bluuebunny/crossref_metadata_2025 huggingface dataset:
Adrenal Venous Sampling Could Be Omitted before Surgery in Patients with Conn’s Adenoma Confirmed by Computed Tomography and Higher Normal Aldosterone Concentration after Saline Infusion Test
Authors: Holaj Robert , Waldauf Petr , Wichterle Dan , Kvasnička Jan , Zelinka Tomáš , Petrák Ondřej , Krátká Zuzana , Forejtová Lubomíra , Kaván Jan , Widimský Jiří
Published: July 2022

Purpose: Adrenal venous sampling (AVS) performed to distinguish unilateral and bilateral primary aldosteronism (PA) is invasive and poorly standardized. This study aimed to identify non-invasive characteristics that can select the patients with unilateral PA who could bypass AVS before surgery. Methods: A single-center study collected a total of 450 patients with PA. Development and validation cohorts included 242 and 208 patients. The AVS was successful in 150 and 138 patients from the cohorts, and the unilateral PA was found in 96 and 94 patients, respectively. Clinical factors independently associated with lateralized AVS in multivariable logistic regression were used to construct a unilateral PA prediction score (SCORE). Results: The proposed SCORE was calculated as a sum of the prevalence of adrenal nodule on computed tomography (2 points) and plasma/serum aldosterone concentration ≥ 165 ng/L after the saline infusion test (SIT) (1 point). Importantly, the SCORE = 3 points identified 48% of unilateral PA patients with a specificity of 100% in the development cohort. The zero rate of false-positive classifications was preserved with the same cut-off value in the validation cohort. Conclusions: AVS could be omitted before surgery in patients with typical Conn´s adenoma provided the aldosterone concentration ≥ 165 ng/L after the SIT.
Identifying Obstructive Sleep Apnoea in Patients with Empty Nose Syndrome
Authors: Huang Chien-Chia , Wu Pei-Wen , Chuang Chi-Cheng , Lee Cheng-Chi , Lee Yun-Shien , Chang Po-Hung , Fu Chia-Hsiang , Huang Chi-Che , Lee Ta-Jen
Published: July 2022

Obstructive sleep apnoea (OSA) is characterised by repetitive episodes of upper airway collapse and breathing cessation during sleep. Empty nose syndrome (ENS) is a surgically iatrogenic phenomenon of paradoxical nasal obstruction despite an objectively patent nasal airway. This study aimed to investigate sleep quality and the presence of OSA in ENS patients. Forty-eight ENS patients underwent full-night polysomnography. Total nasal resistance (TNR) was determined using anterior rhinomanometry. Symptoms and quality of life were evaluated by the empty nose syndrome 6-item questionnaire (ENS6Q), Sino-Nasal Outcome Test-22 (SNOT-22), and Epworth Sleepiness Scale questionnaires (ESS). Fourteen, twelve, and fourteen patients had mild, moderate, and severe OSA, respectively. The apnoea–hypopnoea index (AHI) and the lowest SpO2 were 23.8 ± 22.4/h and 85.9 ± 11.1%, respectively. N1, N2, N3 and rapid-eye-movement sleep comprised 30.2 ± 16.9%, 47.3 ± 15.5%, 2.1 ± 5.4%, and 20.0 ± 8.1% of the total sleep time. Body mass index, neck circumference, serum total immunoglobulin E, and ENS6Q score were significantly associated with AHI in the regression analysis. The ENS6Q scores correlated positively with AHI, arousal index, and ESS score, but negatively with TNR. ENS patients showed a high OSA prevalence and significant sleep impairment. The extent of OSA was associated with obesity levels and ENS symptom severity. The ENS6Q scores correlated negatively with nasal resistance, and positively with arousal frequency and daytime sleepiness. The recognition of individuals experiencing marked OSA and provision of appropriate intervention is critical to preventing long-term morbidity and mortality, and improving therapeutic outcomes in ENS patients.
Fetal Atrial Flutter Associated with Atrial Septal Aneurysm
Authors: Tongprasert Fuanglada , Luewan Suchaya , Srisupundit Kasemsri , Tongsong Theera
Published: July 2022

Objective: To provide evidence that fetal atrial flutter (AF) caused by atrial septal aneurysm (ASA) can be completely cured by delivery. Methods: Cases series of three fetuses with ASA complicated by AF in late gestation, including hydrops fetalis in one case, were collected and completely followed up. Results: AF in all cases completely disappeared shortly after birth. New insights gained from this study are as follows: (1) PACs or bigeminy associated with ASA can progressively change to AF. (2) AF associated with ASA can cause hydrops fetalis and intrauterine treatment is needed; however, delivery is the definitive treatment. (3) AF associated with ASA completely resolves after birth. This is probably associated with changes in the circulation after birth, with no more blood flow crossing the foramen ovale and no turbulent flow in the ASA with reversal to hit the right atrial wall, activating ectopic pacemakers. Conclusions: This report may have clinical impact because it provides evidence that (1) in case of AF associated with ASA, the prognosis is much better than other causes and delivery should be strongly considered. (2) Fetuses diagnosed with AF should always be checked for the presence of ASA. (3) PAC/bigeminy related to ASA, different from isolated PAC, needs close follow-up for the development of SVT and AF. (4) Fetuses remote from term can benefit from intrauterine treatment to avoid hydrops fetalis, and to prolong gestation for maturity, early delivery is recommended once lung maturity is confirmed.
Development and Evaluation of an Anti-Biotin Interference Method in Biotin-Streptavidin Immunoassays
Authors: Liu Dong , Gebreab Yacob Berhane , Hu Jian , Zhou Lili , Zhang Ning , Tong Hui , Chen Bin , Wang Xiaoqin
Published: July 2022

The strong non-covalent interaction between biotin and streptavidin places streptavidin-based assays, used by many laboratories, at an increased risk of interference by biotin. At present, a few manufacturers have developed fully automated anti-biotin interference methods, although compared with many detection platforms, these remain insufficient. Additionally, there is a need for more methods that can achieve fully automated anti-biotin interference. We sought to develop and evaluate a new biotin interference-resisting method based on a biotin-streptavidin chemiluminescence immunoassay. Streptavidin-coated magnetic microparticles (M) of different concentrations were prepared and tested for their biotin-resistance capabilities in an automated setting (Cobas e 601). The precision, accuracy, and detection capability were also assessed. Higher concentrations of M were found to have a stronger ability to resist biotin interference. A 2.16 mg/mL concentration of M was able to resist 500 ng/mL of biotin in samples while simultaneously having a relatively weak shielding effect on the optical signals. Moreover, the total precision and accuracy of this method, designated as M3, met acceptable standards. M3 has an improved ability to resist biotin interference, can achieve full automation, and its detection performance can meet the general laboratory quality requirements.
The Necessity of Magnetic Resonance Imaging in Congenital Diaphragmatic Hernia
Authors: Neștianu Erick George , Brădeanu Cristina Guramba , Alexandru Dragoș Ovidiu , Vlădăreanu Radu
Published: July 2022

This is a retrospective study investigating the relationship between ultrasound and magnetic resonance imaging (MRI) examinations in congenital diaphragmatic hernia (CDH). CDH is a rare cause of pulmonary hypoplasia that increases the mortality and morbidity of patients. Inclusion criteria were: patients diagnosed with CDH who underwent MRI examination after the second-trimester morphology ultrasound confirmed the presence of CDH. The patients came from three university hospitals in Bucharest, Romania. A total of 22 patients were included in the study after applying the exclusion criteria. By analyzing the total lung volume (TLV) using MRI, and the lung to head ratio (LHR) calculated using MRI and ultrasound, we observed that LHR can severely underestimate the severity of the pulmonary hypoplasia, even showing values close to normal in some cases. This also proves to be statistically relevant if we eliminate certain extreme values. We found significant correlations between the LHR percentage and herniated organs, such as the left and right liver lobes and gallbladder. MRI also provided additional insights, indicating the presence of pericarditis or pleurisy. We wish to underline the necessity of MRI follow-up in all cases of CDH, as the accurate measurement of the TLV is important for future treatment and therapeutic strategy.
Comment on Lee et al. Accuracy of New Deep Learning Model-Based Segmentation and Key-Point Multi-Detection Method for Ultrasonographic Developmental Dysplasia of the Hip (DDH) Screening. Diagnostics 2021, 11, 1174
Authors: Çiftci Sadettin , Aydin Bahattin Kerem
Published: July 2022

We have read the article titled “Accuracy of New Deep Learning Model-Based Segmentation and Key-Point Multi-Detection Method for Ultrasonographic Developmental Dysplasia of the Hip (DDH) Screening” by Lee et al. [...]
Biomarker Dynamics and Long-Term Treatment Outcomes in Breast Cancer Patients with Residual Cancer Burden after Neoadjuvant Therapy
Authors: Holanek Milos , Selingerova Iveta , Fabian Pavel , Coufal Oldrich , Zapletal Ondrej , Petrakova Katarina , Kazda Tomas , Hrstka Roman , Poprach Alexandr , Zvarikova Maria , Bilek Ondrej , Svoboda Marek
Published: July 2022

A residual cancer burden after neoadjuvant therapy (NAT) for breast cancer (BC) is associated with worse treatment outcomes compared to patients who achieved pathologic complete remission. This single-institutional retrospective study of 767 consecutive patients, including 468 patients with assessable residual cancer burden (aRCB) after NAT, with a median follow-up of 36 months, evaluated the biomarkers assessed before NAT from a biopsy and after NAT from a surgical specimen, their dynamics, and effect on long-term outcomes in specific breast cancer subtypes. The leading focus was on proliferation index Ki-67, which was significantly altered by NAT in all BC subtypes (p < 0.001 for HER2 positive and luminal A/B HER2 negative and p = 0.001 for TNBC). Multivariable analysis showed pre-NAT and post-NAT Ki-67 as independent predictors of survival outcomes for luminal A/B HER2 negative subtype. For TNBC, post-NAT Ki-67 was significant alone, and, for HER2 positive, the only borderline association of pre-NAT Ki-67 was observed in relation to the overall survival. Steroid and HER2 receptors were re-assessed just in a portion of the patients with aRCB. The concordance of both assessments was 92.9% for ER status, 80.1% for PR, and 92.2% for HER2. In conclusion, these real-world data of a consecutive cohort confirmed the importance of biomarkers assessment in patients with aRCB, and the need to consider specific BC subtypes when interpreting their influence on prognosis.
Rotor Failure Compensation in a Biplane Quadrotor Based on Virtual Deflection
Authors: Dalwadi Nihal , Deb Dipankar , Ozana Stepan
Published: July 2022

A biplane quadrotor is a hybrid type of UAV that has wide applications such as payload pickup and delivery, surveillance, etc. This simulation study mainly focuses on handling the total rotor failure, and for that, we propose a control architecture that does not only handle rotor failure but is also able to navigate the biplane quadrotor to a safe place for landing. In this structure, after the detection of total rotor failure, the biplane quadrotor will imitate reallocating control signals and then perform the transition maneuver and switch to the fixed-wing mode; control signals are also reallocated. A synthetic jet actuator (SJA) is used as the redundancy that generates the desired virtual deflection to control the pitch angle, while other states are taken care of by the three rotors. The SJA has parametric nonlinearity, and to handle it, an inverse adaptive compensation scheme is applied and a closed-loop stability analysis is performed based on the Lyapunov method for the pitch subsystem. The effectiveness of the proposed control structure is validated using numerical simulation carried out in the MATLAB Simulink.
Energy-Efficient Clustering Mechanism of Routing Protocol for Heterogeneous Wireless Sensor Network Based on Bamboo Forest Growth Optimizer
Authors: Feng Qing , Chu Shu-Chuan , Pan Jeng-Shyang , Wu Jie , Pan Tien-Szu
Published: July 2022

In wireless sensor networks (WSN), most sensor nodes are powered by batteries with limited power, meaning the quality of the network may deteriorate at any time. Therefore, to reduce the energy consumption of sensor nodes and extend the lifetime of the network, this study proposes a novel energy-efficient clustering mechanism of a routing protocol. First, a novel metaheuristic algorithm is proposed, based on differential equations of bamboo growth and the Gaussian mixture model, called the bamboo growth optimizer (BFGO). Second, based on the BFGO algorithm, a clustering mechanism of a routing protocol (BFGO-C) is proposed, in which the encoding method and fitness function are redesigned. It can maximize the energy efficiency and minimize the transmission distance. In addition, heterogeneous nodes are added to the WSN to distinguish tasks among nodes and extend the lifetime of the network. Finally, this paper compares the proposed BFGO-C with three classic clustering protocols. The results show that the protocol based on the BFGO-C can be successfully applied to the clustering routing protocol and can effectively reduce energy consumption and enhance network performance.
Driving Behavior Recognition Algorithm Combining Attention Mechanism and Lightweight Network
Authors: Wang Lili , Yao Wenjie , Chen Chen , Yang Hailu
Published: July 2022

In actual driving scenes, recognizing and preventing drivers’ non-standard driving behavior is helpful in reducing traffic accidents. To resolve the problems of various driving behaviors, a large range of action, and the low recognition accuracy of traditional detection methods, in this paper, a driving behavior recognition algorithm was proposed that combines an attention mechanism and lightweight network. The attention module was integrated into the YOLOV4 model after improving the feature extraction network, and the structure of the attention module was also improved. According to the 20,000 images of the Kaggle dataset, 10 typical driving behaviors were analyzed, processed, and recognized. The comparison and ablation experimental results showed that the fusion of an improved attention mechanism and lightweight network model had good performance in accuracy, model size, and FLOPs.
Evaluating Ecohydrological Model Sensitivity to Input Variability with an Information-Theory-Based Approach
Authors: Farahani Mozhgan A. , Vahid Alireza , Goodwell Allison E.
Published: July 2022

Ecohydrological models vary in their sensitivity to forcing data and use available information to different extents. We focus on the impact of forcing precision on ecohydrological model behavior particularly by quantizing, or binning, time-series forcing variables. We use rate-distortion theory to quantize time-series forcing variables to different precisions. We evaluate the effect of different combinations of quantized shortwave radiation, air temperature, vapor pressure deficit, and wind speed on simulated heat and carbon fluxes for a multi-layer canopy model, which is forced and validated with eddy covariance flux tower observation data. We find that the model is more sensitive to radiation than meteorological forcing input, but model responses also vary with seasonal conditions and different combinations of quantized inputs. While any level of quantization impacts carbon flux similarly, specific levels of quantization influence heat fluxes to different degrees. This study introduces a method to optimally simplify forcing time series, often without significantly decreasing model performance, and could be applied within a sensitivity analysis framework to better understand how models use available information.
The Relationship between Children’s Trait Emotional Intelligence and the Big Five, Big Two and Big One Personality Traits
Authors: López-Cassà Èlia , Pérez-Escoda Núria , Alegre Alberto
Published: July 2022

The irrefutable repercussions of personality and socio-emotional development on children’s learning and psychological well-being justify the relevance for the educational context of delving into the relationship between those two constructs. Therefore, the research presented in this article investigates the link between trait EI and the B5, B2, and B1 (or GFP) personality traits in children between 9 and 13 years of age. We used the Spanish adaptation of the BFQ-NA (Big Five Personality Questionnaire for Children and Adolescents) and the CDE_9-13 (Emotional Development Questionnaire for primary education) with a sample of 259 primary school students. The results showed correlations between the two Big personality factors (B2) and the Big One personality factor (B1) with trait EI. However, the relationship between trait emotional intelligence and the Big Five personality model (B5) was not very high; only two of the five personality traits significantly predicted trait EI. Thus, our results differ from studies conducted with adults, but instead, it is similar to studies conducted with children. Finally, this study reinforces the thesis that trait EI can be considered a synonym of the GFP (General Factor Personality). Consequently, it implies designing and implementing learning and socioemotional development programs during the school years to promote adaptability and social efficacy.
Promoting Equity in Market-Driven Education Systems: Lessons from England
Authors: Kerr Kirstin , Ainscow Mel
Published: July 2022

There is a global trend towards the use of market-driven approaches as a strategy for educational reform. However, this is creating new barriers to the promotion of equity in some countries. Focusing on England as an extreme example of this approach, this paper points to some possibilities for addressing this concern. It reports findings from a series of studies in high poverty contexts in England. These studies have typically involved local educational practitioners and university researchers working together in ways designed to support equitable developments. Lessons from these experiences are identified for market-driven systems internationally. They suggest that to create more equitable arrangements, schools need to work together, and with other organizations, both within and beyond their local areas. They also point to the value of surfacing and using the rich experiential and contextualized knowledge held by practitioners to inform these collaborative developments. Acting on these lessons would mark a significant shift for systems whose current emphasis is on schools working competitively and in isolation, often to the detriment of disadvantaged children and young people.
Differential Reservoir-Forming Mechanisms of the Lower Paleozoic Wufeng-Longmaxi and Niutitang Marine Gas Shales in Northern Guizhou Province, SW China: Theories and Models
Authors: Du Wei , Yang Wei , Li Xingyu , Shi Fulun , Lin Ruiqin , Wang Yisong , Zhang Daquan , Chen Yi , Sun Zhao , Zhao Fuping
Published: July 2022

Fine dissection of microscopic pore structure variations between the Niutitang Formation and the Wufeng-Longmaxi Formation will help to improve the understanding of the underlying geological theory of shale gas in northern Guizhou Province. The stratigraphic, geochemical, physical, and tectonic properties of the two formations vary greatly, resulting in differential development of the microscopic pore structure among reservoirs and, as a result, major variances in gas concentration. To explore the mechanism of differential pore evolution, experimental techniques and instruments such as gas adsorption, liquid intrusion, SEM, XRD, and organic geochemical tests were utilized. The results indicate that the Wufeng-Longmaxi Formation is in a high-maturity stage, while the Niutitang Formation is in an over-mature stage. The latter has a higher TOC content. Both petrographic phases are siliceous shale petrographic phases, and the former has more developed dissolution pores with better pore volume, throat radius, and macropore pore diameters than the latter, as well as organic matter pores, intergranular pores, and microfracture structural parameters, whereas the specific surface area is the opposite. The differences in reservoir pore formation between the two formations were analyzed, and the results showed that the petrographic type, thermal evolution, and tectonic preservation conditions were the primary controlling elements of differential shale gas reservoir formation. A differential reservoir-forming model of the Wufeng-Longmaxi Formation and the Niutitang Formation was constructed, providing a geological and theoretical basis for shale gas geological exploration in northern Guizhou Province.
Computational Fluid Dynamics Simulation Approach for Scrubber Wash Water pH Modelling
Authors: Ristea Marian , Popa Adrian , Scurtu Ionut Cristian
Published: July 2022

In the current article, we will use a CFD approach for the scrubber wash water dilution simulation, by considering the current MEPC (Marine Environment Protection Committee, a subsidiary of IMO—International Maritime Organization) regulations that are in force. The necessity for scrubber wash water pH modelling and its importance in the current environmental framework is emphasized. The presented 3D model is considered as a 400 mm hydraulic diameter fluid domain with two outlets and a discharge water flow rate of 3050 m3/h for the considered pH value of 3, obtained within a state-of-the-art exhaust gas scrubber solution developed by a major EGCS (Exhaust Gas Cleaning Systems) supplier. The CFD study was developed by considering a k-ε turbulence model. In order to achieve accurate results, a structured mesh with two levels of refinement volumes was realized. Based on the obtained data and the various parameters discussed, the paper presents a way to investigate the optimal results for further analytical research of the scrubber washwater dilution process within the exhaust gas cleaning system.
Determination of the Optimum Blend Ratio of Diesel, Waste Oil Derived Biodiesel and 1-Pentanol Using the Response Surface Method
Authors: Yilmaz Nadir , Atmanli Alpaslan , Hall Matthew J. , Vigil Francisco M.
Published: July 2022

Higher alcohols can be included as a third component in biodiesel-diesel mixtures to improve fuel properties and reduce emissions. Determining the optimum concentrations of these fuels according to the purpose of engine use is important both environmentally and economically. In this study, eight different concentrations of diesel (D), waste oil derived biodiesel (WOB), and 1-pentanol (P) ternary mixtures were determined by the design of experimental method (DOE). In order to determine the engine performance and exhaust emission parameters of these fuels, they were tested on a diesel engine with a constant load of 6 kW and a constant engine speed of 1800 rpm. Using the test results obtained, a full quadratic mathematical model with a 95% confidence level was created using the Response Surface Method (RSM) to predict five different output parameters (BSFC, BTE, CO, HC, and NOx) according to the fuel mixture ratios. The R2 accuracy values of the outputs were found at the reliability level. According to the criteria that BTE will be maximum and BSFC, CO, HC, and NOx emissions will be minimum, the optimization determined that the fuel mixture 79.09% D-8.33% WOB-12.58% P concentration (DWOBPopt) will produce the desired result. A low prediction error was obtained with the confirmation test. As a result, it is concluded that the optimized fuel can be an alternative to the commonly accepted B7 blend and can be used safely in diesel engines.
Review of Methodologies for the Assessment of Feasible Operating Regions at the TSO–DSO Interface
Authors: Papazoglou Georgios , Biskas Pandelis
Published: July 2022

The Feasible Operating Region (FOR) is defined as a set of points in the PQ plane that includes all the feasible active and reactive power flows at the Transmission System Operator (TSO)–Distribution System Operator (DSO) interconnection. Recent trends in power systems worldwide increase the need of cooperation between the TSO and the DSO for flexibility provision. In the current landscape, the efficient and accurate estimation of the FOR could unlock the potential of the DSO to provide flexibility to the TSO. To that end, much existing research has tackled the problem of FOR estimation, which is a challenging problem. However, no research that adequately organizes the literature exists. This work aims to fill this gap. Three categories of FOR estimation methods were identified: Geometric, Random Sampling, and Optimization-Based methods. The basic principles behind each method are analyzed and the most significant works involving each method are presented. For the reviewed works, we focus on the types of flexibility providing units included in the FOR estimation, the examination of time dependence, and the monetization of the FOR. Finally, the strengths and weaknesses of each category of methods are compared, providing a holistic review of the available FOR estimation methods.
Synoptic Risk Assessment of Groundwater Contamination from Landfills
Authors: Cerar Sonja , Serianz Luka , Koren Katja , Prestor Joerg , Mali Nina
Published: July 2022

Waste management in Europe has improved in recent years, reducing the amount of waste disposed at landfills. However, there are still many landfills in the countries. It is well known that landfills that do not have measures in place to control leachate entering groundwater can contaminate groundwater long after the landfill is closed. Collecting monitoring results from all landfills allows permitting and management agencies to improve action plans. This relies on a synoptic risk assessment that allows prioritization and milestones to be set for required actions. The developed method of synoptic risk assessment is based on a conceptual model of the landfill and the results of chemical groundwater monitoring tested at 69 landfills in Slovenia. The study confirms that most landfills have a direct or indirect impact on groundwater quality. All landfills were classified into three priority classes on the basis of the synoptic risk assessment. The results show that a total of 24 landfills have a clearly pronounced impact on groundwater. A total of 31 landfills have a less pronounced impact due to the favorable natural attenuation capacity of the soil or the technically appropriate design of the landfill itself. A total of 14 landfills have a less pronounced or negligible impact on groundwater.
Unfolding FDI, Renewable Energy Consumption, and Income Inequality Nexus: Heterogeneous Panel Analysis
Authors: Amin Sakib Bin , Amin Yaron Nezleen , Khandaker Mahatab Kabir , Khan Farhan , Rahman Faria Manal
Published: July 2022

We aim to examine the nexus between Foreign Direct Investment (FDI), Renewable Energy Consumption (REC), and income inequality across selected High-Income Countries (HIC), Upper Middle-Income Countries (UMIC), Lower Middle-Income Countries (LMIC), and Low-Income Countries (LIC). Given the cross-sectional dependency, slope homogeneity, and stationarity properties, we find that the aforementioned variables across all the regions are cointegrated in the long run (LR). For LR estimation, we use the Cross-Sectional-Autoregressive Distributed Lag (CS-ARDL) approach. For the HIC and the UMIC, an increase in FDI increases REC, which in turn causes income inequality to decrease. In the case of LMIC, an increase in REC causes an increase in FDI and decreases income inequality. However, we could not establish a significant relationship with the LIC. We also provide some useful recommendations, such as increased institutional efficiency and promotion of renewable energy investments through higher access to finance.
Stochastic Distributed Control for Arbitrarily Connected Microgrid Clusters
Authors: Khanbaghi Maryam , Zecevic Aleksandar
Published: July 2022

Due to the success of single microgrids, the coming years are likely to see a transformation of the current electric power system to a multiple microgrid network. Despite its obvious promise, however, this paradigm still faces many challenges, particularly when it comes to the control and coordination of energy exchanges between subsystems. In view of that, in this paper we propose an optimal stochastic control strategy in which microgrids are modeled as stochastic hybrid dynamic systems. The optimal control is based on the jump linear theory and is used as a means to maximize energy storage and the utilization of renewable energy sources in islanded microgrid clusters. Once the gain matrices are obtained, the concept of ε-suboptimality is applied to determine appropriate levels of power exchange between microgrids for any given interconnection pattern. It is shown that this approach can be efficiently applied to large-scale systems and guarantees their connective stability. Simulation results for a three microgrid cluster are provided as proof of concept.
A Novel Coordination Mechanism for Connected and Automated Vehicles in the Multi-Intersection Road Network
Authors: Zhang Yuanhao , Zhao Jiabao
Published: July 2022

In recent years, connected automated vehicles (CAVs) have attracted much attention, and the coordination strategy of CAVs in isolated intersections has been widely discussed. However, these algorithms for isolated intersections cannot be directly applied in a multi-intersection road network (MiRN). The coordination strategy in the MiRN requires further investigation. This paper proposes a two-tier strategy for CAV coordination in the MiRN. First, we analyze the coordination problem in isolated intersections and formulate it as a mixed-integer programming problem. Then, for the MiRN, we propose a consensus prediction method to estimate the travel time for CAVs with different paths. Finally, a novel coordination approach is given, showing how to determine the optimal path for CAVs. The experimental results demonstrate the efficiency of the proposed strategy under various traffic flow rates. Compared with the fixed signal time assignment method and the actuated signal time assignment method, our method reduces the average travel time by about 74–83% under different flow rates. We also evaluate the impact of parameters on the strategy’s performance and provide some suggestions for setting these parameters.
Application of Bayesian Networks in Modeling of Underground Gas Storage Energy Security
Authors: Kosowski Piotr , Kosowska Katarzyna , Nawalaniec Wojciech
Published: July 2022

Energy security is a multidimensional and multifaceted concept, therefore defining it is a complex problem. It requires the consideration of a wide set of factors from the fields of economics, geology, ecology and geopolitics, all of which have an influence on energy security or the lack thereof. The article focuses on natural gas, which is a very specific fuel in the European context. It is the most “politicized” source of energy, as a consequence of its growing importance as a transition fuel in the energy transformation process. In order to identify dependencies between variables on the gas market and analyze their impact on it (in particular on underground storage), the authors chose a set of variables and built a Bayesian network. The network is an effective and flexible tool that allows analysis of the relationships between the variables that build them and model their values based on evidence. The article presents two stages of work with the Bayesian network. In the first one, a network was built based on historical data. It shows the relationships between the variables as well as the probability of the value ranges of individual variables. A huge advantage of the presented Bayesian network is that it can be used to model various scenarios on the gas market. Moreover, the ability to make statistical inferences for all its nodes represents a valuable additional feature. Several examples of such inferences are presented in the second stage of the analysis, examining the impact of consumption variability on the level of inventory in underground gas storage facilities, the impact of having an LNG terminal and the share of natural gas in electricity production on the storage capacity of a given country. The use of tools such as Bayesian networks allows us to better discover the interrelationships between variables influencing the energy market, analyze them, and estimate the impact on energy security of distinct scenarios described with specific metrics. A simple example of such a metric, i.e., the minimum level of gas storage at the end of the winter season, as well as its analysis and modeling using a relatively simple Bayesian network, is presented in this article.
Electrochemical Evaluation of Nickel Oxide Addition toward Lanthanum Strontium Cobalt Ferrite Cathode for Intermediate Temperature Solid Oxide Fuel Cell (IT-SOFCS)
Authors: Mohd Abd Fatah Ahmad , Rosli Ahmad , Mohamad Ahmad , Muchtar Andanastuti , S.A. Muhammed , Hamid Noorashrina
Published: July 2022

A mixture of lanthanum strontium cobalt ferrite (LSCF) and nickel oxide (NiO) makes for a desirable cathode material for an IT-SOFC due to its excellent oxygen reduction capability. This study investigates the effect of NiO addition into LSCF cathode on its physical and electrochemical properties. To optimise the amount of NiO addition, both electrochemical impedance spectra and bode phase were used to examine various weight ratios of nickel oxide and LSCF cathode. Brunauer-Emmett-Teller (BET) and thermal analyses validated the electrochemical observation that the LSCF:NiO ratio yields sensible oxygen reduction reaction and stoichiometric findings. Initial characterisation, comprising of phase and bonding analyses, indicated that LSCF-NiO was successfully synthesised at 800 °C using an improved modified sol gel technique. The addition of 5% nickel oxide to LSCF results in the lowest area specific resistance (ASR) value overall. The Bode phase implies that the addition of 5% nickel oxide to LSCF reduces the impedance at low frequencies by 64.28 percent, indicating that a greater oxygen reduction process happened at the cathode. After the addition of 5 wt% NiO, a single LSCF-NiO cell may function at temperatures as low as 650 °C and the LSCF cathode power density is increased by 25.35%. The surface morphology of the LSCF-NiO cathode reveals that the average particle size is less than 100 nm, and mapping analysis demonstrated a homogenous NiO distribution over the cathode layer. Consequently, the synthesis of LSCF-NiO at intermediate temperatures (800–600 °C) revealed outstanding chemical compatibility, bonding characteristics, and electrochemical performance.
Multiobjective Optimization of Cement-Based Panels Enhanced with Microencapsulated Phase Change Materials for Building Energy Applications
Authors: Bre Facundo , Caggiano Antonio , Koenders Eduardus A. B.
Published: July 2022

Thermal energy storage using phase change materials (PCMs) is a promising technology for improving the thermal performance of buildings and reducing their energy consumption. However, the effectiveness of passive PCMs in buildings depends on their optimal design regarding the building typology and typical climate conditions. Within this context, the present contribution introduces a novel multiobjective computational method to optimize the thermophysical properties of cementitious building panels enhanced with a microencapsulated PCM (MPCM). To achieve this, a parametric model for PCM-based cementitious composites is developed in EnergyPlus, considering as design variables the melting temperature of PCMs and the thickness and thermal conductivity of the panel. A multiobjective genetic algorithm is dynamically coupled with the building energy model to find the best trade-off between annual heating and cooling loads. The optimization results obtained for a case study building in Sofia (Bulgaria-EU) reveal that the annual heating and cooling loads have contradictory performances regarding the thermophysical properties studied. A thick MPCM-enhanced panel with a melting temperature of 22 °C is needed to reduce the heating loads, while a thin panel with a melting temperature of 27 °C is required to mitigate the cooling loads. Using these designs, the annual heating and cooling loads decrease by 23% and 3%, respectively. Moreover, up to 12.4% cooling load reduction is reached if the thermal conductivity of the panels is increased. Therefore, it is also concluded that the thermal conductivity of the cement-based panels can significantly influence the effectiveness of MPCMs in buildings.
The Characterization of the Electric Double-Layer Capacitor (EDLC) Using Python/MATLAB/Simulink (PMS)-Hybrid Model
Authors: Tshiani Chrispin Tumba , Umenne Patrice
Published: July 2022

This paper investigates the characterization of an electric double-layer capacitor (EDLC). In this study, the 300 F and 400 F EDLC supercapacitors are connected in a circuit in a laboratory experiment to produce their charge/discharge profiles at a constant current. The acquired charge/discharge profiles were used to determine the mathematical parameters of the EDLCs using the “Faranda model”, or “two-branch model”, of the EDLC. The parameters extracted from the equivalent circuit model were then used as inputs to a designed Python/MATLAB/Simulink (PMS)-hybrid model of an EDLC. This was simulated to obtain charge/discharge profiles. The resulting experimental- and simulated-charge/discharge profiles of the EDLCs were compared with each other, by superimposing their profiles to determine the accuracy of the PMS model. The PMS model was found to be very accurate. The innovation of this work lies in modeling a supercapacitor, mostly in the Python programming language in combination with a MATLAB/Simulink model. The experimental-charge/discharge profiles obtained were used to calculate the equivalent circuit resistance (ESR) and the capacitance of the EDLCs, which were compared with the existing datasheet values of the EDLCs. The characterization of the EDLC supercapacitor was done to derive a flexible PMS model of the EDLC, which can be used in a microgrid hybrid energy-storage system (HESS) to show the potential of the EDLC in improving battery lifespan.
Electric Vehicles Charging Algorithm with Peak Power Minimization, EVs Charging Power Minimization, Ability to Respond to DR Signals and V2G Functionality
Authors: Benysek Grzegorz , Waśkowicz Bartosz , Dylewski Robert , Jarnut Marcin
Published: July 2022

The number of electric vehicles (EV) on the roads, as well as the share of EVs in use, will inevitably increase in coming decades. This creates a number of problems. A large EV fleet is a significant additional load in the power system that is impossible to accurately predict. Another related problem is the limited distribution network capacity, which is not ready for the additional load from the widespread EV infrastructure. There is a need for an EV charging coordination algorithm capable of fulfilling the charging EV needs, while using as low demanded power as possible and using the lowest power values in each EV charging profile. We propose an EV coordinating algorithm that is capable of ensuring that all connected EVs in the considered parking lot will be charged at the user-defined departure time. The algorithm also controls the charging/discharging power of every connected EV in such a way that the parking lot as a whole will use minimal possible peak power while minimizing the charging power of every EV. The proposed algorithm is also capable of responding to demand response (DR) signals. The paper also includes the results of simulation with a statistical summary of the proposed algorithm effectiveness.
Optimization of the Delivery Time within the Distribution Network, Taking into Account Fuel Consumption and the Level of Carbon Dioxide Emissions into the Atmosphere
Authors: Ziółkowski Jarosław , Lęgas Aleksandra , Szymczyk Elżbieta , Małachowski Jerzy , Oszczypała Mateusz , Szkutnik-Rogoż Joanna
Published: July 2022

The evolution of changes in shopping in the modern society necessitates suppliers to seek new solutions consisting of increasing the efficiency of transport processes. When it comes to controlling the flow of goods in modern distribution networks, planning and timely deliveries are of particular importance. The first factor creating a competitive advantage involves the tendency to shorten order delivery times, especially for products with a short shelf life. Shorter delivery times, in turn, extend the period of effective residence of the product “available on the shelf”, increasing the likelihood of its sale. The second component in line with the Sustainable Development Strategy consists of aspects related to the protection of the natural environment, in particular those related to car transport. In this case, the fuel consumption and the level of emitted toxic substances (including carbon dioxide) are analyzed and assessed. Bearing in mind the above, this article presents the problem of optimizing the delivery time within the assumed distribution network and its solution, enabling the company to develop and optimal plan for the transport of products with a short shelf life. The paper proposes a model that takes into account minimization of the delivery time, while estimating the values of fuel consumption and CO2 emissions for the variants considered. The means of transport were medium-duty trucks. Three variants of the assumptions were considered, and algorithms implemented in MS Excel and MATLAB software were used to perform the optimization. Using the MATLAB environment, a more favorable value of the objective function was obtained for the variant without additional constraints. On the other hand, the algorithm implemented in MS Excel more effectively searched the set of acceptable solutions with a larger number of constraining conditions.
Exploring the Causal Relationship among Green Taxes, Energy Intensity, and Energy Consumption in Nordic Countries: Dumitrescu and Hurlin Causality Approach
Authors: Ahmed Nihal , Sheikh Adnan Ahmed , Hamid Zeeshan , Senkus Piotr , Borda Ricardo Cosio , Wysokińska-Senkus Aneta , Glabiszewski Waldemar
Published: July 2022

Improving energy efficiency and minimizing environmental concerns through environmental laws and green taxes are regarded as the primary motivating factors of climate change policy. This analysis clarifies the significance of green taxes in lowering energy use and intensity from 1994 to 2020. As part of our contribution to the literature on energy economics, this study examines how green taxes interact with energy intensity and consumption in four Nordic nations. Environmental policies and sustainable development goals (SDGs) are driving new research into the effects of green taxes on energy consumption and intensity. According to the outcomes of fully modified ordinary least square (FMOLS), panel dynamic ordinary least square (PDOLS), and panel quantile regression, a green tax helps to reduce total energy consumption. It increases energy efficiency by motivating governments, companies, and citizens to encourage innovation in environment-related technology. When it comes to creating a more sustainable environment, the study argues that regulations that ensure the displacement of non-renewable resources while increasing energy efficacy should be implemented.
Evolution of the Pseudo-Components of Heavy Oil during Low Temperature Oxidation Processes
Authors: Zhao Renbao , Wang Tiantian , Chen Lijuan , Pan Jingjun , Li Shutong , Zhao Dong , Chen Long , Wang Jiaying
Published: July 2022

Heavy oil was divided into different pseudo-components according to their boiling ranges through a real-boiling point distillation process, and the oxidation products for pseudo-components with a boiling range higher than 350 °C were systematically investigated during low temperature oxidation (LTO). Kinetic cell (KC) experiments were conducted under different ambient pressure conditions and temperature ranges, and the oxidation products were characterized using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The results indicate that the oxygen addition and cracking reactions typically occur in the temperature intervals of 140–170 °C and 180–220 °C, respectively, at the given heating rate of 3.83 °C/min. Components with the mass-to-charge ratio in the region of 250–450 Da mainly evaporate in the temperature regions of 25–150 °C, which results in losses from the fraction. Considering the gas-liquid multi-phase reaction, the pseudo-components with low boiling range distributed on the surface of the liquid film are prone to generate high molecular weight compounds through oxygen addition. In contrast, the high boiling point range fractions increase in molecular weight through oxygen addition and are then subject to further cracking processes that generate lower molecular weights in the region of 200–400 Da. N1O3- and N1O4- containing compounds were determined by high resolution mass spectra, and these compounds were generated through oxygen addition of basic N1-containing compounds. On the basis of these reactions and the experimental results obtained, some insights related to the LTO of heavy oil, which are highly valuable for ISC field applications, are summarized.
Neutronic Analysis of SiC/SiC Sandwich Cladding Design in APR-1400 under Normal Operation Conditions
Authors: Alaleeli Maithah , Alameri Saeed , Alrwashdeh Mohammad
Published: July 2022

Our aim is to study the neutronic behaviour of potential accident-tolerant fuel (ATF) claddings in a pressurised water reactor under normal operations. This work compares ATF silicon carbide composite (SiC/SiC) cladding to conventional ZIRLOTM cladding in APR-1400. Additionally, a “sandwich” cladding design developed by the CEA is used for SiC/SiC. The design structure includes a liner in between two layers of the composite to ensure leak tightness. The two proposed liners are Niobium (Nb) and Tantalum (Ta). Serpent 2, a Monte Carlo reactor physics lattice code, is employed to model both cladding materials in APR-1400 at three different levels: pin cell, fuel assembly, and core. The criticality, neutron spectrum, actinide inventory, and power distribution as a function of burnup are investigated. The simulations show that SiC/SiC with the Nb liner displays a far superior performance than the Ta liner across all examined characteristics. Ta leads to a harder neutron spectrum and increased Pu-239 content throughout the cycle, while Nb presents negligible effects. In fact, SiC/SiC with the Nb liner performs very similarly to ZIRLOTM at all model levels. The results indicate that, in terms of neutronics, the adoption of the SiC/SiC composite would entail little to no changes to current APR-1400 operations.
Telework: Before and after COVID-19
Authors: Türkeș Mirela Cătălina , Vuță Daniela Roxana
Published: July 2022

Telework is, today, a voluntary form of work organization in which the employee is located outside the employer’s premises, at home or elsewhere, under a telework contract, uses information and communication technologies (ICT) and works according to a predetermined schedule on the basis of an agreed supervisory mechanism and an online reporting system on the work undertaken.