bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimization of Management Processes in Assessing the Quality of Stored Grain Using Vision Techniques and Artificial Neural Networks
Authors: Szwedziak Katarzyna , Grzywacz Żaneta , Polańczyk Ewa , Bębenek Piotr , Olejnik Marian
Published: August 2020

The paper presents the method of using vision techniques and artificial neural networks to assess the degree of contamination of cereal during grain reception. The aim of the work is to optimize the management of the contaminant evaluation process of grain mass in warehouse and during purchase using vision techniques based on computer image analysis in order to expedite laboratory work. The obtained photographs of wheat seed samples were analyzed using the “Agropol V06” computer application and neural analysis of the obtained empirical results was performed. The application of computer image analysis reduced the time necessary for the quality assessment of the examined material compared to traditional methods. The generated models were characterized by good parameters and high quality, obtaining a high R2 coefficient at the level of 0.999. As part of the investment project, savings resulting from the time of goods receipt and further production process were made. Profitability was estimated at 191.43% per day. The analysis was made without taking into account other costs related to the business activity. The straight payback period is 3 years.
State-Constrained Sub-Optimal Tracking Controller for Continuous-Time Linear Time-Invariant (CT-LTI) Systems and Its Application for DC Motor Servo Systems
Authors: Kim Jihwan , Jon Ung , Lee Hyeongcheol
Published: August 2020

In this paper, we propose an analytic solution of state-constrained optimal tracking control problems for continuous-time linear time-invariant (CT-LTI) systems that are based on model-based prediction, the quadratic penalty function, and the variational approach. Model-based prediction is a concept taken from model-predictive control (MPC) and this is essential to change the direction of calculation for the solution from backward to forward. The quadratic penalty function plays an important role in deriving the analytic solution since it can transform the problem into a form that does not have inequality constraints. For computational convenience, we also propose a sub-optimal controller derived from the steady-state approximation of the analytic solution and show that the proposed controller satisfies the Lyapunov stability. The main advantage of the proposed controller is that it can be implemented in real time with a lower computational load compared to the implicit MPC. Finally, the simulation results for a DC motor servo system are shown and compared with the results of the direct multi-shooting method and the implicit MPC to verify the effectiveness of the proposed controller.
Investigation of Aerosol Climatology and Long-Range Transport of Aerosols over Pokhara, Nepal
Authors: Regmi Jeevan , Poudyal Khem N , Pokhrel Amod , Gyawali Madhu , Tripathee Lekhendra , Panday Arnico , Barinelli Anthony , Aryal Rudra
Published: August 2020

This study presents the spectral monthly and seasonal variation of aerosol optical depth (τAOD), single scattering albedo (SSA), and aerosol absorption optical depth (AAOD) between 2010 and 2018 obtained from the Aerosol Robotic Network (AERONET) over Pokhara, Nepal. The analysis of these column-integrated aerosol optical data suggests significant monthly and seasonal variability of aerosol physical and optical properties. The pre-monsoon season (March to May) has the highest observed τAOD(0.75 ± 0.15), followed by winter (December to February, 0.47 ± 0.12), post-monsoon (October and November, 0.39 ± 0.08), and monsoon seasons (June to September, 0.27 ± 0.13), indicating seasonal aerosol loading over Pokhara. The variability of Ångström parameters, α, and β, were computed from the linear fit line in the logarithmic scale of spectral τAOD, and used to analyze the aerosol physical characteristics such as particle size and aerosol loading. The curvature of spectral τAOD, α’, computed from the second-order polynomial fit, reveals the domination by fine mode aerosol particles in the post-monsoon and winter seasons, with coarse mode dominating in monsoon, and both modes contributing in the pre-monsoon. Analysis of air mass back trajectories and observation of fire spots along with aerosol optical data and aerosol size spectra suggest the presence of mixed types of transboundary aerosols, such as biomass, urban-industrial, and dust aerosols in the atmospheric column over Pokhara.
A Chemical Transport Model Emulator for the Interactive Evaluation of Mercury Emission Reduction Scenarios
Authors: De Simone Francesco , D’Amore Francesco , Marasco Francesco , Carbone Francesco , Bencardino Mariantonia , Hedgecock Ian M. , Cinnirella Sergio , Sprovieri Francesca , Pirrone Nicola
Published: August 2020

Implementation of the Minamata Convention on Mercury requires all parties to “control, and where feasible, reduce” mercury (Hg) emissions from a convention-specified set of sources. However, the convention does not specify the extent of the measures to be adopted, which may only be analysed by decision-makers using modelled scenarios. Currently, the numerical models available to study the Hg atmospheric cycle require significant expertise and high-end hardware, with results which are generally available on a time frame of days to weeks. In this work we present HERMES, a statistical emulator built on the output of a global Chemical Transport Model (CTM) for Hg (ECHMERIT), to simulate changes in anthropogenic Hg (Hganthr) deposition fluxes in a source-receptor framework, due to perturbations to Hganthr emissions and the associated statistical significance of the changes. The HERMES emulator enables stakeholders to evaluate the implementation of different Hganthr emission scenarios in an interactive and real-time manner, simulating the application of the different Best Available Technologies. HERMES provides the scientific soundness of a full CTM numerical framework in an interactive and user-friendly spreadsheet, without the necessity for specific training or formation and is a first step towards a more comprehensive, and integrated, decision support system to aid decision-makers in the implementation of the Minamata Convention.
Space-Borne Monitoring of NOx Emissions from Cement Kilns in South Korea
Authors: Kim Hyun Cheol , Bae Changhan , Bae Minah , Kim Okgil , Kim Byeong-Uk , Yoo Chul , Park Jinsoo , Choi Jinsoo , Lee Jae-bum , Lefer Barry , Stein Ariel , Kim Soontae
Published: August 2020

Nitrogen oxide (NOx) emissions from the South Korean cement industry are investigated with remote-sensing measurements, surface observations, and in situ aircraft measurements. In the Yeongwol, Danyang, and Jecheon regions of central South Korea, six closely located cement factories produce 31 million tons of cement annually. Their impact on the regional environment has been a public-policy issue, but their pollutants have not been continuously monitored nor have emissions inventories been fully verified. Using a newly developed downscaling technique, remote-sensing analyses show that Ozone Monitoring Instrument (OMI) NO2 column densities over the cement kilns have more than twice the modeled concentrations, indicating that the kilns are one of the most dominant NOx emission point sources in South Korea. Observed NOx emissions are stronger in the spring, suggesting that these sources play an important role in the formation of surface ozone and secondary particulate matter. These emissions also slightly increased in recent years, even while most major South Korean cities posted a declining trend in NOx emissions. Photochemical models (during May to July 2015) demonstrate that emissions from the South Korean cement industry have significant environmental impacts, both on surface ozone (up to approximately 4 ppb) and PM2.5 (up to approximately 2 µg/m3).
Ambient Air Quality as a Condition of Effective Healthcare Therapy on the Example of Selected Polish Health Resorts
Authors: Kobus Dominik , Merenda Beata , Sówka Izabela , Chlebowska-Styś Anna , Wroniszewska Alicja
Published: August 2020

This article discusses the importance of air quality for the organization and functioning of health resorts. Ten different types of resorts located in various regions of Poland were compared in terms PM10 concentration. Additionally, comparative analysis of the high-PM10 episodes was performed in three urban agglomerations located near the analyzed health resorts. The article also discusses formal, legal, and economic instruments that are the basis for legislative actions as tools for managing the air quality in the selected resorts. The analysis of the average annual concentrations in 2015–2019 did not show any exceedances of the PM10 limit value for any of the health resorts studied. High PM10 concentration values in 2018 were recorded for the number of days in exceedance of the limit value, especially in the health resorts of Uniejów, Ciechocinek, and Szczawno-Zdrój. Health resorts located in the south of Poland were identified as the most at risk in terms of the occurrence of limit value exceedances, information, and alert thresholds. It was concluded that the implementation of the so called “anti-smog” resolutions, including the development of financial support for changing the heating system to eliminate coal boilers and furnaces, is absolutely necessary for air quality improvement.
Photoionization of Astrophysically Relevant Atomic Ions at PIPE
Authors: Schippers Stefan , Müller Alfred
Published: August 2020

We review recent work on the photoionization of atomic ions of astrophysical interest that has been carried out at the photon-ion merged-beams setup PIPE, a permanently installed end station at the XUV beamline P04 of the PETRA III synchrotron radiation source operated by DESY in Hamburg, Germany. Our results on single and multiple L-shell photoionization of Fe+, Fe2+, and Fe3+ ions, and on single and multiple K-shell photoionization of C−, C+, C4+, Ne+, and Si2+ ions are discussed in astrophysical contexts. Moreover, these experimental results bear witness of the fact that the implementation of the photon-ion merged-beams method at one of the world’s brightest synchrotron light sources has led to a breakthrough for the experimental study of atomic inner-shell photoionization processes with ions.
An Accelerated Extragradient Method for Solving Pseudomonotone Equilibrium Problems with Applications
Authors: Wairojjana Nopparat , Rehman Habib ur , Argyros Ioannis K. , Pakkaranang Nuttapol
Published: August 2020

Several methods have been put forward to solve equilibrium problems, in which the two-step extragradient method is very useful and significant. In this article, we propose a new extragradient-like method to evaluate the numerical solution of the pseudomonotone equilibrium in real Hilbert space. This method uses a non-monotonically stepsize technique based on local bifunction values and Lipschitz-type constants. Furthermore, we establish the weak convergence theorem for the suggested method and provide the applications of our results. Finally, several experimental results are reported to see the performance of the proposed method.
Antimicrobial Peptides of Salmonid Fish: From Form to Function
Authors: Brunner Sascha R. , Varga Joseph F. A. , Dixon Brian
Published: August 2020

Antimicrobial peptides (AMPs) are small, usually cationic, and amphiphilic molecules that play a crucial role in molecular and cellular host defense against pathogens, tissue damage, and infection. AMPs are present in all metazoans and several have been discovered in teleosts. Some teleosts, such as salmonids, have undergone whole genome duplication events and retained a diverse AMP repertoire. Salmonid AMPs have also been shown to possess diverse and potent antibacterial, antiviral, and antiparasitic activity and are induced by a variety of factors, including dietary components and specific molecules also known as pathogen-associated molecular patterns (PAMPs), which may activate downstream signals to initiate transcription of AMP genes. Moreover, a multitude of cell lines have been established from various salmonid species, making it possible to study host-pathogen interactions in vitro, and several of these cell lines have been shown to express various AMPs. In this review, the structure, function, transcriptional regulation, and immunomodulatory role of salmonid AMPs are highlighted in health and disease. It is important to characterize and understand how salmonid AMPs function as this may lead to a better understanding of host-pathogen interactions with implications for aquaculture and medicine.
ACE2 Protein Landscape in the Head and Neck Region: The Conundrum of SARS-CoV-2 Infection
Authors: Descamps Géraldine , Verset Laurine , Trelcat Anne , Hopkins Claire , Lechien Jérome R. , Journe Fabrice , Saussez Sven
Published: August 2020

The coronavirus pandemic raging worldwide since December 2019 is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which invades human cells via the angiotensin-converting enzyme 2 (ACE2) receptor. Although it has already been identified in many organs, ACE2 expression remains largely unknown in the head and neck (HN) sphere. Thus, this study aims to investigate its protein expression in several sites of the upper aerodigestive tract in order to highlight potential routes of infection. We compared ACE2 immunohistochemical expression between 70 paraffin-embedded specimens with two different antibodies and reported the quantified expression in each histological location. Surprisingly, we obtained different results depending on the antibody, an absence of labeling having been observed with a monoclonal antibody raised against the extracellular domain, whereas the polyclonal, against the cytoplasmic part of the protein, revealed enriched ACE2 expression, particularly in sinuses, vocal cords, salivary glands and oral cavity epithelial cells. The interpretation of these discordant results has brought several exciting lines of reflection. In conclusion, this study provides possible routes of entry for the SARS-CoV-2 in HN region and, above all, has led us to encourage caution when studying the ACE2 expression which is currently at the center of all attention.
The Heat Shock Protein 27 Immune Complex Enhances Exosomal Cholesterol Efflux
Authors: Shi Chunhua , Alvarez-Olmedo Daiana , Zhang Yuan , Pattar Badal S. B. , O’Brien Edward R.
Published: August 2020

Previously, we demonstrated that Heat Shock Protein 27 (HSP27) reduces the inflammatory stages of experimental atherogenesis, is released by macrophage (MΦ) exosomes and lowers cholesterol levels in atherosclerotic plaques. Recently, we discovered that natural autoantibodies directed against HSP27 enhance its signaling effects, as HSP27 immune complexes (IC) interact at the cell membrane to modulate signaling. We now seek to evaluate the potential role of the HSP27 IC on MΦ exosomal release and cholesterol export. First, in human blood samples, we show that healthy control subjects have 86% more exosomes compared to patients with coronary artery disease (p < 0.0001). Treating human THP-1 MΦ with rHSP27 plus a validated anti-HPS27 IgG antibody increased the abundance of exosomes in the culture media (+98%; p < 0.0001) as well as expression of Flotillin-2, a marker reflective of exosomal release. Exosome cholesterol efflux was independent of Apo-A1. THP-1 MΦ loaded with NBD-labeled cholesterol and treated with the HSP27 IC showed a 22% increase in extracellular vesicles labeled with NBD and a 95% increase in mean fluorescent intensity. In conclusion, exosomal abundance and secretion of cholesterol content increases in response to HSP27 IC treatment, which may represent an important therapeutic option for diseases characterized by cholesterol accumulation.
Research and Development Directions for Design Support Tools for Circular Building
Authors: Cambier Charlotte , Galle Waldo , De Temmerman Niels
Published: August 2020

To support the construction sector in its transition to a circular economy, many design instruments and decision support tools have been and are still being developed. This development is uncoordinated and raises confusion among building designers and advising engineers, slowing down the tools’ adoption in practice. Moreover, it is unclear if the available design tools are able to fulfil the needs of design professionals at all. Therefore, this research identifies the knowledge challenges for the “supply and demand” of design tools for a circular construction practice. It focuses on Flanders, given the importance the topic receives in the region’s policy programme and among practitioners. This study builds on a thorough literature review, and on inventorying and categorising instruments and ongoing developments. By comparing that review with the needs that were identified during interviews with a focus group, it was possible to pinpoint designers’ needs for support tools and outline three urgent research tracks. More generally, it was found that the needs of our focus group are only partially reflected by the available design tools and the ongoing developments. This identified mismatch advocates for a more participatory and practice-oriented research approach when developing design support tools for circular building.
Comparison of Hydrogels for the Development of Well-Defined 3D Cancer Models of Breast Cancer and Melanoma
Authors: Schmid Rafael , Schmidt Sonja K. , Hazur Jonas , Detsch Rainer , Maurer Evelyn , Boccaccini Aldo R. , Hauptstein Julia , Teßmar Jörg , Blunk Torsten , Schrüfer Stefan , Schubert Dirk W. , Horch Raymund E. , Bosserhoff Anja K. , Arkudas Andreas , Kengelbach-Weigand Annika
Published: August 2020

Bioprinting offers the opportunity to fabricate precise 3D tumor models to study tumor pathophysiology and progression. However, the choice of the bioink used is important. In this study, cell behavior was studied in three mechanically and biologically different hydrogels (alginate, alginate dialdehyde crosslinked with gelatin (ADA–GEL), and thiol-modified hyaluronan (HA-SH crosslinked with PEGDA)) with cells from breast cancer (MDA-MB-231 and MCF-7) and melanoma (Mel Im and MV3), by analyzing survival, growth, and the amount of metabolically active, living cells via WST-8 labeling. Material characteristics were analyzed by dynamic mechanical analysis. Cell lines revealed significantly increased cell numbers in low-percentage alginate and HA-SH from day 1 to 14, while only Mel Im also revealed an increase in ADA–GEL. MCF-7 showed a preference for 1% alginate. Melanoma cells tended to proliferate better in ADA–GEL and HA-SH than mammary carcinoma cells. In 1% alginate, breast cancer cells showed equally good proliferation compared to melanoma cell lines. A smaller area was colonized in high-percentage alginate-based hydrogels. Moreover, 3% alginate was the stiffest material, and 2.5% ADA–GEL was the softest material. The other hydrogels were in the same range in between. Therefore, cellular responses were not only stiffness-dependent. With 1% alginate and HA-SH, we identified matrices that enable proliferation of all tested tumor cell lines while maintaining expected tumor heterogeneity. By adapting hydrogels, differences could be accentuated. This opens up the possibility of understanding and analyzing tumor heterogeneity by biofabrication.
Comparison of NGS and MFC Methods: Key Metrics in Multiple Myeloma MRD Assessment
Authors: Kriegsmann Katharina , Hundemer Michael , Hofmeister-Mielke Nicole , Reichert Philipp , Manta Calin-Petru , Awwad Mohamed , Sauer Sandra , Bertsch Uta , Besemer Britta , Fenk Roland , Hänel Mathias , Munder Markus , Weisel Katja , Blau Igor , Neubauer Andreas , Müller-Tidow Carsten , Raab Marc , Goldschmidt Hartmut , Huhn Stefanie ,   for the German-speaking Myeloma Multicenter Group (GMMG)
Published: August 2020

In order to meet the challenges in data evaluation and comparability between studies in multiple myeloma (MM) minimal residual disease (MRD) assessment, the goal of the current study was to provide a step-by-step evaluation of next-generation sequencing (NGS) and multicolor flow cytometry (MFC) data. Bone marrow (BM) sample pairs from 125 MM patients were analyzed by NGS and MFC MM MRD methods. Tumor load (TL) and limit of detection (LOD) and quantification (LOQ) were calculated. The best-fit MRD cut-off was chosen as 1 × 10−5, resulting in an overall 9.6% (n overall = 12 (NGS n = 2, MFC n = 10)) nonassessable cases. The overall concordance rate between NGS and MFC was 68.0% (n = 85); discordant results were found in 22.4% (11.2% (n = 14) of cases in each direction. Overall, 55.1% (n = 60/109) and 49.5% (n = 54/109) of patients with a serological response ≥ very good partial response (VGPR) showed BM MRD negativity by NGS and MFC, respectively. A good correlation in the TL assessed by both techniques was found (correlation coefficient = 0.8, n = 40, p < 0.001). Overall, our study shows good concordance between MM BM MRD status and TL when comparing NGS and MFC at a threshold of 10–5. However, a sufficient number of analyzed events and calculation of MRD key metrics are essential for the comparison of methods and evaluability of data at a specific MRD cut-off.
Organotypic Co-Cultures as a Novel 3D Model for Head and Neck Squamous Cell Carcinoma
Authors: Engelmann Luca , Thierauf Julia , Koerich Laureano Natalia , Stark Hans-Juergen , Prigge Elena-Sophie , Horn Dominik , Freier Kolja , Grabe Niels , Rong Chao , Federspil Philippe , Zaoui Karim , Plinkert Peter K. , Rotter Nicole , von Knebel Doeberitz Magnus , Hess Jochen , Affolter Annette
Published: August 2020

Background: Head and neck squamous cell carcinomas (HNSCC) are phenotypically and molecularly heterogeneous and frequently develop therapy resistance. Reliable patient-derived 3D tumor models are urgently needed to further study the complex pathogenesis of these tumors and to overcome treatment failure. Methods: We developed a three-dimensional organotypic co-culture (3D-OTC) model for HNSCC that maintains the architecture and cell composition of the individual tumor. A dermal equivalent (DE), composed of healthy human-derived fibroblasts and viscose fibers, served as a scaffold for the patient sample. DEs were co-cultivated with 13 vital HNSCC explants (non-human papillomavirus (HPV) driven, n = 7; HPV-driven, n = 6). Fractionated irradiation was applied to 5 samples (non-HPV-driven, n = 2; HPV-driven n = 3). To evaluate expression of ki-67, cleaved caspase-3, pan-cytokeratin, p16INK4a, CD45, ∝smooth muscle actin and vimentin over time, immunohistochemistry and immunofluorescence staining were performed Patient checkup data were collected for up to 32 months after first diagnosis. Results: All non-HPV-driven 3D-OTCs encompassed proliferative cancer cells during cultivation for up to 21 days. Proliferation indices of primaries and 3D-OTCs were comparable and consistent over time. Overall, tumor explants displayed heterogeneous growth patterns (i.e., invasive, expansive, silent). Cancer-associated fibroblasts and leukocytes could be detected for up to 21 days. HPV DNA was detectable in both primary and 3D-OTCs (day 14) of HPV-driven tumors. However, p16INK4a expression levels were varying. Morphological alterations and radioresistant tumor cells were detected in 3D-OTC after fractionated irradiation in HPV-driven and non-driven samples. Conclusions: Our 3D-OTC model for HNSCC supports cancer cell survival and proliferation in their original microenvironment. The model enables investigation of invasive cancer growth and might, in the future, serve as a platform to perform sensitivity testing upon treatment to predict therapy response.
MiRNA let-7 from TPO(+) Extracellular Vesicles is a Potential Marker for a Differential Diagnosis of Follicular Thyroid Nodules
Authors: Zabegina Lidia , Nazarova Inga , Knyazeva Margarita , Nikiforova Nadezhda , Slyusarenko Maria , Titov Sergey , Vasilyev Dmitry , Sleptsov Ilya , Malek Anastasia
Published: August 2020

Background: The current approaches to distinguish follicular adenomas (FA) and follicular thyroid cancer (FTC) at the pre-operative stage have low predictive value. Liquid biopsy-based analysis of circulating extracellular vesicles (EVs) presents a promising diagnostic method. However, the extreme heterogeneity of plasma EV population hampers the development of new diagnostic tests. We hypothesize that the isolation of EVs with thyroid-specific surface molecules followed by miRNA analysis, may have improved diagnostic potency. Methods: The total population of EVs was isolated from the plasma of patients with FA (n = 30) and FTC (n = 30). Thyroid peroxidase (TPO)-positive EVs were isolated from the total populations using immune-beads. The miRNA from the TPO(+)EVs obtained from the plasma of FA and FTC patients was assayed by RT-PCR. The diagnostic potency of the selected miRNAs was estimated by the receiver operating characteristic (ROC) analysis. Results: TPO(+)EVs can be efficiently isolated by immunobeads. The analysis of Let-7 family members in TPO(+)EVs allows one to distinguish FA and FTC with high accuracy (area under curve defined by ROC = 0.77–0.84). Conclusion: The isolation of TPO(+)EVs, followed by RT-qPCR analysis of Let-7 family members, may present a helpful approach to manage follicular nodules in the thyroid gland.
Unique Case of Congenital Duodenal Atresia and a Choledochal Cyst and the Hypothesis of Their Embryological Evolution
Authors: Downing Brittany , Bader Mohammad Y. , Morello Frank P. , Kylat Ranjit I.
Published: August 2020

The concomitant occurrence of duodenal atresia (DA) and a choledochal cyst (CC) has rarely been reported. Knowledge of both the presentation and management of this rare co-occurrence is imperative in avoiding potential complications and sequelae, such as biliary metaplasia. Herein we describe a female infant born at 32 weeks gestational age who was diagnosed with duodenal atresia and annular pancreas postnatally, who had subsequent findings of malrotation and a choledochal cyst, as seen from contrast imaging. Uncomplicated repair of the DA and obstruction was performed at 4 days of life. She re-presented 2 years later with non-bloody, nonbilious emesis and was found to have elevated amylase, lipase and liver enzymes. Imaging revealed dilated intra-hepatic ducts, a distended gallbladder and a large choledochal cyst. She underwent a cholecystostomy tube placement followed by a definitive choledochal cyst excision with immediate improvement following surgery and full resolution of symptoms before discharge.
Signaling Pathways Involved in the Development of Bronchopulmonary Dysplasia and Pulmonary Hypertension
Authors: Mathew Rajamma
Published: August 2020

The alveolar and vascular developmental arrest in the premature infants poses a major problem in the management of these infants. Although, with the current management, the survival rate has improved in these infants, but bronchopulmonary dysplasia (BPD) is a serious complication associated with a high mortality rate. During the neonatal developmental period, these infants are vulnerable to stress. Hypoxia, hyperoxia, and ventilation injury lead to oxidative and inflammatory stress, which induce further damage in the lung alveoli and vasculature. Development of pulmonary hypertension (PH) in infants with BPD worsens the prognosis. Despite considerable progress in the management of premature infants, therapy to prevent BPD is not yet available. Animal experiments have shown deregulation of multiple signaling factors such as transforming growth factorβ (TGFβ), connective tissue growth factor (CTGF), fibroblast growth factor 10 (FGF10), vascular endothelial growth factor (VEGF), caveolin-1, wingless & Int-1 (WNT)/β-catenin, and elastin in the pathogenesis of BPD. This article reviews the signaling pathways entailed in the pathogenesis of BPD associated with PH and the possible management.
Statistical Steady-State Stability Analysis for Transmission System Planning for Offshore Wind Power Plant Integration
Authors: Sajadi Amirhossein , Clark Kara , Loparo Kenneth A.
Published: August 2020

This paper presents a statistical steady-state stability analysis for transmission system planning studies in order to identify operational issues inherent in the integration of offshore wind power plants. It includes normal and contingency operation. This study considers the integration of a 1000-MW offshore wind power plant into the FirstEnergy/PJM service territory in the U.S. Great Lakes region as a case study and uses a realistic computer model of the U.S. Eastern Interconnection, a 63,000-bus test system. The results show the utility of this statistical analysis tool and its effectiveness in identification of the operational impacts as a result of the integration of offshore wind power plant.
Use of Flue Gas Desulfurization Gypsum, Construction and Demolition Waste, and Oil Palm Waste Trunks to Produce Concrete Bricks
Authors: Phutthimethakul Lalitsuda , Kumpueng Park , Supakata Nuta
Published: August 2020

This research aims to study the utilization of waste from power plants, construction and demolition, and agriculture by varying the ratios of flue-gas desulfurization (FGD) gypsum, construction and demolition waste (CDW), and oil palm trunks (OPT) in concrete production. This research used these as the raw materials for the production of concrete bricks of 15 × 15 × 15 cm. There were 12 ratios of concrete brick, fixing 5.5 wt% of FGD gypsum to replace Portland cement and substituting coarse sand with 0 wt%, 25 wt%, 50 wt%, or 75 wt% of CDW, and gravel with 0 wt%, 0.5 wt%, and 1 wt% of OPT. The initial binder:fine aggregate:coarse aggregate ratio was 1:2:4 and the water to cement ratio was 0.5, curing in water at room temperature for 28 days. Then, all concrete brick specimens were tested for compressive strength and water absorption. From the experiment, it was found that the highest compressive strength of concrete brick specimens was 45.18 MPa, which was produced from 5.5% gypsum without CDW and OPT, while 26.84 MPa was the lowest compressive strength obtained from concrete bricks produced from 5.5% FGD gypsum, 75% CDW, and 1% OPT. In terms of usage, all proportions can be applied in construction and building work because the compressive strength and water absorption were compliant with the Thai Industrial Standard TIS 57-2530 and TIS 60-2516.
Ice Detection on Aircraft Surface Using Machine Learning Approaches Based on Hyperspectral and Multispectral Images
Authors: Musci Maria Angela , Mazzara Luigi , Lingua Andrea Maria
Published: August 2020

Aircraft ground de-icing operations play a critical role in flight safety. However, to handle the aircraft de-icing, a considerable quantity of de-icing fluids is commonly employed. Moreover, some pre-flight inspections are carried out with engines running; thus, a large amount of fuel is wasted, and CO2 is emitted. This implies substantial economic and environmental impacts. In this context, the European project (reference call: MANUNET III 2018, project code: MNET18/ICT-3438) called SEI (Spectral Evidence of Ice) aims to provide innovative tools to identify the ice on aircraft and improve the efficiency of the de-icing process. The project includes the design of a low-cost UAV (uncrewed aerial vehicle) platform and the development of a quasi-real-time ice detection methodology to ensure a faster and semi-automatic activity with a reduction of applied operating time and de-icing fluids. The purpose of this work, developed within the activities of the project, is defining and testing the most suitable sensor using a radiometric approach and machine learning algorithms. The adopted methodology consists of classifying ice through spectral imagery collected by two different sensors: multispectral and hyperspectral camera. Since the UAV prototype is under construction, the experimental analysis was performed with a simulation dataset acquired on the ground. The comparison among the two approaches, and their related algorithms (random forest and support vector machine) for image processing, was presented: practical results show that it is possible to identify the ice in both cases. Nonetheless, the hyperspectral camera guarantees a more reliable solution reaching a higher level of accuracy of classified iced surfaces.
Polygenic Adaptation in a Population of Finite Size
Authors: Stephan Wolfgang , John Sona
Published: August 2020

Polygenic adaptation in response to selection on quantitative traits has become an important topic in evolutionary biology. Here we review the recent literature on models of polygenic adaptation. In particular, we focus on a model that includes mutation and both directional and stabilizing selection on a highly polygenic trait in a population of finite size (thus experiencing random genetic drift). Assuming that a sudden environmental shift of the fitness optimum occurs while the population is in a stochastic equilibrium, we analyze the adaptation of the trait to the new optimum. When the shift is not too large relative to the equilibrium genetic variance and this variance is determined by loci with mostly small effects, the approach of the mean phenotype to the optimum can be approximated by a rapid exponential process (whose rate is proportional to the genetic variance). During this rapid phase the underlying changes to allele frequencies, however, may depend strongly on genetic drift. While trait-increasing alleles with intermediate equilibrium frequencies are dominated by selection and contribute positively to changes of the trait mean (i.e., are aligned with the direction of the optimum shift), alleles with low or high equilibrium frequencies show more of a random dynamics, which is expected when drift is dominating. A strong effect of drift is also predicted for population size bottlenecks. Our simulations show that the presence of a bottleneck results in a larger deviation of the population mean of the trait from the fitness optimum, which suggests that more loci experience the influence of drift.
Design of True Time Delay Millimeter Wave Beamformers for 5G Multibeam Phased Arrays
Authors: Lialios Dimitrios I. , Ntetsikas Nikolaos , Paschaloudis Konstantinos D. , Zekios Constantinos L. , Georgakopoulos Stavros V. , Kyriacou George A.
Published: August 2020

Millimeter wave (mm-Wave) technology is likely the key enabler of 5G and early 6G wireless systems. The high throughput, high capacity, and low latency that can be achieved, when mm-Waves are utilized, makes them the most promising backhaul as well as fronthaul solutions for the communication between small cells and base stations or between base stations and the gateway. Depending on the channel properties different communication systems (e.g., beamforming and MIMO) can accordingly offer the best solution. In this work, our goal is to design millimeter wave beamformers for switched beam phased arrays as hybrid beamforming stages. Specifically, three different analog beamforming techniques for the frequency range of 27–33 GHz are presented. First, a novel compact multilayer Blass matrix is proposed. Second, a modified dummy-ports free, highly efficient Rotman lens is introduced. Finally, a three-layer true-time-delay tree topology inspired by microwave photonics is presented.
How Much Electricity Sharing Will Electric Vehicle Owners Allow from Their Battery? Incorporating Vehicle-to-Grid Technology and Electricity Generation Mix
Authors: Maeng Kyuho , Ko Sungmin , Shin Jungwoo , Cho Youngsang
Published: August 2020

Global trends and prospects of environmentally friendly transportation have helped to popularize electric vehicles (EVs). With the spread of EVs, vehicle-to-grid (V2G) technology is gaining importance for its role in connecting the electricity stored in the battery of EVs to a grid-like energy storage system (ESS). Electricity generation mix and battery for V2G energy storage have a decisive effect on the stabilization of a V2G system, but no attempt has been made. Therefore, this study analyzes consumer preference considering the electricity generation mix and battery for the V2G. We conduct a conjoint survey of a 1000 South Koreans and employ the multiple discrete-continuous extreme value model. The results show that drivers prefer plug-in hybrid- and battery EVs to other vehicles. Additionally, findings show that driver’s utility changes at 27.9% of the battery allowance for V2G system and it becomes positive after 55.7%. Furthermore, we conduct a scenario analysis considering the electricity generation mix (more traditional vs. renewable) and battery allowance. Based on this analysis, we suggest some policies and corporate strategies to support the success of the V2G market depending on energy policies and battery allowance level.
Halide Perovskite Single Crystals: Optoelectronic Applications and Strategical Approaches
Authors: Zhang Yurou , Lyu Miaoqiang , Qiu Tengfei , Han Ekyu , Kim Il Ku , Jung Min-Cherl , Ng Yun Hau , Yun Jung-Ho , Wang Lianzhou
Published: August 2020

Halide perovskite is one of the most promising semiconducting materials in a variety of fields such as solar cells, photodetectors, and light-emitting diodes. Lead halide perovskite single crystals featuring long diffusion length, high carrier mobility, large light absorption coefficient and low defect density, have been attracting increasing attention. Fundamental study of the intrinsic nature keeps revealing the superior optoelectrical properties of perovskite single crystals over their polycrystalline thin film counterparts, but to date, the device performance lags behind. The best power conversion efficiency (PCE) of single crystal-based solar cells is 21.9%, falling behind that of polycrystalline thin film solar cells (25.2%). The oversized thickness, defective surfaces, and difficulties in depositing functional layers, hinder the application of halide perovskite single crystals in optoelectronic devices. Efforts have been made to synthesize large-area single crystalline thin films directly on conductive substrates and apply defect engineering approaches to improve the surface properties. This review starts from a comprehensive introduction of the optoelectrical properties of perovskite single crystals. Then, the synthesis methods for high-quality bulk crystals and single-crystalline thin films are introduced and compared, followed by a systematic review of their optoelectronic applications including solar cells, photodetectors, and X-ray detectors. The challenges and strategical approaches for high-performance applications are summarized at the end with a brief outlook on future work.
Impacts of Investment Cost, Energy Prices and Carbon Tax on Promoting the Combined Cooling, Heating and Power (CCHP) System of an Amusement Park Resort in Shanghai
Authors: Zhang Liting , Gao Weijun , Yang Yongwen , Qian Fanyue
Published: August 2020

Poor economic performance has limited the diffusion of the combined cooling, heating, and power (CCHP) system. Various factors influence the economic performance of the CCHP system. To analyze the impacts of these different factors and promote the CCHP system, this study evaluated its comprehensive performance through a multi-criteria method, using an amusement park resort in Shanghai as a research case. First, three CCHP systems with different penetration rates were presented and simulated in a transient simulation model for comparison. The economic and environmental performance of these different penetration CCHP systems were evaluated based on the dynamic payback period and carbon dioxide emissions. The impacts of investment cost, energy prices, investment subsidy and a carbon tax on the economic performance of the three systems were discussed, and a sensitivity analysis was used to compare these factors. The results show that the current subsidy can reduce the economic gap between the CCHP system and the conventional system, but it still needs to be increased by 1.71 times to achieve market competitiveness of the CCHP system with 100% penetration under the current investment cost and energy prices. In addition, the introduction of a carbon tax could accelerate the promotion of the CCHP system. When the carbon tax reaches 25 $/ton, the CCHP system becomes the best choice of energy supply system.
Sustainable Development and Industry 4.0: A Bibliometric Analysis Identifying Key Scientific Problems of the Sustainable Industry 4.0
Authors: Gajdzik Bożena , Grabowska Sandra , Saniuk Sebastian , Wieczorek Tadeusz
Published: August 2020

The main aim of the manuscript is the identification of key research problems in the field of sustainable development, in the era of implementing the Industry 4.0 concept. The manuscript presents results of the bibliometric analysis in the subject: “Sustainable Industry 4.0”. The bibliometric analysis was realized in three segments: Sustainability, Industry 4.0 and Sustainable Industry 4.0. In the analysis, the following databases were used: Web of Science (WoS), Scopus, Google Scholar. The main purpose of the analysis was to outline the dynamics of publications in the categories: citation, author, country, type document, science field, research area. The review of sources carried out in this way allowed us to identify key research areas and confirm the research thesis adopted in the manuscript. The research thesis: Sustainable Industry 4.0 allows the integration of the Industry 4.0 concept with sustainable development goals. The article is dedicated especially to scientists looking for still unsolved research problems in the implementation of sustainable Industry 4.0. Furthermore, the manuscript could be an inspiration for scientists, stakeholders, practitioners and governments to complete today’s knowledge about the problems of sustainability in Industry 4.0.
Innovative Hydrodynamic Disintegrator Adjusted to Agricultural Substrates Pre-treatment Aimed at Methane Production Intensification—CFD Modelling and Batch Tests
Authors: Zubrowska-Sudol Monika , Dzido Aleksandra , Garlicka Agnieszka , Krawczyk Piotr , Stępień Michał , Umiejewska Katarzyna , Walczak Justyna , Wołowicz Marcin , Sytek-Szmeichel Katarzyna
Published: August 2020

The study objective was to adjust the hydrodynamic disintegrator dedicated to sewage sludge pre-treatment (HDS) to work with agricultural substrate. This involved the development and implementation of a mathematical model of flow via the device’s domain. An innovative disintegrator (HAD—hydrodynamic disintegrator for agriculture) was designed, built, and tested based on the obtained results. The main improvements to the HDS include the implementation of shredding knives in order to overcome clogging by crushed substrate, and the application of ribs in the recirculation zone, contributing to the development of an additional structure damage zone. The challenge of this study was also to determine the operating parameters of the HDA that would provide for an increase in methane production with positive energy balance. The testing procedures, for which maize silage was selected, involved batch disintegration tests and biochemical methane potential tests. No clogging of rotor or spontaneous shutting off of the device, in other words, problems that had occurred in the HDS, were observed. The applied pre-treatment method permitted an increase in the methane potential of maize silage by 34.4%, 27.0%, and 21.6%, respectively for samples disintegrated at energy densities of 10 kJ/L, 20 kJ/L, and 35 kJ/L with net energy profit.
Electricity Generation from Renewable Energy Sources in Poland as a Part of Commitment to the Polish and EU Energy Policy
Authors: Paska Józef , Surma Tomasz , Terlikowski Paweł , Zagrajek Krzysztof
Published: August 2020

The aim of this paper is to present the state of development of renewable energy sources (RES) in Poland in accordance with the obligations of European Union energy policy. The EU Member States are obliged to adopt different support mechanisms for the development of renewable energy sources, and in consequence to achieve their Directive’s targets. Poland, being a Member State of the EU since 2004, has accepted a target of a 15% share of energy generated from renewable energy sources in final energy consumption, including 19.3% from renewable electricity until 2020. Due to the difficulties with target achievement, the authors found it reasonable to analyze the challenge of RES development in Poland. The article presents energy policy in the EU, as well as the review of measures implemented for renewable energy development. The current state of and perspectives on using renewable energy sources in Poland and in the EU are also depicted. In the article, the authors analyze the relation between reference prices at dedicated RES auctions in Poland and the levelized cost of electricity (LCOE). The paper also provides a description of the renewable energy sources’ development in three areas: electricity, heat and transport biofuels. Its main content, though, refers to the generation of electricity from renewable energy sources.
VSG Control Strategy Incorporating Voltage Inertia and Virtual Impedance for Microgrids
Authors: Ke Zipeng , Dai Yuxing , Peng Zishun , Zeng Guoqiang , Wang Jun , Li Minying , Ning Yong
Published: August 2020

Virtual synchronous generator (VSG) control lacks voltage inertia and powerful decoupling capabilities. The voltage of the distributed generator (DG) unit controlled by the VSG will be easily affected by power fluctuations and high-frequency noise, and the DG coupling usually makes the VSG control effect unsatisfactory. In order to effectively reduce power fluctuations, the influence of high-frequency noise on voltage, the influence of coupling on the power regulation, and effectively improve the economy of the economic system, the improved VSG control that combines voltage inertia and virtual impedance is proposed in this paper. The second-order inertia in the proposed VSG control strategy can minimize the voltage change rate and filter high-frequency noise from the excitation and virtual impedance. The virtual impedance in the proposed VSG control strategy can simulate the actual impedance to change the line characteristics, so the coupling of the DG unit can be reduced. Experimental results based on the microgrid platform prove the feasibility of improving the VSG control.
AC–DC Flyback Dimmable LED Driver with Low-Frequency Current Ripple Reduced and Power Dissipation in BJT Linearly Proportional to LED Current
Authors: Yau Yeu-Torng , Hwu Kuo-Ing , Liu Kun-Jie
Published: August 2020

In this paper, a dimmable light-emitting diode (LED) driver, along with the low-frequency current ripple decreased and the bipolar junction transistor (BJT) power dissipation reduced, is developed. This driver is designed based on a single-stage flyback converter. On the one hand, the low-frequency output current ripple reduction is based on the physical behavior of the linear current regulator. On the other hand, when the voltage across the LED string is decreased/increased due to dimming or temperature, the output voltage of the flyback converter will be automatically regulated down/up, thereby making the power dissipation in the BJT linearly proportional to the LED current. By doing so, not only the power loss in the linear current regulator will be decreased as the LED current is decreased or the LED temperature rises, but also the output current ripple can be reduced. Furthermore, the corresponding power factor (PF) is almost not changed, and the total harmonic distortion (THD) is improved slightly. In addition, the LED dimming is based on voltage division. Eventually, a 30 W LED driver, with an input voltage range from 85 to 295 Vrms and with 24 LEDs in series used as a load, is developed, and accordingly, the feasibility of the proposed LED driver is validated by experimental results.