximum depth of dimple were obtained. It was shown that continuous dimples have a relatively small value and are an inevitable consequence of the optimal design implementation with the exception of the only parameter - the temperature difference during cooling from the panel gluing temperature to normal. Therefore, the use of glues that polymerize at lower temperatures (as well as binders for the manufacture of panel skins) can reduce the dimple size. The research results allow solving a number of new tasks of the technology of assembling a structures made of polymer composite materials for aerospace engineering and can be used in the production of other precision products for conversion purposes.

Demanding Innovation: The Impact of Consumer Subsidies on Solar Panel Production Costs

Private sector innovation is critical to mitigating and adapting to climate change. This paper studies innovation in solar energy technology, a key source of clean energy that has experienced rapid price declines over the past decade. To understand the causes and effects of innovation, I estimate a dynamic structural model of competition among solar panel manufacturers. The model captures important features of the industry, including the role of government subsidies for solar adoption, and I employ a unique measure of technological progress that is observable and verifiable. The results produce two main insights. First, ignoring innovation by firms can generate biased estimates of the effects of government policy. Second, decentralized government intervention in a global market generates spillovers; a subsidy in one country causes international firms to innovate more, leading to lower prices and increased adoption elsewhere. This spillover underscores the need for international coordination by governments and the private sector to address climate change. This paper was accepted by Erica Plambeck, Special Section of Management Science on Business and Climate Change. Funding: The author acknowledges support from the U.S. Environmental Protection Agency [Science to Achieve Results (STAR) Fellowship Assistance Agreement FP-91769401-0] and Harvard [Joseph Crump Fellowship]. Supplemental Material: The data files and online appendix are available at https://doi.org/10.1287/mnsc.2022.4662 .

The ‘wicked trinity’ of late capitalism: Governing in an era of stagnation, surplus humanity, and environmental breakdown

Scholars within the fields of political ecology, environmental political theory, and international political economy tend to evaluate the prospects of state-led environmental transitions in general terms – enquiring as to the capitalist state’s inherent properties and their environmental implications. Less attention has been paid to how the state’s green capacities are conditioned by contemporary evolutions in the form and pace of capital accumulation. Capitalism’s directional pattern of historical development poses unique challenges for green state projects. Its drive to raise labour productivity metabolises nature on a growing scale, while generating conditions of overproduction and rendering a progressively larger portion of the population superfluous to the production process.Thus, the question is not simply whether the state can rise to the challenge of climate change, but rather how states are scrambling to govern the intersecting crises of climate catastrophe, economic stagnation, and surplus humanity. This ‘wicked trinity’ compounds the tensions at the heart of the capitalist state, resulting in an increasing inability to perform its role while sustaining its liberal form. This governance trilemma is illustrated by the case of the solar photovoltaic boom, where the spectacular increase in the productivity and scale of solar panel manufacturing have generated oversupply and falling profitability. States have reacted by indefinitely providing subsidies, financing automation technologies thatexacerbate labour superfluity, and relocating solar panel manufacturing to places with authoritarian labour regimes. The case of photovoltaics is a microcosm of the general predicament faced by states as they struggle to govern capitalism’s secular developmental tendencies.

Pembuatan, Pelatihan Perawatan, dan Perbaikan Panel Surya Cell di Proklim Karangmojo Weru Sukoharjo

Development of climate change within the community to increase public awareness about climate change which is increasingly real. The government, through the pro-climate competition, hopes that there will be more understanding and awareness to save the environment. In the proklim competition, it is necessary to have environmentally friendly technology, one of which is a solar cell. Polytechnic Indonusa Surakarta through the MBKM program. Students conduct training, maintenance, and repair of solar cell panels at Proklim Karangmojo Weru Sukoharjo. This is done so that the Karangmojo Proklim won the championship at the national level proklim competition while at the same time increasing public awareness of climate change and also increasing public knowledge about solar cell technology. The method used is a survey, planning, manufacturing, maintenance, and repair of solar panels. The results obtained are solar panels installed properly and running according to plan.

Resistance of Untreated and Torrefied Medium-Density Fiberboard (MDF) Residues to Xylophage Fungi

The manufacture of wood panels generates a large amount of waste. This material can be an option for renewable energy generation. However, long-term storage, exposure to moisture and contact of these panels with the soil facilitate colonization by xylophagous organisms. Torrefaction, a heat treatment between 200 and 300 °C in an oxygen-free atmosphere, is a process that decreases hygroscopicity while increasing carbon content, energy efficiency and resistance to fungal attack. This work aimed to evaluate the resistance of MDF panel residues. The MDF panels were produced using eucalyptus wood and bonded with thermosetting synthetic resin, under high temperature and pressure, torrefied at 300 °C for 20, 30 and 40 min and exposed to the xylophagous fungi of the white rot, Irpex lacteus (Fr.) Fr. (1828) and Trametes versicolor, and that of the brown rot, Postia placenta. After the 12-week evaluation period under fungal exposure, the mass loss of the samples attacked by T. versicolor and P. placenta was similar between treatments, except the MDF untreated, which had greater mass losses from the fungus Irpex lacteus. The torrefaction process increased the material resistance to deterioration by fungi, with an inverse correlation between the torrefaction period and the mass losses by fungal attack of the MDF panel residues.

A Design and Validation of 400 W PV Emulator Using Simple Equivalent Circuit for PV Power System Test

In this paper, we propose a photovoltaic emulator (PVE) composed of a series of connected power diodes with a single constant current source, rather than a power converter-based PVE. Accordingly, this enables readily verifying the operation because a the simple hardware structure and lack of a complex control algorithm. The proposed PVE can be intuitively implemented using the proposed selection criteria for the power diode and equivalent resistances. Since there is no feedback control based on complex analog/digital controls and sensors, the control response can be very fast. In addition, the proposed PVE can be easily integrated with a PV power system such as a power optimizer, to allow testing in a simple and flexible manner. Spice simulation was performed based on the electrical characteristics provided by the solar panel manufacturer, and this was utilized to validate the applied emulator circuit model, the Norton Equivalent Circuit. During the design process, the simulation helped to manufacture the PVE within error ranges satisfying the desired I–V and P–V curves, as well as the maximum power point (MPP). Partial shading could be easily implemented through use of the multiple series connection of individual PVEs, demonstrating local MPP and global MPP. A 400 W class PVE was built through appropriate power diode selection, with a thermal design to increase the output power. Moreover, its performance and feasibility were verified through intensive experiments. The measured efficiency, transient response time, and maximum transient error of the partial shading tests were 91%, 22 μs, and 5.8%, respectively.

Selection of a Photovoltaic Panel Cooling Technique Using Multi-Criteria Decision Analysis

Photovoltaic panel performance in terms of its efficiency and durability is severely affected by operating temperature when the temperature is much higher than the nominal operating cell temperature in hot climates. Different cooling methods have been reported over several decades, but photovoltaic panel manufacturers or users are yet to adopt a popular method of panel cooling. This is the main concern of the present work. Potential cooling solutions differ in terms of their criteria for performance evaluation, which are efficiency enhancement, costs, reliability, environmental aspects and ergonomics. Hence, there is a need to identify the optimum cooling method. Eight different cooling methods were identified, and the analysis was made with the multi-criteria analysis tool on the different possible attributes. Two different climate zones with different weight schemes are considered for the evaluation process, and the best to the worst cooling solutions have been identified. Five different scenarios depending on the importance given to each evaluation criterion are analyzed. The best cooling method to the worst cooling method has been arranged under each scenario. When the efficiency of operation was given maximum weight, aluminum fin cooling proved to be the best panel cooling method. When the emission reduction criterion was given maximum weight, thermosiphon cooling was the best cooling option. A comparison of the results indicates that thermosiphon works out to be the best option. The second-best method was found to be forced convection cooling when equal weights were applied and thermosiphon cooling when a 40% weight on efficiency enhancement criteria was applied, which is a more practical weight distribution. Phase change cooling and forced convection cooling had the poorest performance among the different cooling methods for all the weighing scenarios.

Optimization of Particle Size and Ramie Fiber Ratio on Hybrid Bio Panel Production from Oil Palm Trunk as Thermal Insulation Materials

Optimization of Particle Size and Ramie Fiber Ratio on Hybrid Bio Panel Production from Oil Palm Trunk as Thermal Insulation Materials

A dialdehyde starch-based adhesive for medium-density fiberboards

Bio-based adhesives have gained considerable attention in the last years as more sustainable and healthier alternatives to the formaldehyde-based adhesives used today in wood-based panel manufacturing. In this study, dialdehyde starch (DAS) with various aldehyde contents was prepared by using sodium metaperiodate as an oxidizing agent. Characterizations were performed by employing Fourier-transform infrared spectroscopy, nuclear magnetic resonance, and thermal stability analysis. Different adhesive compositions were used for making medium-density fiberboard (MDF) panels. They were based on DAS (12 wt% based on fiber), emulsifiable diphenylmethane diisocyanate (eMDI, 2-4 wt% based on DAS), and microfibrillated cellulose (MFC, 0.5-1.0 wt% based on DAS). Fibers and the adhesive components were mixed with a combination of dry mixing and wet spraying. The physical and mechanical properties of MDF panels bonded with different DAS-based adhesives were compared with those of melamine urea-formaldehyde (MUF) adhesive and sole eMDI. The results showed that the MDF panels made with DAS-MFC-eMDI of 99.52% bio-based content showed comparable properties to standard panels with a commercial MUF adhesive. It was implied that DAS in the presence of small amount of eMDI can create strong bonds with wood fibers, while an additional positive effect on bonding was due to the contact surface enlargement of MFC.

Adhesives free bark panels: An alternative application for a waste material.

The proportion of bark in tree trunks is in the range of ~ 10-20%. This large amount of material is currently mainly considered as a by- or even waste-product by the timber processing industry. Recently, efforts towards the use of bark have been made, e.g. as a raw material to harvest different chemical compounds or as an additive for wood particle boards. Our motivation for this work was to keep the bark in an almost natural state and explore alternative processes and applications for use. The traditional method of de-barking tree trunks by peeling was used to harvest large bark pieces. Two pieces of peeled bark were placed crosswise, with the rhytidom side (outer bark) facing each other. After different conditioning steps, bark pieces were hot pressed to panels without adding adhesives. These experiments on bark samples of different Central European tree species suggest that production of panels with species dependent properties is possible and feasible. This is a step towards producing sustainable panels by using a natural waste material, while retaining its beneficial structure and its natural chemical composition.

Cross-laminated strand veneer lumber mass timber panels from thermally modified strands

Thin-strand composite panels and subsequent mass timber beams were produced using thermally modified wood strands in a pressurized system. The effects of thermal modification (TM) temperature and dwell time on the mechanical, moisture, and decay performance of panels were studied. TM reduced moisture sorption and increased decay resistance. The thin-strand composites were evaluated in flexure and benchmarked against commercially available structural products. Moreover, the mass timber beams’ out-of-plane bending was accurately predicted with traditionally used laminated beam theory. The study shows that TM, under controlled conditions, enables the production of high-performing wood-strand panels with improved dimensional stability and decay resistance.