bluuebunny/crossref_metadata_2025 huggingface dataset:
Cannula Fracture during Transoral Endoscopic Thyroidectomy Vestibular Approach: Causes and Prevention
Authors: Liang Tsung-Jung , Liu Shiuh-Inn , Chen I-Shu
Published: June 2022

In the transoral endoscopic thyroidectomy vestibular approach (TOETVA), three oral vestibular incisions are used to access the thyroid. This approach leaves no scar on the body surface; however, unexpected complications may occur. Three patients (two women, one man) underwent TOETVA using the standard three-port technique. Broken cannulas of the 12 mm central port were noted in all cases. All cannulas broke on the ventral side of the distal shaft. The fracture lines were 3–4 cm in length, with some fragments scattered throughout the operative field and oral cavity. The fractures were caused by compression against the mandible while tilting the cannula during surgical manipulation. Male sex, short stature, and protruding chin may be risk factors for cannula fracture in TOETVA. Measures should be taken to prevent this complication, particularly in high-risk patients.
Diagnostic Accuracy of Loop-Mediated Isothermal Amplification Assay for Group B Streptococcus Detection in Recto-Vaginal Swab: Comparison with Polymerase Chain Reaction Test and Conventional Culture
Authors: Sung Ji-Hee , Cha Hyun-Hwa , Lee Nan-Young , Lee Won-Ki , Choi Yeseul , Han Hyung-Soo , Lee Yoo-Young , Chong Gun-Oh , Seong Won-Joon
Published: June 2022

A rapid method for obtaining group B streptococcus (GBS) screening results has been required in the obstetric field. We aimed to determine the diagnostic performance of the Loop-Mediated Isothermal Amplification (LAMP) assay is acceptable compared to the existing polymerase chain reaction (PCR) assay. The study involved 527 pregnant women aged 19 to 44 years. Rectovaginal swabs were collected between 35 and 37 weeks of gestation or prior to impending preterm births or term labor without GBS screening. We presented the diagnostic performance of the LAMP assay with a 95% confidence interval (CI) compared to the PCR and microbiological culture. In total, 115 (21.8%), 115 (21.8%) and 23 (4.4%) patients showed positive results using the LAMP, PCR assay and microbiological culture method, respectively. The LAMP assay showed 100% sensitivity (95% CI, 96.8–100.0), 100% specificity (95% CI, 99.1–100.0) and 100% diagnostic accuracy (95% CI, 99.3–100.0) with the reference being the PCR assay. Meanwhile, the LAMP assay showed 87.0% sensitivity (95% CI, 71.0–100.0), 81.2% specificity (95% CI, 77.6–84.7), and 81.4% diagnostic accuracy (95% CI, 78.0–84.8) with the microbiological culture as a reference. This study presented the LAMP assay as an acceptable method for GBS screening with a similar performance to the existing PCR method.
The Multidisciplinary Approach of Rectal Cancer: The Experience of “COMRE Group” Model
Authors: Scabini Stefano , Romairone Emanuele , Pertile Davide , Massobrio Andrea , Aprile Alessandra , Tagliafico Luca , Soriero Domenico , Mastracci Luca , Grillo Federica , Bacigalupo Almalina , Marrone Ciro , Parodi Maria Caterina , Sartini Marina , Cristina Maria Luisa , Murialdo Roberto , Zoppoli Gabriele , Ballestrero Alberto
Published: June 2022

Background: Total mesorectal excision (TME) is the gold standard to treat locally advanced rectal cancer. This monocentric retrospective study evaluates the results of laparotomic, laparoscopic and robotic surgery in “COMRE GROUP” (REctalCOMmittee). Methods: 327 selected stage I-II-III patients (pts) underwent TME between November 2005 and April 2020 for low or middle rectal cancer; 91 pts underwent open, 200 laparoscopic and 36 robotic TME. Of these, we analyzed the anthropomorphic, intraoperative, anatomopathological parameters and outcome during the follow up. Results: The length of hospital stay was significantly different between robotic TME and the other two groups (8.47 ± 3.54 days robotic vs. 11.93 ± 5.71 laparotomic, p < 0.001; 8.47 ± 3.54 robotic vs. 11.10 ± 7.99 laparoscopic, p < 0.05). The mean number of harvested nodes was higher in the laparotomic group compared to the other two groups (19 ± 9 laparotomic vs. 15 ± 8 laparoscopic, p < 0.001; 19 ± 9 laparotomic vs. 15 ± 7 robotic, p < 0.05). Median follow-up was 52 months (range: 1–169). Overall survival was significantly shorter in the open TME group compared with the laparoscopic one (Chi2 = 13.36, p < 0.001). Conclusions: In the experience of the “COMRE” group, laparoscopic TME for rectal cancer is a better choice than laparotomy in a multidisciplinary context. Robotic TME has a significant difference in terms of hospital stay compared to the other two groups.
Cell-Free DNA for Genomic Analysis in Primary Mediastinal Large B-Cell Lymphoma
Authors: Rivas-Delgado Alfredo , Nadeu Ferran , Andrade-Campos Marcio , López Cristina , Enjuanes Anna , Mozas Pablo , Frigola Gerard , Colomo Luis , Sanchez-Gonzalez Blanca , Villamor Neus , Beà Sílvia , Campo Elías , Salar Antonio , Giné Eva , López-Guillermo Armando , Bellosillo Beatriz
Published: June 2022

High-throughput sequencing of cell-free DNA (cfDNA) has emerged as a promising noninvasive approach in lymphomas, being particularly useful when a biopsy specimen is not available for molecular analysis, as it frequently occurs in primary mediastinal large B-cell lymphoma (PMBL). We used cfDNA for genomic characterization in 20 PMBL patients by means of a custom NGS panel for gene mutations and low-pass whole-genome sequencing (WGS) for copy number analysis (CNA) in a real-life setting. Appropriate cfDNA to perform the analyses was obtained in 18/20 cases. The sensitivity of cfDNA to detect the mutations present in paired FFPE samples was 69% (95% CI: 60–78%). The mutational landscape found in cfDNA samples was highly consistent with that of the tissue, with the most frequently mutated genes being B2M (61%), SOCS1 (61%), GNA13 (44%), STAT6 (44%), NFKBIA (39%), ITPKB (33%), and NFKBIE (33%). Overall, we observed a 75% concordance to detect CNA gains/losses between DNA microarray and low-pass WGS. The sensitivity of low-pass WGS was remarkably higher for clonal CNA (18/20, 90%) compared to subclonal alterations identified by DNA microarray. No significant associations between cfDNA amount and tumor burden or outcome were found. cfDNA is an excellent alternative source for the accurate genetic characterization of PMBL cases.
An Updated Narrative Mini-Review on the Microbiota Changes in Antenatal and Post-Partum Depression
Authors: Doroftei Bogdan , Ilie Ovidiu-Dumitru , Diaconu Roxana , Hutanu Delia , Stoian Irina , Ilea Ciprian
Published: June 2022

Background: Antenatal depression (AND) and post-partum depression (PPD) are long-term debilitating psychiatric disorders that significantly influence the composition of the gut flora of mothers and infants that starts from the intrauterine life. Not only does bacterial ratio shift impact the immune system, but it also increases the risk of potentially life-threatening disorders. Material and Methods: Therefore, we conducted a narrative mini-review aiming to gather all evidence published between 2018–2022 regarding microflora changes in all three stages of pregnancy. Results: We initially identified 47 potentially eligible studies, from which only 7 strictly report translocations; 3 were conducted on rodent models and 4 on human patients. The remaining studies were divided based on their topic, precisely focused on how probiotics, breastfeeding, diet, antidepressants, exogenous stressors, and plant-derived compounds modulate in a bidirectional way upon behavior and microbiota. Almost imperatively, dysbacteriosis cause cognitive impairments, reflected by abnormal temperament and personality traits that last up until 2 years old. Thankfully, a distinct technique that involves fecal matter transfer between individuals has been perfected over the years and was successfully translated into clinical practice. It proved to be a reliable approach in diminishing functional non- and gastrointestinal deficiencies, but a clear link between depressive women’s gastrointestinal/vaginal microbiota and clinical outcomes following reproductive procedures is yet to be established. Another gut-dysbiosis-driving factor is antibiotics, known for their potential to trigger inflammation. Fortunately, the studies conducted on mice that lack microbiota offer, without a shadow of a doubt, insight. Conclusions: It can be concluded that the microbiota is a powerful organ, and its optimum functionality is crucial, likely being the missing puzzle piece in the etiopathogenesis of psychiatric disorders.
A Systematic Review of Fault Injection Attacks on IoT Systems
Authors: Gangolli Aakash , Mahmoud Qusay H. , Azim Akramul
Published: June 2022

The field of the Internet of Things (IoT) is growing at a breakneck pace and its applications are becoming increasingly sophisticated with time. Fault injection attacks on IoT systems are aimed at altering software behavior by introducing faults into the hardware devices of the system. Attackers introduce glitches into hardware components, such as the clock generator, microcontroller, and voltage source, which can affect software functioning, causing it to misbehave. The methods proposed in the literature to handle fault injection attacks on IoT systems vary from hardware-based attack detection using system-level properties to analyzing the IoT software for vulnerabilities against fault injection attacks. This paper provides a systematic review of the various techniques proposed in the literature to counter fault injection attacks at both the system level and the software level to identify their limitations and propose solutions to address them. Hybrid attack detection methods at the software level are proposed to enhance the security of IoT systems against fault injection attacks. Solutions to the identified limitations are suggested using machine learning, dynamic code instrumentation tools, hardware emulation platforms, and concepts from the software testing domain. Future research possibilities, such as the use of software fault injection tools and supervised machine learning for attack detection at the software level, are investigated.
A 3D MIMO Channel Model for a High-Speed Train Millimeter Wave Communication System under Cutting and Viaduct Environments
Authors: Assiimwe Eva , Marye Yihenew Wondie
Published: June 2022

Incorporating MIMO technology with 3D geometry-based stochastic models (GBSM) is a promising channel modeling technique for 5G and beyond. These models could be extended to high-speed train (HST) environments at mmWave bands. In this paper, the proposed 3D MIMO model is composed of the line of sight component (LOS), the non-line of sight component (NLOS) from one sphere, and multiple stochastic confocal elliptic cylinders. The model is applied in the viaduct and cutting environments with a time-varying Rician K-factor. The local channel statistical properties such as the auto correlation function, stationarity distance, and the level crossing rate (LCR) are derived and thoroughly investigated at the 41GHz frequency. These properties are compared with the corresponding measured results at the same wave frequency for an HST wireless channel. There is a strong correlation between the results from the derived model and the measured results. Therefore, this model can be extended to be used for viaduct and cutting channel modeling at the mmWave band.
Performance Evaluation of Directional Antennas in ZigBee Networks under NLOS Propagation Conditions
Authors: Azevedo Joaquim Amândio , Santos Filipe Edgar
Published: June 2022

Many authors suggest directional antennas to enhance the transmission performance of ZigBee networks. For line-of-sight propagation, directional antennas can extend the transmission range or reduce the transmit power. Directional antennas may also reduce interference between networks operating in the same frequency channel. However, these antennas may not perform similarly under non-line-of-sight propagation conditions. This work presents a study with ZigBee modules comparing the performance of a directional antenna with an omnidirectional one. The measurements were conducted on a university campus for different propagation outdoor environments. A deconvolution technique was applied to estimate the received signal as a function of the azimuth angle. The results demonstrated that the received power followed the gain difference between antennas only for paths with low attenuation. Considering the same Effective Isotropic Radiated Power (EIRP), the system with directional antennas started to lose packets at the same distance as the omnidirectional antennas. The directional antenna did not allow the increase in the link range compared to the omnidirectional antenna. The power consumption was also measured for different transmit power levels of the ZigBee radio. The study showed that the control circuits of directional antennas typically consume more power than omnidirectional antennas operating at a higher transmit power level.
Recent Advances in Internet of Things and Emerging Social Internet of Things: Vision, Challenges and Trends
Authors: Amin Farhan , Asghar Ikram , Ali Aftab , Hwang Seong-Oun
Published: June 2022

In recent years, the Internet of Things (IoT), together with its related emerging technologies, has been driving a revolution in the way people perceive and interact with the surrounding environment [...]
Creating Comparability among European Neighbourhoods to Enable the Transition of District Energy Infrastructures towards Positive Energy Districts
Authors: Bruck Axel , Casamassima Luca , Akhatova Ardak , Kranzl Lukas , Galanakis Kostas
Published: June 2022

Planning the required energy infrastructure for the energy transition is a crucial task for various neighbourhood concepts, such as positive energy districts. However, energy planning often comes with the challenges of data shortages and a lack of comparability among solutions for different districts. This work aims to enable this comparability by introducing an approach for categorising districts according to parameters that are relevant for the planning of neighbourhood energy infrastructures. Four parameters (climate, floor space index, heating demand and share of residential buildings) and their respective ranges (bands) were derived from the literature. Additionally, this work visualised the combination of all parameter bands across Europe to conveniently showcase districts that are comparable according to the selected parameters. This approach and its visualisation could be used in urban planning to share knowledge from existing energy district projects with those planned in comparable districts.
An Adaptive Hybrid Control of Grid Tied Inverter for the Reduction of Total Harmonic Distortion and Improvement of Robustness against Grid Impedance Variation
Authors: Muhammad Tila , Khan Adnan Umar , Chughtai Muhammad Tajammal , Khan Reyyan Ahmad , Abid Yousra , Islam Muhammad , Khan Sheroz
Published: June 2022

Background: Grid-tied inverters play an efficient role in the integration of renewable energy resources with utility grids. Motivation: However, the interconnection between power converters and the grid has been seen to be responsible for various stability issues such as weak grid, and under weak grid conditions the injection of power to the grid becomes a challenging task due to continuously varying grid impedance affecting the stability margins as a result. Additionally, the grid impedance-related issues boost the voltage harmonics which further devalue its performance. These voltage harmonics propagate through the Phase-Locked Loop (PLL) circuit to the control unit of the inverter which in turn amplifies the low order harmonics of the inverter. Method: The aim of this research is to introduce a novel strategy that decreases the effect of grid impedance-variations on the performance and stability of an inverter. Hence, an adaptive hybrid mode control technique consisting of two parts is proposed in this research. The current regulator part is implemented in a synchronous reference frame for its gain and time parameters to improve the performance, stability, and response time. The adaptive harmonic compensators are implemented in a stationary reference frame for harmonic compensation purposes. This adaptive nature of harmonic compensator can effectively work in the case of frequency variation where the fixed value based harmonic compensator fails. Results: The adaptive harmonic compensators improve the performance by reducing total harmonic distortion (THD), reduce computation and improve stability when the grid has distorted voltage, variation in grid impedance and frequency. Impact and utility: Our results show that the system becomes less sensitive to grid impedance variations which makes the proposed technique very relevant to the stability performance applications.
Free Energy Changes during Spherical Droplet Deposition—Mechanistic Model
Authors: Michalski Jacek A. , Jakiela Slawomir
Published: June 2022

On the basis of theoretical considerations (mechanistic model), an equation was determined that allowed to calculate the free energy (Helmholtz) of a spherical droplet deposited on a flat surface in a system without external forces. Assuming isochoric and isothermal transformation of the system and a very fast conversion of mechanical energy into heat, the obtained equation allows to determine the trajectory of thermodynamic transformation consisting of the spreading of the droplet on the surface of the substrate. The similarities and differences in the behaviour of spherical droplets described by the mechanistic model and Young’s model, together with its improvements, were discussed. The trajectories of free energy changes during the spreading of droplets in a system in which the adhesive force acting perpendicular to the wetted surface was considered as well.
Latest Energy Storage Trends in Multi-Energy Standalone Electric Vehicle Charging Stations: A Comprehensive Study
Authors: Ali Amad , Shakoor Rabia , Raheem Abdur , Muqeet Hafiz Abd ul , Awais Qasim , Khan Ashraf Ali , Jamil Mohsin
Published: June 2022

The popularity of electric vehicles (EVs) is increasing day by day due to their environmentally friendly operation and high milage as compared to conventional fossil fuel vehicles. Almost all leading manufacturers are working on the development of EVs. The main problem associated with EVs is that charging many of these vehicles from the grid supply system imposes an extra burden on them, especially during peak hours, which results in high per-unit costs. As a solution, EV charging stations integrated with hybrid renewable energy resources (HREs) are being preferred, which utilize multi-energy systems to produce electricity. These charging stations can either be grid-tied or isolated. Isolated EV charging stations are operated without any interconnection to the main grid. These stations are also termed standalone or remote EV charging stations, and due to the absence of a grid supply, storage becomes compulsory for these systems. To attain maximum benefits from a storage system, it must be configured properly with the EV charging station. In this paper, different types of the latest energy storage systems (ESS) are discussed with a comprehensive review of configurations of these systems for multi-energy standalone EV charging stations. ESS in these charging stations is applied mainly in three different configurations, named single storage systems, multi-storage systems, and swappable storage systems. These configurations are discussed in detail with their pros and cons. Some important expectations from future energy storage systems are also highlighted.
Overview of the Role of Energy Resources in Algeria’s Energy Transition
Authors: Himri Youcef , Rehman Shafiqur , Mostafaeipour Ali , Himri Saliha , Mellit Adel , Merzouk Mustapha , Merzouk Nachida Kasbadji
Published: June 2022

Algeria is a wealthy country with natural resources, namely, nuclear, renewable, and non-renewable sources. The non-renewable energy sources are considered the lion’s share for energy production (98%). Algeria’s efforts to ensure and strengthen its energy security will take an important step in the coming decades by commissioning new energy infrastructure based on intensive use of water, coal, nuclear, non-renewable, and renewable sources. The implementation of new power infrastructure is expected to be operational from 2030. The renewable power realization in Algeria is relatively less compared to other African countries, i.e., Morocco, Egypt, South Africa, etc. The total renewable power installed capacity in Algeria reached 686 MW in 2020, as part of its national energy portfolio, although the Algerian government has spent tremendous efforts on introducing new sustainable technologies to enable the transition towards a cleaner and sustainable energy system. Indeed, the country announced its plan to install around 22 GW of renewable energy capacity by 2030. It will include 1 GW bio-power from the waste, 13.5 GW from solar PV, 2 GW from CSP, 15 MW from geothermal, 400 MW cogeneration, and, finally, 5 GW from wind. The scope of the present research provides general information about the usage of energy resources such as fossil, nuclear, and renewable sources in Algeria and also covers the energy supply outlook. The present effort is the first of its kind which discusses the application of the coal and nuclear as clean energy sources as part of renewable energy transition. Additionally, it also includes the description of the existing Algerian energy sector and information about water and water desalination and their usage in other sectors.
Integration of Switched Reluctance Generator in a Wind Energy Conversion System: An Overview of the State of the Art and Challenges
Authors: Touati Zeineb , Pereira Manuel , Araújo Rui Esteves , Khedher Adel
Published: June 2022

This paper presents a technical overview for Switched Reluctance Generators (SRG) in Wind Energy Conversion System (WECS) applications. Several topics are discussed, such as the main structures and topologies for SRG converters in WECS, and the optimization control methods to improve the operational efficiency of SRGs in wind power generation systems. A comprehensive overview including the main characteristics of each SRG converter topology and control techniques were discussed. The analysis presented can also serve as a foundation for more advanced versions of SRG control techniques, providing a necessary basis to spur more and, above all, motivate the younger researchers to study magnetless electric machines, and pave the way for higher growth of wind generators based on SRGs.
Steam Temperature Characteristics in Boiler Water Wall Tubes Based on Furnace CFD and Hydrodynamic Coupling Model
Authors: Guo Xin , Xia Liangwei , Zhao Guangbo , Wei Guohua , Wang Yongjie , Yin Yaning , Guo Jianming , Ren Xiaohan
Published: June 2022

With the development of power plant units of higher capacity and with improved parameters, the proportion of high-capacity units for generating power has increased; this requires large capacity units to take responsibility for power-grid peak shaving. When the boiler operates at low loads, the working fluid in the boiler water wall tubes is subjected to high heat flux in the furnace, which can cause heat transfer deterioration, tube overheating or even leakage. Therefore, it is particularly important to study the reliability of the boiler hydrodynamic cycle during peak shaving (low load operation). This study takes a 1000 MW ultra-supercritical single-reheat Π type boiler with single furnace and double tangential firing as the research object. A furnace Computational Fluid Dynamics (CFD) and hydrodynamic coupling analysis model is established and verified according to the actual operating conditions on site. The calculation results show that the simulated value is in good agreement with the actual operating value. Therefore, the model established in this study can reflect the real situation of the on-site furnace to a certain extent, and has high reliability. Based on the fitting results, the causes of steam temperature deviation of the boiler water wall are analyzed, and measures to reduce the deviation are proposed to provide a necessary basis for power plant operation and boiler design.
Probabilistic Load Profile Model for Public Charging Infrastructure to Evaluate the Grid Load
Authors: Weiß Andreas , Biedenbach Florian , Müller Mathias
Published: June 2022

The shift toward electric mobility in Germany is a major component of the German climate protection program. In this context, public charging is growing in importance, especially in high-density urban areas, which causes an additional load on the distribution grid. In order to evaluate this impact and prevent possible overloads, realistic models are required. Methods for implementing such models and their application in the context of grid load are research topics that are only minorly addressed in the literature. This paper aims to demonstrate the entire process chain from the selection of a modelling method to the implementation and application of the model within a case study. Applying a stochastic approach, charging points are modelled via probabilities to determine the start of charging, plug-in duration, and charged energy. Subsequently, load profiles are calculated, integrated into an energy system model and applied in order to analyze the effects of a high density of public charging points on the urban distribution grid. The case study highlights a possible application of the implemented probabilistic load profile model, but also reveals its limitations. The primary results of this paper are the identification and evaluation of relevant criteria for modelling the load profiles of public charging points as well as the demonstration of the model and its comparison to real charging processes. By publishing the determined probabilities and the model for calculating the charging load profiles, a comprehensive tool is provided.
DNS Study of Spherically Expanding Premixed Turbulent Ammonia-Hydrogen Flame Kernels, Effect of Equivalence Ratio and Hydrogen Content
Authors: Mukundakumar Nithin , Bastiaans Rob
Published: June 2022

In this study, 3D premixed turbulent ammonia-hydrogen flames in air were studied using DNS. Mixtures with 75%, 50% and 25% ammonia (by mole fraction in the fuel mixture) and equivalence ratios of 0.8, 1.0 and 1.2 were studied. The studies were conducted in a decaying turbulence field with an initial Karlovitz number of 10. The flame structure and the influence of ammonia and the equivalence ratio were first studied. It was observed that the increase in equivalence ratio smoothened out the small scale wrinkles while leading to strongly curved leading edges. Increasing the amount of hydrogen in the fuel mixtures also led to increasingly distorted flames. These effects are attributed to local increases in the equivalence ratio due to the preferential diffusion effects of hydrogen. The effects of curvature on the flame chemistry were studied by looking at fuel consumption rates and key reactions. It was observed that the highly mobile H2 and H species were responsible for differential rates of fuel consumption in the positively curved and negatively curved regions of the flame. The indication of a critical amount of hydrogen in the fuel mixture was observed, after which the trends of reactions involving H radical reactions were flipped with respect to the sign of the curvature. This also has implications on NO formation. Finally, the spatial profiles of heat release and temperature for 50% hydrogen were studied, which showed that the flame brush of the lean case increases in width and that the flame propagation is slow for stoichiometric and rich cases attributed to suppression of flame chemistry due to preferential diffusion effects.
Borderline SMOTE Algorithm and Feature Selection-Based Network Anomalies Detection Strategy
Authors: Sun Yong , Que Huakun , Cai Qianqian , Zhao Jingming , Li Jingru , Kong Zhengmin , Wang Shuai
Published: June 2022

This paper proposes a novel network anomaly detection framework based on data balance and feature selection. Different from the previous binary classification of network intrusion, the network anomaly detection strategy proposed in this paper solves the problem of multiple classification of network intrusion. Regarding the common data imbalance of a network intrusion detection set, a resampling strategy generated by random sampling and Borderline SMOTE data is developed for data balance. According to the features of the intrusion detection dataset, feature selection is carried out based on information gain rate. Experiments are carried out on three basic machine learning algorithms (K-nearest neighbor algorithm (KNN), decision tree (DT), random forest (RF)), and the optimal feature selection scheme is obtained.
Lithium-Ion Battery Health Prediction on Hybrid Vehicles Using Machine Learning Approach
Authors: Jafari Sadiqa , Shahbazi Zeinab , Byun Yung-Cheol
Published: June 2022

Efforts to decarbonize the world have shown a quick increase in electric vehicles (EVs), limiting increasing pollution. During this electric transportation revolution, lithium-ion batteries (LIBs) play a vital role in storing energy. To determine the range of an electric vehicle (EV), the state of charge and the state of health (SOH) of the battery pack is essential. Access to high-quality data on battery parameters is a crucial challenge for researchers working in the energy storage domain due primarily to confidentiality constraints on manufacturers of batteries and EVs. This paper proposes a hybrid framework for predicting the state of a lithium-ion battery for electric vehicles (EV). Electric vehicles are growing worldwide because of their environmental and sustainability advantages. Batteries are replacing fossil fuels in electric vehicles. In order to prevent failure, Li-ion batteries in electric vehicles should be operated and controlled in a controlled and progressive manner to ensure increased efficiency and safety. An extreme gradient boosting (XGBoost) algorithm is used in this paper to estimate the state of health (SOH) of lithium-ion batteries used in electric vehicles. The model is subjected to error analysis to optimize the battery’s performance parameter. The model undergoes an error analysis to optimize its performance parameters. Furthermore, a state of health (SOH) estimation method based on the extreme gradient boosting algorithm with accuracy correction is proposed here to improve the accuracy of state of health (SOH) estimation for lithium-ion batteries. To describe the aging process of batteries, we extract several features such as average voltages, voltage differences, current differences, and temperature differences. The extreme gradient boosting (XGBoost) model for estimating the state of health (SOH) of lithium-ion batteries is based on the ensemble learning algorithm’s higher prediction accuracy and generalization ability. Experimental results suggest that the boundary gradient lifting algorithm model is capable of more accurate prediction.
The Cluster Method of Heterogeneous Distributed Units in a Low Voltage Distribution Network
Authors: Wang Tao , Li Hongshan , Song Huihui , Liu Meng , Liu Hongchen
Published: June 2022

With the large amounts of small capacity and heterogeneous distributed electricity units connected to the distribution power network, there exist increasingly complex management challenges. In this paper, a new management scheme that can classify and divide the distributed units according to their adjustable characteristics is proposed, which consequently forms an effective collection of fragmented adjustable ability and promotes the utilization of micropower resources. Inspired by the social division of labor in the biological community, the approach is based on a logical aggregation with the division of labor. A feature extraction method was acquired on the basis of the daily output curve, which reduces the data dimension and, subsequently, clusters the output feature points by the K-means algorithm. The simulation is performed by taking the measured output curve of low voltage distributed units on the low voltage side. The experimental results analyze the characteristics of seven classes of distributed units, allocate two main features, and reorganize them into a cluster; so, the “5-dimensional feature array” is reduced to “2-dimensional feature points”. The results demonstrate that the proposed cluster method can enable the power grid to identify and classify the distributed units automatically.
Symmetry Detection and Topological Synthesis of Mechanisms of Powertrains
Authors: Yang Wenjian , Li Changping
Published: June 2022

The function of vehicle powertrains (including hybrid powertrains) is to transmit power from the power source (engine or electric machine) to driving wheels. The planetary gear train (PGT) is a core structure of mechanisms of powertrains. The detection of topological symmetry is helpful for improving the efficiency of mechanism design. In this paper, we present a fully automatic and reliable method for detecting symmetry of plane kinematic chains and extend this method to symmetry detection and the topological design of mechanisms of powertrains. First, the topological model and adjacency matrix are introduced to represent various kinds of plane kinematic chains. Then, the moment matrix of the kinematic chain is established to obtain link groups, based on which we propose an algorithm to generate the unique numerical code of each link and precisely detect the symmetry. Our method is applied to synthesize different kinds of plane kinematic chains and mechanisms, which can improve the design efficiency of mechanisms of powertrains and other mechanical devices.
Optimization of Pre-Chamber Geometry and Operating Parameters in a Turbulent Jet Ignition Engine
Authors: Dilber Viktor , Sjerić Momir , Tomić Rudolf , Krajnović Josip , Ugrinić Sara , Kozarac Darko
Published: June 2022

A turbulent jet ignition engine enables operation with lean mixtures, decreasing nitrogen oxide (NOX) emissions up to 92%, while the engine efficiency can be increased compared to conventional spark-ignition engines. The geometry of the pre-chamber and engine operating parameters play the most important role in the performance of turbulent jet ignition engines and, therefore, must be optimized. The initial experimental and 3D CFD results of a single-cylinder engine fueled by gasoline were used for the calibration of a 0D/1D simulation model. The 0D/1D simulation model was upgraded to capture the effects of multiple flame propagations, and the evolution of the turbulence level was described by the new K-k-ε turbulence model, which considers the strong turbulent jets occurring in the main chamber. The optimization of the pre-chamber volume, the orifice diameter, the injected fuel mass in the pre-chamber and the spark timing was made over 9 different operating points covering the variation in engine speed and load with the objective of minimizing the fuel consumption while avoiding knock. Two optimization methods using 0D/1D simulations were presented: an individual optimization method for each operating point and a simultaneous optimization method over 9 operating points. It was found that the optimal pre-chamber volume at each operating point was around 5% of the clearance volume, while the favorable orifice diameters depended on engine load, with optimal values around 2.5 mm and 1.2 mm at stoichiometric mixtures and lean mixtures, respectively. Simultaneous optimization of the pre-chamber geometry for all considered operating points resulted in a pre-chamber volume equal to 5.14% of the clearance volume and an orifice diameter of 1.1 mm.
Study on Crack Penetration Induced by Fatigue Damage of Low Permeability Coal Seam under Cyclic Loading
Authors: Jiao Anjun , Tian Shixiang , Lin Huaying
Published: June 2022

For low permeability coal seam permeability is weak, low degree of gas migration, prone to gas accidents and other issues. In this paper, a numerical model is established to simulate the process of hydraulic fracturing under monotonic loading and cyclic loading, and a method of increasing permeability of coal seam by cyclic loading hydraulic fracturing technology is proposed. Combined with similar experiments, the influence of cyclic load and cyclic load applied parameters on the fracturing effect of coal and rock mass was analyzed by applying a cyclic load with a pulse pump. The effect of cyclic load pressure technology on coal seam drainage was analyzed by application in 20915 gas control roadways of a coal mine in Guizhou. The results show that after fracturing, the fracture extends along the weak plane of the prefabricated fracture, the pore pressure in the fracture is high pressure, and the pore pressure around the fracture decreases step by step. Due to the compression of the crack, the energy is transferred to the two ends of the crack. The pore pressure has an irregular oval distribution, and there is stress concentration. The pressure value reaches 41.48 MPa. After the cyclic load was applied to the model, the pressure reached the maximum value of 27.64 MPa at 3.37 s. Compared with the monotonic load, the pressure value was reduced by 46.27%. Through pressure and ringing analysis, the fatigue damage of specimens can be realized under cyclic loading. In the experiment, the unconstrained initiation pressure was 2.48 MPa, but after the constraint was applied, the initiation pressure increased to 4.58 MPa, and the pressure increase reached about 55%. After multiple loading and unloading, the peak pressure of the specimen can be reduced and the number of cracks can be increased. In the experiment, the gas extraction rate of ordinary drilling was maintained at about 0.019 m3/min, and the gas extraction rate of ordinary fracturing drilling fluctuated at 0.025 m3/min after 21 days of gas extraction. The pumping capacity of 15 Hz and 20 Hz cyclic loading fracturing boreholes tended to be stable after 15 days, which were about 0.041 m3/min and 0.062 m3/min, respectively. Cyclic loading hydraulic fracturing is better than monotonic loading hydraulic fracturing, and the lower the cyclic loading frequency, the better the fracturing effect.
Study on Wood in Houses as Carbon Storage to Support Climate Stabilisation: Study in Four Residences around Jakarta Municipal City
Authors: Malik Jamaludin , Supriyanto  , Santoso Adi , Sulastiningsih Ignasia Maria , Supriadi Achmad , Trisatya Deazy Rachmi , Damayanti Ratih , Basri Efrida , Saefudin  , Hastuti Novitri , Prabawa Sigit Baktya , Suhartana Sona , Dungani Rudi
Published: June 2022

Global agreements mandate the international community, including Indonesia, to commit to reducing the risks and impacts of climate change. Indonesia’s Nationally Determined Contributions (NDCs) will contribute to the achievement of the Convention’s goals by reducing greenhouse gas (GHG) emissions and increasing climate resilience. This commitment must be supported by a wide range of actions, including the use of timber. Despite the fact that wood contains carbon, limited information is currently available on the size of the wood utilisation subsector’s contribution to reducing GHG emissions. More research is needed on the magnitude of wood products’ contribution to climate change mitigation. This study assessed the amount of carbon stored in wood used as a building material. Purposive sampling was used to select the cities with rapid housing development surrounding Jakarta’s capital city, i.e., the Bekasi District, East Jakarta City, Depok City, and Bogor District. The amount of carbon stored in wood was calculated according to EN 16449:2014-06 and energy dispersive X-ray spectroscopy (EDS/EDX) analysis. Results show that wood is currently only used in door frames, door leaves, window frames, shutters, and vents. The carbon stored on the components ranges from 450 to 680 kg (average of 554.50 kg) in each housing unit, according to the EN 16449:2014-06 calculation. The weight range is between 130 and 430 kg (average of 400.42 kg) according to EDX/S carbon analysis. With an increase in housing needs of 800,000 units per year, this amount has the potential to store 0.44 million tons of carbon over the lifespan of the products.
Eucalyptus pellita Coppice vs. Seedlings as a Re-Establishment Method in South Sumatra, Indonesia
Authors: Hardiyanto Eko B. , Inail Maydra A. , Mendham Daniel S. , Thaher Erlanda , Sitorus Benardo K.
Published: June 2022

Eucalyptus pellita can be regenerated through coppice. We report on the first known study of full-rotation productivity of E. pellita coppice and seedling re-establishment methods. We conducted this study at a high productivity site in South Sumatra, with the objectives to (1) evaluate the productivity of a first rotation of coppice stand in comparison with a replanted seedling crop, (2) investigate the effect of nitrogen (N) and phosphorus (P) fertiliser application on growth, and (3) examine the effect of timing of coppice stem number reduction on growth. The experiment was laid out in a randomised complete block design replicated five times. At the end of rotation (6 years after establishment) the coppice stand had substantially higher productivity (height 23.7 m, diameter 16.4 cm, volume 269.9 m3 ha−1, and MAI 45.0 m3 ha−1 y−1) compared to the replanted seedling stand (height 20.5 m, diameter 13.8 cm, volume 193.6 m3 ha−1, and MAI 32.3 m3 ha−1 y−1). Coppice stand also had higher biomass production but slightly lower wood density than the seedling stand. Neither stand responded to application of N fertiliser, and only the seedling stand responded positively to P fertiliser addition. Coppice reduction to one stem at 2 months after tree felling produced the stand with slightly greater diameter than that at 4 months after tree felling, but had approximately the same volume.
Response of Spruce Forest Ecosystem CO2 Fluxes to Inter-Annual Climate Anomalies in the Southern Taiga
Authors: Mamkin Vadim , Varlagin Andrej , Yaseneva Irina , Kurbatova Julia
Published: June 2022

Climate extremes and anomalies modify the CO2 ecosystem–atmosphere exchange of the boreal forests and consequently alter the terrestrial carbon stocks and the atmospheric greenhouse gas concentrations. The effects of the anomalous weather conditions on the CO2 net ecosystem exchange (NEE), total ecosystem respiration (TER), and gross primary production (GPP) of the typical southern taiga nemorose spruce forest were analyzed using continuous eddy covariance flux measurements in the 2015–2020 period. The forest was found to be a source of atmospheric CO2 in 2016, 2017, 2019, and 2020 (the mean annual GPP/TER ratio was between 0.87 and 0.97). In 2018, the forest was found to act as a CO2 sink (GPP/TER = 1.47) when a positive temperature anomaly in the growing season was accompanied by a negative precipitation anomaly and increased global radiation. The early start of the CO2 uptake in the anomalously warm winter of 2019/2020 did not result in an increase in the annual GPP/TER ratio (0.90). The comparison of the flux data obtained from the nemorose spruce forest on the well-drained soils with the data obtained from paludified spruce forest in the same landscape showed that the mean annual GPP/TER ratio of the sites alternatively responded to the mentioned anomalies. This study suggests that a variety of soil moisture regimes across the southern taiga spruce forests provide a non-uniformity in the response reactions of the CO2 ecosystem–atmosphere exchange on the climate anomalies.
Potential Role of Gastrointestinal Microbiota in Growth Regulation of Yellowtail Kingfish Seriola lalandi in Different Stocking Densities
Authors: Jiang Yan , Yu Chaoyong , Xu Yongjiang , Liu Xuezhou , Cui Aijun , Wang Bin , Zhou Heting
Published: June 2022

A 90-day study was performed under three different stocking densities, including high density (10,000 fishes/cage), medium density (8000 fishes/cage), and low density (6000 fishes/cage), in a deep-sea net cage for yellowtail kingfish (Seriola lalandi). The physiological characteristics and growth performance were tested, and structural characteristics of the gastrointestinal microbiota were systematically analyzed. The results show that fishes with high density had a lower weight gain rate and a specific growth rate, as well as higher serum cortisol content. The diversity, types and numbers of dominant microbiota with significant differences, and the numbers of shared genera among the different groups all changed. Core genera in the gastrointestinal tract were obtained according to the principles of dominance, commonality, and difference. The changes in the relative abundance of the core genera might be related to the growth and physiological characteristics of the host. The ratio of Firmicutes to Bacteroidetes in the stomach and pyloric caecum, which favors the accumulation of energy by the host from the diet, was higher in the medium-density group than in the other groups. This indicates that the higher density could cause physiological stress and affect growth performance. In order to reduce the resulting growth differences, gastrointestinal microbiota might assist the host in accumulating energy, participating in the energy distribution by adjusting its structure. Based on the growth, physiology, and production practices, the medium density was the appropriate density in this study. This study provides a reference for the improvement of deep-sea culture technology and the promotion of healthy growth through the gastrointestinal microecological regulation of yellowtail kingfish.
Unravelling Stock Spatial Structure of Silverside Odontesthes argentinensis (Valenciennes, 1835) from the North Argentinian Coast by Otoliths Shape Analysis
Authors: Morawicki Santiago , Solimano Patricio J. , Volpedo Alejandra V.
Published: June 2022

The marine silverside (Odontesthes argentinensis) is an euryhaline species, distributed along the southwest coast of the Atlantic Ocean, present in estuaries, brackish coastal lagoons and shallow marine waters. It is a significant economic resource for local fisheries in southern Brazil, Uruguay and Argentina. The aim of this work was to contribute to knowledge on the stock spatial structure of the silverside, using otolith shape analysis, based on samples from nine locations in the Argentinian Sea, covering a large distribution range of the species. A combination of elliptic Fourier descriptors, Wavelet coefficients and otolith Shape indices were explored by multivariate statistical methods. The application of wavelet and combined wavelet, Fourier and Shape Indices were the most effective variables to discriminate between sampling sites (7.42 total error). PERMANOVA analysis of otolith shape revealed multivariate significant differences between north versus south locations (p < 0.0001). The results obtained show that the spatial structure of O. argentinensis presents a North–South gradient with marked differences between the extreme localities of the north (Mar del Plata, Quequén) with more elliptical shapes than those in the south (San Blas, San Antonio Este) and an isolated group conformed by Puerto Lobos.