bluuebunny/crossref_metadata_2025 huggingface dataset:
Numerical Simulation of Thermo-hydraulic Behaviour of Shell and Tube Heat Exchanger Equipped with Segmental Baffle and Helical Baffle
Authors: Hu Bao , Liu Hongjiao , Jin Mei
Published: September 2023

The baffle type and structure are critical to enhancing the comprehensive thermo-hydraulic behavior of shell-and-tube heat exchangers (STHX). In the study, Solidworks software was used to establish three-dimensional mesh models of STHX equipped with the segmental baffle and the continuous helical baffle, respectively. ANSYS software was adopted to study the effects of the baffle type and the baffle geometric parameters on the thermo-hydraulic characteristic of STHXs using the pressure drop of the shell side, the coefficient of heat transfer and isobaric JFP factor as the evaluation characteristics. For segmental baffles, better thermo-hydraulic performance could be obtained with a baffle spacing of 200 mm and a gap height of 0.4 D. For helical baffles, an optimized thermo-hydraulic performance could be obtained with a baffle pitch of 150 mm. By comparing the comprehensive thermo-hydraulic performances of STHXs equipped with two different baffles, it could be concluded that the isobaric JFP
factor of STHX equipped with the helical baffle was 1.18 times that of STHX equipped with the segmental baffle under the different suitable flow rate.
Heat Transfer Enhancement Analysis of Collector Tube in LFR-CSP
Authors: Xu Jianwei , Chen Kang , Chen Pengfei , Niu Dongsheng , Wang Xiao
Published: September 2023

The heat transfer characteristics of the collector tube is one of the cores of a linear Fresnel reflector-solar thermal power generation system (LFR-CSP). In this paper, the heat transfer model of reflective linear Fresnel single-tube compound parabolic collector (CPC) is established. In light of the normal operating conditions during the day, it is found that the direct normal irradiation (DNI) and loop length exert significant effects on the heat collection and thermal loss performance of the linear Fresnel reflector. With the increase of DNI and unit length, the outlet temperature and heat collection capacity of the collector loop increase significantly. Because of the increase of DNI, the increase of collector heat is higher than that of thermal loss. However, the thermal loss per unit length increases correspondingly with the increase in loop length, and the heat collection efficiency decreases. Ambient temperature and wind velocity are not the main factors affecting the heat collection and thermal loss performance of the linear Fresnel reflector under the prerequisite of a good vacuum degree of the collector tube.
Heat Transfer Performance of Water-cooled Heat Sink for I&C System Controller Chip in Nuclear Power Plant
Authors: Fei Guobiao , Xiao Li
Published: September 2023

To improve the heat dissipation reliability of the nuclear power control system chip, the structure of its water-cooled heat sink is compared and analyzed. Three schemes of water-cooled heat sinks are proposed, and CFD analyzes the heat dissipation performance of the heat sink. The simulation data of the heat transfer coefficient, pressure loss, and heat sink comprehensive coefficient are compared. The results show that the average temperature of the bottom surface of the three heat sinks tends to be flat with the flow velocity increase, and the heat dissipation coefficient Nu is also the same. The S-type heat sink has a higher heat transfer coefficient and lower average bottom temperature. The pressure loss of the S-type heat sink is much higher than that of the other two schemes with the increased flow rate, and the system resistance is large. By calculating the comprehensive coefficient of the heat dissipation process of the three heat sinks and considering the heat dissipation capacity and other factors, it is considered that the circular fin heat sink can be the optimal solution.
Middleware Key Technologies Supporting Panoramic Display of Low-voltage Distribution Substation Area Operation
Authors: Shi Zhan , Deng Xiaozhi , Li Xingnan , Yang Zhihua
Published: September 2023

A panoramic display system for low-voltage distribution substation areas is built in this paper to meet the visual monitoring requirements of equipment operation status in low-voltage distribution substation areas. Aiming at the characteristics of complicated data structure, decentralized deployment, and equipment isomerization of power equipment, a middleware for panoramic display system of low-voltage distribution substation area operation is designed. The residual search method realizes the data identification to give a timely warning. Heterogeneous data is clustered by the K-means method. Simulation results verify the better performance of the proposed middleware for low-voltage substation operation.
Design of complex vector regulator for Linear Induction Motor
Authors: Guo Han
Published: September 2023

The edge-end effect in the operation of a Linear Induction Motor (LIM) will lead to great changes in motor parameters, and the d and q axes of LIM have cross-coupling terms. The PI regulator usually used in traditional vector control has a high requirement on the accuracy of parameters, and the PI regulator cannot realize the complete axis decoupling control of d and q, which will lead to the decline of the control accuracy. In this paper, the mathematical model of the LIM considering side effects is adopted, and a complex vector regulator is used to replace the traditional PI regulator, which realizes decoupling control of the d-q axes and eliminates the influence of coupling terms. Finally, this paper is verified on dSPACE semi-physical platform. Results show that the decoupling effect of d-q axes using complex vector regulator is due to the PI regulator.
Site assessment of transformer state based on individual Raman spectrum equipment
Authors: Fang Jian , Lin Xiang , Zhou Fengxiang , Tian Yan , Zhang Min , Li Kairan , Sun Jian
Published: September 2023

The transformer is the pivotal equipment in the power system, and its operating conditions are critical to the entire power grid, so it is important to evaluate its state in a timely manner. A method of site assessment of transformer state by using individual Raman spectrum equipment was presented in this paper. First, transformer oil samples containing different health states were collected by accelerated thermal aging tests and field sampling. The oil samples were then subjected to Raman testing and the Raman spectral features that can reflect the transformer state were extracted based on multidimensional scaling analysis (MDS). The evaluation model of transformer condition based on Raman spectra of insulating oil was constructed by random forest (RF), and the evaluation accuracy was higher than 90% for 20 actual samples. The results of this paper can provide technical support for intelligent operation and maintenance of substations.
The Simulation Analysis and Countermeasures of LCC-HVDC Complementary Resonance
Authors: Su Yinsheng , Liu Zhijiang , Chen Deyang , Xie Huifan , Lin Xuehua , Liu Hongtao
Published: September 2023

With the advancement of HVDC technology, the AC/DC hybrid grid has gradually emerged. The interaction and influence between AC and DC have become increasingly prominent, with the complementary resonance problem between AC and DC emerging as a hot research topic. In this paper, firstly, the phenomenon of LCC-HVDC complementary resonance is analyzed in both time and frequency domains, and a method for setting the saturation curve of the converter transformer in time domain simulation is proposed. Subsequently, targeting the actual LCC-HVDC complementary resonance, a hardware-in-loop simulation platform is constructed based on the actual HVDC control and protection equipment, and the actual field complementary resonance is reproduced. By simulating different operation modes, the operation range with a low risk of complementary resonance is determined. The influencing factors of complementary resonance are discussed and analyzed. Finally, through real-time simulation, the results show that the simulation method proposed in this article for setting the saturation curve of the converter transformer can accurately reflect the complementary resonance phenomenon between AC and DC caused by the saturation of the converter transformer. The countermeasures proposed in this article can effectively remove the complementary resonance between AC and DC and have been applied to the operation and control of actual power grids.
Research on 750kV Reactor Vibration Based on Electromagnetic-mechanical Field Coupling Finite Element Model
Authors: Wu Jianming , Min Yongzhi
Published: September 2023

The vibration signal characteristics of a 750kV shunt reactor with high voltage level and high vibration amplitude is one of the important indexes to evaluate the operating condition of the reactor. Since the high level of safe operation with Ultra-high voltage power equipment, it is challenging to collect long-term and extensive vibration signal data under safe operating conditions. This paper establishes the electromagnetic-mechanical field coupling finite element model (FEM) of a 750kV shunt reactor under a COMSOL open-source simulation environment. The resonance effect of magnetostriction of the iron core and the Maxwell forces between the iron core discs on the reactor structure is analyzed. The vibration distribution and typical frequency characteristics of each part of the 750kV shunt reactor are analyzed to provide a reference for the research of vibration fault diagnosis of Ultra-high shunt reactor.
Wireless Charging Docking Method for Multi-Sensor Integrated Logistics Robot in Substation
Authors: Pan Shuyan , Lu Zijian , Yan Yu , He Yang , Wang LiDe , Yan Kai , Zeng ZhaoQiang , Zhou YunYa
Published: September 2023

To avoid wasting time and manpower during the wireless charging docking process of logistics robots of different sizes and models in substations, which may affect the operational efficiency of the robots, this paper proposes a wireless charging docking method for multi-sensor integrated logistics robots in substations. First, multiple data signals, such as infrared sensors, pressure sensors, and ultrasonic sensors, are fused within the coarse positioning interval to obtain the length and width data of the robot. The robot is then controlled to travel along the X-axis towards the pre-set displacement sensor while maintaining its position relative to the wireless charging transmitter coil. In the fine positioning interval, the distance between the displacement sensor and the wireless charging transmitter coil is fixed. A coarse-precision positioning transformation method is used to decelerate the robot as it travels along the X-axis towards the pre-set displacement sensor, and the robot is parked at the wireless charging transmitter coil. Additionally, two sets of laser sensors are used to compare the lateral distance, which is half the difference between the charging station width and the robot width. This assists the robot in aligning along the Y-axis with the wireless charging transmitter coil and completing the wireless charging docking process. The experimental results show that the wireless charging system has superior docking time and stability compared to traditional docking methods. It is also compatible with multiple logistics robots of different sizes for wireless charging, with a docking error of less than 0.3%. This effectively improves the charging efficiency of robots in substations.
Value Gain-based Power Line Subcarrier Aggregation Method under Colored Noise
Authors: Shi Zhan , Deng Xiaozhi , Li Xingnan , Yang Zhihua , Qian Xin
Published: September 2023

With the large-scale power electronic equipment connected to the distribution network in the form of a new power system, the colored noise generated by power equipment will greatly reduce the efficiency of data transmission. The power line communication subcarrier grouping aggregation method features high transmission efficiency, excellent reliability, and high stability, which can improve the anti-interference and anti-noise performance of power line subcarriers. However, traditional subcarrier packet aggregation methods neglect the network topology changes and node service requirements, resulting in low adaptability of available subcarriers for power electronics scenarios. Therefore, we propose a value gain-based power line subcarrier aggregation method under colored noise. It can achieve adaptive colored noise awareness and dynamically optimize the subcarrier grouping aggregation. Simulation results demonstrate the excellent performance of the proposed algorithm in terms of availability and utilization efficiency.
Research on Voltage Flexibility Analysis and Governance Measures for Distribution Networks with High Proportion
Authors: Qi Xuesong , Wang Yuming , Sun Jia , Guo Tiebin , Li Zhenxin , Guan Xiaozhuo
Published: September 2023

In response to issues such as reduced voltage flexibility caused by the integration of a large number of high-proportion distributed photovoltaic (HPDP) and new energy electric vehicles (NEEV) into the distribution networks, this article proposes a method for evaluating the voltage flexibility (VF) of distributed PV distribution networks with high proportions and corresponding governance measures, which can effectively improve the VF of distribution networks and the absorption rate of photovoltaic (PV) systems. Firstly, we build an integrated system model for PV, electrochemical energy storage (EES), and distributed charging piles (DCP). Then, from a spatial perspective, a VF evaluation method for HPDP distribution networks is proposed. We analyze the impact of HPDP integration on the VF of each node in the distribution network and propose a governance measure that combines EES and DCP to enhance the VF of the distribution network. Finally, we take a typical 10 kV distribution network architecture in Jilin Province as an example for numerical analysis, so the effectiveness of the proposed method is verified.
Voltage Sag Source Location based on the Random Forest
Authors: Li Guoxin , Yu Zhiyuan , Zheng Bowen , Qi Biao , Su Ziqing , Wang Di
Published: September 2023

As one of the most prominent power quality problems in the power system, voltage transients threaten the use of many electrical and electronic devices. The rapid and accurate location of voltage drop sources can better define the responsibility between the power supply and the customer. It can also provide a reliable basis for future grid development planning. In this paper, a random forest model is set up to extract data from several electrical characteristics of voltage transients according to the classical voltage transient location method, which is used as training and test samples to input into the random forest model to achieve the upstream and downstream location of voltage transient sources. The random forest model is more accurate than the single decision tree model and the traditional upstream and downstream voltage drop location method. It is possible to determine which of the traditional judgments is more important under this model.
Active Disturbance rejection Hopf bifurcation suppression strategy based on DC microgrid DC-DC converter
Authors: Zhang Jiangong , Zhou Xuesong , Ma Youjie , Yuan Yecang , Duan Jianxiong , Wang Bo
Published: September 2023

To solve the problem that the output voltage of the Buck converter is easily affected by the change of system parameters, which reduces the energy transmission quality, a linear active disturbance rejection control strategy is proposed in this paper. Firstly, a discrete mathematical model is established to analyze that Hopf bifurcation disturbance is the cause of low-frequency oscillation of output voltage, and the existence of Hopf bifurcation disturbance is verified by simulation. Secondly, based on the theoretical analysis, the suppression effect of improving the error feedback control rate on Hopf bifurcation disturbance is designed. Moreover, the stability of the control strategy under Hopf bifurcation disturbance is analyzed by using frequency-domain theory. Finally, the suppression of Hopf bifurcation disturbance by the proposed control strategy and the traditional PI control strategy under different working conditions is compared by simulation analysis. The results show that the proposed linear active disturbance rejection control strategy can effectively suppress Hopf bifurcation disturbance and guarantee the performance of the Buck converter.
Comprehensive Condition-Information-Based Risk Assessment Method for Power Transmission Line
Authors: Wang Xiulong , Han Jingshan , Fan Wenqi , Jiang Hong , Guo Yifan , Peng Jiang , Ge Huangxu , Zhao Mengshi
Published: September 2023

The traditional risk assessment methods do not adequately consider the specific operating environment and characteristics of a power transmission line. Therefore, a new risk assessment method considering the information of comprehensive conditions is proposed in this paper. First, a risk assessment model is designed via statistical methods based on the information on preceding failures and defects of a power transmission line. Then, the quantization processes of the state parameters of components in the transmission line are formed to get the risk assessment results considering historical failure information. These results are of failure probability meaning. Finally, the influences of the operating age of equipment in the transmission line, the position of the transmission line, the service time, and the working condition of the grid on the risk value of the transmission line are analyzed. An empirical example shows that the suggested method can predict the risks of transmission lines and offers a way for maintenance scheduling and equipment replacement.
PIV wake survey of a drone propeller for amphibious applications
Authors: Grizzi Silvano , Falchi Massimo , Martellini Edoardo , Aloisio Giovanni , Pagliaroli Tiziano
Published: September 2023

Aerial and underwater drones are one of the most attractive technologies to a large number of applications, extending from surveillance of natural reserves to the monitoring of structures. For these reasons, innovative and uncommon applications are constantly appearing. Within this context, drones capable to operate continuously and efficiently in air and water can extend the standard aerial capabilities allowing underwater inspections of harbour structures, pipelines or marine reserves. For this reason, an attractive characteristic for drones is the capability to manoeuvre in different fluids as air and water. This article presents an experimental campaign, carried out both in a towing tank and in a cavitation tunnel, aimed at study the fluid-dynamics of an aeronautic drone-propeller in off-design conditions. Dynamometric, PIV and Stereo-PIV tests are carried out to evaluate the aeronautic propeller functioning in water and optimize it for amphibious missions. In particular, the forces are measured for different advance ratios J provided by varying both rotational regime and free stream velocity, in open water conditions (Towing tank tests) and in confined water (Cavitation tunnel tests). PIV and Stereo-PIV fields, acquired in the Cavitation tunnel, allow us to investigate the behaviour of the propeller in the water in a number of selected, operative conditions.
Diversity and potential role of mammals in oil palm agroecosystem (case study in PT Permata Sawit Mandiri, West Kalimantan)
Authors: Laksmitha N
Published: September 2023

The palm oil industry as the mainstay sector is still accused of being unsustainable due to the high use of chemicals as fertilizer and pest control. These inefficiencies can cause environmental damage and increase production costs. Based on these problems, it is necessary to optimize the role of biodiversity to increase oil palm productivity. This study aims to identify the diversity of mammals in several types of land cover and to analyze the role of mammals in the oil palm agroecosystem. This research was carried out on 6 types of land cover at PT Permata Sawit Mandiri, West Kalimantan in January–April 2020. Diversity data was obtained using a combination of line transects and observation points, while role data was obtained through literature study. The transect method used measuring 100 × 1000 meters is one for each type of land cover. The observations were made in the morning (06.00-08.00) and afternoon (15.30-17.30) for three repetitions each time. The results showed that there were 60 individuals from 11 species belonging to 6 families. The highest number of encounters and species variation was found in HG land cover. Mammals are one of the taxa that play an important role in maintaining ecological processes. Based on the list of mammal species in the study area, five of these species have potential roles for the oil palm agorecosystem. These roles as seed dispersers include Callosciurus notatus; Callosciurus prevostii; and Macaca fascicularis, as well as pest controllers Prionailurus bengalensis and Helarctos malayanus. The HG land cover type has a complete composisition of the roles of mammals, while in the SS land cover, no mammal species play a role in the oil palm agroecosystem.
Comparison of MSD analysis from single particle tracking with MSD from images. Getting the best of both worlds
Authors: Kettmayer Constanza , Gratton Enrico , Estrada Laura C
Published: September 2023

Fluorescence microscopy can provide valuable information about cell interior dynamics. Particularly, mean squared displacement (MSD) analysis is widely used to characterize proteins and sub-cellular structures’ mobility providing the laws of molecular diffusion. The MSD curve is traditionally extracted from individual trajectories recorded by single-particle tracking-based techniques. More recently, image correlation methods like iMSD have been shown capable of providing averaged dynamic information directly from images, without the need for isolation and localization of individual particles. iMSD is a powerful technique that has been successfully applied to many different biological problems, over a wide spatial and temporal scales. The aim of this work is to review and compare these two well-established methodologies and their performance in different situations, to give an insight on how to make the most out of their unique characteristics. We show the analysis of the same datasets by the two methods. Regardless of the experimental differences in the input data for MSD or iMSD analysis, our results show that the two approaches can address equivalent questions for free diffusing systems. We focused on studying a range of diffusion coefficients between D = 0.001 μm2 s−1 and D = 0.1 μm2 s−1, where we verified that the equivalence is maintained even for the case of isolated particles. This opens new opportunities for studying intracellular dynamics using equipment commonly available in any biophysical laboratory.
Analysis of misalignment characteristics for textured foil journal bearing based on multigrid method
Authors: Xu Kefan , Zhang Guanghui , Han Jiazhen , Wang Qiang , Huang Yanzhong , Gong Wenjie , Guo Yang , Liu Zhe , Sun Wenlong
Published: September 2023

Surface texturing is an excellent solution to the load capacity deficiency of foil journal bearings. However, it will also introduce significant discretization efforts. This paper explored the possibility of searching the static balance locus of textured foil journal bearing using the multigrid method to ensure design efficiency. The modified Reynolds equation characterized the ultra-thin gas film behavior inside bump-type foil bearing, and two foil models were adopted simultaneously to obtain the foil’s structural deflection. The predicted load capacity agreed well with the experimental data. The results indicate that multigrid can accelerate the solution process of the compressible pressure governing equation, and the speed can be increased up to 70% when the nonlinear discretization scheme is adopted. It is recommended that textures are located in the pressure-rising region along the shaft’s rotating direction and that the axial direction is fully textured to improve load capacity. Moreover, the above texture distribution scheme can increase the tolerable maximum misalignment angle by 11.8% and enhance the stability of rotors operated in light-load and high-speed cases.
Xiuyan jade waste as antibacterial additives for functional coatings
Authors: Wang Jimei , Wang Xiaoyan , Yang Yang
Published: September 2023

Jade waste is a normal byproduct that makes up much more than the amount of jade extracted. Therefore, recycling jade waste is worth investigating from the point of view of energy conservation. Moreover, it is an environment-friendly material, which is desirable for use in building materials. In this study, Xiuyan jade waste was repurposed as antibacterial additives for building coatings. The powder waste was activated by milling and subsequent annealing. The antibacterial properties of the treated waste were mostly related to the annealing temperatures. Based on the investigations of the phase change and the release of metal ions of a series of samples and their antibacterial activities, the antibacterial mechanism of the treated samples was explored experimentally. The most applicable sample for coatings was finally chosen by considering its pH values and its antibacterial abilities. Antibacterial testing showed that the addition of treated jade waste could enhance the bacterial inhibition rate of building coatings from 60% to 99.9%.
Pancake-like antiphase domains in perfect nitrogen-expanded austenite by TEM characterization
Authors: Che H L , Yang X , Lei M K
Published: September 2023

Elongated superstructure diffraction spots were observed in perfect nitrogen-expanded austenite without stress or plastic strain, which was prepared by plasma-based low-energy nitrogen-ion implanting Fe-Cr-Ni austenitic alloy foils at low temperature of 380 °C. The Fe4N-like ordered nitrogen-expanded austenite (γ′N) antiphase domains formed in the disordered nitrogen-expanded austenite (γ
N) matrix. Only the high Cr-content alloys presented elongated diffraction spots. The reconstruction of the diffraction spots strength distribution shows an elongated egg-shape in reciprocal space. This elongation corresponded to a pancake-like antiphase domains distribution in matrix, which was confirmed in dark field images as a lamellar structural feature. The Cr-N short-range ordering (SRO) and anisotropic elastic module rather than the constrained strain in the γ
N phase layer determine the formation of γ′N antiphase domains.
Microstructure evolution and strengthening mechanism of air-hardening steel subjected to the austenitizing annealing treatment
Authors: Yang Yonggang , Luo Xiang , Lei Minggang , Fang Xing , Li Shouhua , Wu Yanxin , Mi Zhenli
Published: September 2023

The microstructure evolution and mechanical properties of air-hardening steel subjected to different austenitizing annealing treatments were investigated in this study and, especially, the precipitation behavior of the steel was analyzed, as well as the strengthening mechanism of the steel was elucidated on the basis of systematic microstructural characterization. Results reveal that a ferrite + martensite dual-phase structure with about 700 MPa tensile strength and 20% elongation can be obtained by austenitizing the experimental steel in the range of 750∼800 °C; while austenitizing between 850 °C and 950 °C results in granular bainite + lath bainite with about 950 MPa tensile strength and 12% elongation. The experimental steel has the highest strength after austenitizing at 900 °C with lots of nano-scale (Ti, Mo, V)C particles distributed in its matrix. Quantitative calculation results illustrate that the main strengthening factors are grain refinement strengthening, dislocation strengthening and precipitation strengthening. In addition, due to the potential interaction effect between different strengthening factors, a modified strengthening model is proposed to describe the strengthening behavior of the air-hardening steel when it is heat-treated in the two-phase region.
Low-temperature electrolytes for electrochemical energy storage devices: bulk and interfacial properties
Authors: Yang Long , Chen Ming , Wu Taizheng , Niu Liang , Zeng Liang , Feng Guang
Published: September 2023

The optimization of electrochemical energy storage devices (EES) for low-temperature conditions is crucial in light of the growing demand for convenient living in such environments. Sluggish ion transport or the freezing of electrolytes at the electrode-electrolyte interface are the primary factors that limit the performance of EES under low temperatures, leading to fading of capacity and instability in device performance. This review provides a comprehensive overview of antifreeze strategies for various electrolytes (including aqueous electrolytes, organic electrolytes, and ionic liquids), and optimization methods for ion transport at the electrolyte-electrode. Additionally, the main challenges and forward-looking views are highlighted on the design and development of low-temperature electrolytes and EES devices.
Evolution characteristics of rural carbon emissions in Northwest China from 2006 to 2019
Authors: Wang Yan , Zhang Liyuan , Zhang Yue , Zhong Wei , Pei Kunru , Qiao Wei , Jiao Qian , Cao Wei
Published: September 2023

China is faced with significant challenges in simultaneously promoting rural development and reducing carbon emissions. However, the issue of quantifying and addressing carbon emissions in rural areas has not been adequately addressed. Accurately quantifying these emissions is crucial for developing effective strategies to reduce carbon output. In this study, the historical evolution and spatial distribution of rural carbon emissions in northwestern China from 2006 to 2019 were evaluated across five key sectors: residential energy consumption, agricultural machinery, solid waste management, planting practices, and breeding industry activities. During this period, total carbon emissions in rural areas of northwest China steadily increased from 60.15Mt to 83.49Mt at an annual growth rate of 2.55%. Given the complex interplay between economic and social factors driving these changes, the future trajectory of rural carbon emissions remains uncertain. To analyze the underlying drivers behind regional variations in carbon emissions over time, we constructed an LMDI model which revealed that economic growth primarily contributed to regional increases in carbon output. Furthermore, due to a remarkable annual growth rate of 35.17% in renewable energy generation (such as photovoltaic and wind power), it can be inferred that if renewable electricity were included within our calculations for carbon emission statistics, northwest China’s rural areas achieved a state of being effectively ‘carbon-neutral’ by 2019 solely from a production-based perspective.
Impact of electronic correlations on high-pressure iron: insights from time-dependent density functional theory
Authors: Ramakrishna K , Lokamani M , Baczewski A , Vorberger J , Cangi A
Published: September 2023

We present a comprehensive investigation of the electrical and thermal conductivity of iron under high pressures at ambient temperature, employing the real-time formulation of time-dependent density functional theory (RT-TDDFT). Specifically, we examine the influence of a Hubbard correction (+U) to account for strong electron correlations. Our calculations based on RT-TDDFT demonstrate that the evaluated electrical conductivity for both high-pressure body-centered cubic (BCC) and hexagonal close-packed (HCP) iron phases agrees well with experimental data. Furthermore, we explore the anisotropy in the thermal conductivity of HCP iron under high pressure, and our findings are consistent with experimental observations. Interestingly, we find that the incorporation of the +U correction significantly impacts the ground state and linear response properties of iron at pressures below 50 GPa, with its influence diminishing as pressure increases. This study offers valuable insights into the influence of electronic correlations on the electronic transport properties of iron under extreme conditions.
Energy beam-based direct and assisted polishing techniques for diamond: A review
Authors: Li Zhuo , Jiang Feng , Jiang Zhengyi , Tian Zige , Qiu Tian , Zhang Tao , Wen Qiuling , Lu Xizhao , Lu Jing , Huang Hui
Published: September 2023

Diamond is a highly valuable material with diverse industrial applications, particularly in the fields of semiconductor, optics, and high-power electronics. However, its high hardness and chemical stability make it difficult to realize high-efficiency and ultra-low damage machining of diamond. To address these challenges, several polishing methods have been developed for both single crystal diamond (SCD) and polycrystalline diamond (PCD), including mechanical, chemical, laser, and ion beam processing methods. In this review, the characteristics and application scope of various polishing technologies for SCD and PCD are highlighted. Specifically, various energy beam-based direct and assisted polishing technologies, such as laser polishing, ion beam polishing, plasma-assisted polishing, and laser-assisted polishing, are summarized. The current research progress, material removal mechanism, and influencing factors of each polishing technology are analyzed. Although some of these methods can achieve high material removal rates or reduce surface roughness, no single method can meet all the requirements. Finally, the future development prospects and application directions of different polishing technologies are presented.
Deep neural network based downlink power domain multi-user NOMA-OFDM signal detection
Authors: Singh Abhiranjan , Saha Seemanti
Published: September 2023

Non-orthogonal multiple access-based orthogonal frequency division multiplexing (NOMA-OFDM) is a promising waveform-based multiple access technology for future wireless networks for multiple-user symbol transmission (MUST) in the same time-frequency resource block. However, it differs in the power domain, enhancing its spectrum efficiency. This is essential to meet the high data rate required for ever-increasing connected devices and the Internet of Things (IoT). However, NOMA-OFDM systems suffer from impairments such as imperfect successive interference cancellation (SIC) caused by channel impairments like channel fading, carrier frequency offset, and non-linearity caused by non-linear power amplifiers. This paper identifies and addresses the key impairments mentioned in the NOMA-OFDM system and proposes DNN-based estimation in offline training and detection in online testing for downlink power domain multi-user NOMA-OFDM symbols. The reported 2 dB SNR gain compared to least square-SIC/minimum mean square error SIC-based methods is a significant finding and demonstrates the robustness of the proposed DNN-aided approach against various channel impairments.
Efficacy of indocyanine green fluorescence for the identification of non-palpable breast tumours: systematic review
Authors: Jansen Britt A M , Bargon Claudia A , Huibers Anne E , Postma Emily L , Young-Afat Danny A , Verkooijen Helena M , Doeksen Annemiek
Published: September 2023

Background

Accurate tumour localization is crucial for precise surgical targeting and complete tumour removal. Indocyanine green fluorescence, an increasingly used technique in oncological surgery, has shown promise in localizing non-palpable breast tumours. The aim of this systematic review was to describe the efficacy of indocyanine green fluorescence for the identification of non-palpable breast tumours.

Methods

A systematic literature search was performed in PubMed, Embase, and the Cochrane Library, including studies from 2012 to 2023. Studies reporting the proportion of breast tumours identified using indocyanine green fluorescence were included. The quality of the studies and their risk of bias were appraised using the Methodological Index for Non-Randomized Studies (‘MINORS’) tool. The following outcomes were collected: identification rate, clear resection margins, specimen volume, operative time, re-operation rate, adverse events, and complications.

Results

In total, 2061 articles were screened for eligibility, resulting in 11 studies, with 366 patients included: two RCTs, three non-randomized comparative studies, four single-arm studies, and two case reports. All studies achieved a 100 per cent tumour identification rate with indocyanine green fluorescence, except for one study, with an identification rate of 87 per cent (13/15). Clear resection margins were found in 88–100 per cent of all patients. Reoperation rates ranged from 0.0 to 5.4 per cent and no complications or adverse events related to indocyanine green occurred.

Conclusion

Indocyanine green fluorescence has substantial theoretical advantages compared with current routine localization methods. Although a limited number of studies were available, the current literature suggests that indocyanine green fluorescence is a useful, accurate, and safe technique for the intraoperative localization of non-palpable breast tumours, with equivalent efficacy compared with other localization techniques, potentially reducing tumour-positive margins.
Systematic review on groove pancreatitis: management of a rare disease
Authors: Ukegjini Kristjan , Steffen Thomas , Tarantino Ignazio , Jonas Jan P , Rössler Fabian , Petrowsky Henrik , Gubler Christoph , Müller Philip C , Oberkofler Christian E
Published: September 2023

Background

Groove pancreatitis is a focal form of chronic pancreatitis affecting the area of the paraduodenal groove. The aim of this systematic review was to assess the clinical presentation, diagnosis and treatment of patients with groove pancreatitis.

Methods

Medical literature databases (Embase, Medline via PubMed and Cochrane Central Register of Controlled Trials) were systematically searched for data recorded between 1 January 1990 and 31 August 2022 regarding patient characteristics, diagnosis, surgical treatment and outcomes. The following inclusion criteria were applied: RCTs, observational studies (cohort and case–control studies) and case studies with >3 cases including patients with groove pancreatitis undergoing medical, endoscopic or surgical treatment with available clinical and diagnostic data. Fisher’s exact test for binary data and Mann–Whitney U test or Student t-test for continuous data were adopted for statistical analysis.

Results

Of 649 studies, 44 were included, involving reports on 1404 patients with a mean age of 49 years. In 41 of the 44 studies in which patient gender was described, 86 per cent (N = 1023) of patients were male. Information on the risk factors of alcohol and nicotine was available in 37 and 23 studies, respectively. Seventy-nine per cent (N = 886) of patients had a history of excessive alcohol consumption and 83 per cent (N = 595) were smokers. Information on clinical symptoms was available in 37 of the 44 included studies and 78.5 per cent (N = 870) presented with abdominal pain. Some 27 studies comprising 920 groove pancreatitis patients were treatment oriented. Seventy-four per cent (N = 682) of patients were treated conservatively, 26.4 per cent (N = 134) underwent endoscopic treatment and 54.7 per cent (N = 503) required surgery. There was complete relief of symptoms in 35.6 per cent (N = 243) after conservative treatment, 55.2 per cent (N = 74) after endoscopic treatment and 69.6 per cent (N = 350) after surgical treatment. The median follow-up time was 42 months (range, 1–161 months).

Conclusion

Groove pancreatitis shows on imaging a typical triad: cystic lesions in the pancreatic duct or duodenal wall, calcifications, and thickenings of the duodenal wall. Surgery appears to be the most effective treatment modality.
Cut homeodomain transcription factor is a novel regulator of growth and morphogenesis of cortex glia niche around neural cells
Authors: Yadav Vaishali , Mishra Ramkrishna , Das Papri , Arya Richa
Published: September 2023

Cortex glia in Drosophila central nervous system form a niche around neural cells for necessary signals to establish cross talk with their surroundings. These cells grow and expand their thin processes around neural cell bodies. Although essential for the development and function of the nervous system, how these cells make extensive and intricate connected networks remains largely unknown. In this study, we show that Cut, a homeodomain transcription factor, directly regulates the fate of the cortex glia, impacting neural stem cell (NSC) homeostasis. Focusing on the thoracic ventral nerve cord, we found that Cut is required for the normal growth and development of cortex glia and timely increase in DNA content through endocycle to later divide via acytokinetic mitosis. Knockdown of Cut in cortex glia significantly reduces the growth of cellular processes, the network around NSCs, and their progeny's cell bodies. Conversely, overexpression of Cut induces overall growth of the main processes at the expense of side ones. Whereas the Cut knockdown slows down the timely increase of DNA, the Cut overexpression results in a significant increase in nuclear size and volume and a 3-fold increase in DNA content of cortex glia. Further, we note that constitutively high Cut also interfered with nuclei separation during acytokinetic mitosis. Since the cortex glia form syncytial networks around neural cells, the finding identifies Cut as a novel regulator of glial growth and variant cell cycles to support a functional nervous system.
4. The changing role of data in crime, criminal justice, and criminology
Authors: Matthews Ben , McVie Susan
Published: September 2023

Data has always been at the heart of criminological endeavours and underpins some of its most important theoretical and conceptual developments. Recent advances in technology, computer science, and data expansion have fundamentally re-shaped society and impacted significantly on various aspects of crime and justice. Such developments have posed challenges for traditional methods of defining and measuring crime, but also opened up novel sources of information such as citizen generated ‘counterdata’. The increasing availability of data has shaped the working practices and policies of criminal justice organizations, which use increasingly sophisticated approaches towards prevention and prediction on the one hand, and surveillance and social control on the other. And while new opportunities for criminology have increased in terms of methodological expansion and theoretical development, potential risks have emerged in terms of replicability, reputation and disciplinary integrity. In this chapter, we take a critical approach to examining the contemporary role of data in shaping crime, criminal justice and criminology, with specific reference to methodological innovations, conceptual debates, ethical controversies, and disciplinary dilemmas.
8. Drug use, drug problems, drug control: A political economy perspective
Authors: Seddon Toby , Stevens Alex
Published: September 2023

This chapter presents an overview of the phenomenon of illicit drugs and their control. We show that drugs are not just a matter of crime, morality, or health but rather are also a global commodity the use and control of which continue to run along lines shaped by inequalities of geography, wealth and power. Viewing the drug problem through the lens of political economy, and in global and historical perspective, provides a clearer view of the issue. It allows us to see how some facets of the problem are exaggerated (e.g. crime and health harms) whilst others are under-stated (e.g. pleasure, harms to producer countries in the Global South). It also sheds new light on why some policy approaches and interventions continue to fail and why others may be more promising. Lastly, the prospects for radical alternatives to prohibition through drug law reform are considered.
10. Public opinion, crime, and criminal justice
Authors: Hough Mike , Roberts Julian V.
Published: September 2023

This chapter summarizes research on public opinion about crime and criminal justice in developed industrialized societies. It starts with an assessment of what can be said about public knowledge about crime, documenting widespread misperceptions about the nature of crime, about crime trends, and about the criminal justice response to crime. It then considers public attitudes towards crime and justice, which tend to be largely negative. The chapter presents evidence of the links between levels of knowledge and attitudes to justice, suggesting that misinformation about crime and justice is the likely source of negative public ratings of the justice system. Penal populism and populist punitiveness are considered. The chapter ends by exploring issues of public trust in justice, confidence, and legitimacy.
11. Crime news, trial by media, and scandal hunting
Authors: Greer Chris , McLaughlin Eugene
Published: September 2023

A rapidly evolving digital media landscape, inhabited by a network of outlets, is amplifying crime consciousness, exploiting crime’s infotainment potential, and reshaping public attitudes towards crime and criminal justice. At the same time, in depth analysis of crime news has dropped off the criminological radar. In this chapter, we argue that because criminologists have not kept pace with transforming news media and markets, crime news remains under-researched and under-conceptualized. We begin by revisiting three classic concepts that continue to dominate crime news research: newsworthiness, moral panic, and penal populism. Though these concepts are still important for understanding crime news, their institutionalization and taxonomical application within criminology has marginalized analysis of dramatic shifts in the production and nature of crime news, the markets in which it circulates, and its power to shape crime consciousness and criminal justice rhetoric and practice. We then explore how ‘trial by media’ and ‘scandal hunting’ are not only redefining crime news, but also exposing institutional failures in public protection and challenging both the efficacy and the legitimacy of the criminal justice system. It is in this context of an unruly networked digital environment that we situate the disruptive challenge posed to criminal justice by the rise of what we define as media justice.
14. Demystifying hate crime in an age of crises
Authors: Chakraborti Neil , Clarke Amy
Published: September 2023

This chapter examines the extent of hate crimes in the age of crises. It acknowledges how the concept of hate crime is notoriously complex and contested. The continued rise of hate incidents paints a worrying picture of seemingly legitimized hostile and prejudiced attitudes rooted within wider structural inequalities. Even though ne and physical hostility is normalized, legitimized, and politically weaponized, there is a deafening silence from national governments when it comes to addressing the underlying causes of hate crime. The chapter considers the complex realities of perpetration and victimization in an effort to improve responses to hate crime in times of increasing fragility and uncertainty.
22. White-collar and corporate crime
Authors: Levi Michael , Lord Nicholas
Published: September 2023

This chapter covers the changing conceptions of crime and social order in correlation with the character and quality of everyday life in contemporary Britain. It presents elements of change that involve notions of durability and persistence. The contemporary landscapes of sources of harm, uncertainty, or tribulation that attend people’s everyday lives are diverse and bear upon different lives and different habitats in very distinct and unequal ways. As measured by victimization surveys and other means, fear of crime always had as its primary object threats to personal safety in public space. The chapter also considers the contentions surrounding the notion of security and public safety.